JPH01294086A - Multicolor recording material - Google Patents

Abstract

PURPOSE:To enhance developed color density and prevent fogging, by providing at least two color forming layers each of which comprises a diazo compound and a coupler and which form different colors on one side of a base, through an intermediate layer with a specified composition therebetween, to produce a multicolor recording material. CONSTITUTION:An intermediate layer obtained by gelling a water-soluble polyanion polymer by a multivalent cation is provided on one side of a base. At least two color forming layers each of which comprises a diazo compound and a coupler as color forming components and which are developed into colors with different hues are provided on the intermediate layer to produce a multicolor recording material. Preferred examples of the diazo compound include 4-diazo-1-dimethylaminobenzene, and preferred examples of the coupling component include 2-hydroxy-3-naphthoic acid anilide. The base may be a polymer film or the like, the thickness of which is preferably 20-200mum.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multicolor recording material, and particularly to a multicolor recording material that can be thermally recorded with good color separation.

(Prior Art) As the most common method for obtaining multicolor images, silver halide 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.

On the other hand, as a conventional method using a simple heat-sensitive recording method, for example,
No. 9, No. 52-11231, JP-A-54-88135
No. 55-133991, No. 55-133992, etc., a method is known in which a plurality of coloring units are simply added one after another as the printing heating energy increases, and the colors are mixed and the hue changes while becoming muddy. However, in addition, for example, Japanese Patent Publications No. 50-17868, No. 51-5791, No. 57
-14318, No. 57-14319, JP-A-55-
As shown in No. 161688, there is a color-erasing mechanism in which when a color-forming unit with a higher thermal response temperature develops color, a color-erasing agent acts at the same time to erase the color-forming unit that develops color at a lower temperature.

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 color hard copies. 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 a corresponding heat-sensitive coloring layer on the same support. However, in reality, if the applied heating energy is extended to a lower range than before, problems may arise in terms of storage stability (so-called fogging) 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, in the past, the maximum allowable fraction of the applied heating energy was actually about 2 fractions in order to satisfy the color separation property.

Furthermore, in JP-A No. 60-4092, there is a description that each component is dissolved and applied in the same layer in order to improve the transparency of the heat-sensitive coloring layer and improve color reproduction, but in this case, , color development of each component easily occurs even before printing, resulting in so-called capri. 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 inventors of the present invention, as a result of intensive studies to solve the drawbacks of the conventional technology, have found that by providing a substantially transparent color-forming layer on both sides of a transparent support that develops colors in different hues, the present inventors can achieve better heat sensitivity than ever before. It has been found that colored images can be obtained and has already been proposed (Japanese Patent Application No. 75409/1983).

(Problem to be Solved by the Invention) However, in a recording material that has a multi-color recording material mechanism by providing recording layers in layers, it is important to prevent the inconvenient movement of the material in each layer to improve color reproducibility and image quality. It is fundamentally important from the perspective of preservation, etc.

As a result of intensive studies aimed at improving from this perspective, the present inventors obtained extremely good results by using a layer made of a water-soluble polyanionic polymer gelled with polyvalent cations as an intermediate layer between the laminated coloring layers. The present invention was achieved by discovering that this can be done.

Accordingly, a first object of the present invention is to provide a recording material capable of obtaining multicolor images with high color density and little fog.

A second object of the present invention is to develop different hues on one side of the support by a color reaction, at least 21! J
An object of the present invention is to provide an intermediate layer suitable for preventing the material from moving between the eyebrows between the respective coloring layers in a multicolor recording material formed by stacking recording layers.

(Means for Solving the Problems) The above-mentioned aspects of the present invention include at least two color-forming layers containing a diazo compound and a coupler as color-forming components on one side of a support, each of which can develop different hues. This is achieved by a multicolor recording material consisting of multiple layers, which is characterized by providing an intermediate layer formed by gelling a water-soluble polyanionic polymer with polyvalent cations between the coloring layers. It was done.

The diazo compound in the present invention mainly means an aromatic diazo compound, and specifically means compounds such as aromatic diazonium salts, diazosulfonate compounds, and diazoamino compounds. Hereinafter, explanation will be given mainly using diazonium salt as a representative example.

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

Examples of diazonium compounds preferably used in the present invention include 4-diazo-1-dimethylaminobenzene, 4
-Diazo-1-diethylaminobenzene, 4-diazo-
1-dipropylaminobenzene, 4-diazo-1-methylbenzylaminobenzene, 4-diazo-agedibenzylaminobenzene, 4-diazo-1-ethylhydroxyethylaminobenzene, 4-diazo-1-diethylamino-3-methoxy Benzene, 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-ruylmercabuto 2,5-jethoxybenzene, 4-diazo-
1,4-methoxybenzoylamino-2,5-jethoxybenzene, 1-diazo-4-(N,N-dioctylcarbamoyl)benzene, 1-diazo-2-octadecyloxybenzene, 1-diazo-4-(4 -tert-octylphenoxy)benzene, 1-diazo-4-(2,
4-tert-amylphenoxy)benzene, 1-
Diazo-2=(4-tert-octylphenoxy)benzene, ■-Diazo-5-chloro-2-(4-tert
-octylphenoxy)benzene, 1-diazo-2,5
-bis-occudecyloxybenzene, l-diazo-2
. The photolysis wavelength can be changed widely by changing the wavelength.

Specific examples of acid anions include C, Ftn, COO-
(n represents 3 to 9), C-F! -1S Os-
(m represents 2 to 8), (Cj!F!L-tSOz)
Examples include ICH- (f represents 1 to 18), HC(CH3)5CH-CH:18F, -1PF, -, and the like.

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

oc, n9 OC2H5 The diazosulfonate compound that can be used in the present invention is a compound represented by the general formula %. In the formula, R+ is an alkali metal or an ammonium compound, Rs, Rs, Rs and R6
is hydrogen, halogen, alkyl group, or alkoxyl group, and R4 is hydrogen, halogen, 7) Lt-kyl group, amino group, benzoylamide 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,
Benzene azosulfonate having a substituent such as 2,4-dimethyl, 2,4゜6-trimethyl, 4-phenyl, 4-phenoxy, 4-acetamide, etc., or 4-(N-ethyl-N-benzyl amino), 4-(N,
N-dimethylamino), 4-(N,N-diethylamino)-3-chlor, 4-pyrogeno-3-chlor, 4-morpholino-2-methoxy, 4-(4°-methoxybenzylbenzoylamino)-2, 5-dibutoxy, 4-(
It is a benzenesulfonate having a substituent such as 4'-mercapto)-2,5-dimethoxy. When using these diazosulfonate compounds, it is desirable to irradiate the diazosulfonate with light to activate the diazosulfonate before printing.

Moreover, diazoamino compounds can be mentioned as other diazo compounds that can be used in the present invention. The diazoamino compound is a compound obtained by coupling a diazonium salt with dicyandiamide, sarcosine, methyltaurine, N-ethylanthranic acid-5-sulfonine quacid, monoethanolamine, jetanolamine, guanidine, or the like.

The color developer for the diazo compound used in the present invention is a coupling component that couples with the diazo compound (diazonium salt) to form a dye.

As a specific example, for example, 2-hydroxy-3-
In addition to naphthoic acid anilide, there may be mentioned those described in Japanese Patent Application No. 60-287485, including resorcinol.

Furthermore, by using two or more of these coupling components in combination, an image of any color tone can be obtained. Since the coupling reaction between these diazo compounds and the coupling component is likely to occur in a basic atmosphere, a basic substance may be added to the layer.

As the basic substance, a poorly water-soluble or water-insoluble basic substance or a substance that generates an alkali upon heating is used. Examples of these are inorganic and organic ammonium salts,
Organic amines, amides, urea and thiourea and their derivatives, thiazoles, pyrroles, pyrimidines, piperazines, guanidines, indoles, imidazoles,
Examples include nitrogen-containing compounds such as imidacillins, triazoles, morpholines, piperidines, amidines, formazines, and pyridines. Specific examples of these are described, for example, in Japanese Patent Application No. 60-132990.

Two or more types of basic substances may be used in combination.

The hue in this coloring system is mainly determined by the diazo dye produced by the reaction between the diazo compound and the coupling component. Therefore, as is well known, the coloring hue can be easily changed by changing the chemical structure of the diazo compound or the chemical structure of the coupling component, and almost any coloring hue can be obtained depending on the combination. be able to. For this reason, one layer may contain various diazo compounds, and one type of coupling component or other additives may be incorporated into the same layer. In this case, each unit color forming group may contain a different diazo compound. It consists of the same coupling components and other additives. Also, there is a combination in which separate coupling components are contained in several layers and the same diazo and other additives are incorporated in each layer. At this time, each unit coloring group is composed of a different coupling component and a common diazo compound and additive. In any case, each unit color-forming group is composed of one or more diazo compounds combined to produce different color hues, one or more coupling components, and other additives.

The amount of coupling component per 1 part by weight of the diazo compound is 0.
It is preferable to use 1 to 10 parts by weight, and the basic substance to be used in a proportion of 0.1 to 20 parts by weight.

／ ／ ／ ／' ＼, Materials that produce the above color reaction are selected from the viewpoint of improving transparency, preserving stability by preventing contact between color former and color developer at room temperature (capri prevention), and desired printability. A part of the components can also be microencapsulated and used from the viewpoint of controlling color development sensitivity such as color development using energy.

The wall materials of the microcapsules mentioned above include polyurethane, polyurea, polyester, polycarbonate, urea-formaldehyde resin, melamine resin, polystyrene, styrene-methacrylate copolymer, styrene-acrylate copolymer, gelatin, polyvinylpyrrolidone,
Examples include polyvinyl alcohol. In the present invention, two or more of these polymeric substances can also be used in combination.

In the present invention, among the above-mentioned polymeric substances, polyurethane, polyurea, polyamide, polyester, polycarbonate, etc. are preferable, and polyurethane and polyurea are particularly preferable.

The microcapsules used in the present invention are preferably formed by emulsifying a core material containing a reactive substance such as a coloring agent, and then forming a wall of a polymer material around the oil droplets to form microcapsules. In this case, a reactant forming a polymeric substance is added inside the oil droplet and/or outside the oil droplet. Details of microcapsules that can be preferably used in the present invention, such as a preferred method for producing microcapsules, are described in, for example, JP-A-60-242094.

Here, the organic solvent for forming oil droplets can generally be appropriately selected from high boiling point oils, but
In particular, compounds having the following general formulas (1) to
The compound represented by (III) and triallylmethane (
For example, tritolylmethane, tolyldiphenylmethane), terphenyl compounds (e.g. terphenyl)
, alkylated diphenyl ether (e.g., propyl diphenyl ether), hydrogenated terphenyl (e.g., hexahydroterphenyl), diphenyl ether, etc., increase the color density and color development speed during thermal printing, and This is preferable because it can also reduce fog.

In the formula, R1 is hydrogen or an alkyl group having 1 to 1 carbon atoms,
R1 represents an alkyl group having 1 to 18 carbon atoms, p', q
' represents an integer from 1 to 4, and the total number of alkyl groups is 4 or less.

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

(II) (R')p''(R')q'' In the formula, R8 is a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R4 is an alkyl group having 1 to 12 carbon atoms, and n represents 1 or 2. .

p! , q X represents an integer from 1 to 4. When n-1, the total number of alkyl groups is 4 or less, and when n-2, the total number of alkyl groups is 6 or less.

(III) In the formula, R5 and Rh represent a hydrogen atom or a same or different alkyl group having 1 to 18 carbon atoms.

m represents an integer from 1 to 13; q' represents an integer from 1 to 3;
represents an integer, and the total number of alkyl groups is 3 or less.

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

Examples of the compound represented by formula (1) include dimethylnaphthalene, diethylnaphthalene, and diisopropylnaphthalene.

Examples of the compound represented by formula [■] include dimethylbiphenyl, diethylbiphenyl, diisopropylbiphenyl, and diisobutylbiphenyl.

Examples of the compound represented by formula (III) include l-methyl-1-dimethylphenyl-1-phenylmethane, l-
ethyl-1-dimethylphenyl-1-phenylmethane,
l-Propyl-1-dimethylphenyl-1-phenylmethane is an example.

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, benzoate ester (ethyl benzoate, propyl benzoate, butyl benzoate, isopentyl benzoate, benzyl benzoate),
Abietate ester (ethyl abietate, benzyl abietate), dioctyl adipate, isodecyl succinate, dioctyl azelaate, oxalate ester (
dibutyl oxalate, dipentyl oxalate), diethyl malonate, maleate esters (dimethyl maleate, diethyl maleate, dibutyl maleate), tributyl citrate, sorbate esters (methyl sorbate, ethyl sorbate, butyl sorbate) , sebacate ester (dibutyl sebacate, dioctyl sebacate),
Ethylene glycol esters (formic acid monoesters and diesters, butyric acid monoesters and diesters, lauric acid monoesters and diesters, palmitic 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.

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

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

In the present invention, it is also possible to use a color development aid.

The color development aid that can be used in the present invention is a substance that increases the color density during thermal printing or lowers the minimum color development temperature, and lowers the melting point of the coupling component, basic substance, or diazo compound layer. This is to create a situation where the diazo, basic substance, and coupling component are more likely to react by lowering the softening point of the capsule wall.

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

The color-forming 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/m'' in terms of solid content.

In the present invention, it is essential to provide an intermediate layer between the coloring layers, but in the present invention, as this intermediate layer,
In particular, a layer formed by gelling a water-soluble polyanionic polymer with polyvalent cations is used.

Preferred water-soluble polyanionic polymers are those having carboxyl groups, sulfonic acid groups, and phosphoric acid groups, and particularly preferred are water-soluble polyanionic polymers having carboxyl groups. Examples of preferred water-soluble polyanionic polymers include natural or synthetic polyanionic polymers. Many 1! ! Gums (
Examples include alginate alkali metal salts, guar gum,
gum arabic, carrageenan, pectin, gum tragacanth, xanthine gum, etc.), polymers of acrylic acid or methacrylic acid and their copolymers, polymers of maleic acid or phthalic acid and their copolymers, cellulose derivatives such as carboxymethyl cellulose, gelatin , agar, etc., among which alginate alkali metal salts are preferred. The molecular weight of the water-soluble polyanionic polymer 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 40,0
00 is preferred. Examples of polyvalent cations include salts of alkaline earth metals and other polyvalent metals (for example, CaCj!z, Ba
C1t, Alt<5o4)s, Zn5Oi, etc.), polyamine 111 (for example, ethylenediamine, diethylenetriamine, hexamethylenediamine, etc.), and polyimines are preferable.

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, it is important to avoid using one material first 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
t, more preferably 0.1 g/m2 to 2 g/m
” is.

In the present invention, a white pigment may be added to the coloring layer or intermediate layer for the purpose of preventing fog or increasing whiteness, or a layer containing a white pigment may be additionally coated.

Examples of preferred white pigments include talc, calcium carbonate, calcium sulfate, magnesium carbonate, magnesium hydroxide, alumina, synthetic silica, titanium oxide, barium sulfate, kaolin, calcium silicate, urea resin, and the like.

Furthermore, it is also possible to provide a protective layer on the top layer.

The adhesive used includes water-soluble polymers such as polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, methylcellulose, ethylcellulose, carboxymethylcellulose, and hydroxyethylcellulose to which pigments, metal soaps, wax, crosslinking agents, etc. are added.

Pigments include zinc oxide, calcium carbonate, barium sulfate, titanium oxide, lithopone, talc, Rouseki, kaolin, aluminum hydroxide, amorphous silica, etc., and the amount added is 0.05 to 2.0% of the total weight of the polymer. times, particularly preferably 0
．． It is 1 to 5 times the amount.

Metal soaps include emulsions of metal salts of lighter fatty acids such as zinc stearate, calcium stearate, and aluminum stearate, and contain 871 in an amount of 0.5 to 20% by weight, preferably 1 to 10% by weight of the total weight of the protective layer. added in the same amount. Waxes include emulsions such as paraffin wax, microcrystalline wax, carnauba wax, methylolstearamide, polyethylene wax, and silicone, and their content is 0.5 to 40% by weight of the total weight of the protective layer.
, preferably in a proportion of 1 to 20% by weight.

Furthermore, a surfactant, a polymer electrolyte, etc. may be added to the protective layer to prevent charging of the heat-sensitive recording material. The solid coating amount of the protective layer is usually preferably 0.2 to 5 g/rrf, more preferably 1 g to 3 g/rrf.

Details regarding the safety layer are described in Paper Valve Technology Times No. 8 (1985).

Furthermore, an undercoat layer may be provided for the purpose of increasing the adhesion between the support and the coloring layer, improving smoothness, and providing heat insulation.

As the material for the undercoat layer, water-soluble polymers such as gelatin, synthetic polymer latex, nitrocellulose, etc. are used. The coating amount of the undercoat layer is 0.1g/r+ (~2.Og/rd
It is preferably in the range of 0.2g/m-1, particularly 0.2g/m-1,
A range of 0 g/rrr is preferred.

Examples of the support used in the present invention include paper, synthetic paper, and polymer film.

In the present invention, the paper used for the support is a neutral paper with a heat extraction pH of 6 to 9 resized with a neutral sizing agent such as an alkyl ketene dimer (Japanese Patent Application Laid-Open No. 55-1428
The use of the product described in No. 1) is advantageous in terms of storage stability over time.

In order to prevent the coating liquid from penetrating into paper,
The paper described in No. 687 and having a Bekk smoothness of 90 seconds or more is advantageous.

In addition, paper having an optical surface roughness of 8μ or less and a thickness of 40 to 75μ described in JP-A-58-136492, JP-A-58-136492,
Paper with a density of 0°9g/c+j or less and an optical contact ratio of 15% or more described in JP-A No. 8-69097, JP-A-58-690
Canadian Standard Freeness as described in No. 97 (JTS P812
Paper made from pulp beaten to 400 cc or more in 1) to prevent penetration of coating liquid, JP-A-58-6569
5, the glossy side of base paper made by a Yankee machine is used as the coated surface to improve color density and resolution, and JP-A No. 59-35985 describes a method in which the base paper is subjected to corona discharge treatment. Papers with improved coating suitability may 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.

In the present invention, a back layer may be provided on the back surface of the support for the purpose of curl correction, antistatic properties, and improved slipperiness.As the constituent components of the back layer, it is preferable to use the same components as those of the protective layer. .

Among the supports used in the present invention, polymer films include polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate films, polystyrene films, polypropylene films, and polyolefin films such as polyethylene. , these can be used alone or in combination.

The thickness of the support used is 20 to 200 .mu.m, particularly preferably 50 to 100 .mu.m.

The coating liquid according to the present invention is prepared by -a (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 bar code 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 the coating simultaneously in two or more layers using the method described in page 3 (published by Asakura Shoten in 1973), etc., and it is possible to select an appropriate method depending on the amount of coating, coating speed, etc. can.

Adding pigment dispersants, thickeners, flow modifiers, antifoaming agents, foam inhibitors, mold release agents, colorants, surfactants, etc. to the coating liquid used in the present invention can be carried out as necessary. There is nothing wrong with it as long as it does not impair its characteristics.

When carrying out the present invention, the number of coloring layers is not limited to two, and a plurality of layers can be further provided thereon. In this case, coloring layers with different coloring hues are usually provided.

It is also possible to provide coloring layers on both sides of the support.

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

Note that "parts" indicating the amount added represent "parts by weight."

Example 1°, 10C, HQ! - Liclesyl phosphate 6 parts Methylene chloride 12 parts Trimethylolpropane triacrylate 18 parts Taken) D-11ON (75% ethyl acetate solution) (manufactured by Takeda Pharmaceutical Company Ltd. (trade name)) 24 parts were mixed, Polyvinyl alcohol (Kuraray PVA-217E) 8% by weight
After adding it to an aqueous solution consisting of 63 parts of aqueous solution and 100 parts of distilled water, it was emulsified and dispersed at 20°C to obtain an emulsion with an average particle size of 2μ, and the resulting emulsion was continuously stirred at 40°C for 3 hours. .

After cooling this liquid to 20°C, Amberlite IR-
120B (manufactured by Rohm and Haas (product name))
00 cc was added, stirred for 1 hour, and then filtered to obtain a capsule liquid.

Kaboo I-A i- ■, 170 parts of polyvinyl alcohol (Kuraray PVA205) 4% aqueous solution ■, coupler
14 parts (J
(J ■, triphenylguanidine (base) 6 parts ■1 color development aid mixed, Dynomil (Willy A Bacofen,
Dispersed with A.G. Co., Ltd. (trade name) to achieve an average particle size of 3.
A dispersion of μ was obtained.

Kaboo aba 2B i ■, polyvinyl alcohol (Kuraray PVA205) 4% aqueous solution 170 parts ■, coupler 2-hydroxy-3-naphthoic acid anilide (naphthol AS) 20 parts ■, triphenylguanidine (base) 6 parts ■ 1 Mix the color development aid and use Dynomil (Willy A. Bacofuen).
Dispersed with A.G. Co., Ltd. (trade name) to achieve an average particle size of 3.
A dispersion of μ was obtained.

m Adult q Preparation Silica-modified polyvinyl alcohol (PVA manufactured by Kuraray)
R2105) 10% by weight liquid 10 parts Colloidal silica (Snowtex 30 manufactured by Nissan Chemical ■) 300
Heavy lid liquid 5 parts Zinc stearate (Hydrin Z-7 manufactured by Middle East Yushi ■) 30% by weight liquid
Protective layer liquid A was obtained by mixing 0.42 parts of paraffin wax (Hydrin P~7 manufactured by Middle East Oil Co., Ltd.) and 0.42 parts of 300-gold liquid.

6 parts of Capsule Liquid A, 85 parts of coupler/base dispersion liquid on Keyaki with dry coating amount of 100/Po on high quality paper with γ1 basis weight of 50 g/Bo
．． After applying 5 parts of the mixed solution, a 3% aqueous solution of sodium alginate (Snow Algin SH manufactured by Fuji Kagaku ■) was applied as an intermediate layer so that the dry coating amount was 0.5 g/ni.

Next, 6 parts of capsule liquid A, coupler/base dispersion A
After applying a mixture of 5.5 parts and 0.5 parts of a 20% calcium chloride aqueous solution to a dry coating amount of 6 g/rrf,
Apply retaining liquid A so that the dry coating amount is 2g/bo,
I got a record sheet. The coating was done using a wire bar and then dried in an oven at 50°C.

The obtained recording sheet was thermally printed with low energy (thermal head voltage 15 V, printing time 0 to 2.5 m5ec),
A blue colored image was obtained. Next, thermal printing was performed at high energy (thermal head voltage 17 V, printing time 0 to 2.5 m5ec) to obtain a black colored image.

Next, after irradiating with light for 10 seconds using a Rifby Super Dry 100 model, a red color image was obtained by thermal printing with high energy (thermal head voltage: 17 V, printing time: 2.5 to 5 m5 ec). In this way, a clear colored image was obtained.

Further, even when this sheet was stored for a long time, there was no increase in fog or change in print density.

Comparative Example 1 A recording sheet was obtained in exactly the same manner as in Example 1, except that no intermediate layer was provided.

When the obtained sheet was colored in the same manner as in Example 1, red color mixture was observed in low energy printing, and only cloudy blue printing was possible.

Furthermore, even in high-energy printing after fixing, blue color mixture was observed and only cloudy red printing was obtained.

In addition, the above-mentioned color mixing became even worse in samples stored for a long period of time.

Claims (1)

[Claims] 1) In a multicolor recording material in which at least two color-forming layers containing a diazo compound and a coupler as color-forming components and each capable of developing colors of different hues are provided in a superimposed manner on one side of a support, the color-forming layer and A multicolor recording material characterized by providing an intermediate layer formed by gelling a water-soluble polyanionic polymer with polyvalent cations between the coloring layers.