JP4454639B2 - A thermal recording paper capable of color recording of two colors with a single thermal head and a recording method using the same. - Google Patents

Description

  The present invention relates to a heat-sensitive recording paper capable of color recording of two colors with a thermal head capable of generating a single amount of heat, and a recording method using the same.

  A thermal recording paper in which two sheets of upper and lower sheets are combined is known. When heat is applied from the upper part of the upper paper sheet by the thermal head, information is recorded on the upper paper sheet surface, and at the same time, heat is transmitted to the lower paper sheet and the same information is recorded on the lower paper sheet surface. In such a thermal recording paper in which an upper sheet and a lower sheet are combined, there is a demand for the recording portion of the lower sheet to have two colors. For example, if there is a black colored area and a red colored area, it has the meaning of attracting attention to the red part with black and red coloring contrast or clarifying that the information to be described is different. .

  On the other hand, in order to develop such two colors, the heat-sensitive color-developing layer of the lower leaf paper is divided into regions by forming, for example, a heat-sensitive color-developing layer portion that develops black color and a heat-sensitive color-developing layer portion that develops red color. If they are formed, each color is developed in each part. However, it is complicated to form the thermosensitive coloring layer by dividing the region, and at the same time, there is a process inconvenience that the same coating process must be performed twice.

  On the other hand, there is a method of forming two colors by forming a heat-sensitive recording layer so that each color is developed at different temperatures and changing the amount of heat applied from the thermal head. In this case, since the coating of the thermosensitive coloring layer is one layer, there is no problem with the application of the thermosensitive coloring layer, but the thermal head generates two types of heat, and the mechanical complexity of the thermal head is reduced. At the same time, costs increase. If such a special thermal head is not provided, it is meaningless even if a two-color coloring layer is present.

  The present invention provides a thermal recording paper capable of easily producing two colors using a single heat quantity thermal head and a thermal recording method using the thermal recording paper.

  That is, the present invention relates to a thermal recording paper in which an upper sheet and a lower sheet are combined and color is recorded by applying heat from the upper surface, and the upper surface of the upper sheet is developed with a leuco dye and a developer. And a black leuco dye is applied only to a portion of the lower leaf sheet that needs to be black-colored on the lower surface that is in contact with the lower leaf sheet of the upper leaf sheet. The upper surface has a two-color recording with a single calorie thermal head characterized in that a thermal coloring layer containing a developer and a leuco dye of a color other than black is formed on the entire surface where recording is required. Provide thermal recording paper that can

  Further, in the present invention, when recording on a thermal recording paper using a thermal head that generates a single calorie, the thermal recording paper is a combination of an upper sheet and a lower sheet, and both apply heat from the upper surface. A heat-sensitive recording paper that records and develops a color by having a heat-sensitive recording layer containing a leuco dye and a developer on the upper surface of the upper paper, and on the lower surface in contact with the lower paper of the upper paper The black leuco dye is applied only to the portion of the lower leaf paper that requires black color development, and the upper surface of the lower leaf paper has a developer and a leuco dye of a color other than black on the entire portion that requires recording. Even a single heat quantity thermal head characterized in that a black recording portion and a recording portion of a color other than black are formed on the lower leaf paper by using a layer having a thermosensitive coloring layer containing Provided is a recording method that enables color development recording.

  According to the present invention, in the thermal recording paper having the upper and lower sheets, a thermal coloring layer containing a developer and a leuco dye of a color other than black is formed on the upper surface of the lower sheet. A black leuco dye is applied only to a portion where black color development is required on the lower surface in contact with the lower leaf paper of the leaf paper. As a result, the manufacturing method itself is the entire surface application for the lower leaf paper, and no difficult technique is produced. In addition, the lower surface of the upper paper sheet is not so difficult because it is a single color application that does not require positioning. Further, according to the present invention, when heat is applied from the upper leaf paper with a single heat quantity thermal head, only different colors are developed in different regions on the lower leaf paper side. Color development recording is possible.

The present invention will be described in more detail with reference to the drawings.
FIG. 1 is a cross-sectional view schematically illustrating the heat-sensitive recording paper of the present invention.
FIG. 2 is a cross-sectional view schematically showing the black color development state of the thermal recording paper of the present invention.
FIG. 3 is a cross-sectional view schematically showing the color of the heat-sensitive recording paper of the present invention in a color other than black (particularly red).

  In FIG. 1, an upper sheet 1 and a lower sheet 2 exist, and a normal heat-sensitive recording layer 3 exists on the surface of the upper sheet 1. Further, a thermal head 4 is present thereon, and the heat-sensitive recording layer 3 is colored by application of heat from the thermal head 4.

  In the present invention, a black leuco dye (indicated by ◯ in the figure) 5 is applied to the lower surface in contact with the lower leaf paper 2 of the upper leaf paper 1 at the portion corresponding to the portion that requires black color development. The upper surface of the lower leaf paper 2 includes a color developer 6 represented by a square (□) and a leuco dye 7 of a color other than black represented by a triangle (Δ) (hereinafter red is taken as an example in this figure). Layer 8 is applied. Although it is limited to other than black, even if black or other color leuco dyes are mixed, if there is no color generated with a specific amount of heat emitted from the thermal head 4, there will be no problem with the color development of the present invention. do not do.

  In the present invention, as shown in FIG. 2, the thermal head 4 is in the black color development region, and when heat is applied, the black leuco dye is transferred to the heat sensitive layer on the lower leaf paper surface, and into the heat sensitive layer on the lower leaf paper surface. The developer and black leuco dye 5 react to produce black color. Of course, in the thermosensitive coloring layer present on the upper surface of the lower leaf paper 2, the red leuco dye 7 and the developer 6 should also react and the red coloring should occur at the same time, but the black color has a high density. Black is present as the color hue.

  Next, when the thermal head is in a portion where there is no black leuco dye, and heat is applied, the red leuco dye 7 and the developer 6 of the color developing layer 8 existing on the surface of the lower leaf paper 2 react to react with the red color. Is formed. As a result, a black coloring portion and a red coloring portion are present.

  As shown in FIG. 1, a wax layer 10 may be formed in a portion that develops red color. When the wax layer 10 is present, the wax layer moves to the heat-sensitive layer on the lower leaf paper when heat is applied, the color development temperature of the heat-sensitive color development layer decreases, and red color development occurs more vividly. The wax layer 10 is formed as a separate layer from the black leuco dye 5 in FIG. 1, but this is one embodiment, and if necessary, a wax layer is first formed on the entire lower surface of the upper leaf paper, Then, a two-layer structure in which a black leuco dye is applied only to a portion where black is required may be employed.

Examples of leuco dyes contained in the leuco dye thermal recording layer and the thermal transfer layer include the following.

3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylamino-2-methylphenyl) -3- (4-dimethylaminophenyl) -6-dimethylaminophthalide, 3-diethylamino-7-dibenzylaminofluorane, 3-cyclohexylamino-6-chlorofluorane, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-7-chlorofluorane, 3-diethiamino -7-anilinofluorane, 3- (N-ethyl-N-isoamyl) amino-6-methyl-7-anilinofluorane, 3-diethylamino-7- (m-trifluoromethylanilino) fluorane, 3 -(N-methyl-N-cyclohexyl) amino-6-methyl-7-anilinofluorane, 3-diethylamino No-6-methyl-7-anilinofluorane, 3-di (n-butyl) amino-6-methyl-7-anilinofluorane, 3-di (n-pentyl) amino-6-methyl-7- Anilinofluorane, 3-diethylamino-7- (o-chloroanilino) fluorane, 3-di (n-butyl) amino-7- (o-chloroanilino) fluorane, 3-di (n-butyl) amino-7- ( o-fluoroanilino) fluorane, 3- (N-ethyl-p-toluidino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3-piperidino- 6-Methyl-7-anilinofluorane, 3,3-bis [1- (4-methoxyphenyl) -1- (4-dimethylaminophenyl) ethylene-2-yl] -4,5,6,7- Tetrachlorofu Talide, 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-anilinofluorane , 3- (4-Dimethylamino) anilino-5,7-dimethylfluorane, etc. Of course, it is not limited to these, and two or more kinds can be used in combination as required.

  The amount of the leuco dye used is about 5 to 35% by weight, preferably about 5 to 20% by weight, based on the total solid content of the heat sensitive recording layer in the heat sensitive recording layer.

Examples of the developer contained in the developer heat-sensitive recording layer include the following compounds.

  Acid clays such as acid clay, activated clay, attapulgite, zeolite, bentonite and the like, 4,4′-isopropylidene diphenol, 4,4′-cyclohexylidene diphenol, 2,4′-dihydroxydiphenyl sulfone, 4,4 '-Dihydroxydiphenylsulfone, 4-hydroxy-4'-isopropoxydiphenylsulfone, bis (3-allyl-4-hydroxyphenyl) sulfone, 4-hydroxy-4'-methyldiphenylsulfone, 4-hydroxy-4'-benzyl Oxydiphenylsulfone, 3,4-dihydroxyphenyl-4′-methylphenylsulfone, hydroquinone monobenzyl ether, 4-hydroxybenzophenone, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,4-bis [(4-hydroxyphenyl) isop Pyridene] benzene, 4-hydroxybenzoic acid benzyl, novolac type phenolic resin, phenolic compounds such as phenol polymer, 4- [2- (p-methoxyphenoxy) ethyloxy] salicylic acid zinc, 4- [3- (p-tolyl) Sulfonyl) propyloxy] zinc salicylate, 5- [p- (2-p-methoxyphenoxyethoxy) cumyl] zinc salicylate, zinc 4-octyloxyacetylaminosalicylate, mono (or bis or tris or tetrakis) [poly (0 4) Zinc salts of salicylic acid derivatives such as [ω-hydro [poly (1-7) α-methylbenz] -α-yl] benzyl] zinc salicylate, zinc 3,5-di (α-methylbenzyl) salicylate, N— p-tritylsulfonyl-N'-phenylurea, 4,4'-bis (p-tolylsulfur Compounds having a sulfonamide bond in the molecule, such as a sulfonyl amino carbonyl amino) diphenylmethane, may of course, not limited to, addition be used in combination of two or more as necessary.

  The amount of the developer used is about 10 to 50% by weight, preferably about 15 to 40% by weight, based on the total solid content of the heat-sensitive recording layer.

  In particular, the zinc salt of the salicylic acid derivative is particularly preferable for the thermal transfer receiving layer because it is excellent in thermal recording property and pressure sensitive recording property.

The heat-fusible organic compound thermal transfer layer may contain a heat-fusible organic compound (wax). As the heat fusible organic compound, an organic compound having a melting point of about 60 to 150 ° C., preferably about 65 to 140 ° C. can be used. Specific examples of the thermofusible organic compound contained in the thermal transfer layer of the present invention include diphenoxyethane, naphthyl benzyl ether, oxalic acid di-p-methylbenzyl ester, oxalic acid dibenzyl ester, m-tert-phenyl. Aromatic compounds such as carnauba wax, montan wax, paraffin wax, microcrystalline wax, polyethylene wax, palmitic acid, stearic acid, behenic acid, stearamide, ethylenebis stearamide, methyl stearate, stearic acid anilide, etc. Of higher aliphatic compounds. Of these, higher aliphatic compounds are preferred because of their excellent pressure-sensitive recording properties. These can be used alone or in combination of two or more.

  The amount of the heat fusible organic compound used is about 50 to 97% by weight, preferably about 40 to 80% by weight, based on the total solid content of the thermal transfer layer.

Thermal recording layer

The heat-sensitive recording layer is generally an auxiliary medium such as a leuco dye, a developer, an adhesive, and, if necessary, a sensitizer and a shelf life improver, which are finely dispersed in water with a mean particle size of about 0.1 to 3 μm. The coating amount for the heat-sensitive recording layer obtained by mixing and stirring the agent on the front surface of the upper leaf base sheet or the front surface of the middle leaf recording sheet is about ² to 7 g / m ² after drying, preferably Is formed by coating and drying so as to be about 3 to 6 g / m ² .

  The use ratio of the leuco dye and the developer is about 50 to 500 parts by weight, preferably about 100 to 300 parts by weight, with respect to 100 parts by weight of the leuco dye, but is limited to this range. It is not a thing. The amount of adhesive used may be about 10 to 35 parts by weight with respect to 100 parts by weight of the thermosensitive recording layer.

  Examples of the adhesive include methyl cellulose, methoxy cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, cellulose, fully (partially) saponified polyvinyl alcohol, acetoacetyl-modified polyvinyl alcohol, silicon-modified polyvinyl alcohol, carboxy-modified polyvinyl alcohol, and sulfone-modified. Water-soluble adhesive such as polyvinyl alcohol, starch and derivatives thereof, casein, gelatin, alkali salt of styrene / maleic anhydride copolymer, alkali salt of iso (or diiso) butylene / maleic anhydride copolymer, or acrylic Examples thereof include water-dispersible adhesives such as latex, urethane-based latex, and styrene / butadiene-based latex.

  Examples of auxiliary agents include kaolin, calcium carbonate, amorphous silica, titanium oxide, aluminum hydroxide, calcined kaolin, zinc oxide and other pigments, m-terphenyl, oxalic acid di-p-methylbenzyl ester, and oxalic acid dioxalate. -P-chlorobenzyl ester, terephthalic acid dibenzyl ester, 1-hydroxynaphthoic acid phenyl ester, 1,2-di- (3-methylphenoxy) ethane, 1,2-diphenoxyethane, 1-phenoxy-2-naphthoxyethane , Sensitizers such as p-benzylbiphenyl, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, N, N′-di-2-naphthyl-p-phenylene Preservatives such as diamine, 2,2′-methylenebis (4,6-di-tert-butylphenyl) sodium phosphate, carnauba wax, Waxes such as tantalum wax, paraffin wax, microcrystalline wax, polyethylene wax, higher aliphatic amides such as stearic acid amide and ethylenebisstearic acid amide, lubricants such as zinc stearate and calcium stearate, fluorescent dyes, colored dyes, interfaces An activator, a waterproofing agent, etc. can also be added.

  After forming each coating agent, the thermal recording paper of this invention is obtained by apply | coating with a predetermined coating applicator.

  The present invention will be described in further detail with reference to examples. The present invention should not be construed as being limited to these examples.

Example 1
By mixing the following formulation, a composition for a heat-sensitive color forming layer formed on the upper surface of the upper leaf paper is formed and applied at an application amount of 5 to 10 g / m ² using an air knife coater.
Ingredient Weight part leuco dye (Yamamoto Kasei Co., Ltd. commercial product ODB-2) 10
Developer (commercial product D8, Nippon Soda Co., Ltd.) 20
Sensitizer (Dainippon Ink Chemical Co., Ltd., commercial product HS2048) 20
Water 50

Formation of black leuco dye ink An ink having the following formulation is formed and applied to the black color development area on the lower surface of the upper paper sheet. The coating amount was 6 g / m ² .
Ingredient Weight parts Behenic acid 40-50
Paraffin wax 10
Montan Wax 40
Leuco dye (Yamamoto Kasei Black 15) 5-10
Carnauba wax 5

Red coloring layer By mixing the following formulation, a red coloring thermal coloring ink was formed, and this was applied to the upper surface of the lower leaf paper at a coating amount of 3.0 g / m ² .
Ingredient Weight part leuco dye (Hodogaya Chemical Co., Ltd. commercial product Red DCF) 10
Developer (commercial product D8, Nippon Soda Co., Ltd.) 20
Sensitizer (Dainippon Ink Chemical Co., Ltd., commercial product HS2048) 20
Water 50

  The obtained upper sheet and lower sheet were overlapped so that the black color layer on the lower surface of the upper sheet and the heat-sensitive color layer of the lower sheet face each other to obtain the heat-sensitive color paper of the present invention.

  This was used to fill a thermal recording apparatus having a thermal head having a single calorific value, and predetermined information was printed by applying the calorific value. As a result, a black and red coloring layer in a predetermined region was clearly formed.

Sectional drawing which illustrates typically the thermal recording paper of this invention. Sectional drawing which shows typically the state of the black color development of the thermosensitive recording paper of this invention. Sectional drawing which shows typically the color development state of colors (red) other than black of the thermal recording paper of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Upper leaf paper, 2 ... Lower leaf paper, 3 ... Thermosensitive coloring layer, 4 ... Single heat amount thermal head, 5 ... Black leuco dye layer, 6 ... Developer, 7 ... Non-black leuco dye (for example, Red), 8 ... thermosensitive coloring layer, 10 ... wax layer.

Claims (4)

In the thermal recording paper in which the upper leaf paper and the lower leaf paper are combined and both color and record by applying heat from the upper surface,
The upper surface of the upper leaf paper has a thermosensitive recording layer containing a leuco dye and a color developer, the lower lobe sheet on a lower surface in contact with the lower lobes paper upper-fed black coloring recording portion of the required Black leuco dye is applied only to a part ,
On the upper surface of the lower leaf paper, a thermosensitive coloring layer containing a developer and a leuco dye of a color other than black is formed on the entire surface where recording is required,
A heat-sensitive recording capable of two-color recording with a single-heat amount thermal head, wherein a wax that dissolves at a recording temperature is applied to a portion of the lower surface of the upper leaf paper that is not coated with a black leuco dye. paper.   2. The heat-sensitive recording paper capable of two-color color recording according to claim 1, wherein the heat-sensitive color developing layer formed on the upper surface of the lower leaf paper is a red color developing layer. When recording on a thermal recording paper using a thermal head that generates a single amount of heat, the thermal recording paper is colored by applying heat from the top surface in combination with the upper and lower sheets. Thermal recording paper to record,
Has a heat-sensitive recording layer comprising the upper surface of the upper leaf paper and leuco dye and the developer, a black color under-fed to the lower surface in contact with the lower leaves paper of the upper leaf paper recording portion of the required Black leuco dye is applied only to a part ,
On the upper surface of the lower leaf paper, a thermosensitive coloring layer containing a developer and a leuco dye of a color other than black is formed on the entire surface where recording is required,
By using a portion of the lower surface of the upper leaf paper that is not coated with the black leuco dye, a wax that dissolves at the recording temperature is used, so that the lower leaf paper has a black recording portion and a recording portion of a color other than black. A recording method which enables two-color color recording even with a single heat quantity thermal head.   4. A recording method for enabling two-color color recording even with a single heat quantity thermal head according to claim 3, wherein the heat-sensitive color developing layer formed on the upper surface of the lower leaf paper is a red color developing layer.

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