JP2003089273A - Heat-sensitive recording medium and new developer compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly sensitive recording medium with such advantages that the whiteness of a heat-sensitive paper is high, coloring at the white paper part does not occur in environment-resistant tests, especially simulation tests under high temperature environments such as the inside of an automobile in a hot summer weather or a heating cooking by using an electronic oven, and further, the resistance to oil and a plasticizer is high so that a color-developed image can be stably preserved for a long time. SOLUTION: The heat-sensitive recording medium is composed of a sheet-like base and a heat-sensitive color developing layer which is formed on at least one of the sides of the base and contains a colorless or pale-color dye precursor and a developer which makes the dye precursor develop a color through a chemical reaction with the dye precursor by heat. The developer to be added is at least one kind selected from chemical compounds represented by formulae (I), (II) and (III).

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 which forms a color image by heating.
The present invention relates to a heat-sensitive recording material having high whiteness, no loss of an image once colored, excellent storage stability of recording, and high recording sensitivity.

[0002]

2. Description of the Related Art A thermal recording material is generally composed of a color-forming substance represented by an electron-donating leuco dye and an organic acid represented by an electron-accepting phenolic compound on a support such as paper, synthetic paper and plastic film. A thermosensitive color-developing layer containing a substance (a color-developing substance) as a main component is provided, and they can be reacted with thermal energy to obtain a recorded image. Such thermal recording materials are disclosed in Japanese Examined Patent Publication Nos. 43-4160 and 4
It is disclosed in No. 5-14039 and Japanese Examined Patent Publication No. 48-27736, and is widely put into practical use.

Since the recording device of the thermal recording medium is compact, inexpensive and easy to maintain, the output of an electronic computer, a facsimile, an automatic ticket vending machine, a printer for scientific measuring instruments, a printer for CRT medical measurement, etc. Widely used in. However, in a conventional so-called dye-type thermosensitive recording medium in which a color-forming dye substance, a color-developing substance and a binder as an active ingredient are coated on a support, the color-forming reaction is reversible. It is known that a color image disappears over time. This decolorization is accelerated by exposure to light, high humidity, and high temperature atmosphere, and further, when it is left in water for a long time, oil such as salad oil, and contact with plasticizer significantly progress, and the image becomes unreadable. It will be erased. On the other hand, in the above-mentioned dye-type thermosensitive recording medium, a coloring reaction occurs due to heating, so that when it is kept in a high temperature and high humidity atmosphere, spontaneous coloring (this is referred to as ground coloring) occurs, resulting in contrast. It is also known that the image quality becomes worse and the recorded image becomes difficult to read. In particular, thermal recording type parking tickets and pass tickets left in a car in the summer hot weather, or thermal recording type POS labels heated by a microwave oven with side dishes and lunch boxes in supermarkets and convenience stores are extremely vulnerable. Coloring occurs, and the recorded image becomes unreadable.

A number of techniques for suppressing the above-mentioned decoloring phenomenon are usually used while using a coloring system which usually uses a dye mainly composed of a colorless or light-colored lactone ring compound (for example, Japanese Patent Laid-Open No. Sho 60).
-78782, JP-A-56-146796, JP-A-62-164579, JP-A-62-169681,
JP-A-62-19485) has been disclosed,
Almost no improvement effect is recognized, or some improvement effect is recognized, but in many cases the performance is not satisfactory, for example, it takes a long time for the effect to appear and the effect does not last for a long time. Further, there are cases in which the adverse effects such as background coloration under high temperature and high humidity environment and deterioration of recording sensitivity cannot be avoided by the improved operation, and a practical proposal has been long awaited. As measures completely different from the above, there are JP-A-5-147357 and JP-A-5-3.
No. 2601 discloses a technique in which a sulfonylurea compound is used as a developer instead of a conventional organic acidic compound represented by phenol. This proposal to use a sulfonylurea compound as a color developer is very epoch-making, not only creating a new color-forming functional group, but not only under various environmental conditions such as high temperature and high humidity, Succeeded in completely suppressing even the recorded image decoloring phenomenon of the thermal recording material that was impossible with the contact with oil or plasticizer, and completed a thermal recording material with extremely high storage stability of recorded images. Let

However, with the advent of the above-mentioned sulfonylurea type developer, the storage stability of the recorded image of the thermosensitive recording medium has been dramatically improved, so that it is another drawback of the thermosensitive recording medium under high temperature and high humidity atmosphere. When it is retained, the color develops,
As for the phenomenon that the contrast is deteriorated and the recorded image becomes difficult to read, it has been strongly desired to improve this phenomenon at an early stage. That is, although the proposals of using the sulfonylurea compounds disclosed in JP-A-5-147357 and JP-A-5-32601 for the color developer are effective in improving the storage stability of recorded images, they have been demanded recently. It has not always been possible to suppress the background color formation under more severe environmental conditions such as that described above.

Due to the nature of the heat-sensitive recording material to develop color upon heating, it is inevitable to develop a background color in a high temperature environment, but improvements in color developers and sensitizers (JP-A-63-153183, JP-A-6-1069). It is becoming possible to control the degree to a lower level. However, in recent years, even under harsher environmental conditions than ever before, for example, even when a thermal recording type parking ticket or a pass ticket is left in a car in the summer hot weather, or pasted on a side dish or lunch at a supermarket or convenience store. Even when the heat-sensitive recording type POS label is heated by a microwave oven, the heat-sensitive recording material is required to have a performance capable of reading a recorded image with good contrast without causing background coloration. It can be said that it has reached a turning point. One proposal to meet this demand is to use a compound having a relatively large molecular weight as a developer (Japanese Patent Laid-Open No. 8-333329), but this proposal also has a certain storage stability of recorded images. Thus, although it is effective in suppressing the background color formation under a high temperature and high humidity atmosphere, the recording sensitivity is low and it cannot be practically used. As described above, there has not been proposed a thermosensitive recording medium which has both the storage stability of a recorded image and the ability to suppress the background color formation under more severe environmental conditions, and has practically sufficient basic performance.

On the other hand, the present invention is applied to a heat-sensitive recording medium capable of repeating recording and erasing of an image by controlling heating temperature and cooling rate, that is, a so-called heat-sensitive recording rewrite medium (sometimes called a reversible heat-sensitive recording medium). It has been disclosed that a compound having a certain structural similarity with the compound group (1) is used as a developer (JP-A-7-257033). However, the heat-sensitive recording type rewritable medium disclosed in JP-A-7-257033 has a long-chain aliphatic group because it aims to erase the recorded image more quickly by applying heat energy to the recorded image again. It is essential to include a compound as a color developer, and the present invention made with one of the main purposes that the recorded image does not disappear even if high heat is applied once recording is carried out. The design and selection guidelines for the compounds used in the colorants are also completely different.

[0008]

The present invention solves these problems, and the thermal paper has high whiteness, and in the environment resistance test, it is assumed that the paper is cooked in a car especially in the summer hot weather or in a microwave oven. Provides a high-sensitivity thermosensitive recording medium that suppresses the color development of the blank area even under such high temperature environment, does not erase the recorded image, and has excellent long-term storage stability of the colored image such as oil resistance and plasticizer resistance. Is what you are trying to do. INDUSTRIAL APPLICABILITY The present invention can be used not only as a pass ticket for expressways and toll roads, as a thermal recording type ticket for automatic ticket vending machines, as a parking ticket, as an admission ticket, but also as a coupon ticket or a commuter ticket that requires preservation. P, affixed to the packaging surface of foods packaged with a polyvinyl chloride film that is inevitable for use in contact with plasticizers and fats and oils.
Provided is a thermal recording material suitable as a label for an OS barcode system.

[0009]

The present invention includes the following aspects. [1] A thermosensitive color development comprising a sheet-like substrate, a colorless or light-colored dye precursor which is formed on at least one surface of the substrate, and a color developer which reacts with the dye precursor under heating to develop the color. A thermosensitive recording material having a layer, which contains at least one compound selected from compounds represented by the following general formulas (I), (II) and (III) as the color developer. body.

[Chemical 12] (In the formula, R ₁ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and X ₁ represents an oxygen atom. Alternatively, a sulfur atom, Y ₁ represents a divalent group containing two or more carbon atoms, and Z ₁ represents a monovalent group having at least one hetero atom, and Z ₁ is a sulfonylurea (—SO ₂ NHCON
H-) group is excluded. The number of —COOY ₁ Z ₁ groups may be 1 or 2 or more on the benzene ring. When there are two or more, a plurality of —COOY ₁ Z ₁ groups may be the same or different. However, the number of —COOY ₁ Z ₁ groups is preferably one. )

[Chemical 13] (In the formula, R ₂ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and R ₃ is a monovalent group. And an X ₂ represents an oxygen atom or a sulfur atom, and one or more —SO ₂ OR ₃ groups may be present on the benzene ring. -SO ₂ O
The R ₃ groups may be the same or different. However -SO ₂ O
One R ₃ group is preferred. )

[Chemical 14] (In the formula, R ₄ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and R ₅ and R ₆ represent independently of one another a monovalent organic residue, also, X ₃ represents an oxygen atom or a sulfur atom.-PO ₃ (R ₅₎
There may be one or two or more (R ₆ ) groups on the benzene ring. If two or more, a plurality of _{-PO 3 (R 5) (R} 6)
The groups may be the same or different. However-PO
_{One 3} (R ₅ ) (R ₆ ) group is preferable. )

[2] The compound represented by the general formula (I) is
The heat-sensitive recording material according to [1], which is a compound represented by the following general formula (IV).

[Chemical 15] (In the formula, R₇Is an unsubstituted aromatic hydrocarbon group, or
From a rualkyl group, an alkoxyl group, or a halogen atom
Aromatic hydrocarbons substituted by at least one selected member
Represents a base group, and Y₂Is divalent containing two or more carbon atoms
Represents a group of₂Is an alkyl group, an aryl group,
Kuha is at least one member selected from the aralkyl group.
Substituted sulfonyl group, or alkyl group, aryl
Group or at least one member selected from aralkyl groups
Represents an imide group substituted by. -COOY₂Z₂Basis
May be 1 or 2 or more on the benzene ring. Two
In the above case, a plurality of -COOY₂Z₂The groups are the same or different
May be. However, -COOY ₂Z₂1 group is preferred
Yes. ) [3] The compound represented by the general formula (I) has the following general formula:
Selected from the group of compounds represented by (V), (VI) and (VII)
The heat-sensitive material according to [1], which is at least one kind of compound
Record body.

[Chemical 16] (In the formula, R ₈ is an unsubstituted aromatic hydrocarbon group, or a methyl group, a methoxy group, or an aromatic hydrocarbon group substituted by at least one member selected from chlorine atoms, R 8
₉ represents a member selected from a hydrogen atom, a chlorine atom, a nitro group, an alkyl group, an alkoxyl group, an aryl group, an aryloxy group, an aralkyl group and an aralkyloxy group,
Two or more may be independently substituted on the benzene ring, and Y ₃ represents a divalent group containing 2 or more carbon atoms. The number of ester groups having Y ₃ may be 1 or 2 or more on the benzene ring. When there are two or more, the plurality of ester groups having Y ₃ may be the same or different. However, one ester group having Y ₃ is preferable. )

[Chemical 17] (In the formula, R ₁₀ represents an unsubstituted aromatic hydrocarbon group, or an aromatic hydrocarbon group substituted by at least one member selected from a methyl group, a methoxy group, or a chlorine atom,
R ₁₁ and R ₁₂ may independently form a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, or, together, form a cyclopentane ring, a cyclohexane ring, a dicyclopentane ring, or a benzene ring. , Y ₄ represents a divalent group containing two or more carbon atoms. The number of ester groups having Y ₄ may be 1 or 2 or more on the benzene ring. When there are two or more, the plurality of ester groups having Y ₄ may be the same or different. However, one ester group having Y ₄ is preferable. )

[Chemical 18] (In the formula, R ₁₃ represents an unsubstituted aromatic hydrocarbon group, or a methyl group, a methoxy group, or an aromatic hydrocarbon group substituted by at least one member selected from chlorine atoms;
₁₄ represents a member selected from an alkyl group, an aryl group and an aralkyl group, and Y ₅ represents a divalent group containing 2 or more carbon atoms. The number of ester groups having Y ₅ may be 1 or 2 or more on the benzene ring. If two or more,
The plural ester groups having Y ₅ may be the same or different. However, one ester group having Y ₅ is preferable)

[4] The following chemical formula (VIII):

[Chemical 19] 3-p-toluenesulfonylpropyl represented by
4-p-toluenesulfonylaminocarbonylaminobenzoate, the following chemical formula (IX):

[Chemical 20] 4- [4- (4-iso-propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate represented by the following chemical formula (X):

[Chemical 21] N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide represented by: and the following chemical formula (XI):

[Chemical formula 22] N-phenyl-N′-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea represented by

[5] Compounds (VIII) and (I) described in [4]
A developer containing at least one selected from X), (X) and (XI). [6] General formulas (I), (II) and (II) described in [1]
A developer containing at least one compound selected from the compounds represented by I). [7] A thermosensitive recording medium containing the color developer according to [5].

In the present specification, the imide group means an imino group (C-NH-C) and an acid imide (OC-NH-C).
CO), including the case where the acid imide is a compound in which two hydrogen atoms of ammonia are substituted with an acyl group,
It may be a cyclic imide derived from the acyl group of a basic acid. Acid imides are preferred in the present invention. Chemical formula (VII
The compounds represented by I), (IX), (X) and (XI) are novel compounds.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The compounds represented by the general formulas (I), (II) and (III) used in the present invention act as a color developer. That is, the compounds represented by the general formulas (I), (II) and (III) do not have an acidic functional group such as a phenolic hydroxyl group or a carboxyl group, but the sulfonylurea group present in the molecule is basic. It has a strong color developing ability for leuco dyes. Further, it is considered that the excellent characteristics that the color development of the white paper portion is suppressed and the recorded image is not erased especially in a high temperature environment are comprehensively exhibited by the overall characteristics of the compound of the present invention. .

Examples of the R ₁ group in the above general formula (I) include aromatic hydrocarbon groups having 6 to 20 carbon atoms and 1 to 1 carbon atoms.
15 aliphatic hydrocarbon groups are preferable, and specifically, phenyl group, 2-naphthyl group, p-tolyl group, o-tolyl group, m-tolyl group, p-chlorophenyl group, p-methoxyphenyl group, benzyl group. Group, cyclohexyl group, methyl group, ethyl group and the like.

The Y ₁ group in the above general formula (I) is not particularly limited as long as it is a divalent group having 2 or more carbon atoms, but the number of carbon atoms selected from the following group is about 1. A member composed of up to about 30 pieces is desirable. (A) a divalent group formed by removing two hydrogens from a chain or cyclic aliphatic hydrocarbon, specifically, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group,
Hexamethylene group, nonamethylene group, or 1-methyl-1,3-trimethylene group having a substituent on the side chain, 2,
Examples thereof include a 3-dimethyl-1,4-tetramethylene group, a 1,4-cyclohexyl group, and a 1,4-cyclohexanedimethylene group.

(B) a divalent group formed by removing two hydrogen atoms from a compound in which a part of a chain or cyclic aliphatic hydrocarbon is replaced by a hetero atom, or a chain or cyclic aliphatic hydrocarbon A part is a divalent group formed by removing two hydrogen atoms from a compound in which an aromatic compound and a hetero atom are substituted. Specifically, 1,5- (3-oxapentylene) group, 1,5- (3-thiopentylene)
Group, 2,5- (1-oxacyclohexylene) group, 1-
Oxacyclohexane-2,5-dimethylene group, 1,8
-(3,6-dioxaoctylene) group, 1,12-
(3,6,9-trioxadodecylene), 2-phenyleneoxyethylene group, 3-phenyleneoxypropylene group, 4-phenyleneoxybutyl group, 1,3-bis-phenyleneoxypropylene group and the like. it can.

(C) From an alkyl group or an aromatic compound partially substituted with a hetero atom, an alkyl group or two hydrogen atoms from an alkyl group partially substituted with a hetero atom. A divalent group produced by removal, specifically, α, α '-(p-xylylene) group, α, α'-(m-xylylene) group, β, β'-
(1,4-di (dimethylene) benzene) group, γ, γ'-
Examples thereof include a (1,4-di (trimethylene) benzene) group and a divalent group formed by removing β, β ′ hydrogen of p-hydroquinone diethyl ether.

Further, with respect to the Z ₁ group in the above general formula (I), for example, a hydroxyl group, a carboxylic acid group, a sulfonic acid group, a nitro group, a cyano group, a formyl group, a formyl ester group, a formylamide group, a halogen atom, etc. In addition, an amino group substituted with an alkyl group, an aryl group or an aralkyl group, an alkoxyl group, a carbonyl group, a (thio) carboxyl group, an oxycarbonyl group, a (thio) amide group, an aminocarbonyl group, a (thio) urea Group, sulfonyl group, sulfonyloxy group, oxysulfonyl group,
Substituents such as a sulfonylamide group, an aminosulfonyl group, and a phosphoric acid group can be given. In addition, the above Y ₁ group,
A cyclic imide group characterized by being bonded to a nitrogen atom can also be used as the Z ₁ group.

Specific examples of the color developer according to the present invention represented by the general formula (I) include 2-p-toluenesulfonylethyl 4-p-toluenesulfonylaminocarbonylaminobenzoate and 2-p-toluenesulfonyl. Ethyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 3-p-toluenesulfonylpropyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 4- p-toluenesulfonylbutyl
4-p-toluenesulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylbutyl 3-
p-toluenesulfonylaminocarbonylaminobenzoate, 5-p-toluenesulfonyl-3-oxapentyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 5-p-toluenesulfonyl-3-
Oxapentyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 8-p-toluenesulfonyl-3,6-dioxaoctyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 8-p
-Toluenesulfonyl-3,6-dioxaoctyl 3
-P-toluenesulfonylaminocarbonylaminobenzoate, 12-p-toluenesulfonyl-3,6,9
-Trioxadodecyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 12-p-toluenesulfonyl-3,6,9-trioxadodecyl 3-
p-toluenesulfonylaminocarbonylaminobenzoate, 9-p-toluenesulfonylnonyl 4-p-
Toluenesulfonylaminocarbonylaminobenzoate, 9-p-toluenesulfonylnonyl 3-p-toluenesulfonylaminocarbonylaminobenzoate,
4-p-toluenesulfonylmethylcyclohexylmethyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylmethylcyclohexylmethyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylmethylphenylmethyl 4 -P-toluenesulfonylaminocarbonylaminobenzoate, 4-p-
Toluenesulfonylmethylphenylmethyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 3- [4- (4-iso-propoxyphenylsulfonyl) phenoxy)] propyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 3-
[4- (4-iso-propoxyphenylsulfonyl)
Phenoxy)] propyl 3-p-toluenesulfonylaminocarbonylaminobenzoate, 4- [4- (4
-Iso-propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 4- [4- (4-iso-
Propoxyphenylsulfonyl) phenoxy)] butyl 3-p-toluenesulfonylaminocarbonylaminobenzoate,

3-p-toluenesulfonylpropyl methylsulfonylaminocarbonylaminobenzoate,
3-p-toluenesulfonylpropyl ethylsulfonylaminocarbonylaminobenzoate, 3-p-toluenesulfonylpropyl cyclohexylsulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylbutyl methylsulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylbutyl ethyl Sulfonylaminocarbonylaminobenzoate, 4-p-toluenesulfonylbutyl cyclohexylsulfonylaminocarbonylaminobenzoate,
5-p-toluenesulfonyl-3-oxapentyl methylsulfonylaminocarbonylaminobenzoate,
5-p-toluenesulfonyl-3-oxapentyl ethylsulfonylaminocarbonylaminobenzoate,
5-p-toluenesulfonyl-3-oxapentyl cyclohexylsulfonylaminocarbonylaminobenzoate, 8-p-toluenesulfonyl-3,6-dioxaoctyl methylsulfonylaminocarbonylaminobenzoate, 8-p-toluenesulfonyl-3,6-
Dioxaoctyl ethylsulfonylaminocarbonylaminobenzoate, 8-p-toluenesulfonyl-
3,6-Dioxaoctyl cyclohexylsulfonylaminocarbonylaminobenzoate, 9-p-toluenesulfonylnonyl methylsulfonylaminocarbonylaminobenzoate, 9-p-toluenesulfonylnonyl ethylsulfonylaminocarbonylaminobenzoate, 9-p-toluenesulfonylnonyl cyclohexyl Sulfonylaminocarbonylaminobenzoate,

N-2- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylphthalimide, N-2- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylphthalimide, N-3- (3- p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide, N-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide, N-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) Butylphthalimide,
N-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butylphthalimide, N-
2- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylsuccinimide, N-2
-(4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylsuccinimide, N-3-
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylsuccinimide, N-3-
(4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylsuccinimide, N-4-
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butylsuccinimide, N-4-
(4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butylsuccinimide, N-2-
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylhexahydrophthalimide,
N-2- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethylhexahydrophthalimide, N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylhexahydrophthalimide, N-3- (4 -P-toluenesulfonylaminocarbonylaminobenzoyloxy) propylhexahydrophthalimide, N-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butylhexahydrophthalimide, N-4- (4-
p-toluenesulfonylaminocarbonylaminobenzoyloxy) butylhexahydrophthalimide,

N-methyl-N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-methyl-N'-3-
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-methyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-methyl -N'-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-ethyl-N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio ) Urea, N-ethyl-N'-3
-(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-ethyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N- Ethyl-N'-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-propyl-N'-3- (4-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-propyl-
N'-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-propyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) Urea, N-propyl-N'-4- (3-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-isopropyl-
N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-isopropyl-N'-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy)
Propyl (thio) urea,

N-isopropyl-N'-4- (4-p-
Toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-isopropyl-
N′-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea,
N-butyl-N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-butyl-N'-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) Propyl (thio) urea, N-butyl-N'-4
-(4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-butyl-N'-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N- tert-butyl-N′-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-tert-butyl-
N'-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-tert-butyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl ( Thio) urea, N-tert-butyl-
N′-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea,
N-hexyl-N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-hexyl-N'-3- (3-p-
Toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-hexyl-N ′
-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-
Hexyl-N'-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-cyclohexyl-N'-3- (4-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea,

N-cyclohexyl-N'-3- (3-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-cyclohexyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-cyclohexyl-N'- 4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, N-phenyl-N'-2-
(4-p-Toluenesulfonylaminocarbonylaminobenzoyloxy) ethyl (thio) urea, N-phenyl-N'-2- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ethyl (thio) urea, N-phenyl -N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-phenyl-N'-3- (3-
p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N-phenyl-
N′-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea,
N-phenyl-N'-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, Np-tolyl-N'-3- (4-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, Np-tolyl-
N'-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, Np-tolyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl ( Thio) urea, Np-tolyl-N'-4- (3
-P-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, Np-methoxyphenyl-N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, N- p-methoxyphenyl-N'-3
-(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propyl (thio) urea, Np
-Methoxyphenyl-N'-4- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, Np-methoxyphenyl-N '
-4- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) butyl (thio) urea, 1,2
-Di-3-toluenesulfonylpropyl 4- (N-p
-Toluenesulfonylaminocarbonylamino) phthalate, 1,3-di-3-toluenesulfonylpropyl
Examples thereof include 5- (Np-toluenesulfonylaminocarbonylamino) isophthalate. still,
(Thio) urea means urea or thiourea. The compound of the general formula (I) is represented by the general formula (IV)
A compound represented by the formula (V)
The compounds represented by (VI) and (VII) are preferred.

Further, the R ₂ group in the above general formula (II) is preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms and an aliphatic hydrocarbon group having 1 to 15 carbon atoms, specifically,
Examples thereof include phenyl group, 2-naphthyl group, p-tolyl group, o-tolyl group, m-tolyl group, p-chlorophenyl group, p-methoxyphenyl group, benzyl group, cyclohexyl group, methyl group and ethyl group. The R ₃ group is not particularly limited as long as it is a monovalent organic residue, but is an alkyl group having 8 or less carbon atoms, an aralkyl group substituted with an alkyl group having 8 or less carbon atoms, or Aryl groups are preferred.

Specific compounds of the developer of the present invention represented by the general formula (II) include methyl 4-p-toluenesulfonylaminocarbonylaminobenzene sulfonate and ethyl 4-p-toluenesulfonylaminocarbonylamino. Benzene sulfonate, propyl 4-
p-toluenesulfonylaminocarbonylaminobenzenesulfonate, isopropyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate,
Butyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, isobutyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, tert-butyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, cyclohexyl 4-p-toluenesulfonylaminocarbonyl Aminobenzene sulfonate, phenyl 4-p
-Toluenesulfonylaminocarbonylaminobenzenesulfonate, o-tolyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, p-
Tolyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, m-tolyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, methyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, ethyl 3-
p-toluenesulfonylaminocarbonylaminobenzenesulfonate, propyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, isopropyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, butyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, isobutyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, tert-
Butyl 3-p-toluenesulfonylaminocarbonylaminobenzene sulfonate, cyclohexyl 3-p
-Toluenesulfonylaminocarbonylaminobenzenesulfonate, phenyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, o-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate, p-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzene Sulfonate, m-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzenesulfonate,

Methyl cyclohexylsulfonylaminocarbonylaminobenzenesulfonate, ethyl cyclohexylsulfonylaminocarbonylaminobenzenesulfonate, propyl cyclohexylsulfonylaminocarbonylaminobenzenesulfonate, isopropyl cyclohexylsulfonylaminocarbonylaminobenzenesulfonate, butyl cyclohexylsulfonylaminocarbonylaminobenzenesulfonate,
Isobutyl methylsulfonylaminocarbonylaminobenzene sulfonate, tert-butyl ethylsulfonylaminocarbonylaminobenzene sulfonate,
Cyclohexylmethylsulfonylaminocarbonylaminobenzenesulfonate, phenylethylsulfonylaminocarbonylaminobenzenesulfonate, o-
Tolyl cyclohexylsulfonylaminocarbonylaminobenzene sulfonate, p-tolyl methylsulfonylaminocarbonylaminobenzene sulfonate, m
-Tolyl ethylsulfonylaminocarbonylaminobenzene sulfonate, dimethyl 4-p-toluenesulfonylaminocarbonylaminobenzene-1,2-disulfonate, dimethyl 5-p-toluenesulfonylaminocarbonylaminobenzene-1,3-disulfonate and the like. be able to.

Further, the R ₄ group in the above general formula (III) is preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms and an aliphatic hydrocarbon group having 1 to 15 carbon atoms, and specifically, phenyl Group, 2-naphthyl group, p-tolyl group, o-
Tolyl group, m-tolyl group, p-chlorophenyl group, p-
Methoxyphenyl group, benzyl group, cyclohexyl group,
Examples thereof include a methyl group and an ethyl group. R ₅ and R ₆ groups are not particularly limited as long as they are monovalent organic residues, but are alkyl groups having 8 or less carbon atoms and 8 carbon atoms. Aralkyl or aryl groups substituted with up to 4 alkyl groups are preferred.

A specific compound of the color developing agent of the present invention represented by the general formula (III) is dimethyl 4-p-
Toluenesulfonylaminocarbonylaminobenzenephosphonate, diethyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dipropyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, diisopropyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dibutyl 4- p-toluenesulfonylaminocarbonylaminobenzenephosphonate, diisobutyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, di-tert-butyl 4-
p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dicyclohexyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, diphenyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, di-o-tolyl 4-p-toluenesulfonylaminocarbonylamino Benzenephosphonate, di-p-tolyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, di-m-tolyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dimethyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, Diethyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dipropyl 3-p-to En sulfonylaminocarbonyl-aminobenzene phosphonate, diisopropyl 3-p-toluenesulfonyl-aminocarbonyl-aminobenzene phosphonate, dibutyl 3-p-toluenesulfonyl-aminocarbonyl-aminobenzene phosphonate, diisobutyl 3-p-toluenesulfonyl-aminocarbonyl-aminobenzene phosphonate, di -tert
-Butyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, dicyclohexyl 3
-P-toluenesulfonylaminocarbonylaminobenzenephosphonate, diphenyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate,
Di-o-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, di-p-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate, di-m-tolyl 3-p-toluenesulfonylaminocarbonylaminobenzenephosphonate ,

Dimethyl cyclohexylsulfonylaminocarbonylaminobenzenephosphonate, diethyl
Cyclohexylsulfonylaminocarbonylaminobenzenephosphonate, dipropylcyclohexylsulfonylaminocarbonylaminobenzenephosphonate, diisopropylcyclohexylsulfonylaminocarbonylaminobenzenephosphonate, dibutylcyclohexylsulfonylaminocarbonylaminobenzenephosphonate, diisobutylmethylsulfonylaminocarbonylaminobenzenephosphonate, di-tert-butylethyl Sulfonylaminocarbonylaminobenzenephosphonate, dicyclohexylmethylsulfonylaminocarbonylaminobenzenephosphonate, diphenylethylsulfonylaminocarbonylaminobenzenephosphonate, di-o-tolylmethylsulfonylaminocarbonylaminobenzene Phosphonate, di-p-tolyl ethylsulfonylaminocarbonylaminobenzenephosphonate, di-m-tolyl cyclohexylsulfonylaminocarbonylaminobenzenephosphonate,
Examples thereof include tetramethyl 4-p-toluenesulfonylaminocarbonylaminobenzene-1,2-diphosphonate and tetramethyl 5-p-toluenesulfonylaminocarbonylaminobenzene-1,3-diphosphonate. These compounds may be used alone or in a mixture of two or more thereof. The compounds represented by the above general formulas (I), (II) and (III) can be synthesized according to the method described in Examples.

Among these compounds, 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate represented by the above chemical formula (VIII) and 4- [4 represented by the above chemical formula (IX).
-(4-iso-propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) represented by the above chemical formula (X). Propylphthalimide, and N-phenyl-represented by the above chemical formula (XI)
N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea is a developer that is particularly excellent in plasticizer resistance and heat resistance.

Examples of the leuco dye used as the dye precursor in the present invention include triphenylmethane type, fluorane type and diphenylmethane type compounds, which can be selected from conventionally known ones. For example, 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide, crystal violet lactone, 3- (N-ethyl-N-).
Isopentylamino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-
(O, p-dimethylanilino) fluorane, 3- (N-
Ethyl-N-p-toluidino) -6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 3-dibutylamino-6-methyl-
7-anilinofluorane, 3- (N, N-dipentylamino) -6-methyl-7-anilinofluorane 3- (N
-Cyclohexyl-N-methylamino) -6-methyl-
7-anilinofluorane, 3-diethylamino-7-
(O-chloroanilino) fluorane, 3-diethylamino-7- (o-chloroanilino) fluorane, 3-dibutylamino-7- (m-trifluoromethylanilino)
Fluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-6-methylfluorane, and 3-cyclohexylamino-6-chlorofluorane, 3- (N-ethyl-N-hexylamino)
One or more selected from -6-methyl-7- (p-chloroanilino) fluorane and the like can be used.

In the present invention, a conventionally known color developer comprising a phenol, a color developer having one or two sulfonylurea groups in one molecule, or an organic acid within a range that does not inhibit a desired effect. The agent is represented by the general formula (I) of the present invention,
It can be used in combination with a compound selected from (II) and (III). As these conventional color developers, for example,
2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,4-bis (1-methyl-1- (4′-) Hydroxyphenyl) ethyl) benzene, 1,3-bis (1-methyl-1- (4'-hydroxyphenyl) ethyl) benzene, dihydroxydiphenyl ether (JP-A-1-180382), benzyl p-hydroxybenzoate (JP-A-SHO) 52-140483
No.), bisphenol S, 4-hydroxy-4′-isopropyloxydiphenyl sulfone (JP-A-60-13).
852), 1,1-di (4-hydroxyphenyl) cyclohexane, 1,7-di (4-hydroxyphenylthio) -3,5-dioxaheptane (JP-A-59-526).
94), 3,3'-diallyl-4,4'-dihydroxydiphenyl sulfone (JP-A-60-208286).
No.), 2,4-bis (phenylsulfonyl) phenol (JP-A-8-269000).

Further, as a color developing agent other than phenol, N- (p is disclosed in JP-A-5-32601.
-Toluenesulfonyl) -N'-phenylurea, N-
(P-Toluenesulfonyl) -N '-(p-methoxyphenyl) urea, N- (p-toluenesulfonyl) -N'
-(O-tolyl) urea, N- (p-toluenesulfonyl) -N '-(m-tolyl) urea, N- (p-toluenesulfonyl) -N'-(p-tolyl) urea, N- (p −
Toluenesulfonyl) -N '-(o-chlorophenyl)
Examples thereof include compounds having one sulfonylurea group in one molecule such as urea, N- (benzenesulfonyl) -N'-phenylurea and N- (p-chlorobenzenesulfonyl) -N'-phenylurea. Further, 4,4-bis (p-toluenesulfonylaminocarbonylamino) diphenylmethane, 1,8- (3,6-
Dioxaoctylene) bis (4- (p-toluenesulfonylaminocarbonylamino) benzoate and other compounds having two or more sulfonylurea groups in one molecule, and a developer having a phenol structure and a sulfone group in one molecule As described in JP-A-8-269000,
In addition to 4-bis (phenylsulfonyl) phenol,
Two p-hydroxydiphenyl sulfone structures in one molecule disclosed in JP-A-8-333329,
Examples thereof include a developer which is linked with ethylene or ethylene oxide or a polyethylene oxide chain.

Further, in the present invention, a conventionally known heat-fusible substance (sensitizer) may be used in combination within a range that does not impair the desired effect. Typical examples of these are 1-
Hydroxy-2-naphthoic acid phenyl ester (JP-A-57-191089), p-benzylbiphenyl (JP-A-60-82382), benzylnaphthyl ether (JP-A-58-87094), dibenzyl terephthalate (special JP-A-58-98285), benzyl p-benzyloxybenzoate (JP-A-57-201691),
Diphenyl carbonate, ditolyl carbonate (JP-A-58-1364)
89), m-terphenyl (JP-A-57-89994).
No.), 1,2-bis (m-tolyloxy) ethane (JP-A-60-56588), 1,5-bis (p-methoxyphenoxy) -3-oxapentane (JP-A-62-18).
1183), oxalic acid diesters (JP-A-64-1)
583), 1,4-bis (p-tolyloxy) benzene (JP-A-2-153787), and the like.

The heat-sensitive color forming layer of the heat-sensitive recording material of the present invention may further contain waxes, and preferably contains organic or inorganic pigments. The heat-sensitive color forming layer further contains a binder for fixing these components to the support.

The content of the above leuco dye in the thermosensitive color forming layer is generally 5% of the dry mass of the thermosensitive color forming layer.
It is preferably about 20% by mass. Generally, the content of the color developer of the present invention is preferably 5 to 50% by mass based on the thermosensitive color developing layer. Further, when a sensitizer is contained, it is 5
The amount is preferably 50% by mass to 50% by mass, more preferably 10% by mass to 40% by mass.

When the heat-sensitive color-developing layer contains a conventionally known phenol-based or organic acid-based developer, its content is 5
It is preferably ˜40% by mass. When waxes and white pigments are contained in the thermosensitive coloring layer, the content thereof is preferably 2% by mass to 20% by mass and 2% by mass to 50% by mass, and the content of the binder is generally 5% by mass. Is about 20% by mass.

Examples of the above-mentioned organic or inorganic pigments include calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, calcined clay, talc, and surface-treated calcium carbonate. Inorganic fine powder such as silica and silica, urea-formalin resin, styrene / methacrylic acid copolymer,
And organic fine powder such as polystyrene resin. Examples of waxes include paraffin, amide wax, bisimide wax,
Known ones such as metal salts of higher fatty acids can be used.

Regarding the binder, polyvinyl alcohols having various molecular weights, starch and its derivatives, cellulose derivatives such as methoxycellulose, carboxymethylcellulose, methylcellulose and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylic acid amide / acrylic acid ester Polymer, acrylic acid amide / acrylic acid ester / methacrylic acid terpolymer, styrene / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, and water-soluble polymer material such as casein, and
Polyvinyl acetate, polyurethane, styrene / butadiene copolymer, polyacrylic acid, polyacrylic ester,
Each latex such as vinyl chloride / vinyl acetate copolymer, polybutyl methacrylate, ethylene / vinyl acetate copolymer, and styrene / butadiene / acrylic copolymer can be used.

The sheet-like substrate used in the thermosensitive recording medium of the present invention is paper (including acidic papermaking paper and neutral papermaking paper), coated paper having a surface coated with a pigment, latex, etc., laminated paper, polyolefin resin. You can choose from synthetic paper made from, plastic film, etc. At least one surface of such a sheet-like substrate is coated with a coating solution containing a mixture of the above-mentioned required components and dried to produce a thermosensitive recording medium. The coating amount is 1 to 1 when the coating liquid layer is dried.
Preferably ^{5g / m 2, 2~10g / m} 2 is particularly preferred.

In the thermosensitive recording medium of the present invention, a coating layer such as a protective layer or a printing layer can be further formed on the thermosensitive coloring layer. An undercoat layer containing a pigment (preferably an oil-absorbing pigment) and an adhesive can be provided between the support and the thermosensitive coloring layer.

The present invention not only has high recording sensitivity and whiteness, but also has good long-term storage stability of recording, that is, environmental resistance such as heat resistance and humidity resistance of recorded images, and further oil resistance and resistance. It has excellent plasticizer properties and does not cause ground coloration even under high temperature and high humidity atmosphere, especially in automobiles under hot summer weather and in the harsh environment equivalent to heating and cooking by microwave oven, and erases recorded images. Non-image recording paper, cash dispenser paper, boarding ticket, pass ticket, parking ticket, admission ticket, commuter pass, and labels such as POS labels, and heat sensitive materials that are advantageously used for prepaid cards and other cards. Provide a recording body.

[0045]

EXAMPLES The present invention will be specifically described with reference to the following examples. Unless otherwise specified, “parts” and “%” represent “parts by mass” and “mass%”, respectively.

<Synthesis Example 1> Synthesis of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (chemical formula (VIII)): (1) Intermediate material 3-p-toluenesulfonylpropyl 4
-Aminobenzoate synthesis In a three-necked flask equipped with a thermometer, a reflux tube and a dropping funnel, 6.0 g of sodium toluenesulfinate and 80
1 ml of 3-bromo-1-chloropropane was added at room temperature while adding ml of ethanol and stirring with a magnetic stirrer. The reaction suspension was stirred at room temperature, heated under reflux at 100 ° C. for 5 hours, cooled to room temperature, added with 800 ml of hexane, and stirred vigorously to precipitate a white solid. The white solid was filtered, washed with water, and then purified by a recrystallization method to obtain 5.9 g of white crystals. Then 3.0 g of p-aminobenzoic acid and 1
20 ml of N, N-dimethylacetamide was added and 1.8 g of potassium carbonate (anhydrous) was added to the solution. While stirring this mixture with a magnetic stirrer, 5.0 g of the white crystals obtained by the above operation was added at room temperature. The reaction suspension was stirred at room temperature, heated under reflux at 130 ° C. for 5 hours, cooled to room temperature, added with 800 ml of water, and stirred vigorously to precipitate a white solid. This white solid was filtered and purified by a recrystallization method to obtain 6.2 g.
Of white crystals were obtained. The analytical values of this white crystal are as follows.

Melting point; 75 ° C. Results of NMR measurement (in CDCL ₃ ) (numbers are ppm) δ 1.92 (m, 2H), 2.40 (s, 3H), 3.
40 (t, 2H), 4.14 (t, 2H), 6.53
(D, 2H), 7.45 (d, 2H), 7.59 (d,
2H), 7.83 (d, 2H) In addition to this, the peak that is thought to be due to NH is δ5.97.
It appeared near (s, 2H). Results of IR measurement (KBr tablet method) (characteristic absorption only) 1693 cm ^-1 (derived from carbonyl group of ester group) 1343, 1157 cm ^-1 (derived from sulfonyl group) 3117 cm ^-1 (derived from amino group)

(2) Synthesis of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (formula (VIII)) In a three-necked flask equipped with a dropping funnel, a thermometer and a reflux condenser, 6.2 g of Add 3-p-toluenesulfonylpropyl 4-aminobenzoate and add 200 ml to it.
Of toluene was added and stirred to dissolve 3-p-toluenesulfonylpropyl 4-aminobenzoate. While stirring this mixed solution with a magnetic stirrer, 4.2 g of p-toluenesulfonyl isocyanate was added dropwise at room temperature from a dropping funnel. Continued stirring of the reaction mixture caused a large amount of white solid to precipitate. The reaction mixture was heated at 70 ° C. for 2 hours, cooled and filtered to give 1
0.2 g of white crystals were obtained. The analytical values of this white crystal are as follows.

Melting point; 158 ° C. Results of NMR measurement (in heavy DMSO) (numbers are ppm) δ 1.92 (m, 2H), 2.36 (s, 3H), 2.
39 (s, 3H), 3.42 (t, 2H), 4.22
(T, 2H), 7.35 (d, 2H), 7.42 (d,
2H), 7.45 (d, 2H), 7.69 (d, 2)
H), 7.78 (d, 2H), 7.86 (d, 2H) In addition to this, peaks which are considered to be derived from NH are δ 3.33.
It appeared near (s, 1H) and 9.23 (s, 1H). Results of IR measurement (KBr tablet method) (only characteristic absorption) 1723 cm ^-1 (derived from carbonyl group of urea group) 1689 cm ^-1 (derived from carbonyl group of ester group) 1343, 1157 cm ^-1 (derived from sulfonyl group)

<Synthesis Example 2> 4- [4- (4-iso-
Propoxyphenylsulfonyl) phenoxy] butyl
4-p-toluenesulfonylaminocarbonylaminobenzoate (chemical formula (IX)): 4- [4- (4-iso-propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate 9.1 g (white Crystal) was synthesized in the same manner as in Synthesis Example 1. However, in synthesizing 4- [4- (4-iso-propoxyphenylsulfonyl) phenoxy] butyl 4-aminobenzoate (6.8 g) as the starting material, 3-bromo-1-chloropropane was used as the starting material instead of 3-bromo-1-chloropropane. 4-Bromo-4- (4-iso-propoxyphenylsulfonyl) phenoxybutyl (8.0 g) was used, and p-aminobenzoic acid (2.6 g) was used as an esterification material. The analytical values of this white crystal are as follows.

Melting point: 133 ° C. Results of NMR measurement (in heavy DMSO) (numbers are ppm) δ1.26 (d, 6H), 1.82 (m, 4H), 2.
41 (s, 3H), 4.07 (m, 2H), 4.19
(M, 2H), 4.26 (m, 1H), 7.35 (d,
2H), 7.42 (d, 2H), 7.15 (m, 4)
H), 7.43 (m, 4H), 7.84 (m, 8H) In addition to this, peaks which are thought to be due to NH are δ 3.33.
It appeared near (s, 1H) and 9.23 (s, 1H). Results of IR measurement (KBr tablet method) (only characteristic absorption) 1721 cm ^-1 (derived from carbonyl group of urea group) 1688 cm ^-1 (derived from carbonyl group of ester group) 1345, 1156 cm ^-1 (derived from sulfonyl group)

<Synthesis Example 3> N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide (chemical formula (X)): N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) ) Propylphthalimide 1
0.2 g (white crystal) was synthesized in the same manner as in Synthesis Example 1. However, N-3-bromopropylphthalimide (13.7 g) instead of 3-bromo-1-chloropropane and m-aminobenzoic acid (7.0 g) instead of p-aminobenzoic acid were used as esterification materials. I was there. The analytical values of this white crystal are as follows.

Melting point: 190 ° C. NMR measurement result (in heavy DMSO) (numerical value is ppm) δ2.06 (m, 2H), 2.38 (s, 3H), 3.
73 (t, 2H), 4.25 (t, 2H), 7.29
(M, 1H), 7.42 (m, 2H), 7.52 (m,
1H), 7.75 (m, 2H), 7.81 (m, 2H) In addition to this, peaks believed to be derived from NH are δ 3.32.
It appeared in the vicinity of (s, 1H) and 9.02 (s, 1H). Results of IR measurement (KBr tablet method) (only characteristic absorption) 1725 cm ^-1 (derived from carbonyl group of urea group) 1692 cm ^-1 (derived from carbonyl group of ester group) 1343, 1158 cm ^-1 (derived from sulfonyl group)

<Synthesis Example 4>N-phenyl-N'-3-
Synthesis of (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea (chemical formula (XI)): (1) Intermediate material N-3-p-nitrophenylpropyl-
Synthesis of N'-phenylurea In a three-necked flask equipped with a thermometer, a reflux tube, and a dropping funnel, 3.0 g of 3-amino-1-propanol and 80 m
1 l of tetrahydrofuran was added, and 5.9 g of phenyl isocyanate dissolved in 20 ml of tetrahydrofuran was added from a dropping funnel at room temperature while stirring with a magnetic stirrer. The reaction proceeded immediately after the addition of phenyl isocyanate to cause white precipitation, but the mixture was further stirred for 2 hours to complete the reaction. The white solid was filtered, washed with water, and then purified by a recrystallization method to obtain 8.1 g of white crystals. Next, into a three-necked flask equipped with a thermometer, a reflux tube, and a dropping funnel, 5.0 g of the white crystals obtained by the above-mentioned operation and 120 ml of tetrahydrofuran were placed, and 2.8 g of them was added thereto.
Of triethylamine was added. 3. This mixture was stirred with a magnetic stirrer and p-nitrobenzoyl chloride dissolved in 20 ml of tetrahydrofuran.
8 g was added from the dropping funnel. The reaction proceeded as soon as the tetrahydrofuran solution of p-nitrobenzoyl chloride was added, and triethylamine hydrochloride separated and precipitated, but the solution was further stirred at room temperature for 4 hours in order to complete the reaction. When the reaction solution was added to 800 ml of water and vigorously stirred, triethylamine hydrochloride was dissolved, and instead a white solid of the desired product was precipitated. This white solid was filtered and purified by a recrystallization method to obtain 7.4 g of white crystals. The analytical values of this white crystal are as follows.

Melting point: 135 ° C. NMR measurement result (in CDCL ₃ ) (number is ppm) δ1.91 (m, 2H), 3.25 (m, 2H), 4.
37 (t, 2H), 6.84 (t, 1H), 7.18
(D, 2H), 7.34 (d, 2H), 7.83 (d,
2H), 8.30 (d, 2H) In addition to this, the peak that is thought to be due to NH is δ6.24.
It appeared near (m, 1H) and 8.43 (s, 2H). Results of IR measurement (KBr tablet method) (only characteristic absorption) 1688 cm ^-1 (derived from carbonyl group of ester group) 1735 cm ^-1 (derived from carbonyl group of urea group) 3122 cm ^-1 (derived from amino group of urea group)

(2) N-phenyl-N'-3- (4-p
-Toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea (chemical formula (XI)) 7.0 g of N-3-p-nitrophenylpropyl-N'-phenylurea was placed in an autoclave, and 80 ml of tetrahydrofuran and 5 wt% -Pd were added. / C 3.5g was added. After replacing the inside of the autoclave with hydrogen, the internal pressure was adjusted to 2 atm and the mixture was stirred for 2 hours to reduce the nitro group. Pd / C is removed by filtration, the solvent is distilled off, and 6.
2 g of white solid was obtained. Next, in a three-necked flask equipped with a dropping funnel, a thermometer, and a reflux tube, 6.2 g of the white solid obtained by the above operation was put, 200 ml of toluene was added thereto, and the mixture was stirred with a magnetic stirrer, from the dropping funnel, 4.0 g of p-toluenesulfonyl isocyanate was added dropwise at room temperature. Continued stirring of the reaction mixture caused a large amount of white solid to precipitate. The reaction mixture was heated under reflux at 120 ° C. for 2 hours, cooled, and filtered to obtain 10.0 g of white crystals. The analytical values of this white crystal are as follows.

Melting point: 158 ° C. Results of NMR measurement (in heavy DMSO) (numbers are ppm) δ 1.85 (m, 2H), 2.39 (s, 3H), 3.
22 (m, 2H), 4.26 (t, 2H), 6.86
(M, 1H), 7.19 (m, 2H), 7.35 (d,
2H), 7.42 (d, 2H), 7.45 (d, 2)
H), 7.86 (m, 4H) In addition to this, the peak that seems to be due to NH is δ3.33.
(S, 1H), 6.22 (m, 1H), 8.42 (s,
1H) and 9.22 (s, 1H). Results of IR measurement (KBr tablet method) (only characteristic absorption) 1719, 1723 cm ^-1 (derived from carbonyl group of urea group) 1687 cm ^-1 (derived from carbonyl group of ester group) 1343, 1157 cm ^-1 (derived from sulfonyl group) <Synthesis example 5> Synthesis of butyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate (1) Intermediate raw material Synthesis of butyl aminobenzenesulfonate In a three-necked flask equipped with a thermometer, a reflux tube, and a dropping funnel. 4 g of p-sulfanilamide and 120 ml of N, N-diaminoacetamide were added, and 2.8 g of potassium carbonate (anhydrous) was added to the solution. 1. Stir this mixture with a magnetic stirrer at room temperature.
7 g of 1-bromobutane was added. After cooling this reaction suspension at room temperature, the reaction suspension was added to 800 ml of water and vigorously stirred to precipitate a white solid. This white solid was filtered and purified by a recrystallization method to obtain 4.1 g of white crystals. This white crystal was confirmed to be the target compound by various instrumental analyzes. (2) Synthesis of butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate To a three-necked flask equipped with a dropping funnel, a thermometer, and a reflux tube, 3.4 g of butylaminobenzenesulfonate was placed, and 200 ml of toluene was added thereto. The mixture was added and stirred to dissolve butyl aminobenzene sulfonate. While stirring this mixed solution with a magnetic stirrer, 3.4 g of p-toluenesulfonyl isocyanate was added dropwise from the dropping funnel at room temperature. Continued stirring of the reaction mixture caused a large amount of white solid to precipitate. This reaction mixture is mixed with 70
By heating at ℃ for 2 hours, cooling and filtering, 5.8
White crystals of g were obtained. This white crystal was confirmed to be the target compound by various instrumental analyzes.

<Example 1> A thermal recording paper was prepared by the following operation. (1) Preparation of Pigmented Undercoat Paper Styrene-butadiene copolymer emulsion (solid content 50%) in a dispersion obtained by dispersing 85 parts of calcined clay (trade name: Ansilex, Engelhard Minerals) in 320 parts of water. 40 parts, 50% 10% oxidized starch aqueous solution
The coating liquid obtained by partial mixing was applied onto a base paper of 48 g / m ² so that the coating amount after drying was 7.0 g / m ² to obtain a pigment-undercoated paper.

(2) Preparation Component of Dispersion A Content (parts) 3- (N, N-dibutylamino) -6-methyl-7-anilinofluorane 20 Polyvinyl alcohol 10% liquid 10 Water 70 The above composition Was pulverized using a sand grinder until the average particle diameter became 1 μm or less.

(3) Preparation of Dispersion Liquid Amount (part) 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (chemical formula (VIII)) 20 Polyvinyl alcohol 10% liquid 10 Water 70 The above composition was pulverized using a sand grinder until the average particle size became 1 μm or less.

(4) Preparation of Dispersion C Content (part) Oxalic acid di-p-methylbenzyl ester 20 Polyvinyl alcohol 10% liquid 10 Water 70 The above composition was used with a sand grinder to have an average particle size of 1 μm or less. Crushed until

(5) Formation of Coloring Layer 60 parts of solution A, 120 parts of solution B, 120 parts of solution C, 23 parts of kaolinite pigment (HG clay manufactured by Huber), 25%
20 parts zinc stearate dispersion, 15 parts 30% paraffin dispersion, and 10% aqueous polyvinyl alcohol solution 1
20 parts were mixed and stirred to obtain a coating liquid. This coating solution
One side of the pigment-coated paper has a coating amount of 5.0 g / m after drying.
^A thermosensitive color developing layer was formed by applying and drying so as to give a thermosensitive recording paper.

(6) Super calender treatment The thermal recording paper obtained as described above was treated with a super calender to obtain a Beck smoothness of 800 on the surface.
~ 1000 seconds.

(7) Various tests (a) Whiteness The whiteness of the above thermal recording paper sample was measured using a Hunter whiteness meter (manufactured by Toyo Seiki Seisakusho). (B) Color development test The thermal recording paper thus obtained was tested for dynamic thermal color development simulator THPMD (printing voltage 21.7) manufactured by Okura Electric Co., Ltd.
V) was used to color the sample in a checkered pattern under the printing condition of an applied pulse width of 1.0 ms. The color density was measured with a Macbeth reflection densitometer RD-914, and this was used as a representative value of recording sensitivity.

(C) Heat resistant background color development test of blank paper part The above heat sensitive recording paper sample was placed in a thermostat at 60 ° C. for 24 hours, and the density of the blank paper part was measured in the same manner as in (b) above. (D) White Paper Moisture-Resistant Coloring Test The thermosensitive recording paper sample was placed in a thermo-hygrostat controlled at 40 ° C. and 90% RH for 24 hours, and the density of the white paper portion was measured in the same manner as in (b) above.

<Example 2> The same operation as in Example 1 was performed. However, in the preparation of the dispersion liquid B, N-3- was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide (chemical formula (X)) was used. The test results are shown in Table 1. <Example 3> The same operation as in Example 1 was performed. However,
In preparing Dispersion B, 4- [4- (4-i was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
so-propoxyphenylsulfonyl) phenoxy)]
Butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (formula IX) was used. The test results are shown in Table 1. <Example 4> The same operation as in Example 1 was performed. However,
In preparing the dispersion liquid B, N-phenyl-N ′ was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea (Chemical formula XI)
Was used. The test results are shown in Table 1. <Example 5> The same operation as in Example 1 was performed. However,
In the preparation of Dispersion B, butyl 4-p-toluenesulfonylaminocarbonylaminobenzenesulfonate was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate. The test results are shown in Table 1. <Example 6> The same operation as in Example 1 was performed. However,
In preparing the dispersion liquid B, instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, dipropyl 4-p
-Toluenesulfonylaminocarbonylaminobenzenephosphonate was used. The test results are shown in Table 1.

Comparative Example 1 The same operation as in Example 1 was performed. However, in the preparation of the dispersion liquid B, instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 2,2-
Bis (4-hydroxyphenyl) propane (bisphenol A) was used. Table 1 shows the results of the basic performance tests (a), (b), (c) and (d) as a thermal recording material.

[0068]

[Table 1] As is clear from Table 1, the thermosensitive recording medium of the present invention has high whiteness and high color development performance, and suppresses the white color development of the white paper portion under a high temperature and high humidity atmosphere, and is required for the thermal recording medium. It has basic performance.

Example 7 A thermosensitive recording paper was prepared by the following operation. (1) Preparation of Pigment Undercoat Paper Pigment undercoat paper was produced by the same method as in Example 1 (1). (2) Preparation amount of dispersion liquid A (part) 3- (N, N-dipentylamino) -6-methyl-7-anilinofluorane 10 Oxalic acid di-p-methylbenzyl ester 8 Oxalic acid di- p-Chlorobenzyl ester 2 Polyvinyl alcohol 10% liquid 10 Water 70 The above composition was pulverized using a sand grinder until the average particle size became 1 μm or less.

(3) Preparation Component of Dispersion B Component (part) 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (chemical formula (VIII)) 30 Polyvinyl alcohol 10% liquid 10 Water 70 Above The composition was pulverized using a sand grinder until the average particle size became 1 μm or less.

(5) Formation of Coloring Layer 20 parts of the above solution A, 30 parts of solution B, 40 parts of 50% kaolinite pigment (HG clay manufactured by Huber), 3 parts of 35% zinc stearate dispersion, and 10% 8 parts of a polyvinyl alcohol aqueous solution were mixed and stirred to obtain a coating liquid. This coating liquid is applied to one side of a pigment-undercoated paper at a coating amount of 5.0 g after drying.
/ M ² to form a thermosensitive coloring layer by drying.
A thermal recording paper was prepared.

(7) Various tests (e) High heat resistant background color development test The thermosensitive recording paper obtained as described above was used as a dynamic thermosensitive color development simulator THPMD (printing voltage 21.7) manufactured by Okura Electric.
V), a checkerboard pattern was formed under a printing condition of an applied pulse width of 1.0 ms, the plate was placed in a thermostat at 100 ° C. for 1 hour, and the density of the background was measured with a Macbeth reflection densitometer RD-914. Further, the contrast between the recorded portion and the background portion was visually observed. Table 2 shows the test results of the high heat resistant ground color test (e).
Table 3 shows the test results of the plasticizer resistance test (f).

<Example 8> The same operation as in Example 7 was performed. However, in the preparation of the dispersion liquid B, N-3- was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
(3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide (chemical formula (X)) was used. The test results are shown in Table 2. <Example 9> The same operation as in Example 7 was performed. However,
In the preparation of the dispersion liquid B, 4- [4- (4-is is used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
o-Propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate (formula IX) was used. The test results are shown in Table 2. <Example 10> The same operation as in Example 7 was performed. However, in preparing the dispersion liquid B, N-phenyl- was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
N'-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea (chemical formula
XI) was used. The test results are shown in Table 2. <Example 11> The same operation as in Example 7 was performed. However, in the preparation of the dispersion liquid B, butyl 4-p- was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
Toluenesulfonylaminocarbonylaminobenzenesulfonate was used. The test results are shown in Table 2. <Example 12> The same operation as in Example 7 was performed. However, in the preparation of the dispersion liquid B, butyl dipropyl 4-p-toluenesulfonylaminocarbonylaminobenzenephosphonate was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate. The test results are shown in Table 2. <Comparative Example 2> The same operation as in Example 7 was performed. However,
In the preparation of Dispersion B, p-toluenesulfonylaminocarbonylaminobenzene was used in place of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate. The test results are shown in Table 2.

Comparative Example 3 The same operation as in Example 7 was performed. However, in the preparation of the dispersion liquid B, butyl was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate.
p-Toluenesulfonylaminocarbonylaminobenzoate was used. The test results are shown in Table 2. <Comparative Example 4> The same operation as in Example 7 was performed. However,
In preparing Dispersion B, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) was used instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate. The results are shown in Table 2.

[0075]

[Table 2] As shown in Table 2, in a high temperature environment corresponding to the inside of a car in the summer hot weather, Comparative Examples 2, 3 and 4 caused intense ground coloration, and the recorded image became indistinguishable, while the developed color of the present invention. The recorded images can be read well in Examples 7 and 8 using the agent.

(F) Plasticizer resistance test 1.0 m in the same manner as the thermal recording paper used in the high heat resistant ground color development test (e) of Examples 7, 8, 9, 10, 11 and 12.
The sample colored with s was sandwiched from the top and bottom with a vinyl chloride film (made by Mitsubishi Plastics, the vinyl chloride film belongs to the group with the largest plasticizer content in the plastic film for packaging) so that it will be 10 gf / cm ^2. After a load was applied and the mixture was left in a thermostat at 100 ° C. for 17 hours, the vinyl chloride film was peeled off, the residual image density was measured by a Macbeth reflection densitometer, and the image preservation rate was calculated according to the following formula. Further, the contrast between the recorded portion and the background portion was visually evaluated. Image preservation rate (%) = [density after plasticizer resistance test / original density] × 10
0 results are shown in Table 3.

<Comparative Example 5> The same operation as in Example 7 was performed. However, in the preparation of the dispersion liquid B, instead of 3-p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 2,2-
Bis (4-hydroxyphenyl) propane (bisphenol A) was used. The results are shown in Table 3.

[0078]

[Table 3] As is clear from Table 3, in Comparative Example 5, the recorded image is erased by contact with the vinyl chloride film and becomes unreadable, whereas in Example 7 using the color developer of the present invention,
8, 9, 10, 11 and 12 hold the recorded image,
Good readability.

It should be noted that 3-in the formula (VIII)
p-toluenesulfonylpropyl 4-p-toluenesulfonylaminocarbonylaminobenzoate, 4- [4- (4-iso-propoxyphenylsulfonyl) phenoxy)] butyl 4 represented by the chemical formula (IX).
-P-toluenesulfonylaminocarbonylaminobenzoate, N-3- (3- represented by the above chemical formula (X)
p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide, and N-phenyl-N′-3- (4-p-represented by the chemical formula (XI).
Toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea is a compound whose structure has been clearly determined by various analytical methods.

[0080]

INDUSTRIAL APPLICABILITY The heat-sensitive recording material of the present invention has, in its heat-sensitive color-developing layer, the compounds represented by formulas (I), (II) and (II) as a developer.
Since at least one member selected from the organic compounds represented by I) is used, it exhibits high whiteness and high color development performance, and is harsh enough to be cooked in a car in hot and humid atmospheres, especially in the hot summer weather, or in a microwave oven. Even under a wide variety of environments, there is almost no background color development, and high color image storability is exhibited. Further, as a developer in the thermosensitive coloring layer,
The heat-sensitive recording material of the present invention containing at least one member selected from the organic compounds represented by the general formulas (I), (II) and (III) is excellent even when contacted with a plasticizer or a vinyl chloride film. It shows high storability of color image. The present invention is a thermosensitive recording medium which is free from the disappearance of an image once colored and has excellent storage stability of recording and high recording sensitivity. The thermal recording material of the present invention has good long-term storage stability of recording,
At the same time, the heat resistance of the recorded image, especially in the car in the hot summer
Or, assuming heating and cooking with a microwave oven,
Heat resistance under higher temperature conditions, environment resistance such as humidity resistance,
Furthermore, it has excellent chemical resistance such as oil resistance and plasticizer resistance, high recording sensitivity and whiteness, and is representative of cash dispenser paper, ticket, pass ticket, parking ticket, admission ticket, commuter pass, and POS label. It is useful for labels that are used and cards such as prepaid cards. The thermosensitive recording medium of the present invention contains, as a color developer, an organic compound in which Z ₁ of the general formula (I) is a sulfonyl group substituted by at least one member selected from an alkyl group, an aryl group or an aralkyl group. In the case where Z ₁ is a cyclic imide group and contains an organic compound in which the nitrogen atom of the cyclic imide group is bonded to Y ₁ , or when Z ₁ contains an organic compound which is a urea group. In particular, it showed excellent heat resistance and plasticizer resistance.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshiyuki Takahashi             Made by Oji 1-10-6 Shinonome, Koto-ku, Tokyo             Paper Co., Ltd. Shinonome Research Center F term (reference) 2H026 AA05 BB24                 4C204 BB05 BB09 CB04 EB03 FB17                       GB01                 4H006 AA01 AA03 AB76 TA02 TB13                       TB32 TB42 TC37

Claims (7)

[Claims] 1. A sheet-shaped substrate, a colorless or light-colored dye precursor which is formed on at least one surface of the substrate, and a developer which reacts with the dye precursor under heating to develop a color. In a thermosensitive recording material having a thermosensitive coloring layer,
As the color developer, the following general formulas (I), (II) and (II
A thermosensitive recording medium comprising at least one compound selected from the compounds represented by I). [Chemical 1] (In the formula, R ₁ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and X ₁ represents an oxygen atom. Alternatively, a sulfur atom, Y ₁ represents a divalent group containing two or more carbon atoms, and Z ₁ represents a monovalent group having at least one hetero atom, and Z ₁ is a sulfonylurea (—SO ₂ NHCON
H-) group is excluded. The number of —COOY ₁ Z ₁ groups may be 1 or 2 or more on the benzene ring. When there are two or more, a plurality of —COOY ₁ Z ₁ groups may be the same or different. ) [Chemical 2] (In the formula, R ₂ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and R ₃ is a monovalent group. And an X ₂ represents an oxygen atom or a sulfur atom, and one or more —SO ₂ OR ₃ groups may be present on the benzene ring. -SO ₂ O
The R ₃ groups may be the same or different. ) [Chemical 3] (In the formula, R ₄ represents at least one member selected from a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted aliphatic hydrocarbon group (including an alicyclic group), and R ₅ and R ₆ represent independently of one another a monovalent organic residue, also, X ₃ represents an oxygen atom or a sulfur atom.-PO ₃ (R ₅₎
There may be one or two or more (R ₆ ) groups on the benzene ring. If two or more, a plurality of _{-PO 3 (R 5) (R} 6)
The groups may be the same or different. ) 2. The thermosensitive recording medium according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the following general formula (IV). [Chemical 4] (In the formula, R ₇ represents an unsubstituted aromatic hydrocarbon group, or an aromatic hydrocarbon group substituted by at least one member selected from an alkyl group, an alkoxyl group, or a halogen atom, and Y ₂ represents Represents a divalent group containing two or more carbon atoms, Z ₂ is a sulfonyl group substituted by at least one member selected from an alkyl group, an aryl group, or an aralkyl group; or an alkyl group, an aryl group, or an aralkyl group. from representing at least part by a substituted imide group selected.-COOY ₂ Z ₂ groups in the case of 1 or 2 or more was .2 or more may be on the benzene ring, a plurality of -COOY ₂ Z ₂ The groups may be the same or different.) 3. The compound represented by the general formula (I) is at least one compound selected from the group of compounds represented by the following general formulas (V), (VI) and (VII). 1. The heat-sensitive recording material according to 1. [Chemical 5] (In the formula, R ₈ is an unsubstituted aromatic hydrocarbon group, or a methyl group, a methoxy group, or an aromatic hydrocarbon group substituted by at least one member selected from chlorine atoms, R 8
₉ represents a member selected from a hydrogen atom, a chlorine atom, a nitro group, an alkyl group, an alkoxyl group, an aryl group, an aryloxy group, an aralkyl group and an aralkyloxy group,
Two or more may be independently substituted on the benzene ring, and Y ₃ represents a divalent group containing 2 or more carbon atoms. The number of ester groups having Y ₃ may be 1 or 2 or more on the benzene ring. When there are two or more, the plurality of ester groups having Y ₃ may be the same or different. ) [Chemical 6] (In the formula, R ₁₀ represents an unsubstituted aromatic hydrocarbon group, or an aromatic hydrocarbon group substituted by at least one member selected from a methyl group, a methoxy group, or a chlorine atom,
R ₁₁ and R ₁₂ may independently form a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, or, together, form a cyclopentane ring, a cyclohexane ring, a dicyclopentane ring, or a benzene ring. , Y ₄ represents a divalent group containing two or more carbon atoms. The number of ester groups having Y ₄ may be 1 or 2 or more on the benzene ring. When there are two or more, the plurality of ester groups having Y ₄ may be the same or different. ) [Chemical 7] (In the formula, R ₁₃ represents an unsubstituted aromatic hydrocarbon group, or a methyl group, a methoxy group, or an aromatic hydrocarbon group substituted by at least one member selected from chlorine atoms;
₁₄ represents a member selected from an alkyl group, an aryl group and an aralkyl group, and Y ₅ represents a divalent group containing 2 or more carbon atoms. The number of ester groups having Y ₅ may be 1 or 2 or more on the benzene ring. If two or more,
The plural ester groups having Y ₅ may be the same or different. ) 4. The following chemical formula (VIII): 3-p-toluenesulfonylpropyl represented by
4-p-toluenesulfonylaminocarbonylaminobenzoate, the following chemical formula (IX): 4- [4- (4-iso-propoxyphenylsulfonyl) phenoxy)] butyl 4-p-toluenesulfonylaminocarbonylaminobenzoate represented by the following chemical formula (X): N-3- (3-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylphthalimide represented by: and the following chemical formula (XI): N-phenyl-N′-3- (4-p-toluenesulfonylaminocarbonylaminobenzoyloxy) propylurea represented by 5. The general formula (VIII) or (I according to claim 4)
X), (X) and at least one compound selected from compounds represented by (XI). 6. A color developing agent containing at least one compound selected from the compounds represented by formulas (I), (II) and (III) according to claim 1. 7. A thermosensitive recording medium comprising the color developer according to claim 5.