JPH1134493A - Multiple thermographic sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple thermographic sheet having excellent thermal recordability and pressure sensitive recordability. SOLUTION: In the multiple thermographic sheet comprising an upper leaf recording sheet having a thermal recording layer containing leuco dye and colorant and provided on one surface of an upper leaf base material sheet and a thermal transfer layer containing leuco dye and heat fusible organic compound and provided on the other surface of the base material sheet, and a lower leaf recording sheet having a thermal transfer receiving layer containing colorant and adhesive on one surface of a lower leaf base material sheet, the thermal transfer receiving layer contains, as the colorant, mono (or bis or tri or tetrakis) [poly(to 4) [ω-hydro([poly(1-7)α-methylbenz]-α-il)benzyl]zinc salicylate and 3,5-di(α-methylbenzyl)zinc salicylate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording sheet utilizing a color-forming reaction between a leuco dye and a color former, and more particularly to a heat-sensitive multiple copying sheet capable of performing multiple copying by heat or writing pressure.

[0002]

2. Description of the Related Art A thermosensitive recording medium is known which utilizes a color reaction between a leuco dye and a coloring agent to react both coloring materials with heat energy from a thermal head to obtain a recorded image. . Such a thermosensitive recording medium is relatively inexpensive, and its recording equipment is compact and easy to maintain, so that it is used not only as a recording medium for facsimile machines and various computers but also in a wide range of fields. In particular, after using thermal recordings as receipts,
There is an increasing demand for a thermosensitive recording medium capable of recording on a number of sheets with a single thermal recording.

As a means for recording on a number of sheets in one thermal recording, it is conceivable to apply thermal recording in a state where a plurality of thermal recording media having a thermal recording layer formed on a support are stacked. Clear thermal recording images cannot be formed on a plurality of sheets by the thermal head.

[0004] In order to obtain clear thermal recording images on a plurality of sheets, a thermal recording layer containing a leuco dye and a coloring agent is provided on at least one surface of the upper leaf base sheet, and the leuco dye is provided on the other surface. An upper leaf recording sheet provided with a thermal transfer layer containing a heat-fusible organic compound, and a lower leaf recording sheet provided with a thermal transfer receiving layer containing a colorant and an adhesive on one surface of a lower leaf base sheet Thermal multiple copy sheet
7-96895 and JP-A-57-96896. However, in recent years, the range of applications of thermal recording media has expanded, especially in credit card applications, where the amount of money, date and time, details, etc. are recorded on multiple sheets at once by thermal recording, and customer pressure is recorded by writing pressure with a pen such as a ballpoint pen. Signs must be recorded on multiple sheets at once. There has been no satisfactory heat-sensitive multiple copy sheet that satisfies both the heat-sensitive recording property and the pressure-sensitive recording property at the same time.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-sensitive multiplex copy sheet having excellent heat-sensitive recording properties and pressure-sensitive recording properties.

[0006]

Means for Solving the Problems At least a heat-sensitive recording layer containing a leuco dye and a coloring agent is provided on one surface of an upper leaf base material sheet, and a leuco dye and a heat-fusible organic compound are contained on the other surface. In a heat-sensitive multiplex copying sheet having an upper leaf recording sheet provided with a thermal transfer layer and a lower leaf recording sheet provided with a thermal transfer receiving layer containing a colorant and an adhesive on one surface of a lower leaf base sheet, As a means for solving the problem, the present invention relates to a method for preparing a color transfer agent such as mono (or bis or tri or tetrakis) [poly (0 to 4) [ω-hydro [poly (1 to 7)] α-methylbenz] -α-yl] benzyl] zinc salicylate and zinc 3,5-di (α-methylbenzyl) salicylate. In the above means, by further adding zinc oxide as a pigment in the thermal transfer receiving layer, the heat-sensitive recording property and the pressure-sensitive recording property are further improved.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a heat sensitive recording layer containing a leuco dye and a color former on at least one surface of an upper leaf base sheet, and a leuco dye and a heat-fusible organic compound on the other surface. A thermal transfer multi-copy sheet having an upper leaf recording sheet provided with a thermal transfer layer containing therein, and a lower leaf recording sheet provided with a thermal transfer receiving layer containing a colorant and an adhesive on one surface of a lower leaf base sheet. Zinc mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α-methylbenz] -α-yl] benzyl] salicylate as a color former in the receiving layer; It is characterized by containing a specific colorant such as zinc 3,5-di (α-methylbenzyl) salicylate. The amount of the specific colorant is not particularly limited, but is based on the total solid content of the thermal transfer receiving layer. 10-7 About weight% is preferred.

In certain color formers, mono (or bis or tris or tetrakis) [poly (0-4) [ω
The ratio of zinc hydro- [poly (1-7) α-methylbenz] -α-yl] benzyl] salicylate to zinc 3,5-di (α-methylbenzyl) salicylate was 1: 5 by weight. To 5: 1, preferably about 1: 3 to 3: 1. As long as the desired effects of the present invention are not impaired, other colorants contained in the following heat-sensitive recording layer may be used in addition to the specific colorant.

In the thermal transfer receiving layer, the following adhesives together with a specific coloring agent, and if necessary, pigments such as kaolin, calcium carbonate, amorphous silica, titanium oxide, aluminum hydroxide, calcined kaolin, zinc oxide, fluorescent Auxiliary agents such as dyes, coloring dyes, surfactants, and waterproofing agents are contained. In particular, when zinc oxide is contained as a pigment, effects excellent in heat-sensitive recording property and pressure-sensitive recording property can be obtained. The amount of zinc oxide used is preferably about 5 to 40% by weight based on the total solid content of the thermal transfer receiving layer.

Specific examples of the adhesive contained in the thermal transfer receiving layer include, for example, starch, oxidized starch, completely (partially) saponified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, silicon-modified polyvinyl alcohol, Styrene-
Water-soluble adhesives such as maleic acid copolymer salts, ethylene-acrylic acid copolymer salts, isobutylene-maleic acid copolymer salts, and acrylic resins, urethane resins,
Hydrophobic adhesives such as styrene-butadiene resin, vinyl acetate resin, vinylidene chloride resin, and vinyl acetate-vinyl chloride resin are exemplified. Above all, hydrophobic adhesives,
In particular, a styrene-butadiene-based resin, which is a hydrophobic adhesive, is preferred because an excellent pressure-sensitive recording effect can be obtained.

The thermal transfer receiving layer is generally formed by using water as a medium,
A heat transfer receiving layer coating liquid obtained by mixing and stirring a specific colorant dispersion liquid having an average particle diameter of 3 μm or less, an adhesive, and, if necessary, an auxiliary agent such as a pigment and a waterproofing agent, is used. The coated amount after drying on one surface of the lower leaf base sheet is 1 to 7 g /
It is formed by coating and drying so as to have a thickness of about m ² . When the adhesive is a hydrophobic adhesive, it is added to the coating liquid in the form of a latex.

As the specific colorant dispersion contained in the coating solution for a thermal transfer receiving layer, at least one of the specific colorants is a volatile organic solvent such as toluene, methyl ethyl ketone, or ethyl acetate and, if necessary, diisopropyl alcohol. A solution obtained by emulsifying and dispersing a solution dissolved together with a nonvolatile organic solvent such as naphthalene and then volatilizing the volatile organic solvent is preferable. In particular, it is preferable that both of the specific colorants are emulsified and dispersed.

The heat-sensitive multiplex copying sheet of the present invention is used in a state where at least the thermal transfer layer of the upper leaf recording sheet and the thermal transfer receiving layer of the lower leaf recording sheet are set in contact with each other. A heat transfer receiving layer containing a colorant and an adhesive is provided on one surface of the middle leaf base sheet between the and the lower leaf recording sheet, and a leuco dye and a heat-fusible organic compound are contained on the other surface. This includes a set of at least one middle sheet recording sheet provided with a thermal transfer layer.

The leuco dyes contained in the heat-sensitive recording layer and the heat transfer layer include, for example, the following compounds.
3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylamino-2)
-Methylphenyl) -3- (4-dimethylaminophenyl) -6-dimethylaminophthalide, 3-diethylamino-7-dibenzylaminofluoran, 3-cyclohexylamino-6-chlorofluoran, 3-diethylamino-6 -Methyl-7-chlorofluorane, 3-diethylamino-7-chlorofluoran, 3-diethylamino-
7-anilinofluoran, 3- (N-ethyl-N-isoamyl) amino-6-methyl-7-anilinofluoran, 3-diethylamino-7- (m-trifluoromethylanilino) fluoran, 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-diethylamino-7- (o-chloroanilino) fluoran,
3-di (n-butyl) amino-7- (o-chloroanilino) fluoran, 3-di (n-butyl) amino-7-
(O-fluoroanilino) fluoran, 3- (N-ethyl-p-toluidino) -6-methyl-7-anilinofluoran, 3-diethylamino-6-chloro-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, 3,3-bis [1- (4-methoxyphenyl) -1
-(4-pyrrolidinophenyl) ethylene-2-yl]-
4,5,6,7-tetrachlorophthalide, 3,6, -bis (dimethylamino) fluorene-9-spiro-3'-
(6′-dimethylamino) phthalide, 3- (N-ethyl-N-2-tetrahydrofurfurylamino) -6-methyl-7-anilinofluoran, 3- (4-dimethylamino) anilino-5,7 -Dimethyl fluoran, etc.

Of course, it is not limited to these,
If necessary, two or more kinds 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 heat-sensitive recording layer in the heat-sensitive recording layer, and 3 to 50% by weight based on the total solids of the heat-transfer layer in the thermal transfer layer.
% By weight.

The coloring agent contained in the heat-sensitive recording layer includes:
For example, the following compounds may be mentioned. Acid clay, activated clay, attapulgite, zeolite, acidic clays such as bentonite, 4,4′-isopropylidene diphenol, bis (2-tert-butylphenol), 4,4′-
sec-butylidene diphenol, 4-phenylphenol, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 4,4′-cyclohexylidenediphenol, 2,4′-dihydroxydiphenylsulfone,
4,4′-dihydroxydiphenylsulfone, 4-hydroxy-4′-isopropoxydiphenylsulfone, bis (3-allyl-4-hydroxyphenyl) sulfone,
4-hydroxy-4'-methyldiphenyl sulfone, 4
-Hydroxy-4'-benzyloxydiphenylsulfone, 3,4-dihydroxyphenyl-4'-methylphenylsulfone, hydroquinone monobenzyl ether,
-Hydroxybenzophenone, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,4-bis [(4-hydroxyphenyl) isopropylidene] benzene, benzyl 4-hydroxybenzoate, 4-hydroxybenzoic acid -P-methoxybenzyl, phenolic compounds such as novolak-type phenolic resins and phenolic polymers, zinc 4- [2- (p-methoxyphenoxy) ethyloxy] salicylate, 4- [3- (p-tolylsulfonyl) propyloxy] Zinc salicylate, 5- [p- (2
-P-methoxyphenoxyethoxy) cumyl] zinc salt of a salicylic acid derivative such as zinc salicylate, zinc 4-octyloxyacetylaminosalicylate, Np-tolylsulfonyl-N'-phenylurea, 4,4'-bis (p-
Compounds having a sulfamide bond in the molecule, such as (trisulfonylaminocarbonylamino) diphenylmethane

Of course, it is not limited to these,
If necessary, two or more kinds can be used in combination. The amount of the coloring agent used is about 10 to 70% by weight based on the total solid content of the thermosensitive recording layer in the thermosensitive recording layer.

The heat fusible organic compound contained in the thermal transfer layer is not particularly limited as long as it is an organic compound having a melting point of about 35 to 150 ° C., for example, carnauba wax,
Montan wax, paraffin wax, microcrystalline wax, polyethylene wax, palmitic acid, stearic acid, behenic acid, stearic acid amide, ethylenebisstearic acid amide, methyl stearate,
Higher aliphatic compounds such as stearic acid anilide are preferred because of their excellent pressure-sensitive recording properties. The amount of the heat-fusible organic compound used is about 30 to 90% by weight, preferably about 40 to 80% by weight, based on the total solids of the thermal transfer layer.

The heat-sensitive recording layer contains, as an adhesive, an emulsion-polymerized acrylic resin, urethane resin, styrene-butadiene resin, vinyl acetate resin, vinylidene chloride resin, vinyl acetate-vinyl chloride resin, and the like. Hydrophobic resin,
Or completely (partially) saponified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, silicon-modified polyvinyl alcohol, styrene-maleic acid copolymer salt, ethylene-acrylic acid copolymer salt, isobutylene-maleic acid A water-soluble resin such as a salt of a copolymer is contained. The hydrophobic resin is
Usually used in latex form. The content of the adhesive is 5 to 35% by weight based on the total solid content of the heat-sensitive recording layer.
It is about.

Further, if necessary, kaolin, calcium carbonate, amorphous silica, titanium oxide, aluminum hydroxide,
Pigments such as calcined kaolin zinc oxide, stearic acid amide,
m-terphenyl, di-p-methylbenzyl oxalate, di-p-chlorobenzyl oxalate, dibenzyl terephthalate, phenyl 1-hydroxynaphthoate, 1,2-di (3-methylphenoxy) ethane Sensitizers such as 1,1,2-diphenoxyethane, 1-phenoxy-2-naphthoxyethane and p-benzylbiphenyl; 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-
Preservative improvers such as naphthyl-p-phenylenediamine, sodium 2,2'-methylenebis (4,6-di-tert-butylphenyl) phosphate, and fluorescent dyes, coloring dyes, surfactants, water resistance agents, etc. Can also be added.

The heat-sensitive recording layer is generally composed of water as a medium, a leuco dye finely dispersed to have an average particle diameter of about 0.1 to 3 μm, a colorant, an adhesive, and, if necessary, a sensitizer and a storage stability improver. The coating amount after drying the heat-sensitive recording coating liquid obtained by mixing and stirring the mixture on one surface of the upper leaf base sheet is 2 to 7 g /
It is formed by coating and drying so as to have a thickness of about m ² .

Examples of the method of applying the thermal recording coating liquid and the thermal transfer receiving layer coating liquid include an air knife method, a Meyer bar method, a pure blade method, a rod blade method, a reverse roll method, a gravure method, and a slit die method. No.

The thermal transfer layer is generally formed by applying a thermal transfer coating liquid in which a leuco dye is added to a heat-fusible heat-fusible organic compound to the other surface of the upper leaf or middle leaf base sheet at 1 to 8 g / m ^2.
For example, it is formed by applying by a hot melt method so as to have a degree.

The upper, middle and lower leaf base sheets include, for example, high quality papers, films and synthetic papers of about ²⁰ to 70 g / m ² . In particular, for the upper leaf and middle leaf base sheets, glassine paper of about 20 to 40 g / m ² is preferable.

[0025]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but it should be understood that the present invention is by no means restricted thereto. Unless otherwise specified, parts and% in the examples are parts by weight and% by weight, respectively.

Example 1 (1). Preparation of Solution A 10 parts of 3-di (n-butyl) amino-6-methyl-7-anilinofluoran, sulfone-modified polyvinyl alcohol (trade name: Goselan L-3266, Japan) A composition consisting of 5 parts of a 10% aqueous solution of Synthetic Chemical Industry Co., Ltd.) and 25 parts of water was pulverized with a sand mill until the average particle diameter became 0.8 μm to obtain a liquid A.

(2) Preparation of Solution B 10 parts of 4-hydroxy-4'-isopropoxydiphenylsulfone, sulfone-modified polyvinyl alcohol (trade name: Goselan L-3266, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.)
A composition comprising 5 parts of a 10% aqueous solution of water and 25 parts of water was pulverized with a sand mill until the average particle diameter became 1.5 μm to obtain a liquid B.

(3) Preparation of Solution C: 10 parts of m-terphenyl, 5 parts of a 10% aqueous solution of sulfone-modified polyvinyl alcohol (trade name: Goselan L-3266, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) and 25 parts of water The composition was pulverized with a sand mill until the average particle diameter became 1.0 μm to obtain a liquid C.

(4). Preparation of coating solution for heat-sensitive recording layer 40 parts by weight of liquid A, 80 parts by weight of liquid B, 40 parts by weight of liquid C, amorphous silica (trade name: Mizuka Seal P-527, manufactured by Mizusawa Chemical) 15 Parts by weight, 100 parts of a 10% aqueous solution of completely saponified polyvinyl alcohol (trade name: PVA-105, manufactured by Kuraray Co., Ltd.), 2 parts of a 20% aqueous solution of glyoxal, and 30 parts of water are mixed and stirred, and the coating liquid for the heat-sensitive recording layer is mixed I got

(5) Preparation of coating liquid for thermal transfer layer 10 parts of 3-piperidino-6-methyl-7-anilinofluoran, 30 parts of carnauba wax and 15 parts of stearamide were melted at 120 to 130 ° C. Thus, a coating solution for a thermal transfer layer was obtained.

(6) Preparation of Coating Solution for Thermal Transfer Receiving Layer 65 parts of aluminum hydroxide, 20 parts of zinc oxide, 3,5-
A mixed melt of zinc di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (mixed melt weight ratio =
80/20, 25 parts of a 30% aqueous dispersion having an average particle diameter of 2.3 μm), mono (or bis or tris or tetrakis) [poly (0 to 4) [ω-hydro [poly (1 to 7) α]
-Methylbenz] -α-yl] benzyl] zinc salt of salicylic acid (average particle size 2.1 μm) in 30% aqueous dispersion 25
Parts, 50 parts by weight of a 10% aqueous solution of a carboxy-modified polyvinyl alcohol, 10 parts of a 20% aqueous solution of a polyamide epichlorohydrin resin as a waterproofing agent, and a styrene-butadiene resin having a glass transition point of 2 ° C. (solid concentration: 50%) 40 A composition comprising 5 parts by weight, 5 parts of a 20% aqueous solution of sodium polyacrylate and 100 parts of water was mixed and stirred to obtain a coating liquid for a thermal transfer receiving layer.

(7) Preparation of Upper Leaf Recording Sheet On one surface (front side) of 35 g / m ² basis weight and 35 μm thick glassine paper (upper leaf base sheet), a heat-sensitive recording coating solution was dried. After coating and drying so that the coating amount becomes 4.0 g / m ² , a super calender treatment is performed to provide a heat-sensitive recording layer, and a coating liquid for a heat transfer layer having a temperature of 70 to 80 ° C. on the other surface (back surface side). After 3.2 g / m ^{2 was} applied, cooling was performed to form a thermal transfer layer to obtain an upper leaf recording sheet.

(8) Preparation of middle leaf recording sheet After coating a heat transfer receiving layer coating solution on one surface (front side) of a glassine paper (middle leaf base sheet) having a basis weight of 35 g / m ² and a thickness of 35 μm. After coating and drying so that the coating amount becomes 5.4 g / m ² , a heat transfer receiving layer is provided by a super calender treatment, and a temperature of 70 to 80 is applied to the other surface (back surface side).
After applying 3.2 g / m ^{2 of a} coating liquid for a thermal transfer layer at a temperature of ° C., the resultant was cooled to form a thermal transfer layer, thereby obtaining a midleaf recording sheet.

(9). Preparation of lower leaf recording sheet Neutral high-quality paper having a basis weight of 64 g / m ² (lower leaf base sheet)
On one surface (surface side) of the above, a coating solution for the thermal transfer receiving layer was applied and dried so that the coating amount after drying was 5.4 g / m ² to form a thermal transfer receiving layer, and then subjected to a super calender treatment. To obtain a lower leaf recording sheet.

(10). Production of heat-sensitive multiplex copy sheet The back side of the upper leaf recording sheet and the front side of the middle leaf recording sheet, and the back side of the middle leaf recording sheet and the front side of the lower leaf recording sheet cut into A4 size. Were overlapped so as to be in contact with each other to obtain a thermosensitive multiple copy sheet.

Example 2 In the preparation of the coating solution for the thermal transfer receiving layer of Example 1, 3, 5
25 parts of a 30% aqueous dispersion of a mixed melt of zinc di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (melt weight ratio = 80/20, average particle diameter 2.3 μm) 20 parts of toluene, 1 part of diisopropylnaphthalene, 6 parts of zinc 3,5-di (α-methylbenzyl) salicylate and 40 parts of α-methylstyrene-styrene copolymer in 40 parts of a 5% aqueous solution of sulfone-modified polyvinyl alcohol Thermosensitive multiple copying was carried out in the same manner as in Example 1 except that a 1.5 part composition was emulsified and dispersed (average emulsified particle size: 1.8 μm), and then 48.5 parts of a dispersion obtained by degassing toluene was used. I got a sheet.

Example 3 In the preparation of the coating solution for the thermal transfer receiving layer in Example 1, mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α-methyl] Instead of 25 parts of a 30% aqueous dispersion of Benz] -α-yl] benzyl] salicylic acid zinc salt (average particle size 2.1 μm), a 5% aqueous solution of sulfone-modified polyvinyl alcohol 4
20 parts of toluene and 1 part of diisopropylnaphthalene in 0 parts
Part and mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α
-Methylbenz] -α-yl] benzyl] a composition comprising 7.5 parts of zinc salt of salicylic acid was emulsified and dispersed (average emulsified particle diameter: 1.8 μm), and then toluene was degassed.
A thermosensitive multiple copy sheet was obtained in the same manner as in Example 1 except that 8.5 parts were used.

Example 4 A heat-sensitive multiple copy sheet was obtained in the same manner as in Example 1 except that 20 parts of calcium oxide was used instead of 20 parts of zinc oxide in the preparation of the coating solution for the thermal transfer receiving layer of Example 1. Was.

Example 5 In the preparation of the coating solution for the thermal transfer receiving layer of Example 1,
25 parts of a 30% aqueous dispersion of a mixed melt of zinc di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (melt weight ratio = 80/20, average particle diameter 2.3 μm) And mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1
7) Instead of 25 parts of a 30% aqueous dispersion of zinc salt of α-methylbenz] -α-yl] benzyl] salicylic acid (average particle diameter 2.1 μm), 80 parts of a 5% aqueous solution of sulfone-modified polyvinyl alcohol was used. 40 parts of toluene, 7 parts of diisopropylnaphthalene, a mixed melt of zinc 3,5-di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (mixed melt weight ratio = 80/20) 7.5 Part and mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α
-Methylbenz] -α-yl] benzyl] a composition comprising 7.5 parts of zinc salt of salicylic acid was emulsified and dispersed (average emulsified particle diameter: 1.8 μm), and toluene was degassed.
A heat-sensitive multiple copy sheet was obtained in the same manner as in Example 1 except that parts were used.

Comparative Example 1 In the preparation of the coating solution for the thermal transfer receiving layer of Example 1,
25 parts of a 30% aqueous dispersion of a mixed melt of zinc di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (melt weight ratio = 80/20, average particle diameter 2.3 μm) Instead of mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α-methylbenz] -α-yl] benzyl]
A heat-sensitive multiple copy sheet was obtained in the same manner as in Example 1, except that 25 parts of a 30% aqueous dispersion of zinc salicylate (average particle size: 2.1 μm) was used.

Comparative Example 2 In the preparation of the coating solution for the thermal transfer receiving layer of Example 1, mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1-7) α-methyl Benz] -α-yl] benzyl] salicylate zinc salt (average particle size 2.1 μm) instead of 25 parts of a 30% aqueous dispersion, zinc 3,5-di (α-methylbenzyl) salicylate and α-methylstyrene Heat-sensitive multiplexing in the same manner as in Example 1 except that 25 parts of a 30% aqueous dispersion of a mixed melt with a styrene copolymer (mixed melt weight ratio = 80/20, average particle size 2.3 µm) was used. A copy sheet was obtained.

Comparative Example 3 Zinc 3,5-di (α-methylbenzyl) salicylate and α
30% of a mixed melt with a methylstyrene / styrene copolymer (mixed melt weight ratio = 80/20, average particle size 2.3 μm)
Bis (3-allyl-4-hydroxyphenyl) sulfone (average particle diameter 2.1 μm) instead of 25 parts of the aqueous dispersion
Example 1 except for using 25 parts of a 30% aqueous dispersion of
In the same manner as in Example 1 to obtain a thermosensitive multiple copy sheet.

Comparative Example 4 In the preparation of the coating solution for the thermal transfer receiving layer of Example 1, 3, 5
25 parts of a 30% aqueous dispersion of a mixed melt of zinc di (α-methylbenzyl) salicylate and an α-methylstyrene / styrene copolymer (melt weight ratio = 80/20, average particle diameter 2.3 μm) And mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1
7) Instead of 25 parts of a 30% aqueous dispersion of α-methylbenz] -α-yl] benzyl] salicylic acid zinc salt (average particle size 2.1 μm), zinc 4-octyloxyacetylaminosalicylate (average particle size) A heat-sensitive multiplex copy sheet was obtained in the same manner as in Example 1 except that 50 parts of a 30% aqueous dispersion (2.1 μm) was used.

The following evaluation test was carried out on the thus obtained heat-sensitive multiplex copy sheet, and the obtained results are shown in Table 1.

[Heat Sensitive Recording Property] Thermal Sensitivity Evaluation Machine [Product name: TH
-PMD, manufactured by Okura Electric Co., Ltd.].
Record each multiple thermal copy sheet at 45mJ / dot,
The recording density of the obtained recording image was measured using a Macbeth densitometer [RD-9
14 type, manufactured by Macbeth Co., Ltd.] in the visual mode.

[Pressure Sensitive Recording Property] Typewriter [Product name:
elctric65, manufactured by OLYMPIA], and the recording density of the recorded image transferred to the thermal transfer receiving layer of the lower leaf recording sheet was measured in visual mode with a Macbeth densitometer (RD-914, manufactured by Macbeth). .

[0047]

[Table 1]

[0048]

As shown in Table 1, the multiple thermographic copying sheet of the present invention has excellent effects in thermal recording and pressure-sensitive recording.

Claims (3)

[Claims] 1. A heat-sensitive recording layer containing a leuco dye and a colorant is provided on at least one surface of an upper leaf base sheet, and a thermal transfer layer containing a leuco dye and a heat-fusible organic compound is provided on the other surface. In the heat-sensitive multiplex copying sheet having an upper leaf recording sheet and a lower leaf recording sheet provided with a thermal transfer receiving layer containing a colorant and an adhesive on one surface of the lower leaf base sheet, the color is formed in the thermal transfer receiving layer. As an agent, mono (or bis or tris or tetrakis) [poly (0 to 4) [ω-
Hydro [poly (1-7) α-methylbenz] -α-yl] benzyl] zinc salicylate and 3,5-di (α-
(Methylbenzyl) heat-sensitive multiple copy sheet containing zinc salicylate. 2. An emulsified mono (or bis or tris or tetrakis) [poly (0-4) [ω-hydro [poly (1) 7) The heat-sensitive multi-copy sheet according to claim 1, wherein at least one of zinc α-methylbenz] -α-yl] benzyl] salicylate and zinc 3,5-di (α-methylbenzyl) salicylate is contained. 3. The heat-sensitive multiplex copying sheet according to claim 1, wherein zinc oxide is further contained in the thermal transfer receiving layer.