JPH01249828A - Composition for putty - Google Patents

Abstract

PURPOSE:To provide the subject composition composed of a specific epoxy resin, a polymercaptan curing agent, a tertiary amine-type basic catalyst and a pigment and having excellent quick-drying property as a automotive repair coating. CONSTITUTION:The objective composition can be produced by compounding (A) 5-80wt.% (preferably 10-60wt.%) of an epoxy resin having an epoxy equivalent of 140-450 (preferably 160-300), (B) 3-70wt.% (preferably 5-50wt.%) of a polymercaptan-type curing agent containing >=2 mercapto groups in one molecule on an average, (C) 0.03-10wt.% (preferably 0.05-7wt.%) of a tertiary amine-type basic catalyst, (D) 0-80wt.% (preferably 30-70wt.%) of a pigment and, as necessary, (E) an organic solvent, etc. The composition is applied to a substrate, cured, polished, coated further with a primer surfacer and a top and finish- coatings.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides an epoxy resin, a polymercaptan curing agent,
The present invention relates to a putty composition containing a tertiary amine basic catalyst and a filler as essential components, and a method for coating the same.

(Prior art) As a painting method for automobile repair, a putty composition for sheet metal is applied with a spatula or the like to areas that require correction such as dents, irregularities, and steps on the base sheet metal of an automobile, and after drying, it is applied with sandpaper. After sanding and smoothing, a primer surfer and top coat are applied.

The properties required of the sheet metal putty composition include (υ) excellent painting workability, (3) quick-drying properties that allow it to dry (cure) to the extent that it can be polished within 30 minutes at room temperature;
(4) It has excellent adhesion to the substrate, and (4) it has excellent finishing properties of 1-Limer Surfacer and top coat.

Conventionally, as a putty composition for sheet metal, a polyester putty composition is prepared by polymerizing and curing an unsaturated polyester putty composition containing an unsaturated polyester resin, a polymerizable unsaturated monomer, a filler, a stabilizer, a catalyst, etc. using a peroxide catalyst. However, since curing is a polymerization system and no by-product bottom is generated, thick coating is possible, and the curing speed can be adjusted using a catalyst and a peroxide catalyst to achieve quick drying. It is widely used because of its However, the polyester putty composition does not dry out depending on the seasons such as summer, spring and autumn, and
Atmosphere) Because the curing properties vary significantly depending on temperature fluctuations, it is usually necessary to produce three types of unsaturated polyester putty compositions with different amounts of catalyst depending on the season, which increases production costs and increases the production cost during that season. Unusable items must be stored until the next season, which makes them inconvenient to use. In addition, the polyester putty composition can satisfy the above-mentioned quick drying property (2) by adjusting the amount of peroxide catalyst, but the pot life of the composition is shortened and painting workability is poor. Become. In addition, the polyester putty composition undergoes volumetric shrinkage during curing, resulting in poor adhesion to the sheet metal, and furthermore, a hard and brittle cured product is formed, resulting in the problem that the cured product may peel off from the sheet metal due to impact, etc. there were. Friend, in addition to the above, when a lacquer-based glimmer surfer and top coat paint are applied to the surface of the putty formed from the polyester putty composition, a coating film with defects such as sagging and staining is formed. Problems such as these remained.

(Problems to be Solved by the Invention) The present invention aims to provide a putty composition and a method for applying the same that have excellent quick drying properties without deteriorating workability, adhesion, and finish quality of the top coat. It was made for the following purposes:

(Means for Solving a Problem) As a result of various studies on methods for overcoming such drawbacks, the present inventors have developed a putty containing polymercaptan as a curing agent and tertiary amine as a curing catalyst in an epoxy resin. The present inventors have discovered that the composition for use in this invention satisfies all of the above-mentioned drawbacks, and have completed the present invention.

That is, the present invention uses 5 to 80% by weight of an epoxy resin of 11140 to 450 per epoxy resin and 3 to 80% by weight of a polymercaptan curing agent.
70% by weight, tertiary amine citadel catalyst 0.03-10
The present invention relates to a putty composition having a heavy lid% and a test material of 0 to 50Nt%, and a method for coating the same.

The epoxy resin used in the composition of the present invention is epoxy resin
i140-45(), preferably 160-:(00 resin, specifically - is, for example, 2.21-bis(4-
hydroxyphenyl)propane (bisphenol A),
1. Polyglycidyl of polyphenols obtained by reacting polyphenols such as 1'-bis(4-hydroxyph) with epihalohydrin, or by reacting phenol novolak, which is a reaction product of phenol or cresol with formaldehyde, with epihalohydrin. Ethers; for example, polyglycidyl ethers of polyols such as ethylene glycol, glycerol, trimethylolpropane, pentaerythritol, neopentyl glycol; for example, phthalic acid, terephthalic acid, adipic acid,
Polyglycidyl esters of polybasic acids such as tetrahydrophthalic acid and hexahydrophthalic acid; polyglycidyl esters of unsaturated fatty acids such as lylunic acid dimer; polyglycidyl esters of unsaturated acids such as linseed oil and soybean oil Examples include esters, and in addition to the above, examples include epoxidized vinylcyclohexane, polyglycidyl in cyanurate, diglycidyl aniline, and the like. Among the above, the reaction product of bisphenol A or bisphenol F polyphenol and epichlorohydrin has excellent reactivity with polymercaptan curing agents, and its cured product has excellent adhesion to metal substrates and primer surfers. It is advantageous to use this material because it is easy to polish.

The above-mentioned epoxy resin must have an epoxy equivalent of 140 to 450; if the epoxy equivalent is less than 140, the cost to obtain it will be high; on the other hand, if the epoxy equivalent is greater than 450, the putty composition will The viscosity becomes high and the pot life becomes short, which adversely affects painting workability.

The epoxy resin can have a number average molecular weight in the range of 300 to 1800, preferably 300 to 1000,
If the number average molecular weight is less than 300, the adhesion to sheet metal will be poor, the physical properties of the cured product formed from the putty composition will be poor, and on the other hand, the number average molecular weight will be greater than 1800. This shortens the pot life and deteriorates the paint workability of the putty composition.

The blending ratio of the epoxy resin is 5 to 80%, preferably 10 to 60% based on the weight solid content of the putty composition.
If the blending ratio is less than 5% by weight, the adhesion to sheet metal will be poor, and the physical properties of the cured product formed from the coating composition will be poor; on the other hand, if the blending ratio is less than 80% by weight, If the amount is too large, the polishability of the cured product formed from the putty composition will be poor.

The polymercaptan curing agent used in the composition of the present invention is 1
As long as it has an average of at least two mercapto groups in its molecule, it can be selected from commercially available products without any particular restrictions. For example, adducts of excess low molecular weight dimercaptan and polyepoxide can be used. , a reaction product of polyepoxide and hydrogen sulfide, an esterified product of mercaptopropionic acid or mercaptoglycolic acid and a polyhydric alcohol, etc. 2 Specific examples of these include triethylene glycol bis(mercaptoacetate), triethylene glycol Bis(mercaptopropionate), triethylene glycol bis(mercaptobutyrate), 1,4-butanediol bis(mercaptoacetate), 1,4-butanediol bis(mercaptohexonate), neopentyl glycol bis(mercapto acetate), neopentyl glycol bis(
Mercaptooctanate), Glycerin Tris (Mercaptoacetate), Glycerin Tris (Mercaptopropionate), Glycerin Tris (Mercaptopentanate), Trimethylolpropane Tris (Mercaptoacetate), Trimethylolpropane Tris (Mercaptopropionate), Tris Methylolpropane tris (
Mercaptobutyrate), Trimethylolpropane Tris (Mercaptohexonate), Pentaerythryptotetrakis (Mercaptoacetate), Pentaerythryptotetrakis (Mercaptopropionate), Pentaerythritite Tetrakis (Mercaptoacetate), Pentaerythritrite Tetrakis ( Mercaptopropionate), Pentaerythritite Tetrakis (Mercaptobutyrate), Pentaerythritite Tetrakis (Mercaptopentanate), Pentaerythritite Tetrakis (Mercaptohexonate), Pentaerythritite Tetrakis (
mercaptooctanate), etc.

The polymercaptan curing agent is blended in an amount of 3 to 70% by weight, preferably 5 to 50% by weight, based on the weight solid content of the putty composition.

The above-mentioned blending ratio is generally such that the number of mercapto groups is 0.5 to 1.5, preferably 0.7 to 1.2 per epoxy group of the epoxy resin.

If the number of mercapto groups is less than 0.5, the adhesion to the sheet metal will be poor, the physical properties of the cured product formed from the putty composition will be poor, and the finished appearance of the top coat will be poor. If the number is more than 1.5, there will be a large amount of unreacted polymercaptan curing agent, which will give off a strong mercaptan odor, which is unfavorable in terms of environmental hygiene.Also, the hardness of the cured product formed from the putty composition will decrease, resulting in poor abrasiveness. Inferior.

The tertiary amine basic catalyst used in the composition of the present invention is used to promote the reaction between an epoxy group and a mercapto group, and specifically, triethylamine, tetramethylbutanediamine, tetramethyl Aliphatic amines such as pentanediamine, tetramethylhexanediamine, and triethylenediamine; alkanolamines such as dimethylaminoethanol, monoethanolamine, and dimethylaminopentanol; morpholines such as N-methylmorpholine and morpholine; 2-methylimidazole , 1-benzyl-2-methylimidazole, 2-methyl-4-ethylimidazole, 1-cyanoethyl-2
-Imidazoles such as methylimidazole, 1-cyano-ethyl-2-phenylimitasol, and 1-azine-2-methylimidazole; anilines such as dimethylaniline; and tris(dimethylaminomethyl)phenol.

The blending ratio of the tertiary amine basic catalyst is 0.03 to 10% by weight, preferably 0.05 to 7% by weight, based on the weight solid content of the putty composition. In addition, the above blending ratio is generally o to one epoxy group of the epoxy resin.
, o o s to 0.03 mol, preferably o, o o
s~0.02 mol is blended. If the blending ratio of the tertiary amine basic catalyst is less than 0.03% by weight, quick drying properties, polishing properties, physical properties, topcoat finish properties, etc. will be poor;
If there is more than 0% by weight, the pot life will be too short,
Paint workability is poor.

The pigments used in the composition of the present invention may be conventionally known coloring pigments, rust-preventing pigments, extender pigments, and hollow or ma-shaped Resins or inorganic substances can be used, specifically,
For example, coloring pigments such as titanium white, oxade yellow, Shanin blue, Shanin green, carbon black, and red iron; extender pigments such as calcium carbonate, clay, mica, Merck, and barium sulfate; antirust pigments such as strontium chromate, zinc stearate, and silica. Balloons, perlite balloons, resin balloons, glass fibers, etc. can be mentioned.

The blending ratio of the pigment is 0 to 80% by weight based on the weight solid content of the putty composition, preferably 30 to 70% by weight from the viewpoint of product cost, polishability, etc.

In addition to those mentioned above, the composition of the present invention may contain other detergents or additives such as organic solvents, fluidity regulators, and seasoning dispersants, if necessary.

The 11-1 paraboloid of the present invention is based on an epoxy resin, a polymercaptan curing agent, and a pigment added as necessary, and a tertiary amine based on a mixture of epoxy resin, polymercaptan curing agent, and pigment as needed. It can be applied to the object to be coated by adding a basic agent or a medium.

In the coating method of the present invention, the above-mentioned putty composition is applied with a spatula to the parts of the sheet metal of an automobile that require correction, and after drying, the putty is sanded with water or air using #180 to #240 abrasive paper. This is done by applying a primer coat and a topcoat.

The above putty composition is generally applied to a thickness of 0.5 to 5 fi, preferably 1 to 3 m. In addition, the li1 condition of the putty composition is, for example, drying at 20° C. within 1 hour. As the above-mentioned Primer Surfacer, lacquer surfer, polyurethane surfer made of polyester or polyneedle polyol as a base resin and a polyurethane compound mixed therein as a crosslinking agent, etc. are applied, and as a top coat, Volatilized dry type paints such as nitrocellulose lacquer, acrylic lacquer, cellulose-modified acrylic lacquer, and acrylic polyurethane, and polymerized N-dried paints such as alkyd resin paints, acrylic-modified alkyd resin paints, and acrylic polyurethane paints are applied.

(Effects of the Invention) The putty composition of the present invention is stable because the reaction between the epoxy group of the epoxy resin and the mercapto group of the mercaptan curing agent hardly progresses at room temperature. It takes advantage of the property that when a tertiary amine is present as a catalyst, the reaction progresses rapidly and curing occurs.
When compared with conventional putty compositions, it has the following remarkable effects.

(1) When epoxy resin and mercaptan curing agent are mixed at a certain ratio, the curing properties do not change significantly depending on the drying atmosphere temperature, so there is no need to prepare three types of putty compositions depending on the season. Manufacturing costs are low and handling is easy.

(2) Even if the ambient temperature is high, the pot life of the putty composition is long, so the coating workability is excellent.

(3) Since volumetric shrinkage does not occur during curing, adhesion to the base material (sheet metal) is excellent.

(4) The cured putty has excellent physical properties because it is a reaction product of an epoxy resin and a mercaptan curing agent.

(5) Furthermore, the cured putty has excellent abrasive properties, and even when primer surfer and top coat are applied on it, it does not produce defects such as sagging or rifting, and has an excellent finished appearance and the next top coat is formed. can.

The present invention will be explained in further detail by giving examples. Note that the "section" described in the examples is based on one bond.

Example 1 (a) Epoxy resin putty base (component) (part) EP-4
520TX varnish 400 [manufactured by Asahi Denka Kogyo ■, trade name, bisphenol A type epoxy resin; epoxy-1ii210-230] Tancal 280 talc
300 titanium white
20 The above composition was dispersed using a roll mill to obtain an epoxy resin putty base.

(b) Mercaptan curing agent (component) (part) EH-3
16400 [manufactured by Asahi Denka Kogyo ■, trade name, pentaerythritoltetrakis (3-mercaptogropionate), S
H value 7.5] Tancal 300 talc
300 The above composition was dispersed in a roll mill to obtain a mercaptan curing agent.

Next, (a) 100 parts of epoxy resin putty base, (b)
50 parts of a mercaptan curing agent and (c) EH-30 [manufactured by Asahi Denka Kogyo ■, as a tertiary amine curing promoter]
Product name: tris(dimethylaminomethyl)phenol]
Example 2 to obtain the composition of Example 1 by mixing 0.3 parts
4 Compositions of Examples 2 to 4 were obtained in the same manner as in Example 1 except that component (c) in Example 1 was varied from 0.5 to 4.0.

Example 5 The epoxy resin in the Al component of Example 1 was replaced with Epiclon S.
-129 (manufactured by Dainippon Ink Company, trade name, bisphenol F type epoxy resin, epoxy equivalent: 170-190) was produced in the same manner as in Example 1, and the composition of Example 5 was obtained. .

Comparative Example 1 Poly putty [manufactured by Kansai Paint ■, trade name, unsaturated polyester putty base, standard type] and BPO curing agent,
A composition of Comparative Example 1 was obtained by mixing 100 parts to 2 parts, respectively.

Comparative Example 2 The putty base of Comparative Example 1 was used as a quick-drying type, except for the following: Comparative Example 1
It was used in the same way.

Test Method Pot Lie 7: The total weight of each sample of Examples and Comparative Examples was weighed into a 502 polycup, and the time until gelation after mixing for 30 seconds was defined as pot life.

Curing time: The total weight of each sample of Examples and Comparative Examples was weighed on a 1002 glass plate, mixed with a wooden spatula for 30 seconds, coated on a mild steel plate to a thickness of 2 cm, and then measured by pencil hardness. Please note that the time when HB is reached is the curing time.

Adhesion and physical properties: After drying the sample applied to the mild steel plate for 3 days at each test temperature shown in Table 1, the test piece was bent at 90 degrees and the physical properties were determined from cracks and peeling on the bent surface. , adhesion was investigated.

The above test results are shown in Table-1.

Claims (1)

[Claims] 1. Epoxy resin having an epoxy equivalent of 140 to 450 5 to 8
0% by weight, polymercaptan curing agent 3-70% by weight,
A putty composition comprising 0.03 to 10% by weight of a tertiary amine basic catalyst and 0 to 80% by weight of a pigment. 2. A coating method for automobile refinishing, which comprises applying the putty composition according to claim 1 to a substrate, polishing the substrate after curing, and then sequentially applying a primer surfer and a top coat.