JPH02190386A - Multicolor thermal recording material - Google Patents

Abstract

PURPOSE:To obtain the title material which has favorable color separation properties and excellent hue reproduction properties by using a combination of a diazo compound with a coupler for at least one thermal color forming layer, and using a combination of an electron donative dye precursor with a color developer as a color forming system for at least one other layer. CONSTITUTION:A combination of a diazo compound with a coupler is used as a color forming system for at least one thermal color forming layer in a thermal recording layer, and a combination of an electron-donative dye precursor with a color developer is used as a color forming system for at least one other layer. A decolorizing system comprising a combination of at least one compound selected from organoboron compound anionic salts of an organic cationic coloring matter compound of the formula (wherein D<+> is a cationic coloring matter, each of R1 to R4, which may be the same or different, is a group selected from alkyl, aryl, aralkyl, alkaryl, alkenyl, alkynyl, alicyclic groups, heterocyclic groups, allyl and derivatives thereof, and two or more of R1, R2, R3 and R4 may be linked to each other to form a cyclic structure) with at least one compound selected from compounds capable of breaking at least one of carbon-boron bonds is used as an image forming system for at least one other layer in the thermal recording layer. At least the organoboron compound anionic salt of the organic cationic coloring matter compound and the compound capable of breaking at least one carbon- boron bond are separated from each other by a microcapsule wall.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multicolor recording material, and more particularly to a multicolor thermosensitive recording material capable of thermal and/or photosensitive recording.

(Prior Art) As the most common method for obtaining multicolor images, silver/salt photography has been widely put into practical use because of its high sensitivity, high image quality, and rich gradation reproducibility. However, silver halide photography has the drawback that the process is complicated because it processes the image with a developer after exposure and then converts the remaining silver halide into water-soluble silver complex salts or light-stable silver salts. have.

As a method to improve these drawbacks,
No. 764, etc. describe dry silver salt photographic materials, British Patent No. 249530, U.S. Patent No. 2゜020.775,
Same No. 2,004,625, Same No. 2,217,544, Same No. 2,255,463, Same No. 2,699,394
There are descriptions of dye diffusion transferable photographic materials in US Pat.

On the other hand, recording methods such as electrophotography, thermal transfer, and inkjet methods are used as recording materials that do not use silver salts, but the devices are equipped with multicolor recording mechanisms, such as electrophotographic methods, thermal transfer methods, and inkjet methods. It has disadvantages such as lack of chain properties and the time it takes to replace consumables.

As a non-silver salt recording material that has a multicolor recording mechanism, recording materials that combine pressure-sensitive, heat-sensitive, photosensitive, etc. color development methods are disclosed in JP-A-63-134282 and JP-A-63-134282.
No. 3-154386, No. 63-172680, No. 63
-172681, 63-189282, 63-
It is described in No. 218392 and No. 63-45084.

Furthermore, examples of conventional methods using heat-sensitive recording methods include Japanese Patent Publications Nos. 51-19989 and 52-
No. 11231, JP-A-54-88135, JP-A No. 55-1
As described in No. 33991 and No. 55-133992, there is a method in which a plurality of color forming units are simply added one after another as the imprint heating energy increases, and the colors are mixed and the hue changes while becoming muddy. Other methods include, for example,
No. 7868, No. 51-5791, No. 57-14318
No. 57-14319 and JP-A No. 55161688, it is said that when a color forming unit with a higher thermal response temperature develops color, a decoloring agent acts at the same time to decolor the color forming unit that develops color at a low temperature. There are some that incorporate a color erasing mechanism.

However, all of these methods not only have a small number of color hues that can be realized, but also have turbidity due to bleeding and color mixing, so it is difficult to say that they have sufficient functionality as a color hard copy. In particular, as a color hard copy, the fact that the number of color hues that can be developed is small in principle is a fatal drawback. The following points can be cited as one of the major reasons why this drawback could not be overcome in the past. For example, if you want to increase the number of color hues, you can simply increase the number of fractions of applied heating energy and widen the energy difference between them, thereby creating the corresponding heat-sensitive coloring layers on the same support. It would be possible to design a heat-sensitive recording material with multiple heat-sensitive recording materials, but in reality, if the applied heating energy is extended to a lower range than before, problems will arise in terms of storage stability (so-called fog) of the recording material itself. On the other hand, when the applied heating energy is extended to a high range, new serious problems arise in terms of scorching of the image, poor print running properties due to fusion (for example, sticking), and shortening of the life of the thermal head.

Therefore, the maximum number of fractions of conventional applied heating energy that can be allowed is actually about 2 fractions in order to satisfy the color separation property.

On the other hand, as a support for heat-sensitive recording materials, an opaque support such as paper or synthetic paper is usually used. This is due to the purpose of simply reading a colored image as a reflected image from one side.

Furthermore, the invention of providing two or more color images by providing heat-sensitive recording layers with different color hues on both sides of a transparent support is disclosed in JP-A-49-114431 and JP-A-50-36.
No. 40 and Japanese Patent Application Laid-Open No. 60-4092. However, since the heat-sensitive color forming layer of these is simply a dispersion of color forming components and color developing components in a solid state,
Due to the scattering of light, the coloring layer itself essentially becomes an opaque layer, making it impossible to obtain the desired multicolor image with clear color separation. There is also a description of dissolving each component and applying it to the same layer in order to improve the transparency of the heat-sensitive coloring layer, but in this case, the coloring of each component easily occurs before printing, resulting in so-called fog.

Therefore, in any case, the above-mentioned known techniques have a small number of possible color divisions, and are essentially unsatisfactory as multicolor recording materials.

The present inventors have already proposed a multicolor heat-sensitive recording material having a substantially transparent heat-sensitive layer capable of solving such drawbacks (for example, JP-A-63-45084, JP-A-63-45084;
-172680, 63-172681, 63-
No. 189282, No. 63-189283, No. 63-
No. 193878, No. 63-218392, No. 63-2
No. 31982).

In particular, one of the diazo compound or the coupler is contained in microcapsules, the other is dissolved in an organic solvent that is sparingly soluble or insoluble in water, and then emulsified and dispersed to prepare an emulsified dispersion, and then the two are mixed. The heat-sensitive recording material, which has a heat-sensitive layer made transparent by applying and drying a coating solution, is excellent in that it can be optically fixed (Japanese Patent Application No. 155212-1982), and it can produce multicolor images. This could greatly contribute to the development of

However, there is a limit to the hue that can be reproduced by photofixable diazo compounds, and it has been difficult to achieve satisfactory multicolor image quality.

(Problem to be Solved by the Invention) As a result of intensive studies to solve the conventional drawbacks, the present inventors have found a combination of a diazo compound and a coupler that can be photofixed as a thermochromic system in a heat-sensitive layer, and an electron-donating property. In addition to using a combination of a dye precursor and a color developer, at least one other layer of the heat-sensitive layer is photobleached using at least one compound selected from organic boron compound anion salts of organic cationic dye compounds. The present inventors have discovered that by using the color erasing system, it is possible to reproduce high-quality multicolor images with excellent hue reproducibility of three or more colors.

Therefore, an object of the present invention is to provide a multicolor thermosensitive recording material that has good color separation and excellent hue reproducibility.

(Means for Solving the Problems) The above-mentioned object of the present invention is to provide a multicolor heat-sensitive recording material comprising at least a support and three or more heat-sensitive layers each capable of recording images of different hues. As a coloring component of the coloring layer, a combination of a diazo compound and a coupler is used as a coloring system for at least one layer, and a combination of an electron-donating dye precursor and a color developer is used as a coloring system for at least one other layer, and At least one compound selected from organic boron compound anion salts of organic cationic dye compounds represented by the following general formula (I) and one carbon-boron bond for at least one other layer of the layers. A multicolor heat-sensitive recording material using as an image forming system a color erasing system consisting of a combination with at least one compound selected from the above destructible compounds, the organic boron compound of at least the organic cationic dye compound. This was achieved by a multicolor thermosensitive recording material characterized by using an anion salt and a compound capable of breaking one or more carbon-boron bonds, separated by the walls of microcapsules.

General formula (I) Here, Do is a cationic dye, R1-R4 may be the same or different (alkyl group, aryl group, aralkyl group, alkaryl group, alkenyl group, alkynyl group, alicyclic group) , a heterocyclic group, an allyl group, and a derivative thereof, and R, , R, , R, and R4 may be a cyclic structure in which two or more of these groups are bonded.

Next, an image forming method for a typical example of the heat-sensitive recording material of the present invention will be explained with reference to the drawings.

Figure 1 shows a heat-sensitive recording material in which a cyan coloring heat-sensitive layer, a magenta coloring heat-sensitive layer and a yellow coloring heat-sensitive layer are sequentially laminated on a support. A case will be described in which a combination of a diazo compound and a coupler is used in the yellow thermosensitive layer.

In order to record three-color images on the above heat-sensitive recording material,
First, thermal printing is performed using low thermal energy to form a yellow image on the top layer, and then the entire surface is irradiated with light in the decomposition wavelength range of the diazo compound to optically fix the yellow image. Then, the magenta color is imagewise fixed on the second color magenta colored layer, and then the entire surface is irradiated with light in the absorption coloring region of the organic cationic dye to erase the color of the non-image area and record a magenta image. Since the light used in this case has a longer wavelength than yellow, the upper yellow image does not particularly interfere.

Finally, thermal printing is performed using higher energy to form a cyan image on the bottom layer. In this case, the upper two layers have already been optically fixed and are not affected at all even if heated again, so cyan, magenta and yellow images are formed independently.

Therefore, by making at least the upper two layers substantially transparent heat-sensitive layers, it is possible to produce cyan, magenta, yellow, cyan, magenta (blue), and magenta + yellow (red), which have been considered difficult in conventional heat-sensitive recording. , Cyan Yellow (Green), Cyan + Magenta + Yellow (
This means that a total of seven basic colors (black) can be realized with good color separation (see Figure 2).

When an opaque support is used as the support, the lowermost heat-sensitive layer may be transparent or opaque.

If a transparent support is used as a support and all heat-sensitive layers are substantially transparent heat-sensitive layers, the above full-color image can be converted into an OH
P (overhead projector).

In this case, optical fixation during image recording can be performed not only from the top surface but also from the support side, so the heat-sensitive layer uses a diazo compound and the heat-sensitive layer uses an organic boron compound anion salt of an organic cationic dye. The stacking order is arbitrary.

Furthermore, if OHP projection is not intended, the uppermost heat-sensitive layer may be made opaque.

In this case, the multicolor image will be viewed as a reflected image from the transparent support side.

Next, the materials used in the multicolor heat-sensitive recording material of the present invention will be described in detail.

The diazo compound used in the present invention refers to a photodegradable diazo compound that decomposes and loses reactivity when exposed to light of a specific wavelength before reaction, and mainly refers to aromatic diazo compounds. refers to aromatic diazonium salts, diazosulfonate compounds, diazoamino compounds, etc., and will be explained below mainly by citing diazonium salts as examples.

It is generally said that the photodecomposition wavelength of a diazonium salt is its maximum absorption wavelength. Also, the maximum absorption wavelength of diazonium salts ranges from around 200nm to 700nm, depending on its chemical structure.
It is known that the photodecomposition and chemical structure of photosensitive diazonium salts changes up to about
65)).

That is, when a diazonium salt is used in a heat-sensitive recording material, a recorded image can be fixed by irradiating light of a specific wavelength depending on the chemical structure of the material after thermal recording. Furthermore, by changing the chemical structure, the hue of the dye after the reaction can be changed even when the same coupler is used in the coupling reaction.

A diazonium salt is a compound represented by the general formula ArN, "X-" (wherein A represents a substituted or unsubstituted aromatic moiety, N8 represents a diazonium group, and X- represents an acid Hail anion, ).

Among these, compounds having a photolysis wavelength around 400 nm include 4-diazo-1-dimethylaminobenzene, 4-diazo-1-diethylaminobenzene, 4-diazo-1-dipropylaminobenzene, and 4-diazo-1-dimethylaminobenzene. 1-
Methylbenzylaminobenzene, 4-diazo-1-dibenzylaminobenzene, 4-diazo-1-ethylhydroxyethylaminobenzene, 4-diazo-1-diethylamino-3-methoxybenzene, 4-diazo-1-dimethylamino- 2-methylbenzene, 4-diazo-1-benzoylamino-2,5-jethoxybenzene, 4-diazo-1-morpholinobenzene, 4-diazo-1-morpholino-2,5-jethoxybenzene, 4-diazo -1
-Morpholino-2゜5-dibutoxybenzene, 4-diazo-1-anilinobenzene, 4-diazo-1-1-ruylmerkabuto 2,5-jethoxybenzene, 4-diazo-1,4-methoxy Examples include benzoylamino-2,5-jethoxybenzene. 300-37
Examples of compounds having a photolysis wavelength of 0 nm include 1-diazo-4-(N,N-dioctylcarbamoyl)benzene, l-diazo-2-octadecyloxybenzene, and l-diazo-2-octadecyloxybenzene.
Diazo-4-(4-tert-octylphenoxy)benzene, 1-diazo-4-(2,4-di-tert-amylphenoxy)benzene, l-diazo-2-(4-t
ert-octylphenoxy)benzene, 1-diazo-
5-chloro-2-(4-tert-octylphenoxy)benzene, 1-diazo-2,5-bis-octadecyloxybenzene, l-diazo-2,4- and su-octadecyloxybenzene, l-diazo-4- (N-octylteraroylamino)benzene etc.0
The photolysis wavelength of the aromatic diazonium compounds typified by the examples listed above can be varied widely by arbitrarily changing the substituents.

A specific example of an acid anion is CRF! 1%41COO
- (n represents 3 to 9), c, F z**+SQ
, -(m represents 2 to 8), (CL Ft+-+So
! )t CH- (j! represents 1 to 18), CH.

Specific examples of the diazo compound (diazonium salt) include the following examples.

N-CH.

(JL; Hs (CH.

The diazosulfonate compound that can be used in the present invention is a compound represented by the general formula 0, where R+ is an alkali metal or an ammonium compound, R1, Rs, Rs, and Rh.
is hydrogen, halogen, alkyl group, or alkoxy group, and R4 is hydrogen, halogen, alkyl group, amino group, benzoylamido group, morpholino group, trimercapto group, or pyrrolidino group.

A large number of such diazosulfonates are known and can be obtained by treating each diazonium salt with a sulfite.

Preferred compounds among these compounds include 2-methoxy, 2-phenoxy, 2-methoxy-4-phenoxy, 2,4-dimethoxy, 2-methyl-4-methoxy,
Benzenediazosulfonate having a substituent such as 2,4-dimethyl, 2,4゜6-trimethyl, 4-phenyl, 4-phenoxy, 4-acetamide, or 4-(N-
ethyl, N-benzylamino), 4-(N,N-dimethylamino), 4-(N,N-diethylamino), 4-(
N,N-diethylamino)-3-chlor, 4-pyrogeno-3-chlor, 4-morpholino-2-methoxy, 4-
It is a benzenediazosulfonic acid salt having a substituent such as (4°-methoxybenzoylamino)-2,5-dibutoxy and 4-(4°-trimercab))-2,5-dimethoxy. When using these diazosulfonate compounds,
It is desirable to perform light irradiation to activate the diazosulfonate before printing.

Further, other diazo compounds that can be used in the present invention include diazoamino compounds. Diazoamino compounds include compounds in which a diazo group is coupled with dicyandiamide, sarcosine, methyltaurine, N-ethylanthranic acid-5-sulfonic acid, monoethanolamine, jetanolamine, guanidine, etc.

For the above diazo compound, the coupler is a diazo compound (
diazonium salt) to form a pigment; specific examples include resorcin, phloroglucin, sodium 2,3-hydroxynaphthalene-6-sulfonate, l-hydroxy-2-naphthoic acid morpholinopropylamide, 1 .5-dihydroxynaphthalene, 2,
3-dihydroxynaphthalene, 2,3-dihydroxy-
6-sulfanylnaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-hydroxy-
3-naphthoic acid-2°-methylamide, 2-hydroxy-3-naphthoic acid ethanolamide, 2-hydroxy-
3-naphthoic acid octylamide, 2-hydroxy-3-
naphthoic acid-N-dodecyl-oxy-propylamide,
2-Hydroxy-3-naphthoic acid tetradodecylamide, acetanilide, acetoacetanilide, benzoylacetanilide, 1-phenyl-3-methyl-5-pyrazolone, 2,4-bis(benzoylacetamino) toluene, 1,3-bis( pivaloylacetaminomethyl)benzene, 1-(2°, 4゛6°, -trichlorophenyl)-3-benzamido-5-pyrazolone, 1-(2
° 4° 6"-Trichlorophenyl)-3-anilino-5-pyrazolone, l-phenyl-3-phenylacetamido-5-pyrazolone, etc. Furthermore, by using two or more of these couplers in combination, any color tone can be obtained. images can be obtained.

In photosensitive and thermosensitive materials (hereinafter referred to as diazo thermosensitive layers) whose color forming system is a combination of a diazo compound and a coupler, a basic substance is added as necessary to make the system basic and promote the coupling reaction. be able to.

As these basic substances, used are sparingly water-soluble or water-insoluble basic substances and substances that generate alkali upon heating.

Basic substances include inorganic and organic ammonium salts,
organic amines, amides, urea and thiourea and their derivatives,
Examples include nitrogen-containing compounds such as thiazoles, virols, pyrimidines, piperazines, guanidines, indoles, imidazoles, imidacillines, triazoles, morpholines, piperidines, amidines, formazines, and pyridines. . These basic substances are 2
More than one species can be used in combination.

The electron-donating dye precursor used as another coloring agent in the present invention has the property of donating electrons or accepting protons such as acids to develop color, and is not particularly limited, but usually Compounds that are substantially colorless and have partial skeletons such as lactones, lactams, sultones, spiropyrans, esters, and amides, and whose partial skeletons open or cleave when contacted with a color developer are used. Specific examples include crystal violet lactone, benzoylleucomethylene blue, malachite green lactone, rhodamine B lactam, 1,3.3-)dimethyl-6'-ethyl-8'-butoxyindolinobenzospirobilane, and the like.

The color developer for these color formers can be appropriately selected from known ones and used. For example, the color developer for leuco dyes includes phenolic compounds, sulfur-containing phenolic compounds, carboxylic acid compounds, Examples include sulfone-based compounds, urea-based or thiourea-based compounds, and details thereof can be found, for example, in Paper and Pulp Technology Times (I985).
It is described on pages 49-54 and 65-70. Among these, those with a melting point of 50''C to 250°C are particularly preferred, and among them, phenols and organic acids that are poorly soluble in water and have a melting point of 60°C to 200°C are preferred.When two or more color developers are used in combination. is preferable because it increases solubility.

Among the color developers used in the present invention, particularly preferred ones are represented by the following general formulas (If) to (V).

m=o~2, n=2~11 (Ill) Tyl, heptyl and octyl groups are preferred.

R9 is a hydrogen atom or a methyl group, and n is 0-2.

(V) R1 is an alkyl group, an aryl group, an aryloxyalkyl group or an aralkyl group, with methyl and butyl groups being particularly preferred.

R1 is an alkyl group, especially a butyl group, pen R1l+
is an alkyl group, an aralkyl group or an aryloxyalkyl group.

In the present invention, the diazo compound and the coupler or the electron-donating dye precursor and the color developer are prevented from coming into contact with each other at room temperature (fogging prevention), and from the viewpoint of shelf life (fogging prevention), and also from the viewpoint of color development with the desired impression heating energy. From the viewpoint of controlling the color development sensitivity, it is preferable to microcapsule at least one of the materials essential for the color reaction.

In this case, particularly preferred microcapsules are those that prevent contact between the substances inside and outside the capsule at room temperature due to the substance isolation effect of the microcapsule wall, and whose permeability to substances increases only when heated above a certain temperature; By appropriately selecting the capsule core material, additives, etc., the permeation start temperature can be freely controlled. The transmission start temperature in this case corresponds to the glass transition temperature of the capsule wall (for example, Japanese Patent Application Laid-Open No. 59-91438
No. etc.).

In order to control the glass transition point specific to the capsule wall, it is necessary to change the type of capsule wall forming agent. Examples of the wall material of the microcapsule include polyurethane, polyurea, polyester, polycarbonate, urea-formaldehyde resin, melamine resin, polystyrene, styrene methacrylate copolymer, styrene-acrylate copolymer, gelatin, polyvinylpyrrolidone, polyvinyl alcohol, etc. . Among the above-mentioned polymeric substances, polyurethane, polyurea, polyamide, polyester, polycarbonate, etc. are preferred, and polyurethane and polyurea are particularly preferred.

In the present invention, two or more of these polymeric substances can also be used in combination.

The microcapsules used in the present invention are produced by emulsifying a core material containing a diazo compound, a coupler, an electron-donating dye precursor, or a color developer, and then forming a wall of a polymer material around the oil droplets. Microencapsulation is preferred, in which case the reactant forming the polymeric substance is added inside and/or outside the oil droplets. For details about microcapsules that can be preferably used in the present invention, such as a preferred method for producing microcapsules, see
For example, it is described in JP-A-59-222716.

Here, the organic solvent for forming oil droplets can generally be appropriately selected from high boiling point oils.

When making microcapsules, they can be made from an emulsion containing 0.2% by weight or more of the component to be microencapsulated.

The amount of the material involved in the coloring reaction is 0.00% of the coupler per 1 part by weight of the diazo compound. It is preferable to use 1 to 10 parts by weight of the chlorinated substance and 0.1 to 2011 parts by weight of the chlorinated substance. On the other hand, for 1 part by weight of the electron-donating dye precursor,
0.3 to 160 parts by weight of color developer, preferably 0.3 to 8 parts by weight
Preferably, 0 part by weight is used.

The preferred microcapsules produced as described above are different from those that are destroyed by heat or pressure as used in conventional recording materials, and the reactive substances contained in the core and outside of the microcapsules are Sometimes it can penetrate through the microcapsule wall and react.

On the other hand, the organic boron compound anion salt of the organic cationic dye represented by the general formula (I) is a substance that has been colored from the beginning, but it uses an organic cationic dye and an organic boron compound anion, Either homogeneously mix the two in an organic solvent, or use European Patent No. 223.587A1.
It can be produced by referring to the method described in No.

In the present invention, organic cationic dyes include, for example, cationic methine dyes, polymethine dyes, cyanine dyes, preferably cyanine, carbocyanine, hemicyanine, azomethine dyes; carbonium dyes, preferably triarylmethane dyes, xanthine dyes, acridine dyes, and more preferably is rhodamine; one or two dyes selected from quinoneimine dyes, preferably azine dyes, oxazine dyes, thiazine dyes; quinoline dyes; thiazole dyes, etc.
More than one species can be used in combination.

As the above-mentioned organic cationic dye, commercially available products known in the industry can be used. Examples of these dyes include:
For example, the section on basic dyes in the Dye Handbook edited by the Organic Chemistry Society, and ``Theory of Photographic Processes'' by T. H. James, published by Macmillan Publishing Co., Ltd. (I.

rThe Theory of by H0 James
the PhotographicProcessJ
Macmillan Publishing Co.
Inc.) 1977 CMC Publishing, pp. 1-3, 18
9-206 pages, 401-413 pages, Japanese Patent Application Publication No. 59-18
Examples include those described in No. 9340 and European Patent No. 223587A1.

Among the above dyes, dyes particularly useful in the present invention are cyanine dyes and xanthine dyes. Specific examples of cyanine dyes useful in the present invention include dyes represented by the following general formula (Vl). .

General formula (Vl) In formula 2. ．． 2. is a heterocyclic nucleus commonly used in cyanine dyes, especially a thiazole nucleus, a thiazoline nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, an oxazole nucleus, an oxazoline nucleus, a benzoxazole nucleus, a naphthoxazole nucleus, a tetrazole nucleus, a pyridine nucleus, a quinoline nucleus, and an imidacillin. These nuclei represent atomic groups necessary to complete a nucleus, imidazole nucleus, benzimidazole nucleus, naphthoimidazole nucleus, selenazoline nucleus, selenazole nucleus, benzoselenazole nucleus, naphthoselenazole nucleus, or indolenine nucleus. Lower alkyl groups such as halogen atoms, phenyl groups, hydroxyl groups, alkoxycarbonyl groups, alkylsulfamoyl groups, alkylcarbamoyl groups, acetyl groups, acetoxy groups, cyano groups, trichloromethyl groups, trifluoromethyl groups, nitro groups etc. may be substituted.

t, , L, or t represents a methine group or a substituted methine group. Examples of the substituted methine group include methine groups substituted with lower alkyl groups such as methyl group and ethyl group, phenyl group, substituted phenyl group, aralkyl group such as methoxy group, ethoxy group, and phenethyl group.

L, and R□ and R1! , furthermore, when m,=3, Lz
I! : L* may be alkylene bridged to form a 5- or 6-membered ring.

R□ and Ro are lower alkyl groups (preferably carbon numbers 1 to 1)
8 alkyl group), carboxy group, sulfo group, hydroxy group, halogen atom, alkoxy group having 1 to 4 carbon atoms,
An alkyl group having a substituent such as a phenyl group or a substituted phenyl group (preferably the alkylene moiety is C7 to C3)
It is. For example, β-sulfoethyl, T-sulfopropyl, T-sulfobutyl, δ-sulfobutyl, 2-(2(
3-Sulfopropoxy)ethoxy]ethyl, 2-hydroxysulfopropyl, 2-chlorosulfopropyl, 2-
Methoxyethyl, 2-hydroxyethyl, carboxymethyl, 2-hydroxyethyl, 2,2,3.3. -tetrafluoropropyl, 3.3.3-trifluoroethyl; allyl! , represents a substituted alkyl group commonly used as the N-substituent of cyanine dyes. m+ represents 1.2 or 3, X- represents the above structural formula (I)
represents a boron compound anion.

Specific examples of xanthine dyes useful in the present invention include dyes represented by the following general formula (■).

General formula (■) R31, R3t, R33, and R24 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group,
- represents the boron compound anion of the above structural formula (I), Y
represents a hydrogen atom, an alkyl group, an aryl group or an alkali metal.

Examples of preferred organic boron compound anion salts of organic cationic dye compounds that can be used in the present invention are listed below, but the present invention is not limited thereto.

/\ 3゜ O B (nC4H9)4 B (nC4H0)4 B (n04H6)4 C7H□5 7H15 ne (n C4H9) 4 5゜ B (nC, Ho) s (nc 4H9) 4 10° still, The organoboron compound anion in the above compound side is B- -(nC4 Hri Besides, for example etc. can be cited as specific examples.

In the present invention, it is preferable that the organic boron compound anion is present in the same molar ratio or in a slight excess with respect to the organic cationic dye, and it is particularly preferable that the molar ratio is within the range of 1:1 to 1:2.

These organic boron compound anion salts of organic cationic dyes are spectrally sensitized when the organic cationic dye absorbs light of the corresponding wavelength, so photobleaching progresses and organic cationic dyes are produced. The color of the sex pigment is erased.

However, if the carbon-boron bond of the anion of the boron compound is cut in advance, the photobleaching is not performed, so the color of the organic cationic dye compound is not erased and the coloring caused by the color is fixed.

Therefore, a thermal image can be recorded by applying a thermal signal to break the carbon-boron bond and then irradiating the entire surface with light.

Next, a compound capable of breaking one or more carbon-boron bonds used for the above-mentioned thermal recording will be described in detail.

The compounds used in the present invention that can break one or more carbon-boron bonds (hereinafter referred to as fixing agents) include organic carboxylic acids (such as acetic acid, stearic acid, salicylic acid, and their derivatives), inorganic acids ( (e.g. nitric acid, sulfuric acid, hydrobromic acid, hydrochloric acid, hydrofluoric acid, sulfamic acid and their salts), organic acids other than organic carboxylic acids (e.g. sulfonic acid, sulfonic acid, fluorinated and perfluorinated carboxylic acids) (acids and their derivatives, etc.), phenols, quinones, bisimidazole compounds, peroxides, and compounds containing metal ions that are more easily reduced than ferric ions.

Next, specific examples of preferred compounds among the above compounds will be given, but the present invention is limited thereto. 5゜Bu Bu 3゜13゜PF e 10゜A s F 6e 12゜tBu.

bF--BuQ These compounds can be used alone or in combination of two or more.

When these compounds come into contact with the organic boron compound anion salt of the organic cationic dye, the carbon-boron bond of the organic boron compound is severed, so that even if the organic cationic dye is irradiated with light thereafter, the color of the organic cationic dye is no longer erased. Therefore, in order to perform thermal recording, it is necessary to bring the two into contact for the first time by applying heat.

Therefore, in the present invention, at least one of the fixing agent and the organic boron compound anion salt of the organic cationic dye is encapsulated in microcapsules. When the fixing agent is not encapsulated in microcapsules, it is preferable to disperse it as a solid using a sand mill or the like, or to dissolve it in oil and then emulsify it.

In the case of solid dispersion, it is dispersed in a water-soluble polymer solution having a concentration of 2 to 30% by weight. The preferred dispersed particle size is no greater than a loum. Preferred water-soluble polymers include the water-soluble polymers used in making the microcapsules described above. Regarding emulsification and dispersion, please refer to the patent application No. 62-75, 4
This can be done by referring to the method and materials described in the specification of No. 09.

The fixing agent may be used in an amount of 1 to 100 times the molar amount of the organic boron compound anion, and in particular, in the present invention, it is also possible to use a coloring aid in a molar amount of 1 to 10 times the amount of the organic boron compound anion.

The color development aid that can be used in the present invention is a substance that increases the color density during heat color development or lowers the minimum color development temperature, and is used to melt electron-donating dye precursors, color developers, fixing agents, etc. By lowering the softening point of the capsule wall, the electron-donating dye precursor reacts with the developer, and the organic boron compound anion salt of the organic cationic dye compound reacts with the fixing agent. It is for making.

Coloring aids include phenolic compounds, alcoholic compounds, amide compounds, sulfonamide compounds, etc.
Specific examples include p-tert-octylphenol, p-benzyloxyphenol, p-,i+ phenyl cybenzoate, benzyl carbanylate, phenethyl carbanylate, hydroquinone dihydroxyethyl ether,
Compounds such as xylylene diol, N-hydroxyethyl-methanesulfonic acid amide, and N-phenyl-methanesulfonic acid amide can be mentioned. These may be contained in the core material of the microcapsule, or may be added outside the microcapsule as an emulsified dispersion.

In the present invention, in order to obtain a substantially transparent photosensitive and thermosensitive layer, a diazo compound or an electron-donating dye precursor is contained in microcapsules, while a coupler or color developer is an organic compound that is sparingly soluble or insoluble in water. After dissolving it in a solvent, it is preferably used in the form of an emulsified dispersion by mixing it with an aqueous phase containing a surfactant and having a water-soluble polymer as a protective colloid. It is preferable that the anion salt of the boron compound is contained in microcapsules, and the fixing agent is used in the form of an emulsified dispersion as in the case of the color developer and the like.

The organic solvent used in this case can be appropriately selected from high boiling point oils. In addition to esters, preferred oils include compounds represented by the following general formulas (■) to (X), triallylmethane (e.g., tritolylmethane, tolyldiphenylmethane), and terphenyl compounds (e.g., terphenyl). , alkyl compounds (e.g. terphenyl), alkylated diphenyl ethers (e.g. propyl diphenyl ether), hydrogenated terphenyl (e.g. hexahydroterphenyl),
Examples include diphenyl ether.

In the present invention, it is preferable to use esters among these from the viewpoint of emulsion stability of the emulsified dispersion.

(■) In the formula, R' is hydrogen or an alkyl group having 1 to 18 carbon atoms, R
z represents an alkyl group having 1 to 18 carbon atoms t, p', q
' represents an integer from 1 to 4, and the total number of alkyl groups is 4
No more than 100 pieces.

In addition, the alkyl group of R1 and Rt is preferably an alkyl group having 1 to 8 carbon atoms.

(IX) In the formula, R3 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and R4 represents an alkyl group having 1 to 12 carbon atoms. n is l
Or represents 2.

p t and q t represent an integer of 1 to 4; in the case of n-1, the total number of alkyl groups is within 4, and n-2
When , the total number of alkyl groups is 6 or less.

/ / , /' / (X) In the formula, Rs and R& are hydrogen atoms or carbon atoms 1 to 18
represents the same or different alkyl groups.

m represents an integer from 1 to 13, P3, q3 & m represents an integer from 1 to 3, and the total number of alkyl groups is within 3.

In addition, the alkyl group of R' and R'' is particularly preferably an alkyl group having 2 to 4 carbon atoms.

Examples of the compound represented by formula (■) include dimethylnaphthalene, diethylnaphthalene, and cyanopropylnaphthalene.

Examples of the compound represented by formula (IX) include dimethylbiphenyl, diethylbiphenyl, diinopropylbiphenyl, and diisoptylbiphenyl.

Examples of compounds represented by formula (X) include l-methyl-1
-dimethylphenyl-1-phenylmethane, 1-ethyl-1-dimethylphenyl-1-phenylmethane, and 1-propyl-1-dimethylphenyl-1-phenylmethane.

Examples of esters include phosphate esters (e.g., triphenyl phosphate, tricresyl phosphate, butyl phosphate, octyl phosphate, talesyl diphenyl phosphate), phthalate esters (
Dibutyl phthalate, 2-ethylhexyl phthalate, ethyl phthalate, octyl phthalate, butylbenzyl phthalate) dioctyl tetrahydrophthalate, benzoic acid ester (ethyl benzoate, propyl benzoate, butyl benzoate, isopentyl benzoate, benzoic acid) benzyl acid), ethyl abietate (ethyl abietate, benzyl abietate), dioctyl adipate, isodecyl succinate, dioctyl azelaate, oxalate ester (diptyll chelate, dibentyl oxalate), diethyl malonate, maleate ester ( dimethyl maleate, diethyl maleate, dibutyl maleate), tributyl citrate, sorbate esters (methyl sorbate, ethyl sorbate, butyl sorbate), sebacate esters (dibutyl sebacate, dioctyl sebacate), ethylene glycol ester (formic acid monoesters and diesters, butyric acid monoesters and diesters, lauric acid monoesters and diesters, valmitic acid monoesters and diesters, stearic acid monoesters and diesters, oleic acid monoesters and diesters), triacetin, diethyl carbonate, diphenyl carbonate , ethylene carbonate, propylene carbonate, boric acid esters (tributyl borate, tripentyl borate), and the like. Among these, when tricresyl phosphate is used alone or in combination, the emulsion dispersion stability of the color developer is particularly good, and therefore it is preferable.

It is also possible to use the above oils together or with other oils.

In the present invention, an auxiliary solvent may be added to the above-mentioned organic solvent as a low boiling point dissolution aid. Particularly preferred examples of such co-solvents include ethyl acetate, isopropyl acetate, butyl acetate and methylene chloride.

In the case of a diazo coloring system, it is particularly preferable to co-dissolve a phenolic compound and a salicylic acid derivative metal salt together with the coupler in the organic solvent in order to stabilize the emulsified dispersion of the coupler.

The water-soluble polymer to be contained as a protective colloid in the aqueous phase mixed with the oil phase containing these components can be appropriately selected from known anionic polymers, nonionic polymers, and amphoteric polymers. However, polyvinyl alcohol, gelatin, cellulose derivatives, etc. are preferred, and partially saponified polyvinyl alcohol is particularly preferred.

Further, as the surfactant to be contained in the aqueous phase, a surfactant that does not cause precipitation or aggregation by acting with the protective colloid can be appropriately selected from anionic or nonionic surfactants.

Preferred surfactants include sodium alkylbenzene sulfonate, sodium alkyl sulfate, dioctyl sodium sulfosuccinate, polyalkylene glycol (
For example, polyoxyethylene nonylphenyl ether)
etc. can be mentioned.

The emulsified dispersion in the present invention is produced by mixing an oil phase containing the above components and an aqueous phase containing a protective colloid and a surfactant using means commonly used for fine particle emulsification, such as high-speed stirring and ultrasonic dispersion. It can be easily dispersed and obtained.

The oil droplet size (diameter) of this emulsified dispersion has a haze of 60
7μ to obtain a substantially transparent photosensitive and thermosensitive layer of
It is preferably less than m, more preferably from 0.1 to
It is within the range of 5 μm.

Further, the ratio of the oil phase to the aqueous phase (oil phase weight/aqueous phase weight) is preferably 0.02 to 0.6, more preferably 0.1.
~0.4. If it is less than 0.02, the aqueous phase will be too large and diluted, making it impossible to obtain sufficient color development, while if it is more than 0.6, the viscosity of the liquid will increase, resulting in inconvenience in handling and a decrease in stability of the coating liquid.

The heat-sensitive recording material of the present invention can be coated using a suitable binder.

Binders include polyvinyl alcohol, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, gum arabic, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylic acid ester, ethylene-vinyl acetate, etc. Various emulsions such as polymers can be used. The amount used is 0.5 to 5 g/rrf in terms of solid content.

In the present invention, in addition to the above materials, citric acid, tartaric acid, oxalic acid, boric acid, phosphoric acid, pyrophosphoric acid, etc. can be added as acid stabilizers.

In the present invention, when a transparent support is used as the support, the recorded image can be seen as a transmitted image or a reflected image from one side of the transparent support, but especially in the latter case, the back side of the background part is visible. If the image becomes transparent, the image will be dull, so a layer containing a white pigment may be additionally coated on the top of the light- and heat-sensitive layer or on the back side of the transparent support to make it look white. Examples of preferred white pigments include: talc,
Calcium carbonate, calcium sulfate, magnesium carbonate,
Examples include magnesium hydroxide, alumina, synthetic silica, titanium oxide, barium sulfate, kaolin, calcium silicate, and urea resin.

The coating amount of the photosensitive and thermosensitive layer is 3 g/po to 20 g/po, especially 5 g/po.
Preferably between g/rd and 15 g/nf, 3
Sufficient sensitivity cannot be obtained below g10f, and 20g/nf
Even if more coating is applied, no improvement in quality will be seen, and this will be disadvantageous in terms of cost.

It is also possible to further combine known heat-sensitive layers.

In the present invention, it is preferable to provide an intermediate layer between the heat-sensitive layers from the viewpoint of improving the shelf life of the heat-sensitive recording material, the shelf life of recorded images, and color separation. It is preferable to use a layer formed by gelling a polymer with polyvalent cations.

Preferred water-soluble polyanionic polymers are polymers having carboxyl groups, sulfonic acid groups, and phosphoric acid groups. Water-soluble polyanionic polymers having carboxyl groups are particularly preferred. Examples of preferred water-soluble polyanionic polymers include natural or Synthetic multi-W gums (
Examples include alginate alkali metal salt, guar gum 1
, gum arabic, carrageenan, pectin, gum tragacanth, xanthine gum, etc.), polymers of acrylic acid or methacrylic acid and copolymers thereof, polymers of maleic acid or phthalic acid and copolymers thereof, cellulose derivatives such as carboxymethyl cellulose, The molecular weight of the water-soluble polyanionic polymer, which includes gelatin, agar, etc., and which is preferably an alginate alkali metal salt, is 5,000 to 10.
．． 000 is preferred, particularly from the viewpoint of barrier properties and manufacturing suitability aimed at in the present invention, from 10.000 to 40.00.
000 is preferred, and examples of the polyvalent cation include salts of alkaline earth metals and other valent metals (e.g. CaCj!, B
aCj! m,Aj! *(SOa)3, ZnSO4, etc.)
, polyamines (eg, ethylenediamine, diethylenetriamine, hexamethylenediamine, etc.), and polyimines are preferred.

Another preferred example of the intermediate layer in the present invention is an ionic complex of a water-soluble polyanionic polymer and a water-soluble polycationic polymer. In this case, the various water-soluble polyanionic polymers described above can be used as the water-soluble polyanionic polymer.

Preferred water-soluble polycationic polymers include proteins having a plurality of reactive nitrogen-containing cationic groups, polypeptides such as polylysine, polyvinylamines, polyethyleneamines, polyethyleneimines, and the like.

When making an intermediate layer using these materials, one of the materials should be used as the first layer to prevent rapid gelation during application.
It is preferable to apply the material by including it in the coloring layer or the second coloring layer, but the temperature and pH may be further adjusted, or one material may be contained in the first coloring layer and the other material may be included in the second coloring layer. It is also possible.

The preferred coating amount of the intermediate layer is 0.05 g/m” to 5 g
/ m”, more preferably 0.1 g/m: ~
2g/m dew.

In the light and heat sensitive recording material of the present invention, in order to improve scratch resistance and solvent resistance and ensure transparency of the light and heat sensitive layer,
It is preferable to provide a transparent protective layer on the photosensitive/thermosensitive layer. The transparency of the photosensitive/thermosensitive layer of the present invention is 60 when expressed in terms of haze (%) (measured with an integrating sphere HTR meter manufactured by Nippon Seimitsu Kogyo ■). % or less, preferably 40% or less, more preferably 30% or less. However, the transparency of an actual photosensitive/thermosensitive layer test sample is greatly influenced by light scattering due to minute irregularities on the surface of the photosensitive/thermosensitive layer. Therefore, when measuring the inherent transparency of the photosensitive/thermosensitive layer, which is a problem in the present invention, that is, the transparency inside the photosensitive/thermosensitive layer, using a haze meter, a simple method is to attach a transparent adhesive tape on the photosensitive/thermal layer. Evaluation is made using the measured values with almost all surface scattering removed.

As mentioned above, the protective layer that may be provided on the photosensitive and thermosensitive layer is preferably made of silicon-modified polyvinyl alcohol and colloidal silica because it has good transparency.

The silicon-modified polyvinyl alcohol used in the present invention is
There are no particular limitations as long as the silicon atom is contained in the molecule, but usually the silicon atom contained in the molecule is an alkoxy group, an acyloxyl group, a hydroxyl group obtained by hydrolysis, etc., or an alkali metal salt thereof, etc. It is preferable to use those having reactive substituents.

Details of the method for producing modified polyvinyl alcohol containing silicon atoms in the molecule are disclosed in JP-A-58-19318.
It is described in Publication No. 9.

The colloidal silica used in the present invention is used as a colloidal solution in which ultrafine particles of silicic anhydride are dispersed in water using water as a dispersion medium. The particle size of the colloidal silica is preferably 110m1I to 100mtIm5 with a specific gravity of 1.1 to 1.3. In this case, the pH value of the colloidal solution is preferably about 4 to about 1O.

When the above-mentioned protective layer is provided on the surface of the light- and heat-sensitive recording material, the surface scattering phenomenon is suppressed in the same way as when the above-mentioned transparent adhesive tape is applied, and surprisingly, the transparency of the protective layer is extremely good. As a result, the transparency of the entire light- and heat-sensitive recording material can be further and significantly improved. In addition, when this protective layer is provided as the outermost layer of the recording material, the mechanical strength of the surface of the light and heat sensitive layer is improved, and when it is provided as an intermediate layer between laminated layers, it prevents unnecessary color mixing between the eyebrows. It can also play an additional role.

A suitable blending ratio of the silicon-modified polyvinyl alcohol and colloidal silica is 0.5 to 3 parts by weight, more preferably 1 to 2 parts by weight, of colloidal silica per 1 part by weight of silicon-modified polyvinyl alcohol. If the amount of colloidal silica used is less than 0.5 parts by weight, the effect of improving transparency will be small, and if it is used more than 3 parts by weight, cracks will occur in the protective layer, and the transparency will be reduced.

The protective layer may further contain one or more polymers. Specific examples of polymers that can be used in combination include methylcellulose, carboxymethylcellulose, hydroxymethylcellulose, starches, gelatin, gum arabic, casein, and styrene-maleic anhydride. Water-soluble polymers such as acid copolymer hydrolyzate, styrene-maleic anhydride copolymer half ester hydrolyzate, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, polyacrylamide derivatives, polyvinylpyrrolidone, sodium polystyrene sulfonate, sodium alginate, etc. and water-insoluble polymers such as styrene-butadiene rubber latex, acrylonitrile-brassene rubber latex, methyl acrylate-butadiene rubber latex, and polyvinyl acetate emulsion. The amount used in combination is preferably 0.01 to 0.5 parts by weight per 1 part by weight of silicon-modified polyvinyl alcohol.

The protective layer contains pigments, metallic soaps, waxes, and crosslinkers for the purpose of improving mating properties with the thermal head during heat-sensitive recording or heating rollers during heat fixing after photosensitive recording, and improving the water resistance of the protective layer. agent etc. are added.

Pigments include zinc oxide, calcium carbonate, barium sulfate, titanium oxide, lithopone, talc, Shinpaku, kaolin, aluminum hydroxide, amorphous silica, etc., and the amount of these additives ranges from 0°005 to 0.005% of the total weight of the polymer. The amount is 0.2 times, particularly preferably 0.01 to 0.05 times. If the amount is less than 0.005 times, it is ineffective in improving the matching property with the thermal head during heat-sensitive recording or the heating roller during heat fixing after heat-sensitive recording, and if the amount is more than 0.2 times, the light and heat sensitive recording material A decrease in transparency and sensitivity significantly impairs its commercial value.

Metal soaps include emulsions of higher fatty acid metal salts such as zinc stearate, potassium stearate, aluminum stearate, etc., and the proportion thereof is 0.5 to 20% by weight, preferably 1 to 10% by weight of the total weight of the protective layer. added in quantity. Waxes include emulsions such as paraffin wax, microcrystalline wax, carnauba wax, methylolstearamide, polyethylene wax, and silicone, and the proportion thereof is 0.5 to 40% by weight, preferably 1 to 20% by weight of the total weight of the protective layer. is added in an amount of

In addition, in order to uniformly form a protective layer on the photosensitive and thermosensitive layer,
A surfactant is added to the coating solution for forming the protective layer. Surfactants include sulfosuccinic acid-based alkali metal salts, fluorine-containing surfactants, etc. Specifically, sodium salts or ammonium salts of di(2-ethylhexyl)sulfosuccinic acid, di(n-hexyl)sulfosuccinic acid, etc. etc.

In addition, a surfactant, a polymer electrolyte, etc. may be added to the protective layer to prevent charging of the photosensitive and thermosensitive recording material.
The solid coating amount of the protective layer is usually preferably 0.2 to 5 g/nf, more preferably 1 g to 3 g/nf.

A support such as paper or a synthetic resin film is used in the light and heat sensitive recording material of the present invention.

The paper used for the support is thermally extracted p) 1 sized with a neutral sizing agent such as an alkyl ketene dimer.
Use of neutral paper No. 6 to No. 9 (described in JP-A-55-14281) is advantageous in terms of storage stability over time.

In order to prevent the penetration of the coating liquid into the paper and to improve the contact between the light and heat sensitive recording layer and the thermal head during heat sensitive recording or the heating roller during heat fixing after light sensitive recording, there is a
The paper described in No. 7-116687 and having a Bekk smoothness of 90 seconds or more is advantageous.

Also, paper with an optical surface roughness of 8 μm or less and a thickness of 40 to 75 μm as described in JP-A-58-136492, and paper with a density of 0°9 g/cm3 or less and optical contact as described in JP-A-58-69097. Paper with a ratio of 15% or more, JP-A-58-69
Canadian Standard Freeness (JIS P81) described in No. 097
Paper made from pulp beaten to 400 cc or more in 21) to prevent penetration of coating liquid, JP-A-58-65
695, the glossy side of base paper made by a Yankee machine is used as the coated surface to improve the color density and resolution, and the method described in JP-A-59-35985, in which the base paper is subjected to corona discharge treatment. Papers with improved coatability can also be used in the present invention with good results. In addition to these, any support commonly used in the field of heat-sensitive recording paper can be used as the support of the present invention.

The heat-sensitive layer can be laminated on one side of the transparent support or can be provided on both sides.

Next, the transparent support used in the present invention will be described.

The transparent supports mentioned here include polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate films, polystyrene films, polypropylene films, polyolefin films such as polyethylene, etc. It can be used alone or in combination.

The thickness of the transparent support used is 20 to 200 um, particularly preferably 50 to 10,100 um.

In the present invention, an undercoat layer can be provided between the transparent support and the photosensitive/thermosensitive layer in order to enhance the adhesion between the two layers.
Gelatin, synthetic polymer latex, nitrocellulose, etc. are used as the material for the undercoat layer. The coating amount of the undercoat layer is preferably in the range of 0.1g/rd to 2°Og/rrt, particularly 0°2g/rrf to 1.0g/rrt. Qg/rrf
A range of is preferred.

o. If it is less than Ig/rrl, the adhesion between the support and the photosensitive/thermosensitive layer will not be sufficient, and 2. Even if it is increased beyond Og/rrf, the adhesive force between the support and the photosensitive/thermosensitive layer has reached saturation, which is disadvantageous in terms of cost.

The undercoat layer should not be hardened because the image quality of the light and heat sensitive layer may deteriorate if the undercoat layer swells due to the water contained in the light and heat sensitive layer when the light and heat sensitive layer is coated thereon. It is desirable to cure the resin using an agent.

The amount of these hardeners added is based on the weight of the base coat material.
An appropriate addition amount can be selected in the range of 0.20% by weight to 3.0% by weight depending on the coating method and desired degree of curing.

Depending on the hardening agent used, if necessary, the pH of the solution can be made alkaline by adding caustic soda or the like, or the pH of the solution can be made acidic by adding citric acid or the like.

It is also possible to add an antifoaming agent to eliminate foam generated during coating, or to add an activator to improve liquid leveling and prevent coating streaks.

It is also possible to add an antistatic agent if necessary.

Furthermore, before applying the undercoat layer, it is desirable to activate the surface of the support by a known method.

Activation treatment methods include acid etching treatment,
Flame treatment using a gas burner, corona treatment, glow discharge treatment, etc. are used, but from the point of view of cost or simplicity, U.S. Pat.
No. 846.727, No. 3.549.406, No. 3
, 590, 107, etc., is most preferably used.

The light- and heat-sensitive recording material of the present invention only needs to have the above-mentioned substantially transparent light- and heat-sensitive layer on the support, and even if the heat-sensitive layer is laminated on one side of the support, or on both sides of the support. It is possible to provide a heat-sensitive layer on the support, and it is not only possible to directly provide a photosensitive and heat-sensitive layer that can each develop a different color on the support, but also to provide two or more layers via the above-mentioned protective layer or undercoat layer. Furthermore, an IJI selected from known photosensitive layers, heat-sensitive layers, and light-sensitive heat-sensitive layers is provided on the support, and the substantially transparent IJI described herein that can develop a color different from that of this layer is further provided on the support. It is also possible to provide a photosensitive and thermosensitive layer, etc.
Various embodiments are possible depending on the use and purpose.

In the case of laminating a substantially transparent heat-sensitive layer whose color forming system is a combination of a diazo compound and a coupler or a combination of an electron-donating dye precursor and a color developer according to the present invention and a photobleachable heat-sensitive layer, the stacking order is as follows: This is optional because the skin of the photobleached heat-sensitive layer can be made substantially transparent after photobleaching.

The coating liquid according to the present invention can be applied by a generally well-known coating method,
For example, dip coating method, air knife coating method, curtain coating method, roller coating method, doctor coating method,
Coating can be performed by a wire barcode method, a slide coating method, a gravure coating method, or an extrusion coating method using a hopper as described in US Pat. No. 2,681,294. U.S. Pat. No. 2,761.791 and U.S. Pat. No. 3,508,947, as appropriate.
No. 2,941,898, and No. 3゜526.
Specification No. 528, Yuji Harasaki, "Coating Engineering" 25
It is also possible to apply it simultaneously in two or more layers using the method described in page 3 (published by Asakura Shoten in 1973), etc., and an appropriate method can be selected depending on the amount of coating, coating speed, etc. .

Adding pigment dispersants, thickeners, flow modifiers, antifoaming agents, foam inhibitors, mold release agents, colorants, etc. to the coating liquid used in the present invention as necessary will not impair the properties. I have no qualms as far as it goes.

The light-sensitive and heat-sensitive layer of the present invention can be used for copying by image exposure using light in the photodegradation wavelength range of a photodegradable diazo compound or in the wavelength range absorbed by a photobleaching organic cationic dye, or in a light valve such as a liquid crystal light pulp. Optical recording is performed by point exposure using a heating roller, and then the photosensitive layer is uniformly heated to a temperature higher than the thermal melting temperature of the heat-sensitive material containing microcapsules to develop color in the unexposed areas, thereby producing a fixed image. The image is fixed by making the dye in the unexposed or unexposed areas photoinhibitable. In addition, after applying heat with a thermal head, the entire surface is exposed to light in the above wavelength range to decompose the diazo compound in the area where no heat was applied or to decolor the organic cationic dye. Even in this case, a recorded image with excellent fixing properties can be obtained. As the light source for photolysis or photobleaching in this case, various light sources that emit light of the desired wavelength can be used, such as various fluorescent lamps, xenon lamps, xenon flash lamps, mercury lamps of various pressures, and photographic lamps. flash for,
Any number of light sources such as a strobe can be used. Further, in order to make the light irradiation zone compact, the light source section and the light irradiation section may be separated by an optical fiber layer.

The light-sensitive and heat-sensitive layer of the present invention has high photosensitivity during image exposure copying and photobleaching, and can be developed and fixed by low-temperature heating, and has high thermal sensitivity, so it outputs relatively high output after low-temperature and high-speed thermal recording. It can be fixed in a short time with a small light source, and therefore can be used for various types of thermal recording and photosensitive recording.

Furthermore, since the light and heat sensitive recording material of the present invention can have excellent transparency, recorded images with good color image transparency after heat and photosensitive recording can be obtained. Therefore, by using a transparent support, various uses using color transmitted images, such as color display using an overhead projector, become possible.

Furthermore, according to the light and heat sensitive recording material of the present invention, recorded images with excellent background and color image transparency can be obtained, so mixed color reproduction is good when transparent color images are superimposed, and it is also excellent as a multicolor recording material. It is something.

(Effects of the Invention) The coloring system consisting of a combination of an electron-donating dye precursor and a color developer used in the present invention as well as the organic boron anion salt of an organic cationic dye are both easy to select hues, and are compatible with diazo compounds. Both the coloring system consisting of a combination of couplers and the coloring system using an organic boron anion salt of an organic cationic dye can fix an image with light, and furthermore, each heat-sensitive layer can be a heat-sensitive layer with good transparency. Therefore, the multicolor thermosensitive recording material of the present invention can form a multicolor image that is clearer and has better color separation than ever before.

(Example) The present invention will be further explained with reference to Examples below, but the present invention is not limited thereto.

Note that "1 part" indicating the amount added represents "part by weight."

Example 1 Capsule 'A' 10Occ of the following compound diazo compound IR-120B (manufactured by Rohm and Haas (trade name)) was added, stirred for 1 hour, and then filtered to obtain capsule liquid A.

Tricresyl phosphate 6 parts Methylene chloride 12 parts Trimethylolpropane trimethacrylate 18 parts D-11ON (75% by weight ethyl acetate solution)
(manufactured by Takeda Pharmaceutical Co., Ltd. (trade name)) 24 parts were mixed, and polyvinyl alcohol (PVA-21 manufactured by Kuraray ■) was mixed.
7E (trade name)) 63 parts of 8% by weight aqueous solution and 10 parts of distilled water
After adding it to an aqueous solution consisting of 0 parts, it was emulsified and dispersed at 20°C to obtain an emulsion with an average particle size of 2 μm.

The resulting emulsion was stirred at 40°C for 3 hours, then cooled to 20°C, and then amberlite triphenylguanidine CH was added.

(Base) 6 parts 1° 4 parts tricresyl phosphate 10 parts ethyl acetate
A solution of 20 parts of the above composition was added to 170 parts of a 4% by weight aqueous solution of polyvinyl alcohol, mixed, and emulsified at 20°C to obtain a coupler/m2 having an average particle size of 1.5 parts.
An emulsified dispersion of base dispersion A was obtained.

Capsule B-81 Organoboron compound anion salt of organic cationic dye compound B-(nc* H9) 4 (Dye inhibitor 6: Magenta dye) C) Its 0° 41 parts N(CHI) 4°-B(n Ca R9) a to 0.0
8 parts methyl isobutyl ketone 12 parts tricresyl phosphate 15 parts Takenate D-I ION (75% by weight ethyl acetate solution) (manufactured by Takeda Pharmaceutical Co., Ltd. (trade name)) 12 parts were mixed, and 8 parts by weight aqueous polyvinyl alcohol solution, Diethylenetriamine 1
．． It was added to an aqueous solution consisting of 15 parts of a 67% by weight aqueous solution and 30 parts of distilled water, and then emulsified and dispersed at 20°C to obtain an average particle size of la.
An emulsion of m was obtained. Further, the obtained emulsion was stirred continuously at 40° C. for 3 hours, then returned to room temperature and filtered to obtain an aqueous polyurea microcapsule dispersion.

8 parts of fixing agent (a), 4 parts of (b) and 3 parts of (C) represented by the following structural formula were dissolved in 8 parts of 1-phenyl-1-xylylethane and 30 parts of ethyl acetate. The obtained developer solution was mixed with 100 parts of an 8% by weight aqueous solution of polyvinyl alcohol, 150 parts of water, and 0.00 parts of sodium dodecylbenzenesulfonate.
Mix with 5 parts of aqueous solution and emulsify and disperse, particle size 0.5
An emulsified dispersion of micrometers was obtained.

Fixing agent (a) Fixing agent (b) Fixing agent (c) Ca H- L-phenyl-1-xylylethane as electron-donating dye precursor 55 parts Ethyl acetate 55 parts Sumithorpe 2
00 (ultraviolet absorber manufactured by Sumitomo Chemical ■) 2 parts Takenate D-11ON (manufactured by Takeda Pharmaceutical Company Limited (trade name)) 60 parts were mixed to form an aqueous solution consisting of 100 parts of an 8% by weight aqueous solution of polyvinyl alcohol and 40 parts of distilled water. After adding it to the solution, it was emulsified and dispersed at 20°C to obtain an emulsified dispersion with an average particle size of 1 μm.Next, the obtained emulsion was continuously stirred at 40°C for 3 hours to obtain capsule liquid C. Ta.

Sara Wataru Sara Kokanshin: A solution with the same composition as the fixative dispersion was used.

Temporary silica-modified polyvinyl alcohol (PVA made by Kuraray)
R2105) 10% by weight liquid 10 parts Colloidal silica (Snowtex 30 manufactured by Nissan Chemical ■) 30% by weight
Liquid 5 parts Zinc stearate (Hydrin 2-7 made by Chukyo Yushihiga) 30% by weight liquid
A protective layer liquid was obtained by mixing 0.42 parts of a 30% by weight liquid of paraffin wax (Hydrin P-7, manufactured by Middle East Oil Co., Ltd.).

After applying corona treatment to one side of a biaxially stretched polyethylene terephthalate film with a thickness of 75 parts, a mixed solution of 0.1 parts of capsule liquid and 10 parts of color developer dispersion was applied in a dry coating amount. After coating on birch with 6 g/nf, capsule liquid 810
The dry coating amount of a mixture of 10 parts and 10 parts of fixer dispersion was 6 g/
It was applied so that it would look like this.

Next, as an intermediate layer, a 3% aqueous solution of sodium alginate (Snow Algin SH manufactured by Fuji Chemical ■) was applied in a dry coating amount of 0.5.
It was applied so that it was g/po.

Additionally, 6 parts of capsule liquid A, coupler/base dispersion A
After applying a mixture of 5.5 parts of calcium chloride and 0.5 parts of a 20% calcium chloride aqueous solution to a dry coating amount of 6 g/rrT, the protective layer solution was applied to a dry coating amount of 2 g/rrT. death,
I got a record sheet. ! ! ! The fabric was dried using a wire bar and then dried in the open at 50°C.

The resulting recording sheet was thermally printed at low energy (thermal head voltage 13v, printing time 0-2.5m5ec) to obtain a yellow colored image, and then irradiated with light for 10 seconds using a Riff Piece Pardry 100 model, and then printed at medium energy. - (Thermal head IT pressure 13V.

Printing time: 0 to 2.5m5ec) with thermal printing and fluorescent lighting.
Light was irradiated for seconds to obtain a magenta colored image.

Furthermore, thermal printing was performed at high energy (thermal head voltage 17V, printing time θ~2.5m5ec) to obtain a cyan colored image.

The resulting image was a clear, full-color image in three colors: yellow, cyan, and magenta, and was suitable for use as an OHP sheet.

[Brief explanation of the drawing]

FIG. 1 is an example of a cross-sectional view of the heat-sensitive recording material of the present invention. FIG. 2 is a conceptual diagram showing the state of color development when an image is recorded on the heat-sensitive recording material shown in FIG.

Claims (1)

[Scope of Claims] A multicolor heat-sensitive recording material comprising at least a support and three or more heat-sensitive layers each capable of recording images of different hues, at least one of the heat-sensitive layers serving as a coloring component of a thermochromic layer. A combination of a diazo compound and a coupler is used as a color-forming system for the heat-sensitive layer, and a combination of an electron-donating dye precursor and a color developer is used as a color-forming system for at least one other layer, and at least one other layer of the heat-sensitive layer selected from at least one compound selected from organic boron compound anion salts of organic cationic dye compounds represented by the following general formula (I) and compounds capable of breaking one or more carbon-boron bonds. at least 1
A multicolor heat-sensitive recording material that uses a decolorizing system consisting of a combination of a species compound as an image forming system, which comprises destroying at least one or more carbon-boron bonds with an organic boron compound anion salt of the organic cationic dye compound. A multicolor heat-sensitive recording material characterized in that a compound to be obtained is separated from the compound by a wall of a microcapsule. General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. R_1, R_
2, R_3 and R_4 may be a cyclic structure in which two or more of the groups are bonded. ]