JPH02117882A - Recording material - Google Patents

Abstract

PURPOSE:To enhance light resistance before use by using as an electron-donative colorless dye, a bisindolylphthalide compound in which at least one indole has, at the 1-position thereof, an alkyl or aryl group having a substd. amino group. CONSTITUTION:A bisindolylphthalide compound preferable for use as an electron-donative colorless dye in a recording material utilizing color formation by contact of the electron-donative colorless dye with an electron-acceptive compound, is a compound of formula (I), wherein R is an alkylene or arylene, each of R1 and R2 is hydrogen, an alkyl, aryl or acyl, R3 is hydrogen, an alkyl, aryl or -R-NR1R2-, each of R4 and R5 is hydrogen, an alkyl or aryl, each of R6 and R7, is hydrogen, an alkyl, alkoxyl, halogen, nitro or substd. amino, and ring A is an aromatic ring. The electron-acceptive compound may be a phenol derivative, a salicylic acid derivative, acid clay, bentonite, a novolak resin or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to recording materials, and more particularly to recording materials with improved light resistance before use.

(Prior Art) Recording materials using electron-donating colorless dyes and electron-accepting compounds are already well known as pressure-sensitive paper, thermal paper, light-sensitive 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. Patent No. 4436920, Japanese Patent Publication No. 60-23992, Japanese Unexamined Patent Publication No. 57
-179836, 60-123556, 60-12
I am familiar with 3557 etc.

In recent years, with the diversification of requirements for recording systems, research into multicolor recording has been intensively conducted. Among these, bisindolyl phthalide compounds are known as compounds that develop a red to magenta color. However, this compound has drawbacks. For example, 3.3-bis(1-n-octyl-2-methylindol-3-yl) phthalide develops quickly and exhibits a deep magenta color, but recording materials using this compound have poor light resistance before use. , the skin becomes yellow due to photodecomposition products.

The present inventors have investigated the oil solubility, solubility in water, partition coefficient, pKa, polarity of substituent, position of substituent, crystallinity when mixed, for each of the electron donating colorless dye and the electron accepting compound. Focusing on characteristics such as changes in solubility, we have pursued the development of good materials for recording materials and recording materials.

(Object of the Invention) Therefore, an object of the present invention is to provide a recording material using a material that satisfies light resistance before use and 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. This has been achieved using a recording material characterized by using a bisindolyl phthalide compound which is an alkyl group or an aryl group having a substituted amino group.

The above-mentioned substituted amine group represents an amino group in which at least one of the substituents is an alkyl group.

Preferred compounds of the present invention are shown in general formula (1).

In the above formula, R represents an alkylene group or an arylene group, and R1R2 represents a hydrogen atom, an alkyl group, an aryl group, or an acyl group (however, when R is an arylene group, R.

represents an alkyl group. ), R3 is a hydrogen atom, an alkyl group, an aryl group or -RNR+ Rz , R1, R3
represents a hydrogen atom, an alkyl group, an aryl group, Rs , Rq
represents a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a nitro group, or a substituted amino group, and is commonly used to represent an aromatic ring.

In addition, an alkyl group represents a saturated, unsaturated or cycloalkyl group, and these have a substituent such as an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, a halogen atom, an acylamino group, an aminocarbonyl group, or a cyano group. You can leave it there.

In addition, the aryl group represents a phenyl group, a naphthyl group, or a heterocyclic group, and these include an alkyl group, an alkoxy group,
Substituents such as aryloxy group, halogen atom, nitro group, cyan group, substituted carbamoyl group, substituted sulfamoyl group, substituted amino group, substituted oxycarbonyl group, substituted oxysulfonyl group, alkylthio group, arylsulfonyl group, or phenyl group may have.

Among the substituents represented by R+ and R2 in the above formula, hydrogen atoms, alkyl groups having 1 to 18 carbon atoms, aryl groups having 6 to 12 carbon atoms, and acyl groups having 1 to 18 carbon atoms are preferred; is a halogen atom, an alkoxy group, an aryl group, an aryloxy group, an alkyl group, an acyl group,
It may be substituted with a cyano group, hydroxy group, furfuryl group, etc. (However, if R is an arylene group, % R1
represents an alkyl group. ) R1 and R2 are bonded to each other to form a 5- to 8-membered ring, such as piperidine, morpholine, pyrrolidine, piperazine,
A ring such as hexamethyleneimine, caprolactam, or indole may be formed.

R1 and R2 are more preferably an alkyl group having 1 to 8 carbon atoms or an aryl group having 6 to 10 carbon atoms.

R1 and R2 are hydrogen atoms, methyl groups, ethyl groups, n
-propyl group, n-butyl group, iso-butyl group, n
-amyl group, 1so-amyl group, n-hexyl group, n-
heptyl group, n-octyl group, 2-ethylhexyl group,
n-dodecyl group, n-octadecyl group, nidoxyethyl group, phenyl group, 4-methylphenyl group, benzyl group,
Examples include phenethyl group and acetyl group.

Among the substituents represented by R in the above formula, those having 1 to 1 carbon atoms
8 alkylene groups and arylene groups having 6 to 12 carbon atoms are preferred, and these are -CO2-5○2--8〇--
S--O- CO-OCO2N HCON HN HCO2C0NHCHOH- may be connected.

R is C-H2N(Z CP R2-)rCP H2N
(Z CX H2y) r Z CP H2
Those represented by N are more preferred.

Here, p, q, x, y are integers from 1 to 18, r is an integer from 0 to 4, and 2 is -CO2--S○2SO--S--
〇--CO- OCOa N HCON HN HC02
-CONH--CHoH-.

As a preferable example of C-R2, -Q(,
--(CH2), --to--(CH2), --(CH2)1o-, etc. are mentioned.

Among the substituents represented by R3 in the above formula, a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 12 carbon atoms, or -R-NR, R2 is preferable (R, Ra
, Rz as described above).

R1 is a hydrogen atom, methyl group, ethyl group, n-butyl group, l5O-butyl group, n-amyl group, l5O-amyl group, n-hexyl group, n-heptyl group, n-octyl group, 2- Ethylhexyl group, n-dodecyl group, n-octadecyl group, ethoxyethyl group, phenoxyethyl group, phenyl! , 4-methoxyphenyl group, benzyl group,
Examples include phenethyl group.

Among the substituents represented by R4 and Rs in the above formula, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms are preferred.

Examples of Ra and Rs include a hydrogen atom, a methyl group, an ethyl group, and a phenyl group.

Among the substituents represented by Rs and R7 in the above formula, hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, and 1 carbon atom
to 12 alkoxy groups, chlorine atoms, bromine atoms, nitro groups, mono- or dialkylamino groups having 1 to 12 carbon atoms, and monoacylamino groups having 1 to 12 carbon atoms are preferred.

inside ring A is preferred. R, is selected from the groups represented by R6.

n is an integer from 1 to 6, R is -O--5-NR+o-
represents. RIO is a hydrogen atom, an alkyl group, an alkyl group,
Represents an acyl group.

is preferable from the viewpoint of synthetic handling and color development.

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

(1) 3.3-bis(1-(4-dimethylaminophenoxyethyl)-2-methylindol-3-yl)phthalide (2) 3.3-bis(1-(4-diethylaminophenoxyethyl)-2 -Methylindol-3-yl)phthalide (3) 3.3-bis(1-(4-di-n-butylaminophenoxyethyl)-2-methylindol-3-yl)phthalide (4) 3.3- Bis(1-(3-diethylaminophenoxyethyl)-2-methylindol-3-yl)phthalide (5) 3.3-bis(1-(3-N-ethyl-N-Is)
O-amylaminophenoxyethyl)-2phenylindol-3-yl)phthalide (6) 3,3-bis(1-
(4-di-n-octylaminophenoxybutyl)-2
-methylindol-3-yl)-4- or -7-azaphthalide (7) 3-(1-n-octyl-2-methylindol-3-yl)-3-(1-(3-diethylaminophenoxyethyl) -2-methylindol-3-yl)phthalide (8) 3.3-bis(1-(N-ethyl-N-phenylaminoethyl)-2-methylindol-3-yl)phthalide (9) 3.3 -bis(1-diethylaminoethyl-2-
Methylindol-3-yl)phthalide αQ 3,3-
Bis(1-(4-diethylaminophenyl)-2-methylindol-3-yl)-4,7-diazaphthalide Ql)3-(1-n-octyl-2-methylindol-3-yl") -3- (1-(4-di-n-butylaminophenyl)-2-methylindol-3-yl)phthalide These colorless dyes are also known as triphenylmethane phthalide compounds, fluoran compounds,
Recording materials can be produced 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. It can also be assembled.

In this case, it is preferable to use the above-mentioned colorless dye in an amount of 40% or more from the viewpoint of improving properties.

Regarding these, for example, specific examples of phthalides are U.S. Patent Reissue No. 23.024 and U.S. Patent Specification No. 3.
．． No. 491.111, No. 3,491.112, No. 3.491,116, and No. 3.509,174, and specific examples of fluorans are given in U.S. Patent Specification No. 3,624.
, No. 107, No. 3,627,787, No. 3. ,,
641. No. 011, No. 3,462,828, No. 3,681.390, No. 3,920,510, No. 13.959.571, and specific examples of spirodipyrans are given in U.S. Patent Specification No. 3. , 971.808; pyridine and pyrazine compounds are described in U.S. Patent No. 3,775;
．． No. 424, No. 3,853゜869, No. 4.24
No. 6,318, specific examples of fluorene compounds are given in Japanese Patent Application No. 6, 1983.
1-240989, etc.

Examples of electron-accepting compounds that impart color upon contact with colorless dyes include common compounds such as phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids, acid clay, bentonite, novolac resins, metal-treated novolac resins, and metal complexes. are used, and these may be used in combination. Examples of these are Tokuko No. 9309, No. 40-9309, and Tokuko No. 4
5-14039, JP 52-140483, JP 48-51510, JP 57-210886,
JP-A-58-87089, JP-A-59-11286, JP-A-60-176795, JP-A-61-9598
No. 8, U.S. Patent No. 3,767.449, U.S. Patent No. 4
, No. 219.219, No. 4.269,893, No. 4,374.671, No. 4,687,869, etc. In particular, combinations with salicylic acid derivatives and phenol derivatives are preferred.

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 fields of recording materials and polymer resins, such as pigments, waxes, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, and fluorescent agents, are used. Additives such as dyes and surfactants are used.

For use with pressure sensitive paper, U.S. Patent No. 2,505.47
No. 0, No. 2,505,471, No. 2゜505.489
No. 2,548.366, No. 2.712,507, No. 2,730,456, No. 2,730.457,
It can take 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.

For a method of manufacturing capsules, see U.S. Patent No. 2800.4.
57, a method using coacervation of a hydrophilic colloid sol described in British Patent No. 867.797, British Patent No. 950.443, British Patent No. 989.
, No. 264, No. 1091.076, and the method described in US Pat. No. 3,103,404.

The capsule wall material is preferably a synthetic resin-based wall material, for example, a polyurethane and/or polyurea-based material, or a melamine resin-based 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, etc.) are dissolved in microcapsules to produce paper, high-quality paper, plastic sheets, resin coatings, etc. A coloring agent sheet is obtained by applying it to ted paper, etc.

Since the coloring agent of Honhatko has good solubility in synthetic oils such as alkylated naphthalene, alkylated diphenyl, and alkylated diphenylalkane, it has the advantage that it can be used in combination with paraffinic oils, etc., which have low solubility.

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. It is easy for one skilled in the art to determine this amount to use.

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 10μ 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 1:10 and 1:1 by weight, and particularly preferably between 1:5 and 2:3. 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% or more and 300% or less, particularly preferably 40% or more and 150% or less, based on the electron-accepting compound.

Additives may be added to the thus obtained coating liquid 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 staining of the recording head during recording. Fatty acids, metal soaps, etc. are added to increase the coloring.Therefore, in addition to electron-donating colorless dyes and electron-accepting compounds that directly contribute to color development, thermofusible substances, pigments, waxes, and antistatic agents are generally added. , UV absorber,
Additives such as antifoaming agents, conductive agents, fluorescent dyes, and surfactants are coated onto 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. Water-soluble binders are generally used, such as vorivinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, epichlorohydrin-modified polyamide, and ethylene-
Examples include maleic anhydride copolymer, styrene-maleic anhydride copolymer, inbutylene-maleic anhydride copolymer, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives, casein, gelatin, etc. . 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 resin emulsion, etc. may be added. The coating liquid 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, di-m-)lyloxyethane 1
．． 1.2-diphenoxyecune, 1,4-diphenoxybutane, bis-[β-(p-methoxyphenoxy)ethyl ether, 1-phenoxy-2-p-ethylphenoxyethane, 1-p-methoxyphenoxy -2-phenoxypropane, niphenoxy-2-p-methoxyphenoxypropane, 1,2-bis(p=methoxyphenoxy)propane, 1,3-bis(p-methoxyphenoxy)propane, 1-p-methoxyphenoxy- 2-o-chlorophenoxyethane, 4-(p-methoxybenzylthio)anisole, ■-phenoxy 2-p-methoxyphenylthioethane, 1,2-bis(p-methoxyphenylthio)ethane, ■-p- Methylphenoxy 2-p
- ether compounds such as methoxyphenylthioethane,
Examples include stearic acid amide, methylene bisstearamide, stearic acid anilide, behenic acid amide, stearic acid anion/do, and stearyl urea.

Pigments include kaolin, calcined kaolin, talc, waxite, diatomaceous earth, calcium carbonate, aluminum hydroxide,
Magnesium hydroxide, zinc oxide, lithopone, amorphous silica, colloidal silica, calcined gypsum, silica, magnesium carbonate, titanium oxide, alumina, barium carbonate, barium sulfate, mica, microballoon, urea-formalin filler polyester particles, Cellulose filler or the like is used.

Examples of metal soaps include polyvalent metal salts of higher fatty acids, 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.

As the bound phenol compound, a phenol derivative in which at least one of the 2nd and 6th positions is substituted with a branched alkyl group is preferred. For example 1.1.3-)lis(2-methyl-4-hydroxy-5-t-butylphenyl)butane, l.

1.3-) Lis(2-ethyl-4-hydroxy-5-t
-butylphenyl)butane, 1,1,3-tris(3,
5-di-t-butyl-4-hydroxyphenyl)butane, 1. I, 3-tris(2-methyl-4-hydroxy-
5-tert-butylphenyl)propane, 4.4-butylidenebis(6-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)propione-+-11,3,5-trimethyl-2,4,6-
tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis[methylene-3-(3,5
-dibutyl-4-hydroxyphenyl)propinate comethane, 2.2.6.6-tetramethyl-4-piperidinyl sebacate, and the like.

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.

As ultraviolet absorbers, cinnamic acid derivatives, benzophenone derivatives, benzotriazolylphenol derivatives, etc.
For example, butyl α-cyano-β-phenylcinnamate, 0
-benzo) IJ azolylphenol, O-benzotriazolyl-p-chlorophenol, 0-benzotriazolyl-2,4-di-t-butylphenol, 0-benzotriazolyl-2,4-di- Examples include t-octylphenol.

On the water-resistant side, water-soluble initial condensates such as N-methylol urea, N-methylol melamine, urea-formalin, etc.
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, carboxymethylcellulose, hydroxymethylcellulose, gelatins, gum arabic, casein, styrene-maleic acid copolymer hydrolyzate, Water-soluble polymers such as styrene-maleic acid copolymer half ester hydrolyzate, inbutylene-i-water maleic acid copolymer hydrolyzate, polyacrylamide derivatives, polyvinylpyrrolidone, polystyrene sodium sulfonate, sodium alginate, 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, but anionic surfactants are effective.

The electrically conductive thermal paper is manufactured by the method described in, for example, Japanese Patent Application Laid-open No. 49-11344 and Japanese Patent Application Laid-Open No. 50-48930. Generally, a coating liquid in which a conductive substance, an electron-donating colorless dye, and an electron-accepting compound are 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, and then a conductive layer is formed on the support. The electrically conductive thermal paper is manufactured by applying a coating liquid in which an electron-donating colorless dye, an electron-accepting compound, and a binder are dispersed. Note that the sensitivity can also be improved by using the thermofusible substance described above in combination.

The photosensitive pressure sensitive paper is manufactured by the method described in, for example, Japanese Patent Application Laid-open No. 179836/1983. Generally silver bromide, silver bromide, silver behenate, Michlerskaton, Hentuin mL
A photopolymerization initiator such as benzophenone m-conductor and a polyfunctional monomer such as polyallyl compound, poly (meth)
A crosslinking agent such as acrylate or poly(meth)acrylamide 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 is produced by known methods (for example, US Pat. No. 4,062,866, British Patent No. 1,422,096, etc.). For example, a corresponding indole derivative and an aromatic dicarboxylic acid anhydride, or a corresponding indole carbonyl-aromatic carboxylic acid and an indole derivative, acetic anhydride, sulfuric acid,
In the presence of a condensing agent such as phosphorus oxychloride, 40-130
The reaction is carried out for 1 to 5 hours at a temperature of °C.

Synthesis Example 3.3-bis(1-(4-di-n-butylaminophenoxyethyl)-2-methylindol-3-yl)phthalide In a three-necked flask equipped with a stirrer, 2-(1-(4
-di-n-butylaminophenoxyethyl)-2-methylindol-3-yl)carbonyl-benzoic acid 0.1
M, 1-(4-di-n-butylaminophenoxyethyl)-2-methylindole O, IM, acetic anhydride 0.3
Measure out 30ml of M, acetonitrile, and stir at 65°C for 3 hours. The reaction mixture is poured into water and made alkaline with aqueous sodium hydroxide solution. This reaction mixture is purified using a silica gel column to obtain the desired product with a melting point of 132-3°C.

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

(Examples 1 to 4) (1) Preparation of capsule sheet containing electron-donating colorless dye 5 parts of a partial sodium salt of polyvinylbenzenesulfonic acid (manufactured by National Starch Co., Ltd., VER3ASTL500) is dissolved in 95 parts of hot water and then cooled. . 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 3.5% of the electron-donating colorless dye shown in Part 1 was dissolved was emulsified and dispersed in 100 parts of a 5% aqueous solution of the partial sodium salt of polyvinylbenzenesulfonic acid, and the particles had a particle size of 4.0 μm in diameter. An emulsion was obtained.

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 polyvinyl alcohol aqueous solution 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 50 g/m2 base paper using an air knife coater so that the solid content was 5 g/m2, and dried to obtain a capsule sheet containing an electron-donating colorless dye.

(2) Preparation of electron-accepting compound sheet 3.5-bis-α-methylbenzylsalicylic acid subtlL
10 parts were added to 20 parts of 1-isopropylphenyl-2-phenylethane and dissolved. This was mixed with 50 parts of a 2% polyvinyl alcohol aqueous solution and 0.1 part of a 10% dodecylbenzenesulfonic acid trienolamine salt aqueous solution and emulsified so that the average particle size was 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 mixed with the above emulsion, and 100 parts of a 10% PVA aqueous solution as a binder and carboxy-modified SBR
A coating liquid (A>) was obtained by adding 10 parts of latex (based on solid content) and adding water so that the solid content concentration was 20%.

Next, a dispersion consisting of 10 parts of the color developer, 20 parts of Jilton clay, 60 parts of calcium carbonate, 20 parts of zinc oxide, 1 part of sodium hexametaphosphate, and 200 parts of water was ground in a sand grinder until the average particle size was 3 μm. It was dispersed like that.

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

Coating liquid (A>) and coating liquid (B) were mixed at a ratio of 1:1 in terms of color developer, and coated with an air knife coater so that a solid content of 5.0 g/m2 was coated on a 50 g/m2 base paper. Apply at
It was dried to obtain a color developer sheet.

The surface of the microcapsule sheet containing an electron-donating colorless dye is
Layered on electron-accepting compound sheet 600kg/m2
When a load of 100% was applied, all of them quickly developed a magenta color. Further, even when the surface of the electron-donating colorless dye-containing microcapsule C) was irradiated with a 320,001 ux fluorescent lamp for 16 hours before use, no yellowing of the skin was observed. Furthermore, the light fastness of the obtained image was excellent.

The coloring agent used is as follows.

Example 1 Compound Example 2 of Specific Example (3) Compound Example 3 of Specific Example (4) Compound Example 4 of Specific Example (7) Compound of Specific Example (10) and 3,3-bis(1-n -octyl-2-methylindol-3-yl)phthalide 3
/1 (weight ratio) mixture (Example 5) 20 g of the compound of specific example (1), 20 g of zinc 4-β-p-methoxyphenoxysalicylate, which is an electron-accepting compound
, 20g of stearamide, a thermofusible substance, was added to 10
0g of 5% polyvinyl alcohol (Clari PVA105
) It was dispersed with an aqueous solution in a ball mill overnight to give a volume average particle size of 3μ. On the other hand, calcined kaolin (Anis
i 1 ax-93) was dispersed with a homogenizer together with 160 g of a 0.5% solution of sodium hexametaphosphate.

The dispersions dispersed as described above were mixed in a ratio of 5 g of the electron-donating colorless dye dispersion, log of the electron-accepting compound dispersion, 5 g of the stearamide dispersion, and 22 g of the calcined kaolin dispersion. emulsion 4
g and 5 g of a 2% aqueous solution of sodium (2-ethylhexyl)sulfosuccinate were added to obtain a coating liquid. This coating liquid was applied on high-quality paper with a basis weight of 50 g/m" in a dry coating amount of 6 g/m".
Coating was carried out using a wire bar so that the coating film had a thickness of m2, and a calendering process was performed to obtain a coated paper.

The coated paper is Fujitsu Limited High Speed Fax! JFF-20
When color was developed using 00, a magenta image was obtained. This image had high density and was excellent in light resistance and heat resistance before use and as an image.

Comparative Example Using 3.3-bis(1-n-ctyl-2-methylindol-3-yl)phthalide as a coloring agent, Example 1
An electron-donating colorless dye-containing microcapsule sheet was obtained in the same manner as above. 320001u on the sheet surface before use
When irradiated with x fluorescent lamp for 16 hours, significant yellowing of the skin was observed.

Claims (1)

[Claims] In a recording material that utilizes color development due to contact between an electron-donating colorless dye and an electron-accepting compound, the electron-donating colorless dye is an alkyl group or aryl group in which the 1-position of at least one indole has a substituted amino group. A recording material characterized by using a bisindolyl phthalide compound as a base.