JPS59133095A - Heat-sensitive recording paper - Google Patents

Abstract

PURPOSE:To enhance color developing property and stability of a developed color image, by using a specified anthryl ether derivative as a color development sensitivity enhancing agent, in a heat-sensitive recording paper comprising a colorless or light-colored color forming substance and a phenol compound. CONSTITUTION:A colorless or light-colored color forming substance such as a fluoran base dye, a phenol compound and at least one anthryl ether derivative of formula I or II (wherein each of R1 and R5 is an alkyl group, an alicyclic group, an aryl group or an aralkyl group; each of R2, R3 and R4 is a hydrogen atom, an alkyl group, an alicyclic group, an aryl group or an aralkyl group) are serarately dispersed respectively into media each of which contains a binder, the resultant three dispersed liquids are mixed with each other to obtain a mixture, to which a filler or the like is added, if required, and the resultant material is applied onto an appropriate base, followed by drying. The anthryl ether derivative is used in a quantity of 0.1-2pts.wt. per 1pt.wt. of the phenol compound.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to thermal recording paper [7], and particularly to thermal recording paper that has excellent color development and other recording suitability, and whose colored images are stable against fingerprints and the like.

(Prior art) Thermal recording paper that utilizes the heating coloring reaction of fluoran colorless dyes, phenols, and organic acids was published in Japanese Patent Publication No. 45-1403.
It was published in Publication No. 9, etc., and has been widely put into practical use. These thermal recording papers are used in a wide range of fields, including measurement recorders, computers and information communication terminals, facsimile machines, and automatic ticket vending machines. These recording devices are equipped with a thermal element such as a thermal head or a thermal pen, and when the element is heated, color is generated and a recording is obtained. Recently, with the diversification of uses and the improvement of the performance of devices, the quality required for thermal recording paper has become even more sophisticated. For example, with facsimiles, A4 size records can now be recorded in less than a minute, whereas previously it took several minutes. Under these circumstances, as a method to improve the sensitivity of thermal recording paper, for example waxes
No.), nitrogen-containing compounds (JP-A-49-34842),
It has been proposed to add 7-talic acid esters (Japanese Patent Application Laid-open No. 57-116690), but the color development sensitivity and
No paper has yet been obtained that satisfies the performance requirements of thermal recording paper in a well-balanced manner, such as stability of colored images, recording suitability, and background fog.

In heat-sensitive recording paper, a color-forming substance and a phenol compound are present in the heat-sensitive recording layer as finely dispersed particles, but when heated, one of the two components dissolves or the two components eutectic and become densely integrated with each other. It is thought that color develops on contact.

U.S. Pat. No. 1,509,375 lists one example of a suitable phenolic compound for use in this purpose: 2,2
-bis(4'-hydroxyphenyl)propane (B P
A, a compound with a melting point of 156°C) and is widely used today;
℃), it is difficult to develop vivid colors. For this reason, the compounds mentioned above are used as sensitivity enhancers in thermal recording paper, but these compounds have difficulty dissolving color-forming compounds and phenolic compounds, are sublimable, and require high thermal melting energy. It is very impractical.

(Object of the Invention) An object of the present invention is to provide a coloring sensitivity improving agent that is practical and can be used in a wide range of applications without having the above-mentioned drawbacks.

(Structure of the Invention) The present invention provides a heat-sensitive recording paper containing at least one colorless or light-colored color-forming substance and at least one phenol compound in the novel thermal layer, which is represented by the formula (I) of -g. expressed as an) IJ le ether visiting body or expression (UJ
At least one of the anthryl ether d represented by
This is a heat-sensitive recording paper characterized by containing seeds.

However, 几 and bird in the formula are groups selected from alkyl groups, cycloaliphatic groups, aryl groups and aralkyl groups, horse,
Island and melon may be the same or different and represent a hydrogen atom or a group selected from an argyl group, a cycloaliphatic group, an aryl group and an aralkyl group.

The configuration of the present invention will be explained in detail below.

(Color-forming substance) As the color-forming substance of the present invention, what is known as a fluoran dye that is usually colorless or light-colored can be used. Although not particularly limited, examples include the following.

6-diethylamino-6-methyl-fuanilitufluoran (black) 6-(N-ethyl-P-tolubuino)-6-methyl-
7-anilinofluorane (black) 6-diethylamino-
6-Methyl-7-(ortho,)ξlargemethylanilino)fluoran (black) 8-3-(N-inamyl-N-
ethyl)-6-methyl-7-anilinofluorane (black) 6-pyrrolidino-6-methyl-7-anilinofluorane (black) 6-bi is lysoino-6-methyl-7-anilinofluorane (black) 3-(N-cyclohexyl-N-methylamine)-6-
Methyl-7-anilinofluorane (black) 6-diethylamino-7-(orthochloroanilinolafluorane (
6-diethylamino-7-(meta-trifluoromethylanilino)fluorane (black) Ro-diethylamino-6-methyl-chlorofluorane (
(red) 6-diethylamino-6-methyl fluorane (red) 6-cyclohexylamino-6-chlorofluoran (orange) (Phenol compound) On the other hand, various phenol compounds can be selected depending on the use and required performance. However, the specific ItCu,2.
2-his(4'-hydroxyphenyl)propane (bisphenol A), 2,2-bis(4'-hydroxyphenyl)pentane, 2,2-bis(4'-hydroxy-5
', 5'-', ;chlorophenyl)-furopane,
1.1-bis(4'-hydroxyphenyl)cyclohexane, 2.2-bis(4'-hydroxyphenyl)hexane, 1.1-bis(4'-hydroxyphenyl)-
Propane, 1,1-bis(4'-hydroquinphenyl)butane, 2,6-di-tert-butylphenol, 2
teri-butyl-p-cresol, 2,5-di-tert-butyl-p-cresol, methyl p-hydroxybenzoate, p-hy);'o ethyl xybenzoate, benzyl p-hydroxybenzoate, p- Examples include, but are not limited to, tolylmethyl hydroxybenzoate, 7enyl p-hydroxybenzoate, and phenyl p-hydroxybenzoate.

For example, 0 parts by weight of these phenolic compounds.
．． 1 to 2 parts by weight of anthryl ether derivative are used.

(Anthryl ether derivative) Specific examples of the an)IJ ether derivative in the present invention include 1-yne amyloxy-anthracene, 1
-phenyloxy-anthracene, 1-tolyloxy-
anthracene, 1-benzyloxy-anthracene, 2
-benzyloxy-anthracene, 2.4-';:::
Trophenyl-anthracene, 1-naphthoxy-anthracene, 2-naphthoxy-anthracene, 1-benzyloxy-6-phenyl-anthracene, 2,7 J benzyloxy-anthracene, 2,7-diitzamyloxy-anthracene, etc. .

(Manufacturing method) The thermal recording paper of the present invention can be obtained by the following method. That is, a color-forming compound, a phenolic compound, and an anthryl ether derivative are separately ground and dispersed in a medium containing a binder at an appropriate concentration using a grinder such as a ball mill to particles with a diameter of several μm or less, The thus obtained dispersion was combined into 6 volumes to form a family, and fillers were added as needed.
A whitening agent, a wetting agent, a lubricant, an antifoaming agent, etc. are added, and the mixture is coated onto a suitable support and dried.

All of the fillers, brighteners, wetting agents, lubricants, antifoaming agents, and supports that can be used to produce conventional thermal recording papers can also be used in the present invention.

Conventional coating methods and drying methods can also be used as they are.

(Examples) In order to make the present invention easier to understand, preferred embodiments of the present invention will be described below, but the following examples are not intended to limit the invention.

Note that all "parts" in the examples are multilayer parts.

Example 1 Solution A (dye dispersion) -6-methyl-7-anilite fluorane 10% by weight aqueous polyvinyl alcohol solution 4 parts water
4 Part B Solution 2.2-bis(4'-hydroxyphenyl)propane
6 parts Zinc stearate 0
．． 5 parts stearic acid amide 0.5
Part 10 N amount% polyvinyl alcohol water bath liquid 18
Part C Liquid 1-benzyloxyanthracene 2 Part 1
0 weight polyvinyl alcohol aqueous solution 4 parts water
4
The five liquids of parts A and BXC are each ground and dispersed in separate ball mills to a particle size of 1 to 5 μm. Next, the dispersion liquid is mixed in the proportions shown below to prepare a coating liquid.

10 parts of solution A 20 parts of solution J3 10 parts of solution C 17 parts of calcium carbonate (50 weight water dispersion) Apply this coating solution to 50 f/t on one side of the base paper.
．． The sheet was coated and dried to a smoothness of 5R/A, and the sheet was then processed in a soot/calender to a smoothness of 500 to 500 seconds to obtain a heat-sensitive recording paper. The evaluation results are shown in Table 1 below.

Example 2 A thermosensitive recording paper was obtained in the same manner as in Example (1) using 2-penzyloxy-anthracene in Solution C of Example (1). The evaluation results are shown in Table-1.

Example 6 In the C solution of Example (1), 2,7-dibenzyloxy-
Using anthracene, a box scissors recording paper was obtained in the same manner as in Example (1). Table 1 shows the results of the evaluation of one song.

Comparative Example 1 Heat-sensitive recording paper was prepared at 7λ0 without adding liquid C of Example (1).
The evaluation results are shown in Table 1.

(1) Tokyo Shibaura Electric - Thermal facsimile Copix -
7,100 and measure the image density using a Macbeth densitometer D-
Measured at 104 (2) Image density residual rate after leaving the image for one day at 60°C (3) A. Image density after leaving the image for one day under the condition of 0°C - 90°C Survival Rate (Effect of the Invention) As an effect of the present invention, the following hR points are opened.

(1) Due to its excellent thermal response, it is possible to obtain high-density and clear one-shot records even at high speeds and Naochi J-ho records (4) (2) Competitive 74 Yaste No King against thermal heads, etc. There are no troubles, and the recording performance is extremely good.

(6) The background is white and does not become discolored over time.

(4) Colored images are less likely to fade due to fingerprints, humidity, or heat.

Applicant: Oji Seikai Co., Ltd. Agent: Patent Attorney Ii Kari Minoru

Claims (1)

[Scope of Claims] A heat-sensitive recording paper containing at least one colorless to light-colored color-forming substance and at least one phenol compound in the heat-sensitive layer; A thermosensitive recording paper characterized by containing at least one kind of tolyl ether derivative or anthryl ether derivative represented by formula (11). However, in the formula, R1 and l(, are groups selected from an alkyl group, a cycloaliphatic group, an aryl group, and an aralkyl group,
几2, R3 and melon are the same or different and represent a hydrogen atom or a group selected from an alkyl group, a cycloaliphatic group, an aryl group and an aralkyl group.