JPH08267930A - Thermal recording material - Google Patents

Abstract

PURPOSE: To obtain a thermal recording material forming a developed color image excellent in stability and having sufficient thermal sensitivity characteristics by using a fluorine-containing bisphenol compd. represented by a specific formula as a coupler. CONSTITUTION: In a thermal recording material wherein a thermal color forming layer containing a lueco dye and a coupler is provided on a support, a fluorine- containing bisphenol compd. represented by formula (wherein R is 1-3C alkyl group and X is a hydrogen atom or a fluorine atom) is used as the coupler. By using the coupler and providing an intermediate layer containing plastic spherical fine hollow particles composed of a thermoplastic resin between the support and the thermal color forming layer, a more excellent thermal recording material is obtained. By this constitution, a thermal recording material forming a developed color image excellent in stability and having sufficient thermal sensitivity characteristics is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in the fields of computer output, printers such as calculators, recorders for medical measurement, low speed and high speed facsimile fields, automatic ticket vending machines, heat sensitive copying fields, POS system label fields, etc. The present invention relates to a widely used heat sensitive recording material.

[0002]

2. Description of the Related Art A heat-sensitive recording material utilizing a heat-coloring reaction of a normally colorless or light-coloring dye (leuco dye) with phenols, organic acids, etc. is disclosed in JP-B-43-4160 and JP-B-45-14039. , Japanese Patent Laid-Open No. 48-27736, and has been widely put into practical use. Generally, a heat-sensitive recording sheet is prepared by pulverizing and dispersing a leuco dye and a color developing agent such as a phenolic substance into fine particles, respectively, and then mixing them together to obtain a binder, a filler, a sensitivity improver, a lubricant, and other auxiliaries. The coating solution obtained by adding is applied to a support such as paper and film, and color recording is obtained by an instantaneous chemical reaction by heating. A thermal printer, a facsimile, or the like having a built-in thermal head is used for heating the heat-sensitive recording material to develop color. Further, such a recording material can obtain a recording in a relatively short time, does not generate noise, and is relatively free from complicated processing such as development and fixing as compared with other recording materials. Due to the advantages of being inexpensive, not only copying books, documents, etc.
It is widely used as a recording material for information such as facsimiles, telex, medical measuring instruments, and measuring instruments. However, in recent years, there has been a strong demand for high-speed recording with the development of society. Therefore, it has been strongly desired to increase the speed of the recording apparatus itself and to develop a recording material that can cope with this. Conventionally, such thermal recording sheets for high speed recording have been disclosed in JP-A-53-39139 and JP-A-53-26139.
Japanese Patent Laid-Open No. 53-5636, Japanese Patent Laid-Open No. 53-1
As disclosed in 1036, various waxes, fatty acid amides, alkylated biphenyls, substituted biphenyl alkalis, coumarin compounds, diphenylamines, and other low-melting-point heat-melting substances are used as sensitizers or melting point depressants. Those added to the thermosensitive coloring layer have been proposed. In the method of adding this sensitizer, it is necessary to melt the sensitizer first before the color development reaction. , The fusible substance in the color development layer melts, so the thermal head residue sticks, bleeds, and trails,
It has a drawback that troubles such as ghosts are likely to occur, and the background color often develops (fog) even under storage conditions at high temperature or high humidity, and the contrast of recorded images often deteriorates. Therefore, a heat-sensitive recording sheet for high-speed recording having a constitution in which such a sensitizer or a melting point depressant is not added is preferable, but a color-forming colorless dye having a structure such as lactone, lactam or spiropyran used for the heat-sensitive recording sheet is preferable. Since the melting point is usually as high as 160 to 240 ° C., in order to obtain a heat-sensitive recording sheet suitable for high speed recording without adding a sensitizer or a melting point depressant, a colorless dye having a low melting point as a developer is developed. High potency phenolic materials have been used. Regarding the phenol color developing agent, many substances are described in various documents including Japanese Patent Publication No. 45-14039, and among them, 2,2-bis (4′-hydroxyphenyl) propane (bisphenol A melting point 156-158
℃) is often used in terms of quality stability, price, and availability. However, this bisphenol A has a defect that the thermal color development temperature is high. On the other hand, a phenolic substance having a low melting point, for example, 4-tert-butylphenol (melting point 94 to 99 ° C.), α-naphthol (melting point 9
5 to 96 ° C.), β-naphthol (melting point 119 to 122
When a monophenol such as (.degree. C.) is used, the heat-sensitive recording sheet has poor storability and stability, and the background color gradually develops even at room temperature, and a so-called phenol odor is strong and not practical. Also, in Japanese Patent Publication No. 54-12519, 2,2-bis (4'-hydroxyphenyl) normal hexane (melting point 99 to 103 ° C) is disclosed in JP-A-55-55.
No. 27253 discloses that a 1,1-bis (4'-hydroxyphenyl) alkane (alkane having 3 to 13 carbon atoms) has a low melting point, and a thermosensitive recording sheet having good stability and color development can be produced. However, these substances are difficult to synthesize and have problems in availability. Furthermore, JP-A-56-14
Japanese Patent No. 4193 describes that a lower alkyl ester or a benzyl ester, which is expected to be p-hydroxybenzoate, can be easily synthesized and a high-sensitivity thermal recording sheet can be produced. However, it has a drawback that crystals of the phenolic substance are deposited on the color-developed part (so-called white powder phenomenon). As described above, among the practically industrially usable developers, almost no one has been found in which the color image at high-speed recording is clear and has a high temperature, and the color image has stable characteristics. is there.

[0003]

DISCLOSURE OF THE INVENTION The present invention overcomes the drawbacks found in the prior art and is excellent in the stability of a color image,
Moreover, it is an object of the present invention to provide a heat-sensitive recording material having sufficient heat sensitivity characteristics.

[0004]

According to the present invention, a thermosensitive recording material comprising a support and a thermosensitive coloring layer containing a leuco dye and a developer is provided on the support as the developer represented by the following general formula: This is solved by using the fluorine-containing bisphenol compound represented by I).

Embedded image (In the formula, R represents an alkylene group having 1 to 3 carbon atoms, and X represents a hydrogen atom or a fluorine atom)

Examples of the fluorine-containing bisphenol compound represented by the above general formula (I) include, but are not limited to, the compounds shown in Table 1 below.

[0006]

[Table 1]

Further, by using the developer and providing an intermediate layer containing plastic spherical fine hollow particles made of a thermoplastic resin between the support and the thermosensitive coloring layer, a more excellent thermosensitive recording material can be obtained. Provided.

The intermediate layer containing the plastic spherical hollow particles of the present invention as a main component acts as a heat insulating layer to improve the sensitivity by efficiently utilizing the heat energy from the thermal head and the like, and further, the average particle diameter of the plastic hollow particles. Is 2
When the hollowness is -10 μm and the hollow ratio is 90% or more, the flexibility is further improved, the adhesion with the head is improved, and the dot reproducibility is improved.

The hollow particles used in the heat-sensitive recording material of the present invention (hereinafter, also simply referred to as recording material) have a thermoplastic resin as a shell and contain air or other gas inside, and are already in a foamed state. Fine hollow particles having an average particle size of 2 to 10 μm, more preferably
It is preferably 3 to 6 μm. This average particle diameter (particle outer diameter)
If it is less than 2 μm, there is a production problem such as it is difficult to make it to an arbitrary hollow ratio. On the other hand, if it is more than 10 μm, the smoothness of the surface after coating and drying is deteriorated, so that the thermal head Adhesion is reduced, and sensitivity improving effect is reduced. Therefore, such a particle distribution preferably has a particle diameter within the above range and a uniform particle diameter with a distribution peak with little variation. Furthermore, the hollow microparticles used in the present invention preferably have a hollowness of 50% or more, and particularly preferably 90% or more, due to their heat insulating effect. If the hollowness is low, the heat insulating effect is insufficient, so that heat energy from the thermal head is released to the outside of the heat-sensitive recording material through the support, resulting in poor sensitivity improving effect. The hollow ratio mentioned here is the ratio of the outer diameter to the inner diameter of the hollow particles and is represented by the following formula. Hollow ratio = A / B × 100 (%) A: Inner diameter of hollow particles B: Outer diameter of hollow particles The fine hollow particles used in the present invention have a thermoplastic resin shell as described above. Examples of the resin include copolymer resins mainly containing vinylidene chloride and acrylonitrile, polyolefin resins such as polyethylene, polypropylene, ethylene / propylene copolymer, polyester, polyamide (nylon), acrylic resin, ABS. Examples thereof include resins, MBS resins, vinyl chloride resins, and styrene / acrylic copolymers. Among these resins, vinylidene chloride is particularly preferable in terms of ease of production such as uniformity of particle diameter of hollow particles. And a copolymer resin mainly composed of acrylonitrile is preferable.

In the present invention, an inorganic or / and organic pigment is optionally used in the intermediate layer. In this case, the amount of oil supplied is 30 ml / 100 g or more, preferably 8
Items of 0ml / 100g or more are selected. These inorganic or /
As the organic pigment, one kind or two or more kinds of pigments commonly used for this kind of heat-sensitive recording material can be selected. Specific examples thereof include calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, talc, inorganic pigments such as surface-treated calcium and silica, and urea-formalin resin. Examples thereof include organic pigments such as styrene / methacrylic acid copolymer and polystyrene resin. The content of the inorganic or / and organic pigment in the intermediate layer is 0 to 50% by weight,
It is preferably 0 to 20% by weight.

The leuco dyes used in the present invention may be applied alone or as a mixture of two or more kinds, and as such leuco dyes, any one applied to the recording material of this kind may be optionally applied, for example, a trio dye. Phenylmethanephthalide type, triallylmethane type, fluorane type, phenothidian type, thiofluorane type, xanthene type, indophthalyl type, spiropyran type, azaphthalide type, chromenopyrazole type, methine type, rhodamine anilinolactam type,
Leuco compounds such as rhodamine lactam type, quinazoline type, diazaxanthene type and bislactone type are preferably used. Examples of such compounds include those shown below.

3,3-bis (p-dimethylaminophenyl) -phthalide, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-diethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-chlorophthalide, 3,3-bis (p-dibutylaminophenyl) phthalide, 3-cyclohexylamino-6-chlorofluorane, 3-dimethylamino-
5,7-Dimethylfluorane, 3- (N-methyl-N-
Isoamylamino) -6-methyl-7-anilinofluorane, 3- (N-ethyl-N-isobutylamino) -6
-Methyl-7-anilinofluorane, 3- (Np-tolyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3- (N-methyl-N-amylamino)-
6-methyl-7-anilinofluorane, 3- (N, N-
Di-n-amylamino) -6-methyl-7-anilinofluorane, 3- (N-methyl-N-cyclohexylamino) -6-methyl-7-anilinofluorane, 3- (N
-Methyl-N-iso-propylamino) -6-methyl-7-anilinofluorane, 3- (N-ethyl-N-tetrahydrofurylamino) -6-methyl-7-anilinofluorane, 3-diethylamino -7,8-benzfluorane, 3-diethylamino-7-chlorofluorane,
3-diethylamino-7-methylfluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-
Pyrrolidino-6-methyl-7-anilinofluorane, 3
-Diethylamino-6-methyl-7- (m-trichloromethylanilino) fluorane, 3-diethylamino-7
-(O-chloroanilino) fluorane, 3-dibutylamino-7- (o-chloroanilino) fluorane, 3-diethylamino-6-methyl-7-anilinofluorane,
3-dibutylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7- (2 ',
4'-dimethylanilino) fluorane, 3- (N, N-
Diethylamino) -5-methyl-7- (N, N-dibenzylamino) fluorane, benzoylleuco methylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrrilospirane, 6'-bromo-3'-methoxy-
Benzindolino-pyrrilospirane, 3- (2'-hydroxy-4'-dimethylaminophenyl) -3- (2 '
-Methoxy-5'-chlorophenyl) phthalide, 3-
(2'-hydroxy-4'-dimethylaminophenyl)
-3- (2'-methoxy-5'-nitrophenyl) phthalide, 3- (2'-hydroxy-4'-diethylaminophenyl) -3- (2'-methoxy-5'-methylphenyl) phthalide, 3- (2'-Methoxy-4'-dimethylaminophenyl) -3- (2'-hydroxy-4'-
Chlor-5'-methylphenyl) phthalide, 3-morpholino-7- (N-propyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7-trifluoromethylanilinofluorane, 3-diethylamino-5-chloro. -7- (N-benzyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7- (di-p-chlorophenyl) methylaminofluorane, 3-diethylamino-5-chloro-7- (α-phenylethylamino) )
Fluoran, 3- (N-ethyl-p-toluidino) -7
-(Α-phenylethylamino) fluorane, 3-diethylamino-7- (o-methoxycarbonylphenylamino) fluorane, 3-diethylamino-5-methyl-
7- (α-phenylethylamino) fluorane, 3-diethylamino-7-piperidinoaminofluorane, 2-
Chloro-3- (N-methyltoluidino) -7- (p-N
-Butylanilino) fluorane, 3,6-bis (dimethylamino) fluorene spiro (9,3 ')-6'-dimethylaminophthalide, 3- (N-benzyl-N-cyclohexylamino) -5,6-benzo- 7-α-naphthylamino-4′-bromofluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3- (N-ethyl-N-2-ethoxypropylamino) -6-methyl-7 -Anilinofluorane, 3- (N-ethyl-N-tetrafurfurylamino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-mesitidino-4 ', 5'- Benzofluorane, 3- (p-dimethylaminophenyl) -3- {1,1-bis (p-dimethylaminophenyl) ethylene-2-yl} phthalide, 3- (p-dimethyl Minofeniru) -3- {1,
1-bis (p-dimethylaminophenyl) ethylene-2
-Yl} -6-dimethylaminophthalide, 3- (p-dimethylaminophenyl) -3- (1-p-dimethylaminophenyl-1-phenylethylene-2-yl) phthalide, 3- (p-dimethylamino) Phenyl) -3- (1-
p-dimethylaminophenyl-1-p-chlorophenylethylene-2-yl) -6-dimethylaminophthalide,
3- (4'-dimethylamino-2'-methoxy) -3-
(1-p-Dimethylaminophenyl-1-p-chlorophenyl-1,3-butadiene-4-yl) benzophthalide, 3- (4'-dimethylamino-2'-benzyloxy) -3- (1-p- Dimethylaminophenyl-1-phenyl-1,3-butadiene-4
-Yl) benzophthalide 3-dimethylamino-6-dimethylamino-fluorene-9-spiro-3 '-(6'-dimethylamino) phthalide, 3,3-bis {2- (p-dimethylaminophenyl) -2- (P-Methoxyphenyl) ethenyl} -4,
5,6,7-Tetrachlorophthalide, 3-bis {1,1
-Bis (4-pyrrolidinophenyl) ethylene-2-yl} -5,6-dichloro-4,7-dibromophthalide,
Bis (p-dimethylaminostyryl) -1-naphthalenesulfonylmethane, bis (p-dimethylaminostyryl) -1-p-tolylsulfonylmethane and the like.

In order to produce the heat-sensitive recording material of the present invention, a leuco dye, the compound of the present invention as a developer and other auxiliary agents may be supported and bound on a support. As the binder in this case, various conventional binders can be used in appropriate amounts, and specific examples thereof include the following. Polyvinyl alcohol, starch and its derivatives, methoxy cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose,
Cellulose derivatives such as ethyl cellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylamide / acrylic acid ester copolymer, acrylamide / acrylic acid ester / methacrylic acid terpolymer, styrene /
Maleic anhydride copolymer alkali salt, isobutylene / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein and other water-soluble polymers, as well as polyvinyl acetate, polyurethane, polyacrylic ester, poly Methacrylic acid ester, vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer emulsion, styrene / butadiene / acrylic copolymer latex and the like.

In the present invention, various heat-fusible substances may be used in combination as the sensitivity improver, and specific examples thereof include the followings, but the present invention is not limited thereto. Fatty acids such as stearic acid and behenic acid, fatty acid amides such as stearic acid amide and palmitic acid amide, fatty acid metal salts such as fatty acids such as zinc stearate, aluminum stearate, calcium stearate, zinc palmitate and zinc behenate, p-benzylbiphenyl, terphenyl, triphenylmethane, p
-Benzyl benzyloxybenzoate, β-benzyloxynaphthalene, phenyl β-naphthoate, phenyl 1-hydroxy-2-naphthoate, methyl 1-hydroxy-2-naphthoate, diphenyl carbonate, glare coal carbonate, dibenzyl terephthalate , Dimethyl terephthalate, 1,4-dimethoxynaphthalene, 1,4-
Diethoxynaphthalene, 1,4-dibenzyloxynaphthalene, 1,2-diphenoxyethane, 1,2-bis (3
-Methylphenoxy) ethane, 1,2-bis (4-methylphenoxy) ethane, 1,4-diphenoxybutane,
1,4-Cyphenoxy-2-butene, 1,2-bis (4-
Methoxyphenylthio) ethane, dibenzoylmethane,
1,4-diphenylthiobutane, 1,4-diphenylthio-2-butene, 1,3-bis (2-vinyloxyethoxy) benzene, 1,4-bis (2-vinyloxyethoxy) benzene, p- ( 2-vinyloxyethoxy) biphenyl, p-aryloxybiphenyl, p-propargyloxybiphenyl, dibenzoyloxymethane, dibenzoyloxypropane, dibenzyldisulfide,
1,1-diphenylethanol, 1,1-diphenylpropanol, p-benzyloxybenzyl alcohol,
1,3-phenoxy-2-propanol, N-octadecylcarbamoyl-p-methoxycarbonylbenzene,
N-octadecylcarbamoylbenzene, 1,2-bis (4-methoxyphenoxy) propane, 1,5- (4-
Methoxyphenoxy) -3-oxapentane, dibenzyl oxalate, bis (4-methylbenzyl) oxalate, bis (4-chlorobenzyl) oxalate and the like.

In the case of obtaining a heat-sensitive recording material according to the present invention, a leuco dye, a color developer, the compound of the present invention and, if necessary, an additive component commonly used in this kind of heat-sensitive recording material, such as a filler or a surface active agent. Agents, lubricants, pressure color-developing inhibitors, etc. can be used in combination. In this case, as the filler, for example, calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, kaolin, talc, inorganic fine powder such as surface-treated calcium or silica, and urea. -Organic fine powders such as formalin resin, styrene / methacrylic acid copolymer, polystyrene resin and vinylidene chloride resin can be mentioned. As the lubricant, higher fatty acid and its metal salt, higher fatty acid amide, higher fatty acid ester can be used. , Various animal, vegetable, mineral or petroleum waxes.

In the present invention, a layer containing a pigment, a binder, a heat-fusible substance and the like can be provided as another intermediate layer between the intermediate layer and the thermosensitive coloring layer, if necessary. Furthermore, the recording material of the present invention may be provided with a protective layer on the heat-sensitive recording layer for the purpose of improving the storage stability of a recorded image or improving the writing property on the recording material. As the constituents of the protective layer, the above-mentioned pigments, binders, heat-fusible substances and the like can be used. As the support used in the present invention, various materials having a solid surface are used. As such,
Examples thereof include paper, synthetic paper, plastic film, and a laminate of plastic film and paper.

Further, for the purpose of improving the storage stability of recorded images, various compounds having an electron accepting property as other developers in the thermosensitive color developing layer, such as phenolic compounds, thiophenolic compounds and thiourea. Derivatives, organic acids, metal salts thereof, and the like can be used, and specific examples thereof include, but are not limited to, those shown below. Further, the use ratio of these other developers and the developers used in the present invention is preferably 5: 1 to 0: 1 by weight.

4,4'-isopropylidene diphenol, 4,4'-isopropylidene bis-o-methylphenol, 4,4'-sec-butylidene bisphenol, 4,4 'isopropylidene bis (2-tert-) Butylphenol), zinc p-nitrobenzoate, 1,3
5-tris (4-tert-butyl-3-hydroxy-
2,6-dimethylbenzyl isocyanuric acid, 2,2-
(3,4′-dihydroxyphenyl) propane, bis (4-hydroxy-3-methylphenyl) sulfide,
4- [β- (p-methoxyphenoxy) ethoxy] salicylic acid, 1,7-bis (4-hydroxyphenylthio)
-3,5-Dioxaheptane, 1,5-bis (4-hydroxyphenylthio) -3-oxapentane, phthalic acid monobenzyl ester monocalcium salt, 4,4'-cyclohexidenediphenol, 4,4 ' -Isopropylidenebis (2-chlorophenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 4,4'-butylidenebis (6-tert-butyl-2-methylphenol), 1, 1,3-Tris (2
-Methyl-4-hydroxy-5cyclohexylphenyl) butane, 4,4'-thiobis (6-tert-butyl-2-methylphenol), 4,4'-diphenolsulfone, 4-isopropoxy-4'-hydroxy Diphenyl sulfone, 4-benzyloxy-4'-hydroxydiphenyl sulfone, 4,4'-ciphenol sulfoxide, isopropyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, benzyl protocatechuate,
Stearyl gallate, lauryl gallate, octyl gallate, 1,3-bis (4-hydroxyphenylthio) propane, N, N'-diphenylthiourea, N, N'-di (m-chlorophenyl) thiourea, salicyl Anilid,
Methyl bis- (4-hydroxyphenyl) acetate, benzyl bis (4-hydroxyphenyl) acetate, 1,3-bis (4-hydroxyphenyl) benzene, 1,4-bis (4-hydroxyphenyl) benzene, 2,4 ′ -Diphenol sulfone, 2,2′-diallyl-4,4′-hydroxyphenyl sulfone, 3,4-dihydroxy-4
′ -Methyldiphenyl sulfone, 1-acetyloxy-
Zinc 2-naphthoate, zinc 2-acetyloxy-3-naphthoate, zinc 2-acetyloxy-1-naphthoate,
α, α-bis (4-hydroxyphenyl) -α-methyltoluene, antipyrine complex of zinc thiocyanate, tetrabromobisphenol A, tetrabromobisphenol S, 4,4′-thiobis (2-methylphenol),
4,4'-thiobis (2-chlorophenol) and the like.

[0019]

EXAMPLES The present invention will now be described in more detail with reference to Examples. All parts and% shown below are based on weight.

Example 1 The following mixture was pulverized and dispersed in a magnetic ball mill for 2 days to prepare [solution A] [solution B] [solution C]. [Liquid A] 3- (N-methyl-N-cyclohexyl) amino-6-methyl-7-anilinofluorane 20 parts 10% aqueous solution of polyvinyl alcohol 20 parts Water 60 parts [Liquid B] 4,4'-methylenebis (2-Fluorophenol) 20 parts [Specific example of general formula (I) No. Compound of 1] 10% aqueous solution of polyvinyl alcohol 20 parts Water 60 parts [C liquid] Calcium carbonate 20 parts Methylcellulose 20 parts Water 60 parts [A liquid] 10 parts, [B liquid] 30 parts, [C liquid] 40 And 10 parts of zinc stearate dispersion (trade name: Hydrin Z-730, 30% concentration, manufactured by Chukyo Yushi Co., Ltd.) are mixed to form a thermosensitive color forming layer liquid, which is the surface of commercially available high-quality paper (basis weight 52 g / m2). After coating and drying so that the amount of adhesion after drying is 0.5 g / m2 and providing a thermosensitive coloring layer, the layer surface is calendered so that the surface smoothness is 500 to 600 seconds. A recording material (a) was produced.

Example 2 A thermosensitive recording material (b) was prepared in the same manner as in Example 1 except that the following [Solution D] was used instead of [Solution B] in Example 1. [Liquid D] 4,4′-methylenebis (2,6-difluorophenol) 20 parts [Specific Example No. of General Formula (I)] Compound of 2] 10% aqueous solution of polyvinyl alcohol 20 parts water 60 parts

Example 3 A thermosensitive recording material (c) was prepared in the same manner as in Example 1 except that the following [Solution E] was used instead of [Solution B] in Example 1. [Liquid E] 4,4′-isopropylidene bis (2-fluorophenol) 20 parts [Specific Example No. Compound of 5] 10% aqueous solution of polyvinyl alcohol 20 parts water 60 parts

Example 4 The following mixture was stirred and dispersed to obtain an intermediate layer forming liquid [F liquid]. [F liquid] Micro hollow particle dispersion (HP-91 manufactured by Rohm and Haas Co .; copolymer resin mainly composed of styrene and acryl, 30 parts, solid content concentration 38%, average particle diameter 0.7 μm, hollow ratio 80%) Styrene / butadiene copolymer latex (concentration of solid content 47.5%) 10 parts Water 60 parts The above intermediate layer forming liquid has a weight of 5 g / m2 after drying on the surface of commercially available high-quality paper (basis weight 52 g / m2). Thus coated and dried to obtain an intermediate coated paper. Next, the thermosensitive color forming layer-forming liquid obtained in Example 1 was applied and dried on the intermediate layer so that the amount of dye adhering after drying was 0.5 g / m @ 2 to form a thermosensitive color forming layer, and then the surface was smoothed. A thermal recording material (d) was prepared by calendering the layer surface so that the degree was 500 to 600 seconds.

Example 5 A thermosensitive recording material (e) was prepared in the same manner as in Example 4, except that the thermosensitive coloring layer forming liquid used in Example 2 was used.

Example 6 A thermosensitive recording material (f) was prepared in the same manner as in Example 4 except that the thermosensitive color developing layer forming liquid used in Example 3 was used.

Comparative Example 1 A thermosensitive recording material (g) was prepared in the same manner as in Example 1 except that the following [Solution G] was used instead of [Solution B] in Example 1. [G liquid] Bisphenol A 20 parts 10% aqueous solution of polyvinyl alcohol 20 parts Water 60 parts

Comparative Example 2 A thermosensitive recording material (h) was prepared in the same manner as in Example 3 except that the thermosensitive color developing layer forming liquid used in Comparative Example 1 was used.

Comparative Example 3 A thermosensitive recording material (i) was prepared in the same manner as in Example 1 except that the following [Solution H] was used instead of [Solution B] in Example 1. [H liquid] p-hydroxybenzoic acid benzyl ester 20 parts 10% aqueous solution of polyvinyl alcohol 20 parts water 60 parts

Comparative Example 4 A thermosensitive recording material (j) was prepared in the same manner as in Example 4 except that the thermosensitive color developing layer forming liquid used in Comparative Example 3 was used.

The thermal recording materials (a) to (j) produced as described above are printed at high speed (printing speed: 0.94 m) by a G-III prototype facsimile machine (manufactured by Ricoh Co., Ltd.).
sec, applied voltage: 16 V, 18 V, 20 V), and the color density was measured with a Macbeth densitometer RD-514.
Further, the white powder phenomenon in the color-developed portion was examined when the printed sample was left in the room for 3 days. The results are shown in Table 2.

[0031]

[Table 2]

[0032]

The heat-sensitive recording material of the present invention is excellent in color developability during high-speed recording, has no white powder phenomenon, and has extremely stable images.

Claims (2)

[Claims] 1. A heat-sensitive recording material comprising a support and a heat-sensitive coloring layer containing a leuco dye and a developer, the fluorine-containing bisphenol compound represented by the following general formula (I) being used as the developer. A thermosensitive recording material characterized by being used. Embedded image (In the formula, R represents an alkylene group having 1 to 3 carbon atoms, and X represents a hydrogen atom or a fluorine atom) 2. A thermosensitive recording comprising an intermediate layer containing plastic spherical micro hollow particles made of a thermoplastic resin on a support, and a thermosensitive coloring layer containing a leuco dye and a color developer provided on the intermediate layer. In the material, a fluorine-containing bisphenol compound represented by the general formula (I) is used as the developer, a heat-sensitive recording material.