JPS6114980A - Recording material - Google Patents

Abstract

PURPOSE:To provide a recording material excellent in a color forming property and the stability of a developed color image, constituted by containing a fluorane derivative respectively having an arylamino group, an aryl group and an amine residue at specific positions of the fruorane ring thereof and a phenol derivative. CONSTITUTION:A fluorane derivative (A) respectively having an arylamino group, an aryl group and an amine residue at the 2-, 3- and 6-positions of the fluorane group thereof {pref., 2-anilino-3-phenyl-6-diethylaminofluorane represented by formula [wherein R1 is an amine resdidue, R2 and R3 are aryl and R4 is H, Cl or (substituted) alkyl]}, a phenol derivative (B) (e.g., bisphenol A) and, pref. further, a heat-meltable agent (C) with a m.p. of 70-120 deg.C (e.g., stearlylamide) are contained to obtain an objective recording material.

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 that uses an electron-donating colorless dye and an electron-accepting compound that have improved color development and stability of a color-forming image. .

(Prior art) Recording material using an electron-donating colorless dye and an electron-accepting compound
It is disclosed in UITO et al. The minimum performance that such recording materials should have is (1) sufficient color density and color development sensitivity, (2) no fogging (color development phenomenon during storage before use), and (3) color development. The following requirements are that the color forming material has sufficient fastness, but currently no product has been obtained that completely satisfies these requirements.

Particularly in recent years, as recording systems have become faster, research on the above (1) has been intense. Regarding heat-sensitive recording materials, which are one type of recording material, the melting point of the electron-accepting compound itself may be adjusted to 1000C. However, it is difficult to control the melting point of phenolic compounds, which are currently the most widely used electron-accepting compounds, and the phenolic compounds themselves are expensive, making them impractical.

Other methods include the combined use of organic acids, phenolic compounds, and gold as electron-accepting substances, or the use of compounds with alcoholic hydroxyl groups as described in Japanese Patent Publication No. 9-77111 and Japanese Patent Publication No. 667. The use of polyvalent metal salts is described.

Ma7 to Tokko Sho J/-Kotatada! No. 1 describes the use of a copolymer of hydroxyethyl cellulose and maleic anhydride.

In addition, Japanese Patent Publication No. Shoj/-27j Tata and Japanese Patent Publication No. Sho1r-23/ disclose the addition of waxes.

It is also described that carboxylic acid esters such as dimethyl isophthalate, diphenyl phthalate, dimethyl terephthalate, etc. are added as sensitizers.

Also British Patent Publication λ.

070.33! No. A describes the addition of hindered phenols.

However, heat-sensitive recording materials produced using these methods are insufficient in color density and color sensitivity.

In addition, many methods for improving the stability of color images have been studied, including the following:
The addition of a phenol derivative of ert-butylphenol) was disclosed in Japanese Patent Application Publication No. 2003-110003. J-/73177 describes the addition of a water-insoluble modified phenol tree WI such as rosin modification, and JP-A-6-72 Tade No. 6 describes the addition of terephthalic acid ester.

However, all of the heat-sensitive recording materials produced using these methods have insufficient Ryotsu stability.

(Object of the Invention) Therefore, the object of the present invention is to provide a heat-sensitive recording material which has good color-forming properties and good stability of color-forming artists and satisfies other requirements.

(Structure of the Invention) The object of the present invention is achieved by a recording material containing t% of a fluoran derivative having a mono-amino group at the 2-position, an aryl group at the 3-position, and an amine residue at the 3-position. leather.

The present inventors have developed fluoran compounds having an arylamino group at the 2-position and various substituents at the 3-position. It was discovered that the fluorane ring having a methyl group in the position has a lower melting point, is highly oil-soluble, and is a colorless crystal that is difficult to caprilate, and has thus formed the basis of the present invention. In addition, the effect of the fluoran of the present invention is greatly exhibited especially when a heat-fusifying agent with a melting point of 0'C-/jO'c is used, and the color quickly develops to a pure black color and has good storage stability. I found out.

Among the fluoran derivatives according to the present invention, preferred ones are represented by the following general formula (1). (In the general formula below,
The 161 substituent positions on the fluorane ring are indicated by numbers. ) In the above formula, R1 represents an amine residue, R2+ and R3 each represent an alcoholic group, and %R4 represents a hydrogen atom, a chlorine atom, an alkyl group or an Fi-substituted alkyl group.

The sequence of amine residues represented by R1 includes an amino group,
Specific examples include groups having a total carbon number of 7 g or less, such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, amyl group, and isoamyl group. , hexyl group, cyclohexyl group, λ-ethylhexyl group, octyl group, benzyl group, sudearyl group, phenethyl group, phenyl group,
Amine residues substituted with one or two groups such as tolyl groups, secondary amine residues, such as dioctylamino, dibutylamino, N-ethyl-N-P-) 1) Ruamino, N-methyl -N-cyclohexylamino, pyridino, benzylamino, toluidino, p-ethyltoluidino, cyclohexylamino, dibutylamino, N-ethylisoamylamino, N-methylbutylamino, N-n
-hexylmethylamino% N-methylisoamylamino, N-ethyl β-phenethylamino, diethyl ryamino, and the like.

R2 represents phenyl, or a group substituted on /WALJ of a halogen atom, alkyl group, or alkoxy group.
A group selected from at: phenyl, chlorophenyl) +1 gives a fluorane that exhibits a black color upon contact with the phenol.

In the fluorane derivative according to the present invention, from 10°C to tro0
It is preferable to use one having a melting point of c, and an appropriate one can be selected according to the phenol derivative and heat-fusifying agent used.

The thermosensitive recording material containing the fluoran derivative according to the present invention has sufficient color density and color development sensitivity, and the developed dye is significantly more stable than the nine dyes produced from existing color formers, and can withstand long-term light irradiation. It is particularly advantageous in terms of long-term preservation of records, as it hardly causes any discoloration or fading even when heated or humidified. Fluorane derivatives also have excellent stability, and do not undergo deterioration or coloring even after long-term storage, and have near-ideal performance as color formers.

Representative examples of fluoran derivatives according to the present invention include the following compounds.

(1) 2-Ayu-11-3-pheny-6-dinithylaminofluorane (2) 2-di-nilino 3-phenyl-4-N-methylhexylaminofushiolane (3) -2-p-chloroanilino-3- Phenyl-A-
N-ethyl, isoamylaminofluorane (41,2-
72-noj-p-chlorophenyl-6-sibutylaminofluoran (5) 2-721) no-3-tolyl-AN-ethyl,
Hexylaminofluorane (6) λ-p-chloronilinoJ-) 11-dimethylaminofluorane (7) 2-anilino-3-dimethylphenyl-t-
N-Methyl, hexylaminofluorane (8) 2-anilino-3-phenyl-J-N-methyl, isoamylaminofluorane (9) 2-Ayusunote 3-to 11g-p-butylanilinofluoran Oran lj Among the phenol derivatives according to the present invention, preferred compounds are compounds having at least one phenolic hydroxyl group, more preferred are phenols in which either the co- or 5-position is unsubstituted, such as bis- (μm hydroxyphenyl) alkane derivative, bis-(3-chloro-μm hydroxyphenyl) alkane derivative, his-
(l-hydroxyphenyl) sulfone, (4cm hydroxyphenyl)-(styl'-alkoxyphenyl) sulfone m conductor, p-hydroxybenzoic acid ester derivative, resorcinic acid ester derivative, orceric acid ester derivative, gallic acid ester derivative, salicylic acid and These include alkyl or aralkyl substituted products thereof, zinc salts thereof, and the like.

List the following compounds in 12 as typical examples of phenol derivatives.

(1)+2. λ-bis(μm hydroxyphenyl)propane (2) l,l-bis(μm hydroxyphenyl)hexane (3)/,/-bis(3-chloro-μm hydroxyphenyl)cyclohexane+4)/l/-bis(- 3-Chloro-Hiro-hydroxyphenyl)-2-ethylbutane (5) Benzyl P-hydroxybenzoate (6) 3.
j-di-α-methylbenzylsalicylate zinc (7)”tμ′-dihydroxy-31-isopropyldiphenylsulfone (81/, /-his(μm hydroxyphenyl)cyclohexane (9) resorcinic acid cinnamyl ester 0 [β-7
Enethyl orselinate (11) Cinnamyl orselinate (a) β-〇-chlorophenoxy orselinate (13) β-phenoxyethyl resorcinate Q4) Resorcinic acid-0-methylbenzyl ester R9 Resorcinic acid co , ≠-dimethylphenoxyethyl ester (l[9β,β'-histohydroxyphenylthioethyl ether) Among these, phenolic compounds such as alkylene bisphenol and cycloalkylene bisphenol, and phenolic compounds with electron-withdrawing groups are particularly preferred. Useful.

Generally, acid clay, silica gel, calcined acid clay, etc. used in pressure-sensitive paper etc. provide a colored body upon contact with the fluoran, but the color tone thereof is not pure black.

The thermoplasticizer 2 is selected from compounds having functional groups such as ether, ester, and amide, and compounds having an aromatic ring.

Tatoba, stearic acid esteramide, stearic acid anilide, ethylene bisstearamide, benzoin, α-naphthol benzoate, β-naphthol p-methylbenzoate, meclat-t-butylphenol phenoxyacetate, para-phenylphenol p-chlorophenoxy acetate, ≠.

μ'-cyclohexylidene diphenol diacetate,
≠, 4t'-isopropylidene diphenol dimethyl ether, β-phenylethyl-p-phenylphenol needle, oxy/naphthoic acid phenyl ester, p-methoxycarbonylbenzoic acid ethylamide, stearyl urea phenyl ester, and the like.

Among these, ethers, esters, etc. having aromatic properties such as phenolic hydroxyl groups or derivatives of aromatic amines,
Amides and the like are preferred in the present invention.

(Synthesis 1) A typical method for synthesizing the fluoran derivative according to the present invention will be described.

(11j-Hydroxy-μ-converted amino-λ'-carpoxybenzophenone thoer))-by reacting with hydroxy- or alkoxy-cyal-11-lamine in the presence of an acetic acid medium.

+21 2-7mi/-3-711-ruJ-[converted aminofluorane and bromobenzene or iodobenzene are reacted in the presence of a copper catalyst.

As the acid catalyst in the above synthesis method +11, Lewis acids such as zinc chloride, aluminum chloride, magnesium chloride, calcium chloride, etc.; sulfuric acid, fuming sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, phosphoric acid, etc. Organic or inorganic acids are used.

In the synthesis method (2), the -monoaminofluorane derivative and the arylating agent are reacted in the presence of a catalyst, and the catalysts used in this synthesis method include copper powder, copper oxide, and iodide. Examples include copper compounds such as cupric iodide, nickel compounds, and cobalt compounds, and copper powder is particularly preferred. It is preferable to use all of these together with iodine, carbonate, magnesia, and potassium iodide.

Next, a specific example of synthesis of the fluoran derivative according to the present invention will be shown.

Regarding 3-aryl-μm aminophenol or anisole, which is a starting material, there are two methods: a method using reduction transfer gold of λ-arylnitrobenzene, a method of reacting with 3-arylphenol gold diazonium salt and then reducing it, ≠-
Various methods can be used, such as a method of reacting Nidroa=7-A[arylmagnesium halide. Also, 3-
A 3-aryl-guarylaminoanisole can also be obtained all at once by reacting an aryl μm halogen-substituted anisole with an acetamide of an aromatic amine.

(1) Synthesis of 2-phenyl-≠-methoxydiphenylamine When 3-phenyl-guaminophenol was added with 1-fold amount of acetic anhydride and stirred, 3-phenyl-a-acetaminophenol was produced.

Melting point: 14tt-♂QC0 When treated with dimethyl sulfuric acid in a caustic soda solution, 11 phenyl-methoxyacetanilide was obtained as crystals with melting point: //3-II0.

A 91001 flask with a stirrer and a cooling tube.
Phenyldermethoxyacetylamide 3.1g, /
+2 molar equivalents of iodobenzene, potassium carbonate λ, and 0.2ji of jg% copper powder were weighed out and stirred to form Ho'C-2.
Hold for 0 CKA time to obtain -1 phenyl-methoxy N-acetyldiphenylamine.

Then dipropylene glycol/jml, caustic potassium/,
Add Igf, hold for ia, r-it, r0cica time, heat, and then pour into ice water to precipitate crystals. λ-phenyl≠-methoxydiphenylamine having a melting point of 0C was obtained.

(b) Synthesis of λ-anilino-3-phenyl-A-diethylaminofluoran (Example ft+ compound) 0.0/j mol of the above-mentioned copheny-q-methoxydiphenylamine and 0.0/7 mol of 4-oxy-p-diethylaminobenzoylbenzoic acid. mol was condensed with concentrated sulfuric acid/jdi catalyst. The reaction product was collected by pouring it into water-cooled alkaline water. Developed with toluene-ethyl acetate using silica gel as a carrier. The solvent was distilled off, and recrystallization was performed with a mixed solvent of benzene-ether-hexane to isolate the desired fluoran as pure white crystals. The melting point was /22-joC.

f→ λ-anino-3-phenyl-4-N-methylisoamylaminofluorane (IFII (compound 81)
Synthesis ←) was carried out using the same operating sound λ-oxy+-N-methyl-isoamylaminobenzoylbenzoic acid.

After cooling with water for 2 hours and then standing overnight at room temperature, the mixture was poured into an aqueous solution of caustic soda to obtain a solid gold precipitate. After several tests, the mixture was developed with a hexane-ethyl acetate mixed solvent using silica gel as a carrier.

On evaporation of the solvent, dichloromethane crystals were obtained, which showed a deep black-purple color on TLC and a black color on contact with benzyl p-hydroxybenzoate.

Next, a general method for manufacturing the recording material according to the present invention will be described. When used as a heat-sensitive recording material, a binder is dissolved or dispersed in a solvent or dispersion medium, and a dye precursor containing the fluoran derivative of the present invention, a phenolic substance, and, if necessary, a thermofusible substance are added to the solution. The mixture is thoroughly ground and mixed, and inorganic pigments such as kaori, talc, and calcium carbonate are added to the radish to create a coating liquid. If necessary, add paraffin wax emulsion, latex binder, sensitivity improvement ~1, gold soap, antioxidant, hindered phenol, mirabilite, salt, sorbyl, etc.
! L regulators, antifoaming agents, ultraviolet absorbers, and the like can be added.

The liquid is applied to a support such as paper, plastic notebook, resin-coated paper, etc. and dried. When preparing the coating liquid,
You can mix all the ingredients at the same time and grind them, or you can make an appropriate combination, grind and disperse them separately, and then mix them.

Components 1 of each component constituting the heat-sensitive recording material include 1 to 2 parts by weight of a color patch precursor containing a fluoran derivative according to the present invention, 7 to 6 parts by weight of a phenol derivative, 0 to 30 parts by weight of a thermofusible substance, Pigment o, is parts by weight, binder l to /j parts by weight, and dispersion medium, 217 to 300 parts by weight.

As the dye precursor, one or more of the fluoran derivatives of the present invention may be used in combination, or a compound known as a coloring agent for thermal paper such as crystal violet lactone or a fluoran derivative may be mixed with the fluoran derivative of the present invention. It may also be used as Water is most desirable as the dispersion medium.

Next, examples of binders used in the present invention include styrene-butadiene copolymer, alkyd resin, acrylamide cobo-11mer, vinyl chloride-vinyl acetate copolymer, styrene-maleic anhydride cobo-11mer, synthetic rubber, and gum arabic. , polyvinyl alcohol, hydroxyethyl cellulose, and the like.

Especially in relation to the dispersion medium, water-soluble binders such as gum arabic, polyvinyl alcohol, hydroxymethyl cellulose, and carboxymethyl cellulose are desirable.

(Practical sequence of the invention) Practical sequence/λ-anino 3-phenyl-6-ethylaminofluorane 19! % polyvinyl alcohol aqueous solution ROML
was processed in a horizontal sand mill to obtain a dispersion with a particle size of Jμ.

On the other hand, bisphenol A109, β-naphthol benzyl ether iog, kaolin, 20fl and j% polyvinyl alcohol aqueous solution/001115 were treated in the same manner to obtain a dispersion with a particle size of /jμ. After thoroughly mixing these dispersions and adding dispersions of paraffin wax emulsion jO% dispersion 9j9 and stearic acid anisidide t9, the solids coating amount was 1 on a base paper of 30 g/m2.
It was applied at a concentration of g/m2 and dried.

Coated paper is heated by facsimile with energy of 31 mJ.
/cm". The degree of color development in the color development area was measured using a Matabes RD-type, and the color density was i and ir.

In addition, the obtained skin capsules (* indicate excellent stability, especially very stable against light) (even when irradiated with an INr ultraviolet lamp for 1 hour, there was almost no change in hue or density).

Example 1 Half of the fluorane derivative of Example 1 was added to 11,20,3
A recording paper was obtained in the same manner except that -chloro-6-dibutyl-minofluorane was used.

When the color is developed at 3 j mJ/cIIL2, the color develops quickly and in high concentration, and a thermal paper with extremely excellent stability of the color developed can be obtained.

Example 3 In place of the fluoran obtained in Example 3, phenylphenol benzyl ether was used in place of β-naphthol benzyl ether, and stearic acid amide was used in place of stearic acid. A heat-sensitive recording material was prepared using the same procedure. The color density is I! as in the practical row 1. ] 11, and it was 7.02.

Implementation sequence μ Implementation [In place of bisphenol A in HJ/, 1. A heat-sensitive recording material p4# was prepared in the same manner except that /-bis(≠-hydroxyphenyl)7chlorohexane was used. In this case as well, vivid coloring was provided.

Implementation queue! Implementation [HJ/'s β-naphthol benzyl ether and stearic acid anisidide were removed, but the same procedure was carried out.
A thermosensitive recording material was prepared. When the color was developed in the same manner as in Example 1, the degree of color development was Oo! Met.

Claims (1)

[Scope of Claims] 1) A recording material characterized by containing a fluoran derivative and a phenol derivative having an arylamino group at the 2-position, an aryl group at the 3-position, and an amine residue at the 6-position of the fluorane ring. 2) It is characterized by containing a fluoran derivative having an arylamino group at the 2-position, an aryl group at the 3-position, and an amine residue at the 6-position of the fluoran ring, a phenol derivative, and a heat-fusifying agent with a melting point of 70°C to 120°C. Recording materials.