JPH06227139A - Production of thermal recording body - Google Patents

Abstract

PURPOSE:To enhance whiteness degree, various durabilities and color development properties by coating or printing a supporting body with a solution containing at least one kind selected from among three kinds of dye precursors shown in the specified respective formulas, a colorant, resin soluble into an organic solvent and the organic solvent. CONSTITUTION:In the case of producing a thermal recording body, at least one kind is selected from three kinds of dye precursors shown in the respective formulas mentioned elsewhere and used. On one side, a solution containing a colorant for coloring the dye precursors, resin soluble in an organic solvent and the organic solvent is used. A supporting body is coated or printed with the solution. For example, as the respective dye precursors, a compound wherein a substituent shown in Ra, Rb, Rc, Rd is tert-butyl group is preferably used because color development properties in particular are excellent. Thereby the thermal recording body is obtained which is high in whiteness degree, excellent in resistance to chemicals, resistance to plasticity and water resistance and also excellent in color development properties.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a heat-sensitive recording material, and particularly to a method for producing a heat-sensitive recording material having high whiteness, excellent chemical resistance, plasticity resistance and water resistance, and excellent color development. Regarding

[0002]

2. Description of the Related Art A thermosensitive recording medium is known in which a color-forming substance is brought into contact with heat to obtain a recorded image by utilizing a coloring reaction between a colorless or light-colored dye precursor and an organic or inorganic acidic substance. There is. In recent years, with the remarkable progress of the thermal recording system, its fields of use and forms are diversifying, and not only as a recording medium for a thermal facsimile or a thermal printer, but also a magnetic thermal paper, a POS label, or a ticket card that requires forgery prevention. There is a rapid increase in the use for new applications such as products, prepaid cards, and sealless fixed terms.

However, a thermal recording material is generally included in the synthetic resin if the image portion is discolored by fingerprints, diazo copy, cellophane tape, felt-tip pen, ink or the like after recording, or if it is in contact with the synthetic resin product for a long time. The plasticizer has a drawback such as discoloration or color development of the white paper portion, which significantly impairs its commercial value, and its improvement is strongly demanded.

For this purpose, an attempt has been made to improve the above-mentioned drawbacks caused by chemicals and plasticizers by providing a water-soluble polymer protective layer on the heat-sensitive recording layer.
Partly used for labels, tickets, etc. However, since the water-soluble polymer protective layer is provided, the water resistance is inferior, and a satisfactory thermal recording material has not always been obtained. On the other hand, in a general thermosensitive recording medium having no protective layer, the storability of a recorded image as described above and the water resistance are poor because a water-soluble polymer is used as an adhesive, and the thermosensitive recording layer due to contact with water. This is a major drawback because peeling or elution of

In order to improve such a defect, it has been attempted to make a recording layer contain a specific dye precursor and a melting point depressant in an organic solvent as a medium, and in some cases, to form a protective layer by coating in an organic solvent as a medium. (Japanese Patent Laid-Open No. 63-31
5290 publication). However, this particular dye precursor used is industrially expensive and not always an advantageous method.

Further, a heat-sensitive recording material generally obtained by using an organic solvent as a medium has a drawback that its whiteness is low and its commercial value is remarkably lowered.

[0007]

DISCLOSURE OF THE INVENTION The present invention has improved the above-mentioned various drawbacks and has a high whiteness, no discoloration of the image area due to chemicals or plasticizers, no color development of the blank area, and contact with water. It is intended to provide a method for producing a high-sensitivity thermosensitive recording medium which is excellent in water resistance and does not cause peeling or elution of a coating layer.

[0008]

The present invention provides a support,
At least one dye precursor selected from the group of [Chemical Formula 1], [Chemical Formula 2], and [Chemical Formula 3], a coloring agent capable of coloring the dye precursor, an organic solvent-soluble resin, and an organic compound. A method for producing a heat-sensitive recording material, which comprises applying or printing a coating liquid containing a solvent.

[0009]

[Chemical 1]

[Wherein R_aIs C_Four~ C₁₂The tertiary alkyl
Group, R₁~ R₁₁Are hydrogen atom and halogen atom respectively
Child, C₁~ C₁₂Alkyl group of C₁~ C₁₂The alkoxy
Group, hydroxyl group, nitro group, -N (R₁₂) (R₁₃), -O
(CO) OR₁₄, Or -O (CO) R₁₅Indicates. However,
R₁₂, R₁₃Are hydrogen atoms; C₁~ C₁₂The alkyl
Group; C_Four~ C₁₂Cycloalkyl group; halogen atom, C
₁~ C₆Alkyl group of C₁ ~ C₆Set with the alkoxyl group of
Optionally substituted aralkyl group; halogen atom, C₁~
C₆Alkyl group of C₁~ C₆Substituted with an alkoxyl group
Represents an optionally substituted aryl group, R₁₂And R₁₃Are adjacent
Pyrrolidino group, piperidino group or hex with nitrogen atom
A Samethyleneimino group may be formed. Also, R₁₄Is C
₁~ C₁₂Alkyl group; benzyl group; halogen atom, C
₁~ C₆Alkyl group of C₁~ C₆With the alkoxyl group of
An aryl group which may be substituted, R₁₅Is C₁~ C₁₂
Alkyl group; benzyl group; halogen atom, C₁~ C₆
Alkyl group of C₁~ C₆Substituted with an alkoxyl group of
Optionally an aryl group, -N (R₁₆) (R₁₇) Is shown. still,
R₁₆, R₁₇Are hydrogen atoms; C₁~ C₁₂The alkyl
Group; C_Four~ C₁₂Cycloalkyl group; halogen atom, C
₁~ C₆Alkyl group of C₁~ C₆With the alkoxyl group of
Optionally substituted aralkyl group; halogen atom, C₁
~ C₆Alkyl group of C₁~ C₆Set with the alkoxyl group of
An aryl group which may be replaced is represented by R ₁₆And R₁₇Is adjacent
Pyrrolidino group, piperidino group or
Hexamethyleneimino groups may be formed. ]

[0011]

[Chemical 2]

[In the formula, R _b represents a C _{4 to} C ₁₂ tertiary alkyl group, and R _{18 to} R ₃₀ represent a hydrogen atom, a halogen atom, a C _{1 to} C ₁₂ alkyl group, and a C _{1 to} C _{12 respectively.} Alkoxyl group, hydroxyl group, -O (CO) OR ₃₁ or -O (CO)
R ₃₂ is shown. However, R ₃₁ and R ₃₂ represent a C _{1 to} C ₁₂ alkyl group; a benzyl group; a halogen atom, a C _{1 to} C ₆ alkyl group, and an aryl group which may be substituted with a C _{1 to} C ₆ alkoxyl group. . ]

[0013]

[Chemical 3]

[Wherein R_c, R_dAre each C_Four~ C₁₂
Represents a tertiary alkyl group. X and Y are NR₄₁,
Or S is shown, but X and Y may be bonded in the form of N--A--N.
Good. Where R₄₁Is a hydrogen atom, C₁~ C_TenThe alkyl
Group, -COR₄₂Or -COOR ₄₃And A is C₁~ C
_TenIs a saturated or unsaturated alkylene group. Also, R
₄₂, R₄₃Are each C₁~ C₁₂Alkyl group of benzyl
Group; halogen atom, C₁~ C₆Alkyl group of C₁~ C
₆Represents an aryl group which may be substituted with an alkoxyl group of
You Also, R₃₃~ R₄₀Are hydrogen atom and halogen atom respectively
Child, C₁~ C_TenAlkyl group of C₁~ C_TenThe alkoxy
Group, nitro group, -N (R₄₄) (R₄₅), Or -SR₄₆To
Show. Incidentally, R₃₃And R₃₄, R₃₄And R₃₅, R₃₅And R₃₆, R₃₇
And R₃₈, R ₃₈And R₃₉, R₃₉And R₄₀Are benzene rings
May be formed. Where R₄₄, R₄₅Are each hydrogen
Atom; C₁~ C₁₂Alkyl group of C_Four~ C₁₂Cycloa
Rualkyl group; halogen atom, C₁~ C₆Alkyl group of C
₁~ C₆Which may be substituted with an alkoxyl group of
Kill group; halogen atom, C₁~ C₆Alkyl group of C ₁
~ C₆Aryl group which may be substituted with an alkoxyl group of
, But R₄₄And R₄₅Together with the adjacent nitrogen atom
A dino group, piperidino group or hexamethyleneimino group
You may form. Also, R₄₆Is C₁~ C_TenAlkyl group of
Indicates. ] In the present invention, the organic solvent-soluble resin,
The thermosensitive recording medium containing a resin soluble in an organic solvent but insoluble in water
A method of manufacturing the same is disclosed.

[Chemical formula 1], [Chemical formula 2] and [Chemical formula 3]
By the way, R_a, R_b, R_c, And R _dIs a tert-butyl group
A method of manufacturing a thermosensitive recording medium is disclosed. Furthermore, organic dissolution
Medium is alcohols, ketones, esters, aliphatic carbonization
It consists of hydrogen, naphthenic hydrocarbons, and aromatic hydrocarbons.
Of at least one thermosensitive recording material selected from the group
A manufacturing method is disclosed.

[0016]

The heat-sensitive recording material according to the present invention has improved water resistance by using an organic solvent-soluble resin and an organic solvent, and can prevent peeling or elution of the heat-sensitive recording layer due to contact with water. It has the advantage that it can be used outdoors. In the heat-sensitive recording material of the present invention, a protective layer may be provided on the above-mentioned heat-sensitive recording layer, and particularly in a constitution in which a protective layer containing a resin soluble in an organic solvent is provided, further excellent water resistance, Weather resistance can be obtained.

The dye precursor represented by [Chemical Formula 1], [Chemical Formula 2] or [Chemical Formula 3] is colorless or light in itself, but develops color when heated at a high temperature. However, the use of a coloring agent such as an organic or inorganic acidic substance has the characteristics that the color development temperature can be lowered and a robust image can be obtained. Incidentally, the usual dye precursor and the color developing agent cause remarkable fog coloration when they are brought into contact with an organic solvent.

Further, the heat-sensitive recording material of the present invention has an important feature in that at least one of such compounds is used as a dye precursor constituting the heat-sensitive recording layer, and such a structure is adopted. In addition, a high-sensitivity heat-sensitive recording material having high whiteness and not causing discoloration of the image area or fogging of the white paper area even when stored in a high temperature or high humidity environment is obtained.

The reaction between these dye precursors and the color former is
Since it is an irreversible reaction that usually involves decarboxylation and does not return to a colorless compound, it is considered that it does not deteriorate due to heat, humidity, or a plasticizer. In addition, it is presumed that a stable tertiary carbonium ion is produced as an intermediate during decoloration in the color reaction, which is considered to give a highly sensitive recording material.

Specific examples of the dye precursor represented by the general formula [Chemical Formula 1], [Chemical Formula 2] or [Chemical Formula 3] are shown below. Among these, R _a , R _b , R _c , and A compound in which the substituent represented by R _d is a tert-butyl group is more preferably used because a thermosensitive recording material having particularly excellent color developability can be obtained.

The following can be exemplified as [Chemical Formula 1]. 3,6-di (tert-butoxycarboxy) fluorane, 3,6-di (1,1-dimethylpropoxycarboxy) fluorane, 3,6-di (1-methyl-1-ethylbutoxycarboxy) fluorane, 3,6 -Di (tert-
Butoxycarboxy) -4,5-dimethylfluorane,
3,6-di (tert-butoxycarboxy) -1,8-dimethylfluorane, 3,6-di (tert-butoxycarboxy) -2,7-diethylfluorane, 3,6-di (te
rt-Butoxycarboxy) -1,5-diethylfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -2,7-diethylfluorane, 3,6-di (tert.
-Butoxycarboxy) -2,4,3,6-di (tert-
Butoxycarboxy) -4,5-dinitrofluorane,
3,6-di (tert-butoxycarboxy) -2,7-didecylfluorane, 3,6-di (tert-butoxycarboxy) -2-dodecyl-8-methylfluorane, 3,6
-Di (tert-butoxycarboxy) -6'-butoxyfluorane, 3,6-di (tert-butoxycarboxy)-
4'-methoxyfluorane, 3,6-di (tert-butoxycarboxy) -4'-decaoxyfluorane, 3-
(Tert-butoxycarboxy) -6-methoxyfluorane, 3- (tert-butoxycarboxy) -7-methoxyfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -6'-butoxyfluorane, 3- (tert
-Butoxycarboxy) -6-ethoxy-2,7-dioctylfluorane, 3- (1,1-dipropylbutoxycarboxy) -2,4,5,7-tetrachlorofluorane, 3,6-di (tert -Butoxycarboxy) -2,
4,5,7-Tetrabromofluorane, 3,6-di (te
rt-Butoxycarboxy) -2,4,5,7-tetraiodofluorane, 3,6-di (tert-butoxycarboxy) -1,8-dimethyl-3 ′, 4 ′, 5 ′, 6′-tetra Chlorofluorane, 3,6-di (tert-butoxycarboxy) -3 ', 4', 5 ', 6'-tetrabromofluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -2, 7-dibromofluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -4,5-
Dinitrofluorane, 3,6-di (1,1-diethylhexaoxycarboxy) -3 ', 4', 5 ', 6'-tetrachlorofluorane, 3,6-di (tert-butoxycarboxy) -2 , 7-Dibromofluorane, 3,6-di (tert-butoxycarboxy) -4,5-dinitrofluorane, 3,6-di (tert-butoxycarboxy)-
2,7-Didecylfluorane, 3,6-di (tert-butoxycarboxy) -2-dodecyl-8-methylfluorane, 3,6-di (tert-butoxycarboxy) -6'-
Butoxyfluorane, 3,6-di (tert-butoxycarboxy) -4'-methoxyfluorane, 3,6-di (te
rt-Butoxycarboxy) -4′-decaoxyfluorane, 3- (tert-butoxycarboxy) -6-methoxyfluorane, 3- (tert-butoxycarboxy) -7-
Methoxyfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -6'-butoxyfluorane, 3
-(Tert-butoxycarboxy) -6-ethoxy-2,
7-Dioctylfluorane, 3- (1,1-dipropylbutoxycarboxy) -6-methoxyfluorane, 3-
(Tert-Butoxycarboxy) -6-ethoxy-2,7
-Dibenzylfluorane, 3- (tert-butoxycarboxy) -6-methoxycarboxyfluorane, 3- (te
rt-Butoxycarboxy) -7-methoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminofluorane, 3-
(Tert-Butoxycarboxy) -6-diethylaminofluorane, 3- (tert-butoxycarboxy) -7-diethylaminofluorane, 3- (tert-butoxycarboxy) -6-dibutylaminofluorane, 3- (tert-
Butoxycarboxy) -6-didodecylaminofluorane, 3- (tert-butoxycarboxy) -6-piperidinofluorane, 3- (tert-butoxycarboxy) -6
-(N-ethyl-N-isopentyl) aminofluorane, 3- (tert-butoxycarboxy) -6- (N-cyclohexyl-N-methyl) aminofluorane, 3-
(Tert-butoxycarboxy) -6-phenoxycarboxyfluorane, 3- (tert-butoxycarboxy)-
6-benzyloxycarboxyfluorane, 3- (1,
1-dimethylhexaoxycarboxy) -6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-butylcarboxyfluorane, 3- (tert
-Butoxycarboxy) -6-phenylcarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminocarboxyfluorane.

The following can be exemplified as [Chemical Formula 2]. O, O′-di (tert-butoxycarbonyl) phenolsulfophthalein, O, O′-di (tert-butoxycarbonyl) -3,3′-dimethylphenolsulfophthalein, O, O′-di (tert- Butoxycarbonyl)
-2,2'-Dimethyl-5,5'-diisopropylphenolsulfophthalein, O, O'-di (tert-butoxycarbonyl) -3,3 ', 5,5'-tetrabromophenolsulfophthalein, O , O'-di (tert-butoxycarbonyl) -2,2'-dimethyl-3,3 ',
5,5'-tetrabromophenol sulfophthalein,
O, O'-di (tert-butoxycarbonyl) -3,3 '
-Dibromophenol sulfophthalein, O, O'-di (tert-butoxycarbonyl) -3,3'-dibromo-
5,5'-dimethylphenolsulfophthalein, O,
O'-di (tert-butoxycarbonyl) -2,2'-dimethyl-3,3'-dibromo-5,5'-diisopropylphenolsulfophthalein, O, O'-di (1,1
-Diethylhexyloxycarbonyl) phenolsulfophthalein, O- (tert-butoxycarbonyl)-
O'-methylphenol sulfophthalein, O, O'-
Di (1,1-dimethylpentyloxycarbonyl) -phenolsulfophthalein, O- (tert-butoxycarbonyl) phenolsulfophthalein, O, O'-di (1,1-diethylhexyloxycarbonyl) -3,
3'-dibromo-5,5'-dimethylphenolsulfophthalein, O- (tert-butoxycarbonyl) -O '
-Acetylphenol sulfophthalein, O- (tert-
Butoxycarbonyl) -O'-benzylcarbonylphenolsulfophthalein, O- (tert-butoxycarbonyl) -O'-phenylcarbonylphenolsulfophthalein, O- (tert-butoxycarbonyl) -O'-
(1,1-Dimethylpentyloxycarbonyl) phenolsulfophthalein, O- (tert-butoxycarbonyl) -O'-benzyloxycarbonylphenolsulfophthalein, O- (tert-butoxycarbonyl)-
O'-phenyloxycarbonylphenol sulfophthalein.

The following can be exemplified as [Chemical Formula 3]. O, O'-di (tert-butoxycarbonyl) indigo white, O, O'-di (tert-butoxycarbonyl) -5-bromoindigo white, O, O'-di (te
rt-butoxycarbonyl) -5,5′-dibromoindigo white, O, O′-di (tert-butoxycarbonyl) -5,5 ′, 7-tribromoindigo white,
O, O'-di (tert-butoxycarbonyl) -5,
5 ', 7,7'-tetrabromoindigo white, O,
O'-di (tert-butoxycarbonyl) -4,4 ',
5,5 ', 7,7'-hexabromoindigo white,
O, O'-di (tert-butoxycarbonyl) -5,
5 ', 7,7'-tetrachloroindigo white, O,
O'-di (tert-butoxycarbonyl) -4,4'-dichloroindigo white, O, O'-di (tert-butoxycarbonyl) -4,4 ', 5,5'-tetrachloroindigo white, O, O'-di (tert-butoxycarbonyl) -6,6'-dimethylindigo white, O,
O'-di (tert-butoxycarbonyl) -5,5'-difluoroindigo white, O, O'-di (tert-butoxycarbonyl) -N, N'-hexamethyleneindigo white, O, O'-di ( tert-butoxycarbonyl)
-N, N'-ethyleneindigo white, O, O'-di (tert-butoxycarbonyl) -N, N'-ethenyleneindigo white, O, O'-di (tert-butoxycarbonyl) -4,4 '-Dichloro-5,5'-dibromoindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-dimethylindigo white, O,
O'-di (tert-butoxycarbonyl) -7,7'-dimethylindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-dimethyl-7,7'-dichloroindigo white, O , O'-di (tert-butoxycarbonyl) -6,6'-diethylindigo white,
O, O'-di (tert-butoxycarbonyl) -7,7 '
-Didecyl indigo white, O, O'-di (tert-butoxycarbonyl) -6,6'-dimethoxyindigo white, O, O'-di (tert-butoxycarbonyl)-
6,6'-Dinonanoxyindigo white, O, O'-
Di (tert-butoxycarbonyl) -6,6'-di (ethylthio) indigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-dinitroindigo white, O, O'-di (tert -Butoxycarbonyl) -5,
5'-diaminoindigo white, O, O'-di (tert
-Butoxycarbonyl) -6,6'-di (N, N-dimethylamino) indigo white, O, O'-di (tert-
Butoxycarbonyl) -5,5'-di (N, N-dinonaamino) indigo white, O, O'-di (tert-butoxycarbonyl) -6,6'-dipyrrolidinoindigo white, O, O'-di (Tert-butoxycarbonyl)-
5,5'-di (N-phenylamino) indigo white, O, O'-di (tert-butoxycarbonyl) -N,
N'-dimethyl indigo white, O, O'-di (tert
-Butoxycarbonyl) -N, N'-diethylindigo white, O, O'-di (tert-butoxycarbonyl)
-N, N'-dioctyl indigo white, O, O'-
Di (tert-butoxycarbonyl) -5,5'-dibromo-N, N'-diethylindigo white, O, O'-di (tert-butoxycarbonyl) -N, N'-diacetylindigo white, O, O ' -Di (tert-butoxycarbonyl) -N, N'-dibenzoylindigo white,
O, O'-di (tert-butoxycarbonyl) -N, N '
-Givarelyl indigo white, O, O ', N, N'-
Tetra (tert-butoxycarbonyl) indigo white, O, O ′, N, N′-tetra (tert-butoxycarbonyl) -4,4′-dichloroindigo white, O,
O'-di (1,1-dimethylpropoxycarbonyl) indigo white, O, O'-di (1,1-diethylbutoxycarbonyl) indigo white, O, O'-di (1,1-diethylbutoxycarbonyl)- 6,6'-
Dibromoindigo white, O, O'-di (1,1-diethylbutoxycarbonyl) -N, N'-dimethylindigo white, O- (tert-butoxycarbonyl)-
O '-(1,1-diethylbutoxycarbonyl) indigo white, 2- [3'-(tert-butoxycarbonyloxy) benzothiophen-2'-yl] -3- (tert
-Butoxycarbonyloxy) indole, 2- [3 '
-(Tert-butoxycarbonyloxy) -5'-bromobenzothiophene-2'-yl] -3- (tert-butoxycarbonyloxy) -5-bromoindole, O,
O'-di (tert-butoxycarbonyl) thioindigo white, O, O'-di (tert-butoxycarbonyl)-
5,5'-dichlorothioindigo white, O, O'-
Di (tert-butoxycarbonyl) -6,6'-dichlorothioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-dibromothioindigo white, O, O'-di (tert- Butoxycarbonyl) -5,
5'-diisopropylthioindigo white, O, O '
-Di (tert-butoxycarbonyl) -7,7'-diisopropylthioindigo white, O, O'-di (tert-
Butoxycarbonyl) -4,4'-dimethyl-6,6 '
-Dichlorothioindigo white, O, O'-di (tert
-Butoxycarbonyl) -5,5 ', 7,7'-tetramethylthioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-diaminothioindigo white, O, O'-di ( tert-butoxycarbonyl)
-6,6'-di (N, N-dimethylamino) thioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-di (N, N-dinonylamino) thioindigo white, O , O'-di (tert-butoxycarbonyl) -5,5'-dimethoxythioindigo white,
O, O'-di (tert-butoxycarbonyl) -6,6 '
-Diethoxythioindigo white, O, O'-di (te
rt-Butoxycarbonyl) -6,6'-dioctoxythioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-di-tert-butylthioindigo white, O, O'- Di (tert-butoxycarbonyl)
-5,5'-Dichloro-7,7'-dimethylthioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-di (ethylthio) thioindigo white, O, O'-di (Tert-butoxycarbonyl) -6,
6'-di (ethylthio) thioindigo white, O,
O'-di (tert-butoxycarbonyl) -4,4 ',
7,7'-Tetramethyl-5,5'-dichlorothioindigo white, O, O'-di (tert-butoxycarbonyl) -5,5'-dibromo-6,6'-diethoxythioindigo white, O , O'-di (tert-butoxycarbonyl) -4,5-, 4 ', 5'-dibenzothioindigo white, O, O'-di (tert-butoxycarbonyl) -5,6-, 5', 6 ′ -Dibenzothioindigo white, O, O′-di (1,1-dimethylpropoxycarbonyl) thioindigo white, O, O′-di (1,
1-dimethylbutoxycarbonyl) thioindigo white, O, O'-di (1,1-diethylpropoxycarbonyl) thioindigo white, O, O'-di (1,1-
Diethylpropoxycarbonyl) -5,5'-dichlorothioindigo white, O- (tert-butoxycarbonyl) -O '-(1,1-diethylbutoxycarbonyl)
Thioindigo white etc.

Of course, the compounds are not limited to these compounds, and if necessary, two or more kinds of dye precursors may be used in combination.

In the present invention, a coating liquid containing an organic solvent is prepared, and a thermosensitive recording layer is formed by coating or printing. The organic solvent used is not particularly limited, but alcohols, ketones, esters, aromatic hydrocarbons, halogenated hydrocarbons, aliphatic hydrocarbons, naphthene-based hydrocarbons and the like are more excellent in water resistance. It is preferably used because a heat-sensitive layer can be obtained.

Specific examples of the organic solvent include alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, ethylene glycol, and glycerin, ketones such as acetone, butanone, pentanone, methylisopropylketone, cyclohexanone, and the like. Esters such as ethyl acetate and butyl acetate, aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene, dichlorobenzene, cumene and cymene, aliphatic hydrocarbons such as pentane, heptane and octane, cyclohexane, methylcyclohexane, ethylcyclohexane , Naphthenic hydrocarbons such as cyclopentane, linseed oil, rosin oil, petroleum ether, ligroin and the like, but of course not limited to these, it is also possible to use two or more solvents in combination. . As a medium for the coating liquid, water may be contained as long as the effect is not impaired. For example, printing can be performed using a medium containing alcohols and water.

The organic solvent-soluble resin used in the heat-sensitive recording layer is preferably an organic solvent-soluble resin which is insoluble in water. Particularly, a thermoplastic resin is preferably used, and a thermoplastic resin soluble in an organic solvent as described above is more preferably used. Examples of such a thermoplastic resin include the following. Poly (methyl methacrylate), poly (ethyl methacrylate), poly (ethyl acrylate), poly (butyl acrylate), polystyrene, acrylic ester / styrene copolymer, polyester resin, poly α-methyl styrene, AB
S resin, coumarone resin, nitrocellulose, ethylene
Examples thereof include vinyl acetate copolymer, but of course, the resins are not limited to these resins, and two or more kinds of resins can be used in combination.

The amount of the adhesive used is not particularly limited, but when it is contained in the recording layer coating liquid, it is 1 to 90% by weight, preferably 5% based on the total solid amount of the recording layer coating liquid. ~
It is desirable to adjust in the range of 60% by weight. By using the organic solvent-soluble resin as described above, the adhesion of the coating layer to the support or the recording layer becomes smooth, and in combination with the use of a specific dye precursor, the whiteness is high, It is possible to obtain a heat-sensitive recording material which is excellent in water resistance and is excellent in storability and color development in various solvents.

A protective layer may be formed on the heat-sensitive recording layer. The protective layer contains various resins and the like, and the above-mentioned organic solvent-soluble resins and the like can be exemplified.
When a resin is used in the protective layer coating liquid, it is desirable to adjust the amount in the range of 5 to 95% by weight, preferably 20 to 95% by weight based on the total solid content of the protective layer coating liquid. The protective layer may contain various pigments and auxiliaries.

In the present invention, as the color former constituting the heat-sensitive recording layer together with the specific dye precursor, various organic acid substances such as aromatic carboxylic acid derivatives and phenol derivatives, inorganic acid substances such as acid clay and the like are used. Acidic substances can be used. Examples of such acidic substances include the following. Benzoic acid, 4-tert-butylbenzoic acid, 4
-Chlorobenzoic acid, 4-nitrobenzoic acid, phthalic acid, gallic acid, salicylic acid, 3-isopropylsalicylic acid, 3
-Phenylsalicylic acid, 3-cyclohexylsalicylic acid, 3,5-di-tert-butylsalicylic acid, 3-methyl-5-benzylsalicylic acid, 4-pentyloxysalicylic acid, 4- (3-p-tolylsulfonylpropoxy) salicylic acid, 4- (2-p-Methoxy-phenoxyethoxy) salicylic acid, 5- [p- (2-p-methoxyphenoxyethoxy) cumyl] salicylic acid, 3-phenyl-5
-(Α, α-Dimethylbenzyl) salicylic acid, 3,5-
Aromatic carboxylic acid derivatives such as di- (α-methylbenzyl) salicylic acid and 2-hydroxy-1-benzyl-3-naphthoic acid; 4,4′-isopropylidenediphenol (bisphenol A), 4,4′-isopropylidene Liden bis (2-chlorophenol), 4,4'-isopropylidene bis (2,6-dichlorophenol), 4,4'-
Isopropylidene bis (2,6-dibromophenol), 4,4'-isopropylidene bis (2-methylphenol), 4,4'-isopropylidene bis (2,6)
-Dimethylphenol), 4,4'-isopropylidenebis (2-tert-butylphenol), 4,4'-sec
-Butylidene diphenol, 2,2'-bis (4-hydroxyphenyl) -4-methylpentane, 4,4'-cyclohexylidenebisphenol, 4,4'-cyclohexylidenebis (2-methylphenol), 4 −tert−
Butylphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, methyl-4-hydroxybenzoate, benzyl-
4-hydroxybenzoate, 2,2'-thiobis (4,6-dichlorophenol), 4-tert-octylcatechol, 2,2'-methylenebis (4-chlorophenol), 2,2'-methylenebis (4-methyl) -6-
tert-butylphenol), 2,2'-dihydroxydiphenyl, methyl-bis (4-hydroxyphenyl)
Acetate, ethyl-bis (4-hydroxyphenyl)
Acetate, benzyl-bis (4-hydroxyphenyl) acetate, 4,4 '-(p-phenylenediisopropylidene) diphenol, 4,4'-(m-phenylenediisopropylidene) diphenol, 4-hydroxydiphenylsulfone , 4,4'-dihydroxydiphenyl sulfone, 2,4'-dihydroxydiphenyl sulfone, 4-hydroxy-4'-methyl-diphenyl sulfone, 4-hydroxy-4'-isopropoxydiphenyl sulfone, 4-hydroxy-3 ', 4'-tetramethylene diphenyl sulfone, 3,3'-diallyl-4,4 '
-Phenolic compounds such as dihydroxydiphenyl sulfone; p-phenylphenol-formalin resin, p-
Organic acidic substances such as phenolic resins such as butylphenol-acetylene resin; and further these organic acidic substances and, for example, zinc, magnesium, aluminum, calcium,
Salts with polyvalent metals such as titanium, manganese, tin and nickel; metal complex compounds such as antipyrine complexes of zinc thiocyanate. Of course, it is not limited to these, and it is also possible to use two or more kinds together if necessary.

The ratio of the specific dye precursor and the acidic substance used in the heat-sensitive recording layer is not particularly limited, but generally 0.1 to 5 per 1 part by weight of the dye precursor.
It is desirable to use 0 parts by weight, preferably 1 to 20 parts by weight of the acidic substance.

The present invention uses the above-mentioned specific dye precursor as the dye precursor, but if necessary, a known dye precursor may be used within a range that does not impair the desired effects of the present invention. It can also be used together. Examples of such known dye precursors include the following. 3,3-bis (p-
Dimethylaminophenyl) -6-dimethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) phthalide, 3- (4-dimethylaminophenyl) -3- (4
-Diethylamino-2-methylphenyl) -6-dimethylaminophthalide, 3- (p-dimethylaminophenyl) -3- (1,2-dimethylindol-3-yl)
Phthalide, 3- (p-dimethylaminophenyl) -3-
(2-Methylindol-3-yl) phthalide, 3,3
-Bis (1,2-dimethylindol-3-yl) -5
-Dimethylaminophthalide, 3,3-bis (1,2-dimethylindol-3-yl) -6-dimethylaminophthalide, 3,3-bis (9-ethylcarbazole-3-
Yl) -6-dimethylaminophthalide, 3,3-bis (2-phenylindol-3-yl) -6-dimethylaminophthalide, 3- (p-dimethylaminophenyl)
-3- (1-Methylpyrrol-3-yl) -6-dimethylaminophthalide, 3- (p-dibenzylaminophenyl) -3- (1,2-dimethylindol-3-yl)
-7-azaphthalide, 3- (4-diethylamino-2-
Ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -7-azaphthalide, 3,3-bis (1-ethyl-2-methylindol-3-yl) phthalide, N-butyl- Triarylmethane compounds such as 3- {bis [4- (N-methylanilino) phenyl] methyl} carbazole, 4,4′-bis (dimethylamino) benzhydrylbenzyl ether, N-halophenyl-leuco auramine, N -Diphenylmethane compounds such as 2,4,5-trichlorophenyl leuco auramine and 4,4'-bis (dimethylamino) benzhydryl-p-toluenesulfinic acid ester, 3,7-bis (diethylamino) -10-benzoylpheno Oxazine,
Thiazine-based compounds such as benzoyl leuco methylene blue and p-nitrobenzoyl leuco methylene blue, 3-methylspirodinaphthopyran, 3-ethylspirodinaphthopyran, 3-phenylspirodinaphthopyran, 3-benzylspirodinaphthopyran, 3- Methyl naphtho (6'-
Spiro compounds such as (methoxybenzo) spiropyran, 3-propylspirodibenzopyran, di-β-naphthospiropyran, and 3-methyl-di-β-naphthospiropyran,
Rhodamine-B-anilinolactam, Rhodamine (p-
Lactam compounds such as nitroanilino) lactam, rhodamine (o-chloroanilino) lactam, 3-diethylamino-6-methylfluorane, 3-dimethylamino-
7-methoxyfluorane, 3-diethylamino-6-methoxyfluorane, 3-diethylamino-7-methoxyfluorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-6,7-dimethylfluorane, 3- (N-ethyl-p-toluidino) -7-methylfluorane, 3-diethylamino-7- (N-acetyl-N-methylamino) fluorane, 3- Diethylamino-7- (N-methylamino) fluorane, 3-diethylamino-7-dibenzylaminofluorane, 3-diethylamino-7- (N-methyl-N-benzylamino)
Fluorane, 3-diethylamino-7- (N-β-chloroethyl-N-methylamino) fluorane, 3-diethylamino-7-diethylaminofluorane, 4-benzylamino-8-diethylaminobenzo [a] fluorane, 3- [4 -(4-Dimethylaminoanilino) anilino] -7-chloro-6-methylfluorane, 8- [4-
(4-Dimethylaminoanilino) anilino] benzo [a] fluorane, 3- (N-ethyl-p-toluidino) -6-methyl-7-phenylaminofluorane, 3
-(N-ethyl-p-toluidino) -6-methyl-7-
(P-Toluidino) fluorane, 3-diethylamino-
6-methyl-7-phenylaminofluorane, 3-dibutylamino-6-methyl-7-phenylaminofluorane, 3-dipentylamino-6-methyl-7-phenylaminofluorane, 3-diethylamino-7- ( 2-carbomethoxy-phenylamino) fluorane, 3- (N
-Ethyl-N-isoamylamino) -6-methyl-7-
Phenylaminofluorane, 3- (N-cyclohexyl-N-methylamino) -6-methyl-7-phenylaminofluorane, 3-pyrrolidino-6-methyl-7-phenylaminofluorane, 3-piperidino-6- Methyl-
7-phenylaminofluorane, 3-diethylamino-
6-methyl-7-xylidinofluorane, 3-diethylamino-7- (o-chlorophenylamino) fluorane, 3-dibutylamino-7- (o-chlorophenylamino) fluorane, 3- (N-ethyl-N-isoamyl Amino) -7- (o-chlorophenylamino) fluorane, 3- (N-methyl-N-propylamino) -6-methyl-7-phenylaminofluorane, 3-pyrrolidino-6-methyl-7-p-butyl Phenylaminofluorane, 3- (N-ethyl-N-isobutylamino) -6-
Methyl-7-phenylaminofluorane, 3-pyrrolidino-6-methyl-7-pn-butylphenylaminofluorane, 3- (N-methyl-Nn-hexylamino) -6-methyl-7- Phenylaminofluorane, 3
-(N-Ethyl-N-n-hexylamino) -6-methyl-7-phenylaminofluorane, 3- (N-ethyl-N-cyclopentylamino) -6-methyl-7-phenylaminofluorane, 3 -[N- (3-Ethoxypropyl) -N-methylamino] -6-methyl-7-phenylaminofluorane, 3- [N-ethyl-N- (3-ethoxypropyl) amino] -6-methyl- 7-phenylaminofluorane, 3-diethylamino-7- [m-
(Trifluoromethyl) phenylamino] fluorane,
3-diethylamino-7- (o-fluorophenylamino) fluorane, 3-dibutylamino-7- (o-fluorophenylamino) fluorane, 3-diethylamino-6-chloro-7-phenylaminofluorane, 3-
(N-ethyl-Np-tolylamino) -7-methylfluorane, 3- (N-ethyl-N-tetrahydrofurfurylamino) -6-methyl-7-anilinofluorane,
3- (N-cyclopentyl-N-ethylamino) -6-
Methyl-7-anilinofluorane, 3- (N-ethyl-
N-p-tolylamino) -6-methyl-7-anilinofluorane, 2,2'-bis {4- [6 '-(N-cyclohexyl-N-methylamino) -3'-methylspiro [phthalide-3] , 9′-xanthene] -2′-ylamino] phenyl} propane and the like, 3,
6-bis (dimethylamino) fluorene-9-spiro-
3 '-(6'-Dimethylamino) phthalide, 3-diethylamino-6- (N-allyl-N-methylaminofluorene-9-spiro-3'-(6'-dimethylamino) phthalide, 3,6-bis (Dimethylamino) -spiro [fluorene-9,6'-6'H-chromeno (4,3-b)
Indole], 3,6-bis (dimethylamino) -3 '
-Methyl-spiro [fluorene-9,6'-6'H-chromeno (4,3-b) indole], 3,6-bis (diethylamino) -3'-methyl-spiro [fluorene-
Fluorene compounds such as 9,6′-6′H-chromeno (4,3-b) indole] and the like.

In the present invention, various heat fusible substances may be used as a recording sensitivity improving agent in order to obtain higher speed recording property. Examples of such heat-fusible substances include caproic acid amide, capric acid amide, palmitic acid amide, stearic acid amide, oleic acid amide, erucic acid amide, linoleic acid amide, linolenic acid amide,
N-methylstearic acid amide, stearic acid anilide, N-methyloleic acid amide, benzanilide, linoleic acid anilide, N-ethylcapric acid amide, N-
Butyllauric acid amide, N-octadecylacetamide, N-oleinacetamide, N-oleylbenzamide, N-stearylcyclohexylamide, polyethylene glycol, 1-benzyloxynaphthalene, 2-
Benzyloxynaphthalene, 1-hydroxynaphthoic acid phenyl ester, 1,2-diphenoxyethane, 1,
4-diphenoxybutane, 1,2-bis (3-methylphenoxy) ethane, 1,2-bis (4-methoxyphenoxy) ethane, 1-phenoxy-2- (4-chlorophenoxy) ethane, 1-phenoxy- 2- (4-methoxyphenoxy) ethane, 1- (2-methylphenoxy)-
2- (4-methoxyphenoxy) ethane, terephthalic acid dibenzyl ester, oxalic acid dibenzyl ester, oxalic acid di-p-methylbenzyl ester, p-benzyloxybenzoic acid benzyl ester, p-benzylbiphenyl, 1,5- Bis (p-methoxyphenoxy) -3-
Oxa-pentane, 1,4-bis (2-vinyloxyethoxy) benzene, p-biphenyl-p-tolyl-ether, benzyl-p-methylthiophenyl ether, 4
-Chlorobenzyl-4-ethoxyphenyl-ether,
Examples include compounds such as 1,2-bis (3,4-dimethylphenyl) ethane.

Further, various auxiliaries can be added to the recording layer and the protective layer, for example, a dispersant, an ultraviolet absorber such as a triazole type, an antifoaming agent, a fluorescent dye, a coloring dye and the like. Can be mentioned. In addition, stearic acid ester wax, polyethylene wax, carnauba wax, microcrystalline wax, carboxy-modified paraffin wax, zinc stearate, calcium stearate, etc. are added to prevent the thermal recording material from sticking due to contact with recording equipment or recording head. You can also do it.

In addition, kaolin, clay, talc, calcium carbonate,
Magnesium carbonate, calcined clay, titanium oxide, diatomaceous earth,
Pigments such as fine particulate anhydrous silica and activated clay can also be added. The thermal recording material of the present invention, in a medium containing an organic solvent, a specific dye precursor, a coating solution in which a colorant is uniformly dispersed or dissolved, for example, a thermoplastic resin is dissolved as an adhesive,
It can be obtained by applying it on a suitable support such as paper, plastic film, synthetic paper, or woven fabric sheet molding, and optionally forming a protective layer. The heat-sensitive recording layer is formed by coating or printing, and various types of coaters and printing machines are used.

It is also possible to separately coat the dispersion or solution of the dye precursor and the dispersion or solution of the acidic substance separately. The coating amount of the coating liquid for forming the recording layer on the support is not particularly limited, and is usually ² to 12 g / m ^{2 as} a dry weight.
It is adjusted in the range of about 3 to 10 g / m ² . Furthermore, when a protective layer is provided, the coating amount is not particularly limited, and usually 0.5 to 20 g / dry weight.
m ² approximately, is adjusted preferably in the range of about 1 to 10 g / m ^2.

Incidentally, it is of course possible to provide an antistatic layer or a protective layer on the back surface of the support, or to provide an undercoat layer on the support, and to manufacture a heat-sensitive recording material by subjecting the back surface of the support to an adhesive treatment. Various known techniques in the field can be added.

[0038]

The present invention will be described in more detail by way of the following examples, but the present invention is not limited to these examples. Unless otherwise specified, parts in the examples represent parts by weight or% by weight.

Example 1 Solution A: 3,6-di (tert-butoxycarboxy) fluorane 15 parts, styrene-ethyl acrylate copolymer
It consists of 10 parts, 40 parts of 1,2-bis (3-methylphenoxy) ethane and 75 parts of toluene. Solution B: Consists of 15 parts of a zinc salt of 3,5-di (α-methylbenzyl) salicylic acid, 10 parts of a styrene-ethyl acrylate copolymer, and 75 parts of toluene.

After the above liquids A and B were separately pulverized and dispersed in a sand mill for 2 hours, these dispersions were liquid A: liquid B =
A coating solution sufficiently mixed at a ratio of 1: 3 was applied to a base paper of 50 g / m ^{2 so} that the dry weight was 6.0 g / m ^2, and dried to form a heat-sensitive recording layer. Then, as a protective layer, the following liquid C was applied on the thermosensitive recording layer so as to be 2 g / m ² and dried to obtain a thermosensitive recording material. Solution C: Consists of 1 part zinc stearate, 9 parts polymethylmethacrylate, 5 parts calcium carbonate and 90 parts toluene.

Examples 2 to 15 In the same manner as in Example 1 except that the following compounds were used in place of 3,6-di (tert-butoxycarboxy) fluorane in the liquid A of Example 1, 14 kinds of thermal recordings were carried out. Got the body Example 2: 3- (tert-butoxycarboxy) -6-
Methoxyfluorane Example 3: 3- (tert-butoxycarboxy) -6-
Dimethylaminofluorane Example 4: 3,6-di (tert-butoxycarboxy)
-2,4,5,7-Tetrabromofluorane Example 5: 3,6-di (tert-butoxycarboxy)
-1,8-Dimethyl-3 ', 4', 5 ', 6'-tetrachlorofluorane Example 6: 3,6-di (1,1-dimethylpropoxycarboxy) fluorane Example 7: O, O' -Di (tert-butoxycarbonyl) phenol sulfophthalein Example 8: O, O'-di (tert-butoxycarbonyl) -2,2'-dimethyl-3,3'-dibromo-5,5.
5'-Diisopropylphenol sulfophthalein Example 9: O, O'-di (1,1-dimethylbutoxycarbonyl) phenol sulfophthalein Example 10: O, O'-di (tert-butoxycarbonyl) indigo white Example Example 11: O, O'-di (tert-butoxycarbonyl) -6,6'-dibromoindigo white Example 12: O, O'-di (tert-butoxycarbonyl) -N, N'-dimethylindigo white Example 13: O, O'-di (tert-butoxycarbonyl) thioindigo white Example 14: O, O'-di (tert-butoxycarbonyl) -5,5'-dichloro-7,7'-dimethylthioindigo White Example 15: O, O'-di (1,1-dimethylpropoxycarbonyl) indigo white

Example 16 A thermosensitive recording medium was prepared in the same manner as in Example 1 except that ethylene-vinyl acetate copolymer was used in place of the styrene-ethyl acrylate copolymer in the liquids A and B of Example 1. Obtained.

Example 17 A thermosensitive recording medium was obtained in the same manner as in Example 1 except that the following liquid D was used in place of the liquid B and the liquid C was not used. Liquid D: 3,5-di (α-methylbenzyl) salicylic acid zinc salt 15 parts, styrene-ethyl acrylate copolymer 10 parts, zinc stearate 5 parts, calcium carbonate 5
And toluene 75 parts.

Examples 18 to 22 Five kinds of thermal recording materials were obtained in the same manner as in Example 1 except that the following solvents were used in place of toluene in the liquids A and B of Example 1. Example 18: Xylene Example 19: Toluene: methylcyclohexane 3: 1
Example 20: Ethyl acetate Example 21: Isopropanol Example 22: Butanone

Example 23 A thermal recording material was obtained in the same manner as in Example 1 except that calcium carbonate was not used in the liquid C of Example 1.

Examples 24 to 25 In the same manner as in Example 1, except that the following compound was used in place of the zinc salt of 3,5-di (α-methylbenzyl) salicylic acid in the solution A of Example 1, 2 Two kinds of thermal recording materials were obtained. Example 24: 4,4'-Isopropylidene diphenol Example 25: 3,5-di (α-methylbenzyl) salicylic acid

Example 26 A thermosensitive recording medium was obtained in the same manner as in Example 1 except that a polyethylene film was used as the support instead of the base paper.

Comparative Examples 1 to 3 Three kinds of heat-sensitive recording were conducted in the same manner as in Example 1 except that the following compounds were used in place of 3,6-di (tert-butoxycarboxy) fluorane in the liquid A of Example 1. Got the body Comparative Example 1: 3,6-Dimethoxyfluorane Comparative Example 2: 3-Dibutylamino-6-methyl-7-anilino-fluorane Comparative Example 3: Crystal Violet Lactone

Comparative Example 4 The same procedure as in Example 1 was repeated except that the following solution G was used instead of the solution A, the solution H was used instead of the solution B, and the solution F was used instead of the solution C. I got a record. Solution F: zinc stearate 1 part, polyvinyl alcohol 20% aqueous solution 45 parts, calcium carbonate 5 parts, water 2
It consists of 4 parts. Solution G: 3,6-di (tert-butoxycarboxy) fluorane 15 parts, 1,2-bis (3-methylphenoxy)
40 parts of ethane, 25% aqueous solution of methyl cellulose 25
And 40 parts of water. Solution H: 3,5-di (α-methylbenzyl) salicylic acid zinc salt 15 parts, methylcellulose 25% aqueous solution 25
And 40 parts of water.

Comparative Example 5 The same procedure as in Example 1 was repeated except that the following solution I was used instead of solution A, the following solution J was used instead of solution B, and solution F was used instead of solution C. I got a record. Solution I: 3,6-di (tert-butoxycarboxy) fluorane 15 parts, 1,2-bis (3-methylphenoxy)
40 parts of ethane, 25% aqueous solution of methyl cellulose 25
And 40 parts of water. Solution J: 4,4'-isopropylidenediphenol 15
Part, 25% aqueous solution of methyl cellulose 25 parts, water 40
Consists of parts.

The whiteness of each heat-sensitive recording material thus obtained was measured with a Hunter whiteness meter and is shown in Table 1. Next, a thermal facsimile (Hitachi HIFAX-700, manufactured by Hitachi Ltd.) was used for recording, and the color density thereof is shown in Table 1.
Further, in order to evaluate the chemical resistance, when a vinyl chloride film was placed on the color developing surface of the above recording medium and left at 40 ° C. for 200 hours (plasticizer resistance), when the color developing surface was coated with ethanol (ethanol resistance) The degree of fog on the blank sheet and the degree of fading of the recorded image were evaluated for each of the properties), and the results are shown in Table 1. The evaluation criteria are as follows.

"Evaluation Criteria" A: Excellent. ◯: Excellent. Δ: Slightly inferior X: Inferior

Further, in order to evaluate the water resistance, water was applied to the coloring surface and the surface was rubbed by hand to observe the elution state of the applied layer with respect to water. The evaluation criteria are as follows. "Evaluation criteria" A: No elution occurs. ◯: It elutes slightly, but there is no problem in practical use. X: Elution is quite strong.

[0054]

[Table 1]

[0055]

As is clear from the results shown in Table 1, the present invention is a method for producing a heat-sensitive recording material having high whiteness, excellent chemical resistance, plasticity resistance and water resistance, and excellent color development. It was

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 2, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

[0021]

The following can be exemplified as [Chemical Formula 1]. 3,6-di (tert-butoxycarboxy) fluorane, 3,6-di (1,1-dimethylpropoxycarboxy) fluorane, 3,6-di (1-methyl-1-ethylbutoxycarboxy) fluorane, 3,6 -Di (tert-
Butoxycarboxy) -4,5-dimethylfluorane,
3,6-di (tert-butoxycarboxy) -1,8-dimethylfluorane, 3,6-di (tert-butoxycarboxy) -2,7-diethylfluorane, 3,6-di (te
rt-Butoxycarboxy) -1,5-diethylfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -2,7-diethylfluorane, 3,6-di (tert.
-Butoxycarboxy) -4,5-dinitrofluorane, 3,6-di (tert-butoxycarboxy) -2,7
-Didecylfluorane, 3,6-di (tert-butoxycarboxy) -2-dodecyl-8-methylfluorane,
3,6-di (tert-butoxycarboxy) -6'-butoxyfluorane, 3,6-di (tert-butoxycarboxy) -4'-methoxyfluorane, 3,6-di (tert-
Butoxycarboxy) -4'-decaoxyfluorane,
3- (tert-butoxycarboxy) -6-methoxyfluorane, 3- (tert-butoxycarboxy) -7-methoxyfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -6'-butoxyfluor Oran, 3-
(Tert-Butoxycarboxy) -6-ethoxy-2,7
-Dioctylfluorane, 3- (1,1-dipropylbutoxycarboxy) -2,4,5,7-tetrachlorofluorane, 3,6-di (tert-butoxycarboxy)-
2,4,5,7-Tetrachlorofluorane, 3,6-di (tert-butoxycarboxy) -2,4,5,7-tetrabromofluorane, 3,6-di (tert-butoxycarboxy)- 2,4,5,7-tetraiodofluorane,
3,6-di (tert-butoxycarboxy) -1,8-dimethyl-3 ', 4', 5 ', 6'-tetrachlorofluorane, 3,6-di (tert-butoxycarboxy)-
3 ', 4', 5 ', 6'-tetrabromofluorane,
3,6-di (1,1-dimethylpropoxycarboxy)
-2,7-dibromofluorane, 3,6-di (1,1-
Dimethylpropoxycarboxy) -4,5-dinitrofluorane, 3,6-di (1,1-diethylhexaoxycarboxy) -3 ', 4', 5 ', 6'-tetrachlorofluorane, 3,6- Di (tert-butoxycarboxy)
-2,7-dibromofluorane, 3- (1,1-dipropylbutoxycarboxy) -6-methoxyfluorane,
3- (tert-butoxycarboxy) -6-ethoxy-
2,7-dibenzylfluorane, 3- (tert-butoxycarboxy) -6-methoxycarboxyfluorane, 3
-(Tert-butoxycarboxy) -7-methoxycarboxyfluorane, 3- (tert-butoxycarboxy)-
6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminofluorane,
3- (tert-butoxycarboxy) -6-diethylaminofluorane, 3- (tert-butoxycarboxy) -7
-Diethylaminofluorane, 3- (tert-butoxycarboxy) -6-dibutylaminofluorane, 3- (te
rt-Butoxycarboxy) -6-didodecylaminofluorane, 3- (tert-butoxycarboxy) -6-piperidinofluorane, 3- (tert-butoxycarboxy)
-6- (N-Ethyl-N-isopentyl) aminofluorane, 3- (tert-butoxycarboxy) -6- (N-
Cyclohexyl-N-methyl) aminofluorane, 3-
(Tert-butoxycarboxy) -6-phenoxycarboxyfluorane, 3- (tert-butoxycarboxy)-
6-benzyloxycarboxyfluorane, 3- (1,
1-dimethylhexaoxycarboxy) -6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-butylcarboxyfluorane, 3- (tert
-Butoxycarboxy) -6-phenylcarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminocarboxyfluorane. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] May 20, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

The following can be exemplified as [Chemical Formula 1]. 3,6-di (tert-butoxycarboxy) fluorane, 3,6-di (1,1-dimethylpropoxycarboxy) fluorane, 3,6-di (1-methyl-1-ethylbutoxycarboxy) fluorane, 3,6 -Di (tert-
Butoxycarboxy) -4,5-dimethylfluorane,
3,6-di (tert-butoxycarboxy) -1,8-dimethylfluorane, 3,6-di (tert-butoxycarboxy) -2,7-diethylfluorane, 3,6-di (te
rt-Butoxycarboxy) -1,5-diethylfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -2,7-diethylfluorane, 3,6-di (tert.
-Butoxycarboxy) -4,5-dinitrofluorane, 3,6-di (tert-butoxycarboxy) -2,7
-Didecylfluorane, 3,6-di (tert-butoxycarboxy) -2-dodecyl-8-methylfluorane,
3,6-di (tert-butoxycarboxy) -6'-butoxyfluorane, 3,6-di (tert-butoxycarboxy) -4'-methoxyfluorane, 3,6-di (tert-
Butoxycarboxy) -4'-decaoxyfluorane,
3- (tert-butoxycarboxy) -6-methoxyfluorane, 3- (tert-butoxycarboxy) -7-methoxyfluorane, 3,6-di (1,1-dimethylpropoxycarboxy) -6'-butoxyfluor Oran, 3-
(Tert-Butoxycarboxy) -6-ethoxy-2,7
-Dioctylfluorane, 3- (1,1-dipropylbutoxycarboxy) -2,4,5,7-tetrachlorofluorane, 3,6-di (tert-butoxycarboxy)-
2,4,5,7-Tetrachlorofluorane, 3,6-di (tert-butoxycarboxy) -2,4,5,7-tetrabromofluorane, 3,6-di (tert-butoxycarboxy)- 2,4,5,7-tetraiodofluorane,
3,6-di (tert-butoxycarboxy) -1,8-dimethyl-3 ', 4', 5 ', 6'-tetrachlorofluorane, 3,6-di (tert-butoxycarboxy)-
3 ', 4', 5 ', 6'-tetrabromofluorane,
3,6-di (1,1-dimethylpropoxycarboxy)
-2,7-dibromofluorane, 3,6-di (1,1-
Dimethylpropoxycarboxy) -4,5-dinitrofluorane, 3,6-di (1,1-diethylhexaoxycarboxy) -3 ', 4', 5 ', 6'-tetrachlorofluorane, 3,6- Di (tert-butoxycarboxy)
-2,7-dibromofluorane, 3- (1,1-dipropylbutoxycarboxy) -6-methoxyfluorane,
3- (tert-butoxycarboxy) -6-ethoxy-
2,7-dibenzylfluorane, 3- (tert-butoxycarboxy) -6-methoxycarboxyfluorane, 3
-(Tert-butoxycarboxy) -7-methoxycarboxyfluorane, 3- (tert-butoxycarboxy)-
6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminofluorane,
3- (tert-butoxycarboxy) -6-diethylaminofluorane, 3- (tert-butoxycarboxy) -7
-Diethylaminofluorane, 3- (tert-butoxycarboxy) -6-dibutylaminofluorane, 3- (te
rt-Butoxycarboxy) -6-didodecylaminofluorane, 3- (tert-butoxycarboxy) -6-piperidinofluorane, 3- (tert-butoxycarboxy)
-6- (N-Ethyl-N-isopentyl) aminofluorane, 3- (tert-butoxycarboxy) -6- (N-
Cyclohexyl-N-methyl) aminofluorane, 3-
(Tert-butoxycarboxy) -6-phenoxycarboxyfluorane, 3- (tert-butoxycarboxy)-
6-benzyloxycarboxyfluorane, 3- (1,
1-dimethylhexaoxycarboxy) -6-decaoxycarboxyfluorane, 3- (tert-butoxycarboxy) -6-butylcarboxyfluorane, 3- (tert
-Butoxycarboxy) -6-phenylcarboxyfluorane, 3- (tert-butoxycarboxy) -6-dimethylaminocarboxyfluorane.

Claims (4)

[Claims] 1. A [Chemical formula 1], a [Chemical formula 2], and a [Chemical formula]
3] at least one dye precursor selected from the group
Coloring agent capable of coloring the dye precursor, organic solvent-soluble resin,
And thermal recording for applying or printing a coating liquid containing an organic solvent
Recording method. [Chemical 1][In the formula, R_aIs C_Four~ C₁₂Represents a tertiary alkyl group of R
₁~ R₁₁Are hydrogen atom, halogen atom, C₁~ C
₁₂Alkyl group of C₁~ C₁₂Alkoxyl group, hydroxy
Group, nitro group, -N (R₁₂) (R₁₃), -O (CO) OR
₁₄, Or -O (CO) R₁₅Indicates. However, R₁₂, R₁₃Is
Hydrogen atom; C₁~ C₁₂Alkyl group of C_Four~ C
₁₂Cycloalkyl group; halogen atom, C₁~ C₆A
Rukiru group, C₁ ~ C₆Substituted with the alkoxyl group of
Good aralkyl group; halogen atom, C₁~ C₆The al
Kill group, C₁~ C₆May be substituted with an alkoxyl group
Shows an aryl group, R₁₂And R₁₃Is an adjacent nitrogen atom
Pyrrolidino group, piperidino group or hexamethylene
An imino group may be formed. Also, R₁₄Is C₁~ C₁₂of
Alkyl group; benzyl group; halogen atom, C₁~ C₆of
Alkyl group, C₁~ C₆Substituted with an alkoxyl group of
Also represents an aryl group, R₁₅Is C₁~ C₁₂The alkyl
Group; benzyl group; halogen atom, C₁~ C₆The alkyl
Base, C₁~ C₆Which may be substituted with an alkoxyl group of
Reel base, -N (R₁₆) (R₁₇) Is shown. Incidentally, R₁₆, R₁₇
Are hydrogen atoms; C₁~ C₁₂Alkyl group of C_Four~
C₁₂Cycloalkyl group; halogen atom, C₁~ C₆of
Alkyl group, C₁~ C₆Substituted with an alkoxyl group of
Good aralkyl group; halogen atom, C₁~ C₆A
Rukiru group, C₁~ C₆Substituted with the alkoxyl group of
Shows a good aryl group, but R ₁₆And R₁₇Is the adjacent nitrogen source
With pyrrolidino group, piperidino group or hexamethy
It may also form a renimino group. ] [Chemical 2][In the formula, R_bIs C_Four~ C₁₂Represents a tertiary alkyl group of R
₁₈~ R₃₀Are hydrogen atom, halogen atom, C₁~ C
₁₂Alkyl group of C₁~ C₁₂Alkoxyl group, hydroxy
Group, -O (CO) OR₃₁, Or -O (CO) R₃₂Shows
You However, R₃₁, R₃₂Is C₁~ C₁₂Alkyl group of Ben
Zyl group; halogen atom, C₁~ C₆Alkyl group of C₁
~ C₆Aryl group which may be substituted with an alkoxyl group of
Indicates. ] [Chemical 3][In the formula, R_c, R_dAre each C_Four~ C₁₂The third-class al
Indicates a kill group. X and Y are NR₄₁, Or S
However, X and Y may be bonded in the form of N-A-N. here
And R₄₁Is a hydrogen atom, C₁~ C_TenAlkyl group of -CO
R₄₂Or -COOR ₄₃And A is C₁~ C_TenUntil saturation
Or represents an unsaturated alkylene group. Also, R ₄₂, R₄₃Is
Each C₁~ C₁₂Alkyl group; benzyl group; halogen
Atom, C₁~ C₆Alkyl group of C₁~ C₆Arco
An aryl group which may be substituted with a xyl group is shown. Also,
R₃₃~ R₄₀Are hydrogen atom, halogen atom, C₁~
C_TenAlkyl group of C₁~ C_TenAlkoxyl group, nit
B group, -N (R₄₄) (R₄₅), Or -SR₄₆Indicates. still,
R₃₃And R₃₄, R₃₄And R₃₅, R₃₅And R₃₆, R₃₇And R₃₈, R
₃₈And R₃₉, R₃₉And R₄₀Each form a benzene ring
Good. Where R₄₄, R₄₅Are hydrogen atoms; C₁
~ C₁₂Alkyl group of C_Four~ C₁₂A cycloalkyl group of
Halogen atom, C₁~ C₆Alkyl group of C₁~ C₆of
An aralkyl group which may be substituted with an alkoxyl group;
Rogen atom, C₁~ C₆Alkyl group of C ₁~ C₆A
An aryl group which may be substituted with a rucoxyl group is shown,
R₄₄And R₄₅Is a pyrrolidino group with an adjacent nitrogen atom,
Forming a peridino or hexamethyleneimino group
Good. Also, R₄₆Is C₁~ C_TenIs an alkyl group. ] 2. The method for producing a thermosensitive recording medium according to claim 1, wherein the resin soluble in an organic solvent contains a resin soluble in an organic solvent and insoluble in water. 3. The production of a thermosensitive recording medium according to claim 1, wherein R _a , R _b , R _c and R _d in [Chemical formula 1], [Chemical formula 2] and [Chemical formula 3] are tert-butyl groups. Method. 4. The heat-sensitive recording according to claim 1, wherein the organic solvent is at least one selected from the group consisting of alcohols, ketones, esters, aliphatic hydrocarbons, naphthenic hydrocarbons, and aromatic hydrocarbons. Body manufacturing method.