JPH06184248A - Coating resin - Google Patents

Abstract

PURPOSE:To obtain a coating resin excellent in durability, delustering properties, scratch resistance and stain resistance and useful for automobiles, etc., by copolymerizing a specific silicone macromer with a specific styrene macromer and a specific vinyl-based monomer in a specific ratio. CONSTITUTION:This coating resin having 20-80 deg.C glass transition temperature is obtained by copolymerizing (A) 0.2-5wt.% one or more kinds of silicone macromers of formulae I and II [R1 and R3 are H or methyl; R2 is methyl, ethyl or phenyl; (m) is 0 or 1; (l) is 0-2 when (m) is 0 and Cl) is 2 when (m) is 1; X is chlorine, 1-10C alkoxy or acetoxyl, e.g. gamma-(meth) acryloyloxypropyltrimethoxysilane with (B) 0-10wt.% one or more kinds of macromers of formula III (R4 is H or methyl; R5 is 1-18C alkyl) and (C) 85-99.80wt.% other vinylic monomer copolymerizable with the components A or B, e.g. methyl (meth)acrylate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel coating resin, more specifically, it is useful for forming a matte coating film, and has a good coating performance with little change in the matting effect even after polishing. The present invention relates to a coating resin.

[0002]

2. Description of the Related Art In recent years, it has been used to finish the surface of a coating film into a matte coating film in order to improve its design. In order to finish a matte coating film, conventionally, silica powder or the like is often mixed with a top coating composition, but since the silica powder floats on the surface layer of the coating film, polishing the coating surface produces silica powder. It has the drawback that it is detached and the matte effect is reduced, and the scratch resistance and stain resistance are also reduced.

[0003]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a coating resin useful for forming a coating film which has the above-mentioned defect-free matting property and is excellent in scratch resistance, stain resistance and the like. Is to get.

[0004]

The present invention includes (a) the following general formula:

[0005]

[Chemical 3]

(Wherein R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ is a methyl group, an ethyl group or a phenyl group, m is 0 or 1, and l is an integer of 0 to 2 when m = 0. Yes, m =
In the case of 1, it is 2, and X represents a chlorine atom, an alkoxy group having 1 to 10 carbon atoms, or an acetoxy group. ) At least one silicon macromer 0.2-5
Weight% (b) The following general formula

[0007]

[Chemical 4]

(In the formula, R ₄ is a hydrogen atom or a methyl group, and R ₄ is
₅ represents an alkyl group having 1 to 18 carbon atoms. ) At least one macromer represented by
% By weight and (c) another vinyl-based monomer copolymerizable with the above components (a) and (b) 85-99.80
It is a coating resin obtained by copolymerizing a monomer consisting of wt%.

Examples of the silicon macromers represented by the above general formulas [I] and [II] used for constituting the coating resin of the present invention include, for example, γ- (meth) acryloyloxypropyltrimethoxysilane. , Γ- (meta)
Acryloyloxypropyltrichlorosilane, γ-
(Meth) acryloyloxypropyldimethylmethoxysilane, γ- (meth) acryloyloxypropyldimethylchlorosilane, 3- (2- (meth) acryloyloxyethoxy) propyltrimethoxysilane, 3- (2
-(Meth) -acryloyloxyethoxy) propyltrichlorosilane, 3- (2- (meth) acryloyloxyethoxy) propyldimethoxysilane, 3- (2-
(Meth) acryloyloxyethoxy) propyldimethylchlorosilane, 5-((meth) acryloyloxy)
Examples thereof include pentyltrimethoxysilane, 5-((meth) acryloyloxy) pentyltrichlorosilane, 5-((meth) acryloyloxy) pentyldimethylmethoxysilane, and 5-((meth) -acryloyloxy) pentyldimethylchlorosilane. Of these, γ- (meth) acryloyloxypropyltrimethoxysilane is most preferable because it is easily available and inexpensive. These compounds can be used alone or in combination of two or more.

The styrene macromer represented by the above general formula [III] is disclosed in, for example, JP-A-62-250012.
It can be obtained by polymerizing styrene as described in Japanese Patent Application Publication No. 1993-242242 in the presence of mercaptoacetic acid to synthesize a prepolymer having a carboxy group, and then reacting it with glycidyl methacrylate. These compounds can be used alone or in combination of two or more.

Other vinyl monomers copolymerizable with the component (a) and the component (b) used for constituting the coating resin of the present invention include, for example, (meth) acrylic acid. Methyl, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate,
I-Butyl (meth) acrylate, t (meth) acrylic acid
-Butyl, sec-butyl (meth) acrylate, glycidyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, (meth) Isobornyl acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, (meth)
(Meth) acrylic acid alkyl ester such as tridecyl acrylate; aromatic vinyl such as styrene, α-methylstyrene and vinyltoluene; polymerizable unsaturated nitriles such as (meth) acrylonitri; vinyl such as vinyl acetate and vinyl propionate Esters; N-methoxymethyl (meth)
N-alkoxy-substituted amides such as acrylamide and N-butoxymethyl (meth) acrylamide; glycidyl (meth) acrylate, (meth) allyl glycidyl ether, epoxy group-containing monomer of metaglycidyl (meth) acrylic acid ester; dimethylamino Basic monomers such as ethyl (meth) acrylic acid and diethylaminoethyl (meth) acrylic acid; (meth) acrylic acid, itaconic acid,
Carboxyl group-containing vinyl monomers such as fumaric acid, crotonic acid, maleic acid, maleic anhydride, itaconic anhydride, monomethyl itaconate, monobutyl itaconate, monomethyl maleate monob; light ester PA, light ester PM (Kyoeisha fat and oil) Manufactured by)
Phosphoric acid group-containing vinyl monomers such as Kayamer PM-21 (manufactured by Nippon Kayaku Co., Ltd.) can be mentioned. (Meth) acrylic acid 2 as the hydroxyl group-containing (meth) acrylic acid ester
To hydroxyethyl, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxy (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 2-hydroxyethyl methacrylate 1 mol adduct of ε-caprolactone, 2 mol adduct of ε-caprolactone to 2-hydroxyethyl methacrylate, 1 mol adduct of ε-caprolactone to 2-hydroxyethyl acrylate, ε to 2-hydroxyethyl acrylate -Addition products of 2-hydroxyethyl (meth) acrylate and organic lactones such as a 2 mol addition product of caprolactone. Also, an adduct of 2-hydroxypropyl (meth) acrylate and an organic lactone can be used. These may be used alone or in combination of two or more.

The component (a) represented by the general formula [I] or [II] used in the present invention imparts a matting effect to the coating film and imparts scratch resistance and stain resistance. And the amount used is in the range of 0.2 to 5% by weight in the resin. If it is less than 0.2% by weight, the matting effect is not sufficient, and the scratch resistance and stain resistance effects are reduced. Meanwhile, 5
If the content is more than weight%, the mechanical strength of the coating film and the coating performance (water resistance) will deteriorate.

Further, the other vinyl-based monomer (c) copolymerizable with the components (a) and (b) has an adhesiveness to an object to be coated,
It imparts weather resistance, chemical resistance, and solvent resistance.
The amount used is in the range of 85 to 99.80% by weight in the resin.

Further, the component (b) represented by the general formula [III] used in the present invention is a component useful in forming a matte coating film, and in terms of performance, solvent resistance and water resistance. To impart coating property and stain resistance to the coating film, and the amount used is in the range of 0 to 10% by weight in the resin.
If it exceeds, the adhesiveness may be lowered or the weather resistance may be lowered depending on the object to be coated.

The resin of the present invention is prepared by subjecting a monomer comprising the above-mentioned component (a), component (b) and component (c) to a known solution polymerization method, suspension polymerization method, bulk polymerization method, emulsion polymerization method or the like. It can be produced by radical polymerization by means of, and solution polymerization is particularly preferable from the viewpoint of ease of industrial production.

The resin of the present invention obtained by radical copolymerization has a weight average molecular weight of 10,000 to 100,0.
The range of 00 is preferable from the viewpoint of coating film performance and coating workability.

The resin of the present invention preferably has a glass transition temperature (Tg) in the range of 20 to 80 ° C. from the viewpoint of the drying property and weather resistance of the coating film. When Tg ° C is lower than 20 ° C, the drying property and hardness of the coating film are deteriorated, and when it is higher than 80 ° C, the flexibility of the coating film tends to be poor.

Matting paints using the resin of the present invention include colorants such as titanium oxide, carbon black and quinacridone;
Resins other than acrylic, such as alkyd resin, epoxy resin, and fibrous resin; matting agents such as silica powder and polyethylene wax; organic and / or inorganic thixotropic agents; surface modifiers such as silicone; UV absorption Auxiliary additives such as an agent, a light stabilizer, an antioxidant, a curing agent, a curing catalyst, a pigment anti-settling agent and the like can be selected as necessary and can be obtained by a general compounding method. The method for forming a coating film using the coating resin of the present invention is carried out by a known and commonly used method.
Generally, the film thickness is 10 to 50 after diluted with an appropriate organic solvent.
Spray painting with a spray gun in the range of about μ.

[0019]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, "part" in an Example and a comparative example represents a "weight part."

Synthesis of Resin for Paint A four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer was charged with 40 parts of n-BuOH and 40 parts of toluene, and the temperature in the flask was raised to 95 ° C. Next, 0.5 parts of silicon macromer, 6.8 parts of styrene,
55 parts of methyl methacrylate, n-butyl methacrylate 2
1.7 parts, n-butyl acrylate 15 parts, acrylic acid 1
Part, and a mixed solution of 0.5 part of azobisisobutyronitrile were added dropwise over 3 hours. 0.2 parts of azobisisobutyronitrile was added 3 times every hour. After 2 hours, 42 parts of toluene was added and the mixture was cooled. The heating residue was 45%, the weight average molecular weight was 52,000, the glass transition temperature was 65 ° C., and the acid value was 7.
7 mg KOH / g of acrylic copolymer A-1 was obtained. Table 1 shows the monomer composition and characteristic values of the acrylic copolymer.

Further, the monomer composition was changed as shown in Table 1 to change the acrylic copolymers (A-2 to A-5 and B-1 to B).
-5) was obtained. Table 1 shows those characteristic values.

[0022]

[Table 1]

Manufacture of Paints Using the acrylic paint resins shown in Table 1, the compositions shown in Table 2 were added to prepare paints P-1 to P-10.

Next, the same paint was applied to toluene / xylene / butyl acetate / ethyl acetate = 40/10/30/20 (weight).
After diluting with Ford Cup ^# 4 for 18 seconds with a thinner, spray coating it on an ABS resin plate (Mitsubishi Rayon Co., Ltd. product, Diapet (registered trademark)) so as to have a dry film thickness of 15 μ, and 10 minutes After leaving 60 to 80 ℃ ×
Dry for 20-25 minutes.

The results are shown in Table 3.

[0026]

[Table 2]

[0027]

[Table 3]

Gloss (60 degrees); JIS K 5400
Measured according to 6.4.

Dryability: After coating, drying and cooling, put gauze on it, and apply a load of 500 g on it, and
Leave for 4 hours.

The condition of the coating film after gauze is visually judged.

◯: Good Δ: Slightly bad ×: Poor Xylol resistance; Xylene was added to gauze, the surface of the coating film was rubbed 10 times, and the surface condition was visually judged.

◯: Good Δ: Swelling slightly ×: Swelling and peeling of coating film Warm water resistance; The coated test piece was immersed in warm water at 40 ° C. for 24 hours,
The hot water resistance was visually evaluated. ◯: No change Δ: Little swelling of coating film ×: Large swelling of coating film Weather resistance; Sunshine W-O-W using a Suga tester
The appearance after 800 hours was visually judged.

Contamination resistance: Hand cream was applied to the surface of the coating film with gauze, allowed to stand for 24 hours, wiped off with gauze, and the surface condition was visually observed.

[0034]

EFFECT OF THE INVENTION The coating resin of the present invention having the above-mentioned constitution has a main component which is a polymer component composed of a branch component derived from a macromonomer and a monomer unit copolymerized with the macromonomer. An acrylic resin in which the degree of polymerization of branch components and the content thereof are well controlled. Since this has a tendency to be oriented on the surface of the coating film, the resin for matting paints of the present invention has a matt gloss on the surface of the coating film as compared with the conventional one-pack type acrylic lacquer paint, and the matting effect is remarkably high. In addition to being excellent, it can exhibit good properties in terms of physical properties such as drying property, pencil hardness, xylol resistance, and hot water resistance, and is extremely useful for applications such as automobiles and light electrical appliances.

Claims (2)

[Claims] 1. (a) The following general formula: (In the formula, R ₁ and R ₃ are a hydrogen atom or a methyl group, R ₂ is a methyl group, an ethyl group or a phenyl group, m is 0 or 1, 1
Is an integer of 0 to 2 when m = 0, is 2 when m = 1, and X represents a chlorine atom, an alkoxy group having 1 to 10 carbon atoms, or an acetoxy group. ) At least one silicon macromer represented by the formula: 0.2-5 wt% (b) The following general formula: (In the formula, R ₄ is a hydrogen atom or a methyl group, and R ₅ is a carbon atom 1
~ 18 alkyl groups are shown. 0-10% by weight of at least one macromer represented by the formula (4), and (c) another vinyl-based monomer copolymerizable with the components (a) and (b) above 85-99.80.
A coating resin obtained by copolymerizing a monomer composed of 1% by weight. 2. The glass transition temperature (Tg) of the resin is 20 to
The coating resin according to claim 1, which is in the range of 80 ° C.