JPH03231893A - Thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a thermal recording material by providing a thermal recording layer compounded with a specific basic dye and a salicylic acid derivative containing an aryloxyalkyloxy group as a substituent on a support. CONSTITUTION:3-(N-ethyl-N-tetrahydrofurylamino)-6-methyl-7- phenylaminofluroane being a basic dye and a salicylic acid derivative having an aryloxyalkyloxy group as a substituent or a polyvalent metal salt thereof being a coupler are dispersed in a medium having a binder dissolved or dispersed therein to prepare a coating solution. This coating solution is applied to a support such as paper or a plastic film and dried to form a thermal recording layer to prepare a thermal recording material. In order to improve color forming capacity, it is pref. to together use inorg. pigment in an amount of about 0.5-3 pts.wt. per one pts. wt. of the coupler.

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a heat-sensitive recording medium, and particularly to a heat-sensitive recording medium that has excellent color development and storage stability of recorded images, and has extremely high whiteness in blank areas. It is.

``Prior art'' A thermosensitive recording material that utilizes a color reaction between a colorless or light-colored basic dye and an organic or inorganic coloring agent to obtain a recorded image by bringing the two light-colored substances into contact with each other using heat is well known. (Are known.

Recently, with the remarkable progress of thermal recording methods, the fields and forms of their use are diversifying, and they are used not only as recording media for thermal facsimiles and thermal printers, but also as recording media for POS (PoiS).
Its use in new applications such as labels (NT of 5ales) is also rapidly increasing.

``Problem to be solved by the invention'' However, conventional heat-sensitive recording materials using phenolic compounds as coloring agents have the drawback that white paper areas develop color or colored areas change color or fade depending on the environmental conditions during storage or use. There is.

Therefore, it has recently been proposed to use salicylic acid derivatives as coloring agents for thermosensitive recording materials, and a number of salicylic acid derivatives have been proposed. In general, heat-sensitive recording materials that use salicylic acid derivatives or their polyvalent metal salts as coloring agents have high color density and whiteness in blank areas, and are also relatively stable in colored images, and are exposed to sunlight for long periods of time. This is advantageous in terms of long-term storage of records, since the recorded images will hardly change color or fade even if stored under high temperature or high humidity environments. Further, by using a salicylic acid derivative as a coloring agent, it is possible to obtain a certain improvement effect on discoloration and fading of the colored portion due to contact with the vinyl chloride film. however,
A sufficient improvement effect has not yet been obtained regarding the defect that the blank portion develops color when the blank portion is placed in contact with a vinyl chloride film, and there is a strong demand for improvement.

In view of the current situation, the present inventors have conducted extensive studies with the aim of improving the above-mentioned defects observed in thermosensitive recording materials that utilize a color reaction between a basic dye and a coloring agent.

As a result, 3-(N-ethyl-N-
Tetrahydrofurfurylamino)-6-methyl-7-phenylaminofluorane is used in combination with at least one salicylic acid derivative or a polyvalent metal salt thereof having an aryloxyalkyloxy group as a substituent as a coloring agent. It has been discovered that a heat-sensitive recording medium with excellent color development and high whiteness in the blank area (particularly in the storage stability of the blank area and recorded image when in contact with vinyl chloride film) can be obtained, and the present invention I was able to complete it.

"Means for Solving the Problems" The present invention provides a thermosensitive recording layer provided on a support with a thermosensitive recording layer containing a colorless or light-colored basic dye and a coloring agent capable of coloring when in contact with the dye. In the heat-sensitive recording layer, 3-(N-ethyl-N-tetrahydrofurfurylamino)-6methyl-7-phenylaminofluorane was placed as a basic dye and an aryloxyalkyloxy group was placed as a coloring agent. This heat-sensitive recording material is characterized in that it contains at least one salicylic acid derivative or a polyvalent metal salt thereof as JAM.

"Function" The present invention provides 3-(N-ethyl-N-
Selectively using tetrahydrofurfurylamino)-6-methyl-7-phenylaminofluorane and a salicylic acid derivative and/or its polyvalent metal salt having an aryloxyalkyloxy group as a substituent as a coloring agent. Not only is the color development density sufficient and the whiteness of the blank area is high, and the colored image is extremely stable, but also the storage stability of the blank area, especially when in contact with vinyl chloride film, is extremely long. This provides an excellent thermosensitive recording medium.

Among the salicylic acid derivatives having an aryloxyalkyloxy group as a substituent used in the present invention, a salicylic acid derivative represented by the following general formula (1) is preferable.

[Wherein, group, alkylcarbonyloxy group, nitro group, hydroxyl group, or halogen atom, m represents an integer of 1 to G, and n represents an integer of 1 to 5. ] Among the salicylic acid derivatives represented by the above general formula CL), derivatives in which X is a hydrogen atom, an alkyl group of 01 to 3, an alkoxyl group of 01 to 2, a halogen H atom, and m is 2 are especially suitable for the white part. This method is more preferable because a heat-sensitive recording material with excellent storage stability can be obtained.

As the polyvalent metal that forms a salt with the salicylic acid derivative represented by the general formula (1), divalent, trivalent or tetravalent metals are preferred, and zinc, calcium, aluminum, magnesium and tin are particularly preferred.

Specific examples of the salicylic acid derivative represented by the general formula (1) include the following compounds.

4-(2-phenoxyethoxy)salicylic acid, 4-(3
-phenoxypropoxy)salicylic acid, 4-(4-phenoxybutoxy)salicylic acid, 4(2-p-methylphenoxyethoxy)salicylic acid, 4-(2-p-methoxyphenoxyethoxy)salicylic acid, 4-(2-p-
Ethoxyphenoxyethoxy) salicylic acid, 4-(2-
p-chlorophenoxyethoxy) salicylic acid, 4-(2
0-chlorophenoxyethoxy) salicylic acid, 4(2-
o, p-dimethylphenoxyethoxy) salicylic acid, 4
(2-m-methylphenoxyethoxy) salicylic acid, 4-(2-p-benzyloxyphenoxyethoxy) salicylic acid, 4-(2-o-methoxyphenoxyethoxy) salicylic acid, 4 (2-m-methoxyphenoxyethoxy) salicylic acid, 4-(2-p-phenylphenoxyethoxy)salicylic acid and the like. Of course, it is not limited to these salicylic acid derivatives.

In addition, two or more kinds of these salicylic acid derivatives and/or their polyvalent metal salts can be used in combination, if necessary.

In the present invention, there are no particular limitations on the ratio of the combination of 3-(N-ethyl-N-tetrahydrofurfurylamino)-6-methyl-7phenylaminofluorane and the salicylic acid derivative and/or its polyvalent metal salt. but generally 3-(N-ethyl-N-tetrahydrofurfurylamino)-6methyl-7-phenylaminofluorane 10
50 to 700 parts by weight, preferably 100 to 50 parts by weight of the salicylic acid derivative and/or its polyvalent metal salt based on 0 parts by weight.
It is desirable to adjust the amount within a range of 0 parts by weight.

The present invention provides a heat-sensitive recording medium that uses a specific salicylic acid derivative and/or its polyvalent metal salt as described above, and has excellent storage stability of blank areas, especially when in contact with a vinyl chloride film. However, this property can be further improved by using other metal compounds in combination.

Such metal compounds include divalent, trivalent, or tetravalent metals such as zinc, magnesium, barium, calcium, aluminum, tin, titanium, nickel, cobalt,
Metal oxides and hydroxides selected from manganese, iron, etc.
Examples include sulfides, halides, carbonates, phosphates, silicates, sulfates, nitrates, and halogen complex salts,
Among these, zinc compounds are particularly preferred.

Specific examples of metal compounds include zinc oxide, zinc hydroxide, zinc aluminate, zinc sulfide, zinc carbonate, zinc phosphate, zinc silicate, aluminum oxide, magnesium oxide,
titanium oxide, aluminum hydroxide, aluminum silicate,
Examples include aluminum phosphate, magnesium aluminate, magnesium hydroxide, magnesium carbonate, and magnesium phosphate. Of course, two or more of these metal compounds can also be used in combination.

The amount of the metal compound used is not necessarily limited, but is usually in the range of 1 to 500 parts by weight, preferably 5 to 300 parts by weight per 100 parts by weight of the salicylic acid derivative and/or its polyvalent metal salt. It is preferable to adjust with

In the heat-sensitive recording material of the present invention, various known coloring agents such as salicylic acid derivatives, phenol derivatives, and acid clay can be used in combination within the range that does not impede the desired effect. Specific examples of such known coloring agents include the following.

Benzoic acid, 4-tert-butylbenzoic acid, 4-chlorobenzoic acid, 4-nitrobenzoic acid, phthalic acid, gallic acid,
Salicylic acid, 3-isopropylsalicylic acid, 3-phenylsalicylic acid, 3-cyclohexylsalicylic acid, 3,5
-diter t-butylsalicylic acid, 3-methyl-5
-Benzylsalicylic acid, 3-(α-methylbenzyl)salicylic acid, 3-chloro-5-(α-methylbenzyl)salicylic acid, 3-phenyl-5-(α,α-dimethylbenzyl)salicylic acid, 3,5-di- Aromatic pressure carboxylic acids such as α-methylbenzylsalicylic acid, 2-hydroxy-1-benzyl-3-naphthoic acid, 4.4'-isopropylidene diphenol (bisphenol A), 4.4'-isopropylidene bis(2-chloro phenol), 4.4'
-isopropylidene bis(2,6-dichlorophenol), 4,4'-isopropylidene bis(2,6-dibromophenol), 4,4'-isopropylidene bis(2-methylphenol), 4,4'-isopropylidene Screw(
2,6-dimethylphenol), 4゜4'-isopropylidene bis(2-'tert-butylphenol),
4. 4'-5ec-butylidene diphenol, 2,
2'-bis(4-hydroxyphenyl)-4-methylpentane, 4,4'-cyclohexylidenebisphenol, 4,4'-cyclohexylidenebis(2-methylphenol), 4ter t-butylphenol, 4-phenyl Phenol, 4-hydroxydiphenoxide, α-
Naphthol, β-naphthol, methyl-4-hydroxyhenzoate, benzyl-4-hydroxyhensoate, 2.2゛-thiobis(4,6-dichlorophenol)
, 4-tert-octylcatechol, 2,2'-methylenebis(4-methyl-6tert-butylphenol), 2,2'-dihy-l'roquinbiphenyl, methyl-
Bis(4-hydroxyphenyl)acetate, methyl-
Bis(4-hydroxyphenyl)acetate, ethyl-
Bis(4-hydroxyphenyl)acetate, benzyl-bis(4-hydroxyphenyl)acetate, 4.4
'(p-phenylene diisopropylidene) diphenol, 4.4'-(m-phenylene diisopropylidene) diphenol, 4-hydroxydiphenylsulfone, 4.
4'-dihydroxydiphenylsulfone, 4-hydroxy-4'-methyl-diphenylsulfone, 4-hydroxy-4'-isopropoxy-diphenylsulfone, 4-
Phenolic compounds such as hydroxy-3',4'-tetramethylenediphenylsulfone, 3,3'-diallyl-4,4'-dihydroxydiphenylsulfone; Phenols such as p-phenylphenol-formalin resin, p-butylphenol-acetylene resin Organic coloring agents such as resins; and salts of these organic coloring agents with polyvalent metals such as zinc, magnesium, aluminum, calcium, titanium, manganese, tin, nickel, etc.; such as antipyrine complexes of zinc thiocyanate. Metal complex compounds, etc.

Further, in the heat-sensitive recording material of the present invention, various known colorless or light-colored basic dyes can be used in combination within a range that does not impede the desired effect. Specific examples of such basic dyes include the following.

3.3-bis(p-dimethylaminophenyl)6-dimethylaminophthalide, 3.3-bis(p-dimethylaminophenyl)phthalide, 3-(4-dimethylaminophenyl)-3-(4-diethylamino- 2-Methylphenyl)-6-(dimethylamino)phthalide, 3-(p-dimethylaminophenyl)-3-(1,2-dimethylindol-3-yl)phthalide, 3-(p-dimethylaminophenyl)- 3-(2-methylindol-3-yl)
Phthalide, 3,3-bis(1,2-dimethylindol-3-yl)-5-dimethylaminophthalide, 3,3-
Bis(1,2-dimethylindol-3-yl)-6-
Dimethylaminophthalide, 3,3-bis(9-ethylcarbazol-3-yl)-6-dimethylaminophthalide,
3゜3-bis(2-phenylindol-3-yl)-
6-dimethylaminophthalide, 3-p-dimethylaminophenyl-3-(1-methylpyrrol-3-yl)-6-
Triallylmethane dyes such as dimethylaminophthalide;
4.4'-bis-dimethylaminobenzhydrylbenzyl ether, N-halophenyl-leucoolamine, N-
2,4゜Diphenylmethane dye R such as 5-trichlorophenylleucoauramine; 3,3-bis(1,1-bis(4-viropidinophenyl)ethylene-2yl)-4,
5,6,7-tetrabromophthalide, 3,3-bis(1
-(4-methoxyphenyl)1-(4-dimethylaminophenyl)ethylene 2-yl) -4,5,6,7-tetrachlorophthalide, 3.3-bis(1-(4-methoxyphenyl)- Divinylphthalide dyes such as 1-(4-pyrrolidinophenyl)ethylene 2-yl)-4,5,6,7-tetrachlorophthalide; Thiazine dyes such as benzoylleucomethylene blue and p-nitrobenzoylleucomethylene blue ; 3-methyl-spiro-dinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3-phenyl-spirodinaphthopyran, 3-henzylo-spirodinaphthobilane, 3-methylamino I-(6'-methoxyhenzo)spiropyran, Spiro dyes such as 3-propyl-spirodihenzopyran - rhodamine B-anilinolactam, rhodamine (p-nitroanilino)lactam,
Lactam dyes such as rhodamine (0-chloroanilino)lactam; 3-dimethylamino-7-methoxyfluoran, 3-diethylamino-6-methoxyfluoran, 3
-diethylamine-7-methyl-7-chlorofluorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-6,7-dimethylfluorane, 3-(N-
Ethyl-p-toluidino)-7methylfluorane, 3-
Diethylamino-7-(N-acetyl-N-methylamino)fluorane, 3-diethylamino-'1-N-methylaminofluorane, 3-diethylamino-7-dihendylaminofluorane, 3-diethylamino-7-N Methyl-N-benzylaminofluorane, 3-diethylamine-7-(N-chloroethyl-N-methylamino)fluorane, 3-diethylamino 7-N-diethylaminofluorane, 4-benzylamino-8-diethylamino-benzo(a ) Fluorane, 3-(4-(4-dimethylaminoanilino)anilino)-7-chloro-6-methylfluoran, 8-(4-(4-cinethylaminoanilino)anilino)-henzo(a) Fluorane, 3(N-
Ethylnyl-4luidino)-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-p-toluidino)-6-methyl-7-(p-toluidino)fluorane, 3
-diethylamino 6-medy-7-phenylaminofluorane, 3-diethylamino-7-(2-carbomethoxyphenylamino)fluoran, 3-(N-ethyl N-isoamylamino)-6-methyl-7-phenylaminofluorane, 3-(N-cyclohexyl-N-methylamino)-6-methyl-7-phenylaminofluorane, 3
-pyrrolidino-6-methyl-7-phenylaminofluorane, 3-piperidino-6-methyl-7-phenylaminofluorane, 3-diethylamino-6-methyl-7xylidinofluorane, 3-diethylamino-7(0- chlorophenylamino) fluorane, 3-dibdelamino-7
-(0-chlorophenylamino)fluorane, 3-(N
-Methyl-Nnpropylamine)-6-methyl-7-
Phenylaminofluorane, 3-(N-ethyl-N-isophthylamino)-6-methyl-7-phenylaminofluorane, 3-(N-methyl-N-n-hexylamino)-6-methyl-7-phenyl Aminofluorane, 3
-dibentylamino-6-methyl 7-phenylaminofluorane, 3-(!l-(3ethoxypropyl)-N
-Methylamine]-6methyl-7-phenylaminofluorane, 3[N-edy-N-(3-ethoxypropyl)amine]-6-methyl-7-phenylaminofluorane, 3-diethylamine-7-[m -(trifluoromethyl)phenylaminocofluorane, 3diethylamino-7-(0-fluorophenylamino)fluorane, 3
-dibutylamino-7(0-fluorophenylamino)
Fluoran, 3-diethylamine-6-chloro-7-phenylaminofluorane, 3-(N-ethyl-N-n-hexylamino)-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-N -cyclopentylamino)-6-methyl-7-phenylaminofluorane; 3,6-t7s(dimethylamino)fluorene-9-spiro-3'-6'dimethylamino)phthalide, 3-diethylamino -6-(N-allyl-N-
methylamino)fluorene-9-spiro-3'-(6'
-dimethylamino)phthalide, 3,6-bis(dimethylamino)-spiro[fluorene-9,6'-6'11-
Chromeno (43-b) indole], 3゜6-bis (
dimethylamino)-3'-methyl-spiro[fluorene-9,6''6'H-chromeno(4,3-b)indole), 3,6-bis(diethylamino)-3'-methyl-spiro[fluorene-96 '-6'H-chromeno (4,
3-b) Indole] and other fluorene dyes. Of course, it is not limited to these dyes,
Two or more types of dyes can also be used together.

Furthermore, in the heat-sensitive recording medium of the present invention, various thermofusible substances can be used as a recording sensitivity improver in order to obtain high-speed recording performance. As a thermofusible substance that can cause
For example, caproic acid amide, capric acid amide, palmitic acid amide, stearic acid amide, oleic acid amide,
Erucic acid amide, linoleic acid amide, linoleic acid amide, N-methyl stearic acid amide, stearic acid anilide, N-methyl oleic acid amide, henzanilide, linoleic acid anilide, N-ethyl capric acid amide, N-
Butyl lauric acid amide, N-octadecyl acetamide, N-oleic acetamide, N-oleyl henzamide, N-stearylcyclohexylamide, polyethylene glycol, ■-hensyloxynaphthalene, 2-
Hensyloxynaphthalene, 1-hydroxynaphthoic acid phenyl ester, 1,2-diphenoxyethane, 1.
4-diphenoxybutane, 1,2-bis(3methylphenoxy)ethane, 12-bis(4methoxyphenoxy)
Ethane, 1-phenoxy 2-(4-chlorophenoxy)
Ethane, 1-phenoxy-2-(4-methoxyphenoxy)ethane, 1-(2-methylphenoxy)-2-(
4-methoxyphenoxy)ethane, dihensyl terephthalate, dihenzyl oxalate, di(4-methoxyphenoxy) oxalate
methylhensyl), p-hensyloxybenzoic acid hensyl ester, p-hensylbiphenyl 1,5-bis(p
-methoxyphenoxy)3-oxa-bencune, 1.4
Examples include compounds such as ~bis(2-vinyloxyethoxy)henzene, p-biphenyl-pt-lyl ether, and henzyl-p-methylthiophenyl ether.

The heat-sensitive recording material of the present invention is produced by dispersing a specific basic dye of the present invention and a salicylic acid derivative or a polyvalent metal salt thereof in a medium in which a binder is dissolved or dispersed.
It is produced by coating on a suitable support such as a plastic film, synthetic paper, woven fabric sheet, or molded product.

Examples of binders include starches, cellulose, protein fiff, gum arabic, polyvinyl alcohol, styrene/maleic anhydride copolymer salt, styrene/butadiene copolymer emulsion, vinyl acetate/maleic anhydride copolymer salt, A polyacrylate or the like is appropriately selected, and the total solid content in the coating liquid is 10 to 40% by weight, preferably 1.
It is blended in an amount varying from 5 to 30% by weight.

In addition, for the purpose of improving coloring ability, matting the surface of the recording layer, improving writing properties, etc., an inorganic RN additive is generally added in an amount of 0.1 to 10 parts by weight, preferably 0.5 parts by weight, per 1 part by weight of the coloring agent. ~3
They can be used together in parts by weight, and further auxiliary agents such as dispersants, ultraviolet absorbers, thermofusible substances, antifoaming agents, fluorescent dyes, and coloring dyes can be used in combination as necessary. .

There are no particular restrictions on the preparation method or application method of the coating liquid, and the amount applied is generally 2 to 12% by dry weight.
Approximately g/g is applied.

On the recording layer formed as described above, a water-soluble polymer or a water-dispersible polymer of 0.2 to 10 g/n (preferably 0.5 to 3 g/rd) is added for the purpose of protecting the recording layer. It is of course possible to provide an overcoat layer mainly composed of a polymer emulsion or to provide an undercoat layer on the support, and various known techniques f#j in the field of heat-sensitive recording material manufacturing can be added as appropriate. It is.

"Example J" The present invention will be explained in more detail with reference to Examples, but of course the present invention is not limited thereto.In addition, unless otherwise specified, parts and percentages in the examples are parts by weight and parts by weight, respectively. Indicates weight %.

Example 1 ■ Preparation of liquid A 3-(N-ethyl-N-tetrahydrofurfurylamino)-6-methyl-7-phenylaminofluorane 10 parts 1.2-bis(3-methylphenoxy)ethane 20 parts Methyl cellulose 5 % aqueous solution 20 parts water 1
10 parts of this composition was ground in a sand mill until the average particle size was 2 μm.

■ Preparation of B solution 4-30 parts of zinc salt of (2-p-methoxyphenoxyethoxy) salicylic acid 5% methylcellulose dissolved in water 60 parts water
110
This composition was ground in a sand mill until the average particle size was 3 μm.

■ Formation of recording body 160 parts of liquid A, 200 parts of liquid B, silicon oxide pigment (oil absorption rate:
180/100g), 150 parts of a 20% oxidized starch aqueous solution, and 210 parts of water were combined and stirred to obtain a coating liquid. The resulting coating liquid was coated on a 50 g/m double-sided paper to give a dry weight of 6.0 g/m and dried to obtain a thermal record I.6.

Examples 2-3 In the preparation of Example 10B solution, instead of the zinc salt of 4-(2-p methoxyphenoxyethoxy) salicylic acid,
A thermosensitive recording material was obtained in the same manner as in Example 1 except that the following compounds were used.

Example 2: Zinc salt of 4-(2-p-methylphenoxyethoxy)salicylic acid Example 3: Zinc salt of 4-(2-phenoxyethoxy)salicylic acid Example 4 In the preparation of Solution B of Example 1, 4-( 30 parts of zinc salt of 2-p methoxyphenoxyethoxy) salicylic acid, 1 part of water
A thermosensitive recording material was obtained in the same manner as in Example 1, except that 30 parts of 4-(2-pmethoxyphenoxyethoxy)salicylic acid, 30 parts of zinc oxide, and 80 parts of water were used instead of 10 parts.

Comparative Example 1 In the preparation of Solution B of Example 1, instead of the zinc salt of 4-(2-p methoxyphenoxyethoxy) salicylic acid, 3
A thermosensitive recording material was obtained in the same manner as in Example 1 except that , 5-bis(α-methylhensyl)salicylic acid was used.

Comparative Examples 2-3 A of Example 1? fj, in the preparation of 3-(N-ethyl-N-tetrahydrofurfurylamine)-6methyl-7
A thermosensitive recording material was obtained in the same manner as in Example 1 except that the following compound was used instead of -phenylaminofluorane.

Comparative example 2: 3-(N-cyclohexyl-N-methylamine)-6-methyl-7-phenylaminofluoran Comparative example 3: 3-diethylamino-6-methyl 7-phenylaminofluoran Seven types thus obtained The heat-sensitive recording medium was recorded using a heat-sensitive facsimile (HIFAX-700 model manufactured by Rotate), and the degree of color development of the recorded area was measured using a Maches reflection densitometer (RD-914 model). It is shown in Table 1.

Further, the whiteness of the surface of the recording layer before recording was measured using a Hunter whiteness meter, and the results are shown in Table 1.

Furthermore, in order to evaluate the chemical resistance of the recorded image, we layered a vinyl chloride film on the colored surface of the recorded heat-sensitive recording medium and left it at room temperature for 20 hours. The degree of discoloration was evaluated and the results are shown in Table 1.

"Effects" As is clear from the results in Table 1, the heat-sensitive recording material according to the present invention has high whiteness in the blank area, excellent color development and storage stability of recorded images, and the whiteness of the blank area due to the vinyl chloride film. It was an extremely excellent recording medium with no deterioration in color (background fog).

Claims (1)

[Claims] In a heat-sensitive recording material provided on a support with a heat-sensitive recording layer containing a colorless or light-colored basic dye and a coloring agent that can change color when it comes into contact with the dye, the heat-sensitive recording layer contains a colorless or light-colored basic dye as a basic dye. 3-(N-Ethyl-N-tetrahydrofurfurylamino)-6-methyl-7-phenylaminofluorane as a coloring agent of a salicylic acid derivative or its polyvalent metal salt having an aryloxyalkyloxy group as a substituent. A thermosensitive recording material characterized by containing at least one kind.