JPH04334488A - Photosensitive thermal recording material - Google Patents

Abstract

PURPOSE:To provide photosensitive and thermosensitive recording material having excellent transparency and stick resistance for a thermal head. CONSTITUTION:A photosensitive and thermosensitive recording material is provided, on a support body in order, with a thermosensible layer containing at least photodissociative diazo compound and coupler separated by micro capsule wall, and with a protective layer. The thermosensitive layer is a transparent photosensitive and thermosensitive layer formed by coating liquid and drying it. The coating liquid includes micro capsule containing at least the diazo compound and the coupler respectively independently. Or, the coating liquid includes micro capsule containing either the diazo compound or the coupler and, as emulsified dispersed material, other diazo compound or coupler which are not capsuled. The protective layer contains fluorine polymer.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a photosensitive thermosensitive recording material that can be recorded using light or heat, and in particular has a transparent recording layer and is highly resistant to sticking when recorded with a thermal head. Regarding heat-sensitive recording materials.

0002

[Prior Art] Thermal recording methods are widely used in fields such as facsimiles and printers because they have advantages such as no development required, easy handling, simple and inexpensive recording devices, and low noise during recording. As a result, the need for heat-sensitive recording materials is also expanding.

[0003] Conventionally, OHP heat-sensitive recording materials include those based on a thermal copying method using a heat-reactive substance, those that distort a resin layer coated on a film by heat, and those that use thermal transfer using an ink sheet. things are known.

However, with any of these heat-sensitive recording materials, the color density is not sufficient when recording an image by heat recording, the image contrast is poor when the image is projected onto a screen by OHP, and it is difficult to transmit the image electronically by facsimile. There was a drawback in that it was not possible to directly thermally record the image clearly and use it for OHP.

The present inventors have already developed a microcapsule containing a diazo compound and an emulsion in which a coupler is dissolved in an organic solvent that is sparingly soluble or insoluble in water and then emulsified and dispersed as a heat-sensitive recording material capable of solving the above-mentioned drawbacks. A light and heat sensitive recording material was proposed in which a coating liquid containing a dispersion was coated on a support (Japanese Patent Application Laid-open No. 318546/1983).

[0006]

However, the photosensitive and thermosensitive recording materials described above have a drawback in that sticking occurs in the thermal head when thermal recording is performed (poor sticking resistance). As a result of intensive studies to solve the above-mentioned drawbacks, the present inventors found that good results can be obtained by providing a protective layer containing a fluorine-based polymer on the heat-sensitive layer of a light- and heat-sensitive recording material. The present inventors have discovered that even when the compound and the coupler are contained in separate microcapsules, a heat-sensitive recording layer with sufficiently excellent transparency can be obtained, and the storage stability is also significantly improved.

[0007] Accordingly, a first object of the present invention is to provide a photo- and heat-sensitive recording material which has a transparent recording layer and has excellent sticking resistance. A second object of the present invention is to provide a light- and heat-sensitive recording material having a transparent recording layer, which has not only excellent sticking resistance but also particularly excellent storage stability before recording.

[0008]

[Means for Solving the Problems] The above-mentioned objects of the present invention are to provide, in sequence, on a support, at least a heat-sensitive layer containing a photodegradable diazo compound and a coupler separated by a microcapsule wall, and a protective layer. A light- and heat-sensitive recording material comprising a coating liquid containing at least microcapsules each independently encapsulating a diazo compound and a coupler, or microcapsules and microcapsules containing either the diazo compound or the coupler. A transparent photosensitive and heat-sensitive layer formed by coating and drying a coating solution containing the other non-encapsulated diazo compound or coupler as an emulsified dispersion, and the protective layer containing a fluorine-based polymer. This was achieved by a light- and heat-sensitive recording material characterized by a protective layer consisting of:

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 includes aromatic diazo compounds, etc. refers to aromatic diazonium salts, diazosulfonate compounds, and diazoamino compounds. Hereinafter, explanation will be given mainly using diazonium salts as examples.

It is generally said that the photodecomposition wavelength of a diazonium salt is its maximum absorption wavelength. It is also known that the maximum absorption wavelength of diazonium salts varies from about 200 nm to about 700 nm, depending on its chemical structure. (“Photodecomposition and chemical structure of photosensitive diazonium salts” by Takahiro Tsunoda and Ao Yamaoka, Journal of the Photographic Society of Japan 29(4) 19
pp. 7-205 (1965).

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 heat recording. Furthermore, by changing the chemical structure, the hue of the dye after the reaction can be changed even when the same coupling component is used for the coupling reaction.

Diazonium salts have the general formula ArN2 +
It is a compound represented by X- (wherein Ar represents a substituted or unsubstituted aromatic moiety, N2 + represents a diazonium group, and X- represents an acid 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. Diazo-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-diethoxybenzene, 4-diazo-1-morpholinobenzene, 4- Diazo-1-morpholino-2,5-diethoxybenzene, 4-
Diazo-1-morpholino-2,5-dibutoxybenzene, 4-diazo-1-anilinobenzene, 4-diazo-1
-Toluylmercapto-2,5-diethoxybenzene,
4-diazo-1,4-methoxybenzoylamino-2,
Examples include 5-diethoxybenzene.

Compounds having a photolysis wavelength of 300 to 370 nm include 1-diazo-4-(N,N-dioctylcarbamoyl)benzene, 1-diazo-2-octadecyloxybenzene, 1-diazo-4-(4 ─tert
-octylphenoxy)benzene, 1-diazo-4-(
2,4-di-tert-amylphenoxy)benzene,
1-Diazo-2-(4-tert-octylphenoxy)benzene, 1-diazo-5-chloro-2-(4-te
rt-octylphenoxy)benzene, 1-diazo-2
, 5-bis-octadecyloxybenzene, 1-diazo-2,4-bis-octadecyloxybenzene, 1-diazo-4-(N-octylteuroylamino)benzene, and the like. The photolysis wavelength of the aromatic diazonium compounds typified by the examples listed above can be varied widely by arbitrarily changing the substituents.

Specific examples of acid anions include Cn F2
n+1COO- (n represents 3 to 9), Cm F2
m+1SO3 − (m represents 2 to 8), (Cl
F2l+1SO2)2CH- (l represents 1 to 18),

[Chemical formula 1]

[Case 2]

[Chemical formula 3]

[C4]

[C5]

[C6] and PF6-, etc.

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

[C7]

[Chemical formula 8]

[Chemical formula 9]

[Chemical formula 10]

[Chemical formula 11]

[Chemical formula 12]

[Chemical formula 13]

[Chemical formula 14]

[Chemical formula 15]

The diazosulfonate compound used in the present invention has the general formula (Chemical formula 16)

This is a compound represented by the following formula. In the formula, R1 is an alkali metal or ammonium compound, R2, R3, R5 and R6 are hydrogen, halogen, alkyl group, or alkoxy group, and R4 is hydrogen, halogen, alkyl group, amino group, benzoylamido group, or 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. Among these compounds, preferred compounds include 2-methoxy, 2-phenoxy, 2-methoxy-4-phenoxy, 2,4-dimethoxy, 2-methyl-4-methoxy, 2,4-dimethyl, 2,
4,6-trimethyl, 4-phenyl, 4-phenoxy,
Benzenediazosulfonate having a substituent such as 4-acetamide, or 4-(N-ethyl, N-benzylamino), 4-(N,N-dimethylamino), 4-(
N,N-diethylamino), 4-(N,N-diethylamino)-3-chlor, 4-pyrodinino-3-chlor, 4
-morpholino-2-methoxy, 4-(4'-methoxybenzoylamino)-2,5-dibutoxy, 4-(4'-
It is a benzenediazosulfonate having a substituent such as trimercapto-2,5-dimethoxy. When using these diazosulfonate compounds, it is desirable to irradiate the diazosulfonate with light to activate the diazosulfonate before printing.

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, diethanolamine, guanidine, etc.

The coupler used in the present invention forms a dye by coupling with a diazo compound (diazonium salt), and specific examples include resorcinol, phloroglucin, and sodium 2,3-hydroxynaphthalene-6-sulfonate. , 1-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-dodecyloxy-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-
Examples include (2',4',6'-trichlorophenyl)-3-anilino-5-pyrazolone and 1-phenyl-3-phenylacetamido-5-pyrazolone. Furthermore, by using two or more of these coupling components in combination, an image of any color tone can be obtained.

It is preferable to add a basic substance to the recording layer of the photosensitive and thermosensitive recording material of the present invention, if necessary, for the purpose of making the system basic and promoting the coupling reaction. 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, thiazoles, pyrroles, pyrimidines, piperazines, guanidines, indoles, imidazoles, imidazolines, triazoles, morpholines, piperidines, amidines, formazines,
Examples include nitrogen-containing compounds such as pyridines. Two or more of these basic substances can be used in combination.

The light and heat sensitive recording material of the present invention contains a hydroxy compound, a carbamate ester compound, an aromatic methoxy compound or an organic sulfonamide compound in the light and heat sensitive layer so that thermal development can be carried out quickly and completely with low energy. It can be added as a thermal color sensitizer. It is believed that these compounds lower the melting point of the coupling component or basic substance or improve the thermal permeability of the microcapsule wall, thereby increasing the practical concentration.

[0024] In the present invention, from the viewpoint of shelf life (preventing fogging) by preventing contact between the diazo compound and the coupler at room temperature, and from the viewpoint of controlling color development sensitivity so that color is developed with the desired applied heating energy, etc. Either the diazo compound or the coupler, or the diazo compound and the coupler are each independently microencapsulated for use.

Particularly preferred microcapsules in this case are those that prevent contact between substances inside and outside the capsule due to the substance isolation effect of the microcapsule wall at room temperature, and that permeability of substances increases only when heated above a certain temperature. By appropriately selecting capsule wall materials, capsule core materials, 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, in
9-91438 etc.).

[0026] 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. . 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 preferred, and polyurethane and polyurea are particularly preferred.

The microcapsules used in the present invention are preferably microencapsulated by emulsifying a core material containing a diazo compound or a coupler, and then forming a wall of a polymer material around the oil droplets. In this case, a reactant forming a polymeric substance is added to the interior of the oil droplet and/or to the exterior of the oil droplet. For details about microcapsules that can be preferably used in the present invention, such as a preferred method for producing microcapsules, see, for example, JP-A-59-22271.
It is stated in No. 6.

[0029] 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 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 can permeate through the microcapsule wall and react upon heating. The amount of coupling component is 0.0% per 1 part by weight of the diazo compound.
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.

[0031] 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 heat color development or lowers the minimum color development temperature, and lowers the melting point of coupling components, basic substances, or diazo compounds, etc. This is to create a situation where diazo, basic substances, coupling components, etc. can easily 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, phenyl p-oxybenzoate, Benzyl carbanylate, phenethyl carbanylate, hydroquinone dihydroxyethyl ether, xylylene diol, N-hydroxyethyl-
Compounds such as methanesulfonic acid amide and N-phenyl-methanesulfonic acid amide can be mentioned. These may be contained in the core material or may be added outside the microcapsules as an emulsified dispersion.

In the present invention, in order to obtain a substantially transparent photosensitive and thermosensitive layer, the diazo compound and the coupler are microencapsulated independently, or when only one of them is microencapsulated, the other is microencapsulated. After dissolving it in an organic solvent that is sparingly soluble or insoluble in water, it is mixed with an aqueous phase containing a surfactant and a water-soluble polymer as a protective colloid, and used in the form of an emulsified dispersion.

The organic solvent used in this case can be appropriately selected from high boiling point oils. In addition to esters, preferred oils include the following (Chemical formula 17):
Compounds represented by ~(Chemical formula 19) and triallylmethane (e.g. tritolylmethane, tolyldiphenylmethane), terphenyl compounds (e.g. terphenyl)
, alkyl compounds (eg, terphenyl), alkylated diphenyl ethers (eg, propyl diphenyl ether), hydrogenated terphenyl (eg, hexahydroterphenyl), diphenyl ether, and the like. In the present invention, it is preferable to use esters among these from the viewpoint of emulsion stability of the emulsified dispersion.

[0035]

embedded image In the formula, R1 is hydrogen or an alkyl group having 1 to 18 carbon atoms,
R2 represents an alkyl group having 1 to 18 carbon atoms. p1
, q1 represents an integer of 1 to 4, and the total number of alkyl groups is 4 or less. In addition, the alkyl group of R1 and R2 is preferably an alkyl group having 1 to 8 carbon atoms.

[0036]

embedded image 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
represents 1 or 2. p2 and q2 represent integers 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.

[0037]

embedded image In the formula, R5 and R6 are hydrogen atoms or have 1 to 18 carbon atoms
represents the same or different alkyl groups. m is 1-1
Represents an integer of 3. p3 and q3 represent integers of 1 to 3, and the total number of alkyl groups is 3 or less. In addition, R
The alkyl group represented by 5 and R6 is particularly preferably an alkyl group having 2 to 4 carbon atoms.

Examples of the compound represented by (Chemical formula 17) are:
Examples include dimethylnaphthalene, diethylnaphthalene, diisopropylnaphthalene, and the like. Examples of the compound represented by (Chemical formula 18) include dimethylbiphenyl, diethylbiphenyl, diisopropylbiphenyl, and diisobutylbiphenyl. Examples of compounds represented by (Chemical formula 19) include 1-methyl-
1-dimethylphenyl-1-phenylmethane, 1-ethyl-1-dimethylphenyl-1-phenylmethane, 1-
Propyl-1-dimethylphenyl-1-phenylmethane is mentioned.

Examples of esters include phosphate esters (for example, triphenyl phosphate, tricresyl phosphate, butyl phosphate, octyl phosphate, cresyl diphenyl phosphate), phthalate esters (dibutyl phthalate, 2-ethylhexyl phthalate, phthalate). Ethyl, octyl phthalate, butyl benzyl phthalate) dioctyl tetrahydrophthalate,
Benzoate esters (ethyl benzoate, propyl benzoate, butyl benzoate, isopentyl benzoate, benzyl benzoate), abietate esters (ethyl abietate, benzyl abietate), dioctyl adipate, isodecyl succinate, dioctyl azelate, Oxalate esters (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 esters (dibutyl sebacate, dioctyl sebacate), ethylene glycol esters (formate monoesters and diesters, butyrate 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, tripentyl borate), etc.

Among these, it is preferable to use tricresyl phosphate alone or in combination because the emulsion dispersion stability of the diazo or coupler is particularly good. 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 solubilizing agent. Particularly preferred examples of such co-solvents include ethyl acetate, isopropyl acetate, butyl acetate and methylene chloride.

In the present invention, in order to stabilize the emulsified dispersion of the coupler, a phenolic compound and a salicylic acid derivative metal salt may be co-dissolved together with the coupler in the organic solvent.

[0043] The phenolic compound used in the present invention is
Particularly preferred are those with a melting point of 50°C to 250°C, especially 6
A phenolic compound that is sparingly soluble in water at a temperature of 0°C to 200°C is preferred. Particularly preferable phenolic compounds are represented by the following general formulas (Formula 20) to (Formula 24).

[0044]

[C20] m=0-2, n=2-11

embedded image R1 is an alkyl group, an aryl group or an aralkyl group, and methyl, ethyl and butyl groups are particularly preferred.

[0045]

embedded image R2 is an alkyl group, particularly preferably a butyl group, a pentyl group, a heptyl group, and an octyl group. R3 is a hydrogen atom or a methyl group, and n is 0-2.

[C23] R4 is an alkyl group or an aralkyl group.

embedded image R5 and R6 are hydrogen, halogen, hydroxyl group,
Represents a nitro group, an alkyl group, an allyl group, an aralyl group, and an alkylaryl group.

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

[0047] As the surfactant to be contained in the aqueous phase, a surfactant that does not cause precipitation or aggregation by interacting with the above-mentioned protective colloid should be appropriately selected from anionic or nonionic surfactants. Can be done.

Preferred surfactants include sodium alkylbenzenesulfonate, sodium alkylsulfate, dioctyl sodium sulfosuccinate, polyalkylene glycol (eg, polyoxyethylene nonylphenyl ether), and the like.

[0049] The emulsified dispersion in the present invention is produced by combining 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 mixed and dispersed easily.

[0050] The oil droplet size (diameter) of this emulsified dispersion is:
In order to obtain a substantially transparent light and heat sensitive layer with a haze of 60% or less, it is preferably 7 μm or less. More preferably, it is within the range of 0.1 to 5 μm.

The ratio of the oil phase to the aqueous phase (oil phase weight/aqueous phase weight) is preferably from 0.02 to 0.6. More preferably, it is 0.1 to 0.4. If it is less than 0.02, there will be too much water phase and it will be diluted and sufficient color development will not be obtained;
On the contrary, the viscosity of the liquid increases, resulting in inconvenience in handling and a decrease in stability of the coating liquid.

The heat-sensitive material of the present invention can be coated using a suitable binder. As a binder, polyvinyl alcohol, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, gum arabic, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylic acid ester, ethylene-vinyl acetate copolymer Various emulsions such as can be used. The amount used is 0.5 to 5 g/m2 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 background part can be viewed from one side of the transparent support. If the back side of the transparent support is visible, the image will not be clear, 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, magnesium hydroxide, alumina, synthetic silica, titanium oxide, barium sulfate, kaolin, calcium silicate, urea resin, and the like.

[0054] The coating amount of the photosensitive and thermosensitive layer is 3 g/m2 to 20
g/m2, especially between 5 g/m2 and 15 g/m2. If it is less than 3 g/m 2 , sufficient sensitivity cannot be obtained, and even if it is applied more than 20 g/m 2 , no improvement in quality is observed, which is disadvantageous in terms of cost. It is also possible to provide a multicolor recording material by providing heat-sensitive layers that develop colors in different hues in an overlapping manner and/or in combination with a heat-sensitive layer having another color-developing system such as a leuco system.

In order to improve the scratch resistance and solvent resistance of the light and heat sensitive recording material of the present invention and to ensure the transparency of the light and heat sensitive layer and the stigma resistance against thermal heads, a transparent protective layer is provided on the light and heat sensitive layer. It is preferable to provide one.

Transparency of the photosensitive and thermosensitive layer of the present invention means haze (
%) (measured with an integrating sphere HTR meter manufactured by Nippon Seimitsu Kogyo Co., Ltd.) is 60% or less, preferably 4
It is 0% 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 described above, the protective layer provided on the photosensitive and thermosensitive layer is preferably made of silicon-modified polyvinyl alcohol and colloidal silica because of its 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-58-193189.
It is listed in the issue announcement.

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 colloidal silica is 10 mμ to 100 mμ, and the specific gravity is 1.1 to 1.
3 is preferred. In this case, the colloidal solution preferably has a pH value of about 4 to about 10.

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 high. The transparency of the light- and heat-sensitive recording material as a whole can be further improved significantly.

Furthermore, when this protective layer is provided as the outermost layer of the recording material, the mechanical strength of the surface of the photosensitive and thermosensitive layer is improved, and when it is provided as an intermediate layer between laminated layers, unnecessary interlayer It can additionally play the role of preventing color mixing.

A suitable blending ratio of the silicon-modified polyvinyl alcohol and colloidal silica is 0 parts by weight of colloidal silica to 1 part by weight of silicon-modified polyvinyl alcohol.
．． The amount is 5 to 3 parts by weight, more preferably 1 to 2 parts by weight. 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.

[0062] The above protective layer can be laminated in one or more layers. In the present invention, a fluoropolymer is contained in at least the uppermost protective layer in order to improve the sticking resistance against the thermal head.

The fluoropolymer used in the present invention can be appropriately selected from conventionally known ones. For example, such a fluorine-based polymer has 3 carbon atoms.
In addition to homopolymers or copolymers of unsaturated esters represented by acrylates or methacrylates containing ~20 perfluoroalkyl groups, CF2Cl (CF
3) CF(CF2)7 CONHCOOCH=CH
2, H(CF2)10CH2 OCOCH=CH2
and the following (chemical formula 25)

Examples include polymers or copolymers of polyfluoroalkyl group-containing compounds such as the following, and those containing perfluoroalkyl groups are particularly preferred.

Furthermore, considering the availability and other factors, the general formula RfROCOCR'=CH2 (wherein Rf is a linear or branched perfluoroalkyl group having 3 to 20 carbon atoms, and R is 1 A homopolymer of acrylate or methacrylate containing a terminal perfluoroalkyl group represented by a linear or branched alkylene group having ~10 carbon atoms, R' represents a hydrogen atom or a methyl group, or Copolymers are particularly preferred. Rf has 6 carbon atoms
~12 alkylene groups, R has 2 to 4 carbon atoms
Particularly preferred are alkylene groups.

Generally, in addition to the polyfluoroalkyl group-containing compounds, ethylene, vinyl acetate, vinyl chloride, vinyl fluoride, vinylidene halide, acrylonitrile,
methacrylonitrile, styrene, α-methylstyrene,
p-methylstyrene, acrylic acid and its alkyl esters, methacrylic acid and its alkyl esters, acrylamide, methacrylamide, diacetone acrylamide,
One or two compounds containing no fluoroalkyl group, such as methylolated diacetone acrylamide, N-methylol acrylamide, vinyl alkyl ether, halogenated alkyl vinyl ether, vinyl alkyl ketone, butadiene, isoprene, chloroprene, glycidyl acrylate, maleic anhydride. A copolymer of more than one species as a constituent unit can be used.

These fluorine-based polymers can be added not only to the components of the protective layer, but also to, for example, Asahi Guard, AG-550 (all trade names manufactured by Asahi Glass Co., Ltd.), Scotchban, FC808 ( All are product names manufactured by 3M Corporation in the United States), F-60 (trade names manufactured by Dainippon Ink Co., Ltd.), Polyflon, Neoflon, Daifree ME
It can also be used as an emulsion of a fluoropolymer such as 413 (all product names manufactured by Daikin Industries, Ltd.).

The amount of the fluoropolymer to be used is 1 to 60% by weight in the protective layer components, and particularly 20 to 60% by weight from the viewpoint of balance between transparency, water resistance, solvent resistance, and anti-sticking.
The content is preferably 40% by weight.

Sticking can be improved by using pigments such as silica, barium sulfate, titanium oxide, aluminum hydroxide, zinc oxide, calcium carbonate, styrene beads,
It can be made even more complete by adding fine powders such as urea-melamine resin. Similarly, waxes or metal soaps may be added to prevent sticking. The amount of these added is 0.2 to 7 (g/m2
).

In the present invention, on a known protective layer,
A fluoropolymer-containing protective layer according to the present invention may be laminated. Details of the above-mentioned known protective layer are described, for example, in "Paper and Pulp Technology Times" (September issue, 1985), pages 2 to 4. If necessary, a layer having the same composition as the protective layer may be provided as a back layer on the back surface of the support for the purpose of preventing curling of the heat-sensitive recording material or improving writing properties on the back surface.

In the present invention, in order to allow the heat-sensitive recording material to be conveyed smoothly within the recording apparatus, the protective layer and/or the back layer provided as necessary contain, together with a known antistatic agent, Or instead, the following general formula (1
) or (2) may be added.

General formula (1): R10O(CH2 CH2 O)m -H General formula (2)
: R20O(CH2)n-SO3M where R10
represents an alkyl group having 5 to 20 carbon atoms, R20 represents an aryl group having 6 to 30 carbon atoms, M represents an alkali metal or ammonium group, and m and n each represent an integer of 1 to 20.

The support used in the present invention may be transparent or opaque, but when it is used as an OHP heat-sensitive recording material, a transparent support is used, and when it is used as a negative-type heat-sensitive recording material, a transparent support is used. Use an opaque support. The transparent support preferably has high transparency and dimensional stability without being deformed even when heated during thermal recording. The thickness of the support used is 10 μm to 200 μm.

Examples of such transparent supports include:
Polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate films, polyolefin films such as polystyrene films, polypropylene films, and polyethylene films, polyimide films, polyvinyl chloride films, polyvinylidene chloride films,
Examples include polyacrylic film and polycarbonate film, and these can be used alone or in combination.

[0074] In order to prevent the whole heat-sensitive layer from peeling off from the support, it is desirable to provide an undercoat layer on the support before applying the heat-sensitive layer liquid containing microcapsules or the like onto the support. As the undercoat layer, acrylic ester copolymer, polyvinylidene chloride, SBR, water-based polyester, etc. can be used, and the film thickness is 0.1 to
0.5 μm is desirable. The coating amount is preferably 1 to 20 g/m2, particularly preferably 3 to 10 g/m2.

[0075] The undercoat layer is coated with a hardening agent because the image quality of the heat-sensitive layer may deteriorate if the undercoat layer swells due to water contained in the heat-sensitive layer when the heat-sensitive layer is coated thereon. It is desirable to harden using. Such hardeners are described in detail in JP-A-2-111585.

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, US Pat. No. 2,715,075, US Pat.
No. 846,727, No. 3,549,406, No. 3
, 590, 107, etc., is most preferably used.

On the other hand, examples of the opaque support for the recording material include paper, synthetic paper, an aluminum vapor-deposited base, and the transparent support coated with a pigment or the like. The paper used for the support is a heat-extracted neutral paper with a pH of 6 to 9 sized with a neutral sizing agent such as an alkyl ketene dimer (
The method described in JP-A-55-14281) is advantageous in terms of storage stability over time.

[0078] In order to prevent the coating liquid from penetrating the paper and improve the contact between the thermal recording head and the thermal recording layer, Japanese Patent Application Laid-Open No. 1983-
116687, (Steckicht size degree)/(meter weighing)2
≧3×10 −3 and a Bekk smoothness of 90 seconds or more is advantageous.

[0079] Also, as described in JP-A-58-136492, the optical surface roughness is 8 μm or less and the thickness is 40 to 75 μm.
m paper, density 0.9 g as described in JP-A No. 58-69097
/cm3 or less and paper with an optical contact ratio of 15% or more,
The Canadian standard freeness described in JP-A-58-69097 (
Paper made from pulp that has been beaten to 400 ml or more according to JIS P8121) and prevents coating liquid from seeping in.
JP-A No. 58-65695 discloses a method in which the glossy side of a base paper made by a Yankee machine is used as the coating surface to improve color density and resolution, and JP-A No. 59-35985 discloses a method in which corona is applied to base paper. Papers etc. which have been subjected to electrical discharge treatment to improve their suitability for application may also be used in the present invention and give 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.

[0080]

Effects of the Invention As detailed above, the light and heat sensitive recording material of the present invention contains a fluorine-based polymer in the protective layer, so it has extremely good sticking resistance without impairing the transparency of the light and heat sensitive layer. be.

[0081]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto. Note that "parts" indicating the amount added represent "parts by weight."

Example 1. Preparation of capsule liquid A Compounds below (Table 1)

[Table 1] ──────────────────────────
────────── Diazo compound of (Chemical formula 26)

3.4 parts

[Chemical formula 26] Tricresyl phosphate

6 parts methylene chloride

12 parts trimethylolpropane trimethacrylate
Part 18 Takenate D-110
N (75% by weight ethyl acetate solution)
24 parts (manufactured by Takeda Pharmaceutical Co., Ltd. (product name))──────────────────
────────────────────

After mixing and adding to an aqueous solution consisting of 63 parts of an 8% by weight aqueous solution of polyvinyl alcohol and 100 parts of distilled water, 20
The mixture was emulsified and dispersed at ℃ to obtain an emulsion having an average particle size of 2μ. next,
The obtained emulsion was stirred at 40°C for 3 hours. After cooling this liquid to 20°C, Amberlite IR-120B (
100 cc of Rohm and Haas Co., Ltd. (trade name) was added thereto, stirred for 1 hour, and then filtered to obtain capsule liquid A.

Preparation of coupler/base dispersion A (emulsified dispersion) Solution 1: 170 parts of a 4% by weight aqueous solution of polyvinyl alcohol. Solution 2:

[Table 2] ──────────────────────────
──────────(Chem.27) coupler

14 parts

[Chemical formula 27] Triphenylguanidine (base)

Compound represented by Part 6 (Chemical formula 28)

1.4 parts

[Chemical formula 28] Tricresyl phosphate

10 parts ethyl acetate

Part 20──────────
──────────────────────────
- Solution 2 was added to solution 1, mixed, and emulsified at 20°C to obtain an emulsified dispersion having an average particle size of 3 μm.

Preparation of coating solution A

[Table 3] ──────────────────────────
──────────Capsule liquid A

4.9 parts Hydroquinone 5% by weight aqueous solution
0.2 parts coupler/base dispersion A
3.
Part 7────────────────────────
──────────── were stirred and mixed to obtain coating liquid A.

Coating of recording sheet Coating solution A was applied onto a 75 μm transparent polyethylene terephthalate film and dried to give a dry weight of 12 g/m2.
A photosensitive and thermosensitive layer is formed, and then the following (Table 4)
A protective layer coating solution having the composition shown in the following was applied and dried to form a protective layer having a dry weight of 2 g/m<2 >to obtain the light and heat sensitive recording material of Example 1.

[0087]

[Table 4] ──────────────────────────
────────── [Protective layer composition] Silica-modified polyvinyl alcohol (R2105 manufactured by Kuraray Co., Ltd.)
1 part by weight (solid content) Colloidal silica (Snowtex 30 manufactured by Nissan Chemical Co., Ltd.)
1.5 parts by weight (solid content) paraffin wax emulsion (Cellosol 428 manufactured by Chukyo Yushi Co., Ltd.)
0.3 parts by weight (solid content) polytetrafluoroethylene particles (Polyflon D-1 manufactured by Daikin Industries, Ltd.)
0.5 parts by weight (solid content)────────────
────────────────────────

0
[088] The obtained heat-sensitive recording material was heated to 30°C and a relative humidity of 85%.
%, when I printed using a G3 mode facsimile machine, where sticking is likely to occur, the printing was good with almost no curling or skipping.

Comparative example. A light- and heat-sensitive recording material was obtained in exactly the same manner as in Example 1, except that 4-fluoroethylene particles were not used, and a printing test was conducted in the same manner.

The results of these Examples and Comparative Examples demonstrate that by incorporating a fluorine-based polymer into the protective layer, the sticking of transparent photosensitive viewing recording materials can be significantly improved without deteriorating the transparency. It is something to prove.

Claims (1)

[Claims] 1. A light and heat sensitive recording material comprising, on a support, at least a heat sensitive layer containing a photodegradable diazo compound and a coupler separated by a microcapsule wall and a protective layer, the heat sensitive layer comprising: However, at least a coating solution containing microcapsules each independently encapsulating a diazo compound and a coupler, or a microcapsule containing one of a diazo compound or a coupler and emulsifying the other diazo compound or coupler that has not been microencapsulated. A transparent photosensitive and heat-sensitive layer formed by applying and drying a coating solution containing a dispersion, and the protective layer is a protective layer containing a fluorine-based polymer. Heat-sensitive recording material.