JPS5912166B2 - Photosensitive composition for image formation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photosensitive composition for image formation in which a colored image is directly printed out by irradiation with light and then a fixed image is obtained by applying heat.

The photosensitive composition for image formation of the present invention is characterized by a reduction in fog density in non-image areas and an improvement in r value, compared to conventional photosensitive compositions for image formation of this type. It is something.

A photosensitive composition that combines an essentially colorless dye that develops color when it comes into contact with an acidic substance used in pressure-sensitive recording paper, etc., and an organic compound that can generate free radicals when irradiated with light, is Formation of colored images is already known, for example, in Japanese Patent Publication No. 38-24188, Japanese Patent Publication No. 49-204, and Japanese Patent Application Laid-open No. 1262-1983.
28, JP-A-53-73133, and the like.

However, the image-forming photosensitive compositions found in the above-mentioned known documents exhibit drawbacks such as high fog density in non-image areas, low γ values, and only soft-tone images. As a result of intensive research to improve the above-mentioned drawbacks, the present inventors found that (a) organic halogen compounds that can generate free radicals when irradiated with light, and (b) essentially colorless compounds that develop color upon contact with acidic substances. dye, (c) aromatic amine and or conjugated nitrogen-containing heterocyclic compound, (d) binder and (e
) A photosensitive composition comprising an aliphatic amine and/or a cycloaliphatic amine has been discovered.

The photosensitive composition of the present invention will be explained in more detail below. (a) Organic halogen compounds capable of generating free radicals upon light irradiation are, for example, compounds of the general formula (a) R-CX3 (wherein R is an aryl group, an alkyl group, an allyl group, an aroyl group, an alkenyl group, or a hydrogen atom). , a halogen atom or a heterocyclic residue, and X represents a halogen atom), carbon tetrabromide, iodoform, hexachloroethane, 2,2,2-tribromoethanol, p-nitrobenzotrichloride, benzotribromide, a
・α・α●α5・α5・α5-hexachloroxylene,
Dichlorobromomethane, 2-ω・ω・ω-1 trichloromethyl-6-nitrobenzothiazole, ω・ω・ω-1 tripromoquinaldine, 4-ω・ω・ω-1 tripromomethylpyridine, (B) (Formula Q represents an amino group, alkylamino group, aralkylamino group, arylamino group, aryl group or allyl group, and X represents a halogen atom.

), such as trichloroacetamide, N-ethyl-tribromoacetamide, p-nitro-α・a・α-tripromoacetophenone, α・α・α
monotrichloroacetophenone, (c) (in the formula, W.Y.Z represents a hydrogen atom, a chlorine atom or a bromine atom, but all three cannot be hydrogen atoms at the same time.

A is an aryl group, an alkyl group, an allyl group, or a Cy
Based on W. YlZ is the same as the previous definition, but in this case, the three atoms may be hydrogen atoms.

), such as pentabromodimethylsulfoxide, hexapromodimethylsulfone, trichloromethyl-phenylsulfon, hexachlorodimethylsulfon, 2-tribromomethylsulfonyl-6-methoxy-benzothiazole, 1-methyl −
These include 2-tribromomethylsulfon-benzimidazole, 2-tribromomethylsulfonyl-5-nitro-benzothiazole, and the like.

(b) As a coloring agent, an essentially colorless dye that develops color upon contact with an acidic substance is, for example, 3.3-
Bis-(4'-dimethylaminophenyl)-6-dimethylaminoptalade, 3-(4'-dimethylaminophenyl)-3-(1',2'-dimethylindole-31
-yl)-Pthalad dyes, 3-diethylamino-J[dibenzylaminofluoran, 3-diethylamino-benzo-(c)-fluoran and other fluoran dyes, 1.3. 3-trimethylindolinobenzospiropyran, 7-diethylamino-3/-phenyl-2,2'-spirobi(2H-1
-benzopyran) and triphenylmethane dyes such as bis-(p-dimethylaminophenyl)-phenylmethane.

(c) The aromatic amine and/or conjugated nitrogen-containing heterocyclic compound as a sensitizer and storage stability improver is, for example, (a) a general formula (wherein R1 and R2 are a hydrogen atom and a phenyl group, represents a hydrogen atom, a halogen atom, and a methyl group.

), such as diphenylamine,
p-Toluidine, p-chloroaniline triphenylamine, hydrogen (in the formula, R3 is a hydrogen atom and a lower alkyl group, R4 is a hydrogen atom, a lower alkyl group, and a phenyl group, R5, R
6 and R7 are hydrogen atoms, R4 and R5 and R6 and R7
and represent residues that can be bonded together to form a benzene ring.

), carbazole, N-methylcarbazole, N-ethylcarbazole, indole, 2-
Phenylindole, 2-methylindole, 1,2-
Dimethylindole, N-ethyl-2-phenylindole, 2-phenylpyrrole, (wherein Y represents an oxygen atom or an imino group, and R8 represents a hydrogen atom or a phenyl group.

) Aromatic amines such as 2,5-diphenyloxazole, 2-phenyloxazole, imidazole, 2-phenylimidazole and/or
Alternatively, conjugated nitrogen-containing heterocyclic compounds can be preferably mentioned.

]) Examples of the binder include polymeric compounds such as polystyrene, ethyl cellulose, polyvinyl acetate, polyvinylidene chloride, polymethyl methacrylate, butyral resin, polycarbonate, vinyl chloride monovinyl acetate copolymer resin, and styrene-butadiene copolymer resin. I can do it.

(e) The aliphatic amine or cycloaliphatic amine used for reducing the fog density in the non-image area and improving the γ value is (a) (b) (wherein, R9 and RIOlRll are hydroxyl groups or amino These include an alkyl group having 2 to 20 carbon atoms which may be substituted with a group, a hydrogen atom, a benzyl group, and a cyclohexyl group.

However, R,, RlO. Aliphatic amines represented by Rll, which do not simultaneously remove hydrogen atoms, such as butylamine, pentylamine, nonylamine, octadecylamine, dodecylamine, benzylamine, cyclohexylamine, dioctylamine, didodecylamine, tridecylamine, tridecylamine, Ethanolamine, 1,8-diaminooctane (in the formula, z represents a methylene group or an imino group.

). Amine compounds having a dissociation constant PKa of 7.5 or more, such as cycloaliphatic amines represented by, for example, piperidine and piperazine, are particularly preferably used.
9. It is more than O.

In carrying out the method of the present invention, the photosensitive composition for image formation is prepared by adding 1.0 to 3.0 parts of an organic halogen compound,
1.0 parts to 5.0 parts of a coloring agent, 0.5 parts to 3.0 parts of an aromatic amine and or a conjugated nitrogen-containing heterocyclic compound, and 5.0 parts to 8.0 parts of a binder and 0.02 parts ~ 0
．． It can be easily obtained by dissolving 7 parts of an aliphatic amine and/or a cycloaliphatic amine in 100 parts of an organic solvent under a safety light.

Furthermore, if necessary, 0.5 to 3.0 parts of a ferrocene compound can be added as a sensitizer. Examples of organic solvents preferably used in this case include benzene,
Toluene, xylene, tetrahydrofuran, acetone,
Examples include methyl ethyl ketone, cyclohexanone, acrylonitrile, methanol, ethanol, methyl cellosolve, ethyl cellosolve, ethyl acetate, dioxane, and mixed solvents thereof can also be suitably used. Further, in the preparation of a photosensitive sheet using the photosensitive composition for image formation of the present invention, paper, baryta paper, synthetic paper, synthetic resin film, etc. is used as a support,
This can be easily carried out by applying the photosensitive liquid under a safety light using spin coating, a roll coater, a blade method, or the like.

EXAMPLES The present invention will be explained in detail with reference to Examples below, but these are not intended to limit the scope of the present invention.

In addition, parts in Examples and Reference Examples represent parts by weight unless otherwise specified. The image density and fog density are measured using a Maghes reflection densitometer RD-519 model or a Maghes transmission densitometer TD-504 model. Example 1 3,3-bis-(47-dimethylaminophenyl)-6
-2.9 parts of dimethylaminoptalade, 2.9 parts of carbon tetrabromide.
0 parts, 2.1 parts of 2-phenylindole, 6.9 parts of polystyrene and octadecylamine (PKa -10.60
) was dissolved in a mixed solvent consisting of 71.5 parts of toluene and 16.6 parts of methyl ethyl ketone to prepare a photosensitive liquid.

Using this photosensitive liquid as a support, it was coated on NK Ecoat paper (manufactured by Nippon Kako Paper Industries Co., Ltd.) at a rate of 5.07/m" and dried to obtain a photosensitive paper for image formation. This photosensitive paper A step tablet made by Kodatsu is closely attached to the vacuum baking frame (
Dainippon Screen Manufacturing Co., Ltd. p-113-B, 20
The film was exposed to light for 3 minutes using a W chemical lamp) and heated and fixed for 2 minutes using a hot air dryer at 110° C. to obtain a clear blue image.
The resulting image density was measured, and the horizontal axis was the exposure amount E (lux seconds) converted to -10 gE, and the vertical axis was the density to obtain a photographic characteristic curve. The γ value was measured from the characteristic curve. As a reference example, a photosensitive solution was prepared by removing octadecylamine from the photosensitive solution composition of Example 1, and processed in the same manner as in Example 1 to obtain a blue image.

(Reference example 1). The above results are shown in Table-1. From the above results, the effect of adding octadecylamine according to the present invention is obvious.

Example 2 A photosensitive solution prepared by adding 2.0 parts of ferrocene to the photosensitive solution composition of Example 1 was processed in the same manner as in Example 1 under a red safety light to obtain a clear blue image.

As a reference example, a photosensitive solution of Example 2 excluding octadecylamine was prepared and processed in the same manner as in Example 1 to obtain a blue image.

(Reference example 2). The above results are shown in Table-2. From the above results, the effect of adding octadecylamine is obvious.

Example 3 3-diethylamino-benzo-(c)-fluorane3.
5 parts, carbon tetrabromide 33 parts, 2-phenylimidazole 1
．． 0 parts, pentylamine (PKa - 10.66) 0.4
5 parts of polystyrene and 10.0 parts of polystyrene were dissolved in a mixed solution consisting of 130 parts of xylene and 20 parts of methyl ethyl ketone, and this photosensitive solution was processed in the same manner as in Example 1 using a polyester pool as a support to produce a purple-red image. I got it.

As a reference example, a photosensitive solution was prepared by removing pentylamine from the photosensitive composition of Example 3, and processed in the same manner as in Example 3.
A purple-red image was obtained.

(Reference example 3). The above results are shown in Table 3. From the above results, the effect of the addition of pentylamine is obvious.

Example 4 4.7 parts of 3,3-bis-(1,2-dimethylindol-3-yl)-6-dimethiaminophthalide, 4.0 parts of iodoform, 4.0 parts of N-ethylcarbazole, dodecylamine ( PKa-10.63) and 7.0 parts of butyral resin (Eslec BM-2, manufactured by Sekisui Chemical Co., Ltd.) were dissolved in 150 parts of tetrahydrofuran to prepare a photosensitive solution, and treated in the same manner as in Example 1. , a red image was obtained.

As a reference example, a photosensitive solution was prepared by removing dodecylamine from the photosensitive solution composition of Example 4, and processed in the same manner as in Example 4 to obtain a red image.

(Reference example 4). The above results are shown in Table-4. From the above results, the effect of adding dodecylamine is clear.

Example 5-12 Using a photosensitive solution having the composition shown in Table 5, the same method as in Example 1 was used to obtain clear colored images.

Claims (1)

[Scope of Claims] 1 (a) Organic halogen compounds that can generate free radicals when irradiated with light, (b) Phthalide dyes, fluoran dyes, spiropyran dyes, and triphenylmethane that develop color upon contact with acidic substances. Essentially colorless dyes, (c) General formulas I, II, III ▲Mathematical formulas, chemical formulas, tables, etc.▼……(I) (In the formula, R_1 and R_2 are hydrogen atoms and phenyl groups (X represents a hydrogen atom, a halogen atom, and a methyl group.) ▲Contains mathematical formulas, chemical formulas, tables, etc.▼……………………(
II) (wherein R_3 is a hydrogen atom and a lower alkyl group,
R_4 is a hydrogen atom, a lower alkyl group and a phenyl group,
R_5, R_6 and R_7 are hydrogen atoms, R_4 and R_
5, R_6 and R_7 each represent a residue capable of bonding to form a benzene ring. )▲There are mathematical formulas, chemical formulas, tables, etc.▼…………………………(
III) (wherein R_8 is a hydrogen atom and a phenyl group, Y
represents an oxygen atom and an imino group. ), and (d) a binder, the following general formula (IV), (
e) General formulas (IV), (V)▲There are mathematical formulas, chemical formulas, tables, etc.▼…………………………(IV)▲There are mathematical formulas, chemical formulas, tables, etc.▼……………………(V ) (in the formula, R_9, R_1
—0 and R_1_1 are an alkyl group having 2 to 20 carbon atoms which may be substituted with a hydroxyl group or an amino group, a hydrogen atom, a benzyl group, or a cyclohexyl group, and z represents a methylene group or an amino group. However, R_9, R_1_0, and R_1_1 do not have hydrogen atoms at the same time. ) A photosensitive composition for image formation, characterized in that an amine compound having a pKa of 7.5 or more is added.