JP2000338652A - Image forming material and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image forming material having high resolution and high sensitivity and capable of confirming an image after it is imagewise exposed. SOLUTION: The image forming material has a layer containing a material which converts light to heat and a layer containing fine polymer particles on the substrate. The material which converts light to heat is one that is thermally decomposed at <=200 deg.C and the transmission absorbance of the layer containing the material which converts light to heat is 0.2-2 to light for image recording. The image forming material is imagewise exposed with light having a wavelength and intensity at which the absorbance of the layer containing the material which converts light to heat satisfies the expressing (transmission absorbance after exposure with 300 mJ/cm2)/(transmission absorbance before exposure)<=0.5.

Description

DETAILED DESCRIPTION OF THE INVENTION

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BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming material for recording an image by converting light into heat and an image forming method using the same.

[0002]

2. Description of the Related Art Conventionally, there are many known materials that convert light energy into heat energy by using a substance that converts light into heat (light-to-heat conversion material) and heat-seal high molecular polymer particles to form an image. However, as the light-to-heat conversion material, a substance having good heat stability such as carbon black was usually used. However, when these light-to-heat conversion materials are used, sensitivity can be increased by using a material having a large light-to-heat conversion amount, that is, a material having a large absorbance, but the resolution is reduced, while a light-to-heat conversion amount is small, that is, a light absorption amount is small. However, there is a problem that the resolution is improved by using, but the sensitivity is lowered.

Japanese Patent Application Laid-Open No. 9-12387 discloses that light energy is converted into heat energy by a light-to-heat conversion material.
A technology for forming an image by heat-sealing high-molecular polymer fine particles has been disclosed, and there is also a general description of the material for the light-to-heat conversion material, but there is no description about the thermal decomposition property or the absorbance of the recording light. Absent.

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SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming material having high resolution and high sensitivity. Other objects will be apparent from the following description.

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The constitution of the present invention which achieves the above object of the present invention is as follows.

(1) In an image forming material having a layer containing a substance that converts light into heat and a layer containing polymer fine particles on a support, the substance that converts light into heat is heated at 200 ° C. or lower. An image forming material, which is a substance that decomposes.

(2) In an image forming material having a layer containing a substance that converts light into heat and a layer containing polymer fine particles on a support, the substance that converts light into heat is heated to 200 ° C. or less. An image forming material, characterized in that a layer containing a substance that decomposes and converts light into heat has an image recording light transmission absorbance of 0.2 or more and 2 or less.

(3) An image forming method using an image forming material having a layer containing a substance that converts light to heat and a layer containing high molecular weight polymer particles on a support, comprising a substance that converts the light into heat. An image forming method, wherein image exposure is performed with light having a wavelength and intensity such that the absorbance of the layer is (transmission absorbance after exposure of 300 mj / cm ² ) / (transmission absorbance before exposure) ≦ 0.5.

(4) An image forming method comprising subjecting the image forming material according to (1) or (2) to image exposure with an energy amount of 200 mj / cm ² or more.

According to the present invention, by using a photothermal conversion material which decomposes to a specific temperature, an image forming material having both good resolution and sensitivity can be obtained, and in addition, a latent image can be visualized after image exposure. Now you can check the image before printing.

Hereinafter, the present invention will be described in detail.

The polymer particles used in the present invention will be described. Preferred polymer fine particles in the embodiment of the present invention are thermoplastic hydrophobic polymer fine particles. Although there is no specific upper limit for the softening temperature of the thermoplastic hydrophobic polymer particles, the temperature is preferably lower than the decomposition temperature of the polymer polymer particles.

Specific examples of the polymer constituting the polymer particles include polyolefins such as polyethylene, polypropylene and ethylene-butene copolymer, polybutadiene, polyisoprene, ethylene-butadiene copolymer and the like. Diene (co) polymers, styrene
Synthetic rubbers such as butadiene copolymer, methyl methacrylate-butadiene copolymer, acrylonitrile-butadiene copolymer, polymethyl methacrylate, methyl methacrylate- (2-ethylhexyl acrylate) copolymer, methyl methacrylate-methacrylic acid copolymer ,
Methyl acrylate- (N-methylolacrylamide) copolymer, (meth) acrylic acid ester such as polyacrylonitrile, (meth) acrylic acid (co) polymer, polyvinyl acetate, vinyl acetate-vinyl propionate copolymer, acetic acid Examples include vinyl ester (co) polymers such as vinyl-ethylene copolymers, vinyl acetate- (2-ethylhexyl acrylate) copolymers, polyvinyl chloride, polyvinylidene chloride, polystyrene, and the like, and copolymers thereof. Of these, (meth) acrylates,
(Meth) acrylic acid (co) polymer, vinyl ester (co) polymer, polystyrene, and synthetic rubbers are preferably used.

The weight average molecular weight (Mw) of the high molecular weight polymer is preferably in the range of 5,000 to 1,000,000.

When the high molecular weight polymer contains a functional group having an acid value, it may be an ionomer resin having a structure in which a part or all of the functional groups are crosslinked and integrated through polyvalent metal ions. . When the high molecular weight polymer particles are non-aqueous dispersible fine particles, it is preferable to use high molecular weight polymer particles finely crosslinked by covalent bond or ionic bond.

The fine polymer particles may be composed of a polymer polymerized by any known method such as an emulsion polymerization method, a suspension polymerization method, a solution polymerization method, and a gas phase polymerization method. As a method of forming fine particles of a polymer polymerized by a solution polymerization method or a gas phase polymerization method, a method of spraying a solution in an organic solvent of the high molecular polymer in an inert gas, drying and forming fine particles, Dissolve the polymer in a water-immiscible organic solvent,
The solution may be dispersed in water or an aqueous medium, and the organic solvent may be distilled off to form fine particles. In any method, a dispersant or a stabilizer may be used as a dispersant or a stabilizer during polymerization or micronization, if necessary, as a surfactant such as sodium lauryl sulfate, sodium dodecylbenzenesulfonate, or polyethylene glycol, or a water-soluble resin such as polyvinyl alcohol. May be used.

The polymer fine particles are preferably used in the form of a dispersion dispersed in a dispersion medium, and are preferably an aqueous dispersion.

The particle size of the high molecular polymer particles is 0.005 to 0.005.
It preferably has a particle size of 2 μm, and the amount of the polymer particles contained in the layer containing the polymer particles is preferably at least 30% by weight, more preferably at least 45% by weight, and most preferably At least 60
% By weight.

In the present invention, in order to prevent the particles from fusing at the time of drying and to maintain the layer structure,
Preferably, a particle adhesion inhibitor is included. The particle adhesion inhibitor is appropriately selected from those which dissolve in the coating solvent of the layer containing the high molecular polymer fine particles and dissolve or swell in the developer according to the purpose of the image forming material. When the polymer fine particles are water-dispersible, the particle adhesion inhibitor preferably used is a hydrophilic particle adhesion inhibitor.

Specifically, water-soluble (co) polymers such as synthetic homo or copolymers such as polyvinyl alcohol, poly (meth) acrylic acid, poly (meth) acrylamide, polyhydroxyethyl (meth) acrylate, polyvinyl methyl ether Alternatively, natural binders such as gelatin, polysaccharides such as dextran, pullulan, cellulose, gum arabic, arginic acid, colloidal silica of hydrophilic inorganic fine particles, and glycerin of polyhydric alcohol can be used.

The particle adhesion inhibitor may be a water-insoluble, alkali-soluble or swellable resin having a phenolic hydroxy group and / or a carboxyl group. Among these, those which can be removed with a developer containing water or water having a pH of 3 to 11 as a main component are preferably used. When the image forming material is used for producing a printing plate, it is further preferable that the material can be removed with a fountain solution.

When the high molecular polymer fine particles are non-aqueous dispersible fine particles, the particle adhesion preventing agent preferably used is an organic solvent-soluble particle adhesion preventing agent. Among them, those that are soluble in relatively low-polarity solvents such as hydrocarbon solvents are more preferable. Specifically, low molecular weight polyethylene, rosin-modified phenol resin, petroleum resin, alkyd resin and the like are used. When an adhesion inhibitor containing an ethylenically unsaturated double bond is used, it is preferable to use a polymerization inhibitor such as hydroquinone or p-methoxyphenol. Preferably, the particle adhesion inhibitor is uncrosslinked or only slightly crosslinked. In the case where the layer containing the high molecular weight polymer particles contains a liquid particle adhesion inhibitor, for example, a peelable anti-drying film is formed to enhance the storage stability of the printing plate prepared from the image forming material. May be.

As the substance capable of converting light into heat (hereinafter referred to as "photothermal conversion material") used in the present invention, a substance capable of absorbing actinic rays and converting it into heat can be used. Among such substances, it is preferable to use a substance that absorbs light having a wavelength of 700 nm or more and 1500 nm or less. For example, an infrared absorbing dye, carbon black, magnetic powder, or the like having an absorption wavelength of 700 nm or more is preferably used. preferable. Particularly preferred infrared absorbing dyes have a maximum absorption at 700 nm or more and 1200 nm or less, and have a peak molar extinction coefficient ε of 10
It is a dye of 000 or more.

Examples of the infrared absorbing dyes include cyanine dyes, squarium dyes, croconium dyes, azurenium dyes, phthalocyanine dyes, naphthalocyanine dyes, polymethine dyes, naphthoquinone dyes, thiopyrylium dyes, and dithiol metal dyes. Examples include complex dyes, anthraquino dyes, indoaniline metal complex dyes, and intermolecular CT dyes. Further, as the infrared absorbing dye, JP-A-63-139191 and JP-A-64-3354.
No. 7, JP-A-1-160683 and 1-280750
Nos. 1-293342, 2-2074, 3-
No. 26593, No. 3-30991, No. 3-34891
No. 3-36093, No. 3-36094, No. 3-
No. 36095, No. 3-42281, No. 3-10347
No. 6 and the like.

In the present invention, a cyanine dye represented by the following general formula (1) or (2) is particularly preferred as the photothermal conversion material.

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In the formula, Z ₁ and Z ₂ each represent a sulfur atom, a selenium atom or an oxygen atom, and X ₁ and X ₂ each form an optionally substituted benzo-fused ring or naphtho-fused ring. And R ₃ and R ₄ each represent a substituent, and one of R ₃ and R ₄ has an anionic dissociable group. R ₅ , R ₆ , R ₇ and R ₈ each represent an alkyl group having 1 to 3 carbon atoms, a hydrogen atom or a halogen atom. L represents a chain of conjugated bonds having 5 to 13 carbon atoms.

The cyanine dye represented by the general formula (1) or (2) includes those forming a cation and having a counter anion. In this case, as the counter anion, Cl ^{-,
_{Br -, ClO 4 -, BF}} 4 -, include alkylboron arsenide of t- butyl triphenyl borate arsenide.

In the general formulas (1) and (2), the number of carbon atoms (n) in the chain of conjugated bonds represented by L is determined when a laser emitting infrared light is used as a light source for image exposure. It is preferable to select an effective value according to the transmission wavelength of the light. For example, Y at an emission wavelength of 1060 nm
When an AG laser is used, n is preferably 9 to 13. The conjugate bond may have an arbitrary substituent, and the conjugate bond may form a ring with a plurality of substituents. Further, the ring represented by X ₁ and the ring represented by X ₂ can have an arbitrary substituent. Halogen atom as the substituent, an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, (the M hydrogen atom or an alkali metal atom) -SO ₃ M and -COOM is a group selected from the preferred .

R ₃ and R ₄ are each an optional substituent,
Preferably, an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms;-(CH ₂ ) _n -O-)
_{k - (CH 2) m OR} (n and m are each an integer of 1 to 3, k
Represents 0 or 1, and R represents an alkyl group having 1 to 5 carbon atoms. One of R ₃ and R ₄ is —R—SO ₃ M and the other is —
R—SO ₃ ⁻ (R represents an alkyl group having 1 to 5 carbon atoms, M represents an alkali metal atom); or one of R ₃ and R ₄ represents —
R-COOM other hand is -R-COO ^- (R is an alkyl group having 1 to 5 carbon atoms, M represents an alkali metal atom.)
It is. R ₃ and R ₄ are, in terms of sensitivity and developability, R ₃
And one is the -R-SO ₃ of R ₄ ^- or -R-COO ^-,
It is preferred the other is the -R-SO ₃ M or -R-COOM.

In the present invention, when a semiconductor laser is used as a light source for image exposure, the infrared-absorbing dye used as the photothermal conversion material is YA-900 nm.
When a G laser is used, it is preferable that the compound exhibit an absorption peak at 900 to 1200 nm and have a molar absorption coefficient of ε> 1 × 10 ⁵ . Further, one or more dyes belonging to both systems may be used in combination.

Typical specific examples of the infrared absorbing dye preferably used in the present invention are shown below, but the present invention is not limited thereto.

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These dyes can be synthesized by a known method, but the following commercially available products can also be used.

Nippon Kayaku: IR750 (anthraquinone type); IR002, IR003 (aluminum type);
R820 (polymethine type); IRG022, IRG03
3 (diimmonium-based); CY-2, CY-4, CY-
9, CY-10, CY-17, CY-20, Mitsui Toatsu:
KIR103, SIR103 (cyanine); KIR1
01, SIR114 (anthraquinone); PA100
1, PA1005, PA1006, SIR128 (metal complex type), Dainippon Ink and Chemicals: Fastogenblue
e8120, Midori Kagaku: MIR-101, 1011,
1021 and others, and other companies such as Nippon Kogaku Dye, Sumitomo Chemical, Fuji Photo Film, and the like.

In the present invention, the added amount of the photothermal conversion material is
Preferably, it is 0.5 to 10% by weight, more preferably 1 to 5% by weight, in the layer containing the photothermal conversion material.

As the photothermal conversion material used in the first, second or fourth aspect of the present invention, a substance which irreversibly decomposes at a temperature of 200 ° C. or lower is selected from the above materials.

In the measurement of the decomposition temperature of the photothermal conversion material according to the present invention, first, 0.1 g of a substance to be measured is prepared, and 5 ° C./mi from room temperature to 200 ° C., which is the ultimate temperature, in air.
n at a rate of n.
After cooling to room temperature at a rate of min, the decomposition rate was measured by spectroscopic analysis, and those having a decomposition rate of less than 50% were defined as "decomposition temperature of 200 ° C or higher". The final temperature was lowered by 1 ° C. in steps of 1 ° C. to a temperature at which the decomposition rate was less than 50% for the same sample, and the same temperature increase, temperature holding, cooling operation, and measurement were repeated, and “decomposition rate was 50%.
% Is defined as the decomposition temperature.

In the invention according to claim 1, 2 or 4,
The light-to-heat conversion material is most preferably added to the layer containing the high molecular weight polymer particles, but it is also possible to adopt a mode in which part or all of the light-to-heat conversion material is included in the adjacent layer. The adjacent layer may be a layer containing polymer fine particles or a layer not containing polymer fine particles.

The coating solvent for the layer containing the fine polymer particles can be dispersed without dissolving the fine polymer particles.
A solvent that can be dried at a relatively low temperature of 0 ° C. or less is selected.
When a particle adhesion inhibitor or a light-to-heat conversion material is added to the layer containing the polymer particles, it is preferable that these can be dissolved or dispersed.

The support used for the image forming material of the present invention is not particularly limited. However, when the present invention is used for an offset printing plate material, a support capable of repelling a printing ink by retaining its own properties or water. For example, a support having an ink repellent layer made of silicone or the like, or a support having a hydrophilic layer or a hydrophilic surface for holding a fountain solution is used. It is preferable to use a support. As the hydrophilic support, paper, plastic, plate-like material such as metal can be used, and there is no limitation, but coated paper,
A plastic sheet whose surface has been rendered hydrophilic by a treatment such as corona discharge, or an aluminum plate whose surface has been subjected to a surface treatment such as graining or anodizing can be used. When a hydrophilic layer is provided on the support to form a hydrophilic support, an intermediate layer such as an adhesive layer may be provided between the support and the hydrophilic layer.

In the present invention, the image-forming material is used as an image-forming material for recording an image by converting light into heat, and the image recording is preferably performed by laser scanning exposure. It is more preferable to use a laser that operates in a wavelength region of 700 to 1500 nm. Most preferred are laser diodes that emit in the near infrared.

In the present invention, the image-forming material may be developed with an appropriate developer after image recording and before being mounted on a printing press, or may be performed on a printing press after being mounted on the printing press. Development may be performed manually or automatically. The development may be carried out not only by dissolving and redispersing the layer containing the high molecular weight polymer particles with the developer, but also by using swelling peeling or adhesive peeling.

The development is appropriately selected according to the constitution of the image forming material. When the layer containing the high molecular weight polymer particles contains a particle adhesion inhibitor, a material capable of dissolving or swelling the particle adhesion inhibitor is selected. Is preferably performed.

In an image forming material using water or an aqueous solvent as a dispersion medium or a coating solvent for high molecular weight polymer particles, it is preferable to use water or a developer containing water as a main component. Those in the range are more preferred. When used as a lithographic printing plate, it is most preferable that the fountain solution is the same as the developer, for example, the fountain solution is the developer.

It is preferable to use a developer containing an organic solvent in an image forming material in which an organic solvent that is not miscible with water is used as a dispersion medium or a coating solvent for the high-molecular polymer fine particles. The ink and the developer may be the same.

In the invention according to claim 2 or 4, the layer containing the photothermal conversion material of the image forming material has an image recording light transmission absorbance of 0.2 or more and 2 or less. This image recording light transmission absorbance is measured by preparing a measurement sample in the same manner as in the preparation of the image forming material except that the support is changed to a support having an absorbance to the image recording light of 1 or less, and a spectrophotometer Measure using At this time, the measurement is performed by placing a support having an absorbance of 1 or less for the image recording light used for preparing the measurement sample on the reference side to be compared.

The change in absorbance before and after image exposure of the layer containing the photothermal conversion material according to the third aspect of the present invention is also carried out by measuring the absorbance before and after overall exposure using a sample prepared in the same manner as described above.

According to the third aspect of the present invention, in the image forming method using an image forming material having a layer containing a photothermal conversion material and a layer containing polymer fine particles on a support, the layer containing the photothermal conversion material is provided. Is exposed to light having a wavelength and intensity at which the absorbance of (a transmission absorbance after exposure of 300 mj / cm ² ) / (transmission absorbance before exposure) ≦ 0.5, thereby exposing the unexposed portion before and after the image exposure. There is a clear difference in image density between the parts, so that the image can be checked before printing, and the best sensitivity and resolution can be obtained.

As the light-to-heat conversion material used for such an image forming material, the light-to-heat conversion material of the first aspect of the present invention or other materials may be used. What is used for the invention according to claim 1 can be used.

[0064]

EXAMPLES (Synthesis of Dispersion Stabilizer) Synthesis Example 1 50 parts by weight of n-octane was charged into a reactor equipped with a thermometer, a stirrer, a reflux condenser and a nitrogen gas inlet tube, and then n-octane was charged into another container. Butyl methacrylate (nBMA) 50
% By weight, i-butyl methacrylate (iBMA) 30% by weight, 2-ethylhexyl acrylate (EHA) 20
400 parts by weight of a monomer mixture consisting of 100% by weight was prepared, and 200 parts by weight of the mixture was charged into a reactor. After the inside of the reactor was replaced with nitrogen, the temperature was raised to 100 ° C., and 2,2′-azobis-
0.1 parts by weight of i-butyl nitrile (AIBN) was added, and the mixture was kept at the same temperature for 30 minutes. And the remaining monomer mixture 2
00 parts by weight, 50 parts by weight of n-octane and AIBN
A mixture consisting of 0.5 parts by weight was successively added dropwise over 2 hours. Then, after adding 3 parts by weight of AIBN, the mixture was kept at the same temperature for 3 hours, and then 500 parts by weight of acetonitrile was added thereto, followed by cooling. Obtained.

The non-volatile content of this solution was 40 wt%, and the weight average molecular weight of the dispersion stabilizer was about 180,000. (Production of High Molecular Polymer Particle Dispersion) Production Example 1 A 1000 ml four-necked flask was provided with a stirrer, a thermometer, a dropping funnel, a nitrogen inlet tube, and a reflux condenser, and nitrogen gas was introduced to perform deoxygenation. 350 ml of distilled water was added, and the mixture was heated until the internal temperature reached 80 ° C. 3.5 g of sodium lauryl sulfate and 1.5 g of polyvinyl alcohol (tensile strength = 80%, number average molecular weight = 9000) were added as a dispersant, and 0.45 g of ammonium persulfate was further used as an initiator.
Was added, and then 65 g of methyl methacrylate and 25 g of 2-ethylhexyl acrylate were added dropwise using a dropping funnel over about 1 hour. After continuing the reaction for 5 hours after the completion of the dropwise addition, unreacted monomers were removed by steam distillation. Thereafter, the mixture was cooled and adjusted to pH 6 with aqueous ammonia, and finally pure water was added so that the nonvolatile content was 15% by weight, to obtain a polymer polymer fine particle dispersion liquid-1. The average particle size of the polymer particle dispersion liquid-1 was 150 nm.

Production Example 2 The polymer fine particle dispersion-1 obtained in Production Example 1 was added to 100
The obtained polymer was dried at 5 ° C. under reduced pressure to obtain 15 g of polymer powder. After adding 3.75 g of the dispersion stabilizer solution-1 obtained in Synthesis Example 1, 60 g of acetonitrile and 21.25 g of methanol were added thereto to obtain a polymer polymer fine particle dispersion liquid-2.

Comparative Example 1 An aluminum plate (material: 1050, tempered H16) having a thickness of 0.3 mm was immersed in a 10% aqueous sodium hydroxide solution kept at 85 ° C., and subjected to a degreasing treatment for 5 seconds. Washed with water. The degreased aluminum plate was immersed in a 10% aqueous sulfuric acid solution maintained at 25 ° C. for 30 seconds, neutralized, and then washed with water. Next, an abrasive slurry (alumina, # 400, 18% by weight) was used for the aluminum plate,
The surface was roughened by pressing a rotating nylon brush against the support. The surface was roughened by pressing the brush against the support at 15 mm and passing the brush a predetermined number of times at a line speed of 5 m / min. The rotation direction of the brush was opposite to the running direction of the support, and the rotation speed was 400 rotations per minute. Then, the substrate was immersed in a 1% aqueous sodium hydroxide solution kept at 50 ° C. and etched so as to have a dissolution amount of 35 g / m ² , and then immersed in a 10% aqueous sulfuric acid solution kept at 25 ° C. for 10 seconds. After the neutralization treatment, it was washed with water. Then, in a 20% sulfuric acid aqueous solution, at a temperature of 25 ° C. and a current density of 2 A
Anodizing treatment was performed for 1 minute under the condition of / dm ² . Thereafter, the substrate was immersed in a 0.1% aqueous solution of ammonium acetate kept at 80 ° C. for 30 seconds, subjected to sealing treatment, and dried at 80 ° C. for 5 minutes. The heat-sensitive image forming layer composition-1 having the composition was used as a dispersion, and applied so that the dry coating amount was 1.6 g / m ² , and 55 ° C.
For 20 minutes to obtain image forming material-1.

Heat-Sensitive Image-Forming Layer Composition-1 Polymer Polymer Fine Particle Dispersion-1 50.00 parts by weight MA-100 (carbon black, manufactured by Mitsubishi Chemical Corporation, thermal decomposition temperature> 200 ° C.) 0.95 Parts by weight Glycerin 0.75 parts by weight KL05 (80% saponified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Co., Ltd.) 0.75 parts by weight Pure water 47.55 parts by weight The obtained image forming material-1 has energy on the image surface. Image exposure was performed using a semiconductor laser light source (emission wavelength: 830 nm, spot diameter: 6.35 μm) having an output of 100 mW while changing the amount between 250 and 480 mJ / cm ² in steps of 10 mJ.

Although it was difficult to visually confirm the obtained latent image of the image-exposed image forming material, it was mounted on a printing machine (DAIYA, manufactured by Mitsubishi Heavy Industries, Ltd.) without performing development processing. Printing was started as it was. At this time, offset ink Hi-Echo Red (M) (manufactured by Toyo Ink Mfg. Co., Ltd.) was used as the ink, and SG-51 (manufactured by Tokyo Ink Co., Ltd.) was diluted to 2% by weight with tap water as the dampening solution. It was used.

Shortly after the start of printing, the development of the image forming material was completed, and a good printed matter was obtained. Although the image resolution of the printed matter was 4000 dpi, an image exposure energy amount of 470 mJ / cm ² was necessary to obtain a printable image.

The heat-sensitive image-forming layer composition-1 was coated with 100 μm
Polyethylene terephthalate film (Lumilar T-6)
0, manufactured by Toray Industries, Inc.
A sample for measuring absorbance was obtained by coating and drying in the same manner as described above, and the transmission absorbance at 830 nm of the heat-sensitive image forming layer was measured. The absorbance was 0.70. Further, the entire surface of the sample was exposed to 300 mJ / cm ² using the semiconductor laser light source used for the image exposure,
The absorbance at 30 nm was measured to be 0.68, which was 95% of the absorbance before exposure.

Comparative Example 2 The amount of MA-100 in the heat-sensitive image forming layer composition-1 was changed to 1.
An image-forming material-2 was obtained in the same manner as in Comparative Example 1 except that the heat-sensitive image-forming layer composition-2 was changed to 89 parts by weight.
Similarly, image exposure and printing were performed.

As in Comparative Example 1, it was difficult to visually check the latent image of the image forming material.
In No. ² , a printable image could be obtained with an image exposure energy of 370 mJ / cm ² . However, the image resolution of the printed matter has been reduced to 2000 dpi.

The absorbance of the thermal image forming layer composition-2 before and after exposure to 300 mJ / cm ^{2 over the} entire surface was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 1.3.
After exposure, it had an absorbance of 1.26 and 95% of that before exposure.

Comparative Example 3 An image-forming material-3 was obtained in the same manner as in Comparative Example 1, except that the heat-sensitive image-forming layer composition-1 was changed to the following heat-sensitive image-forming layer composition-3. Exposure and printing were performed.

Thermosensitive image forming layer composition-3 High molecular polymer fine particle dispersion-2 50.00 parts by weight Kayasorb CY-2 0.15 parts by weight (infrared absorbent, Nippon Kayaku Co., Ltd., thermal decomposition Glycerin 1.00 parts by weight KL05 (80% saponified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Co., Ltd.) 0.50 parts by weight Acetonitrile 28.35 parts by weight Methanol 20.00 parts by weight As in Comparative Example 1, Although it was difficult to visually check the latent image of the image forming material, the development of the image forming material was completed shortly after the start of printing, and a good printed matter was obtained. Although the image resolution of the printed matter was 4000 dpi, an image exposure energy amount of 450 mJ / cm ² was necessary to obtain a printable image.

For the thermal image-forming layer composition-3, the absorbance before and after exposure to the entire surface of 300 mJ / cm ² was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 0.6.
5. After exposure, it had an absorbance of 0.41 and 63% of the absorbance before exposure.

Comparative Example 4 The amount of CY-2 in the heat-sensitive image forming layer composition-2 was 0.30
An image forming material-4 was obtained in the same manner as in Comparative Example 3 except that the heat-sensitive image forming layer composition-4 was changed to parts by weight, and image exposure and printing were performed in the same manner.

As in Comparative Example 1, it was difficult to visually check the latent image of the image forming material.
In No. 4, a printable image could be obtained with an image exposure energy of 360 mJ / cm ² . However, the image resolution of the printed matter has been reduced to 2000 dpi.

For the thermal image-forming layer composition-3, the absorbance before and after exposure to 300 mJ / cm ^{2 of the} entire surface was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 1.2.
2. It had an absorbance of 0.67 after exposure and 55% of the absorbance before exposure.

Comparative Example 5 Kayasorb CY of heat-sensitive image forming layer composition-3
-2 is Kayasorb CY-4 (infrared absorbent, manufactured by Nippon Kayaku Co., Ltd., thermal decomposition temperature> 200 ° C.), and the amount of addition is 0.30 part by weight.
Image forming material-5 in the same manner as in Comparative Example 3 except that
And subjected to image exposure and printing in the same manner.

As in Comparative Example 1, it was difficult to visually check the latent image of the image forming material.
In No. 4, a printable image could be obtained with an image exposure energy of 360 mJ / cm ² . However, the image resolution of the printed matter has been reduced to 2000 dpi.

For the thermal image-forming layer composition-5, the absorbance before and after exposure to 300 mJ / cm ^{2 of the} entire surface was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 1.2.
6. It had an absorbance of 0.68 after exposure and 54% of the absorbance before exposure.

Example 1 Kayasorb CY of heat-sensitive image forming layer composition-3
Image was formed in the same manner as in Comparative Example 3 except that the thermosensitive image-forming layer composition-6 was changed to Kayasorb CY-9 (infrared absorbent, manufactured by Nippon Kayaku Co., Ltd., thermal decomposition temperature = 193 ° C.). Forming material-6 was obtained, and image exposure and printing were performed in the same manner.

In this image forming material-6, since the exposed portion faded and the latent image of the image forming material was visualized, the image could be confirmed before printing. Also, 380 mJ / cm ²
A printable image could be obtained with the image exposure energy amount of, and the image resolution of the printed matter was as high as 4000 dpi.

For the thermal image-forming layer composition-6, the absorbance before and after exposure to the entire surface of 300 mJ / cm ² was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 0.61.
However, the absorbance was 0.18 after exposure and 30% before exposure.

Example 2 Kayasorbu C of heat-sensitive image forming layer composition-3
Y-2 is replaced with Kayasorb CY-9 (infrared absorbent,
Thermal decomposition image forming layer composition in which the thermal decomposition temperature is 193 ° C., manufactured by Nippon Kayaku Co., Ltd., and the added amount is 0.30 part by weight.
Image-forming material in the same manner as in Comparative Example 3 except that Sample No. 7 was used.
7 and image exposure and printing were performed in the same manner. In this image forming material-7, similarly to the image forming material-6, the exposed portion was discolored, the latent image of the image forming material was visualized, and the image could be confirmed before printing. In addition, a printable image could be obtained with an image exposure energy of 290 mJ / cm ² , and the printed matter had a high image resolution of 4000 dpi.

For the thermal image-forming layer composition-7, the absorbance before and after exposure to the entire surface of 300 mJ / cm ² was measured in the same manner as in Comparative Example 1. The absorbance before the exposure was 1.28.
However, the absorbance decreased to 0.31 after exposure to 24% before exposure.

Example 3 Kayasorb CY of heat-sensitive image forming layer composition-3
-2 is Kayasorb CY-9 (infrared absorbent, manufactured by Nippon Kayaku Co., Ltd., thermal decomposition temperature = 193 ° C.), and the amount of addition thereof is 0.40 part by weight.
Image forming material-8 in the same manner as in Comparative Example 3 except that
And subjected to image exposure and printing in the same manner.

This image forming material-8 was also used as image forming material-6.
Similarly, the exposed portion faded, the latent image of the image forming material was visualized, and the image could be confirmed before printing. Also, 29
A printable image can be obtained with an image exposure energy of 0 mJ / cm ² , and the image resolution of the printed matter is 40.
It had a high resolution of 00 dpi.

For the thermal image-forming layer composition-8, the absorbance before and after exposure to 300 mJ / cm ^{2 of the} entire surface was measured in the same manner as in Comparative Example 1, and the absorbance before exposure was 1.60.
However, the absorbance was reduced to 0.34 after exposure to 21% before exposure.

Example 4 Kayasorb CY of heat-sensitive image forming layer composition-3
-2 was changed to Kayasorb CY-9 (infrared absorbing agent, manufactured by Nippon Kayaku Co., Ltd., thermal decomposition temperature = 193 ° C.), and the amount of addition was 0.65 parts by weight.
Image forming material in the same manner as in Comparative Example 3 except that No. 9 was used.
9 was produced, and image exposure and printing were performed in the same manner.

This image forming material-9 is also image forming material-6.
Similarly to the above, the exposed portion was discolored, the image forming material was visualized, and the image could be confirmed before printing. Also, 29
A printable image can be obtained with an image exposure energy of 0 mJ / cm ² , and the image resolution of the printed matter is 30.
It had a high resolution of 00 dpi.

The thermal image-forming layer composition-9 was also measured for absorbance before and after exposure to 300 mJ / cm ² by the same method as in Comparative Example 1.
20, but 0.53 after exposure and 24% before exposure.
Absorbance decreased.

Example 5 Kayasorb CY of heat-sensitive image forming layer composition-3
-2 as Kayasorb CY-10 (infrared absorber,
An image forming material-10 was obtained in the same manner as in Comparative Example 3, except that the thermal image forming layer composition-10 was changed to a thermal decomposition temperature of 200 ° C., manufactured by Nippon Kayaku Co., Ltd. Printing was done.

This image forming material-10 is also an image forming material
Similarly to 6, the latent image on the image forming material was visualized by fading of the exposed portion, and the image could be confirmed before printing. Also, 3
A printable image can be obtained with an image exposure energy of 70 mJ / cm ² , and the image resolution of the printed matter is 4
It had a high resolution of 000 dpi.

For the thermal image-forming layer composition-10, the absorbance before and after exposure to 300 mJ / cm ^{2 of the} entire surface was measured in the same manner as in Comparative Example 1. The absorbance before exposure was 0.6.
7, but the absorbance decreased to 0.21 after exposure to 31% before exposure.

Example 6 Kayasorb CY of heat-sensitive image forming layer composition-3
-2 as Kayasorb CY-10 (infrared absorber,
(Thermal decomposition temperature = 200 ° C., manufactured by Nippon Kayaku Co., Ltd.), and the amount of addition is 0.30 part by weight.
An image forming material-11 was obtained in the same manner as in Comparative Example 3 except that No.11 was used, and image exposure and printing were performed in the same manner.

This image forming material-11 is also an image forming material
Similarly to 6, the latent image on the image forming material was visualized by fading of the exposed portion, and the image could be confirmed before printing. Also, 2
A printable image can be obtained with an image exposure energy of 80 mJ / cm ² , and the image resolution of the printed matter is 4
It had a high resolution of 000 dpi.

The thermal image-forming layer composition-11 was also measured for absorbance before and after exposure to 300 mJ / cm ^{2 over the} entire surface in the same manner as in Comparative Example 1. The absorbance before exposure was 1.3.
2, but the absorbance decreased to 0.34 after exposure to 26% before exposure.

Example 7 An image-forming material-12 was obtained in the same manner as in Comparative Example 1, except that the heat-sensitive image-forming layer composition-1 was changed to the following heat-sensitive image-forming layer composition-12. Exposure and printing were performed.

Thermosensitive image forming layer composition-12 High molecular polymer fine particle dispersion-1 50.00 parts by weight Kayasorb CY-17 0.30 parts by weight (infrared absorbent, manufactured by Nippon Kayaku Co., Ltd., pyrolysis Glycerin 1.00 parts by weight KL05 (80% saponified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Co., Ltd.) 0.50 parts by weight Pure water 48.35 parts by weight This image forming material-12 is also an image forming material. Similarly to -6, the exposed portion was discolored and the latent image of the image forming material was visualized, and the image could be confirmed before printing. In addition, 350mJ / c
It is possible to obtain an image that can be printed with an image exposure energy of m ² , and the image resolution of the printed matter is 4000 dpi.
Had a high resolution.

[0103] Measurement of the absorbance before and after the 300 mJ / cm ² overall exposure in the same manner in Comparative Example 1 also image formation layer composition 12, the absorbance before exposure 0.9
Although it was 0, the absorbance decreased to 0.19 after exposure and 21% before exposure.

The results of Comparative Examples 1 to 5 and Examples 1 to 7 are shown in Table 1 below.

[0105]

[Table 1]

[0106]

According to the present invention, there is provided an image forming material having high resolution and high sensitivity, wherein an image can be confirmed after image exposure.

Claims (4)

[Claims] 1. An image forming material having a layer containing a substance that converts light into heat and a layer containing polymer fine particles on a support, wherein the substance that converts light into heat is thermally decomposed at 200 ° C. or lower. An image forming material characterized in that the material is 2. An image forming material having a layer containing a substance that converts light into heat and a layer containing polymer fine particles on a support, wherein the substance that converts light into heat is thermally decomposed at 200 ° C. or lower. An image forming material, characterized in that the layer containing a substance that converts light into heat has an image recording light transmission absorbance of 0.2 or more and 2 or less. 3. An image forming method using an image forming material having a layer containing a substance that converts light into heat and a layer containing polymer fine particles on a support, wherein the layer containing a substance that converts the light into heat is provided. An image forming method, wherein image exposure is carried out with light having a wavelength and intensity such that the absorbance of (Absorbance after exposure of 300 mj / cm ² ) / (Absorbance before exposure) ≦ 0.5. 4. The image forming material according to claim 1, wherein
An image forming method, wherein image exposure is performed with an energy amount of 00 mj / cm ² or more.