JPH07186528A - Thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a thermal recording material of good quality having high sensitivity and good raw preservability and forming a developed color image good in stability by adding an N-substituted anthranilic acid derivative or a metal salt thereof to a thermal color forming layer. CONSTITUTION:An a thermal recording material wherein a thermal color forming layer containing an electron donating leuco dye and an electron acceptive compd. is provided on a support, an N-substituted anthanilic acid derivative represented by either one of general formulae I, II (wherein R1 is a hydrogen atom, an alkyl group or an aryl group, R2 is an alkyl group, a cycloalkyl group, an aryl group, an alkylamino group, an alkyloxy group, an aryloxy group or an arylamino group, X is an oxygen atom or a sulfur atom, M is an n-valent metal atom and n is an integer) or a metal salt thereof is added to the thermal color forming layer. By this constitution, the thermal recording material of good quality having high sensitive, good raw preservability and forming a developed color image good in stability is obtained.

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 improved color developability, raw storability and stability of color image.

[0002]

2. Description of the Related Art Recording materials using an electron-donating colorless dye and an electron-accepting compound are pressure-sensitive paper, thermal paper, photosensitive pressure-sensitive paper,
It is already well known as an electrically conductive recording paper and a thermal transfer paper. For example, British Patent No. 2,140,449, US Patent Nos. 4,480,052, and 4,436,920.
Japanese Patent Publication No. 60-23992, JP-A No. 57-1798.
No. 36, No. 60-123556, No. 60-12355.
Details on No. 7 etc. In particular, the thermal recording material is
For details, see No. 4160 and Japanese Patent Publication No. 45-14039. These thermal recording systems are applied to various fields such as facsimiles, printers and labels, and their needs are expanding. However, since the heat-sensitive recording material has a defect that fog is caused by a solvent and the like, and a color developing body is discolored by oils and fats, chemicals, etc., labels, slips, word processor papers, plotters, etc. In the field of paper and the like, the commercial value has been significantly impaired. The inventors of the present invention have found that the electron-donating colorless dye and the electron-accepting compound each have oil solubility, water solubility, partition coefficient, p
Focusing on Ka, the polarity of the substituents, and the positions of the substituents, we have pursued the development of good recording material materials and recording materials.
However, the addition of these resistances has caused a problem that the sensitivity is significantly lowered.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-sensitive recording material of high print quality, which has high sensitivity, good raw storability, and good stability of color image.

[0004]

SUMMARY OF THE INVENTION The problem to be solved by the present invention is to provide a thermosensitive recording material having a thermosensitive coloring layer containing an electron-donating colorless dye and an electron-accepting compound on a support. The following general formula (I) or (I
It was achieved by a heat-sensitive recording material containing an N-substituted anthranilic acid derivative represented by I) or a metal salt thereof.

[0005]

[Chemical 4]

[0006]

[Chemical 5]

In the above formula, R ₁ is a hydrogen atom, an alkyl group or an aryl group, R ₂ is an alkyl group, a cycloalkyl group, an aryl group, an alkylamino group, an alkyloxy group, an aryloxy group or an arylamino group, X
Is an oxygen atom or a sulfur atom, M is an n-valent metal atom,
n represents an integer.

In the general formula (I) or (II), R ₁ is preferably a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a monocyclic or condensed ring aryl having 6 to 10 carbon atoms. group, R ₂ is a linear or branched alkyl group having 4 to 20 carbon atoms, a substituted alkyl group (the substituent, an aryl group, a carboxyl group, a sulfo group, sulfoamino group,
There are aryloxy groups, alkyloxy groups, acylamino groups and the like. ), A cycloalkyl group having 5 to 9 carbon atoms, a monocyclic or condensed ring aryl group having 6 to 10 carbon atoms, a substituted aryl group (as a substituent, an alkyl group having 1 to 20 carbon atoms, a hydroxyl group, an aryl group, Carboxyl group, sulfo group,
There are sulfoamino groups, acylamino groups, and the like. ), An alkylamino group having 1 to 20 carbon atoms, a substituted alkylamino group (the substituent includes an aryl group, a carboxyl group, a sulfo group, a sulfoamino group, an acylamino group, etc.),
An alkyloxy group having 1 to 20 carbon atoms, a substituted alkyloxy group (as a substituent, an aryl group, a carboxyl group,
There are sulfo group, sulfoamino group, acylamino group and the like. ), An aryloxy group having 1 to 20 carbon atoms, a substituted aryloxy group (the substituent includes an alkyl group having 1 to 20 carbon atoms, a hydroxyl group, an aryl group, a carboxyl group, a sulfo group, a sulfoamino group, an acylamino group, etc. ), An arylamino group having 6 to 10 carbon atoms and a substituted arylamino group (the substituent includes an alkyl group having 1 to 20 carbon atoms, a hydroxyl group, a carboxyl group, a sulfo group, a sulfoamino group, an acylamino group, etc.). Is mentioned. Particularly preferably, R ₁ is a hydrogen atom, R ₂ is an alkyl group having 7 to 17 carbon atoms, an alkoxy-substituted alkyl group, an aryloxy-substituted alkyl group, an alkyloxy group having 7 to 17 carbon atoms, an aralkyloxy group, a carbon atom. They are an aryl group having 6 to 18 carbon atoms, an alkyl-substituted aryl group, and an alkylamino group having 12 to 18 carbon atoms.

Specific examples of the electron-accepting compound according to the present invention will be shown. (1) N-caproylanthranilic acid, (2)
N-pivaloylanthranilic acid, (3) N-capryloylanthranilic acid, (4) N- (2-ethylhexanoyl) anthranilic acid, (5) N-decanoylanthranilic acid, (6) N-lauroylanthranilic acid Acid, (7) N
-Myristoylanthranilic acid, (8) N-palmitoylanthranilic acid, (9) N-stearoylanthranilic acid, (10) N- (cyclohexylcarbonyl) anthranilic acid, (11) N- (p-toluenesulfonyl)
Anthranilic acid, (12) N- (isobutylsulfonyl) anthranilic acid, (13) N- (octylsulfonyl) anthranilic acid, (14) N- (2-ethylhexylsulfonyl) anthranilic acid, (15) N- (dodecylsulfonyl) Anthranilic acid, (16) N- (octadecylsulfonyl) anthranilic acid, (17) N- (dodecylbenzenesulfonyl) anthranilic acid, (18)
N- (dodecylsulfonyl) anthranilic acid, (19)
N- (mesitylenesulfonyl) anthranilic acid, (2
0) N- (2,4,6-triisopropylbenzenesulfonyl) anthranilic acid, (21) N- (octylcarbamoyl) anthranilic acid, (22) N- (2-ethylhexylcarbamoyl) anthranilic acid, (23) N-
(Cyclohexylcarbamoyl) anthranilic acid, (2
4) N- (dodecylcarbamoyl) anthranilic acid,
(25) N- (octadecylcarbamoyl) anthranilic acid, (26) N- (dodecylphenylcarbamoyl)
Anthranilic acid, (27) N- (cyclohexylthiocarbamoyl) anthranilic acid, (28) N- (octylthiocarbamoyl) anthranilic acid, (29) N- (2
-Ethylhexylthiocarbamoyl) anthranilic acid,
(30) N- (dodecylthiocarbamoyl) anthranilic acid,

(31) N- (octadecylthiocarbamoyl) anthranilic acid, (32) N- (hexadecylsulfonyl) anthranilic acid, (33) N-acetylanthranilic acid, (34) N-propionylanthranilic acid, (35) N- (n-butylcarbonyl) anthranilic acid, (36) N- (n-hexylcarbonyl) anthranilic acid, (37) N- (n-octylcarbonyl) anthranilic acid, (38) N-benzoylanthranilic acid, (39 ) N- (4-chlorobenzoyl) anthranilic acid, (40) N- (4-methoxybenzoyl) anthranilic acid, (41) N- (2-methoxybenzoyl) anthranilic acid, (42) N- (2-methylthiobenzoyl) ) Anthranilic acid, (43) N- (2-chlorobenzoyl) anthranilic acid (44) N- (phenoxyacetyl) anthranilic acid, (45) N- (4-methoxyphenoxyacetyl) anthranilic acid, (46) N- (phenylacetyl) anthranilic acid, (47) N- (phenoxycarbonyl) anthranilic acid , (48) N- (benzyloxycarbonyl) anthranilic acid, (49) N
-(2-phenoxypropionyl) anthranilic acid,
(50) N- (3-phenoxypropionyl) anthranilic acid, (51) N- (methoxyacetyl) anthranilic acid, (52) N- (methylsulfonyl) anthranilic acid, (53) N- (n-butylsulfonyl) anthranyl Acid, (54) N- (phenylsulfonyl) anthranilic acid, (55) N- (methoxycarbonyl) anthranilic acid, (56) N- (ethoxycarbonyl) anthranilic acid, (57) N- (n-butyloxycarbonyl) Anthranilic acid and the like can be mentioned.

On the other hand, the N-substituted anthranilic acid represented by the general formulas (I) and (II) of the present invention is converted into a polyvalent metal salt of its carboxyl group to obtain a remarkable color-developing ability which meets the object of the present invention. Indicates. In this case, the polyvalent metal is a typical element such as magnesium, calcium, aluminum or tin, or a transition element such as titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper or zinc. Particularly, as the polyvalent metal salt of N-substituted anthranilic acid represented by the general formula (I) or (II), a zinc salt or an aluminum salt is preferable. Among them, zinc salt has a high color developing ability. The N-substituted anthranilic acid derivatives represented by the general formulas (I) and (II) are oxides, hydroxides, carbonates and carboxylic acids of zinc, aluminum, titanium, silicon, boron, magnesium or calcium. When used in combination with one or more salts, the image storability is further improved. Among the metal compounds used in combination, zinc oxide, aluminum hydroxide, calcium carbonate,
Silicon dioxide and aluminum silicate are preferable, and zinc oxide is particularly preferable.

The dispersed particle size of the N-substituted anthranilic acid derivative or its metal salt according to the present invention after being atomized in a sand mill or the like is preferably 3 μm or less, preferably 2 μm or less in order to obtain color developing sensitivity. preferable.

Further, the N-substituted anthranilic acid derivative according to the present invention includes the well-known salicylic acid derivative, a metal salt of an aromatic carboxylic acid, a phenol derivative, a phenol resin, a novolac resin, a metal-treated novolac resin, a metal complex and an acid. An electron-accepting compound such as clay and bentonite may be used in combination. Examples of these are Japanese Patent Publication No. 40-9
309, JP-B-45-14039, JP-A-52-1.
40483, JP-A-48-51510, JP-A-57.
-210886, JP-A-58-87089, JP-A-59-112286, JP-A-60-176795, JP-A-61-95988 and the like.

To give an example of some of these, 4-tert-butylphenol, 4-phenylphenol, 2,
2'-dihydroxybiphenyl, 2,2-bis (4-
Hydroxyphenyl) propane (bisphenol A),
4,4'-sec-butylidene diphenol, 4,4 '
-Cyclohexylidene diphenol, bis (3-allyl-4-hydroxyphenyl) sulfone, 4-hydroxyphenyl-3 ', 4' dimethylphenyl sulfone, 4-
(4-isopropoxyphenylsulfonyl) phenol, 4,4′-dihydroxydiphenyl sulfide,
1,4-bis- (4'-hydroxycumyl) benzene,
1,3-bis- (4'-hydroxycumyl) benzene,
4,4'-thiobis (6-tert-butyl-3-methylphenol), 4,4'-dihydroxydiphenylsulfone, 4-hydroxybenzoic acid benzyl ester,
3,5-di-tert-butylsalicylic acid, 3-phenyl-5- (α, α-dimethylbenzyl) salicylic acid, 3
-Cumyl-5-t-octylsalicylic acid, 3,5-di-
t-butylsalicylic acid, 3-phenyl-5-t-octylsalicylic acid, 3-methyl-5-α-methylbenzylsalicylic acid, 3-methyl-5-cumylsalicylic acid, 3,5
-Di-t-octylsalicylic acid, 3,5-bis (α-methylbenzyl) salicylic acid, 3-cumyl-5-phenylsalicylic acid, 5-n-octadecylsalicylic acid, 4-pentadecylsalicylic acid, 3,5-bis (α , Α-Dimethylbenzyl) salicylic acid, 3,5-bis-t-octylsalicylic acid, 4-β-dodecyloxyethoxysalicylic acid, 4-methoxy-6-dodecyloxysalicylic acid, 4
There are -β-phenoxyethoxysalicylic acid, 4-β-p-ethylphenoxyethoxysalicylic acid, 4-β-p-methoxyphenoxyethoxysalicylic acid and the like, and metal salts thereof. The electron-accepting compound N- according to the present invention
The above electron-accepting compound is preferably mixed in a proportion of 10 to 100% by weight with respect to the substituted anthranilic acid derivative. Moreover, you may use together 2 or more types of said electron-accepting compounds.

The electron-accepting compound is preferably used in an amount of 50 to 800% by weight, more preferably 100 to 500% by weight of the electron-donating colorless dye.

Examples of the electron-donating colorless dye of the present invention include triphenylmethanephthalide compounds, fluorane compounds, phenothiazine compounds, indolylphthalide compounds, leucoauramine compounds, rhodaminelactam compounds, There are various compounds such as triphenylmethane compounds, triazene compounds, spiropyran compounds, and fluorene compounds. Specific examples of the phthalides include US Reissue Patent Specification No. 23,024, US Patent Specification Nos. 3,491,111, and 3,491,112,
No. 3,491,116 and No. 3,509,17
No. 4, specific examples of fluoranes are described in US Pat.
No. 24,107, No. 3,627,787, No. 3,
No. 641,011, No. 3,462,828, No. 3,681,390, No. 3,920,510, No. 3,959,571, specific examples of spiro dipyrans are US patent specifications. No. 3,971,808, pyridine and pyrazine compounds are described in US Pat.
No. 5,424, No. 3,853,869, No. 4,2
46,318, and specific examples of fluorene compounds are described in Japanese Patent Application No. 61-240989.

Of these, 2-arylamino-3-H, halogen- or alkyl-6-substituted aminofluorane, which develops black, are particularly effective. Specific examples include, for example, 2-anilino-3-methyl-6-diethylaminofluorane, 2-
Anilino-3-methyl-6-N-cyclohexyl-N-
Methylaminofluorane, 2-p-chloroanilino-3
-Methyl-6-dibutylaminofluorane, 2-anilino-3-chloro-6-diethylaminofluorane, 2-
Anilino-3-methyl-6-N-ethyl-N-isoamylaminofluorane, 2-anilino-3-methyl-6-
N-ethyl-N-dodecylaminofluorane, 2-o-
Chloroanilino-6-dibutylaminofluorane, 2-
Anilino-3-pentadecyl-6-diethylaminofluorane, 2-anilino-3-methyl-6-dibutylaminofluorane, 2-o-toluidino-3-methyl-6-
Diisopropylaminofluorane, 2-anilino-3-
Methyl-6-N-isobutyl-N-ethylaminofluorane, 2-anilino-3-methyl-6-N-ethyl-N
-Tetrahydrofurfurylaminofluorane, 2-anilino-3-chloro-6-N-ethyl-N-isoamylaminofluorane, 2-anilino-3-methyl-6-N-
Methyl-N-γ-ethoxypropylaminofluorane,
2-anilino-3-methyl-6-N-ethyl-N-γ-
Ethoxypropylaminofluorane, 2-anilino-3
-Methyl-6-N-ethyl-N-γ-propoxypropylaminofluorane, 2-anilino-3-methyl-6-
N-methyl-N-propylaminofluorane and the like can be mentioned.

A sensitizer may be added in addition to the electron-donating colorless dye and the electron-accepting compound. Examples of the sensitizer include JP-A-58-57989, JP-A-58-87094,
The compounds disclosed in JP-A-63-39375 and the like can be mentioned. Aromatic ethers (especially benzyl ethers, di (substituted phenoxy) alkanes, diphenyl ethers, particularly preferably 2-benzyloxynaphthalene, 1,2-di (3-methylphenoxy) ethane, 4-
Biphenyl-p-tolyl ether), aromatic ester (especially dibenzyl oxalate derivative, particularly preferably di (p-methylbenzyl oxalate)), biphenyl derivative (especially parabenzyl biphenyl, metaterphenyl) or fat The group amides, ureas or aromatic amides or ureas are representative. The sensitizer is preferably used in an amount of 50 to 800% by weight of the electron-donating colorless dye, more preferably 100 to 500% by weight. Two or more sensitizers may be used in combination. In particular, it is preferable to use an aliphatic amide and urea together with the aromatic compound. Examples of the aliphatic amide and urea include those represented by the general formula (I
Those listed as V) to (VI) are preferable.

[0019]

[Chemical 6]

[0020]

[Chemical 7]

[0021]

[Chemical 8]

In the above formula, R ₈ is an alkyl group having 12 to 24 carbon atoms or an alkenyl group having 12 to 24 carbon atoms,
R ₉ represents a hydrogen atom, an alkyl group having 1 to 24 carbon atoms or a methylol group, and R ₁₀ represents an alkylene group having 1 to 8 carbon atoms.

Specific examples thereof include stearic acid amide, palmitic acid amide, oleic acid amide, stearyl urea and palmityl urea. Further, N-substituted amide compounds such as methylol stearic acid amide and ethylenebisstearic acid amide are also included. The addition amount of these amide compounds or urea compounds to the aromatic compound is preferably 1 to 100% by weight. More preferably 2-5
It is 0% by weight.

Next, a method for producing a typical thermosensitive coloring layer of the present invention will be described. Electron-donating colorless dye, electron-accepting compound,
The sensitizer is dispersed with a water-soluble polymer aqueous solution such as polyvinyl alcohol to a particle size of several microns or less using a ball mill, a sand mill or the like. The sensitizer is an electron-donating colorless dye,
In addition to either or both of the electron-accepting compounds, they may be dispersed simultaneously, or in some cases, a eutectic with an electron-donating colorless dye or an electron-accepting compound may be prepared and dispersed. These dispersions are mixed after dispersion, and if necessary, pigments, surfactants, binders, metal soaps, waxes,
Antioxidant, ultraviolet absorber, etc. are added to make a heat-sensitive coating liquid. The heat-sensitive coating liquid obtained is a high-quality paper, a high-quality paper having an undercoat layer,
After being applied and dried on synthetic paper, plastic film, etc.,
The calendering process imparts smoothness to the target thermal recording material. At this time, it is particularly preferable in terms of dot reproducibility to use a support having a smoothness defined by JIS-8119 of 500 seconds or more, particularly 800 seconds or more. In order to obtain a support having a smoothness of 500 seconds or more, (1) a highly smooth one such as synthetic paper or a plastic film is used, and (2) an undercoat layer containing a pigment as a main component is provided on the support. (3) means for increasing the smoothness of the support by using a super calender or the like.

As the binder used in the present invention,
A compound that is soluble in 5% by weight or more in water at 25 ° C. is preferable. Specifically, polyvinyl alcohol (including modified polyvinyl alcohol such as carboxy-modified, acetoacetyl-modified, itaconic acid-modified, maleic acid-modified, and silica-modified) , Methyl cellulose, carboxymethyl cellulose, starches (including modified starch), gelatin, gum arabic, casein, styrene-maleic anhydride copolymer hydrolyzate, polyacrylamide, saponified vinyl acetate-polyacrylic acid copolymer, etc. Can be given. These binders are used not only for dispersion but also for the purpose of improving the coating strength.
A latex binder of a synthetic polymer such as a butadiene copolymer, a vinyl acetate copolymer, an acrylonitrile / butadiene copolymer, a methyl acrylate / butadiene copolymer, or polyvinylidene chloride can be used together. Further, if necessary, a crosslinking agent for a suitable binder may be added depending on the kind of the binder.

Examples of pigments used in the present invention include calcium carbonate, barium sulfate, lithopone, wax, kaolin, silica and amorphous silica. As the metal soap, higher fatty acid metal salt is used, zinc stearate,
Calcium stearate, aluminum stearate, etc. are used. Further, a surfactant, an antistatic agent, an ultraviolet absorber, an antifoaming agent, a conductive agent, a fluorescent dye, a coloring dye, etc. may be added if necessary. The applied heat-sensitive recording material is dried and subjected to treatment with a calendar or the like before use. Further, a protective layer may be provided on the thermosensitive coloring layer, if necessary. Any known protective layer can be used as the protective layer for the heat-sensitive recording material.
Further, if necessary, a back coat layer may be provided on the surface of the support of the thermosensitive recording material opposite to the thermosensitive coloring layer. As the back coat layer, any one known as a back coat layer of a thermal recording material can be used.
Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the examples.

[0027]

【Example】

(Example-1) 2-anilino-3-methyl-6-dibutylaminofluorane as an electron-donating colorless dye, zinc N-benzoylanthranilate as an electron-accepting compound, and di (p-oxalate) as a sensitizer. 20 g of each of methylbenzyl) ester and 100 g of a 5% aqueous solution of polyvinyl alcohol (Kuraray PVA-105) were dispersed in a ball mill for a whole day and night so that the average particle diameter was 1.5 μm or less to obtain respective dispersions. Further, 80 g of calcium carbonate was dispersed with 160 g of a 0.5% sodium hexametaphosphate solution by a homogenizer to obtain a pigment dispersion liquid. 5 g of each of the dispersions prepared as described above was used as an electron-donating colorless dye dispersion, 5 g of electron-accepting compound dispersion, 10 g of oxalic acid di (p-methylbenzyl) ester dispersion, and 5 g of calcium carbonate dispersion. Then, 3 g of a 21% zinc stearate emulsion was added to obtain a heat-sensitive coating liquid. This thermosensitive color-developing layer coating solution was applied to a high-quality paper having a basis weight of 50 g / m ² using a wire bar so that the dry weight of the coating layer was 5 g / m ² , and dried at 50 ° C. for 1 minute to prepare a thermosensitive recording paper Got

Example 2 The procedure of Example 1 was repeated except that zinc N- (phenylacetyl) anthranilate was used instead of zinc N-benzoylanthranilate to prepare a heat-sensitive coating solution. A thermal recording paper was obtained by the same method.

(Example-3) In the preparation of Example-1, except that zinc N-benzoylanthranilate was used instead of zinc N- (benzyloxycarbonyl) anthranilate to prepare a heat-sensitive coating liquid. A heat-sensitive recording paper was obtained by the same method.

Example-4 A heat-sensitive coating solution was prepared by using zinc N- (2-phenoxypropionyl) anthranilate instead of using zinc N-benzoylanthranilate in the preparation of Example-1. A thermal recording paper was obtained by the same method except for the above.

(Example-5) In the preparation of Example-1, a heat-sensitive coating liquid was prepared by using zinc N- (phenoxyacetyl) anthranilate instead of zinc N-benzoylanthranilate. A thermal recording paper was obtained by the same method.

(Example-6) The procedure of Example-1 was repeated except that N- (phenoxyacetyl) anthranilic acid was used instead of zinc N-benzoylanthranilate to prepare a heat-sensitive coating solution. A heat sensitive recording paper was obtained by the method described in 1.

Example 7 N- (phenoxyacetyl) anthranilic acid was used in place of zinc N-benzoylanthranilate in the preparation of Example-1, and 80 g of zinc oxide was added to sodium hexametaphosphate. A thermosensitive recording paper was obtained by the same method except that 160 g of a 0.5% solution and 1 g of a dispersion liquid dispersed by a homogenizer were added to prepare a thermosensitive coating liquid.

(Example-8) The procedure of Example-1 was repeated except that 2-benzyloxynaphthalene was used in place of the oxalic acid di (p-methylbenzyl) ester to prepare the heat-sensitive coating solution. A thermal recording paper was obtained by the same method.

Example 9 Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. A heat-sensitive recording paper was obtained by the same method except that a heat-sensitive coating liquid was prepared by using 2-benzyloxynaphthalene instead of using it.

Example 10 Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. A heat-sensitive recording paper was obtained by the same method except that a heat-sensitive coating liquid was prepared by using parabenzyl biphenyl instead of using it.

Example 11 Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. A thermosensitive recording paper was obtained by the same method except that a thermosensitive coating liquid was prepared using metaterphenyl instead of using it.

(Example-12) Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. A heat-sensitive recording paper was obtained by the same method except that a heat-sensitive coating liquid was prepared by using 4-biphenyl-p-tolyl ether instead of using it.

(Example-13) Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. A thermosensitive recording paper was obtained by the same method except that a thermosensitive coating liquid was prepared by using 1,2-di (3-methylphenoxy) ethane instead of using it.

Example 14 In the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate was used in place of zinc N-benzoylanthranilate, and a 21% stearic acid amide dispersion ( A thermosensitive recording paper was obtained by the same method except that 2 g of Chukyo Yushi Co., Ltd. Himicron G270 was added to prepare a thermosensitive coating liquid.

(Example-15) Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate and oxalic acid di (p-methylbenzyl) ester were used. Instead of using 2-benzyloxynaphthalene, 2 g of 22% methylol stearoamide dispersion (Hydrin D-130 manufactured by Chukyo Yushi Co., Ltd.) was further added to prepare a heat-sensitive coating solution, which was the same as the above. Thermal recording paper was obtained by the method.

Example 16 Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate was replaced with 2-anilino-3-methyl-6-dibutyl. A heat-sensitive recording paper was obtained by the same method except that a heat-sensitive coating solution was prepared by using 2-anilino-3-methyl-6-N-ethyl-N-isoamylaminofluorane instead of using aminofluorane. It was

Example 17 Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate was replaced with 2-anilino-3-methyl-6-dibutyl. Thermal recording paper by the same method except that a thermosensitive coating liquid was prepared using 2-anilino-3-methyl-6-N-ethyl-N-tetrahydrofurfurylaminofluorane instead of using aminofluorane. Got

(Example-18) Instead of using zinc N-benzoylanthranilate in the preparation of Example-1, zinc N- (phenoxyacetyl) anthranilate was replaced with 2-anilino-3-methyl-6-dibutyl. A heat-sensitive recording paper was obtained by the same method except that the heat-sensitive coating solution was prepared by using 2-o-chloroanilino-6-dibutylaminofluorane instead of using aminofluorane.

Comparative Example-1 A thermal recording paper was obtained in the same manner as in Example 1, except that bisphenol A was used instead of the zinc N-benzoylanthranilate to prepare a thermal coating solution. .

(Comparative Example 2) A heat-sensitive coating solution was prepared in the same manner as in Example 1, except that 4-hydroxybenzoic acid benzyl ester was used instead of the zinc N-benzoylanthranilic acid of Example 1 to prepare a heat-sensitive coating solution. I got the recording paper.

Comparative Example-3 Instead of using the zinc N-benzoylanthranilate of Example-1, 4- (4-
A heat-sensitive recording paper was obtained by the same method except that a heat-sensitive coating solution was prepared using isopropoxyphenylsulfonyl) phenol.

The heat-sensitive recording paper obtained as described above is
Surface treatment was performed with a calender, and the smoothness was adjusted to be Beck's smoothness of 300 ± 50 seconds to obtain a heat-sensitive recording material. The thermal recording paper was evaluated as follows. (1) Color density is 30 mJ / printing energy with a Kyocera printing tester
The image was printed at mm ² and the color density was measured with a Macbeth densitometer.
The higher this value, the higher the sensitivity of the thermal recording paper. (2)
The chemical resistance test was conducted by impregnating filter paper with ethanol and a plasticizer (dioctyl phthalate) and overlaying it on the color-developing surface of the recording paper obtained by the above method, and then the fog on the white background and the discoloration of the color-developed part (discoloration) Was evaluated. The above results are shown in Tables 1 and 2.

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

As can be seen from the results of Tables 1 and 2, the recording material of the present invention has a high sensitivity and does not cause fog color development or decolorization of the color development portion due to chemicals, and has extremely excellent performance. You can see that

Claims (6)

[Claims] 1. A thermosensitive recording material comprising a support and a thermosensitive coloring layer containing an electron-donating colorless dye and an electron-accepting compound, which is represented by the following general formula (I) or (II) in the thermosensitive coloring layer. A heat-sensitive recording material containing an N-substituted anthranilic acid derivative or a metal salt thereof. [Chemical 1] [Chemical 2] In the above formula, R ₁ is a hydrogen atom, an alkyl group or an aryl group, R ₂ is an alkyl group, a cycloalkyl group, an aryl group, an alkylamino group, an alkyloxy group, an aryloxy group or an arylamino group, and X is oxygen. Atom or sulfur atom, M represents an n-valent metal atom, and n represents an integer. 2. The heat-sensitive recording material according to claim 1, wherein the heat-sensitive color forming layer further contains a metal compound. 3. The heat-sensitive recording material according to claim 2, wherein the metal compound is zinc oxide. 4. An electron-donating colorless dye is represented by the following general formula (II
The heat-sensitive recording material according to claim 1, which is a fluoran compound represented by I). [Chemical 3] In the above formula, R ₃ and R ₄ represent an alkyl group or an aryl group, and R ₅ , R ₆ and R ₇ represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group. 5. Di (p-methylbenzyl) oxalate, 2-benzyloxynaphthalene, parabenzyl biphenyl, metaterphenyl, 4-biphenyl-in the thermosensitive coloring layer.
The heat-sensitive recording material according to claim 1, further comprising a sensitizer selected from the group consisting of p-tolyl ether and 1,2-di (3-methylphenoxy) ethane. 6. A thermosensitive coloring layer containing di (p-methylbenzyl) oxalate, 2-benzyloxynaphthalene, parabenzyl biphenyl, metaterphenyl, 4-biphenyl-.
A sensitizer selected from the group consisting of p-tolyl ether and 1,2-di (3-methylphenoxy) ethane is contained, and an aliphatic amide compound or an aliphatic urea compound is further used in combination. The heat-sensitive recording material as described in 5 above.