JP2001089439A - Diazonium salt and photosensitive and thermal recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a diazonium salt having little fear of explosion and rapid optical decomposition speed and provide a photosensitive and thermal recording material capable of imparting high coloring concentrations, while being optically fixed in high speed and forming durable and high contrast images with little variation in concentrations. SOLUTION: This diazonium salt is expressed by general formula (I) (R1 and R2 are each H, an alkyl or an aryl; R3 and R4 are each H, an alkyl, an aryl or a halogen; R5 to R9 are each H, an alkyl, an aryl, a halogen, an alkoxy, an aryloxy, an alkoxycarbonyl; an acyloxy, carbamoyl, an amide, cyano, an alkylthio, an arylthio, an alkylsulfonyl or an arylsulfonyl; X- is an anion. However, at least one of R5 to R9 expresses a halogen) and this photosensitive and thermal recording material contains the diazonium salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel diazonium salt. The present invention also relates to a light- and heat-sensitive recording material having a diazonium salt and a coupler as color-forming components, and more particularly, to a light- and heat-sensitive recording material capable of obtaining a high color density and forming a high-contrast and robust image.

[0002]

2. Description of the Related Art Various methods for synthesizing azo dye compounds have been known for a long time.
(Maruzen Co., Ltd., Vol. 14-III, pp. 1516-153
As described in 4), there are synthesis by oxidation reaction, synthesis by reduction reaction, synthesis by substitution reaction, synthesis by addition reaction, synthesis by condensation reaction, and other synthesis methods. However, widely used as an industrial production method of azo dye compounds, in view of availability of raw materials, cost, yield, etc., an azo coupling reaction between a diazonium salt and a coupler such as aniline or a phenol is performed. In most cases, there is a risk that the explosion of the diazonium salt may occur. Therefore, the development of a stable diazonium salt having a low risk of explosion has been conventionally demanded.

On the other hand, some skeletons have been proposed as diazonium salt compounds which can be photodecomposed with a light source having a wavelength longer than 400 nm. For example, "Photosen
situ Diazo Compounds an
d their uses ”(1964 the Fo
cal Press London and New
York, p. 57-86), "J. Inf. Rec.
Mater "(1990, 5, p. 383-395). However, these compounds have problems such as a low photodecomposition rate or low stability, and are further applied to a light fixing type thermosensitive recording material (photosensitive thermosensitive recording material) as described later. Improvement was desired.

A diazonium salt is generally a compound having a very high chemical activity, and easily reacts with a compound having a phenol derivative or an active methylene group, so-called a coupler, to form an azo dye and has photosensitivity. Decomposes by light irradiation and loses its activity. Therefore, diazonium salts have been used for a long time as optical recording materials represented by diazo copy ("Photographic Engineering Fundamentals-Non-Silver Salt Photography-" edited by The Photographic Society of Japan, Corona Co. (1982).
p. 89-117, p. 182-201). Furthermore, utilizing the property of decomposing by light and losing activity, it has recently been applied to recording materials that require fixing of images, and a typical example is recording with a recording layer containing a diazonium salt and a coupler. Heat the material according to the image signal
A photo-fixing type heat-sensitive recording material has been proposed in which a reaction is performed, an image is formed, and an image is fixed by irradiation with light (Koji Sato et al., Journal of the Institute of Image Electronics Engineers of Japan, Vol. 11, No. 4 (1982)).
p. 290-296).

However, in these recording materials using a diazonium salt as a color-forming component, the chemical activity of the diazonium salt is extremely high, and even in a dark place, the diazonium salt gradually decomposes and loses its reactivity. Therefore, there was a disadvantage that the shelf life as a recording material was short. In addition, there is a disadvantage that the residual diazonium salt compound is decomposed at the background portion, which is a non-image portion, at the time of light fixing, and the non-image portion is colored due to generation of a colored decomposition product (stain). Furthermore, even in the completed image after fixing, the non-image portion has a weak light resistance, and there is a drawback that coloring is increased when the image is left for a long time under sunlight or a fluorescent lamp.

Various methods have been proposed as means for improving the instability of such diazonium salts. One of the most effective means is to encapsulate a diazonium salt in microcapsules. Microencapsulation of the diazonium salt isolates the diazonium salt from substances that promote decomposition, such as water and bases, so that its decomposition is significantly suppressed and the shelf life of the recording material using it is dramatically improved. (Masamasa Usami et al., "Journal of the Electrographic Society of Japan," Vol. 26, No. 2, (1987) pp. 115-125).

As a general method for encapsulating a diazonium salt in microcapsules, a diazonium salt is dissolved in a hydrophobic solvent (oil phase), and this is added to an aqueous solution (water phase) in which a water-soluble polymer is dissolved. While emulsifying and dispersing with a homogenizer or the like, the monomer or prepolymer serving as the wall material of the microcapsules is added to either the oil phase side or the aqueous phase side, or both, so that the oil phase and the aqueous phase Is a method in which a polymerization reaction is caused at the interface of the polymer or a polymer is precipitated to form a wall made of a polymer compound to form microcapsules. Such a method
For example, it is described in detail in "Microcapsule" (Asashi Kondo, published by Nikkan Kogyo Shimbunsha, 1970), "Microcapsule" (Tamotsu Kondo et al., Published by Sankyo Publishing, 1977) and the like.

[0008] As the capsule wall of the microcapsule to be formed, various materials such as cross-linked gelatin, alginate, celluloses, urea resin, urethane resin, melamine resin and nylon resin can be used. In particular, in the case of a microcapsule having a glass transition temperature such as a urea resin or urethane resin and having a wall whose glass transition temperature is slightly higher than room temperature, at room temperature the capsule wall shows a material non-permeability, Since it shows a substance permeability above the glass transition temperature, it is called a thermoresponsive microcapsule, and it can be said that it is very useful for a thermosensitive recording material.

That is, a heat-sensitive recording material or a heat-sensitive heat-sensitive material in which a thermoresponsive microcapsule containing a diazonium salt on a support and a (photosensitive) heat-sensitive recording layer containing a coupler as a main color-forming component outside the capsule are provided. In the recording material, the diazonium salt can be stably retained for a long period of time, and at the same time, a colored image can be easily formed by heating, and the formed image can be fixed by further irradiating light. The microencapsulation of the diazonium salt makes it possible to dramatically improve the stability as a recording material.

As described above, although the stability as a heat-sensitive recording material (light-sensitive heat-sensitive recording material) is remarkably improved, the instability caused by the diazonium salt itself is not completely suppressed. It has not yet been possible to obtain sufficient long-term storage properties of heat-sensitive recording materials and the like. In addition, even after printing and fixing, if exposed to a light source for a long period of time, the photodegradation product of the diazonium salt causes a photodecomposition reaction, and the coloring stain increases with the reaction, resulting in a non-image after photofixation. There is also a problem that the whiteness of the portion (background portion) is reduced and the contrast with the colored portion is also reduced.

Further, it is known that the photodecomposition reaction as described above cannot occur uniformly and various decomposition products are produced depending on the surrounding environment and the like. This results in a product called photolytic stain, which has absorption in the visible region in particular. Here, if the occurrence of this stain is remarkable, the whiteness of the non-image portion (background portion) after light fixing is reduced, and the contrast with the color-developed portion is also reduced. As a result, the commercial value of the recording material itself is significantly impaired. Become. However, since the photodecomposition reaction of the diazonium salt is complicated and its product is difficult to identify, it is considered difficult to suppress the photodegradation stain.

[0012] Accordingly, in recent years, researches on the improvement of long-term stabilization caused by photodegradation stain have been actively conducted. For example, Japanese Patent Application Laid-Open No. 8-324129 discloses a microcapsule containing a light-fixing type diazonium salt. By using a specific hydrophobic oil together, a light-fixing type heat-sensitive recording material that has excellent raw storability and also has excellent image storability that does not impair whiteness even if exposed to light for a long time after image formation is obtained. Proposed. Further, Japanese Patent Application No. 9-237233 proposes a non-fixing type heat-sensitive recording material using a novel diazonium salt for the purpose of improving the stability of the diazonium salt itself. That is, a diazonium salt having a maximum light absorption wavelength in a shorter wavelength range than near 350 nm is encapsulated in a microcapsule, and a non-fixing type thermosensitive recording material using the microcapsule generally has a wavelength of 350 nm represented by a fluorescent lamp or the like. Improvements regarding whiteness and image storability of a background portion after image formation under a light source having a wavelength longer than the vicinity have been proposed.

However, depending on the preservation environment, raw preservability,
At present, image storability in a color-developed portion and a background portion (non-image portion) after image recording is not yet sufficient, and further improvement in stability is required at present. In recent years, there has been a strong demand for a reduction in recording time required for image recording, that is, a high speed of image formation including printing and fixing. In particular, a light fixing type heat-sensitive recording material using a diazonium salt (photosensitive heat-sensitive recording material). In the above, there is a high demand for a technology capable of achieving high speed while improving the stability as described above, and in order to meet the demand, an improvement in the photolysis rate of the diazonium salt itself is an essential condition. I have.

[0014]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, the present invention has a low explosive
Excellent photodegradability for light in the wavelength region of 50 nm or more,
Another object of the present invention is to provide a diazonium salt having a high decomposition rate. Further, an object of the present invention is to achieve high color density and obtain high-speed light fixing,
An object of the present invention is to provide a light- and heat-sensitive recording material capable of suppressing a decrease in whiteness due to coloring of a non-image portion (background portion) and capable of forming a robust and high-contrast image with little density fluctuation.

[0015]

Means for solving the above problems are as follows. That is, <1> a diazonium salt represented by the following general formula (I).

[0016]

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[Wherein, R ¹ and R ² each independently represent a hydrogen atom, an alkyl group or an aryl group, and R ³ and R ⁴ represent
Each independently represents a hydrogen atom, an alkyl group, an aryl group or a halogen atom. R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represent a hydrogen atom, an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an acyloxy group, a carbamoyl group, an amide group , Cyano group, alkylthio group, arylthio group,
Represents an alkylsulfonyl group or an arylsulfonyl group.
X ^- represents an anion. However, R ⁵ , R ⁶ , R ⁷ , R ⁸ ,
At least one of R ⁹ represents a halogen atom. ]

<2> A diazonium salt represented by the following general formula (II):

[0019]

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[In the formula, R ¹¹ and R ¹² each independently represent an alkyl group, and R ¹³ and R ¹⁴ each independently represent a hydrogen atom, an alkyl group or a halogen atom. Ar represents the following general formula (III), (IV) or (V). X ^- represents an anion. ]

[0021]

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[Wherein, R¹⁶, R¹⁷, R¹⁸Is German
Hydrogen atom, alkyl group, aryl group, halogen atom
, An alkoxy group and an aryloxy group. R^{twenty five}, R
²⁷, R ²⁸, R²⁹Is independently a hydrogen atom, an alkyl
Group, aryl group, halogen atom, alkoxy group, aryl
Roxy represents a group represented by R^{twenty five}And R²⁹At least one is water
Represents an elementary atom. R³⁵, R³⁶, R³⁸Are each independently water
Element atom, alkyl group, aryl group, alkoxy group, ant
Represents a hydroxy group. ]

<3> A diazonium salt represented by the following general formula (VI):

[0024]

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[Wherein, R ²¹ and R ²² each independently represent an alkyl group, and X ⁻ represents an anion. ]

<4> In a light and heat sensitive recording material having a light and heat sensitive recording layer containing a diazonium salt and a coupler on a support, the diazonium salt may be any of the above <1> to <3.
<3> A light- and heat-sensitive recording material, which is the diazonium salt according to any one of <1> to <3>. <5> The light and heat sensitive recording material according to <4>, wherein the diazonium salt is encapsulated in microcapsules. <6> The light- and heat-sensitive recording material according to <5>, wherein the capsule wall of the microcapsule contains polyurethane and / or polyurea as a component.

<7> The coupler has the following general formula (VII)
<4> is a compound represented by the formula: or a tautomer thereof
<6> The light- and heat-sensitive recording material according to any one of <1> to <6>.

[0028]

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[In the formula, E ¹ and E ² each independently represent an electron-withdrawing group, and E ¹ and E ² may combine to form a ring. ]

<8> The light and heat sensitive recording material according to any one of the items <4> to <7>, wherein the light and heat sensitive recording layer contains an organic base.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the diazonium salt and the light and heat sensitive recording material of the present invention will be described in detail. <Diazonium salt> The diazonium salt of the present invention is represented by the following general formula (I).

[0032]

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In the general formula (I), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group or an aryl group. The alkyl group is preferably an alkyl group having 1 to 20 carbon atoms, and may be unsubstituted or may have a substituent, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl Group, t-butyl group, n-hexyl group, n-octyl group, 2-ethylhexyl group, 3,5,
5-trimethylhexyl group, n-decyl group, n-dodecyl group, 2-chloroethyl group, 2-methanesulfonylethyl group, 2-methoxyethyl group, N, N-dibutylcarbamoylmethyl group, 2-ethoxycarbonylethyl group, Butoxycarbonylmethyl group, 2-isopropyloxyethyl group, 2- (2,5-di-t-amylphenoxy) ethyl group, 2-phenoxyethyl group, 1- (4-methoxyphenoxy) -2-propyl group, 1 -(2,5-di-t
-Amylphenoxy) -2-propyl group, allyl group, benzyl group, α-methylbenzyl group, 4-chlorobenzyl group, 2-chlorobenzyl group, 3,4-dichlorobenzyl group, 4-fluorobenzyl group, trichloromethyl Group, trifluoromethyl group, 2,2,2-trifluoromethyl group and the like.

The aryl group has 6 to 30 carbon atoms.
The aryl group is preferably unsubstituted or may have a substituent, and examples thereof include a phenyl group, a 4-methylphenyl group, and a 2-chlorophenyl group. Among them, an aryl group having 6 to 10 carbon atoms is more preferable, and a phenyl group and a 4-methylphenyl group are particularly preferable.

When R ¹ and R ² are alkyl groups, R ¹
And R ² may combine with each other to form a ring structure and form a cyclic group containing a nitrogen atom. As the cyclic group,
For example, a pyrrolidino group, a piperidino group, a morpholino group,
4-octanoylpiperazino group, 4- (2- (2,4-
Di-t-amylphenoxy)) butanoylpiperazino group, 4- (2- (n-octyloxy) -5-t-octylphenyl) sulfonylpiperazino group, hexamethyleneimino group, indolino group and the like. Of these, a pyrrolidino group and a hexamethyleneimino group are preferred.

It is more preferable that at least one of R ¹ and R ² in the general formula (I) is a methyl group.

R ³ and R ^{4 in} formula (I) each independently represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom. The alkyl group and the aryl group are the same as those of the R
Above it is the same as those in the ¹ and R ^2. Further, it is more preferable that at least one of R ³ and R ⁴ in the general formula (I) is a methyl group. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom,
An iodine atom is mentioned, and among them, a fluorine atom and a chlorine atom are preferable.

R ⁵ , R ⁶ , R ⁷ , R ⁸ , R in the general formula (I)
⁹ is each independently a hydrogen atom, an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group,
Represents an alkoxycarbonyl group, an acyloxy group, a carbamoyl group, an amide group, a cyano group, an alkylthio group, an arylthio group, an alkylsulfonyl group, or an arylsulfonyl group. Here, at least one of R ^{5 to} R ⁹ represents a halogen atom. The alkyl group and the aryl group have the same meaning as in R ¹ and R ² , and the halogen atom has the same meaning as in R ³ and R ⁴ .

The alkoxy group has 1 to 2 carbon atoms.
An alkoxy group of 0 is preferable, and may be unsubstituted or may have a substituent. For example, a methoxy group, an ethoxy group, an n-
Butoxy, t-butoxy, hexyloxy, octyloxy, 2-ethylhexyloxy, trifluoromethoxy, 2-ethoxyethoxy, 2-chloroethoxy, 2-phenoxyethoxy, benzyloxy, 2 -Chlorobenzyloxy group, 4-chlorobenzyloxy group, 3,4-dichlorobenzyloxy group, allyloxy-2,4-di-t-amylphenoxyethoxy group, 2,4-di-t-amylphenoxybutoxy group, etc. Is mentioned. Among them, an alkoxy group having 1 to 10 carbon atoms is more preferable, and a methoxy group, an ethoxy group, an n-butoxy group, and a benzyloxy group are particularly preferable.

The aryloxy group has 6 carbon atoms.
To 20 aryloxy groups are preferred, and may be unsubstituted or substituted. For example, a phenoxy group, a 4-methylphenoxy group, a 4-methoxyphenoxy group, a 4-chlorophenoxy group, a 2-chlorophenoxy group , 2,4-
And a di-t-amylphenoxy group. Among them,
An aryloxy group having 6 to 10 carbon atoms is more preferable, and a phenoxy group, a 4-methylphenoxy group, and a 4-methoxyphenoxy group are particularly preferable.

The alkoxycarbonyl group is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, and may be unsubstituted or substituted. For example, a methoxycarbonyl group, an ethoxycarbonyl group, an n-butoxycarbonyl group , 2-ethoxyethoxycarbonyl group and the like. Among them, an alkoxycarbonyl group having 2 to 10 carbon atoms is more preferable, and a methoxycarbonyl group, an ethoxycarbonyl group, and an n-butoxycarbonyl group are particularly preferable.

The acyloxy group has 2 to 2 carbon atoms.
20 acyloxy groups are preferred, and may be unsubstituted or have a substituent. Examples thereof include an acetyloxy group, a butanoyloxy group, a chloroacetyloxy group, a phenoxyacetyloxy group, and a benzoyloxy group.
Among them, an acyloxy group having 3 to 10 carbon atoms is more preferable, and an acetyloxy group, a phenoxyacetyloxy group,
Benzoyloxy groups are particularly preferred.

The carbamoyl group has 1 to 1 carbon atoms.
20 carbamoyl groups are preferred, and may be unsubstituted or substituted. For example, an unsubstituted carbamoyl group,
N, N-dimethylcarbamoyl group, piperidinocarbonyl group, N, N-di (2-ethylhexyl) carbamoyl group, and the like. Among them, a carbamoyl group having 1 to 10 carbon atoms is more preferable, and an unsubstituted carbamoyl group and a piperidinocarbonyl group are particularly preferable.

The amide group is preferably an amide group having 2 to 20 carbon atoms, and may be unsubstituted or substituted. Examples thereof include an acetylamino group, a butanoylamino group, a pivaloylamino group and an octanoylamino group. Group, benzoylamino group and the like. Among them, carbon number 2-1
An amide group of 0 is more preferred, and an acetylamino group and a butanoylamino group are particularly preferred.

The alkylthio group has 1 to 1 carbon atoms.
Preferred are 20 alkylthio groups, which may be unsubstituted or substituted, such as methylthio, ethylthio, butylthio, octylthio, 2-ethylhexylthio, dodecylthio, benzylthio, and the like. Among them, an alkylthio group having 1 to 10 carbon atoms is more preferable, and a methylthio group, an ethylthio group, a butylthio group, and a benzylthio group are particularly preferable.

The arylthio group has 6 to 6 carbon atoms.
Preferred are 20 arylthio groups, which may be unsubstituted or substituted, and include, for example, a phenylthio group, a 4-chlorophenylthio group, a 2-chlorophenylthio group, and a 4-methylthio group. Among them, an arylthio group having 6 to 10 carbon atoms is more preferable, and a phenylthio group, 2-
A chlorophenylthio group is particularly preferred.

The alkylsulfonyl group is preferably an alkylsulfonyl group having 1 to 20 carbon atoms, and may be unsubstituted or have a substituent. For example, a methylsulfonyl group, an ethylsulfonyl group, a butylsulfonyl group, an octyl group Examples include a sulfonyl group, a dodecylsulfonyl group, a benzylsulfonyl group and the like. Among them, carbon number 1-10
Is more preferable, and a methylsulfonyl group, an ethylsulfonyl group, a butylsulfonyl group, and a benzylsulfonyl group are particularly preferable.

The arylsulfonyl group is preferably an arylsulfonyl group having 1 to 20 carbon atoms, and may be unsubstituted or have a substituent. For example, a phenylsulfonyl group, 4-chlorophenylsulfonyl group, 2-chlorophenyl Examples include a sulfonyl group and a 4-methylsulfonyl group. Among them, an arylsulfonyl group having 6 to 10 carbon atoms is more preferable, and a phenylsulfonyl group and a 2-chlorophenylsulfonyl group are particularly preferable.

When each of the groups represented by R ^{1 to} R ⁹ has a substituent, examples of the substituent include those represented by general formula (I), general formula (II) and general formula (VI) described below. Or a dimer of the diazonium salt or a multimer of the diazonium salt may be formed.

[0050] X in the general Formulas (I) ^- represents an anion. The anion may be either an inorganic anion or an organic anion. Preferable examples of the inorganic anion include hexafluorophosphate ion, borofluoride ion, chloride ion, sulfate ion, and hydrogensulfate ion. Is preferred. As the organic anion, for example, a polyfluoroalkyl sulfonate ion, a polyfluoroalkyl carboxylate ion, a tetraphenyl borate ion, an aromatic carboxylate ion, an aromatic sulfonate ion and the like are preferably mentioned. Fluoroalkyl sulfonate ions are more preferred.

Among the diazonium salts represented by the general formula (I), a diazonium salt represented by the following general formula (II) is preferable.

[0052]

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In the general formula (II), R ¹¹ and R ¹² each independently represent an alkyl group, and the alkyl group has the same meaning as R ¹ and R ² in the general formula (I).
R ¹³ and R ¹⁴ each independently represent a hydrogen atom, an alkyl group, or a halogen atom;
It has the same meaning as ¹ and R ² , and the halogen atom has the same meaning as R ³ and R ⁴ in the general formula (I). X ^-
Represents an anion and has the same meaning as that in the general formula (I). At least one of R ¹¹ and R ¹² ;
Preferably, at least one of R ¹³ and R ¹⁴ is each a methyl group.

Ar in the general formula (II) represents the following general formula (III), (IV) or (V).

[0055]

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R ¹⁶ , R ¹⁷ and R in the general formula (III)
¹⁸ independently represents a hydrogen atom, an alkyl group, an aryl group, a halogen atom, an alkoxy group, or an aryloxy group. R ²⁵ , R ²⁷ , R ²⁸ and R ^{29 in the} general formula (IV)
Represents a hydrogen atom, an alkyl group, an aryl group, a halogen atom, an alkoxy group, or an aryloxy group, and at least one of R ²⁵ and R ²⁹ represents a hydrogen atom. R ³⁵ , R ³⁶ and R ³⁸ in the general formula (V) each independently represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, or an aryloxy group. Each alkyl group and aryl group in the general formulas (III) to (V) has the same meaning as in the case of R ¹ and R ² in the general formula (I), and the halogen atom is a group represented by R ³ and R ⁴ . And the alkoxy group and the aryloxy group are each represented by R ⁵ to R ⁵ in the general formula (I).
It is the same as R ⁹ .

Further, among the diazonium salts represented by the general formula (II), a diazonium salt represented by the following general formula (VI) is more preferable.

[0058]

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In the general formula (VI), R^{twenty one}And R^{twenty two}Is
Each independently represents an alkyl group; ^-Represents an anion
The alkyl group and the anion are represented by the general formula (I)
R in¹, R^TwoAnd X^-Is synonymous with The R^{twenty one}
And R^{twenty two}As at least one of them is methyl
It is preferably a benzyl group.

The following formulas (I), (II) and (V
Specific examples of the diazonium salt represented by I) are shown below, but the present invention is not limited thereto.

[0061]

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[0062]

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[0063]

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[0064]

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[0065]

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The diazonium salt represented by any of formulas (I), (II) and (VI) can be produced by a known method. That is, it can be synthesized by diazotizing the corresponding aniline using sodium nitrite, nitrosylsulfuric acid, isoamyl nitrite or the like in an acidic solvent.

The diazonium salts represented by the general formulas (I), (II) and (VI) may be oily or crystalline, but they are crystalline at room temperature in terms of handleability. Is preferred. These diazonium salts may be used alone or in combination of two or more, or may be used in combination with existing diazonium salts.

When the diazonium salt is used in a light and heat sensitive recording layer of a light and heat sensitive recording material, the content thereof is preferably 0.02 to 5 g / m ² , and 0.1 to 4 g in terms of color density. / M ² is more preferred.

For stabilization of the diazonium salt of the present invention, a complex compound can be formed by using zinc chloride, cadmium chloride, tin chloride or the like to stabilize the diazonium salt.

The diazonium salts represented by the above general formulas (I), (II) and (VI) form a color by a reaction with a coupler described later to obtain a high color-forming density, while obtaining a high color density.
It has excellent photodecomposability in the wavelength range of 80 to 460 nm and has a high-speed decomposability that can sufficiently complete fixing even with short-time light irradiation. Useful.

<Coupler> Next, a coupler (coupling component) usable in the light and heat sensitive recording material of the present invention.
Will be described. As the coupler, any compound can be used as long as it can form a dye by coupling with a diazonium salt in a basic atmosphere and / or a neutral atmosphere. 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, a so-called active methylene compound having a methylene group next to a carbonyl group, a phenol derivative,
There are naphthol derivatives and the like, and specific examples include the following, which are used within a range that meets the purpose of the present invention.

Specific examples of the coupler include, for example,
Resorcin, phloroglucin, 2,3-dihydroxynaphthalene, sodium 2,3-dihydroxynaphthalene-6-sulfonate, morpholinopropylamide 1-hydroxy-2-naphthoate, 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-3,6-disulfonate sodium, 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'-dicyclohexyl barbituric acid, N, N'-di-n-dodecyl barbituric acid, N-
n-octyl-N'-n-otatadecyl barbituric acid, N-phenyl-N '-(2,5-di-n-octyl oxdiphenyl) barbituric acid, N, N'-bis (octadecyloxycarbonyl) Methyl) 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- (pivaloylacetamidomethyl) benzene, benzoylacetonitrile, thenoylacetonitrile, acetoacetanilide,
Benzoylacetanilide, pivaloylacetanilide, 2-chloro-5- (Nn-butylsulfamoyl) -1-bivaloylacetamidobenzene, 1- (2
-Ethylhexyloxypropyl) -3-cyano-4-
Methyl-6-hydroxy-1,2-dihydropyridine-
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.

The details of the coupler are described in JP-A-4-4-2.
01483, JP-A-7-223267, JP-A-7-223
223368, JP-A-7-323660, Japanese Patent Application No. 5
-278608, Japanese Patent Application No. 5-297024, Japanese Patent Application No. 6-18669, Japanese Patent Application No. 6-18670, Japanese Patent Application No. 7
No. 316280, Japanese Patent Application No. 8-027095, Japanese Patent Application No. 8-027096, Japanese Patent Application No. 8-030799, Japanese Patent Application No. 8-12610, Japanese Patent Application No. 8-132394, Japanese Patent Application No. 8-358755. And Japanese Patent Application Nos. 8-358756 and 9-0699990.

Of the above, in the present invention, a compound represented by the following formula (VII) or a tautomer thereof is particularly preferred. Hereinafter, the coupler represented by formula (VII) will be described in detail.

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[Wherein, E ¹ and E ² each independently represent an electron-withdrawing group, and E ¹ and E ² may combine to form a ring. ]

The electron-withdrawing group represented by E ¹ and E ² means a substituent having a positive Hammett σ _p value, which may be the same or different. Acetyl, propionyl, pivaloyl, chloroacetyl, trichloroacetyl, trifluoroacetyl, 1-methylcyclopropylcarbonyl, 1
Acyl groups such as -ethylcyclopropylcarbonyl group, 1-benzylcyclopropylcarbonyl group, benzoyl group, 4-methoxybenzoyl group, and thenoyl group; methoxycarbonyl group, ethoxycarbonyl group, 2-methoxyethoxycarbonyl group, 4-methoxyphenoxy An oxycarbonyl group such as a carbonyl group; a carbamoyl group, N, N-
Dimethylcarbamoyl group, N, N-diethylcarbamoyl group, N-phenylcarbamoyl group, N- [2,4-bis (pentyloxy) phenyl] carbamoyl group, N-
Carbamoyl groups such as [2,4-bis (octyloxy) phenyl] carbamoyl group and morpholinocarbonyl group;
Alkylsulfonyl or arylsulfonyl such as methanesulfonyl, benzenesulfonyl and toluenesulfonyl; phosphono such as diethylphosphono; benzoxazol-2-yl, benzothiazole-2-
Yl group, 3,4-dihydroquinazolin-4-one-2-
Yl group, 3,4-dihydroquinazoline-4-sulfone-
A heterocyclic group such as a 2-yl group; a heterocyclic group; a nitro group; an imino group;

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

Hereinafter, specific examples of the coupler represented by the general formula (VII) are shown, but the present invention is not limited thereto. In addition, the tautomers of the couplers shown below can also be mentioned as preferable ones.

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The tautomers of the above-mentioned couplers are those which exist as isomers of the above-mentioned couplers and which have a relationship in which the structure easily changes between the two. The tautomers are also preferable as the coupler used in the above.

<Microencapsulation> In the light- and heat-sensitive recording material of the present invention, it is preferable that a diazonium salt is encapsulated in microcapsules for the purpose of improving the raw preservability before use. The method for forming the microcapsules can be appropriately selected from known methods. As the polymer substance forming the capsule wall of the microcapsule, it is impermeable at room temperature and needs to have a property of being permeable at the time of heating. Preferred are, for example, polyurethane, polyurea, polyamide, polyester, urea / formaldehyde resin, melamine resin, polystyrene, styrene / methacrylate copolymer, styrene / acrylate copolymer, and a mixture thereof.

As a method for forming microcapsules, specifically, an interfacial polymerization method or an internal polymerization method is suitable. For details of the capsule forming method and specific examples of the reactants, see US Pat. Nos. 3,726,804 and 3,795.
No. 6,669 and the like. For example, when polyurea or polyurethane is used as the capsule wall material, a polyisocyanate and a second substance (for example, polyol or polyamine) which reacts with the polyisocyanate to form a capsule wall are mixed in an aqueous medium or an oil medium to be encapsulated. Then, these are emulsified and dispersed in water and then heated to cause a polymer forming reaction at the oil droplet interface to form a microcapsule wall. Note that polyurea can be produced even when the addition of the second substance is omitted.

In the present invention, the polymer substance forming the capsule wall of the microcapsule preferably contains at least one of polyurethane and polyurea as a component.

Next, a method for producing diazonium salt-containing microcapsules (polyurea / polyurethane wall) will be described. First, a diazonium salt is dissolved or dispersed in a hydrophobic organic solvent serving as a core of a capsule to prepare an oil phase serving as a core of a microcapsule. At this time, a polyvalent isocyanate is further added as a wall material.

In preparing the oil phase, the hydrophobic organic solvent used for forming the core of the microcapsules by dissolving and dispersing the diazonium salt is preferably an organic solvent having a boiling point of 100 to 300 ° C., for example, alkylnaphthalene, Alkyl diphenyl ethane, alkyl diphenyl methane, alkyl biphenyl, alkyl terphenyl, chlorinated paraffin, phosphates, maleates, adipic esters, phthalates, benzoates, carbonates, ethers, Sulfuric esters, sulfonic esters and the like can be mentioned. These are 2
You may mix and use more than one kind.

When the solubility of the diazonium salt to be encapsulated in the above-mentioned organic solvent is poor, a low-boiling solvent having high solubility of the diazonium salt to be used can be used in combination, and as the low-boiling solvent, For example, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, methylene chloride, tetrahydrofuran, acetonitrile, acetone and the like can be mentioned. For this reason, the diazonium salt preferably has an appropriate solubility in a high-boiling hydrophobic organic solvent and a low-boiling solvent, and specifically, has a solubility of 5% or more in the solvent. preferable. The solubility in water is preferably 1% or less.

On the other hand, an aqueous solution in which a water-soluble polymer is dissolved is used for the aqueous phase to be used. After the oil phase is charged into the aqueous phase, emulsification and dispersion are performed by means of a homogenizer or the like. And acts as a dispersion medium for stabilizing the emulsified aqueous solution. Here, in order to more uniformly emulsify and disperse and stabilize, a surfactant may be added to at least one of the oil phase and the aqueous phase. As the surfactant, a known surfactant for emulsification can be used. The addition amount of the surfactant is preferably 0.1 to 5% by weight based on the weight of the oil phase,
0.5 to 2% by weight is more preferred.

The water-soluble polymer used in the aqueous solution of the prepared water-soluble polymer in which the oil phase is dispersed is preferably a water-soluble polymer having a solubility in water of 5% or more at the temperature at which the emulsion is to be emulsified. And modified products thereof, polyacrylamide and its derivatives, ethylene-
Vinyl acetate copolymer, styrene-maleic anhydride copolymer, ethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyvinylpyrrolidone, ethylene-acrylic acid copolymer, vinyl acetate-acrylic acid copolymer Examples include polymers, carboxymethylcellulose, methylcellulose, casein, gelatin, starch derivatives, gum arabic, sodium alginate and the like.

The water-soluble polymer preferably has no or low reactivity with an isocyanate compound.
For example, those having a reactive amino group in the molecular chain, such as gelatin, are preferably modified beforehand to eliminate the reactivity.

As the polyvalent isocyanate compound,
A compound having a trifunctional or higher isocyanate group is preferable, but a bifunctional isocyanate compound may be used.
Specifically, diisocyanates such as xylene diisocyanate and its hydrogenated product, hexamethylene diisocyanate, tolylene diisocyanate and its hydrogenated product, and isophorone diisocyanate are used as main raw materials, and dimers or trimers of these (buret or isocyanate) are used. Nurate), as well as polyfunctional adducts of polyols such as trimethylolpropane and bifunctional isocyanates such as xylylene diisocyanate, and adducts of polyols such as trimethylolpropane and bifunctional isocyanates such as xylylene diisocyanate And a compound in which a high molecular weight compound such as polyether having active hydrogen such as polyethylene oxide is introduced, and a formalin condensate of benzene isocyanate. JP-A-62-21
Compounds described in JP-A-2190, JP-A-4-26189, JP-A-5-317694, Japanese Patent Application No. 8-268721, and the like are preferred.

The amount of the polyvalent isocyanate used is determined so that the average particle size of the microcapsules is 0.3 to 12 μm and the wall thickness is 0.01 to 0.3 μm. The diameter of the dispersed particles is generally about 0.2 to 10 μm. In the emulsified dispersion obtained by adding an oil phase to an aqueous phase, a polyurea isocyanate polymerization reaction occurs at the interface between the oil phase and the aqueous phase to form a polyurea wall.

If a polyol and / or a polyamine is further added to the hydrophobic solvent in the aqueous phase or the oil phase, it can be used as one of the components of the microcapsule wall by reacting with the polyvalent isocyanate. . In the above reaction, it is preferable to keep the reaction temperature high or to add an appropriate polymerization catalyst from the viewpoint of increasing the reaction rate. Specific examples of these polyols or polyamines include propylene glycol, glycerin, trimethylolpropane,
Triethanolamine, sorbitol, hexamethylenediamine and the like. When a polyol is added, a polyurethane wall is formed. Details of polyvalent isocyanates, polyols, reaction catalysts, and polyamines for forming a part of the wall material are described in detail in Polygraphs (Polyurethane Handbook, edited by Keiji Iwata, Nikkan Kogyo Shimbun (1987)).

The emulsification can be carried out by appropriately selecting from known emulsifying apparatuses such as a homogenizer, a Manton-Gorry, an ultrasonic disperser, a dissolver and a Keddy mill.
After the emulsification, the emulsion is heated to 30 to 70 ° C. in order to promote the capsule wall forming reaction. During the reaction, in order to prevent aggregation of the capsules, it is necessary to lower the probability of collision between the capsules by adding water or to perform sufficient stirring.

During the reaction, a dispersion for preventing aggregation may be added again. Generation of carbon dioxide gas is observed with the progress of the polymerization reaction, and the end thereof can be regarded as an approximate end point of the capsule wall forming reaction. Usually, by reacting for several hours, a desired diazonium salt-encapsulated microcapsule can be obtained.

The coupler used in the present invention can be used as a solid dispersion with a water-soluble polymer, an organic base, other color-forming auxiliaries and the like by a sand mill or the like. After being dissolved in a high-boiling organic solvent that is hardly soluble or insoluble in water, this is dissolved in a surfactant and / or
Alternatively, it is preferably used as an emulsified dispersion obtained by mixing with a polymer aqueous solution (aqueous phase) containing a water-soluble polymer as a protective colloid and emulsifying with a homogenizer or the like. In this case, if necessary, a low boiling point solvent can be used as a dissolution aid. Further, the coupler and the organic base can be separately emulsified and dispersed, or can be mixed and then dissolved in a high boiling point organic solvent to be emulsified and dispersed. The preferred emulsified dispersion particle size is 1 μm or less.

The amount of the coupler to be used is preferably 0.1 to 30 parts by weight based on 1 part by weight of the diazonium salt.

The high boiling organic solvent used in this case is
For example, it can be appropriately selected from high boiling oils described in JP-A-2-141279. Among them, esters are preferable and tricresyl phosphate is particularly preferable from the viewpoint of the emulsion stability of the emulsified dispersion. It is also possible to use the above oils together or with other oils.

In the above organic solvent, further as a dissolution aid,
An auxiliary solvent having a low boiling point can be added, and examples of the auxiliary solvent include, for example, ethyl acetate, isopropyl acetate, butyl acetate, and methylene chloride. Depending on the case, it is also possible to use only low-boiling auxiliary solvents without high-boiling oils.

The water-soluble polymer to be contained as a protective colloid in the aqueous phase includes known anionic polymers,
It can be appropriately selected from nonionic polymers and amphoteric polymers, and among them, for example, polyvinyl alcohol, gelatin, cellulose derivatives and the like are preferable.

As the surfactant to be contained in the aqueous phase, an anionic or nonionic surfactant which does not cause precipitation or aggregation by acting with the above protective colloid is appropriately selected and used. can do. Examples of the surfactant include sodium alkylbenzene sulfonate, sodium alkyl sulfate, dioctyl sodium sulfosuccinate, polyalkylene glycol (for example, polyoxyethylene nonylphenyl ether) and the like.

In the present invention, in a preferred embodiment, an organic base is added as a basic substance for the purpose of promoting the coupling reaction between the diazonium salt and the coupler.
Examples of the organic base include nitrogen-containing compounds such as tertiary amines, piperidines, piperazines, amidines, formamidines, pyridines, guanidines, morpholines, and the like. -46806, JP-A-62-70082, JP-A-57-16
9745, JP-A-60-94381, JP-A-57-123086, JP-A-60-49991
JP-B, JP-B-2-24916, JP-B-2-28
479, JP-A-60-165288, and JP-A-57-185430 can be suitably mentioned. These may be used alone or in combination of two or more.

Of the above, specifically, N, N'-bis (3-phenoxy-2-hydroxypropyl) piperazine, N, N'-bis [3- (p-methylphenoxy)-
2-hydroxypropyl] piperazine, N, N′-bis [3- (p-methoxyphenoxy) -2-hydroxypropyl] piperazine, N, N′-bis (3-phenylthio-2-hydroxypropyl) piperazine, N, N N'-
Bis [3- (β-naphthoxy) -2-hydroxypropyl] piperazine, N-3- (β-naphthoxy) -2-hydroxypropyl-N′-methylpiperazine, 1,4-
Piperazines such as bis {[3- (N-methylpiperazino) -2-hydroxy] propyloxy) benzene;
[3- (β-naphthoxy) -2-hydroxy] propylmorpholine, 1,4-bis (3-morpholino-2-hydroxy-propyloxy) benzene, 1,8-bis (3
Morpholinos such as -morpholino-2-hydroxy-propyloxy) benzene, piperidines such as N- (3-phenoxy-2-hydroxypropyl) piperidine, N-dodecylpiperidine, triphenylguanidine, tricyclohexylguanidine, dicyclohexylphenylguanidine And the like are preferable.

The amount of the organic base to be used is preferably 0.1 to 30 parts by weight based on 1 part by weight of the diazonium salt. If the amount is less than 0.1 part by weight, a sufficient color density may not be obtained. If the amount exceeds 30 parts by weight, decomposition of the diazonium salt may be promoted.

Further, in addition to the above-mentioned organic base, a coloring aid may be added to the photosensitive and heat-sensitive recording layer for the purpose of accelerating the coloring reaction, that is, rapidly and completely thermally printing with low energy. Here, the coloring aid is a substance that increases the coloring density during heating recording or controls the coloring temperature, such as lowering the melting point of a coupler, a basic substance or a diazonium salt, or the softening point of the capsule wall. The condition is such that a diazonium salt, a basic substance, a coupler, and the like are easily reacted by an action capable of lowering the concentration. Examples of the coloring aid include phenol derivatives, naphthol derivatives, alkoxy-substituted benzenes, alkoxy-substituted naphthalenes, aromatic ethers, thioethers, esters, amides, ureides, urethanes, sulfonamide compounds, and hydroxy compounds.

The coloring aid also includes a heat-meltable substance. The heat-meltable substance is a substance that is solid at room temperature and melts by heating and has a melting point of 50 ° C. to 150 ° C., and is a substance that can dissolve a diazonium salt, a coupler, an organic base, or the like. Specific examples include carboxylic amides, N-substituted carboxylic amides, ketone compounds, urea compounds, esters and the like.

In the light and heat sensitive recording material of the present invention, the light and heat fastness of a thermochromic image is improved, or
For the purpose of reducing the yellowing of the unprinted portion (non-image portion) after fixing by light, it is also preferable to use the following known antioxidants and the like. Regarding the antioxidant, for example, European Patent Publication Nos. 223739 and 3094
Nos. 01, 309402 and 31055
No. 1, No. 310552, No. 559416
No. 3,435,443, JP-A-54-48535, JP-A-62-262047, JP-A-63-113536, and JP-A-63-16335.
No. 1, JP-A-2-262654, JP-A-2-262654
No. 71262, JP-A-3-121449, JP-A-5-61166, JP-A-5-119449, U.S. Pat. No. 4,814,262, U.S. Pat. No. 4,980,275, and the like.

It is also effective to use various known additives already used in heat-sensitive or pressure-sensitive recording materials. Examples of the various additives include, for example, JP-A-60-1
Nos. 07384, 60-107383 and 6
Nos. 0-125470, 60-125471, 60-125472 and 60-28748.
No. 5, JP-A-60-287486, JP-A-60-28
Nos. 7487, 60-287488, 61
JP-160287, JP-A-61-185483,
Nos. 61-211079, 62-146678, 62-146680, and 62-1466
No. 79, 62-282885, 63-0
Nos. 51174, 63-89877, 63
JP-A-88380, JP-A-63-088381, JP-A-63-203372, JP-A-63-224989, JP-A-63-251282, and JP-A-63-26759.
No. 4, JP-A-63-182484, and JP-A No. 1-2
JP-A-39282, JP-A-4-291885, JP-A-4-291885
291684, 5-188687, 5
Compounds described in JP-A-188686, JP-A-5-110490, JP-A-5-170361, JP-B-48-043294, JP-A-48-033212 and the like can be mentioned.

Specifically, 6-ethoxy-1-phenyl-2,2,4-trimethyl-1,2-dihydroquinoline, 6-ethoxy-1-octyl-2,2,4-trimethyl-1,2 -Dihydroquinoline, 6-ethoxy-1-
Phenyl-2,2.4-trimethyl-1,2,3,4-
Tetrahydroquinoline, 6-ethoxy-1-octyl-
2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline, nickel cyclohexanoate, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) -2- Ethyl hexane, 2
-Methyl-4-methoxy-diphenylamine, 1-methyl-2-phenylindole and the like.

The amount of the antioxidant or various additives to be added is 0.05 to 1 part by weight of the diazonium salt.
It is preferably from 100 to 100 parts by weight, more preferably from 0.2 to 30 parts by weight.

The antioxidant and various additives may be contained in a microcapsule together with a diazonium salt, or may be contained as a solid dispersion together with a coupler, a basic substance and other color-forming auxiliaries. It may be emulsified and contained together with a suitable emulsifying aid, or may be contained in both forms. Further, the antioxidant or various additives may be used alone or in combination of two or more. Further, it can be contained in a protective layer.

The antioxidants and various additives do not necessarily have to be added to the same layer. The antioxidant and / or
Or, when using a plurality of various additives in combination, aniline, alkoxybenzenes, binder phenols, hindered amines, hydroquinone derivatives, phosphorus compounds, structurally categorized as sulfur compounds, mutually different structures. These may be combined, or a plurality of the same may be combined.

For the purpose of reducing the yellowing of the background after image recording, a free radical generator (a compound that generates free radicals upon irradiation with light) used in a photopolymerizable composition or the like can be added. Examples of the free radical generator include aromatic ketones, quinones, benzoin, benzoin ethers, azo compounds, organic disulfides, acyl oxime esters, and the like. The amount of the free radical generator is 0.01 to 1 part by weight of the diazonium salt.
5 parts by weight are preferred.

Similarly, for the purpose of reducing yellow coloration, a polymerizable compound having an ethylenically unsaturated bond (hereinafter referred to as a compound having an ethylenically unsaturated bond)
It is called "vinyl monomer". ) Can also be used. A vinyl monomer is a compound having at least one ethylenically unsaturated bond (vinyl group, vinylidene group, etc.) in its chemical structure, and has a chemical form of a monomer or prepolymer. Examples of the vinyl monomer include unsaturated carboxylic acids and salts thereof, esters of unsaturated carboxylic acids and aliphatic polyhydric alcohols, and amides of unsaturated carboxylic acids and aliphatic polyamine compounds. The vinyl monomer is used in an amount of 0.2 to 20 parts by weight based on 1 part by weight of the diazonium salt. The free radical generator and the vinyl monomer can be used in a microcapsule together with a diazonium salt.

Further, citric acid, tartaric acid, oxalic acid, boric acid, phosphoric acid, pyrophosphoric acid and the like can be added as an acid stabilizer.

<Photosensitive and Thermosensitive Recording Material> The photosensitive and thermosensitive recording material of the present invention has at least a photosensitive and thermosensitive recording layer on a support, and the photosensitive and thermosensitive recording layer has at least one of the general formulas (I) and (II). And a diazonium salt represented by any of (VI) and a coupler, and if necessary,
It has an organic base and other additives. The diazonium salts represented by formulas (I), (II) and (VI) may be used in combination of two or more. The light- and heat-sensitive recording layer contains a microcapsule containing a diazonium salt represented by any of formulas (I), (II) and (VI), a coupler, and if necessary, an organic base and other additives. A coating solution can be prepared by preparing a coating solution to be contained, applying the coating solution on a support such as paper or a synthetic resin film, and drying. In the present invention, an embodiment in which the light- and heat-sensitive recording layer contains an organic base is preferable.

The coating can be appropriately selected from known coating methods, and includes, for example, bar coating, blade coating, air knife coating, gravure coating, roll coating coating, spray coating, dip coating, curtain coating and the like. Can be The dry coating amount of the light and heat sensitive recording layer after coating and drying is preferably 2.5 to 30 g / m ² .

The constitution of the light and heat sensitive recording layer in the light and heat sensitive recording material of the present invention is not particularly limited. For example, a single layer in which microcapsules, couplers, organic bases and the like are all contained in the same layer is used. Or a multi-layer laminated type included in another layer. Also, on a support, Japanese Patent Application No. 59-17
After the formation of the intermediate layer described in the specification of JP-A-7669, etc., the photosensitive and heat-sensitive recording layer may be applied and formed. further,
As described later, a full-color color developing mode in which a plurality of single-color and single light- and heat-sensitive recording layers having different hues are laminated.

In the light and heat sensitive recording material of the present invention, each layer such as a light and heat sensitive recording layer, an intermediate layer and a protective layer described below may contain a binder. It can be appropriately selected from latexes and the like. Examples of the water-soluble polymer compound include methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, starch derivatives, casein, gum arabic, gelatin, ethylene-maleic anhydride copolymer,
Styrene-maleic anhydride copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, epichlorohydrin-modified polyamide, isobutylene-maleic salicylic anhydride copolymer, polyacrylic acid, polyacrylamide, etc. and modified products thereof Is mentioned.

Examples of the latex include styrene-butadiene rubber latex and methyl acrylate-
Butadiene rubber latex, vinyl acetate emulsion and the like. Among them, hydroxyethyl cellulose,
Preferred are starch derivatives, gelatin, polyvinyl alcohol derivatives, polyacrylamide derivatives and the like.

The light- and heat-sensitive recording material of the present invention may contain a pigment. The pigment includes known organic and inorganic pigments such as kaolin, calcined kaolin, talc and wax. Stone, diatomaceous earth, calcium carbonate, aluminum hydroxide, magnesium hydroxide, zinc oxide, lithopone, amorphous silica, colloidal silica, calcined stone, silica, magnesium carbonate, titanium oxide, alumina, barium carbonate, barium sulfate, mica , Microballoons, urea-formalin fillers, polyester particles, cellulose fillers and the like.

If necessary, various additives such as known waxes, antistatic agents, defoaming agents, conductive agents, fluorescent dyes, surfactants, ultraviolet absorbers and precursors thereof can also be used. .

In the light and heat sensitive recording material of the present invention, if necessary, a protective layer may be provided on the light and heat sensitive recording layer. Two or more protective layers may be laminated as necessary. Materials used for the protective layer include polyvinyl alcohol, carboxy-modified polyvinyl alcohol, vinyl acetate-acrylamide copolymer, silicon-modified polyvinyl alcohol, starch, modified starch, methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose,
Gelatin, gum arabic, casein, styrene-maleic acid copolymer hydrolyzate, styrene-maleic acid copolymer half ester hydrolyzate, isobutylene-maleic anhydride copolymer hydrolyzate, polyacrylamide derivative, polyvinylpyrrolidone And water-soluble polymer compounds such as sodium polystyrene sulfonate and sodium alginate; and latexes such as styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, methyl acrylate-butadiene rubber latex, and vinyl acetate emulsion.

The above-mentioned water-soluble polymer compound can be further improved in storage stability by crosslinking.
The crosslinking agent can be appropriately selected from known crosslinking agents, for example, a water-soluble initial condensate such as N-methylol urea, N-methylol melamine, urea-formalin; Aldehyde compounds; inorganic crosslinking agents such as boric acid and borax; and polyamide epichlorohydrin.

For the protective layer, known pigments, metal soaps, waxes, surfactants and the like can be further used. The coating amount of the protective layer is 0.2 to 5 in a dry coating amount.
preferably ^{g / m 2, 0.5~2g / m} 2 is more preferable. The thickness is preferably 0.2 to 5 μm,
0.5 to 2 μm is more preferable. When a protective layer is provided, a known ultraviolet absorber or a precursor thereof may be contained in the protective layer. The protective layer can be provided by the above-mentioned known coating method as in the case of forming the light and heat sensitive recording layer on the support.

As the support usable for the light- and heat-sensitive recording material of the present invention, any paper support used for ordinary pressure-sensitive paper or heat-sensitive paper, or dry or wet diazo copy paper can be used. For example, acid paper, neutral paper, coated paper, plastic film laminated paper, synthetic paper, and plastic films such as polyethylene terephthalate and polyethylene naphthalate can be used.

On the support, a back coat layer may be provided for the purpose of correcting the curl balance or for improving the chemical resistance from the back surface. The back coat layer can be provided in the same manner as the protective layer. Furthermore, if necessary, an antihalation layer is provided between the support and the light and heat sensitive recording layer, or on the surface of the support on which the light and heat sensitive recording layer is provided, and a slip layer is formed on the back surface thereof.
An antistatic layer, a pressure-sensitive adhesive layer and the like can be provided. Alternatively, a label may be formed by combining a release paper on the back surface of the support (the surface on the side where the photosensitive and heat-sensitive recording layer is not provided) with an adhesive layer interposed therebetween.

As described above, by using the diazonium salt of the present invention in the light- and heat-sensitive recording layer, a high color density can be obtained and high-speed light fixing can be performed. By increasing the light fixing speed, the recording time can be reduced, and since the diazonium salt itself is excellent in its decomposability, a sufficient fixing effect can be expected. Therefore, it is possible to prevent a decrease in whiteness due to coloring of a non-image portion (background portion), and it is possible to obtain a high-contrast image with little density fluctuation. That is, it is possible to realize both improvement in stability as a recording material and high speed. Further, by enclosing the diazonium salt in microcapsules, the long-term stability as a recording material can be further improved.

<Image Forming Method> Image formation using the light and heat sensitive recording material of the present invention may be performed by the following method. That is, for example, by heating and printing the surface of the light and heat sensitive recording material on the side where the light and heat sensitive recording layer is provided by a heating device such as a thermal head, the heating portion of the light and heat sensitive recording layer, A method in which a capsule wall containing polyurea and / or polyurethane is softened and becomes material-permeable, and when a coupler or a basic substance (organic base) outside the capsule enters the microcapsule, an image-like color is formed to form an image. It may be. In this case, after the color is formed, by further irradiating light corresponding to the absorption wavelength of the diazonium salt (light fixing), the diazonium salt causes a decomposition reaction and loses reactivity with the coupler, so that the image can be fixed. . By applying light fixing as described above, unreacted diazonium salt causes a decomposition reaction and loses its activity. Therefore, the density of the formed image fluctuates, and coloring occurs due to generation of stain in the non-image area (background area). That is, a decrease in whiteness and a decrease in image contrast due to the decrease can be suppressed.

Examples of the light source used for the light fixing include various fluorescent lamps, xenon lamps, mercury lamps, and the like. The light emission spectrum of these light sources should substantially match the absorption spectrum of the diazonium salt in the light and heat sensitive recording material. Is preferable in that fixing can be performed with high efficiency. In particular, in the present invention, the emission center wavelength of the irradiated light is 380 to 460 n
It is particularly preferred to use m light sources.

In addition, writing is performed imagewise by light,
It can also be used as a photo-writing heat-developing type thermosensitive recording material which forms an image by heat development. In this case, the printing process
A light source such as a laser is used instead of the above-described heating device.

In the light and heat sensitive recording material of the present invention, a multi-color light and heat sensitive recording material can be formed by laminating a plurality of light and heat recording layers having different coloring hues. Examples of the light and heat sensitive recording layer to be laminated include a light and heat sensitive recording layer containing a photodegradable diazonium salt. The multicolor photosensitive and heat-sensitive recording material is disclosed in JP-A-3-288.
No. 688, No. 4-135787, No. 4-14
No. 4784, No. 4-144785, No. 4-1
Nos. 94842, 4-24747, 4-
247448, 4-340540, 4
-340541, 5-34860, 5
No. 194842, Japanese Patent Application No. 7-316280, and the like.

For example, the layer constitution of the full-color photosensitive / thermosensitive recording material may be constituted as follows. However, the present invention is not limited to this. That is, two layers having different coloring hues, comprising two kinds of diazonium salts having different photosensitive wavelengths and being combined with a coupler capable of reacting with the respective diazonium salts upon heating to form different hues, and being contained in separate layers. A full-color photosensitive / thermosensitive recording material comprising a laminated photosensitive / thermosensitive recording layer (layer B, layer C) and a photosensitive / thermosensitive recording layer (layer A) in which an electron-donating colorless dye and an electron-accepting compound are combined. Alternatively, the photosensitive / thermosensitive recording layer may be a combination of the above two photosensitive / thermosensitive recording layers (B layer and C layer), a diazonium salt having a different photosensitive wavelength, and a coupler which reacts with the diazonium salt when heated to form a color. It may be a full-color light and heat sensitive recording material in which a recording layer (layer A) is laminated.

Specifically, an electron-donating colorless dye and an electron-accepting compound or a compound having a maximum absorption wavelength of 3
A first photosensitive and heat-sensitive recording layer (A layer) containing a diazonium salt shorter than 50 nm and a coupler which reacts with the diazonium salt to form a color when heated, and has a maximum absorption wavelength of 360 nm ± 20.
The second photosensitive and heat-sensitive recording layer (B layer) containing a diazonium salt having a wavelength of 400 nm and a coupler which reacts with the diazonium salt when heated to form a color, a diazonium salt having a maximum absorption wavelength of 400 ± 20 nm, Third light- and heat-sensitive recording layer (C layer) containing a coupler that develops a color upon reaction
May be sequentially laminated. In this case, a full-color image can be recorded by selecting the color hues of the photosensitive and heat-sensitive recording layers so as to be three primary colors, yellow, magenta, and cyan in the subtractive color mixing. As the layer configuration of the full-color recording material, yellow, magenta, and cyan color forming layers may be laminated in any manner.
From the viewpoint of the color reproducibility, it is preferable that yellow, cyan, magenta, or yellow, magenta, and cyan are stacked in this order from the support side.

A recording method in the case of a multicolor light and heat sensitive recording material can be performed, for example, as follows.
That is, first, the third light and heat sensitive recording layer (C layer) is heated,
The diazonium salt and the coupler contained in the layer are colored. Next, light of 400 ± 20 nm is irradiated to decompose unreacted diazonium salts contained in the C layer. Next, sufficient heat is applied to the second photosensitive and heat-sensitive recording layer (layer B) to develop color, and the diazonium salt and coupler contained in the layer are colored. At this time, the C layer is also heated strongly, but the diazonium salt has already been decomposed and the color forming ability has been lost, so that no color is formed. After this, 360 ± 20n
m is irradiated to decompose the diazonium salt contained in the B layer. Finally, heat is applied to the first photosensitive and heat-sensitive recording layer (A layer) to develop a color, and the color is developed. Then C
The layers B and B are also heated strongly at the same time, but the diazonium salt has already been decomposed and the color-forming ability has been lost, so that no color is formed. In the light and heat sensitive recording material of the present invention, it is preferable to use a multicolor light and heat recording material as described above.

As described above, the color-forming mechanism of the light- and heat-sensitive recording layer (layer A) directly laminated on the support surface may be a combination of an electron-donating dye and an electron-accepting dye, or a diazonium salt and the diazonium salt. It is not limited to a combination of a salt and a coupler which develops a color when reacted with heat, and develops a color by contacting with a basic compound to form a base, a chelate or a nucleophile to cause a elimination reaction. Any of a coloring system or the like may be used. By providing a light- and heat-sensitive recording layer containing a diazonium salt and a coupler that reacts with the diazonium salt and forms a color on the light- and heat-sensitive recording layer, a multicolor light and heat-sensitive recording material can be formed.

When a multi-color photosensitive / thermosensitive recording material is used, an intermediate layer may be provided between the respective photosensitive / thermosensitive recording layers in order to prevent color mixing between the photosensitive / thermosensitive recording layers. The intermediate layer is made of a water-soluble polymer compound such as gelatin, phthalated gelatin, polyvinyl alcohol, and polyvinylpyrrolidone, and may appropriately contain various additives.

When the light- and heat-sensitive recording material of the present invention is a multicolor light- and heat-sensitive recording material having a light-fixing light- and heat-sensitive recording layer on a support, if necessary, a light transmittance control may be further provided as an upper layer. It is desirable to provide a layer or a protective layer, or a light transmittance adjusting layer and a protective layer. The light transmittance adjusting layer is described in JP-A-9-39395 and JP-A-9-39.
396, Japanese Patent Application No. 7-208386, and the like. When a component that functions as a precursor of an ultraviolet absorber is used in the light transmittance adjustment layer, a high light transmittance is required before irradiation with light in a wavelength range necessary for fixing because the component does not function as an ultraviolet absorber. Therefore, when fixing the light-fixing type photosensitive heat-sensitive recording layer, it is possible to sufficiently transmit wavelengths in a region required for fixing and has a high visible light transmittance, which hinders fixing of the photosensitive heat-sensitive recording layer. Never.

On the other hand, the precursor of the ultraviolet absorber is irradiated with light in a wavelength region necessary for photo-fixing of the photo-fixing type photosensitive heat-sensitive recording layer (photo-decomposition of diazonium salt by light irradiation), and then reacted by the light. And act as an ultraviolet absorber. The ultraviolet absorber absorbs most of the light having a wavelength in the ultraviolet region, lowers the transmittance, and improves the light resistance of the light and heat sensitive recording material. However, since there is no absorption of visible light, the transmittance of visible light is not substantially changed. At least one light transmittance adjusting layer can be provided in the light and heat sensitive recording material, and particularly, it is preferably formed between the light and heat sensitive recording layer and the protective layer. Further, the function of the light transmittance adjusting layer may be imparted to the protective layer, and may be shared.

[0146]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In the examples, “parts” and “%” represent “parts by weight” and “% by weight”, respectively.

(Example 1) <Synthesis of diazonium salt A-1>: Exemplified compound A-1 4- (N-methyl-N-dodecylamino) -2- (2-
8.1 g of (chlorobenzyl) sulfonylaniline, 4.5 ml of concentrated hydrochloric acid and 40 ml of methanol were mixed, and the mixture was cooled to -5 ° C. To this mixture was added dropwise 4.0 ml of an aqueous solution in which 1.3 g of sodium nitrite was dissolved in water. Thereafter, the mixture was heated until the internal temperature of the mixture reached 10 ° C., and 4.1 g of potassium hexafluorophosphate was added thereto, followed by adding 2 g of potassium hexafluorophosphate.
The mixture was stirred at 0 ° C for 1 hour. Next, 20 ml of water was added, and the mixture was further stirred at 20 ° C. for 1 hour, and the precipitated crystals were collected by filtration, washed successively with water and isopropyl alcohol, and then dried. Recrystallized with a mixed solvent of 20 ml of ethyl acetate and 80 ml of isopropyl alcohol, collected by filtration,
After drying, 8.1 g of diazonium salt A-1 was obtained.

The obtained diazonium salt A-1 was identified by
^{This was performed by 1} H-NMR (solvent: CDCl ₃ , 300 MHz). The data is shown below. ¹ H-NMR (δ, ppm): 0.88 (t, J = 7.
5Hz, 3H), 1.16-1.40 (br, 18
H), 1.52-1.78 (br, 2H), 3.26 &
3.35 (s, 3H), 3.56 & 3.64 (t, J =
8Hz, 2H), 4.80 & 4.82 (s, 2H),
7.06 (dd, J = 10 & 2 Hz, 1H), 7.16
(D, J = 2 Hz, 1H), 7.28-7.52 (m,
4H), 8.18 (dt, J = 2 & 10 Hz, 1H) The maximum absorption wavelength λmax in methanol is 395
nm, and the molecular extinction coefficient ε was 2.57 × 10 ⁴ .

(Example 2) <Preparation of diazonium salt> In the same manner as in Example 1, diazonium salt A-1 (exemplified compound A-1) was synthesized.

<Preparation of microcapsule solution containing diazonium salt> To 20 parts of ethyl acetate, 2.7 parts of the diazonium salt A-1 obtained above and 9.2 parts of diphenylphthalate were added, and mixed uniformly. did. Next, 7.6 parts of a capsule wall material (Takenate D-110N, manufactured by Takeda Pharmaceutical Co., Ltd.) was added to and mixed with the mixed liquid to obtain a liquid I. Next, 46 parts of an 8% aqueous solution of phthalated gelatin, 1 part of water
7.5 parts, 1 part of sodium dodecylbenzenesulfonate
Solution I obtained above was added to a mixed solution of 2.5 parts of a 0% aqueous solution, and the mixture was subjected to 40 ° C. and 100 rpm using a homogenizer.
The mixture was emulsified and dispersed at 00 rpm for 10 minutes.

To the obtained emulsified dispersion, 20 parts of water was added and uniformly mixed, followed by microencapsulation at 40 ° C. for 3 hours with stirring to obtain a diazonium salt-encapsulated microcapsule solution. The average particle size of the microcapsules is 0.
It was 8 to 1.1 μm.

<Preparation of coupler emulsion> Ethyl acetate 1
In 0.5 part, 3 parts of a coupler (exemplified compound B-28), 2.8 parts of triphenylguanidine, 0.8 parts of tricresyl phosphate, and 0.5 part of diethyl maleate were dissolved,
Solution II was obtained. Next, a 15% aqueous solution of lime-processed gelatin 4
9 parts, 10% of sodium dodecylbenzenesulfonate
9.5 parts of an aqueous solution and 35 parts of water were mixed, and the resulting solution II was added to a mixed solution homogenized at 40 ° C., and the mixture was added at 40 ° C. and 10000 rpm using a homogenizer.
Emulsified and dispersed for 0 minutes. The obtained emulsified dispersion was stirred at 40 ° C. for 2 hours to remove ethyl acetate.
One part was added to obtain a coupler emulsion.

<Preparation of Coating Solution for Photosensitive and Thermosensitive Recording Layer> 3.6 parts of a diazonium salt-containing microcapsule solution, 3.3 parts of water
And 10.5 parts of a coupler emulsion were mixed to prepare a coating solution for a light and heat sensitive recording layer.

<Preparation of Coating Solution for Protective Layer> 100 parts of a 6% aqueous solution of itaconic acid-modified polyvinyl alcohol (KL-318; manufactured by Kuraray Co., Ltd.) and epoxy-modified polyamide (FL-71; manufactured by Toho Chemical Co., Ltd.) 30% dispersion 10
15 parts of a dispersion (hydrin Z; manufactured by Chukyo Yushi Co., Ltd.) of 40% zinc stearate was uniformly mixed with the mixed solution to prepare a coating solution D for a protective layer.

As a support, a photographic paper support obtained by laminating polyethylene on a high-quality paper was prepared, and a coating solution for a light and heat sensitive recording layer and a coating solution for a protective layer were applied on the photographic paper support with a wire bar in this order. After coating, drying was performed at 50 ° C. to obtain a light and heat sensitive recording material (1) of the present invention. The dry coating amounts of the light and heat sensitive recording layer and the protective layer were 8.0 g /
m ² , 1.6 g / m ² .

<Coloring test> A thermal head (KST type) manufactured by Kyocera Corporation was used to determine the voltage and pulse width applied to the thermal head so that the recording energy per unit area was 50 mJ / mm ^2. After forming an image by thermal printing from the protective layer of the material (1), the entire surface of the protective layer was irradiated with ultraviolet light for 20 seconds using an ultraviolet lamp having an emission center wavelength of 420 nm and an output of 40 W.
After the irradiation, the image density and the background density (density of the non-image part) of the color-developed part were measured. The usable range is 1.5 or higher in the density of the color forming portion, and 0.15 or lower in the non-image portion.

<Fixing test> The unprinted photosensitive and heat-sensitive recording material (1) was subjected to an emission center wavelength of 420 nm and an output of 40 W.
Irradiation was performed by using an ultraviolet lamp of No. 1 at 0.5 second intervals so as to increase the irradiation time sequentially to 20 seconds. After UV irradiation, the entire surface is made of Kyocera Corporation thermal head (KST type)
, And printing was performed at a constant heat energy, and the density of the colored portion after printing was measured in each region having different irradiation times. The irradiation time of the ultraviolet ray at which the color development stopped was defined as the fixing completion time.
The shorter the fixing completion time is, the faster the fixing speed is, and it is suitable for accelerating the image formation, which is preferable.

<Light Resistance Test> The colored portion and the background portion, which were colored using a thermal head (KST type) manufactured by Kyocera Corporation, were irradiated with a fluorescent lamp tester at 30,000 lux for 24 hours, and then the colored portion was exposed. And the density of the background part was measured. The lower the density in the color-developed portion after the fluorescent lamp irradiation and the lower the density in the background portion, the better the light resistance.

<Density Measurement> In each of the above-described tests, the density of the color-developed portion and the background was measured using a Macbeth densitometer (Macbeth densitometer).
th RD-918; manufactured by Macbeth Co., Ltd.)
The density of the background was also measured at the M position. The measured results are shown in Table 1 below.

Example 3 The present invention was carried out in the same manner as in Example 2 except that diazonium salt A-24 (exemplified compound A-24) was used instead of diazonium salt A-1 used in Example 2. The photosensitive and heat-sensitive recording material (2) was obtained. The diazonium salt A-24 was obtained in the same manner as in Example 1. Further, using the photosensitive and heat-sensitive recording material (2), a color development test, a fixing test, and a light resistance test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

Example 4 A light and heat sensitive recording material of the present invention was prepared in the same manner as in Example 2 except that the coupler of Example Compound B-29 was used in place of the coupler used in the coupler emulsion of Example 2. (3) was obtained. Using the photosensitive and heat-sensitive recording material (3), a color development test, a fixing test, and a light fastness test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

(Example 5) The diazonium salt A-1 used in Example 2 was replaced with a diazonium salt A-3 (exemplified compound A-
The light- and heat-sensitive recording material (4) of the present invention was prepared in the same manner as in Example 2 except that the coupler used in 3) and the coupler used in the coupler emulsion of Example 2 were replaced with a coupler of Exemplified Compound B-29. Obtained. The diazonium salt A-3 was prepared in Example 1.
Was obtained in the same manner as described above. Using the photosensitive and heat-sensitive recording material (4), a color development test, a fixing test, and a light fastness test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

Comparative Example 1 A light and heat sensitive recording material (5) was prepared in the same manner as in Example 2 except that the following diazonium salt C-1 was used in place of the diazonium salt A-1 used in Example 2. Obtained. Further, using a light and heat sensitive recording material (5),
A color development test, a fixing test, and a light fastness test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

Comparative Example 2 A light and heat sensitive recording material (6) was prepared in the same manner as in Example 2 except that the following diazonium salt C-2 was used in place of the diazonium salt A-1 used in Example 2. Obtained. Further, using a light and heat sensitive recording material (6),
A color development test, a fixing test, and a light fastness test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

Comparative Example 3 A light and heat sensitive recording material (7) was prepared in the same manner as in Example 2 except that the following diazonium salt C-3 was used in place of the diazonium salt A-1 used in Example 2. Obtained. Further, using a light and heat sensitive recording material (7),
A color development test, a fixing test, and a light fastness test were performed in the same manner as in Example 2, and the density was measured in the same manner as in Example 2. The measurement results are shown in Table 1 below.

[0166]

Embedded image

[0167]

[Table 1]

From the results shown in Table 1 above, in the heat-sensitive and heat-sensitive recording materials (1) to (4) of the present invention containing the diazonium salt of the present invention as a color-forming component, a sufficient color-forming density was obtained, and at the same time, the light was obtained in a short time. Fixing was completed, and high light resistance was obtained. That is, it was possible to achieve high-speed image formation, to form a high-contrast, robust image with excellent whiteness in the non-image area (background area), little density fluctuation in the image area. As described above, a diazonium salt having excellent photodegradability and a high decomposition rate was obtained. On the other hand, the light and heat sensitive recording materials (5) to which the diazonium salt of the present invention was not used were used.
In the case of (7), even when the light fixing was performed for a predetermined time, it was not possible to form an image having a small density fluctuation and sufficient light fastness. In addition, a decrease in contrast due to a decrease in whiteness of the non-image portion was also observed.

[0169]

According to the present invention, it is possible to provide a diazonium salt which is less likely to explode, has excellent photodegradability with respect to light in a wavelength region of 350 nm or more, and has a high decomposition rate. Also, while high color density can be obtained,
A light- and heat-sensitive recording material capable of high-speed light fixing, suppressing a decrease in whiteness due to coloring of a non-image portion (background portion), and forming a robust and high-contrast image with little density fluctuation. Can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03C 1/54 B41M 5/18 101S F term (Reference) 2H026 AA07 BB42 BB43 DD43 DD46 DD53 FF05 2H123 AC05 AC12 AC23 4H006 AA01 AA03 AB76 AB84 TA02

Claims (8)

[Claims] 1. A diazonium salt represented by the following general formula (I). Embedded image [Wherein, R ¹ and R ² each independently represent a hydrogen atom, an alkyl group or an aryl group, and R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom. R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ each independently represent a hydrogen atom, an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an acyloxy group, a carbamoyl group, an amide group , A cyano group, an alkylthio group, an arylthio group, an alkylsulfonyl group, or an arylsulfonyl group. X ^- represents an anion. However, at least one of R ⁵ , R ⁶ , R ⁷ , R ⁸ , and R ⁹ represents a halogen atom. ] 2. It is represented by the following general formula (II):
Diazonium salt. Embedded image[Wherein, R¹¹, R¹²Represents an alkyl group independently.
Then R¹³, R¹⁴Is independently a hydrogen atom, an alkyl
Represents a group or a halogen atom. Ar is represented by the following general formula (II)
Represents I), (IV) or (V). X^-Represents an anion
You. [Chemical formula 3][Wherein, R¹⁶, R¹⁷, R¹⁸Are independently hydrogen sources
, Alkyl group, aryl group, halogen atom, alkoxy
Represents a silyl group or an aryloxy group. R^{twenty five}, R²⁷, R ²⁸, R
²⁹Is independently a hydrogen atom, an alkyl group, an aryl
Group, halogen atom, alkoxy group, aryloxy group
Represents, R^{twenty five}And R²⁹At least one of them represents a hydrogen atom
You. R³⁵, R³⁶, R³⁸Are each independently a hydrogen atom,
Alkyl group, aryl group, alkoxy group, aryloxy
Represents a group. ] 3. A diazonium salt represented by the following general formula (VI). Embedded image [Wherein, R ²¹ and R ²² each independently represent an alkyl group, and X ⁻ represents an anion. ] 4. A light and heat sensitive recording material having a light and heat sensitive recording layer containing a diazonium salt and a coupler on a support, wherein the diazonium salt is the diazonium salt according to any one of claims 1 to 3. Characteristic heat and heat sensitive recording material. 5. The light and heat sensitive recording material according to claim 4, wherein the diazonium salt is encapsulated in microcapsules. 6. The light and heat sensitive recording material according to claim 5, wherein the capsule wall of the microcapsule contains polyurethane and / or polyurea as a component. 7. The light and heat sensitive recording material according to claim 4, wherein the coupler is a compound represented by the following formula (VII) or a tautomer thereof. Embedded image [In the formula, E ¹ and E ² each independently represent an electron-withdrawing group, and E ¹ and E ² may combine to form a ring. ] 8. The light and heat sensitive recording material according to claim 4, wherein the light and heat sensitive recording layer contains an organic base.