JPH0437852A - Photopolymerizing photosensitive body and image forming method - Google Patents

Abstract

PURPOSE:To attain a recording with semiconductor laser beam and to obtain a stable image of high-definition by incorporating a semiconductor laser photosensitive photopol ymerization sensitizer, a polymerization initiator, a reactive binder and a thermal diffusion type dyestuff. CONSTITUTION:As the sensitizer acting efficiently at >= 600 nm of wavelength light and incorporating as a cation dye structure, for example, a polymethylene system dye, is used, it has a wider width of an absorbing peak, and it can easily correspond to the variation of the wave length due to a temp. of the semiconductor laser and the variation of the wavelength due to the variations between the lots. The polymeriza tion initiator is a radical generated from the polymerization, for example, an amine compound is used. Next the reactive binder is preferably a high polymer compound having a polymerized unsaturated double bond, for example, an acryl group, etc. The thermal diffusion type dyestuff is an azo type dispersion dye, etc., which diffuses thermally or sublimes thermally with heating at 90-200 deg.C. When exposed with the laser beam, an exposed part is hardened and next an image receiving body 10 is confronted with a protective layer 4 or is laminated with a polymerized layer 3 after the protective layer is stripped, then heated. Thus, the desired pigment image 12 is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a photopolymerizable composition and an image forming method using the same, and more specifically, to a method for forming a Victorian image using a heat-diffusible dye. The present invention relates to a photopolymerizable composition and an image forming method.

[Prior art 1] A method of obtaining an image by curing or decomposing a photosensitive layer by exposure and then transferring dyes or pigments to an image receptor depending on the degree of curing or decomposition is disclosed in JP-A-61-45241.
It is stated in the No.

[Problem that the invention is trying to solve]

However, the above method has inferior photosensitivity, and the sensitive wavelength is a short wavelength in the near-ultraviolet region, making digital exposure impossible.
Color capri occurs in the highlight areas on the image receptor, wet processing such as etching is required because the maximum optical density cannot be obtained high, and manufacturing costs are high because the photoreceptor is coated with pigments. There is a problem.

An object of the present invention is to provide a photopolymerizable photoreceptor and an image forming method that solve the above problems.

In other words, it has excellent photosensitivity and is sensitive to laser wavelengths, so digital exposure is possible; the resulting image has sufficient contrast, which is the difference between the maximum and minimum optical density; it is a completely dry process, and the manufacturing cost is low. An object of the present invention is to provide a photopolymerizable composition and an image forming method that are inexpensive.

[Means for Solving the Problems (and Effects)] The present invention provides a photopolymerizable photosensitive material characterized by containing a semiconductor laser photosensitive photopolymerization sensitizer, a polymerization initiator, a reactive binder, and a heat-diffusible dye. It is the body.

Further, the present invention is characterized in that after the photoreceptor is imagewise exposed to light using a semiconductor laser, the photoreceptor is placed on an image receptor and heated, thereby transferring the thermally diffusible dye in the unexposed portion of the image to the image receptor. This is an image forming method.

The object of the present invention is achieved by a photopolymerizable photoreceptor containing at least a semiconductor laser-sensitive sensitizer of the following formula (1), a polymerization initiator, a reactive binder, and a heat-diffusible dye.

Here, the semiconductor laser photosensitizer is a sensitizer that can efficiently generate initiating species that initiate polymerization or crosslinking using light with a wavelength of 600 nm or more. Therefore, exposure can be performed using an exposure means other than a semiconductor laser.

Here, "Dye" is a cationic dye skeleton having an absorption maximum at 600 nm or more. R1, R2, R3 and R4 are:
It is a group selected from an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, and a heterocyclic group.

The alkyl group used for R' to R4 above is preferably a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and t-butyl. ,
amyl, isoamyl, octyl, trifluoromethyl,
These include methoxymethyl, ethoxymethyl, methchelisopropyl, ethoxypropyl, N,N-dimethylaminoethyl, N,N-dimethylaminopropyl, and the like.

The cycloalkyl group preferably has 5 to 8 carbon atoms, such as cyclopentyl group, cyclohexyl group,
Examples include cyclohebutyl group, cyclooctyl group, etc.
These may be substituted with an alkyl group or the like.

The aryl group is a substituted or unsubstituted aryl group, such as phenyl group, naphthyl group, fluorophenyl group, chlorophenyl group, dichlorophenyl group, methoxyphenyl group, tolyl group, xylyl group, ethylphenyl group, N, N- These include dimethylaminophenyl group, chloronaphthyl group, methoxynaphthyl group, and diphenylaminophenyl group.

Examples of the aralkyl group include substituted or unsubstituted aralkyl groups such as benzyl group, phenethyl group, α-naphthylmethyl group, β-naphthylmethyl group, p-methoxybenzyl group, and p-chlorobenzyl group.

Examples of the heterocyclic group include a pyridyl group, a quinolyl group,
Examples include levidyl group, methylbilidyl group, furyl group, thienyl group, indolyl group, virol group, carbazolyl group, N-ethylcarbazolyl group, and the like.

Tetramethylborate, tetraethylborate,
Tetrabutylborate, triisobutylmethylborate, di-t-butyl-dibutylborate, trifluoromethyltrinotetraoborate, tetra-n-butylborate, tetraphenylborate, tetra p-chlorophenylborate, tetraanisborate, triphenylmethylborate , triphenylethylborate, triphenylpropylborate, triphenyl-n-butylborate, trianisbutylforate, triphenylhexylborate, trimeditylbutylborate, tritolylisopropylborate, triphenylbenzylborate,
Tetraphenylborate, tetrabenzylborate, triphenylphenethylborate, triphenyl-p-chlorobenzylborate, trimethallylphenylborate, tricyclohexylbutylborate, tri(phenylethynyl)butylborate, di(α-naphthyl)dipropylborate, Examples include diisopinocamphenyl diamylborate, and diphenyldibutylborate, triphenylbutylborate, tetraphenylborate, and trifluoromethyltrinoroloborate are particularly preferred.

A boron anion can be obtained by reacting a boron compound such as triarylboron or boron trifluoride with a nucleophilic reagent such as a lithium compound or Grignard reagent.

Examples of the cationic dye skeleton Dye include polymethine dyes, cyanine dyes, azulene dyes, fluorene dyes, and rhodamine dyes, preferably polymethine dyes having an aniline group, azulene dyes with an asymmetric structure, and fluorene dyes. It is a pigment based on pigments.

In particular, polymethine dyes with an aniline group and asymmetric azulene dyes have broader absorption peaks than cyanine dyes and carbocyanine dyes, and cannot cope with wavelength changes caused by semiconductor laser temperature and lot-to-lot variations. It has the advantage of being easy.

Specific examples of cationic dye skeletons are listed below.

Kushikushi ω Hs Furthermore, other cationic dyes such as cyanine, carbocyanine, hemicyanine, rhodamine, and azamethine dyes may be used in combination without departing from the spirit of the present invention.

The polymerization initiator is one that receives radicals generated by the excitation of the sensitizer and substantially initiates polymerization,
Examples include amine compounds, halogen compounds, and thiol compounds.

Examples of amine compounds include triethanolamine,
Examples include ethyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, p-dimethylaminobenzonitrile, and p-dimethylaminoacetonephenone.

Examples of halogen compounds include carbon tetrabromide, tribromomethane, a, a, α-trichloroacetophenone,
Examples include 1,3.5-tris(trichloromethyl)-s-triazine and 1,3-bis(trichloromethyl)-5-hydroxyethyl-8-triazine.

Examples of thiol compounds include 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole.
Mercaptobenzimidazole, 2-mercapto-1-
Examples include methyl-benzimidazole.

Next, as the reactive binder, a polymer compound having a polymerizable unsaturated double bond in its side chain is selected. The polymerizable unsaturated double bond in the side chain is preferably an acrylic group, a metallurgical group, or a styrene vinyl group, and in particular, an acrylic group or a methacryl group is bonded to the polymer main chain by an ester bond, an amide bond, or a urethane bond. The content of unsaturated double bonds in one molecule is preferable for synthesis, and may have a polymerizable functional group at the end of the main chain, although it depends on the structure of the polymer main chain. , preferably from 1 mol% to 99 mol%, based on the main chain block that may have side chains, preferably 5
mol% to 60 mol%, more preferably 8 mol% to 4
It is 0 mol%.

Here, to explain the mol% of unsaturated double bonds,
For example, when acrylic acid chloride is reacted with the hydroxyl group of polyvinyl alcohol (PVA) to bond an acrylic group, the OH value before and after the reaction, or the OH value of the reactant and the OH value after the acrylic group of the reactant is removed. The bonding ratio of acrylic groups can be calculated from the difference. Alternatively, it may be calculated using a spectroscopic method such as NMRlIR. Alternatively, it can also be calculated using the consumption amount of reaction reagents such as halogen required to saturate unsaturated double bonds. In the case of PVA, the main chain block is -CH(OH)CH
It becomes z-.

In addition, low molecular weight compounds, so-called monomers, can be contained as polymerizable compounds.

As such, monomers having a structure having one or more polymerizable unsaturated double bonds can be used, preferably monomers having two or more, and particularly preferably monomers having four or more. Examples of such tetrafunctional or higher functional monomers include:
Tetramethylolmethanetetraacrylate, tetramethylolmethanetetramethacrylate, ethylenetetraacrylamide, propylenetetraacrylamide, ethylenetetramethacrylamide, dipentaerythritol hexaacrylate, hexa(acryloxyethoxy)cyclotriphosphazene, hexa(methacryloxyethoxy) Examples include cyclotriphosphazene. Among these, dipentaerythritol hexaacrylate, hexa(acryloxyethoxy)cyclotriphosphazene, hexa(methacryloxyethoxy)cyclotriphosphazene, and the like are particularly preferred.

As the heat-diffusible dye, azo-based, polymethylene-based, naphthoquinone-based, and anthraquinone-based disperse dyes, azomethine-based, indoline spirobilane-based, phenoxazine-based, and leucoauramine-based basic dyes are used, and the dyes have a molecular weight of 90 to 200.
A material that thermally diffuses or thermally sublimates when heated at ℃ is used.

In a preferred embodiment of the photoreceptor of the present invention, as shown in FIG. 1, a color material layer 2 containing a heat-diffusible dye, a semiconductor laser-sensitive photopolymerization sensitizer, a polymerization initiator, and a reactive binder are provided on a support 1. It takes a multilayer configuration with a polymeric layer 3 containing. As the support 1, paper, baryta paper, synthetic paper, plastic film, etc. are used. An intermediate layer and an antihalation layer may be provided between the coloring material layer 2 and the polymerization layer N3 so that the heat-diffusible dye of the coloring material layer is not mixed into the polymerization layer during the coating process. 4 is a protective layer, which may be made of the same material as the support 1 or may be made of a different material.

The thickness of the coloring material layer 2 is from 0.1 μm to 10 μm, especially 0.5 μm.
The thickness of the polymer layer 3 is preferably 0.5 μm to 4 μm.
m to 19 μm, particularly 1 μm to 7 μm.

The thickness of the polymer layer 3 is related to the amount of dye contained in the coloring material layer and the thickness, since increasing the thickness of the polymer layer 3 lowers the maximum optical density of the transferred image on the image-receiving material, and decreasing the thickness of the polymer layer 3 increases the minimum optical density.

The blending ratio of the sensitizer is 1 part to 20 parts with respect to 100 parts (parts indicate parts by weight; the same applies hereinafter) of the solid content of the above polymerized layer.
Particularly preferably from 2 parts to 15 parts, the polymerization initiator from 1 part to 20 parts, particularly preferably from 2 parts to 10 parts, and the reactive binder from 5 parts to 70 parts, particularly preferably from 10 parts to 40 parts. The monomer having four or more functional groups is preferably used in an amount of 0 to 70 parts, particularly preferably 10 to 40 parts.

In addition, a less than tetrafunctional monomer, a thermal polymerization inhibitor, a surfactant, an unreactive binder, an anti-irradiation dye, an antistatic agent, etc. can be added to the polymerization layer.

Non-reactive binders can be selected from a wide range of resins, including, for example, nitriculose, cellulose phosphate, cellulose sulfate, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose myristate, valmitic acid. Cellulose esters such as cellulose, cellulose acetate/propionate, cellulose acetate/butyrate; cellulose ethers such as methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose; e.g. polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl butylade, polyvinyl Vinyl resins such as acetal, polyvinyl alcohol, polyvinylpyrrolidone; e.g. styrene-butadiene copolymer, styrene-acrylonitrile
copolymers, such as styrene-butadiene-acrylonitrile copolymers, vinyl chloride-vinyl acetate copolymers; e.g. polymethyl methacrylate,
Acrylic resins such as polymethyl acrylate, polybutyl acrylate, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyacrylonitrile; polyesters such as polyethylene terephthalate; such as poly(4,4-impropylidene, diphenylene-
2-1,4-cyclohexylene dimethylene carbonate), poly(ethylene dioxy-3,3゛phenylene thiocarbonate), poly(4゜4゜-isobropylidene diphenylene carbonate coated terephthalate), poly(4゜, 4°-isopropylidene diphenylene carbonate), poly(4,4'-5ec-butylidene diphenylene carbonate), poly(4,4'-isopropylidene diphenylene carbonate-block oxyethylene) and other polyacrylate resins: Boryamides;
Examples include polyimides; epoxy resins; phenolic resins; for example, polyethylene/fins such as polyethylene, polypropylene, and chlorinated polyethylene; and natural polymers such as gelatin.

Next, the image forming method of the present invention will be described.

As shown in FIG. 2(a), when exposed to laser light according to the image information, the exposed portion 5 is hardened. Next, the image receiving layer 11
By heating the image receptor 10 with the protective layer 4 or peeling off the protective layer 4 and placing it with the polymer layer 3 (FIG. 2(b)), the dye in the unexposed area is absorbed into the image. The dye image 12 is formed on the image-receiving layer 11 (FIG. 2(C)).

A full-color image can be formed by repeating this process three times for yellow, magenta, and cyan.

For image exposure, use the above sensitizer to achieve a wavelength of 600 nm.
A laser that oscillates light with a wavelength of from to 850 nm can be used. In addition, it is recommended to use heating in combination with heating to accelerate the polymerization rate during this image exposure.
Preferably, it is heated to a temperature of 40°C to 70°C.

Further, this heating may be delayed by shifting the timing from the image exposure, and it is also preferable to use a heating method in which the temperature is gradually increased to a higher temperature. However, in order to suppress the diffusion of the heat-diffusible dye, it is necessary to perform the heating at a temperature lower than the heating temperature of the next transfer process.

The heating temperature during the transfer process is 90'C to 200°C, especially 1
The temperature is preferably from 00°C to 145°C, and pressure must be applied at the same time to ensure uniform adhesion between the photoreceptor and image receptor. The pressure to be applied is 1 kg/cm2 to 200 kg/c
m”, especially from 5 kg/cn+2 to 60 kg/cm
” is preferred.

As the heating method, a planar heating element, heat roll, galvanic heating, electrical heating, etc. can be used as appropriate.

[Example〕 Next, the present invention will be explained by giving examples.

Example 1 (Creation of photoreceptor) Solution A consisting of the following composition was prepared.

・Methyl methacrylate/butyl acrylate 8/2
Copolymer: 10 parts MS-Cyan-VP (manufactured by Mitsui Toatsu) -1,2 parts Methyl ethyl ketone 60 parts Coat this on polyethylene terephthalate (PET) film to a dry film thickness of 3 μm. Then, coloring material layer A was created.

In addition, a photosensitive solution B consisting of the following composition was prepared.

・Reactive binder with the following structural formula...50 parts (in the above structural formula, k = 10 mol%, 1 = 62%, m = 6 mol%
, n=22 mol%, and R is -CC)n=cH. ) ・Sensitizer with trianisbutylborate anion in cationic dye (5) ・1.8 parts ・Ethyl p-dimethylaminobenzoate ・5 parts ・Trimethylolpropane triacrylate ・2 .0 copies・
Hexa(acryloxyethoxy) cyclotriphosphazene...3.5 parts/p-
Methoxyphenol...0.02 parts, toluene...80 parts Photosensitive liquid B
was applied onto a polyacetate film to a dry film thickness of 6 μm to create a polymerized layer B. Laminate at a pressure of 40 kg/cm so that color material layer A and polymer layer B are in contact with each other,
A photoreceptor of Example 1 was obtained.

(Evaluation) While heating the photoreceptor to 50°C, 50 parts m x 50
Image exposure was carried out at a speed of 40 LLsee/dat with a dot diameter of um.

Next, the polyacetate film was peeled off, a coated paper (image receptor) having a polyester resin image-receiving layer (2 μm thick) was placed on top of the polymer layer, and the temperature was adjusted to 120°C and the temperature was adjusted to 20°C.
It was passed between heat rollers pressurized to kg/cm2. The nip width was 4 mm and the passing speed was 2 mm/sec.

When the coated paper was peeled off, a cyan image corresponding to the unexposed area of the image was formed.

Example 2 The polyacetate film of the photoreceptor of Example 1 was peeled off,
A layer of polyvinyl butyral was applied onto the polymer layer B to have a dry film thickness of 3 μm to prepare a photoreceptor of Example 2. After imagewise exposing this in the same manner as in Example 1, the polyvinyl butyral layer and the image receiving layer of the image receptor were overlapped so that they were in contact with each other, heated in the same manner as in Example 1, and the passing speed was set to 1.5 mm/sec.
Dye transfer was performed in c.

Although the maximum optical density of Bessian was slightly lower than that of Example 1, a clear image was obtained.

Example 3 The sensitizer was changed to 2.0 parts of a compound having a triphenylbutylborate anion in the cationic dye (2) (the absorption peak of this sensitizer in acetonitrile is shown in Figure 3).
, and 4.0 parts of a reactive binder with R having the following structure, k = 13 mol%, 1 = 65 mol%, m = 8 mol%, n = 14 mol%, and polyvinyl butyral as an unreactive binder. A photoreceptor of Example 3 was prepared in the same manner as Example 1 except that 20 parts of the photoreceptor was used.

(Evaluation) While heating this photoreceptor to 50° C., it was imagewise exposed to light using an 830 nm semiconductor laser (output 50 mW) at a speed of 12 μsec/dat with a dot diameter of 501 m×50 μm.

After peeling off the acetate film, it was stacked on the image receptor in the same manner as in Example 1 and passed between heat rollers at 110°C and 30 kg/cm'', and an image was formed on the image receptor.Lot of semiconductor laser Images with constant image quality were obtained regardless of changes in the oscillation wavelength due to variations between the two.

Example 4 In Example 1, 2 parts of MS-cyan-VPl were replaced with MS-
A clear magenta image was obtained when the same procedure as in Example 1 was carried out except that the magenta VPo was changed to 9 parts.

Comparative Example 1 A photoreceptor of Comparative Example 1 was prepared in the same manner as in Example 3, except that the sensitizer had the following cyanine structure.

The absorption spectrum of this sensitizer is shown in FIG.

(Evaluation) While heating this photoreceptor to 50° C., it was exposed imagewise to a 780 nm semiconductor laser (output 30 mW) with a dot diameter of 25 μm×25 μm at a speed of 40 μsec/dot.

After peeling off the acetate film, it was placed on a receiver in the same manner as in Example 1, and the heat-diffusible dye was transferred under the conditions of 110° C. and 30 kg/cm2, and an image was formed on the receiver. The fog density was high. Also,
It has been difficult to obtain consistent image quality due to variations in the oscillation wavelength due to variations between lots of semiconductor lasers.

[Effects of the Invention] As described above, the present invention provides an excellent photopolymerizable photoreceptor and image forming method that can be recorded with a semiconductor laser and that can provide stable, high-quality images. Further, the photoreceptor of the present invention can be manufactured only by coating, and is inexpensive.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of one example of the photopolymerizable photoreceptor of the present invention, and FIG.
The figure is a process diagram showing one example of the image forming method of the present invention, FIG. 3 is a diagram showing the absorption spectrum of the sensitizer used in Example 3,
FIG. 4 is a diagram showing the absorption spectrum of the sensitizer used in Comparative Example 1. 1: Support 2: Color material layer 3: Polymer layer 4: Protective layer 5: Cured part 10: Image receptor 11: Image receiving layer 12: Dye image

Claims (1)

[Claims] 1. Semiconductor laser-sensitive photopolymerization sensitizer, polymerization initiator,
A photopolymerizable photoreceptor characterized by containing a reactive binder and a heat-diffusible dye. 2. Claim 1, characterized in that it has a coloring material layer containing a heat-diffusible dye, and a polymerization layer containing a semiconductor laser-sensitive photopolymerization sensitizer, a polymerization initiator, and a reactive binder.
The photopolymerizable photoreceptor described in . 3. After imagewise exposing the photopolymerizable photoreceptor according to claim 1 with a semiconductor laser, the photoreceptor is placed on an image receptor and heated to transfer the thermally diffusible dye in the unexposed area of the image to the image receptor. An image forming method characterized by: