JPH0132493B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composition used for forming patterns on printed circuit boards, nameplates, photosensitive printing plates, etc., particularly a composition suitable for curing by irradiation with ultraviolet rays and peeling off by alkali. It is related to.

In recent years, ultraviolet curable resins have begun to be used to form patterns in articles such as those described above. This resin has a different curing mechanism from conventionally used thermosetting resins, so there is no thermal deformation of the base material on which the pattern is applied, and it can be cured in a short time. This is because it has features such as being able to avoid solvent pollution. On the other hand, when removing the cured resin after pattern formation, conventionally the mainstream method was to use a solvent to remove it, but due to problems such as work environment contamination and solvent pollution, there has been a shift to a method in which the resin is removed using an aqueous alkaline solution. Under these circumstances, various UV-curable alkaline removable pattern forming compositions have been studied, but if rapid curing with UV rays is desired, removability with alkaline aqueous solutions is poor, and removability with alkaline aqueous solutions is poor. If an attempt is made to improve the properties, there is a contradiction in that the curability deteriorates, and these required performances have not yet been fully satisfied.

The inventors of the present invention have completed the present invention as a result of intensive research to solve the above-mentioned problems.

That is, the pattern forming composition of the present invention contains methyltetrahydrophthalic acid and at least 1 molecule in the molecule.
monomers containing at least one hydroxyl group and at least one methacroyl or acroyl group (hereinafter referred to as A
A monoester compound (that is, methyltetrahydrophthalic acid monoester having vinyl polymerizability, hereinafter abbreviated as monoester B) is used as a binder component for film formation.
This is a composition containing 10% by weight or more.

In order to solve the above-mentioned problems, the present inventors have focused on and studied the use of monoester B obtained from polycarboxylic acids and monomer A and similar substances thereof, and as a result, the present inventors have found that monoester B of the present invention was found to be particularly effective.

Examples of methyltetrahydrophthalic acid that is a raw material for monoester B used in the present invention include 3-methyltetrahydrophthalic acid, 3-methyltetrahydrophthalic anhydride, 4-methyltetrahydrophthalic acid, and 4-methyltetrahydrophthalic acid. Examples include anhydrous substances.

In addition, A, which is the other raw material for monoester B,
Examples of monomers include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)
Acrylate, neopentyl glycol mono(meth)acrylate, 1,4-butanediol mono(meth)acrylate, 1,3-butadiol mono(meth)acrylate, 1,6-hexanediol mono(meth)acrylate, etc. Mono(meth)acrylate, trimethylolpropane mono(meth)acrylate, trimethylolpropane di(meth)acrylate, pentaerythritol mono(meth)acrylate, alkyltriol or alkyltetraol mono(meth)acrylate, etc. Acrylate or di(meth)acrylate, polyethylene glycol mono(meth)
Acrylate, mono(meth)acrylate of polyether such as polypropylene glycol mono(meth)acrylate, (meth)acrylic acid adduct of phenyl glycidyl ether, (meth)acrylic acid adduct of bisphenol A type epoxy compound, bisphenol Epoxy-based (meth)acrylates such as (meth)acrylic acid adducts of F-type epoxy compounds (the above expressions such as "(meth)acrylate" mean "methacrylate or acrylate" or "methacrylic acid or acrylic acid") (The same applies hereinafter.) etc.

Monoester B used in the present invention is synthesized by reacting methyltetrahydrophthalic acid with monomer A in such a manner that 1 mole of the hydroxyl group of the above monomer becomes 1 mole of methyltetrahydrophthalic acid. Of course, one of the reactants may be used in excess if necessary. The synthesis of monoester B of the present invention is preferably carried out by a ring-opening addition reaction between methyltetrahydrophthalic anhydride and the hydroxyl group of monomer A. It may be synthesized by a dehydration esterification reaction with a group. When carrying out the ring-opening addition reaction between methyltetrahydrophthalic anhydride and the hydroxyl group of the A monomer, tertiary amines such as triethylamine, morpholine, tribenzylamine, pentamethyldiethylenetriamine, or their quaternary Ammonium salt etc. may be used. In addition, in order to prevent polymerization during the reaction,
Polymerization inhibitors are usually used. Examples of these include polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, t-butylhydroquinone, t-butylcatechol, benzoquinone, tolquinone, phenothiazine, and the like. The amount of these used is generally about 0.01 to 1% by weight of the reactants.

The reaction temperature in the ring-opening addition reaction between methyltetrahydrophthalic anhydride and the above monomers is usually 50℃~
The temperature is preferably 150°C, preferably in the range of 80°C to 110°C.

The progress of the reaction can be easily determined by the infrared absorption spectrum of the reactant acid anhydride, provided that methyltetrahydrophthalic anhydride is not used in excess. The reaction may be considered to be substantially complete when the infrared absorption spectrum peak of the reactant acid anhydride disappears.

In the composition of the present invention, in addition to at least one type of monoester B, various vinyl polymerizable monomers, olicomers, resins having carboxyl groups, etc. can be used in combination as a binder component for forming a pattern-forming film. . The above monomers include:
For example, hydroxyethyl (meth)acrylate,
Hydroxypropyl (meth)acrylate, (meth)acrylic acid alkyl ester, phenoxydiethyl (meth)acrylate, butoxyethyl (meth)acrylate, ethyl carbitol ester of (meth)acrylic acid, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, etc., but evaporation is small when printing or coating the composition of the present invention for pattern formation. is preferred, and therefore monomers having a boiling point of 150°C or higher are preferred. Examples of the oligomers include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, and neopentyl glycol di(meth)acrylate. ) acrylate, 1,6 hexanediol di(meth)
Acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, etc. are used.
If these monomers or oligomers are used in an amount of 40% by weight or more of the binder component for film formation, the peeling speed with an alkaline aqueous solution is undesirably reduced.

Examples of the resins having carboxyl groups include polyester resins having carboxyl groups, acrylic resins having carboxyl groups, and styrene resins.
Examples include maleic acid copolymer, rosin, maleated rosin, etc., but preferably a resin that has good compatibility with monoester B and dissolves alone in an alkaline aqueous solution, and 0 to 10% of the binder component for film formation. It is preferable to use within the range of 40% by weight from the viewpoint of peeling speed under an alkaline aqueous solution.

The amount of monoester B in the pattern-forming composition of the present invention is desirably 10% by weight or more, preferably 30% by weight or more of the film-forming binder component. Ten
If the amount is less than % by weight, good results cannot be obtained in terms of removability with an aqueous alkaline solution and curability with ultraviolet light.

A photosensitizer is added to the composition of the present invention so as to form a cured coating film upon irradiation with ultraviolet rays. Examples of the photosensitizer include benzophenone derivatives such as benzophenone and p-chlorobenzophenone; benzoin derivatives such as benzoin, benzoin ethyl ether, benzoin propyl ether, and benzoin butyl ether; anthraquinone derivatives such as ethyl anthraquinone, chloranthraquinone, and amyl anthraquinone; Examples include acetophenone derivatives such as diethoxyacetophenone and dihydroxyacetophenone, thioxanthone derivatives such as chlorothioxanthone, and benzyl ketal derivatives, but they have good radical generation efficiency with ultraviolet rays, and when added to the composition of the present invention, dark It is preferable to use a photosensitizer that has good storage stability. The amount of the photosensitizer added is 0.1 to 10% by weight, preferably 0.5 to 5% by weight, based on the binder component for film formation.

In order to improve the printability and coating suitability when the composition of the present invention is printed or applied for pattern formation, the composition of the present invention may contain extender pigments, leveling agents, etc.
Antifoaming agents, coloring pigments, thixotropic agents, etc. may be added.

In practical use of the composition of the present invention, it is possible to obtain a pattern formed using the composition and cured by ultraviolet rays, and further, if necessary, this pattern can be removed with an alkali. After a desired pattern is printed on the surface of a metal such as aluminum or the like by a method such as screen printing or offset printing, a hardened film is formed by irradiation with ultraviolet rays. For UV irradiation, a lamp such as a high-pressure mercury lamp or a metal halide lamp with a power output of 50 to 200 W/cm is usually used, and photocuring can be completed within a short time of 30 seconds. Next, the exposed metal parts are etched with a metal etching agent such as ferric chloride, cupric chloride, or mineral acid, and then the cured film of the composition of the present invention is cured with an alkaline aqueous solution to form a metal pattern. manifest. Or,
After plating metals such as solder, gold, rhodium, etc. that are not affected by the above-mentioned etching liquid using an acidic or neutral plating liquid on the exposed metal parts, and removing the cured film of the composition of the present invention with an alkaline aqueous solution. It is also possible to use the above-mentioned etching agent to etch away the unplated metal surface of copper, aluminum, aluminum, etc. that is under the hardened film, and form a metal pattern using metal plating. It is possible.

The present invention will be explained below with reference to Examples and Comparative Examples. Parts and percentages in the examples are by weight unless otherwise specified.

Example 1 166 parts of 3-methyltetrahydrophthalic anhydride,
116 parts of hydroxyethyl acrylate (equimolar to the above acid anhydride) and 0.3 part of hydroquinone were placed in a flask equipped with a stirrer and reacted at 95°C. The reaction was carried out for 7 hours until the peak of the acid anhydride in the infrared absorption spectrum disappeared, and monoester B was obtained, which was used as a binder component for film formation. For 100 parts of the binder component for film formation, 5 parts of benzoin ethyl ether as a photosensitizer, 20 parts of barium sulfate as an extender to give screen printing suitability, 20 parts of talc, and a fine amount of silica as a thixotropy imparting agent. powder
0.5 parts, phthalocyanine blue as a coloring pigment
A pattern forming composition was prepared by adding 0.5 part.
This pattern-forming composition was printed with a film thickness of 20 μm on paper and copper foil attached to a phenolic resin laminate by screen printing, and was cured with ultraviolet light using a high-pressure mercury lamp of 80 W/cm. The time required for curing is 5
The hardness of the cured film was 2H.
Further, the exposed metal portion was removed by etching with a cupric chloride etching solution, and then the cured film was peeled off by immersing it in a 3% caustic soda aqueous solution at 40°C. The time required for peeling was 2 seconds.

Example 2 A binder component for film formation was prepared from 70 parts of monoester B obtained in Example 1 and 30 parts of dipropylene glycol diacrylate, and the following Example 1 was prepared.
A pattern forming composition was prepared in the same manner as above.

This pattern-forming composition was printed and cured in the same manner as in Example 1. The time required for curing was 4 seconds, and the pencil hardness of the cured film was 3H. Thereafter, etching was performed in the same manner as in Example 1 to peel off the cured film. The time required for peeling was 3 seconds.

Example 3 40 parts of maleic anhydride, 60 parts of phthalic anhydride, 40 parts of trimellitic anhydride, and 60 parts of ethylene glycol were placed in a flask equipped with a stirrer and a dehydration condensation reaction was carried out at 170°C, resulting in an acid value of 120 in 6 hours. A polyester resin having a carboxy group of A film-forming binder component was prepared from 20 parts of this polyester resin, 50 parts of ester B obtained in Example 1, and 30 parts of dicyclopentenyloxyethyl acrylate, and a pattern-forming composition was prepared in the same manner as in Example 1. did. This pattern-forming composition was printed and cured in the same manner as in Example 1. The time required for curing was 4 seconds, and the pencil hardness of the cured film was 4H. Thereafter, etching was performed in the same manner as in Example 1, and the cured film was peeled off. The time required for peeling was 4 seconds.

Example 4 A binder component for film formation was prepared from 50 parts of the monoester B obtained in Example 1, 20 parts of a styrene-maleic acid copolymer with an acid value of 300 and a molecular weight of 1500, and 30 parts of tetraethylene glycol diacrylate. Thereafter, a pattern forming composition was prepared in the same manner as in Example 1.

This pattern-forming composition was printed and cured in the same manner as in Example 1. The time required for curing was 4 seconds, and the pencil hardness of the cured film was 5H. Thereafter, etching was performed in the same manner as in Example 1, and the cured film was peeled off. The time required for peeling was 5 seconds.

Comparative Example 1 A film-forming binder component was prepared from 60 parts of the polyester resin having a carboxyl group obtained in Example 3 and 40 parts of dicyclopentenyloxyethyl acrylate, and a pattern-forming composition was prepared in the same manner as in Example 1. was created. This pattern-forming composition was printed and cured in the same manner as in Example 1.

The time required for curing was 20 seconds, and the pencil hardness of the cured film was 2B. Thereafter, etching was performed in the same manner as in Example 1 to peel off the cured film. The time required for peeling was 7 seconds.

Comparative Example 2 A film-forming binder component was prepared from 40 parts of a styrene-maleic acid copolymer with an acid value of 300 and a molecular weight of 1500 and 60 parts of tetraethylene glycol diacrylate, and a pattern-forming composition was prepared in the same manner as in Example 1. Created.

This pattern-forming composition was printed and cured in the same manner as in Example 1. The time required for curing was 4 seconds, and the pencil hardness of the cured film was 2H. Thereafter, etching was performed in the same manner as in Example 1, and the cured film was peeled off. The time required for peeling was 74 seconds.

Comparative Example 3 152 parts of tetrahydrophthalic anhydride, 116 parts of hydroxyethyl acrylate (equimolar to the above acid), and 0.2 parts of hydroquinone were placed in a flask equipped with a stirrer.
The reaction was carried out at 95°C. The reaction was continued for 7 hours until the peak of the acid anhydride in the infrared absorption spectrum disappeared to obtain a vinyl polymerizable phthalic acid monoester compound. A pattern-forming composition was prepared in the same manner as in Example 1 using this vinyl polymerizable tetrahydrophthalic acid monoester compound as a binder component for forming a film. This pattern-forming composition was printed simultaneously with Example 1 and cured. The time required for curing was 90 seconds, and the pencil hardness of the cured film was HB. Thereafter, etching was performed in the same manner as in Example 1 to peel off the cured film. The time required for peeling was 10 seconds.

Example 5 332 parts of 3-methyltetrahydrophthalic anhydride,
188 parts of trimethylolpropane monoacrylate,
0.5 part of hydroquinone (1 mole per 2 moles of the above anhydride) was placed in a flask equipped with a stirrer and reacted at 100°C. Monoester B was obtained by reacting for 10 hours until the infrared absorption spectrum disappeared. A film-forming binder component was prepared from 70 parts of this monoester B and 30 parts of dipropylene glycol diacrylate, and a pattern-forming composition was prepared in the same manner as in Example 1.

This pattern-forming composition was printed and cured in the same manner as in Example 1. The time required for curing is 4
The hardness of the cured film was 2H.
Thereafter, etching was performed in the same manner as in Example 1 to peel off the cured film. The time required for peeling was 2 seconds.

Claims (1)

[Claims] 1 Contains a monoester compound of methyltetrahydrophthalic acid and a monomer containing at least one hydroxyl group and at least one methacroyl or acroyl group in the molecule in an amount of 10% or more by weight of the film-forming binder component. A composition for forming a pattern.