JPH10142722A - Recording material and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the recording material adapted to infrared laser beams and good in the absorption efficiency of these beams and low in to background coloring degree and good in recording quality and the provide the recording method using this material and capable of recording a high-quality image. SOLUTION: A recording layer formed on a support contains at least an organic silver slat, the developer of the organic silver salt, a binder, and a cationic dye organic borate, preferably represented by the formula in which D<+> is a cationic dye, and each of R<1> -R<4> is a halogen atom or an alkyl group or the like. It is preferred that the organic silver salt and the cationic dye organic borate are contained by separating them from the developer of the organic silver salt by the partition wall, such as microcapsurles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording material and a recording method using the same, and more particularly to a non-contact infrared laser recording material for recording using infrared laser light and a low energy laser using the same. The present invention also relates to a recording method capable of performing recording with high sensitivity.

[0002]

2. Related Background Art A thermal head is brought into close contact with a surface of a heat-sensitive recording material having a heat-sensitive recording layer (hereinafter referred to as a recording layer) provided on a support, and color is formed by transmitting heat energy to the recording layer directly or through a protective layer. Thermal recording systems for recording images are widely known, and are applied to facsimile machines, printers, and the like.

However, in such a thermal recording method, since the thermal head is brought into close contact with the thermal recording material for scanning, the thermal head is worn or the components of the thermal recording material are scum on the surface of the thermal head. There are drawbacks that a recorded image cannot be obtained correctly due to the adhesion, and that the thermal head is destroyed. In addition, the thermal recording method using such a thermal head has limitations in high-speed control of heating / cooling of the heating elements and in increasing the density of the heating elements due to the structural characteristics of the thermal head. There is a drawback that there is a limit in achieving recording, high-density recording, and high-quality recording.

In order to solve the above-mentioned disadvantages of the thermal recording method using a thermal head, it has been proposed to perform thermal recording at high speed and high density without contact with a thermal recording material using a laser beam. (For example, Japanese Patent Application Laid-Open
No. 3617, JP-A-54-121140, JP-A-57
-11090, JP-A-58-56890, JP-A-5-5680
8-94494, JP-A-58-134791, JP-A-58-145493, JP-A-59-89192,
JP-A-60-205182, JP-A-62-56195
No.).

However, in such a recording method using a laser beam, the recording layer generally does not easily absorb light in the visible and near-infrared regions. There is a drawback that energy is not obtained and it is extremely difficult to produce a small and inexpensive device. Japanese Patent Publication No. 50-774 proposes a method in which microcapsules containing ink are applied to a base paper, and a strong light is applied to eject the ink in the capsule to record on the base paper. Is so low that it has not yet been put to practical use.

Therefore, there have been many proposals for efficiently absorbing a laser beam into a recording layer. In general, a light-absorbing substance suitable for the wavelength of the laser beam is added to the recording layer. ing. In this case, if the light-absorbing substance to be added is not white, the background of the recording material is colored, and only low-quality recording with low contrast can be obtained. However, in general, white light-absorbing substances are many in inorganic compounds, but most of them have low light-absorbing efficiency. On the other hand, organic compounds suitable for absorbing laser light are generally colored to absorb light in the visible light region, and the darker the color, the higher the light absorption efficiency. When added to the recording layer as an absorbing substance, the sensitivity can be increased, but it becomes difficult to reduce the background coloring of the recording paper.

[0007] Therefore, there has been a need for a light-absorbing substance that has a high efficiency of converting light energy to heat energy (light-to-heat conversion efficiency) even in a small amount.

Further, such a heat-sensitive recording material is configured not to develop color with low heat energy in order to maintain a stable storage state. Therefore, considerable heat energy is required to obtain a desired color state. As a result, the dynamic range is narrowed by the threshold value of the heat energy up to color development, and there is a disadvantage that it is difficult to obtain a high-gradation image. In addition, the burden on the apparatus for coloring is considerably increased.

On the other hand, a heat-sensitive recording material to which predetermined heat energy has been applied develops a color in accordance with the heat energy, and an image is visualized. In this case, it is known that the image density of the heat-sensitive recording material after the image is recorded increases with time in a state of storage at room temperature. Therefore, there is a problem that the image density is different between immediately after recording and after a predetermined time has elapsed.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and has high absorption efficiency of infrared laser light, less coloring of the background, and high quality recording. It is possible to provide a recording material for an infrared laser, and to stabilize the density of an image after recording using the recording material, and to sufficiently increase a dynamic range of a laser beam for recording an image or the like. It is an object of the present invention to provide a recording method which can secure a high-gradation and high-precision image or the like.

[0011]

SUMMARY OF THE INVENTION In a recording layer, the absorption efficiency of a laser beam is high, but the absorption of light having a wavelength in the visible light region is small, and the efficiency of converting the energy of the absorbed laser beam into thermal energy is high. By adding a light absorbing substance, not only the recording sensitivity of the recording material can be improved and recording can be performed with a low-output laser, but also the whiteness of the recording material can be improved. And the like are organic borate salts of a cationic dye having a specific structure as the light absorbing substance (hereinafter, appropriately referred to as a specific infrared dye).
Was found to be excellent, and furthermore, it was found that an excellent recording material was obtained by combining an organic silver salt as a color-forming substance.When recording was performed on this recording material using a laser, it was found that extremely good results were obtained. I found that I can do it.

That is, the recording material of the present invention comprises an organic silver salt, an organic silver salt developer and a binder, and preferably has a recording layer containing no silver halide on a support. And an organic borate salt of a cationic dye represented by the following general formula (I).

[0013]

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(Where D is⁺Represents a cationic dye, and R¹,
R^Two, R^ThreeAnd R^FourIs a halogen atom,
Or unsubstituted alkyl group, substituted or unsubstituted aryl
Group, substituted or unsubstituted aralkyl group, substituted or unsubstituted
Substituted alkaryl, substituted or unsubstituted alkenyl
Group, substituted or unsubstituted alkynyl group, substituted or unsubstituted
Substituted alicyclic groups, substituted or unsubstituted heterocycles
Group, substituted or unsubstituted allyl group, substituted or unsubstituted
Represents a silyl group. Where R¹, R^Two, R^ThreeAnd R ^Four
May be the same or different from each other, and these two or more
May combine to form a cyclic structure. In the above invention, the organic silver salt is contained in a solid dispersion state.
Of organic silver salts and organic silver salt developers.
At least one must be microencapsulated and contained
Can also. It is also possible to use a precursor for the developer.
Wear.

Further, in the above invention, it is preferable that the organic silver salt contains a development accelerator.

In the recording material of the present invention, the recording layer contains the organic borate salt of the cationic dye, and the organic borate salt of the cationic dye absorbs the irradiated laser beam to generate radicals. However, these radicals attack silver behenate to form reduced silver (silver nuclei). The silver nuclei are presumed to promote the reaction between the organic silver salt as a color-forming component and the developer of the organic silver salt, but the details of the mechanism do not limit the present invention. JP-A-62-143044
No. describes that the above radical generation was estimated.

In addition, the present inventors may perform a preheating step, a heating step after imagewise laser beam recording, or a preheating step and a heating step after thermal recording when performing image recording using the recording material. As a result, it has been found that the recording density can be improved, the image density after recording can be stabilized, and recording with excellent gradation can be performed.

That is, in the thermal recording method according to the twelfth aspect of the present invention, at least an organic silver salt, a developer of an organic silver salt and a cation represented by the general formula (I) as an infrared absorbing dye are provided on a support. An organic borate salt of a coloring matter, and a recording layer containing a binder is provided, and a recording material that develops a color at a concentration according to the added energy is irradiated with a laser beam modulated according to recording information, A first step of imagewise exposing the recording material to a predetermined coloration temperature and a second step of uniformly heating the entire surface of the imagewise exposed recording material at a predetermined temperature lower than the coloration temperature of the recording material. Process
The recording method according to claim 13, wherein a first step of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than a coloring temperature, and A second step of irradiating the recording material with a laser beam modulated in accordance with recording information and irradiating the recording material imagewise to a predetermined coloring temperature.

Further, according to the recording method of the present invention, at least an organic silver salt, a developer of an organic silver salt, and a cationic compound represented by the general formula (I) as an infrared absorbing dye are provided on a support. A first step in which a recording layer containing an organic borate salt of a dye and a binder is provided, and the entire surface of the recording material that develops color at a concentration corresponding to the applied thermal energy is uniformly preheated to a predetermined temperature lower than the coloration temperature. A second step of imagewise irradiating the preheated recording material to a predetermined coloring temperature with an infrared laser beam modulated according to recording information, and A third step of uniformly heating the entire surface of the recording material at a predetermined temperature lower than the coloring temperature of the recording material.

In the above-mentioned recording material, the recording material further contains a compound having an intramolecularly active halogen group, and is modulated according to recording information with respect to a recording material provided with a recording layer containing no silver halide. A first step of irradiating the entire surface of the recording material imagewise irradiated with a light source of ultraviolet to visible light, and a second step of uniformly exposing the entire surface of the recording material irradiated imagewise with a light source of ultraviolet to visible light. And a third step of uniformly heating the recording material at a predetermined temperature lower than the coloring temperature of the recording material. According to the recording method, the sensitivity is further improved. Before the step, it is preferable from the viewpoint of improving the sensitivity that the method further includes a step of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than the coloring temperature.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the recording material according to the present invention will be described in more detail.

The organic silver salt contained in the recording layer of the recording material for an infrared laser of the present invention is a colorless or white silver salt which is stable to light, and when heated with a developer,
Silver is produced by a redox reaction. Such an organic silver salt is a silver salt of an organic compound having an imino group, a mercapto group or a carboxyl group, and specific examples thereof include the following.

1) Silver salt of an organic compound having an imino group Silver saccharin, silver phthalazinone, silver benzotriazole, etc. 2) Silver salt of an organic compound having a mercapto group or a thione group 3- (2-carbonylethyl) -4-oxy Methyl-4
-Silver salt of thiazoline-2-thione, 3-mercapto-4
Silver salts of organic compounds having a carboxyl group, such as silver stearate and silver behenate.

Among these, from the viewpoints of being white and stable to light, having excellent moisture resistance, being usable in combination with a mild developer, and being known for excellent color toning agents, Silver behenate is most preferred.

In the recording material for infrared laser of the present invention, it is preferable to use a desalted and purified organic silver salt from the viewpoint of recording a high density image using a high density organic silver salt. Here, desalination purification means, for example, when preparing an organic silver salt by adding silver nitrate to a salt of an organic acid formed by adding an alkali to an organic acid, a nitrate salt by-produced by the addition of the silver nitrate Is to be removed from the system. Such desalting purification is preferably performed by an ultrafiltration method using a semipermeable membrane that allows the passage of nitrate but not the organic silver salt, or a centrifugation method.

In the recording layer of the recording material for an infrared laser according to the present invention, a latent image is formed upon exposure to light, and a photoreceptivity capable of rapidly performing a reduction reaction to an organic silver salt, that is, development. When the silver halide is contained adjacent to the organic silver salt, the recording material of the present invention also has a function as a photosensitive recording material for performing recording by a laser beam. The silver halide in this case is appropriately selected from known silver halides such as silver chloride, silver bromide, silver chlorobromide, silver iodide, silver iodobromide, silver chloroiodobromide and the like. be able to.

When the silver halide is contained adjacent to the organic silver salt, the silver halide is contained in the system in which the organic silver salt is present, but a part of the organic silver salt is halogenated by adding a silver halide forming agent. It is preferable to contain it by changing it to silver.

As the silver halide forming agent, CaB
inorganic halides such as r ₂ , KBr, KCl and HBr; onium halides such as NH ₄ Br and NH ₄ Cl;
Examples thereof include halogen-donating compounds such as halogenated carbon and N-halides such as N-bromosuccinimide.

When silver halide is used in combination, the content is preferably 1 to 30 mol% based on the organic silver salt.

Next, the organic silver salt developer will be described.
The developer used in the recording material of the present invention is a reducing agent having an action of reducing an organic silver salt to generate silver when heated, and rapidly reacting at a developing temperature to reduce the image. Characteristics such as not affecting the color tone are required.

Examples of such a developer include hydroxycoumarone or hydroxycoumarans, sulfamidophenols or sulfamidonaphthols, hydradones, hirooxamic acids, bis-β-naphthols, and indane-1,3. -Diones, aminophenols or aminonaphthols, pyrazolin-5-ones, hydroxylamines, reductones, hydrazines, hydroquinones, bisphenol A, bisphenol B
Such as polyphenols, gallic acid, gallic acid ester,
Phenylenediamines, hydroxyindanes, 1,4
-Dihydroxypyridines, amide oximes, hydroxy-substituted aliphatic carboxylic acid aryl hydrazides, N-
Hydroxyureas, phosphonamidophenols, phosphonamidoanilines, α-cyanophenylacetic esters, sulfonamidoamilines and the like, among these, each compound represented by the following formula, octyl gallate, It is preferable to use propyl gallate, ethyl gallate or methyl gallate.

[0032]

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The method for solid dispersion of the organic silver salt in the present invention includes, for example, a water-soluble polymer compound such as an organic silver salt and polyvinyl alcohol, and, if necessary, a color tone agent, an antifoggant, a dispersant, and water. And disperse it to several microns or less by a ball mill, sand mill or the like. On the other hand, the developer is similarly solid-dispersed or completely dissolved in an aqueous solution such as polyvinyl alcohol. The respective liquids thus obtained are blended to prepare a solid dispersion coating liquid, which is coated on a support to obtain a recording material.

In the present invention, from the viewpoint of preventing the reduction reaction between the organic silver salt and the developer at room temperature to extend the shelf life of the infrared laser recording material and to reduce the fogging with time, the organic silver salt is used. Preferably, at least one of the organic silver salt developer and the organic silver salt developer is encapsulated in microcapsules. When only one of the organic silver salt and the developer of the organic silver salt is microencapsulated, the other is used by dispersing it in a solid, completely dissolved in an aqueous solution of polyvinyl alcohol or the like, or dissolved in an organic solvent. After being converted into an oil phase, the oil phase can be mixed with an aqueous phase containing a water-soluble polymer and used in the form of an emulsified dispersion. In the latter case, the recording layer can be made transparent. When both the organic silver salt and the organic silver salt developer are microencapsulated, it is preferable that these are encapsulated in separate microcapsules.

That is, the infrared absorbent according to the present invention is supposed to generate radicals upon irradiation with a laser beam (JP-A-62-143044). Therefore, in order to prevent the generated radical from reacting with the reducing agent (developer) before forming a predetermined silver nucleus by reacting with the organic silver salt, the infrared absorbing agent and the organic silver salt are combined with the developer. Is preferably encapsulated in a microcapsule and separated by a capsule wall.In addition to microencapsulation, as a core-shell type latex, and in a recording layer having a plurality of layers, a layer containing each is an intermediate layer. And the like, and are preferably separated by an isolating membrane.

Microcapsules usable in the present invention include:
It is a thermo-responsive microcapsule that isolates a substance contained at room temperature, is not destroyed by pressure, heat, or the like at the time of heating, and makes the wall of the microcapsule material-permeable.

As a method for producing such microcapsules, known production methods such as an interfacial polymerization method, an internal polymerization method, and an external polymerization method can be employed. In particular, an organic silver salt or an organic silver salt can be used. An oil phase component obtained by adding a capsule wall material (polymer material) to a core material obtained by dissolving or dispersing a developer in an organic solvent is emulsified in an aqueous solution in which a water-soluble polymer is dissolved. It is preferable to adopt an interfacial polymerization method in which a wall made of the polymer of the capsule wall material is formed around the capsule wall.

As the organic solvent, it is preferable to use a non-aqueous solvent having a boiling point of 150 ° C. or less, such as a carboxylic acid ester such as ethyl acetate, butyl acetate and isoamyl acetate, toluene, xylene and phosphate ester.

The reactant forming the capsule wall material is added inside the oil droplet and / or outside the oil droplet.

Specific examples of the capsule wall material include polyurethane, polyurea, polyamide, polyester, polycarbonate, urea-formaldehyde resin, polyamic acid, polystyrene, styrene methacrylate copolymer, styrene-acrylate copolymer and the like.
Preferred capsule wall materials are polyurethane, polyurea, polyamide, polyester, and polycarbonate, and polyurethane and polyurea are preferred because capsules that are hard to break are obtained. These polymer substances can be used in combination of two or more kinds.

Specific examples of the water-soluble polymer include gelatin, polyvinylpyrrolidone, and polyvinyl alcohol.

For example, when polyurea or polyurethane is used as a capsule wall material, (a) a polyvalent isocyanate such as diisocyanate, triisocyanate, tetraisocyanate, or polyisocyanate prepolymer; and (b) diamine , Triamine, tetraamine and other polyamines, prepolymers containing two or more amino groups, piperazine or its derivatives, polyhydric alcohols and the like, or water in an aqueous solvent by an interfacial polymerization method to easily form microcapsule walls. Can be formed. The microcapsules in this case are preferable because their walls are dense.

For the composite wall composed of polyurea and polyamide or the composite wall composed of polyurethane and polyamide, for example, the pH of an emulsifying medium as a reaction solution is adjusted by using polyisocyanate and acid chloride or polyamine and polyhydric alcohol. Thereafter, it can be prepared by heating. For details of the method for producing a composite wall composed of these polyurea and polyamide, see JP-A-58-1983.
-66948. The capsule made of polyamic acid is formed, for example, by an interfacial reaction between a polystyrene-maleic anhydride copolymer and a polyvalent amine.

Particularly preferred wall materials of the microcapsules used in the recording material for infrared laser of the present invention include the following isocyanate compounds.

The isocyanate-based compounds used herein include known isocyanate monomers (1) urethane-modified, (2) allophanate-modified, (3) isocyanurate-modified, (4) buret-modified, and (5) ) Modified carbodiimides, (6) modified products such as blocked isocyanates, and (7) polymeric MDI,
Linear polymer of 4'-diphenylmethane diisocyanate (MDI).

As the isocyanate monomer forming the modified product, tolylene diisocyanate (TDI), 4,4
4'-diphenylmethane diisocyanate (MDI),
Xylylene diisocyanate (XDI), naphthylene diisocyanate (NDI), paraphenylene diisocyanate (PPDI), tetramethyl xylylene diisocyanate (TMXDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), isophorone diisocyanate (IP
DI), lysine diisocyanate (LDI), isopropylidene bis (4-cyclohexyl isocyanate)
(IPC), hydrogenated xylylene diisocyanate (hydrogenated X
DI), cyclohexyl diisocyanate (CHD
I) and tolidine diisocyanate (TODI). The structure of this isocyanate monomer is shown below, but the isocyanate monomer used in the present invention is not limited to these. These are described in detail, for example, in "Synthesis, blending, functionalization and application development of latest polyurethane" (Technical Information Association, 1989).

[0047]

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[0048]

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These isocyanate monomers are used after being modified into various isocyanate modified products as described above for the purpose of improving undesirable physical properties such as toxicity, controlling the reaction rate, and improving the mixing ratio. Can be Next, the modified form will be described. (1) The urethane-modified product is obtained by modifying an isocyanate monomer (or diisocyanate) with a shortage of polyol. (2) The modified allophanate is formed by adding an isocyanate group to a urethane group. (3) The modified isocyanurate has an isocyanurate ring in the molecule and tends to have improved heat resistance. (4) The modified buret is a compound in which an isocyanate group is added to a urea bond, and is a compound from which free isocyanate is removed. (5) In the modified carbodiimide, a carbodiimide bond is generated from a 2 mol isocyanate group by a decarbonation reaction. Furthermore, after uretonimine is formed when the isocyanate is added, carbodiimide and uretonimine coexist in equilibrium. (6) Blocked isocyanate is obtained by reacting various blocking agents to temporarily mask the activity of the isocyanate group.
Phenolic blocking agents such as xylenol, oximes,
Active hydrogen compounds such as lactams and alcohols are exemplified.

Specific examples of the capsule wall material of the recording material for infrared laser of the present invention include isocyanate compounds represented by the following formulas (a) to (k) in view of safety and availability. .

[0051]

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[0052]

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The reactant forming the capsule wall material is preferably heated after emulsification and dispersion. The heating conditions are preferably 30 to 80 ° C. for 30 minutes to 4 hours. If the temperature is lower than 30 ° C., the reaction requires a long time and the reaction proceeds only incompletely. When the temperature exceeds ℃, it becomes difficult to control the reaction, which is not preferable.

For example, when an isocyanate compound is used as a capsule wall material, an oil phase component obtained by further adding at least one isocyanate compound to a dispersion obtained by dispersing an organic silver salt in an organic solvent as described above. After being added to an aqueous solution containing a water-soluble binder such as gelatin,
Stirring is performed to obtain a dispersion in which the oil phase component is dispersed in an aqueous solution, and the entire dispersion is heated to, for example, about 40 to 90 ° C. to form a wall material of microcapsules.

At this time, the average particle size of the obtained microcapsules is preferably 0.1 to 3.0 μm,
More preferably, it is 0.2 to 1.2 μm. By controlling the particle diameter in the above range, the transparency of the recording layer is improved, and there are advantages such that an image can be observed with transmitted light in a sharkstain.

Next, the infrared absorbing dye used in the recording material of the present invention will be described. The compound used as an infrared absorbing dye in the recording material for an infrared laser of the present invention is a compound having a maximum absorption wavelength in a wavelength region of 750 to 1100 nm, and is preferably a cationic compound represented by the following general formula (I). It is an organic borate salt compound of a dye.

The organic borate compound itself has been known as an auxiliary for a photosensitive recording material using silver halide, but its use is limited because it is acid-decomposable. In the present invention, by combining a specific cationic dye with this organic borate salt-based compound, for example, it becomes possible to use in combination with an organic silver salt reducing agent such as silver behenate, and a thermosensitive recording material to which a laser is applied And the like, which can be used as a sensitivity improving agent for a wide range of recording materials.

The organic borate salt-based compound of a cationic dye represented by the following formula (I) useful as an infrared absorbing dye used in combination with an organic silver salt in the present invention will be described in detail.

[0059]

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Here, D ⁺ represents a cationic dye, and R ^+
1 , R ² , R ³ and R ⁴ may be the same or different and are each a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted group. Alkaryl group, substituted or unsubstituted alkenyl group, substituted or unsubstituted alkynyl group, substituted or unsubstituted alicyclic group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted allyl group, substituted or It is a group selected from unsubstituted silyl groups, and two or more of R ¹ , R ² , R ³ and R ⁴ may combine to form a cyclic structure.

The cationic dye represented by D ⁺ includes:
It is preferably a dye selected from cationic methine dyes, polymethine dyes, triarylmethane, indoline, azine, xanthene, oxazine and acridine dyes.

Further, the cationic dye is preferably a dye selected from cationic cyanine, hemicyanine, rhodamine and azamethine dyes.

The organic borate salt of the organic cationic dye represented by the general formula (I) uses an organic cationic dye and an organic boron compound anion, and is disclosed in EP 223,583.
It can be obtained by referring to the method described in No. 7A1.

The general formula (I) which can be used in the present invention
The cationic dye (spectral sensitizing dye) represented by D ⁺ in the wavelength range is 750 nm or more, preferably 750 nm.
Any organic cationic dye having an absorption peak in the wavelength region of １1100 nm can be preferably used.
This spectral sensitizing dye has no coloring in the visible region,
It is desirable that the following optical density is 0.2 or less. If the coloration in the visible region is strong, it is not preferable because clear color due to the combined dye or sample becomes turbid.

Examples of the organic cationic dyes usable in the present invention include cationic methine dyes, cationic carbonium dyes, cationic quinone imine dyes, cationic indoline dyes, and cationic styryl dyes. As the methine dye, preferably a polymethine dye, a cyanine dye, an azomethine dye,
More preferably cyanine, carbocyanine, dicarbocyanine, tricarbocyanine, hemicyanine and the like, as the cationic carbonium dye, preferably a triarylmethane dye, xanthene dye, alicidine dye,
More preferably rhodamine and the like, as the cationic quinone imine dye, preferably a dye selected from azine dyes, oxazine dyes, thiazine dyes, quinoline dyes, thiazole dyes and the like, and these are used alone or in combination of two or more. Can be used.

Many organic cationic dye compounds having an absorption peak in the wavelength region of 750 nm or more are known. For example, "Functional dye chemistry"
1981, CMC Publishing Co., pp. 393-416, and "Coloring Materials", 60 [4] 212-224 (1987).

Specific examples of the organic oxygen compound anion salt of the organic cationic dye compound represented by formula (I) of the present invention are shown below. However, the effects of the present invention are not limited to the following compounds.

[0068]

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[0069]

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[0070]

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The specific infrared dye used in the present invention has a function of improving the absorption efficiency of infrared laser, and it is preferable that the site to be contained is close to the organic silver salt.

Further, in the present invention, an auxiliary such as a compound having an active halogen group in a molecule represented by the following general formula (II) or (III) may be appropriately combined with the infrared absorbing dye. Can be used.

[0073]

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In the general formula (II), X represents a halogen atom. Y ¹ is —CX ₃ , —NH ₂ , —NHR, —N
R ₂ represents —OR. Here, R represents an alkyl group, a substituted alkyl group, an aryl group, or a substituted aryl group. Also,
Y ² represents -CX _3, an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, a substituted alkenyl group. The substituent may be the general formula (II) itself.

[0075]

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In the general formula (III), 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.

[0077]

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

The compound represented by the general formula (II) is described in Written by Wakabayashi et al., Bulletin of Chemical Society Japan (Bull, Chem, Soc, Japan) 42, 292.
Compounds described on page 4 (1969), specifically, for example, 2-phenyl-4,6-bis (trichloromethyl)
-S-triazine, 2- (p-chlorophenyl) -4,
6-bis (trichloromethyl) -S-triazine, 2-
(P-tolyl) -4,6-bis (trichloromethyl)-
S-triazine, 2- (p-methoxyphenyl) -4,
6-bis (trichloromethyl) -S-triazine, 2-
(2 ′, 4′-Dichlorophenyl) -4,6-bis (trichloromethyl) -S-triazine, 2,4,6-tris (trichloromethyl) -S-triazine, 2-methyl-4,6-bis ( Trichloromethyl) -S-triazine, 2-n-nonyl-4,6-bis (trichloromethyl) -S-triazine, 2- (α, α, β-trichloroethyl) 4,6-bis (trichloromethyl)- S-triazine and the like can be mentioned. In addition, British Patent 138849
No. 2, for example, 2-styryl-4,
6-bis (trichloromethyl) -S-triazine, 2-
(P-methylstyryl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxystyryl) -4,6-bis (trichloromethyl) -S-triazine, 2- (p-methoxy Styryl) -4-amino-6
-Trichloromethyl-S-triazine, etc.
Compounds described in the specification of 133428, for example, 2-
(4-methoxy-naphth-1-yl) -4,6-bis-
Trichloromethyl-S-triazine, 2- (4-ethoxy-naphth-1-yl) -4,6-bis-trichloromethyl-S-triazine, 2- [4- (2-ethoxyethyl) -naphth-1- Yl] -4,6-bis-trichloromethyl-S-triazine, 2- (4,7-dimethoxy-
Naphth-1-yl] -4,6-bis-trichloromethyl-S-triazine, 2- (acenaphth-5-yl)-
4,6-bis-trichloromethyl-S-triazine and the like,
Compounds described in German Patent No. 3337024, for example, compounds represented by the following structural formula can be mentioned.

[0080]

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As other compounds, compounds represented by the following structural formulas can be used as auxiliaries.

[0082]

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Further, F. C. Journal of Organic Chemistry by Schaefer et al. (J.O.
rg. Chem. 29, 1527 (1964)
The compounds described, for example, 2-methyl-4,6-bis (tribromomethyl) -S-triazine, 2,4,6-tris (tribromomethyl) -S-triazine, 2,4,6
-Tris (dibromomethyl) -S-triazine, 2-amino-4-methyl-6-tribromomethyl-S-triazine, 2-methoxy-4-methyl-6-trichloromethyl-S-triazine and the like. .

Further, there may be mentioned compounds described in Japanese Patent Application No. 60-198868, for example, compounds represented by the following structural formulas.

[0085]

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[0086]

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When the compound represented by the general formula (II) is used as an auxiliary in the recording material of the present invention, Y ¹ is -CX ₃
It is particularly preferred to use a compound of the formula

The compound of the general formula (II) used in the present invention can be synthesized by a method known to those skilled in the art. Specifically, Bulletin of Chemical Society Japan (Bull, Chem, Soc, Jpn) Vol. 42, p. 2924 (196)
9 years), for example, a compound having the following structure can be obtained.

[0089]

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Further, referring to the description of DE 2718259 (application number), for example, a compound having the following structure can be obtained.

[0091]

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Further, referring to US Pat. No. 4,619,998, for example, a compound having the following structure can be obtained.

[0093]

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Can be obtained. In the present invention, as the compound represented by the general formula (III) having an active halogen group used as an auxiliary agent for an infrared absorbing dye, a compound described in JP-B-51-8330, specifically, For example, carbon tetrachloride, carbon tetrabromide, iodoform, p-nitro-α, α, α-tribromoacetophenone, ω, ω, ω-tribromoquinaldine, tribromomethylphenylsulfone, trichloromethyl Phenyl sulfone and the like can be mentioned. In addition, Tokiko 49-12
No. 180, for example, compounds having the following structure,

[0095]

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[0096]

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Further, there may be mentioned the compounds described in JP-A-60-138538, for example, compounds having the following structures.

[0098]

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The following are examples of compounds having an active halogen group which can be preferably used in the present invention. It goes without saying that the invention is not limited to these compounds.

[0100]

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[0101]

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In the present invention, the infrared absorbing dye represented by the general formula (I) and the general formula (II) or the general formula (III)
It is preferable that the compound represented by the formula (1) is added in the range of 0.01 to 50% by weight with respect to silver behenate.

The compound represented by the general formula (II) or (III) is used in an amount of 0.01 to 20 mol, preferably 0.1 to 20 mol, per 1 mol of the infrared absorbing dye represented by the general formula (I).
It is preferable to add 10 mol.

The recording material of the present invention is highly sensitive and sensitive to infrared light. Further, as an auxiliary for promoting the formation of a latent image, a reducing agent such as an oxygen scavenger (Oxygens) is used.
cavenger) and an active hydrogen donor chain transfer agent,
Other compounds can be used in combination.

Oxygen scavengers which have been found to be useful in the recording materials of the present invention as auxiliaries for accelerating the formation of latent images are readily available from phosphines, phosphonates, phosphites, stannous salts and oxygen. Other compounds that are oxidized to: Specifically, for example, N-phenylglucin, trimethylbarbituric acid, N, N-dimethyl-
2,6-diisopropylaniline, N, N, N-2,
4,6-pentamethylaniline and the like. Further, the following thiols, thioketones, lofin dimer compounds, iodonium salts, sulfonium salts, azinium salts, organic peroxides, and the like are also useful as auxiliaries.

As thiols,

[0107]

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As thioketones,

[0109]

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[0110]

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The loffin dimer compounds include:

[0112]

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The iodonium salts include

[0114]

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As the sulfonium salts,

[0116]

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The azinium salts include

[0118]

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As the organic peroxide,

[0120]

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And the like can be used. The water-soluble binder used in the present invention has a function of binding the developer and the microcapsules contained in the recording layer and a function of adhering the recording layer to the support. Examples of such a water-soluble binder include gelatin and / or a gelatin derivative (eg, phthalated gelatin), polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose,
Water-soluble polymers such as hydroxypropylcellulose, arabic gum, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylate, and various emulsions such as ethylene-vinyl acetate copolymer. Can be.

The amount of the binder used is preferably 0.5 to 5 g / m ² in terms of solid content.

In the present invention, from the viewpoint of accelerating the reduction reaction between the organic silver salt and the developer at the time of heating, adjusting the color tone of the image and performing rapid development, a development accelerator (color tone agent) is used.
Is preferably contained in the recording layer.

The development accelerator is preferably used when the resulting image is desired to be a dark image, especially a black image. The amount used ranges from about 0.0001 mol to about 2 mol, preferably from about 0.0005 mol to about 1 mol, per 1 mol of the organic silver salt. Effective development accelerators vary with the organic silver salt and developer used, but the most common development accelerators are heterocyclic organic compounds containing at least two heteroatoms, wherein the heterocycle contains At least one nitrogen atom is present.

These are described, for example, in US Pat.
No. 0,254. Specific examples of such a development accelerator include, for example, phthalazone (phthalazinone), anhydrous phthalates, 2-acetylphthalazinone,
2-phthalylphthalazinone and others, JP-A-50-67
Examples include substituted phthalazinones described in JP-A-132, which are preferably used in the present invention.

Examples of other effective development accelerators include pyrazolin-5-ones, cyclic imides, and quinazolinones as described in JP-A-46-6077. Specific examples of these include phthalimide, N-hydroxyphthalimide, N-potassium phthalimide, and silver phthalimide. Alternatively, phthalazinones are also effective as development accelerators.

Other effective development accelerators are disclosed in
And mercapto compounds as described in JP-A Nos. 9-5019 and 49-5020. Other examples include oxazinediones described in JP-A-50-2542, phthalazinediones described in JP-A-50-67641, and 58-114217.
Uracils as described in U.S. Pat. No. 3,782,941 as described in U.S. Pat. No. 3,782,941.
Hydroxyhydroxyphthalimides, as described in West German Patent Application Publication Nos. 2,140,406, 2,141,063 and 2,220,597.
Substituted phthalimides, West German Patent Application Publication No. 2,22
Phthalazinone derivatives, such as those described in U.S. Pat. No. 0,618, can be used as well.

In the recording material for infrared laser of the present invention, it is preferable to further take the following measures from the viewpoint of preventing thermal fogging and stabilizing the background after image formation.

First, it is well known that mercury compounds are very effective in preventing thermal fog and stabilizing the background after image formation. However, from the viewpoint of environmental pollution, it is difficult to use these compounds. Since it is not preferable, in the present invention, JP-A-49-10724, JP-A-48-2842,
N, as described in JP-A-48-8194,
It is preferred to use N-halogeno compounds such as -halogenosuccinimide, N-halogenoacetamide, N-halogenoxazolinone, N-halogenobenzotriazole, and N-halogenobenzimidazole.

Also, US Pat. No. 3,645,739, JP-A-49-125016, and JP-A-49-1307.
No. 20, 50-57619, 50-39264, etc .; higher fatty acids; arylsulfonates such as tetrahalogenophthalic acid or anhydride, benzenesulfonic acid, p-toluenesulfonic acid; benzene Use of arylsulfinic acids such as sulfinic acid and p-toluenesulfinic acid or salts thereof; lithium salts of higher fatty acids such as lithium myristate, lithium stearate, lithium behenate, lithium palmitate and lithium laurate as acid stabilizers. be able to.

Other acid stabilizers include salicylic acid and p-
Alkyl-substituted benzoic acids such as hydroxybenzoic acid, tetrabromobenzoic acid, tetrachlorobenzoic acid, p-acetamidobenzoic acid, pt-butylbenzoic acid, phthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, dicitric acid, 5 '5'-Methylenebissalicylic acid, citric acid, tartaric acid, oxalic acid, boric acid, phosphoric acid, pyrophosphoric acid and the like are also effective. These acid stabilizers not only prevent thermal fogging, but also have the effect of preventing background discoloration upon exposure to white light after image formation and improving shelf life.

Other compounds effective for preventing thermal fogging and preventing photodiscoloration include benzotriazole and its derivatives, tetrazole and its derivatives, thiouracils,
Compounds such as -phenyl-5-mercaptotetrazole, azole thioethers or blocked azolethiones disclosed in JP-A-47-318, tetrazolylthio compounds disclosed in U.S. Pat. No. 3,700,457; 3,707,377 and 4,
No. 108,455, photosensitive halogeno organic oxidizing agents; polybrominated organic compounds such as 2,4-bis (tribromomethyl) -s-triazine and polybromoalkylsulfonyl compounds shown in 3,874,946. compounds, the 4,546,075 trihalomethyl tetrazole derivatives as shown in JP, trihalomethyl benzimidazole and benzoxazole counterparts, or benzothiazole counterparts, R ^a -CX disclosed in JP-a-59-57234 A compound represented by _2- ^Rb (X represents halogen: ^Ra , ^Rb represents a group such as acyl, oxycarbonyl, oxysulfonyl, alkylsulfonyl, allylsulfonyl, aralkylsulfonyl, carboxyl, sulfo, sulfamoyl, etc.), US Patent No. 4,465,761
No. 4,452,88.
2-trihalomethyl oxazole derivative shown in No. 5, a heterocyclic compound having a trihalomethyl group shown in 4,756,999, and a compound represented by the following formula disclosed in European Patent No. 622,666. Is valid.

[0133]

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In the above formula, R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a thioalkyl group, a perhalogenated alkyl group,
Or a cycloalkyl group.

The effects of the present invention are particularly remarkable when the above-mentioned heat fogging photodiscoloration inhibitor is used in combination with a thermoresponsive capsule.

In order to swell the microcapsule wall at the time of infrared laser irradiation and / or thermal development, a sensitizer may be added in an emulsified or solid state to increase the thermal sensitivity.

As the sensitizer, a plasticizer having a melting point of 50 ° C. or higher, preferably 150 ° C. or lower and being solid at ordinary temperature can be selected from those called polymer plasticizers used as the capsule wall material. . For example, when the capsule wall material is made of polyurea or polyurethane, a hydroxy compound, a carbamate compound, an aromatic alkoxy compound, an organic sulfonamide compound, an aliphatic amide compound, an arylamide compound and the like are preferably used.

Further, in the present invention, a coloring aid can be used. The color-forming auxiliary that can be used in the present invention is a substance that increases the color density at the time of heat development or lowers the minimum color-forming temperature, and has an effect of lowering the softening point of the capsule wall, and the like. This is for creating a situation in which the developer easily reacts.

Examples of the coloring aid include phenol compounds, alcoholic compounds, amide compounds, and sulfonamide compounds. Specific examples include p-tert-octylphenol, p-benzyloxyphenol, phenyl p-oxybenzoate, and the like. Examples thereof include compounds such as benzyl carbanilate, phenethyl carbanilate, hydroquinone dihydroxyethyl ether, xylylene diol, N-hydroxyethyl-methanesulfonic acid amide, and N-phenyl-methanesulfonic acid amide. These may be contained in the core substance in such a manner as not to adversely affect the recording characteristics, or may be added to the outside of the microcapsule as an emulsified dispersion.

The support used in the present invention may be transparent or opaque. Opaque supports include paper,
Examples thereof include synthetic paper, paper obtained by laminating a polymer film on paper, aluminum vapor-deposited base, and polymer film coated with a white pigment. In this case, it is preferable to use a support having high reflectivity of laser light so that the laser light is irradiated from the recording layer side and is efficiently absorbed by the recording layer.

On the other hand, as the transparent support, it is preferable to use a support that does not absorb the laser beam to be irradiated and has dimensional stability that does not deform due to heat generated during laser beam irradiation. In this case, recording can be performed by irradiating a laser beam through the transparent support. The thickness of the support is 10 μm to 200 μm.

Examples of such a transparent support include polyester films such as polyethylene terephthalate, polyethylene naphthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate film, and polyolefins such as polystyrene film, polypropylene film and polyethylene film. Examples thereof include a film, a polyimide film, a polyvinyl chloride film, a polyvinylidene chloride film, a polyacrylic acid copolymer film, and a polycarbonate film. These can be used alone or in combination. Films that can be used as the transparent support preferably have a haze (degree of cloudiness) of 3% or less.

As the support used in the present invention, a polyester film which has been subjected to heat treatment and antistatic treatment is particularly preferred.

The method for producing the film is not particularly limited as long as the above object can be achieved. Specific examples include a method of producing a film by heating and melting, extruding, cooling, solidifying, stretching, and heat setting.

The support may contain inorganic fine particles, an antioxidant, an antistatic agent, a dye and the like as long as the object of the present invention is not hindered.

The inorganic fine particles that can be used here include I
Group A, IIA, IVA, VIA, VIIA, VIII, I
Group B, IIB, IIIB, IVB, oxides, hydroxides, sulfides, nitrides, halides, carbonates, acetates, phosphates, phosphites, organic carboxylate of each element, Silicates,
Examples include titanates, borates and their hydrated compounds, composite compounds centered on them, and natural mineral particles.
Specifically, Group IA element compounds such as lithium fluoride, borax (sodium borate hydrate), magnesium carbonate, magnesium phosphate, magnesium oxide (magnesia), magnesium chloride, magnesium acetate, magnesium fluoride, magnesium titanate, silicate Magnesium, magnesium silicate hydrate (talc), calcium carbonate, calcium phosphate, calcium phosphite, calcium sulfate (gypsum), calcium acetate, calcium terephthalate, calcium hydroxide, calcium silicate, calcium fluoride, calcium titanate, titanic acid Group IIA element compounds such as strontium, barium carbonate, barium phosphate, barium sulfate and barium phosphite, titanium dioxide (titania), titanium monoxide, titanium nitride, zirconium dioxide (zirconia), and zirconium oxide IVA Group element compound, molybdenum dioxide,
Group VIA element compounds such as molybdenum trioxide, molybdenum sulfide, manganese chloride, manganese acetate and the like; Group VIII element compounds such as cobalt chloride and cobalt acetate; Group IB element compounds such as cuprous iodide; Group IIB element compounds such as zinc oxide and zinc acetate; aluminum oxide (alumina); aluminum oxide; aluminum fluoride; group IIIB element compounds such as aluminosilicate (alumina silicate, kaolin, kaolinite); silicon oxide (silica, silica gel) ), Graphite, carbon, graphite, glass etc.
Particles of a group IVB element compound, natural minerals such as kernalite, kainite, mica (mica, kinmo), and virose ore. Above all, from the viewpoint of handleability,
Preferred are silica, talc, titania, alumina, calcium carbonate, calcium oxide, calcium chloride and the like, and mixtures thereof. Examples of the organic fine particles include fine particles such as cross-linked polystyrene and cross-linked polymethyl methacrylate. Antioxidants, antistatic agents, dyes, and the like can be blended with known additives for resins according to the purpose.

[0147] Further, the rear surface of polyoxyethylene-based support, sulfonic acid-based surfactant, and / or volume resistivity of 10 ⁰ ~10 ⁵ Ω · cm of ZnO, TiO _2, SnO
₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, Ba
A back layer containing at least one kind of crystalline metal oxide selected from O and MoO ₃ or fine particles of these composite oxides can be provided. These components may be contained in a suitable binder to form a back layer. The support on which such a back layer is formed has an antistatic ability with excellent practical various performances.

In the present invention, when a polymer film or a paper laminated with the polymer film is used as a support, or when a transparent support is used, in order to enhance the adhesiveness between the support and the recording layer, these are used. It is preferable to provide an undercoat layer between the layers.

As the material for the undercoat layer, gelatin, synthetic polymer latex, nitrocellulose, acrylate copolymer, polyvinylidene chloride, styrene / butadiene rubber, aqueous polyester, etc. are used. The coating amount of the undercoat layer is preferably in the range of ^{0.1g / m 2 ~2.0g / m 2} , preferably in the range particularly ^{0.2g / m 2 ~1.0g / m 2} .

The undercoat layer is swelled by water contained in the recording layer when the recording layer is coated thereon, and may deteriorate the image quality of the recording layer. Therefore, the undercoat layer is cured using a hardener. It is desirable.

As the hardener, for example, JP-A-2-141
No. 279 can be mentioned. The addition amount of these hardeners is in the range of 0.20% by weight to 3.0% by weight based on the weight of the undercoat layer, and an appropriate addition amount is selected according to the coating method and the desired degree of curing. be able to.

Depending on the hardener used, if necessary, caustic soda may be further added to adjust the pH of the solution to an alkaline side, or the pH of the solution may be adjusted to an acidic side by citric acid or the like. Further, an antifoaming agent may be added to eliminate bubbles generated at the time of application, or an activator may be added to improve the leveling of the liquid and prevent the generation of coating streaks.

Further, before applying the undercoat layer, it is desirable to activate the surface of the support by a known method. As the method of the activation treatment, an etching treatment with an acid, a flame treatment with a gas burner, a corona discharge treatment, a glow discharge treatment, or the like is used. From the viewpoint of cost or simplicity, US Pat. No. 075,
Nos. 2,846,727 and 3,549,406
No. 3,590,107 and the like are most preferably used.

In the present invention, in order to protect the recording layer from sticking and solvents, it is preferable to provide a protective layer containing a pigment on the recording layer.

Examples of such pigments include mica, talc,
Calcium carbonate, zinc oxide, titanium oxide, aluminum hydroxide, kaolin, talc, fluorite, synthetic silicate, amorphous silica, urea formalin resin powder and the like,
Among these, calcium carbonate, aluminum hydroxide, kaolin, silica, mica and talc are particularly preferred.

The protective layer in the present invention may contain aged polyvinyl alcohol, carboxy-modified polyvinyl alcohol, silica-modified polyvinyl alcohol, etc. as a binder from the viewpoint of retaining the pigment and improving transparency. preferable.

The coating solution for a protective layer (referred to as a protective layer solution) in the present invention is obtained by mixing a pigment with the above solution of the binder. Depending on the purpose, zinc stearate, calcium stearate, paraffin wax, polyethylene wax may be used. And various auxiliaries such as a fluorescent brightener, a crosslinking agent, a sulfosuccinic acid-based alkali metal salt and a fluorine-containing surfactant, and a polyoxyethylene surfactant.

The recording material for an infrared laser of the present invention is prepared, for example, by preparing an organic silver salt solid dispersion represented by the general formula RCOOAg or a microcapsule liquid containing an organic silver salt.
Further, a developer of an organic silver salt, an infrared absorbing dye and other additives are added to prepare a coating solution for a recording layer, and the coating solution for a protective layer as described above is prepared, and on a support, Bar coating, blade coating, air knife coating, gravure coating,
Apply and dry by a coating method such as roll coating, spray coating, dip coating, etc.
25 g / m ² recording layer, 0.2 to 7 g / m ² in terms of solid content
It is manufactured by providing ^two protective layers.

The coating amount of the organic silver salt and the developer is preferably 0.5 to 3.0 g / m ² , more preferably 0.8 to 2.0 g / m ² , as the Ag component in the recording layer. Is preferred. It is desirable that the recording layer is applied so that the thickness of the recording layer is 1 to 20 μm.

The coating liquid used in the present invention contains a pigment dispersant, a thickener, a flow modifier, and the like, as long as the properties of the present invention are not impaired.
An antifoaming agent, a defoaming agent, a release agent, a coloring agent, a wax, a hardener, and the like can be appropriately compounded as needed.

Further, if necessary, a back coat layer may be provided on the surface of the support of the recording material for infrared laser which is opposite to the color forming layer. As the back coat layer, any known one can be used as the back coat layer of the recording material for infrared laser.

The laser beam used in the present invention has a wavelength in the near infrared region. Specific examples thereof include a helium-neon laser, an argon laser, a carbon dioxide laser, a YAG laser, and a semiconductor laser.

Next, the thermal recording method of the present invention will be described. When the recording material for infrared laser of the present invention is used, the absorption efficiency of infrared laser light is high and the coloring of the background is small, so that an excellent image can be formed even with low energy laser light. By applying the recording method, an image having a more stable density can be formed.

According to the thermal recording method of the present invention, a laser beam from a heating beam generating means is irradiated with a laser beam from a heating beam generating means by modulating the recording material with a density corresponding to the applied thermal energy in accordance with the recording information. In this method, after performing invisible recording, the entire surface of the recording material is uniformly heated again at a temperature lower than the color development temperature, whereby the color development reaction is promoted, and an image or the like having a stable density can be obtained. (Hereinafter, heating after recording such as visible or invisible by the laser beam is referred to as post-heat.) The post-heat temperature is set between 40 and 275 ° C. according to the coloring properties of the recording material. The preheating time is desirably set to 30 seconds or less from the viewpoint of throughput. More preferably, the eutectic point of the color-forming component, or, when the color-forming component is microencapsulated, the glass transition temperature of the microcapsule wall material, etc.
The temperature is preferably set to about 150 ° C. For example, when a material having a color development temperature of 120 ° C. is used, it is preferable to heat at about 100 to 110 ° C. for about 0.5 to 25 seconds.

Prior to recording (imagewise irradiation) such as visible or invisible with the laser beam, the entire surface of the recording material is uniformly preheated at a temperature lower than the coloring temperature. If it is carried out, the dynamic range of the laser beam at the time of recording can be sufficiently ensured, whereby a high gradation image or the like can be easily obtained. (Hereinafter, preheating prior to recording such as visible or invisible by the laser beam is referred to as preheating.) The preheating condition is the same as the preheating temperature (40 to 275 ° C., preferably 70 ° C.).
To 150 ° C.) or less, and the heating time is likewise 30 seconds or less, preferably 10 seconds or less. Specifically, for example, when a material having a coloring temperature of 120 ° C. is used, about 0.05 to 2.5 under a temperature condition of 100 to 110 ° C.
Heating is preferably performed for about seconds, and more preferable heating time is about 0.1 second. Even if the preheating temperature does not reach the coloring temperature, long-time heating exceeding 10 seconds affects the coloring component, which is not preferable. Also,
Preheating, when performing post-heating following visible or invisible recording by a laser beam, the heating temperature of the post-heating is preferably equal to or lower than the temperature of the pre-heating, and the heating time of the post-heating may be longer than the pre-heating. preferable.

Specifically, the effect of preheating is as follows. For example, when a material having a coloring temperature of 120 ° C. and preheating at a temperature of 110 ° C. for 0.1 second are performed, the coloring by the laser beam is reduced by 40 mJ /. relative to the recording material requires energy mm ^2, it is possible to perform recording by the laser beam energy of 4 mJ / mm ² was confirmed.

In order to perform recording by adding such pre-heating and post-heating processing, it is preferable to use a recording apparatus having a heating means adapted to the above-described method. Hereinafter, a recording method to which preheating and postheating are added will be described with time using examples.

The recording material is preheated while being scanned and conveyed while being held between the heat rollers. The preheating temperature just before coloring by heating of the heat roller is preheated to (hereinafter, referred to as the temperature T _1).

Next, the laser diode outputs a laser beam modulated in accordance with the gradation of the image recorded on the recording material, and a predetermined photothermal energy is applied to the recording layer of the recording material by the laser beam. , A gradation image is recorded.

Next, the recording material on which a gradation image is recorded
Material is transported while being held between heat rollers.
Then, it is heated again and subjected to a post-heat treatment. You
That is, the recording material has a temperature T just before coloring.₁(Preheat
(Same as temperature). In this case, the laser beam
The recording material having a development nucleus again has a temperature T ₁
Heating to promote the color development reaction,
The degree rises to the desired value.

As described above, after the image is recorded by the laser beam, the post-heating treatment is again performed to heat the recording material to a temperature immediately before color development, whereby the color development reaction is completed, and there is no change with time thereafter. An image having a stable density can be obtained for a long period of time.

Further, an ultraviolet-curing material was selected as a binder component contained in the recording layer of the recording material or a wall material of the microcapsules, and an ultraviolet lamp was provided downstream of the post-heat heating section. After performing the post-heat treatment, the image density can be more reliably stabilized by performing ultraviolet fixing. That is, after the formation of the visible image necessary for color development by the laser beam is completed, the recording material is heated by the post-heat heating unit, and further, the recording material is irradiated with ultraviolet rays from an ultraviolet lamp to form the recording layer containing the coloring component. Is hardened, the subsequent reaction is suppressed, and an image having a long-term stable density can be obtained without a change over time.

As a heating means for these pre-heating and post-heating treatments, it is common to use a pair of heat rollers as described above. However, when a plurality of heat rollers are arranged in the scanning direction, The heating temperature after recording of the recording material can be set stably and with high accuracy. That is, by using a plurality of heat rollers, it is possible to prevent uneven heating temperature when a heat roller having a small heat capacity is used. Further, by providing a heating light source at the subsequent stage of the heat roller, and further heating the recording material by the heating light source after heating by the heat roller, the heating temperature unevenness can be prevented. Further, the same effect can be obtained by performing radiant heating with a heating light source prior to heating with a heat roller. In addition, the case of the residual heat means can be similarly configured.

As the heating means, in addition to a heat roller, radiant heating by a heating light source, heating by a heater through a thin belt, heating to absorb infrared rays radiated from an infrared heater, hot air heating by a hot air heater, and the like are used. Can be applied. Control of the heating time by these heating means,
This can be done by adjusting the size of the heating means and the running speed of the recording material.

The recording material of the present invention preferably contains a compound having an intramolecularly active halogen group in the recording layer, as described above. A recording material comprising a recording layer containing no silver halide is irradiated with a laser beam modulated in accordance with recording information.
After the step, a step of uniformly exposing the entire surface of the recording material irradiated imagewise with a light source of ultraviolet to visible light is provided, and thereafter, the entire surface of the recording material that has been entirely exposed is lower than the color development temperature of the recording material. It is preferable to perform the third step of uniformly heating at the predetermined temperature from the viewpoint of improving sensitivity. Here, the compound having an intramolecularly active halogen group contained in the recording layer forms a halogen radical at a portion irradiated with a laser beam imagewise, and the radical reacts with an organic silver salt to form a predetermined silver nucleus. In this case, silver halide is formed. Therefore, by performing a process of uniformly exposing with this new ultraviolet to visible light source, the formed silver halide develops a color and a higher density image can be formed. This recording material includes a process of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than the color development temperature, as in the above-described respective recording methods that do not include the entire surface exposure process. It is something that can be done.

The recording material of the present invention can be applied not only to the recording method specific to the present invention but also to a known recording method. For example, for the purpose of improving heat sensitivity, contrast, and image quality, irradiation with a laser beam described in a publication of a silver halide light-sensitive and heat-sensitive recording material proposed by 3M in International Application WO95 / 31754 has a predetermined overlap. Can be applied to the recording method of performing

That is, in the laser beam irradiation for forming a latent image, (1) a beam is supplied from a radiation light source which forms a spot having at least one of a height and a length of 600 μm or less at a target position; (3) supplying a recording material sensitive to the light source to the target position, and (3) first applying the recording material according to an image distribution by a radiation light source that forms a spot in which at least one of a length or a width is 250 μm or less. Irradiating, (4) a technique of irradiating the recording material according to an image distribution such that at least some spots from the second irradiating beam overlap the first irradiating spot of the recording material, A method of forming a latent image on the material by exposing the material to (1) exposing the material to a radiation light source capable of sensitizing the material, and (2) exposing the material to a size of 600 μm or less in one direction. Irradiating at least 10% of the individual sub-regions of the material with another sub-region in the sense of at least 10% of the total energy of the at least one sub-region, It is the basis.

Further, a recording material proposed by Canon Inc. in JP-A-60-195568 can also be applied. That is, by tilting the angle at which the irradiation laser beam is incident on the recording material surface, the reflection pitch at which the incident beam interfacially reflects the thin layer of the recording material is made larger than the beam spot diameter of the beam, By applying a technique characterized by preventing light interference occurring in the recording material, a higher quality image can be obtained.

[0179]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. Unless otherwise specified in the text, "%" is "% by weight"
And “parts” means “parts by weight”.

(Example 1) Preparation of silver behenate 25.59 g of behenic acid was added to 480 g of water, heated to 90 ° C, added with an aqueous solution in which 3.0 g of NaOH was dissolved in 45 g of water, and stirred well. Then, it cooled to 50 degreeC.

Next, Ag was added to 75 g of water.
After an aqueous solution to which 12.9 g of NO ₃ had been added was added dropwise over 5 minutes, stirring was continued for 30 minutes to cause a reaction.

The obtained reaction solution was filtered through a filter cloth, and water 800
After adding ml, stirring and washing, the mixture was filtered again. After such a washing operation was repeated three times, the obtained solid content was reduced to 5%.
It was dried for 3 days by a blow dryer at 0 ° C. to obtain a dried solid of silver behenate.

Preparation of co-dispersion of silver behenate / infrared absorbing dye
It was weighed 14g from manufacturing prep silver behenate dry solids, this carboxy benzotriazole methyl ester 1.0
6 g, 0.282 g of an infrared absorbing dye represented by the following formula (hereinafter referred to as an infrared dye as appropriate), and a 15% aqueous solution of polyvinyl alcohol (trade name: PVA205; Kuraray Co., Ltd.)
35g) and 68 g of ion-exchanged water were added thereto and dispersed for 3 hours with a paint shaker to obtain a silver behenate / infrared dye co-dispersion liquid having an average particle diameter of 0.6 µm.

[0184]

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Preparation of Developer Dispersion Solution To 53 g of a 15% aqueous polyvinyl alcohol solution (PVA205, hereinafter the same as described above), 24 g of a developer represented by the following formula and 103 g of ion-exchanged water were added, and dispersed with a paint shaker for 3 hours to obtain an average particle size. A 0.6 μm developer dispersion was prepared.

[0186]

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Preparation of 4-Methylphthalic Acid Dispersion 15% aqueous solution of polyvinyl alcohol (PVA205) 3
To 3 g, 20 g of 4-methylphthalic acid and 67 of ion-exchanged water
g, and dispersed for 3 hours with a paint shaker to prepare a dispersion having an average particle size of 0.6 μm.

Preparation of Coating Solution for Recording Layer 21.7 g of the silver behenate / infrared dye co-dispersion, 3.8 g of the developer dispersion, 0.28 g of the 4-methylphthalic acid dispersion, 15% polyvinyl alcohol (PVA20)
5) 3.2 g of solution, 50% aqueous solution of phthalazine 0.34
g was added to prepare a recording layer coating solution.

Preparation of Coating Solution for Protective Layer 32 g of water and 10% of carboxy-modified polyvinyl alcohol (trade name: PVA-KL-318, manufactured by Kuraray Co., Ltd.)
32 g of an aqueous solution of an epoxy-modified polyamide (trade name:
FL-71, manufactured by Toho Chemical Co., Ltd.) and 8 g of a 30% dispersion, mixed with polyoxyethylene (surfactant) 2
5 g of a 20% aqueous solution and 4 g of a dispersion of 20% zinc stearate (trade name: Hydrin Z, manufactured by Chukyo Yushi Co., Ltd.) were added to obtain a coating solution for a protective layer.

Preparation of Recording Material for Infrared Laser On a transparent polyethylene terephthalate support (130 μm / thickness) provided with an undercoat layer, the coating liquid for the recording layer was dried with a wire bar to a dry film thickness of 10 g / m ^2. And dried at 50 ° C. for 20 minutes.

Next, a coating liquid for a protective layer was further applied on this coating film so that the solid content was 2.0 g / m ^2, and dried to obtain a recording material for infrared laser.

Example 2 Preparation of Capsule Solution Encapsulating Silver Behenate 27 g of the prepared silver behenate dry solid was weighed, and 0.54 g of the infrared dye used in Example 1 and polyvinyl butyral were used. 10 g and 110 g of isoamyl acetate were added, and the mixture was dispersed with a paint shaker for 3 hours, and further dispersed with a motor mill to obtain a silver behenate dispersion having an average particle diameter of 0.4 μm.

In 10 g of the obtained dispersion, Takenate D-110N (trade name, manufactured by Takeda Pharmaceutical Co., Ltd .: isocyanate compound having the structure of the above formula (a)) as a capsule wall material.
What added 5 g was used as the oil phase component. This is 10%
It was added to a solution (aqueous phase) obtained by mixing 16 g of an aqueous solution of polyvinyl alcohol (trade name: PVA217E, manufactured by Kuraray Co., Ltd.) and 40 g of water, and further treated at 8,000 rpm using a homogenizer (Ace Homogenizer manufactured by Nippon Seiki) at 10 rpm. It was finely emulsified for minutes.

The obtained fine emulsified dispersion was heated to 40 ° C. while stirring, and kept for 3 hours to carry out an encapsulation reaction. The obtained liquid is a microcapsule liquid containing silver behenate and having an average particle size of 0.8 μm.

Preparation of Coating Solution 93 g of the silver behenate-encapsulated capsule, 3.8 g of the same developing solution as used in Example 1, 0.28 g of the 4-methylphthalic acid dispersion, 5% carboxybenzotriazole methyl ester in methanol 4 g and 0.34 g of a 50% aqueous solution of phthalazine were added to prepare a coating solution.

Preparation of Thermosensitive Recording Material for Infrared Laser In the same manner as in Example 1, the coating solution was dried in a thickness of 19 g.
/ M ² , followed by drying, and then a protective layer is applied on the coating so as to have a dry film thickness of 2.0 g / m ² and dried. Obtained.

Example 3 Preparation of Developer Microcapsule Solution 5 g of the same developer as in Example 1, 15 g of ethyl acetate, 5 g of diisopropylnaphthalene, Takenate D-110N
(Takeda Pharmaceutical Co., Ltd.) 7 g was dissolved, and this was added to a mixed solution of 60 g of polyvinyl alcohol 8% aqueous solution (PVA217E) and 20 g of water. Solidification and microencapsulation were performed in the same manner as in Example 2 to obtain a developer. The average particle size included is 0.
A 5 μm microcapsule solution was obtained.

Preparation of Recording Material for Infrared Laser The procedure of Example 1 was repeated, except that instead of adding 3.8 g of the developer dispersion, 11.3 g of the developer microcapsule liquid was added to obtain a dry film thickness of 13 g / m ^2. A recording material for infrared laser was obtained in the same manner as in Example 1.

Example 4 A recording material for an infrared laser was prepared in exactly the same manner as in Example 1 except that the compound represented by the following structural formula was used as the infrared dye.

[0200]

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Example 5 A recording material for infrared laser was prepared in exactly the same manner as in Example 1 except that the compound represented by the following structural formula was used as the infrared dye.

[0202]

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Example 6 A recording material for infrared laser was prepared in exactly the same manner as in Example 1 except that the compound represented by the following structural formula was used as the infrared dye.

[0204]

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(Example 7) Synthesis of aqueous polymer latex 2 parts of sodium di (2-ethylhexyl) sulfosuccinate was dissolved in 500 parts of distilled water, and the mixture was dissolved at 85 ° C under a nitrogen atmosphere.
And a solution prepared by dissolving 0.85 part of potassium persulfate in 50 parts of distilled water was added. While stirring at 350 rpm, 140 parts of benzyl methacrylate was added dropwise over 1 hour. After cooling, this was neutralized with a 0.25N aqueous sodium hydroxide solution to obtain an aqueous polymer latex. The solid content of this latex was 18.7%, and the particle size was 0.09 μm.

Preparation of developer-filled polymer latex A In 160 parts of acetone, 4.4 parts of the developer used in Example 1 was dissolved, and 90 parts of the aqueous polymer latex synthesized as described above was added with stirring. Stirred for minutes. After the acetone was distilled off under reduced pressure, the precipitate was separated by filtration to obtain a developer-filled aqueous polymer latex. The solids content of this latex is 23
%, And the ratio of the developer to the solid content was 19.4%.

Preparation of Developer- Loaded Polymer Latex B 1.6 g of sodium lauryl sulfate was dissolved in 400 g of distilled water, and a solution prepared by dissolving 12.5 g of the developer used in Example 1 in 100 g of ethyl acetate was added. The emulsion was obtained by sonication. The polybenzyl methacrylate latex (solid content: 18.7) obtained in the above Synthesis Example was added to 50 g of the above emulsion.
%) And stirred at room temperature for 3 hours. Further, ethyl acetate was removed under reduced pressure to obtain a developer-filled polymer latex. The yield was 56 g, the solid content concentration was 4.24%, and the developer concentration was 2.23%.

Preparation of Recording Material for Infrared Laser In Example 1, instead of adding 3.8 g of the developer dispersion, 11.3 g of the polymer latex A filled with the developer was added so that the dry film thickness became 13 g / m ^2. A recording material was obtained in the same manner as in Example 1 except that the coating was performed, and this was designated as Sample 7 (A). Similarly, instead of adding 3.8 g of the developer dispersion, 22.6 g of the polymer latex B filled with the developer was added.
Sample 7 (B) was adjusted to have a dry film thickness of 13 g / m ² .

[Image Recording and Evaluation] As described above, Examples 1 to 7
Was irradiated imagewise from the recording layer side with a semiconductor infrared laser beam (GaAs junction laser) having a wavelength of 780 nm. Thereafter, the mixture was heated uniformly at 100 ° C. for 15 seconds, and its color transmission density was measured with a Macbeth density system. The output of the laser was adjusted to have an energy of 1.0 mJ / mm ^{2 on} the surface of the recording layer. No image was observed in any of the samples after the laser irradiation and before the uniform heating.

Further, an accelerated deterioration test in which the image was stored at 40 ° C. × 90% RH for 3 days was performed, and a change in density of the image before and after the storage was examined.

The results are shown in Table 1 below. (Example 8) Preparation of recording material for infrared laser In Example 1, 10% methanol of 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine was added to the coating liquid for the recording layer. A recording material for infrared laser was prepared in the same manner as in Example 1 except that 0.4 g of the solution was added.

[Recording and Evaluation of Image] The sample obtained in Example 8 was imagewise irradiated with a semiconductor infrared laser beam (GaAs junction laser) having a wavelength of 780 nm from the recording layer side. The output of the laser is 1.0 mJ / mm on the surface of the recording layer.
^It was prepared to have an energy of ² . Next, "Dai Nippon Screen Co., Ltd."
647-FA, GA ", the whole surface was irradiated with 500 counts of UV-visible light, and then uniformly heated at 100 ° C. for 15 seconds, and its color transmission density was measured with a Macbeth density system.

Further, an accelerated deterioration test in which the image was stored at 40 ° C. × 90% RH for 3 days was performed, and the change in density of the image before and after the storage was examined.

The results are shown in Table 1 below.

[0215]

[Table 1]

In the recording materials of the present invention, an image appears due to post-heating after laser exposure, and the laser sensitivity is expressed under given laser irradiation conditions by an organic borate salt. It was also found that the sample to which the infrared absorbing dye was added had sufficient color density of the recorded image.

Further, the change in the background density before and after the accelerated deterioration test was at a level causing no practical problem. Furthermore, among Examples 2, 3 and 7 (A) and 7 (B) using microcapsules and a core-shell type latex dispersion, Examples 2 and 3 in which silver behenate and an infrared absorbing dye were encapsulated in microcapsules were used. It was confirmed that Example 3 in which the developer was encapsulated in microcapsules was particularly excellent in storage stability. Example 8 in which the recording layer contained a compound having an intramolecularly active halogen group and the entire surface was exposed was compared with Example 1 having the same configuration except that the recording layer did not contain a compound having an intramolecularly active halogen group. As a result, it was found that the image density after recording was significantly increased.

[0218]

The recording material of the present invention has a high laser beam absorption efficiency, has less coloring of the background, and enables high-quality recording. Further, the recording method of the present invention using the recording material is effective. Can stabilize the density of an image after recording, and can secure a sufficient dynamic range of a laser beam for recording an image and the like, and obtain a high-gradation and high-precision image and the like. This has the effect.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomomasa Usami 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Inside Fuji Photo Film Co., Ltd.

Claims (17)

[Claims] 1. A recording material comprising a support having thereon a recording layer containing an organic silver salt, an organic silver salt developer and a binder, wherein the recording layer contains an organic borate salt of a cationic dye. Recording material characterized by the above-mentioned. 2. A recording material comprising a support and a recording layer containing an organic silver salt, an organic silver salt developer and a binder and not containing silver halide, wherein a cationic dye organic borate salt is used. Recording material characterized by containing. 3. The organic borate salt of a cationic dye is as follows:
Characterized by being a compound represented by the general formula (I)
Recording material. Embedded image(Where D⁺Represents a cationic dye, and R¹, R^Two, R^ThreeYou
And R^FourIs a halogen atom, a substituted or unsubstituted
An alkyl group, a substituted or unsubstituted aryl group,
Is an unsubstituted aralkyl group, a substituted or unsubstituted alkali
A substituted or unsubstituted alkenyl group, a substituted or unsubstituted
Unsubstituted alkynyl group, substituted or unsubstituted alicycle
Rick group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted
Represents a substituted allyl group or a substituted or unsubstituted silyl group.
Where R¹, R^Two, R^ThreeAnd R ^FourAre the same as each other
These two or more groups may be bonded to each other to form a ring.
May be formed. ) 4. The cationic dye is a cationic methine dye, a cationic polymethine dye, a cationic triarylmethane dye, a cationic indoline dye, a cationic azine dye, a cationic xanthene dye, a cationic oxazine dye, a cationic acridine 3. The recording material according to claim 2, wherein the recording material is a dye selected from the group consisting of a dye and a cationic styryl dye. 5. The dye according to claim 3, wherein the cationic dye is a dye selected from the group consisting of a cationic cyanine dye, a cationic hemicyanine dye, a cationic rhodamine dye, and a cationic azamethine dye. Recording material. 6. The recording material according to claim 1, wherein the organic silver salt is contained in a solid dispersion state. 7. The recording material according to claim 1, wherein at least one of the organic silver salt and the organic silver salt developer is microencapsulated. 8. The recording material according to claim 1, wherein an organic silver salt and an organic borate salt of a cationic dye are contained in the thermoresponsive microcapsules. 9. A recording layer comprising an organic silver salt and an organic borate salt of a cationic dye and not containing an organic silver salt developer, an organic silver salt developer and an organic silver salt developer. 2. The recording material according to claim 1, wherein a layer containing no silver salt and an organic borate salt of a cationic dye is laminated. 10. The recording material according to claim 1, wherein a developer of an organic silver salt is contained in the polymer latex. 11. The recording material according to claim 1, wherein the recording layer contains a development accelerator of an organic silver salt. 12. A compound having an intramolecularly active halogen group in a recording layer, a thiol compound, a thioketone compound, an organic peroxide, a lophine dimer compound, an iodonium salt, a sulfonium salt, an azinium salt, a naphthoquinone diazide compound, and an iminoquinone diazide compound. The recording material according to claim 1, wherein the recording material contains at least one compound selected from the group consisting of: 13. A recording layer containing at least an organic silver salt, a developer of an organic silver salt, a binder and an organic borate salt of a cationic dye represented by the formula (I) is provided on the support. A first step of irradiating the recording material provided with the laser beam modulated in accordance with the recording information to the recording material provided on the surface of the recording material; A second step of uniformly heating at a temperature; and a recording method. 14. A recording layer comprising at least an organic silver salt, a developer of an organic silver salt, a binder, and an organic borate salt of a cationic dye represented by formula (I) is provided on a support. A first step of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than the coloring temperature; and a second step of irradiating the preheated recording material with a laser beam modulated according to recording information. And a recording method comprising: 15. A recording layer containing at least an organic silver salt, a developer of an organic silver salt, a binder, and an organic borate salt of a cationic dye represented by formula (I) is provided on a support. A first step of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than the coloring temperature; and a second step of irradiating the preheated recording material with a laser beam modulated according to recording information. And a third step of uniformly heating the entire surface of the recording material irradiated imagewise at a predetermined temperature lower than the coloring temperature of the recording material. 16. A compound having at least an organic silver salt, a developer of an organic silver salt, a binder, an organic borate salt of a cationic dye represented by formula (I) and an intramolecularly active halogen group on a support. A first step of irradiating a recording material comprising a recording layer containing no silver halide with a laser beam modulated in accordance with recording information; and the recording material irradiated image-wise A second step of uniformly exposing the entire surface of the recording material with a light source of ultraviolet to visible light, and a third step of uniformly heating the entire surface of the recording material exposed to the entire surface at a predetermined temperature lower than the coloring temperature of the recording material. And a recording method comprising: 17. The recording method according to claim 16, further comprising, before the first step, a step of uniformly preheating the entire surface of the recording material to a predetermined temperature lower than a coloring temperature.