JPS6329883B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polymer sensitizer that provides a photoinsolubilizable resin composition having excellent photosensitivity and a method for producing the same. More specifically, the present invention relates to a visible light-sensitizing polymer having a merocyanine residue conjugated with a dialkylaminophenyl group in its side chain as a photosensitizing residue, and a method for producing the same.

Many studies have been conducted to increase the photosensitivity of photoinsolubilizable resins based on the principle of photopolymerization.
Most of these concerns photopolymerization sensitizers (initiators) that are active in ultraviolet light. On the other hand, photosensitive resins are attracting attention not only as photoresist materials, inks, paints, varnishes, and printing plate materials, but also as image-forming materials that use laser light and photosensitive materials that replace silver salts. The photosensitivity of conventional materials is extremely inadequate. Therefore, it is necessary to expand the photosensitive wavelength range and dramatically increase the photosensitive speed. In this case, it goes without saying that the photosensitive resin must have both high resolution, which is an excellent property, and various physical properties suitable for the purpose.

Several proposals have been made for photopolymerizable resins that are sensitive to visible light. JP-A-48-36281 proposes a method in which S-triazine having at least one trihalomethyl group conjugated to a triazine ring due to ethylenically unsaturation and at least one chromophore moiety is used as a polymerization initiator. JP-A-54-155292 proposes a composition using an unsaturated ketone conjugated with p-dialkylaminoallylidene as a photopolymerization initiator. Further, in JP-A-52-134692, a composition using a polycyclic quinone and a tertiary amine as a photopolymerization initiation system is proposed.

All of these can provide materials that are sensitive to longer wavelength light than conventional photopolymerizable resins, but they require even higher sensitivity in order to be used as photosensitive materials for lasers or silver salt substitute materials. is necessary.

The photosensitivity of a photoinsolubilized resin depends on the molecular weight of the polymer to be insolubilized, the efficiency of the crosslinking reaction necessary for photoinsolubilization,
and the absorbance of the photosensitive group. The polymer composition that is sensitive to visible light is characterized by containing a low-molecular-weight photopolymerization initiator that absorbs visible light, so it is highly sensitive by focusing on the absorbance of the photosensitive group. I can say that.

As a result of careful consideration of the above points, the inventors of the present invention have found that by polymerizing the photopolymerization initiator that absorbs visible light, it is possible to achieve even higher sensitivity. The present invention was developed based on the idea that improved resolution could also be expected.

That is, the present invention provides the general formula () (In the formula, X is a simple bond, S or CH
=CH, Y represents N or CH=CH substituted with an alkyl group, Z represents a simple bond, -
OCOCH ₂ − or OCOCH ₂ CH ₂ ) and the photosensitizing structural unit (A) represented by the general formula () (In the formula, R ₁ represents at least one residue selected from an alkyl group, a phenyl group, a vinyl group, an isopropenyl group, and a 2-alkylvinyl group.) () (In the formula, R ₂ represents a C ₁ - C ₈ alkyl group) It is characterized by consisting of a vinyl structural unit (C) represented by 1~
30, 0~70, 99~0 mol%, molecular weight is 1000~
1,000,000 and a method for producing the same.

In the process of conducting research to develop a resin that is sensitive to long-wavelength light that extends into the near-infrared, the present inventors discovered that the combination of merocyanine and diaryliodonium salt can be an efficient photopolymerization initiation system. I found it. Generally, radical photopolymerization systems are significantly affected by oxygen in the air, and this photopolymerization initiation system is no exception. However, when using the photosensitizing polymer of the present invention having merocyanine in its side chain,
It has also been found that it exhibits the distinct advantage of retaining very high sensitivity even in the presence of oxygen.

In order to produce the polymer sensitizer of the present invention having these features, it is necessary to efficiently polymerize this relatively large molecular weight residue. The present invention also provides such a method. Below, a method for producing a photosensitizing polymer having a photosensitizing structural unit represented by the general formula () will be explained.

In order to obtain the photosensitized polymer of the present invention, a polymer of chloromethylstyrene or a copolymer thereof,
General formula () (In the formula, X, Y, and Z have the same meanings as above, and M
represents an alkali metal ion or a tetraalkylammonium ion). Furthermore, if desired, a carboxylic acid salt represented by the general formula () MOCOR ₁ ...() (wherein M and R ₁ have the same meanings as above) may be reacted.
In particular, by reacting the carboxylate represented by the general formula (), the physical properties of the resulting photosensitized polymer can be adjusted, and the storage stability of the polymer can be improved by consuming active chloromethyl groups. can be significantly increased. Alternatively, if an unsaturated carboxylic acid salt is used, a highly sensitive photo-insolubilizable resin composition can be provided since the unsaturated carboxylic acid salt itself will be involved in photopolymerization.

Examples of the merocyanine derivatives represented by the general formula () used here include alkali metal salts such as lithium, sodium, and potassium of the following compounds, and ammonium ions such as tetramethylammonium, tetraethylammonium, and triethylbenzylammonium. can.

In addition, carboxylic acid salts represented by the general formula () include acetic acid, propionic acid, butyric acid, valeric acid,
Alkyl carboxylic acids such as hexanoic acid, 2-ethylhexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, and decanoic acid; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, α-methylcrotonic acid, and 2-hexenoic acid. Preferred are acid or alkali metal salts such as lithium, sodium, and potassium such as benzoic acid, and ammonium salts such as tetramethylammonium, tetraethylammonium, and triethylbenzylammonium.

As the vinyl polymeric polymer containing at least 1 mol % of chloromethylstyrene used in the method for producing a photosensitized polymer in the present invention, a polymer of chloromethylstyrene or a copolymer thereof is preferable. The comonomer in the copolymer is
Acrylonitrile, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, tetrahydrofurfuryl acrylate, methyl methacrylate,
Ethyl methacrylate, butyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, N,N-dimethylacrylamide, N,N
-dimethylmethacrylamide, N-vinylpyrrolidone, styrene, etc. It goes without saying that these monomers can be used alone or in combination.

In order to react the merocyanine derivative represented by the general formula () and the carboxylic acid salt represented by the general formula () with a chloromethylstyrene polymer or copolymer, it is preferable to carry out the reaction in a polar solvent. Preferred polar solvents include dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, and dichlorobenzene.

The reaction temperature is preferably between room temperature and 120°C. If it is less than this, the reaction time will increase significantly, and if it is more than this, gelation may occur during the reaction. The reaction time is about 1 to 20 hours, depending on the reaction temperature and the reactivity of the halogen-containing polymer.

Furthermore, in this method, an alkali salt of the compound represented by the general formula () may be reacted with a halogen-containing polymer compound in an organic solvent using a crown ether, or an organic ammonium salt, phosphonium salt, etc. The reaction may be carried out in a two-phase system with an organic solvent using a phase transfer catalyst.

Since the compound represented by the general formula () has an amino group, there is a possibility that quaternization may occur due to the active chlorine group, but in reality, this amino group has a reduced reactivity due to the conjugated ketone via the double bond. Therefore, quaternization is unlikely to occur. In order to reliably prevent the product from gelling due to quaternization, the sum of the compounds represented by the general formula () and the general formula () should be equal to or 5 times the molar amount relative to the chloromethyl group. Just prepare it so that it will work.

The polymer having a photosensitizing residue in its side chain obtained by the present invention cannot be made insolubilized by light irradiation alone, but it can coexist with a compound that transfers one electron and generates a radical species by light irradiation. This results in a highly efficient photopolymerization initiation system. The electron-reduced compounds used for this purpose are electron-accepting, examples being ketones or quinones such as benzophenone, benzoquinone, naphthoquinone, atraquinone, benzanthrone, fluorenone, diphenyliodonium salts, ditolyl. Iodonium salts such as iodonium salts and di(m-nitrophenyl)iodonium salts,
2,4,6-tris(trichloromethyl)-S-
Triazine, 2-methyl-4,6-bis(trichloromethyl)-S-triazine, 2-phenyl-
S-triazine derivatives such as 4,6-bis(trichloromethyl)-S-triazine, P-nitro-
α,α,α-tribromoacetophenone, 0-nitro-α,α,α-tribromoacetophenone,
Trihaloacetylated benzene derivatives such as α,α,α-tribromoacetophenone, benzene derivatives with trihalomethanesulfonyl groups such as tribromomethanesulfonylbenzene, 1-tribromomethanesulfonyl-3-nitrobenzene, triphenylbisimidazolyl, etc. Among these, iodonium salts and triazine derivatives are particularly effective.

These electron-accepting compounds are used in an amount of 0.5 to 10 molar equivalents to the photosensitive residue represented by the general formula (),
More preferably, by mixing 1 to 5 molar equivalents, a highly efficient photopolymerization initiation system can be obtained.

Examples of the compound having at least one ethylenically unsaturated bond having polymerizability as the third component constituting the photoinsoluble resin composition containing the polymer sensitizer of the present invention include vinyl-based It may contain oligomers in addition to monomers, and may also be high molecular weight compounds. Specifically, there are high boiling point monomers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, acrylamide, methacrylamide, diacetone acrylamide, and N-vinylcarbazole, as well as ethylene glycol, diethylene glycol, and triethylene. Glycol, tetraethylene glycol, 1, 3
-propanediol, 1,4-butanediol,
Di- or polyacrylic esters such as 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, trimethylolethane, pentaerythritol, sorbitol, mannitol, di- or polymethacrylic esters, and even di- or polymethacrylic esters. Examples include acrylated or methacrylated epoxy resins, polyester acrylate oligomers, acrylated or methacrylated urethane oligomers, and acroleinated polyvinyl alcohol.

The amount of these polymerizable compounds is preferably 0.1 to 5 parts per 1 part of the polymer sensitizer of the present invention. It goes without saying that these polymerizable compounds need not be used alone, but may be a mixture of two or more.

The photoinsoluble resin composition comprising the polymer sensitizer of the present invention becomes insolubilized at a very high rate against light of a wavelength that is absorbed by the photosensitive group represented by the general formula (). This is because this photosensitive group absorbs light energy and transfers electrons to the electron-accepting compound, and the resulting cation radicals are desorbed from protons, and the radicals thus generated start polymerization, resulting in graft polymerization. It is thought that this is to cause Furthermore, the fact that the electron-accepting compound itself generates a radical after transferring one electron and becomes an initiator is considered to be one reason why the resin composition comprising the polymer sensitizer of the present invention exhibits high sensitivity.

Light sources suitable for the polymer sensitizer of the present invention include:
In addition to high-pressure mercury lamps, ultra-high-pressure mercury lamps, high-pressure xenon lamps, halogen lamps, and fluorescent lamps, He-Cd lasers and
Ar lasers can be used, but He-Ne lasers are particularly suitable.

Since the insolubilizing resin composition comprising the polymer sensitizer of the present invention has superior characteristics in sensitivity and resolution than conventional photopolymerizable compositions, it can It can be applied to a wide range of fields such as creating non-silver halide images and making printed wiring boards, and is also effective for negativeless plate making because it is sensitive to laser light. Furthermore,
It can also be used as an element material for photoelectric conversion.

Below, the present invention will be explained in more detail with reference to Examples.

Example 1 2-thioxo-
42.85 g of 5-[(3-methyl-2(3H)-benzothiazolylidene)-ethylidene]thiazolidinone was added and reacted under reflux for 30 minutes, and the precipitated crystals were filtered and dried to obtain a potassium salt. .

1:1 copolymer of chloromethylstyrene and methyl methacrylate (Mw=32.2×10 ⁴ , Mn=7.5×
After dissolving 1.26 g of 10 ⁴ ) in 20 g of dimethylformamide, 0.53 g of potassium methacrylate was added with stirring at 75°C, and the mixture was reacted for 2 hours. Then,
A solution of 0.35 g of the above potassium salt dissolved in 3 g of dimethylformamide was added and reacted for 3 hours.
The reaction solution was poured into a methanol-water mixture to separate the red polymer. After thoroughly washing with methanol, it was dissolved in tetrahydrofuran and filtered under pressure to obtain a purified polymer solution. 10% by weight polymer solution 1
Add 10 mg of diphenyliodonium salt to g,
When this was spin-coated on an anodized aluminum plate and the sensitivity was measured using a xenon lamp as a light source, it was found that polyvinyl cinnamate photosensitive material manufactured by Tokyo Ohka Kogyo Co., Ltd.
It showed approximately 64 times the sensitivity of TPR. Under degassed vacuum, it became about 128 times. Also, 488mm of argon laser
When exposure was carried out with light of
It was J/ ^cm2 .

Example 2 5:95 copolymer of chloromethylstyrene and methyl methacrylate (Mw=61.5×10 ⁴ , Mn=18.2
×10 ⁴ ) 1.5 g was dissolved in 20 g of dimethylformamide. A solution of 0.40 g of the potassium salt of thiazolidinone obtained in Example 1 dissolved in 3 g of dimethylformamide was added to this, and the mixture was reacted at 75° C. for 2 hours.
Then the tetramethylammonium salt of acetic acid 0.4
g and stirred for 2 hours. The reaction solution was poured into water-containing methanol to precipitate the polymer, which was again dissolved in dioxane and reprecipitated into methanol to obtain a red polymer. A solution of this polymer in tetrahydrofuran was prepared, and an equal amount of pentaerythritol triacrylate and 5
% by weight of diphenyliodonium salt was added to form a solution of the photosensitive composition. This composition was approximately 8 times more sensitive to TPR.

Example 3 2-thioxo-3-(2-carboxyethyl)-
5-[(Ethyl-4(1H)-quinolylidene)-ethylidene]thiazoline-4 was converted into a potassium salt in the same manner as in the examples. 1.0 g of the 5:95 copolymer of chloromethylstyrene and methyl methacrylate used in Example 2 (Mw = 61.5 x 10 ⁴ , Mn = 18.2 x 10 ⁴ ) was dissolved in 15 g of dimethylformamide, and a potassium salt was added thereto. A solution of 0.3g dissolved in 3g of dimethylformamide was added and stirred at 75°C for 1 hour, then 0.2g of tetramethylammonium acetate was added and stirred for 2 hours. The reaction solution was poured into aqueous methanol to separate the blue polymer. After washing thoroughly with water-containing methanol and methanol, make a dioxane solution.
The same amount of pentaerythritol triacrylate as the polymer and 10% by weight of diphenyliodonium.
Hexafluorophosphate was added to determine the sensitivity of this composition. It showed approximately 8 times the sensitivity of TPR.

Claims (1)

[Claims] 1. General formula (In the formula, X is a simple bond, S or CH
=CH, Y represents N or CH=CH substituted with an alkyl group, Z represents a simple bond, -
OCOCH ₂ − or −OCOCH ₂ CH ₂ ) and the photosensitizing structural unit (A) represented by the general formula (In the formula, R ₁ represents at least one residue selected from an alkyl group, a phenyl group, a vinyl group, an isopropenyl group, and a 2-alkylvinyl group.) formula (In the formula, R ₂ represents a C ₁ to C ₈ alkyl group.) 1 to 30 each,
Molecular weight is 0-70, 99-0 mol% is 1000-
Photosensitizing polymer compounds in the range of 1,000,000. 2 General formula A structural unit consisting of 1 to 100 mol% chloromethylstyrene represented by the general formula ( _R2 in the formula represents a _C1 - _C8 alkyl group) (In the formula, X is a simple bond, S or CH
=CH, Y represents N substituted with an alkyl group or CH=CH, M represents an alkali metal ion or tetraalkylammonium ion, Z represents a simple bond, -OCOCH ₂ - or -
merocyanine derivatives represented by the general formula MOCOR ₁ (wherein M has the same meaning as above, _{and R 1 is} an alkyl group, phenyl group _, vinyl group, A general formula characterized by reacting a carboxylic acid salt represented by (wherein, X, Y, and Z have the same meanings as above) and a photosensitizing structural unit (A) represented by the general formula (In the formula, R ₁ has the same meaning as above) and the structural unit (B) represented by the general formula (In the formula, R ₂ has the same meaning as above.) It is characterized by consisting of a vinyl structural unit (C) represented by ,
Molecular weight is 0-70, 99-0 mol% is 1000-
A method for producing photosensitizing polymer compounds in the range of 1,000,000.