JP2947975B2 - Thermal transfer recording medium - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer recording medium. More specifically, the present invention relates to a thermal transfer recording medium which is excellent in thermal transferability and storage stability and can be printed many times.

[0002]

2. Description of the Related Art Thermal transfer recording media disclosed in the prior art include, for example, JP-A-55-105.
579 and JP-A-63-268693 disclose a technique in which a fine porous layer is formed and the layer is impregnated with a thermal transfer ink. Japanese Patent Laid-Open No. 57-160
No. 691 discloses a technique of forming a network structure using organic or inorganic fine powder and impregnating with a thermal transfer ink. Also, JP-A-57-185192 discloses that
A technique of impregnating porous paper with a thermal transfer ink has been disclosed. The above-mentioned known technology discloses a technology relating mainly to a support structure of a thermal transfer recording medium for printing many times. On the other hand, in the prior art focusing on the heat transferable ink layer for the purpose of increasing the printing resolution of the thermal transfer recording medium, for example, Japanese Patent Application Laid-Open No. Sho 60-94388 discloses that a thermoplastic fatty acid amide is used as a solid component as a heat transferable ink. Japanese Patent Application Laid-Open (JP-A) No. 60-236793 describes, as a heat transferable ink, a thermoplastic low molecular weight polyethylene wax or montan wax as a solid component as a heat transferable ink. Further, in a known document relating to a large number of thermal transfer recording media represented by JP-A-61-51386, carnauba wax, which is a natural plant-based wax, is disclosed as a main component of a binder component of a thermal transfer ink.

[0003]

In recent years, with the rapid development of the information industry, the role played by thermal transfer recording media has become more and more important. There is an entity in which the center of the binder component is mainly carnauba wax.
That is, carnauba wax has a melting point of 81 to 86 ° C,
Demonstrate excellent thermal transfer printability and storage stability,
It can be said that it is a main material of the thermal transfer ink binder component in the thermal transfer recording medium because excellent print durability after printing is obtained. In addition, carnauba wax is hard as its own property and has properties such as good gloss, so that it is used in glazing wax for furniture, automotive wax, hot melt adhesive, etc. There is a major problem with availability. That is,
Carnauba wax is a natural wax, and there is a problem that the supply amount in the market is limited, and there is a problem such as a shortage of the supply amount and a variation in quality for a thermal transfer recording medium that is increasingly used. Therefore, in the heat-sensitive transfer recording medium market, the emergence of an alternative wax instead of carnauba wax is eagerly desired.

[0004] In view of the above prior art, the present invention has as its main object to determine whether an excellent thermal transfer recording medium can be obtained by not using carnauba wax as a binder component for a thermal transfer ink at all or by using a very small amount thereof in combination. There is a novel thermal transfer ink component capable of exhibiting substantially the same properties as conventionally known thermal transfer inks mainly composed of carnauba wax, and excellent thermal transfer properties using the novel thermal transfer ink component (high It is an object of the present invention to provide a heat-sensitive transfer recording medium which is excellent in density and resolution) and excellent in storage stability and can be printed many times as required.

[0005]

That is, the present invention is as follows. (A) forming a thermal transfer ink layer on a support,
The thermal transfer recording medium is characterized in that the thermal transfer ink layer contains a colorant and a solid component at normal temperature. [Wherein, A represents an isocyanuric group (residue of hydrogen substituted with isocyanuric acid), X represents an alkylene group or an alkenyl group represented by an integer having 2 to 5 carbon atoms;
Represents -X-OOCR ₃ or -X-OH group. R ₁ , R ₂ and R ₃ each represent a higher alkyl group or an alkenyl group represented by an integer having 12 to 30 carbon atoms. A crystalline wax selected from the group of isocyanuric acid esters represented by the formula
A heat-sensitive transfer recording medium characterized in that it is contained in a range of weight%. (B) In a thermal transfer recording medium having one or more thermal transfer ink layers formed on a support via an adhesive layer, any one or all of the thermal transfer ink layers may be
It contains a colorant and a solid component having a Shore D hardness of 45 or more at room temperature, and the solid component has the general formula (1)
Is a crystalline wax selected from the group of isocyanuric acid esters represented by
A thermal transfer recording medium characterized by being contained in an amount of 5% by weight. (C) In a thermal transfer recording medium in which a thermal transferable ink layer is formed on a support exhibiting microporous properties, the thermal transferable ink layer has a hardness of 4 at Shore D at room temperature and a colorant.
5 or more, wherein the solid component is a mixture of one or more crystalline waxes selected from the group of isocyanuric acid esters represented by the general formula (1). A thermal transfer recording medium characterized by being contained in a range of 95% by weight. (D) The heat-sensitive transfer recording medium according to any one of (a) to (c), wherein the crystalline wax has a melting point in the range of 65 to 95 ° C. (E) The crystalline wax is tris (2-hydroxyethyl) isocyanurate adduct of 2 or 3 stearic acid, tris (2-hydroxyethyl) isocyanurate adduct of 2 or 3 palmitic acid, tris (2-hydroxyethyl) ) 2 or 3 myristic acid adduct of isocyanurate, 2 or 3 behenic acid adduct of tris (2-hydroxyethyl) isocyanurate, 2 or 3 stearic acid adduct of tris (2-hydroxypropyl) isocyanurate, tris ( 2- or 3-palmitic acid adduct of 2-hydroxypropyl) isocyanurate, 2- or 3-myristic acid adduct of tris (2-hydroxypropyl) isocyanurate, 2- or 3-behenic acid addition of tris (2-hydroxypropyl) isocyanurate It is characterized by being a thing Any thermal transfer recording medium of the (a) to (d) that. (F) The solid component is characterized in that the crystalline wax is used in combination with at most 30% by weight of the following component (B) and / or at most 15% by weight of component (C). (A) The thermal transfer recording material of any of (e). (B) Animal wax, plant wax, mineral wax, petroleum wax, synthetic paraffin wax, fatty acid amide wax, modified wax oxidized or acid-modified, the following general formula (2): R ₄ COO- (ZO) ) N-OC-R-CO- (O-Z) n-Q (2) [wherein, R represents a phenylene group, and Z has 2 carbon atoms.
Represents an alkylene group of 5 to 5, and Q is -OOCR ₅ or-
Represents an OH group. R ₄ and R ₅ each have a carbon number of 12 to
30 represents a higher alkyl group or an alkenyl group, and n represents an integer of 1 to 50. One or more selected from the group of crystalline waxes of terephthalic acid esters represented by the formula:
A mixture of more than one species. (C) an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 28% by weight or less, an ethylene-ethyl acrylate copolymer resin having ethyl acrylate of 35% by weight or less,
Ethylene-methyl acrylate copolymer resin containing 35% by weight or less of methyl acrylate, crystalline saturated polyester resin, ethylene-acrylic acid copolymer resin, ethylene-methacrylic acid copolymer resin, styrene-ethylene-butylene-styrene block copolymer resin , Styrene-ethylene-
Propylene-styrene block copolymer resin, styrene-
Butadiene-styrene block copolymer resin, styrene-
One or a mixture of two or more heat-fusible resin materials selected from styrene block copolymer resins such as isoprene-styrene block copolymer resins.

Hereinafter, the present invention will be described in more detail. As described above, the thermal transfer recording medium of the present invention is formed by forming a thermal transferable ink layer shown below on a support shown below, and the thermal transferable ink layer is formed of a colorant and preferably Shore D at room temperature. Is a heat-sensitive transfer recording medium containing a solid component having a hardness of 45 or more. As the support used in the thermal transfer recording medium of the present invention,
As one of them, a material which is rich in thermal rigidity (heat resistance strength), dimensional stability and surface smoothness may be used. As another type, there is no problem even if it is a porous sheet-like support such as paper or fiber. Generally, the support generally has the following properties. One of them is that, as heat resistance, it has both toughness and dimensional stability that does not soften or plasticize depending on the heating temperature of a heat source such as a thermal head. The second is the property that the thermal transferable ink layer containing the thermal transferable substance on the support has sufficient smoothness to exhibit a good thermal transfer rate (high print density and high resolution). Can be

Examples of such paper include paper such as plain paper, condenser paper, laminated paper, and coated paper; resin films such as polyethylene, polyethylene terephthalate, polyester, polystyrene, polypropylene, polycarbonate resin, polyamide, and polyimide; and paper. -A resin film composite, a metal film such as an aluminum foil, and a metal foil such as an aluminum-a resin film composite, a paper-a metal composite such as aluminum, a paper-metal foil-a resin film composite, and the like can be suitably used. In addition, the surface of the support that is in direct contact with the thermal head is provided with a heat-resistant protective layer such as silicone resin, fluorine resin, polyimide resin, polycarbonate resin, phenol resin, melamine resin, nitrocellulose, etc. May be adopted. The thickness of the support is not particularly limited, but generally 60 μm or less by obtaining good thermal conductivity.
Preferably 30μ or less, particularly preferably 2μ to 20μ
Is preferred. That is, the support used in the heat-sensitive transfer recording material of the present invention is not particularly limited with respect to the configuration of the back surface side of the support, and may be arbitrary. For example, a general material such as an anti-blocking layer and an anti-sticking layer may be used. A support having a suitable backing layer may be used. The reason why the thermal transfer recording material of the present invention is preferably a thermal transfer recording material using the following thermal transfer ink component comprising one or a plurality of thermal transfer ink layers on a support via an adhesive layer, This is because it is recommended as an excellent thermal transfer recording medium that can be printed once, and there is no particular limitation. Preferably, when two or more thermal transfer ink layers are formed, the uppermost layer increases thermal transferability ( It is preferable that the melting temperature is lower than that of the lower layer or that the melt viscosity is lower than that of the lower layer. The reason why the heat-sensitive transfer recording medium of the present invention is also preferably a heat-sensitive transfer recording medium using the following heat-transferable ink component obtained by forming a heat-transferable ink layer on a support exhibiting microporous properties, This is because it is also recommended as an excellent thermal transfer recording medium that can be printed many times, and as the support exhibiting such microporous properties, a known support may be used, and there is no particular limitation. It is preferable that a porous support is selected from the above-mentioned supports according to the purpose.

In the above-mentioned thermal transfer recording medium, each layer of the adhesive layer and one or more thermal transfer ink layers composed of a plurality of layers may be layers each having a desired function. In the thermal transfer recording medium of the present invention, the thermal transferable ink layer is at least one of the transfer layers.
5 to 95% by weight of a layer or a mixture of two or more crystalline waxes selected from the group of the isocyanuric esters represented by the general formula (1) above, It is important that the content is within the range in order to achieve the object of the present invention. Examples of such a compound include tris (2-hydroxyethyl) isocyanurate, which is an ethylene oxide adduct of isocyanuric acid, and tris (2-hydroxyethyl) isocyanurate, isocyanuric acid.
Generic term tris (2-hydroxyalkyl) isocyanate represented by tris (2-hydroxypropyl) isocyanurate which is an adduct of propylene oxide, tris (2-hydroxybutyl) isocyanurate which is an adduct of 3-butylene oxide of isocyanuric acid, and the like Representative products obtained by subjecting the following fatty acids and / or their acid anhydrides and / or their lower alkyl esterified fatty acid derivatives to an esterification reaction or a transesterification reaction (de-alcoholization ester reaction) to the active hydroxyl group of the nurate are representative. As an example. It is most preferable to use tris (2-hydroxyethyl) isocyanurate and / or tris (2-hydroxypropyl) isocyanurate as a starting material as the method for synthesizing the crystalline esterified wax having an isocyanuric acid skeleton of the present invention.

In the present invention, in the following description, fatty acids and / or their acid anhydrides and / or their lower alkyl esterified fatty acid derivatives are collectively referred to simply as fatty acids. That is, the generically referred to fatty acids are saturated fatty acids or unsaturated fatty acids represented by an integer of 12 to 30 carbon atoms, and specific examples thereof include the following. Such compounds include, for example, lauric acid, myristic acid, palmitic acid, stearic acid, tridecanoic acid, nonadecanoic acid, behenic acid, oleic acid, heptadecanoic acid, norbornic acid, tetracosanoic acid, tricosanoic acid, hexacosanoic acid, heptacosanoic acid And fatty acids such as octacosanoic acid and their acid anhydrides or their lower alkyl esterified fatty acid derivatives. The expression "lower alkyl" specifically refers to an alkyl group represented by an integer having 5 or less carbon atoms, other halogenated alkyl groups, phenyl groups, naphthyl groups and the like. In the present invention, as the crystalline esterified wax having an isocyanuric acid skeleton in the above description, 2 or 3 stearic acid adduct of tris (2-hydroxyethyl) isocyanurate and tris (2-hydroxyethyl) isocyanurate may be used. 2 or 3 palmitic acid adduct, 2 or 3 myristic acid adduct of tris (2-hydroxyethyl) isocyanurate, 2 or 3 behenic acid adduct of tris (2-hydroxyethyl) isocyanurate, tris (2-
2- or 3-stearic acid adduct of (hydroxypropyl) isocyanurate, tris (2-hydroxypropyl)
2 or 3 palmitic acid adduct of isocyanurate, 2 of tris (2-hydroxypropyl) isocyanurate
Or 3 myristic acid adduct, 2 or 3 behenic acid adduct of tris (2-hydroxypropyl) isocyanurate is particularly recommended. The terephthalic acid skeleton crystalline esterified wax represented by the general formula (2) according to the present invention is typically obtained by the following method.

As such a compound, for example, bis (2) which is a 2-ethylene oxide adduct of terephthalic acid is used.
Bis (2-hydroxypropyl) terephthalate, which is a 2-propylene oxide adduct of terephthalic acid and terephthalic acid;
Bis (2-hydroxybutyl) terephthalate, a butylene oxide adduct
A typical example is a product obtained by subjecting the above fatty acid to an esterification reaction or a transesterification reaction (dealcoholization ester reaction) with respect to the active hydroxyl group of (hydroxyalkyl) terephthalate. Preferably, bis (2-hydroxyethyl) terephthalate and / or bis (2-hydroxypropyl) terephthalate is most preferably used as a starting material as the method for synthesizing the crystalline esterified wax having a terephthalic acid skeleton of the present invention. Specifically, bis (2-hydroxyethyl) terephthalate adduct of 1 or 2 stearic acid, bis (2
-Hydroxyethyl) terephthalate adduct of 1 or 2 palmitic acid, bis (2-hydroxyethyl) terephthalate adduct of 1 or 2 myristic acid, bis (2-
1- or 2-behenic acid adduct of hydroxyethyl) terephthalate, 1 or 2 stearic acid adduct of bis (2-hydroxypropyl) terephthalate, 1 or 2 palmitic acid adduct of bis (2-hydroxypropyl) terephthalate, bis (2 -Hydroxypropyl) terephthalate 1 or 2 myristic acid adduct, bis (2-
Hydroxypropyl) terephthalate adducts of 1 or 2 behenic acid and the like are preferred.

In the present invention, a heat transferable ink mainly comprising the crystalline esterified wax having an isocyanurate skeleton is preferred. The reason is that wax hardness is relatively high at room temperature. In addition, the property as a thermal transferable ink can achieve a Shore D hardness of 45 or more and exhibit extremely sharp melting point behavior. Furthermore, it is possible to achieve properties in which the melt viscosity and melting point of the material alone are close to those of carnauba wax. In general, the properties as a thermal transfer ink can achieve a Shore D hardness of 45 or more and exhibit extremely sharp melting point behavior.Furthermore, the melt viscosity and melting point of wax alone show properties close to those of carnauba wax. It is an important factor that governs the thermal transferability resolution performance of the thermal transferable ink of the thermal transfer recording medium.Therefore, in order to provide the thermal transferable ink layer with the above factor, the isocyanuric acid skeleton crystalline esterified wax is used. This is the reason why the thermal transfer recording medium of the present invention, which forms the contained thermal transfer ink layer, can exhibit excellent performance such as achievement of high resolution, storage stability, and durability of the printed body after printing. In view of the above, the isocyanuric acid skeleton crystalline esterified wax is contained in the thermal transfer ink layer in a range of 5 to 95% by weight, preferably 20 to 80% by weight, more preferably 50 to 80% by weight. % Is preferably used. If the amount is less than 5% by weight, there are cases where transfer performance cannot be sufficiently exhibited as a thermal transfer ink.
If the content is more than the weight%, the concentration of the colorant becomes too low, and there is a problem in print density. In addition, in view of the gist of the present invention, the crystalline esterified wax is usually a crystalline solid wax that is solid at room temperature alone. Therefore, although it is not particularly limited, the melting point of the single substance is from room temperature to 12%.
0 ° C., preferably in the range of 40 to 100 ° C., more preferably in the range of 65 to 95 ° C. and the temperature range between the melting onset temperature and the complete melting temperature is within ± 5 ° C., preferably within ± 2 ° C. It is highly preferred to select and use crystalline esterified waxes. Further, in view of the gist of the present invention, the crystalline esterified wax usually shows a low-viscosity behavior comparable to that of carnauba wax at a relatively low melting temperature higher than the melting point alone. Therefore, the above-mentioned crystalline esterified wax group having a viscosity at 100 ° C. alone of several tens of centiponds, preferably in the range of 5 to 50 centipoise, and more preferably in the range of 5 to 35 centipoise is selected. It is highly preferred to use them.

The thermal transfer ink of the present invention can be said to be a thermoplastic thermal transfer recording ink essentially containing a fixed amount of the following colorant and the above-mentioned isocyanuric acid skeleton crystalline esterified wax. On the other hand, in the thermal transfer ink layer in the thermal transfer recording medium of the present invention, according to various purposes of a more advanced thermal transfer recording medium, it is not possible to use the following various known functional additive components in combination. It is preferable to use it without any problem. For example, a thermoplastic polymer for promoting adhesion, a tackifier, an ink cohesive force adjuster and a melt viscosity adjuster, a wax, a dispersant, a dispersing aid, a plasticizer, an oil agent, a filler, a surfactant, and a gelling agent. And a weather resistance stabilizer and the like, and may be added as a part of the thermal transfer ink component of the present invention, and are not particularly limited. The heat transferable ink layer containing the above-mentioned known thermoplastic polymer and the tackifier improves the printing adhesive property to the recording paper and exerts the effect of enabling printing with high durability. In addition, for the purpose of adjusting the melting point and the melt viscosity of the thermal transfer ink layer, by adding a known wax and or a crystalline esterified wax of the terephthalic acid skeleton or a plasticizer, from the advantage that the printing workability can be arbitrarily adjusted. It can be used preferably. Examples of the known wax include waxes such as animal waxes, vegetable waxes, mineral waxes, petroleum waxes, synthetic hydrocarbon waxes, fatty acid amide waxes, modified waxes, etc. which are solid at room temperature, and are preferably printing workability. In view of the above, the above-mentioned wax having a melting point in the range of 40 ° C. to 80 ° C. is good, and the following waxes are typical.

Animal waxes include, for example, whale wax, wool wax, insect wax, shellac wax, beeswax and the like, and vegetable waxes include, for example, carnauba wax, wood wax, onocurie wax, esbalto wax, candelilla Wax and the like. Examples of the mineral wax include montan wax, ozokerite, and ceresin. Examples of the petroleum wax include paraffin wax, microcrystalline wax, ester wax, petrolatum, and polyethylene glycol diester wax. Examples of the synthetic hydrocarbon-based wax include Fischer-Tropsch wax, polyethylene wax, low-molecular-weight polypropylene wax, low-molecular-weight polyethylene wax and derivatives thereof, and the modified wax include, for example, oxidized wax, montan wax derivative, Examples include paraffin or microcrystalline wax derivatives. Examples of the fatty acid amide wax include, for example, ethinone bisstearamide, oleic amide, stearic amide, methylene bisstearamide, methylol stearamide, and the like. In addition, one of these or 2
A combination of two or more species may be used. In the present invention, it is particularly preferable to use the terephthalic acid skeleton in combination with the crystalline esterified wax. Further, a wax which does not belong to the above-mentioned wax compound group such as hydrogenated wax, for example, caster wax and opal wax may be used in combination. Examples of the tackifier include (hydrogenated) terpene resin, (hydrogenated) terpene phenol resin, (hydrogenated) C9 petroleum resin, (hydrogenated) C5-C9 copolymerized petroleum resin, low molecular weight polystyrene resin, styrene Modified petroleum resin, aromatic tackifier resin represented by low molecular α-methylstyrene resin, etc., alicyclic tackifier resin represented by (hydrogenated) dicyclopentadiene petroleum resin, rosin ester or the like It is preferable to use one or a mixture of two or more of rosin-based tackifying resins represented by derivatives, aliphatic petroleum resins, and the like. In selecting the use of the tackifier, it is customary to select and use the resin of the present invention, if necessary, a component compatible with the hot-melt resin group, and the blending ratio in the thermal transferable ink layer is It may be used in the thermal transfer ink at most 30 parts by weight, preferably 20 parts by weight or less.

In the present invention, it is highly preferable to include the following thermoplastic polymer as one of the heat transferable ink components. That is, as the thermoplastic polymer, an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 28% by weight or less (hereinafter, simply referred to as EVA) and an ethylene-ethyl acrylate copolymer having ethyl acrylate of 35% by weight or less are used. Resin (hereinafter simply referred to as EEA), ethylene-methyl acrylate copolymer resin having methyl acrylate of 35% by weight or less (hereinafter simply referred to as EMA), crystalline polyester resin, ethylene-acrylic acid copolymer resin, ethylene-methacrylic acid Copolymer resin, styrene-ethylenebutylene-styrene block copolymer resin (hereinafter simply referred to as SE
BS), styrene-ethylene-propylene-styrene block copolymer (hereinafter simply referred to as SEPS), styrene-butadiene-styrene block copolymer (hereinafter simply referred to as SBS), and styrene-isoprene-styrene block copolymer. (Hereinafter simply referred to as SIS). One or more of thermoplastic polymers selected from these resins may be used as a thermal transfer ink component of the present invention at most 15 or more. It is a preferable example that the content is contained within the range of weight%.

Preferred plasticizers (softeners) include:
For example, castor oil, linseed oil, vegetable oils such as olive oil, animal and mineral oils such as whale oil, liquid polybutene,
Examples include synthetic oils such as liquid hydrogenated polyisoprene, paraffin oil, and naphthenic oil, polyalkylene glycols, fluorine oils, and silicone oils. As other preferable functional additive components, graphite, graphite,
Conductive derivatives such as fine metal powders, bicarbonates, carbonates, pyrolytic blowing agents such as inorganic compounds such as nitrites or organic compounds of the sulfonyl hydrazide series, thermally expandable fine particles,
Polymerization inhibitor, anti-aging agent, ultraviolet stabilizer (light-containing stabilizer), ultraviolet absorber (light-containing absorber), dispersion stabilizer, viscosity modifier (thixotropic improver), surfactant, high boiling point solvent It is also preferable to use them according to the purpose. In the present invention, means for incorporating a colorant and the crystalline esterified wax of the isocyanuric acid skeleton in the thermal transferable ink layer of the present invention, and if necessary, further functions of the thermoplastic polymer, wax and the like There is no particular limitation on the means for adding the sex-adding component, and generally, it can be obtained by dissolving and mixing or emulsifying and dispersing. In this case, when a part of the components shows immiscibility, for example, the components may be vigorously stirred and uniformly used. Further, a method of forming a finely dispersed state by removing the solvent after forming a compatible state by using a solvent can also be preferably employed. In the present invention, there is no particular limitation on the method of taking a form as a thermal transfer ink, and a crystalline esterified wax of a colorant and an isocyanuric acid skeleton, if necessary, the thermoplastic polymer, a known wax, A method in which a crystalline esterified wax of a terephthalic acid skeleton, a tackifier and the like are simultaneously melt-dispersed to form a bulk or a solution, or each component of the present invention, a method in which a colorant is separately dispersed in advance to form a solution, or the like. It is good to adopt.

The colorant used in the thermal transfer ink layer of the present invention may be appropriately selected from, for example, the following various dyes. Preferably direct dyes, acid dyes,
Examples include basic dyes, disperse dyes, oil-soluble dyes (including metal oil-soluble dyes), and the like. Further, an indoaniline dye, an azomethine dye and the like can also be preferably used. Further, the dye used in the color material layer of the present invention may be any dye that can be basically transferred (transferred) together with the heat transferable substance.
In addition to the above, organic or inorganic pigments may be used. Specific examples of the colorant used in the heat transferable ink layer of the present invention,
The following are mentioned. That is, as the yellow pigment, for example, PS Yellow GG (manufactured by Mitsui Toatsu Chemicals), PS Yellow SK (manufactured by Mitsui Toatsu Chemicals), Kayaron Polyester Light Yellow 5G-S (manufactured by Nippon Kayaku), Oil Yellow S
-7 (white clay), Aizen Spiron Yellow GRH Special (Hodogaya Chemical), Sumiplast Yellow FG
(Manufactured by Sumitomo Chemical Co., Ltd.) and Aizen Spiron Yellow GRH (manufactured by Hodogaya Chemical Co., Ltd.). As a red pigment, for example,
PS Red G (manufactured by Mitsui Toatsu Chemicals), MS Red VP (manufactured by Mitsui Toatsu Chemicals), Diaseriton Fast Red R (manufactured by Mitsubishi Chemical), Sumiplast Tread FB (manufactured by Sumitomo Chemical),
Sumiplast Red HFG (manufactured by Sumitomo Chemical), Kayaron Polyester Pink RCL-E (manufactured by Nippon Kayaku), Aizen Spiron Red GHR Specialty (manufactured by Hodogaya Chemical), and the like.

Examples of the blue pigment include Miketone Polyester Blue FBL Conc (manufactured by Mitsui Toatsu Chemicals), PE
T Blue # 2,000 (manufactured by Mitsui Toatsu Chemicals), PS Blue BN (manufactured by Mitsui Toatsu Chemicals), Diaseriton Fast Brilliant Blue (manufactured by Mitsubishi Kasei), Dianix Blue EB-E (manufactured by Mitsubishi Kasei), Kaya Ron Polyester Blue B-SF Conc (Nippon Kayaku), Sumiplast Blue 3R (Sumitomo Chemical), Sumiplast Blue G (Sumitomo Chemical) and the like. The following are typical examples of the colored application. That is, as the yellow coloring pigment, there are, for example, Hansa Yellow 3G, Tartrazine Lake and the like. Examples of the red coloring pigment include Brilliant Carmine FB-Pure (manufactured by Sanyo Dye), Brilliant Carmine 6B (manufactured by Sanyo Dye), Alizarin Lake and the like. Examples of blue color pigments include Cerulean Blue and Sumika Print Cyanine Blue GN-O.
(Manufactured by Sumitomo Chemical) and phthalocyanine blue. Typical examples of black color pigments include carbon black and oil black. The most preferred coloring agent in the present invention includes carbon black. In the present invention, the composition ratio of the thermal transfer ink is not limited, but based on 100 parts by weight of the solid content in the thermal transfer ink,
It is preferable to use the coloring material in the range of 5 to 50 parts, preferably 10 to 40 parts.

In the heat-sensitive transfer recording medium of the present invention, if necessary, a heat-transferable ink layer composed of a single layer or a composite layer such as an adhesive layer or a heat-transferable ink layer described below is formed to form a heat-sensitive transfer recording medium. Good to do. The following composition can be preferably used for the adhesive layer of the present invention. That is, EV
A, EEA, EMA, saturated polyester resin, ethylene-acrylic acid copolymer resin, ethylene-methacrylic acid copolymer resin, SEBS, SEPS, SBS, SIS, ionomer resin, polyethylene resin, polypropylene resin, polyamide resin, vinyl chloride resin ,acrylic resin,
A thermoplastic urethane resin, butyl rubber, polyisobutylene rubber, or the like is included as a main component, and the above-mentioned known wax component, an adhesive layer composition with the same tackifier, and the like can be preferably used. As the intermediate thermal transfer ink layer, the thermal transfer ink layer of the present invention may be used as it is, or a known thermal transfer ink layer may be used, and the thermal transfer ink component composition is not particularly limited. Absent.
Also, there may be no problem if the composition of the adhesive layer is an intermediate layer containing the above-mentioned coloring agent. That is, in the present invention, as a thermal transfer recording medium exhibiting printability many times,
For example, when the thermal transfer recording material is a thermal transfer recording material composed of a composite layer, the colorant and the crystalline ester which are solid at room temperature of the present invention may be added to any one or several layers, preferably to all the composite layers. Any type of thermal transfer recording medium in which a thermal transferable ink layer made of activated wax is laminated can be adopted. In the present invention, the preferred form of the thermal transfer recording medium in the case where the support itself is a support of a microporous film is not particularly limited. For example, the solid colorant and the isocyanurate at room temperature of the present invention may be used. In general, the layer is sufficiently impregnated with a thermal transfer ink composed of a crystalline esterified wax having an acid skeleton.

In the heat-sensitive transfer recording medium of the present invention, a technique suitable for appropriately applying the composition for the adhesive layer and the composition for the heat transferable ink layer onto the support film is to use a known technique. good. For example, hot melt coating, or solvent coating using a coating solution obtained by dissolving the composition in a solvent, or a method of once dispersing in an aqueous medium and then applying an emulsion, etc. It may be appropriately selected and adopted. It is highly preferable to form the thermal transfer recording medium of the present invention using a material which is an aqueous dispersion, including the thermal transfer ink layer of the present invention and, if necessary, an adhesive layer, in particular from the following points. In general, if the thermal transfer ink layer has an excessively high cohesive force than necessary, it is expected that the heat transfer ink composition at the boundary between the heated portion and the non-heated portion will be poorly cut when heat is applied. This is because a method of forming an aqueous dispersion using the coating composition is recommended as a technique that can easily avoid the above factors.

That is, the method of forming with the coating composition in the form of an aqueous dispersion is as follows: (a) Even if a thermal transfer ink having a high cohesive force and a high melt viscosity is used, a functional layer which easily exhibits excellent printability can be formed. Things that are possible. (I) The ability to mix and disperse various types of materials in any proportion if attention is paid to the ionicity of the aqueous dispersion. (U) Thin film coating is easy. (E) Lamination coating is easy. (Iii) The transferred image is sharply cut when heat is applied, and high-density, relatively low-energy heating printing can be performed. This is because such advantages can be cited as advantages. The thermal transfer ink layer of the present invention, as a method of forming and applying each layer such as an adhesive layer as needed, a reverse roll coater method, an extrusion coater method, a gravure coater method, a wire bar coating method, and the like,
Known techniques can be employed. Further, the thickness of the formed coating film of the heat transferable ink layer of the present invention is not limited, but in the case of lamination on a smooth film, it is generally 20 μm or less, preferably 15 μm or less, more preferably 3 to 10 μm. good. In the case of using a microporous film support, it is preferable to adjust the thickness of the film to a thickness slightly exceeding the thickness of the film or a few microns. In the present invention, the preferable thickness of the adhesive layer when the adhesive layer is applied as necessary is not limited, but is generally 5 μm or less, preferably 0.1 to 2 μm. Micron range is good.

[0021]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not particularly limited. In the examples, "%" and "part" mean "% by weight" and "part by weight", respectively. Comparative Example 1 The following heat transfer ink layer was coated on a 3.5 μm thick polyethylene terephthalate film support provided with an adhesive layer of a 1 μm thick ethylene-vinyl acetate resin (vinyl acetate content: 80%). The aqueous dispersion mixture composition was applied by a flow coater coating method so as to have a dry film thickness of 10 μm to obtain a thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) [A-1]. Ethylene-vinyl acetate copolymer resin: 10 parts Carnauba wax (melting point: 81-86 ° C): 65 parts Microcrystalline wax (softening point: 80 ° C) Hi-Mic-1070 manufactured by Nippon Seiwa Co., Ltd .: 10 parts Carbon black (carbon black / dispersion) (Material = 20/5) (Mitsubishi Kasei Kogyo Co., Ltd. MA100): 15 parts This thermal transfer recording medium sample [A-1] is commercially available using a thermal printer (a device incorporating a thermal head with a heating element density of 16 Dot / mm). Table 1 shows the results of a recording and printing test performed on plain paper.

COMPARATIVE EXAMPLE 2 A film of a heat-sensitive transfer recording medium was prepared by impregnating a support of a microporous nonwoven fabric having a thickness of 20 μm with a hot-melt type heat-transferable ink composition for a heat-transferable ink layer described below. And a thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) [A-2] was obtained. Ethylene-vinyl acetate copolymer resin: 10 parts Carnauba wax (melting point: 81-86 ° C): 65 parts Microcrystalline wax (softening point: 80 ° C) Hi-Mic-1070 manufactured by Nippon Seiwa Co., Ltd .: 10 parts Carbon black (carbon black / dispersion) Agent = 20/5) (Mitsubishi Kasei Kogyo Co., Ltd. MA100): 15 parts This thermal transfer recording medium sample [A-2] is commercially available using a thermal printer (a device having a built-in thermal head with a heating element density of 16 Dot / mm). Table 1 shows the results of a recording and printing test performed on plain paper.

Example 1 On a support having the same adhesive layer as obtained in Comparative Example 1,
Flow coater coating an aqueous dispersion mixture composition for a thermal transferable ink layer having the following composition,
Thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) B coated by applying so that the thickness of the thermal transferable ink layer becomes 10 μm.
I got Ethylene-ethyl acrylate copolymer resin: 1
0 parts Tris (2-hydroxyethyl) isocyanurate 2
Synthetic esterified wax having a Shore D hardness of 56 to 57 (0 second value) at room temperature, which is a behenic acid adduct (purity: 95 to 97%) (melting point: 82 to 83 ° C): 65 parts Paraffin wax (softening point) 65 ° C.): 10 parts carbon black (carbon black / dispersant = 20 /
5) (Mitsubishi Kasei Kogyo Co., Ltd. MA100): 15 parts This thermal transfer recording medium sample B was subjected to a recording / printing test on commercially available plain paper using a thermal printer (a device having a built-in thermal head with a heating element density of 16 Dot / mm). The results are shown in Table 1.

Example 2 In place of the carnauba wax shown in Comparative Example 1, the following two types of crystalline esterified waxes were used in a weight ratio of (a) 2:
(B) A thermal transfer recording medium sample (8-mm-wide ribbon-shaped specimen) C was obtained in the same manner as in (1). (A) As a crystalline esterified wax, a 3-stearic acid adduct of tris (2-hydroxyethyl) isocyanurate (purity: 97 to 99%) having a Shore D hardness of 43 to 44 (0 second value) at room temperature. Synthetic esterified wax (melting point: 76-79 ° C.) (b) 2-behenic acid adduct of bis (2-hydroxyethyl) terephthalate (purity: 97-99%) as crystalline esterified wax Synthetic wax Sample C of this thermal transfer recording medium Was recorded and printed on commercially available plain paper using a thermal printer (a device having a built-in thermal head with a heating element density of 16 Dot / mm). The results are shown in Table 1.

Example 3 A thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) D was prepared in the same manner except that the following crystalline esterified wax was used in place of the carnauba wax shown in Comparative Example 2. Obtained. Synthetic esterification which is 3-behenic acid adduct of tris (2-hydroxypropyl) isocyanurate (purity 92-95%) as a crystalline esterified wax and has a Shore D hardness of 50-53 (0 second value) at room temperature. Wax This thermal transfer recording medium sample D was subjected to a recording and printing test on commercially available plain paper using a thermal printer (a device having a built-in thermal head with a heating element density of 16 Dot / mm). The results are shown in Table 1.

Example 4 A 3.5 μm thick polyethylene terephthalate film support provided with a 1 μm thick ethylene-vinyl acetate resin (vinyl acetate content of 80%) adhesive layer was used for the following thermal transfer ink layers. The applied aqueous dispersion mixture compositions (1) and (2) were applied to a flow coater coating method, and the dry film thickness was 10 μm of (1) +5 of (2).
μm = 15 μm in total to obtain a thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) E. (1) Aqueous dispersion mixture composition for thermal transfer ink layer Ethylene-ethyl acrylate copolymer resin having MI value of 150 gr on average: 10 parts 3-behenine of tris (2-hydroxyethyl) isocyanurate as a crystalline esterified wax Acid adduct: 6
5 parts Natural montan wax: 10 parts Carbon black: 15 parts (2) Coating aqueous dispersion mixture composition for thermal transfer ink layer Ethylene-ethyl acrylate copolymer resin having MI value of 275 gr: 10 parts As crystalline esterified wax 3-palmitic acid adduct of tris (2-hydroxyethyl) isocyanurate:
65 parts Natural montan wax: 10 parts Carbon black: 15 parts Recording and printing test of this thermal transfer recording medium sample E on a commercially available plain paper using a thermal printer (a device incorporating a thermal head with a heating element density of 16 Dot / mm) Are shown in Table 1.

[0027]

[Table 1]

[0028]

As is clear from the results in Table 1 above,
It was found that the samples B to E of the present invention exhibited print operability and print recordability that were not inferior to (almost equivalent to) those of the conventional thermal transfer recording media samples A-1 and A-2. In all of the examples, printing of a transferred image with no cut or lack of transfer was performed on plain paper having a Beck smoothness of 5 to 20. And 35 ° C
-No blocking phenomenon was observed in the test specimen which was wound and stored in an atmosphere of 65% RH for a long time. This is the main object of the present invention, which is to obtain a superior thermal transfer recording medium comparable to the conventional one without using carnauba wax at all, as compared with the conventional high-performance thermal transfer recording medium mainly comprising carnauba wax. It turns out that it is possible. That is, the thermal transfer recording medium of the present invention contains a colorant as a thermal transferable ink layer which is solid at room temperature and a crystalline esterified wax having an isocyanuric acid skeleton represented by the above general formula (1) as a solid component. The thermal transfer recording medium on which the thermal transfer ink layer is formed shows sufficient high printing workability and good storage stability, and further has important physical properties such as high-resolution printing property and multiple-time printing property as required. The most important feature is that an excellent thermal transfer recording medium can be obtained without using carnauba wax.

Claims (6)

(57) [Claims] 1. A heat-sensitive transfer recording medium, comprising a heat transferable ink layer formed on a support, wherein the heat transferable ink layer contains a colorant and a solid component at normal temperature. The solid component has the following general formula (1) [Wherein, A represents an isocyanuric group (residue of hydrogen substituted with isocyanuric acid), X represents an alkylene group or an alkenyl group represented by an integer having 2 to 5 carbon atoms;
Represents -X-OOCR ₃ or -X-OH group. R ₁ , R ₂ and R ₃ each represent a higher alkyl group or an alkenyl group represented by an integer having 12 to 30 carbon atoms. A crystalline wax selected from the group of isocyanuric acid esters represented by the formula
A heat-sensitive transfer recording medium characterized in that it is contained in a range of weight%. 2. In a thermal transfer recording medium comprising a support and one or more thermal transfer ink layers formed thereon via an adhesive layer, any or all of the thermal transfer ink layers. Contains a colorant and a solid component having a Shore D hardness of 45 or more at room temperature, wherein the solid component is a solid component.
A thermal transfer method characterized in that one to one or a mixture of two or more crystalline waxes selected from the group of isocyanuric acid esters represented by the general formula (1) are contained in the range of 5 to 95% by weight. recoding media. 3. A thermal transfer recording medium comprising a heat transferable ink layer formed on a support exhibiting microporous properties, wherein the heat transferable ink layer has a colorant and a Shore D hardness of 45 at room temperature. A crystalline wax selected from the group of the isocyanuric acid esters represented by the general formula (1) according to claim 1, which comprises a solid component as described above.
A heat-sensitive transfer recording medium characterized in that the medium contains at least one species or a mixture of two or more species. 4. The crystalline wax has a melting point of 65 to 95 ° C.
The thermal transfer recording medium according to claim 1, wherein 5. A crystalline wax comprising tris (2-hydroxyethyl) isocyanurate adduct of 2 or 3 stearic acid, tris (2-hydroxyethyl) isocyanurate adduct of 2 or 3 palmitic acid, and tris (2-hydroxyethyl) isocyanurate.
2 or 3 myristic acid adduct of hydroxyethyl) isocyanurate, 2 or 3 behenic acid adduct of tris (2-hydroxyethyl) isocyanurate, 2 or 3 stearic acid adduct of tris (2-hydroxypropyl) isocyanurate, 2 or 3 palmitic acid adduct of tris (2-hydroxypropyl) isocyanurate, 2 or 3 myristic acid adduct of tris (2-hydroxypropyl) isocyanurate, 2 or 3 behenin of tris (2-hydroxypropyl) isocyanurate 5. The thermal transfer recording medium according to claim 1, wherein the thermal transfer recording medium is an acid adduct. 6. A solid component comprising the crystalline wax of claim 1 and the following component (B) in an amount of at most 30% by weight.
6. The heat-sensitive transfer recording material according to claim 1, wherein at least 15% by weight of the component (C) is used in combination. (B) Animal wax, plant wax, mineral wax, petroleum wax, synthetic paraffin wax, fatty acid amide wax, modified wax oxidized or acid-modified, the following general formula (2): R ₄ COO- (ZO) ) N-OC-R-CO- (O-Z) n-Q (2) [wherein, R represents a phenylene group, and Z has 2 carbon atoms.
Represents an alkylene group of 5 to 5, and Q is -OOCR ₅ or-
Represents an OH group. R ₄ and R ₅ each have a carbon number of 12 to
30 represents a higher alkyl group or an alkenyl group, and n represents an integer of 1 to 50. One or more selected from the group of crystalline waxes of terephthalic acid esters represented by the formula:
(C) an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 28% by weight or less, an ethylene-ethyl acrylate copolymer resin having ethyl acrylate of 35% by weight or less,
Ethylene-methyl acrylate copolymer resin containing 35% by weight or less of methyl acrylate, crystalline saturated polyester resin, ethylene-acrylic acid copolymer resin, ethylene-methacrylic acid copolymer resin, styrene-ethylene-butylene-styrene block copolymer resin , Styrene-ethylene-
Propylene-styrene block copolymer resin, styrene-
Butadiene-styrene block copolymer resin, styrene-
One or a mixture of two or more heat-fusible resin materials selected from styrene block copolymer resins such as isoprene-styrene block copolymer resins.