JPH11216950A - Thermal recording body for slip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal recording body for a slip which has high recording sensitivity and is subjected little to prime coat blushing due to pressure welding. SOLUTION: In a thermal recording body for a slip which has a pseudo- adhesive layer containing a pressure-sensitive adhesive, a second support, an intermediate layer and a thermal development layer containing a leuco dye and a coloring agent, in sequence, on at least one surface of a first support, an undercoat layer is made to contain plastic hollow particles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording material utilizing a color-forming reaction between a leuco dye and a coloring agent, and more particularly to a heat-sensitive recording material for a form having a pseudo-adhesive layer using a pressure-sensitive adhesive. belongs to.

[0002]

2. Description of the Related Art A heat-sensitive recording material utilizing a color-forming reaction between a leuco dye and a colorant has a thermosensitive color-forming layer containing a leuco dye and a colorant on a support. By heating with a pen, a laser beam or the like, the coloring agent in the thermosensitive coloring layer reacts instantaneously to form a recorded image. For example, JP-B-43-4160 and JP-B-45
As described in JP-A-14039 and the like, it has been widely known from the past.

[0003] Such a thermosensitive recording medium has such advantages that a recorded image can be formed by a relatively simple apparatus, maintenance is easy, and noise during recording is small. , Facsimile, terminal printers such as computers, POS printers, automatic ticket vending machines, and bar code label printers.

In recent years, with the improvement of information processing technology and distribution technology using a computer, a thermosensitive recording medium for a form having a thermosensitive recording paper is described in JP-A-55-17529. When processing is performed, there is a problem that background fogging occurs in the thermosensitive coloring layer.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermosensitive recording medium for a form which has a high recording sensitivity and has little background fog due to pressure bonding.

[0006]

Means for Solving the Problems At least on one side of a first support, a pseudo-adhesive layer containing a pressure-sensitive adhesive, a second support, an intermediate layer, and a thermosensitive layer containing a leuco dye and a colorant. As one means for solving the above-mentioned problems, in a thermosensitive recording medium for a form having a coloring layer in order, the present invention includes an intermediate layer containing plastic hollow particles.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a pseudo-adhesive layer containing a pressure-sensitive adhesive on at least one side of a first support.
A support, an intermediate layer, a thermosensitive recording medium for a form sequentially having a thermosensitive coloring layer containing a leuco dye and a colorant, wherein the intermediate layer contains plastic hollow particles,
The plastic hollow particle diameter is preferably about 0.2 to 30 μm. The amount used is 5 to 90% by weight, preferably about 10 to 80% by weight, based on the total solid content of the intermediate layer.

The hollowness of the plastic hollow particles (the ratio of the volume of the hollow portion to the total volume of the particles) is not particularly limited, but is preferably 30% or more, particularly preferably 40% or more.
When the specific average particle diameter is less than 0.2 μm, the improvement in recording sensitivity and recording image quality is small, and when it exceeds 30 μm, the recording image quality may be deteriorated.

Specific examples of the plastic used as the wall film material of the plastic hollow particles include, for example, polystyrene, poly-α-methylstyrene, poly-β-methylstyrene, polymethyl methacrylate, polyethyl methacrylate, and polymethacryl. Isopropyl acid, polyisobutyl methacrylate, polyacrylonitrile, polymethacrylonitrile, polyvinyl chloride, polyvinylidene chloride, polytetrafluoroethylene, polyvinyl formal, polyvinyl acetal, polyvinyl propional, polyvinyl butyral, polyvinyl isobutyral, polyvinyl tert- Resins such as butyl ether, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylcarbazole, cellulose acetate, cellulose triacetate, and polycarbonate are exemplified.

[0010] The hollow plastic particles have, for example, an alkali-soluble emulsion polymer as a core, and styrene,
A method in which ethylenically unsaturated monomers such as methyl methacrylate and vinyl chloride are polymerized to make the emulsion alkaline, or propane, butane, and pentane are encapsulated, and microcapsules made of plastic whose wall film material is made of plastic are heated and expanded. It can be obtained by:

The intermediate layer comprises, for example, an adhesive and plastic hollow particles used in the following thermosensitive coloring layer dissolved or dispersed in water using water as a medium, and an auxiliary agent which can be added to the following thermosensitive coloring layer as required. Is applied to one surface (surface) of the second support after drying, and the coating amount after drying is 3 to 15 g / m ² , preferably 6 to 12 g / m ² .
It is formed by coating and drying so as to have a thickness of about m ² . The amount of the adhesive used is 5 to 30 with respect to the total solid content of the intermediate layer.
% By weight.

Examples of the pressure-sensitive adhesive used for the pseudo adhesive layer include acrylic polymers, natural rubber, ethylene-vinyl acetate copolymers, acrylonitrile-butadiene copolymers, and styrene-butadiene copolymers. Resins such as coalesced, polyisobutylene, and polyvinyl ether.

[0013] In the pseudo-adhesive layer, for example, kaolin, talc, calcium carbonate,
Inorganic pigments such as aluminum hydroxide and amorphous silica, urea-formalin resin fillers, organic pigments such as raw starch and pulp powder, or lubricants such as stearamide, paraffin wax, zinc stearate and the like can be used in a pressure-sensitive adhesive. To 200% by weight, preferably about 80 to 150% by weight.

The pseudo-adhesive layer is prepared by mixing a pseudo-adhesive layer coating solution obtained by mixing and stirring a pressure-sensitive adhesive, a pigment or a lubricant with water or an organic solvent as a medium, on one side of a first support. (Front surface) or the other surface (back surface) of the second support is formed by coating and drying so that the coated amount after drying is about 10 to 40 g / m ² .

The thermosensitive recording medium for forms of the present invention may be provided with an adhesive layer and a release paper on the other surface (back side) of the first support.

The first and second supports include, for example, high quality paper, glassine paper, synthetic paper, film and the like. In addition, printing can be performed on the entire surface or a part of one surface of the first support in order to adjust the pseudo adhesive strength.
Of course, the surface of the heat-sensitive coloring layer on the first support and the second support may be subjected to, for example, printing of characters, ruled lines, drawings, etc., or OP varnish printing using ultraviolet curable ink.

As the leuco dye and color former contained in the thermosensitive coloring layer, various known ones can be used. Specific examples of such leuco dyes include, for example, the following. 3,3-bis (p-dimethylaminophenyl)-
6-dimethylaminophthalide, 3- (4-diethylamino-2-methylphenyl) -3- (4-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (N-
Ethyl-Np-tolyl) amino-7-N-methylanilinofluoran, 3-cyclohexylamino-6-chlorofluoran, 3-diethylamino-6-methyl-7-
Chlorofluorane, 3-diethylamino-7-chlorofluorane, 3- (N-ethyl-N-isoamyl) amino-6-methyl-7-anilinofluoran, 3- (N-methyl-N-cyclohexyl) amino -6-methyl-7-
Anilinofluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3-di (n-butyl) amino-6-methyl-7-anilinofluoran, 3-di (n
-Pentyl) amino-6-methyl-7-anilinofluoran, 3- (N-ethyl-p-toluidino) -6-methyl-7-anilinofluoran, 3- (N-ethyl-N-
Tetrahydrofurfurylamino) -6-methyl-7-anilinofluoran, 3-diethylamino-6-chloro-
7-anilinofluoran, 3-pyrrolidino-6-methyl-7-anilinofluoran, 3-piperidino-6-methyl-7-anilinofluoran, 3,3-bis [1- (4
-Methoxyphenyl) -1- (4-dimethylaminophenyl) ethylene-2-yl] -4,5,6,7-tetrachlorophthalide, 3-p- (p-dimethylaminoanilino) anilino-6 Methyl-7-chlorofluoran, 3
-P- (p-chloroanilino) anilino-6-methyl-
7-chlorofluorane, 3,6-bis (dimethylamino) fluoran-9-spiro-3 ′-(6′-dimethylamino) phthalide and the like

The leuco dye is not limited to these, and two or more leuco dyes can be used in combination. The amount of the leuco dye used is about 5 to 35% by weight based on the total solids of the thermosensitive coloring layer.

Examples of the coloring agent include 4,4'-isopropylidenediphenol, 4,4'-sec-butylidenediphenol, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 4'-cyclohexylidenediphenol, 2,4'-dihydroxyphenylsulfone, 4,4'-dihydroxydiphenylsulfone,
4-hydroxy-4'-isopropoxydiphenylsulfone, bis (3-allyl-4-hydroxyphenyl) sulfone, 4-hydroxy-4'-methyldiphenylsulfone, 4-hydroxy-4'-benzyloxydiphenylsulfone, 3, 4-dihydroxyphenyl-4'-methylphenylsulfone, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,4-[(4-hydroxyphenyl) isopropylidene] benzene, 4-hydroxybenzoic acid Benzyl, 4-hydroxybenzoic acid-
p-methoxybenzyl, a novolak type phenol resin,
Zinc 5-cyclohexylsalicylate, 5- [p- (2-
Methoxyphenoxyethoxy) cumyl] zinc salicylate zinc salt, 4- [3-p-tolylsulfonylpropyloxy] salicylate zinc salt, Np-tolylsulfonyl-N′-phenylurea, 4,4′-bis (p −
Tolylsulfonylaminocarbonylamino) diphenylmethane and the like.

The ratio of the leuco dye to the color former is not particularly limited.
0.5 to 10 parts by weight, preferably 1 to 10 parts by weight,
It is desirable to use about 5 parts by weight of a coloring agent.

The thermosensitive coloring layer may further contain a storage stabilizer for improving the storage stability of the recording portion and a sensitizer for increasing the recording sensitivity. As the storage stability improver, for example, 4-benzyloxyphenyl-4′-
(2-methyl-2,3-epoxypropyloxy) phenyl sulfone, 2,2′-methylenebis (4-methyl-
6-tert-butylphenol), 4,4′-thiobis (6-tert-butyl-m-cresol), 1,1,3-
Tris (2-methyl-4-hydroxy-5-cyclohexylphenyl) butane, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, N, N'-di-2 Storage stabilizers such as -naphthyl-p-phenylenediamine.

Examples of the sensitizer include stearic acid amide, methylenebisstearic acid amide, benzyl terephthalate, benzyl p-benzyloxybenzoate, 2-naphthylbenzyl ether, m-terphenyl, p-benzylbiphenyl, p-benzylbiphenyl Tolylbiphenyl ether, di (p-methoxyphenoxyethyl) ether, 1,2-
Di (3-methylphenoxy) ethane, 1,2-di (4-
Methylphenoxy) ethane, 1,2-di (4-methoxyphenoxy) ethane, 1,2-di (4-chlorophenoxy) ethane, 1,2-diphenoxyethane, 1- (4-
Methoxyphenoxy) -2- (3-methylphenoxy)
Ethane, p-methylthiophenylbenzyl ether,
1,4-di (phenylthio) butane, p-acetotoluidide, p-acetophenethidide, N-acetoacetyl-
p-Toluidine, di (β-biphenylethoxy) benzene, di-p-chlorobenzyl oxalate, di-p-methylbenzyl oxalate, dibenzyl oxalate and the like.

The amounts of the storage stabilizer and the sensitizer used are about 0.1 to 4 parts by weight with respect to 1 part by weight of the leuco dye.

The heat-sensitive color-forming layer is generally composed of water as a medium, for example, a leuco dye, a color former, a preservative stabilizer and a sensitizer finely dispersed in an average particle size of about 0.1 to 3 μm using a sand mill. The following adhesive and, if necessary, the following auxiliaries are mixed and agitated so that the coating amount after drying on the intermediate layer is about 3 to 12 g / m ^2. It is formed by coating and drying.

Examples of the adhesive contained in the thermosensitive coloring layer coating solution include starch and derivatives thereof, cellulose derivatives such as hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose and ethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, acrylamide. Acrylate copolymer, acrylamide / acrylate
Methacrylic acid copolymer, styrene / maleic anhydride copolymer alkali salt, isobutyl / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate,
Examples include water-soluble adhesives such as gelatin and casein, and water-dispersible adhesives such as vinyl acetate resin-based latex, urethane resin-based latex, acrylic resin-based latex, and styrene-butadiene resin-based latex. The amount of the adhesive used is preferably about 8 to 25% by weight based on the thermosensitive coloring layer.

Further, examples of auxiliary agents that can be added to the coating solution for the thermosensitive coloring layer include pigments such as kaolin, aluminum hydroxide, amorphous silica, calcium carbonate, zinc stearate, calcium stearate, paraffin wax, and polyethylene wax. And surfactants, fluorescent dyes, coloring dyes, ultraviolet absorbers, crosslinking agents, and the like.

As a method of applying the coating liquid for the intermediate layer, the coating liquid for the pseudo adhesive layer and the coating liquid for the thermosensitive coloring layer, for example, an air knife coater, a bar coater, a rod blade coater,
Examples thereof include a method using a coating machine such as a pure blade coater, a curtain coater, and a gravure coater.

[0028]

The present invention will be described in more detail with reference to the following Examples, but it should be understood that the present invention is by no means restricted thereto. In the examples, "parts" and "%" indicate "parts by weight" and "% by weight", respectively, unless otherwise specified.

Example 1 Preparation of Coating Solution for Intermediate Layer Microcapsules containing butane as plastic hollow particles (trade name: Matsumoto Microsphere F-3)
0, manufactured by Matsumoto Yushi-Seiyaku Co., Ltd.), 70 parts of a styrene-butadiene resin-based latex having a solid concentration of 48%, 20 parts of a 5% aqueous solution of carboxymethylcellulose (trade name: Cellogen 7A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), A composition comprising 2 parts of a 5% aqueous solution of sodium acid and 100 parts of water was mixed and stirred to obtain a coating liquid for an intermediate layer.

Preparation of Solution A A composition comprising 40 parts of 3-di (n-butyl) amino-6-methyl-7-alininofluoran, 20 parts of a 20% aqueous solution of sulfone-modified polyvinyl alcohol, and 40 parts of water is sand-milled. Was pulverized until the average particle diameter became 1.5 μm or less to obtain a liquid A.

Solution B Preparation: 40 parts of oxalic acid di-p-methylbenzyl ester, 20 parts of a 20% aqueous solution of sulfone-modified polyvinyl alcohol,
And a composition comprising water and 40 parts of water were pulverized with a sand mill until the average particle diameter became 2 μm or less to obtain a liquid B.

Solution C Preparation 40 parts of 4,4′-bis (p-toluenesulfonylaminocarbonylamino) diphenylmethane, 20 parts of a 20% aqueous solution of sulfone-modified polyvinyl alcohol, and water 40
Part C of the composition was pulverized by a sand mill until the average particle diameter became 2 μm or less to obtain a liquid C.

Preparation of Coating Solution for Thermosensitive Coloring Layer 25 parts of solution A, 40 parts of solution B, 40 parts of solution C, 30 parts of aluminum hydroxide, 10 parts of a 30% dispersion of zinc stearate,
10 parts of a 30% dispersion of paraffin wax, 1 part of polyvinyl alcohol (trade name: PVA110, manufactured by Kuraray Co., Ltd.)
100 parts of a 5% aqueous solution and 70 parts of water were stirred to obtain a thermosensitive coloring layer coating solution.

Preparation of Coating Liquid for Pseudo-Adhesive Layer 100 parts of ethylene-vinyl acetate copolymer latex having a solid content of 40% as a pressure-sensitive adhesive, and amorphous silica 100 having an average secondary particle diameter of 2.4 μm. Of a 40% aqueous solution of sodium polyacrylate and 200 parts of water were mixed and stirred to obtain a pseudo adhesive layer coating liquid.

Preparation of thermosensitive recording medium for forms Second support (basis weight: 78 g / m2)^TwoOne side of high quality paper)
The coating amount after drying the coating solution for the intermediate layer is 8 g / m^TwoBecomes
After coating and drying as in
The capsule was expanded to form an intermediate layer. Next, on the middle layer
The coating amount after drying the coating solution for the thermosensitive coloring layer is 5 g / m2.^TwoWhen
Apply and dry as necessary to form a thermosensitive coloring layer and record heat
I got a body. After forming each layer, use a super calender to
A lubrication treatment was performed. Printed for delivery form
Second support (basis weight 80 g / m 2^TwoPrinting side of high quality paper)
(The other side) has a coating amount of 3 after drying the pseudo adhesive layer coating liquid.
0 g / m ^TwoApply and dry to form a pseudo adhesive layer
After that, the pseudo adhesive layer side and the back side of the thermal recording paper
And a sealer using a metal crimping roll (product name:
(Lysealer 6860, manufactured by Toppan Forms)
No, treat the sealer gap as 50% of the total thickness
A thermosensitive recording material for a form was obtained.

Example 2 In the preparation of the coating solution for the intermediate layer of Example 1, butane was replaced with 70 parts of butane-containing microcapsules (trade name: Matsumoto Microsphere F-30, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.). (Product name: Matsumoto Microsphere F-30, manufactured by Matsumoto Yushi Seiyaku Co., Ltd.)
35 parts and calcined kaolin (trade name: Ansilex,
A thermosensitive recording medium for forms was obtained in the same manner as in Example 1 except that 85 parts of a 40% dispersion having an oil absorption of 110 ml / 100 g manufactured by EC Company was used.

Example 3 In the preparation of the coating solution for the intermediate layer of Example 1, hollow parts were replaced by hollow parts instead of 70 parts of butane-containing microcapsules (trade name: Matsumoto Microsphere F-30, manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.). The procedure was the same as in Example 1 except that 175 parts of a 40% dispersion of plastic hollow particles having a degree of 80%, an average particle diameter of 0.8 μm and a wall film material of polystyrene was used and an intermediate layer was formed as described below. To obtain a thermosensitive recording material for a form. Formation of Intermediate Layer On one surface of the second support (basis weight 78 g / m ² high quality paper), the intermediate layer coating solution is applied and dried so that the applied amount after drying is 8 g / m ^2. An intermediate layer was formed.

Comparative Example 1 In Example 2, instead of 70 parts of butane-containing microcapsules (trade name: Matsumoto Microsphere F-30, manufactured by Matsumoto Yushi Seiyaku Co., Ltd.), calcined kaolin (trade name: Ansilex, Inc.) was used. Made by EC, oil absorption 110ml / 1
A thermosensitive recording medium for a form was obtained in the same manner as in Example 2 except that 175 parts of a 40% dispersion of (00g) was used.

Comparative Example 2 In Example 2, kaolin (trade name: Matsumoto Microsphere F-30, manufactured by Matsumoto Yushi Seiyaku Co., Ltd.) was used instead of 70 parts of butane-containing microcapsules (trade name: Matsumoto Microsphere F-30).
Kao Fine 90, manufactured by SEAL Co., Ltd.)
A thermosensitive recording material for a form was obtained in the same manner as in Example 1 except that parts were used.

The pseudo-adhesive thermosensitive recording medium thus obtained was subjected to the following quality evaluation tests.
It described in.

(Initial Whiteness) The whiteness of the thermosensitive recording medium before preparing the thermosensitive recording medium for forms was measured with a Hunter whiteness meter.

(Background Fog Resistance) In order to evaluate the background fog of the obtained thermosensitive recording material for forms, the whiteness of the surface of the thermosensitive coloring layer was measured with a Hunter whiteness meter.

(Recording sensitivity) Thermal recording medium evaluation machine (trade name:
TH-PMD, manufactured by Okura Electric Co., Ltd., applied energy 0.4 m
J / dot), and the color density of the obtained recorded image is measured using a Macbeth densitometer (trade name: RD-914,
Macbeth) in visual mode.

[0044]

[Table 1]

[0045]

As shown in Table 1, all of the thermal recording media for forms of the present invention have a high recording sensitivity and an effect of reducing the background fogging due to the pressure bonding.

Claims (1)

[Claims] 1. A pseudo-adhesive layer containing a pressure-sensitive adhesive on at least one side of a first support, a second support, an intermediate layer,
A thermosensitive recording medium for forms, which has a thermosensitive coloring layer sequentially containing a leuco dye and a color former, wherein the intermediate layer contains plastic hollow particles.