JPH05301444A - Pressure-sensitive recording material - Google Patents

Abstract

PURPOSE:To make the light fastness of a developed color image excellent by including a diarylmethane compd. having a specific structure in a microcapsule of a polyurethane resin and/or a polyurea resin having a specific average particle size and a specific average film thickness as a basic dye and using an active clay substance as a developer. CONSTITUTION:In a thermal recording material utilizing the color reaction of a colorless-light-colored basic dye and a developer, as the basic dye, a diarylmethane compd. represented by formula I or II (wherein R1-R4 are a 1-5C alkyl group or a benzyl group and X-Z are H, a halogen atom, a 1-4C alkyl group or a 1-4C alkoxyl group) is used and this basis dye is included in a microcapsule with an average particle size of 3-16mum and an average film thickness of 0.1-0.7mum composed of a polyurethane resin and/or a polyurea resin and, as the developer, an active clay substance is used. As a result, the pressure-sensitive recording material imparting a developed color image excellent in light fastness, water resistance and chemical resistance is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive recording material which is excellent in light resistance and water resistance of a color image, and chemical resistance.

[0002]

2. Description of the Related Art A pressure-sensitive recording material is prepared by applying a microcapsule composition containing a microcapsule containing oil droplets in which a basic dye or the like is dissolved as a main component on one side of a support and on one side of the support. Is a color-developing layer containing a color-developing composition containing an electron-accepting color-developing agent (hereinafter simply referred to as a color-developing agent) as a main component, which is colored when brought into contact with the above basic dye to form a color-developing layer. Include a medium paper coated with a microcapsule composition and a lower paper coated with a color-developing composition on one surface of a support to form a color layer. These three types of sheets are used as upper paper, lower paper, Alternatively, the upper sheet, the middle sheet, and the lower sheet are combined in this order and put into practical use as a copy set. In addition, a self-coloring pressure-sensitive recording medium in which a microcapsule containing a basic dye and a coloring agent are coated on the same surface of a support to enable pressure-sensitive recording with one sheet is also known as one form of the pressure-sensitive recording medium. ing.

The performance that the pressure-sensitive recording medium should have is that it has a high color-developing speed and a sufficient color-developing density, does not cause fog, and has a sufficiently fast color image. With the diversification of demands in recent years, the robustness of color images is particularly sufficient. With the diversification of demands in recent years, there has been a demand for development of a pressure-sensitive recording material excellent in light resistance, water resistance, chemical resistance and the like of a color image.

Conventionally, triphenylmethane compounds, phthalide compounds, leucomethylene blue compounds and the like have been known as compounds which develop blue to blue violet, but satisfactory compounds have not been obtained yet. For example, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (that is, crystal violet lactone) has a fast color development speed and exhibits a deep blue color, but the light resistance of the color development material is extremely poor. In addition, the color density of the pressure-sensitive recording material may change depending on the writing pressure (printing pressure), and the characteristic peculiar to the pressure-sensitive recording material that causes color fog due to environmental factors such as unintentional pressure and heat and humidity can be improved. Is desired.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a pressure-sensitive recording material which is excellent in light resistance and water resistance of a color image, and further has chemical resistance, and which is also improved in the characteristics peculiar to the pressure-sensitive recording material. The purpose is to

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to solve such problems, and as a result, used a specific diarylmethane compound as a basic dye and converted it into a specific microcapsule. It is found that a pressure-sensitive recording material having excellent light resistance and water resistance and further chemical resistance, and having little color density change or color fog can be obtained by using it by encapsulating it and combining it with a specific colorant. The present invention has been completed.

The present invention provides a pressure-sensitive recording material utilizing a color reaction with a colorless or light-colored basic dye, wherein the basic dye is a diarylmethane represented by the following general formula [Chemical formula 1] or [Chemical formula 2]. The basic dye has an average particle diameter of 3 to 15 μm and an average film thickness of 0.1 to 0.7 μ.
The pressure-sensitive recording material is characterized by being encapsulated in a polyurethane resin and / or polyurea resin microcapsule of m and using an activated clay substance as a coloring agent.

[0008]

[Chemical 1]

[0009]

[Chemical 2]

[In the formula, R _{1 to} R ₄ are respectively C _{1 to} C ₅
Is an alkyl group or a benzyl group, and X, Y and Z are each a hydrogen atom, a halogen atom, a C _{1 to} C ₄ alkyl group or a C _{1 to} C ₄ alkoxyl group. ]

[0011]

The diarylmethane compound represented by the general formula [Chemical formula 1] or [Chemical formula 2] used in the present invention includes, for example, the following. Bis [4,4'-bis (dimethylaminobenzhydryl)] ether, bis [4,4 '
-Bis (diethylaminobenzhydryl)] ether,
Bis [4,4'-bis (di-n-butylaminobenzhydryl)] ether, bis (4-dimethylamino-4 '
-Diethylaminobenzhydryl) ether, bis (4
-Dimethylamino-4'-di-n-propylaminobenzhydryl) ether, bis [4,4'-bis (N-methyl-N-ethylaminobenzhydryl)] ether,
Bis [4,4′-bis (N-methyl-Nn-propylaminobenzhydryl)] ether, bis [4,4′-
Bis (N-methyl-N-benzylaminobenzhydryl)] ether, bis [4,4'-bis (N-ethyl-
N-benzylaminobenzhydryl)] ether,
[4,4'-bis (dimethylaminobenzhydryl)]
-Benzyl-ether, [4,4'-bis (diethylaminobenzhydryl)]-benzyl-ether, [4
4'-bis (di-n-propylaminobenzhydryl)]-benzyl-ether, (4-dimethylamino-
4'-diethylaminobenzhydryl) -benzyl-ether, (4-diethylamino-4'-di-n-propylaminobenzhydryl) -benzyl-ether,
[4,4'-bis (N-methyl-N-ethylaminobenzhydryl)]-benzyl-ether, [4,4'-bis (N-methyl-Nn-propylaminobenzhydryl)]- Benzyl-ether, [4,4'-bis (N-
Ethyl-N-benzylaminobenzhydryl)]-benzyl-ether, [4,4'-bis (dimethylaminobenzhydryl)]-(4-methylbenzyl) -ether, [4,4'-bis (dimethyl) Aminobenzhydryl)]-(2-methylbenzyl) -ether, [4,
4'-bis (dimethylaminobenzhydryl)]-(4
-Ethylbenzyl) -ether, [4,4'-bis (dimethylaminobenzhydryl)]-(4-tert-butylbenzyl) -ether, [4,4'-bis (dimethylaminobenzhydryl)]- (4-methoxybenzyl)-
Ether, [4,4'-bis (dimethylaminobenzhydryl)]-(4-isopropoxybenzyl) -ether, [4,4'-bis (dimethylaminobenzhydryl)]-(4-chlorobenzyl) -Ether, [4,
4'-bis (dimethylaminobenzhydryl)]-
(2,4-dichlorobenzyl) -ether, [4,4 '
-Bis (dimethylaminobenzhydryl)]-(2
4,6-trichlorobenzyl) -ether, [4,4 '
-Bis (diethylaminobenzhydryl)]-(4-bromobenzyl) -ether, [4,4'-bis (diethylaminobenzhydryl)]-(3-chloro-4-ethoxybenzyl) -ether, [4. 4'-bis (diethylaminobenzhydryl)]-(2-chloro-5-methoxybenzyl) -ether and the like. Of course, the dyes are not limited to these dyes, and two or more kinds of dyes can be used in combination as required.

The present invention has the general formula [Chemical formula 1] or [Chemical formula 2]
The use of a diarylmethane-based compound represented by the following, within the range that does not impair the effects of the present invention, other known basic dyes, for example, triarylmethane-based compounds, triphenylmethanephthalide or An azaphthalide compound, an indolylphthalide or an azaphthalide compound, a fluoran compound, a fanothiazine compound, a rhodamine lactam compound, a triazene compound, a spicopyran compound, a leuco auramine compound and the like can be used in combination.

Among these basic dyes, when a triarylmethane compound represented by the following general formula [Chemical Formula 3] is used in combination, the storability of images is further improved.
preferable.

[0014]

[Chemical 3]

[Wherein R ₅ is a C ₁ -C ₈ alkyl group or a benzyl group, R ₆ and R ₇ are each a hydrogen atom, and C
Alkyl group of ₁ -C _4, a benzyl group or a phenyl group. The phenyl group is a C ₁ -C ₄ alkyl group, C ₁
It may be substituted with a C ₄ -alkoxyl group, a benzyl group, a benzyloxy group or a halogen atom. n is 1 to 3
Indicates an integer. ]

Examples of the triarylmethane compound represented by the general formula [Chemical Formula 3] include the following. (Carbazol-3-yl) -bis (4-dimethylaminophenyl) methane, (9-methyl-carbazol-3-yl) -bis (4-dimethylaminophenyl) methane,
(9-Ethyl-carbazol-3-yl) -bis (4-
Dimethylaminophenyl) methane, (9-n-butyl-
Carbazol-3-yl) -bis (4-dimethylaminophenyl) methane, (9-n-butyl-carbazole-
3-yl) -bis (4-diethylaminophenyl) methane, (9-n-butyl-carbazol-3-yl) -bis (4-di-n-butylaminophenyl) methane, (9
-Methyl-carbazol-3-yl) -bis [4- (N
-Benzyl-N-methylamino) phenyl] methane,
(9-Ethyl-carbazol-3-yl) -bis [4-
(N-phenyl-N-methylamino) phenyl] methane, (9-n-butyl-carbazol-3-yl) -bis [4- (N-phenyl-N-methylamino) phenyl] methane, (9-n -Octyl-carbazole-3-
Yl) -bis [4- (N-phenyl-N-methylamino) phenyl] methane, (9-ethyl-carbazole-
3-yl) -bis [4- (N-methyl-N-p-methoxyphenylamino) phenyl] methane, (9-ethyl-
Carbazol-3-yl) -bis [4- (N-methyl-
N-p-benzyloxyphenylamino) phenyl] methane, (9-n-butyl-carbazol-3-yl)-
Bis [4- (N-methyl-Np-benzyloxyphenylamino) phenyl] methane, bis (9-ethyl-carbazol-3-yl)-(4-dimethylaminophenyl) methane, bis (9-n- Butyl-carbazole-3
-Yl)-(4-diethylaminophenyl) methane, bis (9-ethyl-carbazol-3-yl)-[4-
(N-phenyl-N-methylamino) phenyl] methane, bis (9-n-butyl-carbazol-3-yl)
-[4- (N-phenyl-N-methylamino) phenyl] methane, bis (9-n-octyl-carbazole-
3-yl)-[4- (N-phenyl-N-methylamino) phenyl] methane, bis (9-benzyl-carbazol-3-yl)-[4- (N-phenyl-N-methylamino) phenyl] Methane, bis (9-ethyl-carbazol-3-yl)-[4- (N-methyl-Np-methoxyphenylamino) phenyl] methane, tris (9
-Ethyl-carbazol-3-yl) methane, tris (9-n-butyl-carbazol-3-yl) methane,
Tris (9-n-octyl-carbazol-3-yl)
Methane, etc. Of course, the dyes are not limited to these dyes, and two or more kinds of dyes can be used in combination as required.

In the present invention, when the triarylmethane compound represented by [Chemical Formula 3] is used, the amount used is
Although not particularly limited, it is usually used in an amount of 10 to 300 parts, preferably 50 to 200 parts, per 100 parts of the diarylmethane compound represented by [Chemical Formula 1] or [Chemical Formula 2]. Incidentally, if it is less than 10 parts, there is almost no effect in improving the storability of an image, and if it is used in excess of 300 parts, a problem is likely to occur in color developability.

In the present invention, the wall film agent of the microcapsules encapsulating the basic dye is further specified as a polyurethane resin and / or polyurea resin-based material to suppress the occurrence of color stains, and further, the average particle thereof. By limiting the diameter to 3 to 15 μm, the unevenness and discontinuity of the coloring density due to the difference in the writing pressure can be eliminated, and the coloring stain caused by the unintended pressure can be more remarkably suppressed. The average film thickness of the microcapsules is 0.1 to 0.7.
By specifying μm, color fog caused by environmental factors such as heat and humidity is further improved, and as a result, a sharp and clear print can be formed and a pressure-sensitive recording material having stable quality characteristics is obtained. ..

When the average particle size of the capsules is less than 3 μm, the color density is lowered and the readability is deteriorated.
If it exceeds 15 μm, color stains are produced. Therefore, it is necessary to adjust the average particle size of the capsule in the range of 3 to 15 μm, preferably 5 to 10 μm. Furthermore, the average film thickness is 0.1μ
When the thickness is less than m, unnecessary color stains increase to 0.7.
If it exceeds 0.1 μm, the color development sensitivity decreases, so the average film thickness of the capsule is 0.1 to 0.7 μm, preferably 0.1 to 0.7 μm.
It is adjusted in the range of 0.4 μm.

The basic dye used in the present invention may be mixed with various known UV absorbers, if necessary, and then cottonseed oil, hydrogenated terphenyl, hydrogenated terphenyl derivative, alkylbiphenyl, alkylnaphthalene, diarylalkane, Microcapsules made of polyurethane resin and / or polyurea resin wall membrane materials by dissolving in a natural or synthetic hydrophobic medium such as paraffin, naphthenic oil, dibasic acid ester such as phthalic acid ester, etc. and by interfacial polymerization method. It is contained inside. Then, by appropriately adjusting the encapsulation conditions at that time, a capsule having the above-mentioned specific average particle size and average film thickness is prepared.

Polyurethane resin and polyurea resin wall membrane capsules are made of polyisocyanate and water, polyisocyanate and polyol, isothiocyanate and water, isothiocyanate and polyol, polyisocyanate and polyamine, isothiocyanate and polyamine, etc. It is manufactured by an interfacial polymerization method.

Microcapsules containing a specific basic dye thus prepared and having a specific average particle diameter and average film thickness are used for adhering polyvinyl alcohols, starches, carboxymethylcelluloses, latexes, etc. according to a conventional method. Various materials such as an agent, a pulp powder, and a raw starch powder, and a variety of materials such as a tilting agent are appropriately mixed to prepare a capsule coating solution, which is used for producing upper paper, middle paper, self-coloring pressure-sensitive recording material, and the like.

The present invention is characterized in that an active clay substance is used as a colorant-containing layer combined with the microcapsule coated surface of the upper paper or the middle paper or as a colorant of the self-coloring type pressure-sensitive recording material. .. Examples of the activated clay substance include acid clay, activated clay, attapulgite, zeolite, pentonite, and clay substances such as kaolin. Among them, activated clay is preferable. Usually, activated clay is chemically or physically synthesized by blending, for example, an acid-treated montmorillonite group clay mineral with magnesium carbonate and a hydroxide of magnesium or calcium. In addition,
As the color former, various known organic colorants may be used in combination as long as they do not hinder the present invention, for example, phenol derivatives, salicylic acid derivatives, aromatic carboxylic acid derivatives and their metal salts, novolac resins and the like. ..

The coloring agent coating liquid contains the above-mentioned activated clay substance,
Usually, it is prepared by a method such as dispersion in water together with adhesives. Examples of adhesives include starch, casein, gum arabic, carboxymethyl cellulose, polyvinyl alcohol, styrene / butadiene copolymer latex, vinyl acetate latex and the like. Also, in the coating liquid,
If necessary, inorganic pigments such as zinc oxide, magnesium oxide, titanium oxide, aluminum hydroxide, calcium carbonate, magnesium sulfate and calcium sulfate and various auxiliaries known in the field of pressure-sensitive copying paper production can be appropriately added.

The method of applying the coating liquid is not particularly limited, and for example, an on-machine or off-machine coater equipped with an appropriate coating device such as an air knife coater, a roll coater, a blade coater, a rod coater, a curtain coater, and a lip coater, It is applied to a support such as paper, synthetic paper or film so that the dry weight is about ^{2 to} 10 g / m ² .

[0026]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited thereto. In addition, unless otherwise indicated, the part and% in an example show a weight part and weight%, respectively.

Example 1 [Preparation of Coloring Agent Coating Liquid] Activated clay (trade name: Shilton DR
-1, Mizusawa Chemical Co., Ltd.) 100 parts, magnesium oxide
A coloring agent coating liquid was prepared by adding 1 part, 20 parts (solid content) of carboxy-modified styrene / butadiene copolymer latex, and 1 part of sodium carboxymethyl cellulose.

[Production of lower paper] 40 g of the above coloring agent coating liquid
/ M ² of base paper was coated and dried by an air knife coater so that the dry weight was 5 g / m ² , and calendered to prepare a pressure-sensitive recording lower paper.

[Preparation of Microcapsule Dispersion] In a stirring and mixing container equipped with a heating device, 150 parts of a 3% aqueous solution of polyvinyl alcohol (trade name: PVA-117, manufactured by Kuraray Co., Ltd.) was added to prepare an aqueous medium for capsule production. And Separately, 100 parts of alkylnaphthalene (trade name: KMC oil, manufactured by Kureha Chemical Co., Ltd.) was used as a basic dye, and bis [4,4]
4'-bis (dimethylaminobenzhydryl)] ether was dissolved in 10 parts, and further, 5 parts of polymethylene polyphenyl isocyanate (trade name: Millionate MR400, manufactured by Nippon Polyurethane Industry Co., Ltd.) and 2-isocyanatoethyl-2,6. -Diisocyanate hexaate (trade name:
(T-100, manufactured by Toray Industries, Inc.) A solution obtained by dissolving 2 parts is used as a capsule core substance in the above-mentioned aqueous medium for capsule preparation.
The dispersion was carried out for 1 minute at 10,000 rpm using a TK homomixer.

Diethylenetriamine 1 was added to this emulsion dispersion.
Parts and after stirring for 30 minutes at room temperature, the system temperature was adjusted to 7
The temperature was raised to 0 ° C. and the reaction was continued for 3 hours while continuing stirring.
The temperature was lowered to room temperature to prepare a microcapsule composed of a polyurea resin / polyurethane resin wall film having an average particle size of 5.7 μm and an average film thickness of 0.16 μm.

[Preparation of microcapsule coating solution] To 100 parts by weight (solid content) of the microcapsule dispersion thus obtained, 70 parts of wheat starch and 20 parts of dissolved oxidized starch (solid content) were added to obtain microcapsules. A coating liquid was prepared.

[Manufacture of Medium Paper] The microcapsule coating liquid is applied to the surface of the lower paper opposite to the surface coated with the coloring agent with an air knife coater so as to have a dry weight of 4 g / m ² , and then dried. A medium pressure recording paper was obtained.

Examples 2 to 7 In the preparation of the microcapsule dispersion of Example 1, six types of pressure-sensitive recording medium paper were prepared in the same manner as in Example 1 except that the compounds shown below were used as the basic dye. Got The average particle size and the average film thickness of the prepared microcapsules were 5.4 to 5.8 μm and 0.1, respectively.
It was in the range of 5 to 0.19 μm.

Example 2: 10 parts of bis [4,4'-bis (diethylaminobenzhydryl)] ether Example 3: 10 parts of [4,4'-bis (dimethylaminobenzhydryl)]-benzyl-ether

Example 4: 5 parts of bis [4,4'-bis (dimethylaminobenzhydryl)] ether and (9-
n-butyl-carbazol-3-yl) -bis [4-
(N-phenyl-N-methylamino) phenyl] methane 5 parts Example 5: Bis [4,4'-bis (dimethylaminobenzhydryl)] ether 5 parts and bis (9-n-ethyl-carbazole-) 3-yl)-[4- (N-phenyl-N-methylamino) phenyl] methane 5 parts

Example 6: 5 parts of [4,4'-bis (dimethylaminobenzhydryl)]-benzyl-ether and (9-n-butyl-carbazol-3-yl) -bis [4- (N -Phenyl-N-methylamino) phenyl] methane 5 parts Example 7: Bis [4,4'-bis (diethylaminobenzhydryl)] ether 3 parts, (9-n-butyl-carbazol-3-yl)- Bis [4- (N-phenyl-
N-methylamino) phenyl] methane 3 parts, 3,3-
Bis (p-dimethylaminophenyl) -6-dimethylaminophthalide 4 parts

Example 8 An average was prepared in the same manner as in Example 1 except that the emulsification time of the capsule core substance and the aqueous medium for capsule preparation was changed from 1 minute to 30 seconds in the preparation of the microcapsule dispersion liquid of Example 1. Particle size is 12.3 μm, average film thickness is 0.30 μm
Capsules of No. 1 were prepared and the same procedure as in Example 1 was performed to obtain a pressure-sensitive recording medium paper.

Example 9 The same as Example 1 except that the amount of polymethylene polyphenyl isocyanate used was reduced from 5 parts to 3 parts in the preparation of the microcapsule dispersion of Example 1. And the average particle size is 4.5 μm
Then, capsules having an average film thickness of 0.13 μm were prepared, and a pressure-sensitive recording medium paper was obtained in the same manner as in Example 1.

Comparative Example 1 In the preparation of the microcapsule dispersion of Example 1, except that 10 parts of 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide was used as the basic dye, Similar to Example 1, the average particle size is 5.8μ.
m and an average film thickness of 0.18 μm were prepared, and a pressure-sensitive recording medium paper was obtained in the same manner as in Example 1.

Comparative Example 2 In the preparation of the coloring agent coating liquid of Example 1, 3,5-bis (α-methylbenzyl) was used instead of 100 parts of activated clay (trade name: Shilton DR-1, manufactured by Mizusawa Chemical Co., Ltd.). An intermediate paper for pressure-sensitive recording was obtained in the same manner as in Example 1 except that 20 parts of salicylic acid zinc salt and 80 parts of kaolin were used.

Comparative Example 3 In the preparation of the microcapsule dispersion of Example 1, the same procedure as in Example 1 was carried out except that the emulsification time of the capsule core substance and the aqueous medium for capsule production was changed from 1 minute to 15 seconds. Particle size is 15.3 μm, average film thickness is 0.40
A polyurea resin / polyurethane resin wall film capsule having a thickness of μm was prepared, and a pressure-sensitive recording medium paper was obtained in the same manner as in Example 1.

Comparative Example 4 An average particle size of 4 was obtained in the same manner as in Example 1 except that the amount of polymethylene polyphenyl isocyanate used was reduced from 5 parts to 1 part in the preparation of the microcapsule dispersion of Example 1. A polyurea resin / polyurethane resin wall film capsule having a thickness of 0.5 μm and an average film thickness of 0.05 μm was prepared, and a pressure-sensitive recording medium paper was obtained in the same manner as in Example 1 below.

Comparative Example 5 In the preparation of the microcapsule dispersion of Example 1, the amount of polymethylene polyphenyl isocyanate used was increased from 5 parts to 10 parts during the preparation of the microcapsule dispersion, and the emulsification time was from 1 minute to 15 minutes. Capsules having an average particle size of 20.4 μm and an average film thickness of 0.80 μm were prepared in the same manner as in Example 1 except that the time was changed to 2 seconds, and the same procedure as in Example 1 was performed to obtain a pressure-sensitive recording medium sheet. It was

Comparative Example 6 In the preparation of the microcapsule dispersion of Example 1, the emulsification condition of the capsule core substance and the aqueous medium for capsule preparation was changed from 1 minute at 10000 rpm to 2 minutes at 20000 rpm. Except for the above, capsules having an average particle diameter of 2.1 μm and an average film thickness of 0.13 μm were prepared in the same manner as in Example 1, and the same procedure as in Example 1 was performed to obtain a pressure-sensitive recording medium paper.

Comparative Example 7 10 parts of bis [4,4'-bis (dimethylaminobenzhydryl)] ether as a basic dye was dissolved in 100 parts of alkyldiphenylethane. Separately, 25 parts of pigskin gelatin having an isoelectric point of 8 as an encapsulating agent and 25 parts of arabic rubber were dissolved in 300 parts of warm water at 50 ° C. The above-mentioned oil containing a color-forming agent was added to this gelatin-arabic gum mixed solution while stirring and emulsified and dispersed.

This emulsion was further diluted with 1000 parts of warm water, and acetic acid was gradually added dropwise to adjust the pH of the solution to 4 to 4.3. The encapsulating agent was deposited around the oil droplets and the sol was formed. A capsule was produced. After the capsule was cooled and gelated to about 10 ° C., 10 parts of a 25% aqueous solution of glutaraldehyde was added to cure the capsule, and the average particle diameter was 6.1 μm, and the average thickness of the wall film was 0.38 μm. The gelatin-based wall membrane capsule of Example 1 was prepared, and a pressure-sensitive recording medium paper was prepared in the same manner as in Example 1.

Using the 16 kinds of pressure-sensitive recording medium paper thus obtained, various performance comparison tests were conducted, and the results are shown in Table 1.

[Printing Density] The prepared pressure-sensitive recording medium is overlaid so that the capsule coating surface and the coloring agent coating surface face each other, and after printing with a dot printer, the color density is measured with a Macbeth densitometer (manufactured by Macbeth Co.). , RD-914 type) using a visual filter.

[Lightfastness Test] This printed color surface (coloring agent coated surface) was exposed to direct sunlight for 20 hours, and then the color density was measured again with a Macbeth densitometer.

[Water resistance test] The printed inner paper was allowed to stand in water for 48 hours, and then the color density was measured again with a Macbeth densitometer.

[Plasticizer resistance test] A vinyl chloride film was superposed on the color-developed surface of the print and allowed to stand at 40 ° C. for 3 days.
The color density was measured again with a Macbeth densitometer.

[Contact Stain Resistance Test] The prepared medium pressure-sensitive recording medium was superposed so that the capsule-coated surface and the color-developing agent-coated surface were opposed to each other, and a load of 20 kg / cm ² was applied for 1 minute. The degree of color stain on the surface coated with the color developing agent was visually determined according to the following evaluation criteria. (Evaluation Criteria) ○: Almost no dirt ×: Significantly dirt

[Scratch Resistance Staining Test] The prepared pressure-sensitive recording medium papers were superposed so that the capsule-coated surface and the coloring agent-coated surface were opposed to each other, and rubbed 5 times under a load of 4 kg / cm ^2. After the matching, the degree of color stain on the surface coated with the color developing agent was visually determined according to the following evaluation criteria. (Evaluation Criteria) ○: Almost no dirt ×: Significantly dirt

[0054]

[Table 1]

[0055]

As is apparent from the results shown in Table 1, a specific diarylmethane compound was used as a basic dye, and the specific diarylmethane compound was used by being encapsulated in specific microcapsules and further combined with a specific coloring agent. The pressure-sensitive recording material was an excellent pressure-sensitive recording material having excellent storage stability of recorded images and less color fog.

[Procedure amendment]

[Submission date] August 20, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction content]

[Wherein R ₅ is a hydrogen atom, a C ₁ -C ₈ alkyl group or a benzyl group, and R ₆ and R ₇ are each a hydrogen atom, a C ₁ -C ₄ alkyl group, a benzyl group or a phenyl group. Indicates a group. The phenyl group is a C ₁ -C ₄ alkyl group, a C ₁ -C ₄ alkoxyl group, a benzyl group,
It may be substituted with a benzyloxy group or a halogen atom. n shows the integer of 1-3. )

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masato Tanaka Inventor Masato Tanaka 4-3-1, Jokoji, Amagasaki, Hyogo Kanzaki Paper Mill Kanzaki Mill Co., Ltd.

Claims (1)

[Claims] 1. A pressure-sensitive recording material utilizing a color reaction with a colorless or pale basic dye, wherein the basic dye is a diarylmethane compound represented by the following general formula [Chemical formula 1] or [Chemical formula 2]. The basic dye is contained in a polyurethane resin and / or polyurea resin microcapsule having an average particle diameter of 3 to 15 μm and an average film thickness of 0.1 to 0.7 μm, and a coloring agent. A pressure-sensitive recording material characterized by using an activated clay substance as a material. [Chemical 1] [Chemical 2] [Wherein, R _{1 to} R ₄ are each a C _{1 to} C ₅ alkyl group or a benzyl group, X, Y and Z are each a hydrogen atom,
Halogen atom, C ₁ -C ₄ alkyl or C ₁ -C
_{4 represents} an alkoxyl group. ]