JP2000326635A - Heat-sensitive coloring composition and heat-sensitive recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-sensitive recording material of superior coloring properties and storage properties, and a heat-sensitive coloring composition. SOLUTION: A heat-sensitive coloring composition is composed of a development compound, a coloring compound to be colored by reacting with the development compound under heating, and a polymer compound, all of which are dispersed in an organic solvent. The heat-sensitive coloring composition contains a 3-diethylamino-7-(m-trifluoromethylanilino)fluoran as the coloring compound and a bis(3-allyl-4-hydroxyphenyl)sulfone as the development component, and also contains one component selected out of a 4-benziloxy-4'-(2- methylglycidyloxy)diphenylsulfone, a 1,1,3-tris(2-methyl-4-hydroxy-5-1- cyclohexylphenyl)butane and a 1,1,3-tris(2-methyl-4-hydroxy-5-t-buthylphenyl) butane, and the heat-sensitive coloring composition is applied on a substrate and dried thereon to manufacture a heat-sensitive recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermosensitive coloring composition and a thermosensitive recording material. More specifically, the present invention relates to a thermosensitive coloring composition and a thermosensitive recording material of an organic solvent dispersion type having excellent coloring properties and preservability.

[0002]

2. Description of the Related Art In general, a thermosensitive recording material is prepared by separately dispersing a developer such as a leuco dye and a phenolic substance into fine particles, and then mixing the two with a binder, a sensitizer, and a filler. Agents, lubricants and other additives to make a coating liquid, paper,
It is applied to a film, synthetic paper, or the like, and obtains a color record by a chemical reaction that occurs when one or both of the leuco dye and the color developer melt and come into contact by heating. For color development of such a heat-sensitive recording sheet, a thermal printer or the like having a built-in thermal head is used. Compared to other recording methods, this thermal recording method is (1) no noise during recording, (2) there is no need for development and fixing, (3) maintenance-free, and (4) the machine is relatively Due to its low cost and other features, it is widely used in the facsimile field, computer output, printer fields such as calculators, recorder fields for medical measurements, automatic ticket vending machines, heat-sensitive recording labels, and the like.

[0003] Recently, the use of such features as application to vouchers such as commuter tickets and coupons, cards and the like has been expanding. The demand for heat-sensitive recording materials has also changed from one-time use (recording) to one that can withstand many uses, and the support for heat-sensitive recording materials has better surface uniformity than paper or the like. Use of plastic films and synthetic papers having good mechanical strength and water resistance has been increasing.

[0004]

Conventionally, a thermosensitive coloring composition (ink or paint, etc.) used for forming a thermosensitive coloring recording layer on a support made of paper is dispersed in water as a medium. The heat-sensitive recording material dispersion had good adhesion to paper, but had poor coating and printability and poor adhesion to plastic films and synthetic paper, etc., and was insufficient. Therefore, the use of a thermosensitive coloring composition using an organic solvent as a medium is considered, and although the coating property or printing property and adhesiveness are improved, the organic solvent used, a polymer compound as a binder, There are restrictions on the combination of heat-sensitive recording materials and the like, and there are dissatisfactions with the heat-sensitive recording characteristics, especially background fog and color sensitivity, as well as plasticizer resistance and oil resistance. The object of the present invention is as described above,
It is to solve the disadvantages of the prior art. That is, an object of the present invention is to provide an organic solvent-type thermosensitive coloring composition and a thermosensitive recording material for forming a thermosensitive coloring recording layer having less background fog, excellent coloring density and good storage stability.

[0005]

Means for Solving the Problems The present inventors have made various studies to achieve the above object, and as a result, completed the present invention. That is, the present invention relates to (1) a heat-sensitive color-forming composition obtained by dispersing a color-developing compound, a color-forming compound which reacts with the color-developing compound under heating, and a polymer compound in an organic solvent. 3-diethylamino-7- (m-trifluoromethylanilino) as the color-forming compound
Fluoran containing bis (3-allyl-4-hydroxyphenyl) sulfone as the color developing compound;
-Benzyloxy-4 '-(2-methylglycidyloxy) diphenylsulfone, 1,1,3-tris (2-methyl-4-hydroxy-5-t-cyclohexylphenyl) butane, 1,1,3-tris ( A heat-sensitive color-forming composition comprising one selected from 2-methyl-4-hydroxy-5-t-butylphenyl) butane. (2) the thermosensitive coloring composition of (1), wherein the organic solvent is a hydrocarbon-based organic solvent; (3) the thermosensitive coloring composition of (2), wherein the hydrocarbon-based organic solvent is liquid at ordinary temperature;
(4) The thermosensitive coloring composition according to (3), wherein the hydrocarbon-based organic solvent which is liquid at normal temperature is an aromatic hydrocarbon, a naphthenic hydrocarbon, or a paraffin-based hydrocarbon; (5) (1) to (4) The present invention also relates to a thermosensitive recording material obtained by applying a layer of the thermosensitive color-forming composition according to any one of the above to a support and drying it.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-sensitive color-forming composition of the present invention comprises the above-mentioned color-forming compound, namely, 3-diethylamino-7- (m-trifluoromethylanilino) fluoran, in an organic solvent, A coloring compound, that is, bis (3-allyl-4-hydroxyphenyl) sulfone, was further added to 4
-Benzyloxy-4 '-(2-methylglycidyloxy) diphenylsulfone, 1,1,3-tris (2-methyl-4-hydroxy-5-t-cyclohexylphenyl) butane and 1,1,3-tris ( 2-methyl-4-
(Hydroxy-5-t-butylphenyl) butane and a polymer compound.

The proportion of each component used in the present invention is such that 1 part by weight of the color-forming compound is 1 part by weight of the color-developing compound.
10 to 10 parts by weight, preferably about 1 to 5 parts by weight. Further, 4-benzyloxy-4 ′-(2-methylglycidyloxy) diphenylsulfone and 1,1,3-tris (2-methyl-4) were added to 1 part by weight of the above-mentioned coloring compound.
-Hydroxy-5-t-cyclohexylphenyl) butane and one selected from 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane are 0.5 to 5% by weight. Parts, preferably 0.5 to 3 parts by weight are suitable.

The proportion of each component used in the thermosensitive coloring composition of the present invention is such that the total amount of the above-described coloring compound and the developing compound is the total solid content (organic content) of the thermosensitive coloring composition. 20 to 89% by weight, and preferably about 30 to 70% by weight, based on the total amount of the components excluding the solvent. Also, 4-benzyloxy-4 ′-(2-methylglycidyloxy) diphenylsulfone, 1,1,3-tris (2-methyl-4
-Hydroxy-5-t-cyclohexylphenyl) butane and 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane are selected from thermosensitive coloring compositions. 10 to 79% by weight, preferably 20 to 6% by weight in the total solid content (components excluding the organic solvent)
0% by weight and the amount of the polymer compound is 1 to 70% by weight, preferably about 10 to 40% by weight. In addition, if necessary, additives and the like may be respectively contained in arbitrary ratios, for example, 0 to 30% by weight. In addition, 3-diethylamino-7- (m-trifluoromethylanilino) fluoran is obtained from CAS N
o. No. 68134-61-2 is a known compound registered in Chemical Abstract.

The organic solvent used in the present invention includes, for example, hydrocarbon solvents such as aromatic hydrocarbons, naphthenic hydrocarbons and paraffin hydrocarbons, and preferably hydrocarbon solvents which are liquid at room temperature. Examples of the aromatic hydrocarbon which is liquid at normal temperature include benzene, toluene, xylene, ethylbenzene, ethyltoluene and the like, and a mixture thereof. Among them, it is preferable to use toluene and / or xylene. Examples of naphthenic hydrocarbons that are liquid at room temperature include cyclopentane, methylcyclopentane,
1,1-dimethylcyclopentane, 1,3-dimethylcyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, 1,2,4-trimethylcyclohexane and the like, and mixtures thereof, among which cyclohexane and / or ethyl Preferably, cyclohexane is used. Examples of paraffinic hydrocarbons that are liquid at room temperature include n-hexane, n-heptane, and n-hexane.
Octane, n-nonane, or an isomer thereof, or a mixture thereof may be mentioned. These solvents may be used alone or as a mixture. The amount used is 50 to 1000% by weight, preferably 100 to 500% by weight, based on the total amount of solids.
% By weight.

The polymer compound is used as a binder, and a compound which is soluble in an organic solvent to be used and has a film-forming property is used. Specific examples thereof include, for example, polyvinyl chloride, polystyrene resin, acrylic resin, acrylic styrene copolymer, polyester resin, polycarbonate resin, polyurethane resin, polybutyral resin, epoxy resin, furan resin, vinyl toluene copolymer, rosin ester Resins. These polymer compounds are
1 to 70% by weight, preferably 1% by weight of the total solids in the composition
0 to 40% by weight is contained.

Other additives used as required include, for example, fillers, heat-fusible compounds (sensitizers) and the like. Usable fillers include, for example, calcium carbonate, magnesium carbonate, magnesium oxide, silica, white carbon, talc, clay, alumina, magnesium hydroxide, aluminum hydroxide, aluminum oxide, barium sulfate, polystyrene resin, acrylic resin, polyolefin Resins, benzoguanamine resins, melamine resins, urea-formalin resins and the like.

Examples of usable heat-fusible compounds include waxes such as animal and vegetable waxes and synthetic waxes, higher fatty acids, higher fatty acid amides, higher fatty acid anilides, and the like.
Acetylized aromatic amine, naphthalene derivative, aromatic ether, aromatic carboxylic acid derivative, aromatic sulfonic acid ester derivative, carbonic acid or oxalic acid diester derivative, biphenyl derivative, terphenyl derivative, etc. What has a melting point of can be used.

The waxes include, for example, wood wax, carnauba wax, shellac, paraffin, montan wax,
Paraffin oxide, polyethylene wax, polyethylene oxide and the like, as higher fatty acids, for example, stearic acid,
Examples of higher fatty acid amides such as behenic acid include stearic acid amide, oleic acid amide, N-methylstearic acid amide, erucic acid amide, methylolbehenic acid amide, methylolstearic acid amide, methylenebisstearic acid amide, and ethylenebisstearin Acid amides and the like, higher fatty acid anilides such as stearic acid anilide and linoleic acid anilide, acetylated aromatic amines such as acetotoluidide, and naphthalene derivatives such as 1-benzyloxynaphthalene, Benzyloxynaphthalene, 1-hydroxynaphthoic acid phenyl ester and the like include aromatic ethers such as 1,2-diphenoxyethane, 1,4
-Diphenoxybutane, 1,2-bis (3-methylphenoxy) ethane, 1,2-bis (4-methoxyphenoxy) ethane, 1,2-bis (3,4-dimethylphenyl) ethane, 1-phenoxy- 2- (4-chlorophenoxy) ethane, 1-phenoxy-2- (4-methoxyphenoxy) ethane and the like include aromatic carboxylic acid derivatives such as benzyl p-hydroxybenzoate,
Examples of aromatic sulfonic acid ester derivatives include benzyl p-benzyloxybenzoate and dibenzyl terephthalate, for example, phenyl p-toluenesulfonate, phenylmesitylenesulfonate,
-Methylphenyl mesitylenesulfonate and the like are carbonic acid or oxalic acid diester derivatives, for example, diphenyl carbonate, dibenzyl oxalate, dioxalic acid (4
-Methylbenzyl) ester, oxalic acid di (4-chlorobenzyl) ester and the like, as biphenyl derivatives,
For example, p-benzylbiphenyl, p-allyloxybiphenyl and the like are terphenyl derivatives such as m-
Terphenyl and the like are each exemplified.

In addition, lubricants such as zinc stearate, calcium stearate, and aluminum stearate, various surfactants, defoamers, ultraviolet absorbers and the like are added as required.

The thermochromic composition of the present invention is prepared using the above-mentioned materials by, for example, the following method. That is,
First, 3-diethylamine-7- (m-trifluoromethylanilino) fluoran and bis (3-allyl-4-hydroxyphenyl) sulfone were further added by a conventional method.
-Benzyloxy-4 '-(2-methylglycidyloxy) diphenylsulfone, 1,1,3-tris (2-methyl-4-hydroxy-5-t-cyclohexylphenyl) butane and 1,1,3-tris ( 2-methyl-4-
(Hydroxy-5-t-butylphenyl) butane in an organic solvent together with a binder or other additives, if necessary, in a dispersing machine such as a ball mill, attritor, or sand mill. After pulverized and dispersed, the mixture is mixed at a ratio within the range described in the present invention to obtain the thermosensitive coloring composition of the present invention.

Next, the heat-sensitive recording material of the present invention will be described. The heat-sensitive recording material of the present invention is obtained by applying the above-described heat-sensitive color-forming composition of the present invention on a support such as paper, plastic film, synthetic paper, or fiber sheet by a conventional method. In this case, the coating can be performed by a normal coating method using a bar coater, a roll coater, a reverse coater, a doctor coater, a microgravure coater, or the like, and printing by a method such as gravure, letterpress, flexo, or silk screen is also possible. . After the application, the organic solvent is dried and removed by, for example, air drying (normal temperature) or hot air drying up to about 150 ° C. to obtain the heat-sensitive recording material of the present invention. The heat-sensitive recording layer is usually formed on the support as a coating film having a dry weight of 0.5 to 20 g / m2. In the heat-sensitive recording material of the present invention, an overcoat layer of, for example, polyvinyl alcohol can be provided on the heat-sensitive recording layer, if necessary.

In an organic solvent, 3-diethylamino-7- (m-trifluoromethylanilino) fluoran, bis (3-allyl-4-hydroxyphenyl) sulfone, and 4-benzyloxy-4 are used as color-forming compounds. '-
(2-methylglycidyloxy) diphenyl sulfone,
1,1,3-tris (2-methyl-4-hydroxy-5
-T-cyclohexylphenyl) butane, 1,1,3-
The thermosensitive coloring composition of the present invention comprising one selected from tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane and a polymer compound is a paper,
It has good coatability or printability and adhesion to plastic films, synthetic papers, etc., and the heat-sensitive recording material of the present invention prepared using the same has excellent characteristics of coloring and preservation.

[0018]

EXAMPLES The present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. still,
In the examples, "parts" indicates parts by weight.

Example 1 A mixture having the following composition was ground with a sand grinder for 30 minutes to obtain a solution [A], a solution [B] and a solution [C], respectively. [A] solution: 3-diethylamino-7- (m-trifluoromethylanilino) fluorane 40 parts toluene 60 parts [B] solution: bis (3-allyl-4-hydroxyphenyl) sulfone 40 parts toluene 60 parts [ C] Solution: 4-benzyloxy-4 ′-(2-methylglycidyloxy) diphenylsulfone 40 parts Toluene 60 parts

Next, the mixture was mixed in the following ratio to obtain a thermosensitive coloring composition of the present invention. [A] solution 12.5 parts [B] solution 37.5 parts [C] solution 12.5 parts 20% methyl methacrylate / styrene copolymer (molecular weight = about 100,000) toluene solution 40.0 parts The thermosensitive coloring composition was applied on a white polyester film having a thickness of 188 μm to a dry weight of 6 g / m ^2, and dried to form a thermosensitive coloring layer. Further, the applied amount of the 10% PVA aqueous solution on the thermosensitive coloring layer when dried is 3 g.
/ M ² to obtain a heat-sensitive recording material of the present invention.

EXAMPLE 2 40% 1,1,3-tris (2-methyl-4-hydroxy-5-t-cyclohexylphenyl) pulverized and dispersed in the same manner as in Example 1 except that the solution [C] was used. A heat-sensitive recording material of the present invention was obtained in the same manner as in Example 1 using a butane dispersion.

EXAMPLE 3 40% 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) pulverized and dispersed in the same manner as in Example 1 except that the solution [C] was used. A heat-sensitive recording material of the present invention was obtained in the same manner as in Example 1 using a butane dispersion.

Example 4 A mixture having the following composition was pulverized for 30 minutes using a sand grinder to obtain a solution [D], a solution [E] and a solution [F]. [D] solution: 3-diethylamino-7- (m-trifluoromethylanilino) fluoran 25 parts tetralin 75 parts [E] solution: bis (3-allyl-4-hydroxyphenyl) sulfone 25 parts tetralin 75 parts [ F] Liquid: 4-benzyloxy-4 ′-(2-methylglycidyloxy) diphenylsulfone 25 parts Tetralin 75 parts

Then, the mixture was mixed at the following ratio to obtain a thermosensitive coloring composition of the present invention. [D] solution 16 parts [E] solution 48 parts [F] solution 16 parts 20% toluene solution of 20% methyl methacrylate / styrene / ethyl acrylate copolymer (molecular weight = about 100,000) 40 parts The hydrophilic composition was applied on a white polyester film having a thickness of 188 μm so as to have a dry weight of 6 g / m ^2, and dried to provide a thermosensitive coloring layer. Further, the applied amount of the 10% PVA aqueous solution on the thermosensitive coloring layer when dried is 3 g.
/ M ² to obtain a heat-sensitive recording material of the present invention.

Comparative Example 1 Comparative thermosensitive coloring was performed in the same manner as in Example 1 except that crystal violet lactone was used in place of 3-diethylamino-7- (m-trifluoromethylanilino) fluoran. A heat-sensitive coloring sheet for comparison was prepared from the composition.

Comparative Example 2 A comparative thermosensitive coloring composition was prepared in the same manner as in Example 1 except that bisphenol A was used instead of bis (3-allyl-4-hydroxyphenyl) sulfone of Example 1. Then, a thermosensitive coloring sheet for comparison was obtained from this. Using the heat-sensitive recording material of the present invention obtained as described above and a heat-sensitive coloring sheet for comparison, the following quality tests were carried out.

Table 1 Quality performance test Ground 1) Color density 2) Plasticizer resistance 3) Oil resistance 4) Example 1 0.06 1.55 1.53 1.54 Example 2 0.06 1.51 1.49 1.50 Example 3 0.06 1.50 1.50 1.48 Example 4 0.06 1.55 1.54 1.53 Comparative Example 1 0.75 1.46 1.11 1. 17 Comparative Example 2 0.29 1.48 0.49 0.52

1) Background: The undeveloped portion of the produced thermosensitive recording material or thermosensitive coloring sheet is measured by Macbeth reflection densitometer R
The value (reflection density) measured by D-914 type. 2) Color density: Macbeth reflection density of a portion printed by a commercially available thermal printer (D-805P, manufactured by Ishida Koki). 3) Plasticizer resistance: Macbeth reflection density after leaving the plastic eraser at a temperature of room temperature for 48 hours with a pressure of 100 to 200 g / cm ² applied to the portion printed by the printer. 4) Oil resistance: Macbeth reflection density after applying cottonseed oil to a portion printed by the above printer and wiping it after 10 seconds and leaving it to stand for 24 hours.

As is clear from the above-mentioned quality performance test table, the heat-sensitive recording material prepared by using the heat-sensitive color-forming composition of the present invention has little background fogging and stable images such as color density, plasticizer resistance and oil resistance. Excellent (preservation) property.

[0030]

According to the present invention, a thermosensitive color recording material (sheet) having little background fog and excellent color density and storage stability can be easily obtained.

Claims (5)

[Claims] 1. A thermosensitive coloring composition comprising a color developing compound, a color forming compound which reacts with the color developing compound under heating and develops a color, and a polymer compound in an organic solvent. It contains 3-diethylamino-7- (m-trifluoromethylanilino) fluoran as a compound, bis (3-allyl-4-hydroxyphenyl) sulfone as the color developing compound, and further contains 4-benzyloxy-4 ′
-(2-methylglycidyloxy) diphenylsulfone, 1,1,3-tris (2-methyl-4-hydroxy-5-t-cyclohexylphenyl) butane, 1,1,
A heat-sensitive coloring composition comprising one selected from 3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane. 2. The thermosensitive coloring composition according to claim 1, wherein the organic solvent is a hydrocarbon-based organic solvent. 3. The thermosensitive color-forming composition according to claim 2, wherein the hydrocarbon-based organic solvent is liquid at room temperature. 4. The thermosensitive color-forming composition according to claim 3, wherein the hydrocarbon organic solvent which is liquid at normal temperature is an aromatic hydrocarbon, a naphthenic hydrocarbon or a paraffinic hydrocarbon. 5. A thermosensitive recording material obtained by applying the thermosensitive coloring composition according to any one of claims 1 to 4 on a support and drying.