JP3213120B2 - Diazo thermal recording material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a recording material utilizing the photosensitivity of a diazo compound (diazonium salt). More specifically, the present invention relates to a diazo thermosensitive recording material for forming a color image comprising a diazo compound, a coupling component and a base.

[0002]

2. Description of the Related Art There are generally three types of recording materials utilizing the photosensitivity of diazo compounds. One is a type known as a wet development type, in which a photosensitive layer having a diazo compound and a coupling component as main components is provided on a support, and this material is overlapped with a document and exposed to an alkaline solution. To be developed. The second type is known as a dry development type, in which development is performed with ammonia gas, unlike the wet development type. The third type is known as a heat-developable type, which contains an ammonia gas generator such as urea, which can generate ammonia gas by heating in the photosensitive layer, and a type such as trichloroacetic acid in the photosensitive layer. Examples include a type containing an alkali salt of an acid which loses its properties as an acid upon mild heating, and a type utilizing activation of a diazo compound and a coupling component by heating and melting using a higher fatty acid amide as a coloring aid.

The wet type requires a replenishment and disposal of the developer due to the use of a developing solution, has a maintenance problem such as a large apparatus, and can be added immediately because the copy is wet immediately. There are some problems such as not being able to withstand long-term storage of copied images. In addition to the fact that the dry type requires replenishment of the developer as well as the wet type, gas absorption equipment is required so that the generated ammonia gas does not leak to the outside, and thus the equipment becomes larger, It has problems such as smell of ammonia immediately after copying. On the other hand, the heat development type has a maintenance advantage because it does not require a developer unlike the wet type or the dry type, but the conventionally known types have a high development temperature of 150 ° C. to 200 ° C. In addition, if the temperature is not controlled to about ± 10 ° C., the development becomes insufficient or the color tone changes, so that there has been a problem that the apparatus cost is increased. Also, a diazo compound used for such high-temperature development needs to have high heat resistance, but such a compound is often disadvantageous for forming a high concentration. Low temperature development (90
(130 ° C. to 130 ° C.), but there is a disadvantage that the shelf life of the material itself is reduced. As described above, the heat development type is not yet occupying the mainstream of the diazo recording system, although the maintenance advantage is sufficiently expected as compared with the wet or dry type.
Now, in order to obtain a desired color density by heating a material provided with a layer containing a diazo compound and a coupling component on a support, each component is instantaneously melted, diffused and reacted by heating to form a coloring dye. However, it is preferable to make the system basic during this reaction because it has the effect of accelerating the reaction. Therefore, in order to prepare a light and heat sensitive recording material having a recording speed at which heating at low temperature does not cause a practical obstacle, it is essential to include a basic substance in the coating layer.

On the other hand, it is also an essential requirement for a diazo thermosensitive recording material that the background portion is prevented from being colored or the color density is reduced during storage before copying as much as possible.

[0005] With such a good shelf life,
Although some attempts have been made to produce a diazo thermosensitive recording material having a high recording speed, the present situation is that it has not yet reached practical use.

[0006] If a material is designed to sufficiently develop color and obtain a high density even when the heating temperature is low, a color reaction may naturally occur even during storage at room temperature before copying. It appears as a phenomenon in which the ground which must be white becomes colored. In particular, in the case of a recording material of a red coloring type, since the visibility is high, slight coloring of the background (fog)
But there was the problem of being noticeable. The present inventors have conducted intensive studies to solve this seemingly incompatible problem, and as a result, in a recording material provided with a thermally developable photosensitive layer containing a diazo compound, a coupling component and a basic substance on a support. Including the diazo compound in the microcapsules, and further studying from the viewpoint of searching for a basic substance, making microcapsules, etc.
Successful suppression of background coloring during pre-storage
-54251). Further, as a result of intensive studies for the purpose of enhancing the storage stability and oil solubility of the diazo compound, it was found that 4-substituted amino-2-alkoxybenzenediazonium salts exhibited excellent performance (Japanese Patent Application Laid-Open No. 4-59288, JP-A-4-59288, Kaihei 4-197778). However, the recording material containing the 4-substituted amino-2-alkoxybenzenediazonium salt did not reach a satisfactory level of raw preservability (ground coloring during pre-copying preservation). For the purpose of solving this drawback, the present inventors have conducted intensive studies, and as a result, have found that a diazo compound having a specific substituent exhibits excellent performance, and reached the present invention.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a diazo thermosensitive recording material which is excellent in preservability (raw preservability) before recording.

[0008]

The above objects of the present invention are:
A diazo thermosensitive recording material comprising a support and a recording layer containing a diazo compound, a coupling component, and an organic base, wherein the diazo compound contains the general formula (I) . Achieved. General formula (I)

[0009]

Embedded image

Wherein R ₁ is -C (W ₁ ) (W ₂ ) -C
(W ₃₎ (W ₄₎ represents a -O-W _5.

[0011]

[0012]

[0013]

[0014]

R ₂ and R ₃ may be the same or different and represent an alkyl group, an aralkyl group, or an aryl group;
These may further have a substituent.

R ₁ and R ₂ may form a ring via the substituent A.

X represents an acid anion.

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

Y ₆ represents a hydrogen atom, an alkyl group, an aralkyl group, or an aryl group, which may further have a substituent.

[0025]

[0026]

[0027]

In the general formula (I), R ₁ is preferably
_{CH (W 1) CH 2 O} -W 5, -CH (W 1) -CH
(W ₃₎ -O-W ₅ are preferred, and most preferably, -C
H (W ₁ ) CH ₂ O-W ₅ is preferred.

However, W ₁ represents an alkyl group, which may further have a substituent.

W ₂ represents a hydrogen atom. W ₃ and W ₄ are
Represents a hydrogen atom, an alkyl group, an aralkyl group, or an aryl group, and W ₅ represents an alkyl group, an aralkyl group, or an aryl group.
And these may further have a substituent.

In the general formula (I), a group represented by W ₁
Is preferably an alkyl group having 1 to 18 carbon atoms,
_{As the} group represented by ₂ , R ₃ , W ₃ , W ₄ and W ₅ , an alkyl group having 1 to 18 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and an aryl group having 6 to 20 carbon atoms are preferable.
Further, it may have a substituent.

In the general formula (I), R_Two , R_Three ,W
₁ , W _Three  , W_Four And W_Five Has a substituent,
Examples of the group include an alkyl group, an aryl group, a hydroxy group,
Alkyloxy group, aryloxy group, alkylthio group,
Arylthio group, acyl group, alkoxycarbonyl group,
Acyloxy, carbamoyl, acylamino, c
And a halogen atom and a cyano group.

In the general formula (I), R_Two , R_Three ,W
₁ , W _Three  , W_Four And W_Five Has a substituent,
Examples of the group include an alkyl group having 1 to 18 carbon atoms and 6 to 2 carbon atoms.
0 aryl group, hydroxy group, C 1-18 alkyl
Killoxy group, aryl having 6 to 20 carbon atomsOxyKi, charcoal
Alkylthio group having 1 to 18 primes, ant having 6 to 20 carbon atoms
Thiol group, alkylcarbonyl group having 2 to 25 carbon atoms,
Arylcarbonyl group having 7 to 35 carbon atoms, 2 to 2 carbon atoms
5 alkoxycarbonyl groups, acyl having 2 to 20 carbon atoms
Oxy group, carbamoyl group having 2 to 37 carbon atoms, 2 carbon atoms
To 35 acylamino groups, halogen atoms and cyano groups are preferred.
Good.

[0034]

[0035]

[0036]

[0037]

[0038]

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

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

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 A diazonium salt can also be stabilized by forming a complex compound using sulfonic acid, zinc chloride, cadmium chloride, tin chloride or the like.

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

When the microcapsules are used, they are dissolved in an appropriate solvent (for example, tricresyl phosphate or the like) before use, so that they have appropriate solubility in these solvents and low water solubility. preferable. Specifically, it is preferable to have a solubility of 5% or more in the solvent and a solubility of 1% or less in water.

The diazo compound according to the present invention is preferably used in the heat-sensitive recording layer in the range of 0.02 to 3 g / m ² , and is preferably used in the range of 0.1 to ² g / m ² from the viewpoint of color density. Preferably.

Hereinafter, specific examples of the diazo compound according to the present invention will be shown, but the present invention is not limited thereto.

[0046]

Embedded image

[0047]

Embedded image

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

And the like.

The diazo compounds according to the present invention may be used alone or in combination of two or more.

The microcapsules used in the present invention are:
After emulsifying and dispersing a solution in which a diazonium salt and the same or different compound that reacts with each other to form a polymer substance in a non-aqueous solvent having a boiling point of 40 to 95 ° C. at normal pressure are dispersed in a hydrophilic protective colloid solution, The temperature of the system is raised while the pressure in the reaction vessel is reduced, and the wall-forming substance is transferred to the oil droplet surface while distilling off the solvent. It is preferable from the viewpoint of obtaining a good shelf life that the microcapsules are substantially free of a solvent produced by the formation of

The non-aqueous solvent for dissolving the diazonium salt used in the present invention is at least one compound selected from halogenated hydrocarbons, carboxylic esters, phosphoric esters, ketones and ethers. Preferably, there is.

The same or different compounds forming the walls of the microcapsules used in the present invention and reacting with each other to produce a high molecular substance are preferably polyureas and urethanes, and aromatic or aliphatic isocyanate compounds as the corresponding monomers. Selected. The microcapsule containing the diazo compound of the present invention can be obtained by polymerizing the corresponding monomer, and the amount of the monomer used is 0.3 μm to 12 μm in average particle diameter of the microcapsule and 0.01 μm in wall thickness. It is determined to be 0.3 μm . Further, the diazo compound is preferably applied in an amount of 0.05 to 5.0 g / m ² .

The coupling component according to the present invention includes:
A color is formed by a coupling reaction with the above diazo compound in a basic atmosphere, and can be selected according to a desired hue. Specific examples of these include, for example, resorcin, phloroglysin, sodium 2,3-hydroxynaphthalene-6-sulfonate, 2-hydroxy-3
-Sodium naphthalene sulfonate, 2-hydroxy-
3-naphthalenesulfonic acid anilide, 2-hydroxy-
3-naphthalenesulfonic acid morpholinoamide, 2-hydroxy-3-naphthalenesulfonic acid morpholinopyropyramide, 2-hydroxy-3-naphthalenesulfonic acid-
2-ethyl-hexyloxypropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethyl-hexylamide, 1-hydroxy-8-acetylaminonaphthalene-3,6-disulfonate sodium, 1-hydroxy-8- Acetylaminonaphthalene-3,6-disulfonic acid dianilide, 1-hydroxy-2-naphthoic acid morpholinopropylamide, 1,5-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,3-dihydroxy-6-naphthalenesulfonic acid amide , 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 octylamide, 2-hydroxy- 3-naphthoic acid octylamide, 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 tetradecylamide, 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-hydroxyethylamide, acetanilide, 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-phenylacetamido-5-pyrazolone, 1-methyl-3
-Phenyl-2,4,6,-(1H, 3H, 5H) -pyrimidinetrione, 1-octadecyloxypropyl-
3-phenyl-2,4,6,-(1H, 3H, 5H)-
Pyrimidinetrione, 1-phenyl-3- (2,5-dioctyloxyphenyl) -2,4,6,-(1H, 3
H, 5H) -pyrimidinetrione, 5,5-dimethyl-
Cyclohexane-1,3-dione, 5- (2-tetradecyloxyphenyl) -cyclohexane-1,3-dione, N- (2-ethyl-hexyloxypropyl) -3
-Cyano-4-ethyl-6-hydroxy-2-pyridone, N- (dodecyloxypropyl) -3-acetyl-
4-methyl-6-hydroxy-2-pyridone and the like 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 thermal development and promoting the coupling reaction. These organic bases can 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.

[0062] 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
Piperazines such as -methylpiperazino) -2-hydroxy] propyloxydibenzene, N- [3- (β-naphthoxy) -2-hydroxy] propylmorpholine,
Morpholines such as 1,4-bis [(3-morpholino-2-hydroxy) propyloxy] benzene, 1,3-bis [(3-morpholino-2-hydroxy) propyloxy] benzene, N- (3-phenoxy) Concretely preferred are piperidines such as (-2-hydroxypropyl) piperidine and N-dodecylpiperidine, and guanidines such as triphenylguanidine, tricyclohexylguanidine, dicyclohexylphenylguanidine and the like.

In the present invention, the coupling component is preferably used in an amount of 0.1 to 30 parts by weight, and the basic substance is preferably used in an amount of 0.1 to 30 parts by weight, based on 1 part by weight of the diazo compound.

In the present invention, a coloring aid may be added in addition to the organic base for the purpose of accelerating the coloring reaction.

The color-forming aid of the present invention includes:
For example, a phenol derivative, a naphthol derivative, an alkoxy-substituted benzene, an alkoxy-substituted naphthalene, a hydroxy compound, an amide compound, or a sulfonamide compound can be added to the photosensitive layer so that thermal development is performed quickly and completely with low energy. . These compounds are
It is considered that the melting point of the coupling component or the basic substance is reduced, or the heat permeability of the microcapsule wall is improved, so that a high color density can be obtained.

The coloring aid of the present invention also includes a heat-fusible 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 dissolves a diazo compound, a coupling component, or a basic substance. Specific examples of these compounds include carboxylic amides, N-substituted carboxylic amides, ketone compounds, urea compounds, esters and the like.

The coupling component used in the present invention comprises:
It can be used as a solid dispersion together with a water-soluble polymer by a sand mill or the like together with a basic substance, other color-forming auxiliaries, and the like, but is particularly excellent for use as an emulsion with a suitable emulsifying aid. Preferred water-soluble polymers include water-soluble polymers used when preparing microcapsules (for example, JP-A-59-19).
0886). In this case, the coupling component, the basic substance, and the coloring aid are added to the water-soluble polymer solution in an amount of 5 to 40% by weight. Preferably, the size of the dispersed or emulsified particles is less than 10 microns.

To the recording material of the present invention, a free radical generator (a compound which generates free radicals 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, acyl oxime esters, and the like. The amount to be added is 0.01 to 1.0 part by weight of the free radical generator per 1 part by weight of the diazo compound.
5 parts by weight are preferred.

Similarly, for the purpose of reducing yellow coloring, a polymerizable compound having an ethylenically unsaturated bond (hereinafter, referred to as a 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 a monomer or prepolymer. Examples thereof 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 diazo compound.

The free radical generator and the vinyl monomer can be used in a microcapsule together with a diazo compound.

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.

The recording material of the present invention is prepared by preparing a microcapsule containing a diazo compound, a coupling component, and a coating solution containing an organic base and other additives, and forming the coating solution on a support such as paper or a synthetic resin film. Is coated and dried by a coating method such as bar coating, blade coating, air knife coating, gravure coating, roll coating coating, spray coating, dip coating, curtain coating and the like to obtain a solid content of 2.5 to 30 g / m.
^Two photosensitive layers are provided.

In the recording material of the present invention, microcapsules, coupling components, bases and the like may be contained in the same layer as described in the above method, or may be of a laminated type in which they are contained in another layer. Can also be taken. Further, after providing an intermediate layer described in Japanese Patent Application No. 59-177669 on a support, a photosensitive layer can be coated.

As the support of the present invention, any paper support used for ordinary pressure-sensitive paper, thermal paper, dry or wet diazo copy paper, etc., and neutral support such as alkyl ketene dimer can be used. Neutral paper having a pH of 5 to 9 sized with a sizing agent (described in Japanese Patent Application No. 55-14281), satisfying the relationship between the Stechig sizing degree and the metric basis weight described in JP-A-57-116687, and Paper having a Beck smoothness of 90 seconds or more, an optical surface roughness described in JP-A-58-136492 of 8 μ or less, and a thickness of 30 to
Paper having a density of 0.9 g / cm ³ or less and an optical contact ratio of 15% or more described in JP-A-58-69091; and a Canadian standard freeness described in JP-A-58-69097. Paper made from pulp beaten to 400 cc or more according to JIS P8121) to prevent the infiltration of the coating solution, and the glossy surface of the base paper made by the Yankee machine described in JP-A-58-65695 was used as the coated surface, and the color density and Paper having improved resolution, paper obtained by subjecting a base paper described in JP-A-59-35985 to corona discharge treatment to improve coating suitability, and the like can also be used.

The synthetic resin film used as a support in the present invention can be arbitrarily selected from known materials having no dimensional stability even when heated during the development process and having 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, and polyolefin films such as polyethylene. Can be used. The thickness of the support is 20 to 200 μm.

When forming an image on the recording material of the present invention,
The following method can be used. One is a method in which a latent image is formed by exposing a document using an original, and then fixing is performed by irradiating light to portions other than the image forming portion.
This is a method in which a colored image is obtained by heat of a hot pen, a thermal head, or the like, and then fixing is performed by irradiating light to portions other than the image portion. Either method can be preferably used. As a light source for exposure, various fluorescent lamps, xenon lamps, mercury lamps, and the like are used, and it is efficient that the emission spectrum almost coincides with the absorption spectrum of the diazo compound used in the recording material, except for the image forming portion. Light fixing is preferable. In the step of heating and developing the material, a heating pen, a thermal head, an infrared ray, a high frequency wave, a heat block, a heat roller, or the like can be used as a heating means.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0078]

【Example】

Example 1 [Preparation of capsule liquid A of the present invention]: To 19 parts of ethyl acetate, 2.8 parts of the specific compound example (3) of the present invention and 10 parts of tricresyl phosphate were added and mixed uniformly. Next, 7.6 parts of Takenate D-110N (manufactured by Takeda Pharmaceutical Co., Ltd.) was added to this mixed solution as a wall material, and the mixture was mixed uniformly to obtain Liquid I. Next, an 8% by weight aqueous solution of phthalated gelatin 46.1 was prepared.
Parts, 17.5 parts of water and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate at 40 ° C. and 10,000 r.p. p. m for 10 minutes. After 20 parts of water was added to the obtained emulsion to homogenize it, an encapsulation reaction was performed at 40 ° C. for 3 hours with stirring to obtain a capsule liquid A. The particle size of the capsule was 0.35 μm.

[Preparation of coupler / base emulsion B]: 5- (2-tetradecyloxyphenyl) was added to 8 parts of ethyl acetate.
-Cyclohexane-1,3-dione 4 parts, triphenylguanidine 2 parts, tricresyl phosphate 0.64
Parts, maleic acid diethyl ester 0.32 parts
Solution I was obtained. Next, 32 parts of a 15% by weight aqueous solution of lime-processed gelatin, 5 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate, and 30 parts of water were uniformly mixed at 40 ° C. II
The solution was added, and the mixture was added at 40 ° C. and 10,000 using a homogenizer.
r. p. m. For 10 minutes. After stirring the obtained emulsion at 40 ° C. for 2 hours to remove ethyl acetate, the weight of the evaporated ethyl acetate and water was supplemented with water to obtain a coupler / 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 9 parts were uniformly mixed at 40 ° C., 8.3 parts of coupler / base emulsion B was added and uniformly mixed to obtain a heat-sensitive recording layer coating solution C. [Preparation of protective layer coating liquid D]: A protective layer coating liquid D was obtained by uniformly mixing 32 parts of a 10% aqueous solution of polyvinyl alcohol (degree of polymerization: 1700, saponification degree: 88%) and 36 parts of water.

[Coating]: On a photographic paper support obtained by laminating polyethylene on a high-quality paper, a coating solution C for the heat-sensitive recording layer and a coating solution D for the protective layer were applied in this order by a wire bar and then applied at 50 ° C.
To obtain the desired diazo thermosensitive recording material. The coating amounts as solids were 6.4 g / m ² and 1.05, respectively.
g / m ² .

[Coloring and Fixing Test]: Using a thermal head (KST type) manufactured by Kyocera Corporation, the applied power and pulse width to the thermal head were adjusted so that the recording energy per unit area was 0 to 40 mJ / mm ^2. After performing thermal printing on the determined diazo thermosensitive recording layer and obtaining an image, the entire surface was irradiated 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 color-developed portion and the background portion of the obtained sample was measured with a Macbeth densitometer.

[ Comparative test of raw preservability]: The test of raw preservability was performed by comparing a diazo thermosensitive recording sheet stored at room temperature with
The comparison was made based on the difference between the color density and the background density of a diazo thermosensitive recording sheet forcibly stored for 72 hours under the condition of% RH. The change in coloring density was measured with a Macbeth reflection densitometer.

Example 2 A recording material was prepared by performing the same operation as in Example 1 except that a capsule liquid was obtained using the compound (8) instead of the compound (3) used in Example 1. Was formed. The density of the color-developed portion and the background was measured using a Macbeth densitometer.

[0085]

Example 3 Instead of 5- (2-tetradecyloxyphenyl) -cyclohexane-1,3-dione used in Example 1, 1
-Octadecyloxypropyl-3-phenyl-2,
A recording material was prepared and an image was formed by performing the same operation as in Example 1 except that a coupler / base emulsion liquid was obtained using 4,6,-(1H, 3H, 5H) -pyrimidinetrione. The density of the color-developed portion and the background was measured using a Macbeth densitometer.

[0087]

Comparative Example 1 Instead of the compound (3) used in Example 1, 4-N, N
-Dihexylamino-2-hexyloxybenzenediazonium hexafluorophosphate was carried out in the same manner as in Example 1, except that an image was formed. It was 1.21 when the density of the coloring part was measured with the Macbeth densitometer.

Comparative Example 2 Instead of the compound (3) used in Example 1, 4- [N-
(4-methoxyphenoxyethyl), N-hexyl] amino-2-hexyloxybenzenediazonium hexafluorophosphate was used to obtain an image by performing the same operation as in Example 1 except that a capsule solution was obtained. The density of the colored portion was measured with a Macbeth densitometer.

Comparative Example 3 Instead of the compound (3) used in Example 1, 4- [N-
(4-methoxyphenoxypropyl), N-hexyl]
An image was formed in the same manner as in Example 1 except that a capsule solution was obtained using amino-2-hexyloxybenzenediazonium hexafluorophosphate. The density of the colored portion was measured with a Macbeth densitometer.

Table 1 shows the results of the measurement of the coloring density and the background density.

[0092]

[Table 1]

Example 4 [Preparation of Capsule Solution A of the Present Invention]: To 19 parts of ethyl acetate, add 2.8 parts of the specific compound example (1) of the present invention and 10 parts of tricresyl phosphate and uniformly mix. did. Next, 7.6 parts of Takenate D-110N (manufactured by Takeda Pharmaceutical Co., Ltd.) was added to this mixed solution as a wall material, and the mixture was mixed uniformly to obtain Liquid I. Next, an 8% by weight aqueous solution of phthalated gelatin 46.1 was prepared.
Parts, 17.5 parts of water and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate at 40 ° C. and 10,000 r.p. p. m for 10 minutes. After 20 parts of water was added to the obtained emulsion to homogenize it, an encapsulation reaction was performed at 40 ° C. for 3 hours with stirring to obtain a capsule liquid A. 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
9 parts were uniformly mixed at 40 ° C. to obtain a coating solution E. [Preparation of protective layer coating liquid D]: A protective layer coating liquid D was obtained by uniformly mixing 32 parts of a 10% aqueous solution of polyvinyl alcohol (degree of polymerization: 1700, saponification degree: 88%) and 36 parts of water.

[Coating]: Coating liquid E and protective layer coating liquid D were sequentially coated and dried at 50 ° C. on a photographic paper support obtained by laminating polyethylene on a high-quality paper with a wire bar. 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 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 of the obtained sample was measured with a Macbeth densitometer.

[ Comparative Test of Raw Storage Property]: The test of raw storage property is based on the difference in background density between diazo capsule coated paper stored at room temperature and diazo capsule coated paper forcibly stored at 60 ° C. and 30% RH for 72 hours. Was compared. The change in coloring density was measured with a Macbeth reflection densitometer.

Example 5 The same operation as in Example 1 was carried out except that a capsule liquid was obtained by using Compound (2) in place of Compound (1) used in Example 4 , to obtain a background of diazo-encapsulated paper. The comparison was made based on the difference in concentration.

Example 6 The same operation as in Example 1 was carried out except that a capsule liquid was obtained using compound (3) in place of compound (1) used in example 4 , to obtain a background of diazo-encapsulated paper. The comparison was made based on the difference in concentration.

Example 7 The same operation as in Example 1 was carried out, except that the compound (4) was used in place of the compound (1) used in Example 4 , to obtain a capsule solution. The comparison was made based on the difference in concentration.

[0102] instead of the compound used in Example 8 Example 4 (1) was treated in the same manner as other Examples 4 to obtain a capsule solution by using a compound (5), the background of the diazo capsule coated paper The comparison was made based on the difference in concentration.

Comparative Example 4 Instead of the compound (3) used in Example 4 , 4-N, N
-Dihexylamino-2-hexyloxybenzenediazonium hexafluorophosphate was used, except that a capsule solution was obtained, and the same operation as in Example 4 was performed.

Comparative Example 5 Instead of the compound (3) used in Example 4 , 4- [N-
(4-Methoxyphenoxyethyl), N-hexyl] amino-2-hexyloxybenzenediazonium hexafluorophosphate, except that a capsule solution was obtained using the same procedure as in Example 4 to obtain a background density of the diazo capsule coated paper. Were compared.

Comparative Example 6 Instead of the compound (3) used in Example 4 , 4- [N-
(4-methoxyphenoxypropyl), N-hexyl]
The same operation as in Example 4 was performed except that an capsule solution was obtained using amino-2-hexyloxybenzenediazonium hexafluorophosphate, and the difference was compared based on the difference in the background density of the diazo capsule coated paper.

Table 2 shows the results of the background density measurement.

[0106]

[Table 2]

From these results, it is clear that the diazo thermosensitive recording sheet using the diazo compound of the present invention shows excellent raw preservability with little decrease in color density and high background whiteness.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Kamikawa 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Inside Fujisha Shin Film Co., Ltd. (56) References JP-A-4-59288 (JP, A) JP-A-4- 197782 (JP, A) JP-A-64-80588 (JP, A) JP-A-4-247447 (JP, A) JP-A-7-125446 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/28-5/34 G03C 1/52

Claims (2)

(57) [Claims] 1. A diazo thermosensitive recording material comprising a support having thereon a recording layer containing a diazo compound, a coupling component and an organic base, wherein the diazo compound has the general formula (I)
Diazo heat-sensitive recording material which comprises a. General formula (I) In the formula, R ₁ represents —C (W ₁ ) (W ₂ ) −C (W ₃ ) (W ₄
) Represents a -O-W _5. Here, W ₁ represents an alkyl group.
W ₂ represents a hydrogen atom. , W ₃ and W ₄ are hydrogen atoms,
Represents an alkyl group, an aralkyl group, or an aryl group. W ₅ is,
Represents an alkyl group, an aralkyl group, or an aryl group. R ₂ and R ₃ represent an alkyl group, an aralkyl group, and an aryl group. X represents an acid anion. 2. The thermosensitive diazo recording material according to claim 1, wherein the diazo compound is contained in a microcapsule.