JPS62160279A - Thermal recording material - Google Patents

Abstract

PURPOSE:To contrive not only to enhance color developability but also to improve the whiteness of a back ground part, in a thermal recording material utilizing color forming reaction between a colorless or light colored electron donating dye and a coupler thereof, by using a specific solvent inclusion complex as a color forming promoter. CONSTITUTION:If a solvent inclusion complex containing a compound represented by general formula (I) (wherein X and Y are a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group or an acetyl group) or a compound represented by general formula (II) [wherein Ar is A (wherein n is an integer of 1-3) or B (wherein X is halogen and m is an integer of 1-2)] as a host molecule is used as a color forming promoter in the color forming reaction between an electron donating dye and a coupler thereof, color developability is enhanced and, further, whiteness is also improved. The host molecule represented by each of the general formulae (I), (II) forms the solvent inclusion complex of which the mol ratio with a solvent is 1:1 or 1:2 and has high solvent including capacity and said complex is stable in usual but decomposed under heating to release a large amount of the solvent. This solvent inclusion complex can be simply prepared by generally adding the host molecule to the solvent and separating the precipitated inclusion complex to dry the same.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a heat-sensitive recording material that records by causing a colorless or light-colored electron-donating dye and its color developer to undergo a color-forming reaction with heat, and is particularly suitable for high-speed recording. The present invention relates to a heat-sensitive recording material with high whiteness and excellent color development.

[Prior art]

A thermosensitive recording material is a material in which a thermosensitive coloring layer capable of forming a colored image by heating is provided on a support such as paper, and a thermal printer equipped with a thermal head is widely used for heating.

These conventional heat-sensitive recording materials include a colorless or light-colored electron-donating dye having a lactone ring, a lactam ring, a spiropyran ring, etc. in the heat-sensitive coloring layer, and a developing color that develops color by reacting with the electron-donating dye when heated. Many are used that contain agents.

In this heat-sensitive recording method, an electron-donating dye and a color developer are contained in a binder in the form of fine particles, which are melted by heat and come into contact with each other to cause a color reaction.
For this reason, to improve thermal sensitivity, there are methods to use electron-donating dyes and color developers with low melting points so that they melt with small energy, methods to use sensitizers that take advantage of lowering the melting point due to half-melting, and materials. Methods have been put into practical use to improve contact by making particles finer, but these methods have not been sufficient as high-speed heat-sensitive recording materials. For example, JP-A-53-3
No. 9139, JP-A-53-26139, JP-A-53-
No. 5636, JP-A-53-11036, etc., further contain various waxes, fatty acid amides,
It has been proposed to add a heat-melting substance with a low melting point, such as alkylated biphenyls, substituted biphenylalkanes, coumarins, and diphenylamines, as a sensitizer (or melting point depressant). However, in the method of adding a sensitizer, it is necessary to melt the sensitizer before the color reaction occurs, so it is difficult to obtain sufficient thermal response in high-speed recording where only a small amount of heat is supplied in a short pulse. However, since the sensitizer in the coloring layer melts, there are problems with recording suitability such as adhesion of residue to the thermal head, smearing, trailing, ghosting, and other problems. Furthermore, when stored at high temperatures and/or high humidity, fogging occurs over time and often reduces the contrast of recorded images. Therefore, it is desirable that a heat-sensitive recording sheet for high-speed recording has a structure in which no sensitizer is added.
Since the temperature is as high as 0°C, in order to construct a heat-sensitive color forming layer suitable for high-speed recording without adding a sensitizer, it is essential to use a color developer that has a low melting point and has a high ability to develop color from the color former. . By the way, acidic substances, especially phenolic compounds, to be used in combination with colorless or light-colored dyes are described in various documents, including Japanese Patent Publication No. 45-14039, but among these, bisphenol A is known for its quality stability, It is widely used due to its low price and easy availability. However, this bisphenol A has a melting point of 156-15
Since the temperature is as high as 8° C., it has the disadvantage of low thermal sensitivity (and therefore high thermal coloring temperature). In contrast, phenolic compounds with low melting points, such as 4-t,-butylphenol (melting point 94-99°C), α-naphthol (melting point 95-96°C),
), β-naphthol (melting point: 119-122°C), etc., the storage stability of the heat-sensitive recording sheet is poor, and not only does fogging gradually occur even at room temperature, but it also has a strong so-called phenol odor, making it difficult to put into practical use. Not the point.

In addition, 2,2-bis (4
'-Hydroxyphenyl) normal hexane (melting point 9
9-103℃), and 1, in JP-A-55-27253
It has been described that a heat-sensitive recording sheet with high heat sensitivity, storage stability, and color development can be made using each of 1-bis(4'-hydroxyphenyl) alkanes (alkanes have 3 to 13 carbon atoms). However, all of these substances are difficult to synthesize and have problems in availability. Furthermore, JP-A-5
No. 6-144193 describes that lower alkyl esters or benzyl esters of p-hydroxybenzoic acid are easy to synthesize and can be used to make highly sensitive heat-sensitive recording sheets. has disadvantages in terms of storage, such as the colored part tends to fade over time and crystals of the phenolic compound precipitate (so-called white powder phenomenon). Also, JP-A No. 59-101392,
JP-A-59-101393, JP-A-59-22793
No. 1, etc. proposes a method in which a low-molecular compound is added to the heat-sensitive recording layer to lower the melting point by eutecticization with a leuco dye or color developer, but this method causes a fogging phenomenon. Therefore, the melting point of the leuco dye or color developer cannot be lowered too much, and there is a limit to increasing the sensitivity, and the structure of the low-molecular organic compound used is also limited, so it is difficult to ensure that the effect is sufficient. No, no. Furthermore, JP-A-58-21
No. 7390 discloses that 1.1-G (4'-
It has been proposed to add a low-molecular-weight organic compound clathrate of (hydroxyphenyl)-cyclohexane, but with this method, it is difficult to sufficiently improve sensitivity because the amount of organic compound that can be clathrated is small. Ta.

As described above, conventional heat-sensitive recording sheets for high-speed recording have advantages and disadvantages, whether they use a sensitizer or melting point depressant or not, and none of them can be said to be practical.

〔the purpose〕

An object of the present invention is to provide a heat-sensitive recording material which, unlike the conventional heat-sensitive recording materials, has significantly improved color development and excellent whiteness of the background portion.

〔composition〕

According to the present invention, in a heat-sensitive recording material that utilizes a color-forming reaction between a colorless or light-colored electron-donating dye and its color developer, the following general formula (1) or the following general formula (II) is used as a color development accelerator. Provided is a heat-sensitive recording material characterized by using a solvent inclusion complex having a compound represented by the following as a host molecule.

(In the formula, X and Y represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or an acetyl group.) Rogen and m represent an integer of 1 to 2. ). ] The present inventor believes that the color-forming reaction between the electron-donating dye and the color developer occurs when the electron-donating dye or the color developer is in a dissolved state, or
Focusing on the fact that these substances develop a color when dissolved in a solvent, compounds of the above general formula (1) or general formula (■), which are usually stable and release a large amount of solvent when heated, are used as color development accelerators. The present inventors have discovered that when a solvent inclusion complex is used as a host molecule, color development is improved and whiteness is further improved, and the present invention has been completed.

The host molecules represented by the general formula (I) and general formula (II) used in the present invention have a molar ratio of 1:1 or 1:2 to the solvent.
It forms a solvent inclusion complex and has a high solvent inclusion ability, and is normally stable, but when heated, it decomposes and releases a large amount of solvent. This solvent inclusion complex can generally be easily produced by adding a host molecule to a solvent and separating and drying the precipitated inclusion complex.

The solvent inclusion complex of the host molecule of general formula (1) and the solvent is
For example, it is produced by first synthesizing the host molecule of general formula (1) by reacting propynyllithium with the corresponding ketone, then adding it to a guest solvent and allowing the reaction to occur at room temperature and pressure.

Further, the solvent inclusion complex of the host molecule of the general formula (II) and the solvent can be obtained, for example, by subjecting P-benzoxin and a corresponding benzene derivative to a Friedel-Crafts reaction to obtain a phos 1-molecule of the general formula (■); Next, this product is added to a guest solvent, heated and dissolved, left at room temperature, and then filtered to produce the product.

Examples of the guest solvent used in the present invention include those that are soluble in electron-donating dyes and/or color developers, such as aromatic hydrocarbons, halogenated hydrocarbons, alcohols, ketones, phenols, and esters. Alcohols that have high inclusion properties with host molecules are particularly preferably used.

Specific examples of the solvent inclusion complex used in the present invention include those shown in Table I below.

The blending ratio of the solvent inclusion complex used in the heat-sensitive recording layer is generally in the range of 0.1 to 6 parts by weight, preferably 1 to 4 parts by weight, per 1 part by weight of the electron-donating dye.

The electron-donating dyes used in the present invention may be applied singly or in a mixture of two or more, and as such electron-donating dyes, those applied to this type of heat-sensitive material may be arbitrarily applied, such as , triphenylmethane-based, fluoran-based, phenothiazine-based, auramine-based, spiropyran-based dyes, and the like are preferably used. Specific examples of such electron-donating dyes include those shown below.

3.3-bis(P-dimethylaminophenyl)-phthalide, 3.3-bis(P-dimethylaminophenyl)-6-dimethylaminophthalide (also known as crystal violet lactone), 3.3-bis(p- dimethylaminophenyl)-6-dibutylaminophenyl, 3.3-bis(ρ-dimethylaminophenyl)-6-chlorophthalide, 3.3-bis(p-dibutylaminophenyl)phthalide, 3-cyclohexylamino-6- Chlorfluorane, 3-dimethylamino-5,7-dimethylfluorane, 3
-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-7,8-benzfluorane, 3-diethylamino-6
-Methyl-7-chlorofluorane, 3-(N-p-tolyl-N-ethylamino)-6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2- (N-(3'-trifluoromethylphenyl)
amino)-6-dinithylaminofluorane, 2-(3,
6-bis(diethylamino)-9-(o-chloroanilino)xantylbenzoic acid lactam), 3-diethylamino-6-methyl-7-(m-trichloromethylanilino)fluoran, 3-diethylamino-7-(o-chloroanilino) ) fluoran, 3-dibutylamino-7-(0-chloroanilino)fluoran, 3-N-methyl-N-amylamino-6-methyl-7-
Anilinofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-(N,N- diethylamino)-5-methyl-7-(
N.

N-dibenzylamino)fluoran, benzoylleucomethylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrylospirane, 6'-bromo-3'-methoxy-benzoindolino-pyrylospirane, 3-(2'- 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-41-chloro-5'
-methylphenyl)phthalide, 3-morpholino-7-(N-propyl-trifluoromethylanilino)fluorane, 3-pyrrolidino-7-1-lifluoromethylanilinofluorane, 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)fluoran.

3-diethylamino-7-(0-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7-(α-phenylethylamino)fluoran, 3-diethylamino-7-piperidinofluorane.

2-chloro-3-(N-methyltoluidino)-7-(p
-n-butylanilino)fluorane, 3-(N-benzyl-N-cyclohexylamino)-5
, 6-penzo 7-α-naphthylamino-4'-bromofluorane, 3-diethylamino-6-methyl-7-mesitidino 4
',5'-benzofluorane etc.

Further, as the color developer used in the heat-sensitive coloring layer of the present invention, various electron-accepting substances that react with the electron-donating dye to color it when heated are applied, and specific examples thereof include: Examples include phenolic substances, organic or inorganic acidic substances, and salts thereof as shown below.

gallic acid, salicylic acid, 3-isopropylsalicylic acid,
3-cyclohexylsalicylic acid, 3,5-di t,e
rt-butylsalicylic acid, 3,5-di-α-methylbenzylsalicylic acid, 4,4'-isopropylidene diphenol, 4,4'-isopropylidene bis(2-chlorophenol), 4,4'-isopropylidene bis (2,6
-dibromophenol), 4.4'-isopropylidene bis(2,6-dichlorophenol), 4.4'-isopropylidene bis(2-methylphenol), 4.4'
-isopropylidene bis(2,6-dimethimephenol), 4,4'-isopropylidene bis(2-tart,
-butylphenol), 4,4'-5ec-butylidene diphenol, 4,4'-cyclohexylidenebisphenol, 4,4'-cyclohexylidenebis(2-
Methylphenolphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, 3
, 5-xylenol, thymol, methyl-4-hydroxybenzoate, 4-hydroxyace1-phenone, novolac type phenolic resin, 2,2'-thiobis(4,
6-dichlorophenol), catechol, resorcinol,
Hydroquinone, pyrogallol, phloroglycine, phloroglycin carboxylic acid, 4-t,crt,-octylcatechol, 2,2'-methylenebis(4-chlorophenol), 2,2'-methylenebis(4-methyl-6-t)
ert, -butylphenol), 2゜2'-dihydroxydiphenyl, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, p-hydroxybenzoate-P- Chlorbenzyl, p-hydroxybenzoic acid-6M-0-chlorobenzyl, p-hydroxybenzoic acid-
P-methylbenzyl, n-octyl P-hydroxybenzoate, benzoic acid, zinc salicylate, 1-hydroxy-
2-naphthoic acid, 2-hydroxy-6-naphthoic acid, 2
-Zinc hydroxy-6-naphthoate, 4-hydroxydiphenylsulfone, 4-hydroxy-4'-chlorodiphenylsulfone, bis(4-hydroxyphenyl)sulfide, 2-hydroxy-p-toluic acid, 3.5-di-tart -Zinc butylsalicylate, 3,5-di-te
rt: -tin butylsalicylate, tartaric acid, oxalic acid, maleic acid, citric acid, succinic acid, stearic acid, 4-hydroxyphthalic acid, boric acid, etc.

In the present invention, the ratio of the electron-donating dye and color developer used in the thermosensitive coloring layer is as follows:
The proportion of the color developer is 0.1 to 5.0 parts by weight, preferably 1 to 4 parts by weight.

In the present invention, in order to bind and support the electron-donating dye and color developer on the support, various commonly used binders can be used as appropriate, such as polyvinyl alcohol, starch and its derivatives, methoxycellulose, etc. , cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, and acrylic amide/acrylic ester copolymers.

Acrylic acid amide/acrylic acid ester/methacrylic acid terpolymer, styrene/maleic anhydride copolymer alkali salt, inbutylene/maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein, etc. In addition to water-soluble polymers, polyvinyl acetate,
Polyurethane, styrene/butadiene copolymer, polyacrylic acid, polyacrylic ester, vinyl chloride/vinyl acetate copolymer, polybutyl methacrylate, ethylene/vinyl acetate copolymer, styrene/butadiene/acrylic copolymer, etc. Latex etc. can be used.

In addition, in the present invention, in addition to the electron-donating dye and color developer, if necessary, auxiliary additive components commonly used in this type of heat-sensitive recording material, such as fillers, surfactants,
In addition to the thermofusible substance (or lubricant), an ultraviolet absorbing agent, a water resistant agent, a dispersing agent, a color erasing agent, etc. can be used in combination. In this case, fillers include, for example, calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, talc, and surface-treated inorganic fine powders such as calcium and silica. Examples of thermofusible substances include organic fine powders such as urea-formalin resin, styrene/methacrylic acid copolymer, and polystyrene resin.

In addition to higher fatty acids or their esters, amides, or metal salts, various waxes, condensates of aromatic carboxylic acids and amines, phenyl benzoate, higher linear glycols, dialkyl 3,4-epoxy-hexahydrophthalates , higher ketones, other thermofusible organic compounds, etc.
Examples include those having a melting point of about 200°C.

The heat-sensitive recording material of the present invention includes (1) an electron-abrasive dye added to an aqueous solution containing a binder such as polyvinyl alcohol as described above;
A suspension is prepared by separately dispersing the color developer and the solvent inclusion complex using a dispersing machine such as a ball mill, attritor, or sand mill, and the above-mentioned auxiliary additive components are added as necessary. The suspensions thus obtained were mixed to form a coating solution.

It is manufactured by coating on a suitable support such as paper, synthetic paper, plastic film, etc. and drying it.

It is applied to various recording fields.

〔effect〕

The heat-sensitive recording material of the present invention has the above-described structure, and uses a solvent inclusion complex having the compound of the general formula (1) or the general formula (■) as a host molecule as a color development accelerator.
It has excellent heat sensitivity and improved whiteness in the background area.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Note that both parts and percentages are based on weight.

Example 1 -INQI 9-(1-propynyl)-fluoren-9-ol 50
1 part was added to 50 parts of methanol, left at room temperature for 6 hours, and centrifuged to obtain a 1:1 complex. This complex was colorless and prismatic and had a melting point of 51-58°C.

Solvent inclusion complex as described above 20 parts 2.2
-Bis(4'-hydroxyphenyl)propane 0II Hydroxyethyl cellulose 10% water m Solution 4 Q u
water
601/B liquid formulation 3-(N-methyl-N-cyclohexylamino)-6-
Methyl-7-anilite fluorane 20 parts Hydroxyethyl cellulose 10% aqueous solution 20 Il water
601
1 difference] 1 way ~ Calcium carbonate 20 parts Methyl cellulose 5% aqueous solution 20 I/water
A mixture of each of the above formulations was pulverized and dispersed in a magnetic ball mill for 2 days to obtain 20 parts of liquid A, 10 parts of liquid B, and 3 parts of liquid C.
0 parts and 20% of isobutylene maleic anhydride copolymer
10 parts of an alkaline aqueous solution were mixed, and the resulting coating liquid was applied to a commercially available high-quality paper with a basis weight of 50 g/cut using a wire bar to a dry coating weight of 5 g/cut, and dried to prepare a heat-sensitive recording sheet.

Example 2 50 parts of 9-(1-propynyl)-fluoren-9-ol (Table INα2) was added to 50 parts of tert-butanol, left at room temperature for 6 hours, and centrifuged. :1 complex was obtained.

This complex was in the form of plain prisms and had a melting point of 62-69°C.

A liquid formulation 20 parts of the above solvent inclusion complex Benzyl p-hydroxybenzoate 20! ! Hydroxy engineered cellulose 10% aqueous solution 40/I water
60/I
l 3-(N-diethylamino)-6-methyl-20 parts 7-
Anilitufluoran hydroxyethylcellulose 10% aqueous solution 201I water
A mixture of each of the above formulations, which is the same as the C liquid formulation in Example 1, was prepared in a magnetic ball mill in the same manner as in Example 1 to prepare a coating liquid and prepare a heat-sensitive recording sheet.

Example 3 -1 NL14 2-methyl-9-(1-propynyl)-fluorene-9
50 parts of -ol was added to 50 parts of ethanol, left to stand at room temperature for 6 hours, and centrifuged to obtain a 1:1 complex. This complex was colorless and needle-like and had a melting point of 58-63°C.

A-liquid formulation 20 parts of the above solvent inclusion complex 2.2
-bis(4'-hydroxyphenyl)propane 201
! Hydroxyethylcellulose 10% aqueous solution 4Qu water
6
0Il Dansangan 1 Same as the B liquid prescription of Example 1. Same as the C liquid prescription of Example 1. A mixture of each of the above formulations was prepared in a magnetic ball mill in the same manner as in Example 1 to prepare a coating liquid. A thermosensitive recording sheet was created.

Example 4 'Scream Nα72.5- (
Bis-2,4-dimethylphenyl)hydroquinone 25
1 part to 50 parts of ethanol, dissolve by heating, and dissolve at room temperature for 12 parts.
Let stand for a while and filter.

A-liquid formulation 15 parts 2.2 of the above solvent inclusion complex
-Bis(4'-hydroxyphenyl)propane 20〃 Hydroxyethyl cellulose 10% aqueous solution 4Qn water
6
o〃Tatsumarutaru 3-(N-methyl-N-cyclohexylamino)-6-
Methyl-7-anirite fluorane 20 parts Hydroxyethylcellulose lO% aqueous solution 20 Water
6 o〃〃 20 parts methyl cellulose 25% aqueous solution 20〃 water
60〃
The formulations of liquids A, B, and C were each dispersed in a magnetic ball mill to a particle size of 3 μm, and 20 parts of liquid A, 10 parts of liquid B, and
30 parts of the solution and 10 parts of a 20% alkaline aqueous solution of isobutylene-maleic anhydride copolymer were mixed, and the resulting coating solution was coated on commercially available high-quality paper with a basis weight of 50 g/% in a dry coating amount of 5 g/r&
It was coated with a wire bar to give the following properties and dried to create a heat-sensitive recording sheet.

Example 5 Preparation of solvent inclusion complex (Table I Na8) 25 parts of 2.5-(his-2,4-dimethylphenyl)hydroquinone was added to 50 parts of monobutanol, dissolved by heating, and 1
Leave to stand for 2 hours and filter.

The above solvent inclusion complex 20 parts Benzyl p-hydroxybenzoate 20 10% aqueous hydroxyl cellulose 40! I water
60〃l 3-(N-diethylamino)-6-methyl-7-anilite fluorane 20 parts Hydroxyethylcellulose 10% aqueous solution 20〃Water
60〃
A mixture of each of the above formulations, which was the same as the C liquid formulation in Example 1, was prepared in a magnetic ball mill in the same manner as in Example 1 to prepare a coating liquid and prepare a heat-sensitive recording sheet.

Example 6 'J5C-I NaIO3,5(
Add 25 parts of bis-4-chlorophenyl)hydroquinone to 50 parts of Impropatool, dissolve with heating, and dissolve at room temperature for 12 parts.
Let stand for a while and filter.

20 parts of the above solvent inclusion complex 2.2
'-bis(4'-hydroxyphenyl)propane
20〃Hydroxy engineered cellulose 10% aqueous solution 401I water
60〃B%
CI+ Same as the B liquid formulation and C liquid formulation in Example 1.

Thermosensitive recording sheets were prepared in the same manner as in Example 1 using each of the above formulations.

In addition, Na 3 (colorless plate-like melting point 60-67°C) in Table-I
), Nα5 (colorless prism melting point 55 to 60°C), and a thermosensitive recording sheet using a solvent inclusion complex of Nα6 and Nα9 as the Δ liquid was also prepared.

Comparative Example 1 A thermosensitive ia record receipt was prepared in the same manner as in Example 1 except that the solvent inclusion complex in the liquid A formulation of Example 1 was removed.

Comparative Example 2 A heat-sensitive recording sheet was prepared in the same manner as in Example 2 except that the solvent inclusion complex in the liquid A formulation of Example 2 was removed.

Each of the heat-sensitive recording sheets obtained in the above manner was
[Printed at high speed with a facsimile machine and measured its color density with a Macbeth densitometer RD-514. The results are as follows.

Claims (1)

[Scope of Claims] (1) In a heat-sensitive recording material that utilizes a color-forming reaction between a colorless or light-colored electron-donating dye and its color developer, the following general formula (I) or the following general formula is used as a color development accelerator: (II)
A heat-sensitive recording material characterized by using a solvent inclusion complex having a compound represented by the following as a host molecule. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (In the formula, X and Y represent hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, or acetyl groups.) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (II) [In the formula, Ar can be a mathematical formula, chemical formula, table, etc. (however, n = an integer from 1 to 3) or ▲ a mathematical formula, chemical formula, table, etc. (however, X is a halogen , m represents an integer of 1 to 2). (2) The heat-sensitive recording material according to claim 1, wherein the clathrating solvent is alcohol. (3) The heat-sensitive recording material according to claim 1 or 2, wherein the solvent inclusion complex is formed and separated in the clathrating solvent.