JPH08129258A - Photopolymerizable composition - Google Patents

Abstract

PURPOSE: To ensure high sensitivity and superior shelf stability by adding specified dialkylaminobenzoic esters to a high sensitivity photopolymn. initiating system prepd. by combining a titanocene compd. with a specified coumarin compd. CONSTITUTION: A titanocene compd., at least one kind of coumarin compd. represented by formula I and at least one of compds. represented by formulae II-IV are incorporated into a photopolymn. initiating system. In the formula I, each of R<1> , R<2> and R<5> is H, halogen, alkyl or alkoxy, each of R<3> and R<4> is alkyl, at least one of pairs R<2> -R<3> and R<4> -R<5> or R<3> and R<4> may form optionally substd. alkylene by combination with each other, R<6> is H, alkyl, acyl, cyano, carboxyl, its ester deriv., etc., and R<7> is a 3-17C residue of a hetero ring. In the formulae II-IV, each of R<8> -R<18> is alkyl.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photopolymerizable composition. In particular, the present invention relates to a photopolymerizable composition having high sensitivity to light in the visible region and excellent in storage stability.

[0002]

2. Description of the Related Art Conventionally, many image forming methods utilizing a photopolymerization system are known. For example, a photopolymerizable composition comprising a compound containing an addition-polymerizable ethylenic double bond, a photopolymerization initiator, and an organic polymer binder optionally used is prepared, and the photopolymerizable composition is supported. A photosensitive material having a layer of a photopolymerizable composition applied on the body is prepared, and a desired image is imagewise exposed to polymerize and cure the exposed portion, and the unexposed portion is dissolved and removed to form a cured relief image. And a layer of the photopolymerizable composition is provided between two supports in which at least one of the above-mentioned photosensitive materials is transparent, and the transparent support side is imagewise exposed to cause a change in adhesive strength by light. After that, there is a method of forming an image by peeling the support, and an image forming method utilizing the change of toner adhesion of the photopolymerizable composition layer due to light. Conventionally, benzoin, benzoin alkyl ether, benzyl ketal, benzophenone, anthraquinone, benzyl, or Michler's ketone has been used as the photopolymerization initiator of the photopolymerizable composition applied to these methods.

However, these photopolymerization initiators are
Compared with the ability to initiate photopolymerization for light in the ultraviolet region below 00 nm, it is significantly lower than that for light in the visible light region above 400 nm, thus limiting the range of application of photopolymerizable compositions containing them. In recent years, with the development of image forming technology, there has been a strong demand for photopolymers having high sensitivity to light rays in the visible region. It is a photosensitive material suitable for, for example, non-contact type projection exposure plate making or laser plate making using a visible light laser. Among these technologies, especially the 488 of argon ion laser
The plate-making method using an oscillation beam of nm is considered to be one of the most promising techniques in the future.

Several proposals have hitherto been made for photopolymerization compositions containing a photopolymerization initiation system capable of being sensitive to light rays in the visible light region. For example, a system of hexaarylbiimidazole and (p-dialkylaminobenzylidene) ketone (JP-A-47-2528, JP-A-54-155)
No. 292, JP-A-56-166154), a system of ketocoumarin and an activator (JP-A-52-112681,
JP-A-58-15503 and JP-A-60-88005), and a system of a substituted triazine and a sensitizer (JP-A-54-15803).
151024, JP-A-58-29803, JP-A-5-
Nos. 8-40302), a system of biimidazole, a styrene derivative, and a thiol (JP-A-59-56403), and a system of an organic peroxide and a dye (JP-A-59-1402).
03, JP-A-59-189340)
A system of a titanocene compound and a sensitizer (JP-A-63-2211).
No. 10, JP-A-4-26154, JP-A-4-2197
No. 56). Although these are certainly effective to some extent, the sensitivity is not sufficient from a practical point of view, and an improved technique has been desired.

As a visible sensitization system using a titanocene compound, for example, a combination system with a coumarin compound having a specific structure having a heterocyclic ring has been proposed, and a certain level of effect is expected (Japanese Patent Laid-Open No. Hei 3). No. 239703, JP-A-5-289335).

[0006]

However, even in the case of this system, for example, in the case of being applied to laser plate making, it has some problems, namely, a system having higher sensitivity and good storage stability. Was required.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a high sensitivity photopolymerization initiation system combining a titanocene compound and a coumarin compound having a specific skeleton has a specific skeleton. By adding a dialkylaminobenzoic acid ester having a high sensitivity to visible light, especially light of 488 nm, and excellent in safelight property and storage stability over time, photopolymerizability suitable for laser plate making The inventors have found that the composition is a composition and arrived at the present invention.

That is, the first object of the present invention is to provide a photopolymerizable composition having sufficient sensitivity, and the second object is to provide a photopolymerizable composition excellent in storage stability. Yet another object is to provide a photopolymerizable composition having excellent sensitivity especially at 488 nm and suitable for laser plate making. The object of the present invention is to provide a photopolymerizable composition containing a compound having at least one addition-polymerizable ethylenically unsaturated double bond and a photopolymerization initiation system, wherein the photopolymerization initiation system is (a) titanocene. Compound,
(B) At least one coumarin compound represented by the following general formula [I]

[0009]

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[Wherein R ¹ , R ² and R ⁵ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and R ³ and R ⁴ each represent an alkyl group, provided that R ³ and R 5 ² and at least one set of R ⁴ and R ⁵ or R ³ and R ⁴ may be linked to each other to form a substituted or unsubstituted alkylene group, and R ⁶ is a hydrogen atom, an alkyl group or an acyl group. Represents a cyano group, a carboxyl group or an ester derivative or an amide derivative thereof; R ⁷ represents a heterocyclic residue having a total of 3 to 17 carbon atoms. ], And (c) the following general formula [II],
At least one compound represented by [III] or [IV]

[0011]

[Chemical 4]

[In the formula, R ^{8 to} R ¹⁸ each represent an alkyl group. ] It is easily achieved by the photopolymerizable composition characterized by containing.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The compound having at least one addition-polymerizable ethylenically unsaturated double bond contained as the first essential component in the photopolymerizable composition of the present invention (hereinafter abbreviated as “ethylenic compound”) means photopolymerization. When the photosensitive composition is irradiated with actinic rays, it is a compound having an ethylenically unsaturated double bond that undergoes addition polymerization by the action of a photopolymerization initiation system that is a second essential component and is cured, for example, It is a monomer having the above double bond, or a polymer having an ethylenically unsaturated double bond in the side chain or main chain. Incidentally, the meaning of the monomer in the present invention is a concept facing a so-called polymer substance, and therefore includes not only a narrowly defined monomer but also a dimer, a trimer and an oligomer. is there.

Examples of the monomer having an ethylenically unsaturated bond include unsaturated carboxylic acid, ester of aliphatic polyhydroxy compound and unsaturated carboxylic acid; ester of aromatic polyhydroxy compound and unsaturated carboxylic acid; Examples thereof include esters obtained by an esterification reaction of a saturated carboxylic acid with a polyvalent carboxylic acid and the above-mentioned aliphatic polyhydroxy compound, polyvalent hydroxy compound such as aromatic polyhydroxy compound, and the like.

The ester of the aliphatic polyhydroxy compound and the unsaturated carboxylic acid is not limited, but specific examples thereof include ethylene glycol diacrylate, triethylene glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate. , Pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, acrylate ester of polyhydroxy compound such as glycerol acrylate, Methacrylic acid ester in which acrylate was replaced with methacrylate, similarly replaced with itaconate Itaconic acid esters, maleic acid esters in which instead of the crotonic acid ester or maleate was replaced crotonate.

Examples of the ester of an aromatic polyhydroxy compound and an unsaturated carboxylic acid include hydroquinone diacrylate, hydroquinone dimethacrylate, resorcin diacrylate, resorcin dimethacrylate and pyrogallol triacrylate. The ester obtained by the esterification reaction between the unsaturated carboxylic acid and the polyhydric carboxylic acid and the polyhydric hydroxy compound is not necessarily a single substance, but typical examples include acrylic acid, phthalic acid and ethylene glycol. Condensates, condensates of acrylic acid, maleic acid and diethylene glycol, condensates of methacrylic acid, terephthalic acid and pentaerythritol, condensates of acrylic acid, adipic acid, butanediol and glycerin, and the like.

In addition to the above ester (meth) acrylate, there are so-called urethane (meth) acrylate and epoxy (meth) acrylate. The former can be prepared by an addition reaction between a polyvalent isocyanate and hydroxyacrylic esters, and the latter can be prepared by an addition reaction between a polyvalent epoxy compound and hydroxyacrylic esters.

Other examples of the ethylenic compound used in the present invention include acrylamides such as ethylenebisacrylamide; allyl esters such as diallyl phthalate;
Vinyl group-containing compounds such as divinyl phthalate are useful. The polymer having an ethylenically unsaturated bond in the main chain is, for example, a polyester obtained by a polycondensation reaction between an unsaturated divalent carboxylic acid and a dihydroxy compound,
There is a polyamide obtained by a polycondensation reaction between an unsaturated divalent carboxylic acid and a diamine. Polymers having an ethylenically unsaturated bond in the side chain include condensation polymers of a divalent carboxylic acid having an unsaturated bond in the side chain such as itaconic acid, propylidene succinic acid, ethylidene malonic acid and a dihydroxy or diamine compound. . Further, a polymer having a functional group having a reactive activity such as a hydroxy group or a methyl halide group in its side chain, for example, polyvinyl alcohol, poly (2-hydroxyethyl methacrylate), polyepichlorohydrin, etc. and acrylic acid, methacrylic acid, crotonic acid, etc. Polymers obtained by the macromolecular reaction with the unsaturated carboxylic acid can also be suitably used.

Among the above-mentioned ethylenic compounds, the monomers of acrylic acid ester or methacrylic acid ester can be particularly preferably used, and among them, acrylic acid ester or methacrylic acid ester of aliphatic polyhydroxy compound is preferable. Next, the photopolymerization initiation system, which is the second essential component of the photopolymerization composition of the present invention, will be described. The photopolymerization initiation system of the present invention is composed of a combination of three kinds of components, and the first component thereof is a titanocene compound represented by (a) in the present invention. Although the titanocene compound is not particularly limited, for example, JP-A-59-152396,
It can be appropriately selected and used from various titanocene compounds described in JP-A-61-151197. More specifically, di-cyclopentadienyl-T
i-di-chloride, di-cyclopentadienyl-Ti
-Bis-phenyl, di-cyclopentadienyl-Ti-
Bis-2,3,4,5,6-pentafluorophenyl-1
-Yl, dicyclopentadienyl-Ti-bis-2,
3,5,6-Tetrafluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,4,6-trifluorophen-1-yl, di-cyclopentadienyl-
Ti-bis-2,6-di-fluorophen-1-yl,
Di-cyclopentadienyl-Ti-bis-2,4-di-
Fluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2,3,4,5,6-pentafluorophen-1-yl, di-methylcyclopentadienyl-Ti-bis-2 , 3,5,6-Tetrafluorophen-1-yl, di-methylcyclopentadienyl-Ti
-Bis-2,6-difluorophen-1-yl, di-cyclopentadienyl-Ti-bis-2,6-difluoro-3- (pyr-1-yl) -phen-1-yl (hereinafter,
Examples thereof include a titanium complex having a dicyclopentadienyl group such as A-1).

Next, the coumarin compound represented by the second component (b) of the photopolymerization initiation system of the present invention will be described. This compound is a coumarin compound represented by the above general formula [I] and having a heterocyclic residue at the 3-position. These compounds can be prepared according to a conventional method, for example, by a condensation reaction between an acetic acid ester having a heterocyclic residue and p-substituted aminosalicylaldehyde.

In the above formula [I], R ¹ , R ² and R ⁵ each represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group; R ³ and R ⁴ each represent an alkyl group, provided that R ^At least one set of ³ and R ² and R ⁴ and R ⁵ or R ³ and R ⁴ may be connected to each other to form a substituted or unsubstituted alkylene group, and R ⁶ is a hydrogen atom or an alkyl group. , An acyl group, a cyano group, a carboxyl group or an ester derivative or amide derivative thereof, and R ⁷ has a total number of carbon atoms of 3 to
Of the 17 heterocyclic residues, nitrogen-containing aromatic heterocyclic residues are preferable, and condensed ring nitrogen-containing aromatic heterocyclic residues having 3 to 11 carbon atoms are preferable. Specific examples thereof include a benzothiazolyl group, a benzoxazolyl group, and a benzimidazolyl group.

R¹, R²And R^FiveRepresents a halogen atom
If it is omitted, it is a chlorine atom, a bromine atom, or an iodine atom.
Is common, R¹, R², R^FiveAnd R⁶Is alkyl
If it represents a group or an alkoxy group, is it a synthetic reason?
A lower alkyl group or lower alkoxy group
Is preferred, and particularly, an alkyl group having 1 to 4 carbon atoms or an alkyl group
It is preferably a Coxy group. R¹, R², R^Fiveas well as
R⁶Each is preferably a hydrogen atom or a lower alkyl group.
Yes. R³And R^FourWhen represents an alkyl group, synthetically
It is common to represent a methyl group or an ethyl group for
Target. R³And R ²And / or R^FourAnd R^FiveOr
R³And R^FourAre linked to each other to form a substituted or unsubstituted alkyl group.
When forming a len group, it generally has 1 to 5 carbon atoms.
And the substituent is, for example, an alkyl group or an alkoxy group.
Group, halogen atom, aryl group, acyl group, carboxy
And the like.

Of these, a substituent R ^{3 of} the amino group at the 7-position,
The R ^4, R ³ and R ^2, R ⁴ at least one of the one pair substitutions in combination with R ^5, an unsubstituted propylene group, more preferably 3,3-dimethyl-1,3-propylene group And a structure in which it is linked to a benzene ring is preferred. In particular, it is preferable that the carbon atom at the 1-position of the 3,3-dimethyl-1,3-propylene group is bonded to the nitrogen atom. The heterocyclic residue of R ⁷ is preferably one containing a thiazole ring or an oxazole ring. Below, the general formula [I]
Typical examples of the compound represented by are shown below, but these should be understood as examples until a moment.

[0024]

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[0025]

[Chemical 6]

[0026]

[Chemical 7]

[0027]

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Next, the compound of the third component (c) of the photopolymerization initiation system of the present invention will be described. As described above, one or more of the compounds represented by the general formula (II), (III) or (IV) are used. General formula (II)
To (IV), R ^{9 to} R ¹⁸ are preferably lower alkyl groups, particularly preferably C 1 to C 4 alkyl groups, and R ⁸ is more specifically C 1 to C 20 alkyl groups. , Preferably 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms
The following alkyl groups may be linear or may have a branched structure. The alkyl group of R ⁸ may be further substituted with a substituent such as a halogen atom, an aryl group, an acyl group, a carboxyl group or an alkoxy group.

Specific examples of the compounds represented by the general formulas (II) to (IV) include p-dimethylaminobenzoic acid ethyl ester (hereinafter abbreviated as C-1) and p-.
Diethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isopropyl ester, p-dimethylaminobenzoic acid-n-butyl ester, p-dimethylaminobenzoic acid-n-octyl ester or p-di-n-
Dialkylaminobenzoic acid alkyl ester such as butylaminobenzoic acid ethyl ester; 4,4′-bis (dimethylamino) benzophenone (hereinafter abbreviated as C-2),
Bisaminobenzophenone such as 4,4'-bis (diethylamino) benzophenone or 4,4'-bis (diisopropylamino) benzophenone; 4,4'-bis (dimethylamino) benzyl (hereinafter abbreviated as C-3) or 4 , Bisaminobenzyl such as 4'-bis (diethylamino) benzyl. Among these, dialkylaminobenzoic acid alkyl ester is particularly preferable.

With respect to the above-mentioned compound (C), particularly with respect to dialkylaminobenzoic acid alkyl ester,
Conventionally, it has been proposed as a co-component or an additive of a photopolymerization initiator. However, as a result of various studies, we did not always show an effective addition effect, and especially for a highly sensitive photopolymerization initiation system, depending on the combination of components of the co-initiator system, it was completely ineffective. It was found that there are many systems that cause a decrease in sensitivity during storage even if the initial sensitivity is improved. On the other hand, the effect of adding the component (c) to the high-sensitivity photopolymerization initiation system, which is a combination of the components (a) and (b) in the system of the present invention, not only improves the sensitivity but also has good storage stability. I found something to bring.

The amount of each of the components (a), (b) and (c) of the photopolymerization initiation system of the present invention described above is 0.2 to 40% by weight of the component (a) with respect to the ethylenic compound. 0.1 to 20% by weight of component (b) and 0.
The range of 1-40% by weight is preferred. Particularly preferable amounts of the component (a) are 1 to 30% by weight, (b) is 0.5 to 15% by weight, and component (c) is 1 relative to the ethylenic compound.
Is in the range of up to 30% by weight.

In the photopolymerizable composition of the present invention, in addition to the above-mentioned constituents, an organic polymer substance may be further added as a binder for the purpose of modifying the composition and improving the physical properties after photocuring. it can. The binder may be appropriately selected according to the purpose of improving compatibility, film forming property, developability, adhesiveness and the like. Specifically, for example, for improving aqueous developability, acrylic acid copolymer, methacrylic acid copolymer, itaconic acid copolymer, partially esterified maleic acid copolymer, modified acidic cellulose having a carboxyl group in a side chain, Examples include polyethylene oxide and polyvinylpyrrolidone. To improve film strength and adhesion, a polyether of epichlorohydrin and bisphenol A; soluble nylon; alkyl polymethacrylate such as polymethylmethacrylate or alkyl polyacrylate; alkyl methacrylate and acrylonitrile, acrylic acid, methacrylic acid , Copolymers with vinyl chloride, vinylidene chloride, styrene, etc .; copolymers with acrylonitrile and vinyl chloride, vinylidene chloride; vinylidene chloride, chlorinated polyolefins, copolymers with vinyl chloride and vinyl acetate; polyvinyl acetate; Acrylonitrile / styrene copolymer; Acrylonitrile / butadiene / styrene copolymer; Polyvinyl alkyl ether; Polyvinyl alkyl ketone; Polystyrene; Polyamide; Polyurethane; Polyethylene terephthalate isophthalate Mention may be made of acetyl cellulose and polyvinyl butyral. These binders can be added and mixed in a weight ratio of generally 500% or less, preferably 200% or less with respect to the ethylenic compound.

The photopolymerizable composition of the present invention may further contain a thermal polymerization inhibitor, a coloring agent, a plasticizer, a surface protective agent, a smoothing agent, if necessary.
Coating aids and other additives can be added. Examples of the thermal polymerization inhibitor include hydroquinone, p-methoxyphenol, pyrogallol, catechol, and 2,6-di-
There are t-butyl-p-cresol, β-naphthol, and the like. Examples of the colorant include phthalocyanine pigments, azo pigments, carbon black, pigments such as titanium oxide, ethyl violet, crystal violet, azo dyes, anthraquinone dyes. , There are cyanine dyes. When the binder is used, the thermal polymerization inhibitor and the colorant are added in an amount of 0.01 to 5% of the thermal polymerization inhibitor and 0.1% of the colorant with respect to the total weight of the ethylenic compound and the binder. ~ 4
0% is preferable.

Examples of the plasticizer include dioctyl phthalate, didodecyl phthalate, triethylene glycol dicaprylate, dimethyl glycol phthalate, tricresyl phosphate, dioctyl adipate, dibutyl sebacate, triacetyl glycerin, and the like. When used, 30% or less is generally added to the total weight of the ethylenic compound and the binder.

When using the photopolymerizable composition of the present invention,
The light-sensitive material can be prepared by forming the light-sensitive material without a solvent or dissolving it in a suitable solvent to form a solution, which is coated on a support and dried. Examples of the solvent include methyl ethyl ketone, cyclohexanone, butyl acetate, amyl acetate, methyl lactate, toluene, xylene, monochlorobenzene, carbon tetrachloride, trichloroethylene, trichloroethane, dimethylformamide, methyl cellosolve, ethyl cellosolve, tetrahydrofuran, bentoxone, propylene glycol methyl ether acetate. Etc., and one kind or two or more kinds can be used in combination.

The support applied when preparing a light-sensitive material using the photopolymerizable composition of the present invention may be any of those usually used. For example, a sheet of metal such as aluminum, magnesium, copper, zinc, chromium, nickel, iron or an alloy containing them as a main component; high-quality paper, art paper,
Papers such as release paper; inorganic sheets such as glass and ceramics; polyethylene terephthalate, polyethylene, polymethylmethacrylate, vinyl chloride, vinyl chloride-vinylidene chloride copolymer, polystyrene, 6-nylon, cellulose triacetate, cellulose acetate butyrate, etc. Polymer sheets, etc.

Further, the photopolymerizable composition of the present invention is further provided with a known technique for preventing adverse effects such as sensitivity deterioration and storage stability deterioration due to oxygen, for example, providing a peelable transparent cover sheet on the photosensitive layer. Wax-like substance with low oxygen permeability,
It is also possible to provide a coating layer made of a water-soluble polymer or the like.
The exposure light source applicable to the composition of the present invention is not particularly limited, but carbon arc, high pressure mercury lamp, xenon lamp, metal halide lamp, fluorescent lamp, tungsten lamp, helium cadmium laser, argon ion laser, YAG laser, etc. of 400 nm or more. A general-purpose light source including visible light can be used more suitably.

[0038]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded. Examples 1 to 20, Comparative Examples 1 to 10 Methyl methacrylate / methacrylic acid copolymer (weight average molecular weight 45,000, polymerization ratio 85/15) 2 g and trimethylolpropane triacrylate 2 g were dissolved in methyl ethyl ketone 36 g. . To this, 80 mg of the photoinitiator component, that is, the titanocene compound A-1 which is the component (a).
And 80 mg of the coumarin compound of component (b) and 200 mg of the compound of component (c) shown in Table 1 were added and dissolved to obtain a sample photosensitive solution. Apply this to a grained and anodized aluminum sheet using a whirler to a dry film thickness of 2 μm, and then apply a polyvinyl alcohol aqueous solution to the surface to a dry film thickness of 3 μm. Then, a photosensitive material sample was prepared.

Next, a xenon lamp; UI-501C manufactured by USHIO INC. Was used as a sample of this photosensitive material, and a spectral sensitivity measuring device manufactured by Narumi Co., Ltd. was used so that the abscissa axis represents wavelength and the ordinate axis represents logarithmically weak light intensity. For 10 seconds. The exposed sample was developed with an aqueous solution containing 6% by weight of butyl cellosolve and 1% by weight of sodium silicate, and the minimum amount of exposure required for photocured image formation was calculated from the height of the cured image corresponding to each wavelength obtained. Then, the sensitivity of each wavelength of the photosensitive composition was used. The results are shown in Table 1. All the sensitivities described below are shown as energy values corresponding to a light beam of 488 nm.

[0040]

[Table 1]

Examples 18 to 20 described below are components C-1
It is shown that the effect of improving the sensitivity by the addition of is stably maintained. On the other hand, in the case of another high-sensitivity photoinitiating system containing titanocene used in Comparative Examples 9 and 10, no increase in sensitivity due to the addition of C-1 was observed, or the effect was not too temporary. Example 18 The same sample as in Example-4 was allowed to stand at room temperature for 4 months and then the sensitivity was measured. As a result, the sensitivity was 53 μJ / cm ^2, and the sensitivity characteristics were maintained. In addition, no change in appearance was observed.

Example 19 The same sample as in Example-10 was allowed to stand at room temperature for 4 months and then the sensitivity was measured. As a result, the sensitivity was 38 μJ / cm ² , the sensitivity characteristics were maintained, and no change in appearance was observed. Example 20 The same sample as in Example-13 was allowed to stand at room temperature for 4 months and then the sensitivity was measured. As a result, the sensitivity was 44 μJ / cm ² , the sensitivity characteristics were maintained, and no change in appearance was observed.

Comparative Example 9 In Example 4, except for B-2 and C-1, the sensitizer 2,4,6-tris- (p-dimethylaminostyryl) -1,3,5-triazine was added to B-. When the same amount as 2 was added, it showed 240 μJ / cm ² . In addition to this, C
When -1 was added in the same manner, no increase in sensitivity was observed.

Comparative Example 10 Except for B-2 and C-1 in Example 4, the sensitizer 2- [4- (p-dimethylaminophenyl) -1,3 was first prepared.
-Butadienylnaphtho [1,2-d] thiazole was added to B-
The same amount as 2 was added. In this case, it showed 350 μJ / cm ^2, and the same sensitivity was maintained even after 4 months at room temperature. On the other hand, when C-1 was added to this in the same manner, the sensitivity was 260 μJ / c.
Although it increased to m ² , it was found to have a sensitivity of 340 μJ / cm ² as a result of sensitivity measurement after 4 months at room temperature. Since no abnormalities were observed in appearance, the decrease in sensitivity was C-
It shows that the effect of addition of 1 disappeared.

[0045]

The photopolymerizable composition of the present invention has extremely high sensitivity to visible light and is excellent in storage stability over time.
Therefore, the composition is useful in a wide range of application fields, for example, printing plates such as planographic printing, intaglio printing, letterpress printing, photoresists for printed wiring and IC, dry film, images such as relief images and image duplication. It is industrially very useful because it can be used for forming, photocurable ink, paint, adhesive and the like.

Claims (1)

[Claims] 1. A photopolymerizable composition comprising a compound having at least one ethylenically unsaturated double bond capable of addition polymerization and a photopolymerization initiation system, wherein the photopolymerization initiation system comprises:
(A) a titanocene compound, (b) at least one coumarin compound represented by the following general formula [I]: [In the formula, R ¹ , R ² and R ⁵ each represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group,
R ³ and R ⁴ each represent an alkyl group, provided that at least one set of R ³ and R ² and R ⁴ and R ⁵ or R
³ and R ⁴ may be linked to each other to form a substituted or unsubstituted alkylene group, and R ⁶ is a hydrogen atom, an alkyl group, an acyl group, a cyano group, a carboxyl group or an ester derivative or amide derivative thereof. Represents a group of R;
⁷ represents a heterocyclic residue having a total of 3 to 17 carbon atoms. ], And (c) at least one compound represented by the following general formula [II], [III] or [IV]: [In the formula, R ^{8 to} R ¹⁸ each represent an alkyl group. ]
A photopolymerizable composition comprising: