JPS58188842A - Color developing compound - Google Patents

Abstract

NEW MATERIAL:Pentamethylene bis-p-hydroxybenzoate of formula. USE:A color developing agent useful for the heat-sensitive color developing recording material such as heat-sensitive recording paper, electro thermo-recording paper, etc. It exhibits color developing property at a lower temperature than bisphenol A, etc., and is a white crystalline substance having a melting point of 130-131.5 deg.C. It is used in combination with a colorless or colored color-developing dye which develops its color with an electron acceptor. PROCESS:The compound of formula can be prepared, e.g. by reacting 1,5-pentanediol or 1,5-dihalogenopentane with p-hydroxybenzoic acid, its salt, its hydrochloride or its ester optionally in a solvent such as toluene under heat refluxing in the presence of p-toluenesulfonic acid, triethylamine, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new color developer used in recording materials that develop color in response to heat.

Color-forming dyes (hereinafter referred to as "color-forming dyes" that are colorless or light-colored themselves that develop color upon contact with heat-sensitive recording materials, especially electron-accepting substances)
Thermosensitive recording paper that uses a color-forming dye (called a color-forming dye) and an electron-accepting substance (developer) that develops the color has recently been widely used in facsimile machines, and as facsimiles become faster, heat-sensitive recording paper There is a strong demand for increasing temperature sensing ability as much as possible.

The present invention is intended to meet this demand, and bisphenol A (bis-p-hydroxyphenyl-dimethylmethane, hereinafter abbreviated as "BPA, H"), which has been conventionally used as a color developer for thermal recording paper. Or p-hydroxybenzoic acid benzyl ester (r, pHBB)
The purpose of the present invention is to provide a color developer that exhibits a color developing effect at a much lower temperature than those of the following.

According to the research of the present inventors, phtamethylene bis-p-
Hydroxybenzoate is a new material, and the present inventors have discovered that the temperature at which the chromogenic dye of this material develops color is significantly lower than that of BPA or TPPB. Furthermore, the present invention relates to a heat-sensitive color-forming recording material containing tamethylene bis to p-hydroxybenzoate as a color-forming dye.

Pentamethylene bis-p-hydroxybenzoate (hereinafter abbreviated as PMBHBJ) of the present invention is a combination of 1,5-bentanediol or 1,5-dihalogenopentane and p-
Melting point: 130, which can be synthesized by conventional methods using hydroxybenzoic acid, its salts, its acid chlorides, or its esters as raw materials
It is a white crystalline substance with a temperature of ~151.5°C.

Tables 1 to 4 show that PMBT (B) produces color-forming dyes at lower temperatures than BPA and PrTBB.
Shown in the table. The values in these tables are based on the color developed by heating both sides of the thermosensitive paper produced in Examples 1 and 2 at the temperature listed for 5 seconds using a dry heat tester (manufactured by Kishinori Gaku Kikai Co., Ltd.). Macbeth reflection densitometer RD-514
The higher the value, the darker the color.

First surface color-forming dye: 3-diethylamino-6-methyl-7-chlorofluoran Color tone dark red Color filter used: Lanten ◆58 BPA O, 120, 120, 160, 92
PHBB O,120,550,931,01
PMBHB [1,65υ, 82 1.01
1.03 Second surface coloring dye s3,6-bis(jethylua s) fluorane-〇-chlorophenyllactam Color tone: Purple pink Filter used: Lanthene ÷ 58 BPA O, 110, 120, 190, 47P
HBB O, 17a59 0.73 C
L75PMBHB O,601800,870,
90 Third surface coloring dye: 3-N-ethylcyclohexylamino-
6-Methyl-7-phenylaminofluorane Color tone: Black Filter used: Lanthane≠106 BPA O, 150, 250, 461, 17P
HBB O,621,051,131,22PM
BHB O, 881, 101, 221, 24th 4th
Surface color dye: 3-diethylamino-6-methyl-7-phenylaminofluoran Color development color v8: Black Filter used: Lanten ◆106 BPA IXL14 0.17 0.4
9 1.14PHBB O,581,121
, 201, 27PMBHB 1. OO1,16
1,221,28 These measured values indicate that PMBHB, which is the color developer in the present invention, is compared to BPA and PMBHB, which are conventionally used.
This shows that it exhibits color developing ability at a much lower temperature than HBB.

PMBHB has a remarkable low-temperature color development effect as mentioned above, and the color development dye produced by it is superior to BPA or PE (BB) in terms of light fastness and sweat fastness, and its color development is also stable in the dark. It is robust and shows no change even after being stored for 5 months.

As mentioned above, the PMBHB of the present invention is used as a color developer for heat-sensitive color-developing recording materials (for example, but not limited to heat-sensitive recording paper or electrically conductive heat-sensitive recording paper). The method of use thereof is the same as that of known color developers for heat-sensitive recording materials. That is, a heat-sensitive recording material is produced by dispersing fine particles of these color developers and fine particles of a color-forming dye in an aqueous solution of a water-soluble binder, and applying the suspension to paper or a suitable support and drying it. Can be done.

Examples of color-forming dyes include fluoran type, 7-thallide type,
Leuco type dyes such as lactam type, triphenylmethane type and spiropyran type can be used, but are not limited to these, and it goes without saying that these can be used in combination.

Examples of the water-soluble binder in the present invention include polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, styrene-maleic anhydride copolymer salt, styrene-butadiene emulsion, hinyl acetate-maleic anhydride emulsion, polyacrylate, polyacrylamide, Examples include, but are not limited to, starches, casein, gum arabic, and the like.

The above suspension may further contain dispersants (e.g. sodium dioctylsuccinate, sodium dodecylbenzenesulfonate, lauryl alcohol sulfate, IJium salts, fatty acid metal salts, etc.), sensitizers [e.g. bis(tertiary butyl phenol) ) type compounds], desensitizers (e.g. aliphatic higher alcohols, solid polyhydric alcohols, polyethylene,
glycols, guanidine derivatives, etc.), anti-blocking agents (e.g. stearic acid, zinc stearate, calcium stearate, carnauba wax, paraffin wax,
ester wax, etc.), fillers (e.g. clay, talc, kaolin, satin white, titanium oxide, calcium carbonate, magnesium carbonate, barium sulfate, magnesium silicate, aluminum silicate, etc.), antifoaming agents, polymer light stabilizers, fluorescence enhancers It can also contain whitening agents and the like.

The above suspension is not only used for heat-sensitive recording materials, but also for example in Japanese Patent Publication No. 51-16154 or Japanese Patent Publication No. 5
1-16155, an electrically conductive heat-sensitive recording material can be obtained by coating it on a conductive layer supported on a support and drying it.

Production Example 1 41.4f of p-hydroxybenzoic acid, 15.6f of 1,5-intanediol, and 2.8f of p-)luenesulfonic acid were added to 150ml of toluene, and heated with a water trap for 6 hours while stirring. Reflux was performed. The crystals precipitated upon cooling were washed with a 5% aqueous sodium bicarbonate solution and further washed with a toluene-acetone mixture to obtain 37.7 F white crystals of pentamethylene bis-p-hydroxybenzoate. Melting point: 130-131°C.

Production Example 2 For p-hydroxybenzoic acid 55.2 and 1,5-dibromo, methane 45.89 and triethylamine 40.51
The mixture was heated to a temperature of 120° C. for 6 hours with stirring. After cooling, 150% of acetone was added and heated under reflux to remove insoluble hydrobromide of triethylamine, and the p solution was treated with activated carbon and concentrated. The precipitate was thoroughly washed with hot chloroform and hot water and dried to obtain white crystals of intamethylene bis-p-hydroxybenzoate 4&8t.

Melting point: 150-131.5°C.

Usage example 1 is phtamethylene bis-p-hydroxybenzoate (P
MBHB) 10.5 t, 15 t aqueous solution of polyvinyl alcohol (Kuraray Co., Ltd., [Kuratu-1054) 4
1.5F, clay (Engelhard, rUw-90J
) a (+r and pure water 40. Of glass beads 10
02 into a 250+Rt polyethylene bottle, seal it, and attach it to a Red Devi intra-conditioner, shake it at a frequency of 630 times/min for 8 hours, remove the glass beads, and reduce the particle size to 1. An aqueous suspension of 3μ of PMBHB was obtained (liquid A) and 15% of 3-diethylamino-6-methyl-7-chlorofluorane &'5f, polyvinyl alcohol (same as above).
% aqueous solution 41.5 liters, clay (same as above) 15, (l
and pure water 40. (Pour No. 11 into a 250-mm polyethylene bottle with 100 f glass beads, seal it tightly, and shake with an intraconditioner at a frequency of 650 vibrations/min for 5 hours. After removing the glass beads, remove the fluoran compound. An aqueous suspension (particle size 2-3μ) was obtained (liquid B).

A coating solution was prepared by mixing 102 ml of each of liquid A and liquid B and stirring for 20 minutes.

Apply this coating liquid to white base paper with wire rod pigeon 12.
A thermosensitive recording paper was produced by coating the film using a 100% polyester resin and drying it with warm air at 60°C for 2 minutes.

This thermal recording paper was tested at 80°C, 90°C, 100°C and 120°C using a dry heat tester (Kishino Kagaku Kikai Products Co., Ltd.).
Both sides were heated for 5 seconds at m degrees Celsius to develop a color (vermilion). Macbeth reflection densitometer RD-514 measures the color density of the coloring surface.
The results measured using the mold are shown in Table 1.

Also, bisphenol A is used instead of PMBHB as a color developer.
Table 1 also shows the measured values of the colored surface of pressure-sensitive recording paper produced in the same manner using (BPA) and p-hydroxybenzoic acid benzyl ester (PHBB). - Usage example 2 5,6-bis(diethylamino)fluoran-〇-chlorophenyllactam 3-N-methylcyclohexylamino-6-methyl-7-7enylaminofluoran and 3-diethylamino-6-methyl- as color-forming dyes A thermal recording paper was produced in the same manner as in Example 1 using 7-phenylaminofluorane and PMBHB, BPA, and PHBB as color developers. These thermosensitive recording papers were colored in the same manner as in Example 1, and the values measured on the colored surface are shown in Tables 2, 3, and 4.

Procedural amendments June 18, 1982] 1 Director of the Patent Office Kazuo Wakasugi 1, Indication of the case Patent application No. 70293 of 1982 2°@t'11og* Color developer compound 3, person making amendment case Relationship with Patent Applicant Address: 3-60 Ukima, Kita-ku, Tokyo Name: Shin Nisso Kako Co., Ltd. 4, Agent 5, Amendment order with [” (voluntary) Page 5, line 10 from the bottom “3-N-ethyl” t”r3-
Correct as "N-methyl".

that's all

Claims (1)

[Scope of Claims] 1) Hung methylene bis-p-hydroxybenzoate 2) A colorless pale color dye that develops color with an electron-accepting substance is characterized by containing phtamethylene bis-p-hydroxybenzoate. A heat-sensitive color-developing recording material.