JPH09156215A - Photosensitive thermal recording material and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method recording good image high in color forming properties only by the heating by a thermal head and simple exposure without generating fog at a time of preservation by forming a recording image by using two energies of heat and light and a fixing type photosensitive thermal recording material incapable of altering the recording image. SOLUTION: This recording material is constituted so as to provide an optical color forming element consisting of a compd. decomposed by light and an element reacting with the decomposition product to form a color on a support. In this case, the optical color forming element is mixed by heat to form a latent image and this latent image forms a color by light and at least one component of the optical color forming element is dispersed along with an org. solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light and heat sensitive recording material which develops a color by being irradiated with light after being heated and a recording method using the same.

[0002]

2. Description of the Related Art A thermal recording material using a thermal head has features that a recording apparatus is simple, no development is required, no noise is generated during recording, maintenance is unnecessary, and running cost is low. Therefore, it is widely used in various fields such as facsimiles and printer labels.

Although ordinary heat-sensitive recording materials have the above-mentioned advantages, they are unnecessary when storing, especially when they are stored in a place of high temperature and high humidity for a long period of time, because a color reaction occurs only by heating. It was unavoidable that the color development of.

On the other hand, a light-sensitive recording material capable of forming a color image only by applying imagewise light irradiation has long been known as a free radical photograph. For example, Ph
ot. Sci. Eng ,. 5,98-103 (196
1), JP-B-43-29407, JP-A-55-553
35, JP-A-57-60329, and JP-A-62-66.
No. 254, etc., a photoaryl radical generated by irradiation of ultraviolet rays is used to obtain a color image by oxidizing various leuco dyes, or a reaction of the photohalogen radical generated with an aniline derivative is used to produce triarylmethane. A method of forming a dye of the system to obtain a color image is disclosed.

Further, there is also an image forming material such as Dylux ^R manufactured by Du Pont, which forms an image by exposing it to UV light and then activates a photoreducing substance with visible light to fix the image. The fact that an image can be formed simply by irradiating light through a document has the advantage that the device and operation used are simple, but since it also has the property of developing color only with light, its handling Had the drawback of being forced to work in a dark room and of having poor stability during storage.

As an example of applying the coloring principle of free radical photography to thermal recording, JP-A-1-129247, 1-
Nos. 143252, 3-10252, and 3-1983 disclose recording materials in which a photo-radical generator and a leuco dye are enclosed in a thermoresponsive microcapsule and a reducing agent is present outside the capsule. In the recording material, a reducing agent outside the microcapsules is mixed with a photo free radical generating agent inside the microcapsules by thermal recording, and after the coloring property is stopped, the entire surface is exposed to color the non-heated part. Can be made. In this type of thermal recording material,
The recording apparatus may be equipped with a thermal head and a light source necessary for exposing the entire surface, and recording can be performed by a simple operation without impairing the advantages of ordinary thermal recording.

However, in the above-mentioned recording material, since the oxidative coloring type leuco dye which reacts with the photo-radical generating agent to form a color is mixed from the beginning, it is exposed to room light, sunlight or the like during storage and long-term. There is a drawback that fogging occurs due to the gradual decomposition of the photo free radical generator during storage for a certain period, and there has been a demand for a recording material that can be handled more easily and can withstand long-term storage.

Further, Japanese Patent Application Laid-Open No. 60-2393 discloses a light and heat sensitive recording material containing a photo free radical generator and an oxidative coloring type leuco dye in a separated state at room temperature. This light and heat sensitive recording material separates the photo free radical generator and the oxidative coloring type leuco dye by solid dispersion, so if a high coloring density is to be achieved, the photo free radical generator and leuco dye are sufficiently dissolved and mixed. However, there is a drawback in that the components that have been once melted and mixed cool down and precipitate and separate between the time of receiving heat recording and the time of receiving light, resulting in deterioration of color developability. Was.

Further, in Japanese Patent Application Laid-Open No. 7-237354, a light and heat sensitive recording material (hereinafter also simply referred to as a recording material) in which a specific pyrazolone compound and a specific phenol compound and a salicylic acid derivative as a color-forming aid are dispersed and coated. )
Is disclosed. In this, the latent image can be colored by irradiation with ultraviolet rays after the three are mixed by heating to form a latent image. Although the coloring mechanism of this recording material is not clear, it is considered that the pyrazolone compound is decomposed to form a coloring dye, and the photodecomposition is promoted by the phenol compound and the salicylic acid derivative.

As described in the above publication, the pyrazolone compound alone decomposes and develops color under high temperature conditions. Again, fogging occurs during long-term storage, especially when temperature and humidity are high. There is a drawback that it occurs or the background part is colored after image recording, and also in this case, if the dissolution and mixing by heating with the thermal head is insufficient,
It was found that the color density was low.

Moreover, all of the above three types of compounds are
Since it does not decompose by light when it exists alone before heating and mixing, the non-recorded area is unfixed, and the uncolored area is reheated and irradiated with light to easily tamper with the recording. .

[0012]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to solve the problems of the prior art described above, and to record a recorded image using two energies of heat and light. An object of the present invention is to provide a light and heat sensitive recording material and a recording method capable of obtaining a good image with high color developability by forming the image without causing fogging during storage and only by heating with a thermal head and simple exposure.

Further, the problems to be solved by the present invention are as follows.
An object of the present invention is to provide a fixing type light and heat sensitive recording material in which a recorded image cannot be falsified.

[0014]

The above object of the present invention is achieved by the following constitution.

1. In a light and heat sensitive recording material provided with a photo-coloring element comprising a compound which decomposes by light and an element which reacts with a decomposition product thereof on a support, the photo-coloring element is mixed by heat to form a latent image. A light- and heat-sensitive recording material, wherein the latent image is colored by light, and at least one of the light-coloring elements is dispersed together with an organic solvent.

2. 2. The light and heat sensitive recording material according to the above 1, wherein at least one of the compound that decomposes by light and the element that develops a color by reacting with the decomposition product is encapsulated in microcapsules.

3. 2. The light and heat sensitive recording material as described in 1 above, wherein the compound decomposed by light is a photo free radical generator.

4. 2. The light and heat sensitive recording material according to the above 1, wherein the element that develops a color by reacting with the decomposition product is a leuco dye of an oxidative color development type.

5. 2. The light and heat sensitive recording material according to the above 1, wherein the elements that develop color by reacting with the decomposition products are a coupler and an aromatic primary amine compound.

6. 2. The light and heat sensitive recording material as described in 1 above, wherein the compound that decomposes by light is an aromatic azide compound, and the element that reacts with the decomposition product to develop a color is a coupler.

7. 2. The light and heat sensitive recording material as described in 1 above, wherein the color developability of the photocolor-forming element other than the latent image formed by being mixed by heat is stopped by light.

8. A recording material in which a photo-coloring element including a compound that decomposes by light and an element that develops a color by reacting with a decomposition product thereof is provided on a support, and at least one of the photo-coloring elements is dispersed together with an organic solvent. The recording method to be used, wherein a latent image is formed by mixing the photo-coloring elements by heat, and the latent image is colored by light.

9. A recording method using a light and heat sensitive recording material provided with a photo-coloring element on a support, wherein a latent image is formed by mixing the photo-coloring element by heat, and the latent image is colored by light. At the same time, the recording method is characterized in that the color-forming property of the photo-coloring element other than the latent image is stopped.

In the light and heat sensitive recording material of the present invention, the compound which is decomposed by light on the support is decomposed by irradiating with light, and is reacted with the decomposition product to react with the element which develops color, An image is formed by forming a dye and developing a color.

In the non-heated portion, the photoreactive compound and the element that reacts with its decomposition product are not in a mixed state, so that the reaction of irradiating light does not cause the reaction of forming the dye. Only the decomposition reaction of the compound that is decomposed by light occurs. Therefore, after the compound that decomposes by light and the element that develops a color by reaction with the decomposition product are all mixed by heating, the color is developed only when light is irradiated to form an image.

In the light and heat sensitive recording material of the present invention, the recording device may be a normal heat recording device provided with a light source such as a fluorescent lamp, and a good color image can be obtained without impairing the advantages of the heat recording. it can. In addition, the element that develops color by reacting with a compound that decomposes by light and its decomposition product is
Since it is not mixed when it is not heated, even if it is exposed to room light etc. during storage, or if the compound that decomposes by light during long-term storage partially decomposes, unnecessary color reaction does not occur and its handling is easier. Become.

The present invention will be described in detail below.

The compound which is decomposed by light may be any compound which is decomposed by light such as ultraviolet light, visible light or infrared light, and includes, for example, those called photo-free radical generators, diazonium compounds and azide compounds. Be done. Examples of the photo free radical generator include 2,4,6-triarylimidazole dimer compounds described in JP-B-62-39728 and JP-B-63-2099, and U.S. Pat. No. 3,282,693.
Azide compounds such as 2-azidobenzoxadiazole, benzoyl azide and 2-azidobenzimidazole described in U.S. Pat. No. 3,615,568;
Ethyl-1-methoxy-2-pyridothiocyanine perchlorate, 1-methoxy-2-methylpyridinium-p
-Pyridinium compounds such as toluene sulfonate, N-
Bromosuccinimide, tribromomethylphenyl sulfone, diphenyliodine, 2-trichloromethyl-5
(P-Butoxystyryl) -1,3,4-oxadiazole, 2,6-bis (trichloromethyl) -4- (p-
(Methoxyphenyl) -s-triazine and other organic halogen compounds, benzophenone, thioxanthone, anthraquinone, benzoin ether and other carbonyl compounds, azobisisobutyronitrile and other azo compounds, alkyl disulfides, mercaptans and other organic sulfur compounds, triphenylphosphine Examples of such phosphorus compounds are:

The wavelength of light which is decomposed by the compound which is decomposed by light can be selected in consideration of easiness of handling as a recording material, availability of a light source to be used and cost.
The ease of handling as a recording material may be limited, for example, if the photosensitive material is sensitively exposed to light having a wavelength similar to that of room light, because it has a problem in stability and must be handled in a dark room. In order to avoid such a restriction, it is preferable to use a region from the ultraviolet region to a part of visible light or infrared light. Among them, the energy level is 300nm, which eliminates the need for expensive materials such as quartz.
It is preferable to use light in the 450 nm region.

A compound which is decomposed by light is decomposed by light and then is reacted with the decomposition product to generate a color by the reaction with an element which is colored. In this case, the decomposition product is formed. May be formed as a part of the above, or may be changed to a compound different from the dye only by being involved in the dye forming reaction. It depends on the combination of a compound that decomposes by light and an element that develops a color by reacting with the decomposition product, but it is selected in consideration of the generation efficiency, color tone, fastness, extinction coefficient, etc. of the dye formed by the reaction. .

As the reaction for reacting the photodecomposable compound of the present invention and the decomposition product thereof to form a coloring dye, various reactions can be utilized, but the following three types are preferable.

[0032] (In the above reaction formula, A represents a photodegradable compound,
A'represents a photolysis product. Also, B, C and D are A '
Represents an element that develops color in response to. Also, D'B-C,
AC represents the formed coloring dye. B 'is a form in which B is changed by the reaction with A'. The above reaction formulas are schematic representations of each type of reaction, and are useful for understanding what the dye skeleton produced is derived from. In the above reaction formula, the element that develops color by reacting with A'is described as consisting of a single compound (types 1 and 3) and two types of compounds (type 2). It may consist of more than one type. Further, although an auxiliary component (for example, a base or an acid) that accelerates the dye-forming reaction is not described, it may be contained in the photo-coloring element. That is, in the case of type 1, D reacts with the photodegradation product of A and D to form a coloring dye by oxidation, decomposition, etc., and the basic skeleton of the coloring dye is derived from D. .

In the case of the type 2, B, which is one of the color-forming elements, is activated by a certain change (for example, oxidation or decomposition) by the reaction with A ', and then the other color-forming element is activated. It reacts with C (for example, a coupling reaction or the like) to form a coloring dye. In this case, the basic skeleton of the coloring pigment produced is derived from B and C.

In the case of the type 3, A'reacts with C to form a coloring dye (for example, a coupling reaction), but unlike the type 1, the basic skeleton of the coloring dye formed is A. And C.

As an example of the type 1, a compound which is decomposed by light is a photo free radical generator such as a 2,4,6-triarylimidazole dimer compound or an organic halogen compound, and a decomposition product thereof is obtained. The case where the element to react is like a leuco dye is mentioned.

In this case, the decomposition products produced by light irradiation are imidazolyl free radicals and halogen free radicals, which have a strong oxidizing power. Utilizing the oxidizing power, for example, a leuco dye can be oxidized into a coloring dye. Examples of leuco dyes that can be used include U.S. Pat. No. 3,445,445.
Those described in Japanese Patent No. 234 can be used, and typical structures are as follows.

1) Aminotriarylmethane 2) Aminoxanthene 3) Aminothioxanthene 4) Amino-9,10-dihydroacridine 5) Aminophenoxazine 6) Aminophenothiazine 7) Aminodihydrophenazine 8) Aminodiphenylmethane 9) Leucoin Damine 10) Aminohydrocinnamic acid (cyanoethane, leucomethine) 11) Hydrazine 12) Leucine digoid dye 13) Aminodihydroanthraquinone 14) 4,4'-biphenol 15) 2- (p-hydroxyphenyl) -4,5-diphenylimidazole 15) Phenethylaniline Specific examples of compounds include leuco crystal violet, tris (4-dimethylamino-o-tolyl) methane, bis (4-dimethylamino-o-tolyl) phenylmethane, and biphenyl. Sus (4-dimethylamino-o-tolyl) thienylmethane, 2- (2-chlorophenylamino-6-
N, N-dibutylamino-9- (2-methoxycarbonyl) -phenylxanthene, 2-N, N-dibenzylamino-6-N, N-diethylamino-9- (2-methoxycarbonyl) phenylxanthene, benzo [ a] -6
-N, N-diethylamino-9- (2-methoxycarbonyl) phenylxanthene, benzoylleucomethylene blue, benzoyl-3,7-diethylaminophenoxazine, benzoyl-3,7-diethylamino-9-phenyldihydrophenazine, 6,6 '. -Di-t-butyl-p, p'-bi-o-cresol and the like can be mentioned.

Among them, preferable leuco dyes are triarylmethane type leuco dyes such as tris (4-dimethylamino-o-tolyl) methane, benzoyl leuco methylene blue, benzoyl-3,7-diethylaminophenoxazine and benzoyl-3. Examples thereof include acylated leucoazine dyes such as 7,7-diethylamino-9-phenyldihydrophenazine. Further, as the photo-free radical generator used in combination with the above leuco dye, 2,4,6-triarylimidazole dimer compound, tribromomethylphenyl sulfone, 2,6
Examples thereof include organic halogen compounds such as -bis (trichloromethyl) -4- (p-methoxyphenyl) -s-triazine.

Further, these photo-radical generating agents can be sensitized with intrinsic sensitivity and spectral sensitivity by using various sensitizers together. Representative sensitizers include, for example, Katsumi Tokumaru and Shin Okawara, “Sensitizer”, Kodansha, 1987, 6
The compounds described on page 4-75 can be mentioned.

As an example of the type 2, a compound which is decomposed by light is a photo-radical generator having an oxidizing power similar to the type 1, and an element which reacts with the decomposition product to form a color is
Examples include couplers and aromatic primary amines. For example, an aromatic primary amine such as N, N-diethyl-p-phenylenediamine or 4-aminoantipyrine forms an azomethine dye by oxidative coupling with a phenol or an active methylene compound. As is well known in the field of photosensitive materials,
The above-mentioned free radicals can be used to cause an oxidative coupling reaction to produce a dye.

Examples of aromatic primary amines that can be used include p-aminophenol, other than the above-mentioned amines.
N, N-diethyl-2-methyl-p-phenylenediamine, N-ethyl-N-methanesulfonylaminoethyl-
Examples thereof include 2-methyl-p-phenylenediamine and N, N-didodecyl-p-phenylenediamine. The above-mentioned aromatic primary amine can be used in the form of a hydrochloride, a sulfate, a tosylate, a perfluoroalkyl sulfonate, etc., if necessary. As the acyl body, for example, acetyl body, benzoyl body, p-toluenesulfonyl body, (2,4-di-t-pentyl-phenoxy) acetyl body, and p-dodecyloxyphenylsulfonyl body can be similarly used.

Among these, preferred aromatic primary amines include aminoantipyrine and its analogs, perfluoroalkyl sulfonates of N, N-dialkylamino-p-phenylenediamine derivatives, and the like.

As the coupler which forms a dye by oxidative coupling with an aromatic primary amine, those known in the field of silver halide color photographic light-sensitive materials can be used. Examples of couplers that can be used include U.S. Pat.
772, 162, 2,895,826, 3,0
02,836, 3,034,892, 2,47
4,293, 2,423,730, 2,36
No. 7,531, No. 3,041,236, No. 4,33
No. 3,999, No. 2,600,788, No. 2,36
9,869, 2,343,703, 2,31
1,082, 3,152,896, 3,51
9,429, 3,062,653, 2,90
8,573, 2,875,057, 2,40
7,210, 3,265,506, 2,29
8,443, 3,048,194, 3,44
No. 7,928 and Agfa Mitteilunge
Farbkuppler-eine Litera of n
turuberesiicht, Volume III 112-17
It is described in representative patents and publications such as page 5 (1961).

Among them, examples of preferable couplers include phenols, naphthols, pyrazolones, pyrazolotriazoles, acylacetanilides and the like. Further, both a so-called 2-equivalent coupler in which a leaving group is substituted at the active site of the coupler and a 4-equivalent coupler in which the active site is not substituted can be used. Also, the reaction with the coupler may be accelerated by using a base,
A base may be used in combination if necessary.

As the base, triphenylguanidine,
Organic bases such as trihexylamine, pyridine and quinoline, inorganic bases such as sodium hydrogencarbonate, potassium carbonate, potassium hydroxide and salicylic acid metal salts, or metal salts of organic acids can be used.

An example of the type 3 is a case where the compound which is decomposed by light is an aromatic azide, and the element which develops a color by reacting with the decomposition product is a coupler. When an aromatic azide compound is decomposed by light, nitrene is produced. The produced nitrene can produce an azomethine dye by the reaction with the above-mentioned coupler.

Examples of aromatic azide compounds that can be used include 4- (N, N-diethylamino) phenyl azide, 2,5-dibutoxy-4-morpholinophenyl azide, 2,5-dibutoxy-4-phenylthiophenyl azide, 4- (N-ethyl-N-methylsulfonylaminoethylamino) -2-methylphenyl azide, 4-diethylamino-3-dodecyloxycarbonylphenyl azide, 1-naphthyl azide, 2-naphthyl azide, anthranil azide, 3-quinoline azide, 9-acridine azide or the like can be used. Examples of preferred aromatic azides include p-dialkylaminophenyl azides. Moreover, as the coupler which forms a dye by coupling with an azide, the same ones as mentioned above can be mentioned.

In the present invention, the total number of carbon atoms of each component of the element that develops color by reacting with a compound that decomposes by light and its decomposition product is 10 or more in order to increase the solubility in the organic solvent used. Is preferred. When the molecular weight becomes too high, the color density per unit weight tends to decrease, so that the total carbon number is more preferably in the range of 15 to 40.

In the present invention, all the components of the compound that decomposes by light and the element that reacts with the decomposition product to develop color are not uniformly mixed before heating. At least one component of the element that develops color by reacting with a compound that decomposes by light and its decomposition product needs to be isolated by some means before heating. The isolation method requires isolation that does not cause a color reaction even if a compound which is decomposed by light during storage is partially decomposed.

When it is heated by the thermal head, it is rapidly mixed, and when it is irradiated with light, the color-developing reaction occurs only in the mixed portion. When heated by this thermal head, the photochromic elements are rapidly dissolved and mixed, and if the dissolved state can be maintained without precipitating individual components until the photoirradiation, a high color density can be obtained. However, for that purpose, it is very effective to disperse at least one component of the photochromic element together with an organic solvent.

As the usable organic solvent, those having a high boiling point are preferable.

For example, phosphoric acid ester, phthalic acid ester, acrylic acid ester, methacrylic acid ester and other carboxylic acid ester, fatty acid amide, alkylated biphenyl, alkylated terphenyl, chlorinated paraffin,
Alkylated naphthalene, diarylethane, dialkylphenol and the like are used.

Specifically, JP-A-60-242094,
Those described in JP-A-62-75409 can be used. The boiling point of the organic solvent used is preferably 100 because it is desired that it does not volatilize at room temperature.
Those above ℃ are used. If the boiling point is too high, the viscosity tends to be high, and more preferably 12
Those in the range of 0 ° C to 500 ° C are used.

In addition to the above-mentioned high-boiling point organic solvent, a low-boiling point organic solvent such as ethyl acetate or methylene chloride may be used in combination as a dissolution aid.

As the isolation method which can be used, it is possible to avoid uniform mixing by, for example, emulsifying and dispersing each component or solid-dispersing each component. Further, for more reliable isolation, the components to be isolated at the time of storage are divided into separate layers on the support and applied. It is also effective to provide an intermediate layer between each layer.

A more preferable form of isolation is to use microcapsules.

The microcapsules preferred in the present invention prevent contact between substances inside and outside the capsule at room temperature due to the substance sequestering action of the walls of the microcapsules, and increase the permeability of the substance when heated at a certain temperature.

The permeability of the microcapsules depending on the temperature is
It can be controlled by changing the glass transition temperature of the capsule wall depending on the capsule wall material, core substance, additive species and the like.

The wall material of the microcapsule usable in the present invention includes polyurethane, polyurea, polyether polycarbonate, urea-formaldehyde resin, melamine-formaldehyde resin, polystyrene, styrene-methacrylate copolymer, gelatin, polyvinylpyrrolidone, polyvinyl alcohol. Etc. A plurality of these wall materials may be used in combination.

In the present invention, among the above wall materials, polyurethane, polyurea, polyamide, polyester, polycarbonate, polyester and the like are preferable, and polyurea and polyurethane are particularly preferable.

For details of the microcapsules which can be preferably used in the present invention, see US Pat. No. 3,79.
No. 6,696.

The microcapsules used in the present invention are obtained by interfacial polymerization in which a core substance containing a substance to be encapsulated is emulsified, and then a wall of a polymer substance is formed around the oil droplets for microcapsulation. The method is preferred.

At this time, it is preferable to use an organic solvent to form emulsified oil droplets, if necessary, and the organic solvent to be used can generally be appropriately selected from high boiling point organic solvents.

For example, phosphoric acid ester, phthalic acid ester, acrylic acid ester, methacrylic acid ester and other carboxylic acid ester, fatty acid amide, alkylated biphenyl, alkylated terphenyl, chlorinated paraffin,
Alkylated naphthalene, diarylethane and the like are used.

Specifically, JP-A-60-242094,
Those described in JP-A-62-75409 can be used. In addition to the above high boiling point organic solvent, a low boiling point organic solvent such as ethyl acetate or methylene chloride may be used in combination as a dissolution aid.

On the other hand, the water layer mixed with the oil layer can contain a water-soluble polymer as a protective colloid, and for example, polyvinyl alcohol, gelatin, or cellulose derivative can be used. When emulsifying and dispersing, an appropriate surfactant can be selected from known surfactants to prevent precipitation and aggregation.

Other color-forming elements to be present outside the microcapsules may be dispersed by either solid dispersion or emulsion dispersion, but emulsion dispersion is preferred.

In solid dispersion, emulsion dispersion, and dispersion in the form of using microcapsules, the particle size thereof is preferably in the range of 0.1 μm to 20 μm from the viewpoint of image quality and color density. More preferably, it is in the range of 0.5 μm to 10 μm.

Further, in the present invention, a compound which is decomposed by light is heated, and a color reaction is caused at a site mixed with an element which reacts with the decomposition product to develop a color, but a non-heated portion, that is, a decomposition product. In the part isolated from the element that reacts with and develops color, no color reaction occurs even when irradiated with light. Preferably, when the unheated portion is exposed to light, the compound that decomposes with light decomposes and is converted into a substantially harmless compound by the reaction with surrounding compounds without participating in the color development reaction.

In the present invention, the amount of the compound that decomposes by light and the element that develops a color by reacting with the decomposition product thereof is not particularly limited, but the film thickness when applied on a support, It is selected in consideration of coloring efficiency, coloring density, and the like. The preferred amount of use of each component is 4 × 10
^-4 mol / m ^{2 to} 2 × 10 ^-2 mol / m.
Further, the film thickness when applied onto the support is not particularly limited, but in consideration of heat sensitivity and image sharpness, the dry film thickness is in the range of 0.5 μm to 50 μm. It is more preferably in the range of 1 μm to 20 μm.

The light and heat sensitive recording material in the present invention can be prepared by coating and impregnating a support with a compound which decomposes by light and an element which develops a color by reacting with the decomposition product.

At this time, as the binder of the above dispersion, various emulsions such as polyvinyl alcohol, gelatin, styrene-butadiene latex, carboxymethyl cellulose, gum arabic, polyvinylpyrrolidone, polyvinyl acetate and polyacrylic acid ester can be used. , The amount used is 0.5 to 5 g / m in terms of solid content
²

In the recording material of the present invention, image protection,
It is preferable to provide a protective layer in consideration of prevention of adhesion between recording materials, prevention of adhesion to a thermal head, writing property, smoothness and the like. As the binder for the protective layer, a known binder can be used. For example, methyl cellulose,
Carboxymethyl cellulose, hydroxymethyl cellulose, starches, gelatin, gum arabic, casein, styrene-maleic anhydride copolymer hydrolyzate, polyvinyl alcohol, carboxy-modified polyvinyl alcohol,
Polymer such as polyacrylamide derivative, polyvinylpyrrolidone, sodium polystyrenesulfonate, sodium alginate, styrene-butadiene latex, acrylonitrile-butadiene rubber latex, polyvinyl acetate emulsion, silicone resin, melamine resin, phenol resin, acrylic resin polyester resin, epoxy resin A binder such as a fluororesin, nitrocellulose, cellulose acetate propionate, cellulose acetate, fluorinated vinylidene resin, or chlorinated rubber can be used. As the filler of the protective layer, zinc oxide, calcium carbonate, barium sulfate, titanium oxide, lithobon, talc, roxite, kaolin, aluminum hydroxide, amorphous silica, inorganic pigments such as colloidal silica, polystyrene, polymethylmethacrylate, Polyethylene, vinyl acetate resin, vinyl sulfide resin, vinylidene sulfide resin, styrene-
Methacrylate copolymer, vinylidene chloride, polyurea, melamine-formaldehyde and other organic pigments, zinc stearate, calcium stearate, aluminum stearate and other metal soaps, or paraffin wax,
Waxes such as microcrystalline wax, carnauba wax, methylol stearylamide, polyethylene wax, and silicone can be added. These fillers may be used alone or in combination of two or more.

When the light and heat sensitive recording material of the present invention is coated on a support such as paper or synthetic resin film, a generally well-known coating method can be used.

For example, a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a doctor coating method, a wire bar coating method, a slide coating method, a gravure coating method, a spin coating method or an extrusion coating method is used. can do.

As the support which can be used in the light and heat sensitive recording material of the present invention, paper, regenerated cellulose, cellulose acetate, cellulose nitrate, polyethylene terephthalate, polyethylene, polyvinyl acetate, polyethylene naphthalate, etc. film, glass, Wood, metal, etc. are mentioned.

The light source which can be used in the present invention may be any light source capable of decomposing a compound which is decomposed by light, such as a fluorescent lamp, a high pressure mercury lamp, a halogen lamp, a xenon lamp, a tungsten lamp or sunlight. And so on.

[0078]

EXAMPLES Examples are shown below, but the present invention is not limited to these examples. In addition, "part" indicating the addition amount indicates "part by weight".

Example 1 (Preparation of capsule liquid A) Leuco dye: benzoyl leuco methylene blue 1.0 part Wall material: xylylene diisocyanate / trimethylolpropane adduct 15 parts Additive: dodecylbenzenesulfonic acid 0.4 part Dissolution aid Agent: Methylene chloride 5 parts High boiling solvent: 1-phenylene-1-xylylethane (boiling point 312 ° C.) 5 parts was uniformly dissolved.

This solution was added to 54 parts of a 6% aqueous solution of polyvinyl alcohol and emulsified and dispersed at 20 ° C. using a homogenizer to obtain an emulsion having an average particle size of 1 μm. 60 parts of water was added to the obtained emulsion and stirring was continued at 40 ° C. for 3 hours. Thereafter, the temperature was returned to room temperature to obtain capsule liquid A. The glass transition temperature of the capsule wall was 80 ° C.

(Preparation of Photo-Free Radical Generator Dispersion Liquid) 30 parts of tribromomethylphenyl sulfone was added to 150 parts of 4% polyvinyl alcohol aqueous solution and dispersed by a sand mill.
A tribrumomethylphenyl sulfone dispersion having an average particle size of 1 μm was obtained.

Next, a coating solution having the following composition was prepared.

12 parts of the above capsule liquid A 3 parts of the above photo free radical generator dispersion liquid This coating liquid is applied to a high quality paper with a wire bar so that the coating amount of the capsule liquid A and the capsule liquid B leuco dye becomes 0.5 g / m ² . Thus coated and dried at 50 ° C. to obtain the light and heat sensitive recording paper of the present invention.

Example 2 A light and heat sensitive recording paper of the present invention was obtained in the same manner as in Example 1 except that the leuco dye of the capsule liquid A used in Example 1 was replaced with an equimolar amount of leuco crystal violet.

Example 3 Coupler: 2,4-dichloro-3-ethyl-6- [2- (2,4-di-shartypentylphenyloxy) butanoylamino] phenol 1.5 parts Additive: dodecylbenzenesulfone Acid 0.4 parts Walling agent: Xylylene diisocyanate / trimethylolpropane adduct 15 parts Dissolution aid: Ethyl acetate 5 parts High boiling solvent: Isopropylbiphenyl (boiling point about 295 ° C) 5 parts were uniformly dissolved.

This solution was added to 54 parts of a 6% aqueous solution of polyvinyl alcohol and emulsified and dispersed at 20 ° C. using a homogenizer to obtain an emulsion having an average particle size of 1 μm. 60 parts of water was added to the obtained emulsion and stirring was continued at 40 ° C. for 3 hours. Thereafter, the temperature was returned to room temperature to obtain capsule liquid B.

(Preparation of Photo-Free Radical Generator / Amine Dispersion) 2,2′-Bis- (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenylimidazole 5 parts N, N-dioctylamino -P-phenylenediamine 10 parts triphenylguanidine 5 parts methylene chloride 30 parts tricresyl phosphate (boiling point about 265 ° C / 10 mmHg) 30 parts was added to 200 parts of 4% polyvinyl alcohol aqueous solution and ultrasonically dispersed to form a dispersion liquid. Obtained.

Next, a coating solution having the following composition was prepared.

Capsule solution B 10 parts Photo free radical generator / amine dispersion 20 parts This coating solution was applied to a fine paper with a wire bar so that the amount of the coupler applied was 0.35 g / m ² , and 50 It was dried at ℃, to obtain a light and heat sensitive recording paper of the present invention.

Example 4 (Preparation of Capsule Liquid C) Azide: 4-morpholino-2,5-dibutoxyphenyl azide 3 parts High boiling solvent: diisopropylnaphthalene (about 318 ° C.) 10 parts Wall material: xylylene diisocyanate / tri Methylolpropane adduct 8 parts Dissolution aid: Ethyl acetate 5 parts were uniformly dissolved.

This solution was added to 46 parts of an 8% phthalated gelatin aqueous solution, and 18 parts of water and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate were emulsified and dispersed at 20 ° C. using a homogenizer to obtain an average particle size. A 1 μm emulsion was obtained. After 20 parts of water was added to the obtained emulsion to homogenize it, stirring was continued at 40 ° C. for 3 hours. Thereafter, the temperature was returned to room temperature to obtain capsule liquid C.

(Preparation of Coupler Dispersion) 7-Chloro-6-tert-butyl-3- (3-dodecylsulfonylpropyl) pyrazolo [3,2-c] triazole 4 parts Triphenylguanidine 2 parts Tricresyl phosphate 1 32 parts of gelatin (15% aqueous solution), dodecylbenzenesulfonic acid (5 parts of 10% aqueous solution, water 30 parts).
Parts were added, and the mixture was emulsified and dispersed at 20 ° C. for 10 minutes using a homogenizer, the resulting emulsion was stirred at 40 ° C. for 2 hours to remove ethyl acetate, and then the volatilized ethyl acetate coating water was added by hydration. In addition, a coupler dispersion was obtained.

Next, a coating solution having the following composition was prepared.

Capsule liquid C 6 parts Coupler dispersion liquid 8 parts Gelatin (15% aqueous solution) 2 parts Water 4.5 parts This coating solution was applied to a fine paper with a wire bar so that the amount of azide applied was 0.2 g / m ^2. And then dried at 50 ° C. to obtain a light and heat sensitive recording paper of the present invention.

Comparative Example 1 When preparing the capsule liquid of Example 1, 1 phenyl-1
Comparative Sample-1 was prepared in the same manner as in Example 1 except that xylylethane was not added.

Comparative Example 2 Comparative sample-2 was prepared according to Example 1 of JP-A-3-1983 as follows.

Leuco Dye: Leuco Crystal Violet 1.5 parts Photo Oxidizer: 2,2'-bis- (o-chlorophenyl) -4,4 ', 5,5'-tetraphenylimidazole 3.0 parts Walling agent: Xylylene diisocyanate / trimethylol propane adduct 24 parts Dissolution aid: Methylene chloride 5 parts High boiling point solvent: Tricresyl phosphate 24 parts are mixed and this solution is mixed with 63 parts of 8% polyvinyl alcohol aqueous solution and 100 parts of distilled water. Was added to an aqueous solution consisting of and was emulsified and dispersed at 20 ° C. using a homogenizer to obtain an emulsion having an average particle size of 1 μm. The stirring was continued at 40 ° C. for 3 hours. Thereafter, the temperature was returned to room temperature to obtain a capsule liquid.

Next, 42 g of phenidone A (1-phenylpyrazolidinedione-3-one) was added to diethyl maleate 8
g and 30 g of ethyl acetate. The resulting solution is 8
% Polyvinylalcohol aqueous solution 100 g and an aqueous solution of sodium dodecylbenzenesulfonate 0.5 g,
It was emulsified and dispersed using a homogenizer to obtain a phenidone A-containing emulsion dispersion.

9 parts of the above-mentioned capsule liquid and 7 parts of the above-mentioned phenidone A-containing emulsion dispersion were mixed and coated on a high-quality paper with a wire bar so that the coating amount of the leuco dye was the same as in Example 1, and the temperature was 50 ° C. Comparative sample-2 was obtained by drying. Contrary to the light and heat sensitive recording material of the present invention, no color was developed at the part subjected to heating and exposure, but color was exhibited at the part exposed only.

(Coloring / Raw Storage Test) The obtained light and heat sensitive recording paper was heated at 120 ° C. for 5 seconds (0.5 kg / m ² ) using a thermal tilt tester (manufactured by Toyo Seiki). After that, the entire surface was exposed for 30 seconds using a high pressure mercury lamp.

Further, before recording, the light and heat sensitive paper was stored under high temperature and high humidity (50 ° C., 80%) conditions for 3 days, and then the same operation was carried out to measure the densities of the background part and the colored part.

[0102]

[Table 1]

From the above results, in the light and heat sensitive recording material and recording method of the present invention, the coloring property of the heating recording part is good, and even after storage under high temperature and high humidity, the increase of fog in the non-heating part is small. it is obvious.

(Fixability Test) The samples obtained in Examples 1 to 4 were exposed to light over a whole area of a high pressure mercury lamp for 1 minute and then heated again.
Exposure was repeated, but no significant color development was observed compared to the sample before heating and exposure. Therefore, it was confirmed that the color forming property of the portion where the latent image was not formed by heating was stopped.

[0105]

The light and heat sensitive recording material and the recording method according to the present invention form a recorded image by using two energies of heat and light, so that the thermal head can easily perform heating without causing fog during storage. A good image with high color developability can be obtained only by exposure, and the recorded image cannot be falsified.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Osamu Hatano 1 Konica Stock Company, Sakura Town, Hino City, Tokyo (72) Inventor Tetsuya Yoshida 1 Konica Stock Company, Sakura Town, Hino City, Tokyo (72) Inventor Shuji Kida 1st Sakura-cho, Hino-shi, Tokyo Konica Stock Association In-house

Claims (9)

[Claims] 1. A light and heat sensitive recording material provided with a photochromic element comprising a compound decomposable by light and an element which develops a color when reacted with the decomposition product on a support, wherein the photochromic element is mixed by heat. A light and heat sensitive recording material, wherein a latent image is formed and the latent image is colored by light, and at least one of the light coloring elements is dispersed together with an organic solvent. 2. At least one of the compound which decomposes by the light and the element which develops a color by reacting with the decomposition product.
The light and heat sensitive recording material according to claim 1, wherein the seeds are encapsulated in microcapsules. 3. The light and heat sensitive recording material according to claim 1, wherein the compound decomposed by light is a photo free radical generator. 4. The light and heat sensitive recording material according to claim 1, wherein the element that develops a color by reacting with the decomposition product is an oxidative coloring type leuco dye. 5. The light and heat sensitive recording material according to claim 1, wherein the elements that develop color by reacting with the decomposition products are a coupler and an aromatic primary amine compound. 6. The light and heat sensitive recording material according to claim 1, wherein the compound that decomposes by light is an aromatic azide compound, and the element that reacts with the decomposition product to develop a color is a coupler. 7. The light and heat sensitive recording material according to claim 1, wherein the color forming properties of the photo color forming elements other than the latent image formed by mixing by heat are stopped by light. 8. A photochromic element comprising a compound which decomposes by light and an element which develops a color by reacting with a decomposition product thereof is provided on a support, and at least one of the photochromic elements is dispersed together with an organic solvent. In the recording method using the recording material described above, a latent image is formed by mixing the photo-coloring elements by heat, and the latent image is colored by light. 9. A recording method using a light and heat sensitive recording material having a photo-coloring element provided on a support, wherein a latent image is formed by mixing the photo-coloring element with heat, and the latent image is exposed by light. A recording method for causing color development, and at the same time, stopping the color development of the photo-coloring elements other than the latent image.