JP3345702B2 - 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, and more particularly, to a thermal transfer recording medium suitable for use in a thermal transfer recording system using a thermal head.

[0002]

2. Description of the Related Art In a thermal transfer recording system, a thermal transfer ink layer of a thermal transfer recording medium comprising a base material and a thermal transfer ink layer provided on the surface thereof is brought into pressure contact with a transfer paper, and a thermal head is provided on the back surface of the base material. A pulsed signal current is sent to the head in the contacted state to heat the thermal head,
With this heat, the thermal transfer ink layer is melted or sublimated to print and record on the transfer receiving paper. By the way, conventionally, a plastic film such as polyethylene terephthalate has been widely used as a base material of a thermal transfer recording medium. The plastic film easily fuses to the thermal head during thermal transfer recording, and may cause a sticking phenomenon such as stopping the transport of the thermal transfer recording medium or breaking the thermal transfer recording medium. In order to prevent such a sticking phenomenon from occurring, various proposals have been made to provide a heat-resistant protective layer on the back surface of the base material (the surface in contact with the thermal head). For example, JP-A-55-7467, JP-A-60-201989, and JP-A-63-1
No. 72688 proposes to use a silicone resin, an epoxy resin, a melamine resin, a phenol resin, a fluororesin, an aromatic polyamide or the like as a heat-resistant protective layer. However, there is a drawback that lubrication is insufficient with these resins alone and sticking cannot be sufficiently prevented.

JP-A-61-143195 and the like have proposed the use of a silicone graft or a block acrylic copolymer as a heat-resistant protective layer, whereby sticking prevention is improved. There is a disadvantage that the film-forming property is insufficient, the heat-resistant protective layer may be peeled off from the substrate, and the heat-resistant protective layer is easily worn, which causes running failure of the thermal transfer recording medium. JP 1
JP-A-221281 and JP-A-1-234292 propose that a heat-resistant protective layer in which silicone oil is added to an ethylcellulose resin and a heat-resistant protective layer in which silicone oil is added to a cellulose ester resin containing an acetate group are proposed. The addition of silicone oil improves the lubricity of the heat-resistant protective layer and improves sticking prevention.However, the silicone component easily migrates to the surface of the thermal head, causing head dirt due to the silicone component and lowering print quality. There are drawbacks.

Japanese Patent Application Laid-Open No. 4-126294 proposes to provide a heat-resistant protective layer composed of a mixture of an acrylic silicone graft polymer and a reaction product of an amino-modified silicone oil and a polyfunctional isocyanate.
In this heat-resistant protective layer, the transfer of the silicone component to the surface of the thermal head is improved, but the film-forming properties of the acrylic component and the adhesiveness to the substrate are insufficient, and the heat-resistant protective layer peels off from the substrate, Further, the disadvantage of abrasion has not been sufficiently improved. JP-A-5-58067, JP-A-5-162472 and the like propose the use of a silicone polyvinyl butyral copolymer and a silicone-modified cellulose acetate phthalate as a heat-resistant protective layer, and the film formability is improved. However, there is a drawback that the heat resistance is insufficient and a hot melt adheres to the thermal head to deteriorate the printing quality.

Further, in the above-mentioned conventional techniques, in order to improve heat resistance and film formability, a crosslinking reaction with isocyanate, melamine, epoxide or the like is often performed by utilizing a hydroxyl group residue or the like in a resin. In addition, there are manufacturing defects such as the need for a curing step after the application of the heat-resistant protective layer, and the shortening of the pot life of the coating solution.

[0006]

The conventional thermal transfer recording medium having a heat-resistant protective layer does not sufficiently prevent the occurrence of sticking. Adhered to the thermal head to reduce the print quality of thermal transfer recording, or has the disadvantage that running failure occurs due to insufficient lubrication, peeling of the heat-resistant protective layer from the base material, or wear of the heat-resistant protective layer. Therefore, it has been difficult to obtain a thermal transfer recording medium in which all of these disadvantages have been solved.

Accordingly, an object of the present invention is to solve these problems, to prevent the occurrence of sticking sufficiently, and to adhere to the thermal head a heat-melted material from the heat-resistant protective layer or a residue caused by peeling or abrasion of the heat-resistant protective layer. An object of the present invention is to provide a thermal transfer recording medium which is prevented from being printed and has good printing quality and excellent running properties.

[0008]

[Means for solving the problem] Erasure

Erasure

[0010] erasure

Erasure

Erasure

It is another object of the present invention to provide a thermal transfer recording medium comprising a heat transfer ink layer provided on the surface of a substrate and a heat resistant protective layer provided on the back surface of the substrate in contact with the thermal head. -A layer mainly composed of a modified polymer consisting of a trunk polymer consisting of a polymer having active hydrogen except for a cellulose and a cellulose derivative, and a branch polymer consisting of a copolymer of a reactive silicone and a vinyl monomer. This is achieved by a thermal transfer recording medium.
Heat resistance mainly comprising a trunk polymer consisting of a polymer having active hydrogen except for cellulose and a cellulose derivative, and a modified copolymer consisting of a branch polymer consisting of a copolymer of a reactive silicone and a vinyl monomer. The protective layer has excellent heat resistance and lubricity, and has good film-forming properties and good adhesion to the substrate. By providing this heat-resistant protective layer on the back surface of the substrate that comes into contact with the thermal head, sticking may occur. Thermal transfer recording medium with excellent printing quality and excellent runnability by preventing heat melt from the heat-resistant protective layer or debris due to peeling or abrasion of the heat-resistant protective layer from adhering to the thermal head. Can be obtained.

Further, a modified copolymer comprising a trunk polymer comprising a polymer having active hydrogen except for cellulose and a cellulose derivative and a branched polymer comprising a copolymer of a reactive silicone and a vinyl monomer is used. By using as a main component, a heat-resistant protective layer having a film strength of 10 mN or more, a contact angle of pure water on the surface of 95 ° or more, and a dynamic friction coefficient of 0.07 or less can be obtained. The thermal transfer recording medium is particularly preferable because sticking prevention, print quality and running properties are further improved.

The polymer constituting the backbone polymer in the present invention has active hydrogen, and the function required for polymerization is that a radical copolymerization starting point can be formed by abstraction of hydrogen. Examples of such a polymer include polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polypropylene, polystyrene, vinyl chloride resin, vinyl chloride-vinyl acetate copolymer, and vinyl chloride acrylate copolymer. Coalesce, vinyl chloride acrylonitrile copolymer, ethylene vinyl chloride copolymer, polyvinyl alcohol, polyvinyl formal, polyvinyl acetoacetal, polyvinyl butyral, polyvinyl nitrate, polyvinyl ether, polyamide resin, polyimide, polyamide imide, polyester resin, Examples thereof include polycarbonate, polyacetal, and the like, and they may be used alone or in combination of two or more.

These polymers can be appropriately selected in consideration of polymerization reactivity, heat resistance as a heat-resistant protective layer, film formability, adhesiveness to a substrate, and the like, and polyvinyl acetoacetal and polyvinyl butyral are used. Polymerization reactivity, in terms of heat resistance as a heat-resistant protective layer, and among polyamide-based resins, N-methoxymethylated nylon is particularly preferable in terms of film-forming properties as a heat-resistant protective layer and adhesiveness to a substrate, By using these, the occurrence of sticking and the adhesion of the hot melt to the thermal head can be better prevented. The amount of the backbone polymer in the entire modified copolymer can be changed according to the polymerization reactivity, required heat resistance, film forming property, adhesion to the substrate, etc., but is 1 to 80% by weight, particularly 5% by weight. It is preferably in the range of ６０60% by weight.

The reactive silicone used in the modified copolymer is a silicone compound having a functional group such as an OH group or an epoxy group at one end, and a polyalkylsiloxane having a radically polymerizable unsaturated group at one end. There are compounds and the like, and the molecular weight is preferably about 100 to 50,000. These compounds can be used alone or
More than one kind may be used in combination, and in particular, by using a reactive silicone having a molecular weight of less than 500 and a reactive silicone having a molecular weight of 5,000 or more, the film strength does not decrease for a long time. The amount of the reactive silicone in the entire modified polymer is preferably in the range of 5 to 60% by weight, particularly preferably in the range of 10 to 40% by weight. When a reactive silicone having a molecular weight of less than 500 and a reactive silicone having a molecular weight of 5,000 or more are used in combination, the reactive silicone having a molecular weight of less than 500 is preferably 1 to 50% by weight, particularly preferably 5 to 30% by weight, and more preferably 5,000 or more. The content of the reactive silicone is preferably 0.5 to 30% by weight, particularly preferably 1 to 20% by weight.

The following are specific examples of the reactive silicone. That is, as the reactive silicone oil having a molecular weight of less than 500, those having a functional group such as an OH group, an epoxy group, an SH group, a COOH group, an unsaturated double bond at one end as shown in Tables 1 and 2, Further, a polydimethylsiloxane-based polymer reaction initiator as shown in Table 3 can also be used.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

[Table 3]

As the reactive silicone oil having a molecular weight of 5,000 or more, the reactive silicone oil (1) having L + M + N ≧ 61 and the reactive silicone oil (2) having N ≧
64, those in which N ≧ 65 in (3),
(4) N ≧ 65, (5) L
One that satisfies + M + N ≧ 63 and one that satisfies N ≧ 62 in (6) can be used.

The vinyl monomer used in the modified copolymer can be copolymerized with the backbone polymer and the reactive silicone. Specific examples thereof include methyl acrylate, ethyl acrylate, and n-butyl acrylate. , I-butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, methyl vinyl ether, ethyl vinyl ether , N
-Propyl vinyl ether, n-butyl vinyl ether,
i-butyl vinyl ether, styrene, α-methylstyrene, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxy Propyl acrylate, 2-hydroxypropyl methacrylate, allyl alcohol, glycidyl acrylate, glycidyl methacrylate, glycidyl allyl ether, acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, maleic anhydride, citraconic acid, acrylamide, methacrylamide, N -Methylol acrylamide, N-methylol methacrylamide, NN-dimethylacrylamide, NN-dimethylaminoethyl methacrylate, NN-diethylamino Methacrylate, vinyl monomers diacetone acrylamide. Further, silane coupling agents such as γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane can also be used. These monomers may be used alone or in combination of two or more.

The branched polymer in the modified copolymer has a large effect of improving heat resistance and preventing sticking, rather than the adhesion itself to the base material. In selecting a vinyl monomer, a glass at the homopolymer level is used. Transition point (Tg)
Is important, and the glass transition point at the homopolymer level is preferably 80 ° C. or higher. Particularly, methyl methacrylate (Tg: 105 ° C.), methacrylic acid (T
g: 130 ° C.) is also preferable from the viewpoint of copolymerization reactivity.
The amount of the vinyl monomer in the modified copolymer is 10 to 85.
% By weight is preferred. In addition, as the branch polymer,
Particularly, a silicone acrylic copolymer is preferable.

The modified copolymer in the present invention is usually produced by solution polymerization. For example, (1) by adding a reactive silicone and a vinyl monomer together with a polymerization initiator to a solution of a polymer having an active hydrogen under heating and stirring to cause a reaction, or (2) preparing a polymer having an active hydrogen. A polymer having active hydrogen is formed by introducing an unsaturated group into the united polymer, heating the solution of the polymer, and adding and reacting the reactive silicone and the vinyl monomer together with the polymerization initiator under stirring. It is possible to obtain a modified copolymer comprising a backbone polymer and a branched polymer comprising a copolymer of a reactive silicone and a vinyl monomer.

Examples of the solvent include aromatic hydrocarbon solvents such as toluene and xylene, acetone, methyl ethyl ketone,
A ketone solvent such as methyl isobutyl ketone, an ester solvent such as ethyl acetate and butyl acetate, an alcohol solvent such as ethanol and isopropanol, or a mixed solvent thereof can be used. As the polymerization initiator, benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, dicumyl peroxide, t-butyl peroxyisopropyl carbonate,
Oil-soluble polymerization initiators such as t-butyl perbenzoate, di-t-butyl peroxide, azobisisobutyronitrile, and azobisvaleronitrile can be used.

A method for graft-polymerizing a branch polymer to a backbone polymer comprising a polymer having active hydrogen includes the following:
There is a method based on a hydrogen abstraction reaction as in (1), and a method in which a graft active site is previously provided as in (2).
Regarding (1), a polymerization initiator having a large hydrogen abstracting action such as benzoyl peroxide, dicumyl peroxide, t-butylperoxyisopropyl carbonate, t-butylperbenzoate, di-t-butylperoxide or the like may be used. preferable. In the method (2), an unsaturated group is introduced into the OH group of the polyvinyl acetal with methacryloyl isocyanate, isocyanate ethyl methacrylate, or the like, or the OH group is esterified with maleic anhydride, itaconic anhydride, or the like. The method of introducing an unsaturated group into is effective.

As described above, a modified copolymer comprising a stem polymer comprising a polymer having active hydrogen except for cellulose and a cellulose derivative and a branch polymer comprising a copolymer of a reactive silicone and a vinyl monomer. The union can be produced without performing a crosslinking reaction with a crosslinking agent or the like, and has an advantage that a curing step after applying the heat-resistant protective layer is unnecessary and that there is no problem in terms of the pot life of the coating liquid. .
Furthermore, a heat-resistant protective layer having excellent film-forming properties, heat resistance, lubricity, and the like can be obtained without having a crosslinked structure by using the modified copolymer. The fact that this heat-resistant protective layer does not have a crosslinked structure can be confirmed by being soluble with toluene and / or methyl ethyl ketone.

The modified copolymer composed of the backbone polymer and the branched polymer composed of the copolymer of the reactive silicone and the vinyl monomer according to the present invention will be described with reference to the structural conceptual diagram shown in FIG. As shown in FIG. 1, since the silicone component 3 is chemically bonded to the vinyl polymer portion 2 of the branch polymer, the silicone component can be retained without causing head dirt due to transfer of the silicone component to the thermal head surface. Sticking can be sufficiently prevented by the lubricity and the releasability. Further, heat softening by the thermal head can be suppressed low due to the heat resistance of the vinyl polymer in the branch polymer, and adhesion of a hot melt to the surface of the thermal head can be prevented. Furthermore, the good film-forming properties of the trunk polymer and the adhesion to the substrate prevent the heat-resistant protective layer from peeling off from the substrate, and also prevent the heat-resistant protective layer from adhering debris to the thermal head. Is prevented.

As the heat-resistant protective layer in the present invention, a layer obtained by mixing the above-mentioned modified copolymer and a polymer having active hydrogen which is a main polymer component of the modified copolymer can be used. Thereby, the film strength of the heat-resistant protective layer can be further enhanced. Even if polyester, polyvinyl butyral, polyamide, etc. are mixed with ordinary silicone-modified acrylic resin, etc., the film strength is not improved due to poor compatibility. However, as in the present invention, the activity of the modified copolymer and its trunk polymer component By mixing with a polymer having hydrogen, the compatibility is greatly improved and the film strength can be increased. The mixing ratio between the heterocopolymer and the polymer having active hydrogen which is the backbone polymer component is 90:10 to 5
It is preferably in the range of 0:50. Further, as the polymer having active hydrogen, a polymer having high heat resistance is preferable, and a polymer having a glass transition temperature of 100 ° C. or more is particularly preferable from the viewpoint of preventing the hot melt from adhering to the surface of the thermal head.

Further, as the heat-resistant protective layer in the present invention, a layer obtained by mixing the above-mentioned modified copolymer with a modified silicone oil having a reactive functional group can be used. As a result, it is possible to prevent sticking from occurring and further prevent the hot melt from adhering to the thermal head surface. Examples of the functional group introduced into the modified silicone oil having a reactive functional group include methylstyrene, long-chain alkyl, polyether, carbinol, amine, epoxy, carboxyl, higher fatty acid, mercapto, methacryl, and the like. These modified silicone oils having a reactive functional group may be those into which one kind of functional group is introduced, or those into which two or more kinds of functional groups are introduced. The modified silicone oil having these reactive functional groups is appropriately selected in consideration of heat resistance, film formability, film strength, lubricity, and the like of the heat-resistant protective layer, in addition to preventing adhesion of a hot melt to the surface of the thermal head. be able to. Among them, amino-modified silicone oil and epoxy-modified silicone oil are particularly preferable in terms of film formability and film strength. The modified silicone oil has a reactive functional group equivalent of 5000.
mg / mol or less, particularly 1000 mg / mol or less.
Those which are not more than mg / mol are preferred.

The amount of the modified silicone oil having a reactive functional group to the modified copolymer is 3 to 6% by weight.
Is preferable. If the amount is large, the lubricity tends to be poor, and if the amount is small, the prevention of adhesion of the hot melt to the surface of the thermal head tends to be poor. In addition, the contact angle of pure heat on the surface of the heat-resistant protective layer made of the modified copolymer and the modified silicone oil having a reactive functional group is 110 ° or more, which prevents sticking and prevents hot melt on the thermal head surface. It is preferable from the viewpoint of preventing adhesion of scum and scum. Representative synthetic methods for the modified silicone oil include an equilibration reaction using an acid or alkali catalyst and an addition (or condensation) reaction with a silicone oil having Si—H.
Different synthesis methods are used depending on the type of organic group. Generally, the former is a preferable synthesis method including productivity.

In the present invention, to form the heat-resistant protective layer, a solution of the modified copolymer, a mixed solution of the modified copolymer and a polymer having active hydrogen which is a backbone polymer component of the modified copolymer, Alternatively, a mixed solution of a modified copolymer and a modified silicone oil having a reactive functional group or the like may be applied to the back surface of the substrate with a wire bar or the like, and dried. The thickness of the heat-resistant protective layer in the present invention is 0.01 to 2.00 μm.
Is preferred, and particularly preferably 0.04 to 0.6 μm.

The modified copolymer of the present invention is dissolved in a solvent such as methyl ethyl ketone, applied to the back surface of the substrate, and dried to form a heat-resistant protective layer. A structure can be formed. The microphase-separated structure is a state in which the block / graft polymer undergoes microphase separation in a solution to form stable micelles, and forms a microdomain structure in a coated solid state. With this structure, contradictory properties such as releasability and adhesiveness, heat resistance and mechanical strength can be provided.

The substrate in the thermal transfer recording medium of the present invention includes polycarbonate, polyarylate, polyetherimide, polysulfone, polyphenylether, polyamideimide, polyimide, polyethylene naphthalate, polyphenylsulfide, polyetheretherketone, and fluororesin. In addition to such films, polyethylene terephthalate, polybutylene terephthalate, polybutylene naphthalate, polyethylene, polypropylene,
Polystyrene, polyvinyl chloride, polyvinylidene chloride,
Films such as nylon can be used. Films having biaxial orientation are preferred. The thickness of the substrate is preferably 6 μm or less from the viewpoint of sensitivity in thermal transfer recording.

As the thermal transfer ink layer in the thermal transfer recording medium of the present invention, a conventionally known ink layer is used as it is, and is not particularly limited. That is, the thermal transfer ink layer used in the present invention is composed of a coloring agent, waxes, resins and additives such as a lubricant and a surfactant. In this case, as the coloring agent, for example, pigments such as carbon black, red bengala, Lele liquid C, fast sky blue, benzidine yellow, phthalocyanine green, phthalocyanine blue, direct dyes, oil dyes, basic dyes, and the like are used. .

Examples of the waxes include carnauba wax, olicury wax, candelilla wax, Japan wax, cane wax, montan wax, ozokerite, microcrystalline wax,
Examples include natural waxes such as ceresin wax and paraffin wax, and synthetic waxes such as Fischer-Tropsch wax, low molecular weight polyethylene, oxidized wax, and hydrogenated wax.

Examples of resins include polyacrylic acid, polyacrylate, polymethacrylic acid, and the like.
Polymethacrylic acid ester, polyacrylamide, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl pyrrolidone, polyvinyl chloride, vinyl resins such as polyvinylidene chloride, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxycellulose, hydroxypropyl cellulose,
Cellulose resins such as methylcellulose and cellulose acetate, polyester resins, polyacetal resins, epoxy resins, terpene resins, rosin resins, fluororesins, silicone resins, and the like. As additives, fatty acids, metal salts of fatty acids, fatty acid esters, fatty acid amides,
Inorganic salts, nonionic surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants and the like can be used, and are not particularly limited. The thermal transfer ink layer can be formed by a known method.

[0039]

Next, the present invention will be described more specifically with reference to examples and comparative examples. All parts, percentages, and ratios shown below are based on weight. Hereinafter, production examples of the modified copolymer according to the present invention will be described.

Production Example 1 A 500 ml flask equipped with a stirrer, a thermometer, a condenser and a nitrogen gas inlet tube was charged with 10 parts of Eslec KS-5 (trade name: polyvinyl acetal, manufactured by Sekisui Chemical Co., Ltd.) and 50 parts of methyl ethyl ketone. After the temperature was raised to 70 ° C. to dissolve, the mixture was cooled to 20 ° C., and 1 part of methacryloyl isocyanate was charged and reacted for 30 minutes to introduce an unsaturated double bond. 80 parts of toluene and 80 parts of ethanol were charged into the obtained unsaturated group-containing polyvinyl acetoacetal solution, and the temperature was raised to 70 ° C again. FM-0 prepared separately
725 (trade name: Reactive Silicone, manufactured by Chisso Corporation)
5 parts, 3-methacryloxypropyltris (trimethylsiloxy) silane (molecular weight: 422.
8) A mixed solution of 15 parts, 60 parts of methyl methacrylate, 10 parts of methacrylic acid, and 1 part of azobisisobutyronitrile was dropped by a dropping funnel over 2 hours, and then kept at the same temperature for 4 hours. Thus, a resin solution having a solid content of 32% was obtained. This is referred to as a resin liquid A.

Production Example 2 In Production Example 1, FM-0725 was mixed with 5 parts of AK-30 (trade name, reactive silicone, number average molecular weight, 30,000, manufactured by Toagosei Chemical Industry Co., Ltd.) and 3-methacryloxypropyltris (trimethylsiloxy). ) Silane is 1- (3
-Methacryloxypropyl) -1,1,3,3,3-pentamethyldisiloxane (molecular weight 274.5) A resin liquid having a solid content of 33% was obtained in the same manner as in Production Example 1 except that 15 parts were used. . This is referred to as a resin liquid B.

Production Example 3 Denka butyral # 600 was placed in the same flask as in Production Example 1.
20 parts of 0-C (trade name: polyvinyl butyral, manufactured by Denki Kagaku Kogyo Co., Ltd.), 80 parts of toluene, and 80 parts of butanol were charged and heated to 110 ° C. FM-07 prepared separately
21 (trade name: reactive silicone, molecular weight 5000, manufactured by Chisso Corporation), 10 parts, 3-methacryloxypropyltris (trimethylsiloxy) silane (molecular weight 422.
8) A mixed solution of 15 parts, 45 parts of methyl methacrylate, 10 parts of methacrylic acid, and 1 part of t-butylperoxyisopropyl carbonate was added dropwise over 2 hours.
The temperature was raised to 5 ° C. to complete the polymerization. This is referred to as a resin liquid C.

Production Example 4 100 parts of the resin A obtained in Production Example 1,
Then, 30 parts of -5, 35 parts of toluene and 35 parts of ethanol were charged and stirred for 1 hour to obtain a resin liquid having a solid content of 31%. This is referred to as a resin liquid D.

Production Example 5 Toresin F-30 (trade name: N-methoxymethylated nylon manufactured by Teikoku Chemical Industry Co., Ltd.) was placed in the same flask as in Production Example 1.
0 parts, methyl methacrylate 60 parts, AK-5 (trade name, manufactured by Toagosei Chemical Industry Co., Ltd .: silicon macromonomer, molecular weight: about 5000), 30 parts, BIC-75 (trade name, manufactured by Kayaku Akzo Co., Ltd .: t-butylperoxyisopropyl) (Carbonate) 0.5 part, toluene 10 parts, methyl alcohol 20 parts, cyclohexanone 10 parts were charged and reacted at 80 ° C. for 4 hours, and then a solution obtained by dissolving 0.05 parts of BIC-75 in 20 parts of toluene was added. The mixture was added and reacted at 80 ° C. for 4 hours. Thus, a milky white resin liquid was obtained. This is referred to as a resin liquid E.

Production Example 6 In the same flask as in Production Example 1, methyl ethyl ketone 200
And 10 parts of Esrec KS-5 were charged and heated to 70 ° C. to dissolve, treated in the same manner as in Production Example 1 using methacryloyl isocyanate, and then separately prepared FM-07
25 A mixed solution of 20 parts, 60 parts of methyl methacrylate, 10 parts of methacrylic acid, and 1 part of azobisisobutyronitrile was dropped over 2 hours, and the same operation as in Production Example 1 was performed to obtain a resin liquid having a solid content of 33%. Was. This is referred to as a resin liquid F.

Production Example 7 A resin liquid having a solid content of 33% was obtained in the same manner as in Production Example 6, except that FM-0725 was changed to 3-methacryloxypropyltris (trimethylsiloxy) silane. This is referred to as a resin liquid G.

Comparative Production Example 1 In the same flask as in Production Example 1, methyl ethyl ketone 200
Part was heated to 70 ° C., and AK-30 prepared separately was prepared.
35 parts, methyl methacrylate 55 parts, methacrylic acid 1
0 parts and 1 part of azobisisobutyronitrile were mixed with 2 parts.
The mixture was dropped over time to obtain a resin solution having a solid content of 34%. This is referred to as a resin liquid H.

Hereinafter, thermal transfer recording media of Examples and Comparative Examples of the present invention will be described. Example 1 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution A obtained in Production Example 1 and diluting the solution to a solid content of 4% was used to obtain a resin solution having a thickness of about 4.5 μm. Apply to the back of the terephthalate (PET) film with a wire bar, dry at 100 ° C. for 5 seconds,
A heat-resistant protective layer having a thickness of about 0.3 μm was formed. On the surface of the film, a dispersion of the following thermal transfer ink component was applied and dried to form a thermal transfer ink layer having an adhesion amount of about 2.8 g / m2, thereby obtaining a thermal transfer recording medium. Thermal transfer ink component Carnauba wax 6 parts Paraffin wax 8 parts Carbon black 4 parts Toluene 82 parts

Example 2 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution B obtained in Production Example 2 and diluting the solution to have a solid content of 4% was prepared to about 4.5 μm. Thick P
Apply to the back of the ET film with a wire bar,
For 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 3 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution C obtained in Production Example 3 and diluting the solution to have a solid content of 4% was added to a resin solution of about 4.5 μm. Thick P
Apply to the back of the ET film with a wire bar,
For 5 seconds to form a heat-resistant protective layer having a thickness of about 0.5 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 4 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution D obtained in Production Example 4 and diluting the resin solution to have a solid content of 4% was added to about 4.5 μm. Thick P
Apply to the back of the ET film with a wire bar,
For 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 5 In the resin solution E obtained in Production Example 5, methyl ethyl ketone / cyclohexanone / isopropyl alcohol (5/2 /
3) A resin solution obtained by adding a solvent and diluting the solid content to 4% was applied to the back surface of a PET film having a thickness of about 4.5 μm with a wire bar, and dried at 100 ° C. for 5 seconds.
A heat-resistant protective layer having a thickness of about 0.3 μm was formed. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 6 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution F obtained in Production Example 6 and diluting the solution to a solid content of 4% was added to a resin solution of about 4.5 μm. Thick P
Apply to the back of the ET film with a wire bar,
For 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 7 A resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution G obtained in Production Example 7 and diluting the resin solution to a solid content of 4% was added to a resin solution of about 4.5 μm. Thick P
Apply to the back of the ET film with a wire bar,
For 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 8 A carboxy-modified silicone was added to a resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution B obtained in Production Example 2 and diluting the solution to a solid content of 4%. Oil (functional group equivalent 2330mg / mol) 4% methyl ethyl ketone / cyclohexanone (9/1)
The solution was added at a ratio of 95: 5, and the solution was added to about 4.
A 5 μm thick PET film was coated on the back surface with a wire bar and dried at 100 ° C. for 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 9 An amino-modified silicone was added to a resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution B obtained in Production Example 2 and diluting the solution to a solid content of 4%. 4% of oil (functional group equivalent 1500mg / mol)
A methyl ethyl ketone / cyclohexanone (9/1) solution was added at a ratio of 95: 5, and the solution was added to about 4.5 μm.
Apply to the back side of the PET film of m thickness with a wire bar,
After drying at 100 ° C. for 5 seconds, a heat-resistant protective layer having a thickness of about 0.3 μm was formed. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Example 10 An amino-modified silicone was added to a resin solution obtained by adding a methyl ethyl ketone / cyclohexanone (9/1) solvent to the resin solution B obtained in Production Example 2 and diluting the solution to a solid content of 4%. A 4% solution of oil (functional group equivalent: 840 mg / mol) in methyl ethyl ketone / cyclohexanone (9/1) was added in a ratio of 95: 5, and the solution was added to about 4.5 μm.
Apply to the back side of the thick PET film with a wire bar,
After drying at 00 ° C. for 5 seconds, a heat-resistant protective layer having a thickness of about 0.3 μm was formed. In addition, the surface of the film was provided with Example 1
In the same manner as in the above, a thermal transfer ink layer was provided to obtain a thermal transfer recording medium.

Comparative Example 1 A resin solution obtained by adding methyl ethyl ketone to the resin solution H obtained in Comparative Production Example 1 and diluting the solid content to 4% was applied to the back surface of a PET film having a thickness of about 4.5 μm. The composition was applied with a wire bar and dried at 100 ° C. for 5 seconds to form a heat-resistant protective layer having a thickness of about 0.3 μm. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

COMPARATIVE EXAMPLE 2 A 4% solution of polyvinyl acetoacetal / alcohol-modified silicone oil (90/10) in 4% methyl ethyl ketone / toluene (5/5) was applied to the back of a PET film having a thickness of about 4.5 μm using a wire bar. After drying at 100 ° C. for 5 seconds, a heat-resistant protective layer having a thickness of about 0.3 μm was formed. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

Comparative Example 3 The resin solution H obtained in Comparative Production Example 1 and a 5% solution of KS-5 (polyvinyl acetal) in methyl ethyl ketone were diluted with methyl ethyl ketone to a solid content ratio of 80/20 to obtain a total solid content of 4%. Was obtained. This was applied to the back of a PET film having a thickness of about 4.5 μm with a wire bar,
After drying at 5 ° C. for 5 seconds, a heat-resistant protective layer having a thickness of about 0.3 μm was formed. Further, a thermal transfer ink layer was provided on the surface of the film in the same manner as in Example 1 to obtain a thermal transfer recording medium.

For the thermal transfer recording media obtained in the above Examples and Comparative Examples, the film strength of the heat-resistant lubricating protective layer, the contact angle of the surface of the heat-resistant lubricating protective layer with pure water, and the coefficient of dynamic friction were measured by the methods described above. . Table 4 shows the measurement results.
Show. Printing was performed using the thermal transfer recording media obtained in Examples and Comparative Examples, and anti-sticking properties, stains on the thermal head [presence or absence of hot melt adhesion to the thermal head surface (hot melt adhesion), and Presence or absence of physically detached residue on the thermal head surface (adhered residue)]
Was evaluated. Table 5 shows the evaluation results. The printing method and evaluation criteria are as shown below.

(1) Anti-sticking property Thermal transfer printing was performed under the following printing conditions, and the occurrence of wrinkles due to sticking and the occurrence of stick sounds were evaluated. Printing conditions: Thermal head: Thin film line thermal head (density 8 / mm) (manufactured by Kyocera) Applied energy: 25 mJ / mm2 Printing speed: 50 mm / sec Platen pressing: 350 gf / cm Receiving paper: White PET (manufactured by Lintec) Print pattern: CODE39 horizontal barcode (Narr
ow 2: Wide 5dot) Cord width 30mm Length about 40mm

(2) Thermal Head Stainability Under the above printing conditions, thermal transfer printing was performed continuously over 100 m using a CODE 39 vertical bar code (Narrow 2: Wide 6 dot) as a printing pattern, and the heat-melted material adhered to the heating element of the thermal head. The presence or absence of heat (adhesion of a hot melt) and the presence or absence of the physically detached residue on the thermal head heating element (adhesion of residue) were confirmed and evaluated.

[0064]

[Table 4]

[0065]

[Table 5]

As is apparent from Table 5, sticking is sufficiently prevented in the thermal transfer recording medium of the present invention, and a heat melt from the heat-resistant protective layer or scum due to abrasion of the heat-resistant protective layer adheres to the thermal head. Is prevented,
The printing quality was good. Further, the thermal transfer recording medium of the example was excellent also in running property.

[0067]

According to the present invention, the occurrence of sticking is sufficiently prevented, and the heat-melted material from the heat-resistant protective layer or the debris due to peeling or abrasion of the heat-resistant protective layer is prevented from adhering to the thermal head. It is possible to obtain a thermal transfer recording medium which is excellent in printing quality and good in lubricity, has little peeling of the heat-resistant protective layer from the substrate and wear of the heat-resistant protective layer and is excellent in running properties.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating the configuration of a modified polymer that is a main component of a heat-resistant lubricous protective layer according to the present invention.

[Explanation of symbols]

 1 backbone polymer 2 vinyl polymer part in branch polymer 3 silicone part in branch polymer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Iwaki 8-3 Ninocho, Mizuho-ku, Nagoya-shi, Aichi Natoko Paint Co., Ltd. (72) Inventor Shigekazu Teranishi 8 Ninocho, Mizuho-ku, Nagoya-shi, Aichi -3 Inside Natco Paint Co., Ltd. (72) Susumu Kawakami 8-3 Ninocho, Mizuho-ku, Nagoya City, Aichi Prefecture Inside Natco Paint Co., Ltd. (72) Hironori Hata 8 Ninomachi, Mizuho-ku, Nagoya City, Aichi Prefecture -3 NATCO PAINT CORPORATION (56) References JP-A-6-270561 (JP, A) JP-A-2-299886 (JP, A) JP-A-2-235693 (JP, A) JP-A-1 JP-A-214475 (JP, A) JP-A-2-274596 (JP, A) JP-A-2-102096 (JP, A) JP-A-62-20082 (JP, A) JP-A-4-126294 (JP, A) JP-A-5-177963 (J P, A) JP-A-62-1575 (JP, A) JP-A-3-155987 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (13)

(57) [Claims] 1. A thermal transfer recording medium comprising: a heat transfer ink layer provided on the surface of a substrate; and a heat resistant protective layer provided on the back surface of the substrate in contact with the thermal head.
The main layer is a trunk polymer composed of a polymer having active hydrogen except for a polymer and a cellulose derivative, and a modified copolymer composed of a branch polymer composed of a copolymer of a reactive silicone and a vinyl monomer. A thermal transfer recording medium characterized by the above-mentioned. 2. A thermal transfer recording medium according to claim 1, wherein the polymer having active hydrogen is polyvinyl acetal or polyvinyl butyral. 3. The polymer having active hydrogen is N-methoxy.
2. The method according to claim 1, wherein the nylon is a cymethylated nylon.
Thermal transfer recording medium . 4. Any branch polymer of claims 1 to 3, wherein the silicone-acrylic copolymer
In a thermal transfer recording medium or. 5. The method according to claim 1, wherein the proportion of the reactive silicone in the modified copolymer is 5 to 60% by weight.
A thermal transfer recording medium according to any one of claims 1 to 4 . 6. The reactive silicone in the branch polymer has a molecular weight of less than 500 and a reactive silicone having a molecular weight of less than 500.
The thermal transfer recording medium according to any one of claims 1 to 5, comprising the reactive silicone. 7. A heat-resistant protective layer is modified copolymer and cellulose - Graphics and claims 1 to 6 SL, characterized in that a mixture of polymers having an active hydrogen with the exception of a cellulose derivative
The thermal transfer recording medium is any one of the mounting. 8. The thermal transfer recording medium according to claim 7, wherein the polymer having active hydrogen has a glass transition temperature of 100 ° C. or higher. 9. Thermal <br/> transfer heat resistant protective layer is any one of claims 1 to 6 further characterized in that comprises a mixture of modified silicone oil having a reactive functional group and the modified copolymer recoding media. 10. The thermal transfer recording medium according to claim 9, wherein the modified silicone oil has a reactive functional group equivalent of 5000 mg / mol or less. 11. The thermal transfer recording medium according to claim 9, wherein the reactive functional group of the modified silicone oil is an amino group or an epoxy group. 12. The heat-resistant protective layer has a film strength of 10 mN or more,
The contact angle of the surface of the heat-resistant protective layer to pure water is 95 ° or more, and the dynamic friction coefficient is 0.07 or less.
12. A thermal transfer recording medium according to any one of 1 to 11 . 13. The method according to claim 9, wherein a contact angle of the surface of the heat-resistant protective layer with respect to pure water is 110 ° or more.
Or the thermal transfer recording medium according to 11.