JPH1124199A - Heat developing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output a hard copy with high throughput even in the case of using an ordinary plug socket as a power source by irradiating photosensitive heat developable recording material after recording a latent image by exposure with developing light and developing the image by photo-thermal conversion. SOLUTION: The photosensitive heat developable recording material A constituted by forming a photosensitive heat developable image forming layer on a supporting body such as a polyethylene terephthalate(PET) film is used for an image recorder 10, where the material A is image-exposed so as to record the latent image, and then the exposed material A is thermally developed so as to develop color, and outputted as the hard copy where the image is formed. Various kinds of recording material of heat developing (heat developing color) type where the image can be recorded by the exposure can be used as the material A used in this developing method. Such material A is thermally developed by the photo-thermal conversion by using the developing light, whereby the hard copy where the image is formed is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a heat development method in image formation using a photosensitive heat development (thermochromic) recording material.

[0002]

2. Description of the Related Art Conventionally, ultrasonic diagnosis, CT diagnosis, MR
Images taken by I diagnosis, X-ray diagnosis and the like are recorded on a silver halide photographic light-sensitive material to form a hard copy. However, while silver halide photographic materials can provide high-quality images, they require wet development processing such as color development, fixing bleaching, and washing with water. There is also a problem that maintenance of the (processor) is troublesome, and it is desired to output a hard copy by an image forming method that does not require a wet developing process.

As an image forming method that does not require wet processing,
Thermal image recording is known. As is well known, the thermal image recording uses a thermal head having a glaze in which heating elements are arranged in one direction (main scanning direction), and presses the glaze against the thermosensitive recording material. The image is recorded on the heat-sensitive recording material by generating heat in each heating element according to the recorded image while relatively moving in the orthogonal direction. The image quality of such thermal recording images has been greatly improved in recent years. Recently, in addition to recording of ultrasonic diagnostic images conventionally used, CT diagnosis, MRI diagnosis,
Use for applications requiring large and high-quality images, such as line diagnosis, is also being studied. However, in terms of recording density and gradation reproducibility, an image formed by exposing a silver halide photographic material with a light beam or the like is also advantageous.

As an image forming method which has solved such problems, attention has been paid to image recording using a photosensitive heat-developable recording material. The photosensitive heat-developable recording material is a recording material that develops a color by exposure and heating, or a recording material that stops developing a color by exposure and develops a color by heating. By forming a latent image and heating the exposed photosensitive material, an exposed portion or a non-exposed portion is colored to obtain a hard copy on which an image is recorded. According to the image recording using such a photosensitive heat development recording material, a high-definition high-quality image using a light beam scanning exposure or the like can be formed without performing a wet development process.

[0005]

The thermal development in image formation using such a photosensitive heat-developable recording material (hereinafter, referred to as a recording material) is usually performed by heating the recording material using a heater or the like. This is done by: As a specific example, a drum including a heater such as a halogen lamp and an endless belt driven by a drum that is wound around the drum for about 2/3 turn are used to rotate the drum.
An example is a method in which a recording material is inserted between a drum and an endless belt, conveyed, and discharged from the opposite end, thereby heating at a predetermined temperature for a predetermined time to perform thermal development.

[0006] The recording material is formed by using a polyethylene terephthalate (PET) film or the like as a support, forming an image forming layer having photosensitivity and heat development (thermochromic), and further forming various layers such as a protective layer if necessary. It is made. In such a recording material, basically, only the image forming layer needs to be heated for color development by thermal development. However, in the heating method using a heater, the support is also heated, that is, the heat is deprived to the support, so that the amount of heat that is originally required for thermal development is required, and efficient thermal development is performed. Can not do. In particular, in medical applications such as those described above, a thick PET film or the like is used as a support in order to obtain the same quality as conventionally used silver halide photographic light-sensitive materials. In order to form a color, it is necessary to apply a large amount of heat compared to the amount of heat originally required for development.

That is, the conventional thermal development is very inefficient in energy, and requires high energy in order to output a hard copy with a high processing capability. In some cases, a normal AC 100 V outlet may not be enough. Occurs.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to form an image using a photosensitive heat-developable recording material and efficiently heat the image-forming layer to perform heat development. It is an object of the present invention to provide a heat developing method with good energy efficiency, capable of outputting a hard copy with high processing capability even when a normal AC 100 V outlet or the like is used as a power supply.

[0009]

In order to achieve the above object, the present invention relates to a thermal development method for forming an image using a photosensitive thermal development recording material, wherein the method comprises the steps of: There is provided a heat development method characterized by irradiating development light to a heat development recording material and performing development by photothermal conversion.

Preferably, the developing light does not include the photosensitive wavelength of the photosensitive heat-developable recording material.

The photothermal conversion is contained in at least one of an image forming layer, an upper layer of the image forming layer, and a lower layer of the image forming layer of the photosensitive heat-developable recording material.
It is preferable to use a material that absorbs the developing light.

Further, it is preferable that the developing light is far infrared rays or light emitted from a sodium lamp.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a heat developing method of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 shows an example of an image recording apparatus for performing the heat development method of the present invention. An image recording apparatus 10 (hereinafter, referred to as a recording apparatus 10) shown in FIG. 1 includes a photosensitive heat-developable recording material A (hereinafter, referred to as a photothermographic recording material A) having a photosensitive heat-developable image forming layer formed on a support such as a PET film. , Recording material A)
After imagewise exposing the recording material A to record a latent image, the exposed recording material A is heated and developed to develop a color, and is output as a hard copy on which an image is formed.

As the recording material A used in the heat development method of the present invention, various heat development (thermochromic) type recording materials capable of recording an image by exposure can be used.
Examples of suitable recording materials include the following.
First, on one surface of a support, a recording material (hereinafter referred to as a recording material) having an image forming layer in which 50% or more of a binder is composed of latex and contains an organic silver salt and a reducing agent for an organic silver salt.
As the first recording material). In the first recording material, a photocatalyst such as photosensitive silver halide forms a latent image nucleus when exposed to light, and is heated.
The silver of the organic silver salt, which has been ionized by the action of the reducing agent, moves and combines with the photosensitive silver halide to form crystalline silver and develop color to form an image.

The organic silver salt contained in the image forming layer of the first recording material is relatively stable to light, but is exposed to an exposed photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent. A silver salt that forms a silver image when heated to 80 ° C. or higher in the presence of, and may be desalted as necessary. Such organic silver salts include a silver salt of an organic acid, preferably a silver salt of a long-chain fatty carboxylic acid having 10 to 30 carbon atoms, and a complex stability constant having a ligand of 4.0 to 10.0. Complexes of organic or inorganic silver salts having, for example, silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, maleate Silver acid, silver fumarate, silver tartrate, silver linoleate, silver butyrate, silver camphorate and the like are exemplified.

Further, as the organic silver salt, a silver salt of a compound containing a mercapto group or a thione group and derivatives thereof can be preferably used. Specifically, 3-mercapto-4-phenyl-1,2,3 Silver salt of 4,4-triazole, 2
Silver salts of thioglycolic acid such as silver salts of mercaptobenzimidazole, silver salts of 2-mercapto-5-aminothiadiazole, silver salts of S-alkylthioglycolic acid,
Silver salt of dithiocarboxylic acid such as silver salt of dithioacetic acid, silver salt of thioamide, silver salt of 5-carboxyl-1-methyl-2-phenyl-4-thiopyridine, silver salt of mercaptotriazine, and silver salt of 2-mercaptobenzoxazole Silver salts and the like are exemplified.

The shape of such an organic silver salt is preferably a needle-like crystal having a short axis and a long axis. Specifically, the short axis is 0.01 μm to 0.20 μm, and the long axis is 0.10 μm to 5.0 μm.
0 μm is more preferred. Further, the organic silver salt is preferably monodispersed. Specifically, the standard deviation of the length of each of the short axis and the long axis is divided by the short axis and the long axis to be 100.
Preferably, the fraction is 100% or less.

Such an organic silver salt is used to obtain polyacrylic acid,
It is preferable to use a known dispersant such as polyvinyl alcohol and polyvinylpyrrolidone to obtain a solid fine particle dispersion. The dispersion of the organic silver salt into solid fine particles may be performed by a known mechanical fine particle dispersion method using a ball mill, a vibration ball mill, or the like in the presence of a dispersant. In addition to the mechanical dispersion method, the pH may be controlled so that the particles are roughly dispersed in the solvent, and then the pH is changed in the presence of a dispersing agent to form fine particles.

The amount of the organic silver salt is 0.1 to 5 g in terms of silver.
/ L is preferable, and more preferably 1 to 3 g / l.

The reducing agent for reducing such an organic silver salt is as follows:
Any substance that reduces silver ions to metallic silver can be used, and is preferably an organic substance, and is disclosed in Japanese Patent Application No. 57-82829.
Nos., JP-A-6-3793, etc., U.S. Pat.
Various known reducing agents used in photosensitive and heat-sensitive recording materials using organic silver salts, which are disclosed in JP-A-464738 and the like, can be used. Specifically, amide oximes such as phenylamide oxime; 4-hydroxy-3,5-
Azines such as dimethoxybenzaldehyde azine; Hydroxamic acids such as phenylhydroxamic acid; α such as ethyl-α-cyano-2-methylphenylacetate
-Cyanophenylacetic acid derivatives; bis-β-naphthol such as 2,2′-dihydroxy-1,1′-binaphthyl; 5-pyrazolone such as 3-methyl-1-phenyl-5-pyrazolone; dimethylaminohexose reductone Reductones such as 2,6-dichloro-4-benzenesulfonamidophenol and the like; sulfonamide phenol reducing agents such as 2,6-dimethyl-7-t-butyl-6-hydroxychroman; chromans such as 2,6-
1,4-dihydropyridines such as dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine; bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, 2,2-bis (4- (Hydroxy-3-methylphenyl) propane, 4,4-ethylidene-bis (2
-T-butyl-6-methylphenol), 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,
5,5-trimethylhexane, 2,2-bis (3,5-
Bisphenols such as dimethyl-4-hydroxyphenyl) propane; ascorbic acid derivatives such as 1-ascorbyl palmitate; chromanol such as tocopherol; and bisphenol and chromanol are particularly preferably used. In addition, known photographic developers such as phenidone, hydroquinone, and catechol are also preferably used, and a hindered phenol reducing agent is particularly preferable.

The reducing agent may be added by a method such as a solution, a powder, and a dispersion of solid fine particles. The dispersion of the solid fine particles is carried out by a known finer means (ball mill, vibrating ball mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used. The amount of the reducing agent is determined by the amount of silver 1 on the surface having the image forming layer.
It is preferably about 5 to 50 mol% based on mol. The reducing agent is
Basically, it is added to the image forming layer, but may be another layer on the side having the image forming layer. In this case, it is preferable to use a relatively large amount of 10 to 50 mol% with respect to 1 mol of silver.
Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

The image forming layer of the first recording material contains a substance which becomes a photocatalyst upon exposure, for example, photosensitive silver halide (hereinafter, referred to as silver halide). The halogen composition of the silver halide is not limited, and may be any of silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, and silver iodide. And silver iodobromide are preferably used. The grain size of the silver halide is preferably 0.20 μm or less to suppress white turbidity after image formation, and particularly preferred are cubic grains and tabular grains.

The silver halide grains include rhodium, rhenium, ruthenium, osmium, iridium, cobalt,
It is preferable that at least one complex of a metal selected from mercury or iron is contained in an amount of about 1 nmol to 10 mmol per 1 mol of silver. These metal complexes are disclosed in
It is described in detail in, for example, Japanese Patent No. 22549. The phase containing the metal complex in the silver halide may be uniform or may be contained at a high concentration in the core or the shell, and there is no particular limitation.

The silver halide grains are preferably chemically sensitized. The method of chemical sensitization is not particularly limited, and examples thereof include a sulfur sensitization method, a selenium sensitization method, a tellurium sensitization method using diacyl tellurides and bis (oxycarbonyl) tellurides, a chloroauric acid and potassium Noble metal sensitization using chloroaurate or the like, reduction sensitization using ascorbic acid, thiourea dioxide, or the like, sulfur sensitization, selenium sensitization, tellurium sensitization, and the like are exemplified. Further, a method of ripening the emulsion while keeping the pH of the emulsion at 7 or more or a pAg of 8.3 or less, and a method of introducing a single addition portion of silver ion during grain formation can also be used.

The amount of the silver halide used is preferably 0.01 mol to 0.5 mol per 1 mol of the organic silver salt. When the silver halide and the organic silver salt were separately prepared, the mixing method and the mixing conditions of the both were determined by using a high-speed stirrer, a ball mill, a sand mill, a colloid mill, a vibration mill, and the like. And a method of mixing with a homogenizer or the like, or a method of preparing an organic silver salt by mixing silver halide prepared at any timing during the preparation of the organic silver salt. Further, as a method for adjusting silver halide and mixing it with an organic silver salt, a so-called halation method in which a part of silver of the organic silver salt is halogenated with an organic or inorganic halide is preferably used. Examples of the organic halide used herein include N-halogenoimides such as N-bromosuccinimide, and quaternary nitrogen compounds such as tetrabutylammonium bromide. Examples of the inorganic halogen compounds include lithium bromide and potassium iodide. Alkali metal halides, ammonium halides such as ammonium bromide, alkaline earth metal halides such as calcium bromide, and halogen molecules such as bromine and iodine. The amount of halide to be added at the time of the validation is 1 mm as a halogen atom per 1 mol of the organic silver salt.
ol to 500 mmol are preferred.

In the first recording material, the image-forming layer having such a composition is prepared by dispersing a latex obtained by dispersing a water-insoluble hydrophobic polymer as fine particles in a water-soluble dispersion medium in an amount of 50 wt. % Or more. Alternatively, if necessary, other layers may have the same configuration. As the dispersion state of the latex, the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or partially hydrophilic in the polymer molecule and the molecular chain itself is a molecule. Any of those dispersed in a state may be used. Further, the latex may be a so-called core / shell type latex other than the latex having a normal uniform structure. For such latex, see "Synthetic Resin Emulsion (edited by Tadashi Okuda and Hiroshi Inagaki, published by Polymer Publishing Association (1978))", "Application of Synthetic Latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Keiji Kasahara, edited by Keiji Kasahara, Polymer) Publishing Association (1993)), and "Synthesis of Synthetic Latex (Souichi Muroi, Published by the Society of Polymer Publishing (1970))" and the like.

Examples of such latex polymers include acrylic resins, vinyl acetate resins, polyester resins, polyurethane resins, rubber resins, vinyl chloride resins,
Examples include vinylidene chloride resin and polyolefin resin. The polymer may be a linear polymer or a branched polymer, and may be crosslinked. Further, the polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized. In the case of a copolymer, it may be a random copolymer or a block copolymer. The molecular weight of the polymer is 5000 to 1,000,000 in number average molecular weight, preferably 10,000 to 10
About 0000 is preferable. If the molecular weight is too small, the mechanical strength of the photosensitive layer is insufficient, and if it is too large, the film-forming properties are poor, which is not preferable.

Specific examples of such a polymer include methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer,
Styrene / butadiene / acrylic acid copolymer, styrene / butadiene / divinylbenzene / methacrylic acid copolymer, methyl methacrylate / vinyl chloride / acrylic acid copolymer, vinylidene chloride / ethyl acrylate /
Acrylonitrile / methacrylic acid copolymer and the like are exemplified. Various commercial products can also be used as the polymer. For example, as the acrylic resin, Sebian A-4635 manufactured by Daicel Chemical Industries, Ltd., and as the polyester resin, FINETEX ES650 manufactured by Dainippon Ink and Chemicals, Inc.
HYDRAN AP10 manufactured by Dainippon Ink and Chemicals as polyurethane resin, LACSTAR 7310K manufactured by Dainippon Ink and Chemicals as rubber-based resin, G351 manufactured by Zeon Japan of vinyl chloride resin, and the like, Examples of the vinylidene chloride resin include L502 manufactured by Asahi Kasei Kogyo Co., Ltd., and examples of the polyolefin resin include Chemipearl S124 manufactured by Mitsui Petrochemical Co., Ltd. These polymers may be used alone or as a blend of two or more as necessary.

The average particle size of the dispersed particles in the latex is from 1 to
The range is preferably 50,000 nm, more preferably about 5 to 1,000 nm. There is no particular limitation on the particle size distribution of the dispersed particles, and a material having a wide particle size distribution or a material having a monodispersed particle size distribution may be used. Minimum film formation temperature of latex (MF
T) is −30 ° C. to 90 ° C., more preferably 0 ° C. to 70 ° C.
Is preferred.

As described above, in the image forming layer of the first recording material, it is preferable that 50% by weight or more of the total binder is latex, and that 70% by weight or more is latex. If necessary, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, or hydroxypropylmethylcellulose may be added to the image forming layer in a range of 50% by weight or less of the total binder. good. The amount of these hydrophilic polymers to be added is preferably 30% by weight or less of the total binder in the photosensitive layer. Further, it is preferable that the latex dispersed particles (polymer) have an equilibrium water content at 25 ° C. and 60% RH of 2% by weight or less, more preferably 1% by weight or less.

The image forming layer of the first recording material or another layer on the same surface as the image forming layer may contain an additive known as a toning agent, preferably silver 1 for the purpose of improving the optical density.
About 0.1 mol% to 50 mol% may be contained per mol.
The toning agent may be a precursor that is derivatized so as to have a function effectively only during development. As the color tone agent, various types of known color tone heat-sensitive recording materials can be used. Specifically, phthalimide compounds such as phthalimide; cyclic imides such as succinimide;
Naphthalimides such as hydroxy-1,8-naphthalimide; cobalt complexes such as cobalt hexamine trifluoroacetate; mercaptans such as 3-mercapto-1,2,4-triazole; phthalazinone derivatives such as 4- (1-naphthyl) phthalazinone And metal salts thereof, and the like, and are added to the coating solution as a solution, powder, or solid fine particle dispersion.

In the first recording material having such an image forming layer, if necessary, a sensitizing dye may be added to the image recording layer and / or another layer, preferably a silver halide of the image forming layer. It may contain about 10 ^-6 mol to 1 mol per 1 mol. As the sensitizing dye, any one can be used as long as it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains, such as a cyanine dye, a merocyanine dye, a complex cyanine dye, Complex merocyanine dyes, holo-holer cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes and the like can be used, and a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the recording light L may be selected. . To add sensitizing dyes to a silver halide emulsion, they may be dispersed directly in the emulsion, or may be dispersed in water, methanol, ethanol,
It may be dissolved in a single or mixed solvent such as N, N-dimethylformamide and added to the emulsion.

The image recording layer and / or other layers of the first recording material may contain an antifoggant, a stabilizer and a stabilizer precursor for the purpose of preventing additional fog and a decrease in sensitivity during storage. May be contained. Antifoggants, stabilizers and stabilizer precursors include US Pat. No. 2,131,038.
Thiazonium salts described in US Pat.
Azaindene described in 86,437, etc., mercury salts described in U.S. Pat. No. 2,728,663, and urazole described in U.S. Pat. No. 3,287,135. Further, as an antifoggant, JP-A-50-1
Organic halides disclosed in JP-A Nos. 19624 and 8-15809 are also preferably used. The antifoggant and the like may be added to the coating solution as a solution, a powder, a solid fine particle dispersion or the like.

The image recording layer and / or other layers of the first recording material may contain benzoic acids for the purpose of increasing sensitivity and preventing fog. As the benzoic acids, various benzoic acid derivatives can be used.
U.S. Pat. No. 4,787,939, Japanese Patent Application No. 8-15124
Compounds described in the specifications of No. 2 are added to the coating liquid as a powder, a solution, or a fine particle dispersion. Any amount of benzoic acid may be added,
It is preferably about 1 μmol to 2 mol per l.

The image recording layer and / or other layers of the first recording material may contain a mercapto compound, a cis sulfide or the like for the purpose of suppressing or accelerating the development, improving the spectral sensitization efficiency, and improving the storage stability before and after the development. Compounds and thione compounds may be contained. When a mercapto compound is used, any structure may be used, but Ar-SM, Ar-SS
-Ar is preferable, wherein M is a hydrogen atom or an alkali metal atom, and Ar is nitrogen, sulfur,
An aromatic ring or a condensed aromatic ring having at least one oxygen, selenium, or tellurium). Specifically, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2
-Mercaptobenzothiazole, 4,5-diphenyl-
Examples thereof include 2-imidazole thiol and 2-mercaptoimidazole. The addition amount of the mercapto compound is 1
It is preferably about 0.001 to 1.0 mol per mol.

The image recording layer and / or other layers of the first recording material may contain various dyes and pigments for the purpose of improving color tone and preventing irradiation. The dyes and pigments may be of any kind, and include, for example, pigments and dyes described in the Color Index.Specifically, pyrazoloazole dyes, anthraquinone dyes, azo dyes, azomethine dyes, oxonol dyes, carbocyanine dyes, styryl dyes, trityl dyes Phenylmethane dyes, indoaniline dyes, indophenol dyes, organic pigments such as phthalocyanine, inorganic pigments and the like, solutions, emulsions,
It is added to the coating liquid as a solid fine particle dispersion or mordant with a polymer mordant. The amount of these compounds to be used is determined depending on the target absorption, but is generally about 1 μg to 1 g per liter.

Further, in addition to these components, a plasticizer and a lubricant (for example, described in US Pat. No. 2,960,404) may be used in the image recording layer and / or other layers of the first recording material. Glycerin and diols), ultra-high contrast agents (for example, hydrazine derivatives described in Japanese Patent Application No. 8-148116), and high-contrast accelerators (for example, onium described in Japanese Patent Application No. 8-132636). Salts), hardeners (for example, polyisocyanates described in JP-A-6-208193) and the like.

The first recording material may have various layers in addition to the image forming layer. For example, a protective layer can be provided for the purpose of protecting the image forming layer and preventing adhesion. The protective layer is formed from an anti-adhesion material, and for example, wax, silica particles, styrene-containing elastomeric block copolymer (such as styrene-butadiene-styrene), cellulose acetate, cellulose acetate butyrate, and cellulose propionate are used. .

Further, an antihalation layer may be provided. The antihalation layer preferably has a maximum absorption in the desired wavelength range of 0.3 to 2 and an absorption in the visible region after treatment of 0.001 to 0.5. When an antihalation dye is used, the dye may be any compound as long as it has the desired absorption in the wavelength range, has a sufficiently low absorption in the visible region after the treatment and has the desired absorbance spectrum of the antihalation layer. For example,
The following are disclosed, but the present invention is not limited thereto. A single dye is disclosed in
Examples thereof include compounds disclosed in JP-A-11432 and JP-A-7-13295, and dyes which can be decolorized by the treatment are disclosed in JP-A-52-139136 and JP-A-7-199409. Compounds and the like are exemplified.

The first recording material preferably has an image forming layer on one side of the support and a back (coat) layer on the other side. A matting agent may be added to the back layer for improving transportability. The matting agent is generally fine particles of an organic or inorganic compound insoluble in water. Preferred examples of the organic compound include water-dispersible vinyl polymers such as polymethyl acrylate, methyl cellulose, carboxy starch, and carboxynitrophenyl starch.Examples of the inorganic compound include silicon dioxide, titanium dioxide, and the like.
Preferred examples include magnesium dioxide, aluminum oxide, and barium sulfate. The size and shape of the matting agent are not particularly limited, but those having a particle size of 0.1 μm to 30 μm are preferably used. Also. As a matte degree of the back layer, a Beck smoothness of 250 seconds to 10 seconds is preferable.

As the binder for forming the back layer,
Preferably, various colorless, transparent or translucent resins can be used, and examples thereof include gelatin, gum arabic, polyvinyl alcohol, hydroxyethyl cellulose, cellulose acetate, cellulose acetate butylate, casein, starch, and poly (meth) acryl. Examples thereof include acid, polymethyl methacrylic acid, and polyvinyl chloride. The back layer preferably has a maximum absorption of 0.3 to 2 in a desired wavelength range. If necessary, an antihalation dye used in the antihalation layer may be added.

Further, the surface on the back layer side is provided with a backside resistive heating layer (backside resistive heating layer) disclosed in each specification such as US Pat. Nos. 4,460,681 and 4,374,921.
may have an istive heating layer).

Further, in addition to these layers, the first recording material includes an antistatic or conductive layer using a soluble salt (for example, chloride, nitrate, etc.), a vapor-deposited metal layer, and US Pat.
It may have a layer containing an ionic polymer disclosed in US Pat. No. 861,056, a layer containing an insoluble inorganic salt disclosed in US Pat. No. 3,428,451, and the like.

Other examples of the preferable recording material A used in the present invention include the following.
This recording material (hereinafter, referred to as a second recording material) has an image forming layer in which the electron-donating colorless dye encapsulated in the thermoresponsive microcapsules and the thermoresponsive microcapsules have the same intramolecular structure. A recording material comprising a compound having an electron accepting portion and a polymerizable vinyl monomer portion, and a photopolymerization initiator.

Further, as another recording material (hereinafter, referred to as a third recording material), an image forming layer includes an electron-donating colorless dye encapsulated in a thermoresponsive microcapsule and a thermoresponsive microcapsule. In addition, a recording material containing an electron-accepting compound, a polymerizable vinyl monomer, and a photopolymerization initiator is also exemplified.

The second and third recording materials cure and fix the composition (hereinafter referred to as a photocurable composition) outside the thermoresponsive microcapsules by exposure, As a result, the compound having mobility (not immobilized) having the electron accepting portion and the polymerizable vinyl monomer portion or the electron accepting compound moves in the image forming layer, and the electron donating property in the microcapsule is changed. Is a recording material that forms an image by developing a colorless dye of the formula (1). Both recording materials are disclosed in Japanese Patent Application No. 8-3337 by the present applicant.
No. 24 is described in detail.

The compound having an electron-accepting portion and a polymerizable vinyl monomer portion in the same molecule, which is used in the photocurable composition of the second recording material, refers to an electron-accepting group and a vinyl group in one molecule. Is a compound containing Specifically, styrenesulfonylaminosalicylic acid, vinylbenzyloxyphthalic acid, zinc β- (meth) acryloxyethoxysalicylate, vinyloxyethyloxybenzoic acid, β- (meth) ataacryloxyethylorselinate, β- ( (Meth) acryloxyethoxyphenol, β- (meth) acryloxyethyl-β-resorcinate, hydroxystyrenesulfonic acid-N-ethylamide, β- (meth) acryloxypropyl-p-hydroxybenzoate,
(Meth) acryloxymethylphenol, (meth) acrylamidopropanesulfonic acid, β- (meth) acryloxyethoxy-dihydroxybenzene, γ-styrenesulfonyloxy-β- (meth) acryloxypropanecarboxylic acid, γ- (meth) Acryloxypropyl-α-hydroxyethyloxysalicylic acid, β-hydroxyethoxycarbonylphenol, 3,5-distyrenesulfonic amide phenol, (meth) acryloxyethoxyphthalic acid, (meth) acrylic acid, (meth) acryloxyethoxy Hydroxynaphthoic acid, β- (meth) acryloxyethyl-p-hydroxybenzoate, β ′-(meth) acryloxyethyl-β-resorcinate, β-
(Meth) acryloxyethyloxycarbonylhydroxybenzoic acid and the like, and metal salts thereof such as zinc salt can be preferably used.

The above compound can be suitably used also as a polymerizable vinyl monomer of the photocurable composition of the third recording material. In addition, as the polymerizable vinyl monomer used in the third recording material, various other monomers having at least one vinyl group in a molecule can be used. For example, (meth) acrylic acid and its monomer can be used. Salts, (meth) acrylic esters, (meth) acrylamides; maleic anhydride, maleic esters; itaconic acid, itaconic esters; styrenes; vinyl ethers and esters; N-vinyl heterocycles;
Allyl ethers and esters can be used. In particular, a monomer having a plurality of vinyl groups in the molecule is preferable. For example, (meth) acrylates of polyhydric alcohols, polyhydric phenols, (meth) acrylates of bisphenols, and (meth) acrylate-terminated epoxy There are resins and (meth) acrylate-terminated polyesters. Specifically, ethylene glycol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hydroxypentaacrylate, hexanediol-1,
5-dimethacrylate, diethylene glycol dimethacrylate and the like are exemplified. As these monomers, those having a molecular weight of about 100 to about 5000 are preferably used.

The photopolymerization initiator used for the second and third recording materials is a compound capable of initiating the photopolymerization of the vinyl monomer, and is preferably used in combination with a green, red to infrared absorbing dye. In addition, it has sensitivity in this wavelength region and is supposed to generate radicals upon irradiation with light (Japanese Patent Application Laid-Open No. Sho 62-62).
No. 143044) Organic borate salt compounds, more preferably organic borate salts of cationic dyes. The organic borate generates a radical in response to the irradiated laser beam, and the radical initiates the polymerization of the vinyl monomer portion.

As the organic borate, a compound represented by the following general formula (1) is used.

Embedded image

In the above general formula (1), M is
Li metal atom, quaternary ammonium, pyridinium, quino
Linium, diazonium, morpholinium, tetrazoli
, Acridinium, phosphonium, sulfonium,
Oxosulfonium, sulfur, oxygen, carbon, halogeniu
, Cu, Ag, Hg, Pd, Fe, Co, Sn, M
cation selected from o, Cr, Ni, As, Se
N is an integer of 1 to 6, R ¹, R^Two, R^ThreeAnd R^Four
Each represents a halogen atom, a substituted or unsubstituted alkyl
Group, substituted or unsubstituted alkenyl group, substituted or unsubstituted
Substituted alkynyl group, alicyclic group, substituted or unsubstituted ant
Alkenyl group, substituted or unsubstituted alkaryl group,
Is an unsubstituted aryloxyl group, a substituted or unsubstituted
Alkyl group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted
Represents a substituted silyl group. Where R¹, R^Two, R^ThreeAnd
And R^FourMay be the same or different from each other, and these
Of these, two or more groups may be bonded to form a cyclic structure.

In the above formula (1), examples of the borate anion include tetraethyl borate, triisobutyl methyl borate, di-n-butyl-di-t-butyl borate, tetraphenyl borate, tetra-p-chlorophenyl borate, and tri-borate. m-chlorophenyl-n-hexyl borate, triphenylethyl borate, trimethylbutyl borate, tolyl isopropyl borate,
Triphenylbenzyl borate, tetraphenyl borate, tetrabenzyl borate, triphenylphenethyl borate, triphenyl-p-chlorobenzyl borate, triphenylethenituburiborate, di (α-nephthyl) -dipropyl borate, triphenylsilyl triphenyl Examples thereof include borate, tritolylsilylphenyl borate, and tri-n-butyl (dimethylphenylsilyl) borate.

The following is an example of the organic borate salt represented by the general formula (1).

Embedded image

In order to increase the light absorption efficiency of the recording light L or the like,
The organic borate salt represented by the general formula (1) is preferably used as a spectral sensitizing dye in combination with green to red and infrared absorbing dyes. Particularly, the maximum absorption wavelength is 500 to 1
Organic cationic dyes having a wavelength range of 100 nm are preferably used, and specifically, cationic methine dyes,
Examples include a cationic carbonium dye, a cationic quinone imine dye, a cationic indoline dye, and a cationic styryl dye. More specifically, as the cationic methine dye, polymethine dye, cyanine dye, azomethine dye, more preferably cyanine, carbocyanine, dicarbocyanine, tricarbocyanine, hemicyanine, etc., as a cationic carbonium dye , A triarylmethane dye, a xanthene dye, an aridudine dye, more preferably rhodamine, etc., and as the cationic quinone imine dye, a dye selected from azine dyes, oxazine dyes, thiazine dyes, quinoline dyes, thiazole dyes, These can be used alone or in combination of two or more.

The photopolymerization initiator is more preferably
An organic borate salt of a cationic dye represented by the following general formula (2) is used.

[0057]

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In the above formula (2), D ⁺ represents a cationic dye, and R ¹ , R ² , R ³ and R ⁴ are a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl. Group, substituted or unsubstituted aralkyl group, substituted or unsubstituted alkaryl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted alkynyl group, substituted or unsubstituted aryloxyl group, substituted or unsubstituted allylic group It is a group selected from a click group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted allyl group, a substituted or unsubstituted silyl group, and an alicyclic group. Also,
R ¹ , R ² , R ³ and R ⁴ may be the same or different from each other, and two or more of these groups may be bonded to form a cyclic structure.

In the above general formula (2), the cationic dye represented by D ⁺ acts as a spectral sensitizing dye, and has a wavelength region of 500 nm or more, particularly 550 nm to 550 nm.
An organic cationic dye having an absorption peak in a wavelength region of 1100 nm is preferably exemplified. Specific examples include a cationic methine dye, a cationic carbonium dye, a cationic quinone imine dye, a cationic indoline dye, and a cationic styryl dye.More specifically, the cationic methine dye is preferably polymethine. Dyes, cyanine dyes, azomethine dyes, more preferably cyanine, carbocyanine, dicarbocyanine, tricarbocyanine, hemicyanine, etc., as cationic carbonium dyes, preferably triarylmethane dyes, xanthene dyes, alicudin dyes, Preferably, rhodamine or the like is used, and as the cationic quinone imine dye, preferably, a dye selected from an azine dye, an oxazine dye, a thiazine dye, a quinoline dye, and a thiazole dye is used. Further, as the borate anion, the same ones as in the general formula (1) are preferably exemplified.

The following is an example of the organic borate salt of the cationic dye represented by the general formula (2).

Embedded image

[0061]

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The content of these photopolymerization initiators is preferably 0.01% by weight to 20% by weight based on the total weight of the photocurable composition (outside of the thermoresponsive microcapsules).

In this thermochromic recording material, together with the photopolymerization initiator and the spectral sensitizing dye, the following general formula (3):
A compound represented by the general formula (4) and having an active halogen group in the molecule can be used as an auxiliary.

[0064]

Embedded image In the general formula (3), X represents a halogen atom, and Y ¹ represents-
_{CX 3, -NH 2, -NHR,} -NR 2, represents an -OR. Here, R represents an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. Y ² is -CX ₃ ,
Represents an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, or a substituted alkenyl group. The substituent may be the general formula (3) itself.

[0065]

Embedded image In the general formula (4), X represents a halogen atom.
Y ³ and Y ⁴ may be the same or different and represent a hydrogen atom or a halogen atom. Z represents a group represented by the following formula.

Embedded image Here, R ¹ is a hydrogen atom, a halogen atom, an alkyl group,
Represents a substituted alkyl group, an aryl group, a substituted aryl group, a substituted alkenyl group, a heterocyclic group, or a substituted heterocyclic group.

As the compound represented by the general formula (3), a compound in which Y ¹ is CX ₃ is preferably used. Specifically, as the compound represented by the general formula (3), 2-phenyl-4,6-bis (trichloromethyl) -S-triazine, 2- (p-chlorophenyl)-
4,6-bis (trichloromethyl) -S-triazine,
2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -S-triazine, 2,4,6-tris (trichloromethyl) -S-triazine, 2- (p-cyanophenyl) -4, 6-bis (trichloromethyl)-
S-triazine, 2- (p-acetylphenyl) -4,
6-bis (trichloromethyl) -S-triazine and the like are preferably excited.

On the other hand, the compounds represented by the general formula (4) include carbon tetrachloride, carbon tetrabromide, iodoform,
-Nitro-α, α, α-tribromoacetophenone,
ω, ω, ω-Tribromoquinaldine, tribromomethylphenylsulfone, trichloromethylphenylsulfone and the like.

The compound represented by the general formula (3) or (4) is a compound having a spectral sensitizing dye (cationic dye) of 1 mole.
It is preferable to add 0.01 to 20 mol of the compound represented by the general formula (3) or (4) to l.

The second and third recording materials have high sensitivity and are sensitive to infrared light. However, as an auxiliary for promoting the formation of a latent image, a reducing agent such as an oxygen scavenger (oxygen sca) is used.
venger) and a chain transfer agent of an active hydrogen donor, and other compounds may be used in combination. Oxygen scavengers that have been found to be useful as auxiliaries to promote latent image formation are phosphines, phosphonates, phosphites, stannous salts, and other compounds that are easily oxidized by oxygen, For example, N-phenylglucin, trimethylbarbituric acid, N, N-dimethyl-2,6-diisopropylaniline and the like are exemplified.

An electron-accepting compound is added to the photocurable composition of the third recording material. Further, an electron-accepting compound may be added to the photocurable composition of the second recording material, if necessary, so that the coloring density can be improved.
Examples of the electron-accepting compound include phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids, acid clay,
Bentonite, novolak resin, metal-treated novolak resin, metal complex, and the like. In addition, as a phenol derivative, 2,2'-bis (4-hydroxyphenyl) propane, 4-t-butylphenol, 4-phenylphenol, 4-hydroxydipheninoxide, 1,1,
Examples thereof include 1'-bis (3-chloro-4-hydroxyphenyl) cyclohexane and 1,1'-bis (3-chloro-4-hydroxyphenyl) -2-ethylbutane.
Examples of salicylic acid derivatives include 4-pentadecylsalicylic acid, 3,5-di (α-methylbenzyl) salicylic acid, 3,5-di (tert-octyl) salicylic acid,
-Octadecylsalicylic acid, 5-α- (p-α-methylbenzylphenyl) ethylsalicylic acid, 3-α-methylbenzyl-5-tert-octylsalicylic acid, 5-tetradecylsalicylic acid, and the like. These electron accepting compounds are used in an amount of from 5% by weight to 100% by weight of the electron donating colorless dye.
It is preferable to use about 0% by weight.

The photocurable compositions of the second and third recording materials include, in addition to these compounds, a photocrosslinkable composition such as polyvinyl cinnamate, polycinnamylidene vinyl acetate, α -A photocurable composition having a phenylmaleimide group may be added. Further, these photocrosslinkable compositions may be used as photocurable components.

Further, in the photocurable composition, in addition to these compounds, if necessary, thermal and temporal polymerization of the photocurable composition can be prevented to enhance the stability. For the purpose, a thermal polymerization inhibitor may be added. Examples of the thermal polymerization inhibitor include p-methoxyphenol, hydroquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine, chloranil, naphthylamine, β-naphthol, 2,6-di-t
-Butyl-p-cresol, nitrobenzene, dinitrobenzene, picric acid, p-toluidine and the like are preferably exemplified, and 0.001% by weight based on the total weight of the photocurable composition.
It is preferable to add about 5% by weight.

The photocurable composition is emulsified and dispersed and contained in the image forming layer. Examples of the solvent used for emulsifying and dispersing the photocurable composition include cottonseed oil, kerosene, aliphatic ketone, aliphatic ester, paraffin, naphthenic oil, alkylated biphenyl, chlorinated paraffin, 1,1′-ditolylethane, and the like. Diaryl ethane, alkyl phthalates such as dibutyl phthalate, phosphates such as diphenyl phosphate, citrates such as tributyl acetyl citrate, benzoates such as octyl benzoate, alkyl amides such as diethyl lauramide, ethyl acetate and the like Examples include acetate esters, (meth) acrylate esters such as methyl (meth) acrylate, alkyl halides such as methylene chloride and carbon tetrachloride, methyl isobutyl ketone, β-ethoxyethyl acetate, methyl cellosolve acetate, and the like. Particularly, aliphatic esters and alkyl halides are preferable, and those having a solubility in water of 10% by volume or less are more preferable. These solvents are preferably used in a proportion of 1 part by weight to 500 parts by weight based on the photopolymerizable compound.

As the water-soluble polymer that can be used for emulsifying and dispersing the photocurable composition, a compound that is soluble in water at 25 ° C. in an amount of 5% by weight or more is preferable. Derivatives, proteins such as albumin, cellulose derivatives such as methylcellulose, sugar derivatives such as starches (including modified starch), polyvinyl alcohol, styrene-maleic anhydride co-weight hydrolyzate, carboxy-modified polyvinyl alcohol, polyacrylamide, acetic acid Saponified vinyl-polyacrylic acid copolymers and synthetic polymers of polystyrene sulfonate sugars are exemplified, and gelatin and polyvinyl alcohol are particularly preferred.

On the other hand, the electron-donating colorless dye encapsulated in the microcapsules of the image forming layers of the second and third recording materials are conventionally known triphenylmethanephthalide compounds, fluoran compounds and phenothiazines. Various compounds such as a compound based on an indolyl phthalide, a compound leuco auramine, a compound based on a rhodamine lactam, a compound based on a totaphenylmethane, a compound based on a triazene, a compound based on a spiropyran and a compound based on a fluorene can be used. Specifically, triphenylmethanephthalide-based compounds include 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide and 3- (p-dimethylaminophenyl) -3- (2-methyl Indole-3
-Yl) phthalide and the like; leuco auramine compounds such as N-halophenyl-leuco auramine and N-2,
4,5-trichlorophenylleuco auramine and the like;
Rhodamine lactam compounds include rhodamine-B-
Anilinolactam and rhodamine- (p-nitrino) lactam, etc .: Examples of fluoran compounds include 2- (dibenzylamino) fluoran and 2-anilino-3-methyl-
6-diethylaminofluoran, 2-anilino-3-methyl-6-N-methyl-N-cyclohexylaminofluoran and the like; phenothiazine compounds such as benzoylleuconmethylene blue and p-nitrobenzylleucomethylene blue; spiropyran compounds Examples of the compound include 3-methyl-spiro-dinaphthopyran and 3,3'-dichloro-spiro-dinaphthopyran;

Microcapsules containing such an electron-donating colorless dye can be obtained by a method known in the art. For example, US Pat. No. 2,800,457
U.S. Pat. No. 3,660,304, which discloses a method utilizing coacervation of a hydrophilic wall-forming material disclosed in Japanese Patent Application Publication No. 42-771 and an interfacial polymerization method disclosed in Japanese Patent Publication No. 42-771. By using the isocyanate polyol wall material disclosed in U.S. Pat. No. 3,796,669, U.S. Pat.
A method using an isocyanate wall material disclosed in 914,511, a method using a urea formaldehyde-resorcinol-based wall forming material disclosed in U.S. Pat. No. 4,089,802, and the like are disclosed. Especially,
It is preferable to form a polymer film as a microcapsule wall after emulsifying the core substance.

Among them, a microencapsulation method by polymerization of a reactant from the inside of an oil droplet is particularly preferable because a recording material having a capsule having a uniform particle size and excellent storage properties can be obtained within a short time. For example, when polyurethane is used as a capsule wall material, a polyvalent isocyanate and a second substance (eg, polyol, polyamine) which reacts with the polyisocyanate to form a capsule wall are mixed in an oily liquid to be encapsulated and emulsified in water. By dispersing and then raising the temperature, a polymer forming reaction occurs at the oil droplet interface to form microcapsule walls. At this time, an auxiliary solvent having a low boiling point and strong dissolving power can be used in the oily liquid.

The polyvalent isocyanate used in this case includes m-phenylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, diphenylmethane-4,4-diisocyanate,
Various polyvalent isocyanates for producing known urethane resins, such as xylylene-1,4-diisocyanate, 4,4'-diphenylpropane diisocyanate, trimethylene diisocyanate, and hexamethylene diisocyanate, can be used. The polyvalent isocyanate can also react with water to form a polymer. Further, as the polyol, aliphatic, aromatic polyhydric alcohol,
Hydroxypolyester, hydroxypolyalkylene ether, etc., specifically, ethylene glycol, 1,3
-Propanediol, 1,4-butanediol, 1,5
-Pentanediol, 1,6-hexanediol, propylene glycol, 2,3-dihydroxybutane, 1,
2-dihydroxybutane, 2,5-hexanediol,
Various polyols, such as 3-methyl-1,5-pentanediol and dihydroxycyclohexane, for producing known urethane resins can be used. The polyol has a hydroxyl group ratio of 0.1 mol per 1 isocyanate group.
It is preferable to use about 02 mol to 2 mol. further,
Examples of the polyamine include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenedimian, p- (m-) phenylenediamine, piperazine and derivatives thereof, 2-hydroxytrimethylenediamine, diethylenetriamine, triethylenetriamine, triethylenetriamine, and triethylenetriamine. Examples include ethylene tetramine, tetraethylene pentamine, and amine adducts of epoxy compounds.

Microcapsules can also be prepared using a water-soluble polymer. The water-soluble polymer at this time may be any of a water-soluble anionic polymer, a nonionic polymer, and an amphoteric polymer. As the anionic polymer, -CO
Examples thereof include those having an O-, -SO ₂ -group or the like, and specifically, gelatin derivatives such as arabic gum, alginic acid, sulfated starch, sulfated cellulose, phthalated gelatin, and (meth) acrylic acid (co) Polymers, vinylbenzenesulfonic acid (co) polymers, carboxy-modified polyvinyl alcohols, etc .; nonionic polymers such as polyvinyl alcohol and hydroxyethyl cellulose; and amphoteric compounds such as gelatin. , Gelatin derivatives and polyvinyl alcohol are preferred. The water-soluble polymer is used as an aqueous solution of 0.01% by weight to 10% by weight.

In such second and third recording materials, the average particle diameter of the capsule is preferably 20 μm or less, particularly preferably 5 μm or less from the viewpoint of resolution. On the other hand, if the capsule is too small, the surface area for a certain solid content becomes large, and a large amount of a wall material is required. Therefore, the thickness is preferably 0.1 μm or more.

The electron-donating colorless dye may be present in the microcapsules in a solution state or in a solid state. When an electron-donating colorless dye is present in a solution state, the dye may be encapsulated in a state of being dissolved in a solvent. At this time, the amount of the solvent is preferably 1 to 500 parts by weight based on 100 parts by weight of the electron-donating colorless dye. As a solvent used at the time of encapsulation,
The same solvent as that used for emulsifying the photocurable composition can be used. Also, at the time of microencapsulation,
As an auxiliary solvent for dissolving the electron-donating colorless dye,
A volatile solvent such as an acetate-based solvent may be used in combination with another solvent.

The second and third recording materials may have various layers such as a protective layer and an intermediate layer in addition to the image forming layer, and a matting agent may be added to the protective layer. Is preferred. Examples of the matting agent include inorganic particles such as silica and magnesium oxide, resin particles such as polymethyl methacrylate and polystyrene, and starch particles such as carboxy starch.Particularly, polymethyl methacrylate particles and silica particles are preferably used. . FUJI as silica particles
-Syloid AL series manufactured by DEVISON CHEMICAL LTD. Is available. The particle size of the matting agent is 1 μm to 20 μm
m is preferable, and the addition amount is 2 mg / m ^{2 to} 500
mg / m ² is preferred.

It is preferable to use a curing agent in each of the image forming layer, the intermediate layer and the protective layer of the recording material.
In particular, it is preferable to use a curing agent in the protective layer to reduce the tackiness of the protective layer. As the curing agent, a "gelatin curing agent" used in the production of a photographic recording material is useful, and specifically, chrom alum, zirconium sulfate, boric acid,
1,3,5-triacroyl-hexahydro-s-triazine, 1,2-bisvinylsulfonylmethane, 1,3
-Bis (vinylsulfonylmethyl) propanol-2,
Bis (α-vinylsulfonylacetamido) ethane,
2,4-dichloro-6-hydroxy-s-triazine.
Sodium salts, 2,4,6-triethylenino-s-triazine and the like are preferably exemplified. The amount of the curing agent added in each layer is 0.5% by weight to 5% by weight of the binder.
% By weight is preferred.

Further, colloidal silica may be added to the protective layer in order to reduce the adhesiveness. As the colloidal silica, for example, Nissan Chemical's Snowtex 20, Snowtex 30, Snowtex C, Snowtex O, Snowtex N, etc. can be used. % By weight is preferred. It is preferred to add. Further, a fluorescent whitening agent for increasing the whiteness of the recording material or a blue dye as a bluing agent may be added to the protective layer.

When the second and third recording materials are made into a multicolor recording material, for example, a microcapsule containing an electron-donating colorless dye which develops a different hue and a photo-curing photosensitive to light of a different wavelength are used. Alternatively, an intermediate layer containing a filter dye may be provided between the light-sensitive and heat-sensitive layers, using a multi-layered recording material having a photosensitive composition in each layer. The intermediate layer is mainly composed of a binder and a filter dye, and can contain additives such as a curing agent and a polymer latex, if necessary. The dye for the filter can be emulsified and dispersed by an oil-in-water dispersion method or a latex dispersion method and added to a desired layer, particularly an intermediate layer. In the oil-in-water dispersion method, the boiling point is, for example, 175.
Organic solvent having a high boiling point of 30 ° C. or more and, for example, a boiling point of 30 ° C. to 1 ° C.
After dissolving in either one of the so-called auxiliary solvents at 60 ° C. or a mixture thereof, it is finely dispersed in an aqueous medium such as water or an aqueous gelatin solution in the presence of a surfactant. Specific examples of the latex dispersion method and the latex for curing and impregnation are described in U.S. Pat. No. 4,199,383. Suitable latexes include, for example, (meth) acrylates such as ethyl acrylate. ) A copolymer latex of an acrylate and an acid monomer such as acrylic acid is preferred.

In the second and third recording materials,
As a binder for each layer such as a protective layer, an image forming layer, and an intermediate layer, emulsification and dispersion of a photocurable composition and, in addition to a water-soluble polymer used for encapsulation of an electron-donating colorless dye, polystyrene, polyvinyl formal, Acrylic resin such as polyvinyl butyral, polyvinyl alcohol and polymethyl acrylate, phenol resin, ethyl cellulose,
A solvent-soluble polymer such as an epoxy resin or a urethane resin, or a polymer latex thereof can also be used.
Among these, gelatin and polyvinyl alcohol are preferred.

Each layer of the second and third recording materials has a coating aid, an antistatic property, an improvement in slipperiness, an emulsification dispersion,
A surfactant may be used for the purpose of preventing adhesion or the like. Examples of the surfactant include nonionic surfactants such as saponin, polyethylene oxide and its derivatives, alkyl sulfonates, alkyl sulfates, and N-acyl-
N-alkyltaurines and the like can be used as needed. In addition to the additives described so far, if necessary, dyeing agents to prevent irradiation and halation,
An ultraviolet absorber, a plasticizer, a fluorescent brightener, a coating aid, a curing agent, an antistatic agent, a slipperiness improver, and the like may be added.

The heat development method of the present invention comprises a first recording material,
(Photosensitive thermal development) Recording material A such as a second recording material and a third recording material is thermally developed by photothermal conversion using developing light to obtain a hard copy on which an image is formed. .

As shown in FIG. 2, the recording material A is obtained by forming an image forming layer 94 on a support 92 or, if necessary, forming various layers such as a protective layer 96. As described above, in the recording material A of the illustrated example, in a preferred embodiment, the image forming layer 94 and the upper and lower layers of the image forming layer In the illustrated example, at least one of the protective layer 96 and the layer indicated by reference numeral 98 contains a substance that absorbs developing light, for example, a dye that absorbs developing light. With such a configuration, in the heat development using the developing light, the developing light can be suitably converted to heat, and the image forming layer 94 can be suitably heated without unnecessary heating of the support 92 and the like. And thermal development with good energy efficiency can be performed.

In the illustrated recording material A, the protective layer 9
6 is the upper layer of the image forming layer 94, but the recording material A used in the present invention is not particularly limited to this configuration, and another layer may be the upper layer of the image forming layer 94. .
Further, the layer indicated by reference numeral 98 may be a layer having some function, or may be a layer added only for the purpose of suitably performing heat development by photothermal conversion. Further, a layer for the purpose of only performing suitable thermal development is placed on the image forming layer 94 (that is, in the illustrated example, the protective layer 9).
6 position).

The substance that absorbs the developing light may be appropriately selected according to the developing light to be used. In addition, such a substance
Of the image forming layer 94 and its upper and lower layers, it may be contained in only one layer, may be formed in two layers, or may be contained in all three layers. Preferably, it is contained in the image forming layer 94.
Further, such a substance may be contained in a layer other than the above three layers or the support 92 as necessary.

The recording material A (first recording material,
The second recording material and the third recording material) are prepared by preparing a coating solution (emulsion) containing the components of each layer using a solvent, if necessary, coating by a known means, and drying. Can be made. As the solvent, various solvents used for producing the recording material can be used. Specifically, water, alcohols such as ethanol and isopropanol, halogen-based solvents such as ethylene chloride, ketones such as cyclohexanone and methyl ethyl ketone. , Esters such as methyl acetate cellosolve and ethyl acetate, toluene, xylene, etc. are exemplified.If necessary, a plurality of types may be used in combination. Various surfactants such as nonionic, anionic, cationic, and fluorine may be added. As a coating method, known methods such as a blade coater, a rod coater, a knife coater, a roll doctor coater, a reverse roll coater, a transfer roll coater, a gravure coater, a kiss roll coater, and a curtain coater can be used. In addition,
It is a matter of course that the application amount of each paint is adjusted so that the adhesion amount of each layer after drying becomes a predetermined amount.

The support 92 of the recording material A is not particularly limited, and various materials used for ordinary recording materials can be used. Specifically, polyester films, polyethylene terephthalate (PET) films ,
Examples thereof include resin films such as polyethylene naphthalate film, cellulose nitrate film, cellulose ester film, polyvinyl acetal film, and polycarbonate film, various metals such as aluminum, zinc, and copper, glass, and paper.

In order to properly irradiate the layer containing the substance that absorbs the developing light with the developing light and to suitably perform the thermal development by photothermal conversion, the layers formed on the recording material A and the support 92 are preferably used. It is preferable that at least the layer on the side where the developing light enters than the layer containing the substance that absorbs the developing light is light-transmissive before the development.

Recording apparatus 1 using such a recording material A
Reference numeral 0 basically includes a photosensitive material supply unit 12, a width adjustment unit 14, an image exposure unit 16, and a heat development unit 18 in the order of conveyance of the recording material A.

The recording material A is stored in a state of being stacked on a dedicated magazine 20 and supplied to the recording apparatus 10. A photosensitive material supply unit 12 (hereinafter, referred to as a supply unit 12) takes out one recording material A from the magazine 20 and places the recording material A at a downstream position (hereinafter, referred to as downstream) in the transport direction of the recording material A. 14 and the loading units 22 and 24
Sheet feeding means using suction cups 26 and 28 disposed in each loading section; supply roller pairs 30 and 32; transport roller pairs 34 and 36; and transport guides 38, 40 and 4
2 is provided.

The loading sections 22 and 24 are sections for loading the magazine 20 containing the recording material A at a predetermined position.
The illustrated recording apparatus 10 includes two loading units 22 and 24.
Usually, recording materials A having different sizes (for example, half-cut size for CT and MRI, B4 size for FCR (Fuji Computed Radiography), etc.) are stored in both loading sections. The magazine 20 is loaded.
The single-wafer means arranged in each loading section includes suckers 26 and 28
The recording material A is sucked and held, and the recording material A is conveyed by moving the suction cups 26 and 28 by a known moving means such as a link mechanism, and is supplied to the supply roller pairs 30 and 32 disposed in the respective loading sections. Supply. The recording material A supplied to the supply roller pair 30 is supplied to the conveyance guides 38 and 4.
The recording material A supplied to the supply roller pair 32 while being guided by the transport rollers 40 while the guide material 40 is guided by the transport guides 40 and 42. 14.

The width shifter 14 aligns the recording material A in a direction perpendicular to the conveyance direction (hereinafter, referred to as a width direction), and thereby the position of the recording material A in the main scanning direction in the downstream recording unit 16. At this time, the recording material A is conveyed to the downstream recording unit 16 by the conveying roller pair 44 after taking a so-called side resist. There is no particular limitation on the method of the side resist in the width shifter 14. For example, there is a resist plate for positioning by contacting one end surface in the width direction of the recording material A, and an end surface by pushing the recording material A in the width direction. Using a pressing means for bringing the recording material A into contact with the resist plate, and controlling the conveying direction of the resist material and the recording material A in the width direction and making the recording material A contact the resist plate in the same manner. Such as using a guide plate that can be moved according to
Various known methods are exemplified. Further, the side resist may be a center reference based on the center of the recording material A in the width direction or an end surface reference based on the end surface of the recording material A.

The image exposing section 16 (hereinafter, referred to as the exposing section 16) is a portion for imagewise exposing the recording material A by light beam scanning exposure to record a latent image. And is configured.

FIG. 3 shows a conceptual diagram of the exposure unit 16. The exposure unit 46 includes a light beam L modulated according to a recorded image.
Is a known light beam scanning device that deflects light in a main scanning direction (a direction perpendicular to the paper surface in FIGS. 1 and 3) and enters a predetermined recording position X. A control device 52 and a polygon mirror 54 as an optical deflector
, Fθ lens 56, and falling mirror 58. In addition, the exposure unit 46 includes a known light beam scanning device such as a collimator lens or a beam expander for shaping the light beam L emitted from the light source, a surface tilt correction optical system, an optical path deflection mirror, or the like. Various members to be arranged are arranged as needed.

The light source 50 is a light source that emits a light beam L in a narrow wavelength range according to the spectral sensitivity characteristics of the recording material A, and is driven by the exposure control device 52. In the recording apparatus 10 according to the present invention, the method of modulating the light beam L is not particularly limited, and may be pulse (width or number) modulation or intensity modulation. In the illustrated example, the light beam L is modulated in accordance with the recorded image by direct modulation, in which the exposure control device 52 controls the driving of the light source 50 to perform modulation. External modulation using a modulator such as an optical modulator or an EOM (electro-optic modulator) may be used.

The light beam L emitted from the light source 50 after being subjected to the pulse width modulation is deflected in the main scanning direction by the polygon mirror 54, and is modulated by the fθ lens 56 so as to form an image at the recording position X. Falling mirror 58
As a result, the optical path is changed, and the light enters the recording position X. The recording device 10 in the illustrated example is a device that performs monochrome image recording, and the exposure unit 46 has only one light source 50. However, when the present invention is used for recording a color image, for example, a color photosensitive material is used. R (red), G (green), and B
An exposure unit having three types of light sources that emit light beams having wavelengths corresponding to the spectral sensitivity characteristics of (blue) is used.

On the other hand, the sub-scanning conveyance means 48
A pair of transport rollers 60 arranged with the (scanning line) interposed therebetween
The recording material A is conveyed in the sub-scanning direction (the direction of arrow a in FIG. 3) orthogonal to the main scanning direction while holding the recording material A at the recording position X by the conveying roller pairs 60 and 62. Here, as described above, the light beam L pulse-modulated in accordance with the recorded image is deflected in the main scanning direction, so that the recording material A is two-dimensionally scanned and exposed by the light beam to form a latent image. Is recorded.

Although the recording apparatus 10 of the illustrated example forms a latent image by light beam scanning exposure, in the present invention,
In addition, LED (light emitting diode) array, LC
An exposure method using a light emitting element array such as a D (liquid crystal display) array, a liquid crystal shutter array, or a spatial modulation element array can also be used.

The recording material A on which the latent image has been recorded in the exposure section 16 is then transferred to the conveying roller pairs 64, 66 and 6
8, is conveyed by the conveying roller 70, the conveying guide 72, and the like, and is conveyed to the thermal developing unit 18. The heat developing section 18 is a portion where the recording material A is heated to perform heat development to make a latent image a visible image. In the recording apparatus 10 using the heat developing method of the present invention, a developing light is used. The image forming layer 94 of the recording material A is heated by light-to-heat conversion to develop a color in accordance with the latent image formed by exposure, thereby obtaining a hard copy on which an image is formed. Such a heat development unit 18 includes a heat development light source 74, a reflector 76, a filter 78, and a reflection plate 8
0, conveying roller pairs 82 and 8 for conveying the photosensitive material A
4.

The heat development light source 74 is a light source for developing light, and appropriately selects a light source having a sufficient light amount for heat development by photothermal conversion according to the spectral sensitivity characteristics of the recording material A to be used and the amount of heat required for heat development. do it. Specifically, a far-infrared light source, a low-pressure sodium lamp, and the like are preferably exemplified in terms of light quantity, wavelength characteristics, and the like. Further, the reflector 76 and the reflection plate 80 reflect the developing light emitted from the heat developing light source 74 so that the developing light is efficiently incident on the recording material A.

A filter 78 is arranged between the heat development light source 74 and the reflector 76 and the conveyance path of the recording material A. The filter 78 removes (cuts) light having a wavelength at which the recording material A has sensitivity from the light emitted from the heat development light source 74. As described above, since the recording material A has photosensitivity, if the developing light contains light having a photosensitive wavelength, it is exposed by thermal development. Therefore, it is preferable to use the filter 78 to cut off light having the photosensitive wavelength of the recording material A. The filter 78 may be an ordinary filter manufactured by vapor deposition or the like, and a filter in accordance with the spectral sensitivity characteristics of the recording material A and the wavelength of light emitted from the heat development light source 74 may be appropriately selected and used.

The recording material A conveyed to the thermal developing section 18 by the conveying rollers 70 and the guides 72 is transported by a pair of conveying rollers 82 and 8 which sandwich the heat developing light source 74 in the conveying direction.
While being transported by 4, the developing light emitted from the heat developing light source 74 is irradiated, heated and developed, and the image forming layer 94 is colored to form an image. Here, since the image forming layer 94 of the recording material A and at least one of the layers above and below the image forming layer 94 contain, for example, a dye that absorbs the developing light, the developing light is absorbed by the dye and is preferably converted into heat. Thus, the image forming layer 94 can be efficiently heated by this heat.

The heating in the heat developing section 18 is as follows.
It is necessary to ensure that the amount of heat required for thermal development can be secured according to the type of the recording material A to be used. For example, when the first recording material is used as the recording material A, the image forming layer 94 may be used. When the second and third recording materials are used, the heating is preferably performed so that the temperature is 100 ° C. to 140 ° C., and the temperature of the image forming layer 94 is 85 ° C. to 150 ° C. Further, the heat development time may be adjusted by changing the conveyance speed of the conveyance roller pairs 82 and 84 according to the type of the recording material A. For example, it is preferable that the heat development time is about 10 seconds to 90 seconds for the first recording material, and about 3 seconds to 60 seconds for the second and third recording materials.
In the heat development method of the present invention, if necessary,
A more reliable color development may be performed by using the ordinary thermal development in which the recording material A is heated to perform the development.

The recording material A discharged from the heat development section 18 after the completion of the heat development is discharged to a tray 86 and used as a hard copy for various purposes.

Although the heat development method of the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

[0112]

As described in detail above, according to the heat development method of the present invention, in the image formation using the photosensitive heat development material, the image forming layer is efficiently heated, and the energy efficiency is improved. Thermal development can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of an image recording apparatus using a heat development method of the present invention.

FIG. 2 is a schematic cross-sectional view of an example of a photosensitive heat-developable recording material using the heat development method of the present invention.

FIG. 3 is a schematic diagram of an image exposure unit of the image recording apparatus shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 (Image) recording apparatus 12 (Recording material) supply part 14 Width adjustment part 16 (Image) exposure part 18 Thermal development part 20 Magazine 22, 24 Loading part 26, 28 Suction cup 30, 32 Supply roller pair 34, 36, 44, 60, 62, 64, 66, 68, 8
2, 84 transport roller pair 38, 40, 42, 72 transport guide 46 exposure unit 48 scanning transport means 50 light source 52 exposure controller 54 polygon mirror 56 fθ lens 58 falling mirror 70 transport roller 74 thermal developing light source 76 reflector 78 filter 80 Reflector 86 Tray 92 Support 94 Image forming layer 96 Protective layer 98 Layer A Recording material

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G03F 7/004 514 G03F 7/26 521 7/26 521 B41M 5/26 S

Claims (4)

[Claims] 1. A heat development method for forming an image using a photosensitive heat-developable recording material, comprising irradiating a development light to the photosensitive heat-developable recording material after a latent image is recorded by exposure, and developing by photothermal conversion. A heat development method. 2. The heat developing method according to claim 1, wherein the developing light does not include the photosensitive wavelength of the photosensitive heat-developable recording material. 3. The photothermal conversion is performed by absorbing the developing light contained in at least one of an image forming layer, an upper layer of the image forming layer, and a lower layer of the image forming layer of the photosensitive heat-developable recording material. 3. The heat development method according to claim 1, wherein the heat development is performed with a substance. 4. The thermal developing method according to claim 1, wherein the developing light is far infrared rays or light emitted from a sodium lamp.