JP2947973B2 - 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 As a heat-sensitive transfer recording medium disclosed as a prior art, for example, JP-A-55-105579,
JP-A-63-268693 discloses a technique of forming a fine porous layer and impregnating the layer with a heat transferable ink. JP-A-57-160691 discloses a technique of forming a network structure using organic or inorganic fine powder and impregnating with a thermal transfer ink. JP-A-57-185192 discloses a technique for impregnating porous paper with a thermal transfer ink. The above-mentioned known technique discloses a technique relating to a structure of a support 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. For example, 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 increasingly important. There is an entity in which the center of the binder component for use is mainly carnauba wax. Carnauba wax has a melting point of 81 to 86 ° C., exhibits excellent thermal transfer printability and storage stability, and has excellent print durability after printing. It can be said to be the main material of the binder component. In addition, carnauba wax itself has properties such as hard, good gloss, etc., so with the use of glazing wax for furniture, automotive wax, hot melt adhesive, etc., A major problem is its availability. That is, carnauba wax is a natural wax, and its supply in the market is limited, and there is a current situation in which it cannot be sufficiently used for binders for thermal transfer recording media which are increasing more and more. Therefore, in the heat-sensitive transfer recording medium market, the emergence of an alternative wax instead of carnauba wax is eagerly desired. In view of the above prior art, it is a main object of the present invention to use a carnauba wax as a binder component for a thermal transfer ink at all or to use a very small amount thereof to obtain an excellent thermal transfer recording medium. That is, a novel thermal transfer ink component capable of exhibiting substantially the same properties as conventionally known thermal transfer inks mainly containing carnauba wax, and excellent thermal transferability using the novel thermal transfer ink component ( It is an object of the present invention to provide a heat-sensitive transfer recording medium having high density and high resolution) and excellent storage stability, and a heat-sensitive transfer recording medium capable of printing many times as required.

[0004]

The thermal transfer recording material of the present invention comprises a heat transferable ink layer formed on a support, and the heat transferable ink layer contains a colorant and a solid component at normal temperature. In the thermal transfer recording medium, the solid component is represented by the following general formula (1) or (2): R ₁ COO- (X-O) _n -OC-Y-CO- (OX) _n —OOCR ₂ (1) R ₁ COO— (X—O) _n —OC—Y—CO— (OX) _n —OH (2) [wherein, X is an integer of 2 to 5 carbon atoms. Y represents a phenylene group, R ₁ and R ₂ each represent a higher alkyl group or an alkenyl group represented by an integer having 12 to 30 carbon atoms, and n represents a number of 1 to 50. ]
The present invention relates to a heat-sensitive transfer recording medium characterized in that one or more selected from the group of crystalline esterified waxes having a terephthalic acid skeleton represented by the formula (1) are contained in the range of 5 to 95% by weight. 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 as viewed from the support surface may be used. The layer contains a colorant and a solid component having a Shore D hardness of 45 or more at room temperature, and the solid component is a crystalline esterification of a terephthalic acid skeleton represented by the general formula (1) or (2). 5 to 95% by weight of one or a mixture of two or more kinds selected from the group of waxes
It is also possible to use a heat-sensitive transfer recording medium which can be printed a number of times, characterized by being contained in the range described above. Further, in a thermal transfer recording medium comprising a heat transferable ink layer formed on a support having a microporous property, the heat transferable ink layer is a colorant and a solid having a Shore A hardness of 45 or more at room temperature. And a mixture of at least one selected from a group of crystalline esterified waxes having a terephthalic acid skeleton represented by the above general formula (1) or (2). A thermal transfer recording medium which can be printed a number of times, characterized in that it is contained in the range of up to 95% by weight, is also highly preferred. Further, as the crystalline esterified wax having a terephthalic acid skeleton represented by the general formula (1) or (2), one or more selected from the group of crystalline esterified waxes having a melting point in the range of 65 to 95 ° C. The thermal transfer recording medium characterized in that it comprises a mixture of two or more types is highly preferred.

Further, as a crystalline esterified wax having a terephthalic acid skeleton represented by the general formula (1) or (2), bis (2-hydroxyethyl) terephthalate adduct of 1 or 2 stearic acid and bis (2- 1- or 2-palmitic acid adduct of hydroxyethyl) terephthalate, 1-bis (2-hydroxyethyl) terephthalate
Or 2 myristic acid adduct, 1 or 2 behenic acid adduct of bis (2-hydroxyethyl) terephthalate, 1 or 2 of bis (2-hydroxypropyl) terephthalate
Stearic acid adduct, bis (2-hydroxypropyl)
1 or 2 palmitic acid adduct of terephthalate, 1 or 2 of bis (2-hydroxypropyl) terephthalate
Myristic acid adduct, bis (2-hydroxypropyl)
The thermal transfer recording medium, characterized in that it contains one or a mixture of two or more terephthalate adducts of one or two behenic acids, is particularly preferred. Further, as a solid component in the thermal transfer ink layer, animal wax, plant wax, mineral wax, petroleum wax, synthetic paraffin wax, fatty acid amide wax, polyester oligoester wax, oxidized or acid-modified wax. The heat-sensitive transfer recording material is characterized in that at least 30% by weight of at least 30% by weight is used in combination with one or more mixtures selected from the group of heat-fusible substances of modified wax. .

Further, as a solid component in the thermal transfer ink layer, an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 28% by weight or less, and an ethylene-ethyl acrylate copolymer having an ethyl acrylate of 35% by weight or less. Polymerized resin, 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 Hot melting selected from the group of styrene block copolymer resins such as copolymer resins, styrene-ethylene-propylene-styrene block copolymer resins, styrene-butadiene-styrene block copolymer resins, and styrene-isoprene-styrene block copolymer resins. One of the conductive resin substances or A mixture of more species, the thermal transfer recording medium characterized by comprising in combination use within 15 wt% at most even the most highly preferred. Hereinafter, the present invention will be described in more detail.

As described above, the heat-sensitive transfer recording medium of the present invention comprises the following heat-transferable ink layer formed on the following support, and the heat-transferable ink layer is preferably formed by a colorant and a normal temperature. Is a heat-sensitive transfer recording medium containing a solid component having a Shore A hardness of 45 or more. As the support used in the thermal transfer recording medium of the present invention, as one kind thereof, thermal rigidity (heat resistance)
It is preferable to use a material rich in dimensional stability and surface smoothness. As another type, there is no problem even if it is a microporous support such as paper or fiber. Generally, the support generally has the following properties. One of them is that 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. Second, it is desirable 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). . Examples of such paper include papers 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-resin films. A composite, a metal film such as aluminum foil, a metal foil-resin film composite such as aluminum, a metal composite such as paper-aluminum, a paper-metal foil-resin film composite, and the like can be suitably used. The surface of the support that is in direct contact with the thermal head is provided with a heat-resistant protective layer of silicone resin, soft resin, polyimide resin, polycarbonate resin, phenol resin, melamine resin, nitrocellulose, etc. A support material having improved properties may be employed. The thickness of the support is not particularly limited, but is generally 60 μm or less, preferably 30 μm or less, and particularly preferably 2 μm to 20 μm, for obtaining good thermal conductivity. 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 side of the support, and may be arbitrary, such as an anti-blocking layer and an anti-sticking layer.
A support having a general backing layer may be used.

The heat-sensitive transfer recording material of the present invention is preferably an embodiment of a heat-sensitive transfer recording material using the following heat transferable ink component comprising one or more heat transferable ink layers on a support with an adhesive layer interposed therebetween. The reason is that it is recommended as an excellent thermal transfer recording medium that can be printed many times, and there is no particular limitation. Preferably, when two or more thermal transferable ink layers are formed, the uppermost layer is thermally transferred. It is preferable to form the layer so as to increase the property (so that the melting temperature is lower than that of the lower layer or the melt viscosity is lower than that of the lower layer). Further, the thermal transfer recording medium of the present invention is also preferably a mode of a thermal transfer recording medium using the following thermal transferable ink component formed by forming a thermal transferable ink layer on a support having microporous properties. The reason for this is that it is also recommended as an excellent thermal transfer recording medium that can be printed many times. As a support exhibiting such microporous properties, a known support may be used, and in particular, there is no particular limitation. However, it is preferable to use a microporous support selected from paper, nonwoven fabric, or a multiplicity of the above-mentioned supports according to the purpose. In the thermal transfer recording medium described above, each layer of the adhesive layer and each of the thermal transfer ink layers composed of one or more layers may be layers each having a desired function. In the thermal transfer recording medium, the terephthalic acid skeleton represented by the general formula (1) or (2) is provided on at least one of the transfer layers or on all of the thermal transfer ink layers. It is important for achieving the object of the present invention to contain one or more kinds of mixtures selected from the group consisting of crystalline esterified waxes in the range of 5 to 95% by weight.
That is, the crystalline esterified wax having a terephthalic acid skeleton represented by the general formula (1) or (2) is typically obtained by the following method.

For example, bis (2-hydroxyethyl) terephthalate, a 2-ethylene oxide adduct of terephthalic acid, bis (2-hydroxypropyl) terephthalate, a 2-propylene oxide adduct of terephthalic acid, and 2-butylene oxide addition of terephthalic acid Fatty acids and / or acid anhydrides and / or lower alkyl esterified fatty acid derivatives thereof with respect to the active hydroxyl group of bis (2-hydroxyalkyl) terephthalate represented by bis (2-hydroxybutyl) terephthalate and the like A typical example is a product obtained by subjecting a compound to an esterification reaction or a transesterification reaction (a dealcoholization ester reaction). Furthermore, bis (polyethylene glycol) terephthalate which is a 4-100 ethylene oxide adduct of terephthalic acid, bis (polypropylene glycol) terephthalate which is a 4-10 propylene oxide adduct of terephthalic acid, and 4-10 butylene oxide addition of terephthalic acid The following fatty acids and / or their acid anhydrides and / or their lower alkyl esterified fatty acid derivatives are esterified to the active hydroxyl groups of bis (polyalkylene glycol) terephthalate represented by bis (polybutylene glycol) terephthalate, etc. A product obtained by a conversion reaction or a transesterification reaction (a dealcoholization ester reaction) is also a preferred example. Preferably, bis (2-hydroxyethyl) terephthalate and / or bis (2-
The use of (hydroxypropyl) terephthalate as a starting material is the most preferable method for synthesizing the crystalline esterified wax having a terephthalic acid skeleton according to the present invention.

In the present invention, fatty acids and / or acid anhydrides and / or lower alkyl esterified fatty acid derivatives thereof are collectively referred to as fatty acids in the following description. The generic term fatty acid is a saturated fatty acid or unsaturated fatty acid having an integer of 12 to 30 carbon atoms, and specific examples thereof include the following. For example, lauric acid, myristic acid, palmitic acid, stearic acid, tridecanoic acid, nonadecanoic acid, behenic acid, oleic acid, heptadecanoic acid,
Representative examples thereof include fatty acids such as norbornic acid, tetracosanoic acid, tricosanoic acid, hexacosanoic acid, hepetacosanoic acid, and octacosanoic acid, and their acid anhydrides and lower alkyl esterified fatty acid derivatives thereof. Specifically, the expression of lower alkyl is a general term and means an alkyl group represented by an integer having 5 or less carbon atoms, a halogenated alkyl group, a phenyl group, a naphthyl group, and the like. In the present invention, the crystalline esterified wax having a terephthalic acid skeleton includes one or two stearic acid adducts of bis (2-hydroxyethyl) terephthalate and one or two palmitic acid adducts of bis (2-hydroxyethyl) terephthalate. Of bis (2-hydroxyethyl) terephthalate
Or 2 myristic acid adduct, 1 or 2 behenic acid adduct of bis (2-hydroxyethyl) terephthalate,
Bis (2-hydroxypropyl) terephthalate 1 or 2 stearic acid adduct, bis (2-hydroxypropyl) terephthalate 1 or 2 palmitic acid adduct, bis (2-hydroxypropyl) terephthalate 1 or 2 myristic acid adduct It is preferable to use one or more of adduct of bis (2-hydroxypropyl) terephthalate and 1 or 2 behenic acid. The reason is that wax hardness is relatively high at room temperature. In addition, the properties as a thermal transferable ink can achieve a Shore A 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 of a thermal transfer ink should be able to achieve a Shore A hardness of 45 or more, and exhibit extremely sharp melting point behavior. Furthermore, the melt viscosity and melting point of the wax alone should be close to those of carnauba wax. Is considered to be an important factor that governs the thermal transferability resolution performance of the thermal transferable ink of the thermal transfer recording medium. Therefore, in the heat-sensitive transfer recording medium using the crystalline esterified wax having a terephthalic acid skeleton according to the present invention as a binder component in which these factors were determined for the heat transferable ink, achievement of high resolution, storage stability, and a printed body after printing were achieved. This is the reason why excellent performance such as durability can be exhibited.

The crystalline esterified wax having a terephthalic acid skeleton according to the present invention is incorporated in the following thermal transfer ink layer in the range of 5 to 95% by weight, preferably 20 to 80% by weight, based on the gist thereof. More preferably, it is used in the range of 50 to 80% by weight. If the amount is less than 5% by weight, the transfer performance may not be sufficiently exhibited as a thermal transferable ink in some cases. If the amount is more than 95% by weight, the concentration of the colorant becomes too low, and there is a problem in print density. According to the gist of the present invention, the crystalline esterified wax having a terephthalic acid skeleton according to the present invention is usually a single crystalline solid at normal temperature. Therefore, although not particularly limited, the melting point of the compound alone is in the range of room temperature to less than 120 ° C, preferably in the range of 40 to 100 ° C, more preferably in the range of 65 to 95 ° C. It is highly preferred to select and use the terephthalic acid skeleton crystalline esterified wax having a temperature range of ± 5 ° C., preferably ± 2 ° C.

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 crystalline esterified wax having a terephthalic acid skeleton. 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. No problem. For example, a thermoplastic polymer or tackifier for promoting adhesion, a cohesive force adjustment and melt viscosity modifier for the ink, a wax, a dispersant,
Dispersing aids, plasticizers, oils, fillers, surfactants, gelling agents, weathering stabilizers and the like, and may be added as a part of the thermal transfer ink component of the present invention, and in particular Not restricted. 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. Further, for the purpose of adjusting the melting point and the melt viscosity of the thermal transfer ink layer, a known wax and / or a plasticizer may be added, so that the printing workability can be arbitrarily adjusted.

Known waxes usable in the present invention include animal waxes, plant waxes, mineral waxes, petroleum waxes, fatty acid amide waxes, polyester oligoester waxes, and synthetic hydrocarbon waxes which are solid at room temperature. Waxes such as waxes and modified waxes, preferably the above-mentioned waxes having a melting point in the range of 40 ° C. to 150 ° C. from the viewpoint of printing workability, are specifically exemplified by the following waxes. As animal-based wax, for example,
Whale wax, wool wax, insect wax, shellac wax, beeswax, and the like. Examples of plant waxes include carnauba wax, wood wax, onocurie wax, esbalto wax,
Candelilla wax and the like. Examples of the mineral wax include montan wax, ozokerite, and ceresin, and examples of the petroleum wax include paraffin wax, microcrystalline wax, ester wax, petrolatum, and polyethylene glycol diester wax. Examples of the synthetic hydrocarbon wax include Fischer-Tropsch wax, polyethylene wax, low-molecular-weight polypropylene wax, low-molecular-weight polyethylene wax, and derivatives thereof.

Examples of the fatty acid amide wax include, for example, stearic acid amide, parimitic acid amide, methylene bis stearoamide, methylol stearoamide and the like. As the polyester oligoester wax, for example, the average molecular weight of aliphatic diol and aromatic dicarboxylic acid represented by an integer having 2 to 6 carbon atoms is 500.
And a synthetic saturated polyester wax having a number-average molecular weight to a weight-average molecular weight ratio of 2 or more. As the modified wax, for example, oxidized wax,
Examples include montan wax derivatives, paraffin or microcrystalline wax derivatives. One or more of these known waxes may be used in combination. In the present invention, a hydrogenated wax, for example, a wax that does not belong to the above-mentioned wax compound group such as caster wax and opal wax can be used in combination. Examples of the tackifier usable in the present invention include (hydrogenated) terpene resin, (hydrogenated) terpene phenol resin, (hydrogenated) C9 petroleum resin, (hydrogenated) C5-C9 copolymerized petroleum resin, and low molecular weight Polystyrene resin, styrene-modified petroleum resin,
Aromatic tackifier resins represented by low-molecular α-methylstyrene resins, etc .; alicyclic tackifier resins represented by (hydrogenated) dicyclopentadiene petroleum resins; rosin esters or derivatives thereof. Rosin-based tackifying resin,
It is preferable to use one kind or a mixture of two or more kinds of aliphatic petroleum resins. In selecting the use of the tackifier,
It is customary to select and use the resin of the present invention and, if necessary, a component having compatibility with the hot-melt resin group. The compounding amount in the thermal transfer ink layer may be at most 30 parts by weight, preferably at most 20 parts by weight, per 100 parts of the thermal transfer ink agent.

In the present invention, the following thermoplastic polymers are generally used for the purpose of improving print adhesion, cohesive strength and toughness of a thermal transfer ink. Examples of the thermoplastic polymer include 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 resin having an ethyl acrylate content of 35% by weight or less. (Hereinafter simply referred to as EEA), an ethylene-methyl acrylate copolymer resin having methyl acrylate of 35% by weight or less (hereinafter simply referred to as EMA), a crystalline polyester resin, an ethylene-acrylic acid copolymer resin, and an ethylene-methacrylic acid copolymer resin. Polymerized resin, styrene-ethylene-butylene-styrene block copolymer (hereinafter simply referred to as SEBS), styrene-ethylene-propylene-styrene block copolymer (hereinafter simply referred to as SEPS), and styrene-butadiene-styrene block copolymer (Hereinafter simply called SBS) or styrene Styrene block copolymer resins such as isoprene-styrene block copolymer resin (hereinafter simply referred to as SIS) and the like, and one or a mixture of two or more selected from these thermoplastic polymers may be used in the thermal transfer of the present invention. It is preferable to include it as one of the ink components. Plasticizer (softener)
As, for example, castor oil, linseed oil, vegetable oils such as olive oil, animal oils and mineral oils such as whale oil, liquid polybutene, liquid hydrogenated polyisoprene, paraffin oil, synthetic oils such as naphthenic oil, polyalkylene glycol, and fluorine oil And silicone oil. Other functional additive components include 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 possible to use such as according to the purpose.

In the present invention, a means for incorporating a colorant and the crystalline esterified wax having a terephthalic acid skeleton into the thermal transferable ink layer of the present invention, and if necessary, further comprising the thermoplastic polymer; Means for incorporating a functional additive component such as a wax and a tackifier is not particularly limited, and may generally 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, the handling form as the heat transferable ink is not particularly limited, and a colorant and a crystalline esterified wax having a terephthalic acid skeleton, if necessary, the above thermoplastic polymer, a known wax, a tackifier, and the like May be employed as a solution or a solution in which the components are simultaneously melt-dispersed into a bulk or a solution, or the respective components of the present invention and the colorant are separately dispersed in advance to form a solution. The colorant used in the heat transferable ink layer of the present invention may be, for example, appropriately selected from the following various dyes and used. Preferable examples include direct dyes, acid dyes, 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 used. The dye used in the color material layer of the present invention may be any dye that can basically be transferred (transferred) together with the heat transferable substance, and may be an organic or inorganic pigment in addition to the above.

Specific examples of the colorant used in the heat transferable ink layer of the present invention include the following. As the yellow pigment, for example, PS Yellow GG (Mitsui Toatsu Chemicals), PS Yellow SK (Mitsui Toatsu Chemicals), Kayaron Polyester Light Yellow 5GS (Nippon Kayaku), Oil Yellow S-7 (Shirachi) , Aizen Spiron Yellow GRH Special (Hodogaya Chemical), Sumiplast Yellow FG (Sumitomo), Aizen Spiron Yellow GRH
(Hodogaya Chemical). 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 (Mitsubishi Kasei), Sumiplast Tread FB (Sumitomo), Sumiplast Tread HFG ( Sumitomo Chemical), Kayaron Polyester Pink RCL-E (Nippon Kayaku), Aizen Spiron Red GHR Specialty (Hodogaya Chemical), and the like. Examples of the blue pigment include Miketone Polyester Blue FBL Conc (Mitsui Toatsu Chemicals), PE
T Blue # 2,000 (Mitsui Toatsu Chemicals), PS Blue B
N (Mitsui Toatsu Chemicals), Diaseriton Fast Brilliant Blue (Mitsubishi Kasei), Dianix Blue EB-
E (Mitsubishi Kasei), Kayaron polyester blue B-SF
Conch (Nippon Kayaku), Sumiplast Blue 3R (Sumitomo Chemical), Sumiplast Blue G (Sumitomo Chemical) and the like.

The following are typical examples of colored application materials. Examples of yellow color pigments include Hansa Yellow 3G and Tartrazine Lake.
Examples of red coloring pigments include Brilliant Carmine FB-Pure (Sanyo Dye), Brilliant Carmine 6
B (Sanyo Dye), Alizarin Lake and the like. Examples of blue color pigments include Cerulean Blue, Sumika Print Cyanine Blue GN-O (Sumitomo), and Phthalocyanine Blue. Typical examples of the black coloring pigment 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 the solid content in the thermal transfer ink is 1%.
It is preferable to use the colorant in an amount of 5 to 50 parts, preferably 10 to 40 parts with respect to 00 parts by weight. In the heat-sensitive transfer recording medium of the present invention, a heat-transferable recording medium may be formed by forming a heat-transferable ink layer comprising an adhesive layer or a single layer or a composite layer as necessary. In the present invention, the following adhesive composition can be used for the adhesive layer as needed.

As such an adhesive composition, for example,
EVA, EEA, EMA, saturated polyester resin, ethylene-acrylic acid copolymer resin, ethylene-methacrylic acid copolymer resin, SEBS, SEPS, SBS, SIS,
Contains ionomer resin, polyethylene resin, polypropylene resin, polyamide resin, vinyl chloride resin, acrylic resin, thermoplastic urethane resin, butyl rubber, polyisobutylene rubber, etc. as main components, and contains the above-mentioned known wax components, the same tackifier, etc. Compositions 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.
The composition of the adhesive layer may be an intermediate layer containing the above-mentioned coloring agent. In the present invention, as a thermal transfer recording medium exhibiting printability many times, for example, when the thermal transfer ink layer is a thermal transfer recording material composed of a composite layer, in any one or several layers, preferably Any of the heat-sensitive transfer recording media in which the heat transferable ink layer comprising the colorant solid at room temperature and the crystalline esterified wax of the present invention is laminated on all the composite layers can be adopted. In the present invention, when the support itself is a support of a microporous film, the preferred form of the thermal transfer recording medium is not particularly limited, but, for example, a solid colorant at room temperature and a crystalline terephthalic acid skeleton. In general, the layer is sufficiently impregnated with a thermal transfer ink composed of an esterified wax.

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 a support film may be selected from known techniques. Is good. For example, hot melt coating, or using a coating solution obtained by dissolving the composition with a solvent, solvent coating, or a method of once dispersing in an aqueous medium and then applying an emulsion, and the like. The method may be appropriately selected and adopted. It is highly preferable to form the heat-sensitive transfer recording medium of the present invention by using a water-dispersible material, including the thermal transfer ink layer of the present invention and, if necessary, an adhesive layer, in particular from the following points. In general, when the thermal transfer ink layer has an excessively high cohesion 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. A method of forming the product with the coating composition in the form of an aqueous dispersion is recommended as a technique that can easily avoid the above-described factors. The method of forming with the coating composition in the form of an aqueous dispersion can be performed as follows: (a) A heat transferable ink having high cohesive strength and melt viscosity can be easily formed as a functional layer that exhibits excellent printability. (B) By paying attention to the ionicity of the aqueous dispersion, various types of materials can be mixed and adjusted in an arbitrary ratio. (C) Thin film coating is easy. (D) Easy lamination coating. (E) The transferred image is sharply cut when heat is applied, and high density and relatively low energy heating printing is possible. This is because such advantages can be cited as advantages.

The thermal transfer ink layer of the present invention and, if necessary, various layers such as an adhesive layer are formed and coated by a known method such as a reverse roll coater method, an extrusion coater method, a gravure coater method, or a wire bar coating method. Technology can be adopted. The formed coating film thickness of the thermal transferable ink layer of the present invention,
Although not particularly limited, in the case of lamination on a smooth film, the thickness is generally 20 μm or less, preferably 15 μm or less, more preferably 3 to 10 μm. 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, when an adhesive layer is applied as necessary, the thickness of the adhesive layer is not limited, but is generally 5 μm or less, preferably 0.1 to 2 μm. Good range.

[0022]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In the examples and comparative examples,% and parts mean weight% and parts by weight, respectively. Comparative Example 1 3.5 μm coated with an adhesive layer of ethylene-vinyl acetate resin (vinyl acetate content 80%) having a thickness of 1 μm
On a support of a polyethylene terephthalate film having a thickness of m, a coating aqueous dispersion mixture composition for a thermal transferable ink layer described below was applied by a flow coater coating method so as to have a dry film thickness of 10 μm. ,
Thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen)
[A-1] 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-1] was converted to 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). Table 1 shows the results of the recording and printing tests. Comparative Example 2. A hot-melt type thermal transfer ink composition for a thermal transfer ink layer described below is applied to a support of a microporous non-woven fabric having a thickness of 20 μm to obtain a thermal transfer recording medium film thickness of 23 μm by an impregnation method. And a thermal transfer recording medium sample (8 mm wide ribbon-shaped specimen) [A
-2]. 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] was prepared using a thermal printer (a device having a built-in thermal head having a heating element density of 16 Dot / mm). Table 1 shows the results of recording and printing tests on commercially available plain paper.

Embodiment 1 FIG. On a support having the same adhesive layer as obtained in Comparative Example 1, an aqueous dispersion mixture composition for a thermal transferable ink layer having the following composition was coated by flow coater.
μm, and the thermal transfer recording medium sample (8
Thus, a ribbon-shaped specimen B) having a width of mm was obtained. Ethylene-ethyl acrylate copolymer resin: 10 parts Bis (2-hydroxyethyl) terephthalate 2-behenic acid adduct (purity 95-97%), synthetic ester having Shore D hardness of 58 (0 second value) at room temperature (Melting point: 86 to 89 ° 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 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 dots / mm). Are shown in Table 1. Embodiment 2. FIG. A thermal transfer recording medium sample (ribbon-shaped specimen having a width of 8 mm) C was obtained in the same manner except that the following crystalline esterified wax was used in place of the carnauba wax shown in Comparative Example 1. Synthetic esterified wax having a Shore D hardness of 50 (0 second value) at room temperature, which is a bis (2-hydroxyethyl) terephthalate 2-palmitic acid adduct (purity 97-99%) as a crystalline esterified wax ( 76-78 ° C). This thermal transfer recording medium sample C was transferred to a thermal printer (heating element density 16 Do).
t / mm thermal head)
Table 1 shows the results of recording and printing tests on commercially available plain paper.

Embodiment 3 FIG. A thermal transfer recording medium sample (8 mm) was prepared in the same manner except that the following crystalline esterified wax was used instead of the carnauba wax shown in Comparative Example 2.
A ribbon-shaped test specimen D) having a width was obtained. A synthetic esterified wax having a Shore D hardness of 52 (0 second value) at room temperature, which is bis (2-hydroxypropyl) terephthalate 2-stearic acid adduct (purity: 92 to 95%) as a crystalline esterified wax ( 74-79 ° C). Using a thermal printer (a device having a built-in thermal head with a heating element density of 16 Dot / mm), this thermal transfer recording medium sample D was subjected to a recording and printing test on commercially available plain paper, and the results are shown in Table 1. Example 4 Application of the following heat transfer ink layer on a 3.5 μm thick polyethylene terephthalate film support provided with a 1 μm thick ethylene-vinyl acetate resin (vinyl acetate content 80%) adhesive layer The aqueous dispersion mixture compositions (a) and (b) were coated with a dry film thickness of (a) by 10 μm + (2) using a flow coater coating method.
5 μm = 15 μm in total, to obtain a thermal transfer recording medium sample (a ribbon-shaped specimen having a width of 8 mm) E. (A) Coating aqueous dispersion mixed composition for thermal transfer ink layer Ethylene-ethyl acrylate copolymer resin having MI value of 150 gr on average: 10 parts bis (2-hydroxyethyl) terephthalate 2-palmitic acid as crystalline esterified wax The hardness of Shore D at room temperature, which is an adduct (purity 97-99%), is 50
(0 second value) synthetic esterified wax (melting point 76-
78 ° C, melt viscosity about 20 centipoise / 100 ° C): 6
5 parts Natural montan wax: 10 parts Carbon black: 15 parts (b) Aqueous 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 The hardness of Shore D at room temperature, which is bis (2-hydroxyethyl) terephthalate 2-palmitic acid adduct (purity 97-99%), is 50.
(0 second value) synthetic esterified wax (melting point 76-
78 ° C, melt viscosity about 20 centipoise / 100 ° C): 6
5 parts Natural montan wax: 10 parts Carbon black: 15 parts This thermal transfer recording medium sample E is 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). Table 1 shows the results of the test.

[0025]

[Table 1]

[0026]

As is clear from the results in Table 1 above,
The heat-sensitive transfer recording medium of the present invention was prepared using the samples B to E of Examples 1 to 4.
Compared with the results of Samples (A-1) and (A-2) of Comparative Examples 1 and 2, it was found that they exhibited print workability and print recordability that were not inferior (substantially equivalent). In all of the examples and comparative examples, printing of a transfer image without cuts or transfer defects was performed on plain paper having a Beck smoothness of 5 to 20. Also, 35
No blocking phenomenon was observed in each of the sample bodies stored by winding for a long time in an atmosphere of 65 ° C. and RH 65%. This is because, compared to the heat-sensitive transfer recording media of Comparative Examples 1 and 2 mainly containing carnauba wax, the heat-sensitive transfer recording media (ex. It has been found that it is possible to obtain (1) to (4). In the heat-sensitive transfer recording medium of the present invention, sufficient high printing workability and good storage stability are exhibited, and further, important physical properties such as high-resolution printing property and multiple-time printing property as needed, using carnauba wax. At least, the most important feature is that an excellent thermal transfer recording medium can be obtained.

Continuation of the front page (56) References JP-A-2-67186 (JP, A) JP-A-64-26494 (JP, A) JP-A-61-286199 (JP, A) JP-A-59-215891 (JP, A) JP-A-64-26495 (JP, A) JP-A-4-235947 (JP, A) JP-A-4-255393 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) B41M 5/38-5/40

Claims (6)

(57) [Claims] 1. A thermal 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 room temperature. The solid component is represented by the following general formula (1) or (2): R ₁ COO- (XO) _n -OC-Y-CO- (OX) _n -OOCR ₂ (1) R ₁ COO- (X- O) _n -OC-Y-CO- (OX) _n -OH (2) [wherein, X represents an alkylene group represented by an integer having 2 to 5 carbon atoms, Y represents a phenylene group, and R ₁ and R ₂ each represent a higher alkyl group or an alkenyl group represented by an integer having 12 to 30 carbon atoms, and n represents an integer of 1 to 50. A heat-sensitive transfer recording medium characterized by containing one or more kinds of mixtures selected from the group consisting of crystalline esterified waxes having a terephthalic acid skeleton in the range of 5 to 95% by weight. 2. In a thermal transfer recording medium comprising one or more thermal transferable ink layers formed on a support via an adhesive layer, any one or all of the thermal transferable ink layers may be used. A terephthalic acid skeleton represented by the general formula (1) or (2) according to claim 1, comprising a colorant and a solid solid component having a Shore D hardness of 45 or more at room temperature. A heat-sensitive transfer recording medium characterized in that one or more kinds selected from the group of crystalline esterified waxes are contained in the range of 5 to 95% by weight. 3. A heat-sensitive transfer recording medium comprising a heat-transferable ink layer formed on a support having microporous properties, wherein the heat-transferable ink layer comprises a colorant and a Shore A at room temperature.
A group of crystalline esterified waxes having a terephthalic acid skeleton represented by the general formula (1) or (2) according to claim 1, which comprises a solid solid component having a hardness of 45 or more. A heat-sensitive transfer recording medium, characterized in that one or two or more kinds of mixtures selected from the group consisting of 5 to 95% by weight are contained. 4. A terephthalic acid skeleton crystalline esterified wax represented by the general formula (1) or (2) according to claim 1 having a melting point of at least 65%. The thermal transfer recording medium according to any one of claims 1 to 3, wherein the temperature is in the range of -95 ° C. 5. A crystalline esterified wax having a terephthalic acid skeleton represented by the general formula (1) or (2) according to claim 1, wherein a 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-hydroxyethyl) terephthalate adduct of 1 or 2 behenic acid 1,2 stearic acid adduct of bis (2-hydroxypropyl) terephthalate, 1 or 2 palmitic acid adduct of bis (2-hydroxypropyl) terephthalate, 1 or 2 myristic acid addition of bis (2-hydroxypropyl) terephthalate Substance, bis (2-hydroxypropyl) teref 5. The thermal transfer recording medium according to claim 1, wherein the thermal transfer recording medium is a 1 or 2 behenic acid adduct of talate. 6. The solid component is one or more selected from the group consisting of a crystalline esterified wax having a terephthalic acid skeleton represented by the general formula (1) or (2) according to claim 1. 5 to 95% by weight, furthermore, at most 30% by weight of the following component (B) and / or at most 1
The heat-sensitive transfer recording material according to any one of claims 1 to 3, wherein 5% by weight is used in combination. (B) a group of heat-meltable substances such as animal waxes, plant waxes, mineral waxes, petroleum waxes, synthetic paraffin waxes, fatty acid amide waxes, polyester oligoester waxes, and oxidized or acid-modified denatured waxes (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 more mixtures of two or more styrene block copolymer resins such as isoprene-styrene block copolymer resins selected from the group of heat-fusible resin materials.