JPH0497883A - Recording material - Google Patents

Abstract

PURPOSE:To enhance the color forming properties, whiteness preservability and image preservability of a recording material by using a fluorane compound whose sixth position is substituted with a specific amino group 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, a fluorane compound whose sixth position is substituted with an amino group represented by formula (I) (wherein R1 is a hydrogen atom, an alkyl group or an aryl group, at least one of R2-R4 is an electron withdrawing group and the remainder is a hydrogen atom or a monovalent group or R2-R4 are mutually bonded to form a 5-12-membered ring containing an electron withdrawing group and X is a divalent group) is used as the electron donating leuco dye. By this method, the color forming properties, whiteness preservability and image preservability of the recording material are enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a recording material, and more particularly to a recording material with improved color development, blank paper storage stability, and image storage stability.

(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, current-carrying thermal recording paper, thermal transfer paper, and the like. For example, UK patent 2140449, US patent 4480052,
4436920, JP 60-23992, JP 5
7-179836, 60-123556, 60-1
I am familiar with 23557 etc.

As a recording material, in recent years (1) color density and color sensitivity (
2) Research is being carried out to improve the properties of color-forming bodies, such as their fastness.

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

(Object of the Invention) Accordingly, the object of the present invention is to provide a recording material using a material that has good color development, white color preservation property, and image preservation property, and also satisfies other necessary conditions.

(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 6th position is the following general formula (1). ) This was achieved by a recording material characterized by using a fluoran compound substituted with an amine group.

In the above formula, R1 represents a hydrogen atom, an alkyl group, an aryl group,
2-R4 is at least one electron-withdrawing group, the rest are hydrogen atoms or -valent groups, or R2-R1 is a 5- to 12-membered ring connected to each other and containing an electron-withdrawing group, and X is Represents a divalent group.

Specifically, R3 is a hydrogen atom, an alkyl group, an aryl group,
R2 has a halogen atom, a cyan group, a nitro group, an alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group which may have a substituent, an acyl group, an alkoxycarbonyl group, an aryloquinecarbonyl group, a substituent The optional carbamoyl group is R,, R, or R2, hydrogen atom, alkyl group, alkoxy group, aryl group, arylthio group, alkylthio group, arylthio group, NR,, R,5, NSO, R,,,NCOR,7
(R) 4 to R, 7 represent a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group), or R to R4 are connected to each other to form a 5- to 12-membered ring containing an electron-withdrawing group, X represents a group represented by general formula (11).

(L'), 1L'), -(R2). −(R3), =(R
4)ゎ-(R5>,-(L'),-(R7).

(II) In the above formula, L0, L'', L', L' are -0NH--N
HCO--CONH NH3O, -1-8O, NH--Co.

0CO--NHCONI(--0CONHNHCOO-
-CHoH--8 so--so, --co-, L', L'L5, L'
represents alkylene, aralkylene, arylene, a-h represents 0 or an integer of] (b-c2c]-e=0) (
(Connected to a carbon atom on the L” side).

In particular, the fluoran compound is preferably a compound represented by the following general formula (III).

In the above formula, R represents a hydrogen atom, an alkyl group, an aryl group,
2 is a halogen atom, a cyano group, a nitro group, So□R,.

,COR,,[R,,,R,, 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 hydrothermal group, NR, □R1, (R1□ and Rl'3 represent a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group),
R,, R, is a group represented by R2, hydrogen atom, alkyl group, alkoxy group, aryl group, aryloxy group, alkylthio group, arylthio group, NR1, R16, N5O
7R16, NCOR, - (R1, ~R1- represents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group), or R2-R4 are connected to each other to form a 5- to 12-membered compound containing an electron-withdrawing group. ring, R6 is a hydrogen atom, alkyl group, aryl group, alkoxy group, halogen atom, R1 is a hydrogen atom, alkyl group, aryl group, acyl group, R1-R6 is a hydrogen atom, alkyl group, aryl group, alkoxy group, aryloxy group, halogen atom, alkylthio group, arylthio group, substituted amino group, cyano group, nitro group, acyl group, acyloxy group, p - r is an integer from 1 to 5, and ring A is a heteroatom. X represents a group represented by the above general formula (II), which may include an aromatic ring.

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, a nitro group, a cyano group, a substituted carbamoyl group, a substituted sulfamoyl group, a substituted amino group, a substituted oxycarbonyl group, a substituted oxysulfonyl group, an alkylthio group, or an arylsulfonyl group.

More specifically, among the substituents represented by R1, ■4, -C
H,,-C,H,,-,YZ.

C, R2, OC, , H2IN , YZ, (n is an integer from 2 to 10, m is an integer from 1 to 5, Y and 2 are hydrogen atoms, alkyl groups, alkenyl groups, alkynyl groups, aryl groups, alkokyne groups , an aryloxy group, an alkylthio group, a halogen atom, a substituted amino group, a cyano group, a nitro group, an acyl group, a trihalomethyl group, a sulfamoyl group, and a heterocyclic residue).

Particularly preferred as R1 are a methyl group, an ethyl group, a propyl group, a butyl group, and the like.

In the above formula, the group represented by R5 is an alkyl group having 1 to 8 carbon atoms, an alkenyl group, an alkynyl group, an alkoxy group,
A halogen atom is preferred, particularly a methyl group, an ethyl group,
Preferred are methoxy group, hydrogen atom, methylthio group, and chlorine atom.

In the above formula, the group represented by R6 is a hydrogen atom, and has 1 to 1 carbon atoms.
The alkyl group of No. 8 is preferable, and a hydrogen atom, a methyl group, and an ethyl group are particularly preferable.

R7-R9 are hydrogen atoms, alkyl groups having 1 to 12 carbon atoms, alkoxy groups, acyl groups, and 6 to 12 carbon atoms;
An aryl group, an aryloxy group, or a halogen atom is preferable, and these may further have a substituent such as an alkyl group, a halogen atom, or an alkoxy group.

R2-R9 can be substituted with 1 to 5 on the benzene ring,
If there are more than one, they may be the same or different.

In the above formula, ring A is preferably a benzene ring, a naphthalene ring, a pyridine ring, a pyrimidazine ring, an indole ring, etc., and a benzene ring is particularly preferred.

When ring A is substituted with the same or different substituents,
As the substituent, an alkyl group, a norogen atom, a nitro group, a cyano group, an alkoxy group, etc. are preferable, and in particular,
Preferred are a chlorine atom, a fluorine atom, a methyl group, an ethyl group, a methoxy group, and an ethoxy group.

Among the groups represented by general formula (III), L', L'L5
, L7 represents linear or branched alkylene, aralkylene, or arylene, each preferably having 20 or less carbon atoms, particularly IO or less.

L', L', L', L' is -CH.

(CH, 廿, (CH2)3 (CHz).

-(CH2)5-゛ = (CH2)6- - (CH
2).

CH,’CH.

CH2-CH--CH, CH2CH CH.

C.F.

Examples include CF3, and these may further have substituents such as an alkyl group, an alkoxy group, and a halogen atom.

The substituent represented by R2- preferably has 12 or less carbon atoms.

1, l-diacetylmethyl group, l, 1-dicyanomethyl group, l-acetyl-1-benzoylmethyl group,
1,1-dimethoxycarbonylmethyl group, 1.1-jethoxycarbonylmethyl group, 1. 1 diphenyloxycarbonylmethyl group, l, 1-di-n-butoxycarbonylmethyl group, 1. 1-di-t-butoxycarbonylmethyl group, 1, 1 dibenzyloxycarbonylmethyl group, 1,1 dioctyloxycarbonylmethyl group, 1-acetyl-1-methoxycarbonylmethyl group, 1
-acetyl-1-ethoxycarbonylmethyl group, lacetyl-1-iso-propoquinecarbonylmethyl group, l
-Acetyl-1-butoxycarbonylmethyl group, 1-acetyl-1-hexyloquinecarbonylmethyl group, 1-
Acetyl-octyloxycarbonylmethyl group, ■-acetyl-1-pendyloquinecarbonylmethyl group, l-
Acetyl 1-phenoxycarbonylmethyl group, 1-propionyl-1-methoxycarbonylmethyl group, 1-acetyl-1-ethoxycarbonylethyl group, 1, 1-diacetylethyl group, 1-pivaloyl 1-methoxycarbonylmethyl group, 1- Cyano l-ethoxycarbonylmethyl group, l-benzoyl-1-ethoxycarbonylmethyl group, 1-acetyl-1-morpholinocarbonylmethyl group, 1-methoxycarbonyl-1-ethoxycarbonylmethyl group, l, l-diphenylsulfonylmethyl group, 1
-Tolylsulfonyl-1-benzoylmethyl group, 1.1
-(trifluoromethylcarbonyl)methyl group, 1.
l-dipivaloylmethyl group, l-furoyl-1-trifluoromethylcarbonylmethyl group, l-thienylcarbonyl-1-trifluoromethylcarbonylmethyl group, 1. l-Cicarbamoylmethyl group, ■-acetyl group 1
-phenylcarbamoylmethyl group, 1,1-dibenzoylmethyl group, ■, 1-dimethoxycarbonylethyl group,
1.1-jethoxycarbonylethyl group, 1. 1-diphenyloxycarbonylethyl group, 1. 1-diphenyloxycarbonylethyl group, 1. 1-di-n-butoxycarbonylethyl group, l,l-di-t-butoxycarbonylethyl group, l,1dibenzyloxycarbonylethyl group, l,1-simethoxycarbonyl-n-
Propyl group, 1゜1-dimethoxycarbonyl-n-butyl group, α.

α-dimethoxycarbonylbenzyl group, ■, l-dimethoxycarbonyl-1-methoxymethyl group, 1.1-jethoxycarbonyl-n-propyl group, 1.1-jethoxycarbonyl-1so-propyl group, 1.1- Jetoxycarbonyl-n-butyl group, 1,1-jethoxycarbonyl-1so-butyl group, 1. l-jethoxycarbonyl-tertbutyl group, α, α-jethoxycarbonylbenzyl group, β, β-jethoxycarbonyl phenethyl group, 1. l-jethoxycarbonyl-1-allylmethyl group, 1. ■-Jethoxycarbonyl-1-acetylaminomethyl group, 1,1-jethoxycarbonyl-1
-chloromethyl group, ■, 1-jethoxycarbonyl group 1
-cyclopentylmethyl group, 1.1-jethoxycarbonyl-1-phthalimidomethyl group, 1. l-jethoxycarbonyl-2=ethoxycarbonylethyl group, 1.
1. l.

Triethoxycarbonylmethyl group, benzoylmethyl group, 4-chlorobenzoylmethyl L4-=trobenzoylmethyl group, l-chloro-1-acetylmethyl group, 1-chloro-1-methoxycarbonylmethyl group, 1-bromo-
Examples include 1-benzoylmethyl group, nitromethyl group, and 1-nitroethyl group.

may be completed. The metal ion is preferably a divalent to tetravalent metal ion, such as zinc ion, calcium ion, iron ion, magnesium ion, nickel ion, aluminum ion, etc.

- When using the compound of formula (II) in thermal paper, the dispersed grain size of the crystals of the compound must be 2.0 μm in order to exhibit sufficient sensitivity.
The following is preferable, and 1.0 μ or less is particularly preferable.

When the compound of general formula (If) is used as a recording material, the melting point of the compound is 1.
The temperature is preferably 20°C or higher, particularly 130°C or higher.

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

Electron-donating colorless dyes according to the present invention include conventionally known triphenylmethane phthalide compounds, fluoran compounds, phenothiazine compounds, indolyl phthalide compounds, leuco auramine compounds, rhodamine lactam compounds, triphenyl It can be used in combination with various compounds such as methane compounds, triacene compounds, spiropyran compounds, and fluorene compounds.

Specific examples of phthalides are given in U.S. Reissue Patent Specification No. 23.0.
No. 24, U.S. Pat. Specification Tube No. 3゜624.107, No. 3.62
'7,787, same No. 3. ．． 641. No. 011, No. 3. 462. No. 828, same No. 3,681.39-0
No. 3,920.510, No. 3. -959.
Specific examples of spiropyrans are disclosed in U.S. Patent No. 3,971.808, and pyridine and pyrazine compounds are described in U.S. Pat. No. 4,246゜318, and specific examples of fluoran compounds are disclosed in Japanese Patent Application No. 61-240989.
It is stated in the number etc.

Examples of the electron-accepting compound used in the recording material of the present invention include phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids, acid clay, bentonite, novolac resins, metal-treated novolac resins, and metal complexes.

Examples of these are Special Publication No. 9309 of 1972 and Special Publication No. 1 of 1973.
No. 4039, JP-A-52-140483, JP-A-48
−． 51510, JP 57-210886, JP 58-87089, JP 59-11286, JP 60-176795, JP 61-95988, etc.

Examples of electron-accepting compounds include bisphenol A, 2
, 2-bis(3-methyl-4-hydroxyphenyl)propane, 2.2-bis(4-hydroxyphenyl)butane, 1.1-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)butane -hydroxyphenyl)-2-ethylhexane, 1, 1-bis(3-chloro-4-hydroxyphenyl)-2-ethylbutane, bis(3-allyl-4-hydroxyphenyl)sulfone, l, ? -bis(4-hydroxyphenylthio)-3,5-dioxahebutane, (4-hydroxyphenyl-(4-isopropoxyphenyl)sulfone), 4-hydroxybenzoic acid benzyl ester, 2,4 dihydroxybenzoic acid-β −
Phenoxyethyl ester, 2,4 dihydroxybenzoic acid-α-methyl-β-(3-methquinphenoxy)ethyl ester, 1,3-bis(4-hydroquinphenyl)
Propane, 2=(2,4dihydroquinphenyl)-2-
Examples include phenylpropane, 3,5-bis(α-methylbenzyl)zinc salicylate, and the like.

When the recording material of the present invention is used for thermal paper,
2-144,989, Japanese Patent Application No. 62-244.883, etc. Specifically, the electron-donating colorless dye and the electron-accepting compound are used after being pulverized and dispersed in a dispersion medium to a particle size of 10μ or less, preferably 3μ 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 11 by weight, and particularly preferably between 1:5 and 2.3.

At that time, a thermofusible substance can be included in the thermosensitive coloring layer in order to improve thermal responsiveness. Representative thermofusible substances include aromatic ethers, thioethers, esters, and/or aliphatic amides or ureides.

Examples of these are JP-A-58-57989 and JP-A-58-87.
No. 094, No. 61-58789, No. 62-10968
No. 1, No. 62-132674, No. 61151478, No. 63-235961, Japanese Patent Application No. 1-4447, No. 1-37070, etc.

Examples of thermofusible substances include phenethyl biphenyl ether, benzyloxynaphthalene, benzyl biphenyl, 1,2-diphenoxyethane, 1,2-m-tolyloxyethane, l-phenoxy-2-p-methoxyphenoxylene. ethane, 1-p-methoxyphenoquine-2-
〇-Chlorphenoxyethane, 1,2-di-p-fluorophenoxyethane, 1,3-di-p-methoxyphenoxypropane, 1,2-di-p-methoxyphenoquinepropane, l-phenoxy-2-p- Methoquinophenoxypropane, 1-p-methquinophenoxyethoxy-2-
p-methoxyphenoquinethane, 1,2-di-p-methquinphenylthioethane, p-methquinpensyluoquintolylmethane, (4methquinbenzyluoquin)-(3-
Examples include methyl-4chlorophenyl)methane and p-chlorohenzyloxy-p-ethoxyphenylmethane.

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 coating liquid thus obtained as necessary to meet various requirements. Examples of additives include dispersing oil-absorbing substances such as inorganic pigments and polyurea fillers in the binder in order 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. Further, a coating liquid similar to 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, hydroquinoethyl cellulose, hydroxypropyl cellulose, shrimp hydrin-modified polyamide, and ethylene-
Examples of suitable materials include maleic anhydride copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives, casein, and seratin. Further, for the purpose of imparting water resistance to these binders, a water-resisting agent may be added, or an emulsion of a hydrophobic polymer, specifically, a styrene-butashene rubber latte, a camphorax, an acrylic resin emulsion, etc. may be added.

The obtained heat-sensitive coating liquid is applied to high-quality paper, high-quality paper with an undercoat layer, synthetic paper, plastic film, etc. In this case, it is particularly preferable to use a support having a smoothness defined by JIS-8119 of 500 seconds or more, particularly 800 seconds or more, from the viewpoint of dot reproducibility.

When providing an undercoat layer mainly composed of pigments on a support, all general organic or inorganic pigments can be used, but in particular those with an oil absorption of 40 cc/100 g or more as specified in JIS-5101. Preferred examples include calcium carbonate, barium sulfate, titanium oxide, talc, waxite, kaolin, calcined kaolin, aluminum hydroxide, amorphous silica, urea-formalin resin powder, polyethylene resin powder, and the like.

When applying these pigments to a support, the amount of pigment is 2
g/rd or more, preferably 4g1rd or more.

Binders used in the undercoat layer include water-soluble polymers and water-insoluble binders, and the binders may be used alone or in combination of two or more.

Examples of water-soluble polymers include methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, starches, gelatin, gum arabic, casein, styrene-maleic anhydride copolymer hydrolyzate, ethylene-maleic anhydride copolymer hydrolyzate, and isobutylene. -Maleic anhydride copolymer hydrolyzate, polyvinyl alcohol,
Examples include carboxy-modified polyvinyl alcohol and polyacrylamide.

As the water-insoluble binder, synthetic rubber latex or synthetic resin emulsion is generally used, and examples include styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, methyl acrylate-butadiene rubber latex, and vinyl acetate emulsion. .

The amount of the binder used is 3 to 100% by weight, preferably 5 to 50% by weight, based on the pigment. Wax, anti-fading agent, surfactant, etc. may be added to the undercoat layer.

Pigments used as additives in the present invention include kaolin, calcined kaolin, talc, waxite, geysou 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, etc. Can be mentioned.

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

Further, in the present invention, it is preferable to use a wax having a melting point of 40 DEG to 120 DEG C. in view of head matching properties for facsimiles.

The wax has a melting point of 40 to 120°C, and includes paraffin wax, polyethylene wax, carnauba wax, microcrystalline wax, campria wax, montan wax, fatty acid amide wax, and the like. Among them, boraffin wax, microcrystalline wax, montan wax, and fatty acid amide wax are preferable, especially those having a melting point of 50 to 1
Paraffin wax, montan wax, and methylolsteramide at 00°C are preferred. The amount of wax used is
5 to 200% by weight of the electron-donating colorless dye, preferably
It is 20 to 150% by weight.

The hindered phenol compound is preferably a phenol derivative in which at least one of the 2nd and 6th positions is substituted with a branched alkyl group.

Examples of ultraviolet absorbers include cinnamic acid derivatives, benzophenone derivatives, benzotriazole phenol derivatives, etc. For example, α-noanoβ-phenylbutyl cinnamate, 0-benzotriazolylphenol, 0-benzotriazolyl-p-chlorophenol, 0-benzotriazolyl-2
, 4-di-t-butylphenol, and 0-hensitriazolyl 2,4-di-t-octylphenol.

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

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, ceratins, arahiacom, casein, styrene-maleic acid copolymer hydrolyzate, styrene -Maleic acid copolymer＼
- Water-soluble polymers such as feedster hydrolyzate, isobutylene-maleic anhydride copolymer hydrolyzate, polyacrylamide derivatives, polyvinylpyrrolidone, polystyrene sodium sulfonate, and sodium alginate, and styrene-phtadiene combination latex, acrylonitrile Water-insoluble polymers such as -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 a heat-sensitive 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, sulfosuccinic acid-based alkali metal salts, fluorine-containing surfactants, etc. are used. Specifically, the sea (
Sodium salts or ammonium salts such as n-hexyl)sulfosuccinic acid and cy(2-ethylhexyl)sulfosuccinic acid are preferred, or anionic surfactants are effective.

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,
3; No. 103,404, No. 3,418.250,
It can take various forms as described in prior patents such as No. 4,010,038. Most commonly they consist of a 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.
No. 457, a method utilizing coacervation of a hydrophilic colloid sol described in No. 2,800,458, and British Patent No. 867. No. 797, No. 950.443, No. 9
Examples include the interfacial polymerization method described in US Pat. No. 89,264 and US Pat.

In general, electron-donating colorless dyes are used alone or in combination in 1.
Dissolved in a vehicle (synthetic oils such as alkylated naphthalenes, alkylated diphenyls, alkylated diphenylmethanes, alkylated terphenyls, chlorinated paraffins, vegetable oils such as cotton oil, human oil, animal oils, mineral oils, or mixtures thereof), and is contained in microcapsules,
A color former sheet is obtained by coating paper, high-quality paper, plastic sheet, resin-coated chit paper, etc.

In addition, an electron-accepting compound and optionally additives, alone or in combination, are dispersed in a binder such as styrene-butadiene latex or polyvinyl alcohol, and are used together with pigments to support paper, plastic sheets, resin-coated paper, etc. Apply the developer sheet to your body by applying it to your body.

As a binder, use a combination of carboxy-modified styrene-butadiene latex and water-soluble polymer, light resistance,
Preferable from the viewpoint of water resistance. In addition, as a pigment, the average particle size is 5.
．． It is preferable from the viewpoint of color developing ability to use carnoum carbonate of Op or less in an amount of 60% by weight or more of the total pigment.

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.

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

Example-1 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., VER8A, Tl2O3) are dissolved in 95 parts of water. 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 4.5% of the compound of Specific Example (1) of the electron-donating colorless dye was dissolved was emulsified and dispersed in 100 parts of a 5% aqueous solution of a partial sodium salt of the polyvinylbenzenesulfonic acid. An emulsion with a particle size of 0μ 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. to obtain a transparent aqueous solution of melamine-formaldehyde initial polymer. This aqueous solution was mixed with the above emulsion. Adjust the pH to 6.0 with an aqueous phosphoric acid solution while stirring. 0 and raise the liquid temperature to 65℃ 6
Stirring was continued for an hour. 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 solution was coated on a 50 g/rrr base paper using an air knife coater so that the solid content was 5 g/m, and dried to obtain a capsule sheet containing an electron-donating colorless dye.

2) Preparation of electron-accepting compound sheet 3. Zinc 5-bis(α-methylpencyl)salicylate 1
A dispersion liquid consisting of 4 parts of calcium carbonate, 80 parts of calcium carbonate, 20 parts of zinc oxide, 1 part of sodium hexametaphosphate and 200 parts of water was dispersed using a sand glider so that the average particle size was 3 microns. To this dispersion were added 100 parts of a 10% PVA aqueous solution and 10 parts of carboxy-modified 513R latex (as solid content), and water was added so that the solid content concentration was 20% to obtain a coating liquid. This coating liquid was applied to a 50 g/rrf base paper using an air knife coater so that the solid content was 5.0 g/%, and dried to obtain an electron-accepting compound sheet.

The surface of the microcapsule sheet containing an electron-donating colorless dye is
When it was layered on an electron-accepting compound sheet and applied a load of 400 kg/ct to develop color, the developed color hue was deep black, indicating good storage stability.

Example-2 Compound of specific example (2) which is an electron-donating colorless dye, bisphenol A which is an electron-accepting compound, l-phenoxy-2-(4-methoxyphenoquine)propane which is a thermofusible compound 20 g of each was dispersed in a ball mill overnight with 100 g of 5% polyvinyl alcohol (Kuraray PVAl05) aqueous solution to give a volume average particle size of 3 μm. Meanwhile, calcined kaolin (8n1silex-93) 80 g
was dispersed with 160 g of a 0.5% solution of sodium hexametaphosphate using a homogenizer to give a dispersed particle size of 1.0 μm.

After dispersing as described above, each dispersion 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 diaryloxyalkane compound dispersion, and 22 g of a calcined kaolin dispersion. 4g emulsion of zinc acid and 2% (2-ethylhexyl)
A coating liquid was obtained by adding 5 g of an aqueous solution of sodium sulfosuccinate.

This coating solution was coated on a high-quality paper weighing 50 g/m using a wire bar so that the dry coating amount was 6 g/n, and calendering was performed to obtain a coated paper.

The coating solution obtained as described above was applied to a thermal printing experimental device equipped with a Kyocera ■ thermal head (KIT-216-8MPDI) and a pressure roll of 100 kg/crl just before the head at a head voltage of 24~'. Printing was performed with a pulse width of 1.0 while using a pressure roll under the conditions of a pulse cycle of 10 m5, and the print density was measured using a Maches reflection density system RD-918. The color density was 1.30.

In addition, the obtained colored images and unprinted areas have good storage stability.
Shows chemical resistance.

Example-3 A coated paper was obtained in the same manner as in Example-2 except that the compound of Specific Example (2) in Example-2 was replaced with the compound of Specific Example (3). When the color was developed in the same manner as in Example 2, the color density was 1.31. Furthermore, the colored images and unprinted areas obtained exhibited good performance in terms of storage stability and chemical resistance.

Example 4 A coated paper was obtained in the same manner as in Example 2, except that the compound of Specific Example (2) in Example 2 was replaced with the compound of Specific Example (7). When the color was developed in the same manner as in Example 2, the color density was 1.30. Moreover, the obtained colored image and unprinted area showed good storage stability and chemical resistance.

Comparative Example The compound of Specific Example (2) of Example-2 was converted into 2-anilino-
A coated paper was obtained in the same manner as in Example 2, except that 3.-methyl-6-N-diethylaminofluorane was used. When the color was developed in the same manner as in Example-2, the color density was 1.2.
It was 8. Further, the obtained colored image faded over time, and the unprinted areas showed background fog.

Claims (3)

[Claims] (1) In a recording material that utilizes color development due to contact between an electron-donating colorless dye and an electron-accepting compound, the 6th position of the electron-donating colorless dye is substituted with an amino group represented by the following general formula (I). A recording material characterized by using a fluoran compound ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ (I) In the above formula, R_1 represents a hydrogen atom, an alkyl group, an aryl group,
At least one of R_2 to R_4 is an electron-withdrawing group, and the rest are hydrogen atoms or monovalent groups, or R_2 to R_4 are 5- to 12-membered rings connected to each other and containing an electron-withdrawing group,
X represents a divalent group. (2) In the general formula (I), R_1 is a hydrogen atom, an alkyl group, or an aryl group, and R_2 is a halogen atom, a cyano group,
A nitro group, an alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group that may have a substituent, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group that may have a substituent,
A group in which R_3 and R_4 are represented by R_2, a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkylthio group, an arylthio group, NR_1_4R_
1_5, NSO_2R_1_6, NCOR_1_7 (
R_1_4, ~R_1_7 represent a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group), or R_2 to R_4
2. A recording material using the compound according to claim 1, wherein are connected to each other and represent a 5- to 12-membered ring containing an electron-withdrawing group, and X represents a group represented by the general formula (II). -(L^0)_a-(L^1)_b-(L^2)_c-
(L^3)_d-(L^4)_e-(L^5)_f-(
L^6)_g-(L^7)_h-(II) In the above formula, L^0, L^2, L^4, and L^6 are -O-, -N
H-, -NHCO-, -CONH-, -NHSO_2-, -SO_2NH-, -COO-, -
OCO-, -NHCONH-, -OCONH-, -NH
COO-, -CHOH-, -S-, -SO-, -SO_2-, -CO-, L^1, L^3
, L^5, L^7 are alkylene, aralkylene, arylene, and a to h are integers of 0 or 1 (however, b-c+d-e
=0) (connected to the carbon atom on the L^0 side). (3) A recording material characterized by using the compound according to claim 1, which forms a complex with a metal ion at the ▼ portion in the general formula (I) where there is a mathematical formula, chemical formula, table, etc.