JPS6317077A - Recording material - Google Patents

Abstract

PURPOSE:To obtain a recording material having an excellent stability of a color-formed image and meeting other conditions of qualification by employing p-substituted aminophenylindolylphthalide derivatives as a clear dye and a special organic acid as an electron receptive compound. CONSTITUTION:For this recording material, p-substituted aminophenylindolylphtalide derivative is employed as an electron donative clear dye and an organic acid having more than one phenylhydroxyl group as an electron receptive compound. Among the p-substituted aminophenylindolylphthalide derivatives, the one expressed by the genral formula (1) is preferable. In the mentioned formula, R and R' represent the alkyl group, although they may be the same or different, R1 and R2 the alkyl or aryl group, although they may be the same or different, X the hydrogen atom, alkyl group, alkoxy group, allyloxy group or halogen atom, Y, Y' and Z the hydrogen atom, alkyl group, halogen atom, substitutite amino group or alkoxy group.

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, the British patent xitito4t4t? , US Patent 4
t4t100!2, 4t'1j4920. Special Public Service 1977
−． 23, Ri2co, JP-A-77-/7? , ♂36, same 6
0-/koj,! It is detailed in 40-723.667 etc.

The properties that a recording material should have are (1) sufficient color density and color development sensitivity, (2) no capri, (3) sufficient fastness of the color body after color development, (
4) Appropriate color hue and suitability for copying machines, (5)
(6) The coloring material must have sufficient chemical resistance, (7) It must be easily soluble in organic solvents, etc., but currently there is no product that completely satisfies these requirements. Not yet.

Particularly in recent years, with the diversification of requirements for recording systems, research has been intensively conducted to improve these characteristics. Among these, requirements regarding (3) are particularly strong for blue color 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 drawbacks.

For example, 3,3-bis(p-dimethylaminophenyl)
-B-Dimethylaminophthalide (i.e., crystal violet lactone) develops quickly and exhibits a deep blue color, but the light resistance of the colored image is extremely poor. 3,7-bis(dimethylamino), a leucomethylene blue compound
-70-Benzoylphenothiazine (i.e., benzoyl leucomethylene blue) has a color image having extremely excellent light resistance, but has the disadvantage that color development is very slow and color development with an organic color developer is very poor. In addition, J-(4t-diethylamino-coethoxyphenyl)-3-(/-ethyl-comethylindol-3-yl)-4t or 7-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, pK'% polarity of substituents, position of substituents, and crystallinity 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 the characteristics of changes in solubility.

(Objective of the Invention) Therefore, an 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 is to use a p-substituted aminophenylindolphthalide derivative as an electron-donating colorless dye and an organic acid having at least one phenolic hydroxyl group as the electron-accepting compound. This was achieved through recording materials.

Among the p-substituted aminophenylindolyl phthalide derivatives according to the present invention, those represented by the following general formula (1) are preferred.

In the above formula, R and R' may be the same or different,
An alkyl group, R1 and R2 may be the same or different, and an alkyl group or an aryl group, X is a hydrogen atom,
Y, Y/ and 2 represent a hydrogen atom, an alkyl group, a halogen atom, a substituted amine group or an alkoxy group.

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 halogen atom, a nitro group, a cyano group, a substituted carbamoyl group, a substituted sulfamoyl group,
It may have a substituent such as a substituted amino group, a substituted oxycarbonyl group, or a substituted oxysulfonyl group. Further, 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 cyano 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 a carbon atom number of /~/θ are preferable, and among the substituents represented by R1, An aryl group, an alkoxy group, an aryloxy group, or an alkyl group having 6 to 10 carbon atoms as a substituent; an alkyl group, an alkoxy group, or a halogen atom having 6 to 10 carbon atoms; A phenyl group which may have as a substituent is preferable, and among the substituents represented by R2, the number of carbon atoms/~! An alkyl group having 6 to 10 carbon atoms and a phenyl group having 6 to 10 carbon atoms are preferable, and among the substituents represented by Atom and fluorine atom are preferable, and among the substituents represented by Y and Y', hydrogen atom, alkyl group having /~/2 carbon atoms, acyloxy group, substituted amino group and alkoxy group are preferable, and the substituent represented by z Of these, hydrogen atoms,
Preferred are alkyl groups and alkoxy groups having a carbon atom number of 1 to 2. When R2 is an alkyl group, R, R', Y,
The sum of the carbon numbers of R1 and R2 is 77 or more, or R1
, the sum of the carbon numbers of Y is Da or more, and when R2 is an aryl group, R1R', the sum of the carbon numbers of Y, R1, and R2 is 7
It is preferable that the number is 4 or more because the solubility of the color former in organic solvents increases.

Some examples of these include 3-(4t-diethylamino-λ-ethoxyphenyl)-, ? -(/-ethyl-methylindol-3-yl)phthalide, J-(g-
diethylamino-coethoxyphenyl)-i-(/-
Isoamyl-2-methylindol-3-yl)phthalide, 1-(4t-diethylamino-coethoxyphenyl)-3-(/-β-ethoxyethyl-2-methylindol-3-yl)phthalide, 3-(4t) -diethylamine--ethoxyphenyl)-j-(/-β-phenoxyethyl-comethylindol-3-yl)phthalide, 3-(4t-dibutylamino-coethoxyphenyl)-S-(/-niteruco Methylindole-3-
yl) phthalide, 3-(4t-diethylaminocoethoxyphenyl)-3-(/-ethyl-cophenylin)"-ni-3-yl)phI'!J)'1.?-
(4t-N-cyclohexyl-N-ethylamino-coethoxyphenyl)-3-(/-ethyl-comethylindol-3-yl)phthalide, 3-(4t-N-ethyl-N-isoamylamino-λ- isoamyloxyphenyl)-3-(/-ethyl-comethylindole-3
-yl)phthalide, J-(4t-diethylaminocomethylphenyl)-3-(/-ethyl-methylindol-3-yl)phthalide, 3-(4t-N-cyclohexyl-N-ethylaminocoethoxy) phenyl)
-S-(/-ethyl-2-methylindol-3-yl)phthalide, 3-(4t-N-butyl-N-ethylaminocomethylphenyl)-3-(/-ethyl-,2-
Methylindol-3-yl)phthalide, j-(+1-
diethylaminophenyl)-3-(/-ethyl-methylindol-3-yl)phthalide, 3-(4t-diethylaminoco-ethoxyphenyl)-j-(/-hexyleucomethylindol-3-yl)phthalide ,3
-(4t-diethylamino-coethoxyphenyl)
-j-(/-F/f-λ-phenylindole-3-
yl) phthalide, j-(4t-diethylaminocoethoxyphenyl)-3-(/-ethyl-methylindol-3-yl)-yo or 6-medoxyphthalide,
3-(4t-ethylamino-coethoxyphenyl)
-S-(/-dithyl-comethylindol-3-yl)-! or 6-chlorophthalide, 3-(4t-diethylamino-ethoxyphenyl)-3=(/-ethyl=
comethylindol-3-yl)-! Or 6-chlorophthalide, J-(2,4t-diethylaminophenol)-3(/-ethyl-cotathylindol-3-yl)phthalide, and the like.

Among the p-substituted aminophenylindolyl 7-thalide derivatives according to the present invention, da-substituted aminocoalkoxyphenylindolyl phthalide is preferred from the viewpoint of its various color development properties.

The electron-accepting compound used in the sickle material according to the present invention preferably has at least one phenolic hydroxyl group, such as salicylic acid derivatives, phenol derivatives, and phenol resins.

Among these, the combination with salicylic acid derivatives has color development and absorption peak! A range of 20 to ≦J0 nm is preferable from the viewpoint of various colored phases and light resistance of colored images. Some examples of phenol derivatives include goutajarifthylphenol, gouphenylphenol, gouphoxydiphenoxide, α-naphthol, β-naphthol, hexyl-gouphoxybenzoate, co, λ'-dihydroxybiphenyl, and co. , 2-bis(4t-hydroxyphenyl)pro/syn(bisphenol A), x, 4t'-isopylidenebis(2-methylphenol), /, /-bis(
3-chloro-hydroxyphenyl)cyclohexane, /,/-bis<3-chloro-hydroxyphenyl)-2-ethylbutane.

Da'-Secondary-isooctylidene diphenol, Tert-octylphenol, Dau 4t'-8ee
-butylidene diphenol, a-p-methylphenylphenol, 4t, &'-in-inchylidene diphenol, x,p'-methylcyclohexylidene diphenol,
g, 4t'-dihydroxydiphenyl sulfide, /
, 4t-bis-(4t/-hydroxycumyl)benzene, 7.3-bis-(9'-hydroxycumyl)benzene, g, 4t'-thiobis(d-tert-butyl-3-
methylphenol), g, 4t'-dihydroxydiphenylsulfone, hydroquinone monobenzyl ether,
-hydroxybenzophenone,
Methyl hydroxybenzoate, 2,41.41' -
) Lihydro-tetraoxydiphenyl sulfone, /, j-bis-p
-Hydroxyphenylpentane, /, two-bis-p-hydroxyphenoxyhexane, tolyl hydroxybenzoate, α-phenylbenzyl ester of hydroxybenzoate, phenylpropyl hydroxybenzoate,
phenethyl g-hydroxybenzoate, p-chlorobenzyl g-hydroxybenzoate, p-methoxybenzyl g-hydroxybenzoate, benzyl g-hydroxybenzoate, m-chlorobenzyl ter-hydroxybenzoate, β-hydroxybenzoic acid Phenethyl ester, goohydroxy-2/, 4t/-dimethyldiphenyl sulfone, β-7enethyl orselinate, cinnamyl orselinate, orserinic acid-〇-chlorophenoxyethyl ester, 0-ethylphenoxyethyl orselinate, 0-phenylphenoxyethyl orseline), m-phenylphenoxyethyl orseline), J,Q-dihydroxybenzoic acid-β-j'-
t-butyl-g'-hydroxyphenoxyethyl ester, /-t-butyl-g p-hydroxyphenylsulfonyloxybenzene, a-N-benzylsulfamoylphenol 1.2.4t-dihydroxybenzoic acid-p
-Methylbenzyl ester, 2,4t-dihydroxybenzoic acid-β-phenoxyethyl ester, co,terdihydroxy-bu-methylbenzoic acid benzyl ester, biscou-hydroxyphere methyl acetate, ditolylthiourea, a,4t'- diacetyldiphenylthiourea,
Some examples of diphenol resins include p-substituted phenol formaldehyde resin, p-substituted phenol acetylene resin, and the like. As salicylic acid derivatives, mono- or di-substituted salicylic acid derivatives having 73 or more carbon atoms and metal salts thereof are particularly preferred.

Examples of the substituent of the salicylic acid derivative include an alkoxy group having a carbon number of / to /co, a 7ralkyl group having a carbon number of 2 to 7, an optionally substituted alkoxy group having a carbon number of / to 20, a halogen atom, etc. There is. Some examples include 3-phenylsalicylic acid, 3-cyclohexylsalicylic acid, 3. ! −
tertiary butylsalicylic acid, 3. ! -di-dodecylsalicylic acid, 3-methyl-yo-benzylsalicylic acid,
3-Phenyru! -(α,α-dimethylbenzyl)salicylic acid, 3. ! -dibeα-methylbenzyl)salicylic acid, J,j-dicyclohexylsalicylic acid, datodecyloxysalicylic acid, kuoctadecyloxysalicylic acid, goubenzyloxysalicylic acid, guβ-phenethyloxysalicylic acid, kuβ-phenoxyethoxysalicylic acid, <1- (4 to monophenoxybutoxy) Salicyl 1
4--(1)'-α'-methylbenzyl-p-α-methylbenzyl) salicylic acid,! -α-methyluda'-phenylbenzylsalicylic acid, ter-β-p-tolyloxyethoxysalicylic acid, ku-β-p-methoxyphenoxyethoxysalicylic acid, gu-β-p-butylphenoxyethoxysalicylic acid, etc. and their metal salts (e.g., zinc salts) , aluminum salts, calcium salts, etc.).

These may be used alone or in combination.

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

In the recording material according to the present invention, p-substituted aminophenylindolyl azaphthalide can be a well-known triphenylmethane phthalide compound, a fluoran compound, a phenothiazine compound, an indolyl azaphthalide compound, 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 4OS 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.

For use with pressure sensitive paper, U.S. Patent No. 2. joj, 4
No. 170, same co, J-0! , 4t7/issue, same.

! θ! , Da? R number, same λ, 64tt, j4 number, same,
2/ko, No. 107, same, 730, 4t74, same No. 2,730, 4tj7, same 3/θ34t04,
Various forms can be used as described in prior patents such as No. 3, 4t/l, ZJ-0, and 4tO10θ3/. Most commonly they consist of at least one pair of sheets containing separately an electron-donating colorless dye and an electron-accepting compound.

A method of manufacturing capsules is described in a US patent.

roo, gt7, same, 2, 700, 413-/
The method using coacervation of a hydrophilic colloid sol described in No. 2, British Patent No. Otsu No. 2,797, same!
θ, 4t4tj issue, same t, 2 otsugu issue, same/.

Examples include the interfacial polymerization method described in U.S. Pat.

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 hetathalenes, alkylated diphenyls, alkylated diphenylmethanes, alkylated terphenyls,
Synthetic oils such as graphin (chlorinated); vegetable oils such as cotton oil and castor oil; animal oils; mineral oils, or mixtures thereof), and after containing it in microcapsules, it can be used in paper, high-quality paper, and plastic. A color former sheet is obtained by coating a support such as a 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 naphthalene, alkylated diphenyl, and alkylated diphenylalkane, so it can be used in combination with low-solubility oils such as No9 rough-in oils. There are advantages.

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, and uncut 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 have a particle size of 10 μm or less, preferably 3 μm or less, in the dispersion medium.
It is used after being crushed and dispersed to a particle size of μ or less. As a dispersion medium, generally 0. A water-soluble polymer aqueous solution with a concentration of about 1 to 10 cm is used, and dispersion is carried out using a ball mill, sand mill,
This is done using a horizontal sand mill, attritor, colloid mill, etc.

The ratio of the electron-donating colorless dye to the electron-accepting compound used is preferably between /:10 and /:/, and even /:! in terms of weight ratio. to 2:3 is particularly preferred. At that time, fatty acid amide, acetoacetanilide, diphenylamine,
Nitrogen-containing organic compounds such as penzamide, carbazole, etc. or λ.

+ carboxylic acids such as fullbutane, 0-fluoropenzoyldurene, chlorobenzoylmedicine, 7.41°Z'-dimethylbiphenyl, or dimethyl isophthalate, diphenyl phthalate, dimethyl terephthalate, methacryloxybiphenyl, etc. Ester or polyether compounds such as
-) lyloxyethane, β-phenoxyethoxyanisole, /-pheno-It-see-no p-ethylphenoxyethane, bis-β-(p-methoxyphenoxy)ethoxymethane, /-2'-methylphenoxy-λ-“- Etherphenoxyethane, /-tolyloxy-2-p-methylphenoxyethane, /,-1-diphenoxyethane,
/, 4t-diphenoxybutane, bis-β-(p-ethoxyphenoxy)ethyl ether, /-phenoxy-2
-p-chlorophenoxyethane, /-λ'-methylphenoxy J-1"-etheloxyphenoxyethane, /
It is preferable to use a compound having a melting point of 7.0C to 300C, such as -Q'-methylphenoxy-coater-fluorophenoxyethane.These are used in finely dispersed form at the same time as the colorless dye or at the same time as the electron-accepting compound.

In particular, it is preferable to disperse the colorless dye at the same time from the viewpoint of preventing capri. These amounts are added at a weight ratio of SOS to 300% relative to the electron-accepting compound, particularly 4tO% or more/! θ% or less is preferable.

Additives are added to the coating liquid obtained in this manner 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, polyethylene no.1-ticle,
Particle size of cellulose filler is 0. Selected from / or / jμ. Examples of waxes include paraffin wax, carboxy-modified paraffin wax, cownaparow 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.

Binders are generally water-soluble, such as polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl cellulose, epichlorohydrin-modified polyamide, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, and imbutylene-anhydride. Examples include maleic acid copolymers, polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide, starch derivatives, casein, and gelatin. In addition, water-resistant agents (gelling agents, cross-linking agents) are added to these binders for the purpose of imparting water resistance, and emulsions of hydrophobic polymers, specifically styrene-butadiene rubber latex, acrylic resin emulsions, etc. You can also add

Coating liquid can be used on base paper, high quality paper, synthetic paper, plastic sheet,
2-10 on polyethylene laminate paper or neutral paper
Approximately 2 g/rn is applied.

Furthermore, a protective layer of approximately 0.2 to 2 μm 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 on the surface of the coating layer to improve resistance. You can also do that.

When used for thermal paper, OLS, 222♂! ///
No. 2//(: #J-da, Tokkosho! Coco O/Cuco, etc.).Alternatively, prior to recording, preheating, humidity conditioning, stretching of coated paper, etc. You can also add operations.

For example, the electrically conductive thermal paper is published in Japanese Patent Publication No. 4T9-//J4T4.
same! It is manufactured by the method described in θ-4t/RI No. 30. In general, a coating liquid in which a conductive substance, a basic dye mainly containing 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 a conductive substance is coated on the support to conduct electricity. The electrically conductive thermal paper of the present invention is produced by forming a layer and applying thereon 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 and pressure sensitive paper is manufactured, for example, by the method described in Japanese Patent Application Laid-Open No. 77-77 No. 36. Generally silver iodobromide, silver bromide, silver behenate, Michler's ketone, benzoin derivatives,
A photopolymerization initiator such as a benzophenone derivative and a polyfunctional monomer such as a crosslinking agent such as a polyallylated compound, poly(meth)acrylate, or poly(meth)acrylamide are used together with a colorless dye and optionally a solvent to form a 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 benzoylbenzoic acid and indole, or the corresponding carboxybenzoylindole and aniline derivative are combined in the presence of a condensing agent such as acetic anhydride or phosphorus oxychloride, and if necessary, chloroform, toluene, bene/yne chloride, etc. After reacting at a reaction temperature of 30 to 730°C for 10 hours using a volatile organic inert solvent, the reaction product was placed in ice water or cold dilute hydrochloric acid to hydrolyze the condensing agent, Add an inert solvent and make alkaline with an aqueous sodium hydroxide solution.
It is obtained by transferring the resulting dye into a solvent and distilling off the solvent under reduced pressure.

, (Example) Examples are shown below, but the present invention is not limited only to these examples.

Examples/-G ■ Preparation of color former sheet 7 g of the electron-donating colorless dye shown in Table 1 was dissolved in 30 g of alkylated naphthalene. Add this solution to 6g of gelatin
Add 4 tg of gum arabic to 10 g of water with vigorous stirring to emulsify it to form oil droplets with a diameter of 7 μm to 70 μm, and then add 2 tg of gum arabic to 10 g of water. Added Og. Add acetic acid little by little to adjust the pH.
A gelatin and gum arabic wall was formed around the oil droplet, formalin was added, and the pH was raised to 9 to harden the wall.

The microcapsule dispersion obtained by applying this pressure was applied to paper and dried to obtain a coloring agent sheet.

■ Preparation of color developer sheet -0g of the electron-accepting compound shown in Table 1! The mixture was dispersed in 200 g of a polyvinyl alcohol aqueous solution, and 0 g of kaolin (Jossia kaolin) was added and well dispersed to prepare 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 ink was instantaneously obtained. Table 1 shows the results of the light fastness test for this image.

A color former sheet and a color developer sheet were obtained in the same manner as in Examples except that the electron-donating colorless dye and electron-accepting compound in Comparative Examples to Examples were replaced with the compounds shown in Table 1.

The color was developed and the light fastness test was conducted in the same manner as in Example. The results are shown in Table 1.

[Coloring body lightfastness test]

The colored body was irradiated with light of 3200 θ lux for 70 hours, and the color density before and after irradiation was compared to determine the residual rate.

The results in Table 1 show 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 Co., Ltd., VER8A, TLjoo, average molecular weight too, ooo > r part with hot water of about ♂θ0C?
! 1 part and dissolved while stirring. After dissolving for about 30 minutes, it is cooled. The pH of the aqueous solution is 2 to 3, and a 20% by weight aqueous sodium hydroxide solution is added to the solution to pH 4t.
o.

Separately, 100 parts of diisopropylnaphthalene in which 3.3 g of 3-(4t-jethylamino-coethoxyphenyl)-3-(/-octyl-λ-methylindol-3-yl)7thallide was dissolved was added to the polyvinylbenzenesulfonate. Some sodium salts of acids! The average diameter is obtained by emulsifying and dispersing in 100 parts of an aqueous solution.

! An emulsion was obtained with a particle size of μ. Separately, 6 parts of melamine, 37% by weight formaldehyde aqueous solution, 3 parts of water
0 part was heated and stirred with to0cVC to obtain a transparent mixed aqueous solution of melamine, formaldehyde and melamine-formaldehyde initial condensate having a diameter of 3°. p of this mixed aqueous solution
H was 6 to ♂. Hereinafter, this mixed aqueous solution of melamine, formaldehyde, and melamine-formaldehyde initial condensate will be referred to as an initial condensate solution. 3. Add and mix the initial condensate solution obtained by the above method to the above emulsion and stir. Adjust the pH to g with a wt% hydrochloric acid solution.

The temperature was adjusted to θ, the liquid temperature was raised to 6!0C, and stirring was continued for StO. This capsule liquid was cooled to room temperature, pHed with 20% by weight sodium hydroxide, and OVC adjusted.

200 parts of a 10% by weight polyvinyl alcohol aqueous solution and starch particles for this capsule dispersion! θ part was added and water was added to adjust the solid content concentration to θ to prepare a color former-containing microcapsule coating solution.

This coating solution was applied to a base paper of jig/m2 using an air knife coater so that the solid content was coated at jg/m2, and dried to obtain a color former-containing microcapsule sheet.

■ Preparation of color developer sheet 3, J-di α-methylbenzyl salicylate zinc / θ part / -isopropylphenyl - J-phenylethane λθ
The mixture was added to a portion and dissolved by heating at 0°C.

This was added to 10 parts of an aqueous solution of polyvinyl alcohol (PVA-20! manufactured by Kuraray), and 0.1 part of a 10% sodium sulfosuccinate aqueous solution was added as a rehabilitation surfactant, and the average particle size of the emulsion was adjusted using a homogenizer. An emulsion was prepared to have a thickness of 3μ.

Next, a dispersion was prepared using Keddy Mill using 0 parts of calcium carbonate, 20 parts of zinc oxide, 200 parts of sodium hexametaphosphate, and the above emulsion was mixed.
As a binder, IOO part of a 10% PVA-/10 (manufactured by Kuraray) aqueous solution and carboxy-modified SBR latex (
70 parts (as solid content) of SN-Jθ (privately manufactured by Sumitomo Naugatax) were added thereto, and the solid content concentration was adjusted by adding water to 20% to obtain a coating liquid (A).

Next Kj, j-di-alpha-methylbenzyl salicylate zinc/
Using part Q, 0 parts of calcium carbonate, 20 parts of zinc oxide, 200 parts of sodium hexametaphosphate and 200 parts of water, the particles were uniformly dispersed using a sand grinder so that the average particle size was 3 μm.

700 parts of an aqueous solution of /01PVA-/10 (manufactured by Kuraray) and 70 parts (as solid content) of carboxy-modified SBR latex (SN-304t, manufactured by Sumitomo Naugatax) were added to the obtained dispersion, and the solid content concentration was reduced to 0. Water was added to obtain a coating liquid (B).

Coating liquid (A) and coating liquid (B) are A/B=t in terms of zinc J-3-di-α-methylbenzylsalicylate.

Mix it with /jO,! S, O27m on base paper of θg/m2
The color developer sheet was coated using an air knife coater so that the solid content of No. 2 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.

Examples include 5-(4t-ethylaminoconitoxyphenyl)
-S-(/-ethyl-comethylindol-3-yl) phthalide (30 parts) was mixed with 160 parts of a 70% polyvinyl alcohol aqueous solution and 70 parts of water using a ball mill.
The mixture was mixed and pulverized for a period of time to prepare a dispersion. The particle size after crushing is approximately 7
．． It was 1 micron. (Component A) On the other hand, 30 parts of goo β-(p-methoxyphenoxy)ethoxyzinc salicylate, 30 parts of cobenzyloxynaphthalene/! A 10% polyvinyl alcohol aqueous solution in the θ part and water in the jJ part were mixed and ground using a sand mill to prepare a dispersion. The particle size of the insoluble material after pulverization was approximately 2 microns.

(Component B) Next, 1 part of component A and 4 tO parts of component B were mixed, coated on 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.

Patent Applicant: Fuji Photo Film Co., Ltd. Procedural Amendment October 2, 1986 Kinuta

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, a p-substituted aminophenylindolphthalide derivative is used as the colorless dye, and a phenolic hydroxyl group is used as the electron-accepting compound. Recording material characterized by using an organic acid having