JP2000336144A - Epoxy acrylate compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new epoxy acrylate compound which gives a cured product having a high glass transition temperature and a low water-absorbing property and thereby excellent in water resistance and heat resistance and is also useful as a component for photosensitive resin compositions used for solder resists, electronic part-protecting films, and so on. SOLUTION: A compound of the formula [R is H or methyl; (n) is a natural number, preferably a <=9 natural number]. The compound of the formula is obtained, for example, by reacting the epoxy groups of the corresponding biphenyl skeleton-having epoxy compound with the carboxyl group of acrylic acid or methacrylic acid in the presence of a catalyst usually at 50 to 150 deg.C for about 1 to 15 hr. The used catalyst includes amines such as triethylamine, quaternary ammonium salts such as tetramethylammonium salt, quaternary phosphonium salts, phosphines such as triphenyl phosphine, and imidazoles such as 2-methylimidazole. The compound of the formula may be compounded with a photopolymerization initiator, one or more photopolymerizable monomers, an organic solvent and so on to produce a photosensitive resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel epoxy acrylate compound. The epoxy acrylate compound of the present invention can obtain a polymer material having excellent water resistance and heat resistance by polymerizing the epoxy acrylate compound itself or by copolymerizing it with another unsaturated compound. Further, the epoxy acrylate compound of the present invention can be made into a photosensitive resin composition by combining with a photopolymerization initiator, and the photosensitive resin composition is used for producing a printed wiring board, a printed wiring board, and the like. Used for a wide range of applications such as resin for permanent resist such as solder resist resin and insulating resist for build-up substrate, resin for electroless plating resist, sealing resin for liquid crystal display panel, and color filter for liquid crystal be able to.

[0002]

2. Description of the Related Art Conventionally, epoxy acrylate compounds have
It is widely used as a raw material for various functional polymer materials such as photosensitive materials, optical materials, dental materials, and various polymer crosslinking agents. However, in recent years, with the advancement of required performance in these application fields, physical properties required as a functional polymer material have become increasingly severe. As such physical properties, for example, heat resistance, weather resistance, low water absorption, high refractive index, high fracture toughness, etc. are required, but to date, these required physical properties have not always been satisfied.

For example, in the manufacture of printed wiring boards,
It is known to be used for a photo solder resist used as a permanent mask. Such resist materials include novolak-type epoxy acrylate compounds as disclosed in JP-A-61-243869 and bisphenolfluorene-type epoxy acrylate compounds as disclosed in JP-A-3-205417. And acid-modified products of these epoxy acrylate compounds. Epoxy acrylate compounds used as resist materials are required to have heat resistance to solder bath immersion in printed wiring board applications. If the heat resistance is insufficient, the resist film will swell and peel off, resulting in defective products. Cause.

In recent years, the density of printed wiring boards has been increasing, and materials having higher heat resistance and higher reliability have been desired. However, conventional solder resists using epoxy acrylate compounds have high heat resistance. Was not enough. Therefore, a new epoxy acrylate compound satisfying the above requirements has been desired.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a novel epoxy acrylate compound and a photosensitive resin composition having excellent water resistance and heat resistance, which could not be achieved by the prior art. It is in.

[0006]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above-mentioned object, and as a result, completed the present invention. That is, the present invention is an epoxy acrylate compound having a biphenyl skeleton represented by the following general formula (1). In the general formula (1), n is 9 or less, more preferably 4 or less, and particularly preferably 1 or less. Are suitable.

[0007]

Embedded image (In the formula, R represents a hydrogen atom or a methyl group, and n represents a natural number.)

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy acrylate compound of the present invention can be synthesized according to a known method. That is, it can be obtained by reacting the epoxy group of the corresponding epoxy compound having a biphenyl skeleton with the carboxyl group of acrylic acid or methacrylic acid.
This reaction is usually performed at a temperature in the range of 50 to 150 ° C. for about 1 to 15 hours. Examples of the catalyst include amines such as triethylamine, dimethylbutylamine and tri-n-butylamine; quaternary salts such as tetramethylammonium salt, tetraethylammonium salt, tetrabutylammonium salt and benzyltriethylammonium salt; or quaternary salts. Phosphonium salts, other phosphines such as triphenylphosphine, 2-methylimidazole, 2-ethyl-
Imidazoles such as 4-methylimidazole;

In the reaction, alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve and ethyl cellosolve, esters such as methyl cellosolve acetate and ethyl cellosolve acetate, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. , Aromatic compounds such as benzene, toluene, chlorobenzene, and dichlorobenzene can be used as reaction solvents. In the reaction, hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, 4-methylquinoline, phenothiazine and the like may be coexisted in the reaction system as a polymerization inhibitor.
Furthermore, in order to suppress the polymerization reaction due to the unsaturated bond, the reaction can be carried out under a stream of air or the like in some cases. At that time, an antioxidant such as 2,6-di-t-butyl-4-methylphenol may be used in combination to prevent an oxidation reaction due to air.

The acid-modified epoxy acrylate compound of the present invention is produced by reacting the epoxy acrylate compound with a carboxylic acid or an acid anhydride thereof. Examples of the carboxylic acid or its acid anhydride include maleic acid, succinic acid, itaconic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydrophthalic acid, chlorendic acid, methylnadic Examples include acids, trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid, and the like, and acid anhydrides thereof, but are not limited thereto.

Further, a photopolymerization initiator and, if necessary, other photopolymerizable monomers and / or an organic solvent are blended with the epoxy acrylate compound of the present invention or the above-mentioned acid-modified epoxy acrylate compound. Thus, a photosensitive resin composition can be obtained.

Examples of the photopolymerization initiator include benzoins such as benzoin and benzoin methyl ether; acetophenones such as acetophenone and 1,1-dichloroacetophenone; anthraquinones such as anthraquinone and 2-methylanthraquinone; Thioxanthones such as dimethylthioxanthone and 2-chlorothioxanthone, ketals such as benzyldimethylketal, benzophenones such as benzophenone and bis (diethylamino) benzophenone, and the like, and these compounds and amines such as benzyldimethylamine and triethanolamine And a composite photopolymerization initiator. These can be used alone or in combination of two or more.

Examples of the photopolymerizable monomer include water-soluble monomers such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, N-vinylpyrrolidone, methoxypolyethylene glycol acrylate, N, N-dimethylacrylamide, methyl acrylate, and cyclohexyl. Water-insoluble monomers such as acrylate, cyclohexyl methacrylate, diethylene glycol diacrylate, polypropylene glycol diacrylate, and pentaerythritol triacrylate can be exemplified.

Examples of the organic solvent include ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene and xylene;
Examples include cellosolves such as methyl cellosolve and butyl cellosolve, and esters such as cellosolve acetate and butyl acetate.

The light source for curing the photosensitive resin composition is not particularly limited, but usually a xenon lamp, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp and the like are used.

[0016]

EXAMPLES Hereinafter, the present invention will be specifically described based on examples and comparative examples, but the present invention is not particularly limited by the following examples. In the examples, parts and%
Are by weight unless otherwise specified.

REFERENCE EXAMPLE 1 A 1 L (liter) four-necked flask equipped with a thermometer, a dropping funnel, a cooling tube, and a stirrer was placed under a nitrogen stream under 2,2 ',
135 parts of 3,5 ', 6,6'-hexamethylbiphenol, 925 parts of epichlorohydrin and 340 parts of dimethyl sulfoxide were added and dissolved therein. This solution was heated to 55 ° C., and 40 parts of flaky sodium hydroxide was added in portions over 100 minutes, followed by reaction at 55 ° C. for 2 hours and further at 70 ° C. for 30 minutes. After completion of the reaction, use a rotary evaporator,
After evaporating excess epichlorohydrin, dimethyl sulfoxide and the like under heating and reduced pressure at 130 ° C., 191 parts of methyl isobutyl ketone was added to dissolve the residue.

The solution of methyl isobutyl ketone obtained above was heated to 70 ° C., 10 parts of a 30% aqueous sodium hydroxide solution was added, and the mixture was reacted for 1 hour. After the reaction, washing of the reaction solution with pure water was repeated until the pH of the washing solution became neutral. The aqueous layer was separated by phase separation, and methyl isobutyl ketone was distilled off from the organic layer under reduced pressure by heating using a rotary evaporator to obtain 172 parts of an epoxy compound. The obtained epoxy compound is a crystal having a melting point of 115 ° C. and an epoxy equivalent of 191.
g / eq.

Reference Example 2 The procedure of Reference Example 1 was repeated except that epichlorohydrin was replaced by 370 parts and dimethylsulfoxide was replaced by 93 parts. 164 parts of epoxy resin crystals were obtained. This epoxy resin had a melting point of 110 ° C. and an epoxy equivalent of 209 g / eq.

Reference Example 3 The procedure of Reference Example 1 was repeated except that epichlorohydrin was replaced with 278 parts. 156 parts of epoxy resin crystals were obtained.
This epoxy resin has a melting point of 102 ° C and an epoxy equivalent of 273 g /
eq.

Example 1 172 parts of the epoxy compound obtained in Reference Example 1 and 65 of acrylic acid
Were dissolved at 60 ° C (epoxy compound: acrylic acid = 0.5: 1 molar ratio), 3.4 parts of triethylbenzyl chloride as a catalyst and 0.1 part of hydroquinone as a polymerization inhibitor were added, and the mixture was heated to 90 to 95 ° C. And reacted under stirring.
During the reaction, the acid value and epoxy equivalent were measured, and the acid value was 2.0 mgKOH
The reaction was carried out for 14 hours with the time at which the epoxy equivalent reached 15,000 g / eq or less and the epoxy equivalent reached 15,000 g / eq or more, and the target product was obtained in 98% yield. The obtained target substance was a viscous liquid at a temperature of 60 ° C.

The reaction product obtained above was subjected to 1H-NMR measurement (solvent: DMSO, internal standard substance: TMS), and the following results were obtained. [delta] (ppm) Number of protons attributable 1.8 6H -CH ₃ (3,5 _{'position) 2.2 12H -CH 3 (2,2'} , 6,6 ' position) 2.5 2H -OH 3.8 - 4.3 10H -OCH 2 CH-CH _{2 O- 6.0 2H -CH = C H} 2 6.2 2H -C H = CH 2 6.4 2H -CH = C H 2 6.7 2H aromatic hydrogen from the results, the reaction R is a hydrogen atom in the general formula (1), It was confirmed that n = 1.

Examples 2 and 3 The reaction was carried out in the same manner as in Example 1 except that the epoxy compound obtained in Reference Example 2 or 3 was used to obtain a target product. This target substance was a viscous liquid at 60 ° C. When the epoxy resin of Reference Example 2 or 3 was used, the spectrum obtained by 1H-NMR measurement was almost the same as that of Example 1, and the integral ratio of protons of the acrylic group was increased as the epoxy equivalent became larger.
(6.0, 6.2, 6.4 ppm) is smaller than the whole.

Comparative Examples 1 and 2 In Example 1, 162 parts of bisphenol A glycidyl ether (epoxy equivalent 180 g / eq) (Comparative Example 1) and tetramethylbiphenyl glycidyl ether (epoxy equivalent 180 g / eq) were used in place of the epoxy resin used in Reference Example 1. Epoxy equivalent 190g / eq) 171
A reaction product with acrylic acid was produced in the same manner as in Example 1 except that the part (Comparative Example 2) was used. The obtained reaction product was a viscous liquid at 60 ° C., and the yields were 97% and 98%, respectively.

Example 4 Epoxy acrylate compound obtained in the same manner as in Reference Example 1.
Add 170 parts of trimellitic anhydride to 172 parts, and at 90 ° C
The reaction was carried out for 20 hours to obtain 340 parts of an acid-modified epoxy acrylate.

Examples 5 to 8 and Comparative Examples 3 to 5 The epoxy acrylate compounds obtained in Examples 1 to 3 (Examples 5, 6, and 7) and Comparative Examples 1 and 2 (Comparative Examples 3 and 4) And the acid-modified epoxy acrylate compound obtained in Example 4 (Example 8), and KAYARAD R-5089 (reacted product of bisphenol A type epoxy acrylate and dibasic acid anhydride, manufactured by Nippon Kayaku Co., Ltd.) Example 5) was used in each of 50 parts, and each of them was denacal T (xylene novolak type epoxy resin,
Nagase Kasei) 15 parts, Irgacure 651 (photopolymerization initiator, Ciba Geigy) 5 parts, BYK 357 (antifoaming agent, Big Chemie) 1 part, phthalocyanine green (pigment,
1 part, 20 parts talc and barium sulfate
The components were mixed in a composition of 10 parts and kneaded with a three-roll mill (manufactured by Imex Co., Ltd.) to prepare a photosensitive resin composition. This photosensitive resin composition was evaluated by the following test methods, and the results are shown in Table 1.

(Production method of coating film) The photosensitive resin composition is applied to the entire surface of the copper-clad laminate by screen printing so that the film thickness after drying becomes 40 μm, and this is placed in a dryer at 70 ° C. After 30 minutes, it was confirmed that tackiness had disappeared, and an exposure pattern film was mounted on the film using a parallel exposure machine, and light was exposed at 250 mJ / cm ² . After exposure, development was performed with a 1% aqueous solution of sodium carbonate for 60 seconds at a spray pressure of 1.5 kg / cm ² . After washing with water, it was placed in a hot air drier at 160 ° C. for 1 hour to perform heat curing. The substrate having the obtained cured film was tested for glass transition temperature, water absorption, water resistance, and solder heat resistance in the manner described below.

(Evaluation Method of Photosensitive Resin Coated Substrate) Using the photosensitive resin coated substrate manufactured by the above method, characteristics were evaluated by the following test methods. (1). Glass transition temperature: The coating film was peeled off from the substrate, and JIS 6481
According to the test method described above, the measurement was performed by a TMA tensile test. (2). Water absorption: using a photosensitive resin-coated substrate having a cured film, dried at 50 ° C. for 24 hours, measured the weight (W1),
After absorbing water for 1 hour in a pressure cooker (121 ° C., 2 atm), the weight was measured again (W2), and the water absorption (%) was determined by (W2−W1) / W1 × 100.

(3) Water resistance: Using a photosensitive resin-coated substrate having a cured film, the appearance change of the cured film after boiling in boiling water at 100 ° C. for 1 hour or 2 hours was visually observed. ：: no change in appearance △: swelling is observed in a part of the cured film ×: swelling or peeling is observed in a considerable part of the cured film

(4) Solder heat resistance: Using a photosensitive resin-coated substrate having a cured film, the test piece was immersed in a 260 ° C. solder bath for 10 seconds for 10 times according to JIS C 6481, and the appearance was changed. Was visually observed. ：: no change in appearance △: swelling is observed in a part of the cured film ×: swelling or peeling is observed in a considerable part of the cured film

[0031]

[Table 1] Example Comparative Example 5 6 7 8 3 4 5 Glass transition temperature (° C) 142 140 132 145 105 130 110 Water absorption (%) 0.6 0.6 0.7 0.7 1.4 0.8 1.3 Water resistant boiling 1 hr ○ ○ ○ ○ × ○ × 2hrs ○ ○ ○ ○ × △ × 3hrs ○ ○ ○ ○ × × × Heat resistance of solder ○ ○ ○ ○ △ ○ △

[0032]

The epoxy acrylate compound of the present invention has a high glass transition temperature and low water absorption,
It is extremely excellent in water resistance and heat resistance, and when the epoxy acrylate compound and the acid-modified epoxy acrylate compound of the present invention are used as a photosensitive resin, application to a solder resist, a protective film for electronic parts, and the like can be expected.

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 4J027 AC03 AC04 AC06 AE01 AE02 AE04 AE07 AJ08 BA01 BA08 BA14 BA15 BA19 BA24 CA10 CB10 CC05 CD08 CD10 4J036 AA01 AD01 AD04 AD07 CA19 CA20 CA21 CA25 FA10 FA12 FB06 FB12 HA02 JA09

Claims (3)

[Claims] 1. An epoxy acrylate compound having a biphenyl skeleton represented by the following general formula (1). Embedded image (In the formula, R represents a hydrogen atom or a methyl group, and n represents a natural number.) 2. The epoxy acrylate compound according to claim 1, wherein n is 1 in the general formula (1). 3. An acid-modified epoxy acrylate compound obtained by reacting the epoxy acrylate compound according to claim 1 with a carboxylic acid or a carboxylic anhydride.