WO2018020967A1 - Novolac-type cocondensation product to be compounded into rubber, and method for producing said cocondensation product - Google Patents

Abstract

Provided is a method for producing a novolac-type cocondensation product, wherein the novolac-type cocondensation product contains a structural unit derived from at least one phenol compound represented by general formula (i), a structural unit derived from formaldehyde and a structural unit derived from resorcin, and a structural unit derived from p-tert-butylphenol makes up 65 mol% or more of the structural unit derived from the phenol compound. The production method involves, in this order, the steps of (1) reacting the phenol compound with formaldehyde at 75ºC or higher in the presence of a base in an amount of 0.05 mole or more relative to 1 mole of the phenol compound to produce a resol-type condensation product having a number average molecular weight of 600 or more as measured by a GPC method, (2) mixing a reaction solution containing the resol-type condensation product produced in step (1) with an acid in an equivalent amount to the amount of the base used in step (1) or more, and (3) reacting the resol-type condensation product with resorcin in an amount of 0.5 to 1.2 moles relative to 1 mole of the phenol compound.

Description

NOVOLAC TYPE COCONDENSATE FOR RUBBER COMPOSITION AND METHOD FOR PRODUCING THE COCONDENSATE

The present invention provides an improved process for producing a novolac-type cocondensate obtained from alkylphenol or phenylphenol (hereinafter sometimes referred to as phenols) used as an adhesive used in rubber processing, The present invention relates to a novolak-type cocondensate obtained, a resin composition containing the novolak-type cocondensate, and a rubber composition containing the novolak-type cocondensate or the resin composition.

In rubber products that need to be reinforced with reinforcing materials such as steel cords and organic fibers, such as tires, belts, hoses, etc., strong adhesion between the rubber and the reinforcing material is required. In order to bond with rubber, a method of treating a reinforcing material with various adhesives and a method of blending an adhesive together with other various compounding agents in a rubber processing step are known. Among these methods, a method of blending an adhesive in the rubber processing step is widely adopted because it can be firmly vulcanized and bonded regardless of whether or not the reinforcing material is treated with an adhesive.

On the other hand, the adhesive used in the rubber processing step needs to be softened in the rubber processing step. For example, in the tire rubber field where the adhesive is suitably used, it is generally known that the temperature of the rubber processing step is about 170 ° C. [For example, Journal of Japan Rubber Association Vol. 73 (2000), no. 9, p 488-493 (Non-Patent Document 1)]. Therefore, the adhesive used in the rubber processing step is required to have a softening point sufficiently lower than the maximum temperature during rubber processing and 150 ° C. or less. Further, from the viewpoint of improving dispersibility during use of the adhesive, it is preferable that the softening point of the adhesive is as low as possible so that the adhesive does not block during storage. As an adhesive used in such a rubber processing step, a condensate is obtained by reacting phenols such as p-tert-octylphenol or p-nonylphenol with formalins, and resorcin is reacted with the condensate. Cocondensates are widely used [for example, Japanese Patent Application Laid-Open No. 06-234824 (Patent Document 1)].

However, p-tert-octylphenol and p-nonylphenol are now candidates for SVHC (substances of very high concern) as stipulated in the REACH regulations, which are regulations in the EU, and their use may be restricted in the EU in the future. It is high.

Therefore, the development of co-condensates containing structural units derived from phenol and resorcin using phenols other than p-tert-octylphenol and p-nonylphenol, which are adhesives used in rubber processing processes, has been promoted. ing. For example, Japanese Patent Application Laid-Open No. 2014-152220 (Patent Document 2) discloses a cocondensate using only p-tert-butylphenol as a phenol and having a softening point of 80 ° C. or higher and 190 ° C. or lower; The manufacturing method is described. Then, when the present inventors reexamined the method described in the document, it was found that the obtained cocondensate has high hygroscopicity and easily blocks. Furthermore, when the obtained cocondensate was used as an adhesive used in a rubber processing step, problems such as foaming of the rubber occurred, and it was found that it was inappropriate as the adhesive.

JP-A-2015-052097 (Patent Document 3) describes a co-condensate using p-tert-butylphenol and o-phenylphenol as phenols.

Japanese Patent Application Laid-Open No. 06-234824 JP 2014-152220 A Japanese Patent Laid-Open No. 2015-052097

Journal of Japan Rubber Association Vol. 73 (2000), no. 9, p488-493

Patent Document 3 shows that when only p-tert-butylphenol is used as the phenol, its softening point is very high (200 ° C. or higher) and it is not suitable as an adhesive used in rubber processing. Therefore, it is described that the combined use of o-phenylphenol significantly reduces the softening point of the cocondensate and can be suitably used as an adhesive used in the rubber processing step. However, o-phenylphenol is expensive. If possible, it is desirable not to use o-phenylphenol together or to reduce the amount of use as much as possible.

Therefore, the inventors of the present application examined whether or not the amount of o-phenylphenol used can be reduced based on the method described in Patent Document 3. As a result, the usage ratio of p-tert-butylphenol was determined to be between o-phenylphenol and p-phenylphenol. When the total amount of tert-butylphenol exceeds 65 mol%, when resorcin is reacted with a resole-type condensate obtained by reacting phenols with formalin, fluidity is reduced due to swelling or foaming of the reaction solution, reaction Since liquid non-uniformity occurs and handling property is remarkably deteriorated, industrial production may be difficult, and the softening point of the resulting cocondensate may exceed 150 ° C.

An object of the present invention is a novolak-type cocondensate containing p-tert-butylphenol as a main component, having a softening point similar to that of a conventionally known novolak-type cocondensate, and does not block during storage, and is a rubber Another object of the present invention is to provide a cocondensate having sufficient performance as an adhesive used in the processing step and a method for producing the same.

As a result of intensive studies aimed at solving the problems by the present inventors, a novolak-type cocondensate containing structural units derived from phenols, formaldehyde and resorcin containing p-tert-butylphenol as a main component under the following specific conditions It has been found that the above problem can be solved by producing Specifically, the following invention is included.

[1]
A method for producing a novolac-type cocondensate,
The novolac-type cocondensate has the following general formula (i):

(R represents an optionally substituted alkyl group having 1 to 12 carbon atoms or a phenyl group.)
Including one or more phenols represented by the formula, formaldehyde and resorcin-derived structural units,
The structural unit derived from phenols contains 65 mol% or more of a structural unit derived from p-tert-butylphenol,
The manufacturing method includes the following steps (1), (2) and (3) in this order.
(1) The number average molecular weight (Mn) in the gel permeation chromatography (GPC) method by reacting the phenols with formaldehyde at 75 ° C. or higher in the presence of 0.05 mol or more of base with respect to 1 mol of the phenols. Is a step of obtaining a resol-type condensate having 600 or more
(2) A step of mixing the reaction liquid containing the resol-type condensate obtained in the step (1) with an acid of an equivalent amount or more with respect to the base used in the step (1).
(3) A step of reacting the resole type condensate with 0.5 to 1.2 moles of resorcin to 1 mole of the phenols.

[2]
The method for producing a novolac type cocondensate according to [1], wherein the amount of resorcin used is 0.5 to 0.8 mol per mol of the phenols.

[3]
The production of the novolak-type cocondensate according to [1] or [2], wherein the amount of the base used in the step (1) is 0.05 to 0.25 mol with respect to 1 mol of the phenol. Method.

[4]
A novolak type cocondensate satisfying all of the following (a) to (e).
(A) The following general formula (i):

(R represents an optionally substituted alkyl group having 1 to 12 carbon atoms or a phenyl group.)
The structural unit derived from 1 type, or 2 or more types of phenols represented by these, formaldehyde, and resorcinol is included.
(B) The phenol-derived structural unit contains 65 mol% or more of a structural unit derived from p-tert-butylphenol.
(C) The number average molecular weight (Mn) in the gel permeation chromatograph (GPC) method is 750 or more.
(D) Softening point is 80 to 150 ° C.
(E) The structural unit derived from resorcin is 0.80 mol or less with respect to 1 mol of the structural unit derived from the phenols.

[5]
The novolak-type cocondensate according to [4], further satisfying the following (f).
(F) A component (oligomer 2) having a peak top molecular weight of 700 to 520 in an area percentage of 1 to 10% and a peak top molecular weight of 430 to 320 (oligomer 2) in a gel permeation chromatograph (GPC) method. The area percentage is 0.01 to 2%.

[6]
The novolak-type cocondensate according to [4] or [5], wherein the spectral transmittance at a wavelength of 610 nm of a solution prepared by dissolving 2.0 g of the novolak-type cocondensate in 20 mL of tetrahydrofuran is 80% or more.

[7]
[4] A resin composition comprising the novolak cocondensate according to any one of [6] and a softening agent.

[8]
[7] The resin composition according to [7], wherein the softening agent is a fatty acid having 8 to 32 carbon atoms.

[9]
[7] The resin composition according to [7], wherein the softening agent is cashew nut shell liquid (CNSL).

[10]
The resin composition according to any one of [7] to [9], wherein the content of the softening agent in the resin composition is 5 to 40% by weight.

[11]
The resin composition according to any one of [7] to [10], wherein a spectral transmittance at a wavelength of 610 nm of a solution obtained by dissolving 2.0 g of the resin composition in 20 mL of tetrahydrofuran is 80% or more.

[12]
A rubber composition comprising the novolak-type cocondensate according to any of [4] to [6] or the resin composition according to any of [7] to [11] and a rubber component.

According to the present invention, it is a novolak type cocondensation containing p-tert-butylphenol as a main component and has a softening point comparable to that of a conventionally known novolak type cocondensate, and does not block during storage, Obstacles to industrial implementation, such as reducing the fluidity due to swelling or foaming of the reaction liquid, non-uniformity of the reaction liquid, etc. during the production of co-condensates with sufficient performance as adhesives used in the processing process It becomes possible to manufacture without causing the problem.

Furthermore, according to the production method of the present invention, a novolak using only p-tert-butylphenol as a phenol, which has been unsuitable as an adhesive used in a rubber processing step because of a high softening point in a conventionally known method. Even if it is a type | mold cocondensate, the softening point of this cocondensate can be reduced to such an extent that it can be used as an adhesive used in a rubber processing step without reducing the performance as an adhesive. . Moreover, according to one embodiment of the production method of the present invention, it is also possible to provide a cocondensate having an improved odor if necessary while maintaining the performance as an adhesive.

In addition, the novolak cocondensate obtained by the production method of the present invention was found to be compatible with cashew nut shell liquid (CNSL) and fatty acids having 8 to 32 carbon atoms such as stearic acid. . Since the fatty acids are widely used as vulcanization aids in the rubber processing step, when it is desired to further reduce the softening point of the co-condensate of the present invention, a substance not normally used in the rubber processing step is used as a softening agent. There is no need to use it, and it can also be suitably used in applications where a substance added separately as a softening agent is problematic (for example, rubber in which the softening agent reacts with other components contained in the rubber).

<Method for producing novolak-type cocondensate>
The production method of the novolak type cocondensate of the present invention will be described in detail. The method for producing a novolak type cocondensate according to the present invention includes the following steps (1), (2) and (3) in this order.
(1) One or more types represented by the above general formula (i) in the presence of 0.05 mol or more of base with respect to 1 mol of one or more phenols represented by the above general formula (i) or A step of reacting two or more kinds of phenols with formaldehyde at 75 ° C. or higher to obtain a resol-type condensate having a number average molecular weight (Mn) of 600 or more in a gel permeation chromatograph (GPC) method.
(2) A step of mixing the reaction solution containing the resol-type condensate obtained in step (1) with an acid equivalent to or more than the base used in step (1).
(3) A step of reacting resole-type condensate with 0.5 to 1.2 mol of resorcin to 1 mol of one or more phenols represented by the general formula (i).

In carrying out the production method of the present invention, the proportion of p-tert-butylphenol used as one or more phenols (hereinafter sometimes referred to as phenols) represented by the above general formula (i) is The higher the value, the cheaper the production of the novolak type cocondensate of the present invention can be made, but phenols other than p-tert-butylphenol may be used in combination. Examples of phenols other than p-tert-butylphenol that can be used in combination include o-tert-butylphenol, o-phenylphenol, p-phenylphenol, p-cresol, p-tert-octylphenol, and p-nonylphenol. Examples thereof include phenols having an alkyl group having 1 to 12 carbon atoms or a phenyl group as a substituent. Among these phenols, from the viewpoint of complying with the above-mentioned laws and regulations, phenols having an alkyl group having 1 to 6 carbon atoms or a phenyl group which may have a branch are preferable, and in particular, o-tert-butylphenol, o-phenyl Phenol, p-phenylphenol and p-cresol are preferred. When other phenols are used in combination, the amount of phenols other than p-tert-butylphenol in the total phenols is usually 35 mol% or less, and the price of the other phenols and the novolak type From the viewpoint of the solubility of the condensate in fatty acids having 8 to 32 carbon atoms, it is preferably 20 mol% or less, more preferably 10 mol% or less, and particularly preferably 5 mol% or less.

As the formaldehyde used in the step (1), in addition to gaseous formaldehyde, a formalin that is an aqueous solution of formaldehyde, a compound that can easily generate formaldehyde, such as paraformaldehyde and trioxane can be used. For example, the amount of formaldehyde used is preferably 1 to 3 moles, more preferably 1.5 to 2.5 moles per mole of phenols. By using 1 mol or more, it becomes possible to suppress generation | occurrence | production of a volatile organic compound, and the softening point of the novolak-type cocondensate obtained is lowered more by making the usage-amount 3 mol or less. It becomes possible.

As the base used in the step (1), a base used for producing a usual resol-type condensate such as an alkali metal or alkaline earth metal hydroxide or carbonate, ammonia, amine or the like can be used. . Specific examples of these bases include sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate and the like. Among these bases, sodium hydroxide and potassium hydroxide are preferable. These bases may be used alone or as a mixture of two or more if necessary. These bases can be solid or liquid (aqueous solution or organic solution), but an aqueous solution is preferred because of its reactivity and easy handling. When an aqueous solution is used, the base contained in the aqueous solution is usually 10% to 50% by weight. The base is used in an amount of 0.05 mol or more, preferably 0.05 to 0.8 mol, more preferably 0.2 to 0.5 mol, per mol of phenol. If the amount of the base used is less than 0.05 mol, the number of unreacted monomers increases and the odor or volatile organic compound increases, or the number average molecular weight (Mn) in the gel permeation chromatography (GPC) method is 600 or more. It may be difficult to obtain a resol-type condensate. In addition, when the novolak-type cocondensate with reduced odor is required, the amount of base used is preferably 0.05 mol or more and 0.25 mol or less with respect to 1 mol of phenols. The reason why the odor is reduced when the amount of the base used is 0.25 mol or less is not clear, but it is because side reactions caused by formaldehyde and the base such as the Cannizzaro reaction and the Formose reaction are suppressed. Presumed.

When carrying out step (1), an organic solvent can also be used. As usable organic solvents, for example, aromatic hydrocarbons such as toluene, xylene and ethylbenzene, and ketones having 3 to 7 carbon atoms such as methyl isobutyl ketone are preferably used. These organic solvents may be used alone or in combination as needed. When the organic solvent is used, the amount used is usually 0.4 to 4.0 times by weight with respect to 1 time by weight of phenols. When the reaction is carried out without using an organic solvent, water can be used in place of the organic solvent.

As a method for carrying out step (1), for example, phenols and formaldehyde and, if necessary, an organic solvent are charged into a reactor, then a base is further charged into the reactor, and the base is dissolved or suspended to carry out the reaction. At the time of carrying out the reaction, the reaction solution is appropriately analyzed using a gel permeation chromatograph (GPC), and the reaction is carried out until the number average molecular weight (Mn) of the resol-type condensate in the reaction solution is 600 or more as the standard polystyrene equivalent molecular weight. Need to be implemented. Moreover, the number average molecular weight (Mn) of the resol-type condensate in the reaction solution is usually 1500 or less. If the number average molecular weight (Mn) of the resole-type condensate in step (1) is lower than 600, in the step of reacting with resorcin, which will be described later (step (3)), the swelling of the reaction solution, the decrease in fluidity, Problems that impede industrial implementation, such as non-uniformization, occur, and in order to solve the problems, high temperature conditions or high stirring intensity conditions that are difficult to implement industrially tend to be required. In addition, when water, unreacted phenols, solvents, and the like are reduced from the resulting novolak-type cocondensate after the reaction is performed under the high temperature condition or the high stirring strength condition, the softening point of the cocondensate is 150. In this case, it is unsuitable as an adhesive between the rubber and the reinforcing material used by mixing with the rubber during kneading. In addition, the number average molecular weight of a resol type condensate is determined by the method described in the Example mentioned later.

In order to carry out step (1) and obtain a resol-type condensate having a number average molecular weight (Mn) of 600 or more, the reaction temperature is usually 75 ° C. or higher, preferably 75 to 120 ° C. When the reaction is carried out at a temperature lower than 75 ° C., it tends to be difficult to obtain a resol-type condensate having a number average molecular weight (Mn) of 600 or more. In addition, when implementing reaction in a process (1), it is not necessary to always be 75 degreeC or more, and what is necessary is just to become 75 degreeC or more at any time in this reaction.

Step (2) can be carried out by mixing the reaction solution containing the resol-type condensate obtained in step (1) with the base used in step (1) and an acid equal to or more than the equivalent amount. Examples of the acid used in the step (2) include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid, and organic acids such as formic acid, acetic acid, oxalic acid, and p-toluenesulfonic acid. These acids may be used alone or in combination of two or more, or an aqueous solution of these acids may be used. The amount of the acid used is not less than the equivalent of the base content of the base used in step (1), and preferably 1 to 2 mol per 1 mol of the base content. In step (2), the mixture of the reaction solution containing the resol-type condensate obtained in step (1) and the acid is divided into multiple times, and the total amount of acid used is equivalent to the base used in step (1). You may implement in the form which becomes the above.

When the step (2) is not carried out, the performance as an adhesive used in the rubber processing step such as deteriorating the physical properties of the vulcanized rubber when the resulting novolak type cocondensate is added to the rubber is used. There are cases where it does not fully perform. Furthermore, when reacting with resorcin in step (3), the reaction does not proceed sufficiently, and a large amount of unreacted phenols remain, or when removing unreacted phenols, resorcin, etc. In some cases, coloration or decomposition of the resulting novolak-type cocondensate occurs, resulting in deterioration in quality as an adhesive. Moreover, it becomes possible to reduce the hygroscopic property of the obtained cocondensate by implementing a process (2).

After the step (2), the resol-type condensate is extracted into the organic phase using an organic solvent immiscible with water and water, if necessary, in order to remove unreacted formaldehyde and by-product inorganic salts. In addition, a water washing step of separating unreacted formaldehyde and by-product inorganic salts in the aqueous phase may be performed.

The amount of resorcin used in step (3) needs to be 0.5 to 1.2 mol, preferably 0.5 to 1.2 mol, based on 1 mol of phenol used in step (1). 1.0 mole, more preferably 0.5 to 0.8 mole. When the amount of resorcin used is more than 1.2 mol, a large amount of unreacted resorcin remains, and volatility may be a problem. In addition, novolak cocondensates that are well compatible with stearic acid tend to be difficult to obtain. When the amount of resorcin used is less than 0.5 mol, when the performance as an adhesive used in the rubber processing step is not expressed, the molecular weight of the resulting novolak type cocondensate becomes high, and the softening point is 150 ° C. It may not be the following.

Although step (3) can be carried out without using a solvent, it may be carried out in the presence of 0.2 times by weight or more of the solvent with respect to 1 time by weight of the phenols used in step (1). It is preferable to carry out in the presence of 0.4 to 2.0 times by weight of solvent. It is possible to reduce the content of unreacted resorcin in the obtained novolak-type cocondensate while avoiding polymerization of the obtained novolak-type cocondensate by using a solvent of 0.2 times by weight or more. Become. In addition, when the amount of the solvent used is 2.0 weight times or less, when it is desired to remove the solvent used in the reaction from the cocondensate, the solvent can be removed more efficiently than the cocondensate. Examples of the solvent that can be used in the step (3) include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene, ketones having 3 to 7 carbon atoms such as methyl isobutyl ketone, and ethyl acetate, n-propyl acetate, isopropyl acetate, Examples include ester organic solvents such as n-butyl acetate, isobutyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, ethyl butanoate, and methyl pentanoate. Xylene and n-butyl acetate are preferred. As the solvent used in step (3), the solvent used in the water washing step appropriately performed after step (1) and / or step (2) may be used as it is, or a new solvent may be added as appropriate. Good.

The reaction in the step (3) is usually carried out at 40 to 150 ° C., preferably 100 to 150 ° C. In addition, when the resole-type condensate reacts with resorcin, the reaction rate may be slowed if water is present in the system, so the reaction should be carried out while removing the water produced as a by-product from the reaction. Is preferred.

After the completion of the step (3), the novolak-type cocondensate of the present invention having the characteristics described later can be obtained. The solvent used in the reaction, unreacted phenols, resorcin and the like contained in the novolak-type cocondensate When it is necessary to remove, it can be concentrated and removed by a conventional method (hereinafter, this step may be referred to as a concentration and removal step). When carrying out the concentration removal step, if the internal temperature exceeds 165 ° C., the resulting novolac cocondensate tends to have a softening point of 150 ° C. or higher, making it difficult to use as an adhesive used in rubber processing steps. Or the novolac cocondensate may be colored or decomposed.

<Novolac type cocondensate of the present invention>
The novolak-type cocondensate of the present invention has the following characteristics (a) and (b).
(A) The structural unit derived from the 1 type (s) or 2 or more types of phenols, formaldehyde, and resorcin represented by the said general formula (i) is included.
(B) The structural unit derived from phenols contains 65 mol% or more of a structural unit derived from p-tert-butylphenol. The structural unit derived from phenols preferably contains a structural unit derived from p-tert-butylphenol in an amount of 80 mol% or more, more preferably 90 mol% or more.

The novolak-type cocondensate of the present invention usually contains 1 to 2 moles of a formaldehyde-derived structural unit (methylene group and / or dimethylene ether group) with respect to 1 mole of the total amount of structural units derived from phenols. The ratio of these structural units can be confirmed, for example, by analyzing a novolak-type cocondensate using ¹ H-NMR. Specifically, the produced novolak type cocondensate was washed with a solvent such as water to remove unreacted monomers such as unreacted resorcin contained from the novolak type cocondensate, and then analyzed by ¹ H-NMR. Of the obtained analysis results, a method of determining the ratio from the proton integral value derived from each constituent unit is exemplified.

Furthermore, the novolak-type cocondensate of the present invention has the following characteristics (c), (d) and (e).
(C) The number average molecular weight (Mn) in the gel permeation chromatograph (GPC) method is 750 or more.
(D) Softening point is 80 to 150 ° C.
(E) The structural unit derived from resorcin is 0.80 mol or less per 1 mol of the structural unit derived from one or more phenols represented by the general formula (i).

The novolak type cocondensate of the present invention has a number average molecular weight (Mn) in a gel permeation chromatograph (GPC) method of 750 or more, preferably 1000 or more as a standard polystyrene equivalent molecular weight. If the number average molecular weight is lower than 750, blocking may occur during storage. The number average molecular weight of the novolak-type cocondensate is determined by the method described in Examples described later. The number average molecular weight is preferably 3000 or less, and more preferably 2000 or less. By setting the number average molecular weight to 3000 or less, it becomes possible to further reduce the softening point of the novolak type cocondensate.

The novolak cocondensate of the present invention has a softening point of 80 ° C or higher, preferably 90 ° C or higher, and 150 ° C or lower, preferably 140 ° C or lower. When the softening point is higher than 150 ° C., when used as an adhesive in a rubber processing step, the softening point does not sufficiently disperse within the rubber and the adhesive performance tends not to be exhibited sufficiently. Further, when the softening point is lower than 80 ° C., blocking is likely to occur during storage. Note that the softening point of the novolak cocondensate of the present invention is in the above range even when used as an adhesive in a rubber processing step after mixing with a softening agent by a method described later and forming a resin composition. It is preferable.

In the novolak-type cocondensate of the present invention, the constituent unit derived from resorcin is 0.80 mol or less, preferably 0.30 to 0.80 mol, more preferably 0.8. 30 to 0.70 mol is contained. When the number of resorcin-derived structural units is more than 0.80 mol, the hygroscopicity is increased, and the co-condensate is blocked when stored, and the co-condensate is used in a rubber processing step. When used as a rubber, problems such as foaming of rubber are likely to occur. Also, when the constituent unit derived from resorcin is more than 0.80 mol, when the cocondensate is melted, it has thixotropy or becomes a high-viscosity liquid, resulting in poor fluidity, pelletization, flaking, etc. May be difficult to form or may not be compatible with fatty acids having 8 to 32 carbon atoms. Moreover, when it is less than 0.30 mol, the performance as an adhesive may not be expressed. The ratio of the structural unit derived from resorcin can be determined by the method described in Examples described later.

Further, when the novolak type cocondensate of the present invention has the following characteristic (f), the compatibility with fatty acids having 8 to 32 carbon atoms is improved.
(F) A component (oligomer 2) having a peak top molecular weight of 700 to 520 in an area percentage of 1 to 10% and a peak top molecular weight of 430 to 320 (oligomer 2) in a gel permeation chromatograph (GPC) method. The area percentage is 0.01 to 2%.

Whether or not it has the above-described characteristics can be confirmed by analysis using a gel permeation chromatograph (GPC) under the conditions described later.

Furthermore, when the novolak-type cocondensate of the present invention is not colored brown, it tends to be a cocondensate with reduced odor. Specifically, when the spectral transmittance at a wavelength of 610 nm of a solution obtained by dissolving 2.0 g of the cocondensate of the present invention in 20 mL of tetrahydrofuran is 80% or more, it tends to be a cocondensate with reduced odor. The spectral transmittance at a wavelength of 610 nm is determined by the method described in the examples described later. Although the relationship between coloring and odor is not clear, it is presumed that there is a correlation between coloring and odor because some coloring components affect the odor.

The content of unreacted resorcin contained in the novolak-type cocondensate of the present invention is preferably 8% by weight or less. By using the novolac type cocondensate as it is as an adhesive in the rubber processing step, it is possible to suppress transpiration of resorcin at the time of rubber kneading, and this is preferable in terms of the working environment. When a novolac cocondensate is mixed with a softener and used as a resin composition, the unreacted resorcin content should be 10% by weight or less, depending on the mixing ratio of the novolak cocondensate and the softener. Is preferred. The content of unreacted phenols (one or more phenols represented by the above general formula (i) used as a raw material) contained in the novolak-type cocondensate of the present invention is 3% by weight or less. It is preferable that the content is 1% by weight or less. By setting the content of unreacted phenols to 3% by weight or less, it is possible to reduce harmful effects on humans and ecosystems. In addition, the content of volatile organic compounds (such as a solvent used in the production as necessary) contained in the novolak type cocondensate of the present invention is preferably 5% by weight or less from the viewpoint of environment. More preferably, it is less than or equal to weight percent. The volatile organic compound does not include the aforementioned unreacted resorcin and unreacted phenols.

<Resin composition>
Subsequently, a resin composition containing the novolak type cocondensate of the present invention and a softening agent will be described. (Hereinafter, the resin composition containing the novolak-type cocondensate of the present invention and a softener may be simply referred to as a resin composition.)

The softening agent used in the present invention may be any substance that is compatible with the novolak-type cocondensate of the present invention and can reduce the softening point of the resulting resin composition. Examples of such substances include solids having a low softening point such as coumarone resin and liquids such as cashew nut shell liquid (CNSL), which are generally used as softeners for novolak-type cocondensates. Furthermore, the novolak-type cocondensate obtained by the production method of the present invention is compatible with fatty acids having 8 to 32 carbon atoms such as stearic acid which is widely used as a vulcanization aid in the rubber processing step. Therefore, fatty acids having 8 to 32 carbon atoms can be used as a softening agent. Note that the novolak type cocondensate obtained by a conventionally known production method irrespective of the production method of the present invention is not compatible with fatty acids having 8 to 32 carbon atoms, and separation of the resin layer and the oil layer occurs.

These softeners may be used alone or as a mixture of two or more if necessary. In particular, a resin composition using a fatty acid having 8 to 32 carbon atoms, particularly stearic acid, as a softening agent can reduce its softening point without adding a substance not normally used in the rubber processing process as a softening agent. For this reason, it can be suitably used for applications in which substances added separately as a softening agent are problematic (for example, rubber in which the softening agent reacts with other components contained in the rubber).

Cashew nut shell liquid is a natural plant liquid obtained from cashew nut shells. Cashew nut shell liquid is a mixture composed of phenol derivatives having saturated or unsaturated hydrocarbon side chains. In particular, anacardic acid, cardanol, cardol (also referred to as curdle), and methyl cardol (also referred to as methyl curdle) are mainly included as its components. As a method for preparing the cashew nut shell liquid, there are a heating method and a solvent extraction method. Usually, an industrial cashew nut shell liquid is prepared by heat treatment. Anacardic acid is decarboxylated by this heat treatment and converted to cardanol, so cardanol, cardol, and methyl cardol are the main components. Therefore, the composition ratio (wt% ) Are cardanol (75-85%), cardol (15-20%), methyl cardol (1-5%). In addition, the cashew nut shell liquid in the present invention is obtained by appropriately purifying each component contained in the liquid by separating and purifying the cashew nut shell liquid, or adding another component to the cashew nut shell liquid and polymerizing a part thereof. Also included is a cashew nut shell polymer.

As commercially available cashew nut shell liquid, for example, cashew liquid products (CNSL, LB-7000, LB-7250, CD-5L) manufactured by Tohoku Kako Co., Ltd., TAN HOA HOP PHAT Co. , Ltd. CNSL and the like. These cashew nut shell liquids may be used alone or in combination of two or more as required.

Examples of the fatty acids having 8 to 32 carbon atoms include saturated or unsaturated fatty acids having 8 to 32 carbon atoms, or metal salts thereof. Specifically, examples of the saturated fatty acid include caprylic acid (octanoic acid), pelargonic acid, capric acid, undecyl acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Examples include oleic acid and undecenoic acid. These fatty acids may be used alone or in combination of two or more as required. Of these fatty acids, stearic acid, palmitic acid, myristic acid, lauric acid, and behenic acid are preferable from the viewpoints of price and availability. Further, stearic acid is particularly preferable because it is a common organic acid as an additive to rubber.

Specific examples of stearic acid used in the present invention include, for example, NOF Corporation bead stearic acid Tsubaki (C18: 63%, C16: 32%), bead stearic acid Sakura (C18: 66%, C16: 31%), etc. Is mentioned.

The content of the softening agent contained in the resin composition is 5% by weight or more, preferably 10% by weight or more, and 40% by weight or less, preferably 30% by weight or less based on the total amount of the resin composition. By setting the content to 40% by weight or less, it becomes possible to reduce the blocking of the resin composition and the decrease in performance as an adhesive for rubber. By making the content 5% by weight or more, the softening point Is sufficiently exerted.

When the resin composition of the present invention is kneaded into rubber at a normal kneading temperature of about 170 ° C., the softening point of the resin composition is sufficient if it is 150 ° C. or less, but it suppresses the evaporation of resorcin during kneading. For the purpose of kneading at a low temperature of 100 to 130 ° C., a problem of poor dispersibility may occur unless the softening point is 120 ° C. or lower, which is lower than the kneading temperature. Performance may not be fully demonstrated. Moreover, when the softening point of a resin composition is lower than 80 degreeC, it may block during storage and is unpreferable.

Similarly to the above-described novolak-type cocondensate of the present invention, when the resin composition of the present invention is not colored brown, a resin composition with reduced odor tends to be obtained. Specifically, when the spectral transmittance at a wavelength of 610 nm of a solution obtained by dissolving 2.0 g of the resin composition of the present invention in 20 mL of tetrahydrofuran is 80% or more, a resin composition with reduced odor tends to be obtained. The spectral transmittance at a wavelength of 610 nm is determined by the method described in the examples described later.

The content of unreacted resorcin contained in the resin composition is preferably 8% by weight or less. When the content is 8% by weight or less, it is possible to suppress transpiration of resorcin at the time of rubber kneading, which is preferable in terms of working environment. The content of unreacted phenols contained in the resin composition is preferably 3% by weight or less, and more preferably 1% by weight or less. By setting the content of unreacted phenols to 3% by weight or less, it is possible to reduce harmful effects on humans and ecosystems. In addition, the content of volatile organic compounds (such as a solvent used in the production as necessary) contained in the resin composition is preferably 5% by weight or less, and 3% by weight or less from the viewpoint of the environment. It is more preferable. The volatile organic compound does not include the aforementioned unreacted resorcin and unreacted phenols.

The above-mentioned resin composition can be obtained by mixing the novolak-type cocondensate of the present invention obtained by the above-described methods (1), (2) and (3) with a softening agent. After mixing the softening agent or before mixing the softening agent, if necessary, a concentration removal step for removing the solvent used in the reaction, unreacted p-tert-butylphenol, resorcin, etc. may be performed. .

When the softener contained in the resin composition is a fatty acid having 8 to 32 carbon atoms, when the resole-type condensate and resorcin are reacted (step (3)), the reaction is saturated with 8 to 32 carbon atoms or You may manufacture the resin composition of this invention by implementing in unsaturated fatty-acid presence. By carrying out step (3) in the presence of a saturated or unsaturated fatty acid having 8 to 32 carbon atoms, a resin composition having a small amount of residual resorcin and a relatively low softening point of 80 to 120 ° C. can be easily obtained. be able to. When using a saturated or unsaturated fatty acid having 8 to 32 carbon atoms in step (3), the amount used is usually 15 to 40 parts by weight, preferably 100 parts by weight of the total amount of the resole-type condensate and resorcin. Is 15 to 35 parts by weight, more preferably 18 to 32 parts by weight.

<Rubber composition>
Next, the rubber composition containing the novolak type cocondensate and / or the resin composition according to the present invention will be described in detail.

The rubber composition of the present invention includes the above-described novolak-type cocondensate and / or resin composition and a rubber component, and typically includes the novolak-type cocondensate and / or resin composition, rubber component, and filling. It can be obtained by kneading an agent, sulfur and a methylene donor compound. A vulcanization accelerator, zinc oxide, and an organic cobalt compound can be kneaded together with the above-described components.

The novolak-type cocondensate and / or resin composition of the present invention is used, for example, in the range of 0.5 to 10 parts by weight per 100 parts by weight of the rubber component. In particular, the range of 1 to 5 parts by weight is preferable. When the amount is less than 0.5 parts by weight, it does not usefully act as an adhesive between the reinforcing material and the rubber. When the amount is more than 10 parts by weight, there is no problem in the above effect, but the effect corresponding to the addition amount does not appear and economically It is not preferable.

As rubber components, natural rubber, epoxidized natural rubber, deproteinized natural rubber and other modified natural rubber, polyisoprene rubber (IR), styrene-butadiene copolymer rubber (SBR), polybutadiene rubber (BR), acrylonitrile -Various synthetic rubbers such as butadiene copolymer rubber (NBR), isoprene / isobutylene copolymer rubber (IIR), ethylene / propylene-diene copolymer rubber (EPDM), halogenated butyl rubber (HR), etc. are exemplified. Highly unsaturated rubbers such as rubber, styrene / butadiene copolymer rubber and polybutadiene rubber are preferably used. Particularly preferred is natural rubber. It is also effective to combine several rubber components such as a combination of natural rubber and styrene / butadiene copolymer rubber, a combination of natural rubber and polybutadiene rubber.

Examples of natural rubber include natural rubber of grades such as RSS # 1, RSS # 3, TSR20, and SIR20. As the epoxidized natural rubber, those having a degree of epoxidation of 10 to 60% by mole are preferable, and examples thereof include ENR25 and ENR50 manufactured by Kumpoulangrie. As the deproteinized natural rubber, a deproteinized natural rubber having a total nitrogen content of 0.3% by weight or less is preferable. As the modified natural rubber, a modified natural rubber containing a polar group obtained by reacting natural rubber with 4-vinylpyridine, N, N-dialkylaminoethyl acrylate (for example, N, N-diethylaminoethyl acrylate), 2-hydroxyacrylate or the like in advance. Rubber is preferably used.

Examples of the SBR include emulsion polymerization SBR and solution polymerization SBR described in pages 210 to 211 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. In particular, solution polymerization SBR is preferably used, and more preferably,
Solution polymerization SBR having a molecular end modified with 4,4′-bis- (dialkylamino) benzophenone such as “Nipol (registered trademark) NS116” manufactured by Nippon Zeon Co., Ltd.
Solution polymerized SBR having molecular ends modified with tin halide compounds such as “SL574” manufactured by JSR,
Commercial products of silane-modified solution polymerization SBR, such as “E10” and “E15” manufactured by Asahi Kasei Co., Ltd.
Molecular terminals using any of lactam compounds, amide compounds, urea compounds, N, N-dialkylacrylamide compounds, isocyanate compounds, imide compounds, silane compounds having an alkoxy group (trialkoxysilane compounds, etc.), and aminosilane compounds alone Solution polymerization SBR having any of nitrogen, tin, and silicon at the molecular ends obtained by modifying
Two or more compounds selected from lactam compounds, amide compounds, urea compounds, N, N-dialkylacrylamide compounds, isocyanate compounds, imide compounds, silane compounds having an alkoxy group (trialkoxysilane compounds, etc.) and aminosilane compounds ( A silane compound having a tin compound and an alkoxy group, a silane compound having an alkyl acrylamide compound and an alkoxy group, etc. Solution polymerization SBR with elements
Is used.

Examples of BR include solution polymerization BR such as high cis BR having 90% or more of cis 1,4 bond and low cis BR having cis bond of about 35%, and low cis BR having high vinyl content is preferably used. It is done. More preferably,
Zeon modified BR such as “Nipol (registered trademark) BR 1250H” manufactured by Nippon Zeon,
4,4′-bis- (dialkylamino) benzophenone, tin halide compound, lactam compound, amide compound, urea compound, N, N-dialkylacrylamide compound, isocyanate compound, imide compound, silane compound having an alkoxy group (tri Solution-polymerized BR having an element of nitrogen, tin, or silicon at the molecular terminal obtained by modifying the molecular terminal by using any one of an alkoxysilane compound and the like, and an aminosilane compound alone,
4,4′-bis- (dialkylamino) benzophenone, tin halide compound, lactam compound, amide compound, urea compound, N, N-dialkylacrylamide compound, isocyanate compound, imide compound, silane compound having an alkoxy group (tri The molecular terminal is modified by using two or more compounds selected from an alkoxysilane compound and an aminosilane compound (a silane compound having a tin compound and an alkoxy group, or a silane compound having an alkylacrylamide compound and an alkoxy group). Solution polymerization BR having two or more elements selected from nitrogen, tin and silicon at the molecular ends obtained
Is used. These BRs are usually used in blends with natural rubber.

The rubber component preferably contains natural rubber, and the proportion of natural rubber in the rubber component is preferably 70% by weight or more.

Examples of the filler include carbon black, silica, talc, clay, aluminum hydroxide, titanium oxide and the like which are usually used in the rubber field, but carbon black and silica are preferably used, and carbon black is particularly preferable. Preferably used. Examples of the carbon black include those described in page 494 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. HAF (High Ablation Furnace), SAF (Super Ablation Furnace), ISAF (Intermediate). Carbon black such as SAF), FEF (Fast Extraction Furnace), MAF (Medium Abrasion Furnace), GPF (General Purpose Furnace), SRF (Semi-Reinforming Furnace) and the like are preferable. A carbon black having a CTAB surface area of 40 to 250 m ² / g, a nitrogen adsorption specific surface area of 20 to 200 m ² / g, and a particle diameter of 10 to 50 nm is preferably used for the tire tread rubber composition, and the CTAB surface area of 70 to 180 m ² / g. A certain carbon black is more preferable, and examples thereof include N110, N220, N234, N299, N326, N330, N330T, N339, N343, N351 and the like in the ASTM standard. Also preferred is a surface-treated carbon black in which 0.1 to 50% by weight of silica is adhered to the surface of the carbon black. Furthermore, it is also effective to combine several kinds of fillers such as a combination of carbon black and silica.

Examples of the silica include silica having a CTAB specific surface area of 50 to 180 m ² / g and a nitrogen adsorption specific surface area of 50 to 300 m ² / g. “AQ”, “AQ-N” manufactured by Tosoh Silica Co., Ltd., Degussa "Ultrasil (registered trademark) VN3", "Ultrasil (registered trademark) 360", "Ultrasil (registered trademark) 7000", Rhodia "Zeosil (registered trademark) 115GR", "Zeosil (registered trademark)" Commercially available products such as “1115MP”, “Zeosil (registered trademark) 1205MP”, “Zeosil (registered trademark) Z85MP”, “Nippal (registered trademark) AQ” manufactured by Nippon Silica Co., Ltd. are preferably used. In general, when silica is used as a filler, bis (3-triethoxysilylpropyl) tetrasulfide (“Si-69” manufactured by Degussa) or bis (3-triethoxysilylpropyl) disulfide (“Degussa” Si-75 "), bis (3-diethoxymethylsilylpropyl) tetrasulfide, bis (3-diethoxymethylsilylpropyl) disulfide, and octanethioic acid S- [3- (triethoxysilyl) propyl] ester (general electronic Adding one or more silane coupling agents selected from the group consisting of “NXT silane” manufactured by Silicones Co., Ltd.) and other compounds having functional groups such as silicon or elements that can be bonded to silica or alkoxysilane. Is preferred.

Examples of the aluminum hydroxide include aluminum hydroxide having a nitrogen adsorption specific surface area of 5 to 250 m ² / g and a DOP oil supply amount of 50 to 100 ml / 100 g.

The amount of the filler used is not particularly limited, but is preferably in the range of 10 to 120 parts by weight per 100 parts by weight of the rubber component. Particularly preferred is 30 to 70 parts by weight.

The filler preferably contains carbon black, and the proportion of carbon black in the filler is preferably 70% by weight or more.

Examples of the sulfur component include powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur. Usually, powdered sulfur is preferred, and insoluble sulfur is preferred when used for tire members having a large amount of sulfur such as tire belt members. The amount of sulfur component used is not particularly limited, but is preferably in the range of 1 to 10 parts by weight per 100 parts by weight of the rubber component. In the case of a tire belt member or the like, the range of 5 to 10 parts by weight is preferable.

Examples of vulcanization accelerators include thiazole vulcanization accelerators described on pages 412 to 413 of Rubber Industry Handbook <Fourth Edition> (issued by the Japan Rubber Association on January 20, 1994), Examples thereof include sulfenamide vulcanization accelerators and guanidine vulcanization accelerators.

Specifically, for example, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS), N, N-dicyclohexyl-2 -Benzothiazolylsulfenamide (DCBS), 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), diphenylguanidine (DPG). Among them, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS), N, N-dicyclohexyl-2-benzothiazolylsulfur A combination of phenamide (DCBS) or dibenzothiazyl disulfide (MBTS) and diphenylguanidine (DPG) is preferred.

The amount of the vulcanization accelerator used is not particularly limited, but is preferably in the range of 0.5 to 3 parts by weight per 100 parts by weight of the rubber component. In particular, the range of 0.5 to 1.2 parts by weight is more preferable.

The amount of zinc oxide used is not particularly limited, but is preferably in the range of 3 to 15 parts by weight per 100 parts by weight of the rubber component. In particular, the range of 5 to 10 parts by weight is more preferable.

Examples of the methylene donor compound include those commonly used in the rubber industry such as hexamethylenetetramine, hexakis (methoxymethyl) melamine, pentakis (methoxymethyl) methylolmelamine, tetrakis (methoxymethyl) dimethylolmelamine. Among them, hexakis (methoxymethyl) melamine alone or a mixture containing it as a main component is preferable. These methylene donor compounds can be used alone or in combination of two or more, and the blending amount is preferably in the range of about 0.5 to 4 parts by weight with respect to 100 parts by weight of the rubber component. A range of about 3 parts by weight is more preferable.

Examples of the organic cobalt compound include acid cobalt salts such as cobalt naphthenate and cobalt stearate, and fatty acid cobalt / boron complex compounds (for example, trade name “Manobond C (registered trademark)” manufactured by Rhodia). . The amount of the organic cobalt compound used is preferably in the range of 0.05 to 0.4 parts by weight in terms of cobalt content with respect to 100 parts by weight of the rubber component.

The rubber composition of the present invention can be kneaded with various compounding agents conventionally used in the rubber field. Examples of such compounding agents include anti-aging agents, oils, retarders, peptizers, and stearic acid.

Examples of the anti-aging agent include those described on pages 436 to 443 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Among them, N-phenyl-N′-1,3-dimethylbutyl-p-phenylenediamine (6PPD), reaction product of aniline and acetone (TMDQ), poly (2,2,4-trimethyl-1,2-) dihydro Quinoline) (“Antioxidant FR” manufactured by Matsubara Sangyo Co., Ltd.), synthetic wax (paraffin wax, etc.) and vegetable wax are preferably used.

Oils include process oils and vegetable oils. Examples of the process oil include paraffinic process oil, naphthenic process oil, and aromatic process oil.

Examples of the retarder include phthalic anhydride, benzoic acid, salicylic acid, N-nitrosodiphenylamine, N- (cyclohexylthio) -phthalimide (CTP), sulfonamide derivatives, diphenylurea, bis (tridecyl) pentaerythritol-diphosphite, etc. N- (cyclohexylthio) -phthalimide (CTP) is preferably used.

The rubber composition containing the novolak-type cocondensate and / or resin composition of the present invention can be obtained, for example, by the following method.

(A) Step of kneading filler and rubber component Kneading of the filler and rubber component can be performed using a closed kneading apparatus such as a Banbury mixer. Such kneading usually involves heat generation, and the temperature at the end of kneading is preferably in the range of 140 ° C. to 180 ° C., and more preferably in the range of 150 ° C. to 170 ° C. The kneading time is about 5 to 10 minutes.

(B) Step of kneading the kneaded product obtained in step (A), sulfur component and vulcanization accelerator Kneading of the kneaded product obtained in step (A), sulfur component and vulcanization accelerator is, for example, A closed kneading apparatus such as a Banbury mixer or an open roll can be used. The temperature of the kneaded product at the end of kneading is preferably 30 ° C. to 100 ° C., and more preferably 60 ° C. to 90 ° C. The kneading time is usually about 5 to 10 minutes.

Since the novolak cocondensate and / or resin composition of the present invention has a low softening point, it can be added in the step (A) or (B), but is preferably added in the step (A).

When using zinc oxide, anti-aging agent, oil, fatty acids, and peptizer, these are preferably added in the step (A). When using a retarder, it is preferable to add at the process of (B).

The rubber composition containing the novolak-type cocondensate and / or resin composition of the present invention thus obtained is particularly effective in vulcanization adhesion with a reinforcing material. Examples of the reinforcing material include organic fibers such as nylon, rayon, polyester, and aramid, and steel cords such as a brass-plated steel cord and a galvanized steel cord. Among them, the rubber composition of the present invention is particularly effective in vulcanization adhesion with a steel cord plated with brass.

A rubber composition containing the novolac-type cocondensate and / or resin composition of the present invention is molded together with a reinforcing material, and a rubber product in which the rubber and the reinforcing material are firmly bonded can be obtained through a vulcanization process. . The vulcanization step is preferably performed at 120 ° C to 180 ° C. The vulcanization step is performed at normal pressure or under pressure.

Hereinafter, the present invention will be described more specifically by showing examples, comparative examples, and reference examples (hereinafter also referred to as examples). The present invention is not limited by these examples. In addition, unless otherwise specified, the content of each component, the amount of residual solvent, and the amount of unreacted monomer described in the Examples, etc. The content of the oligomer component is an area percentage. Moreover, various measurements in each Example etc. were implemented as follows.

[1] Gel permeation chromatograph (GPC) analysis conditions Equipment used: HLC-8220GPC (manufactured by Tosoh Corporation)
Detector: RI (differential refraction) detector Column: TSK guard column SUPER HZ-L (manufactured by Tosoh Corporation)
+ TSK-GEL SUPER HZ1000 (4.6mmφ × 150mm)
+ TSK-GEL SUPER HZ2500 (4.6mmφ × 150mm)
+ TSK-GEL SUPER HZ4000 (4.6mmφ × 150mm)
Column temperature: 40 ° C
Injection volume: 10 μL
Carrier and flow rate: tetrahydrofuran 0.35 mL / min
Standard substance for obtaining converted molecular weight (preparation of GPC calibration curve): 1,1-bis (4-hydroxyphenyl) cyclohexane (FW268) and phenol (FW94) added to TSK-GEL standard polystyrene kit (PS-oligomer kit) A calibration curve was created.
Sample preparation: about 0.02 g of the cocondensate or resin composition and reaction mixture was dissolved in 10 mL of tetrahydrofuran.

Based on the results obtained by the GPC analysis, the average molecular weight of the resol-type condensate, the average molecular weight of the novolac-type cocondensate and the resin composition, and the content of each oligomer component contained in the novolak-type cocondensate and the resin composition (Area percentage) was calculated as follows.

(A) Weight average molecular weight (Mw) and number average molecular weight (Mn) of the resol type condensate
The multimodal peak obtained by the measurement of the resol type condensate was handled as a lump, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated. In calculating the average molecular weight of the resol-type condensate, when an organic solvent was used during the production, the peak corresponding to the organic solvent was excluded.

(B) Weight average molecular weight (Mw) and number average molecular weight (Mn) of the novolak-type cocondensate
The multimodal peak obtained by the measurement of the novolak-type cocondensate was handled as a group, and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated. In calculating the average molecular weight of the novolak-type cocondensate, the peak derived from the unreacted monomer (phenols, resorcin) and the peak corresponding to the organic solvent were excluded when the organic solvent was used during the production. .

(C) Weight average molecular weight (Mw) and number average molecular weight (Mn) of the resin composition
A multimodal peak obtained by measurement of the resin composition was handled as a group, and a weight average molecular weight (Mw) and a number average molecular weight (Mn) were calculated. In calculating the average molecular weight of the resin composition, when an organic solvent was used during production, the peak corresponding to the organic solvent was excluded.

(D) Content of oligomer component A multi-peak is separated from each peak valley from the GPC chart obtained when measuring the average molecular weight of the novolak-type cocondensate, and each peak top molecular weight (hereinafter, Examples and the like). And the peak area percentage (%) was calculated. In addition, when calculating the content (area percentage) of the oligomer component, when an organic solvent was used during the production, the peak corresponding to the organic solvent was excluded.

[2] Measurement of unreacted monomer and volatile organic compound content The unreacted monomer and volatile organic compound content were determined by gas chromatography based on the following conditions.
Equipment used: Gas chromatograph GC-2014 manufactured by Shimadzu Corporation
Column: Glass column outer diameter 5 mm x inner diameter 3.2 mm x length 3.1 m
Filler: Filler Silicone OV-17 10% Chromosorb WHP 80/100 mesh, max. temp. 340 ° C
Column temperature: 80 ° C → 280 ° C
Vaporization chamber temperature: 250 ° C
Detector temperature: 280 ° C
Detector: FID
Carrier: N ₂ (40 ml / min)
Combustion gas: Hydrogen (60 kPa), Air (60 kPa)
Injection volume: 2 μL
Sample preparation conditions: Resol type condensate, novolak type cocondensate, or 2.0 g of resin composition is dissolved in 10 mL of standard solution (acetone solution of anisole (about 1 g / 200 mL)). Unreacted monomers and volatile organic compounds As for the novolak type cocondensate or resin composition having a content of 0.1% or less, 2.0 g of a sample was dissolved in 10 mL of anisole in acetone (about 1 g / 200 mL) and analyzed additionally under the above conditions.
Quantitative method: Internal standard method (GC-IS method).

Further, the pure content (% by weight, hereinafter referred to as%) of the resol-type condensate described in each example etc. is determined by quantifying the amount of organic solvent contained in the solution containing the resol-type condensate by the above method. The calculation was made assuming that all components other than the organic solvent were resol-type condensates.

[3] Measurement of softening point Measured by a method based on JIS-K2207.

[4] Ratio of each structural unit of co-condensate or resin composition ¹ H-NMR analysis was performed by a method based on the following conditions.
Equipment: “JMN-ECS” (400 MHz) manufactured by JEOL Ltd.
Solvent: Deuterium-substituted dimethyl sulfoxide 0.03% (v / v) with TMS ampoule Sample: Approximately 3 mg dissolved in 0.75 mL of solvent Preparation of sample for analysis: Included in novolak cocondensate or resin composition In order to remove unreacted monomers such as unreacted resorcin, the cocondensate was previously washed with water by the following method and subjected to ¹ H-NMR analysis.

30 g of the co-condensate or resin composition obtained in each example and the like and roughly crushed to 5 mm square or less with a mortar and 60 g of water were weighed into a 200 mL three-necked separable flask. Next, oxalic acid was added until the pH of the aqueous layer became 5 to 7, and after raising the internal temperature to about 100 ° C., the mixture was refluxed and mixed at the same temperature for 30 minutes while stirring with a mechanical stirrer. Then, stirring was stopped and the aqueous layer was quickly removed at the same internal temperature (water washing 1). Subsequently, 60 g of water was added again, the temperature was raised to about 100 ° C., and the mixture was refluxed and mixed at the same temperature for 30 minutes while stirring with a mechanical stirrer. After 30 minutes of reflux mixing, the aqueous layer was similarly removed (water washing 2). Thereafter, water was distilled off at an internal temperature of 140 to 150 ° C. under reduced pressure, and the cocondensate or the resin composition was dried by further reducing the pressure to 16 kPa while maintaining the same temperature.

Assignment of ¹ H-NMR analysis results, etc. Chemical shift of each component: Tetramethylsilane was used as a reference (0 ppm), and the peaks shown in the following values were taken as the peaks of the respective components.
Proton of p-tert-butyl group derived from p-tert-butylphenol: 1.00 to 1.15 ppm
Proton of methylene group derived from formaldehyde: 3.4 to 4.0 ppm
Proton of o-tert-butyl group derived from o-tert-butylphenol: 1.25 to 1.35 ppm
Proton of o-phenyl group derived from o-phenylphenol: 7.2 to 7.5 ppm
Proton of p-phenyl group derived from p-phenylphenol: 7.2 to 7.5 ppm

In addition, since the protons of the phenolic hydroxyl group derived from resorcin were difficult to be assigned separately, the protons derived from all phenolic hydroxyl groups: from the integrated value of 7.80 to 9.80 ppm, derived from phenols other than resorcin The integral value of two phenolic hydroxyl groups derived from resorcin was calculated by subtracting the integral value of protons derived from one phenolic hydroxyl group.

Specifically, for example, in a novolak-type cocondensate containing p-tert-butylphenol and o-phenylphenol as phenols, protons derived from all phenolic hydroxyl groups: from the integrated value of 7.80 to 9.80 ppm, p- Two phenolic hydroxyl groups derived from resorcin by subtracting the integral value of protons derived from one phenolic hydroxyl group derived from tert-butylphenol and the integral value of protons derived from one phenolic hydroxyl group derived from o-phenylphenol The integral value of was calculated.

In addition, about the component ratio described in the Example etc., it is a ratio based on the following references | standards.
Resorcin: Ratio when the structural unit derived from p-tert-butylphenol is 1 (mole times)
o-Phenylphenol: Ratio when the structural unit derived from p-tert-butylphenol is 1 (mole times)
o-tert-Butylphenol: Ratio when the structural unit derived from p-tert-butylphenol is 1 (mole times)
p-Phenylphenol: Ratio (molar ratio) when the structural unit derived from p-tert-butylphenol is 1.
In Examples where p-tert-butylphenol and other phenols were used in combination, when describing the structural unit of resorcin, the ratio when the structural unit derived from all phenols was set to 1 in parentheses was also shown. .

[5] Transmittance measurement The transmittance at a wavelength of 610 nm of a solution obtained by dissolving the cocondensate or the resin composition in 20 mL of tetrahydrofuran was measured under the following conditions.
Apparatus: Color difference meter (“SE6000” manufactured by Nippon Denshoku Industries Co., Ltd.)
Measurement temperature: 25 ° C
Measurement method: 2.0 g of the cocondensate or resin composition is dissolved in 20 mL of tetrahydrofuran to prepare a solution, and a rectangular quartz cell (optical path length: 10 mm) is used, and the spectral transmittance of the solution is adjusted to a wavelength of 380- Measured over a range of 780 nm. The spectral transmittance of tetrahydrofuran used for dissolution was 100% at a wavelength of 610 nm.

1. Production and physical properties of cocondensates and resin compositions

<Example 1>
To a four-necked separable flask equipped with a reflux condenser and a thermometer, 180.0 g (2.22 mol) of formalin having a purity of 37% and 180.0 g (1.20 mol) of p-tert-butylphenol were sequentially added. Thereafter, the internal temperature was raised to 40 ° C., 80.0 g (0.48 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C. and reacted at that temperature for 1 hour. After the reaction, the reaction mixture was analyzed by GPC. The molecular weight of the resol-type condensate was weight average molecular weight (Mw) = 370, number average molecular weight (Mn) = 317 (hereinafter, weight average molecular weight was Mw, number average molecular weight was (Abbreviated as Mn).
Thereafter, the temperature was further raised to an internal temperature of 82 ° C., and the reaction was conducted at the same temperature for 9 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 1514 and Mn = 943.
After completion of the reaction, 135.0 g of methyl isobutyl ketone (hereinafter also referred to as MIBK), 72.0 g (0.220 mol) of 30% sulfuric acid, and 3.02 g (0.024 mol) of oxalic acid dihydrate were added for 0.1 hour. The mixture was allowed to stand after stirring, and the lower aqueous layer was removed. The resol-type condensate in the four-neck separable flask was 374 g (pure content 60%).
Subsequently, 79.2 g (0.72 mol) of resorcin was added, the temperature was raised to an internal temperature of 90 ° C., the pressure was reduced slightly (internal pressure: 92 kPa), and then the reaction was performed while refluxing and dehydrating at an internal temperature of 90 to 119 ° C. for 2 hours. went. Subsequently, the pressure was restored with nitrogen, and the reaction was further carried out under reflux at 250 to 135 ° C. for 2 hours under normal pressure.
After the reaction, MIBK was distilled off under normal pressure at an internal temperature of 142 to 145 ° C., and then reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C., whereby MIBK was further distilled off and a yellow novolak type co-polymer was obtained. 268 g of condensate was obtained. Table 3 shows the physical properties and the like of the obtained novolak type cocondensate.

<Example 2>
A four-necked separable flask equipped with a reflux condenser and a thermometer was charged with 144.9 g (4.44 mol) of paraform with a purity of 92%, 360.0 g (2.40 mol) of p-tert-butylphenol, and 252.0 g of toluene. Added in order. Thereafter, the internal temperature was raised to 40 ° C., 160.0 g (0.96 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 66 ° C., and the reaction was carried out at the same temperature for 1 hour. When the reaction mixture was analyzed by GPC after the reaction, the molecular weight of the resol-type condensate was Mw = 273 and Mn = 258. Next, the temperature was raised to 88 ° C. and the reaction was carried out at the same temperature for 4 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 1586 and Mn = 998.
After completion of the reaction, 142.0 g (0.435 mol) of 30% sulfuric acid and 6.04 g (0.048 mol) of oxalic acid dihydrate were added, and the mixture was allowed to stand for 0.2 hours, and the lower aqueous layer was removed. The resol-type condensate in the four-neck separable flask was 661 g (pure content 61%).
Subsequently, 171.5 g (1.56 mol) of resorcin was added, the temperature was raised to an internal temperature of 95 ° C., the pressure was reduced to a slight pressure (internal pressure of 92 kPa), and then the reaction was performed while refluxing and dehydrating at an internal temperature of 95 to 122 ° C. for 2 hours. went. Subsequently, the pressure was restored with nitrogen, and the reaction was further performed under reflux at 2.5 to 135 ° C. for 2.5 hours under normal pressure.
After the reaction, toluene was distilled off under normal pressure at an internal temperature of 141 to 142 ° C., and then the pressure was reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. 590 g of condensate was obtained. Table 3 shows the physical properties and the like of the obtained novolak type cocondensate.

<Example 3>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 120.0 g of the cocondensate obtained in Example 2 and stearic acid as a softening agent (bead stearic acid Tsubaki (manufactured by NOF CORPORATION) )) After adding 30.0 g in order, the mixture was stirred at an internal temperature of 140 to 150 ° C. for 1 hour to uniformly mix the cocondensate and stearic acid. Thereafter, the mixture was taken out into a vat and cooled to obtain 149.1 g of a resin composition containing a cocondensate and stearic acid. Table 5 shows the physical properties and the like of the obtained resin composition.

Except for changing the production conditions as shown in Tables 1 and 2, Examples 4 to 6, 8, 11 and 12 are the same as Example 1, and Examples 7 and 10 are the same as Example 3. Similarly, a novolac type cocondensate was obtained. Table 3 shows the physical properties and the like of the obtained novolak type cocondensate.

<Example 9>
120.0 g of the cocondensate obtained in Example 8 and 30.0 g of stearic acid were mixed in the same manner as in Example 3 to obtain 148.8 g of a resin composition containing the cocondensate and stearic acid. It was. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 13>
120.0 g of the cocondensate obtained in Example 12 and 30.0 g of stearic acid were mixed in the same manner as in Example 3 to obtain 147.0 g of a resin composition containing the cocondensate and stearic acid. Obtained. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 14>
In the same manner as in Example 3, 120.0 g of the cocondensate obtained in Example 4 and 30.0 g of industrial cashew nut shell liquid (TAN HOA HOP PHAT Co., Ltd., CNSL) (oil at room temperature) were obtained. By mixing, 149.5 g of a resin composition containing a cocondensate and CNSL was obtained. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 15>
120.0 g of the cocondensate obtained in Example 8 and 30.0 g of CNSL were mixed in the same manner as in Example 3 to obtain 146.6 g of a resin composition containing the cocondensate and CNSL. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 16>
Into a four-necked separable flask equipped with a reflux condenser and a thermometer, 117.4 g (3.60 mol) of paraform having a purity of 92%, 352.5 g (2.35 mol) of p-tert-butylphenol, p-phenylphenol 8 0.5 g (0.05 mol) and 350.0 g of toluene were sequentially added. Thereafter, the temperature was raised to an internal temperature of 40 ° C., 46.0 g (0.55 mol) of a 48% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm was stopped. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 64 ° C. and reacted at the same temperature for 1 hour. When the reaction mixture was analyzed by GPC after the reaction, the molecular weight of the resol-type condensate was Mw = 226 and Mn = 203. Subsequently, it heated up to 88 degreeC of internal temperature and reacted at the same temperature for 6 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 1144 and Mn = 739.
After completion of the reaction, 81.2 g (0.248 mol) of 30% sulfuric acid and 3.47 g (0.028 mol) of oxalic acid dihydrate were added and stirred for 0.2 hours, and the lower aqueous layer was removed. The resol-type condensate in the four-neck separable flask was 778 g (pure content 55%).
Subsequently, 21.2 g (1.92 mol) of resorcin was added, the temperature was raised to an internal temperature of 101 ° C., and the reaction was carried out under reflux and dehydration at an internal temperature of 101 to 120 ° C. for 1.5 hours. Subsequently, the pressure was restored with nitrogen, and the reaction was further performed under reflux at 121-128 ° C. for 1 hour under normal pressure.
After the reaction, toluene was distilled off under normal pressure and at an internal temperature of 142 to 144 ° C., and then the pressure was reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. 611 g of condensate was obtained. Table 3 shows the physical properties and the like of the obtained novolak type cocondensate.

<Example 17>
Resin containing a resin composition containing 400.0 g of the cocondensate obtained in Example 16 and 101.0 g of stearic acid by the same method as in Example 3 and containing the cocondensate and stearic acid 500.2 g of composition was obtained. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 18>
In the same manner as in Example 16 except that 148.8 g of stearic acid (beef stearic acid Tsubaki, manufactured by NOF Corporation) was added at the same time as the conditions shown in Table 2 and resorcin were added,
713 g of a uniform resin composition containing a novolac type cocondensate was obtained. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 19>
A novolak-type co-polymer was prepared in the same manner as in Example 16 except that the production conditions were as shown in Table 2 and that 158.7 g of stearic acid (bead stearic acid Tsubaki made by NOF Corporation) was added at the same time when resorcin was added. 789 g of a uniform resin composition containing the condensate was obtained. Table 5 shows the physical properties and the like of the obtained resin composition.

<Example 20>
The production conditions were as shown in Table 2, and water was distilled from the reaction system by dehydrating with a Dean-Stark tube until the internal temperature was raised to 86 ° C. during the synthesis of the resol-type condensate (46 0.6 g), a novolac-type cocondensate was obtained in the same manner as in Example 16. Table 3 shows the physical properties and the like of the obtained novolak type cocondensate.

<Reference Example 1: Japanese Patent Laid-Open No. 2015-52097 Example 4 Additional Test>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 90.0 g (1.11 mol) of formalin with a purity of 37%, 15.0 g (0.10 mol) of p-tert-butylphenol, 85 of o-phenylphenol 85 0.0 g (0.50 mol) was added in order. Thereafter, the internal temperature was raised to 45 ° C., 20.0 g (0.12 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C. and kept at that temperature for 1.5 hours. Thereafter, the temperature was raised again until the internal temperature reached 75 ° C., and the reaction was terminated by further maintaining the temperature for 3 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 570 and Mn = 400.
After completion of the reaction, the reaction mixture was cooled to an internal temperature of 65 ° C. or lower and diluted with 77.0 g of MIBK. Thereafter, the reaction solution was neutralized, stirred for 10 minutes, and allowed to stand to remove the aqueous layer. The resol-type condensate in the four-neck separable flask was 217 g (64% pure content).
Subsequently, 69.3 g (0.63 mol) of resorcin was added, the temperature was raised to an internal temperature of 100 ° C., the pressure was reduced (internal pressure: 65 kPa), and then the reaction was performed while refluxing and dehydrating at an internal temperature of 100 to 120 ° C. for 4 hours. It was. Subsequently, the pressure was restored with nitrogen, and the reaction was further carried out under reflux and dehydration at 125 ° C. for 8 hours under normal pressure.
After the reaction, the mixture was concentrated at reduced pressure (internal pressure 10 kPa) and at an internal temperature of 140 to 150 ° C. for 2 hours to obtain 183 g of an orange novolak type cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate.

<Reference Example 2: JP 2014-152220 A Example 2 Additional Test>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 43.5 g (1.33 mol) of paraformaldehyde with a purity of 92%, 150.0 g (1.00 mol) of p-tert-butylphenol, 75.0 g of toluene Were added in order. Thereafter, the temperature was raised to an internal temperature of 45 ° C., 4.16 g (0.05 mol) of a 48% aqueous sodium hydroxide solution was added, and the mixture was stirred until the heat generation stopped. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C. and kept at that temperature for 2 hours. Thereafter, the temperature was raised again until the internal temperature reached 80 ° C., and the temperature was further maintained for 1.5 hours. When the reaction mixture was analyzed by GPC after the reaction, the molecular weight of the resol-type condensate was Mw = 297 and Mn = 241.
After completion of the reaction, the mixture was cooled to an internal temperature of 75 ° C. or lower, and 110.0 g (1.00 mol) of resorcin was added without neutralization. The temperature was raised to an internal temperature of 108 to 112 ° C., and azeotropic dehydration was performed over 3 hours. Subsequently, the temperature was raised to an internal temperature of 140 to 150 ° C. with normal pressure, and the toluene was distilled off by keeping the temperature for 2 hours. Thereafter, the pressure was reduced to 21 kPa while maintaining the internal temperature at 140 to 150 ° C., and the toluene was further distilled off by maintaining the temperature for 2 hours.
By the above operation, 280 g of a non-uniform orange novolak type cocondensate was obtained. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Reference Example 3: Japanese Unexamined Patent Publication No. 2007-9047 Comparative Example 3 Additional Test>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 52.2 g (1.60 mol) of paraformaldehyde with a purity of 92%, 150.0 g (1.00 mol) of p-tert-butylphenol, 200.0 g of toluene Were added in order. Thereafter, the internal temperature was raised to 45 ° C., 6.66 g (0.05 mol) of 30% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 70 ° C. and kept at that temperature for 1 hour. When the reaction mixture was analyzed by GPC after the reaction, the molecular weight of the resol-type condensate was Mw = 215 and Mn = 192.
After completion of the reaction, the internal temperature was cooled to 40 ° C., and 9.40 g (0.037 mol) of oxalic acid dihydrate and 132.2 g (1.20 mol) of resorcin were added. The temperature was raised to an internal temperature of 108 to 112 ° C., and azeotropic dehydration was performed. Further, when reflux dehydration was continued at an internal temperature of 110 to 118 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution part, a yellow swollen resin part, Separated. After the reaction for 2 hours as it was, the temperature was successively raised to an internal temperature of 140 ° C. while distilling off toluene, but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Then, toluene was distilled off by keeping the reaction mass in a state where it was not uniformly stirred for 2 hours. Thereafter, the pressure was reduced to 12 kPa while maintaining the internal temperature at 140 to 150 ° C., and the reaction mass was foamed and partially solidified.
By the above operation, 314 g of a non-uniform orange novolac type cocondensate was obtained. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative Example 1>
To a four-necked separable flask equipped with a reflux condenser and a thermometer, 180.0 g (2.22 mol) of formalin having a purity of 37% and 180.0 g (1.20 mol) of p-tert-butylphenol were sequentially added. Thereafter, the internal temperature was raised to 40 ° C., 30.0 g (0.18 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C., and the reaction was carried out at the same temperature for 1 hour and at an internal temperature of 82 ° C. for 3 hours. When the reaction mixture was analyzed by GPC after the reaction, the molecular weight of the resol-type condensate was Mw = 708 and Mn = 450.
After completion of the reaction, 135.0 g of MIBK, 27.0 g (0.083 mol) of 30% sulfuric acid and 1.13 g (0.009 mol) of oxalic acid dihydrate were added, and the mixture was allowed to stand for 0.1 hour, and left to stand. Was removed. The resol-type condensate in the four-neck separable flask was 380 g (pure content 67%).
Subsequently, 158.4 g (1.44 mol) of resorcin was added, the temperature was raised to 96 ° C. and the pressure was reduced to a low pressure (92 kPa), and then the reaction was carried out while refluxing and dehydrating at 110 ° C. to 115 ° C. for 2 hours. . Thereafter, when reflux dehydration was further continued at an internal temperature of 115 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution portion, a yellow swollen resin portion, Separated. Therefore, 135.0 g of MIBK was added to try to dissolve the resin part, but it did not dissolve.
Subsequently, the pressure was restored with nitrogen, and the temperature was raised gradually to an internal temperature of 137 ° C., but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Thereafter, MIBK was distilled off at an internal temperature of 140 to 142 ° C. under normal pressure while the reaction mass was not uniformly stirred, and then further reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. Distillation gave 366 g of a heterogeneous, yellow novolac-type cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative example 2>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 120.0 g of the cocondensate obtained in Comparative Example 1, stearic acid as a softening agent (bead stearic acid Tsubaki (manufactured by NOF CORPORATION) 30.0 g was added in order, and then the temperature was raised to an internal temperature of 145 ° C. and stirred for 1 hour while keeping the internal temperature at 140 to 150 ° C., but a part was separated. When the contents were taken out into the vat and cooled, 147.9 g of a solid (resin composition) in which the cocondensate and stearic acid were heterogeneously mixed was obtained. Table 5 shows the physical properties and the like.

<Comparative Example 3>
To a four-necked separable flask equipped with a reflux condenser and a thermometer, 180.0 g (2.22 mol) of formalin having a purity of 37% and 180.0 g (1.20 mol) of p-tert-butylphenol were sequentially added. Thereafter, the internal temperature was raised to 40 ° C., 160.0 g (0.96 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 55 ° C., and the reaction was carried out at the same temperature for 1 hour. When the reaction mixture was analyzed by GPC, the molecular weight of the resol-type condensate was Mw = 254 and Mn = 237. Next, the temperature was raised to an internal temperature of 65 ° C., and the reaction was carried out at the same temperature for 1.5 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 284 and Mn = 273.
After completion of the reaction, 135.0 g of toluene, 142.0 g (0.435 mol) of 30% sulfuric acid and 6.05 g (0.048 mol) of oxalic acid dihydrate were added, and the mixture was allowed to stand for 0.1 hour and then left to stand. The layer was removed. The resol-type condensate in the four-neck separable flask was 421 g (pure content 68%).
Subsequently, 224.4 g (2.04 mol) of resorcin was added, and the temperature was raised to an internal temperature of 100 ° C. to make a slightly reduced pressure (92 kPa), and then the reaction was performed while refluxing and dehydrating at 100 ° C. to 117 ° C. for 1 hour. . Thereafter, when reflux dehydration was further continued at an internal temperature of 115 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution portion, a yellow swollen resin portion, Separated. Therefore, 135.0 g of toluene was added to try to dissolve the resin part, but it did not dissolve.
Subsequently, the pressure was restored with nitrogen, and the temperature was raised gradually to an internal temperature of 137 ° C., but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Thereafter, toluene is distilled off at an internal temperature of 140 to 142 ° C. under normal pressure while the reaction mass is not uniformly stirred, and then the pressure is reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. Distilling off gave 448 g of a heterogeneous, yellow novolac cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative example 4>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 180.0 g (2.22 mol) of formalin with a purity of 37%, 144.0 g (0.96 mol) of p-tert-butylphenol, o-tert-butylphenol 36.0 g (0.24 mol) was added in order. Thereafter, the internal temperature was raised to 40 ° C., 80.0 g (0.48 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 55 ° C., and the reaction was carried out at the same temperature for 6 hours. When the reaction mixture was analyzed by GPC, the molecular weight of the resol-type condensate was Mw = 310 and Mn = 286.
After completion of the reaction, 135.0 g of MIBK, 72.0 g (0.220 mol) of 30% sulfuric acid and 3.02 g (0.024 mol) of oxalic acid dihydrate were added and stirred for 0.1 hour. Was removed. The resol-type condensate in the four-neck separable flask was 383 g (pure content 65%).
Subsequently, 198.0 g (1.80 mol) of resorcin was added, the temperature was raised to 100 ° C., and the pressure was reduced to a low pressure (92 kPa). went. Thereafter, when reflux dehydration was further continued at an internal temperature of 115 to 120 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution portion and a yellow swollen resin were obtained. It was in a state separated into parts.
Subsequently, the pressure was restored with nitrogen, and the temperature was sequentially raised to an internal temperature of 141 ° C., but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Thereafter, MIBK was distilled off at an internal temperature of 142 to 144 ° C. under normal pressure while the reaction mass was not uniformly stirred, and further reduced by reducing the pressure to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. Distillation gave 406 g of a heterogeneous, yellow novolac cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative Example 5>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 180.0 g (2.22 mol) of formalin having a purity of 37%, 121.5 g (0.81 mol) of p-tert-butylphenol, o-phenylphenol 66 .3 g (0.39 mol) was added in order. Thereafter, the internal temperature was raised to 40 ° C., 60.0 g (0.36 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C. and the reaction was carried out at the same temperature for 3 hours. The molecular weight of the reaction mixture was Mw = 445 and Mn = 371. After completion of the reaction, 135.0 g of toluene, 53.0 g (0.16 mol) of 30% sulfuric acid and 2.40 g (0.019 mol) of oxalic acid dihydrate were added, and the mixture was allowed to stand for 0.1 hour, and left to stand. The layer was removed. The resol-type condensate in the four-neck separable flask was 383 g (pure content 66%).
Subsequently, 171.6 g (1.56 mol) of resorcin was added, the temperature was raised to an internal temperature of 106 ° C. and the pressure was slightly reduced (92 kPa), and then the reaction was conducted while refluxing and dehydrating at 106 ° C. to 119 ° C. for 2 hours. . Thereafter, when reflux dehydration was further continued at an internal temperature of 115 to 120 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution portion and a yellow swollen resin were obtained. It was in a state separated into parts.
Subsequently, the pressure was restored with nitrogen, and the temperature was sequentially raised to an internal temperature of 132 ° C., but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Thereafter, while the reaction mass is not uniformly stirred, toluene is distilled off at normal pressure and at an internal temperature of 132 to 144 ° C., and then the pressure is reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. Distillation gave 330 g of a heterogeneous, yellow novolac cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative Example 6>
A four-necked separable flask equipped with a reflux condenser and a thermometer was charged with 180.0 g (2.22 mol) of formalin having a purity of 37%, 176.4 g (1.18 mol) of p-tert-butylphenol, o-phenylphenol 4 .3 g (0.03 mol) was added in order. Thereafter, the internal temperature was raised to 40 ° C., 80.0 g (0.48 mol) of a 24% aqueous sodium hydroxide solution was added, and the mixture was stirred until the exotherm subsided. After confirming that the exotherm had subsided, the temperature was raised to an internal temperature of 65 ° C. and stirred at the same temperature for 1 hour. When the reaction mixture was analyzed by GPC, the molecular weight of the resol-type condensate was Mw = 251 and Mn = 233. Subsequently, the temperature was raised to an internal temperature of 82 ° C., and the reaction was performed at the same temperature for 2 hours. The molecular weight of the resol-type condensate after the reaction was Mw = 409 and Mn = 355.
After completion of the reaction, 135.0 g of toluene, 72.0 g (0.220 mol) of 30% sulfuric acid, and 3.02 g (0.024 mol) of oxalic acid dihydrate were added, and the mixture was allowed to stand for 0.1 hour, and left to stand. The layer was removed. The resol type condensate in the four-neck separable flask was 399 g (pure content 66%). Subsequently, the reaction mixture after the mixing operation was heated again and kept at an internal temperature of 82 ° C. for 4 hours. The molecular weight of the resol-type condensate after incubation was Mw = 1085 and Mn = 649.
Subsequently, 92.4 g (0.84 mol) of resorcin was added, the temperature was raised to an internal temperature of 106 ° C., and the pressure was slightly reduced (92 kPa), and then the reaction was performed while refluxing and dehydrating at 106 to 113 ° C. for 2 hours. . Thereafter, when reflux dehydration was further continued at an internal temperature of 115 ° C., the viscosity of the reaction mass began to increase, and after 0.5 hours, the reaction mass swelled, and a colorless and transparent solution portion, a yellow swollen resin portion, Separated.
Subsequently, the pressure was restored with nitrogen, and the temperature was sequentially raised to an internal temperature of 132 ° C., but there was no change in the state of the separated reaction mass. Further, since the reaction mass was separated, only the periphery of the stirring shaft rotated, and uniform stirring could not be performed.
Thereafter, toluene is distilled off at an internal temperature of 140 to 142 ° C. under normal pressure while the reaction mass is not uniformly stirred, and then the pressure is reduced to 16 kPa while maintaining the internal temperature of 140 to 150 ° C. Distillation gave 343 g of a heterogeneous, yellow novolac cocondensate. Table 4 shows the physical properties and the like of the obtained novolak type cocondensate (sampled as uniform as possible).

<Comparative Example 7>
In a four-necked separable flask equipped with a reflux condenser and a thermometer, 120.0 g of the cocondensate obtained in Reference Example 1 and stearic acid (bead stearic acid Tsubaki (manufactured by NOF CORPORATION) 30.0 g was added in order, and then the temperature was raised to an internal temperature of 145 ° C. and stirred for 1 hour while keeping the internal temperature at 140 to 150 ° C., but a part was separated. When the contents were taken out into the vat and cooled, 149.3 g of a solid (resin composition) in which the cocondensate and stearic acid were mixed inhomogeneously were obtained. Table 5 shows the physical properties and the like.

Tables 1 and 2 show the detailed conditions of each of the above examples, Tables 3 and 4 show the physical properties of the cocondensates obtained in each of the examples, and Table 5 shows a resin composition obtained in each of the examples. The physical properties of

In each table, the content of each component is a value based on weight (% by weight) excluding each oligomer component, and the oligomer component is an area percentage value. The structural unit derived from PTBP is a structural unit derived from p-tert-butylphenol (mol%) relative to the structural unit derived from all phenols (excluding resorcin), and the structural unit derived from resorcin is all phenols (excluding resorcin) It is a resorcin-derived structural unit (mol%) with respect to the derived structural unit.

The meanings of the abbreviations in the following tables are as follows.
RES: Resorcin PTBP: p-tert-butylphenol OPP: o-phenylphenol OTBP: o-tert-butylphenol PPP: p-phenylphenol MIBK: methyl isobutyl ketone oligomer 1: peak top molecular weight in gel permeation chromatography (GPC) method Is the content of components having a peak top molecular weight of 430 to 320 in the gel permeation chromatography (GPC) method. Peak top is the peak of the peak detected as the oligomer component contained in each cocondensate Top value (molecular weight).

The evaluation criteria of the reaction mass properties in Tables 1 and 2 are as follows.
Reaction mass properties ・ Reaction mass did not swell and separated in step (3), and stirring could be continued: Good ・ Reaction mass swelled and separated in step (3), and stirring was difficult / impossible : Defect

The evaluation criteria of the compatibility between the cocondensate and the softener in Table 5 (“resin compatibility” in Table 5) are as follows.
A uniform resin composition having good compatibility between the cocondensate and the softener and being solid at room temperature (25 ° C.) was obtained. The resin composition has no turbidity or white turbidity: Good The compatibility of the cocondensate and the softening agent was poor, and a solid and uniform resin composition could not be obtained at room temperature (25 ° C). The resin composition is opaque, and turbidity and white turbidity are present sparsely: Poor

2. Evaluation of Hygroscopicity / Blocking Property and Odor of Cocondensate and Resin Composition (1) Evaluation of Hygroscopicity / Blocking Property The cocondensate produced in Example 16, Reference Example 1 and Reference Example 2, and Example 3 and Put the resin composition manufactured in Example 19 and the commercially available resin adhesive SUMIKANOL620 (Taoka Chemical Industries, Ltd., hereinafter also referred to as SKL620) on a PE cap (dish), Place each cap on an aluminum tray and place it in a constant temperature and humidity chamber of 40 ° C. and 90% RH. After the time shown in Table 6 below, the weight increase rate and appearance of each sample are based on the following criteria. And evaluated. Table 6 shows the results.
◯: The cocondensate or resin composition particles did not adhere to each other, and the initial appearance was maintained.
(Triangle | delta): The mutual adhesion of the grain of a cocondensate or a resin composition generate | occur | produced partially, and the lump existed in part.
X: The cocondensate or the resin composition particles were adhered to each other and integrated.
XX: Cocondensate or resin composition grains were adhered to each other and melted, and the boundary disappeared.

As shown in Table 6 above, the commercially available SKL620 and the cocondensate obtained in Reference Example 1 and Reference Example 2 produced by a known method are hygroscopic and have low blocking resistance, while the present invention. It was found that the cocondensate and the resin composition produced by the above method have low hygroscopicity and excellent blocking resistance.

(2) Odor Evaluation The cocondensate produced in Examples 6 and 16, the resin composition produced in Examples 3 and 19, and SKL620 were pulverized and placed in a 15 g polystyrene bottle as a test sample. Six testers smelled the obtained test sample with its contents turned down, and the odor was determined. The odor was evaluated according to the following criteria. Table 7 shows the evaluation results. In addition, Table 7 shows the presence or absence of brown coloration of the cocondensate or resin composition and the spectral transmittance at a wavelength of 610 nm.
Odor intensity: 0 (no odor) to 5 (strong odor)
Pleasure level: +4 (Pleasure) to -4 (Pleasure)
Improvement level: Improvement rate of average value based on SKL620

As shown in Table 7 above, it was found that the cocondensate and the resin composition of the present invention had an improved odor compared to the commercially available SKL620. In particular, it has been found that the odor of the cocondensate and the resin composition having a spectral transmittance (wavelength of 610 nm) of 80% or more is greatly improved.

3. Production Examples and Physical Properties Evaluation of Rubber Compositions Using the Cocondensates and Resin Compositions Obtained in the above Examples (1) Unvulcanized rubber compositions containing the cocondensates and resin compositions obtained in the above Examples Manufacture of a thing As a resin adhesive, the cocondensate manufactured in Example 6 and Example 11 and the resin composition manufactured in Example 3, Example 9, Example 14, Example 15, and Example 19 are included. An unvulcanized rubber composition was produced by the following method. In addition, an unvulcanized rubber composition containing the co-condensate obtained in SKL620 and Reference Example 1 and an unvulcanized rubber composition containing no resin adhesive were produced by the following methods.

<Method for producing unvulcanized rubber composition>
According to the formulation shown in Table 8, first, components other than insoluble sulfur, a vulcanization accelerator and a methylene donor, and a resin adhesive were added and mixed with a pressure kneader made by Toshin, and discharged when the temperature reached 160 ° C. Next, an unvulcanized rubber composition was produced by adding and mixing insoluble sulfur, a vulcanization accelerator and a methylene donor to the obtained mixture with a 6-inch open roll manufactured by Kansai Roll Co., Ltd. which was kept at 60 ° C.
In addition, the numerical value in Table 8 represents a weight part. The details of each component in Table 8 are as follows.

・ Natural rubber: SMR-CV60
・ Carbon black: "Seast 300" (HAF-LS grade) manufactured by Tokai Carbon Co., Ltd.
・ Zinc flower: Zohua Chemical Industry Co., Ltd. 2 types of zinc flower ・ Aging inhibitor: “Antioxidant FR” manufactured by Matsubara Sangyo Co., Ltd.
・ Cobalt salt: Cobalt stearate (reagent)
Insoluble sulfur: “Cristex HS OT-20” manufactured by Flexis
・ Vulcanization accelerator: N, N-dicyclohexyl-2-benzothiazolylsulfenamide (reagent)
・ Methylene donor: “Sumikanol 507AP” manufactured by Bara Chemical Co., Ltd.

(2) Physical property test of unvulcanized rubber composition and physical property test of vulcanized rubber composition Using the unvulcanized rubber composition obtained as described above, Mooney viscosity test (conforming to JIS K 6300-1: 2001, 130 ° C) And rheometer test (according to JIS K 6300-2: 2001, measured at 160 ° C.).

Further, after preparing an unvulcanized sample, it was allowed to stand at room temperature for 24 hours, and then vulcanized under conditions of t90 + 5 minutes under a pressure of 160 ° C. and 6 MPa to prepare a vulcanized rubber sheet having a thickness of 2 mm. Then, using a rubber test piece prepared from the vulcanized rubber sheet, a tensile test (measured at 25 ° C. according to JIS K 6251: 2010), a measurement of hardness (measured at 25 ° C. according to JIS K 6253: 2006), and Measurement of viscoelasticity was performed. Viscoelasticity was measured under the following conditions.
Viscoelastic device DSI6100 manufactured by SII Nano Technology Co., Ltd.
Conditions: Temperature 40 ° C. to 80 ° C. (Temperature increase rate: 2 ° C./min) Dynamic strain 0.2%, frequency 10 Hz
Test piece: long side 50 mm × short side 5 mm × thickness 2 mm

Table 9 shows the respective physical property values (relative values) when the physical property values of the rubber composition not added with the resin adhesive (Comparative Example 8) are set to 100 with respect to the rubber physical property test results described above.

As shown in Table 9 above, the rubber composition containing the cocondensate of the present invention and the resin composition was confirmed to have improved physical properties as compared with the rubber composition not added with the resin adhesive (Comparative Example 8). It was proved that the rubber composition containing the resin adhesive “SUMIKANOL620” and the cocondensate obtained in Reference Example 1 showed performance equal to or higher than that of the rubber composition.

(3) Initial Adhesiveness and Wet Heat Adhesiveness of Vulcanized Rubber Composition A sample of a rubber-steel cord composite was prepared using each of the unvulcanized rubber compositions obtained as described above. Specifically, brass-plated steel cord (diameter of about 0.8 mm, 3 × 0.20 + 6 × 0.35 mm structure, brass plating of copper / zinc = 64/36 (weight ratio)) at intervals of 1/10 mm For the peel adhesion test, both sides of the array of five were coated with about 2 mm thick unvulcanized rubber sheets made of each of the above unvulcanized rubber compositions, and the cords were laminated in parallel. An unvulcanized sample was prepared. Using the obtained unvulcanized sample, initial adhesiveness and wet heat adhesiveness were evaluated by the following methods.

<Initial adhesiveness>
The above-mentioned unvulcanized sample was prepared and allowed to stand at room temperature for 24 hours, and then vulcanized under conditions of t90 + 5 minutes under pressure at 160 ° C. and 6 MPa, and 1 cm × 1 cm × 6 cm with 5 steel cords sandwiched by 1 cm. A rectangular rubber piece was obtained. This rubber piece is subjected to a steel cord pull-out test using an autograph “AGC-X” manufactured by Shimadzu Corporation, and the stress at the time of pulling out vertically at 100 mm / min is the rubber pulling stress (kgf ). Further, the rubber coverage of the steel cord after drawing was visually observed and evaluated from 0 to 100%. Measurement and evaluation were carried out at N = 10 (pieces), and an average value was obtained. The results are shown in Table 10.

<Wet heat adhesion (adhesion after wet heat aging)>
The unvulcanized sample was prepared, and a rubber piece vulcanized in the same procedure as the initial adhesion evaluation was used as a test piece. The test piece was placed in steam at 80 ° C. × 95% RH for 7 days, 14 days, and 21 days. After leaving, a pull-out test similar to the above initial adhesiveness was performed, and the rubber coverage of the steel cord after pulling was visually observed and evaluated at 0 to 100%. Measurement and evaluation were carried out at N = 10 (pieces), and an average value was obtained. The results are shown in Table 10. The pulling strength change rate in Table 10 is the change rate when the initial value (0 day, before wet heat aging) is taken as 100 (tensile strength after wet heat aging / tensile strength before wet heat aging × 100). It is.

As shown in Table 10 above, the rubber composition containing the cocondensate of the present invention and the resin composition has a rubber-steel cord adhesive strength as compared with the rubber composition to which no resin adhesive is added (Comparative Example 8). It was found that the performance was greatly improved and the performance was equal to or better than the rubber composition containing the known resin adhesive “SUMIKANOL620” and the cocondensate obtained in Reference Example 1.

Claims (12)

A method for producing a novolac-type cocondensate,
The novolac-type cocondensate has the following general formula (i):

(R represents an optionally substituted alkyl group having 1 to 12 carbon atoms or a phenyl group.)
Including one or more phenols represented by the formula, formaldehyde and resorcin-derived structural units,
The structural unit derived from phenols contains 65 mol% or more of a structural unit derived from p-tert-butylphenol,
The manufacturing method includes the following steps (1), (2) and (3) in this order.
(1) A resole having a number average molecular weight of 600 or more in gel permeation chromatography by reacting the phenols with formaldehyde at 75 ° C. or more in the presence of 0.05 mol or more of base with respect to 1 mol of the phenols. A step of obtaining a mold condensate.
(2) A step of mixing the reaction liquid containing the resol-type condensate obtained in the step (1) with an acid of an equivalent amount or more with respect to the base used in the step (1).
(3) A step of reacting the resole type condensate with 0.5 to 1.2 moles of resorcin to 1 mole of the phenols. The method for producing a novolak type cocondensate according to claim 1, wherein the amount of resorcin used is 0.5 to 0.8 mol per mol of the phenols. The method for producing a novolak type cocondensate according to claim 1 or 2, wherein the amount of the base used in the step (1) is 0.05 to 0.25 mol with respect to 1 mol of the phenol. A novolak type cocondensate satisfying all of the following (a) to (e).
(A) The following general formula (i):

(R represents an optionally substituted alkyl group having 1 to 12 carbon atoms or a phenyl group.)
The structural unit derived from 1 type, or 2 or more types of phenols represented by these, formaldehyde, and resorcinol is included.
(B) The phenol-derived structural unit contains 65 mol% or more of a structural unit derived from p-tert-butylphenol.
(C) The number average molecular weight in the gel permeation chromatography method is 750 or more.
(D) Softening point is 80 to 150 ° C.
(E) The structural unit derived from resorcin is 0.80 mol or less with respect to 1 mol of the structural unit derived from the phenols. The novolak-type cocondensate according to claim 4, further satisfying the following (f):
(F) In the gel permeation chromatography method, the component having a peak top molecular weight of 700 to 520 is contained in an area percentage of 1 to 10%, and the component having a peak top molecular weight of 430 to 320 is contained in an area percentage of 0.01 to 2%. The novolak-type cocondensate according to claim 4 or 5, wherein the spectral transmittance at a wavelength of 610 nm of a solution obtained by dissolving 2.0 g of the novolak-type cocondensate in 20 mL of tetrahydrofuran is 80% or more. A resin composition comprising the novolak type cocondensate according to any one of claims 4 to 6 and a softening agent. The resin composition according to claim 7, wherein the softening agent is a fatty acid having 8 to 32 carbon atoms. The resin composition according to claim 7, wherein the softening agent is a cashew nut shell liquid. The resin composition according to any one of claims 7 to 9, wherein the content of the softening agent in the resin composition is 5 to 40% by weight. The resin composition according to any one of claims 7 to 10, wherein the spectral transmittance at a wavelength of 610 nm of a solution obtained by dissolving 2.0 g of the resin composition in 20 mL of tetrahydrofuran is 80% or more. A rubber composition comprising the novolak-type cocondensate according to any one of claims 4 to 6 or the resin composition according to any one of claims 7 to 11 and a rubber component.