JPH08310133A - Diazo thermal recording material - Google Patents

Abstract

PURPOSE: To enhance the light fastness of an image part and a background part after recording, in a diazo thermal recording material wherein a recording layer containing a diazonium salt compd., a coupling component and an org. base is provided on a support, by using a compd. having a specific substituent as the diazonium salt compd. CONSTITUTION: In a diazo thermal recording material high in the light fastness of an image after recording and reduced in the coloration of a background part at a time of the irradiation with light after recording and obtained by providing a recording layer containing a diazonium salt compd., a coupling component and an org. base on a support, a diazonium salt compd. represented by formula (wherein R1 -R5 are a substituted or non-substituted alkyl group, aralkyl group or aryl group, R2 and R3 or R4 and R5 may form a ring along with a nitrogen atom and X is an acid anion) is used and is pref. microencapsulated.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a recording material utilizing the photosensitivity of a diazonium salt. More specifically, it relates to a diazo heat-sensitive recording material which forms a color image composed of a diazonium salt compound, a coupling component, and a base.

[0002]

2. Description of the Related Art As recording materials utilizing the photosensitivity of diazonium salt compounds, there are roughly three types known. One is the type known as wet development type,
A photosensitive layer containing a diazonium salt compound and a coupling component as a main component is provided on a support, and this material is superposed on an original and exposed and developed with an alkaline solution. The second is a type known as dry development type,
Unlike the wet type, development is performed with ammonia gas. The third type is known as a heat development type, which contains a type of ammonia gas generating agent such as urea that can generate ammonia gas by heating in the photosensitive layer and trichloroacetic acid in the photosensitive layer. There are a type containing an alkali salt of an acid that loses its properties as an acid by various heating, a type utilizing activation of a diazonium salt compound and a coupling component by heating and melting using a higher fatty acid amide as a color forming aid.

The wet type requires a replenishment and disposal of a liquid because it uses a developing solution, has a large size of the apparatus, and has other maintenance problems. There are some problems such as not being present or the copied image being intolerable to long-term storage. Also, the dry type requires replenishment of the developing solution as well as the wet type, a gas absorption facility is required to prevent the generated ammonia gas from leaking to the outside, and thus the device becomes large, and so on. It has a problem such as smell of ammonia immediately after copying. On the other hand, unlike the wet type and dry type, the heat development type has an advantage in maintenance because it does not require a developing solution, but all the conventionally known types require a high development temperature of 150 ° C to 200 ° C. In addition, if the temperature is not controlled to about ± 10 ° C., there is a problem that the development cost becomes insufficient and the color tone changes, resulting in a high apparatus cost. Further, the diazonium salt compound used for such high temperature development also needs to have high heat resistance, but such a compound is often disadvantageous for forming a high concentration. Low temperature development (9
Although many attempts have been made at 0 ° C. to 130 ° C., there has been a drawback that the shelf life of the material itself is shortened. As described above, the heat-development type is expected to have a merit in maintenance as compared with the wet type and the dry type, but is not yet the mainstream of the diazo recording system.

Further, by utilizing the property of decomposing by light and losing activity, it has recently been applied to a recording material which is required to fix an image. As a typical example, a diazonium salt compound and a coupling component are heated by heat. A photo-fixing type heat-sensitive recording material has been proposed in which an image is formed by reacting and then irradiated with light to fix the image (Koji Sato et al., The Institute of Image Electronics Engineers of Japan, No. 1).
Vol. 1, No. 4, (1982) p290-296). However, these recording materials using a diazonium salt compound as a color-forming element have a very high activity of the diazonium salt compound, so that even in the dark, the diazonium salt compound gradually undergoes thermal decomposition and loses its reactivity. In the case of, the phenomenon that the background part is colored or the color density is reduced during storage before copying, and the color density of the image part is reduced and the coloration of the non-image part is increased with the light fixing type heat-sensitive recording material. There is a problem that the shelf life is short when used as a material.

In the case of both the heat-developing diazo copy and the heat-developable light-fixing type heat-sensitive recording material, it is impossible to design a material capable of sufficiently developing color and obtaining a high density even at a low heating temperature. As a matter of course, a coloring reaction may occur even during storage at room temperature before image formation, and it appears as a phenomenon in which the background portion that must be white is colored.
In particular, in the case of a red-coloring type recording material, there is a problem that even a slight background coloring (fogging) is conspicuous because of high visibility. As a means for solving these problems, in a recording material provided with a photosensitive layer containing a diazonium salt compound, a coupling component and a basic substance on a support, the diazonium salt compound is contained in microcapsules. Furthermore, investigations have been made from the viewpoints of searching for basic substances and making microcapsules (JP-A-2-54251). Further, as the diazonium salt compound, a 4-substituted amino-2-alkoxybenzenediazonium salt having a specific substituent is excellent in the preservability (raw preservability) before recording, and a specific coupling component (barbitur In combination with an acid derivative), it has been reported that the image light resistance is excellent (Japanese Patent Application No. 5-278608). However, even the recording material prepared using this diazonium salt compound has not reached a sufficiently satisfactory level of light resistance of the image after recording. Further, there is a drawback that the background portion, which must be white, is colored when irradiated with light after recording. As a result of intensive investigations by the present inventors for the purpose of solving this drawback, the inventors have found that a diazonium salt compound having a specific substituent exhibits excellent performance, and arrived at the present invention.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a diazo heat-sensitive recording material which has a high light resistance of the image after recording in the diazo heat-sensitive recording material and has less coloring of the background portion upon irradiation with light after the recording. To provide.

[0007]

The above objects of the present invention are as follows.
In a diazo heat-sensitive recording material in which a recording layer containing a diazonium salt compound, a coupling component and an organic base is provided on a support, the diazonium salt compound represented by the following general formula (I) is used. Achieved with a diazo thermosensitive recording material. General formula (I)

[0008]

Embedded image

In the formula, R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are
It represents a substituted or unsubstituted alkyl group, aralkyl group or aryl group. R ₂ and R ₃ or R ₄ and R ₅ may form a ring together with a nitrogen atom. X represents an acid anion.

In the general formula (I), R ₁ , R ₂ ,
The group represented by R ₃ , R ₄ and R ₅ has 1 to 18 carbon atoms.
Are preferred, an aralkyl group having 7 to 21 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, which may further have a substituent.

In the general formula (I), R ₁ , R ₂ ,
When R ₃ , R ₄ and R ₅ have a substituent, the substituent is an alkyl group, an aryl group, a hydroxy group, an alkyloxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyl group, an alkoxycarbonyl group or an acyloxy group. Group, carbamoyl group, acylamino group, halogen atom, cyano group and the like.

In the general formula (I), R ₁ , R ₂ ,
In the case where R ₃ , R ₄ and R ₅ have a substituent, as a substituent, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 20 carbon atoms, a hydroxy group, an alkyloxy group having 1 to 18 carbon atoms, Arylalkyl group having 6 to 20 carbon atoms, 1 carbon atom
-18 alkylthio group, C6-20 arylthio group, C2-25 alkylcarbonyl group, C7-35 arylcarbonyl group, C2-25 alkoxycarbonyl group, C2-20 Acyloxy group, C2-C37 carbamoyl group, C2-C35
The acylamino group, the halogen atom and the cyano group are preferable.

In the general formula (I), R ₁ , R ₂ ,
From the viewpoint of oil solubility, the total carbon number of R ₃ , R ₄ , and R ₅ is preferably 12 or more, and particularly preferably 14 or more.

In the general formula (I), specific examples of the acid of the acid anion represented by X include the followings.

Polyfluoroalkylcarboxylic acid having 1 to 9 carbon atoms, polyfluoroalkylsulfonic acid having 1 to 9 carbon atoms, boron tetrafluoride, tetraphenylboron, hexafluorophosphoric acid, aromatic carboxylic acid, aromatic It is also possible to stabilize the diazonium salt by forming a complex compound using sulfonic acid, zinc chloride, cadmium chloride, tin chloride or the like.

The diazonium salt compound according to the present invention preferably has a melting point of 30 ° C to 200 ° C, but is preferably 50 ° C to 150 ° C from the viewpoint of handling.

Further, the diazonium salt compound of the present invention is more preferably used by being encapsulated in microcapsules for the purpose of preventing precoupling, but in the case of forming microcapsules, a suitable solvent (eg tricresyl phosphate) is used.
Since it is used after being dissolved in, it is desirable that it has an appropriate solubility in these solvents. Specifically, it is preferable that the solvent has a solubility of 5% or more. Further, the water solubility is preferably 1% or less.

The diazonium salt compound according to the present invention is preferably used in the heat-sensitive recording layer in an amount of 0.02 to 3 g / m ² , and in view of color density, 0.1 to ² g / m ^2.
It is more preferable to use the above range.

Specific examples of the diazonium salt compound according to the present invention are shown below, but the present invention is not limited thereto.

2- (n-hexyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2
-(2-phenoxyethyl) oxy-4-bis [di (n
-Hexyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2
-Ethoxyethyl) oxy-4-bis [di (n-hexyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (1-methylpropyl) oxy-4-bis [di (n-butyl) aminocarbonyl Methyl] aminobenzenediazonium hexafluorophosphate, 2- (1-ethylpropyl)
Oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2-ethylhexyl) oxy-4
-Bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2-neopentyloxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazo
Aluminum hexafluorophosphate, 2- (i-butyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate,

2- (3-ethoxycarbonylpropyl)
Oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (cyclohexylmethyl) oxy-
4-bis [di (n-butyl) aminocarbonylmethyl]
Aminobenzenediazonium hexafluorophosphate, 2- (n-octyl) oxy-4-bis [di (n
-Butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-
Dodecyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-hexadecyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] amino Benzenediazonium hexafluorophosphate, 2- (n-butyl) oxy-4-bis [di (isobutyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2-
(N-hexyl) oxy-4-bis [di (isobutyl)
Aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2-ethylhexyl) oxy-4-bis [di (isobutyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-butyl) oxy- 4-
Bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-butyl) oxy-4-bis [di (n-hexyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate 2- (n-butyl) oxy-4-bis [di (n-octyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate,

2- (n-hexyl) oxy-4-bis [di (n-hexyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate,
2- [2- (2,5-di-t-amylphenoxy) ethyl] oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- [2- (2 , 5-Di-t-amylphenoxy) ethyl] oxy-4-bis (pyrrolidinocarbonylmethyl) aminobenzenediazonium hexafluorophosphate, 2- [2- (2,5-di-t
-Amylphenoxy) ethyl] oxy-4-bis (piperidinocarbonylmethyl) aminobenzenediazonium hexafluorophosphate, 2- [2- (2,5-
Di-t-amylphenoxy) ethyl] oxy-4-bis (morpholinocarbonylmethyl) aminobenzenediazonium hexafluorophosphate, 2- (n-butyl) oxy-4-bis [(N-ethyl-N-phenyl)
Aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-hexyl)
Oxy-4-bis [(N-ethyl-N-phenyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate,

2- (n-hexyl) oxy-4-bis [(N-isopropyl-N-phenyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2-ethylhexyl) oxy-
4-bis [(N-isopropyl-N-phenyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-dodecyl) oxy-4-bis [di (2-methoxyethyl) aminocarbonylmethyl] amino Examples thereof include benzenediazonium hexafluorophosphate and 2- (n-dodecyl) oxy-4-bis [(N-methyl-N-ethoxycarbonylmethyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate. The diazonium salt compound according to the present invention may be used alone,
Alternatively, two or more kinds can be used in combination.

The diazonium salt compound used in the present invention is preferably encapsulated in microcapsules. The forming method can be carried out using a known method. Below is a brief description. First, the above diazonium salt compound is dissolved or dispersed in an appropriate organic solvent, and then this solution or dispersion (oil liquid) is emulsified and dispersed in an aqueous medium. The diazonium salt compound of the present invention used for this purpose more preferably has a suitable solubility in an organic solvent. Examples of the organic solvent include phosphoric acid esters, phthalic acid esters, carboxylic acid esters, fatty acid amides, alkylated biphenyls, alkylated terphenyls, chlorinated paraffins, alkylated naphthalenes, carbonates, and diarylethanes.

Next, a wall made of a polymer material is formed around the emulsified and dispersed oil droplets. Reactants for forming polymeric substances are added to oily liquids and / or aqueous media. The polymer substance forming the capsule wall is impermeable at room temperature and needs to be permeable at the time of heating, and it is particularly preferably one having a glass transition temperature of 60 to 200 ° C. Examples thereof include polyurethane, polyurea, polyamide, polyester, urea / formaldehyde resin, melamine resin, polystyrene, styrene / methacrylate copolymer, styrene / acrylate copolymer, and mixed systems thereof.

Interfacial polymerization and internal polymerization are suitable as the microcapsule forming method. Details of the capsule forming method and specific examples of the reactant are described in US Pat. Nos. 3,726,804 and 3,796,669. For example, when polyurea polyurethane is used as a capsule wall agent, polyisocyanate and a second substance (for example, polyol, polyamine) which reacts with it to form a capsule wall are mixed in an aqueous medium or an oily liquid to be encapsulated, Then, these are emulsified and dispersed, and then heated, whereby a polymer forming reaction occurs at the oil droplet interface to form a microcapsule wall. An auxiliary solvent having a low boiling point and a strong dissolving power may be added to the oily liquid. Polyurea is produced even when the addition of the second substance is omitted.

Further, when forming microcapsules, a water-soluble polymer compound can be used as a protective colloid. Examples of the water-soluble polymer compound include a water-soluble anionic polymer compound, a nonionic polymer compound and an amphoteric polymer compound. These water-soluble polymer compounds are used as 0.01 to 10% by weight aqueous solution.

The coupling component according to the present invention includes
It produces a color by causing a coupling reaction with the diazonium salt compound in a basic atmosphere, and can be selected according to the desired hue. Specific examples of these are:
For example, resorcin, phloroglucin, sodium 2,3-dihydroxynaphthalene-6-sulfonate, sodium 2-hydroxy-3-naphthalenesulfonate, 2-hydroxy-3-naphthalenesulfonic acid anilide, 2-hydroxy-3-naphthalenesulfonic acid morpholino Amide, 2-hydroxy-3-naphthalenesulfonic acid morpholinopropylamide, 2-hydroxy-3-naphthalenesulfonic acid (2-ethylhexyl) oxypropylamide, 2-hydroxy-3-naphthalenesulfonic acid (2-
Ethylhexyl) amide, 1-hydroxy-8-acetylaminonaphthalene-3,6-disulfonic acid sodium salt, 1-hydroxy-8-acetylaminonaphthalene-
3,6-Disulfonic acid dianilide, 1-hydroxy-2
-Naphthoic acid morpholinopropylamide, 1,5-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-hydroxy-3-naphthoic acid anilide,
2-Hydroxy-3-naphthoic acid-2'-methylanilide, 2-hydroxy-3-naphthoic acid ethanolamide, 2-hydroxy-3-naphthoic acid (n-octyl)
Amide, 2-hydroxy-3-naphthoic acid morpholinoethylamide, 2-hydroxy-3-naphthoic acid piperidinoethylamide, 2-hydroxy-3-naphthoic acid piperidinopropylamide,

2-Hydroxy-3-naphthoic acid (n-dodecyloxy) propylamide, 2-hydroxy-3-
Naphthoic acid (n-tetradecyl) amide, 6-methoxy-2-hydroxy-3-naphthoic acid anilide, 6-ethoxy-2-hydroxy-3-naphthoic acid anilide, 6-
Methoxy-2-hydroxy-3-naphthoic acid morpholinopropylamide, 6-methoxy-2-hydroxy-3-
Naphthoic acid (2-hydroxy) ethylamide, acetanilide, acetoacetanilide, 2,5-di (n-heptyloxy) acetoacetanilide, benzoylacetanilide, 1-phenyl-3-methyl-5-pyrazolone, 1- (2 ', 4 ', 6'-Trichlorophenyl)-
3-benzamido-5-pyrazolone, 1- (2 ',
4 ', 6'-trichlorophenyl) -3-anilino-5
-Pyrazolone, 1-phenyl-3-phenylacetamide-5-pyrazolone, 1-methyl-3-phenyl-2,
4,6,-(1H, 3H, 5H) -pyrimidinetrione, 1-[(n-octadecyl) oxypropyl] -3
-Phenyl-2,4,6,-(1H, 3H, 5H) -pyrimidinetrione, 1-phenyl-3- [2,5-di (n-octyloxy) phenyl] -2,4,6,-
(1H, 3H, 5H) -Pyrimidinetrione, 1,3-
Di [2,5-di (n-octyloxy) phenyl]-
2,4,6,-(1H, 3H, 5H) -pyrimidinetrione, 1,3-di [(n-octadecyl) oxycarbonylmethyl] -2,4,6,-(1H, 3H, 5H)-
Pyrimidinetrione, 5,5-dimethylcyclohexane-1,3-dione, 5- [2- (n-tetradecyloxy) phenyl] cyclohexane-1,3-dione, N-
[(2-Ethylhexyl) oxypropyl] -3-cyano-4-ethyl-6-hydroxy-2-pyridone, N-
[(N-Dodecyl) oxypropyl] -3-acetyl-
4-methyl-6-hydroxy-2-pyridone etc. can be mentioned.

These coupling components may be used alone or in combination of two or more.

In the present invention, an organic base is added for the purpose of making the system basic during heat development and promoting the coupling reaction. These organic bases may be used alone or in combination of two or more. Examples of the basic substance include nitrogen-containing compounds such as tertiary amines, piperidines, piperazines, amidines, formamidines, pyridines, guanidines and morpholines.

[0032] Especially, 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 ^'- bis [3- (beta-
Naphthoxy) -2-hydroxypropyl] piperazine,
N-3- (beta-naphthoxy) -2-hydroxypropyl -N ^'- methylpiperazine, 1,4-bis {[3- (N
-Methylpiperazino) -2-hydroxy] propyloxy} benzene and other piperazines, N- [3- (β-naphthoxy) -2-hydroxy] propylmorpholine,
Morpholines such as 1,4-bis [(3-morpholino-2-hydroxy) propyloxy] benzene and 1,3-bis [(3-morpholino-2-hydroxy) propyloxy] benzene, N- (3-phenoxy) Specifically, piperidines such as 2-hydroxypropyl) piperidine and N-dodecylpiperidine, and guanidines such as triphenylguanidine, tricyclohexylguanidine, and dicyclohexylphenylguanidine are specifically preferable.

In the present invention, the diazonium salt compound 1
It is preferable to use the coupling component in an amount of 0.1 to 30 parts by weight and the basic substance in an amount of 0.1 to 30 parts by weight based on parts by weight.

In the present invention, in addition to the organic base, a color forming auxiliary agent can be added for the purpose of promoting the color forming reaction. As the coloring aid, for example, a sulfonamide compound, a phenol derivative, a bisphenol derivative, a naphthol derivative, a hydroxy compound such as phenylbenzyl alcohol, and an amide compound such as carboxylic acid amide can be added. These compounds prevent the deterioration of the image quality due to the precipitation of the materials constituting the emulsion during storage, or improve the heat permeability of the microcapsule wall, resulting in a high color density. There is.

The coupling component used in the present invention is
With a basic substance, other coloring aids, etc., it can also be used by solid-dispersing it together with a water-soluble polymer by a sand mill or the like, but after dissolving it in an organic solvent that is sparingly soluble or insoluble in water, it is used as a surfactant and It is preferable to mix it with an aqueous phase having a water-soluble polymer as a protective colloid to prepare an emulsion dispersion. From the viewpoint of facilitating emulsion dispersion, it is preferable to use a surfactant.

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

An auxiliary solvent may be added to the above organic solvent as a dissolution aid having a low boiling point. As such an auxiliary solvent, for example, ethyl acetate, isopropyl acetate, butyl acetate, methylene chloride and the like can be mentioned as particularly preferable ones. In some cases, it is possible to use only the low boiling auxiliary solvent without the high boiling oil.

The water-soluble polymer to be contained as a protective colloid in the aqueous phase mixed with the oil phase containing these components is
It can be appropriately selected from known anionic polymers, nonionic polymers, and amphoteric polymers. Examples of preferable water-soluble polymers include polyvinyl alcohol, gelatin, cellulose derivatives and the like.

The surfactant contained in the aqueous phase may be appropriately selected from anionic or nonionic surfactants which do not cause precipitation or aggregation by acting on the protective colloid. it can. Preferred surfactants include sodium alkylbenzene sulfonate, sodium alkylsulfate, dioctyl sodium sulfosuccinate, polyalkylene glycol (eg, polyoxyethylene nonylphenyl ether), and the like.

To the recording material of the present invention, a free radical generator (a compound capable of generating a free radical upon irradiation with light) used in a photopolymerizable composition or the like for the purpose of reducing yellowing of the background after copying is added. be able to. Examples of the free radical generator include aromatic ketones, quinones, benzoin, benzoin ethers, azo compounds, organic disulfides, acyloxime esters and the like. The amount of the free radical generator to be added is preferably 0.01 to 5 parts by weight with respect to 1 part by weight of the diazonium salt compound.

Similarly, for the purpose of reducing yellowing, a polymerizable compound having an ethylenically unsaturated bond (hereinafter referred to as vinyl monomer) can be used. The 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 monomer or prepolymer. Examples thereof include unsaturated carboxylic acids and salts thereof, esters of unsaturated carboxylic acids with aliphatic polyhydric alcohols, amides of unsaturated carboxylic acids with aliphatic polyhydric amine compounds, and the like. The vinyl monomer is used in a proportion of 0.2 to 20 parts by weight with respect to 1 part by weight of the diazo compound.

The above-mentioned free radical generator and vinyl monomer may be contained in a microcapsule together with a diazonium salt compound for use.

In the present invention, in addition to the above materials, citric acid, tartaric acid, oxalic acid, boric acid, phosphoric acid, pyrophosphoric acid and the like can be added as an acid stabilizer. Further, methyl p-toluenesulfonate, dibutyl sulfate and the like, which are decomposed into an acid, can be added.

For the recording material of the present invention, a coating liquid containing a microcapsule containing a diazonium salt compound, a coupling component, an organic base and other additives is prepared, and the recording material of a support such as paper or a synthetic resin film is prepared. Apply bar on top,
Solid content of 2.5 after coating and drying by coating methods such as blade coating, air knife coating, gravure coating, roll coating, spray coating, dip coating, and curtain coating.
Provide a photosensitive layer of about 30 g / m ² .

In the recording material of the present invention, the microcapsules, the coupling component, the base and the like may be contained in the same layer as described in the above method, or may be contained in a separate layer. Can also be taken. It is also possible to apply a photosensitive layer after providing an intermediate layer described in JP-A-61-54980 on a support.

As the support of the present invention, any paper support used for ordinary pressure-sensitive paper, thermal paper, dry or wet diazo copying paper, etc. can be used, and also neutral ones such as alkyl ketene dimer. Neutral paper having a pH of 5 to 9 sized with a sizing agent (as described in JP-A-55-14281), satisfying the relationship between the Steckigt sizing degree and the metric basis weight described in JP-A-57-116687, and Paper having a Beck's smoothness of 90 seconds or more, the optical surface roughness described in JP-A-58-136492 of 8 μm or less, and the thickness of 30 to 30.
150 μ paper, paper having a density of 0.9 g / cm ³ or less as described in JP-A-58-69091 and an optical contact ratio of 15% or more, Canadian standard freeness (JP-A-58-69097). Paper made from pulp that has been beaten to 400 cc or more in accordance with JIS P8121) to prevent soaking of the coating liquid,
A base paper produced by the Yankee machine described in JP-A-58-65695 is used as a coating surface to improve color density and resolution. A base paper described in JP-A-59-35985 is subjected to corona discharge treatment. It is also possible to use paper having improved coating suitability.

Further, the synthetic resin film used as the support in the present invention can be arbitrarily selected from known materials which are not deformed by heating in the developing process and have dimensional stability. Examples of such a film include polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate film, polystyrene films, polypropylene films, polyolefin films such as polyethylene, and the like, which may be used alone or in combination. Can be used. The thickness of the support used is 20 to 200 μm.

When an image is formed on the recording material of the present invention,
The following method can be used. One is a method of exposing a document to form a latent image, fixing the image by irradiating the area other than the image forming portion, and then performing thermal development. The other is a thermal pen or thermal head. After a color image is obtained by heat such as heat, the area other than the image area is irradiated with light to fix the image. Either method can be preferably used. As the light source for exposure, various fluorescent lamps, xenon lamps, mercury lamps, etc. are used, and if the emission spectrum is almost the same as the absorption spectrum of the diazonium salt compound used in the recording material, the parts other than the image forming part can be efficiently used. It is preferable because it can be fixed by light. Further, in the step of heating the material to develop or develop color, as a heating means, a hot pen, a thermal head, infrared rays, high frequency,
A heat block, a heat roller, etc. can be used.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. All "parts" in the examples represent parts by weight.

[0050]

【Example】

Example 1 [Preparation of capsule liquid A of the present invention]: 2- (n-octyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate 2 in 19 parts of ethyl acetate 0.8 parts and 10 parts of tricresyl phosphate were added and mixed uniformly.
Next, Takenate D-110N as a wall agent was added to this mixed solution.
(Takeda Pharmaceutical Co., Ltd.) Add 7.6 parts and mix evenly.
A liquid was obtained. Next, to this solution I were added 46.1 parts of an 8% by weight aqueous solution of phthalated gelatin, 17.5 parts of water, and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate, and the mixture was added at 40 ° C.
It was emulsified and dispersed at 10,000 rpm for 10 minutes. 20 parts of water was added to the obtained emulsion to homogenize it, and then 4 with stirring.
Capsule liquid A was obtained by carrying out an encapsulation reaction at 0 ° C. for 3 hours. The particle size of the capsule was 0.35 μm.

[Preparation of coupling component / base emulsion B]: 1 part of 1-phenyl-3- [2,5-
Di (n-octyloxy) phenyl] -2,4,6,-
2.4 parts of (1H, 3H, 5H) -pyrimidinetrione,
3.2 parts of 4- (2-ethylhexyloxy) phenylsulfonamide, 2.5 parts of triphenylguanidine, 0.64 parts of tricresyl phosphate and 0.32 parts of maleic acid diethyl ester were dissolved to obtain a liquid II. Next, 32 parts of a 15% by weight aqueous solution of lime-processed gelatin, 5 parts of a 10% aqueous solution of sodium dodecylbenzene sulfonate, and 30 parts of water were added to 4 parts.
The liquid II was added to the mixture uniformly mixed at 0 ° C., and the mixture was emulsified and dispersed at 40 ° C. and 10,000 rpm for 10 minutes using a homogenizer. The obtained emulsion was stirred at 40 ° C. for 2 hours to remove ethyl acetate, and the weight of volatilized ethyl acetate and water was supplemented with water to obtain a coupling component / base emulsion B.

[Preparation of coating liquid C]: 6 parts of capsule liquid A,
4.4 parts of water, 15% by weight aqueous solution of lime-processed gelatin
After uniformly mixing 9 parts at 40 ° C., 8.3 parts of coupler / base emulsion B was added and uniformly mixed to obtain coating solution C for heat-sensitive recording layer. [Preparation of protective layer coating solution D]: 32 parts of a 10% aqueous solution of polyvinyl alcohol (polymerization degree: 1700, saponification degree: 88%) and 36 parts of water were uniformly mixed to obtain a protective layer coating solution D.

[Coating]: The coating solution C for the heat-sensitive recording layer and the coating solution D for the protective layer were successively coated with a wire bar on a support for printing paper, which was obtained by laminating polyethylene on a high-quality paper, and then at 50 ° C.
Then, the desired diazo thermosensitive recording material was obtained. The coating amount as solid content is 6.4 g / m ² and 1.05, respectively.
It was g / m ² .

[Test of color development and fixing]: Using a thermal head (KST type) manufactured by Kyocera Corporation, the applied power and pulse width to the thermal head were set so that the recording energy per unit area was 0 to 40 mJ / mm ^2. After heat-printing on the determined diazo heat-sensitive recording layer to obtain an image, the whole surface was irradiated with light for 15 seconds using an ultraviolet lamp having an emission center wavelength of 365 nm and an output of 40 W. The densities of the image part and the background part of the obtained sample were measured with a Macbeth densitometer.

[Light resistance test]: The above-described color-developed and fixed sample was continuously irradiated with light for 3 hours with a 32,000 LUX fluorescent lamp light resistance tester to perform a discoloration test for image areas and background areas.
For the image density measurement, a Macbeth densitometer was used to examine the density change in which the initial reflection density was about 1.1.

Examples 2-5 Instead of the diazonium salt compound used in Example 1, 2- (1-methylpropyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium was prepared, respectively. Hexafluorophosphate, 2-
(1-Ethylpropyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2-ethylhexyl) oxy-4-bis [di (n-butyl) amino Carbonylmethyl] aminobenzenediazonium hexafluorophosphate and 2- (cyclohexylmethyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate were used to obtain a capsule liquid. The same operation as in Example 1 was performed.

Example 6 Instead of the coupling component used in Example 2, 1-
[(N-Octadecyl) oxypropyl] -3-phenyl-2,4,6,-(1H, 3H, 5H) -pyrimidinetrione was used, and the coupling component / base emulsion was obtained to obtain Example 2. The same operation was performed.

Examples 7 to 8 2- (1-ethylpropyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium was used instead of the diazonium salt compound used in Example 6, respectively. Hexafluorophosphate, 2-
(2-Ethylhexyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium The same operation as in Example 6 was carried out except that a capsule liquid was obtained using hexafluorophosphate.

Comparative Examples 1 and 2 Instead of the diazonium salt compound used in Example 1, 2- (n-hexyl) oxy-4- <N- [1-methyl-2- (4-methoxyphenoxy) was used. ] Ethyl, N-
n-hexyl> aminobenzenediazonium hexafluorophosphate, 2- (n-hexyl) oxy-4
-[N- (1-methyl-2-phenoxy) ethyl, N-
n-Hexyl] aminobenzenediazonium Hexafluorophosphate was used and the same operation as in Example 1 was performed except that a capsule liquid was obtained.

Comparative Example 3 Instead of the diazonium salt compound used in Example 6, 2
-(N-hexyl) oxy-4- <N- [1-methyl-
2- (4-Methoxyphenoxy)] ethyl, Nn-hexyl> aminobenzenediazonium Hexafluorophosphate was used to obtain a capsule liquid, and the same operation as in Example 6 was performed.

Table 1 shows the results of the image density and background density measurements.

[0062]

[Table 1]

Example 9 [Preparation of capsule liquid A of the present invention]: 2- (n-hexyl) oxy-4-bis [di (n-butyl) aminocarbonylmethyl] aminobenzenediazonium hexafluoro in 19 parts of ethyl acetate 2.8 parts of phosphate and 10 parts of tricresyl phosphate were added and mixed uniformly.
Next, Takenate D-110N as a wall agent was added to this mixed solution.
(Takeda Pharmaceutical Co., Ltd.) Add 7.6 parts and mix evenly.
A liquid was obtained. Next, to this solution I were added 46.1 parts of an 8% by weight aqueous solution of phthalated gelatin, 17.5 parts of water, and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate, and the mixture was added at 40 ° C.
It was emulsified and dispersed at 10,000 rpm for 10 minutes. 20 parts of water was added to the obtained emulsion to homogenize it, and then 4 with stirring.
Capsule liquid A was obtained by carrying out an encapsulation reaction at 0 ° C. for 3 hours. The particle size of the capsule was 0.35 μm.

[Preparation of coating liquid E]: 6 parts of capsule liquid A,
4.4 parts of water, 15% by weight aqueous solution of lime-processed gelatin
Coating liquid E was obtained by uniformly mixing 9 parts at 40 ° C. [Preparation of protective layer coating solution F]: 32 parts of a 10% aqueous solution of polyvinyl alcohol (polymerization degree: 1700, saponification degree: 88%) and 36 parts of water were uniformly mixed to obtain a protective layer coating solution F.

[Coating]: Coating solution E and coating solution F for protective layer were sequentially coated with a wire bar on a support for printing paper in which high quality paper was laminated with polyethylene, and dried at 50 ° C. to form diazo capsules. A coated paper was obtained. The coating amounts as solids were 0.8 g / m ² and 1.05 g / m ² , respectively.

[Fixing]: The entire surface was irradiated with light for 15 seconds using an ultraviolet lamp having an emission center wavelength of 365 nm and an output of 40 W. The density of the background portion of the obtained sample was measured with a Macbeth densitometer.

Next, the light resistance of the background part was tested. The comparative test was performed by continuously illuminating the fluorescent lamp at 32000 lux for 72 hours. The change in background density was measured with a Macbeth densitometer.

Examples 10 to 13 Instead of the diazonium salt compound used in Example 9, 2- (2-ethoxyethyl) oxy-4-bis [di (n-hexyl) aminocarbonylmethyl] aminobenzenediazonium was obtained. Hexafluorophosphate, 2-
(N-Butyl) oxy-4-bis [di (n-hexyl)
Aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (n-hexyl)
Oxy-4-bis [di (n-hexyl) aminocarbonylmethyl] aminobenzenediazonium hexafluorophosphate, 2- (2-ethylhexyl) oxy-
4-bis [di (isobutyl) aminocarbonylmethyl]
The same operation as in Example 9 was carried out except that a capsule liquid was obtained using aminobenzenediazonium hexafluorophosphate.

Comparative Examples 4 to 6 Instead of the diazonium salt compound used in Example 9, 2- (n-hexyl) oxy-4- [N- (1-methyl-2-phenoxy) ethyl, N-, respectively. n-hexyl] aminobenzenediazonium hexafluorophosphate, 2- (n-hexyl) oxy-4- <N- [1-methyl-2- (4-methylphenoxy)] ethyl, Nn
-Hexyl> aminobenzenediazonium hexafluorophosphate, 2- (n-hexyl) oxy-4-
<N- [1-Methyl-2- (4-methoxyphenoxy)] ethyl, Nn-hexyl> A procedure similar to that of Example 9 was carried out except that a capsule liquid was obtained using aminobenzenediazonium hexafluorophosphate. went.

Table 2 shows the results of measuring the coloring density (background density) of each diazo capsule-coated paper.

[0071]

[Table 2]

From the results shown in Tables 1 and 2, it is clear that the diazo heat-sensitive recording material using the diazonium salt compound of the present invention has a high light fastness of the image and the coloring of the background portion is small at the time of light irradiation after recording. is there.

Front page continuation (72) Inventor Mitsuyuki Tsurumi No. 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Fuji Photo Film Co., Ltd.

Claims (2)

[Claims] 1. A diazo thermosensitive recording material comprising a support and a recording layer containing a diazonium salt compound, a coupling component and an organic base, wherein the diazonium salt compound represented by the following general formula (I) is used. A diazo heat-sensitive recording material characterized in that General formula (I) In the formula, R ₁ , R ₂ , R ₃ , R ₄ and R ₅ represent a substituted or unsubstituted alkyl group, aralkyl group or aryl group. R ₂ and R ₃ or R ₄ and R ₅ may form a ring together with a nitrogen atom. X represents an acid anion. 2. The diazo heat-sensitive recording material according to claim 1, wherein the diazonium salt compound is contained in microcapsules.