JPS62183384A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer recording medium capable of printing with high density and high quality even on a smooth paper and having excellent blocking resistance, by providing a plurality of layers having different compositions on a base while specifying the ratio of the thicknesses of the layers, and incorporating a coloring agent into the layer remote from the base. CONSTITUTION:Of two adjacent layers, a thermoplastic layer which is remote from a base is so arranged that a part thereof heated according to a recording pattern is plasticized and is adhered to the surface of a transfer recording paper. Other heat-fusible layer is so arranged that a part thereof being heated according to the recording pattern is melted to assist the thermoplastic layer in adhesion to the paper, whereas the non-heated part thereof prevents the thermoplastic layer from being easily adhered to the paper, by the adhesion thereof with the thermoplastic layer. A coloring agent to be used in the thermo plastic layer may be carbon black or an arbitrary one of inorganic pigments, organic pigments and organic dyes. The ratio of the thicknesses of the two layers is set in the range of 0.3-1.0, whereby the functions of the layers are sufficiently displayed, and favorable transferred patterns can be obtained for a wide range of paper qualities from a rough paper to a smooth paper.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a thermal transfer recording medium, and more specifically, it is capable of printing with high density and quality not only on papers with low surface smoothness, but also on paper with high surface smoothness, without background smudges, and with resistance to stain and blocking. Concerning an excellent thermal transfer recording medium.

[The weight of the invention]

In the thermal transfer recording method, it is known that the surface properties of the thermal transfer image receiving paper require a large color tube to be placed on the image6.
If the surface smoothness of the paper (paper) decreases, ink will not be able to enter the four parts, and the transfer rate will decrease (the image will stick). To improve this drawback, it is effective to increase the fluidity of heat-softening inks (make them easier to flow) when heated, but such inks need to have their softening point lowered to some extent. Ta. Currently, ink with a softening point of 60 to 80°C is used, and if ink with a softening point below this is used, it will cause the paper to deteriorate.
irJ blur (background stain) or image blurring occurred in the TIII image area. Another way to improve these shortcomings is to use support n knee +
It has been proposed that a release layer and an ink layer be sequentially applied to the paper, so that the so-called 284 Seisei paper can be printed on another paper with a high to 5 degree.6 However, this first trial Because the C soil ink R is scraped ~ IR4 up P7, there are transfer leaks, missing characters, etc. when printing on U7 paper.
However, it has the disadvantage that good quality printing cannot be obtained, and the printing quality on 11'N7 paper is by no means sufficient.

[Purpose of the invention]

An object of the present invention is to provide a thermal transfer recording medium that can print with high density and quality not only on paper with a rough surface but also on smooth paper, is free from scumming, and has excellent resistance to scratches and blocking. It is in.

An object of the present invention is to provide a thermal transfer recording medium having a plurality of layers having different compositions on a support, in which at least one of the plurality of scraps having different compositions is removed. For the adjacent 2M of Ill, this is achieved by setting the ratio of the thickness of the waste far from the support to the thickness of the layer close to the support to be 0.3 to 1.0, and by containing a colorant in the layer far from the support. It was done. That is, when printing with the thermal transfer recording medium of the present invention having a thickness ratio of 0.3 to 1.0, sharp printing can be performed on rough paper without chipping of the edges, and furthermore, when printing on smooth paper, Only the part that should be printed was transferred. In this way, when the ratio of the thicknesses of the two layers was 0.3 to 1.0, good printing was possible on any paper quality. : On the other hand, if the thickness ratio is less than 0.3, the sharpness of the print on rough paper will be poor or the characters will be missing, and if the ratio exceeds 1.0, the transfer of non-printed areas will occur on smooth paper. In both cases, high-quality printing cannot be obtained. The present invention will be explained in more detail below. In the present invention, among the adjacent 2JV1, the layer closer to the support is mainly composed of a heat-sensitive substance (hereinafter referred to as a heat-fusible layer), and the layer far from the support is mainly composed of a thermoplastic resin. (hereinafter referred to as a thermoplastic layer) is preferable. The function required of the thermoplastic layer is to plasticize and stick to the surface of the transfer paper in areas that are heated, depending on the recording pattern, and to not cause any adhesion to the transfer paper in areas that are not heated. In addition, it is required that the transfer paper can be torn cleanly in areas where it will stick and where it will not. The function of the heat-fusible layer is to help the thermoplastic layer adhere to the transfer paper layer by melting the heat in the areas that are heated, and to help the thermoplastic layer adhere to the transfer paper layer in the areas that are not heated, depending on the recording pattern described above. This prevents the thermoplastic 7M from being easily transferred to the receiving paper due to force. The present inventors have found that by setting the ratio of the thickness of the thermoplastic layer to the thickness of the thermofusible layer to be 0.3 to 1.0, the functions of the thermoplastic layer and the thermofusible layer are fully exhibited, It has been found that good transfer patterns can be obtained on a wide range of paper qualities, from paper to smooth paper. The heat-melting substances used in the present invention include substances that are solid or semi-solid at room temperature, and whose melting point (Yanagimoto MPJ
It is preferably a solid substance with a softening point (measured by Type-2) or a softening point (measured by ring and ball method) of 25 to 120'C, more preferably 40 to 120C. Examples include plant waxes such as carnauba wax, wood wax, auriculie wax, and esparto wax; animal waxes such as beeswax, insect wax, shellac wax, spermaceti wax; paraffin wax, microcrystalline wax, and ester 7-nox. In addition to waxes such as petroleum waxes such as , oxidized wax, mineral waxes such as montan wax, osikerite, and ceresin; higher fatty acids such as palutonic acid, stearic acid, malphosphoric acid, and behenic acid; palmityl Higher alcohols such as alcohol, stearyl alcohol, behenyl alcohol, marnyl alcohol, myricyl alcohol, eicosa/ol: cetyl palmitate, myricyl palmitate,
Higher fatty acid esters such as cetyl stearate and myricyl stearate; amides such as acetamine, propionic acid amide, palmitic acid amide, stearic acid amide, and amide wax; ether gum, rhodimaleic acid resin, ronone 7/-84 m, water Rosin derivatives such as added rosin; 7-ether resin, terpene resin, xylene resin, low molecular weight styrene resin, petroleum i? S resin, aromatic hydrocarbon resin, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, styrene-butanoene copolymer, styrene-ethylene-butylene copolymer,
Ionomer resin, polyamide resin, polyester resin, epoxy resin, polyurethane resin, acrylic resin, vinyl chloride 0I resin, cellulose resin, polyvinyl alcohol M4J (fat, styrene resin, imprene rubber, chloroprene) Items of rubber, natural rubber, etc.
compounds; higher amines such as stearylamine, behenylamine, and valmitylamine;
The [thermofusible solid component that is solid at room temperature] described in No. 68253 and the [vehicle] described in JP-A-55-105579 may also be used. These thermofusible substances can be easily converted into aqueous dispersion and are preferably used. These heat-melting substances can be used alone or in combination of two or more. In order to make a thermofusible substance into an aqueous dispersant, it may be emulsified in water by a known method such as a phase inversion method or a high pressure emulsification method in a system including emulsion removal. The emulsifier may be 7-ionic, anionic, cationic or amphoteric. In the present invention, the composition ratio of the components forming the heat-fusible layer is not limited; ) is preferred. Further, an Xf coloring material may be added to the heat-fusible layer as necessary. The machine used for coloring material is the total solid content of the heat-fusible layer Fit1
It is preferable that the amount is 20 parts by weight or less when compared to 00 parts by weight,
Delicious. The thermoplastic layer of the present invention may contain the above components, a thermoplastic resin, or various additives. For example, vegetable oils such as castor oil, linseed oil, olive oil,
Animal oils such as whale oil and mineral oils may be suitably used. In addition, 7-ionic surfactants, cationic surfactants,
Surfactants such as nonionic surfactants and amphoteric surfactants are also preferably used. The heat-fusible layer of the present invention may have a volume of 10 μl or more, more preferably 0.5 to 8 μl. As the thermoplastic resin used in the present invention, ester
Rosin derivatives such as rosin, maleic acid resin, rononphenol fat, hydrogenated rosin, phenolic 4jI11t
, terpene resins, xylene resins, petroleum resins, aromatic hydrocarbon resins, ionomer resins, polyester resins, polyamide resins, polyethylene/polypropylene resins, etc., and these can be easily dispersed in water by known methods. It is possible to make things into things. More preferred resins include acrylic resins. The acrylic resin contains at least one monobasic carboxylic acid such as acrylic acid or methacrylic acid or an ester thereof.
Obtained by emulsion polymerization of seeds with copolymerizable monomers. Examples of carboxylic acid monomers include methyl, ethyl, isopropyl, butyl, isobutyl, amyl, hexyl, octyl, 2-ethylhexyl, decyl, dodecyl, hydroxyethyl, and human mixypropyl esters of acrylic acid or methacrylic acid. In addition, monomers that can be copolymerized include vinyl acetate, vinyl chloride, vinylidene chloride, maleic anhydride, 7-maric anhydride, styrene, 2-methylstyrene, chlorostyrene, acrylonitrile, vinyltoluene, N-methylol acrylamide, N-methylol Examples include methacrylamide, N-butoxymethylacrylamide, tobutoxymethacrylamide, vinylpyridine, and N-vinylpyrrolidone, and one or more of these may be selected. Also preferred are tsene-based copolymers, such as emulsion polymers of tsene-based monomers such as butadiene, isoprene, imbutylene, and chloroprene and the above-mentioned copolymerizable monomers, such as butane-styrene, butane-styrene-vinylpyrinone, butanoene-7-pyrinone, etc. Examples include nitrile, chloroprene-styrene, and chloroprene-acrylonitrile. Further, more preferable resins include ethylene copolymers, such as ethylene-vinyl acetate, ethylene-ethyl acrylate, ethylene-methyl 7-tacrylate, ethylene-isobutyl acrylate, ethylene-acrylic acid, ethylene-vinyl alcohol, and ethylene-vinyl alcohol. Examples include copolymers of vinyl chloride and ethylene-acrylic acid metal salts. In addition, thermoplastic resins include polyurethane polymers and polyester polymers. The aqueous dispersion of a thermoplastic resin can be obtained by a method similar to that for producing an aqueous dispersion of a thermofusible substance, or by a conventional 7L specific gravity method. In the present invention, the composition ratio of the components forming the thermoplastic layer is not limited, but the colorant may be 5 to 40 parts by weight (more preferably 5 to 40 parts by weight) per 100 parts by weight of the total solid content of the thermoplastic layer.
35 parts by weight), and the thermoplastic substance is preferably used in an amount of 5 to 95 parts by weight (more preferably 10 to 90 parts by weight). In addition to the above components, the thermoplastic layer of the present invention contains various additives. For example, vegetable oils such as castor oil, linseed oil, and olive oil, animal oils such as whale oil, and mineral oils may be preferably used.Anionic, cationic, nonionic, and amphoteric surfactants are also suitable. The above-mentioned heat-melting substances are also suitably used.The coloring agent used in the plastic layer of the present invention is any one of six types of pigments, pigments, and organic dyes added to the carbon plastic layer. Examples of free pigments include titanium dioxide, zinc oxide, Prussian blue, tomium sulfide, iron oxides and chromates of lead, zinc, barium and calcium.Organic pigments include azo , thioinnovo,
Examples include anthodiquinone, anthurone, tri-7-ennooxan-based pigments, vat dye pigments, 7-thalocyanine pigments, such as; 1!7-lycyanine and derivatives thereof, and quinacridone pigments. Yes (Shige dyes include oxidation dyes, direct dyes, disperse dyes,
Examples include oil-soluble dyes and metal-containing oil-soluble dyes. The support used in the thermal transfer recording medium of the present invention preferably has heat-resistant strength, high dimensional stability, and high surface smoothness. Materials include, for example, paper such as transparent paper, capacitor paper, laminated paper, and coated paper, resin films such as polyethylene, polyethylene terephthalate, polystyrene, polypropylene, and polyimide, paper-resin film carriers, and aluminum foil. Metal sheets such as the above are preferably used. The thickness of the support is usually about 60 μs or less, especially 1.5 μs or less in order to obtain good thermal conductivity.
Preferably it is 15 μl. Furthermore, in the thermal transfer recording medium of the present invention, the structure on the back side of the support may be optional, and a backing layer such as an anti-sticking layer may be provided. In the thermal transfer recording medium of the present invention, techniques suitable for applying composition R1 comprising a heat-fusible layer and a thermoplastic layer to a support such as a polymeric film are well known in the art; The known techniques can also be applied to the present invention. For example, the constituent layers including the thermofusible layer and the thermoplastic layer are formed by aqueous coating of the aqueous dispersion composition (latex). As a coating method for the constituent layers including the heat-fusible Rη and the thermoplastic layer of the present invention, techniques such as a reverse roll coater method, an extrusion coater method, a gravure coater method, and a wire bar coating method can be employed. The thermoplastic layer of the present invention is 10 μl or less, more preferably 0.5 to 5 μl.
It suffices if it is μI. The thermal transfer recording medium of the present invention may have other constituent layers such as an undercoat WI (for example, a layer for adjusting film attachment) and an overcoat layer. A method for thermal printing using the thermal transfer recording medium of the present invention will be described below. The constituent layers of the thermal transfer recording medium of the present invention are stacked with a recording sheet such as paper, and the thermal transfer recording medium 11111 and/or Or apply energy from the recording sheet side. In other words, the thermoplastic layer is subjected to relatively low energy, so that the coloring agent and the like are transferred to the recording sheet together with the thermoplastic material.

【Example】

Examples are given below, but the embodiments of the present invention are not limited thereto. In addition, 1 part 1 used below indicates "part by weight." Example 1: (Table 1)
A heat-fusible layer was formed by changing the dry film as shown in Figure V. Rose 74 N7-/RiX (M!,!,','+70℃
) Aqueous dispersion 1 (solid content 30%) 95 parts Ethylene-vinyl acetate copolymer latex (vinyl acetate content 25f6 solid content 40%) 4 parts Surfactant (fluorine-based 2e!6 aqueous solution) 2 parts These heat-fusible layers The following thermoplastic layer coating 111 composition was applied using a wire bar and dried to form a thermal transfer record 12 K1.
A l-do sample was obtained. However, the dry film thickness was varied as shown in Table 1. 2-ethylhexyl acrylate-methyl/tafrylate-styrene copolymer latex (solid content 54 taro)
19 parts carbon blank water waste (solid content 32%) 10 parts surfactant (2% fluorine-based aqueous solution) 3 parts Person-1 Example 2 The following coating composition was applied to a 3.5μI/7 polyethylene terephthalate film-1- Using a wire bar, a heat-melting R film with a dry film thickness varied as shown in Table 2 was formed. Carnauba wax (melting point 80°C) aqueous dispersion (solid content 3
0%) 80 parts Ethylene-vinyl acetate copolymer latex (vinyl acetate content 25% solids content 40%) 16 parts surfactant (fluorine-based 2% water-soluble a) 2 parts heat-fusible layer A thermoplastic layer was coated with the coating composition using a wire bar so as to have a dry film thickness of *1 shown in Table 2 to prepare a thermal transfer recording medium sample. 2-ethylhexyl acrylate-styrene copolymer latex (solid content 42%) 18 parts ethylene-vinyl acetate copolymer latex (vinyl acetate amount 25% solid content 40)
%) 8 parts carbon black water waste (solid content 3
2%) 10 parts Surfactant (fluorine-based 2% aqueous solution) 3 parts*'1
5 Table-2 The kA thermal transfer recording medium samples obtained in Examples 1 and 2 were printed using a thermal printer (prototype machine equipped with a thin-film serial head with a heating cord density of 7 doL/yy) and printed with a printing panel of -1. 0 theory j/dot was printed on paper (Beck smoothness: 4 seconds) and shuttle paper (Beck smoothness: 100 seconds). The results are shown in Table-3. Table 3 Provides good printing on paper with both low and high surface smoothness.

Claims (1)

[Claims] In a thermal transfer recording medium having a plurality of layers having different compositions on a support, for at least one set of adjacent two layers among the plurality of layers having different compositions, the thickness of the layer farthest from the support is closer to the support. Ratio to layer thickness is 0.3-1
．． 0, and a layer far from the support contains a colorant.