JP2976841B2 - Aqueous resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous resin composition and can be used mainly as a paint, a primer, an ink, an adhesive, and a sealing agent. In addition, the resin composition of the present invention can be used in combination with other aqueous resins such as aqueous urethane, acrylic, polyester, and epoxy, and a water-soluble resin depending on the application, so that it can be used as a modifier for a film-forming material. Can also be used.

[0002]

2. Description of the Related Art Conventionally, polypropylene, polyethylene,
And modified polyolefins obtained by modifying polyolefins such as propylene, copolymers of ethylene and α-olefins with unsaturated carboxylic acids or anhydrides thereof, and acid-modified chlorinated polyolefins obtained by chlorinating them are used as coating materials, primers, inks, etc. It is used for However, at present, since these resins are dissolved only in aromatic organic solvents such as toluene and xylene, a large amount of aromatic solvents must be used, and there is a problem in terms of safety and health and environmental pollution.

Therefore, Japanese Patent Application Laid-Open No. 1-153778 discloses
JP-A-1-256556, JP-A-2-28497
No. 3, JP-A-59-47244, and JP-A-2-47.
286724 discloses an attempt to produce an aqueous dispersion of a modified polyolefin. However, in these attempts, an aromatic organic solvent remains in the system, or when the object to be coated in coating or bonding is a polyolefin resin, the adhesion or water resistance is poor or the coating property is poor. There were drawbacks such as.

In Japanese Patent Application Laid-Open (JP-A) No. 3-182534, the performance of a coating film is improved by making a modified chlorinated polyolefin aqueous using a surfactant and then blending it with an aqueous polyurethane resin. However, since the water-soluble urethane resin and the surfactant are not reactive, the water causes the phenomenon that the activator component is eluted from the coating film and the water resistance is lowered due to the defect of the coating film which is considered to be caused by the elution.

In order to solve the above problems, Japanese Patent Laid-Open No. 6-14 / 1994
No. 5,286, discloses a technique in which a combination of a blocked isocyanate and an aqueous polyolefin-based resin has improved water resistance without impairing the adhesion to a substrate and the adhesion. However, since there is tack in the dried coating film of the aqueous resin composition containing the blocked isocyanate, there is a practical problem in applications such as paints and primers.

[0006]

As described above, since the conventional modified polyolefin resin composition is used as an organic solvent solution, there have been problems of solvent toxicity and environmental problems. Further, the aqueous resin composition containing a blocked isocyanate devised to solve them has a problem that tackiness remains in a coating film, though it has excellent adhesion and water resistance. An object of the present invention is to provide an aqueous resin composition that simultaneously solves these toxicity, environmental problems, and tackiness.

Further, in a water-based resin composition of a polyolefin or a modified polyolefin, adhesion and adhesion of a film formed by the water-based resin composition to a substrate are improved.
The purpose is to improve tackiness without impairing water resistance.

[0008]

Means for Solving the Problems In order to achieve the above object, the present inventors have developed an aqueous resin composition which is free from problems such as toxicity and pollution, is excellent in safety, and is excellent in adhesion, water resistance and tackiness. As a result of intensive studies, when preparing an aqueous resin composition containing a modified polyolefin resin and a blocked isocyanate compound, the glass transition temperature was 0 ° C or higher and 80 ° C or higher.
It has been found that the object can be achieved by using an aqueous resin composition characterized by containing a blocked isocyanate compound having a temperature of not more than 10 ° C. or less based on the total weight of the blocked isocyanate compound.

The modified polyolefin used in the present invention is
A modified polyolefin resin comprising one or more of a polyolefin modified by graft copolymerization of an unsaturated carboxylic acid or an acid anhydride thereof, a chlorinated polyolefin, and a polyolefin graft-copolymerized with a reactive monomer.

A modified polyolefin resin obtained by performing at least two types of modification among acid modification, chlorination modification, and modification with a reactive monomer can also be used.

The polyolefin used in the present invention may be a homopolymer of ethylene or propylene, or ethylene or propylene and another comonomer such as butene.
1, pentene-1, hexene-1, heptene-1, octene-1 and the like having 2 or more carbon atoms, preferably 2 to 6 carbon atoms.
It is a random copolymer or a block copolymer with an olefin comonomer, and a random copolymer is more preferable than a block copolymer. In addition, these comonomers are
More than one kind may be copolymerized. When a film is formed on a polypropylene substrate, the proportion of the propylene component is preferably at least 55 mol%, and if it is less than 55 mol%, the adhesion to the surface of a non-polar substrate such as polypropylene is poor, which is not preferred.

The chlorinated polyolefin is obtained by chlorinating the above polyolefin by a known method.

The acid-modified polyolefin is a polyolefin obtained by modifying the above-mentioned polyolefin with an α, β-unsaturated carboxylic acid or an acid anhydride thereof by a graft reaction.

Α, β used for modification of polyolefin
-Examples of unsaturated carboxylic acids or acid anhydrides thereof include maleic acid, fumaric acid, itaconic acid, citraconic acid, allylsuccinic acid, mesaconic acid, aconitic acid, and acid anhydrides thereof. The amount of the α, β-unsaturated carboxylic acid or its anhydride to be graft-copolymerized is preferably 1 to 20% by weight, and when it is 1% by weight or less, the stability when dispersed in water is deteriorated, and 20% by weight or more. In this case, the graft efficiency becomes poor, which is uneconomical. Particularly preferably, it is 2 to 15% by weight. Further, the number average molecular weight of the resin obtained by graft copolymerizing the α, β-unsaturated carboxylic acid or its acid anhydride is preferably from 3,000 to 35,000,
If it is less than 3,000, the cohesive strength is insufficient and the adhesion to the polyolefin resin is poor. If it is more than 35,000, the operability when dispersing in water is unfavorable.
In order to make the molecular weight fall within this range, it is possible to select the molecular weight of the raw material and the conditions for performing the graft reaction, and it is also possible to perform the graft reaction after the molecular weight of the raw material is reduced. The number average molecular weight can be measured by GPC (gel permeation chromatography).

The method of graft-copolymerizing an α, β-unsaturated carboxylic acid or an anhydride thereof with a polyolefin may be carried out by a known method. Is preferably carried out by a method of graft copolymerization.

In the present invention, a basic substance, an alcohol, a surfactant, a reactive surfactant, and a radical reaction initiator can be added to make the modified polyolefin resin or the modified polyolefin resin containing the blocked isocyanate aqueous. .

The basic component is added to ionize hydrophilic groups such as a carboxyl group and a sulfone group to improve dispersion in water, and to use a reactive surfactant and a non-reactive surfactant. In some cases, it is not necessary to use the agent when the agent is already neutralized with a base. As the base, sodium hydroxide, potassium hydroxide, ammonia, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, ethanolamine, propanolamine, diethanolamine, N-methyldiethanolamine, dimethylamine, diethylamine, triethylamine, N , N-dimethylethanolamine, 2-dimethylamino-2-methyl-1-propanol, 2-amino-2-methyl-1-propanol,
Morpholine and the like can be exemplified. The degree of hydrophilicity of the resin also varies depending on the type of base used, so it is necessary to select it appropriately depending on the conditions. The amount of the basic substance to be used is suitably in the range of 0.3 to 1.5 times the equivalent of the carboxyl group of the acid-modified polyolefin, and preferably 0.5 to 1.2 times. In addition, in the addition of a basic substance, it is necessary to control the pH of the aqueous resin composition to be prepared to around neutral depending on the stability of the blocked isocyanate compound to be added.

The reactive surfactant used in the present invention may be one generally used as a reactive surfactant or a reactive emulsifier, but an alkylphenyl group as a hydrophobic group and a polyoxyalkylene as a hydrophilic group. Those having a group are preferred. Among them, alkylpropenylphenol ethylene oxide 20 mol adduct, 3
0 mol adduct, 50 mol adduct, (Aqualon RN-
20, RN-30, RN-50; Daiichi Kogyo Pharmaceutical Co., Ltd.
Ammonium sulfate salt of an alkylpropenylphenol polyethylene oxide 10 mol adduct,
Ammonium sulfate ammonium salt of the same 20-mol adduct (Aqualon HS-10, HS-20; Daiichi Kogyo Seiyaku Co., Ltd.)
1-alkylphenoxy-3- (2-propenyl) oxy-propan-2-ol ethylene oxide adduct or a sulfate thereof (Riasorp NE-10, N
E-20, NE-30, NE-40, SE-10N; manufactured by Asahi Denka Kogyo).

Examples of the surfactant that can be used include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, polyoxyethylene polyhydric alcohol fatty acid ester, and polyoxyethylene propylene polyol (pluronic type). Nonionic surfactants such as alkylolamide, sorbitan alkyl ester, polyglycerin ester, alkyl sulfate ester salt, alkyl phenol sulfonate salt, sulfosuccinate ester salt and the like, and carboxylate, phosphate ester salt and the like. Anionic surfactants that can be used, amphoteric surfactants such as alkyl betaines and alkyl imidazolines, and mixtures of two or more of these can be used.
The addition amount of the surfactant component, which is a combination of the non-reactive surfactant and the reactive surfactant, is 1 to 100 parts per 100 parts of the modified polyolefin. The required amount depends on the type and amount of

The reactive monomer which can be used in the present invention includes acrylic acid, methacrylic acid, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, acrylonitrile, acrylamide, hydroxyethyl acrylate and the like. Acrylic monomers, conjugated diene monomers such as butadiene, isoprene and chloroprene; halogenated olefin monomers such as vinyl chloride and vinylidene chloride; aromatic monomers such as styrene and divinylbenzene; vinyl ester monomers such as vinyl acetate; methyl maleate And maleic anhydride.

The reaction initiator for initiating the reaction between the reactive monomer and the reactive surfactant may be a known one, and may be a water-soluble initiator such as azobisisobutyronitrile, hydrogen peroxide, potassium persulfate. However, oil-soluble initiators can also be used. Further, a redox-based initiator can be used. They may be used in combination.

Examples of the organic peroxide include benzoyl peroxide, dicumyl peroxide, lauroyl peroxide, 2,5-dimethyl-2,5-di (t-
(Butylperoxy) -hexyne-3, di-t-butyl peroxide, t-butyl hydroperoxide, t
-Butylperoxybenzoate, cumene hydroperoxide and the like, which can be selected and used depending on the reaction temperature and reaction time.

The blocked isocyanate compound in the present invention refers to a compound having an isocyanate group in its molecular structure and having the isocyanate group blocked by a suitable blocking agent.

Blocked isocyanate is an isocyanate compound having two or more isocyanate groups in one molecule, for example, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, decamethylene diisocyanate, m-phenylene diisocyanate, p-phenylene. Diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-
Naphthylene diisocyanate, 4,4 ', 4 "-triphenylmethane triisocyanate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethyl-4,
Isocyanates such as 4'-diphenylene diisocyanate, m-xylylene diisocyanate, p-xylene diisocyanate, isophorone diisocyanate, lysine isocyanate, and the above-mentioned isocyanate compound excess, for example, ethylene glycol, propylene glycol, 1,3-butylene glycol, Addition reaction or addition polymerization reaction with low molecular weight polyols such as pentyl glycol, 2,2,4-trimethyl-1,3-pentanediol, hexamethylene glycol, cyclohexanedimethanol, trimethylolpropane, hexanetriol, glycerin, and pentaerythritol. , Polyisocyanate having a burette structure, polyisocyanate having an allophanate bond , An isocyanate compound obtained by blocking isocyanates with isocyanurate structure with a blocking agent.

Examples of the blocking agent include phenols such as phenol and cresol, alcohols such as methanol, benzyl alcohol and ethylene glycol monomethyl ether, active methylenes such as methyl acetoacetate and dimethyl malonate, acetanilides and amides. Acid amides, other imides, amines, imidazoles, ureas, carbamates, imines, oximes, mercaptans, sulfites, lactams, and the like.

That is, the blocked isocyanate referred to in the present invention includes a compound generally called a blocked isocyanate, a masked isocyanate, a reactive urethane or the like. Glass transition temperature of 0 ° C or higher and 80
Specific examples of the blocked isocyanate compound at a temperature of not more than ° C include Duranate X-1429 and 1487 (manufactured by Asahi Kasei Kogyo Co., Ltd.), Cleran UI (manufactured by Sumitomo Bayer Urethane), and the like.

In the aqueous resin composition of the present invention, it is necessary to use a blocked isocyanate compound having a glass transition temperature of 0 ° C. to 80 ° C. in an amount of 10 to 90% by weight based on the total weight of the blocked isocyanate compound. If the glass transition temperature is lower than 0 ° C, the tackiness is not improved, and if the glass transition temperature is higher than 80 ° C, the film-forming property is reduced. For usage,
10% by weight based on the weight of all blocked isocyanate compounds
If the amount is smaller, the tackiness is not improved, and if it is more than 90% by weight, the surface property of the coating is reduced. The glass transition temperature can be measured by DSC (differential scanning calorimeter).

The ratio of the total amount of the blocked isocyanate compound to the modified polyolefin is preferably in the range of 1:20 to 10: 1. However, the content of the isocyanate group contained in the blocked isocyanate compound and the dryness of the modified polyolefin, the surface active component, etc. The optimum ratio can be determined by the amount of the functional group which reacts with the isocyanate group such as the hydroxyl group and the carboxyl group contained in the component remaining in the coating film after the treatment.

In the aqueous resin composition of the present invention, it is effective to dissociate the blocking agent after water evaporates in the drying step, so that the dissociation temperature of the blocking agent is preferably higher than the temperature set in the drying step. .

The above-mentioned blocked isocyanate, even if it is not water-dispersible or water-soluble in itself, can be made water-soluble by any method such as addition of a water-miscible organic solvent or a surfactant, or formation of a hydrophilic protective colloid. I just need.

In the present invention, in the step of adding and blending the blocked isocyanate to the modified polyolefin resin, the modified polyolefin resin is dissolved in a solvent and the blocked isocyanate compound is added to the solution. Or an aqueous modified polyolefin resin and an aqueous blocked isocyanate compound.

In the aqueous resin composition of the present invention, a dissociation catalyst for accelerating the deblocking reaction can be used, if necessary.

The resin composition of the present invention dispersed in water in this manner has excellent adhesion to polyolefins, and is excellent not only as a primer for painting and bonding, but also as a vehicle resin for aqueous coatings and aqueous adhesives. And a binder resin for aqueous inks. Furthermore, the aqueous resin composition of the present invention may optionally contain a rust-preventive pigment,
Pigments such as color pigments and extenders, and various additives such as flow aids, surface conditioners, primary rust inhibitors, defoamers, preservatives, and fungicides can also be added and mixed in necessary amounts.

Further, another aqueous resin, for example, an aqueous resin such as a urethane resin, an epoxy resin, an acrylic resin, a phenol resin, an amino resin, a polybutadiene resin, an alkyd resin, and a silicone resin may be blended.

When a film is formed using the aqueous resin composition according to the first, second, third or fourth aspect of the present invention, the film is preferably 80 to 80% in order to deblock and promote the reaction between isocyanate and other active hydrogen during the formation of the film. Heat treatment is performed at 200 ° C. for 1 minute to 2 hours. The optimum value of the treatment conditions is set according to the deblocking conditions of the blocked isocyanate to be used, the type and the amount of the deblocking catalyst to be used.

[0036]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Prototype Example 1) In a four-necked flask equipped with a stirrer, a cooling tube, a thermometer and a dropping funnel,
300 g of a propylene-α-olefin copolymer (75 mol% of a propylene component, 20 mol% of an ethylene component, 5 mol% of a 1-butene component, and a number average molecular weight of 25,000) is heated and dissolved in 700 g of toluene. 115 ° C
While stirring, 13 g of maleic anhydride and 12 g of di-t-butyl peroxide as a radical generator were added dropwise over 2 hours, and aging was performed for 3 hours. After cooling to room temperature after the reaction, the reaction product was poured into 20 L of acetone and purified to obtain a maleic anhydride graft copolymer having a graft amount of 2.1% by weight.

(Trial Production Example-2) In a four-necked flask equipped with a stirrer, cooling tube, thermometer and dropping funnel,
Propylene-butene-ethylene copolymer (propylene component 68 mol%, butene component 24 mol%, ethylene component 8
(Mol%, number average molecular weight: 68,000) 300 g was heated and melted, and then 40 g of maleic anhydride and 5 g of dicumyl peroxide as a radical generator were added to the system for 3 hours while maintaining the temperature of the system at 180 ° C. with stirring. The reaction was performed dropwise for 3 hours. After cooling to room temperature after the reaction, the reaction product was poured into 20 L of acetone and purified to obtain a maleic anhydride graft copolymer having a graft amount of 9.2% by weight. The weight average molecular weight measured by GPC is 2
6,000. In the measurement of the weight average molecular weight, a column TSK-GEL was attached to Tosoh HPLC-8020, and the sample was dissolved in THF (tetrahydrofuran).
The measurement was performed at 40 ° C., and the molecular weight was determined from a calibration curve prepared using a polystyrene standard sample.

(Trial Example-3) Blocked isocyanate compound A (Duranate X-1487; Asahi Kasei Corporation)
, Glass transition temperature 1 ° C), blocked isocyanate compound B (Duranate X-1406; Asahi Kasei Corporation)
(Glass transition temperature -18 ° C.).
It was made aqueous by the method described in JP-A-16817. Specifically, to 50 g of the blocked isocyanate compound A and 50 g of the blocked isocyanate compound B, 4 g of polyoxyethylene alkyl allyl ether (Neugen EA177; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added and mixed well. This mixture was stirred with a homomixer at a rotation speed of 3000 rpm while blocking partially saponified polyvinyl alcohol (P).
VA-217EE; Kuraray Co., Ltd.) 80 g of 5% aqueous solution
Was added over 10 minutes and stirred for 10 minutes. afterwards,
88 g of water was added over 10 minutes, and stirring was continued for 10 minutes to obtain an aqueous blocked isocyanate having a solid content of 30%.

(Example-1) In a four-necked flask similar to that of Trial Production Example-1, 100 g of the maleic anhydride graft copolymer obtained in Trial Production Example 1 was heated and melted at 120 ° C. After adding 15 g of morpholine, 10 g of a 10 mol adduct of 1-alkylphenoxy-3- (2-propenyl) oxypropan-2-ol ethylene oxide (Adecaria soap NE-10; manufactured by Asahi Denka Kogyo)
Was added, the temperature was lowered to 110 ° C., and water at 90 ° C. was gradually added to prepare an aqueous reaction solution. Then, 10 g of sodium persulfate as a radical reaction initiator was added thereto, and the mixture was stirred at 80 ° C. for 4 hours to carry out a polymerization reaction. After the reaction, 4 g of triethylamine was added to obtain an aqueous reaction solution (solid content: 30%). The aqueous reaction solution was subjected to a molecular weight cut-off of 5,000.
Treated with an ultrafiltration membrane for 48 hours and then reconcentrated to a solid content of 4
A 5% aqueous acid-modified polyolefin resin was obtained. The aqueous acid-modified polyolefin resin obtained and the aqueous blocked isocyanate obtained in Prototype Example-3 were mixed at a solid content of 2: 1 to obtain an aqueous resin composition.

Example 2 In a four-necked flask similar to that of Trial Production Example 1, 100 g of the maleic anhydride graft copolymer obtained in Trial Production Example 2 was heated and dissolved in 200 g of toluene at 110 ° C. After adding 10 g of butyl peroxyisopropyl carbonate and 9.6 g of morpholine, a toluene (120 g) solution of 10 g of an alkylpropenylphenol ethylene oxide 20 mol adduct (AQUARON RN-20; manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was taken over 3 hours. After dripping,
A post-reaction was carried out for 4 hours to carry out a graft copolymerization reaction. After the toluene contained in the reaction solution was distilled off under reduced pressure, 4 g of triethylamine and 20 g of propylene glycol monomethyl ether were added, and water was added with stirring to obtain an aqueous reaction solution (solid content: 25%). The aqueous solution was treated with an ultrafiltration membrane having a cut-off molecular weight of 5,000 for 48 hours and then concentrated again to obtain an aqueous acid-modified polyolefin resin having a solid content of 40%. The graft amount was 45% by weight based on the raw material resin. Prototype example of this aqueous acid-modified polyolefin resin
The aqueous blocked isocyanate obtained in 3 was used in a solid content of 5: 1.
To obtain an aqueous resin composition.

Example 3 In a four-necked flask similar to that of Prototype Example 1, 100 g of the maleic anhydride graft copolymer obtained in Prototype Example 2 was dissolved in 400 g of toluene. 25 g of Cleran UI; manufactured by Sumitomo Bayer Urethane, glass transition temperature 67 ° C.), 50 g of blocked isocyanate (Duranate X-1355; manufactured by Asahi Kasei Corporation, glass transition temperature: -18 ° C.), 40 g of ethanol, polyethylene oxide nonylphenyl ether (NS) -212; manufactured by NOF Corporation) and 5 g of morpholine. Set the temperature to 50 while stirring.
The addition of water at 50 ° C. and the distillation under reduced pressure were repeated three times, and the solvent was replaced with water to obtain an aqueous resin composition (solid content: 25%).

(Example-4) Chlorinated polypropylene resin (Supercron 803 MW; manufactured by Nippon Paper Industries Co., Ltd., chlorine content 29.5%, solid content wt% 20% toluene solution)
After heating 500 g to 110 ° C. and adding 9.6 g of morpholine, 5 g of polyethylene oxide nonylphenyl ether (NS-212; manufactured by NOF Corporation) was added. After the toluene was distilled off under reduced pressure, 20 g of ethylene glycol was added, and water was added with stirring at 100 ° C. to obtain an aqueous resin composition (solid content: 40%). The obtained aqueous chlorinated polyolefin resin and the aqueous blocked isocyanate obtained in Prototype Example-3 were mixed at a solid content of 3: 2 to obtain an aqueous resin composition.

(Example-5) A polyolefin obtained by oxidatively degrading the raw material polyolefin used in Prototype Example 2 (MW = 3)
100 g of an acid-modified polyolefin resin obtained by using a low-viscosity acid-modified polyolefin resin (MW = 12,000, graft amount: 9.6 wt%) obtained by substituting it with 200 g of toluene at 60 ° C. After adding 50 g of the blocked isocyanate used in Prototype Example-3, 5 g of polyethylene oxide nonylphenyl ether (NS-212; manufactured by NOF Corporation) was added. After the toluene was distilled off under reduced pressure, 20 g of ethylene glycol was added, and water was added with stirring at 100 ° C. to obtain an aqueous resin composition (solid content: 40%).

(Comparative Examples 1-2) An aqueous blocked isocyanate (Duranate X-1328; manufactured by Asahi Kasei Kogyo Co., Ltd., glass transition temperature -18 ° C) with respect to the aqueous acid-modified polyolefin resin prepared in Examples 1 and 2 Was mixed at a solids ratio of 2: 1 and water was added with stirring to obtain an aqueous resin composition having a solids content of 30%.

Comparative Example 3 In Example 3, a maleic anhydride graft copolymer, a blocked isocyanate (Cleran UI; manufactured by Sumitomo Bayer Urethane, glass transition temperature 67 ° C.), a blocked isocyanate (Duranate X-1355; Asahi Kasei) Industrial Co., Ltd., glass transition temperature-
Aqueous resin composition was obtained by adding 50 g, 5 g and 100 g respectively at 18 ° C.).

(Comparative Example 4) An aqueous blocked isocyanate (Duranate X-1429; Asahi Kasei Corporation) was used for the aqueous acid-modified polyolefin resin prepared in Example 1.
(Glass transition temperature: 1 ° C.) at a solid content of 2: 1 and water was added with stirring to obtain an aqueous resin composition having a solid content of 30%.

Table 1 shows the adhesion test results, the gasoline resistance test results, the water resistance test results and the tack test results of the aqueous dispersions of Examples 1 to 5 and Comparative Examples 1 to 4 after standing for one month. Indicated. The test method is as follows.

The aqueous resin compositions prepared in Examples 1 to 5 and Comparative Examples 1 to 3 were spray-coated on a polypropylene plate and dried at 80 ° C. for 15 minutes. Film thickness is 10-15 μm
m . Next, a two-pack type urethane top coat is applied, left at room temperature for 10 minutes, then forcibly dried at 80 ° C. for 30 minutes using a hot air drier, and then dried at 120 to 130 ° C. for 2 to 15 minutes.
It was heat-treated separately. After leaving the obtained coated plate at room temperature for one day, the coating film was tested.

(Adhesion test) A cut is made on the surface of the coating film to reach the substrate with a cutter, and 100 gobangs are made at 1 mm intervals, and a cellophane adhesive tape is adhered thereon and pulled five times in the 180 ° direction. It was peeled off and the number of remaining streaks was counted.

(Gasoline Resistance Test) A cut was made on the surface of the coating film to reach the substrate with a cutter, and the coating film was immersed in gasoline (Nisseki, high octane gasoline) for 4 hours, and the state of the coating film was visually observed.

(Water resistance test) 4 pieces of the coated plate were placed in warm water of 40 ° C.
After immersion for 8 hours, the state of the coating film was examined.

(Tack Property Test) The tack state of the coating film was examined by the touch with a finger.

[0054] (Symbols in the table) ；: very good, ○: good, Δ: slightly bad, ×: bad XX; very bad

[0055]

The aqueous resin composition of the present invention has excellent adhesion to polyolefin, good storage stability, and good flexibility of the coating film. Moreover, a tack-free coating film can be formed while maintaining adhesion and water resistance as compared with a conventional polyolefin-based aqueous resin composition containing a blocked isocyanate. In addition, since it can be made aqueous without using any aromatic organic solvent, it is excellent in terms of safety and health and environmental pollution.

────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification symbol FI C09J 175/00 C09J 175/00 (56) References JP-A-6-158016 (JP, A) JP-A-2-91167 (JP) , A) JP-A-62-149734 (JP, A) JP-A-59-113016 (JP, A) JP-A-51-114438 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) C08G 18/00-18/87 CA (STN) REGISTRY (STN)

Claims (5)

(57) [Claims] 1. A polyolefin modified by graft copolymerization of an unsaturated carboxylic acid or its anhydride, (B) a chlorinated polyolefin, and (C) a radical polymerizable polymer. In preparing an aqueous resin composition containing a modified polyolefin resin comprising one or more of a polyolefin obtained by graft copolymerizing a reactive monomer and a blocked isocyanate compound, the glass transition temperature is 0 ° C. or more and 80 ° C.
An aqueous resin composition comprising the following blocked isocyanate compound in an amount of 10 to 90% by weight based on the total weight of the blocked isocyanate compound. 2. The modified polyolefin resin is subjected to at least two types of modification of acid modification, chlorination modification, and modification with a reactive monomer as shown in (A), (B) and (C) of claim 1. The aqueous resin composition according to claim 1, which is a modified polyolefin obtained by the above method. 3. A film-forming product comprising the aqueous resin composition according to claim 1. 4. A sealing agent comprising the aqueous resin composition according to claim 1. 5. An adhesive comprising the aqueous resin composition according to claim 1 or 2.