JPH0532042A - Thermal recording material - Google Patents

Abstract

PURPOSE:To provide the above recording material capable of obtaining an image of excellent image quality reduced in gloss. CONSTITUTION:In a thermal recording material wherein a recording image 18 observed on the side of a transparent support, a thermal recording layer is provided to one surface of the transparent support and a layer preventing light reflection is provided to the other surface thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording material, and more particularly to a heat-sensitive recording material having low gloss and excellent image quality.

[0002]

2. Description of the Related Art In a thermal recording method, (1) development is unnecessary, (2) when the support is paper, the paper quality is close to that of ordinary paper,
(3) Easy to handle, (4) High color density,
(5) Since the recording device is simple and inexpensive, and (6) there is no noise at the time of recording, the application is expanding to the field of facsimiles and printers, the field of labels in POS and the like. For this reason, the demand for heat-sensitive recording materials has diversified, and transparent heat-sensitive recording materials for multi-color recording and overhead projectors (hereinafter referred to as OHP) have been developed (for example, JP-A-63-45084).
issue).

In recent years, ultrasonic scanners, CT
With the computerization of medical devices such as scanners and X-rays, transparent heat-sensitive recording materials that can directly record these digital images have been developed. In this case, generally, in the diagnosis of a doctor or the like, the image recorded on the thermosensitive recording material is exposed to light from a fluorescent lamp or the like from behind (a device that applies such light is referred to as Schaukasten) to prevent damage to the image on the support side. Observe from.

[0004]

However, when an image recorded on a conventional thermosensitive recording material in which a thermosensitive recording layer is provided on a transparent support is observed from the support side, the surface of the transparent support (thermosensitive recording The surface on which the layer is not provided: the surface is simply referred to below as "smooth", so a highly glossy image is observed, and it is difficult to see the upper eyes, and it is difficult to take a picture of the obtained image because of the gloss. There was a drawback that was.

As a result of intensive studies made by the present inventors to solve the above-mentioned drawbacks, the surface of the transparent support on the side not having the heat-sensitive recording layer is prevented from reflecting light from the back of the viewer to the extent that it does not become opaque. It was found that good results can be obtained by providing such a layer, and the present invention has been completed. Therefore, an object of the present invention is to provide a heat-sensitive recording material which has a low gloss and is capable of obtaining an image of excellent image quality.

[0006]

The above objects of the present invention are as follows.
A heat-sensitive recording material for observing a recorded image from a transparent support side, characterized in that a heat-sensitive recording layer is provided on one surface of the transparent support and a layer for preventing light reflection is provided on the other surface. Achieved by a thermosensitive recording material.

In the present invention, an image is recorded by causing a color former and a developer, which are separated from each other at room temperature, to come into contact with each other by heating to develop a color.

As the color former and the color developer, a combination of an electron-donating dye precursor (color former) and an acidic substance (color former) or a combination of a diazo compound (color former) and a coupling compound (color former) is used. It is preferable to use the former combination, and particularly from the viewpoint of image clarity, the former combination is preferably used.

The electron-donating dye precursor used in the present invention is not particularly limited, but it has a property of developing a color by donating an electron or accepting a proton such as an acid, and a lactone. A generally colorless compound having a partial skeleton such as lactam, sultone, spiropyran, ester or amide, and the partial skeleton of which is ring-opened or cleaved upon contact with a color developer is usually used.

Examples of such electron-donating dye precursors include crystal violet lactone, benzoyl leuco methylene blue, malachite green lactone, rhodamine B lactam, 1,3,3-trimethyl-6'-ethyl-8'-butoxyindolino. Examples include benzospiropyran.

As a developer for these color formers,
An acidic substance such as a phenol compound, an organic acid or a metal salt thereof, an oxybenzoic acid ester is used, and specific examples thereof are described in JP-A-61-291183.

The diazo compound used in the present invention is a compound which reacts with a developer called a coupling component described later to develop a desired hue, and decomposes when receiving light of a specific wavelength before the reaction. However, it is a photodegradable diazo compound that has no color-forming ability even when the coupling component acts.

The hue in this coloring system is mainly determined by the diazo dye produced by the reaction of the diazo compound and the coupling component. Therefore, as is well known,
By changing the chemical structure of the diazo compound or the chemical structure of the coupling component, the coloring hue can be easily changed, and almost any coloring hue can be obtained depending on the combination.

The photodecomposable diazo compound in the present invention mainly means an aromatic diazo compound, and more specifically, a compound such as an aromatic diazonium salt, a diazosulfonate compound, a diazoamino compound or the like. The diazonium salt is
A compound represented by the general formula ArN ₂ ⁺ X ⁻ (wherein
Ar represents a substituted or unsubstituted aromatic moiety,
N ₂ ⁺ represents a diazonium group, and X ⁻ represents an acid anion).

It is generally said that the photolysis wavelength of a diazonium salt is its absorption maximum wavelength. It is known that the absorption maximum wavelength of diazonium salt changes from about 200 nm to about 700 nm depending on its chemical structure ("Photolysis and chemical structure of photosensitive diazonium salt" written by Takahiro Tsunoda and Ao Yamaoka, Japan Photo Journal 29 (4) 197-105
Page (1965). That is, when a diazonium salt is used as a photodecomposable compound, it is decomposed by light having a specific wavelength according to its chemical structure, and if the chemical structure of the diazonium salt is changed, a coupling reaction with the same coupling component can be achieved. The hue of the dye also changes.

A large number of diazosulfonates that can be used in the present invention are known, and they can be obtained by treating each diazonium salt with a sulfite. The diazoamino compound that can be used in the present invention is a compound obtained by coupling a diazo group with dicyandiamide, sarcosine, methyltaurine, N-ethylanthranic acid-5-sulphonic acid, monoethanolamine, diethanolamine, guanidine and the like. Is. Details of these diazo compounds are described in, for example, JP-A-2-
No. 136286.

The coupling component for forming a dye by coupling with the diazo compound (diazonium salt) used in the present invention includes, for example, 2-hydroxy-3-naphthoic acid anilide and resorcin as a starting point. -14
The thing described in 6678 can be mentioned.

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

As the basic substance, a hardly water-soluble or water-insoluble basic substance or a substance which generates an alkali upon heating is used. Examples thereof are inorganic and organic ammonium salts, organic amines, amides, urea and thiourea and their derivatives, thiazoles, pyrroles, pyrimidines,
Examples thereof include nitrogen-containing compounds such as piperazines, guanidines, indoles, imidazoles, imidazolines, triazoles, morpholines, piperidines, amidines, formazines and pyridines. Specific examples of these are described, for example, in JP-A-61-291183. Two or more basic substances may be used in combination.

The color former used in the present invention may be used as a solid dispersant, but from the viewpoint of the raw storability of the thermosensitive recording layer (prevention of fogging), such as preventing contact between the color former and the developer at room temperature, In addition, it is preferable to encapsulate the color former from the viewpoint of controlling the color development sensitivity such that the color is developed with desired heat energy.

Any of an interfacial polymerization method, an internal polymerization method, and an external polymerization method can be adopted for producing the microcapsules which can be used in the present invention. Particularly, a core substance containing a color former is used. It is preferable to employ an interfacial polymerization method in which after emulsifying in a water-soluble polymer-dissolved aqueous solution, a wall of a polymer substance is formed around the oil droplets. The reactant forming the polymer substance is added inside the oil droplet and / or outside the oil droplet.

Specific examples of the polymer substance include polyurethane, polyurea, polyamide, polyester, polycarbonate, urea-formaldehyde resin, melamine resin, polystyrene, styrene methacrylate copolymer,
Examples thereof include styrene-acrylate copolymer. Preferred polymeric substances are polyurethanes, polyureas, polyamides, polyesters and polycarbonates, particularly preferably polyurethanes and polyureas. Two or more polymer substances can be used in combination.

Specific examples of the water-soluble polymer include gelatin, polyvinylpyrrolidone, polyvinyl alcohol and the like. For example, when using polyurea as a capsule wall material, diisocyanate, triisocyanate, tetraisocyanate, polyisocyanate such as polyisocyanate prepolymer, and polyamine such as diamine, triamine, tetraamine, and two amino groups The microcapsule wall can be easily formed by reacting the prepolymer, piperazine or its derivative or the polyol, etc., contained above in an aqueous solvent by an interfacial polymerization method.

Further, for example, the composite wall made of polyurea and polyamide or the composite wall made of polyurethane and polyamide is added, for example, by using polyisocyanate and acid chloride or polyamine and polyol after adjusting the pH of the emulsifying medium to be the reaction liquid. It can be prepared by warming. For details of the method for producing a composite wall composed of these polyurea and polyamide, see JP-A-58-6.
6948.

Further, a solid sensitizer may be added to swell the microcapsule wall when heated. As the solid sensitizer, those which are solid at room temperature and have a melting point of 50 ° C. or higher, preferably 120 ° C. or lower, can be selected and used from among the plasticizers of polymers used for the microcapsule wall. For example, when the wall material is made of polyurea or polyurethane, a hydroxy compound, a carbamic acid ester compound, an aromatic alkoxy compound, an organic sulfonamide compound, an aliphatic amide compound, an arylamide compound and the like are preferably used.

In the present invention, when a diazo compound is used as the color former, a color former may be used. The coloring aid that can be used in the present invention is a substance that increases the coloring density during heating printing or lowers the minimum coloring temperature, lowers the melting point of the coupling component or the diazo compound, or capsule wall. This is to create a situation in which the diazo compound and the coupling component easily react with each other by the action of lowering the softening point of.

Examples of the color-forming assistant include phenol compounds, alcoholic compounds, amide compounds, sulfonamide compounds and the like. Specific examples are p-tert-octylphenol, p-benzyloxyphenol, phenyl p-oxybenzoate, Examples thereof include benzyl carbanylate, phenethyl carbanylate, hydroquinone dihydroxyethyl ether, xylylenediol, N-hydroxyethyl-methanesulfonic acid amide, N-phenyl-methanesulfonic acid amide. These may be contained in the core substance or may be added as a dispersion outside the microcapsules.

In the present invention, the above-mentioned color developer can be used as a solid dispersant, but it is difficult to use in water from the viewpoint of improving the transparency of the thermosensitive recording layer and improving the light transmittance of the thermosensitive recording material. It is also possible to dissolve it in a soluble or insoluble organic solvent and then mix it with an aqueous phase having a water-soluble polymer containing a surfactant as a protective colloid and use it in the form of an emulsion-dispersed dispersion.

The organic solvent used in this case can be appropriately selected from high boiling point oils. Among them, preferable oils include dimethylnaphthalene, diethylnaphthalene, diisopropylnaphthalene, dimethylbiphenyl, diethylbiphenyl, diisopropylbiphenyl, diisobutylbiphenyl, 1-methyl-1-dimethylphenyl-1-phenylmethane, and 1 in addition to esters.
-Ethyl-1-dimethylphenyl-1-phenylmethane, 1-propyl-1-dimethylphenyl-1-phenylmethane, triallylmethane (eg, tritoluylmethane, toluyldiphenylmethane), terphenyl compound (eg, terphenyl) , Alkyl compounds (eg terphenyl), alkylated diphenyl ethers (eg propyl diphenyl ether), hydrogenated terphenyls (eg hexahydroterphenyl), diphenyl ethers and the like. Among these, it is particularly preferable to use esters from the viewpoint of emulsion stability of the emulsified dispersion.

Examples of the esters include phosphoric acid esters (eg, triphenyl phosphate, tricresyl phosphate, butyl phosphate, octyl phosphate, cresyl diphenyl phosphate), phthalic acid esters (dibutyl phthalate, 2-ethylhexyl phthalate, phthalic acid). Ethyl, octyl phthalate, butylbenzyl phthalate), tetrahydrophthalate dioctyl, benzoic acid ester (ethyl benzoate, propyl benzoate, butyl benzoate, isopentyl benzoate, benzyl benzoate), abietic acid ester (ethyl abietic acid, Benzyl abietic acid), dioctyl adipate, isodecyl succinate, dioctyl azelate, oxalate ester (dibutyl oxalate, dipentyl oxalate), diethyl malonate, maleate ester (dimethyl maleate, maleic acid) Diethyl acid, dibutyl maleate), tributyl citrate, sorbate (methyl sorbate, ethyl sorbate, butyl sorbate), sebacate (dibutyl sebacate, dioctyl sebacate), ethylene glycol esters (formic acid monoester) 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, carbonic acid propylene,
Examples thereof include boric acid esters (tributyl borate, tripentyl borate) and the like. Among these, the use of tricresyl phosphate alone or in combination is preferable because the emulsion dispersion stability of the developer is particularly good.

It is possible to use the above oils in combination, or to use in combination with other oils. In the present invention, an auxiliary solvent may be added to the above organic solvent as a low boiling point dissolution aid. As such an auxiliary solvent, for example, ethyl acetate, isopropyl acetate, butyl acetate, methylene chloride and the like can be mentioned as particularly preferable ones.

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

As the surface active agent to be contained in the aqueous phase, an anionic or nonionic surface active agent which does not cause precipitation or aggregation by acting on the protective colloid may be appropriately selected and used. it can. Preferred surfactants include sodium alkylbenzene sulfonate, sodium alkylsulfate, dioctyl sodium sulfosuccinate, polyalkylene glycol (eg, polyoxyethylene nonylphenyl ether), and the like.

In the emulsified dispersion of the present invention, an oil phase containing the above components and an aqueous phase containing a protective colloid and a surfactant are used by a means such as high speed stirring, ultrasonic dispersion or the like which is used for ordinary fine particle emulsification. Then, they can be mixed and dispersed, and easily obtained.

The ratio of the oil phase to the water phase (weight of oil phase / weight of water phase) is preferably 0.02 to 0.6, particularly 0.1.
It is preferable that it is 0.4. If it is less than 0.02, the amount of water phase is too large to be diluted, and sufficient color developability cannot be obtained.
On the contrary, on the contrary, the viscosity of the liquid becomes high, which causes inconvenience of handling and deterioration of coating liquid stability.

When the heat-sensitive layer liquid prepared as described above is coated on the support, a known coating means using a water-based or organic solvent-based coating liquid is used. In this case, in order to apply the heat-sensitive layer liquid safely and uniformly and to maintain the strength of the coating film, in the present invention, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, starches, gelatin, polyvinyl alcohol, carboxy are used as the polymer binder. Modified polyvinyl alcohol, polyacrylamide, polystyrene and its copolymers, polyester and its copolymers, polyethylene and its copolymers, epoxy resins, acrylate and methacrylate resins and their copolymers, polyurethane resins and polyamide resins, etc. It can also be used together with microcapsules.

If desired, pigments, waxes, hardeners, etc. may be added to the heat-sensitive recording layer. The heat-sensitive recording layer should be coated such that the total amount of the color-developing agent and the color-developing agent is 0.1 to 10 g / m ² , and the thickness of the layer is 1 to 10 g.
It is desirable that the coating be performed so that the thickness becomes μm. In the present invention, a protective layer may be provided on the heat-sensitive layer in order to protect the heat-sensitive layer and improve running in an actual machine.

In the present invention, in order to prevent the reflection of light on the surface of the transparent support, a layer containing a polymer binder for preventing light reflection and a fine particulate substance (hereinafter referred to as an antireflection layer) is provided on the transparent support surface. ) Is provided. As the above-mentioned polymer binder, the same polymer binder as used in the heat-sensitive recording layer can be used. Further, from the viewpoint of preventing the reflection of light in the wavelength range that makes it difficult to see the image by reflecting from the surface of the support, and not deteriorating the transparency, the particle size of the fine particulate material is preferably 1 to 50 μm, and particularly 2 Organic or inorganic fine particles of -20 μm are preferred.

As a concrete example of such a fine particulate material,
Barley, wheat, corn, rice, other fine particles such as starch obtained from beans, cellulose fiber, polystyrene resin,
Examples thereof include epoxy resins, polyurethane resins, urea formalin resins, copolymer resins of vinyl chloride and vinyl acetate, fine particles of synthetic polymers such as polyolefin, and fine particles of inorganic substances such as calcium carbonate, titanium oxide and kaolin. Two or more kinds of these fine particulate materials may be used in combination.

The light reflection preventing layer has a surface shape measured by a scanning optical non-contact three-dimensional shape measuring machine (excluding undulation components of 100 μm or more) from the viewpoint of preventing light reflection to the extent that it does not become opaque. Surface roughness Ra of 0.15
It is preferably provided so as to have a thickness of 0.6 μm. The scanning optical non-contact 3D shape measuring machine is a highly accurate surface roughness measuring machine that can measure the 3D shape (roughness) of the surface in a non-contact manner using laser light, and the maximum resolution is measured. The range is ± 3 μm and 1.5 nm.

The antireflection layer in the present invention is a support prepared by dissolving or dispersing the above-mentioned polymer binder, fine particulate material and, if necessary, a surface active agent in water or an organic solvent, using a known coating means. It can be easily obtained by coating and drying on top. As the surfactant, the same ones as those used for the emulsion dispersion of the color developer can be appropriately selected and used.

Examples of the transparent support used in the present invention include polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate film, polyolefin films such as polystyrene film, polypropylene film and polyethylene film, and polyimide. Films, polyvinyl chloride films, polyvinylidene chloride films, polyacrylic films, polycarbonate films, and the like can be used, and these can be used alone or by laminating, but particularly polyester films that have been subjected to heat treatment and antistatic treatment. Is preferred. The thickness of the support is 10 μm to 200 μm.

In the present invention, in order to prevent the heat-sensitive recording layer and the light antireflection layer from peeling from the support, the heat sensitive layer and the light antireflection layer containing microcapsules are coated on the support before coating. It is desirable to provide an undercoat layer.
An acrylic ester copolymer, polyvinylidene chloride, SBR, an aqueous polyester, or the like can be used as the undercoat layer, and the film thickness is preferably 0.1 to 0.5 μm.

The undercoat layer may deteriorate the image recorded on the heat-sensitive layer if the undercoat layer swells due to the moisture contained in the heat-sensitive layer when the heat-sensitive layer is coated thereon. Glutaraldehyde, 2,3-dihydroxy-
It is desirable to cure using a dialdehyde such as 1,4-dioxane and a hardener such as boric acid. The amount of these hardeners added is in the range of 0.20% by weight to 3.0% by weight based on the weight of the undercoat material, and an appropriate amount can be selected according to the desired degree of curing.

The heat-sensitive layer, the protective layer, the undercoat layer and the like include blade coating method, air knife coating method, gravure coating method, roll coating coating method, spray coating method, dip coating method,
It is applied by a known application method such as a bar application method. The coating amount is preferably 1 to ²⁰ g / m ² , and particularly 3 to 10 g / m ^2.
It is preferably ² .

[0046]

As described above in detail, since the heat-sensitive recording material of the present invention has a layer for preventing light reflection on the surface of the transparent support on which an image is observed, a transmission image is observed through the support. In this case, the gloss is reduced and a transparent image with excellent image quality can be obtained.

[0047]

EXAMPLES The present invention will be described in more detail with reference to Examples below.
The present invention is not limited to this. In addition, "part" indicating the addition amount indicates "part by weight".

Example 1. Preparation of Capsule Liquid 2-anilino-3-methyl-6-N-ethyl-N-butylaminofluorane (leuco dye) 14 g and Takenate D-110N (trade name of capsule wall material manufactured by Takeda Pharmaceutical Co., Ltd.) 60 g , 1-phenyl-1-xylylethane (55 g) and ethyl acetate (55 g) were added to a mixed solvent and dissolved.

The obtained solution was added to 100 g of an aqueous solution of 8% by weight of polyvinyl alcohol (PVA217E: trade name of Kuraray Co., Ltd.), 40 g of water and 1.4 g of an aqueous sodium salt of dioctyl sulfosuccinate (dispersant) of 2% by weight. After mixing, emulsification was performed for 5 minutes at 10,000 rpm using an ace homogenizer (manufactured by Nippon Seiki Co., Ltd.). After further adding 150 g of water to the obtained emulsion, 4
Carry out encapsulation reaction at 0 ° C for 3 hours to obtain an average particle size of 0.7μ
m capsule liquid was prepared.

Preparation of color developer emulsified dispersion 8 g of color developer (a) represented by the following (Chemical formula 1),

[Chemical 1] 4 g of the developer (b) represented by the following (Chemical Formula 2),

[Chemical 2] And 30 g of a developer (c) represented by the following (Chemical Formula 3),

[Chemical 3] Was dissolved in a mixed solution of 8.0 g of 1-phenyl-1-xylylethane and 30 g of ethyl acetate.

The obtained solution was mixed with 100 g of an aqueous solution of 8% by weight of polyvinyl alcohol (PVA205: trade name of Kuraray Co., Ltd.), 150 g of water, and 0.5 g of sodium dodecylbenzenesulfonate, and then mixed with an ace homogenizer (Japan. (Made by Seiki Co., Ltd.)
The emulsion was emulsified at 00 rpm for 5 minutes at room temperature so that the average particle diameter was 0.5 μm to obtain an emulsified dispersion.

Preparation of heat-sensitive recording material 5.0 g of the above capsule liquid, 10.0 g of a color developer emulsion dispersion
A solution obtained by stirring and mixing 5.0 g of water and water was applied on a transparent polyethylene terephthalate (PET) support having a thickness of 70 μm so as to have a solid content of 15 g / m ² , and dried to form a heat-sensitive layer. . Next, a protective layer solution having the composition shown in Table 1 below was applied on the formed heat-sensitive layer to a thickness of 2 μm after drying.
A transparent heat-sensitive recording material was prepared by coating and drying so that the thickness became m.

[0053]

[Table 1] ───────────────────────────────────── Composition of protective layer liquid 10% by weight polyvinyl Alcohol (PVA124: trade name manufactured by Kuraray Co., Ltd.) 20 g Water 30 g 2% by weight Sodium salt of sulfosuccinodioctyl 0.3 g Polyvinyl alcohol (PVA205: trade name manufactured by Kuraray Co., Ltd.) 3 g, water 100 g and kaolin (calabrite: Kaolin dispersion in which 35 g of a product made by Thiele Kaolin Company) is dispersed in a ball mill 3 g Hydrin Z-7 (trade name of zinc stearate manufactured by Chukyo Yushi Co., Ltd.) 0.5 g ─────── ──────────────────────────────

[0054]

[Table 2] ─────────────────────────────────── Composition of the light reflection preventing layer liquid A 10% by weight Polyvinyl alcohol (PVA124: trade name manufactured by Kuraray Co., Ltd.) 20 g Water 30 g 2% by weight Sodium salt of sulfosuccindiooctyl 0.3 g Wheat starch (50% weight particle size is 14.5 μm) 0.1 g ──── ───────────────────────────────

The compositions shown in Table 2 above were stirred and mixed using a stirrer to obtain a light antireflection layer liquid. The obtained liquid was applied on the surface of the thermosensitive recording material opposite to the surface provided with the thermosensitive layer so that the solid content was 1 g / m ² and dried to provide a light reflection preventing layer. Using the obtained thermal recording material, an image was recorded using a thermal printer (FTI-1000: trade name manufactured by Fuji Photo Film Co., Ltd.), and the recorded image was observed as a transmission image using a Skarker Sten, It was a clear and good image with little gloss.

When the three-dimensional shape of the surface of the above heat-sensitive recording material on which the light reflection preventing layer was provided was measured by a non-contact three-dimensional roughness measuring machine, the surface roughness Ra was 0.4 μm. The measurement conditions were such that the diameter of the laser beam was 1 μm, the scan speed was 5 cm / min, and the measurement range was ± 30 μm.
A process of removing the waviness component of μm from the measured value was performed.

Example 2. The composition of Table 3 below was dispersed by a ball mill to obtain a particle size of 2.
A μm color developer dispersion was prepared.

[0058]

[Table 3] Dispersion ─────────────────────────────── Polyvinyl alur (PVA205: trade name of Kuraray Co., Ltd.) 5 g (Chemical Formula 4) 2 g developer (a)

[Chemical 4] 15 g of the developer (b) of (Chemical formula 5)

[Chemical 5] Water 100g ────────────────────────────────

9 g of the resulting developer dispersion, 5 g of the capsule liquid prepared in Example 1 and 5 g of water were stirred and mixed, and the mixture was solidified on a transparent polyethylene terephthalate (PET) support having a thickness of 70 μm. A heat-sensitive recording material was prepared in exactly the same manner as in Example 1 except that coating and drying were performed so that the amount became 15 g / m ² in minutes.

The obtained heat-sensitive recording material was coated with the antireflection layer liquid B having the composition shown in Table 4 below in exactly the same manner as in Example 1.
An image was recorded in the same manner as in Example 1 by drying and providing a light antireflection layer. The obtained image was a good reflection image with clear and little gloss. The surface roughness Ra was measured in the same manner as in Example 1 and found to be 0.31 μm.

[0061]

[Table 4] ─────────────────────────────────── Composition of the light reflection preventing layer liquid B 10% by weight Polyvinyl alcohol (PVA124: trade name manufactured by Kuraray Co., Ltd.) 20 g Water 30 g 2% by weight Sodium salt of sulfosuccindiooctyl 0.3 g Rice starch (50% weight particle size is 7.5 μm) 0.1 g ──── ───────────────────────────────

Example 3. Preparation of capsule liquid Compound of the following (Chemical formula 6)

[Chemical 6] In 50 parts, 150 g of methylene chloride, 50 parts of tricresyl phosphate, 150 parts of trimethylolpropane trimethacrylate and 75% by weight of trimethylolpropane 3: 1 adduct of m-xylylene diisocyanate.
200 parts of an ethyl acetate solution (Takenate D110N: trade name of Takeda Pharmaceutical Co., Ltd.) was uniformly mixed to obtain an oil phase solution.

On the other hand, 7% by weight of polyvinyl alcohol (PVA217E: 88 to 89% of degree of fighting, degree of polymerization of 1,
700: 600 parts of Kuraray Co., Ltd.) was prepared to obtain a water-soluble polymer aqueous solution.

Then, the dissolver was attached to a 5 liter stainless steel pot equipped with a warm bath, the polymer aqueous solution was added thereto, and then the oil phase solution was added while stirring the dissolver so that the emulsion had an average particle size of Emulsification and dispersion were carried out while observing with a microscope so that the thickness became about 1.5 μm. After the dispersion was completed, the stirring was slowed down, and warm water of 42 ° C. was passed through the warm bath, the temperature in the pot was kept at 40 ° C., and the encapsulation reaction was completed in 3 hours. Ion exchange resin MB-3 was added to the obtained liquid.
(Organic Co., Ltd. product name) 25 ml was added and stirred, and then filtered to obtain a capsule liquid.

Preparation of Dispersion A The substances shown in Table 5 below were mixed and pre-dispersed with a dissolver, followed by averaging with Dyno-Mill (WILLY A. BACHOFEN AG). Diameter 2
Dispersion A was obtained by dispersing so as to have a particle size of μm.

[0066]

[Table 5] ────────────────────────────────────   15 wt% polyvinyl alcohol aqueous solution (PVA-205: manufactured by Kuraray Co., Ltd. Brand name) 30 copies   Coupler of the compound of Chemical formula 7 4.3 parts

[Chemical 7] 0.6 part of the coupler of the compound of Chemical formula 8

[Chemical 8] 5.0 parts of the organic basic compound of Chemical formula 9

[Chemical 9] 3.0 parts of the color forming improver of (Chemical Formula 10)

[Chemical 10] ────────────────────────────────────

Preparation of Dispersion B The materials shown in Table 6 below were mixed and stirred to obtain Dispersion B.

[Table 6] ────────────────────────────────────   Univer 70 (product name of Shiraishi Industry Co., Ltd.) 20 copies Product name of Kaobright (Thiele Kaolin Company) ) ─── 40 parts by weight sodium hexametaphosphate aqueous solution 0.5 part 30 parts of water ────────────────────────────────────

Preparation of Thermosensitive Recording Material 20 parts of the above-mentioned capsule liquid, 20 parts of dispersion liquid A, 7 parts of dispersion liquid B and 1.5 parts of 2% by weight aqueous solution of Nissan Lapizole 13-90 (trade name of NOF CORPORATION) were stirred. Mix and
70 μm thick polyethylene terephthalate (PET)
On the support so that the solid content is 15 g / m ^2.
It was dried to provide a heat sensitive layer. Further, a mixture having the composition shown in Table 7 below was applied on the heat-sensitive layer so as to have a thickness of 2 μm to provide a protective layer, to prepare a heat-sensitive recording material.

[0069]

[Table 7]   Composition of protective layer ─────────────────────────────────── 10 wt% polyvinyl alcohol (PVA124: Kuraray Co., Ltd. product name)                                                               20 g 30 g of water 2% by weight sodium salt of dioctyl sulfosuccinate 0.3 g Polyvinyl alcohol (PVA205: Kuraray Co., Ltd. product name) 3 g, water 10 0g and kaolin (Kahbright: Thiele K Kaolin in which 35 g of trade name) manufactured by Olin Company) is dispersed by a ball mill Dispersion 3g Hydrin Z-7 (trade name of Chukyo Yushi Co., Ltd.) 0.5 g ────────────────────────────────────

The obtained heat-sensitive recording material was coated and dried with a light reflection preventing layer liquid C having the composition shown in Table 8 in the same manner as in Example 1 to form a light reflection preventing layer, and in the same manner as in Example 1. The image was recorded. The obtained image was a good reflection image with clear and little gloss. Further, the surface roughness Ra was measured in the same manner as in Example 1 and found to be 0.45 μm.

[0071]

[Table 8] ─────────────────────────────────── Composition of the light reflection preventing layer liquid C 10% by weight Polyvinyl alcohol (PVA124: trade name manufactured by Kuraray Co., Ltd.) 20 g water 30 g 2 wt% sodium salt of dioctyl sulfosuccinate 0.3 g calcium bicarbonate (Whiten H: trade name manufactured by Shiroishi Industry Co., Ltd.) 0.1 g ── ──────────────────────────────────

Comparative Example 1. An image was recorded in the same manner as in Example 1 using the same heat-sensitive recording material as in Example 1 except that the light reflection preventing layer was not provided. The obtained image was clear but had a high gloss. However, the transmission image was inferior in appearance. still,
When the surface roughness Ra was measured in exactly the same manner as in Example 1, it was 0.1 μm.

Comparative Example 2. A heat-sensitive recording material was prepared in exactly the same manner as in Example 1 except that the light antireflection layer liquid used in Example 1 was replaced with the light antireflection layer liquid having the composition shown in Table 9 below. When an image was recorded in exactly the same manner, the obtained image had little gloss, but it was faint and unclear. The surface roughness Ra was measured in the same manner as in Example 1 and found to be 0.
It was 7 μm.

[0074]

[Table 9] ─────────────────────────────────── Composition of the light reflection preventing layer liquid C 10% by weight Polyvinyl alcohol (PVA124: trade name of Kuraray Co., Ltd.) 20 g Water 30 g 2% by weight Dioctyl sulfosuccinate sodium salt 0.3 g Wheat starch (50% weight particle size 14.5 μm) 0.5 g Polyvinyl alcohol (PVA205: Kuraray stock) Kaolin dispersion in which 3g of company-made trade name), 100g of water and 35g of kaolin (trade name of Kabright: Thiele Kolin Company) are dispersed in a ball mill 3g ───────────── ──────────────────────────

Claims (2)

[Claims] 1. A heat-sensitive recording material for observing a recorded image from a transparent support side, wherein a heat-sensitive recording layer is provided on one surface of the transparent support and a layer for preventing light reflection is provided on the other surface. A thermosensitive recording material characterized by being provided. 2. The surface roughness Ra of the surface of the layer for preventing light reflection measured by a scanning optical non-contact three-dimensional shape measuring machine by removing a waviness component of 100 μm or more is 0.15.
The heat-sensitive recording material according to claim 1, wherein the heat-sensitive recording material is about 0.6 μm.