JPH04164682A - Recording material - Google Patents

Abstract

PURPOSE:To obtain a recording material imparting a developed color image enhanced in stability by using a specific compound as an electron donating leuco dye. CONSTITUTION:In a recording material utilizing the color development due to the contact of an electron donating leuco dye and an electron acceptive compound, as the electron donating leuco dye represented by general formula (I) is used. The recording material can be also constituted by using the leuco dye in combination with various compounds such as a triphenylmethanephthalide type compound, a fluorane type compound, a fluorene type compound and the like. At this time, it is desired to pref. use 30% or more of the leuco dye from the aspect of the improvement in characteristics. The electron donating leuco dye and the electron acceptive compound are ground and dispersed in a dispersing medium so as to reach a particle size of 10mu or less before use. The wt. ratio of the electron donating leuco dye and the electron acceptive compound is pref. set to (1:10)-(1:1) and, at this time, it is pref. to together use a hot-melt substance.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a recording material, and in particular to a recording material with improved stability of a colored image (Prior Art) Recording using an electron-donating colorless dye and an electron-accepting compound The materials are already well known as pressure sensitive paper, thermal paper, photosensitive pressure sensitive paper, electrically conductive thermal recording paper, thermal transfer paper, and the like. For example, British Patent No. 2140449, U.S. Patent No. 4480052, U.S. Pat.
For details, see No. 60-123557.

As a recording material, in recent years (1) color density and color sensitivity (2)
) Research is being carried out to improve properties such as before use and the fastness of colored images.

Among these, in blue-light recording materials, especially (2)
There is a strong demand for

For example, the blue coloring agent 3.3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalate (i.e., crystal violet lactone) develops quickly and exhibits a deep blue color, and the light fastness of the colored image changes. The plasticizer properties are extremely poor.

The present inventors have discovered that certain compounds are effective in improving these properties.

(Object of the Invention) Therefore, an object of the present invention is to provide a recording material using a material that has good stability of a colored image and satisfies other requirements.

(Structure of the Invention) An object of the present invention is to provide a recording material that utilizes color development through contact between an electron-donating colorless dye and an electron-accepting compound, in which the electron-donating colorless dye is represented by the following general formula (I). This was achieved using a recording material characterized by the use of a compound that

In the above formula, Ar+ and Art represent a heterocyclic group, R, ~R.

is a hydrogen atom, an alkyl group, a phenyl group, and R4 is CRi
RI R7, PO(OR-)-1-N R* COR
1o (Rs to R+ represents a hydrogen atom or a -valent group; however, at least one of R5 to R7 represents an electron-withdrawing group).

In addition, an alkyl group, an aryl group, and a heterocyclic group further include an alkyl group, an alkoxy group, an aryl group, an aryloxy group,
It may have a substituent such as a halogen atom, nitro group, cyano group, substituted carbamoyl group, substituted sulfamoyl group, substituted amino group, substituted oxycarponyl group, substituted oxysulfonyl group, alkylthio group, or arylsulfonyl group.

Each of the heterocyclic groups Ar+ and Art preferably has 30 or less carbon atoms, particularly preferably 20 or less carbon atoms.

Among the above-mentioned heterocycles, from the viewpoint of synthetic handling, substituted indole, carbazole, pyrrole, indolenine,
Preferred are quinoline, thiophene, benzothiazole, benzoxazole, and benzimidazole residues, and particularly preferred are indole and carbazole residues in which the nitrogen atom is substituted with an alkyl group or an aryl group.

More specifically, A r I, A r 2 or the following general formula (
A heterocyclic group represented by (2) is preferable.

In the above formula, among the substituents represented by R11, hydrogen atoms, alkyl groups having 1 to 18 carbon atoms, and 6 to 1 carbon atoms
The aryl group of 8 is preferred.

R1+ is a hydrogen atom, methyl group, ethyl group, n-propyl group, 1so-propyl group, n-butyl group, 1so
-butyl group, n-amyl group, 1so-amyl group, n-hexyl group, n-hebutyl group, n-octyl group, 2-ethylhexyl group, n-dodecyl group, n-oftadenol group,
β-methoxyethyl group, β-ethoxyethyl group, γ-methoxypropyl group, γ-ethoxypropyl group, β-phenoxyethyl group, β-tolyloxyethyl group, β-chlorophenoxyethyl group, β-methoxyphenoxyethyl group , β-ethylphenoxyethyl group, β-phenoxyprobyl group, β-cyanoethyl group, β-chloroethyl group,
β-hydroxyethyl group, cyclopentyl group, cyclohexyl group, phenyl group, tolyl group, chlorophenyl group,
Examples include methoxyphenyl group, benzyl group, phenethyl group, methylbenzyl group, chlorobenzyl group, and methoxybenzyl group.

Among the substituents represented by R+t, a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an aryl group having 6 to 12 carbon atoms are preferred.

Examples of R3 include a hydrogen atom, a methyl group, an ethyl group, a phenyl group, and a tolyl group.

Among the substituents represented by Rt2, hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, alkoxy groups, and 2 carbon atoms
12 alkoxycarbonyl groups, acyloxy groups,
Aryl group having 6 to 12 carbon atoms, aryloxy group, aryloxycarbonyl group having 7 to 12 carbon atoms, hydroxy group, chlorine atom, bromine atom, fluorine atom, nitro group, cyan group, amino group, number of carbon atoms Preferred are mono- or dialkylamino groups having 1 to 12 carbon atoms, mono- or diarylamino groups having 6 to 12 carbon atoms, and acylamino groups having 1 to 12 carbon atoms.

Rt2 is a hydrogen atom, methyl group, ethyl group, propyl group, butyl group, octyl group, phenyl group, tolyl group,
benzyl group, phenethyl group, methoxy group, ethoxy group,
Propoxy group, butoxy group, octyloxy group, benzyloxy group, phenoxyethoxy group, phenoxy group, chlorine atom, bromine atom, fluorine atom, nitro group, cyano group, dimethylamino group, diethylamino group, dipropylamino group, acetylamino group group, acetyloxy group, and methoxycarbonyl group.

Among the substituents represented by R1-R2, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, and a phenyl group are preferred. R
l'=R2 is a hydrogen atom, a methyl group, an ethyl group,
Examples include propyl group, butyl group, hexyl group, octyl group, methoxypropyl group, phenoxyethyl group, cyclopentyl group, cyclohexyl group, hensyl group, phenethyl group, and phenyl group, with hydrogen atom being particularly preferred.

Among the substituents represented by R4, CRs Rt Rt , PO(OR-)2, -NRI having 30 or less carbon atoms, especially 20 or less
COR,. (R5-R1° represents a hydrogen atom or a -valent group; however, at least one of R6-R7 represents an electron-withdrawing group) is preferred.

R6-R7 are hydrogen atoms, alkyl groups, aryl groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, halogen atoms, cyano groups, nitro groups, 5Ot
R1,, COR+ *, NR1, R17 [R34, R
16 is a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group,
an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a hydroxy group, N Rl* R+ s, and R1 and - R11 are a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, 5O2R*.

, C0RI, (R20, R1+ represent a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group)], and further R-1
R7 may be linked to each other and contain a heteroatom 4
~Represents a 12-membered ring structure.

R1 represents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group, and R1 represents a 4- to 12-membered ring structure which may be connected to each other and may contain a heteroatom.

R1 is a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group,
Hydroxy group, COR2! , R1゜, Rtt, a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, and further R,,
R. represents a 4- to 12-membered ring structure which is connected to each other and may contain a hetero atom.

Furthermore, in terms of handling of synthesis, R4 is CRs Rt
R7, -NRs C0RI.

is preferred.

In particular, from the viewpoint of the stability of the leuco color former when used in a recording material, CRs Rs Rt is preferred.

As R4, diethylphosphonyl group, dibutylphosphonyl group, diphenylphosphonyl group, di(4-tolyl)phosphonyl group, di(4-chlorophenyl)phosphonyl group,
Di(4-methoxyphenyl)phosphonyl group, di(4-nitrophenyl)phosphonyl group, di(4-cyanophenyl)phosphonyl group, di(naphthalen-]-yl)phosphonyl group, di(naphthalen-2-yl)phosphonyl group Base, Ji (
2,4-dichlorophenyl)phosphonyl group, cy(4-chloro-3-methylphenyl)phosphonyl group, succinylimide group, phthalimide group, acetylamino group, benzoylamino group, 2-methylbenzoylamino group, 4-methylbenzoylamino group group, 4-chlorobenzoylamino group, 1,1-diacetylmethyl group,! , 1-dicyanomethyl group, l-acetyl-1-benzoylmethyl group, 1.
1-dimethoxycarbonylmethyl group, 1.1-jethoxycarbonylmethyl group, 1.1-dipropoxycarbonylmethyl group, 1.1-diphenyloxycarbonylmethyl group, 1.1-di-n-butoxycarbonylmethyl group,
1. I-di-1so-butoxycarbonylmethyl group, 1
．． 1-t-butine sulfonylmethyl group, 1,1-
Cypentyloxycarbonylmethyl group, 1,1-cyhexyloxycarbonylmethyl group, l,1-cyhenzyloxycarbonylmethyl group, 1,1-cyoctyloxysulfonylmethyl group, l-phenoxycarnanyl-1- Methoxycarbonylmethyl group, 1-phenoxysulfonyl-1-ethoxycarbonylmethyl group, l-phenoxycarbonyl-1-butoxycarbonylmethyl group, 1-acetyl-1-methoxycarbonylmethyl group, l-acetyl-1-ethoxycarbonyl Methyl group, l-acetyl-1
-1so-proboxycarbonylmethyl group, 1-acetyl-]-butoxycarbonylmethyl group, 1-acetyl-
1-hexyloxycarbonylmethyl group, 1-acetyl-1-octyloquinolsulfonylmethyl group, l-acetyl-1-benzyloxycarbonylmethyl group, l-acetyl-1-phenoxycarbonylmethyl group, 1-propionyl-1 -methoxycarbonylmethyl group, 1-acetyl-1-ethoxycarbonylethyl group, 1,1-diacetylethyl group, l-pivaloyl-I-methoxycarbonylmethyl group, l-cyano-1-ethoxycarbonylmethyl group, l- Benzoyl-1-ethoxycarbonylmethyl group, l-acetyl-1-morpholinocarbonylmethyl group, 1-methoxycarbonyl-1-ethoxycarbonylmethyl group, l.

■-Diphenylsulfonylmethyl group, 1-tolylsulfonyl-1-benzoylmethyl group, 1.1-di(trifluoromethylcarbonyl)methyl group, 1.1-dipivaloylmethyl group, l-furoyl-1-)ly Fluoromethylcarbonylmethyl group, l-thienylcarbonyl-1-
trifluoromethylcarbonylmethyl group, 1. ]-dicarbamoylmethyl group,! -acetyl-1-phenylcarbamoylmethyl group, 1,1-dibenzoylmethyl group, 1
, l-dimethoxycarbonylethyl group, 1.1-jethoxycarbonylethyl group, 1.1-diphenyloxycarbonylethyl group, 1.1-di-n-butoxycarbonylethyl group, l,1-di-t-butoxy carbonylethyl group, 1. l-benzyloxylponylethyl group,
1.1-dimethoxycarbonyl-n-propyl group, l,
I-dimethoxycarbonyl-n-butyl group, α,α-dimethoxycarbonylbenzyl group, 1.1-dimethoxycarbonyl-1-methoxymethyl group, 1.1-jethoxycarbonyl-n-propyl group, 1. 1-jethoxycarbonyl-1so-propyl group, 1,1-jethoxycarbonyl-n-butyl group, j,l-jethoxycarbonyl-1so-butyl group, 1,l-jethoxycarbonyl-tert-butyl group, α, α-jethoxycarbonylpencyl group, β, β-jethoxycarbonylphenethyl group, 1゜1~jethoxycarbonyl-1-allylmethyl group, ], 1-jethoxysulfonyl-1-acetaminomethyl group, ], ] -jethoxycarbonyl-1-chloromethyl group, 1.1-jethoxycarbonyl-1-cyclopentylmethyl group, 1.1-jethoxycarbonyl-1
-phthalimidomethyl group, (1), 1-jethoxycarbonyl-2-ethoxycarbonylethyl group, 1,1,1. −
h-ethoxycarponylmethyl group, benzoylmethyl group, 4-chlorobenzoylmethyl group, 4-nitrobenzoylmethyl group, ]-chloro-1-acetylmethyl group, I-
Examples include chloro-1-methoxycarbonylmethyl group, l-bromo-1-benzoylmethyl group, nitromethyl group, and 1-nitroethyl group.

Next, specific examples of the color former of the present invention will be shown, but the present invention is not limited thereto.

In addition, these colorless dyes are already well-known triphenylmethane phthalide compounds, fluoran compounds,
Assemble recording materials in combination with various compounds such as phenothiazine compounds, indolylphthalide compounds, leucoauramine compounds, rhodamine lactam compounds, triphenylmethane compounds, triazene compounds, spiropyran compounds, and fluorene compounds. You can also do that.

In this case, it is preferable to use the above-mentioned colorless dye in an amount of 30% or more from the viewpoint of improving properties.

Regarding these, for example, specific examples of phthalides are U.S. Reissue Patent No. 23,024 and U.S. Patent No. 3°491.111.
No. 3,491,112, No. 3,491,116, and No. 3,509.174, and specific examples of fluorans are U.S. Pat.
No. 7, No. 3゜641.011, No. 3,462,828
No. 3,681,390, No. 3,920,510, No. 3,959,571, specific examples of spiropyrans are U.S. Pat. No. 3,971,808, and pyridine and pyrazine compounds are U.S. Pat. Patent No. 3,775.424, No. 3
, No. 853.869, No. 4.246,318, and specific examples of fluorene compounds are described in Japanese Patent Application No. 61-240989.

Electron-accepting compounds that impart color upon contact with colorless dyes include common compounds such as phenol derivatives, salicylic acid derivatives, benzoic acid derivatives, metal salts of aromatic carboxylic acids, acid clay, bentonite, noholac resins, and metal-treated novolak resins. , metal complexes, etc. are used, and these may be used in combination. Examples of these are the Tokko Kokko 1973. -9
No. 309, JP 45-14039, JP 52-1
No. 40483, JP-A-48-51510, JP-A-57
-210886, JP 58-87089, JP 59-11286, JP 60-176795, JP 61-95988, U.S. Patent No. 3,767.449
No. 4,219,219, No. 4,269,893, No. 4,374゜671, No. 4,687,869, etc. Particularly preferred are combinations with salicylic acid derivatives, phenol derivatives, metal complexes, acid clay, and bentonite. When these are applied to recording materials, they are used in the form of fine dispersions or fine droplets, or in the form of films.

Furthermore, in this case, various additives well known in the field of recording materials and polymer resins, such as pigments, waxes, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, and fluorescent agents, are added. Additives such as dyes and surfactants are used.

For use with pressure sensitive paper, U.S. Patent 2,505.470
No. 2,505,471, No. 2,505.489, No. 2,548,366, No. 2,712,507,
No. 2,730,456, No. 2,730,45.7,
It takes various forms as described in prior patents such as No. 3,103,404, No. 3,418,250, and No. 4,010,038. It most commonly consists of at least one pair of sheets containing separately an electron-donating colorless dye and an electron-accepting compound.

A method of manufacturing capsules is described in U.S. Pat. No. 2.800.
457, a method using coacervation of a hydrophilic colloid sol described in British Patent Nos. 2,800,458, British Patent No. 867.797, British Patent No. 950,443, British Patent No. 98
Examples include the interfacial polymerization method described in US Pat. No. 9,264 and US Pat. No. 1,091,076, and the method described in US Pat.

The capsule wall material is preferably a synthetic resin wall material, for example, a polyurethane and/or polyurea material, or a melamine resin material.

In general, electron-donating colorless dyes are used alone or in combination as solvents (alkylated naphthalene, alkylated diphenyl, alkylated diphenylmethane, alkylated terphenyl, alkylated terphenyl, etc.).
Synthetic oils such as chlorinated paraffin, vegetable oils such as cotton oil and castor oil, animal oils, mineral oils, or mixtures thereof) are dissolved in microcapsules to produce paper, high-quality paper, plastic sheets, resins, etc. A coloring agent sheet is obtained by applying it to coated paper or the like.

In addition to the electron-donating colorless dye, ultraviolet absorbers, antioxidants, and the like may be added as additives to the microcapsules. In particular, from the viewpoint of improving the stability of the electron-donating colorless dye in the capsule before use and the coloring of the capsule, benzotriazole-based ultraviolet absorbers, hindered amine-based antioxidants, hindered phenol-based antioxidants, aniline-based oxidants, etc. It is preferable to add an inhibitor, a quinoline antioxidant, etc.

In addition, an electron-accepting compound and optionally additives may be dispersed in a binder such as styrene-butadiene latex or polyvinyl alcohol, and used together with the pigment described below to produce paper, plastic sheets, resin-coated paper, etc. A developer sheet is obtained by coating the support.

The amounts of the electron-donating colorless dye and the electron-accepting compound to be used depend on the desired coating thickness, the form of the pressure-sensitive recording paper, the capsule manufacturing method, and other conditions, and may be appropriately selected depending on the conditions. This amount can be easily determined by one skilled in the art.

When used for thermal paper, JP-A-62-144.989
No. 62-244,883, etc. Specifically, the electron-donating colorless dye and the electron-accepting compound are 1Oμ or less in the dispersion medium.
It is preferably used after being pulverized and dispersed to a particle size of 3 μm or less. As the dispersion medium, an aqueous polymer solution having a concentration of about 0.5 to 10% is generally used, and dispersion is carried out using a ball mill, sand mill, horizontal sand mill, attritor, colloidal mill, or the like.

The ratio of the electron-donating colorless dye to the electron-accepting compound used is preferably between 10 and 1:1, more preferably between 1.5 and 2.3 by weight. At that time, it is preferable to use a thermofusible substance in combination. These are used in finely dispersed form at the same time as the electron-donating colorless dye or simultaneously with the electron-accepting compound. These are added at a weight ratio of 20% to 300%, particularly preferably 40% to 150%, based on the electron-accepting compound.

Additives may be added to the thus obtained tympanic fluid as necessary to meet various requirements. Examples of additives include dispersing oil-absorbing substances such as inorganic pigments and polyurea fillers in the binder to prevent the recording head from becoming dirty during recording, and also to improve the releasability of the head. For this reason, fatty acids and metal soaps are added. Therefore, in addition to electron-donating colorless dyes and electron-accepting compounds that directly contribute to color development, thermofusible substances, pigments, waxes, antistatic agents, ultraviolet absorbers,
Additives such as antifoaming agents, conductive agents, fluorescent dyes, and surfactants are coated on the support to form the recording material.

Furthermore, a protective layer may be provided on the surface of the heat-sensitive recording layer, if necessary. Two or more protective layers may be laminated as necessary. Furthermore, a coating liquid similar to that of a protective layer may be applied to the back surface in order to correct the curl balance of the support or to improve chemical resistance from the back surface. An adhesive may be applied to the back side and a release paper may be further added to form a label.

Usually, the electron-donating colorless dye and the electron-accepting compound are dispersed in a binder and applied. The binder is generally water-soluble, such as polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, epichlorohydrin-modified polyamide, ethylene-
Examples include maleic anhydride copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives, casein, and gelatin. Further, for the purpose of imparting water resistance to these binders, a water resistance agent may be added, or an emulsion of a hydrophobic polymer, specifically, styrene-butadiene rubber latex, acrylic manure emulsion, etc. may be added. The coating solution is applied onto base paper, wood-free paper, synthetic paper, plastic sheet, resin-coated paper, or neutral paper.

Examples of thermofusible substances are disclosed in JP-A-58-57989 and JP-A-58-87094. Examples of such compounds include 2-benzyloxynaphthalene, 4-
Benzylbiphenyl, 1゜2-di-m-tolyloxyethane, 1,2-diphenoxyethane, 1,4-diphenoxybutane, 1-phenoxy-2-p-ethylphenoxyethane, 1-p-methoxyphenoxy- 2-phenoxypropane, 1-phenoxy-2-p-methoxyphenoxypropane, 1.2-bis-p-methoxyphenoxypropane, 1.3-bis-p-methoxyphenoxypropane, 1-p-methoxyphenoxy-2- 〇-chlorophenoxyethane, l-phenoxy-2-p-methoxyphenylthioethane, 1,2-bis-p-methoxyphenylthioethane, 1-p-methylphenoxo 2-p-methoxyphenylthioethane, bis- Ether compounds such as [β-(p-methoxyphenoxy)ethyl]ether, 4-(4-chlorobenzyloxy)ethoxypentene, 4-(p-methoxypencylthio)anisole, stearic acid amide, methylene bisstearate Amide, stearic acid anilide, behenic acid amide, stearic acid anilide, and stearyl urea are available.

Pigments include kaolin, calcined kaolin, talc, diatomaceous earth, calcium carbonate, aluminum hydroxide, magnesium hydroxide, zinc oxide, lithopone, amorphous silica, colloidal silica, calcined stone wax, silica, magnesium carbonate, titanium oxide, alumina. , barium carbonate, barium sulfate, mica, microballoons, urea-formalin fillers, polyester particles, cellulose fillers, etc. are used.

Examples of metal soaps include higher fatty acid polyvalent metal salts, such as zinc stearate, aluminum stearate, calcium stearate, and zinc oleate.

Examples of waxes include paraffin wax, carboxy-modified paraffin wax, carnauba wax, microcrystalline wax, polyethylene wax, polystyrene wax, higher fatty acid esters, amides, and the like.

The hindered phenol compound is preferably a phenol derivative substituted with a branched alkyl group at at least one of the 2 or 6 positions. For example 1. l, 3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1°1.3-tris(2-ethyl-4-
Hydroxy-5-t-butylphenyl)butane, I, 1
．． 3-tris(3,5-t-butyl-4-hydroxyphenyl)butane, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)propane, 4,4-butylidenebis (6-t-butyl-3-methylphenol, 4,4-thiobis(3-methyl-6-t
-butylphenol), 2,2-methylenebis(6-t
-butyl-4-methylphenol), 2,2-methylenebis(6-t-butyl-4-ethylphenol), octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 1 ,3,5-trimethyl-2,4,6-)lis(3,5-di-t-butyl-4
-hydroxybenzyl)benzene, 2,2,6.6-tetramethyl-4-piperidinyl sebacate, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propinate co Examples include methane.

The amount of the hindered phenol compound to be used is preferably 1 to 200% by weight, more preferably 5 to 100% by weight, based on the electron accepting compound.

Examples of ultraviolet absorbers include cinnamic acid derivatives, hensifhenone derivatives, and hensitriazolylphenol derivatives.
For example, α-nonano-β-phenylbutyl oxide, 0
-benzotriazolylphenol, 0-hensitriazolyl-p-chlorophenol, 0-hensitriazolyl-p-methylphenol, 0-benzotriazolyl-2
, 4-'di-t-butylphenol, 0-hensitriazolyl-2,4-di and monooctylphenol.

Water-resistant agents include water-soluble initial condensates such as N-methylol urea, N-methylol melamine, and urea-formalin;
Examples include blend heat treatment of dialdehyde compounds such as glyoxal and glutaraldehyde, inorganic crosslinking agents such as boric acid and borax, polyacrylic acid, methyl vinyl ether-maleic acid copolymer, isobutylene-maleic anhydride copolymer, etc. .

Materials used for the protective layer include polyvinyl alcohol,
Carboxy-modified polyvinyl alcohol, vinyl acetate-acrylamide copolymer, silicon-modified polyvinyl alcohol, starch, modified starch, methylcellulose, carboxin methylcellulose, hydroxymethylcellulose, gelatins, gum arabic, casein, styrene-maleic acid copolymer hydrolyzate , styrene-maleic acid copolymer half ester hydrolyzate, isobutylene-maleic anhydride copolymer hydrolyzate, polyacrylamide derivatives, polyvinylpyrrolidone, polystyrene sulfone sodium chloride, sodium alginate, and other water-soluble polymers, and styrene-
Water-insoluble polymers such as butadiene rubber latex, acrylonitrile-butadiene rubber latex, methyl acrylate-butadiene rubber latex, and vinyl acetate emulsion are used.

In addition, pigments, metal soaps, waxes, waterproofing agents, etc. may be added to the protective layer for the purpose of improving matching properties with the thermal head.

Further, when coating the protective layer on the thermosensitive coloring layer, a surfactant may be added in order to obtain a uniform protective layer. As the surfactant, a sulfosuccinic acid-based alkali metal salt, a fluorine-containing surfactant, etc. are used. Specifically, G (
Sodium salts or ammonium salts such as n-hexyl)sulfosuccinic acid and di(2-ethylhexyl)sulfosuccinic acid are preferred, or anionic surfactants are effective.

The electrically conductive thermal paper is manufactured, for example, by the method described in JP-A-49-11344 and JP-A-50-48930. Generally, a coating liquid containing a conductive substance, an electron-donating colorless dye, and an electron-accepting compound dispersed together with a binder is applied to a support such as paper, or a conductive substance is applied to the support to form a conductive layer. Electrifying thermal paper is manufactured by applying a test solution containing an electron-donating colorless dye, an electron-accepting compound, and a binder dispersed thereon. Note that the sensitivity can also be improved by using the thermofusible substance described above in combination.

The photosensitive pressure sensitive paper is manufactured, for example, by the method described in JP-A-57-179836. In general, photopolymerization initiators such as silver bromide, silver bromide, silver behenate, Michler's ketone, benzoin derivatives, and benzophenone derivatives are combined with polyfunctional monomers such as polyallyl compounds, poly(meth)acrylates, and poly(meth)acrylamides. The crosslinking agent is encapsulated in a synthetic resin capsule such as polyether urethane or polyurea together with an electron-donating colorless dye and, if necessary, a solvent. After imagewise exposure, the unexposed area is colored by contacting with an electron-accepting compound using an electron-donating colorless dye.

The electron-donating colorless dye according to the present invention has, for example, the following general formula (■) or (IV) Ar1-CR1=CR2-CR3=Ar2" Y-(
Using I[) as a raw material, HCRs RI R,, HPO(
OR1)! , HNRs C0RI. Or it can be obtained by reacting with its salt.

In the above formula, Ar+, A r t , RI-R16 have the above-mentioned meanings, and Y- represents an anion of an inorganic acid or an inorganic acid necessary to form a dye, such as a chlorine ion, a bromide ion, a fluorine ion, Sulfate ion, phosphate ion, perchlorate ion, acetate ion, benzenesulfonate ion, p-4
Examples include luenesulfonic acid ion and methylsulfate ion.

The aforementioned HCRs RI R? , HPO(ORs)x
, HNRs COR,. The salts are, for example, alkali metal salts, alkaline earth metal salts, ammonium salts or amine salts.

HCRs used Rs R1, HPO (OR-),
, HNRs C0RI. Or the amount of salt is the general formula (■)
It is preferably 1 to 3 mol, particularly preferably 1 to 1.5 mol, per 1 mol of the compound (IV).

The above reaction is preferably carried out in an organic solvent, such as alcohols, ethers, esters, aromatic hydrocarbons, halogenated hydrocarbons, and the like. Specific examples include methanol, ethanol, isopropanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, dioxane, ethyl acetate, toluene, xylene, methylene chloride, and the like. Among these, polar organic solvents are particularly preferred.

The amount of organic solvent used is preferably 10% or more, particularly 20% of the solid content.

As a catalyst, an acidic catalyst such as an aliphatic carboxylic acid such as formic acid or acetic acid or an inorganic acid such as hydrochloric acid, sulfuric acid, phosphoric acid or perchloric acid may be added.

The reaction temperature is preferably 10 to 100°C, particularly 20 to 100°C.
70°C is preferred.

It is also preferable to carry out the reaction under an atmosphere of an inert gas such as nitrogen or argon gas from the viewpoint of preventing coloration of the liquid.

(Synthesis Example) The compound of Example (5) was added to a three-bottle flask equipped with a stirrer, and l-ethyl-2
-Methylindole 0. 4 mol, l, 1.3
,3-tetraethoxypropane0. 2 Weigh out 200% of mob acetic acid, and add 0.41 mol of 70% perchloric acid dropwise while stirring at room temperature. 90°C after completion of dripping
Stir for 6 hours. The reaction mixture was poured into ice water, and the precipitated crystals were filtered, washed with water, and washed with toluene to form the following compound (V
) obtained.

Next, in a three-bottle flask with another stirrer, 60%
Weigh out 0.011 mol of sodium hydride and 40 tnl of tetrahydrofuran, and while stirring, add 0.0105 mol of dimethyl malonate dropwise. After stirring at room temperature for 5 minutes, 0.01 mol of compound (v) is gradually added, and the mixture is stirred at room temperature for 1 hour. The reaction mixture was poured into water, filtered, and dried to obtain the desired product as pale yellowish white crystals, which had a lambda 4.1 of 567 nm in 95% acetic acid.

(Examples of the Invention) Examples are shown below, but the present invention is not limited thereto. % represents weight % unless otherwise specified.

(Example 1) 20 g each of the compound of Example (1) which is an electron-donating colorless dye, hisphenol A which is an electron-accepting compound, and 4-(4-chlorobenzyloxy)ethoxybenzene which is a thermofusible substance. were dispersed with Ioog's 5% polyvinyl alcohol (Clary PV Al05) aqueous solution in a hole mill for one day and night to make the volume average particle size 1.5 μm or less, and each dispersion was obtained. Further, 80 g of calcium carbonate was dispersed with 160 g of a 0.5% solution of sodium hexametaphosphate using a homogenizer to obtain a pigment dispersion.

Each of the dispersions prepared as described above was mixed in a ratio of 5 g of an electron-donating colorless dye dispersion, 10 g of an electron-accepting compound dispersion, 10 g of a thermofusible substance dispersion, and 15 g of a pigment dispersion,
Further, 3 g of a 21% zinc stearate emulsion was added to obtain a heat-sensitive coating liquid. This coating liquid was applied to high-quality paper using a coating bar so that the dry weight of the coating layer was 5 g/m', and after drying at 50°C for 1 minute, a super calender was applied to heat-sensitive recording paper. Obtained.

The obtained thermal recording paper was free from fog during raw storage and had excellent stability over time.

Thermal recording paper is heated using a thermal head (KLT) manufactured by Kyocera Corporation.
-216-8MPDI) and 100kg just before the head.
In a thermal printing experimental device with a pressure roll of /crl,
When printing was performed with a pulse width of 1.0 while using a pressure roll under conditions of a head voltage of 24 V and a pulse cycle of 1 orns, a purple image was obtained. Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

(Examples 2 to 3) In place of the electron-donating colorless dye and electron-accepting compound of Example 1, the following were used, respectively. A coated paper was obtained in the same manner as in Example 1 in other respects.

Example 2 Electron-donating colorless dye, 10 g of the compound of specific example (23),
Crystal violet lactone 10g Electron-accepting compound: 4-hydroxyphenyl-4°-1so-propoxyphenylsulfone 5g 10 Danzinc benzimidazole complex 15g Example 3 Electron-donating colorless dye - Compound of Example (4) lOg, 3
-(1-n-octyl-2-methylindol-3-yl')-3-(4-N,N-diethylamino-2=ethoxyphenyl)phthalide 10 Electron-accepting compound: 1.1
-Bis(4-hydroxyphenyl)cyclohexane 8g
8 g of zinc 14-β-p-methoxyphenoxyethoxysalicylate, 4 g of 1-phenyl-2,3-dimethyl-3-viraprin-5-one complex of zinc rhodan In each case of Examples 2 to 3, the coloring obtained The image (blue to blue-violet) showed good resistance to chemicals, sunlight, etc.

(Example 4) (1) Preparation of capsule sheet containing electrotoxic colorless dye 5 parts of a partial sodium salt of polyvinylbenzenesulfonic acid (manufactured by Nasoional Starch Co., Ltd., VER3A, TL500) was dissolved in 95 parts of hot water and then cooled. do. A sodium hydroxide aqueous solution was added to this to adjust the pH to 4.0. On the other hand, 100 parts of diisopropylnaphthalene in which 365% of the compound of Example (5) was dissolved was emulsified and dispersed in 100 parts of a 5% aqueous solution of a partial sodium salt of the polyvinylbenzenesulfonic acid to form an emulsion having a particle size of 4.0 μm in diameter. I got the liquid.

Separately, 6 parts of melamine, 11 parts of a 37% by weight formaldehyde aqueous solution, and 30 parts of water were heated and stirred at 60°C, and after 30 minutes, a transparent aqueous solution of a melamine-formaldehyde prepolymer was obtained.

This aqueous solution was mixed with the above emulsion. While stirring, the pH was adjusted to 6.0 with a 2M phosphoric acid solution, the temperature of the solution was raised to 65°C, and stirring was continued for 6 hours. This capsule liquid was cooled to room temperature and adjusted to pH 9.0 with an aqueous sodium hydroxide solution.

To this dispersion, 200 parts of a 10% by weight aqueous solution of polyhinyl alcohol and 50 parts of starch particles were added and water was added to prepare a solution of a microcapsule dispersion with a solid content concentration of 20%.

This coating liquid was applied to a base paper of 50 g/rn2 using an air knife coater so that a solid content of 5 g/m' was applied.
After drying, a capsule sheet containing an electron-donating colorless dye was obtained.

(2) Preparation of electron-accepting compound sheet 3.5-bis-α-methylpencilsalicylic acid zinc salt 1
0 part was added to 20 parts of 1-isopropylphenyl-2-phenylethane and dissolved. This was mixed with 50 parts of a 2% aqueous solution of borihinyl alcohol and 0.1 part of a 1O% aqueous solution of todesolbenzenesulfonic acid triethanolamine salt, and emulsified to give an average particle size of 3 μm.

Next, a dispersion consisting of 80 parts of calcium carbonate, 20 parts of zinc oxide, 1 part of sodium hexametaphosphate, and 200 parts of water was added to the suspension mixed with the above emulsion, and 100 parts of a 10% PVA aqueous solution and carboxylic acid were added as a binder. Modified SBR
10 parts of latex (as solid content) was added and water was added to the solid content to give a coating liquid (A).

Next, 10 parts of the electron-accepting compound, 20 parts of Jilton clay
A dispersion containing 60 parts of calcium carbonate, 20 parts of zinc oxide, 1 part of sodium hexametaphosphate, and 200 parts of water was dispersed with a sand grinder so that the average particle size was 3 μm.

Add 16 parts of 10% PVA aqueous solution and 10% PVA to this dispersion.
100 parts of the aqueous solution and 10 parts of carboxy-modified SBR latex (as solid content) were added, and water was added to make the solid content concentration 20% to obtain a coating liquid (B).

Coating liquid (A) and coating liquid (B) were mixed 1:1 in terms of electron-accepting compound, and 5.0 g/m was applied to 50 g/m' base paper.
The solid portion of Step 2 was coated in a tube using an air knife coater and dried to obtain an electron-accepting compound sheet.

The surface of the microcapsule sheet containing an electron-donating colorless dye is
When the electron-accepting compound sheet was stacked and a load of 600 kg/d was applied, the color immediately developed into purple. Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

(Example 5) In place of the electron-donating colorless dye of Example 4, specific example (1
An electron-donating colorless dye-containing microcapsule sheet was obtained in the same manner as in Example 4, except that the compound 4) was used. Lay this sorted side on the electron-accepting compound sheet of Example 4 6
When a load of 0.00 kg/cd was applied, the color quickly developed to purple. Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

(Example 6) The following was used in place of the electron-accepting compound sheet of Example 4.

(2″) Adjustment of electron-accepting compound sheet Acidic clay 100
were dispersed in 400 parts of a 0.5% aqueous sodium hydroxide solution, followed by adding 20 parts of styrene-butanoene copolymer latex (solid content) and 40 parts of a 10% starch aqueous solution, and thoroughly stirring and mixing to obtain an electron-accepting solution. A compound coating solution was obtained.

5. Apply the coating solution prepared in this way to 50 g/m' base paper.
It was coated using an air knife coater so that a solid content of 0 g/m' was coated and dried to obtain an electron-accepting compound sheet.

On this electron-accepting compound sheet, the surface of the electron-donating colorless dye-containing microcapsule sheet of Example 4 was layered for 600 kg.
When a load of g/cd was applied, a purple color immediately developed. Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

(Example 7) In place of the electron-donating colorless dye of Example 4, specific example (1
An electron-donating colorless dye-containing microcapsule sheet was obtained in the same manner as in Example 4 except that the compound 3) was used. This sheet surface was stacked on the electron-accepting compound sheet of Example 6 for 60 minutes.
When a load of 0 kg/cd was applied, a purple color developed.

Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

(Example 8) In place of the electron-donating colorless dye of Example 4, specific example (2
An electron-donating colorless dye-containing microcapsule sheet was obtained in the same manner as in Example 4, except that the compound No. 0) and crystal violet lactone (weight ratio: 21) were used. This sheet surface was stacked on the electron-accepting compound sheet of Example 6 for 600k.
When a load of g/al was applied, a bluish-purple color developed. Moreover, the obtained colored image showed good resistance to chemicals, sunlight, etc.

Claims (2)

[Claims] (1) A recording material that utilizes color development due to contact between an electron-donating colorless dye and an electron-accepting compound, characterized in that a compound represented by the following general formula (I) is used as the electron-donating colorless dye. Recording materials ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ (I) In the above formula, Ar_1 and Ar_2 are heterocyclic groups, R_1 to R_
3 is a hydrogen atom, an alkyl group, a phenyl group, R_4 is -
CR_5R_6R_7, -PO(OR_3)_2, -N
R_8COR_1_0 (R_5 to R_1_0 represent a hydrogen atom or a monovalent group. However, at least one of R_5 to R_7 represents an electron-withdrawing group). (2) Ar_1 and Ar_2 in general formula (I) represent the following general formula (II), ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) R_1_1 and R_1_2 represent hydrogen atoms, alkyl groups, and aryl groups, R_1_3 is a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a cyano group, a nitro group, a substituted amino group, a hydroxy group, a halogen atom,
alkoxycarbonyl group, aryloxycarbonyl group, acyloxy group, m is an integer from 1 to 4, R_5~
R_7 is a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a halogen atom, a cyano group, a nitro group, SO_2R
_1_4, COR_1_5, NR_1_6R_1_7 [R_1_4, R_1_5 are hydrogen atoms, alkyl groups, aryl groups, heterocyclic groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, hydroxy groups, N
R_1_8R_1_9, R_1_6 to R_1_9 are hydrogen atoms, alkyl groups, aryl groups, heterocyclic groups, SO_2
R_2_0, COR_2_1 (R_2_0, R_2_1
represents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group], and R_8 represents a 4- to 12-membered ring structure in which R_6 and R_7 are connected to each other and may contain a hetero atom.
represents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group; cyclic group, hydroxy group, COR_2_
2, R_1_0 and R_2_2 may be a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group, and R_9 and R_1_0 may be linked to each other and contain a heteroatom 4 to 12
A recording material characterized by using the compound according to claim 1, which exhibits a membered ring structure.