JPS6313778A - Recording material - Google Patents

Abstract

PURPOSE:To obtain a recording material having favorable stability of developed color images and fulfilling other requirements, by using crystal violet lactone and a p-substd. aminophenylindolylphthalide derivative as electron-donative colorless dyes. CONSTITUTION:Crystal violet lactone and a p-substd. aminophenylindolylphthalide derivative are used as colorless dyes. Among the p-substd. aminophenylinolylphthalide derivatives, a 4-substd. amino-2- alkoxyphenylindolylphthalide is preferred from the viewpoint of the hue of color formed. The ratio of the amounts of crystal violet lactone and the p- substd. aminophenylinolylphthalide derivative used is determined according to performance, the hue of color formed and economy, but the amount of the p-substd. aminophenylindolylphthalide derivative is preferably at least 10%, particularly, at least 30%. An electron-acceptive compound preferably has at least one phenolic hydroxyl group, and may be a salicylic acid derivative, a phenol derivative, a phenolic resin or the like. Among these compounds, a salicylic acid derivative is preferred from the viewpoints of color forming properties, the hue of color formed and light resistance of developed color images.

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 stability of colored images.

(Prior Art) Recording materials using an electron-donating colorless dye and an electron-accepting compound are already well known as pressure-sensitive paper, heat-sensitive paper, light-sensitive pressure-sensitive paper, electrically conductive heat-sensitive recording paper, and the like.

For example, British patent Ko/da0dadata, US patent Guku♂00
Yo2, the same Google 36920, 0-23.22-1 to Tokko Akira
Japanese Patent Application Publication No. 79.73, 60-723. ! j Otsu, same tO-723,! ! I am familiar with 7 etc.

The properties that a recording material should have are (1) sufficient color density and color density, (2) no capri, (3) sufficient fastness of the color body after color development, (
4) Appropriate color hue and suitability for copying machines, (5)
High S/N ratio, (6) sufficient off'F chemical properties of the color former, (easily soluble in organic solvents,
However, at present, nothing that completely satisfies these requirements has been obtained.

Particularly in recent years, with the diversification of requirements for recording systems, research has been intensively conducted to improve these characteristics. Among these, the demand for (3) is particularly strong for blue-coloring recording materials.

Conventionally, diphenylmethane compounds, triphenylmethane compounds, phthalide compounds, leucomethylene blue compounds, and the like have been known as compounds that develop a blue to blue-purple color. However, each of these compounds has its drawbacks.

For example, 3,3-bis(p-dimethylaminophenyl)
-B-Dimethylaminophthalide (i.e., crystal violet raftone) V1 develops quickly and exhibits a dark blue color, but
The lightfastness of the colored image is extremely poor. 3,2-bis(dimethylamino), a leucomethylene blue compound
-10-Benzoylphenothiazine (i.e., benzoyl leucomethylene blue) has a color image having extremely excellent light fastness, but has the disadvantage that color development is very slow and color development with an organic color developer is very poor. In addition, 3-(dardiethylamino-λ-ethoxyphenyl)-3-(/-ethyl-comethylindol-3-yl)-9 or 2-azaphthalide, which is known as a phenylindolyl azaphthalide compound, is encapsulated. It has the drawbacks of poor solubility in the solvents used and strong self-coloring properties.

The present inventors investigated the oil solubility, water solubility, partition coefficient, p K a , polarity of substituents, position of substituents, and crystallization when mixed with each of the electron-donating colorless dye and electron-accepting compound. We have pursued the development of good materials for recording materials and recording materials, focusing on characteristics such as changes in solubility.

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

(Structure of the Invention) The object of the present invention has been achieved by a recording material characterized in that crystal violet lactone and a pM-substituted aminophenylindolphthalide derivative are used as electron-donating colorless dyes.

Among the p-IR-converted aminophenylindolphthalide derivatives according to the present invention, those represented by the following general formula (1) are preferred.

R1 In the above formula, R and R' may be the same or different and represent an alkyl group, R1 and R2 may be the same or different and represent an alkyl group or an aryl group, and X is a hydrogen atom, an alkyl group, an alkoxy group, YSY' and Z represent an aryloxy group or a halogen atom, and YSY' and Z represent a hydrogen atom, an alkyl group, a rhodane atom, a substituted amine group or an alkoxy group.

In addition, the aryl group represents a phenyl group, a naphthyl group, or a heteroaromatic ring group, and these include an alkyl group, an alkoxy group, an aryloxy group, a rhodane atom, a nitro group,
It may have a substituent such as a cyan group, a substituted carbamoyl group, a substituted sulfamoyl group, a substituted amine group, a substituted oxycarbonyl group, or a substituted oxysulfonyl group. The alkyl group represents a saturated or unsaturated alkyl group or a cycloalkyl group, which may have a substituent such as an aryl group, an alkoxy group, an aryloxy group, a halogen atom, or a cyan group. .

Among the substituents represented by R or R' in the above formula, alkyl groups, alkoxyalkyl groups, halogen atom-substituted alkyl groups, and aryloxyalkyl groups having carbon atoms /~/Q are preferable, and the substituents represented by R1 an alkyl group having a carbon number of /~/, 2, an alkoxy group, an aryloxy group, or an alkyl group that may have a halogen atom as a substituent, and an alkyl group having 6 to 10 carbon atoms, alkoxy A phenyl group which may have a group or a halogen atom as a substituent is preferable, and among the substituents represented by lt2, an alkyl group with carbon atoms/~ and a phenyl group with 6 to 10 carbon atoms are preferable. Of the substituents represented by Among the substituents, hydrogen atoms, alkyl groups with a/~/2 carbon atoms, acyloxy groups, substituted amine groups, and alkoxy groups are preferred; among the substituents represented by Z, hydrogen atoms, alkyl groups with a/~/2 carbon atoms are preferred; and alkoxy groups are preferred.

Some examples of these include 3-(goodiethylamino-
J-(4t-diethylaminonyethoxyphenyl)-3-(/-inamyl-λ-methylindol-3-yl) phthalide,
3-(4t-diethylamine-2-ethoxyphenyl)
-, J -(/-β-ethoxyethyl-comethylindol-3-yl)7talido, 3-(<t-diethylaminonyethoxyphenyl)-3-(y-β-phenoxyethyl-comethylindole -3-yl)phthalide, J-(y-dibutylaminonicoethoxyphenyl)-3-(/-ethyl-nimethylindole-3-
yl) phthalide, 3-(4t-diethylamine-λ-ethoxyphenyl)-j-(7-ethyl-2-phenylindol-3-yl)phthalide, 3-(<t-N-cyclohexyl-N=ethylamino coethoxyphenyl)-3-(/-ethyl-2-methylindol-3-yl)phthalide, 3-(derN-ethyl-N-isoamylaminocoineamyloxyphenyl)-i-(/-
ethyl-2-methylindol-3-yl)phthalide,
3-(e-diethylamine-2-methylphenyl)-3
-(/-Ethylunimethylindol-3-yl)phthalide, 3-(y-N-cyclohexyl-N-ethylamino-2-ethoxyphenyl)-3-(i-ethylunimethylindol-3-yl)phthalide , 3-(gu N-butyl-N-ethylamino-2-methylphenyl)
-, J -(/-ethyl-,2-methylindol-3-yl)phthalide, 3-(q-diethylaminophenyl) -J -(/-ethyl-2-methylindole-
3-yl)phthalide, 3-(41-diethylamino2.
-ethoxyphenyl)-3-(/-hexyl-2-methylindol-3-yl)phthalide, 3-(u-diethylamino-ethoxyphenyl) -J -(/-octyl-nophenylindole-3- yl) phthalide, 3-(<1-diethylaminonyethoxyphenyl)-3-(/-ethyl-2-methylindol-3-yl)-yor-methoxyphthalide, 3-(\-ethyla Minochoethoxyphenyl)-3-(/-ethyl-nimethylindol-3-yl)-! or o-chlorophthalide, i-(diethylamine-niethoxyphenyl)-3-(/-ethyl-nomethylindol-3-yl)-yo or 6-chlorophthalide, and the like.

The usage ratio of crystal violet lactone and p-substituted aminophenylindolphthalide is determined by performance, color development, and economic efficiency, but it is preferable that the p-substituted aminophenylindolphthalide derivative accounts for 10% or more. In particular, it is preferable that the ratio be 30 or more.

Among the p-substituted aminophenylindolyl phthalide derivatives according to the present invention, p-substituted amine-nee alkoxyphenylindolphthalide is preferred from the viewpoint of its various color development properties.

The electron-accepting compound used in the recording material according to the present invention preferably has seven or more phenolic hydroxyl groups, and includes salicylic acid derivatives, phenol derivatives, phenol resins, and the like.

Among these, salicylic acid derivatives are preferred from the viewpoints of color development, various color phases, and light resistance of colored images. Some examples of phenol derivatives include guter jarifthylphenol,
9-phenylphenol, hydroxydiphenoxide, α-naphthol, β-naphthol, hexyluda
Hydroxybenzoate, 2,2'-dihydroxybiphenyl, 2,2-bis(terhydroxyphenyl)propane (bisphenol A), g, @'-inopylidene bis(nimethylphenol), /, /-bis-(3-
Chloroder-hydroxyphenyl)cyclohexane, /
, /-bis(3-chloro-q-hydroxyphenyl)-
2-ethylbutane, &, &'-Secondary isooctyldendiphenol, tert-octylphenol, da <1-sec-butylidenediphenol, 9-
p-methylphenylphenol, p,g'-isopentylidene diphenol,! ,! '-Methylcyclohexylitine diphenol, g, g'-dihydroquine diphenyl sulfide, /, 9-bis-(41/-hydroxycumyl)benzene, 7.3-bis-(ri'-hydroquinecumyl)benzene, g,p'-thiobis(1,-tert
-Daglu-3-methylphenol), y,e'-dihydroxydiphenylsulfone, hydroquinone monobenzyl ether, dihydroxypenzophenone, co, //
l-Dihydroxybenzophenone, polyvinylpenzyloxyphenol, 2,47. 'I'-trihydroxybenzophenone, 2.2", 4t, 4t'
-Tetrahydroxybenzophenone, dimethinope hydroxyphthalate, methyl hydroxybenzoate1.
2. , &'-trihydroxydiphenylsulfone, /
,! -Bis-p-hydroxyphenylpentane, /, O-bis-p-hydroxyphenoxyhexane, tolyl g-hydroxybenzoate, g-hydroxybenzoic acid α-phenyl pen/dyl ester, phenylprohynope g-hydroxybenzoate, phenethyl g-hydroxybenzoate ,
H-p-chlorobenzyl, p-methoxybenzyl g-hydroxybenzoate, benzyl co-hydroxybenzoic acid ester, Terhi'loki v benzyl?
iM m ly Chlorondyl ester, Kuhydroxybenzoic 2β-phenethyl ester, Kuhydroxy,! / , y /-dimethyl diphenyl sulfone, β-phenethyl orce' J Ne 1, cinnamyl oliseinate, orselic acid-0-chlorophenoxyethyl ester, 〇-ethylphenoxyethyl orselinate, 0-phenylphenoxyethyl orselinate , m-
phenylphenoxyethylorseline), U,! -dihydroxybenzoic acid-β-3'-t-butyl-Q'
-Hydroxyphenoxyethyl ester, /-t-butyluda-p-hydroxyphenylsulfonyloxybenzene, y-N-benzylsulfamoylphenol, co, siedihydroxybenzoic e-p-methylbenzyl ester, 2. Gauge hydroxybenzoic acid-β-phenoxyethyl ester,! , 4t-dihydroxy-6-methylbenzoic acid benzyl ester, methyl biscouhydroxyphenylacetate, ditolylthiourea, g,4t'-diacetyldiphenylthiourea, etc. Some examples of phenolic resins include p-substituted Examples include phenol formaldehyde resin, p-substituted phenol acetylene resin, and the like. As a salicylic acid derivative, the number of carbon atoms is 73.
The above mono- or di-substituted salicylic acid derivatives and metal salts thereof are particularly preferred. Substituents for salicylic acid derivatives include alkyl groups having 2 to 2 carbon atoms, aralkyl groups having 2 to 5 carbon atoms, alkoxy groups that may have substituents having 20 to 20 carbon atoms, and halogen atoms. . Some examples include 3-phenylsalicylic acid, 3-cyclohexylsalicyl tR13,3-di-tert-butylsalicyl fi
l, 3. ! -didodecylsalicylic acid, 3-methyl-yo-benzylsalicylic acid, 3-phenyl-! = (α, α−
dimethylbenzyl)salicylic acid, 3. ! -di(α-methylbenzyl)salicylic acid, 3. ! -dicyclohexylsalicylic acid, dadode/ruoxysalicylic acid, ku-octadecyloxysalicylic acid, gou-benzyloxysalicylic acid, ku-β-phenethyloxysalicylic acid, gu-β
-phenoxyethoxysalicylic acid, y, -(x-phenoyasibutoxy)salicylic acid D, 5-(p'-α'-methylbenzyl-p-α-methylbenzyl)salicylic acid, g-β-p-1lyloxyethoxysalicylic acid , tar β−
p-methoxyphenoxyethoxysalicylic acid, co-β-
Examples include p-butylphenoxyethoxysalicylic acid and metal salts thereof (eg, zinc salts, aluminum salts, calcium salts, etc.).

These may be used alone or in combination.

The recording material according to the present invention is made of a combination of a specific electron-donating colorless dye and an electron-accepting compound. It is particularly advantageous from the viewpoint of long-term preservation of records, as it hardly causes discoloration or fading even when exposed to light, heating, or humidification.

In the recording material according to the present invention, crystal violet lactone and p-substituted aminophenylindolphthalide are already well-known triphenylmethane phthalide-based compounds, fluoran-based compounds, phenothiazine-based compounds, indolyl aza-7thalide-based compounds, Recording materials can also be assembled using various compounds such as leucoauramine compounds, rhodamine lactam compounds, triphenylmethane compounds, triazene compounds, and spiropyran compounds.

In this case, it is preferable to use the colorless dye of the present invention in an amount of 6Q% or more from the viewpoint of improving properties.

When these colorless dyes and electron-accepting compounds are applied to recording materials, they are used in the form of fine dispersions or fine droplets.

When used with pressure sensitive paper, Vcf'i, U.S. Pat. ! θj
, 4/70 issue, same, 30! , 4t7/issue, same 2゜! θ! , Gudori-go, same co-! Da♂, No. 366, same, 7/2. ! No. 07, same, 7J' (17, Da! No. 6, No. 2,730, Da! No. 7, No. 3703 Da o4, No. 3,4t/♂, , 2/0, No. 010θ3 /
It takes various forms as described in prior patents such as No. Most commonly they consist of at least one pair of sheets containing separately an electron-donating colorless dye and an electron-accepting compound.

For methods of manufacturing capsules, see U.S. Pat.
Gu! No. 7, the same one? 0θ, g! ? A method using coacervation of a hydrophilic colloid sol described in No. 67.797, British Patent No. 67.797, same! 0. Guda No. 3, Guda No. 9?
ri, 7!6Q issue, same/.

Examples include the interfacial polymerization method described in US Pat. No. 09/, No. 076, and the method described in US Pat. As the capsule wall material, a synthetic resin wall material is preferable, and for example, a polyurethane and/or polyurea capsule is preferable.

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 and animal oils such as cotton oil and castor oil.

A coloring agent sheet is obtained by dissolving the coloring agent in mineral oil or a mixture thereof, incorporating it into microcapsules, and applying it to a support such as paper, high-quality paper, plastic sheet, or resin-coated paper. Neutral paper is particularly preferred as the support.

The combination of electron-donating colorless dyes of the present invention has good solubility in synthetic oils such as alkylated naphthalenes, alkylated diphenyls, and alkylcasiphenylalkanes, so it can be used in combination with low-solubility/ξ rough-in oils, etc. There are advantages that can be achieved.

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,
It is preferable to add an aniline antioxidant, a quinoline antioxidant, or the like.

Electron-accepting compounds, alone or in combination or with other electron-accepting compounds, include styrene-butadiene latex,
A color developer sheet is obtained by dispersing it in a binder such as polyvinyl alcohol and applying it to a support such as paper, plastic sheet, or resin-coated paper together with a pigment described below.

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 copying 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 in thermal paper, the electron-donating colorless dye and the electron-accepting compound are pulverized and dispersed in a dispersion medium to a particle size of 70 μm or less, preferably 3 μm or less. As a dispersion medium, generally 0. ! A water-soluble polymer aqueous solution having a concentration of about 1 to 10% is used, and dispersion is carried out using a ball mill, a sand mill, a horizontal sand mill, an attritor, a colloid mill, or the like.

The ratio of the electron-donating colorless dye to the electron-accepting compound used is preferably between / /θ and /, /, and more preferably /:! It is especially preferable to go between 3 and 3.
Nitrogen-containing organic compounds such as fatty acid amides, acetoacetanilide, diphenylamine, penzamide, carbazole, etc., as well as 2°3-di-m-)lylbutane, O-fluorobenzoyldurene, chlorobenzoylmesitylene, etc.

y'-dimethylbiphenyl, or carboxylic acid esters such as dimethyl isophthalate, diphenyl phthalate, dimethyl terephthalate, methacryloxybiphenyl, etc., or polyether compounds such as di-m
-) lyloxyethane, β-phenoxyethoxyanisole, /-phenoxy-2-p-ethylphenoxyethane, bis-β-(p-methoxyphenoxy)ethoxymethane, /-2'-methylphenoxy-2-''-ethyl Phenoxyethane, /-tolyloxy-chole-methylphenoxyethane, i,x-diphenoxyethane, /, terdiphenoxybutane, bis-β-(p-ethoxyphenoxy)ethyl ether, /-phenoxy-2-p-chlorophenoxy Ethane, /-2'-methylphenoxy-
2-4t"-ethyloxyphenoxyethane, /-@'
It is preferable to use a compound having a melting point of 2.0C to 730C, such as -methylphenoquine-2y//-fluorophenoxyethane. These are used in finely dispersed form at the same time as a colorless dye or at the same time as an electron-accepting compound.

In particular, it is preferable to disperse the colorless dye at the same time from the viewpoint of preventing fogging. These usage amounts are 1. ! It is added at a weight ratio of θ% or more and 300% or less, especially 0% or more/! It is preferably 0% or less.

Additives are further added to the coating liquid thus obtained in order 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 releasability from the head. For this purpose, fatty acids, metal soaps, etc. are added. Therefore, in addition to colorless dyes and electron-accepting compounds that directly contribute to color development, additives such as pigments, waxes, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, fluorescent dyes, and surfactants are used. is applied onto the support to constitute the recording material.

Specifically, pigments such as kaolin, calcined kaolin, talc, waxite, diatomaceous earth, calcium carbonate, aluminum hydroxide, magnesium hydroxide, calcined gypsum, silica, magnesium carbonate, titanium oxide, alumina, barium carbonate, and sulfuric acid are used as pigments. Barium, mica, microballoon, urea-formalin filler, one tickle of polyethylene,
Cellulose filler etc. particle size o, i or/! Selected from μ. Examples of waxes include ζ rough-in wax, Karpoki 7-modified paraffin wax, Kaunaba wax, microcrystalline wax, polyethylene wax, and higher fatty acid esters.

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

These are dispersed and applied in a binder.

Water-soluble binders are generally used, such as polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, epichlorohydrin-modified polyamide, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, and imbutylene-maleic anhydride. Examples include acid copolymers, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives, casein, and gelatin. In addition, in order to impart water resistance to these binders, water-resistant agents (gelling agents, cross-linking agents) are added, and emulsions of hydrophobic polymers, specifically styrene-butadiene rubber latex, acrylic resin emulsions, etc. etc. can also be added. The coating liquid is applied onto base paper, high-quality paper, synthetic paper, plastic sheet, or neutral paper in an amount of about 2 to 10 g/m2.

Furthermore, on the surface of the coating layer, a retention layer consisting of a water-soluble or water-dispersible polymer compound such as polyvinyl alcohol, hydroxyethyl starch, or epoxy-modified polyacrylamide and a crosslinking agent is provided to increase the resistance. It can also be improved.

When used for thermal paper, further OLS, 22. ! ♂! ♂
/ issue, 2/107! Various embodiments may be adopted, such as those described in Japanese Patent Publication No. 32-207 Gu. Alternatively, operations such as preheating, humidity control, or stretching of coated paper may be added prior to recording.

Electric thermal paper is, for example, JP-A-Sho Q? -//J'Gugu issue, same!
0-41793θ and the like. Generally, a coating liquid in which a conductive substance, a basic dye mainly composed of the fluoran derivative of the present invention, and an electron-accepting compound are dispersed together with a binder is applied to a support such as paper, or
The electrically conductive thermal paper of the present invention is produced by coating a support with a conductive material [2] to form a conductive layer, and then coating thereon with a coating liquid in which a colorless dye, an electron-accepting substance, 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, for example, by the method described in JP-A-37-/79♂3g. Generally silver iodobromide, silver bromide, silver behenate, Michler's ketone, benzoin derivatives,
A photopolymerization initiator such as a benzophenone conductor and a crosslinking agent such as a polyfunctional monomer such as a polyallyl, poly(meth)acrylate, or poly(meth)acrylamide are used together with a colorless dye and optionally a solvent to form polyether urethane,
A synthetic resin wall, such as polyurea, is encapsulated within the capsule. After imagewise exposure, the colorless dye in the unexposed area is brought into contact with a color developer to be colored.

The electron-donating colorless dye according to the present invention is synthesized by a known method. For example, the corresponding benzoyl benzoic acid and indole, or the corresponding carboquine benzoylindole and aniline derivative are combined in the presence of a condensing agent such as acetic anhydride or phosphorus oxychloride, and if necessary in the presence of a condensing agent such as chloroform, toluene or benzene chloride. Using volatile organic inert solvents! After reacting at a reaction temperature of θ~730°C for ~10 hours, the reactants were placed in ice water or cold dilute hydrochloric acid to hydrolyze the condensing agent, the above volatile organic inert solvent was added, and sodium hydroxide was added. Make alkaline with aqueous solution,
It is obtained by transferring the resulting dye into a solvent and distilling off the solvent under reduced pressure.

(Examples of the Invention) Examples will be shown below, but the present invention is not limited to these examples.

Examples/-I Preparation of color former sheet The electron-donating colorless dye shown in Table 1 was dissolved in 30 g of alkylated naphthalene. This solution is water with 3g of gelatin and gg of gum arabic dissolved in it! After adding it to θg with vigorous stirring and emulsifying it to form oil droplets with a diameter of /μ to 70μ,
Water 2! Added Og.

Acetic acid was added little by little to bring the pH to about 0 to cause coacervation, creating a wall of gelatin and gum arabic around the oil droplets, and formalin was added and the pH was raised to about 0 to harden the wall.

The thus obtained microcapsule dispersion was applied to paper and dried to obtain a color former sheet.

■ Preparation of color developer sheet Add 20g of the electron-accepting compound shown in Table 1! ChiSBR latex was dispersed in water-soluble tLs o o g [~, and 20 g of kaolin (Jossia kaolin) was further added and well dispersed to form a coating liquid. The obtained coating liquid was applied to paper and dried to obtain a color developer sheet.

When the thus prepared color forming agent sheet and color developing agent sheet were brought into contact with each other and pressure or impact was applied, a blue printed image was instantaneously obtained. The results of the light fastness test of this image are shown in Table 1.

Comparative Examples/~3 A color former sheet and a color developer sheet were obtained in the same manner as in Example/, except that the electron-donating colorless dye and electron-accepting compound in Example/ were changed to the compounds shown in Table 1. Color was developed and a light fastness test was conducted in the same manner as in Example. The results are shown in Table 1.

[Coloring body lightfastness test]

Irradiate the coloring body with 3.2,000 lux light for 70 hours,
The color density before and after irradiation was compared to determine the residual rate.

From the results in Table 1, it can be seen that the recording material of the present invention clearly has excellent light resistance.

Example! ■ Adjustment of color former sheet Partial sodium salt of polyvinylbenzenesulfonic acid (manufactured by National Starch, VER8A).

TLtoθ, average molecule ttoo, ooo) is approximately 10 parts
°C hot water! 1 part and dissolved while stirring. Approximately 3
After dissolving for θ minutes, cool. The pH of the aqueous solution was 2 to 3, and a 20% by weight aqueous solution of hydroxide was added thereto to bring the pH to 0.

On the other hand, diisopropyl naphthalate in which 0% crystal violet lactone and co,j% 3-(<t-diethylamino-coethoxyphenyl)-3-(/-octyl-j-methylindol-3-yl)phthalide were dissolved. 7,700 parts of a portion of the sodium salt of the polyvinylbenzenesulfonic acid! It was emulsified and dispersed in 700 parts of an aqueous solution to obtain an average diameter of Da.

! An emulsion was obtained with a particle size of μ. Separately, 6 parts of melamine, 37 parts of heavy formaldehyde aqueous solution, 3 parts of water
0 part was heated and stirred at 600C, and after 30 minutes, a transparent mixed aqueous solution of melamine, formaldehyde, and melamine-formaldehyde initial condensate was obtained. The pH of this mixed aqueous solution
Hag~? Met. Hereinafter, this mixed aqueous solution of melamine, formaldehyde, and melamine-formaldehyde initial condensate will be referred to as an initial condensate solution. The initial condensate solution obtained by the above method was added to and mixed with the above emulsion, and while stirring, the pH was adjusted to 6°0 with a 3.6% by weight hydrochloric acid solution, and the liquid temperature was raised to 6!0C. Stirring continued for several minutes. Cool this capsule liquid to room temperature and make 20 layers! The pH was adjusted to 9 and the temperature was adjusted with 1% sodium hydroxide.

To this capsule dispersion, 200 parts of a lOM aqueous polyvinyl alcohol solution and 50 parts of starch particles were added, and water was added to adjust the solid content concentration to 20 parts to prepare a color former-containing microcapsule coating liquid.

This coating liquid! A solid content of jg/m2 was coated on base paper of θg/m2 using an air knife coater and dried to obtain a color former-containing microcapsule sheet.

■ Preparation of color developer sheet 3! -Zinc di-α-methylbenzyl salicylate / 0
1 part was added to 20 parts of /-isopropylphenyl-cophenylethane and dissolved by heating at qo 0c.

This is 2 Tivolivinyl alcohol (PVA-2θj manufactured by Kuraray) water bath liquid! 0.7 part of 70% sodium sulfophosphate aqueous solution was added as a surfactant, and an emulsion was prepared using a homogenizer so that the average particle size of the emulsion was 3 μm.

Next, a dispersion of 20 parts of calcium carbonate, 20 parts of zinc oxide, 20 parts of sodium hexametaphosphate and 20 parts of water was prepared using a Keddy Mill, and after mixing the above emulsion,
As a binder, 10-chi PVA-/yo (manufactured by Kuraray)
700 parts of aqueous solution and carboxy-modified SBR latex (S
70 parts (as solid content) of N-3 oz., manufactured by Sumitomo Naugatux were added, and water was added so that the solid content concentration was 2 c% to obtain a coating liquid (A).

Next 3. ! -Zinc-di-alpha-methylbenzyl salicylate 7
0 parts, calcium carbonate, 20 parts, zinc oxide, 20 parts of sodium hexametaphosphate, and 200 parts of water were uniformly dispersed using a sand grinder so that the average particle size was 3 μm.

To the obtained dispersion, Ioo part of a 10% PVA-//θ (manufactured by Kuraray) aqueous solution and carboxy-modified SBR latex (SN
-3041 (manufactured by Sumitomo Naugatux) (as solid content) was added thereto, and water was added to adjust the solid content concentration to 20 g to obtain a coating liquid (B).

Coating liquid (A) and coating liquid (B) 3-! -A/B = sθ/! in terms of zinc α-methylbenzylsalicylate! 0
The mixture was mixed with sOg/m2 of base paper and coated with an air knife coater so that a solid content of J, Og/m2 was coated, and dried to obtain a color developer sheet.

When the color was developed in the same manner as in Example, a blue printed image was obtained. This image had high density and excellent light resistance and heat resistance.

Example: 70 parts of crystal violet lactone and 20 parts of 3-(cudiethylamino-coethoxyphenyl)-3-(/-ethyl-comethylindol-3-yl)phthalide
A dispersion liquid was prepared by mixing and grinding 1 part of a 70% polyvinyl alcohol aqueous solution of 1 JrO part and 7 parts of water using a ball mill for 72 hours. The particle size after crushing is approximately /,! It was a micron.

(Component A) On the other hand, 30 parts of goo β-(p-methoxyphenoxy)ethoxyzinc salicylate, 30 parts of cohenzyloxynaphthalene/jθ parts of /θ tivolivinyl alcohol aqueous solution,
and! ! A dispersion was prepared by mixing and pulverizing the mixture with water using a sand mill. The particle size of the insoluble material after pulverization was approximately 2 microns. (Component B) Next, 1 part of component A and 90 parts of component B were mixed, applied to paper, and dried to obtain thermal paper.

This thermal paper developed a blue color when heated with a heat source. The color image obtained was very stable against light, and even when the image was irradiated with an ultraviolet lamp for 7 hours, there was almost no change in either hue or density.

Claims (1)

[Claims] A recording material utilizing color development due to contact between an electron-donating colorless dye and an electron-accepting compound, characterized in that crystal violet lactone and a p-substituted aminophenylindolphthalide derivative are used as the colorless dye. material