JPH0776663A - Curable coating material composition - Google Patents

Abstract

PURPOSE:To obtain the composition useful for electric part items, etc., curable with UV rays, providing a coating film having excellent alkali solubility, hole sealing properties, etching resistance and smoothness, comprising a specific compound, an acrylic copolymer, a leveling agent and a photopolymerization initiator. CONSTITUTION:This compound comprises (A) 10-80 pts.wt. of a compound of formula I ((m) is 1-4; (n) is >=2; R is residual part after removal of OH from n-hydric alcohol), (B) 20-70 pts.wt. of a compound containing one carboxyl group and one (meth)acryloyl group in one molecule, (C) 0-20 pts.wt. of a carboxyl group-containing acrylic copolymer, (D) 0-0.5 pts.wt. of a leveling agent and (E) 0.1-10 pts.wt. of a photopolymerization initiator (with the proviso that the total of the component A to the component C is 100 pts.wt.). A polyester polyacrylate obtained by reacting a polybasic acid such as phthalic acid with a polyhydric alcohol such as ethylene glycol, for example, should preferably be used as the component A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is applied to a base material having fine irregularities and then exposed to ultraviolet rays to dissolve the alkali solubility,
The present invention relates to a curable coating material composition capable of forming a crosslinked cured coating film having excellent sealing properties, etching resistance and smoothness.

[0002]

2. Description of the Related Art Electronic materials such as printed wiring boards and semiconductor elements generally require precision and fine advanced processing techniques, and the ultraviolet exposure method is the mainstream of the etching process in the production line at present. Miniaturization of device dimensions,
In response to demands for improved processing accuracy, etching resists with high sensitivity (response efficiency of chemical reaction by light) and high resolution (especially low swelling during etching) are preferred. In recent years, there has been a demand for an etching resist material which, when it has fine irregularities, follows the irregularities and covers it without deterioration of smoothness and generation of bubbles.

However, in the currently used etching resist material, since the viscosity and surface tension of the coating material are high, it is not possible to sufficiently cover the fine irregularities of the base material, resulting in generation of bubbles and deterioration of smoothness. There are drawbacks.

Further, in the case of using a large amount of organic solvent like the current product, ignition, explosion, and
Since there is a risk of fire and the like, a flame retardant chlorine-based solvent such as trichlorethylene has been used as a solvent for diluting a resist. However, in recent years, it has been pointed out that these chlorine-based solvents may cause air pollution, and there is a trend toward the prohibition of their use as resist solvents in the near future due to legal regulations. For this reason, the UV-curable paint is being changed to a solvent-free system, but the smoothness, sealing property and alkali solubility after etching of the coating film formed by the paint are insufficient, and the level of practical application is reached. The current situation is that it has not yet reached.

[0005]

DISCLOSURE OF THE INVENTION An object of the present invention is to cure a coating film applied on a substrate having fine irregularities by ultraviolet irradiation, alkali solubility of the coating film, sealing property, etching resistance, smoothness. It is intended to provide a coating material composition capable of forming a crosslinked cured coating film having excellent properties.

Another object of the present invention is to provide a coating material composition which is solvent-free and can form a crosslinked cured coating film which is ultraviolet curable and has excellent smoothness.

[0007]

That is, the curable coating material composition of the present invention comprises (a) a compound 10 represented by the following formula:
~ 80 parts by weight,

[Chemical 2] (B) 20 to 70 parts by weight of a compound having one carboxyl group and one (meth) acryloyloxy group in one molecule, (c) 0 to 20 parts by weight of a carboxyl group-containing acrylic copolymer, (D) 0 to 0.5 part by weight of a leveling agent, and (e) 0.1 to 10 parts by weight of a photopolymerization initiator,
(However, the total of the components (a) to (c) is 100 parts by weight.) The curable coating material composition is characterized in that.

[0008]

The curable coating material composition of the present invention is obtained by using the compound of (a) in combination with the carboxyl group-containing monomer of (b) and the acrylic copolymer having an acidic group of (c). It has become possible to improve the etching property and at the same time exhibit good alkali solubility.

In the curable coating material composition of the present invention,
The compound (a) is used in the range of 10 to 80 parts by weight.
However, the total of the components (a) to (c) is 100 parts by weight. If the amount of (a) used is less than 10 parts by weight, the crosslinkability of the coating material is lowered and the etching resistance is lowered. Also,
A cured coating film formed from a coating material in which the amount of (a) used exceeds 80 parts by weight has low alkali solubility.

An example of the compound (a) represented by the formula (1) is obtained by reacting a polybasic acid such as phthalic acid or adipic acid with a polyhydric alcohol such as ethylene glycol or butanediol and acrylic acid. Examples thereof include polyester polyacrylate.

In the curable coating material composition of the present invention,
The compound (b) having one carboxyl group and one (meth) acryloyloxy group in one molecule is 20 to 70.
Used in the range of parts by weight. A cured coating film formed from a coating material used in an amount of less than 20 parts by weight has reduced alkali solubility, and a coating material composition exceeding 70 parts by weight has a high surface tension, resulting in a coating formed from the composition. The smoothness and sealing property of the film are deteriorated.

Specific examples of the compound (b) include a monoester reaction product of an acid anhydride or a dibasic acid and a hydroxyl group-containing (meth) acrylate. The dibasic acids or acid anhydrides used to synthesize the monoester reaction product include phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid and their anhydrides. Further, as the hydroxyl group-containing (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3
-Hydroxyalkyl (meth) acrylates such as hydroxypropyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; addition product of ethylene oxide to 2-hydroxyethyl (meth) acrylate;
Examples thereof include an addition product of propylene oxide to 2-hydroxyethyl (meth) acrylate.

In the curable coating material composition of the present invention, the acrylic copolymer (c) containing a carboxyl group is
It is used for the purpose of preventing cissing of the coating film, and has the feature of improving the alkali solubility of the coating film containing the acrylic copolymer (c) containing the carboxyl group. The use range is 0 to 20 parts by weight, preferably 3 to 2
0 parts by weight. The coating film formed from the coating material containing (c) in a proportion of more than 20 parts by weight has low smoothness. The acrylic copolymer (c) has a weight average molecular weight of 7,000.
~ 25,000, acid value 200 mgKOH / g or less, especially 3
It is preferably 0 to 100 mgKOH / g. A coating film formed from a coating material containing a polymer having a weight average molecular weight of less than 7,000 has low etching resistance, and a coating film formed from a coating material containing a polymer having a weight average molecular weight of more than 25,000 has low smoothness.

The acrylic copolymer (c) is composed of a carboxyl group-containing vinyl monomer and another vinyl monomer copolymerizable therewith. Examples of the carboxyl group-containing vinyl monomer include (meth) acrylic acid, itaconic acid, fumaric acid, crotonic acid, maleic acid, monomethyl itaconate, monobutyl itaconate, monomethyl maleate, monobutyl maleate and the like.

Other copolymerizable vinyl monomers include methyl (meth) acrylate and ethyl (meth).
Acrylate, n-propyl (meth) acrylate, n
-Butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
(Meth) acrylic acid esters such as lauryl (meth) acrylate, dodecyl (meth) acrylate, and stearyl (meth) acrylate; styrenes such as styrene, α-methylstyrene, vinyltoluene and their derivatives; (meth)
Polymerizable unsaturated nitriles such as acrylonitrile; vinyl esters such as vinyl acetate and vinyl propionate, and the like, but the hydroxyl group-containing vinyl monomer exemplified above as the hydroxyl group-containing (meth) acrylate (b); N-
N-alkoxy-substituted amides such as methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide; glycidyl (meth) acrylate, (meth) allyl glycidyl ether, metaglycidyl (meta) ) Epoxy group-containing monomers such as acrylic acid esters; basic monomers such as dimethylaminoethyl (meth) acrylic acid and diethylaminoethyl (meth) acrylic acid can also be used.

The acrylic copolymer (c) is not particularly limited, but it is preferable that it contains not only a carboxyl group but also a hydroxyl group. When it contains a hydroxyl group, alkali solubility is improved. The acrylic copolymer (c) has a hydroxyl value of 50 to 150 mgK.
It is preferably OH / g.

Acrylic copolymer (c) in the present invention
The polymerization method of, a solution polymerization method, a bulk polymerization method, a suspension polymerization method,
Although any known polymerization method such as emulsion polymerization method may be used, a polymer obtained by a solution polymerization method is particularly preferable. In the case of the solution polymerization method, the mixture of the above monomers is copolymerized in the presence of an organic solvent and a polymerization initiator. As the organic solvent, isopropyl alcohol, n-
A commonly used organic solvent such as butanol, toluene, xylene can be used, and a commonly used polymerization initiator such as azobisisobutyronitrile, benzoyl peroxide, cumene hydroperoxide can be used as a polymerization initiator. If necessary, a chain transfer agent such as 2-mercaptoethanol or n-octyl mercaptan can be used.

The leveling agent (d) used in the coating material of the present invention is used for the purpose of improving the smoothness and sealing property of the coating film, and a general surfactant can be used. . The amount used is 0 to 0.5 parts by weight based on 100 parts by weight of the total amount of the components (a) to (c),
It is preferably 0.01 to 0.5 parts by weight. If it exceeds 0.5 parts by weight, air bubbles are likely to be generated and the sealing property is deteriorated.

As the leveling agent (d), acrylic surfactants, silicone surfactants, fluorine surfactants and the like can be used. Specific examples thereof include Florad FC430 (Sumitomo 3M Limited). MEGAFACK F177 (manufactured by Dainippon Ink and Chemicals, Inc.); Dia-Aid AD-9002 (manufactured by Mitsubishi Rayon Co., Ltd.) and the like.

The photopolymerization initiator (e) used in the present invention
Is used in an amount of 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of the total amount of components (a) to (c).

Specific examples of the photopolymerization initiator (e) include benzophenone, benzoin isobutyl ether, benzoin isopropyl ether, benzyl dimethyl ketal, 2,2-diethoxyacetophenone, 2,2-dibutoxyacetophenone and 1-hydroxycyclohexyl. Phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-methyl-1- [4-
(Methylthio) phenyl] -2-morpholino-propanone-1,2-benzyl-2-dimethylamino-1-
(4-morpholinophenyl) -butanone-1, methylphenylglyoxylate, ethylphenylglyoxylate, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxane, 2,4,6- Examples thereof include trimethylbenzoyl diphenoyl phosphine oxide. These photopolymerization initiators can be used alone or as a mixture of two or more kinds.

Further, the curable coating material composition of the present invention contains a slip agent, an antifoaming agent, an anti-repellent agent, a wetting agent, an anti-settling agent, an anti-sagging agent, an ultraviolet absorber, an antioxidant, if necessary. Various additives such as a polymerization inhibitor and a coupling agent, and a volatile organic solvent for adjusting the viscosity can be mixed and used.

The curable coating material composition of the present invention can be produced simply by mixing the above-mentioned components. Further, when coating the substrate, spray coating, curtain flow coating, roll coating, dipping coating, spin coating, gravure coating, screen coating and the like can be applied and are not particularly limited.

The curable coating material composition of the present invention comprises a base such as an inorganic substance (iron plate, tin plate, galvanized sheet, aluminum plate, zinc steel plate, etc.) and organic substance (wood, paper, plastic, coating film of organic paint, etc.) and the like. It is used by applying it to a low pressure mercury lamp,
It can be rapidly cured by irradiation with ultraviolet rays such as a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a gallium lamp, a metal halide lamp, and sunlight. Further, the curable coating material composition of the present invention can be widely used for surface treatment of electronic parts and mechanical parts, or for etching resists such as shadow masks, printed wiring boards and resist boards. Further, it can be used as other paints, molding materials or casting materials.

[0025]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. Parts and% are based on weight unless otherwise specified.

Synthesis Example 1 <Production Example of Acrylic Copolymer c-1> Solvesso # 10 was placed in a container equipped with a stirrer, a temperature controller and a condenser.
0 (aromatic petroleum derivative, manufactured by Esso Corporation) was charged in 53.3 parts. The temperature was raised to 120 ° C. with stirring, and then 2 parts of azobisisobutyronitrile and 2 parts of t-butylperoxyisopropyl carbonate were added to 100 parts of the following monomer mixture, and the mixture was added dropwise over 3 hours. Next, 0.1 part of azobisisobutyronitrile was added 4 times at intervals of 30 minutes. After further heating and stirring at 120 ° C. for 2 hours to increase the reaction rate, 13.3 parts of n-butyl acetate was added to terminate the reaction. Styrene 5 parts Methacrylic acid 20 parts n-Butyl methacrylate 20 parts t-Butyl methacrylate 8 parts 2-Ethylhexyl methacrylate 29 parts 2-Hydroxyethyl methacrylate 18 parts The resulting acrylic copolymer c-1 has a weight average molecular weight of 14,000. The acid value was 78 mgKOH / g and the glass transition temperature was 49 ° C.

Synthesis Example 2 <Production Example of Acrylic Copolymer c-2> Polymerization was performed in the same manner as in Synthesis Example 1 except that the following monomer mixture was used to obtain an acrylic copolymer c-2. It was Styrene 17 parts Methacrylic acid 20 parts n-Butyl methacrylate 20 parts Methyl methacrylate 15 parts 2-Ethylhexyl methacrylate 10 parts 2-Hydroxyethyl methacrylate 18 parts The obtained acrylic copolymer c-2 has a weight average molecular weight of 16000 and an acid value. Was 39 mgKOH / g, and the glass transition temperature was 61 ° C.

Examples 1 to 6 and Comparative Examples 1 to 7 Table 1 shows the acrylic copolymers c-1 and c-2 obtained in the above Synthesis Examples 1 and 2 and each compound shown in Table 1. The mixture was mixed at different ratios to obtain a curable coating material composition. Each of the obtained compositions was coated on a steel plate having a large number of degreased fine holes (diameter 0.2 mm) with a bar coater so as to have a dry film thickness of 10 μm, and after preliminary drying at 60 ° C. for 5 minutes, Ultraviolet rays were radiated through a predetermined mask to form a cured coating film, which was then alkali-developed.

The evaluation results of these curable coating material compositions are shown in Table 1. As is clear from Table 1, the curable coating material composition of the present invention was excellent in alkali solubility, sealing property, etching resistance, and smoothness.

[0030]

[Table 1] a-1: ester of butanediol (1 mol) and acrylic acid dimer (2 mol) a-2: ester of tripropylene glycol (1 mol) and acrylic acid dimer (2 mol) a-3 : Ester of pentaerythritol (1 mol) and acrylic acid dimer (3 mol) b-1: Aronix M-5400 (monohydroxyethyl phthalate phthalate, manufactured by Toagosei Co., Ltd.) b-2: Aronix M -5600 (Carboxypolycaprolactone monoacrylate, Toa Gosei Chemical Co., Ltd.)
D-1: Dia-Aid AD-9002 (acrylate type, manufactured by Mitsubishi Rayon Co., Ltd.) d-2: Megafac F177 (fluorine type, manufactured by Dainippon Ink and Chemicals, Inc.) e-1: Irgacure 184 (Ciba Geigy) E-2: Benzophenone Evaluation Method Alkali Solubility: The solubility of the coating film after 1 minute of immersion in a 5% NaOH solution at 70 ° C. is visually determined. Sealing property: The sealing condition of the hole is visually judged. Etching resistance: 70 ° C in etching solution (FeCl ₂ ).
After soaking for 10 minutes, the appearance is visually judged. Smoothness: visually determined. Evaluation criteria A: Good B: Somewhat good C: Somewhat insufficient D: Inadequate E: Quite insufficient

[0031]

The curable coating material composition of the present invention can be cured by ultraviolet rays, and the coating film obtained is excellent in alkali solubility, sealing property, etching resistance and smoothness. Yes, its industrial significance is extremely high.

Claims (1)

[Claims] 1. (a) Compounds 10 to 8 represented by the following formulas:
0 parts by weight, (B) 20 to 70 parts by weight of a compound having one carboxyl group and one (meth) acryloyloxy group in one molecule, (c) 0 to 20 parts by weight of an acrylic copolymer containing a carboxyl group, (D) 0 to 0.5 part by weight of a leveling agent, and (e) 0.1 to 10 parts by weight of a photopolymerization initiator,
(However, the total of the components (a) to (c) is 100 parts by weight).