JPH0447988A - Thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a coloring characteristic, other sufficient performance, and solvent resistance by a method wherein an electron donative colorless dye containing a specific fluoran derivative, an electron acceptive compound, and a heat fusible compound containing a specific hydrocarbon compound are contained. CONSTITUTION:A thermal recording material contains an electron donative colorless dye, an electron acceptive compound, and a heat fusible compound. It contains a fluoran derivative having an alkylamino radical of which 6 position is substituted by an aryloxy radical or an arylthio radical as the electron dona tive colorless dye. Besides, it contains, at least one or more kinds of hydrocar bon compounds containing aromatic ring and/or amide and/or urea as the heat fusible compound. For the fluoran derivative as the electron donative colorless dye to be used herein, that as given by the formula [I] should be preferable. As the electron acceptive compound, a phenol derivative, an aromatic carboxylic acid metal salt, acid clay, bentonite novolak resin, etc. are used.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a heat-sensitive recording material, and more particularly to a heat-sensitive recording material in which a coloring layer containing an electron-donating colorless dye and an electron-accepting compound is provided on a support. Concerning recording materials.

(Prior Art) Recording materials using electron-donating colorless dyes and electron-accepting compounds are already well known as pressure-sensitive paper, thermal paper, light-sensitive pressure-sensitive paper, electrically conductive thermal recording paper, thermal transfer paper, and the like. For example, British Patent No. 2,140,449, U.S. Patent No. 4,48
No. 0,052, No. 4.436.920, Special Publication No. 1986
-23992, JP-A-57-179836, JP-A No. 60
-123556, 60-123557, etc. for details. In particular, heat-sensitive recording materials are detailed in Japanese Patent Publications No. 43-4160 and Japanese Patent Publication No. 45-14039.

These thermal recording systems are being applied to a wide range of fields such as facsimiles, printers, and labels, and their needs are expanding. In the past, there was a strong demand for high-speed recording, low-energy printing, head matching properties, etc., but recently, with the expansion of applications, there has been a growing demand for heat-sensitive recording materials that are highly sensitive and have excellent background preservation. There is. In particular, it is the resistance when using products that use solvents, such as adhesives such as solvent pens, diazo copying materials, and glue, which are often used as office supplies, and furthermore, the resistance in the storage state of printing, etc. In order to meet these demands, many proposals have been made, including consideration of protective layers and use of solvent-resistant color developers. However, these methods have not been able to achieve high sensitivity. In addition, the present inventors have found that solvent resistance can be imparted by using a fluoran derivative having an alkylamino group substituted with an aryloxy group or an arylthio group at the 6-position. However, I was not able to obtain sufficient sensitivity.

(Objective of the Invention) An object of the present invention is to provide a heat-sensitive recording material which has sufficient performance in various properties including coloring properties and has solvent resistance.

(Structure of the Invention) An object of the present invention is to provide a heat-sensitive recording material containing an electron-donating colorless dye, an electron-accepting compound, and a thermofusible compound, with an aryloxy group at the 6-position as the electron-donating colorless dye. Or it contains a fluoran derivative having an alkyl 7-mino group substituted with an arylthio group, and contains at least one hydrocarbon compound containing an aromatic ring and/or an amide and/or urea as a thermofusible compound. This was achieved using a heat-sensitive recording material characterized by:

The electron-donating colorless dye used in the present invention is a fluoran derivative having an arylamino group substituted with an aryloxy group or an arylthio group at the 6-position, and among them, those represented by the following format (1) are preferred.

[1] (wherein R1 and R3 are an alkyl group, an alkenyl group,
Alkynyl group, aryl group, hydrogen atom, R2 is hydrogen atom, furkyl group, alkoxy group, halogen atom, R4
is a hydrogen atom alkyl group, alkenyl group, alkynyl group,
7-aryl group, alkoxy group, aryloxy group, furkylthio group, halogen atom, substituted 7-mino group, cyano group, nitro group, acyl group, trihalomethyl group, sulfamoyl group, × represents oxygen atom or sulfur atom, Ar and The ring is an aromatic ring that may contain a heteroatom, and n is 1 to 1.
An integer of 0 and m represent an integer of 1 to 3.

The bovine santhene ring or rings may have a plurality of the same or different substituents, and in this case, the substituents represent an alkoxy group, a halogen atom, or a nitro group.

The group represented by R1 in the above-format [1] further includes a furkyl group, an alkenyl group, an alkynyl group, an aryl group,
It may be substituted with an alkoxy group, an aryloxy group, an alkylthio group, a halogen atom, a substituted amino group, a cyano group, a nitro group, a 7-syl group, a trihalomethyl group, a sulfamoyl group, a Hege O-ring residue, or the like. These substituents may further have a substituent. As R1, H-CHzl-C-R2, -IYZ.

-CIl R2, -), -〇. R2,OC,R2,-
,YZ.

(n is an integer from 2 to 10, m is an integer from 1 to 5, Y and 2
is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, a halogen atom, a substituted amino group, a cyano group,
Indicates a nitro group, acyl group, trihalomethyl group, sulfamoyl group, and hetero residue. ) is preferred.

Particularly preferred R is a methyl group, ethyl group, propyl group, butyl group, or the like.

In the above formula, the group represented by R2 is preferably an alkyl group, an alkenyl group, a furkynyl group, an alkoxy group, or a halogen atom, and particularly a methyl group, an ethyl group, a methoxy group, a methoxymethyl group, a methylthio group, or a chlorine atom.

In the above formula, the group represented by R3 is a hydrogen atom, and has 1 to 1 carbon atoms.
8 is preferable, and a hydrogen atom and an ethyl group are particularly preferable.

R4 is preferably a hydrogen atom, an alkyl group, a heptadyl group, an alkoxy group, or an alkenyl group, and may further have a substituent such as a halogen atom or an alkoxy group.

1 to 3 R4s can be substituted on the benzene ring, and in the case of multiple R4s, they may be the same or different.

When R3 is a hydrogen atom, R4 is preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. When R1 is an ethyl group, R4 is preferably a trifluoromethyl group, a nitro group, a cyano group, a sulfamoyl group, or the like.

In the above formula, the ring is preferably a benzene ring, a naphthalene ring, a pyridine ring, a birimidazine ring, an indole ring, etc., and a benzene ring is particularly preferred.

When ring A is substituted with the same or different substituents, the substituent is preferably a halogen atom, a nitro group, a cyano group, an alkoxy group, etc., and a chlorine atom or a fluorine atom is particularly preferable.

The aromatic ring represented by Ar in the above formula is preferably a benzene ring, a naphthalene ring, a pyridine ring, a furan ring, a coumarin ring, etc., and a benzene ring or a naphthalene ring is particularly preferred.

As a substituent for Ar, a saturated or unsaturated furkyl group,
Dichlorofurkyl group, 7-lyl group, hydroxy group, alkoxy group, furkisthio group, 7-lyloxy group, arylthio group, halogen atom, dialkyl 7m8L carbonyl group, carboxyl group, carboxyl group, carbamoyl group, flukoxycarbonyl group, Preferable examples include a 7-syl group, a cyano group, a nitro group, a sulfonyl group, an isocyanate group, and a heterocyclic residue. These substituents may further have similar substituents; for example, for a furkyl group,
Examples include a flukoxyfurkyl group, a halofurkyl group, an aralkyl group, and a hydroxyphenyl-substituted furkyl group. Furthermore, the molecule may contain several phenolic compounds via substituents.

In particular, substituents for Ar include methyl group, ethyl group, isopropyl group, t-butyl group, benzyl group, methoxymethyl group, phenoxymethyl group, cyclohexyl group, methoxy group, ethoxy group, phenoxymethoxy group, phenoxyethoxy group, Phenoxypropoxy group, chloroethoxy group, methylthio group, ethylthio group, phenylthioethoxy group, phenoxy group, nylthio group, phenoxyethylthio group, acetyl group, 7-cetoxy group, methoxycarbonyl group, diano group, formyl group, trifluoromethyl A diethyl 7-mino group, a chlorine atom, a fluorine atom, and the like are preferred.

In the above -format [1], n is preferably an integer of 2 to 6, and the divalent group represented by -(CH,) or - may be linear or branched.

Specific examples of the fluoran derivatives according to the present invention are as follows:
-7nilino3-methyl-6-N-ethyl-N-(2-
phenoxyethyl)aminofluorane, 2-7nilino3-methyl-6-N-ethyl-N-(3-phenoxypropyl)7minofluorane, 2-7nilino3-methyl-6-N-ethyl-N-(3 -(4-methoxyphenoxy)propyl)7minofluorane, 2-7nilino3-
Methyl-6-N-ethyl-N-(3-(4-methylthiophenoxy)propyl)aminofluorane 2-7nilino3-methyl-6-N-ethyl-N-(3-L4-methoxyphenylthio) propyl) aminofluorane, 2
-7nilino3-methyl-6-N-ethyl-N-(3-
(3-methylphenoxy)propyl) 7 minowalorane, 2-7 dilino 3-methyl-6-N-ethyl-N-
3-(3,5-difluorophenoxy)propyl]aminofluorane, 2-7nilino3-methyl-6-N-ethyl-N-[3-(2-naphthyloxy)butyl]7
Minofluorane, 2-7nilino-3-methyl-6-N-
Ethyl-N-(3-(4-(2-phenoxyethoxy))
phenoxidinepropyl)aminofluorane, 2-p-ethylanilino-3-methyl-6-N-ethyl-N-(2
-(4-methoxy-1-naphthyloxy)ethyl]7minofluorane, 2-N-methyl-N-(3-trifluoromethylphenyl)aminofluorane.

2-N-ethyl-N-(2,4-dimethyl7mino)-6
-N-Ethyl-N-(3-(4-methylthiophenoxy)buOvir]7minofluorane.

2-7nilino3-methyl-6-N-ethyl-N-)2
- (4-(4-methoxyphenoxy)phenoxy)ethyl)7minofluorane, 2-7nilino3-methyl-
6-N-ethyl-N-(2-(2-methylphenoxy)
ethyl)aminofluorane, 2-7nilino3-methyl-6-N-ethyl-N-(2-(3-methylphenoxy)ethyl)aminofluorane, 2-7nilino3-methyl-5-N-ethyl -N-(2-(4-methylphenoxy)ethyl)7minofluorane, 2-7dilino3-methyl-5-N-ethyl-N-(2-(2-ethylphenoxy)ethyl)7minofluorane, 2- 7 Nilino 3-
Methyl-6-N-ethyl-N-(2-(3-ethylphenoxy)ethylcoaminofluorane, 2-7 Nilino 3
-Methyl-6-N-ethyl-N-(2-(4-ethylphenoxy)ethyl)7minofluorane, 2-7nilino3-methyl-6-N-ethyl-N-(2-(2-methoxyphenoxy)) Ethylcoaminofluorane, 2-7 Nilino 3-methyl-6-N-ethyl-N-(2-(3-methoxyphenoxy)ethyl)aminofluorane, 2-7
Nilino 3-methyl-6-N-ethyl-N-(2-(4
-methoxyphenoxy)ethyl)aminofluorane, 2
-7nilino3-methyl-6-N-ethyl-N-(2-
(3,5-difluoro[znoxy)ethyl)aminofluorane, 2-7nilino3-methyl-6-N-ethyl-
N-(2-(4-fluorophenoxy)ethyl)aminofluorane, 2-7nilino-3-methyl-6-N-ethyl-N-(2-(4-fluorophenoxy)ethyl)aminofluorane, 2-7 Nilino 3-methyl-6-N-ethyl-N-(2-(4-methylthiophenoxy)ethyl)7minofluorane, 2-7 Nilino 3-methyl-6-
N-ethylthio(2-(4-ethylthiophenoxy)
ethyl) aminofluorane.

2-7 Nilino 3-methyl-6-N-ethyl-N-(4
-(4-ethylphenoxy)butyl]7minofluorane,
2-7 Nilino 3-methyl-6-N-ethyl-N-(1
-methyl-2-phenoxyethyl)aminofluorane,
2-7 Nilino 3-methyl-6-N-ethyl-N-(4
-(4-methoxyphenoxy)butyl]7minofluorane, 2-7nilino3-methyl-6-N-ethyl-N-
(4-(3-methylphenoxy)butyl)aminofluorane, 2-7nilino-3-methyl-6-N-ethyl-N
-(2-(2-methylphenoxy)ethyl)7minofluorane, 2-7nilino3-methyl-6-N-ethyl-
N-(2-(2-methylphenoxy)ethylcoaminofluorane, 2-p-ethyl7nilino3-methyl-6-
N-ethyl-N-(2-(4-ethylphenoxy)ethyl)7minofluorane, 2-N-methyl-N-(3-trifluoromethylphenyl)7mino6-N-ethyl-
N-(2-(2-ethylphenoxy)ethyl)aminofluorane, 2-ethyl-(2,4-dimethylphenyl)
7 minnow 6-N-(2-(4-methoxyphenoxy)ethyl) 7 minofluorane, 2-7 nilino 3-methyl-
6-N-tetrahydrofurfuryl-N-(2-(4-ethylphenoxy)ethyl)7minofluorane.

2-7 Nilino 3-methyl-6-N-tolyl-N-(2
-(4-ethylphenoxy)ethyl]7minofluorane, 2-7nilino3-methyl-6-N-SchifOhexyl-N-(2-(4-ethylphenoxy)ethyl)aminofluorane, 2-7 Rino-3-methoxy-6-N-ethyl-N-(2-(4-ethylphenoxy)ethyl)7
Minofluorane, 2-7nilino-3-chloro-6-N-
Ethyl-N-(2-(4-ethylphenoxy)ethyl)
7minofluorane, 2-7nilino-3-n-hexyl-
6-N-ethyl-N-(2-(4-ethylphenoxy)
ethyl)aminofluorane, 2-(2,4-dimethyl)
Anilino-3-methyl-6-N-ethyl-N-(3-
(4-ethylphenoxy)ethyl)7minofluorane,
2-o-fluoro7nilino3-methyl-6-N-ethyl-N-(3-(4-ethylphenoxy)buOpyr)aminofluorane+2 o-chloro7nilino3-methyl-6-N-ethyl -N-(3-(4-ethylphenoxy)buOpyr)7minofluorane.

2-7 Nilino 3-methyl-6-N-ethyl-N-(2
-phenoxyprovir) 7minofluorane, and the like.

The electron-donating colorless dyes according to the present invention include conventionally known triphenylmethane compounds, fluoran compounds, phenothiazine compounds, indolylphthalide compounds, leucoauramine compounds, rhodamine lactam compounds, and triphenylmethane compounds. compounds, triazene compounds,
It can be used in combination with various compounds such as spiropyran compounds and fluorene compounds.

Specific examples of phthalides are given in U.S. Patent Reissue Patent Specification 1i No. 2.
No. 3024, US Pat. No. 3,491,111, US Pat. No. 3,491,112, US Pat.
No. 09174, specific examples of fluorans are U.S. Patent Specifications No. 3,624,107, U.S. Pat.
No. 41011, No. 3462828, No. 36813
No. 90, No. 3920510, No. 3959571, and specific examples of spiropyrans are U.S. Patent Specification No. 39718.
No. 08, pyridine-based and pyrazine-based compounds are described in US Pat. No. 3,776,424, US Pat. No. 3,853,869, and US Pat.

The electron-accepting compound used in the present invention includes phenol derivatives, metal salts of aromatic carboxylic acids, acid clay, bentonite, novolac resins, metal-treated novolac resins, metal complexes, and the like. These examples are
No. 09, JP 45-14039, JP 52-14
No. 0483, JP-A-48-51510, JP-A-57-
No. 210886, JP-A-58-87089, JP-A-Sho 5
9-11286, JP-A-60-176795, JP-A-61-95988, etc.

To give some examples of these, phenolic compounds include 2,2'-bis(4-hydroxyphenyl)propane, 4-phenylphenol, and 1,1-bis(3-chloroo-4-hydroxyphenyl). Cyclohexane, 1
．． 1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(3-chloro-4-hydroxyphenyl)-2-ethylbutane, 4.4″-5ec-inoctylidene diphenol, 4,4′-5ec -butylidene diphenol, 4-p-methylphenylphenol,
4.4'-Methylschif-O hexylidenephenol, 4゜4'-isopentylidenephenol, bis(3-7ly-4-hydroxyphenyl)sulfone, 4-hydroxyphenyl-3゛4° dimethylphenylsulfone, 4
-(4-isobuOboxyphenylsulfonyl)phenol, bis(2-(4-hydroxyphenylthio)ethoxy)methane, benzyl P-humanOoxybenzoate, and the like. Salicylic acid derivatives include 4-pentadecylsalicylic acid, 3,5-di(α-methylbenzyl)salicylic acid, 3
．． 5-di(ter-octyl)salicylic acid, 5-α-(
p-α-methylbenzylphenyl) ethylsalicylic acid, 3-α-methylbenzyl-5-tar-octylsalicylic acid, 5-tetradecylsalicylic acid, 4-hexyloxysalicylic acid, 4-SchiffO hexyloxysalicylic acid, 4-decyl Examples include oxysalicylic acid, 4-dodecyloxysalicylic acid, 4-pentadecyloxysalicylic acid, 4-octadecyloxysalicylic acid, and their salts such as zinc, aluminum, calcium, and copper. Among these, bisphenols are preferred.

The amide compound according to the present invention is represented by the following general formula (11), and the urea compound is represented by the following general formula (III).

RI CON HR2 (II) R3-NHCONH2 (II+) (RI R3 is an alkyl group that may have a substituent,
R3 is a hydrogen atom or a phenyl group, R4 is an alkyl group, which may be a phenyl group, and n is 1 to 5.
indicates an integer. ) Specific examples of general formulas (11) to (IV) include methylolstearylamide, stearic acid amide, palmitic acid amide, tetrasuccinic acid amide, N-phenylstearic acid amide, N-phenylpalmitic acid amide, N-stearylurea, Examples include N-balmitylurea and p-benzylbiphenyl.

Next, a typical method for producing a heat-sensitive coloring layer of the present invention will be described.

The electron-donating colorless dye, the electron-accepting compound, and the sensitizer are dispersed to a size of several microns or less together with an aqueous solution of a water-soluble polymer such as polyvinyl alcohol using a ball mill, sand mill, or the like. The sensitizer is added to either the electron-donating colorless dye or the electron-accepting compound, or both, and is dispersed simultaneously, or in some cases, a eutectic product is prepared in advance with the electron-donating colorless dye or the electron-accepting compound. , may be dispersed.

These dispersions are mixed after dispersion, and pigments and
Add surfactant, binder, metal soap, wax, antioxidant, ultraviolet absorber, etc. to make a heat-sensitive coating liquid. The obtained heat-sensitive coating liquid is coated and dried on high-quality paper, high-quality paper with an undercoat layer, synthetic paper, plastic film, etc., and then smoothed by calendering to obtain the desired heat-sensitive recording material.

At this time, the smoothness specified by JIS-8119 is 500.
From the viewpoint of dot reproducibility, it is particularly preferable to use a support that lasts for at least 80 seconds, particularly for at least 800 seconds. To obtain a support with a smoothness of 500 seconds or more, ■ Use something with high smoothness such as synthetic paper or plastic film ■ Provide an undercoat layer containing pigment as the main component on the support ■ Super Calender There are methods such as increasing the smoothness of the support by using .

The binder is preferably a compound that dissolves 5% by weight or more in water at 25°C, and specifically, polyvinyl alcohol (including modified polyvinyl alcohols such as carboxy-modified, itaconic acid-modified, maleic acid-modified, and silica-modified polyvinyl alcohols). , methylcellulose, carboxymethylcellulose, starches (including modified starches), 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 coating film strength. , methyl acrylate-butadiene copolymer, and synthetic polymer latex binder such as polyvinylidene chloride can also be used in combination.

Further, a crosslinking agent suitable for the binder may be added depending on the type of the binder, if necessary.

Pigments include calcium carbonate, barium sulfate, lithopone, waxite, kaolin, silica, amorphous silica, and the like.

As the metal soap, higher fatty acid metal salts are used, such as zinc stearate, calcium stearate, aluminum stearate, and the like.

Furthermore, surfactants, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, fluorescent dyes, coloring dyes, etc. may be added as necessary.

The coated heat-sensitive recording material is dried and subjected to a process such as a calender before being used.

Further, a protective layer may be provided on the heat-sensitive coloring layer if necessary. As the protective layer, any one known as a protective layer for heat-sensitive recording materials can be used.

Furthermore, if necessary, a back coat layer may be provided on the opposite side of the support of the heat-sensitive recording material from the heat-sensitive coloring layer. As the back coat layer, any material known as a back coat layer for thermal recording materials can be used.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited only to the Examples below.

(Example-1) 2-7nilino3-methyl-6-N-ethyl-N-(3-methylphenoxypropyl)7minofluoran as an electron-donating colorless dye Bisphenol A as an electron-accepting compound, a thermofusible compound Each of methylolster-7lylamide and 209 was dispersed with a 5% aqueous solution of polyvinyl alcohol (Kuraray PVA-105) of 1009 in a ball mill for one day and night, and the average particle size was adjusted to 1.5 μm or less to obtain each dispersion. Further, calcium carbonate 809 was dispersed with a 0.5% sodium hexametaphosphate solution 1609 using a homogenizer to obtain a pigment dispersion.

Each of the dispersions prepared as described above was mixed with 59 parts of an electron-donating colorless dye dispersion, 109 parts of an electron-accepting compound dispersion, 109 parts of a β-naphthylbenzyl ether dispersion, and 59 parts of a calcium carbonate dispersion. A heat-sensitive coating liquid was obtained by adding 39% zinc stearate emulsion. This heat-sensitive coloring layer coating solution was applied onto a high-quality paper with a basis weight of 509/m2 using a wire bar so that the dry overlap of the coated layer was 59 ft, and was dried at 50°C for 1 minute to obtain heat-sensitive recording paper. Ta.

(Example-2) Instead of methylolstearylamide in Example-1,
A heat-sensitive recording material was obtained in the same manner as in Example-1 except that stearyl urea was used.

(Example-3) Instead of methylolstearylamide in Example-1,
A heat-sensitive recording paper was obtained in the same manner except that p-benzylbiphenyl was used to prepare the heat-sensitive coating liquid.

(Example-4) 2-7nilino-3-methyl-6-N-(4
-methoxyphenoxypropyl)aminofluorane instead of 2-7nilino3-methyl-6-N-ethyl-
A heat-sensitive recording material was obtained in the same manner as in Example 1 except that N-(3-methylphenoxypropyl)aminofluorane was used.

(Comparative Example-1) A heat-sensitive recording material was obtained in the same manner as in Example 1, except that the methylolster-7-lylamide of Example 1 was not used.

(Comparative Example-2) Instead of 2-7nilino-3-methyl-6-N-ethyl-N-(4-methoxyphenoxypropyl)7minofluorane in Example-1, 2-7nilino-3-methyl-6-
Example-1 except that dinityl 7minofluorane was used
A heat-sensitive recording material was obtained in the same manner as above.

(Comparative Example-3) In place of methylolstefurylamide in Example-1, p
A heat-sensitive recording material was obtained in the same manner as in Example-1 except that -hydroxymethylbenzyl ester was used.

The surface of the thermal recording paper obtained as described above was treated with a calender, and the smoothness was 300±5 as Beck smoothness.
The temperature was adjusted to 0 seconds to obtain a heat-sensitive recording material.

The thermal recording paper was evaluated as follows.

■Color density was determined by Kyocera printing tester at printing energy of 30.
The color density was measured using a Macbeth densitometer using mJ/mm'. The higher this value is, the higher the sensitivity of the thermal recording paper is.

■For heat resistance evaluation, the density of the white background area and the density of the printed area (printed with a Kyocera printing tester) with a color development density of 1.3 were measured using a Macbeth densitometer after being left at 60" 30% RH for 24 hours. .Those with low density in the white background area and high density in the printed area have a high shelf life.

(2) For chemical resistance evaluation, ethanol Q, LCC was dropped onto the heat-sensitive recording material using a dropper, and fogging was visually evaluated as follows.

Q: No fogging: x: Fogging: As can be seen from the results in Table 1, the heat-sensitive recording material of the present invention has high sensitivity, and the storage stability of the white background area and printed area under high temperature storage conditions. It can be seen that this is a heat-sensitive recording material with good chemical resistance.

Claims (1)

[Claims] In a heat-sensitive recording material containing an electron-donating colorless dye, an electron-accepting compound, and a thermofusible compound, the electron-donating colorless dye has an alkylamino group substituted with an aryloxy group or an arylthio group at the 6-position. 1. A heat-sensitive recording material characterized in that it contains a fluoran derivative having the following properties, and at least one hydrocarbon compound containing an aromatic ring and/or amide and/or urea as a thermofusible compound.