JPS62201285A - Thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a thermal recording material having an excellent raw storage performance, a quick thermal response, a high thermal coloring performance and a low deterioration of the concentration of recording image after a long term storage by incorporating least one kind of fatty acid amide compound in the recording layer. CONSTITUTION:In a thermal recording material where a recording layer containing a diazo compound and a coupling component is applied onto a supporting member, at least one kind of fatty acid amide compound is contained in the recording layer. Preferably, any one of the diazo compound and the coupling component is contained in a microcapsule. Reactive material existing in the core or at the outside of the microcapsule is heated so as to permeate mainly through the wall of the microcapsule and react. In order to achieve an excellent raw storage performance, an improve thermal coloring performance and to lower the deterioration of the optical concentration of a recorded image due to long term storage after thermal recording, it is quite effective to incorporate a fatty acid amide compound as well as the diazo component and coupling component in the layer.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a heat-sensitive recording material, and particularly to a fixable diazo-based heat-sensitive recording material. More specifically, the present invention relates to a heat-sensitive recording material that has excellent storage stability before thermal recording, high color density during thermal recording (and can be photofixed after thermal recording).

"Prior Art" A leuco coloring type heat-sensitive recording material is usually used as a recording material used in a heat-sensitive recording method. However, this heat-sensitive recording material has the disadvantage that color develops in unexpected places due to harsh handling, heating, or adhesion of solvents after recording, which stains the recorded image. In recent years, research has been actively conducted on diazo color-forming heat-sensitive recording materials as heat-sensitive recording materials that do not have these drawbacks. For example, JP-A-57-/2
3ort, issue, Journal of the Institute of Image Electronics Engineers, L], 2ri0(/ri♂
2), etc., thermal recording is performed on a recording material using a diazo compound, a coupling component, and a basic component (substances that become basic when heated), and then light irradiation is performed. It decomposes unreacted diazo compounds and stops color development.

Indeed, according to this method, it is possible to stop color development (hereinafter referred to as fixing) in areas that do not require recording.

However, this recording material also undergoes gradual pre-coupling during storage, and undesirable coloring (fogging) may occur. To this end, it has been done to prevent contact between the components and prevent pre-coupling by making one of the coloring components exist in the form of discontinuous particles. It has disadvantages in that its stability (hereinafter referred to as raw storage stability) is not yet sufficient and its thermal coloring property is reduced.

As another measure, it is known to separate the diazo compound and the coupling component as separate layers in order to minimize contact between the components (for example, in the above-mentioned Japanese Patent Application Laid-Open No. 17-17-2
3016). Although this method improves raw storage stability, there is a significant drop in thermochromic properties (./e) It is not practical because it cannot respond to high-speed recording with a short width. As a method to satisfy both, either the coupling component or the basic substance is replaced with a non-contact waxy substance (JP-A-7-Hirohiro-7J1, JP-A-J-7-/μ2).
It is known to isolate it from other components by encapsulating it with a hydrophobic polymeric substance (Japanese Patent Publication No. 636) or a hydrophobic polymer substance (Japanese Patent Application Publication No. 2003-101002). However, these encapsulation methods involve dissolving wax or high-molecular substances in their solvents, and dissolving or dispersing color-forming ingredients in these solutions to form capsules. Its function is different from that of a capsule covered with a shell. For this purpose, when the coloring component is dissolved and formed, the coloring component does not become the core material of the capsule, but mixes uniformly with the capsule compound, and pre-coupling progresses during storage at the wall interface of the capsule, resulting in sufficient production. Preservability is not achieved. In addition, when a color-forming component is dispersed and formed, the color-forming reaction does not occur unless the capsule wall is thermally melted, resulting in a decrease in thermal color-forming properties. Furthermore, there is a manufacturing problem in that the solvent used to dissolve the wax or high molecular substance must be removed after the capsules are formed, and this method is not completely satisfactory.

Therefore, in order to solve these problems, a method of microencapsulating by containing at least one of the components involved in color reaction in the core material and forming a wall through polymerization around this core material has been developed to achieve excellent heat sensitivity. It has been found that recording material can be obtained.

``Problems to be Solved by the Invention'' However, even with heat-sensitive recording materials produced by this microencapsulation method, the optical density of the image-recorded area may apparently decrease due to long-term storage after heat recording. Improvement was desired.

``Object of the Invention'' Therefore, the first object of the present invention is to provide a thermosensitive material that has excellent raw storage stability, quick thermal response, high thermochromic property, and reduces the decrease in recorded image density during long-term storage after thermal recording. The goal is to provide recording materials.

A first object of the present invention is to provide a heat-sensitive recording material that can be fixed by photodecomposing unreacted diazo compounds after heat recording.

A third object of the present invention is to provide a heat-sensitive recording material with excellent manufacturing suitability.

"Means for Solving the Problems" As a result of intensive research, the present inventors have found that at least one fatty acid amide compound is added to a heat-sensitive recording material in which a recording layer containing a diazo compound and a coupling component is coated on a support. The problem has been solved by a heat-sensitive recording material that is characterized by being contained in the recording layer.

Note that either the diazo compound or the coupling component is preferably contained in microcapsules.

The microcapsules of the present invention are destroyed by heat or pressure, as is used in conventional recording materials, and the reactive substance contained in the core of the microcapsules is brought into contact with the reactive substance outside the microcapsules! - It does not cause a coloring reaction (it mainly permeates through the microcapsule wall and causes a reaction by heating the reactive substance present in the core and outside of the microcapsule).

As a result of intensive research into heat-sensitive recording materials using such microcapsules, the present inventors have found that they have excellent raw storage stability, good thermochromic properties, and improve the optical density of recorded images during long-term storage after heat recording. In order to eliminate the decrease, it has been found that it is extremely effective to include a fatty acid amide compound in the layer in addition to the diazo component and coupling component.

Preferred examples of fatty acid amide compounds in the present invention include compounds represented by the following general formula (I).

RCoNHz (I) in the above formula,
R represents an alkyl group which may have a substituent, preferably a group having the number of carbon atoms/r or less.

Examples of the substituent include an aryl group, a rogen atom, an A-acyl group, a cyano group, an alkoxy group, a thioalkoxy group, an acyloxy group, a thioaryloxy group, a cyano group,
Carbamoyl group, sulfamoyl group, carboxyl group,
It may have a hydroxyl group, an acylamino group, a dialkylamino group, etc.

In particular, the fatty acid amide represented by the following formula is advantageous in terms of its effectiveness and ease of availability.

krXRICONH2(]l) In the above formula, Ar represents an aryl group which may have a substituent.
1 is an alkyne group which may have a substituent, and X is -
5-1-〇- or -NR2-. R2 represents a hydrogen atom, an alkyl group or an acyl group.

Among these, fatty acid amides substituted with an aryloxy group at the α-position are particularly advantageous. Substituents for Ar include alkenyl groups, thioalkoxy groups, alkyl groups, aryl groups, alkoxy groups, aryloxy groups, halogen atoms, acyl groups, carbamoyl groups, sulfamoyl groups, hydroxy groups, substituted amino groups, carboxyl groups, and cyano groups. group, nitro group, or sulfo group.

Particularly preferred are a phenyl group, an alkyl group having -72 carbon atoms, an alkoxy group, an aryloxy group having 4 to 10 carbon atoms, a carbamoyl group, a hydroquine group, a chlorine atom, a fluorine atom, a hydroquinemethyl group, and the like.

Moreover, the above-mentioned alkyl group may have a linear, branched, or cyclic structure, and may further have a substituent. Examples of these substituents include aryl, halogen, cyano, hydroxy, acyloxy, aryloxy, acyl, and the like.

R is a methyl group, ethyl group, propyl group, isopropyl group, allyl group, dimethylbutyl group, t-amyl group, hexyl group, isoamyl group, cyclohexyl group, cyclohexylmethyl group, chlorobutyl group, methylcyclohexyl group, chloroethyl group , β-ace)-? diethyl group, 3-ketobutyl group, Hensyl group, α and β-phenethyl group, vinyl group, 5t-methyl group, impropenyl group, phenoxyethyl group, p-thiomethinephenol dimethyl group, o-thalolphenol dimethyl group, α-phenoxybutyl group, α-phenoxypropyl group, benzoylethyl group, tolyloxymethyl group, dimethylphenoxyethyl group, r-phenylpropyl group, β-phenoxyethyl group, β-tolyloxyethyl group, β-chlorophenoxyethyl group There are bases etc.

Among these, the melting point jt00cm is especially J'
Compounds of j'C to /♂o'C are preferred in the present invention. Furthermore, a compound having a solubility in water of 7 or less is preferable from the viewpoint of imparting resistance to the recording material.

Particularly preferred are fatty acid amides having a total number of carbon atoms of 10 or less.

Examples of specific compounds include the following.

α-Methylcinnamamide, methacrylamide, p-methoxyphenoxyacetamide, p-propylphenoxyacetamide, p-thiomethoxyphenoxyacetamide, p-methoxyphenoxyacetamide, p-
Methylphenoxyacetamide, p-benzyloxyphenoxyacetamide, m-methoxyphenoxy7acetamide, 2, μm dimethylphenoxyacetamide, 0
-chlorophenoquine acetamide, 0-ethylphenoxy/acetamide, 0-methoxyphenoxyacetamide, 0-methoxycarbonylphenoxyacetamide, p
-Hydroxythiophenoxyacetamide, p-ethylphenoxyacetamide, α-phenoxypropionamide, pivaloylamide, 2. Hiro-dichlorophenoxyacetamide, crotonamide, sorbic acid amide, sebacic acid diamide, dichlorohekiflucarbonamide,
λ-Methylcyclohequinyl acetamide, chlorothiophenoquine acetamide, α-phenoxybutyramide,
Examples include α-phenoquine-chloropropionamide, cumylphenoquine acetamide, α-hemonoacetylanilinoacetamide, benzoylacetamide, p-hydroxymethylphenoxyacetamide, crotonamide, and the like.

The diazo compound used in the present invention has the general formula ArN2”
X (In the formula, Ar represents an aromatic moiety, N2+ represents a diazonium group, and X- represents an acid anion.)
It is a diazonium salt represented by the formula, and is a compound that can develop a color by causing a coupling reaction with a coupling component, and can be decomposed by light.

Specifically, as the aromatic moiety, those having the following general formula are preferable.

n In the formula, Y represents a hydrogen atom, a substituted amino group, an alkoxy group, an aryloxy group, an arylthio group, an alkylthio group, or an acylamino group, and R represents a hydrogen atom, an alkyl group,
Alkoxy group, arylox7 group, arylamino group or -10gen (T.

Br, Cl, F). n represents l or 2.

Examples of the substituted amino group for Y include a monoalkylamino group, a dialkylamino group, an aryamino group, a morpholino group,
A piperidino group, a pyrrolidino group, etc. are preferred.

Specific examples of diazonium that forms salts include Kudiazo-l-dimethylaminobenzene, ψ-diazo-1-diethylaminobenzene, ψ-diazo-7-dipropylaminobenzene, Hiro-diazo-/-methylbenzylaminobenzene, ≠ -Diazo-7-dibenzylaminobenzene, ψ-diazo-7-ethylhydroxyethylaminobenzene, ≠-diazo-l-diethylamino-3-methoxybenzene, q-diazo-7-dimethylamino-2-methylbenzene, μm diazo -7-benzoylamino-2,
! -jethoxybenzene, Hiro-diazo-7-morpholinobenzene, q-diazo-7-morpholino~, 2. j-jethoxybenzene, Hiro-diazo-7-morpholino-2,
j-dibutoxy kunzene, Hiro-diazo-/-anilinobenzene, ≠-diazo/-1ruylmercapto λ,!
-diethoxy7benzene, goudiazo-/, ≠-methoxy inzoylamino λ,! -jethoxybenzene, μm
Examples include diazo-/-pyrrolidinocoetherbenzene.

Specific examples of acid anions include CnF2n+IC0O-
(n is an integer from 3 to 2), "mF2m+xsO3 (m is J
-f integer), (ceFz/+l5Oz)2cH(11
is an integer of /-/1), B (C6H5)4-, l
Examples include 3-H o3- 1/Hiro- (n is an integer of 3 to 3) B F 4 * PF 6- and the like.

In particular, as acid anions, those containing a perfluoroalkyl group or perfluoroalkenyl group, or PF6- are preferred because they cause less increase in chasm during raw storage.

As a specific example of a diazo compound (diazonium salt),
Examples include the following.

0C4Hc+ 0C2)Ls C4H9 1/71 The coupling component used in the present invention is one that forms a dye by coupling with a diazo compound (diazonium salt) in a basic atmosphere, and the R-form side,! : resorcin, phloroglucin, sodium 223-dihydroxy-7-naphthalene-6-sulfonate, /-hydroxyconaphthoic acid morpholinopropylamide, /l-dihydroxynaphthalene, λ, 3-dihydroxynaphthalene, λ.

3-dihydroxy-6-sulfanylnaphthalene, nohydroxy-3-naphthoic acid morpholinopropyl abad, euhydroxy-3-naphthoic acid anilide, euhydroxy-3-naphthoic acid-λ'-methylanilide, λ-
Hydroxy-3-naphthoic acid ethanolamide, no-hydroxy-3-naphthoic acid octylamide, λ-hydroxy-3-/I-naphthoic acid-N-dodecyl-oxyprobylamide,
λ-hydroxy-3-naphthoic acid tetradecylamide,
Acetanilide, acetoacetanilide, benzoylacetanilide, /-phenyl-3-methyl-! -pyrazolone, /-(2', μ'.

4/) Lichlorophenyl)-3-benzamide-! -pyrazolone, /-(2', q', 6'-trichlorophenyl)-3-anilino-j-bi5zolone, l
-Phenyl-3-phenylacetamide-j -H5
Son et al. Furthermore, by using two or more of these coupling components in combination, an image of any color tone can be obtained.

It is preferable to add a basic substance to the heat-sensitive recording material of the present invention in order to promote color development. Examples of the basic substance include basic substances that are poorly water-soluble or water-insoluble, and substances that generate alkali when heated. used.

Basic substances include inorganic and organic ammonium salts, organic amines, amides, urea and thiourea and their derivatives, thiazoles, virols, pIJ midines, pirazines, guanidines, indoles, imidazoles,
Examples include compounds containing imidacillins, triazoles, morpholines, lysines, amidines, formazines, pyridines, and the like. Specific examples of these include ammonium acetate, tricyclohexylamine, tribenzylamine, octadecylbenzylamine, stearylamine, allyl urea, thiourea, methyl thiourea, allyl thiourea, ethynethiourea, λ-benzylimidazole, and Hirofue. Nilimitasol, λ-
Phenyl-Hiro-methyl-imidazole, λ-undecyl-imidacillin, co, 4A, j-trifuryl-co-imidazoline, /.

Coke phenyl-4L, sol, cophenylucoimigzolin%/1j, J
−) Riphenylguanidine, tritolylguanidine, /
12-dicyclohexylguanidine, /,2.3-)dicyclohexylguanidine, guanidine trichloroacetate, N,N'-dibenzylpiperazine, ≠,μ'-dithiomorpholine, diphenylbenzamidine, ditolylbenzamidine, There are co-aminobenzothiazole and λ-penzoylhydrazinopenzothiazole. Two or more of these basic substances can also be used in combination.

In the present invention, a reactive substance contained in the core substance of a microcapsule is dissolved or dispersed in a water-insoluble organic solvent, and after emulsification, a microcapsule wall is formed around it by polymerization. The boiling point is preferably .

n-type +clti, IJ acid esters, phthalic acid esters, other carzene acid esters, fatty acid amides, alkylated hypohenyls, alkylated terphenyls, chlorinated paraffins, alkylated naphthalenes, diarylethanes, etc. are used. Specific examples include tricresyl phosphate, trioctyl phosphate, octyldiphenyl phosphate, tricyclohexyl phosphate, dibutyl phthalate, dioctyl phthalate, dilauryl phthalate, dicyclohexyl phthalate, phthyl oleate, diethylene glycol dibenzoate, and sepamate. Dioctyl heptaphosphate, digtyl sebacate,
Dioctyl adipate, trioctyl trimellitate,
Acetyl triethyl citrate, octyl maninate, dibutyl maleate, isopropylbiphenyl, inamyl biphenyl, chlorinated roughin, diisopropylnaphthalene, /, /'-ditolylethane, co. Hirojitanyariaminophenol, N-dibutyl-λ-butoxy! -tertiary octylaniline and the like.

Among these, ester solvents such as dibutyl phthalate, tricresyl phosphate, diethyl phthalate, and digtyl maninate are particularly preferred.

The microcapsules of the present invention are made by emulsifying a core material containing a reactive substance and then forming a wall of a polymeric material around the oil droplets. The actant forming the polymeric material is added to the interior of the oil droplet and/or to the exterior of the oil droplet. Specific examples of polymeric substances include polyurethane, polyurea,
Polyamide, polyester, polycarbonate, urea
formaldehyde resin, melamine resin, polystyrene,
-2 +2- Styrene methacrylate copolymer, styrene-acrylate copolymer, gelatin, polyvinylpyrrolidone, polyvinyl alcohol and the like.

Two or more types of polymeric substances can also be used in combination.

Preferred polymeric materials are polyurethane, polyurea, polyamide, polyester, polycarbonate, and more preferred are polyurethane and polyurea.

The microcapsule wall of the present invention is particularly effective when using a microencapsulation method by polymerizing a glue actant from inside an oil droplet. That is, it is possible to obtain capsules, which are desirable as a recording material and have a uniform particle size and excellent storage stability, within a short period of time.

This method and specific examples of compounds are described in U.S. Pat.
．． 72t, No. 1017, 3, 7FA, i! l
It is stated in the specification of No.

For example, when polyurethane is used as a capsule wall material, a polyvalent isocyanate and a second substance (such as a polyol) that reacts with it to form the capsule wall are mixed into an oily liquid to be encapsulated, emulsified and dispersed in water, and then heated to a temperature. By rising, a polymer formation reaction occurs at the oil droplet interface, forming a microcapsule wall. At this time, an auxiliary bath agent with a low boiling point and strong dissolving power can be used in the oily liquid.

In this case, the polyisocyanate to be used, the polyol to be reacted with it, and the polyamine are disclosed in U.S. Pat.
26g issue, special public Akihiro? −≠03 Hiro 7, same μter, 2≠
/jri issue, Tokukai Akibi♂-10/ri7, Dohiro♂-♂≠o
rt, and they can also be used.

Furthermore, a tin salt or the like can also be used in combination to promote the urethanization reaction.

In particular, it is preferable to use a polyvalent incyanate as the first wall-forming substance and a polyol as the second wall-forming substance because of good shelf life. Furthermore, by combining the two, it is also possible to arbitrarily change the thermal permeability of the reactive substance.

Examples of the polyvalent isocyanate that is the first wall film-forming substance include m-phenylene diisocyanate, p-phenylene diisocyanate, λ,6-dolylene diisocyanate, 2. μ-tolylene diisocyanate, naphthalene-71μm diisocyanate, diphenylmethane, μ′-diisocyanate, 3,3′-dimethquine≠
, ≠′-biphenyl diisocyanate, 3.3′-dimethyldiphenylmethane-hiro, l-diisocyanate,
Xylylene-/, ≠-diisocyanate, μ, μ′-diphenylpropane diisocyanate, trimethylene diisocyanate, hemolytic methylene diisocyanate, propylene-/2.2-diisocyanate, butylene-/,
Diisocyanates such as 2-diisocyanate, cyclohexylene-/, 2-diisocyanate, cyclohexylene-/, Hiro-diisocyanate, ≠, 4L/, l
Triisocyanates such as A//-triphenylmethane triisocyanate, toluene-J, 44.4-triisocyanate, 44. l-dimethyldiphenylmethane-λ,2',! , j'-tetrasocyanene-+2
j- Tetrisonanate, adduct of hexamethylene diisocyanate and trimethylolpropane, λ,
There are inanate prepolymers such as adducts of ≠-tolylene diisocyanate and trimethylolpropane, adducts of quinlylene diisocyanate and trimethylolpropane, and adducts of trinonediisocyanate and hesantriol.

Examples of the polyol as the second wall-forming substance include aliphatic and aromatic polyhydric alcohols, hydrocarbon polyesters,
There are things like hydroxypolyalone ether. Preferred polyols include polyhydroquine compounds having the following group (I), (II), (1), or (IV) in the molecular structure between two hydroxyl groups and having a molecular weight of less than zoooo.

(I) Any aliphatic hydrocarbon group having 2 to 2 carbon atoms (II)
-C-0-Ar -0-C--2- ■ (fV) 0-Ar -C-Ar -0-Here, Ar in (II), (III), and (IV) is substituted or absent. It represents a substituted aromatic moiety, and the aliphatic hydrocarbon group (I) has -C1H2n- as a basic skeleton, and the hydrogen group may be substituted with another element.

In terms of media, examples of (I) include ethylene glycol, 113-propanediol, /, IA-butanediol, /, j-<butanediol, /
, &-hexanediol, /, 7-hebutansinol,
/,? -octanediol, propylene glycol,
2. J-dihydroxybutane, /, 2-dihydroxybutane, 1I3-dihydroxybutane, λlλ-dimethyl-/, 3-1'ropanediol, 22μm bentanediol, λ, j-hexanediol, 3-methyl-
7,j-bentanediol, 72 μm cyclohexane dimetatool, dihydroxycyclohexane, diethylene glycol, /, 2. Examples include t-trihydroxyhexane, phenylethylene glycol, /, /, /-trimethylolpropane, hexanetriol, pentaerythritol, and glycerin.

Examples of (Il) include condensation products of aromatic polyhydric alcohols and alkylene oxides such as /, 4L-di(2-hydroethyl)benzene, and resorcinol dihydroxyethyl ether.

Examples of (III) include p-xylylene glycol,
m-quinrylene glycol, α, α'-dihydroxy-p-diisopropylbenzene, etc. are used.

Examples of (IV) include g,l-dihydroxy-diphenylmethane, λ-(1)+1)'-dihydroxydiphenylmethyl)benzyl alcohol, addition of ethylene oxide to bisphenol A, and addition of propylene oxide to bisphenol. Things can be given. The polyol is preferably used in a proportion of hydroxyl groups of 0.02 to λ mol per mol of incyanate groups.

When making microcapsules, water-soluble polymers can be used, and the water-soluble polymers may be any of water-bathable anionic polymers, nonionic polymers, and amphoteric polymers.

Both natural and synthetic anionic polymers can be used, such as -COO-1-S Oa
Examples include those having a group or the like. Examples of anionic natural polymers used as media include gum arabic and alginic acid, while semi-synthetic products include caloxymethyl cellulose, phthalated gelatin, sulfated starch, sulfated cellulose, and lignin sulfonic acid.

Synthetic products include maleic anhydride-based (including hydrolyzed) copolymers, acrylic acid-based (including methacrylic acid-based) polymers and copolymers, vinylbenzenesulfonic acid-based polymers and copolymers, Examples include carboxy-modified polyvinyl alcohol.

Examples of nonionic polymers include polyvinyl alcohol, hydroxyethyl cellulose, and methyl cellulose.

Examples of amphoteric compounds include gelatin.

These water-soluble polymers are used as a 0.0/~10 wt% aqueous solution. The particle size of the microcapsules is adjusted to 20μ or less. Generally, if the particle size exceeds 20 μm, the print quality tends to be poor.

In particular, when heating with a thermal head is performed from the coated layer side, the thickness is preferably tμ or less in order to avoid pressure fog.

Of the diazo compound that is the main component used in the present invention, the coupling component, and the basic substance used if necessary, any seven of them may be used as the core material of the microcapsule, or two or three of them may be used. Seeds can be used. When two types are contained in the core material of microcapsules, they may be in the same microcapsule or in separate microcapsules. Further, when three types are contained in the core material of a microcapsule, it is not possible to simultaneously contain the three types in the same microcapsule, but there are various combinations. Other ingredients not contained in the core material of the microcapsules are used in the heat-sensitive layer outside the microcapsules.

The fatty acid amide compound of the present invention may be present in the core of the microcapsule or outside.

When making microcapsules, they can be made from an emulsion containing 0.1wt1 or more of the component to be microencapsulated.

Diazo compound used in the present invention, coupling component,
And whether the basic substance used as necessary is contained inside the microcapsule or contained in the heat-sensitive layer outside the microcapsule, the coupling component is 0.0% based on the diazo compound/part by weight. The basic substance is preferably used in an amount of 0.1 to 20 parts by weight. Also, the diazo compound is 0.0! -j, 097m2
It is preferable to apply it.

When the diazo compound, coupling component, and basic substance used in the present invention are not microencapsulated, they are preferably used after being dispersed in solid form with a water-soluble polymer using a sand mill or the like. Preferred water-soluble polymers include water-soluble polymers that can be used when making microcapsules.

At this time, the concentration of water-soluble polymer is 2 to 30 wt%,
A diazo compound, a coupling component, and a basic substance are each added to this water-soluble polymer solution in amounts of -μOwt.

The dispersed particle size is preferably 10 microns or less.

In the heat-sensitive recording material of the present invention, various compounds such as ether, phenol, sulfonamide, carboxylic acid amide, ester, and ketone may be used in combination with the aryl alkanol compound for the purpose of improving thermal color development. For example, cobenzyloxynaphthalene, /-p-hyphenyloxy-cophenylethane,
λ-benzoyloxynaphthalene, 2-phenoxyacetyloxynaphthalene, λ-p-thalolobenzyloxynaphthalene/-hydroxycophenoquincari-nylna75'lene, /, Hiro-bisphenoxybutane, /,
2-bis-m-tolyloxyethane l-phenoxy-2
-p-ethylphenoxyethane, /, cordiphenoxyethane, l-phenoquine-col-chlorophenoxyethane, bis(phenoxyethyl)oxalate, l-phenoxy-λ-p-methquinephenoxyethane, β-chloroethoxynaphthane IJ
Luo beef kushietane bis(phenoxyethyl) carzenate, biphenyl-β-methoxyethyl ether, p-biphenyl-β-cyclohexyloxyethyl ether,
β-Anoethoxynafume, β-Chloroethoxyn
p-biphenyl, λ-phenoxyphenyloxycarbonylphenol, λ-p-biphenyloxycarbonylphenol, β-naphthyloxycarbonylphenol, bis(2-p-methoxyphenoxyethyl) ether, bis(2-p-ethoxyphenoxy) Ethers such as ethyl) ether, bis(-2-p-methoxyphenoxyethoxy)methyl ether, 2-bisgumethoxydithiophenoxyethane, or butylphenol, p-
t-octylphenol, p-α-cumylphenol,
p-i--<methylphenol, X, S-dimethylphenol, co.

p, s-t') methylphenol, 3-methyl-Hiro-isopropylphenol, p-benzylphenol, 0-
cyclofluphenol, p-(diphenylmethyl)
Phenol, p-(α,α-Schifznylethyl)phenol, o-phenylphenol, butyl p-hydroxybenzoate, chloropyr p-hydroxybenzoate, butyl p-hydroxybenzoate, benzyl p-hydrobenzoate, p-methquinphenol, p-butquinphenol, p-hebutyloxyphenol, p-benzyloxyphenol, 3-hydroxyphthalic acid, dimethylvanillin, 2,! -diethylphenol, /,/-bis(≠-hydroxyphenyl)dodecane, /,/-bis(≠-hydrobydiphenyl)-2-ethyl-3 ≠-hexane, /,/-bis(Hiro-hydroquinphenyl) −
Comethyl-bentane, 2-bis(≠-hydroxyphenyl)-hebutane, vanillin, λ-t-i Chiruhiro-methoxyphenol-dimethoxyphenol, 2,2'-dihydroxy-≠-methoxybenzophenone, β - Phenols such as resorcinic acid phenoxyethyl ester, orceric acid α-methylbenzyl ester, hydroquine methyl cinnamate, or ethylbenzenesulfonamide, toluenesulfonamide, methoxybenzenesulfonamide, ethyltoluenesulfonamide, chloroethoxybenzenesulfonamide , (iso)propylbenzenesulfonamide, ethoxytoluenesulfonamide, t-amylbenzenesulfonamide, diethylbenzenesulfonamide, allylbenzenesulfonamide, β-ethoxyethquinbenzenesulfonamide, cyclohexylbenzenesulfonamide, or , benzamide,
m-methquinpenzamide, methylbenzamide, ethylbenzamide, inpropylbenzamide, butylbenzamide, t-amylbenzamide, shedquipenzamide, dimethylbenzamide, nicotinamide, picolinamide, naphthamide, phenylbenzamide ,
Chlorobenzamide, 0-chloropenzamide, methoxychlorobenzamide, methquintoluamide, ethoxybenzamide, butylbenzamide, dimethylnaphtho, trimethylbenzamide, dimethylchlorobenzamide, dimethoxychlorobenzamide, dimethoxybenzamide , shedchlorbenzamide, diethylaminobenzamide, phthalamide, methoxycarbonylbenzamide, methquintoluamide, benzylbenzamide, chloroethylbenzamide, chloroethquinbenzamide, annobenzamide, benzyloxy7penzamide, etc. Examples include amide compounds. Two or more of these can also be used in combination.

These compounds can be used by making microcapsules together with the core material of the microcapsules, or by being added to the coating solution of the heat-sensitive recording material and existing outside the microcapsules. is preferred. In either case, the amount used is 0.0/-10 parts by weight based on the coupling component/part by weight, preferably O1/-j parts by weight, but it can be selected as appropriate to adjust the coloring density to the desired level. Bye.

A free radical generator (a compound that generates free radicals when irradiated with light) used in photopolymerizable compositions is added to the heat-sensitive recording material of the present invention for the purpose of reducing yellowing of the background after photofixing. be able to. Examples of free radical generators include aromatic ketones (e.g., benzophenone, Hiroshi, μ′-bis(dimethylamino)benzophenone, !, l-bis(diethylamino)benzophenone, ≠-methoxyμ′(dimethylamino)benzophenone, Hiroshi, 4L'-dimethoxybenzophenone, ≠-dimethylaminobenzophenone, ≠-
Methoxy! , 3'-dimethinebenzophenone, /-hydroxy 7cyclohexylphenyl ketone, Hiro-dimethylaminoacetophenone, comethyl-/-(Hiro-(methylthio)phenylcou 2-morpholino-propanone-/
-acetophenone, benzyl), cyclic aromatic ketones (
For example, fluorenone, anthrone, xanthone, thioxanthone, λ-chlorothioyasanthone, 21≠-dimethylthiogysanthone, 21 μm diethylthioxanthone, acridone, N-ethyl acridone, benzanthrone), quinones (allegedly benzoquinone, ' p3*
'h'J Methyl-6-promobenzoquinone, λ
, 6-di-n-decylbenzoquinone, /, 1A-naphthoquinone, λ-isopropoquine/, ≠-naphthoquinone,
/, 2-naphthoquinone, anthraquinone, λ-chloroanthraquinone, λ-methylanthraquinone, 2-t
ert-butylanthraquinone, phenanthraquinone)
, benzoin, benzoin ethers (e.g. benzoin methyl ether, benzoin ethyl ether, 2, -
i! -dimethoxy-2-phenylacetophenone, α-
methylolbenzoin methyl ether), aromatic polycyclic hydrocarbons (e.g. naphthalene, a3 r-anthra7ane, phenanthrene, hyrene), aso compounds (
For example, azobisisobutyronitrile, α-7:, /”
-/-cyclohexanecarbonitrile, azobisvaleronitrile), organic disulfides (e.g., thiuram disulfide), acyloxime esters (e.g.,
benzyl-(0-ethoxycarbonyl)-α-monoquine).

The amount to be added is based on the diazonium compound/part by weight.
Preferably, the free radical generator is used in an amount of 0.0X to j parts by weight. More preferably 0. /-/ parts by weight.

By encapsulating the free radical generator together with the diazonium salt as the core material of the microcapsule, the above-mentioned yellowing of the background after photofixing can be reduced.

In the heat-sensitive recording material of the present invention, a polymerizable compound having an ethylenically unsaturated bond (hereinafter referred to as a vinyl monomer) can be used for the purpose of reducing yellowing of the background after photofixing. A vinyl monomer is a compound having at least 7 ethylenically unsaturated bonds (vinyl group, vinylidene group, etc.) in its chemical structure, and is a compound that has at least 7 ethylenically unsaturated bonds (vinyl group, vinylidene group, etc.), and is a compound that contains monomers, prepolymers, i.e., dimers, trimers, and other It has chemical forms such as oligomers, mixtures thereof, and copolymers thereof. Examples thereof include unsaturated carboxylic acids and salts thereof, esters of unsaturated carmenic acids and aliphatic polyhydric alcohol compounds, amides of unsaturated carboxylic acids and aliphatic polyhydric amine compounds, and the like.

The vinyl monomer is O, X based on the diazo compound/part by weight.
It is used in a proportion of ~-20 parts by weight. Preferably 7-10
It is a proportion of parts by weight.

The vinyl monomer is used by being contained in the core material of the microcapsule together with the diazo compound, but at this time, the solvent for the core material (
Seven parts or all of the organic solvent used as a dispersion medium (or dispersion medium) can be replaced with vinyl monomer, but it is not necessary to add enough to harden the core material.

When the heat-sensitive recording material of the present invention contains a diazo compound as a core material, by incorporating a coupling reaction deactivator outside the microcapsules, the diazo compound present in the aqueous phase and the diazo compound in the incomplete capsules can be removed. (i.e., the diazo compound that is not completely locked by the capsule wall) and the coupling reaction quencher react, and the diazo compound reacts with the coupling reaction (coloring reaction).
ability to be lost and fogging can be prevented.

The coupling reaction deactivator may be any substance that reduces the coloring of the solution in which the diazo compound is dissolved (i.e., the diazo compound is dissolved in water or an organic solvent, and then the diazo compound is dissolved in water or an organic solvent; Selection can be made by adding other compounds and observing the change in color of the diazo compound.

Specifically, -hydroquinone, sodium bisulfite,
Examples include potassium nitrite, hypophosphorous acid, stannous chloride, and formalin. In addition to this, )1゜5unders
Author: “The Aromatic Diaz.

-Compounds and Their Te
chnicalApplicationsJ (Lon
It is also possible to select from those described in 1996, published by Don)/Tagta, page 101-306.

The coupling reaction quenching agent is preferably one that has little coloring itself and has few side effects. More preferably, it is a water-soluble substance.

The coupling reaction deactivator is used to the extent that it does not inhibit the thermal coloring reaction of the diazo compound.
The deactivator is used in an amount of 0.01 to 2 moles per mole. More preferably, it is used in a range of 0.02 mol to 1 mol.

The coupling reaction quencher of the present invention is a liquid in which microcapsules containing a diazo compound are dispersed after being dissolved in a solvent;
Alternatively, it can be used by adding a coupling agent or a basic substance to a dispersed liquid or a mixture thereof. Preferably, the quencher is used in the form of an aqueous solution.

The heat-sensitive recording material of the present invention contains silica, barium sulfate, titanium oxide, aluminum hydroxide, zinc oxide,
Pigments such as Cal/Rum carbonate, fine powders such as -μ-monostyrene beads, urea-melamine resin, etc. can be used.

Similarly, metal soaps can also be used to prevent sticking. The usage amount of these is Oo
, 2~797m2.

Furthermore, a heat-melting substance can be used in the heat-sensitive recording material of the present invention in order to increase the heat-recording density.

As a heat-melting substance, it is solid at room temperature, but has a melting point that melts when heated by a thermal head! It is a substance of O~/j 00C, and it is a substance that dissolves a diazo compound, a coupling component, or a basic substance. The thermofusible substance is 0. /~1
Dispersed in 0μ particles, solid content 0.2-7 g/y
used in the amount x. Specific examples of heat-melting substances include arylamides, he-substituted fatty acid amides, chtonic compounds, urea compounds, and esters.

The heat-sensitive recording material of the present invention can be coated with a suitable binder.

Binders include polyvinyl alcohol, methylcellulose, carbodimethylcellulose, hydrodipropylcellulose, gum arabic, gelatin, polyvinylpyrrolidone, casein, styrene-butadiene latex, acrylonitrile-butadiene latex, polyacrylamide, polyvinyl acetate, polyacrylic acid. Various emulsions of esters and ethylene-vinyl acetate copolymers can be used. The amount used is solid content O, S~jg
/m.

In the present invention, in addition to the above materials, citric acid is used as an acid stabilizer.
Tartaric acid, oxalic acid, boric acid, phosphoric acid, birophosphoric acid can be added.

The heat-sensitive recording material of the present invention is produced by preparing a coating liquid containing the main components of a diazo compound and a coupling component, as well as a basic substance and other additives, and coating it on a support such as paper or a synthetic resin film with a bar. After coating and drying, the solid content λ,! ~
, 2!17/m2 heat-sensitive layer is provided. Another method is to add the main components of the coupling component, basic substances, and other additives as the core material of microcapsules, or to disperse them as solids, or to dissolve them as an aqueous solution and then mix them to form a coating solution. prepared, coated on a support, dried to form a precoat layer with a solid content of λ~lOg/rIL2, and further added thereon with the main component diazo compound and other additives as the core material of the microcapsules, or Alternatively, apply a coating solution made by dispersing solids or dissolving them as an aqueous solution and mixing them, and dry to reduce the solid content.
It is also possible to use a laminated type with a coating layer of g/rrL2. The laminated type heat-sensitive recording material may have a reverse order of lamination, and the coating method may be sequential coating or simultaneous coating of the laminated layers. This laminated heat-sensitive recording material exhibits particularly excellent performance in long-term storage.

Also special wishes on the support! It is also possible to apply the heat-sensitive layer after providing the intermediate layer described in Patent No. 77447.

The paper used for the support is a neutral paper sized with a neutral sizing agent such as an alkyl ketene dimer and heat-extracted by Kazuhiro Yo-ichi P) 14 ~ 2 g
The use of the product described in No. 1) is advantageous in terms of storage stability over time.

In addition, in order to prevent the coating liquid from penetrating into the paper and to improve the contact between the recording heat head and the heat-sensitive recording layer, there is
/; Paper described in No. f7 and having a Bekk smoothness of 0 seconds or more is advantageous.

Tokukai Akihiko again? -13t≠Paper with an optical surface roughness of rμ or less and a thickness of ≠Q~7jμ as described in JP-A-Shoj
lr-density O6ri g/C1rL as described in Nori Ori No. 1
A paper with an optical contact rate of less than or equal to or greater than Tachi, JP-A-Sho! ♂
Canadian Standard Reactor Water Level (JIS
JP-A-Sho, a paper made from pulp that has been beaten to a degree of 0OCC or higher using Pr12/) to prevent coating liquid from seeping in! Zaichi 6! JP-A-Sho, which improves color density and resolution by using the glossy side of base paper made by a Yangyu machine as the coating surface, as described in Otori No. 5. q written in the tar 3j rs issue
6- Papers whose coatability has been improved by subjecting the base paper to corona radiation treatment can also be used in the present invention and give good results.

In addition to these, any support commonly used in the field of heat-sensitive recording paper can be used as the support of the present invention.

The heat-sensitive recording material of the present invention can be used as printer paper for facsimiles and electronic computers that require high-speed recording, and can be fixed by exposing it to light after heating and decomposing unreacted diazo compounds. . In addition, it can also be used as a thermal phenomenon type copy paper.

"Example" Examples are shown below, but the present invention is not limited thereto. Note that "parts" indicating the amount added represent "parts by weight."

"Examples of the invention" Example 1 The following diazo compound 3. ≠J part and (3:/) adduct 1 of xylylene diisonanate and trimethylolpropane
1 part was added to a mixed solvent of 2≠ parts of tricresyl phosphate and 5 parts of ethyl acetate and dissolved.

The solution of this diazo compound is mixed with polyvinyl alcohol.
Part 2 is water! is mixed with an aqueous solution in which 1.2 parts of
(1) Emulsification and dispersion was carried out at 0C to obtain an emulsion with an average particle diameter of λ and 3μ. 100 parts of water was added to the obtained emulsion and heated to a temperature of 100 ml while stirring, and after one hour, a capsule liquid containing a diazo compound in the core substance was obtained.

(Diazo compound) C4H9 Next, in addition to 10 parts of nohydroquine-3-naphthoic acid anilide and 100 parts of triphenylguanidine iof#trts polyvinyl alcohol aqueous solution, about 2
A dispersion of the coupling component and triphenylguanidine with an average particle size of 3 μm was obtained by Koji time dispersion.

Further, 20 parts of phenogine acetamide was added to ≠100 parts of a polyvinyl alcohol aqueous solution and 100 parts of water and dispersed in an India shaker for 2 hours to obtain a dispersion of phenoxyacetamide having an average particle size of 3 μm.

Capsule liquid of diazo compound obtained as above 5
Coupling component in 0 part, 2≠part of triphenylguanidine dispersion, 21r of phenoxyacetamide dispersion
A coating solution was prepared by adding 50% of the total amount. Spread this coating solution on smooth high-quality paper (
3097m2) using a coating bar to give a dry weight of 10fj/m2, and dried at 230C for 30 minutes to obtain a heat-sensitive material.

Example 2 A thermosensitive recording material was obtained in the same manner as in Example 1, except that p-methylphenoxyacetamide was used instead of phenoxyacetamide.

Example 3 A heat-sensitive recording material was obtained in the same manner as in Example 1, except that p-methoxyphenoxyacetamide was used instead of fenoquine acetamide.

-μter Example 4 A thermosensitive recording material was obtained in the same manner as in Example 1 except that di-0-chlorophenoxyacetamide was used in place of the phenoxyacetamide in Example 1.

Comparative Example Except for not containing phenoxyacetamide of Example 1,
A thermosensitive recording material was obtained in the same manner as in Example 1.

(Test method) The obtained heat-sensitive recording material was thermally recorded using a GI mode thermal printer (Hifax 700; manufactured by Hitachi, Ltd.), and then the entire surface was exposed using Ricoh Sunono-Dry 100 (manufactured by Ricoh ■). It took root. The blue density of the obtained visual image was measured using a Macbeth reflection densitometer. Also, the same (the yellow density of the background area was measured).

The results are shown in Table 2. On the other hand, when thermal recording was performed again on the fixed portions, no image was recorded on any of them, and it was confirmed that they were fixed.

Next, in order to examine the storage stability, we examined the jO− background density (fog) of the heat-sensitive recording material and the aO0C1 of the heat-sensitive recording material.
The film was stored in a dark place for 2 hours under conditions of relative humidity and 0% RH, and after a forced deterioration test, fog was measured using a Macbeth reflection densitometer to observe changes in fog.

Next, in order to investigate the decrease in optical density of the colored part due to long-term storage after thermal recording, the recorded image of the thermal recording material was
The image was stored in a dark place under OC conditions for 4 hours, and the degree of decrease in density of the recorded image was evaluated after performing a forced deterioration test.

The results are shown in Table 2.

These results show that the compound of the present invention is significantly effective in improving image density.

Claims (1)

[Claims] 1. A heat-sensitive recording material comprising a recording layer containing a diazo compound and a coupling component coated on a support, the recording layer containing at least one fatty acid amide compound.