JPH0446968A - Paint resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition which exhibits very good adhesiveness to galvanized steel sheet by mixing an epoxy acrylate resin having a specified acid value, a filler, and a vinyl monomer at a specified ratio. CONSTITUTION:The title composition is obtained by mixing 20-45wt.% epoxy acrylate resin having an acid value of 15-70KOHmg/g [e.g. one obtained by reacting an epoxy resin with (meth)acrylic acid or a partial polybasic acid ester of a hydroxyalkyl (meth)acrylate and reacting the hydroxyl groups in the molecule with a polybasic acid]; 40-65wt.% filler (e.g. talc); and 5-20wt.% vinyl monomer (e.g. styrene). The use of this composition for putty remarkably improves the adhesion to galvanized steel sheet and makes it possible to apply a top coating material thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides an epoxy acrylate resin composition useful as a putty composition for automobiles and vehicles.

[Prior Art] Conventionally, as putty for automobiles and vehicles, ■nitrified cotton type ■acrylic type ■amino alkyd type ■urethane type ■unsaturated polyester resin type are known.

Each base material putty has its advantages and disadvantages.Putty compositions that are diluted with organic solvents have the drawbacks of thinning and cracking due to the organic solvent volatilizing during curing, and the inability to thicken them. In the case of urethane-based putty compositions, there is a problem that the drying time is longer and it takes more time to prepare the base.

Among these, unsaturated polyester resin putty compositions can be used to thicken the putty because the viscosity can be adjusted using ethylenically unsaturated monomers instead of using almost no organic solvents. In addition, by using a redox catalyst, 1.
It has the advantage of being able to freely adjust the drying time and saves a lot of labor in the pre-painting process, so it is used in many practical applications.

[Problems to be Solved by the Invention] However, in recent years, galvanizing has been applied to steel plates for vehicles for the purpose of rust prevention1, and in the case of unsaturated polyester resin putty, it is difficult to adhere to such treated steel plates. This has resulted in a significant decrease in the properties of the paint, causing problems in practical use, and the occurrence of blisters after painting (1) and peeling of the paint film are increasing. As a countermeasure against this problem, attempts have been made to treat galvanized steel sheets with a brimer treatment using phosphoric acid or the like before painting, but this is still insufficient1, and a solution to this problem is needed.

[Means for Solving the Problem] As a result of intensive research to solve the problem, the present inventors found that (A) an epoxy acrylate resin with an acid value of 15 to 70 KOH+*9/9, or the resin and the air. Mixture with dry unsaturated polyester resin 20-45% by weight, (B) filler 40-65% by weight, (C) vinyl monomer 5-20%
The present invention was completed based on the discovery that a composition having a ratio of % by weight exhibits extremely good adhesion to galvanized steel sheets.

The composition of the present invention will be explained in detail below.

First, the epoxy acrylate resin (A) used in the present invention has an acid value of 15 to 70 KOHm9/9, preferably 25
Must be ~55KOf119/9. If the acid value is less than 15 KOFIm9/9, the adhesion to the galvanized tone plate will be insufficient.1, or 70 KOHa+9/
If it is 9 or more, curing and drying properties and storage stability are reduced, and both are poor in practical use.

Examples of the epoxy resin include bisphenol A type, bisphenol F type, hydrogenated bisphenol A type, halogenated bisphenol A type, polyvalent glycidyl ester type, peracetic acid oxidized type, and polyphenol type.

The epoxy acrylate resin having the above acid value is prepared by first reacting an epoxy resin with acrylic acid, methacrylic acid, or a polybasic acid partial ester of hydroxyalkyl (meth)acrylate. The reaction is carried out according to a conventional method at about 80 to 130°C, and the epoxy groups in the epoxy resin react with the carboxyl groups of each of the above monomers. Two moles of each monomer are used per mole of epoxy groups in the epoxy resin.

Polybasic acid partial esters of hydroxyalkyl (meth)acrylates include hydroxymethyl acrylate, hydroxy ester acrylate, hydroxypropyl acrylate,
Hydroxyl group of (meth)acrylic acid hydroxy such as hydroxymethyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, maleic acid (anhydride), phthalic acid (anhydride), tetrahydrophthalic anhydride, 3-
It is an ester reaction product with the carboxyl group of a polybasic acid such as methyltetrahydrophthalic anhydride, and the molecule contains at least one oxirane group that can react with the oxirane group of the epoxy resin.
4 carboxyl groups must remain.

Next, in order to introduce a predetermined amount of carboxyl groups into the epoxy acrylate resin obtained above, the resin is further reacted with a polybasic acid. The reaction temperature is selected from about 100 to 130°C. Hydroxyl group in epoxy acrylate resin 1
A practical amount of the polybasic acid per mole is 0.15 to 0.7 mole.

As the polybasic acid, unsaturated polybasic acids such as maleic acid, itaconic acid, tetrahydrophthalic acid, and 3-methyltetrahydrophthalic acid are used, and if necessary, saturated polybasic acids such as phthalic acid and succinic acid are also used. can do.

In the present invention, the objective can of course be achieved by using (A) alone, but approximately 0.05 to 1 part of known putty resins such as air-drying unsaturated polyester resins and alkyd polyester resins are used in combination for 1 part of epoxy acrylate resin. It is also possible to do so.

Air-drying unsaturated polyester resin is a condensation product of polybasic acid, polyhydric alcohol and polyhydric alcohol allyl ether, or a condensation product of polybasic acid, polyhydric alcohol and animal and vegetable oil or their fatty acids and dimer acids. be.

As the polybasic acid, an unsaturated acid is usually used, and a saturated acid is used in combination if necessary.

Examples of unsaturated acids include maleic anhydride, maleic acid,
Examples of saturated acids include fumaric acid, itaconic anhydride, itaconic acid, etc.; examples of saturated acids include phthalic anhydride, phthalic acid, terephthalic acid, isophthalic acid, het acid, adipic acid, tetrahydrophthalic anhydride, trimellitic acid, trimellitic anhydride,
Examples include pyromellitic acid, pyromellitic anhydride, 4-methylcyclohetylene-12,3 tricarboxylic anhydride, trimesic acid, and the like.

In addition, polyhydric alcohols that can be polycondensed with nucleic acids include:
Ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, bisphenol dioxypropyl ether, 1,3-butylene glycol, 2,3-butylene glycol, neopentyl glycol, trimethylolpropane, trimethylolethane, penta erythritol,
Examples include glycerin.

Specific examples of the polyhydric alcohol allyl ether include pentaerythritol triallyl ether, trimethylolpropane diallyl ether, glycerin monoallyl ether, trimethylolethane diallyl ether, and glycerin diallyl ether. Both are ethers containing at least one hydroxyl group in the molecule.

The allyl group content is 2 to 40 mol%, preferably 1 as polyhydric alcohol allyl ether, based on the polybasic acid component.
0 to 30 mol% is suitable. Examples of animal and vegetable oils or their fatty acids include linseed oil, soybean oil, coconut oil, and their fatty acids and dimer acids.

The coating material of the present invention combines the resin (A) with (B) filler and (C).
) Prepared by mixing with vinyl monomer.

(B) Fillers include calcium carbonate, clay, talc, mica, asbestos powder, finely divided silica, barium sulfate, zinc stearate, lithopone, titanium white, cyanine blue, chrome yellow, watching red, red iron, carbon black, and aniline. Examples include black.

(C) As the vinyl monomer, any of the known crosslinking monomers for unsaturated polyester resins can be used, including styrene, vinyltoluene, monochlorostyrene, diallyl phthalate, methyl methacrylate, vinyl acetate, and glycidyl methacrylate. It will be done.

(A) Epoxy acrylate resin, (B) filler, (
C) The mixing ratio of vinyl monomers is 20 to 45% by weight of (A), 40 to 65% by weight of (B), and 5 to 20% by weight of (C).

If the content of (A) in the above composition is 20% by weight or less, the curing property will be slow and the water resistant adhesion will be poor. 45% by weight
Above that, the viscosity becomes high (1) and the workability becomes poor. Also (B)
If the amount is less than 40% by weight, the water-resistant adhesion will be poor, and if it is more than 65% by weight, the workability will decrease. Furthermore, if (C) is less than 5% by weight, the curability and workability will be poor, and if it is more than 20% by weight, the water-resistant adhesion will be poor, making it impractical.

Other paint additives such as curing agents, curing accelerators, diluents, thermoplastic resins, etc. may be added as necessary.

As a curing agent, methyl ethyl ketone peroxide, cyclohexanone peroxide, benzoyl peroxide,
Examples include dicumyl peroxide and tertiary-butyl perbenzoate.

Examples of the curing accelerator include cobalt octenoate, cobalt naphthenate, manganese nanthenate, dimethylaniline, diethylaniline, and dimethylparatoluidine.

Examples of the diluent include ethyl acetate, toluene, xylene, methanol, ethanol, butanol, acetone, methyl isobutyl ketone, methyl ethyl ketone, cellosolve, noacetone alfur, and the like.

Thermoplastic resins include cellulose acetate butyrate, nitrocellulose, vinyl chloride, vinyl acetate resin,
Examples include vinyl acetate resin, acrylic resin and copolymers thereof, butylated melamine, butylated urea, and the like.

Other additives include phosphoric acid, tartaric acid, phosphorous acid, oils and fats, silicone oil, surfactants, paraffin wax, and the like.

[Effects of the Invention] The coating material of the present invention is particularly useful as a sealant for automobile putty or sheet metal putty for vehicles, primer for steel furniture, joints in buildings, sash wraps 1, glass insets, etc. Of course, it can also be used for general woodworking coatings. As the coating method, any means such as spray coating, spatula coating 1, brush coating, etc. can be adopted.

When used as a putty for automobiles, a top coat can be further applied. The top coat is a conventionally used colored paint or metallic paint, such as acrylic urethane resin, acrylic alkyd nitrified cotton resin, acrylic cellulose, acetate butyrate resin, or alkyd melamine resin.

[Example] Next, the coating material of the present invention will be described in more detail with reference to Examples. In the examples, "%" and "part" are based on weight, unless otherwise specified.

Example 1 1172 parts of Evototo (epoxy resin manufactured by Tobu Kasei Co., Ltd.) and 44 parts of acrylic acid were placed in a flask equipped with a stirrer and a reflux condenser.
7. Prepare 0.34 parts of hydroquinone and 40 parts of 2-methylimidazole, 80~! The mixture was reacted at 20° C. for 3 hours to obtain an epoxy acrylate resin.

Next, 183 parts of maleic anhydride was supplied to the flask, and 120 parts of maleic anhydride was added to the flask.
The reaction was continued for 2 hours at °C until the residual acid disappeared, and diluted with styrene 890@ to obtain a resin liquid with a solid content of 65% (solution viscosity at 20 °C was 970 cps).

The acid value of the carboxyl group-containing epoxy acrylate resin was 33.4 KOHu/9.

Styrene 6.5 parts, talc 54.4 parts, titanium oxide 5.5 parts, synthetic iron black 02 to 32 parts of the above resin liquid
2 parts of cobalt octenoate (containing 8% cobalt) were added, and the mixture was kneaded in a kneader to produce a putty for automobiles. 0% and was applied to a polished galvanized steel plate with a spatula to a thickness of 500 μm.

The metal adhesion (normal bending, water-resistant bending, heat-resistant needle bending, tensile shear strength) and hardness (Shore D) of the obtained coating film were measured.

The measurement method is as follows.

◎Normal bending: Bend the painted board 2 hours after painting,
Determine adhesion.

■Heat-resistant bending: Judge the adhesion of the coated plate after heat treatment at 110°C for 30 minutes.

◎Waterproof bending: Judge the adhesion of the painted board after being immersed in water for one day.

■Tensile shear strength: According to JISK esso ◎Hardness (Shore D): Measured 24 hours after painting.

The results are shown in the table.

Example 2 The same experiment as in Example 1 was conducted except that methacrylic acid was used instead of acrylic acid.

Examples 3-4 Using 105 parts of maleic anhydride in Example I,
Acid value 20, 1 KOH@g/9 (Example 3),
The acid value was adjusted to 50.0 using 305 parts of maleic anhydride.
The same experiment as in the same example was conducted except that each sample was changed to KOtla+9/9 (Example 4).

Examples 5 to 7 (A), (B), (C) during production of putty in Example 1
The same experiment as in the same example was conducted by changing the mixing ratio of ).

Example 8 Instead of acrylic acid in Example 1, 224 parts of acrylic acid,
The same experiment as in the same example was carried out except that 223 parts of a partial ester of 2-hydroxyethyl acrylate and tetrahydrophthalic anhydride were used.

Control Examples 1 to 2 In Example 1, the acid value of the epoxy acrylate resin was 1 OKOHmg/g (Control Example 1), and 80 KO
The experiment was conducted by changing to h9/9 (Control Example 2).

[Effects] In the present invention, by using a composition containing an epoxy acrylate resin with a specific acid value for putty, the adhesion to galvanized steel sheets is significantly improved.

Procedural amendment dated September 9, 1991 2 Name of the invention Resin composition for paint 3 Person making the amendment Relationship to the case Patent applicant Address 9-6 Nozaki-cho, Kita-ku, Osaka (zip code 53o) 4 , column for detailed description of the invention in the specification subject to amendment

Claims (1)

[Claims] 1. (A) 20-45% by weight of an epoxy acrylate resin with an acid value of 15-70 KOHmg/g, (B) 40-65% by weight of a filler, (C) 5-5% by weight of a vinyl monomer. A resin composition for paint comprising a proportion of 20% by weight. 2. The composition according to claim 1, wherein (A) is a mixture of an epoxy acrylate resin having an acid value of 15 to 70 KOHmg/g and an air-drying unsaturated polyester resin. 3. (A) is produced by reacting an epoxy resin with a polybasic acid partial ester of (meth)acrylic acid or hydroxyalkyl (meth)acrylate, and further reacting the hydroxyl group in the molecule with the polybasic acid. The composition according to claim 1 or 2.