JPH08169180A - Thermosensible recording material - Google Patents

Abstract

PURPOSE: To improve the coloring sensitivity and storage stability of colored image of a thermosensible recording material containing an electron donating color developing compound and an electron accepting compound, respectively, by incorporating additionally at least one kind of a compound expressed by a specified formula into the material. CONSTITUTION: Into a thermosensible material containing an electron donating color developing compound and an electron accepting compound is additionally incorporated at least one kind of a compound expressed by a formula, where R1 , R2 are hydrogen atom, alkyl group, or alkenyl group; R3 is alkyl group, alkenyl group, or aralkyl group; X is oxygen atom or sulfur atom. In this way, the thermosensible material with improved coloring sensitivity and storage stability of colored image is obtained.

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, and more particularly to a heat-sensitive recording material having improved color-developing sensitivity and storage stability of a color-developed image.

[0002]

2. Description of the Related Art Conventionally, a heat-sensitive recording material utilizing a color reaction between an electron-donating color-forming compound and an electron-accepting compound (developing agent) is well known (for example, JP-B-43-4).
160, JP-B-45-14039). The heat-sensitive recording material is relatively inexpensive and has the advantage that the recording device is compact and maintenance-free, and is therefore widely used in the fields of facsimile, recorder and printer.

Conventionally, phenolic compounds have been widely used as electron-accepting compounds, and among them, 2,2-
Although bis (4'-hydroxyphenyl) propane (also known as bisphenol A) is widely used because it is inexpensive and easily available, it is a thermosensitive recording using bisphenol A as an electron-accepting compound. There is a problem that the material has low color development sensitivity and storage stability of a color image is poor.

A heat-sensitive recording material containing a heat-fusible compound (sensitizer) in addition to the electron-donating color-forming compound and the electron-accepting compound to improve the color-developing sensitivity is also widely used. As a heat-fusible compound, terphenyls (Japanese Patent Publication 6)
No. 3-7958), benzyl 4-benzyloxybenzoate (JP-B-63-30878), naphthol derivative (JP-B-63-42590), benzyl biphenyls (JP-B-2-11437). , Diary
Luoxyalkane derivatives (JP-A-60-56588 and JP-A-61-16888), oxalate ester derivatives (JP-A-1-1583), and the like have been proposed. However, a heat-sensitive recording material containing these heat-fusible compounds has remarkably poor storage stability of the color image, and usually has poorer storage stability of the color image as compared with the case where the heat-fusible compound is not added. The current situation is that there is a problem. At present, there is a strong demand for a heat-sensitive recording material that overcomes the above-mentioned problems and is excellent in color development sensitivity and storage stability of a color image.

[0005]

The object of the present invention relates to a heat-sensitive recording material which has good color-developing sensitivity and has significantly improved storage stability of a color-developed image.

[0006]

The present inventors have arrived at the present invention as a result of earnest studies on a heat-sensitive recording material in order to meet the above-mentioned demand. That is, the present invention is a heat-sensitive recording material containing an electron-donating color-forming compound and an electron-accepting compound, which further contains at least one compound represented by the general formula (1).

[0007]

Embedded image (In the formula, R ₁ and R ₂ represent a hydrogen atom, an alkyl group or an alkenyl group, R ₃ represents an alkyl group, an aralkyl group or an alkenyl group, and X represents an oxygen atom or a sulfur atom.)

In the general formula (1) according to the present invention, R ₁
And R ₂ represents a hydrogen atom, an alkyl group or an alkenyl group, preferably a hydrogen atom, a chain alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 5 to 14 carbon atoms or an alkenyl group having 2 to 20 carbon atoms. And more preferably a hydrogen atom, a chain alkyl group having 1 to 4 carbon atoms, a cycloalkyl group or an allyl group, and a hydrogen atom is particularly preferable.

In the general formula (1), R ₃ represents an alkyl group, an aralkyl group or an alkenyl group, and the aryl group in the aralkyl group may have a substituent, for example, a lower alkyl group or a lower alkoxy group. Alternatively, it may be substituted with a halogen atom. R3 is preferably a chain alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 5 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms, and more preferably , A chain alkyl group having 1 to 10 carbon atoms, a cyclohexyl group, a benzyl group, and an allyl group.

In the general formula (1), X represents an oxygen atom or a sulfur atom, more preferably an oxygen atom.

In the compound represented by the general formula (1) according to the present invention, the R ₃ O-group may be located at any of the para-position, meta-position or ortho-position with respect to the ether bond or the thioether bond. Good, and preferably para or meta.

Among the compounds represented by the general formula (1) according to the present invention, preferred examples include the following general formula (1-
The compound represented by a) and general formula (1-b) can be mentioned.

[0013]

Embedded image

[0014]

[Chemical 4] (In the formula, R ₁ , R ₂ , R ₃ and X are the same as above)

Specific examples of the compound represented by the general formula (1) according to the present invention include the following compounds, but the present invention is not limited thereto. Exemplified compound No. 1.4,4'-bis (4 "-methyloxyphenoxy)
Diphenyl sulfone 2.4,4'-bis (4 "-ethyloxyphenoxy)
Diphenyl sulfone 3.4,4'-bis (4 "-n-propyloxyphenoxy) diphenyl sulfone 4.4,4'-bis (4" -isopropyloxyphenoxy) diphenyl sulfone 5.4,4'-bis (4 7. "-N-Butyloxyphenoxy) diphenylsulfone 6.4,4'-bis (4" -isobutyloxyphenoxy) diphenylsulfone 7.4,4'-bis (4 "-tert-butyloxyphenoxy) diphenylsulfone 4,4'-bis (4 "-n-pentyloxyphenoxy) diphenyl sulfone 9.4,4'-bis (4" -isopentyloxyphenoxy) diphenyl sulfone 10.4,4'-bis (4 "-n -Hexyloxyphenoxy) diphenyl sulfone

11.4,4'-bis (4 "-n-heptyloxyphenoxy) diphenyl sulfone 12.4,4'-bis (4" -n-octyloxyphenoxy) diphenyl sulfone 13.4,4'- Bis [4 ”-(2-ethylhexyl)
Oxyphenoxy] diphenyl sulfone 14.4,4'-bis (4 "-n-nonyloxyphenoxy) diphenyl sulfone 15.4,4'-bis (4" -n-decyloxyphenoxy) diphenyl sulfone 16.4,4 '-Bis (4 "-n-dodecyloxyphenoxy) diphenyl sulfone 17.4,4'-bis (4" -cyclopentyloxyphenoxy) diphenyl sulfone 18.4,4'-bis (4 "-cyclohexyloxyphenoxy) diphenyl Sulfone 19.4,4'-bis [4 "-(4-methylcyclohexyl) oxyphenoxy] diphenyl sulfone 20.4,4'-bis (4" -cyclooctyloxyphenoxy) diphenyl sulfone

21.4,4'-bis (4 "-allyloxyphenoxy) diphenylsulfone 22.4,4'-bis [4"-(2-methyl-2-propenyl) oxyphenoxy] diphenylsulfone 23.4 , 4'-Bis [4 "-(3-methyl-2-propenyl) oxyphenoxy] diphenylsulfone 24.4,4'-bis [4"-(3,3-dimethyl-2
-Propenyl) oxyphenoxy] diphenyl sulfone 25.4,4'-bis (4 "-benzyloxyphenoxy) diphenyl sulfone 26.4,4'-bis [4"-(4-methylbenzyl)
Oxyphenoxy] diphenyl sulfone 27.4,4′-bis [4 ″-(4-methoxybenzyl) oxyphenoxy] diphenyl sulfone 28.4,4′-bis [4 ″-(4-chlorobenzyl)
Oxyphenoxy] diphenyl sulfone 29.4,4'-bis (3 "-methyloxyphenoxy) diphenyl sulfone 30.4,4'-bis (3" -ethyloxyphenoxy) diphenyl sulfone

31.4,4'-bis (3 "-n-butyloxyphenoxy) diphenyl sulfone 32.4,4'-bis (3" -n-hexyloxyphenoxy) diphenyl sulfone 33.4,4'- Bis (3 "-n-octyloxyphenoxy) diphenyl sulfone 34.4,4'-bis [3"-(2-ethylhexyl)
Oxyphenoxy] diphenyl sulfone 35.4,4'-bis (3 "-n-decyloxyphenoxy) diphenyl sulfone 36.4,4'-bis (3" -n-dodecyloxyphenoxy) diphenyl sulfone 37.4,4 '-Bis (3 "-cyclohexyloxyphenoxy) diphenyl sulfone 38.4,4'-bis (3" -allyloxyphenoxy) diphenyl sulfone 39.4,4'-bis [3 "-(2-methyl-2- Propenyl) oxyphenoxy] diphenyl sulfone 40.4,4′-bis (3 ″ -benzyloxyphenoxy) diphenyl sulfone

41.4,4'-bis (4 "-allyloxy-3" -methylphenoxy) diphenylsulfone 42.4,4'-bis (4 "-methyloxy-3" -ethylphenoxy) diphenylsulfone 43. 4,4'-bis (4 "-allyloxy-3" -n
-Propylphenoxy) diphenyl sulfone 44.4,4'-bis (4 "-benzyloxy-3"-
Isopropylphenoxy) diphenyl sulfone 45.4,4′-bis (4 ″ -allyloxy-3 ″ -n
-Butylphenoxy) diphenyl sulfone 46.4,4'-bis (4 "-methyloxy-3" -t
ert-Butylphenoxy) diphenyl sulfone 47.4,4′-bis (4 ″ -allyloxy-3 ″ -cyclohexylphenoxy) diphenyl sulfone 48.4,4′-bis (4 ″ -methyloxy-3 ″ -allylphenoxy) Diphenyl sulfone 49.4,4′-bis (4 ″ -allyloxy-2 ″ -methylphenoxy) diphenyl sulfone 50.4,4′-bis (4 ″ -allyloxy-2 ″ -t
ert-butylphenoxy) diphenyl sulfone

51.4,4'-bis (3 "-benzyloxy-4" -methylphenoxy) diphenylsulfone 52.4,4'-bis (3 "-n-butyloxy-4"
-Ethylphenoxy) diphenyl sulfone 53.4,4'-bis (3 "-allyloxy-4" -n
-Propylphenoxy) diphenyl sulfone 54.4,4'-bis (3 "-methyloxy-4" -t
ert-Butylphenoxy) diphenylsulfone 55.4,4′-bis (3 ″ -allyloxy-4 ″ -allylphenoxy) diphenylsulfone 56.4,4′-bis (3 ″ -methyloxy-2 ″ -allylphenoxy) Diphenyl sulfone 57.4,4'-bis (4 "-allyloxy-2",
5 "-di-tert-butylphenoxy) diphenylsulfone 58.4- (4" -allyloxy-3 "-methylphenoxy) phenyl-4 '-(4"-allyloxy-2'-
Methylphenoxy) phenyl sulfone 59.4,4'-bis (4 "-allyloxyphenylthio) diphenyl sulfone 60.4,4'-bis (3" -allyloxyphenylthio) diphenyl sulfone

The compound represented by the general formula (1) can be produced, for example, according to the method described in Macromolecules, 1994, vol. 27, p. That is, for example, 4,4′-bis (4-allyloxyphenoxy) diphenyl sulfone (melting point 105 to 106 ° C.)
Can be suitably produced by reacting an allyl halide with a 4,4′-bis (hydroxyphenoxy) diphenylsulfone derivative in the presence of a base.

The heat-sensitive recording material of the present invention is a heat-sensitive recording material containing an electron-donating color forming compound and an electron-accepting compound, and further contains at least one compound represented by the general formula (1).

In the heat-sensitive recording material of the present invention, the use ratio of the electron-donating color-forming compound, the electron-accepting compound and the compound represented by the general formula (1) is not particularly limited, but it is usually an electron. The electron-accepting compound is used in an amount of 50 to 700 parts by weight, preferably 100 to 500 parts by weight, based on 100 parts by weight of the donative color forming compound, and the compound represented by the general formula (1)
10 to 500 parts by weight, preferably 2
It is desirable to use 0 to 400 parts by weight.

Examples of the colorless or light-colored electron-donating color-forming compound used in the present invention include triarylmethane compounds, diarylmethane compounds, rhodamine-lactam compounds, fluorane compounds, indolylphthalide compounds, divinyl. Examples thereof include various known electron-donating color-forming compounds such as phthalide compounds, pyridine compounds, spiro compounds, fluorene compounds and thiazine compounds.

Among the above-mentioned electron-donating color forming compounds,
A fluoran compound is preferable, and a fluoran compound represented by formula (A) is more preferable.

[0026]

Embedded image (In the formula, A and B are an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkoxyalkyl group having 3 to 8 carbon atoms, an aryl group having 6 to 10 carbon atoms, or a tetrahydrofurfuryl group. Further, A and B may be bonded to form a pyrrolidine ring, a piperidine ring or a morpholine ring, and X is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or Represents a halogen atom, Y and Z are hydrogen atom, halogen atom, carbon number 1
Represents an alkyl group or a trifluoromethyl group of 4)

To give some specific examples of the electron-donating color-forming compound, the triarylmethane compounds are:
For example, 3,3-bis (4-dimethylaminophenyl)
-6-Dimethylaminophthalide ["Crystal Violet Lactone"], 3,3-bis (4-dimethylaminophenyl) phthalide, 3- (4-dimethylaminophenyl) -3- (4-diethylaminophenyl) -6- Dimethylaminophthalide, 3,3-bis (9-ethylcarbazol-3-yl) -6-dimethylaminophthalide, 3
Examples include-(4-dimethylaminophenyl) -3- (1-methylpyrrol-3-yl) -6-dimethylaminophthalide.

Examples of the diarylmethane compound include 4,4-bis-dimethylaminobenzhydrin benzyl ether, N-halophenyl-leukoauramine,
N-2,4,5-trichlorophenyl leuco auramine and the like.

As the rhodamine-lactam compound,
For example, rhodamine-B-anilinolactam, rhodamine- (4-nitroanilino) lactam, rhodamine-B
-(2-chloroanilino) lactam and the like.

Examples of the fluoran compound include:
3,6-dimethoxyfluorane, 3-diethylamino-
6-methoxyfluorane, 3-dimethylamino-7-methoxyfluorane, 3-diethylamino-7-methylfluorane, 3-N-cyclohexyl-Nn-butylamino-7-methylfluorane, 3-N- Ethyl-N-isopentylamino-7-methylfluorane, 3-diethylamino-7-methoxy7luorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-6-
Methyl-7-chlorofluorane, 3-diethylamino-
6,7-dimethylfluorane, 3,6-bis (diphenylamino) fluorane,

3-diethylamino-7-dibenzylaminofluorane, 3-di-n-butylamino-7-dibenzylaminofluorane, 3-diethylamino-7-di-
n-hexylaminofluorane, 3-diethylamino-
7-n-octylaminofluorane, 3-diethylamino-7-anilinofluorane, 3-N-ethyl-N-isopentylamino-7-anilinofluorane,

3-Diethylamino-7- (2'-chlorophenylamino) fluorane, 3-diethylamino-7
-(3'-chlorophenylamino) fluorane, 3-diethylamino-7- (2 ', 3'-dichlorophenylamino) fluorane, 3-diethylamino-7- (3'-
Trifluoromethylphenylamino) fluorane, 3-
Di-n-butylamino-7- (2'-chlorophenylamino) fluorane, 3-diethylamino-7- (2'-
Fluorophenylamino) fluorane, 3-di-n-butylamino-7- (2′-fluorophenylamino) fluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3-di-n-butylamino -6-chloro-7-anilinofluorane, 3-diethylamino-6
-Methoxy-7-anilinofluorane, 3-di-n-butylamino-6-ethoxy-7-anilinofluorane,

3-Pyrrolidino-6-methyl-7-anilinofluorane, 3-morpholino-6-methyl-7-anilinofluorane, 3-dimethylamino-6-methyl-7
-Anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-di-n-butylamino-6-methyl-7-anilinofluorane, 3-di-n
-Pentylamino-6-methyl-7-anilinofluorane, 3-di-n-octylamino-6-methyl-7-anilinofluorane, 3-N-n-propyl-N-methylamino-6- Methyl-7-anilinofluorane, 3-N
-N-butyl-N-methylamino-6-methyl-7-anilinofluorane, 3-N-n-butyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-
Isobutyl-N-methylamino-6-methyl-7-anilinofluorane, 3-N-isobutyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-Nn
-Pentyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-isopentyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-
n-hexyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-n-octyl-N-ethylamino-6-methyl-7-anilinofluorane,

3-N-cyclopentyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-cyclohexyl-N-methylamino-6-methyl-7-anilinofluorane, 3-N -Cyclohexyl-N-n-
Propylamino-6-methyl-7-anilinofluorane, 3-N-cyclohexyl-Nn-butylamino-
6-methyl-7-anilinofluorane, 3-N-cyclohexyl-Nn-hexylamino-6-methyl-7-
Anilinofluorane, 3-N-cyclohexyl-Nn
-Octylamino-6-methyl-7-anilinofluorane,

3-N- (2'-methoxyethyl) -N-
Isobutylamino-6-methyl-7-anilinofluorane, 3-N- (2'-ethoxyethyl) -N-ethylamino-6-methyl-7-anilinofluorane, 3-N-
(3'-Methoxypropyl) -N-methylamino-6-
Methyl-7-anilinofluorane, 3-N- (3'-methoxypropyl) -N-ethylamino-6-methyl-7
-Anilinofluorane, 3-N- (3'-ethoxypropyl) -N-methylamino-6-methyl-7-anilinofluorane, 3-N- (3'-ethoxypropyl) -N
-Ethylamino-6-methyl-7-anilinofluorane, 3-N- (2'-tetrahydrofurfuryl) -N-
Ethylamino-6-methyl-7-anilinofluorane,
3-N- (4'-methylphenyl) -N-ethylamino-6-methyl-7-anilinofluorane,

3-Diethylamino-6-ethyl-7-anilinofluorane, 3-diethylamino-6-methyl-
7- (3'-methylphenylamino) fluorane, 3-
Diethylamino-6-methyl-7- (2 ', 6'-dimethylphenylamino) fluorane, 3-di-n-butylamino-6-methyl-7- (2', 6'-dimethylphenylamino) fluorane, 3 -Di-n-butylamino-
7- (2 ', 6'-dimethylphenylamino) fluorane, 2,2-bis [4'-(3-N-cyclohexyl-
N-methylamino-6-methylfluorane) -7-ylaminophenyl] propane, 3- [4 ′-(4-phenylaminophenyl) aminophenyl] amino-6-methyl-7-chlorofluorane and the like. .

Examples of the indolylphthalide compound include 3,3-bis (1,2-dimethylindole-3)
-Yl) -5-dimethylaminophthalide, 3,3-bis (1,2-dimethylindol-3-yl) -6-dimethylaminophthalide, 3,3-bis (2-phenylindol-3-yl) ) -6-Dimethylaminophthalide,
3,3-bis (1-ethyl-2-methylindole-3
-Yl) phthalide, 3,3-bis (1-octyl-2-
Methylindol-3-yl) phthalide, 3- (4-dimethylaminophenyl) -3- (1,2-dimethylindol-3-yl) phthalide, 3- (4-dimethylaminophenyl) -3- (2- Methylindol-3-yl) phthalide, 3- (2-ethoxy-4-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, 3- (2-ethoxy-4-dibutyl) Aminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, 3- (2-ethoxy-4-diethylaminophenyl) -3- (1-octyl-2-methylindol-3-yl) ) There are phthalides.

Examples of the divinylphthalide compound include 3,3-bis [2,2-bis (4-dimethylaminophenyl) ethenyl] -4,5,6,7-tetrachlorophthalide and 3,3. -Bis [2,2-bis (4-pyrrolidinophenyl) ethenyl] -4,5,6,7-tetrabromophthalide, 3,3-bis [2- (4-methoxyphenyl) -2- (4 -Dimethylaminophenyl) ethenyl]
-4,5,6,7-Tetrachlorophthalide, 3,3-bis [2- (4-methoxyphenyl) -2- (4-pyrrolidinophenyl) ethenyl] -4,5,6,7-tetra Chlorophthalide etc.

Examples of the pyridine compound include 3-
(2-Ethoxy-4-diethylaminophenyl) -3-
(1-Ethyl-2-methylindol-3-yl) -4
Or 7-azaphthalide, 3- (2-ethoxy-4-diethylaminophenyl) -3- (1-ethyl-2-phenylindol-3-yl) -4 or 7-azaphthalide, 3- (2-ethoxy-4-) Diethylaminophenyl) -3- (1-octyl-2-methylindole-3
-Yl) -4 or 7-azaphthalide, 3- (2-hexyloxy-4-diethylaminophenyl) -3- (1
-Ethyl-2-methylindol-3-yl) -4 or 7-azaphthalide, 3- (2-n-butoxy-4-diethylaminophenyl) -3- (1-ethyl-2-phenylindol-3-yl) -4 or 7-azaphthalide, 3- (4-diethylamino-2-methylphenyl)
-3- (1-Ethyl-2-methylindol-3-yl) -4 or 7-azaphthalide, 3- (4-diethylamino-2-methylphenyl) -3- (1-n-octyl-2-methylindole -3-yl) -4 or 7-
Azaphthalide, 3,3-bis (4-diethylamino-2)
-Methoxyphenyl) -4 or 7-azaphthalide,
Examples include 3,3-bis (4-diethylamino-2-ethoxyphenyl) -4 or 7-azaphthalide.

Examples of spiro compounds include 3-methyl-spiro-dinaphthopyran, 3-ethyl-spiro-
Dinaphthopyran, 3-phenyl-spiro-dinaphthopyran, 3-benzyl-spiro-dinaphthopyran, 3-methyl-naphtho- (3-methoxybenzo) spiropyran, 3
-Propyl-spiro-dibenzopyran and the like.

Examples of fluorene compounds include:
3,6-bis (dimethylamino) fluorene-9-spiro-3 '-(6'-dimethylamino) phthalide, 3-diethylamino-6- (N-allyl-N-methylamino)
Fluorene-9-spiro-3 '-(6'-dimethylamino) phthalide, 3,6-bis (dimethylamino) -spiro [fluorene-9,6'-6'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-9,6'-6'H-chromeno (4,3-b) indole] and so on.

Examples of thiazine compounds include benzoyl leuco methylene blue and 4-nitrobenzoyl leuco methylen blue.

These electron-donating color forming compounds may be used alone or in combination.

As the electron-donating color forming compound,
Fluoran compounds that develop black color are preferable, and among them,
Preferably, di-n-butylamino-7- (2'-chlorophenylamino) fluorane, 3-dimethylamino-
6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-di-
n-Butylamino-6-methyl-7-anilinofluorane, 3-di-n-pentylamino-6-methyl-7-anilinofluorane, 3-N-n-propyl-N-methylamino-6 -Methyl-7-anilinofluorane, 3-N
-N-butyl-N-methylamino-6-methyl-7-anilinofluorane, 3-N-isobutyl-N-methylamino-6-methyl-7-anilinofluorane, 3-N-
Isobutyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-isopentyl-N-ethylamino-6-methyl-7-anilinofluorane, 3-N-
(2'-Methoxyethyl) -N-isobutylamino-6
-Methyl-7-anilinofluorane, 3-N- (3'-
Ethoxypropyl) -N-ethylamino-6-methyl-
7-anilinofluorane and 3-diethylamino-6-methyl-7- (3′-methylphenylamino) fluorane.

The electron-accepting compound used in the present invention is not particularly limited, but may be a phenol derivative or a metal salt thereof, an organic acid derivative or a metal salt thereof,
Various known electron-accepting compounds such as organic electron-accepting compounds such as complexes and urea derivatives, or inorganic electron-accepting compounds can be mentioned.

Specific examples of these electron-accepting compounds include, for example, 4-tert-butylphenol and 4-tert-butylphenol.
Octylphenol, 4-phenylphenol, 1-naphthol, 2-naphthol, hydroquinone, resorcinol, 4-tert-octylcatechol, 2,2'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl ether, 2,2-bis (4 '. -Hydroxyphenyl) propane ["bisphenol A"], 1,1-bis (4'-hydroxyphenyl) cyclohexane, 2,2
-Bis (4'-hydroxy-3'-methylphenyl) propane, 1,3-bis (4'-hydroxycumyl) benzene, 1,4-bis (4'-hydroxycumyl) benzene, 1,3,3 5-tris (4'-hydroxycumyl) benzene, 2,2-bis (4'-hydroxyphenyl) acetic acid ethyl ester, 4,4- (4'-hydroxyphenyl) pentanoic acid-n-butyl ester, 4- Hydroxybenzoic acid benzyl ester, 4-hydroxybenzoic acid phenethyl ester, 2,4-dihydroxybenzoic acid phenoxyethyl ester, 4-hydroxyphthalic acid dimethyl ester, gallic acid-n-propyl ester, gallic acid-n-octyl ester, gallic acid Acid-n-dodecyl ester, gallic acid-n-octadecyl ester,

Hydroquinone monobenzyl ether, bis (3-methyl-4-hydroxyphenyl) sulfide, bis (2-methyl-4-hydroxyphenyl) sulfide, bis (3-phenyl-4-hydroxyphenyl) sulfide, bis (3 -Cyclohexyl-4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfone, bis (3-allyl-4-hydroxyphenyl) sulfone, bis (3-phenyl-4-hydroxy) Phenyl) sulfone, 4-hydroxy-4'-methyldiphenyl sulfone, 4-hydroxy-4'-te
rt-Butyldiphenylsulfone, 4-hydroxy-
4'-chlorodiphenyl sulfone, 4-hydroxy-
4'-methoxydiphenyl sulfone, 4-hydroxy-4'-n-propoxydiphenyl sulfone, 4-hydroxy-4'-isopropoxydiphenyl sulfone, 4-hydroxy-4'-n-butoxydiphenyl sulfone, 4-hydroxy-4 '-Benzyloxydiphenyl sulfone, 3,4-dihydroxy-4'-methyldiphenyl sulfone, 2,4'-dihydroxydiphenyl sulfone,

2-methoxy-4'-hydroxydiphenyl sulfone, 2-ethoxy-2'-hydroxydiphenyl sulfone, 4-hydroxy-3-methyl-4'-
n-propoxydiphenyl sulfone, bis (2-hydroxy-5-tert-butylphenyl) sulfone, bis (2-hydroxy-5-chlorophenyl) sulfone,
Bis [4- (3'-hydroxyphenyloxy) phenyl] sulfone, 4-hydroxybenzophenone, 2,
4-dihydroxybenzophenone, 2,4'-dihydroxybenzophenone, 4,4'-dihydroxybenzophenone, 1,7-di (4'-hydroxyphenylthio)
Phenol derivatives such as -3,5-dioxaheptane and 1,5-di (4'-hydroxyphenylthio) -3-oxapentane, or metal salts of these phenol derivatives (for example, nickel, zinc, aluminum, calcium) Metal salts such as),

For example, 4- (2'-phenoxyethoxy) salicylic acid, 4- [2 '-(4-methoxyphenoxy) ethoxy] salicylic acid, 5- [4'-(2- [4-
Methoxyphenoxy] ethoxy) cumyl] salicylic acid,
4- [3 '-(4-methylphenylsulfonyl) propoxy] salicylic acid, 4-n-butyloxycarbonylaminosalicylic acid, 4-n-octyloxycarbonylaminosalicylic acid, 4-n-nonyloxycarbonylaminosalicylic acid, 4-n -Decyloxycarbonylaminosalicylic acid, 5-cyclohexyloxycarbonylaminosalicylic acid, 1-naphthoic acid, 2-naphthoic acid, 1-
Hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, 2-hydroxy-6-naphthoic acid, 1-acetyloxy-2-naphthoic acid, 2-acetyloxy-1
-Naphthoic acid, 2-acetyloxy-3-naphthoic acid,
Phthalic acid monobenzyl ester, phthalic acid monophenyl ester, isophthalic acid, terephthalic acid, 4-methylbenzoic acid, 2-benzoylbenzoic acid, 2- (4'-chlorobenzoyl) benzoic acid, 4-nitrobenzoic acid, 4- Chlorobenzoic acid, 4-trifluoromethylbenzoic acid, 4-formylbenzoic acid, 4-cyanobenzoic acid, organic acid derivatives such as stearic acid, or metal salts of these organic acid derivatives (for example, nickel, zinc, aluminum, Metal salts such as calcium),

For example, complexes such as zinc thiocyanate antipyrine complex and molybdic acid acetylacetone complex such as N, N′-diphenylthiourea, N, N′-di (3-trifluoromethylphenyl) thiourea, N,
N'-di (3-chlorophenyl) thiourea, 1,4-di (3'-chlorophenyl) -3-thiosemicarbazide,
Organic electron-accepting compounds such as urea derivatives such as N-phenyl-N '-(4-methylphenylsulfonyl) urea and 4,4'-bis (4 "-methylphenylsulfonylcarbonylamino) diphenylmethane

Examples thereof include inorganic electron-accepting compounds such as acid clay, attapulgite, activated clay, aluminum chloride, zinc chloride and zinc bromide, but the invention is not limited to these compounds. These electron-accepting compounds can be used in combination.

As described above, the heat-sensitive recording material of the present invention is a heat-sensitive recording material containing an electron-donating color forming compound and an electron-accepting compound, and further contains a compound represented by the general formula (1). Although it is a recording material, if desired, a heat-fusible compound (melting point of about 60-
150 ° C. compound) may be added to the heat-sensitive recording material of the present invention. In this case, the proportion of the amount of these compounds used is not particularly limited, but usually 50 to 7 parts by weight of the electron accepting compound relative to 100 parts by weight of the electron donating color forming compound.
00 parts by weight, preferably 100 to 500 parts by weight, 10 to 500 parts by weight of the compound represented by the general formula (1), preferably 20 to 400 parts by weight, and 10 to 50 parts of the heat-fusible compound.
It is desirable to use 0 parts by weight, preferably 20 to 400 parts by weight. Specific examples of the heat-fusible compound include, for example, caproic acid amide, capric acid amide, palmitic acid amide, stearic acid amide, oleic acid amide, erucic acid amide, linoleic acid amide, linolenic acid amide, and N-ethylcaprin. Acid amide, N-butyllauric acid amide, N-methylstearic acid amide, N-methyloleic acid amide, N-stearylcyclohexylamide, N-octadecylacetamide, N-oleinacetamide, stearylurea, stearic acid anilide, benzanilide, linole Acid anilide, acetoacetic acid anilide, o-acetoacetic acid toluidide, p-acetoacetic acid anisidide, N-ethylcarbazole, 4-methoxydiphenylamine, N-hydroxymethylstearic acid amide,
Nitrogen-containing compounds such as ethylenebisstearic acid amide,

For example, 4-benzyloxybenzoic acid benzyl ester, 2-naphthoic acid phenyl ester, 1-
Hydroxy-2-naphthoic acid phenyl ester, oxalic acid dibenzyl ester, oxalic acid di (4-methylbenzyl) ester, oxalic acid di (4-chlorobenzyl) ester, adipic acid diphenyl ester, glutaric acid diphenacyl ester, diester Ester compounds such as (4-methylphenyl) carbonate and terephthalic acid dibenzyl ester, for example, hydrocarbons such as 4-benzylbiphenyl, m-terphenyl, fluorene, fluoranthene, 2,6-diisopropylnaphthalene and 3-benzylacenaphthene. Compound,

For example, 2-benzyloxynaphthalene,
2- (4'-methylbenzyloxy) naphthalene, 1,
4-diethoxynaphthalene, 1,2-diphenoxyethane, 1,2-bis (3′-methylphenoxy) ethane,
1-phenoxy-2- (4'-methylphenoxy) ethane, 1-phenoxy-2- (4'-ethylphenoxy)
Ethane, 1- (4'-methoxyphenoxy) -2-phenoxyethane, 1- (4'-methoxyphenoxy) -2
-(3'-methylphenoxy) ethane, 1- (4'-methoxyphenoxy) -2- (2'-methylphenoxy)
Ethane, 1,2-bis (4'-methoxyphenylthio)
Ethane, 1,5-bis (4'-methoxyphenoxy)-
3-oxapentane, 1,4-bis (2′-vinyloxyethoxy) benzene, 4- (4′-methylphenoxy) biphenyl, 1,4-bis (2′-chlorobenzyloxy) benzene, 4,4 ′ -Di-n-butoxydiphenyl sulfone, 1,2-diphenoxybenzene, 1,
4-bis (2'-chlorophenoxy) benzene, 1,4
-Bis (4'-methylphenoxy) benzene, 1,4-
Bis (3'-methylphenoxymethyl) benzene, 4-
Chlorobenzyloxy- (4'-ethoxybenzene),
4,4'-bis (phenoxy) diphenyl ether,
Ether compounds such as 4,4′-bis (phenoxy) diphenylthioether, 1,4-bis (4′-benzylphenoxy) benzene and 1,4-bis [(4′-methylphenyloxy) methoxymethyl] benzene,

For example, 1,4-diglycidyloxybenzene, 4-benzyloxy-4 '-(2-methylglycidyloxy) diphenylsulfone, 4- (4-methylbenzyloxy) -4'-glycidyloxydiphenylsulfone, Epoxy compounds such as N-glycidyl phthalimide,

For example, 2- (2'-hydroxy-5'-
Methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-te
rt-Butylphenyl) benzotriazole, 2- (2 '
-Hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-
Hydroxy-3 ', 5'-di-tert-butylphenyl)
-5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-
Examples thereof include triazole compounds such as octylphenyl) benzotriazole, but are not limited thereto. These heat-fusible compounds may be used alone or in combination.

The heat-sensitive recording material of the present invention can be manufactured by a known method without using a special method. Generally, in the presence of water, an electron-donating color-forming compound, an electron-accepting compound, a compound represented by the general formula (1), and, if desired, a heat-fusible compound together, or Separately, ball mill, sand mill (vertical type,
A horizontal type), an attritor, a colloidal mill, or the like, and a pulverizer may be pulverized and dispersed to a particle size of usually 3 μm or less, preferably 2 μm or less, and mixed to prepare a coating liquid for a recording layer. .

A binder is usually added to the coating solution in an amount of about 5 to 50% by weight based on the total solid content. As the binder, a water-soluble binder is generally used, for example,
Polyvinyl alcohol, carboxy modified polyvinyl alcohol, sulfonation modified polyvinyl alcohol, polyvinyl alcohol derivatives such as alkyl modified polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and other cellulose derivatives, epichlorohydrin modified polyamide, ethylene-maleic anhydride Polymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylic acid, polyacrylamide, methylol-modified polyacrylamide, starch, starch derivative (oxidized starch, etherified starch, etc.), casein, gelatin , Gum arabic, and the like, but are not limited thereto.

Further, if necessary, a pigment,
A water-insoluble binder, metal soap, wax, surfactant, ultraviolet absorber, ultraviolet stabilizer, crosslinking agent, hindered phenol, phosphorus compound, defoaming agent, etc. are added. As the pigment, for example, calcium carbonate, barium carbonate,
Inorganic pigments such as magnesium carbonate, zinc carbonate, zinc oxide, aluminum oxide, titanium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, talc, wax, kaolin, clay, diatomaceous earth, silica, styrene microballs, nylon particles , Urea-formalin fillers, polyethylene particles, cellulose fillers, starch particles and other organic pigments are used.

As the water-insoluble binder, synthetic rubber latex or synthetic resin emulsion is generally used,
Examples thereof include styrene-butadiene rubber latex, acrylonitrile-butadiene latex, methyl acrylate-butadiene rubber latex, vinyl acetate emulsion and the like. Examples of the metal soap include metal salts of higher fatty acids such as zinc stearate, calcium stearate, aluminum stearate and zinc oleate. As a wax,
Examples thereof include paraffin wax, microcrystalline wax, carboxy-modified paraffin wax, carnauba wax, polyethylene wax, polystyrene wax, candelia wax, montan wax, and higher fatty acid ester.

As the surfactant (dispersant), for example,
Sulfosuccinic acid-based alkali metal salts [for example, di (n-
Hexyl) sulfosuccinic acid, di (2-ethylhexyl)
Sodium salt of sulfosuccinic acid and the like], sodium salt of dodecylbenzenesulfonic acid, sodium salt of lauryl alcohol sulfate, fatty acid metal salt, fluorine-containing surfactant and the like.

Examples of the ultraviolet absorbers and ultraviolet stabilizers include cinnamic acid derivatives, benzophenone derivatives, triazole derivatives, salicylic acid derivatives and hindered amine derivatives. Examples of the cross-linking agent include aldehyde derivatives such as glyoxal, epoxy compounds, polyamide resins, diglycidyl compounds, aziridine compounds, magnesium chloride and ferric chloride.

The hindered phenol is preferably a phenol derivative in which at least one of the ortho positions of the phenolic hydroxyl group is substituted with a branched alkyl group.
2,6-diisopropyl-4-methylphenol, 2,
6-di-tert-butyl-4-methylphenol, 2-te
rt-Butyl-4-methoxyphenol, 2,5-di-te
rt-octyl-4-methoxyphenol, 2,5-di-
tert-butylhydroquinone, 2,5-di-tert-octylhydroquinone, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,1,3-tris (2 -Methyl-4-hydroxy-5-cyclohexylphenyl) butane, 1,1,3-
Tris (2-ethyl-4-hydroxy-5-tert-butylphenyl) butane, 1,1,3-tris (3,5-di-tert-butyl-4-hydroxyphenyl) butane,
1,1,3-tris (2-methyl-4-hydroxy-5)
-Tert-butylphenyl) propane, 1,1-bis (2
-Methyl-5-tert-butyl-4-hydroxy) butane, tetrakis [methylene-3- (3 ', 5'-di-te
rt-Butyl-4'-hydroxyphenyl) propionate] methane, 2,2'-methylene-bis (6-tert-butyl-4-methylphenol), 2,2'-methylene-
Bis (6-tert-butyl-4-ethylphenol),
1,3,5-Trimethyl-2,4,6-tris (3,5
-Di-tert-butyl-4-hydroxybenzyl) benzene, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid,
1,3,5-tris (4-tert-butyl-3-hydroxy-2-methyl-6-ethylbenzyl) isocyanuric acid, bis (2-methyl-4-hydroxy-5-tert-butylphenyl) sulfide, etc. Can be mentioned.

As the phosphorus compound, a phosphate compound is preferable, for example, 2,2'-methylenebis (4-
Methyl-6-tert-butylphenyl) phosphate,
2,2'-methylenebis (4-ethyl-6-tert-butylphenyl) phosphate, 2,2'-methylenebis (4,6-di-tert-butylphenyl) phosphate,
Diphenyl phosphate, bis (4-tert-butylphenyl) phosphate, bis (2,4-ditert-butylphenyl) phosphate, bis (4-chlorophenyl)
Mention may be made of phosphates, bis (2-phenylphenyl) phosphates, bis (4-phenylphenyl) phosphates and the like, or salts of these metals (eg potassium, sodium, zinc, calcium, magnesium, aluminum).

In the heat-sensitive recording material of the present invention, the method for forming the recording layer is not particularly limited, and the recording layer can be formed according to a conventionally known technique. For example, the coating liquid for the heat-sensitive recording layer is coated on a support with an appropriate coating device such as an air knife coater, a blade coater, a bar coater, a short dwell coater, a gravure coater, a curtain coater, and a wire bar, and dried. Can form a recording layer.

The coating amount of the coating liquid is not particularly limited, but is generally 1.5 to 12 g / dry weight.
m ² approximately, preferably adjusted at about 2.5~10g / m ^2. The support is not particularly limited, but for example, paper, plastic sheet, synthetic paper, or a composite sheet or non-woven sheet combining these, a molded product, or a metal deposition product is used.

If necessary, a protective layer (overcoat layer) may be provided on the front surface and / or the back surface of the heat-sensitive recording layer, or a single layer or a plurality of layers of pigment (for example, between the support and the heat-sensitive recording layer) (for example, Providing an undercoat layer (undercoat layer) made of kaolin, calcium carbonate) or synthetic resin (for example, plastic spherical particles, plastic spherical hollow particles), between the heat-sensitive recording layer and the undercoat layer,
Alternatively, it is of course possible to provide an intermediate layer composed of a pigment, a binder, etc. between the heat-sensitive recording layer and the protective layer, and further, the back surface of the support is subjected to an adhesive treatment to form an adhesive label. Various known techniques in the manufacturing method of can be applied. Further, after forming the heat-sensitive recording layer and / or the protective layer, super calendering treatment can be performed.

[0068]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples,% represents% by weight.

Examples 1 to 13 [Preparation of thermal recording paper]

[0070]

[Table 1]

[0071]

[Table 2]

[0072]

[Table 3]

The above liquids A, B and C were dispersed by a sand grinding mill so that the average particle diameter was 1.5 μm to prepare a dispersion liquid.

Liquid A 100 g, liquid B 250 g, liquid C 250
g of the dispersion liquid and 23 g of 30% paraffin wax were mixed, and this was coated on a high-quality paper so that the dry coating amount was 5.0 g / m ^2, and dried to prepare a thermosensitive recording paper.

Table 1 shows the electron-donating color-forming compounds in the liquid A and the compounds represented by the general formula (1) in the liquid C used in each example.

[0076]

[Table 4]

Comparative Example 1 3-di-n-as the electron-donating color forming compound in solution A
A method similar to the method described in Examples except that butylamino-6-methyl-7-anilinofluorane was used and liquid C (dispersion liquid of the compound represented by the general formula (1)) was not used. Thus, a thermal recording paper was prepared.

Comparative Examples 2 to 5 3-di-n-as the electron-donating color forming compound in the liquid A
Butylamino-6-methyl-7-anilinofluorane was used, and instead of using the compound represented by the general formula (1) in solution C, the compounds shown in Table 2 were used. A thermal recording paper was prepared by the same method as that described in the examples.

[0079]

[Table 5]

[Evaluation of Thermal Recording Paper] 1. Color development performance test with respect to temperature Each thermosensitive recording paper is brought into contact with a metal block heated to each surface temperature for 5 seconds, and the color image density thereof is measured using a Macbeth densitometer (TR-524 type). The larger the value, the deeper the color.

2. Storage stability test for colored images Each thermal recording paper was loaded with a thermal paper coloring device (TH-P manufactured by Okura Electric Co., Ltd.
MD) was used to form a color image having a color density of 0.9 measured using a Macbeth densitometer (TR-524 type), and then a storage stability test was performed.

As the storage stability test, a moist heat resistance test and an oil resistance test were carried out, and the residual ratio of the colored image on each thermosensitive recording paper after each test was examined.

The moist heat resistance test was carried out at 40 ° C. for each thermosensitive recording paper.
The color image density after storage for 24 hours in 90% relative humidity was measured using a Macbeth densitometer to determine the residual rate of the color image.

In the oil resistance test, each thermosensitive recording paper was overlaid with a dioctyl phthalate-containing capsule coated paper, passed through a pressure roll and stored at 25 ° C. for 1 week. It was measured using a meter to determine the residual rate of the color image. Residual rate (%) = (colored image density after each test / colored image density before test (0.9)) × 100 The larger the value, the better the storage stability of the colored image.

Table 3 shows the results of the color development performance test with respect to the temperature of the thermosensitive recording paper prepared in Examples and Comparative Example 1.

[0086]

[Table 6]

As is apparent from Table 3, the heat-sensitive recording material of the present invention develops color rapidly at a lower temperature as compared with the conventional heat-sensitive recording material comprising an electron-donating color-forming compound and an electron-accepting compound. However, it can be said that it is a thermal recording material suitable for high speed recording.

Table 4 shows the results of the storage stability test of the color images of the thermosensitive recording papers produced in Examples 1 to 13 and Comparative Examples 1 to 5.

[0089]

[Table 7]

As is clear from Table 4, the heat-sensitive recording material of the present invention is superior in storage stability of a color image as compared with the known heat-sensitive recording material.

[0091]

According to the present invention, it is possible to provide a heat-sensitive recording material having a good color-developing sensitivity and excellent storage stability of a color-developed image.

Continued Front Page (72) Inventor Masakatsu Nakatsuka 1190 Kasamacho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A heat-sensitive recording material containing an electron-donating color-forming compound and an electron-accepting compound, which further contains at least one compound represented by the general formula (1). Embedded image (In the formula, R ₁ and R ₂ represent a hydrogen atom, an alkyl group or an alkenyl group, R ₃ represents an alkyl group, an alkenyl group or an aralkyl group, and X represents an oxygen atom or a sulfur atom.)