JPH04187491A - Recording material - Google Patents

Abstract

PURPOSE:To obtain a recording material having a good color developing properties and an improved shelf stability by a method wherein in the recording material using an electron donative colorless dye and an electron accepting compound, a phenol derivative shown by a general formula (wherein, Ar is aryl group; X and Y are hydrogen atom, alkyl group, alkoxy group, or halogen atom, which may be the same or different; and X and Y may be bonded with each other to form a ring,) is used as the electron accepting compound. CONSTITUTION:As an electron accepting compound, bisphenol A, 2, 2-bis (3- methyl-4-hydroxyphenyl) propane, 2, 2-bis (4-hydroxyphenyl) heptane, and 3, 5-di-zinc octylsalicylate are exemplified. On the other hand, as an electron donative colorless dye, triphenylmethane phthalide compound, fluorane compound, phenothiazine compound, spiropyrane compound, fluorene compound, and other various compounds are exemplified. In addition, the ratio of the electron donative colorless dye and the electron accepting compound used is preferably 1:10-1;1 by weight. In this manner, the fading of an image part is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to recording materials, and more particularly to recording materials with improved storage stability.

(Prior art) Recording materials using electron-donating colorless dyes and electron-accepting compounds are pressure-sensitive paper, thermal paper, and light-sensitive pressure-sensitive paper.

It is already well known as electrically conductive thermal recording paper, thermal transfer paper, etc. For example, UK patent 2140449, US patent 44
80052, 4436920, Special Publication Showa 60-2399
2. JP-A-57-179836, JP-A No. 60-123556
, 60-123557 etc. for details.

As a recording material, research has been intensively conducted in recent years to improve the characteristics of (1) color density and (2) fastness of the color body and background.

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

(Object of the Invention) Therefore, an object of the present invention is to provide a recording material using a material that has good color development and improved storage stability.

(Structure of the Invention) The object of the present invention has been achieved by a recording material characterized in that a phenol derivative represented by the following general formula is used as the electron-accepting compound.

[In the above formula, Ar represents an aryl group, and X and Y may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom. Among the substituents represented by Ar in the above formula, an alkyl group.

An alkoxy group, a halogen atom, a phenyl group or a naphthyl group optionally substituted with a nitro group is preferable, x,
y is preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms;
Also preferred is one in which X and Y are linked to form an aromatic ring.

Specific examples of phenol derivatives according to the present invention are shown below, but the present invention is not limited thereto +1)N-(4-
hydroxyphenoxy) carbonylaniline (2) 4-methyl-N-(4-hydroquinophenoxy)
Carbonylaniline (3) 3-methyl-N-(4-hydroxyphenoxy)
Carbonylaniline (4) 2-methyl-N-(4-hydroxyphenoxy)
Carbonylaniline (5) 4-chloro-N-(4-hydroquinophenoxy)
Carbonylaniline (6) 3-chloro-N-(4-hydroquinphenoxy)
Carbonylaniline (7) 2-chloro-N-(4-hydroxyphenoxy)
Carbonylaniline (8) 4-nitro-N-(4-hydroquinophenoxy)
Carbonylaniline (9) N-(4-hydroxyphenoxy)carnenyl-
α-Naphthylamine α0IN-(3-hydroxyphenoquine)carbonylaniline 0114-Methyl-N-(3-hydroxyphenoxy)
Carbonylaniline a'24-chloro-N-(3-hydroxyphenoxy)
Carbonylaniline 03N-C2-methyl-3-hydroxyphenoxy) Carbonylaniline 041N-(4-methyl-3-hydroxyphenoxy)
Examples include carbonylaniline 05N-(4-chloro-3-hydroxyphenoxy)carbonylaniline Cl69N-(5-hydroxynaphthyloxy)carbonylaniline aη N-[7-hydroxynaphthyl(2)oxycarbonylaniline.

The electron-accepting compound used in the recording material of the present invention is conventionally known as an electron-accepting compound for recording materials. Phenol derivatives, salicylic acid derivatives, metal salts of aromatic carboxylic acids, acid clay.

Examples of these which may be used in combination with bentonite, novolac resins, metal-treated novolac resins, metal complexes, etc. No. 1973-51510,
JP-A-57-210886, JP-A-58-87089
No., JP-A-59'-11286, JP-A-60-176
Examples of electron-accepting compounds described in No. 795, JP-A No. 61-95988, etc. include bisphenol A, 2
．． 2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)hebutane, 1. l-bis(4-hydroxyphenyl)butane, 1,1-his(4-hydroxyphenyl)-2-ethylhexane.

1.1-bis(3-chloro-4-hydroxyphenyl)
-2-Ethylbutane, bis(3-hydroxyphenyl)sulfone, ■, 7-bis(4-hydroxyphenylthio)-3,5-dioxahebutane, (4-hydroxyphenyl)=(4- isopropoxyphenyl)
sulfone, 4-hydroquine benzoic acid ester,
2,4 dihydroxybenzoic acid-β-phenoxyethyl ester, 2,4 dihydroxybenzoic acid-α-methyl-β
-(3-methoxyphenoquine) ethyl ester, ■, 3
-bis(4-hydroxyphenyl)propane, 2-(
2,4-dihydroxyphenyl)-2-phenylpropane, 3,5-bis(α-methylhensyl)zinc salicylate, 3,5-his(α.

Zinc 3,5-bis(α,α-dimethylpencil)-6-methylsalicylate, zinc 3,5-di-t-octylsalicylate, etc.
Examples of the electron-donating colorless dyes according to the present invention include conventionally known triphenylmethane phthalide compounds, fluoran compounds, phenothiazine compounds, indolylphthalide compounds, leucoauramine compounds, rhodamine lactam compounds, Examples include various compounds such as triphenylmethane compounds, triazene 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. No. 3,491,111, U.S. Pat. No. 3,491,112, U.S. Pat.

Specific examples of fluorans are given in U.S. Patent Specification No. 3.624.
No. 107, No. 3,627,787, No. 3,641
, No. 011, No. 3,462.828, No. 3,68
No. 1,390, No. 3,920.510, No. 3,9
No. 59,571, specific examples of subirodibilanes are given in U.S. Patent No. 3,971.808, and pyridine and pyrazine compounds are given in U.S. Patent No. 3,775,424.
issue.

No. 3,853.869, No. 4,246,318, and specific examples of fluorene compounds are disclosed in Japanese Patent Application No. 61-2409.
When the recording material of the present invention described in US Pat. No. 89, etc. is used for pressure-sensitive paper, US Pat.
2,505°471, 2,505.489, 2,548.366, 2,712,507, 2
No. 730.456, No. 2,730,457, No. 3.
No. 103,404, No. 3,418,250, No. 4.0
It can take a variety of forms, as described in prior patents such as No. 10,038. Most commonly it consists of at least one pair of shifts 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.
457, a method using coacervation of a hydrophilic colloid sol described in British Patent Nos. 2,800,458, British Patent No. 867.797, British Patent No. 950,443, British Patent No. 98
Examples include the interfacial polymerization method described in US Pat. No. 9,264 and US Pat. No. 1.091.076, and the method described in US Pat.

When used for thermal paper, JP-A-62-144゜989
No. 62-244,883, etc. Specifically, the electron-donating colorless dye and the electron-accepting compound are 10μ or less in the dispersion medium,
The dispersion medium used is preferably pulverized and dispersed into particles having a particle size of 3μ or less.

Generally, an aqueous polymer solution having a concentration of about 0.5 to 10% is used, and dispersion is carried out using a hole mill, sand mill, horizontal sand mill, attritor, colloidal mill, etc.

The ratio of the electron-donating colorless dye to the electron-accepting compound used is preferably between 1:10 and 1.1, more preferably between 1:5 and 23, by weight.

In this case, a thermofusible substance may be included in the thermosensitive coloring layer in order to improve the thermal responsiveness. Representative thermofusible substances include aromatic ethers, thioethers, esters, and/or aliphatic amides or ureidos.

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. 63-15147'
No. 8, No. 63-235961, Japanese Patent Application No. 1-4447, No. 1-37070, etc.

These are used in finely dispersed form at the same time as the electron-donating colorless dye or simultaneously with the electron-accepting compound.The amount of these used is 20% or more and 300% or less of the weight of the electron-accepting compound. Additives may be added to the thus obtained coating liquid, which preferably has a content of 40% or more and 150% or less, as necessary, in order to meet various requirements. An example of an additive is an inorganic pigment in the binder to prevent staining of the recording head during recording.

An oil-absorbing substance such as a polyurea filler is dispersed, and fatty acids, metal soap, etc. are added to improve mold releasability from the head. Therefore, in general, in addition to electron-donating colorless dyes and electron-accepting compounds that directly contribute to color development, 1M thermofusible materials, waxes, antistatic agents, ultraviolet absorbers, antifoaming agents, conductive agents, and fluorescent materials are used. dye,
Additives such as surfactants are coated onto the support to form the recording material. Furthermore, a protective layer may be provided on the surface of the heat-sensitive recording layer, if necessary.

Usually, the electron-donating colorless dye and the electron-accepting compound are dispersed in a binder and applied. Water-soluble binders are commonly used, such as polyhinyl alcohol and human xynityl cellulose.

Hydroxypropylcellulose, epichlorohydrin-modified polyamide, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer.

Isobutylene-maleic anhydride copolymer.

Polyacrylic acid, polyacrylic acid amide, methylol-modified polyacrylamide starch derivatives.

Casein, gelatin, etc. are also added to these binders for the purpose of imparting water resistance.
Emulsions of hydrophobic polymers, specifically styrene-butadiene rubber latex.

Acrylic resin emulsion etc. can also be added.

The obtained heat-sensitive coating liquid is applied to high-quality paper, high-quality paper with a preliminary inspection layer, synthetic paper, plastic film, etc. At this time, the smoothness specified in JIS-8119 or 500 seconds or more, especially 800 seconds or more is applied. The use of a support is particularly preferable from the point of view of dot reproducibility (Examples of the invention) Examples are shown below.The present invention is not limited thereto.Unless otherwise specified in the examples, 1 weight %
represents.

Example-1 2-anilino-3-methyl-6-sibutylaminofluorane, which is an electron-donating colorless dye, N-(3-hydroxyphenoxy)carbonylaniline, which is an electron-accepting compound, and thermofusible The compound 4-ethoxyphenyl-4
20 g of each of the -chlorobenzyl ethers was dispersed in a ball mill overnight with 100 g of a 5% polyvinyl alcohol (Kuraray PVA105) aqueous solution to give a volume average particle size of 3 microns. On the other hand, calcined kaolin (Anisilex-9
3) 80g of 0°5% solution of sodium hexametaphosphate 1
It was dispersed together with 60 g using a homogenizer.

Disperse each dispersion as described above: 5 g of electron-donating colorless dye dispersion, 10 g of electron-accepting compound dispersion, 10 g of thermofusible compound dispersion, and 22 g of calcined kaolin dispersion.
4 g of a zinc stearate emulsion and 5 g of a 2% aqueous solution of sodium (2-ethylhexyl)sulfosuccinate were added to obtain a coating liquid. This coating liquid.

Dry coating weight is 6 g/m on high quality paper with basis weight of 50 g/m'.
m 2 was coated with a wire bar and calendered to obtain a printed paper.

When the coated paper obtained as described above was printed with a thermal head (KLT-216-811PD1) manufactured by Kyocera Corporation, a black image was obtained. This recorded image is 90RH%, 6
Example 2 Almost no discoloration of the image area was observed after being left at 0°C for 12 hours. -(3'-1=Droxyphenoxy)Carbonylaniline was changed,
Coated paper was obtained in the same manner as in Example-1. When printing was carried out in the same manner as in Example 1, a black image was obtained. When this image was left under moist heat conditions in the same manner as in Example-1, almost no discoloration of the image area was observed9. A cloth paper was obtained in the same manner as in Example 1, except that nylaniline was replaced with N-(4-hydroxyphenoxy)carbonylaniline. When printed in the same manner as in Example 1, a black image was obtained. or obtained. When this image was printed with a marker pen (manufactured by Zebra), almost no discoloration was observed in the 1 image area and the non-image area. , 2bis-(4-hydroxyphenyl)propane was used, but in the same manner as in Example 1, a coated paper was obtained. When printed in the same manner as in Example 1, a black image was obtained. When this image was written with a marker pen in the same manner as in Example 3, a black fog appeared in the non-image area.

Claims (1)

[Scope of Claims] A recording material using an electron-donating colorless dye and an electron-accepting compound, characterized in that a phenol derivative represented by the following general formula is used as the electron-accepting compound. . ▲There are mathematical formulas, chemical formulas, tables, etc.▼ In the above formula, Ar represents an aryl group, and X and Y may be the same or different and represent a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom. Moreover, X and Y may be connected to form a ring.