WO2017002885A1 - Surface layer-peelable composite coating film, coating composition for forming composite coating film, and method - Google Patents

Abstract

The present invention provides an oxidative polymerization resin-based composite coating film, the coating film surface layer of which can be updated a plurality of times by peeling off a surface layer. More specifically, the present invention forms a composite coating film comprising a cured skin layer and an uncured inner layer using: a base resin composition including an oxidative polymerization resin; an organic compound having a melting point of 5-150°C; a dryer; and a coating composition including an oxidative polymerization inhibitor including at least one of a dryer protective agent and a radical inhibitor.

Description

Composite coating film capable of peeling off surface layer, coating composition and method for forming composite coating film

The present invention provides a surface-peelable composite coating, a coating composition for forming such a composite coating, and a method thereof.

An alkyd resin is an oxidative polymerizable resin synthesized from a polybasic acid or polybasic acid anhydride, a polyhydric alcohol, and a fatty acid. The oxidative polymerizable resin undergoes ester oxidative polymerization with oxygen in the air at room temperature. Thus, a three-dimensional network structure is formed, and a coating film having excellent solvent resistance and water resistance is obtained. Alkyd resin-based paints can be used for various materials, and because they are inexpensive, they are useful for a wide range of applications from indoor wall painting to painting of large structures such as buildings, ships, and vehicles. .

As a paint containing an alkyd resin, Patent Document 1 discloses a resin composition and a coating material that are useful as civil engineering and building materials that retain low-temperature flexibility and are excellent in low-temperature curability, and that are radically cured. This resin composition contains (A) a polyether acrylic urethane resin, (B) an air-drying imparting polymer using a drying oil and / or a fatty acid compound thereof, and (C) an ethylenically unsaturated monomer. To do. The component (B) is preferably an alkyd resin. In the resin composition, in addition to the components (A) to (C), paraffin and / or wax (D) may be used in combination for the purpose of improving the drying property.

Patent Document 2 discloses a resin composition and a covering material that are suitable for a wide range of civil engineering and building material applications and are radically cured, as in Patent Document 1. This resin composition comprises (A) a resin having a (meth) acryloyl group at the molecular end, (B) an air-drying imparting polymer using a drying oil and / or a fatty acid compound thereof, and (C) a molecular weight of 160 or more. The ethylenically unsaturated monomer which has the (meth) acryloyl group of this is contained. The component (B) is preferably an alkyd resin. In the resin composition, in addition to the components (A) to (C), paraffin and / or wax (D) may be used in combination for the purpose of improving the drying property.

Patent document 3 discloses a coating composition having a thermosetting film-forming property and based on a wax or a wax-like compound (for example, polyethylene wax, paraffin wax, etc.) or a natural drying oil or an alkyd resin. This coating composition is used to prevent corrosion of the metal substrate of the car body and is an additive that gels at relatively high temperatures (eg, C _1-8 alkyl esters of polyvinyl chloride, methacrylic acid or acrylic acid) Etc.) can be completely prevented from flowing or dripping.

JP-A-8-259543 JP-A-8-283357 JP-T-8-503987

If the surface of the paint film is scratched or dirty, or if the function imparted to the paint film is deactivated, it is necessary to repaint. It is difficult to repaint frequently in areas that need to be repainted, such as hospital rooms and precision equipment rooms that must always be kept clean, windbreaks on roads that are easily damaged or contaminated, humid places, and factories.

Since the conventional general coating film is designed to be completely cured, if the coating film surface is damaged, contaminated, or deactivated, difficult re-painting is essential.

Therefore, the development of a coating composition that can form a coating film that can be renewed many times by peeling the surface layer of the coating film, such as a highly versatile alkyd resin coating composition, has been a problem.

As a result of intensive studies to solve the above problems, the present inventors have used a specific coating composition containing a flow suppression and polymerization reaction inhibitor, a dryer and an oxidation polymerization inhibitor in the oxidation polymerizable resin. It has been found that a composite coating film comprising a cured film layer and an uncured inner layer can be formed. The film layer of the composite coating film can be peeled off, and the surface of the uncured inner layer that appears by peeling is exposed to oxygen, and the surface layer is dried and cured to form a new film layer.

The present invention includes a base resin composition comprising an oxidatively polymerizable resin; an organic compound having a melting point of 5 to 150 ° C .; a dryer; and an oxidative polymerization inhibitor comprising at least one of a dryer protective agent and a radical inhibitor. A coating composition is provided.

The present invention is a composite coating film comprising a coating layer and an inner layer,
The inner layer is an uncured body of the coating composition of the present invention, and the coating layer is a cured body of the coating composition formed so as to be peelable on the surface of the inner layer,
Provided is a composite coating film in which a surface layer of an inner layer exposed to air by peeling of the coating layer formed on the inner layer is cured by oxidative polymerization so that another coating layer can be peeled off.

Further, the present invention is a method for producing a composite coating film comprising a coating layer and an inner layer, wherein the coating layer is detachably formed on the surface of the inner layer,
Applying the coating composition of the present invention on a substrate to form a coating film made of an uncured body of the coating composition; and exposing the coating film made of the uncured body to the surface thereof by air exposure A method for producing a composite coating film comprising the steps of: curing by oxidative polymerization to form the coating layer, and maintaining the portion under the coating layer in an uncured state to form an inner layer.

The composite coating according to the present invention can be formed by applying the coating composition of the present invention on a substrate and exposing it to oxygen in the air, when the surface is damaged or contaminated, or applied When the performed function is deactivated, the surface layer can be updated once or a plurality of times by peeling only the coating layer.

Furthermore, the composite coating film according to the present invention can be used as a lower layer, and a top coating can be applied thereon, or an upper material can be formed by applying interior materials such as exterior materials and wallpaper materials. The upper layer can be easily updated by peeling.

Schematic which shows peeling of the composite coating film of this invention, and its film layer. Schematic which shows the formation process of the composite coating film of this invention. Schematic for demonstrating the measuring method of a resilience elastic modulus. Schematic for demonstrating a peeling test.

Hereinafter, the present invention will be described in detail on the basis of preferred embodiments thereof.

1. Coating Composition The coating composition of the present invention comprises at least one of a base resin composition containing an oxidation polymerizable resin; an organic compound having a melting point of 5 to 150 ° C .; a dryer; and a dryer protective agent and a radical inhibitor. In one embodiment, the organic compound is contained in an amount of 10 to 100% by weight with respect to 100% by weight of the base resin composition and 100% by weight of the solid content of the oxidative polymerizable resin. Including an effective amount of the dryer with a metal element content of 0.001 to 1.5% by weight,
When the oxidative polymerization inhibitor includes any one of a dryer protective agent and a radical inhibitor,
Containing from 0.5 to 4 moles of the dryer protective agent per mole of metal elements in the dryer; or
Containing 0.01 to 2.0% by weight of the radical inhibitor with respect to 100% by weight of the oxidative polymerizable resin solid content; or
When the oxidative polymerization inhibitor includes both a dryer protective agent and a radical inhibitor,
When the dryer protective agent is contained in an amount of 0.5 to 4 moles per mole of the metal element in the dryer, the radical inhibitor is contained in an amount of 2.0% by weight or less based on 100% by weight of the oxidative polymerizable resin solid content. Or
When the dryer protective agent is contained in an amount of less than 0.5 mol with respect to 1 mol of the metal element in the dryer, the radical inhibitor is added in an amount of 0.01 to 2.0 wt. % Is included.

In the present invention, the base resin composition is a resin composition containing at least an oxidation polymerizable resin, and may further contain an oxidation polymerizable compound and a coating resin not having an oxidation polymerizable group.

In the present invention, the oxidatively polymerizable resin contained in the base resin composition is a resin containing an oxidatively polymerizable group that undergoes an oxidative polymerization reaction through a reaction with oxygen in the air and three-dimensionally crosslinks, and is not limited. However, alkyd resin which is a reaction product of polybasic acid or polybasic acid anhydride, fatty acid and polyhydric alcohol, reaction product of acrylic resin or urethane resin and fatty acid, and the like can be mentioned.

Examples of the polybasic acid or polybasic acid anhydride in the alkyd resin that can be used in the present invention include, but are not limited to, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, itaconic acid, maleic acid Dicarboxylic acids such as fumaric acid, phthalic acid, isophthalic acid and terephthalic acid; tricarboxylic acids such as trimellitic acid; and compounds having two or more carboxyl groups in the molecule such as tetracarboxylic acid such as pyromellitic acid and their An acid anhydride is mentioned.

The fatty acid in the alkyd resin that can be used in the present invention is not limited, and for example, an iodine value of 130 selected from the group consisting of linseed oil, tung oil, poppy oil, perilla oil, sesame oil, sunflower oil and safflower oil. Fatty acids contained in the above dry oils; fatty acids contained in semi-dry oils having an iodine value of 100 to 130 selected from the group consisting of soybean oil, rice bran oil, cottonseed oil, sesame oil; olive oil, almond oil, peanut oil, coconut oil , Fatty acids contained in non-drying oils having an iodine value of less than 100, selected from the group consisting of coconut oil, rapeseed oil and castor oil. Examples of such fatty acids include, but are not limited to, unsaturated fatty acids such as palmitoleic acid, oleic acid, linoleic acid, and linolenic acid.

Examples of the polyhydric alcohol in the alkyd resin that can be used in the present invention include, but are not limited to, ethylene glycol, diethylene glycol, propylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2-diethyl-1,3-propanediol, neopentyl Diols selected from the group consisting of glycols; and trivalent or higher valent polyols selected from the group consisting of triethylene glycol, trimethylolpropane, trimethylolethane, glycerin, pentaerythritol, and 2,2-dimethylolpropion Acid, 2, - dimethylol butanoic acid, 2,2-dimethylol pentanoic acid, 2,2-dimethylol-hexanoic acid, such as hydroxycarboxylic acids selected from the group consisting of 2,2-dimethylol octanoic acid.

The fatty acid in the reaction product of an acrylic resin or urethane resin and a fatty acid that can be used in the present invention is the same as the fatty acid in the alkyd resin that can be used in the present invention.

The solid content of the oxidatively polymerizable resin is 70 to 100% by weight, preferably 85 to 100% by weight, more preferably 95 to 100% by weight, based on the solid content of the entire base resin composition. If content of the said oxidation polymerizable resin exists in the said range, the dryness of a coating film is ensured.

In the present invention, the oxidatively polymerizable compound that may be contained in the base resin composition is a compound containing an oxidatively polymerizable group that undergoes oxidative polymerization reaction through three-dimensional crosslinking by reaction with oxygen in the air. A fatty acid contained in a dry oil having an iodine value of 130 or more selected from the group consisting of, for example, flaxseed oil, tung oil, poppy oil, perilla oil, egoma oil, sunflower oil and safflower oil; Examples include fatty acids contained in semi-drying oils having an iodine value of 100 to 130 selected from the group consisting of rice bran oil, cottonseed oil, and sesame oil. Examples of such fatty acids include, but are not limited to, unsaturated fatty acids such as palmitoleic acid, oleic acid, linoleic acid, and linolenic acid.

In the present invention, the coating resin that does not have an oxidizable polymerizable group that may be contained in the base resin composition is a general coating resin including an acrylic resin, a urethane resin, an epoxy resin, a polyester resin, and the like. .

In the present invention, an organic compound having a melting point of 5 to 150 ° C. can be kneaded with the base resin composition at a temperature equal to or higher than the melting point, and the resulting mixture is fluidized at the use environment temperature of the coating film. It is a compound which forms a coating film structure without doing. That is, the inner layer, which is an uncured body of the composite coating film, can form and maintain a coating film structure without flowing in the use environment by the action of the organic compound. Moreover, by interposing between each component of oxidatively polymerizable resin, it has the function to prevent the dry hardening reaction by an oxidative polymerization reaction by interfering with the proximity of the oxidatively polymerizable resins. Therefore, in the present invention, the organic compound can be said to be a substance for suppressing flow and polymerization reaction.
In the present invention, when the melting point of the organic compound is 5 ° C. or higher, a coating film structure can be formed in a normal use environment or the like. If the melting point is 150 ° C. or lower, it is not necessary to heat excessively when kneading with the base resin composition.

Examples of the organic compound that can be used in the present invention include, but are not limited to, liquid paraffin, paraffin wax, microcrystalline wax, polyethylene, polyacrylamide, polyacrylate, animal wax, vegetable wax, higher fatty acid, higher alcohol. , Amines, ketones, esters and the like. These organic compounds can be used alone or in admixture of two or more. Paraffins are alkanes represented by C _n H _{2n + 2} , and include liquids and solids at room temperature depending on the carbon number or molecular weight. The liquid one is called liquid paraffin, and the solid one is called paraffin wax. Paraffin wax is generally classified by its melting point rather than carbon number or molecular weight. Paraffin wax includes, for example, those having a low melting point (about 42 ° C.) to a high melting point (about 70 ° C.) and those having a higher melting point. In the present invention, paraffin wax, polyethylene or a combination thereof is preferred.

The content of the organic compound is preferably 10 to 100% by weight with respect to 100% by weight of the base resin composition. When the content is less than the lower limit, it is weak against temperature changes in the use environment, and when it is more than the upper limit, it takes time to form the coating layer. In order to improve the workability of peeling and to secure the number of peeling, the content is more preferably 15 to 50% by weight, and further preferably 20 to 40% by weight.

In the present invention, a dryer is a compound that accelerates the oxidative polymerization of an oxidative polymerizable resin such as an alkyd resin, and mainly generates peroxide by hydrogen abstraction of α-methylene groups of double bonds in the presence of oxygen, It promotes the generation of oxygen radicals by decomposition of the generated peroxide. Polymerization proceeds by radical chain reaction to form a coating film having a three-dimensional network structure.

The dryer that can be used in the present invention includes a metal soap composed of a bond of a metal and a long-chain fatty acid. The metal that can be used for the metal soap is not limited, but examples include metals such as cobalt, barium, vanadium, manganese, cerium, lead, iron, calcium, zinc, zirconium, nickel, tin, and strontium, preferably Cobalt and manganese excellent in surface drying properties, and more preferably cobalt. The long chain fatty acid that can be used for the metal soap is not limited, and examples thereof include organic acids such as propionic acid, octylic acid, naphthenic acid, neodecanoic acid, tung oil acid, linseed oil acid, soybean oil acid, and resin acid. Propionic acid, naphthenic acid and octylic acid are preferred, and naphthenic acid and octylic acid are more preferred. The metal soap that can be used in the present invention is preferably a cobalt salt of naphthenic acid or octylic acid, and more preferably a cobalt salt of naphthenic acid.

The content of the dryer is preferably such that the content of the metal element in the dryer is 0.001 to 1.5% by weight based on 100% by weight of the solid content of the oxidative polymerizable resin. When the content is less than the lower limit, it takes time to form the coating layer. When the content is more than the upper limit, poor appearance such as itchiness tends to occur in the coating layer. In order to improve the workability of peeling and to ensure the number of peeling, the content is more preferably 0.01 to 1.0% by weight, and still more preferably 0.05 to 0.5% by weight.

In the present invention, the oxidative polymerization inhibitor is an agent in which the oxidative polymerizable resin and the oxidative polymerizable compound contained in the base resin composition suppress an oxidative polymerization reaction due to a reaction with oxygen in the air, and a dryer protective agent. And radical inhibitors. The dryer protective agent and the radical inhibitor can be used alone or in combination.

In the present invention, the dryer protective agent is a substance that inhibits the oxidative polymerization promoting effect of the dryer by coexistence with the dryer. Since the volatile dryer protective agent is used in the coating composition of the present invention, the dryer protective agent disappears due to volatilization near the surface of the coating film, and the effect of promoting the oxidative polymerization of the dryer is exhibited. Thereby, only the surface layer of the coating film is cured to form the coating layer. Since this coating layer suppresses volatilization of the internal dryer protective agent and inhibits the oxidative polymerization promoting effect of the dryer, the internal layer is maintained in an uncured state.

The dryer protective agent that can be used in the present invention is a volatile substance having a boiling point of 300 ° C. or lower, and is not limited to, for example, methyl ethyl ketoxime, acetone oxime, butyl aldoxime, cyclohexanone oxime, dialkylhydroxylamine, ammonia, Examples include hydroxylamine, triethylamine, dimethylethanolamine and the like. Methyl ethyl ketoxime and cyclohexanone oxime are preferred.

The content of the dryer protective agent is preferably 0.5 to 4 mol with respect to 1 mol of the metal element in the dryer. When the content is less than the lower limit, the coating layer becomes thick, and when it is more than the upper limit, it takes time to form the coating layer. In order to improve the workability of peeling and to secure the number of peeling, the amount is more preferably 1 to 3 mol, and further preferably 1.5 to 2.5 mol. When using several dryer protection agents together, the total amount should just be in the said range.

In the present invention, the radical inhibitor is not a substance that inhibits the oxidative polymerization promotion of the dryer, but a substance that directly suppresses the oxidative polymerization initiation function of radicals existing in the system, unlike the dryer protective agent. Since the volatile radical inhibitor is used in the coating composition of the present invention, the radical inhibitor disappears due to volatilization near the surface of the coating film, and the radical oxidative polymerization initiation function is exhibited. Thereby, only the surface layer of the coating film is cured to form the coating layer. Since this coating layer suppresses volatilization of the internal radical inhibitor and inhibits the radical oxidative polymerization initiation function, the internal layer is maintained in an uncured state.

The radical inhibitor that can be used in the present invention is a volatile substance having a boiling point of 300 ° C. or less, and includes, but is not limited to, phenolic substances such as eugenol, butylated hydroxytoluene, butylated hydroxyanisole; Examples thereof include phosphite substances such as trimethyl phosphite, triethyl phosphite, and tributyl phosphite. Eugenol and tributyl phosphite are preferred.

The content of the radical inhibitor is preferably 0.01 to 2.0% by weight with respect to 100% by weight of the oxidative polymerizable resin solid content. When the content is less than the lower limit, the coating layer becomes thick, and when it is more than the upper limit, it takes time to form the coating layer. In order to improve the workability of peeling and to ensure the number of peeling, it is more preferably 0.03 to 1.0% by weight, still more preferably 0.05 to 0.5% by weight. When a plurality of radical inhibitors are used in combination, the total amount may be within the above range.

When the dryer protective agent and the radical inhibitor are used in combination, the dryer protective agent is in a range of 4 mol or less with respect to 1 mol of the metal element in the dryer, and the radical inhibitor is 100% by weight of the oxidative polymerizable resin solid content. It can be contained in the range of 2.0% by weight or less. However, the dryer protective agent is in a range of less than 0.5 mol with respect to 1 mol of the metal element in the dryer, and the radical inhibitor is less than 0.01 wt% with respect to 100 wt% of the oxidative polymerizable resin solid content. In this range, the effect of inhibiting oxidative polymerization cannot be sufficiently exerted, and is excluded.

The coating composition of the present invention has the composition described above, and is applied onto a substrate to form a coating film composed of an uncured body of the coating composition. It can be cured by oxidative polymerization to form a composite coating film comprising a cured coating layer and an uncured inner layer under the coating layer. Moreover, since the inner layer of the obtained composite coating film is maintained in an uncured state, the coating layer can be peeled off, and the surface layer of the inner layer exposed to air by the peeling of the coating layer is cured by oxidative polymerization. Then, another film layer is newly formed. As long as there is an uncured inner layer, the surface layer of the coating film can be renewed by peeling the coating layer many times.

In addition to the above essential components, a pigment component can usually be added to the coating composition of the present invention. Examples of pigment components that can be used in the present invention include, but are not limited to, for example, colored pigments such as titanium dioxide, carbon black, petal, phthalocyanine blue, extender pigments such as calcium carbonate, talc, mica, and clay, and further anti-rust pigments. Etc. The content of the pigment component in the coating is preferably 0.1 to 70%, more preferably 0.1 to 50% in terms of pigment weight concentration (PWC) based on the solid content of the coating composition. If the PWC is too low, the coating film may not be sufficiently concealed. If the PWC is too high, it may be difficult to form a coating layer.

The coating composition of the present invention may further contain a commonly used coating additive. Examples of paint additives that can be used in the paint composition of the present invention include, but are not limited to, ultraviolet absorbers, light stabilizers, viscosity modifiers, surface modifiers, antioxidants, fungicides, and algae inhibitors. , Plasticizers, antifoaming agents and the like. The coating additive is usually used in an amount of 0.01 to 10% by weight based on 100% by weight of the coating composition.
The coating composition of the present invention can also contain an organic solvent as long as the effects of the present invention are not affected.

2. Composite Coating The composite coating of the present invention is a composite coating consisting of a coating layer 3 and an inner layer 2 formed using the coating composition of the present invention as shown in FIG. The coating layer 3 formed in the above can be peeled off. The surface layer of the inner layer 2 that has appeared due to the peeling of the coating layer 3 is exposed to air and cured by oxidative polymerization to form a new coating layer 3 separately.
As a coating method, any appropriate method can be adopted depending on the type of the substrate. Although it does not specifically limit, Application | coating by a brush, a trowel, a roller, an air spray, an airless spray etc. is mentioned, for example.
In the composite coating film of the present invention, the inner layer 2 is an uncured body of the coating composition of the present invention, and the coating layer 3 is formed on the surface of the inner layer 2 so as to be peelable. It is a cured product of the product. Thus, since only the coating layer 3 is cured, it can be peeled off, and since the inner layer 2 is not cured, the surface layer of the inner layer 2 exposed to air by the peeling of the coating layer 3 is cured, The surface layer of the coating can be updated (FIG. 1).

In the composite coating film of the present invention, the coating layer 3 is formed when it is determined that the coating layer is surface-dried in a 23 ° C. atmosphere in accordance with the provisions of JIS K5600-3-2 (the Barotini method described later). Judge that it was done.

In the composite coating film of the present invention, the inner layer must be maintained in an uncured state. Therefore, it is necessary to confirm that the inner layer of the composite coating film in which the coating layer is formed is uncured.
In the present invention, as shown in FIG. 3, a rubber ball is dropped on the composite coating film, and the rebound resilience is determined from the rebound height of the ball. In the present invention, if the impact resilience at 23 ° C. is 11 to 55%, it is determined that the inner layer is uncured.
Even if the impact resilience is in the above range, if it is out of the range, it means that the curing of the inner layer is proceeding. That is, once the impact resilience in the above range is shown, it is desirable that the impact resilience after being exposed to air for a long time, for example after being exposed to air at 23 ° C. for 6 months, is in the above range.

The thickness of the coating layer 3 is in the range of 10 μm to 5 mm. By peeling off the coating layer 3, a coating layer 3 having a thickness in the range of 10 μm to 5 mm is newly formed on the surface layer of the inner layer 2, so that the inner layer 2 is equal to or more than the thickness of the coating layer 3 If it has thickness of this, peeling of the membrane | film | coat layer 3 can be performed once or more several times.

The composite coating film of the present invention can be used as a single-layer coating film, or can be used as a lower layer, and an upper coating is applied to the upper surface of the coating film, or an interior material such as an exterior material or wallpaper is applied to the upper layer. It can also be formed. The interior materials such as the top coat, exterior material, and wallpaper are not particularly limited, and those that are usually used can be used.

3. Manufacturing method of composite coating film The manufacturing method of the composite coating film of the present invention,
A step of applying the coating composition of the present invention on the substrate 1 to form a coating film made of an uncured body of the coating composition (FIG. 2a); and exposing the coating film made of the uncured body to the air The surface layer is cured by oxidative polymerization to form the coating layer 3, and the portion under the coating layer 3 is maintained in an uncured state to form the inner layer 2 (FIGS. 2b and c).
including.

More specifically, for example, the coating layer made of the uncured body is exposed to air at 5 to 150 ° C. for 1 day or 20 minutes or more to cure the surface layer by oxidative polymerization to form the coating layer 3. Since the oxidative polymerization inhibitor existing in the vicinity of the uncured surface layer volatilizes, the effect of promoting the oxidative polymerization reaction of the dryer is demonstrated, or the radical oxidative polymerization initiating function present in the system is exhibited and only the surface layer is cured. To do. On the other hand, since an oxidative polymerization inhibitor is present in the inner layer 2 below the coating layer, the effect of promoting the oxidative polymerization reaction of the dryer is inhibited, or the oxidative polymerization initiation function of radicals present in the system is suppressed, Further, the intrusion of oxygen is prevented by the hardened surface layer. Furthermore, the inner layer 2 is maintained uncured by the effect of the organic compound that obstructs the approach between the oxidatively polymerizable resins. The drying conditions can be adjusted as appropriate so that only the surface layer is cured.

Hereinafter, the present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to the following examples.

1. Preparation of coating composition [Example 1]
As a preparatory stage, alkyd resin varnish (Beccosol P-470-70; DIC Corporation) is heated to 40 ° C, and paraffin (melting point 42-44 ° C) (Wako Pure Chemical Industries, Ltd.) is heated to 70 ° C. Polyethylene (Neowax L (melting point 95-115 ° C.) (Yasuhara Chemical Co., Ltd.)) was heated to 130 ° C. to be in a liquid state. While the alkyd resin varnish heated to 40 ° C. was stirred with a disper, liquid paraffin and polyethylene were mixed. Then, a dryer protective agent (2-butanone oxime (Tokyo Chemical Industry Co., Ltd.)) and a dryer (cobalt naphthenate / mineral spirit solution (Co: 6%)) (Wako Pure Chemical Industries, Ltd.) were mixed in order, and 300 rpm For 5 minutes. Each component was blended according to Table 1.
From the atomic weight of cobalt: 58.93 and the molecular weight of 2-butanone oxime: 87.12, the number of moles of the dryer protective agent was calculated per mole of the metal element in the dryer.
After completion of the stirring, it was visually confirmed that the mixture was uniform to obtain a coating composition.

[Example 2]
Except not adding polyethylene, it mix | blended according to Table 1 and prepared the coating composition similarly to Example 1. FIG.

[Examples 3 to 5]
A coating composition was prepared in the same manner as in Example 1 except that polyethylene was not added and the ratio between the alkyd resin and the paraffin was changed and blended according to Table 1.

[Examples 6 to 8]
Alkyd resin varnish to alkyd resin varnish (Beckosol EL-8001; DIC Corporation), alkyd resin varnish (Beckosol EL-4501-50; DIC Corporation) or modified alkyd resin varnish (Stillesol J-719; DIC Corporation) Except having changed, it mix | blended according to Table 1, and prepared the coating composition similarly to Example 1. FIG.

[Examples 9 and 10]
Table except that alkyd-modified urethane resin (Burnac TD-125-HV; DIC Corporation) or acrylic resin (Acridic A-1300; DIC Corporation) is mixed into the base resin composition as a resin other than the alkyd resin. The coating composition was prepared in the same manner as in Example 1.

[Examples 11 and 12]
A coating composition was prepared in the same manner as in Example 1 except that paraffin (melting point: 50 to 52 ° C.) (Showa Chemical Co., Ltd.) and paraffin (melting point: 60 to 62 ° C.) (Kishida Chemical Co., Ltd.) was used. Prepared.

[Examples 13 to 15]
Except for using a dryer (cobalt octoate xylene solution (Co: 6%)) (DIC Corporation) or changing the amount of dryer (cobalt naphthenate mineral spirit solution (Co: 6%)) The coating composition was prepared in the same manner as in Example 1.

[Examples 16 to 19]
Except for using the dryer protective agent (cyclohexanone oxime (Wako Pure Chemical Industries, Ltd.)) or changing the addition amount of the dryer protective agent (2-butanone oxime (Tokyo Chemical Industry Co., Ltd.)), A coating composition was prepared in the same manner as in Example 1.
From the atomic weight of cobalt: 58.93, the molecular weight of 2-butanone oxime: 87.12, and the molecular weight of cyclohexanone oxime: 113.16, the number of moles of the dryer protective agent was calculated per mole of the metal element in the dryer. .

[Examples 20 to 22]
A coating composition was prepared in the same manner as in Example 1, except that the dryer protective agent was not added and eugenol (Wako Pure Chemical Industries, Ltd.) was added as a radical inhibitor.

[Examples 23 and 24]
A coating composition was prepared in the same manner as in Example 1 except that Eugenol (Wako Pure Chemical Industries, Ltd.) or tributyl phosphite (Wako Pure Chemical Industries, Ltd.) was used in combination as a dryer protective agent and a radical inhibitor. Was prepared.

[Example 25]
Mixing carbon black (MA100; Mitsubishi Chemical Corporation) and oily clay (CLAYTON ^R HY (BYK Additives & Instruments)) while stirring with a disper into alkyd resin varnish (Beccosol P-470-70; DIC Corporation) A premix paste was prepared and dispersed with a sand grind mill to prepare a dispersion paste.
As a preparatory stage, paraffin (melting point: 42 to 44 ° C.) (Wako Pure Chemical Industries, Ltd.) is set to 70 ° C. and powdered polyethylene (neo wax L (melting point: 95 to 115 ° C.) (Yasuhara Chemical Co., Ltd.)) is set to 130 ° C. Heated to liquid state.
While the dispersion paste heated to 40 ° C. was stirred with a disper, liquid paraffin and polyethylene were mixed. Then, a dryer protective agent (2-butanone oxime (Tokyo Chemical Industry Co., Ltd.)) and a dryer (cobalt naphthenate / mineral spirit solution (Co: 6%) (Wako Pure Chemical Industries, Ltd.) were mixed in order, and 300 rpm The ingredients were blended according to Table 4.
After completion of the stirring, it was visually confirmed that the mixture was uniform to obtain a coating composition.

[Example 26]
Titanium oxide (Ti-PURE R-706 (DuPont Co., Ltd.)), oily clay (CLAYTON ^R HY (BYK Additives & Instruments)) while stirring with an dispyd in alkyd resin varnish (Beccosol P-470-70; DIC Corporation) ) To prepare a premix paste, which was dispersed with a sand grind mill to prepare a dispersion paste.
As a preparatory stage, paraffin (melting point: 42 to 44 ° C.) (Wako Pure Chemical Industries, Ltd.) is set to 70 ° C. and powdered polyethylene (neo wax L (melting point: 95 to 115 ° C.) (Yasuhara Chemical Co., Ltd.)) is set to 130 ° C. Heated to liquid state.
While the dispersion paste heated to 40 ° C. was stirred with a disper, liquid paraffin and polyethylene were mixed. Then, a dryer protective agent (2-butanone oxime (Tokyo Chemical Industry Co., Ltd.)) and a dryer (cobalt naphthenate / mineral spirit solution (Co: 6%) (Wako Pure Chemical Industries, Ltd.) were mixed in order, and 300 rpm The ingredients were blended according to Table 4.
After completion of the stirring, it was visually confirmed that the mixture was uniform to obtain a coating composition.

[Example 27]
A coating composition was prepared in the same manner as in Example 1.

[Comparative Example 1]
As a preparatory stage, alkyd resin varnish (Beccosol P-470-70; DIC Corporation) is heated to 40 ° C, and paraffin (melting point 42-44 ° C) (Wako Pure Chemical Industries, Ltd.) is heated to 70 ° C. It was in a liquid state. While stirring the alkyd resin varnish heated to 40 ° C. with a disper, liquid paraffin was mixed. Then, a dryer protective agent (2-butanone oxime (Tokyo Chemical Industry Co., Ltd.)) and a dryer (cobalt naphthenate / mineral spirit solution (Co: 6%)) (Wako Pure Chemical Industries, Ltd.) were mixed in order, and 300 rpm For 5 minutes. Each component was blended according to Table 5.
From the atomic weight of cobalt: 58.93 and the molecular weight of 2-butanone oxime: 87.12, the number of moles of the dryer protective agent per mole of the metal element in the dryer was calculated.
After completion of the stirring, it was visually confirmed that the mixture was uniform to obtain a coating composition.

[Comparative Example 2]
A coating composition was prepared in the same manner as in Comparative Example 1 except that the blending ratio of paraffin to the base resin composition containing the alkyd resin varnish was increased.

[Comparative Example 3]
A coating composition was prepared in the same manner as in Comparative Example 1 without using a dryer and an oxidative polymerization inhibitor and blending them according to Table 5.

[Comparative Example 4]
A dryer was used but no oxidative polymerization inhibitor was used, and blending was carried out according to Table 5 to prepare a coating composition in the same manner as in Comparative Example 1.

[Comparative Example 5]
A coating composition was prepared in the same manner as in Comparative Example 1 without using paraffin and blending according to Table 5.

2. Formation of Composite Coating Film A composite coating film was formed in the following steps.
Step 1: Each coating composition of Examples 1 to 27 and Comparative Examples 1 to 5 is placed in a dish-like container (bottom area is about 34 cm ² ) having a radius of about 3.3 cm and a height of 2.5 mm, and a dry film thickness of 2.5. painted to mm (Fig. 2a)
Step 2: The prepared coating film was dried in a 23 ° C. atmosphere for one day or in a 120 ° C. atmosphere for 20 minutes to obtain a dry initial coating film (FIG. 2b).
Step 3: Dry in a 23 ° C. atmosphere for 6 months (FIG. 2c) and observe the change over time to confirm the formation of the desired composite coating film.

3. Evaluation of characteristics of composite coating film An evaluation test was performed on the obtained composite coating films under the following conditions. The evaluation results are shown in Tables 6 to 11.
(1) Surface drying property of composite coating [Purpose]
The cured state of the composite coating film surface is confirmed by the degree of drying.
[Test conditions]
In accordance with the provisions of JIS K 5600-3-2, about 0.5 g of barotini (nominal (dimension) aperture of 125 μm sieve) does not pass through the coating surface of the horizontally placed coated plate, and all 250 μm sieve is passed through. A fine glass ball classified so as to pass through was dropped from a height of 100 mm, and after 10 seconds, the test piece was tilted and lightly brushed to remove the barotini.
[Evaluation criteria]
+: When barotini can be removed without scratching, it is determined that the surface is dry.
-: If the coating film is scratched or filled with barotini and cannot be removed,
It is determined that the surface is not dried.
(2) Surface tackiness of composite coating [Purpose]
The cured state of the composite coating surface layer is confirmed by the degree of surface adhesion.
[Test conditions]
In a 23 ° C. atmosphere, the surface of the coating film was pressed with a finger, and the presence or absence of tackiness (tackiness) was evaluated.
[Evaluation criteria]
+: There was no tackiness.
-: Adhesive.
(3) Rebound resilience of composite coating [Purpose]
The coating film is composed of a viscous component and an elastic component. The elastic component stores the fall energy (kinetic energy) of this test, while the viscous component loses the energy. The technique of peeling multiple times is that the surface layer is reactively cured and the inside is uncured, and the key point is that the rebound resilience in this test is lower than that of a normal fully cured coating. Comparison of this value indicates that the interior is unreacted.
[Test conditions]
Rubber balls from a position of height H1 (70 cm) in an atmosphere of 23 ° C (material is silicone, spherical with a diameter of 2 cm and a weight of 5 g, JIS K 6253-2012 “Vulcanized rubber and thermoplastic rubber hardness The hardness measured in "How to obtain" was naturally dropped onto a coating film placed on a marble table, and the bounce height H2 of the rubber ball at that time was measured (FIG. 3). Using the height H1 as the denominator and the bounce height H2 as the numerator, the rebound resilience (%), which expresses the value as a percentage, was defined and evaluated based on the magnitude of the value. The number of tests was 3, and the average value was used. The film thickness of the coating sample A for measurement test was unified to 2.5 mm, and the influence of the film thickness was removed.
[Evaluation criteria]
Rebound resilience: 0 to 10%: The surface layer is not sufficiently cured.
Rebound resilience 11 to 55%: The surface layer is sufficiently cured, and the inner layer is in an uncured state.
Rebound resilience: 56% or more: The inside is too hard.
(4) Internal fluidity of composite coating [Purpose]
Clarify the effect of the flow inhibitory substance on the flow of the coating film.
[Test conditions]
In a 23 ° C. atmosphere, the prepared coated plate was tilted to 90 ° and allowed to stand for 1 hour, and then the presence or absence of flow (deformation) was visually confirmed.
[Evaluation criteria]
+: No cracks or wrinkles were observed in the coating layer, and no distortion occurred in the entire coating film.
-: Cracks or wrinkles are observed in the coating layer, or the entire coating film is distorted.
(5) Peelability of film layer [Purpose]
The coating layer proved from the above test that the surface layer is cured, and it is confirmed whether the coating layer can be peeled off.
[Test conditions]
The part where the coating film adhered to the inner wall of the dish-shaped container is cut off with a cutter knife, cellophane tape (Cellotape CT-24; Nichiban Co., Ltd.) is attached to a part of the coating film surface, and the cellophane tape is pulled up (Fig. 4). . The peeled film thickness was measured with an electronic caliper.
[Evaluation criteria]
++: When all of the coating layer can be peeled off from the inner layer without being cut off in the middle, peeling is possible.
+: Even if the coating layer is cut off in the middle, finally, all of the coating layer can be peeled off from the inner layer, so that peeling is possible.
-: When at least a part of the coating layer cannot be peeled off from the inner layer, the peeling is impossible.

Any of the coating films prepared using the coating compositions of Examples 1 to 27 had an appropriate impact resilience even after 1 day at 23 ° C. or after 20 minutes at 120 ° C. and after 6 months at 23 ° C. Rate (11-55%), good surface drying and surface tackiness. The internal fluidity was good after the initial coating, no cracks or wrinkles were formed on the coating film surface, and no deformation occurred.
For example, when the impact resilience was measured immediately after peeling the film layer of the composite coating film after 6 months using the coating compositions of Examples 1 and 2, it was 7.9% and 10.1%, respectively. It was confirmed that the inner layer was maintained in an uncured state even after 6 months of drying.

On the other hand, the coating films prepared using the coating compositions of Comparative Examples 1 to 5 lacking any of the components contained in the coating composition according to the present invention were completely cured to the inner layer by 6 months, The rebound resilience increased to about 56-70%.

If the coating composition of the present invention is used, a composite coating film comprising a cured film layer and an uncured inner layer can be obtained, and this film layer can be peeled off and the coating film surface layer can be updated multiple times. Therefore, by applying the coating composition of the present invention, for example, even in a place where repainting is difficult, it is possible to always maintain a state free from damage or contamination, or to maintain a function imparted to the coating film. .

DESCRIPTION OF SYMBOLS 1 Substrate 2 Uncured part of coating film 3 Cured part of coating film Cellophane tape A Coating film sample for measurement having a coating film thickness of 2.5 mm

Claims (11)

A coating composition comprising: a base resin composition comprising an oxidation polymerizable resin; an organic compound having a melting point of 5 to 150 ° C .; a dryer; and an oxidation polymerization inhibitor comprising at least one of a dryer protective agent and a radical inhibitor. . The organic compound content of 10 to 100% by weight with respect to 100% by weight of the base resin composition and the metal element content in the dryer with respect to 100% by weight of the solid content of the oxidative polymerizable resin are 0.001 to 1.%. Including an effective amount of the dryer to be 5% by weight,
When the oxidative polymerization inhibitor includes any one of a dryer protective agent and a radical inhibitor,
Containing from 0.5 to 4 moles of the dryer protective agent per mole of metal elements in the dryer; or
Containing 0.01 to 2.0% by weight of the radical inhibitor with respect to 100% by weight of the oxidative polymerizable resin solid content; or
When the oxidative polymerization inhibitor includes both a dryer protective agent and a radical inhibitor,
When the dryer protective agent is contained in an amount of 0.5 to 4 moles per mole of the metal element in the dryer, the radical inhibitor is contained in an amount of 2.0% by weight or less based on 100% by weight of the oxidative polymerizable resin solid content. Or
When the dryer protective agent is contained in an amount of less than 0.5 mol with respect to 1 mol of the metal element in the dryer, the radical inhibitor is added in an amount of 0.01 to 2.0 wt. The coating composition according to claim 1, comprising: The coating composition according to claim 1, wherein the oxidation polymerizable resin is an alkyd resin that is a reaction product of a polybasic acid or polybasic acid anhydride, a fatty acid, and a polyhydric alcohol. The coating composition according to claim 1, wherein the oxidative polymerization inhibitor is a volatile substance having a boiling point of 300 ° C or lower. A composite coating consisting of a coating layer and an inner layer,
The inner layer is an uncured body of the coating composition according to any one of claims 1 to 4, and the coating layer is a cured body of the coating composition formed on the surface of the inner layer so as to be peelable. And
A composite coating film in which a surface layer of an inner layer exposed to air by peeling of the coating layer formed on the inner layer is cured by oxidation polymerization so that another coating layer can be peeled off. The composite coating film according to claim 5, wherein the coating layer is determined to be surface-dried based on the provisions of JIS K5600-3-2. The composite coating film according to claim 6, having a rebound resilience of 11 to 55%. 6. The composite coating film according to claim 5, wherein the thickness of the coating layer is in the range of 10 μm to 5 mm, and the thickness of the inner layer is equal to or greater than the thickness of the coating layer. The composite coating film according to claim 5, wherein the thickness of the another coating layer is in the range of 10 µm to 5 mm. It consists of a coating layer and an inner layer, and the coating layer is a method for producing a composite coating film that is detachably formed on the surface of the inner layer,
Applying a coating composition according to any one of claims 1 to 4 on a substrate to form a coating film comprising an uncured body of the coating composition; and applying the coating film comprising the uncured body to air. A composite coating film comprising a step of curing the surface layer by oxidative polymerization to form the coating layer, and maintaining a portion under the coating layer in an uncured state to form an inner layer by exposing Production method. The manufacturing method according to claim 10, wherein the thickness of the coating layer is in the range of 10 µm to 5 mm, and the thickness of the inner layer is equal to or greater than the thickness of the coating layer.

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