JPH0718203A - Coating material composition - Google Patents

Abstract

PURPOSE:To obtain the composition which forms an undercoat for vacuum deposition excellent in adhesion to a hardly coatable resin, heat resistance, etc., by mixing a specified aminated (meth)acrylic (co)polymer, a mixture of (meth)acryloyloxy-containing monomers, and a photopolymerization initiator. CONSTITUTION:The composition is obtained by mixing 10-80 pts.wt. (co)polymer (A) of an aminated (meth)acrylic monomer of the formula (wherein R1 is H or methyl; R2 and R3 are respectively H or a 1-10C hydrocarbon residue; and n is an integer of 1 to 10), 10-80 pts.wt. mixture (B) of 20-100wt.% polyfunctional monomer having at least three (meth)acryloyloxy groups in the molecule and 80-0wt.% mono- or difunctional monomer having one or two (meth)acryloyloxy groups in the molecule, and 0.1-15 pts.wt. photopolymerization initiator (C), the total of components A, B and C being 100 pts.wt.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a coating material composition,
More specifically, the invention relates to a coating material composition used for forming an undercoat for vapor deposition, which has excellent adhesion, heat resistance, and surface smoothness, on a difficult-to-paint resin molded article by irradiation with active energy rays.

[0002]

2. Description of the Related Art Polyester resins having advantages such as productivity, moldability, heat resistance and weight reduction, for example, glass fiber reinforced polyethylene phthalate resin, polybutylene terephthalate resin and unsaturated polyester resin (BMC, SMC)
An undercoat layer (primer layer) for vapor deposition is formed on the surface of a resin molded product substrate such as
Metalized resin molded products that have been subjected to metallization treatment such as sputtering are used in a wide variety of fields such as various decorative products and reflectors. However, these polyester resins and unsaturated polyester resins have poor adhesion to paints and are difficult to apply. Therefore, various pretreatments have hitherto been carried out in order to improve the adhesion of the coating composition to the surface of these difficult-to-paint resins. Examples thereof include flame treatment method, corona discharge, oxidant treatment method, sandblast method, and radiation treatment method.

[0003]

However, such a method is difficult to apply depending on the shape of the article to be coated, it is difficult to obtain a uniform surface treatment, and the adhesiveness is not sufficiently satisfactory. Further, when these metallized resin molded products are used for a reflector or the like, performance such as heat resistance and surface smoothness is required.

[0004]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that a specific (meth) acrylic resin having good adhesion to a polyester resin or an unsaturated polyester resin is used. To the homopolymer or copolymer of the monomers, a coating composition containing a specific monomer mixture having excellent heat resistance and a photopolymerization initiator is applied, and irradiated with active energy rays to be cured. As a result, they have found that an undercoating layer for vapor deposition, which is excellent in adhesiveness, heat resistance, curability, and surface smoothness, can be obtained on the above-mentioned difficult-to-paint resin, and has reached the present invention. That is, the present invention provides (A) 10 to 80 parts by weight of a homopolymer or copolymer of a (meth) acrylic monomer having an amino group represented by the following general formula (I).

[Chemical 2] (B) 20 to 100% by weight of a polyfunctional monomer (b-1) having 3 or more (meth) acryloyloxy groups in one molecule, and 1 to 2 (meth) acryloyl in one molecule. Oxy group-containing 1-2 functional monomer (b-2) 80-0
10 to 80 parts by weight of a monomer mixture consisting of 10% by weight and 0.1 to 15 parts by weight of (C) a photopolymerization initiator (provided that the total amount of components (A) to (C) is 100 parts by weight). .) Is a coating material composition.

The homopolymer or copolymer of the amino group-containing (meth) acrylic monomer represented by the general formula (I) of the component (A) used in the present invention is a component for improving the adhesiveness. It can be obtained by employing a solution polymerization method, a bulk polymerization method, an emulsion polymerization method or the like in the presence of a radical polymerization initiator. Further, these homopolymers or copolymers having an amino group are used together with a hydrogen abstraction type initiator such as benzophenone or 2-ethylanthraquinone to improve the curability of the monomer mixture of the component (B). You can

Examples of the (meth) acrylic monomer having an amino group include N-methylaminomethyl (meth) acrylate, N-methylaminoethyl (meth) acrylate and N-methylamino-n-propyl (meth). ) Acrylate, N-methylaminoisopropyl (meth) acrylate, N-methylamino-n-butyl (meth) acrylate, N-methylaminoisobutyl (meth) acrylate, N-methylamino-t-butyl (meth) acrylate, N -Ethylaminomethyl (meth) acrylate, N
-Ethylaminoethyl (meth) acrylate, N-ethylamino-n-propyl (meth) acrylate, N-ethylaminoisopropyl (meth) acrylate, N-ethylamino-n-butyl (meth) acrylate, N-ethylaminoisobutyl (Meth) acrylate, N-ethylamino-t-butyl (meth) acrylate, N, N-
Dimethylaminomethyl (meth) acrylate, N, N-
Dimethylaminoethyl (meth) acrylate, N, N-
Dimethylamino-n-propyl (meth) acrylate,
N, N-dimethylaminoisopropyl (meth) acrylate, N, N-dimethylamino-n-butyl (meth) acrylate, N, N-dimethylaminoisobutyl (meth) acrylate, N, N-dimethylamino-t-butyl ( (Meth) acrylate, N, N-diethylaminomethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-diethylamino-n
-Propyl (meth) acrylate, N, N-diethylaminoisopropyl (meth) acrylate, N, N-diethylamino-n-butyl (meth) acrylate, N, N
-Diethylaminoisobutyl (meth) acrylate,
Examples thereof include N, N-diethylamino-t-butyl (meth) acrylate, and among them, N, N-dimethylaminoethyl methacrylate and N, N-diethylaminoethyl methacrylate are particularly preferable. These monomers are
One kind or two or more kinds can be used in combination.

In addition, examples of the monomer used for the copolymerization as required include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n
-Nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl (Meta)
Acrylate, methoxyethyl (meth) acrylate,
Acrylic esters such as ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate; 2-hydroxyethyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and other hydroxyalkyl (meth) acrylates; 2
2-hydroxyethyl (such as an adduct of hydroxyethyl (meth) acrylate and ethylene oxide, an adduct of 2-hydroxyethyl (meth) acrylate and propylene oxide, an adduct of 2-hydroxyethyl (meth) acrylate and ε-caprolactone). Hydroxyl group-containing vinyl monomers such as adducts of (meth) acrylate and organic lactones; styrene or styrene derivatives such as styrene, α-methylstyrene, pt-butylstyrene, vinyltoluene; (meth) acrylic acid, itaconic acid, maleic acid acid,
Unsaturated carboxylic acids such as fumaric acid; Polymerizable unsaturated nitriles such as (meth) acrylonitrile; Unsaturated carboxylic esters such as diethyl maleate, dibutyl maleate, dibutyl fumarate, diethyl itaconate, dibutyl itaconate; Examples thereof include vinyl esters such as vinyl acetate and vinyl propionate, and it is preferable that the copolymer contains an acrylic monomer having an amino group in an amount of 5% by weight or more from the viewpoint of adhesiveness of the cured film. These copolymerizable monomers can be used alone or in combination of two or more.

The proportion of the homopolymer or copolymer (A) of the (meth) acrylic monomer having an amino group is
10 to 8 in 100 parts by weight of the total amount of the components (A) to (C).
It is 0 part by weight, more preferably 30 to 70 parts by weight.
When the amount of the component (A) is less than 10 parts by weight, sufficient adhesiveness cannot be obtained, and when it exceeds 80 parts by weight, the heat resistance of the cured film,
The surface smoothness is reduced.

One of the components (B) used in the present invention
Polyfunctional monomer (b-1) having 3 or more (meth) acryloyloxy groups in the molecule and 1-2 functional groups having 1-2 (meth) acryloyloxy groups in one molecule The monomer mixture consisting of the monomer (b-2) shows good polymerization activity upon irradiation with active energy rays, and is used as an undercoat material for vapor deposition, which is excellent in heat resistance and surface smoothness in a resin product having poor coating properties. It is a component that forms a crosslinked cured film as a coat layer. Examples of the polyfunctional monomer (b-1) having 3 or more (meth) acryloyloxy groups in one molecule include, for example, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate,
Pentaerythritol tetra (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol tetra (meth) acrylate ) Acrylate, tripentaerythritol penta (meth) acrylate,
Examples thereof include tripentaerythritol hexa (meth) acrylate, tripentaerythritol hepta (meth) acrylate, tripentaerythritol octa (meth) acrylate and the like. Of the above, pentaerythritol tetraacrylate and dipentaerythritol hexaacrylate are particularly preferable. These polyfunctional monomers may be used alone or in combination of two or more.

Further, a mono- or di-functional monomer having 1 to 2 (meth) acryloyloxy groups in one molecule (b-
Examples of 2) include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, 2- Ethylhexyl (meth) acrylate, n
-Nonyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl (Meta)
Acrylate, methoxyethyl (meth) acrylate,
Ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2
-Monofunctional (meth) acrylate monomers such as -hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) acrylic acid, (meth) acryloylmorpholine; ethylene glycol di (meth) acrylate, 1,3 -Propylene glycol di (meth) acrylate, 1,4-heptanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, neopentyl glycol di (meth)
Acrylate, tetraethylene glycol di (meth) acrylate, 2-butene-1,4-di (meth) acrylate, cyclohexane-1,4-dimethanol di (meth) acrylate, hydrogenated bisphenol A di (meth)
Acrylate, 1,5-pentanedi (meth) acrylate, trimethylolethanedi (meth) acrylate, tricyclodecanedimethanol di (meth) acrylate,
Trimethylolpropane di (meth) acrylate, dipropylene glycol di (meth) acrylate, 1,3-
Butylene glycol di (meth) acrylate, 2,2-
Bis- (4- (meth) acryloxypropoxyphenyl) propane, 2,2-bis- (4- (meth) acryloxy (2-hydroxypropoxy) phenyl) propane, bis- (2-methacryloyloxyethyl) phthalate, etc. Examples of the bifunctional (meth) acrylate monomer include, but are not limited to, 2-ethylhexyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, 2-dicyclopentenoxyethyl acrylate, isobornyl. Acrylate, hydrogenated bisphenol A diacrylate, cyclohexane-1,4-dimethanol diacrylate and tricyclodecane dimethanol diacrylate are particularly preferred. These 1 to 2 functional monomers can be used alone or in combination of two or more.

A polyfunctional monomer (b-1) having 3 or more (meth) acryloyloxy groups in one molecule and 1 to 2 (meth) acryloyloxy groups in one molecule. The proportion of the bifunctional monomer (b-2) used is, in the monomer mixture, a polyfunctional monomer (b-1) / 1 to a bifunctional monomer (b-2) = 20 to. It is in the range of 100/0 to 80 (wt%), and preferably (b-1) / (b-2) = from the viewpoint of the balance of heat resistance, adhesion and surface smoothness of the cured film.
The range of 30 to 70/70 to 30 (% by weight) is preferable. The proportion of the component (B) used is 10 in total of the components (A) to (C).
0 to 80 parts by weight, preferably 30 to 70 parts by weight
If it is less than 10 parts by weight, sufficient heat resistance cannot be obtained, and if it exceeds 80 parts by weight, the adhesiveness of the cured film is lowered.

Examples of the photopolymerization initiator which is the component (C) used in the present invention include benzoin, benzoin monomethyl ether, benzoin isopropyl ether, acetoin, benzyl, benzophenone, p-methoxybenzophenone, diethoxyacetophenone and benzyldimethylketal. , 2,2-diethoxyacetophenone,
Carbonyl compounds such as 1-hydroxycyclohexyl phenyl ketone, methylphenyl glyoxylate, ethylphenyl glyoxylate, 2-hydroxy-2-methyl-1-phenylpropan-1-one and 2-ethylanthraquinone; tetramethylthiuram monosulfide ,
Sulfur compounds such as tetramethylthiuram disulfide;
Examples thereof include acylphosphine oxide such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide. These are used in one kind or a mixed system of two or more kinds. Among these, benzophenone,
2-Ethylanthraquinone is more preferred. The amount of the photopolymerization initiator used is 0.1 to 15 parts by weight, more preferably 1 to 10 parts by weight based on 100 parts by weight of the total amount of the components (A) to (C).
Parts by weight. If the amount of component (C) is less than 0.1 parts by weight, the curing will be insufficient, and if it exceeds 15 parts by weight, the adhesion of the cured coating will be reduced.

An organic solvent may be used in the composition of the present invention to adjust the viscosity to a desired value, if necessary. Examples of organic solvents include ketone compounds such as acetone, methyl ethyl ketone, and cyclohexanone; ester compounds such as methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, and methoxyethyl acetate; ether compounds such as diethyl ether, ethylene glycol dimethyl ether, and dioxane. Examples thereof include compounds; aromatic compounds such as toluene and xylene; aliphatic compounds such as pentane and hexane; halogenated hydrocarbons such as methylene chloride, chlorobenzene and chloroform.

Further, the composition of the present invention may contain additives such as a leveling agent, an antifoaming agent, an anti-settling agent, a lubricant, an abrasive, an anticorrosive and an antistatic agent.

The formation of the undercoat layer for vapor deposition on the resin-molded product having difficulty in coating is achieved by applying the coating material composition of the present invention on the surface of the resin-molded product and irradiating with active energy rays. The thickness of the undercoat layer is in the range of 1 to 40 μm in terms of the thickness of the cured film.

The coating composition may be applied by brush coating, spray coating, dip coating, spin coating,
Although methods such as curtain coating are used, coating workability,
From the viewpoint of smoothness and uniformity of the coating film, the spray coating method is preferable.

The active energy rays used for curing the composition of the present invention include ultraviolet rays, electron beams,
Examples include gamma rays.

The vapor deposition on the resin which is difficult to coat with the undercoat layer is carried out by a known vapor deposition method of a metal such as aluminum.

[0019]

EXAMPLES The present invention will be described in detail below with reference to Examples and Comparative Examples. In the following, all "parts" are "weight parts"
Means Further, various measurement evaluations in Examples and Comparative Examples were performed by the following methods.

1. Appearance of cured film The appearance of the composition after coating and curing was visually evaluated. ○: The surface is smooth and transparent. Δ: The surface is uneven and not smooth. ×: not smooth, whitening, cloudiness, and decrease in gloss are observed.

2. Adhesiveness Cross-cuts reaching the substrate at 1 mm intervals were put in the metallized sample, 100 grids of 1 mm ² were made, and a cellophane tape was adhered on the grid, and the grids were rapidly peeled off and the peeled grids were counted. ○: No peeling. △: Number of peeled 1 to 50 ×: Number of peeled 51 to 100

3. Heat resistance The metallized sample was placed in a hot air dryer at 150 ° C. for 24 hours, and the appearance was visually evaluated. 〇… No change. Δ: Cracks, whitening, cloudiness, and rainbow phenomenon are observed on a part of the coated plate. X: Cracks, whitening, cloudiness, and rainbow phenomenon are observed on the entire coated plate.

The abbreviations used in Examples and Comparative Examples are as follows:
The following compounds are represented. DPHA: dipentaerythritol hexaacrylate PETA: pentaerythritol tetraacrylate HBADA: hydrogenated bisphenol A diacrylate CHDMDA: cyclohexane-1,4-dimethanol diacrylate DCPEA: 2-dicyclopentenoxyethyl acrylate MA1: N, N- Diethylaminoethyl methacrylate homopolymer, weight average molecular weight 3.0 × 10 ⁴ MA2: styrene / isobornyl methacrylate / N, N-dimethylaminoethyl methacrylate (3
0/40/30) copolymer, weight average molecular weight 3.0 × 1
0 ⁴ MA3: N, N-diethylaminoethyl methacrylate / methyl methacrylate / styrene / dicyclopentanyl methacrylate (20/20/20/40) copolymer, weight average molecular weight 3.0 × 10 ⁴ BNP: benzophenone 2EAQ: 2 -Ethylanthraquinone

Examples 1 to 6 and Comparative Examples 1 to 4 Curing liquids were prepared at the compounding ratios shown in Tables 1 and 2, and unsaturated polyester resin plates (Showa High Polymer Co., Ltd., trade name Rigolac BMC, RNC420) were prepared. Spray coating was applied so that the cured film thickness was 20 μm. Next, the organic solvent is volatilized by heating, and then a high pressure mercury lamp is used in the air, and the wavelength is 340 to 3
The cured coating film (primer layer) was formed by irradiating with energy having an integrated light amount of 80 nm of 2000 mJ / cm ² .
Aluminum was vapor-deposited on the substrate thus treated by a vacuum vapor deposition method to obtain a metallized resin plate. The evaluation results of the obtained metallized resin plate are shown in Tables 1 and 2.

[0025]

[Table 1]

[0026]

[Table 2]

Examples 7 to 9 and Comparative Examples 5 to 6 Curing liquids were prepared at the compounding ratios shown in Table 3 to prepare glass fiber reinforced polyethylene terephthalate resin plates (Mitsubishi Rayon Co., Ltd.).
Manufactured by Dyanite (registered trademark) MD8030) by spray coating so that the cured film thickness was 20 μm. Next, the organic solvent is volatilized by heating, and then a high pressure mercury lamp is used in the air, and the accumulated light amount of wavelengths 340 to 380 nm is 20.
Irradiation with energy of 00 mJ / cm ² was performed to form a cured coating film (primer layer). Aluminum was vacuum-deposited on the substrate thus treated to obtain a metallized resin plate. Table 3 shows the evaluation results of the obtained metallized resin plate.

[0028]

[Table 3]

[0029]

The coating material composition of the present invention having the above-described constitution is applied to the surface of a resin having poor coating property (difficult to adhere) without pretreatment and is irradiated with active energy rays. It is possible to form an undercoat layer for vapor deposition, which has excellent heat resistance, adhesion, and surface smoothness, and as a result,
It is possible to obtain a metallized resin molded product having excellent heat resistance and adhesiveness.

Claims (1)

[Claims] 1. (A) 10 to 80 parts by weight of a homopolymer or copolymer of a (meth) acrylic monomer having an amino group represented by the following general formula (I): (B) 20 to 100% by weight of a polyfunctional monomer (b-1) having 3 or more (meth) acryloyloxy groups in one molecule, and 1 to 2 (meth) acryloyl in one molecule. Oxy group-containing 1-2 functional monomer (b-2) 80-0
10 to 80 parts by weight of a monomer mixture consisting of 10% by weight and 0.1 to 15 parts by weight of (C) a photopolymerization initiator (provided that the total amount of components (A) to (C) is 100 parts by weight). A coating material composition comprising: