JP2000318314A - Heat-sensitive recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-sensitive recording material wherein a scratch resistance is favorable, and a head contamination is hard to occur, and also, a recording sensitivity is excellent, and an air bubble cloudiness is hard to occur as well. SOLUTION: In this heat-sensitive recording material, a supporting body is provided with at least a heat-sensitive recording layer, and the heat-sensitive recording material contains a compound represented by CH3CH2(CH2CH2)xCH2 CH2(OCH2CH2)yOH. In this case, x is an integer of 7-30, and y is an integer of 3-100.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat-sensitive recording material, and more particularly to a diazo compound-based heat-sensitive recording material that can be fixed.

[0002]

[Prior art]

[0003] Thermal recording has recently been developed because its recording apparatus is simple, reliable and maintenance-free. Using
Those utilizing a reaction between a diazonium salt compound and a coupler are widely known. In recent years, as a heat-sensitive recording material, researches on (1) improvement of characteristics such as (1) color density and color sensitivity (2) robustness of a color forming body have been earnestly conducted. However, thermal recording materials are exposed to sunlight for a long time,
When posted in an office or the like for a long period of time, the background portion is colored by light, and the image portion has a disadvantage of discoloration or fading. Various methods have been proposed to improve the coloring of the background portion and the discoloration and fading of the image portion, but sufficient results have not always been obtained.

On the other hand, needs for thermal recording systems are expanding in various fields such as facsimile machines, printers and labels. Accordingly, there is a demand for a higher-performance heat-sensitive recording material. The thermal recording material is heated by the thermal recording head in an image-like manner to record an image. Is required to be reduced. Therefore, conventionally, waxes (for example, zinc stearate, etc.), matting agents, pigments, and the like have been used to impart friction resistance and lubricity to the heat-sensitive recording material. However, with such means, friction resistance,
The improvement in lubricity is not always sufficient, and when the heat-sensitive recording material is a reflective material, the transparency and glossiness are reduced (when the heat-sensitive recording material is a transmission material, the haze is increased). Has the disadvantage that the component fusing to the thermal recording head, the printing surface, etc., causes troubles such as adhesion of dregs and gloss unevenness.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object the purpose of the present invention is to provide good glossiness and scratch resistance, hardly cause head dirt, excellent recording sensitivity, and excellent bubble opacity. Another object of the present invention is to provide a heat-sensitive recording material which does not easily cause heat.

[0006]

The above object can be attained by providing the following heat-sensitive recording material. (1) A thermosensitive recording material having at least a thermosensitive recording layer provided on a support, characterized by containing a compound represented by the following general formula (1). Formula _{(1) CH 3 CH 2 (} CH 2 CH 2) xCH 2 CH 2 (OCH 2 C
H ₂ ) yOH In the above formula, x represents an integer of 7 to 30, and y represents 3 to 100.
Represents an integer. (2) The thermosensitive recording layer according to (1), wherein the thermosensitive recording layer has at least one thermosensitive coloring layer containing a diazonium salt compound, a coupler that reacts with the diazonium salt compound and a binder as main components. Heat-sensitive recording material. (3) The heat-sensitive recording layer contains an electron-donating dye and an electron-accepting compound, and has a maximum absorption wavelength of 360.
A photo-fixing type thermosensitive recording layer containing a diazonium salt compound having a wavelength of ± 20 nm and a coupler which reacts with the diazonium salt compound to form a color, and a reaction between the diazonium salt compound having a maximum absorption wavelength of 400 ± 20 nm and the diazonium salt compound The heat-sensitive recording material according to (1), further comprising a light-fixing type heat-sensitive recording layer containing a color-forming coupler. (4) The thermosensitive recording layer has a maximum absorption wavelength of 340 ± 20.
a light-fixing type heat-sensitive recording layer containing a diazonium salt compound having a wavelength of not more than nm and a coupler that undergoes a color reaction with the diazonium salt compound, and reacting the diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm with the diazonium salt compound. A light-fixing type heat-sensitive recording layer containing a color-forming coupler,
The photothermographic recording layer according to the above (1), comprising: a light-fixing type thermosensitive recording layer containing a diazonium salt compound having a maximum absorption wavelength of 400 ± 20 nm and a coupler which reacts with the diazonium salt compound to form a color. Thermal recording material. (5) Any one of (1) to (4) above, wherein a protective layer is provided on the heat-sensitive recording layer.
2. The heat-sensitive recording material according to item 1. (6) The heat-sensitive recording material according to (5), wherein a light transmittance adjusting layer is further provided on the heat-sensitive recording layer. (7) The heat-sensitive recording material according to the above (5) or (6), wherein the protective layer contains inorganic ultrafine particles. (8) The heat-sensitive recording material according to the above (6) or (7), wherein the light transmittance adjusting layer contains inorganic ultrafine particles. (9) The heat-sensitive recording material according to any one of the above (5) to (8), wherein the protective layer contains a compound represented by the above general formula. (10) The heat-sensitive recording material according to any one of (6) to (9), wherein the light transmittance adjusting layer contains a compound represented by the general formula. (11) The heat-sensitive recording material according to any one of (5) to (10), wherein the protective layer contains a long-chain alkyl ether-modified polyvinyl alcohol as a binder. (12) The above (1) to (1), wherein the thermosensitive recording layer contains a compound represented by the above general formula.
The heat-sensitive recording material according to any one of 1) to 1).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is characterized in that a layer constituting a thermosensitive recording material contains a compound represented by the above general formula (1). Since this compound has a hydrophobic polyethylene block and a hydrophilic polyoxyethylene block in the molecule, it has a surfactant effect. When this compound is added to the protective layer, the dynamic friction with the head is reduced, and the head is less likely to be stained. This is believed to be the lubricating effect of the compound, such as a wax. In addition, as described below, the scratch resistance and stain resistance can be improved by adding inorganic ultrafine particles to the protective layer or the light transmittance adjusting layer, while adding inorganic ultrafine particles to the light transmittance adjusting layer, The white turbidity caused by the nitrogen gas generated at the time of fixing the diazo coloring layer is deteriorated. However, such a disadvantage can be avoided by adding the compound to the light transmittance adjusting layer.

Further, when the compound is added to the heat-sensitive recording layer, the sensitivity at the time of image recording is improved. Although the mechanism is not clear, it is presumed to promote mass transfer in the heat-sensitive recording layer during image recording (heating), for example, transfer of the coupler into the microcapsules. In the case of a full-color heat-sensitive recording material, it is preferable to include it in the yellow heat-sensitive recording layer and / or the magenta heat-sensitive recording layer from the viewpoint of improving sensitivity. Further, even when added to the heat-sensitive recording layer, the white turbidity can be prevented.

In the general formula (1), x is 11 to 23.
And y is preferably an integer of 8 to 42. The ratio of x to y is preferably in the range of 6: 1 to 1: 1 from the viewpoint of lubricity. When the compound is added to the protective layer, the compound is added in an amount of 2 to 3 with respect to the binder of the protective layer.
0% by weight, preferably 5 to 20% by weight, and when added to the light transmittance adjusting layer, 20 to 200% by weight, preferably 40 to 150% by weight, based on the binder of the layer.
It is.

The method of adding the compound of the general formula (1) to a coating solution such as a heat-sensitive recording layer, a protective layer, a light transmittance adjusting layer, etc., constituting a heat-sensitive recording material is as follows. Examples include a method of adding the dispersion to the coating solution for each layer, but the method is not limited thereto.

Next, the layers constituting the heat-sensitive recording material of the present invention will be described. [Thermosensitive Recording Layer] In the present invention, as a coloring component used in the thermosensitive recording layer, conventionally known ones can be used.
In particular, those utilizing the reaction between a diazonium salt compound and a coupler, or those utilizing the reaction between an electron-donating colorless dye and an electron-accepting compound are preferable, and are obtained by reacting with a diazonium salt compound and the diazonium salt compound when heated. Examples of the compound used in the heat-sensitive recording layer containing a coloring coupler include a diazonium salt compound, a coupler that can form a dye by reacting with the diazonium salt compound, and a basic compound that promotes the reaction between the diazonium salt compound and the coupler. Substances and the like. The diazonium salt compound is a compound represented by the following, and can control the maximum absorption wavelength depending on the position and type of the substituent in the Ar portion.

(Diazonium Salt Compound) The diazonium salt compound used in the present invention is represented by the following general formulas R ₁ , R ₂ and R ₅ Ar—N ₂ ⁺ X ⁻ (wherein Ar represents an aromatic moiety and X ⁻ Represents an acid anion.), Which undergoes a coupling reaction with a coupler upon heating to form a color and is decomposed by light. These can control the maximum absorption wavelength depending on the position and type of the substituent in the Ar portion.

Specific examples of diazonium forming a salt include 4- (p-tolylthio) -2,5-dibutoxybenzenediazonium and 4- (4-chlorophenylthio)-
2,5-dibutoxybenzenediazonium, 4- (N,
N-dimethylamino) benzenediazonium, 4-
(N, N-diethylamino) benzenediazonium, 4
-(N, N-dipropylamino) benzenediazonium, 4- (N-methyl-N-benzylamino) benzenediazonium, 4- (N, N-dibenzylamino) benzenediazonium, 4- (N-ethyl-N -Hydroxyethylamino) benzenediazonium, 4- (N, N-
Diethylamino) -3-methoxybenzenediazonium, 4- (N, N-dimethylamino) -2-methoxybenzenediazonium, 4- (N-benzoylamino)-
2,5-diethoxybenzenediazonium, 4-morpholino-2,5-dibutoxybenzenediazonium, 4-
Anilinobenzenediazonium, 4- [N- (4-methoxybenzoyl) amino] -2.5-diethoxybenzenediazonium, 4-pyrrolidino-3-ethylbenzenediazonium, 4- [N- (1-methyl-2- ( 4-methoxyphenoxy) ethyl) -N-hexylamino]-
2-hexyloxybenzenediazonium, 4- [N-
(2- (4-methoxyphenoxy) ethyl) -N-hexylamino] -2-hexyloxybenzenediazonium, 2- (1-ethylpropyloxy) -4- [di-
(Di-n-butylaminocarbonylmethyl) amino] benzenediazonium, 2-benzylsulfonyl-4-
[N-methyl-N- (2-octanoyloxyethyl)] aminobenzenediazonium and the like.

The maximum absorption wavelength λ _max of the diazonium salt compound used in the present invention is preferably 450 nm or less from the viewpoint of the effect, and more preferably 290 to 440 nm. Diazonium salt compound is in terms of storability and having a lambda _max to the longer wavelength side than the wavelength range, the image fixing property in combination with the coupler to have a lambda _max in the short wavelength side, image storability, cyan forming Neither is preferred in terms of hue. The diazonium salt compound used in the present invention has 12 or more carbon atoms,
It is desirable that the solubility in water is 1% or less and the solubility in ethyl acetate is 5% or more.

[0015] Among these diazonium salt compounds,
It is more preferable to use diazonium salt compounds represented by the following structural formulas (2) to (4) in terms of the hue of the dye, image storability, and image fixability.

[0016]

Embedded image

In the structural formula (2), Ar represents a substituted or unsubstituted aryl group. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxamide group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, Examples thereof include a halogen group, an amino group, and a heterocyclic group, and these substituents may be further substituted.

The aryl group represented by Ar is preferably an aryl group having 6 to 30 carbon atoms, for example, phenyl, 2-methylphenyl, 2-chlorophenyl, 2-methoxyphenyl, 2-butoxy. Phenyl group, 2- (2-ethylhexyloxy) phenyl group, 2
-Octyloxyphenyl group, 3- (2,4-di-t-
Pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group, 2,5-dichlorophenyl group, 2,4,6
-Trimethylphenyl group, 3-chlorophenyl group, 3-
Methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2-ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group, 3,5-dichlorophenyl group, 3,4 -Dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group , 4-benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4-
(2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-
2,5-butoxyphenyl group, 4- (N-benzyl-N
-Methylamino) -2-dodecyloxycarbonylphenyl group and the like, but are not particularly limited thereto. Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.

R ¹¹ and R ¹² each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹¹ and R ¹² may be the same or different. Examples of the substituent include, but are not limited to, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonyl group, a substituted amino group, a substituted amide group, an aryl group, and an aryloxy group.

When R ¹¹ and R ¹² each represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, for example, a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, Isopropyl group, butyl group, sec-butyl group, t-butyl group, pentyl group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl group, nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group, tolphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, 2 ′, 4′-diisopentyl Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- ( 2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
And a diethylamino) propyl group.

When R ¹¹ and R ¹² each represent an aryl group, the aryl group has 6 to 3 carbon atoms.
An aryl group of 0 is preferable, for example, a phenyl group, 2-
Methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2-ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t- Pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group, 2,
5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2-ethylhexyl) An oxy) phenyl group, a 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like, but are not particularly limited thereto. Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.

In the structural formula (3), R¹⁴, R¹⁵And R
¹⁶Is a substituted or unsubstituted alkyl group, or
Represents a substituted or unsubstituted aryl group. R¹⁴, R¹⁵Passing
And R ¹⁶May be the same or different. Place
Examples of the substituent include an alkyl group, an alkoxy group and an alkyl group.
O group, aryl group, aryloxy group, arylthio
Group, acyl group, alkoxycarbonyl group, carbamoyl
Group, carboamide group, sulfonyl group, sulfamoyl
Group, sulfonamide group, ureido group, halogen atom,
Examples include a mino group and a heterocyclic group.

When R ¹⁴ , R ¹⁵ and R ¹⁶ each represent an alkyl group, the alkyl group has 1 to 1 carbon atoms.
Preferred are alkyl groups of 8, for example, methyl group, trifluoromethyl group, ethyl group, propyl group, isopropyl group, butyl group, sec-butyl group, t-butyl group, ventil group, isopentyl group, cyclopentyl group, hexyl group A cyclohexyl group, an octyl group, a t-octyl group,
2-ethylhexyl, nonyl, octadecyl, benzyl, 4-methoxybenzyl, triphenylmethyl, ethoxycarbonylmethyl, butoxycarbonylmethyl, 2-ethylhexyloxycarbonylmethyl, 2 ', 4'-di Isopentylphenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-
Di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- (2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) Ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
Diethylamino) propyl group, 1-methyl-2- (4-
(Methoxyphenoxy) ethyl group, di-n-butylaminocarbonylmethyl group, di-n-octylaminocarbonylmethyl group and the like.

When R ¹⁴ , R ¹⁵ and R ¹⁶ each represent an aryl group, the aryl group is preferably an aryl group having 6 to 30 carbon atoms, for example, a phenyl group, a 2-methylphenyl group, 2-chlorophenyl group, 2
-Methoxyphenyl group, 2-butoxyphenyl group, 2-
(2-ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group, 2,5-dichlorophenyl group, 2,4,4 6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2-ethylhexyloxy) phenyl group, 3,4- Dichlorophenyl group, 3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxy Phenyl group, 4- (2-ethylhexyloxy) phenyl group, 4-benzylphenyl Group, 4-aminosulfonylphenyl group, 4-N, N-dibutyl-aminosulfonylphenyl group, 4-ethoxycarbonyl phenyl group, 4- (2
-Ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5 −
Examples thereof include a butoxyphenyl group and a 4- (N-benzyl-N-methylamino) -2-dodecyloxycarbonylphenyl group, but are not particularly limited thereto. Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.

Y in the structural formula (3) is a hydrogen atom or -O
Represents an R ¹³ group. In the —OR ¹³ group, R ¹³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxamide group, a sulfonyl group,
Examples include a sulfamoyl group, a sulfonamide group, a ureido group, a halogen atom, an amino group, and a heterocyclic group. From the viewpoint of hue adjustment, Y is preferably a hydrogen atom or an alkyloxy group in which R ¹³ is an alkyl group.

When R ¹³ in the —OR ¹³ group represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, for example, a methyl group, a trifluoromethyl group, an ethyl group, a propyl group , Isopropyl group,
Butyl group, sec-butyl group, t-butyl group, ventil group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl group, nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group, tolphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, 2 ′, 4′-diisopentyl Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- ( 2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
And a diethylamino) propyl group.

When R ¹³ in the —OR ¹³ group represents an aryl group, the aryl group has from 6 to 7 carbon atoms.
30 aryl groups are preferred, for example a phenyl group, 2
-Methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2-
An ethylhexyloxy) phenyl group, a 2-octyloxyphenyl group, a 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, a 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2 -Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group and the like, but are not particularly limited thereto. Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.

In the structural formula (4), R ¹⁷ and R ¹⁸ are
Each represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹⁷ and R ¹⁸ may be the same or different. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxamide group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, Examples include a halogen atom, an amino group, and a heterocyclic group.

When R ¹⁷ and R ¹⁸ each represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, for example, methyl, trifluoromethyl, ethyl, propyl, isopropyl Group, butyl group, sec-butyl group, t-butyl group, pentyl group, isopentyl group, cyclopentyl group, hexyl group, cyclohexyl group, octyl group, t-octyl group, 2-ethylhexyl group, nonyl group, octadecyl group, benzyl Group,
4-methoxybenzyl group, triphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group,
2 ′, 4′-diisobentylphenyloxymethyl group,
2 ′, 4′-di-t-butylphenyloxymethyl group,
Dibenzylaminocarbonylmethyl group, 2,4-di-t
-Amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- (2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group,
-(N, N-dimethylamino) ethyl group, 2- (N, N
-Diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2- (N, N
-Dimethylamino) ethyl group, 2- (N, N-diethylamino) propyl group, and the like, but are not particularly limited thereto.

When R ¹⁷ and R ¹⁸ each represent an aryl group, the aryl group has 6 to 3 carbon atoms.
An aryl group of 0 is preferable, for example, a phenyl group, 2-
Methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2-ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t- Pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group, 2,
5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2- Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group and the like. Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, and the like.

In the structural formulas (2) to (4), X ^- is
Represents an acid anion, wherein the acid anion has 1 carbon atom
To 9 polyfluoroalkylcarboxylic acids, 1 carbon atom
To 9, polyfluoroalkylsulfonic acid, boron tetrafluoride, tetraphenylboron, hexafluorophosphoric acid, aromatic carboxylic acid, aromatic sulfonic acid and the like. Hexafluorophosphoric acid is preferred from the viewpoint of crystallinity.

The specific examples of the diazonium salt compounds represented by the structural formulas (2) to (4) are shown below, but the present invention is not limited to these.

[0033]

Embedded image

[0034]

Embedded image

[0035]

Embedded image

[0036]

Embedded image

In the present invention, the diazonium salt compounds represented by the structural formulas (2) to (4) may be used alone or in combination of two or more. Further, the diazonium salt compounds represented by the structural formulas (2) to (4) may be used in combination with an existing diazonium salt compound according to various purposes such as hue adjustment.

In the present invention, any coupler capable of forming a dye by coupling with a diazo compound can be used as long as it can form a dye by coupling with a diazo compound in a basic atmosphere and / or a neutral atmosphere. It is possible. All so-called 4-equivalent couplers for silver halide photographic materials can be used as couplers. These can be selected according to the desired hue.

For example, there are a so-called active methylene compound having a methylene group next to the carbonyl group, a phenol derivative, a naphthol derivative and the like, and specific examples thereof include the following, which can be used in a range meeting the object of the present invention.

Particularly preferred couplers usable in the present invention are compounds represented by the following formulas. E ¹ —CH ₂ —E ² Next, the coupler represented by the above formula will be described in detail.
The electron-withdrawing group represented by E ¹ or E ² in the formula is Hamme.
A substituent having a positive σ value of tt, which may be the same or different, is an acyl group, an alkoxycarbonyl group, a carbamoyl group, a cyano group, a nitro group, an alkylsulfonyl group, an arylsulfonyl group. , A heterocyclic group, a phosphono group and the like. Acetyl group, propionyl group, pivaloyl group, chloroacetyl group, trichloroacetyl group, trifluoroacetyl group, 1-methylcyclopropylcarbonyl group, 1-ethylcyclopropylcarbonyl group, 1-benzylcyclopropylcarbonyl group,
Benzoyl group, 4-methoxybenzoyl group, acyl group such as tenoyl group, methoxycarbonyl group, ethoxycarbonyl group, 2-methoxyethoxycarbonyl group, oxycarbonyl group such as 4-methoxyphenoxycarbonyl group,
Carbamoyl group, N, N-dimethylcarbamoyl group,
N, N-diethylcarbamoyl group, N-phenylcarbamoyl group, N- [2,4-bis (pentyloxy) phenyl] carbamoyl group, N- [2,4-bis (octyloxy) phenyl] carbamoyl group, morpholinocarbonyl Carbamoyl group, methanesulfonyl group, benzenesulfonyl group, alkylsulfonyl group or arylsulfonyl group such as toluenesulfonyl group, phosphono group such as diethylphosphono group, benzoxazol-2-yl group, benzothiazol-2-yl And heterocyclic groups such as 3,4-dihydroquinazolin-4-one-2-yl group and 3,4-dihydroquinazolin-4-sulfon-2-yl group, nitro group, imino group and cyano group.

The electron-withdrawing groups represented by E ¹ and E ² may be combined with each other to form a ring. The ring formed by E ¹ and E ² is preferably a 5- or 6-membered carbon ring or heterocyclic ring.

Specific examples include resorcin, phloroglucin, 2,3-dihydroxynaphthalene, sodium 2,3-dihydroxynaphthalene-6-sulfonate,
-Hydroxy-2-naphthoic acid morpholinopropylamide, sodium 2-hydroxy-3-naphthalenesulfonate, 2-hydroxy-3-naphthalenesulfonic acid anilide, 2-hydroxy-3-naphthalenesulfonic acid morpholinopropylamide, 2-hydroxy- 3-naphthalenesulfonic acid-2-ethylhexyloxypropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-
Ethylhexylamide, 5-acetamido-1-naphthol, 1-hydroxy-8-acetamidonaphthalene-
Sodium 3,6-disulfonate, 1-hydroxy-8
-Acetamidonaphthalene-3,6-disulfonic acid dianilide, 1,5-dihydroxynaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-
Hydroxy-3-naphthoic acid octylamide, 2-hydroxy-3-naphthoic acid anilide, 5,5-dimethyl-
1,3-cyclohexanedione, 1,3-cyclopentanedione, 5- (2-n-tetradecyloxyphenyl) -1,3-cyclohexanedione, 5-phenyl-
4-methoxycarbonyl-1,3-cyclohexanedione, 5- (2,5-di-n-octyloxyphenyl)
-1,3-cyclohexanedione, N, N'-dicyclohexylbarbituric acid, N, N'-di-n-dodecylbarbituric acid, Nn-octyl-N'-n-octadecyl barbituric acid, N- Phenyl-N '-(2,5
-Di-n-octyloxyphenyl) barbituric acid,
N, N'-bis (octadecyloxycarbonylmethyl) barbituric acid, 1-phenyl-3-methyl-5-
Pyrazolone, 1- (2,4,6-trichlorophenyl)
-3-anilino-5-pyrazolone, 1- (2,4,6-
Trichlorophenyl) -3-benzamido-5-pyrazolone, 6-hydroxy-4-methyl-3-cyano-1-
(2-ethylhexyl) -2-pyridone, 2,4-bis- (benzoylacetamido) toluene, 1,3-bis- (pivaloylacetoamidomethyl) benzene, benzoylacetonitrile, thenoylacetonitrile, acetoacetanilide, benzoylacetanilide, Pivaloylacetoanilide, 2-chloro-5- (Nn-butylsulfamoyl) -1-pivaloylacetamidobenzene, 1- (2-ethylhexyloxypropyl) -3-
Cyano-4-methyl-6-hydroxy-1,2-dihydropyridin-2-one, 1- (dodecyloxypropyl) -3-acetyl-4-methyl-6-hydroxy-
1,2-dihydropyridin-2-one, 1- (4-n-
Octyloxyphenyl) -3-tert-butyl-5
-Aminopyrazole and the like. For details of the coupler, see JP-A-4-201483 and JP-A-7-2233.
No. 67, JP-A-7-223368, JP-A-7-323
No. 660, Japanese Patent Application No. 5-278608, Japanese Patent Application No. 5-29
7024, Japanese Patent Application No. 6-18669, Japanese Patent Application No. 6-18
No. 670, Japanese Patent Application No. 7-316280, Japanese Patent Application No. 8-02
No. 7095, Japanese Patent Application No. 8-027096, Japanese Patent Application No. 8-0
No. 30799, Japanese Patent Application No. 8-12610, Japanese Patent Application No. 8-1
No. 32394, Japanese Patent Application No. 8-358755, Japanese Patent Application No. 8-
358756 and Japanese Patent Application No. 9-069990.

Specific examples of the coupler represented by the above formula of the present invention are shown below, but the present invention is not limited thereto.

[0044]

Embedded image

[0045]

Embedded image

[0046]

Embedded image

[0047]

Embedded image

The electron-donating dye precursor used in the heat-sensitive recording layer of the present invention includes triarylmethane compounds, diphenylmethane compounds, thiazine compounds, xanthene compounds, spiropyran compounds, and the like. Methane compounds and xanthene compounds are useful because of their high color density. Examples of some of these are 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (that is, crystal violet lactone), 3,3-bis (p-dimethylamino) phthalide, (P-dimethylaminophenyl) -3- (1,3-dimethylindol-3-yl) phthalide, 3- (p-dimethylaminophenyl)-
3- (2-methylindol-3-yl) phthalide, 3
-(O-methyl-p-diethylaminophenyl) -3-
(2-methylindol-3-yl) phthalide, 4,
4'-bis (dimethylamino) benzhydrin benzyl ether, N-halophenylleuco auramine, N-
2,4,5-trichlorophenylleuco auramine, rhodamine-B-anilinolactam, rhodamine (p-nitroanilino) lactam, rhodamine-B- (p-chloroanilino) lactam, 2-benzylamino-6-diethylaminofluoran, 2-anilino-6-diethylaminofluoran, 2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6
-Cyclohexylmethylaminofluoran, 2-anilino-3-methyl-6-isoamylethylaminofluoran, 2- (o-chloroanilino) -6-diethylaminofluoran, 2-octylamino-6-diethylaminofluoran, 2- Ethoxyethylamino-3-chloro-
2-diethylaminofluoran, 2-anilino-3-chloro-6-diethylaminofluoran, benzoylleucomethylene blue, p-nitrobenzylleucomethylene blue, 3-methyl-spiro-dinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3,3 '-Dichloro-
Spiro-dinaphthopyran, 3-benzylspirodinaphthopyran, 3-propyl-spiro-dibenzopyran and the like can be mentioned.

Examples of the electron-accepting compound include phenol derivatives, salicylic acid derivatives, and hydroxybenzoic acid esters. Particularly, bisphenols and hydroxybenzoates are preferred. Some examples of these include 2,2-bis (p-hydroxyphenyl) propane (ie, bisphenol A), 4,4 ′-(p-phenylenediisopropylidene) diphenol (ie, bisphenol P), 2,2-bis (p-hydroxyphenyl) pentane, 2,2-bis (p-hydroxyphenyl) ethane, 2,2-bis (p-hydroxyphenyl)
Butane, 2,2-bis (4'-hydroxy-3 ', 5'
-Dichlorophenyl) propane, 1,1- (p-hydroxyphenyl) cyclohexane, 1,1- (p-hydroxyphenyl) propane, 1,1- (p-hydroxyphenyl) pentane, 1,1- (p-hydroxyphenyl) ) -2-Ethylhexane, 3,5-di (α-methylbenzyl) salicylic acid and its polyvalent metal salts, 3,5-di (tert-butyl) salicylic acid and its polyvalent metal salts, 3-α, α- Dimethylbenzyl salicylic acid and its polyvalent metal salts, butyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, p-hydroxybenzoic acid
2-ethylhexyl, p-phenylphenol, p-cumylphenol and the like can be mentioned.

As the sensitizer, a low-melting organic compound having an appropriate aromatic group and polar group in the molecule is preferable, and benzyl p-benzyloxybenzoate, α-naphthyl benzyl ether, β- Naphthyl benzyl ether,
β-naphthoic acid phenyl ester, α-hydroxy-β
-Naphthoic acid phenyl ester, β-naphthol- (p
-Chlorobenzyl) ether, 1,4-butanediol phenyl ether, 1,4-butanediol-p-methylphenyl ether, 1,4-butanediol-p-ethylphenyl ether, 1,4-butanediol-m-
Methyl phenyl ether, 1-phenoxy-2- (p-
Tolyloxy) ethane, 1-phenoxy-2- (p-ethylphenoxy) ethane, 1-phenoxy-2- (p-
Chlorophenoxy) ethane, p-benzylbiphenyl and the like.

In the present invention, use forms of the above-mentioned diazonium salt compound, a coupler, a basic substance, a colorless electron-donating dye, an electron-accepting compound, and a sensitizer which react with the diazonium salt compound to give a color when heated. Is not particularly limited. That is, (1) a method of using a solid dispersion, (2) a method of using an emulsified dispersion, (3) a method of using a polymer dispersed, (4) a method of using a latex dispersed, and (5) a micro method. Although there is a method of encapsulation and the like, among them, the method of microencapsulation is particularly preferable from the viewpoint of storage stability, and particularly in a color forming system utilizing a reaction between a diazonium salt compound and a coupler, a diazonium salt compound is used. In the case of microencapsulation, it is preferable to microencapsulate the electron donating colorless dye in a color forming system utilizing the reaction between the electron donating colorless dye and the electron accepting compound.

As a method of microencapsulation, a conventionally known microcapsule method can be used.
That is, the colorant, additives and the microcapsule wall precursor are dissolved in an organic solvent that is hardly soluble or insoluble in water, added to an aqueous solution of a water-soluble polymer, emulsified and dispersed using a homogenizer or the like, and heated. Thus, it can be adjusted by forming a polymer substance to be a microcapsule wall as a wall film at the oil / water interface.

Examples of the organic solvent include low-boiling auxiliary solvents such as acetate, methylene chloride and cyclohexanone and / or phosphates, phthalates, acrylates, methacrylates, other carboxylic esters, fatty acid amides, and the like. Alkylated biphenyl, alkylated terphenyl, alkylated naphthalene,
Diarylethane, chlorinated paraffin, alcoholic,
Phenol type, ether type, monoolefin type, epoxy type and the like can be mentioned. Specific examples include tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, tricyclohexyl phosphate, dibutyl phthalate, dioctyl phthalate, dilaurate phthalate, dicyclohexyl phthalate, butyl olefin, diethylene glycol benzoate, dioctyl sebacate, Dibutyl sebacate, dioctyl adipate, trioctyl trimellitate, acetyl triethyl citrate, octyl maleate, dibutyl maleate, isoamyl biphenyl, chlorinated paraffin, diisopropyl naphthalene,
1,1'-ditolylethane, 2,4-ditertiaryamylphenol, N, N-dibutyl-2-butoxy-5
Tert-octylaniline, hydroxybenzoic acid 2-
Ethylhexyl ester, high-boiling oils such as polyethylene glycol, and among them, alcohols, phosphates, carboxylic esters,
Preferred are alkylated biphenyls, alkylated terphenyls, alkylated naphthalenes, and diarylethanes. Further, an anti-carbonizing agent such as hindered phenol and hindered amine may be added to the high boiling point oil. Further, as the oil, those having an unsaturated fatty acid are particularly desirable,
α-methylstyrene dimer and the like.
Examples of the α-methylstyrene dimer include “MSD100” (trade name, manufactured by Mitsui Toatsu Chemicals, Inc.).

As the water-soluble polymer, a water-soluble polymer such as polyvinyl alcohol is used, but an emulsion or latex of a hydrophobic polymer may be used in combination. As the water-soluble polymer, polyvinyl alcohol,
Silanol-modified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, amino-modified polyvinyl alcohol, itaconic acid-modified polyvinyl alcohol, styrene
Maleic anhydride copolymer, butadiene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylamide, polystyrenesulfonic acid, polyvinylpyrrolidone,
Examples thereof include an ethylene-acrylic acid copolymer and gelatin. Among them, carboxy-modified polyvinyl alcohol is particularly preferable. As the emulsion or latex of the hydrophobic polymer, a styrene-butadiene copolymer,
Examples thereof include carboxy-modified styrene-butadiene copolymer and acrylonitrile-butadiene copolymer. At this time, a conventionally known surfactant or the like may be added as necessary. Specific examples of the polymer substance serving as the wall film of the microcapsule include, for example, polyurethane resin, polyurea resin,
Examples include polyamide resin, polyester resin, polycarbonate resin, aminoaldehyde resin, melamine resin, polystyrene resin, styrene-acrylate copolymer resin, styrene-methacrylate copolymer resin, gelatin, and polyvinyl alcohol. Among these, a particularly preferred wall agent is a polyurethane / polyurea resin. Microcapsules having a wall film made of polyurethane / polyurea resin, a microcapsule wall precursor such as polyvalent isocyanate is mixed in a core material to be encapsulated, and emulsified and dispersed in an aqueous solution of a water-soluble polymer such as polyvinyl alcohol. It is produced by raising the liquid temperature and causing a polymer forming reaction at the oil droplet interface.

Here, some specific examples of the polyvalent isocyanate compound are shown below. For example, m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-
Tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4′-diisocyanate, 3,
3'-diphenylmethane-4,4'-diisocyanate, xylene-1,4-diisocyanate, 4,4'-
Diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, butylene-1,
Diisocyanates such as 2-diisocyanate, cyclohexylene-1,2-diisocyanate, and cyclohexylene-1,4-diisocyanate; 4,4 ′, 4 ″-
Triphenylmethane triisocyanate, toluene
Triisocyanates such as 2,4,6-triisocyanate, 4,4′-dimethylphenylmethane-2,2 ′,
Tetraisocyanates such as 5,5'-tetraisocyanate, adducts of hexamethylene diisocyanate with trimethylolpropane, adducts of 2,4-tolylenediisocyanate with trimethylolpropane, and xylylenediisocyanate with trimethylolpropane Isocyanate prepolymers such as adducts and adducts of tolylene diisocyanate and hexanetriol, and the like. If necessary, two or more kinds can be used in combination. Of these, particularly preferred are those having three or more isocyanate groups in the molecule.

In the microencapsulation method, the oil shown by emulsification and dispersion can be used as the organic solvent for dissolving the colorant, additives and microcapsule wall precursor. The same applies to a water-soluble polymer.
The particle size of the microcapsules is preferably from 0.1 to 1.0 μm, more preferably from 0.2 to 0.7 μm.

The heat-sensitive recording material of the present invention may be provided with one or a plurality of heat-sensitive recording layers. If you have more than one,
It is necessary to use coloring agents having different energies required for coloring. Further, the heat-sensitive recording material of the present invention may be full-color or monocolor, but is mainly composed of a diazo compound on a support, a diazo-based coloring agent containing a coupler that reacts with the diazo compound, and a binder. What has at least one thermosensitive recording layer (light fixing type thermosensitive recording layer) is desirable. For example, a light-fixing type heat-sensitive recording layer comprises a heat-sensitive recording layer containing a diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm and a coupler which reacts with the diazonium salt compound to form a color.
A heat-sensitive recording layer containing a diazonium salt compound having a diameter of 0 ± 20 nm and a photo-fixing heat-sensitive recording layer containing a coupler which reacts with the diazonium salt compound to form a color is preferably used.

In the case of a full-color thermosensitive recording layer containing cyan, yellow and magenta, all three layers are formed of a diazo-based coloring agent, or the first thermosensitive recording layer close to the support has an electron-donating dye and an electron-donating dye. It is preferable that the thermosensitive recording layer is formed of a leuco-based coloring agent containing a receptive compound and the second and third heat-sensitive recording layers are formed of a diazo-based coloring agent.

When all three layers are composed of a diazo-based coloring agent, the maximum absorption wavelength is, for example, 340 ± 20 nm on a support.
A light-fixing first heat-sensitive recording layer containing the following diazonium salt compound and a coupler that undergoes a color reaction with the diazonium salt compound, a diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm, and the diazonium salt compound A second heat-sensitive recording layer of a photo-fixing type containing a coupler which reacts with and forms a color, a diazonium salt compound having a maximum absorption wavelength of 400 ± 20 nm, and a coupler which reacts with the diazonium salt compound to form a color. One provided with a light-fixing third heat-sensitive recording layer is preferred.

When a leuco coloring agent is used in the first layer, for example, a first heat-sensitive recording layer containing an electron-donating dye and an electron-accepting compound, a support having a maximum absorption wavelength of 360 ± A light fixing type second heat-sensitive recording layer containing a diazonium salt compound having a thickness of 20 nm and a coupler which reacts with the diazonium salt compound to form a color;
A heat-sensitive recording layer provided with a light-fixing third heat-sensitive recording layer containing a diazonium salt compound having a diameter of ± 20 nm and a coupler that reacts with the diazonium salt compound to form a color is preferably used.

Further, in each of the above thermosensitive recording materials,
It is desirable to provide a light transmittance adjusting layer and a protective layer on the heat-sensitive recording layer.

In the method for recording a heat-sensitive recording material comprising a plurality of heat-sensitive recording layers of a diazo-based color former, the third heat-sensitive recording layer is first heated to develop the color of the diazonium salt compound and the coupler contained in the layer. Next, after irradiating light having the maximum absorption wavelength of the diazonium salt compound to decompose unreacted diazonium salt compounds contained in the third thermosensitive recording layer, the second thermosensitive recording layer develops color. Is applied sufficiently to develop the color of the diazonium salt compound and the coupler contained in the layer. At this time, the third heat-sensitive recording layer is also heated strongly, but does not develop color because the diazonium salt compound has already been decomposed and the color-forming ability has been lost. Furthermore, the diazonium salt compound contained in the second heat-sensitive recording layer is decomposed by irradiating light having the maximum absorption wavelength of the diazonium salt compound, and finally, sufficient heat is applied to cause the first heat-sensitive recording layer to develop color. Color. At this time, the third and second heat-sensitive recording layers are also heated strongly, but the diazonium salt compound has already been decomposed and the color-forming ability has been lost, so that no color is formed. The fixing treatment for the diazonium salt compound in the third layer can be omitted. Also, when the third layer is a leuco-based coloring agent, the other two layers of the thermosensitive recording layer containing the diazo-based coloring agent are similarly colored and fixed, and finally, the layer containing the leuco-based coloring agent is heated to form a color. Let it.

[Protective Layer] The protective layer can contain a pigment, a lubricant, a surfactant, a dispersant, a fluorescent brightener, a metal soap, a hardener, an ultraviolet absorber, a crosslinking agent, and the like, together with a binder. In the heat-sensitive recording material of the present invention, it is preferable to add the compound represented by the general formula (1) to the protective layer, whereby the effect of reducing the dynamic friction with the head and making the head less likely to be stained is obtained. Can be As the binder, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, starch, gelatin, gum arabic,
Casein, styrene-maleic anhydride copolymer hydrolysate, ethylene-maleic anhydride copolymer hydrolysate, isobutylene-maleic anhydride copolymer hydrolysate, polyvinyl alcohol, modified polyvinyl alcohol, polyacrylamide, etc. It can be appropriately selected and used within a range that does not impair the barrier property and the workability. When a long-chain alkyl ether-modified polyvinyl alcohol represented by the following formula (A) having a hydrophobic portion in the molecule is used as the binder, the compatibility with the compound of the present invention represented by the general formula is excellent. This is effective in suppressing gloss unevenness. In addition, the long-chain alkyl group is easily oriented on the surface of the protective layer using the long-chain alkyl ether-modified polyvinyl alcohol, which reduces the dynamic friction of the thermal head, eliminates printing failure, and reduces the smoothness (gloss ), And the color density can be improved.

[0064]

Embedded image

(Wherein R¹Is a hydrogen atom, a methyl group,
Is -CH_TwoCO_TwoM, R^TwoIs a hydrogen atom, or-
CO_TwoM, R^ThreeIs a hydrogen atom, -CO_TwoM, amino
Group, amide group, substituted amide group, hydroxy group, glycidyl
Group, sulfonic acid group, polyethylene oxide group, poly
Propylene oxide group or having these functional groups
Represents a group represented by^FourRepresents a hydrogen atom or a methyl group. R
¹, R^Two, R^FourIs a hydrogen atom and R^ThreeIs -CO_TwoSet of M
Combined or R^Two, R^FourIs a hydrogen atom and R ¹Is -C
H_TwoCO_TwoM and R^ThreeIs -CO_TwoM combination preferred
No. M is a hydrogen atom, an alkyl group, an aryl group,
Represents a alkyl group, Na, K, or Li. R^FiveIs a long chain
Alkyl group, that is, an alkyl group having 8 to 20 carbon atoms.
You. Alkyl groups may be straight-chain or branched, and
And it may have a substituent such as a hydroxyl group. Among them, carbon
Alkyl groups of several 8 to 16 are more preferable in terms of lubricity,
A dodecyl group having 12 carbon atoms is particularly preferred. n, x,
y and z each represent a degree of polymerization. n is preferably 0 to 20
And 0 to 10 are more preferable. When the value of n is large
The acid group has an increased acidic group, and the compatibility with gelatin is improved. T
g (glass transition point) or lower gas barrier properties
X can be used to bring out the properties of alcohol
60-99 is preferred, and 75-95 is more preferred. y
Is preferably 0 to 20. z is abrasion resistance with the thermal recording head
Larger is preferable in terms of friction and lubricity, but solubility and water
There is a limit in terms of solution viscosity, and the sum of n, x, y, and z
On the other hand, a value of 0.5 to 10% is preferable, and more preferable.
1 to 5%.

The long chain alkyl ether-modified polyvinyl alcohol has a Tg of 50 ° C. or more, preferably 60 ° C. or more. If the Tg (glass transition point) is less than 50 ° C., the scratch resistance decreases, which is not preferable.

Examples of other binders include synthetic rubber latex and synthetic resin emulsion, such as styrene butadiene rubber latex, acrylonitrile-butadiene rubber latex, methyl acrylate-butadiene rubber latex, and vinyl acetate emulsion. . The binder is used in an amount of 10 to 500% by weight, preferably 50 to 400% by weight, based on the pigment contained in the protective layer.

Further, in order to further improve the water resistance, it is effective to use a crosslinking agent and a catalyst for accelerating the reaction.
Specific examples of the crosslinking agent include an epoxy compound, a blocked isocyanate, a vinyl sulfone compound, an aldehyde compound, a methylol compound, boric acid, a carboxylic anhydride, a silane compound, a chelate compound, and a halide. Preferably, the pH can be adjusted to 6.0 to 7.5. As the catalyst, known catalysts such as acids and metal salts can be used.
Those that can be adjusted to 7.5 are preferred.

As the pigment that can be used in the protective layer of the present invention, all general organic or inorganic pigments can be used.
The pigment improves the rub resistance and lubricity of the protective layer. Specifically, calcium carbonate, aluminum hydroxide, barium sulfate, titanium oxide, talc, wax, kaolin, calcined kaolin, amorphous silica, aluminum oxide, zinc oxide, zirconium oxide, urea formalin resin powder, polyethylene resin powder, Benzoguanamine resin powder and the like can be mentioned. These are used alone or in combination of two or more.

In the present invention, the average primary particle size is 0.1.
It is preferable to add inorganic ultrafine particles of 1 μm or less to the protective layer. In the present invention, the inorganic ultrafine particles refer to inorganic fine particles having an average primary particle size of 0.1 μm or less, and are not particularly limited as long as the average primary particle size is 0.1 μm. The threshold value at the larger particle size distribution in the liquid is preferably 0.5 μm or less, more preferably 0.4 μm or less, and particularly preferably 0.3 μm or less. The frequency of (agglomerated) particles having a particle diameter of 0.35 μm or more in the dispersion is 5% or less, preferably 1% or less, and 0.25 μm or less.
It is particularly preferable that the frequency of (aggregated) particles of m or more is 5% or less. The particle size is determined by a known method, for example, COU
LTER N4 type submicron particle size analyzer (Nikkaki)
It can be measured by, for example,

The inorganic ultrafine particles used in the present invention include:
Barium sulfate, zinc oxide, magnesium oxide, lead oxide,
Inorganic ultrafine particles of zirconium oxide, colloidal silica or alumina are preferred, and barium sulfate, colloidal silica and alumina are more preferred. Among them, barium sulfate and zirconium oxide are particularly preferred.

The above-mentioned inorganic ultrafine particles may be used alone or in combination of two or more. In particular, colloidal silica has a high activity, and when performing multi-layer simultaneous coating, depending on the combination, coating unevenness may occur due to interaction with a compound of another layer, and the surface smoothness of the obtained heat-sensitive recording material may be impaired. Therefore, when using colloidal silica, it is preferable to use colloidal silica and other inorganic ultrafine particles in combination, and the mixing ratio (colloidal silica / other inorganic ultrafine particles) is 1/9 to 6/4 by weight. Is preferred, and a blending ratio of 2/8 to 5/5 is more preferred. As the combination of the inorganic ultrafine particles to be used together, a combination of colloidal silica and barium sulfate is preferable, and it is more preferable to use colloidal silica and barium sulfate in a mixing ratio of 2/8 to 5/5.

As the inorganic ultrafine particles having an average particle diameter of 0.1 μm or less which can be suitably used in the present invention, for example, those shown in Table 1 are commercially available.

[0074]

[Table 1]

In the present invention, the amount of the inorganic ultrafine particles to be added to the protective layer is 0.01 to 1 g / m ² , and 1 to 100 g / m ² with respect to the binder (including the silicone-modified polymer).
% By weight, preferably 5 to 50% by weight. 0.01g
/ M less than ² and the effect of adding the inorganic ultrafine particles is insufficient, there is a case where glossiness exceeds 1 g / m ² is reduced.

As a method of blending the inorganic ultrafine particles with the coating solution for forming the protective layer of the present invention, in order to prevent aggregation of the fine particles and to achieve uniform adsorption on the surface of the resin particles, Carboxymethylcellulose, gelatin, a method of blending as a resin solution with an aqueous dispersion resin such as polyvinyl alcohol, a method of blending after preparing a colloidal dispersion with various mills and the like, and the like, are preferred from the viewpoint of effects and production. . By adding the inorganic ultrafine particles as described above to the protective layer, it is possible to prevent head contamination and improve scratch resistance.

As the lubricant, zinc stearate, calcium stearate, paraffin wax, polyethylene wax and the like are preferably exemplified. As the surfactant, a sulfosuccinic acid-based alkali metal salt, a fluorine-containing surfactant and the like are preferably used in order to uniformly form a protective layer on the heat-sensitive recording layer.
Examples include sodium salts such as (2-ethylhexyl) sulfosuccinic acid, di- (n-hexyl) sulfosuccinic acid, and ammonium salts.

The coating liquid for a protective layer of the present invention is obtained by mixing the above components. Further, a release agent, a wax, a water repellent and the like may be added as needed. The obtained protective layer coating solution is coated on the thermosensitive coloring layer using a bar coater, an air knife coater, a blade coater, a curtain coater, or the like,
Dry to obtain the protective layer of the present invention. However, the protective layer may be applied simultaneously with the color-forming layer, or after the heat-sensitive color-forming layer is applied, the heat-sensitive color-forming layer may be dried once and then applied thereon. Dry coating amount of the protective layer is preferably 0.2~7g / m ^2, more preferably from 1 to 4 g / m ^2. When the coating amount is large, the thermal sensitivity is remarkably reduced, and when the coating amount is too low, the scratch resistance and gloss cannot be maintained.
After applying the protective layer, a calendering treatment may be performed if necessary.

[Light Transmittance Adjusting Layer] The light transmittance adjusting layer contains a component that functions as a precursor of an ultraviolet absorber, and functions as an ultraviolet absorber before irradiation with light having a wavelength necessary for fixing. When fixing the light-fixing type thermosensitive recording layer, the wavelength of the area required for fixing is sufficiently transmitted, and the transmittance of visible light is high, which hinders the fixing of the thermosensitive recording layer. Does not occur. It is preferable that the precursor of the ultraviolet absorber is contained in a microcapsule. In the present invention, compounds described in JP-A-9-1928 can be used as the compound contained in the light transmittance adjusting layer. In the heat-sensitive recording material of the present invention, it is preferable to add the compound represented by the general formula (1) to the light transmittance adjusting layer. And the effect of reducing dirt on the head is obtained.

The precursor of the ultraviolet absorber is converted into an ultraviolet absorber by reacting with light or heat after light irradiation of a wavelength necessary for fixing the light fixing type thermosensitive recording layer by light irradiation is completed. As a result, most of the light in the wavelength range necessary for fixing in the ultraviolet region is absorbed by the ultraviolet absorber, the transmittance is reduced, and the light resistance of the heat-sensitive recording material is improved. Because there is no absorption effect,
The visible light transmittance is not substantially changed. At least one light transmittance adjusting layer can be provided in the light fixing type thermosensitive recording material. Most preferably, the light transmittance adjusting layer is formed between the light fixing type thermosensitive recording layer and the outermost protective layer. The adjustment layer may also serve as the protective layer. The characteristics of the light transmittance adjusting layer can be arbitrarily selected according to the characteristics of the light fixing type thermosensitive recording layer. Further, by adding the inorganic ultrafine particles to be added to the protective layer to the light transmittance adjusting layer, it is possible to further prevent head contamination and further improve the scratch resistance. In this case, the white turbidity caused by the nitrogen gas generated at the time of fixing the diazo coloring layer is deteriorated. However, such white turbidity can be prevented by adding the compound of the general formula (1) to the light transmittance adjusting layer. It is possible to

[Intermediate Layer] When a plurality of heat-sensitive recording layers are provided, it is preferable to provide an intermediate layer between the heat-sensitive recording layers. In the intermediate layer, similarly to the protective layer, various binders may further contain pigments, lubricants, surfactants, dispersants, fluorescent brighteners, metal soaps, ultraviolet absorbers, and the like. As the binder, those similar to the binder used for the protective layer can be used.

[Support] In the heat-sensitive recording material of the present invention,
As a support, polyethylene terephthalate (PE
T), polyethylene naphthalate (PEN) triacetyl cellulose (TAC), paper, plastic resin laminated paper, synthetic paper, and the like. Further, in order to obtain a transparent thermosensitive recording material, it is necessary to use a transparent support. Examples of the transparent support include a synthetic polymer film such as a polyester film such as polyethylene terephthalate or polybutylene terephthalate, a cellulose triacetate film, or a polyolefin film such as polypropylene or polyethylene.These may be used alone or in combination. Can be. The thickness of the synthetic polymer film is preferably from 25 to 250 μm, more preferably from 50 to 200 μm.

The synthetic polymer film may be colored in an arbitrary hue. As a method for coloring a polymer film, a method of kneading a resin with a dye before forming the film into a film, and then forming a film, preparing a coating solution in which the dye is dissolved in an appropriate solvent, and then preparing a transparent colorless resin film Examples of the method include a method of coating and drying by a known coating method such as a gravure coating method, a roller coating method, and a wire coating method. Above all, a polyester resin such as polyethylene terephthalate or polyethylene naphthalate in which a blue dye is kneaded is formed into a film, which is preferably subjected to a heat treatment, a stretching treatment and an antistatic treatment.

The heat-sensitive recording layer, the protective layer, the intermediate layer, the anti-reflection layer, the light-blocking layer, the undercoat layer, the back coat layer and the like are formed on a support by a blade coating method, an air knife coating method, a gravure coating method, or a roll coating method. The coating is performed by a known coating method such as a coating method, a spray coating method, a dip coating method, and a bar coating method.

In the present invention, the following known antioxidants can be used in order to further improve the light resistance. For example, European Patent Publication No.
German Patent No. 3435443, European Patent No. 310552, JP-A-3-121449
JP-A-59-41616, JP-A-2-262654, JP-A-2-71262, JP-A-63-163351, U.S. Pat. No. 4,814,262, JP-A-54-48535 ,
JP-A-5-61166, JP-A-5-119449
No., US Pat. No. 4,980,275, JP-A-63
JP-A-113536, JP-A-62-262047, EP-A-223239, EP-A-309402, and EP-A-309401.
Specific examples include the following.

[0086]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.
In addition, "part" in an Example shows all weight parts. Example 1 Example 1 (1) Preparation of Support A wood pulp consisting of 100 parts of LBKP was subjected to a Canadian freeness of 300 cc by a double disc refiner.
Beated until 0.5 parts of epoxidized behenamide, 1.0 part of anionic polyacrylamide, 0.1 part of polyamide polyamine epichlorohydrin, and 0.5 part of cationic polyacrylamide were added at an absolute dry weight ratio to pulp, A base paper having a basis weight of 100 g / m ² is formed by a fourdrinier paper machine, the surface size of polyvinyl alcohol is set to an absolute dry weight of 1.0 g / m ² , and a density of 1.0 is obtained by calendering.
Was adjusted.

After performing a corona discharge treatment on the wire surface (back surface) side of the base paper, high-density polyethylene was coated to a resin thickness of 30 μm using a melt extruder to form a resin layer having a matte surface ( This surface is called the back surface). After a corona discharge treatment on the polyethylene-coated surface of the back surface, aluminum oxide (manufactured by Nissan Chemical Industries, Ltd .; "Alumina Sol 100") / silicon dioxide (manufactured by Nissan Chemical Industries, Ltd .; "Snowtex O") as an antistatic agent ") =
1/2 (weight ratio) is dispersed in water and the weight after drying is 0.1.
2 g / m ^{2 was} applied. (This is called back PE lami product)

Further, a corona discharge treatment is applied to the felt surface (front surface) side of the base paper, and a low-density polyethylene containing 10% by weight of titanium dioxide and a small amount of ultramarine is made to have a resin thickness of 40 μm using a melt extruder. Melt extrusion coating was performed to form a resin layer having a glossy surface (this surface is referred to as a front surface). After the corona discharge treatment on the front side of the polyethylene-coated surface, the gelatin undercoat was dried at a weight of 0.1%.
g / m ² .

(2) Preparation of Undercoat Layer Liquid Swellable synthetic mica “ME100” (manufactured by Corp Chemical Co., Ltd.)
97.5 parts by weight of water was added to 2.5 parts by weight, and the mixture was dispersed with a dynamill. This was added to 200 g of a 5% by weight aqueous solution of gelatin at 40 ° C., stirred for 30 minutes, and 20 cc of the following surfactant-1 (5% by weight) was added to prepare an undercoat layer solution.

[0090]

Embedded image

(3) Preparation of Cyan Thermosensitive Recording Layer Solution <Preparation of Capsule Solution Containing Electron Donating Dye Precursor> Solution A Solution 3- (o-methyl-p-dimethylaminophenyl) -3
5 parts of-(1'-ethyl-2'-methylindol-3-yl) phthalide (electron-donating dye precursor) is dissolved in 20 parts of ethyl acetate, and 20 parts of alkylnaphthalene (high boiling point solvent) is added thereto. Add and heat to mix evenly.
To the obtained solution, 20 parts of a 1/3 adduct of xylylene diisocyanate / trimethylolpropane was added, and the mixture was stirred uniformly to prepare solution A. Solution B Liquid B was prepared by adding 2 parts by weight of a 2% by weight aqueous solution of sodium dodecyl sulfonate to 54 parts of a 6% by weight aqueous solution of phthalated gelatin.

Liquid A was added to liquid B and emulsified and dispersed using a homogenizer to obtain an emulsified dispersion. 68 parts of water is added to the obtained emulsified dispersion, mixed and homogenized, and then the mixture is heated to 50 ° C. while stirring to encapsulate the microcapsules so that the average particle diameter of the microcapsules becomes 1.2 μm. The reaction was performed for 3 hours to obtain a capsule liquid.

<Preparation of developer emulsified dispersion> 1,1- (p
-Hydroxyphenyl) -2-ethylhexane (developer) 2.5 parts, tricresyl phosphate 0.3 part and diethyl maleate 0.1 part were dissolved in ethyl acetate 10 parts. The obtained solution was added to a solution obtained by mixing 20 parts of a 6% by weight aqueous solution of gelatin and 2 parts of a 2% by weight aqueous solution of sodium dodecylsulfonate, and emulsified for 10 minutes using a homogenizer to obtain an emulsified dispersion. .

<Preparation of Coating Solution> SBR latex (manufactured by Sumitomo Nogatack; "SN-307") was added to the capsule solution containing the electron donating dye precursor prepared above at 40% by weight based on the solid content of the capsule. Thereafter, the developer emulsified dispersion was mixed with the capsule liquid containing the electron-donating dye precursor so that the weight ratio became 1/4 to obtain a coating liquid for cyan layer.

(4) Preparation of magenta thermosensitive recording layer solution <Preparation of capsule solution containing diazo compound> 2.0 parts of diazo compound (1) represented by the following structural formula (decomposed by light having a wavelength of 365 nm) was dissolved in acetic acid. After dissolving in 20 parts of ethyl,
Further, 20 parts of alkylnaphthalene was added, and the mixture was heated and uniformly mixed. To the obtained solution, 15 parts of an adduct (capsule wall material) of xylylene diisocyanate / trimethylolpropane 1/3 was added and mixed uniformly to obtain a diazo compound solution. The obtained solution of the diazo compound was added to a solution obtained by mixing 54 parts of a 6% by weight aqueous solution of phthalated gelatin and 2 parts of a 2% by weight aqueous solution of sodium dodecyl sulfonate, and emulsified and dispersed using a homogenizer. 68 parts of water was added to the obtained emulsified dispersion, mixed uniformly, and heated to 40 ° C. with stirring, so that the average particle diameter of the capsule was 1.2 μm.
The encapsulation reaction was performed for 3 hours to obtain a capsule solution.

[0096]

Embedded image

<Preparation of Coupler Emulsion Dispersion> 2 parts of coupler (1) represented by the following structural formula, 2 parts of 1,2,3-triphenylguanidine, 0.3 part of tricresyl phosphate
Parts and 0.1 part of diethyl maleate were dissolved in 10 parts of ethyl acetate. The obtained solution is poured into an aqueous solution obtained by mixing 20 parts of a 6% by weight aqueous solution of gelatin and 2 parts of an aqueous solution of 2% by weight of sodium dodecyl sulfonate, and then emulsified for 10 minutes using a homogenizer to obtain an emulsified dispersion. Was.

[0098]

Embedded image

<Preparation of Coating Solution> SBR latex (manufactured by Sumitomo Nogatack; "SN-307") was added to the capsule solution containing the diazo compound prepared above at 40% by weight based on the solid content of the capsule. The emulsion was mixed at a weight ratio of 3/2 with respect to the capsule liquid containing the diazo compound to obtain a coating liquid for the magenta layer.

(5) Preparation of yellow thermosensitive recording layer liquid <Preparation of capsule liquid containing diazo compound>
Dibutoxy-4-tolylthiobenzenediazonium hexafluorophosphate (diazo compound: 420 nm
3.0 parts were dissolved in 20 parts of ethyl acetate, and alkylnaphthalene 2 was added as a high boiling point solvent.
0 parts were added and mixed by heating. Xylylene diisocyanate / capsule wall solution was added to the obtained solution.
15 parts of a 1/3 adduct of trimethylolpropane was added and mixed uniformly to obtain a diazo compound solution. A solution of the obtained diazo compound was added to 6% by weight of phthalated gelatin.
54 parts of aqueous solution and sodium dodecyl sulfonate aqueous solution 2
The mixture was added to the mixed solution, and emulsified and dispersed using a homogenizer. 68 parts of water was added to the obtained emulsified dispersion,
The uniformly mixed solution was heated to 40 ° C. while further stirring, and an encapsulation reaction was performed for 3 hours so that the average particle diameter of the capsules was 1.3 μm, to obtain a capsule solution.

<Preparation of Coupler Emulsion Dispersion> 2-Chloro-5- (3- (2,4-di-tert-pentyl) phenoxypropylamino) acetoacetanilide, 2 parts
1 part of 1,2,3-triphenylguanidine, 0.3 part of tricresyl phosphate and 0.1 part of diethyl maleate
Parts in 10 parts of ethyl acetate, 6% by weight of gelatin
The mixture was poured into an aqueous solution obtained by mixing 20 parts of an aqueous solution and 2 parts of a 2% by weight aqueous solution of sodium dodecylsulfonate, and emulsified for 10 minutes using a homogenizer to obtain an emulsified dispersion.

<Preparation of Coating Liquid> The coupler emulsified dispersion prepared above was mixed with the capsule liquid containing the diazo compound at a weight ratio of 3/2 to obtain a coating liquid for a yellow layer.

(6) Preparation of Intermediate Layer Solution Gelatin (manufactured by Nitta Gelatin Co., Ltd .; trade name “# 75”)
0 ") Polyacrylic acid (manufactured by Nippon Pure Chemical Co., Ltd .; trade name" Julima AC-10L ") in 10 parts of a 15% by weight aqueous solution
3 parts by weight of a 15% by weight aqueous solution was added and mixed uniformly to obtain an intermediate layer liquid.

(7) Preparation of Coating Solution for Light Transmittance Adjusting Layer 1.5 parts of the compound shown below, R-6 was added as a reducing agent in 0.1 part.
5 parts, ethyl acetate 6.0 parts and tricresyl phosphate 0.8
And thoroughly dissolved. Xylylene diisocyanate / trimethylolpropane (7
5% ethyl acetate solution: Takeda Pharmaceutical Co .;
10N ") was added to this solution and stirred until uniform. 29.7 parts of an aqueous 8% by weight carboxy-modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd .; "KL-318") was prepared, added to the above solution, and emulsified and dispersed by a homogenizer. The obtained emulsion was added to 40 parts of ion-exchanged water and stirred at 40 ° C. for 3 hours to perform an encapsulation reaction. Thereafter, 7.0 parts of an ion exchange resin "Amberlite MB-03" (manufactured by Organo Corporation) was added, and the mixture was further stirred for 1 hour. Thus, a target coating solution was prepared. The average particle size of the capsule is 0.35 μm
Met.

[0105]

Embedded image

(8) Preparation of Protective Layer Solution EP130 (7% by weight) 100g Water 50g Varifine BF21 dispersion (20% by weight) 10g Surfactant-1 (2% by weight) 5ml Surfactant-2 (5 5% by weight) "EP130" Dodecyl-modified polyvinyl alcohol manufactured by Denki Kagaku Kogyo Co., Ltd. "Varifine BF21 dispersion" is barium sulfate ultrafine particles manufactured by Sakai Chemical Co., Ltd. The above-mentioned surfactant-2 is represented by the following structural formula.

[0107]

Embedded image

(9) Production of Thermal Recording Material 100 (Comparative Example)
On the front side of a paper support laminated with polyethylene,
In order from the support, an undercoat layer solution, a cyan thermosensitive recording layer solution,
Interlayer liquid, magenta thermosensitive recording layer liquid, intermediate layer liquid, yellow feeling
Becomes a thermal recording layer liquid, light transmittance adjusting layer liquid, and protective layer liquid
Multi-layer heat-sensitive recording material 100
I got The amount of coating is equivalent to the solid content after drying.
1.0 g / m ^TwoThe cyan thermosensitive recording layer
6.1 g / m^Two, The intermediate layer is 1.0 g / m^Two, Magenta feeling
Thermal recording layer is 7.8 g / m^Two, The intermediate layer is 1.0 g / m^Two,
7.2 g / m of yellow heat-sensitive recording layer^Two, Light transmittance adjustment layer
Is 1.5 g / m^Two, And the protective layer is 1.2 g / m ^Twoage
Was.

(10) Preparation of heat-sensitive recording material 101 In the same manner as in the preparation of the coating solution for the heat-sensitive recording material 100, except that 5 g of Unitox D-100 (25% by weight) was additionally added to the protective layer, the heat-sensitive recording material 101 was prepared in the same manner. Was prepared.
Here, Unitox D-100 is a dispersion (manufactured by Toyo Petrolite Co., Ltd.) of a compound having a molecular weight of 920 with x / y = 13 / 10.5 in the general formula (1). (11) Preparation of Thermosensitive Recording Material 102 In the thermosensitive recording material 101, the dispersion of Varifine BF21 was added to the light transmittance adjusting layer at 50% by weight (solid content to solid content) based on carboxy-modified polyvinyl alcohol (KL-318). A heat-sensitive recording material 102 was prepared in the same manner except that it was added as needed.

(12) Preparation of Thermosensitive Recording Material 103 In the thermosensitive recording material 102, Unitox D-100 was added to the light transmittance adjusting layer for 25% of Varifine BF21F.
Thermal recording material 10
3 was produced.

(13) Preparation of Thermosensitive Recording Material 104 In the preparation of the coating solution for the magenta thermosensitive recording layer of the thermosensitive recording material 100, Unitox D-100 was coated at a solid content of 0.1%.
A heat-sensitive recording material 104 was produced in the same manner except that the addition was performed so as to be 1 g / m ² .

(14) Preparation of Thermosensitive Recording Material 105 In the thermosensitive recording material 103, zirconia ultrafine particles NZS were used instead of the Varifine BF-21 used for the protective layer.
A thermosensitive recording material 105 was produced in the same manner except that -30B (manufactured by Nissan Chemical Industries, Ltd.) and Unitox D-150 were used instead of Unitox D-100 used for the light transmittance adjusting layer. Here, Unitox D-150
Is a dispersion (manufactured by Toyo Petrolite Co., Ltd.) of a compound having a molecular weight of 1100 with x / y = 18 / 12.5 in the general formula (1).

The heat-sensitive recording materials 100 to 100 obtained in Example 1
105 was evaluated as follows. [Sensitivity] TA printer (printer for full-color thermal recording material) NC300D (manufactured by Fuji Photo Film Co., Ltd.)
The above thermosensitive recording material was used to print 12 steps of stepwise printing from the minimum color density (Dmin) to the maximum color density (Dmax) of the magenta color layer. The magnitude of the color sensitivity was compared based on the density value of the printing energy portion (step) where the printing density D ^magenta ≒ 1.0 of the thermosensitive recording material 100 (Comparative Example). [Glossiness] Gray density DＤ1.0 using NC300D
, And specular reflection at 20 ° incidence was measured with a gloss meter. [Bubble turbidity] Using NC300D, 12 steps of solid printing of cyan were performed, and the degree of bubble turbidity was indicated by the number of steps. The number of steps is counted from the low density side (the larger the number of steps, the better.) [Scratch resistance and head contamination] After performing head cleaning of NC300D, 50 sheets of a pattern in which the print density is changed in a stripe shape in the scanning direction are continuously printed. After printing, the thermal head was observed with an optical microscope to observe the degree of contamination. The number of scratches on the 50 printed prints was counted, and the scratch resistance was determined based on the total number of scratches. Table 2 shows the above results.

[0114]

[Table 2]

[0115]

According to the present invention, a heat-sensitive recording material having high gloss, excellent scratch resistance and excellent recording sensitivity and hardly causing head dirt or cloudiness can be obtained by including the compound in the heat-sensitive recording material. That is, when the compound is added to the protective layer, the dynamic friction with the head is reduced, and the head is hardly stained. Also, by adding inorganic ultra-fine particles to the protective layer or the light transmittance adjusting layer, scratch resistance and stain resistance can be improved, while adding inorganic ultra-fine particles to the light transmittance adjusting layer, the diazo coloring layer The white turbidity caused by the nitrogen gas generated at the time of fixing deteriorates. However, such a disadvantage can be avoided by adding the compound to the light transmittance adjusting layer. Further, when the compound is added to the heat-sensitive recording layer, the sensitivity at the time of image recording is improved. Further, even when added to the heat-sensitive recording layer, the white turbidity can be prevented.

Claims (12)

[Claims] 1. A heat-sensitive recording material comprising at least a heat-sensitive recording layer provided on a support, comprising a compound represented by the following general formula (1). Formula _{(1) CH 3 CH 2 (} CH 2 CH 2) xCH 2 CH 2 (OCH 2 C
H ₂ ) yOH In the above formula, x represents an integer of 7 to 30, and y represents 3 to 100.
Represents an integer. 2. The thermosensitive recording layer according to claim 1, wherein the thermosensitive recording layer has at least one thermosensitive coloring layer mainly composed of a diazonium salt compound, a coupler that reacts with the diazonium salt compound and a binder. The heat-sensitive recording material as described. 3. The heat-sensitive recording layer comprises a heat-sensitive recording layer containing an electron-donating dye and an electron-accepting compound, a diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm, and a color reaction with the diazonium salt compound. Fixing type heat-sensitive recording layer containing a coupler having a maximum absorption wavelength of 400 ± 20.
2. The heat-sensitive recording material according to claim 1, further comprising a photo-fixing type heat-sensitive recording layer containing a diazonium salt compound having a diameter of nm and a coupler which reacts with the diazonium salt compound to form a color. 4. The thermosensitive recording layer has a maximum absorption wavelength of 340.
A photo-fixing type thermosensitive recording layer containing a diazonium salt compound of ± 20 nm or less and a coupler that makes a color reaction with the diazonium salt compound, and a reaction between the diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm and the diazonium salt compound Photo-fixing type thermosensitive recording layer containing a color-forming coupler, and photo-fixing type thermo-sensitive recording containing a diazonium salt compound having a maximum absorption wavelength of 400 ± 20 nm and a coupler which reacts with the diazonium salt compound to form a color. The heat-sensitive recording material according to claim 1, comprising a layer. 5. The heat-sensitive recording material according to claim 1, wherein a protective layer is provided on the heat-sensitive recording layer. 6. The heat-sensitive recording material according to claim 5, wherein a light transmittance adjusting layer is further provided on the heat-sensitive recording layer. 7. The heat-sensitive recording material according to claim 5, wherein the protective layer contains inorganic ultrafine particles. 8. The heat-sensitive recording material according to claim 6, wherein the light transmittance adjusting layer contains inorganic ultrafine particles. 9. The heat-sensitive recording material according to claim 5, wherein the protective layer contains a compound represented by the general formula. 10. The light transmittance adjusting layer contains a compound represented by the general formula.
10. A heat-sensitive recording material according to claim 9. 11. The heat-sensitive recording material according to claim 5, wherein the protective layer contains a long-chain alkyl ether-modified polyvinyl alcohol as a binder. 12. The heat-sensitive recording material according to claim 1, wherein the heat-sensitive recording layer contains a compound represented by the general formula.