JPH0342594B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a thermal transfer recording medium, and more specifically, a thermal transfer recording medium that can prevent peeling of a heat-fusible coloring material layer and can be suitably used for multiple printing. Regarding recording media.

[Prior Art] Conventionally, as an adhesive layer interposed between a support and a heat-fusible coloring material layer, polyester resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, vinyl chloride resin (Japanese Patent Application Laid-open No. 55 -105579), polyamide resin (see JP-A-56-116193),
It is disclosed that polyvinyl butyral resin, epoxy resin (see JP-A-57-36698), and saturated linear polyester resin (see JP-A-59-96992) are used.

[Problems to be Solved by the Invention] However, since conventional heat-melting coloring material layers use compounds with relatively low polarity such as wax and higher fatty acids as main components, polyester resins, polyester resins, etc. are used as supports. When using a polymer film with relatively high polarity such as polyimide resin, if an adhesive material with relatively high polarity such as polyvinyl butyral resin, epoxy resin, or polyester resin is used for the adhesive layer, the adhesion to the support will be reduced. Although the strength is strong, the adhesive force with the coloring material layer is weak, and the film is likely to peel off at the interface between the coloring material layer and the adhesive layer, making it difficult to print multiple times. This becomes especially noticeable when the applied power is increased or when additives such as surfactants are mixed into the coloring material layer.

In addition, if an ethylene-ethyl acrylate copolymer or an ethylene-vinyl acetate copolymer is used as the composition of the adhesive layer, a sufficiently high adhesive property can be obtained, but the adhesive layer becomes sticky at room temperature after being applied and dried. When a heat-fusible coloring material layer is applied thereon, problems such as uneven coating and unevenness in the transferred image are likely to occur.

Furthermore, in terms of factory production technology, special equipment such as non-contact transfer equipment is required, leading to high production costs.

Therefore, the present invention can strengthen the adhesive force between the support and the coloring material layer and prevent the coloring material layer from peeling, especially when the applied power is increased or when additives such as surfactants are mixed. Even in cases where the above-mentioned film peels off, stable and good printing can be obtained multiple times, and furthermore, the adhesive strength after coating and drying does not become sticky at room temperature, so that the heat-melting color material layer on top of it can be easily printed. It is an object of the present invention to provide a heat-sensitive transfer recording medium that is easy to apply and can provide an even transfer image.

[Means for Solving the Problem] As a result of intensive research, the present inventor has discovered that in a thermal transfer recording medium having a heat-melting coloring material layer on a support via an adhesive layer, ethylene is added to the adhesive layer. - at least one polymer compound selected from ethyl acrylate, ethylene-vinyl acetate, vinyl chloride-vinyl acetate, and polyurethane resin (hereinafter referred to as the polymer compound of the present invention), and behenic acid, ester wax, and By containing at least one compound selected from α-olefin-maleic anhydride copolymers (hereinafter referred to as the compound of the present invention), the above technical problem is solved and the object of the present invention is achieved. find out that it will be done,
This led to the present invention.

The present invention will be explained in detail below.

The thermal transfer recording medium of the present invention has an adhesive layer formed on a support, and one or more heat-melting coloring material layers formed thereon. Note that when two or more coloring material layers are formed, an intermediate layer may be provided between each coloring material layer.

The adhesive layer of the present invention basically consists of the compound of the present invention and the polymer compound of the present invention, and may contain other substances as necessary.

The compound of the present invention used in the adhesive layer of the present invention is:
One or more of the above compounds can be arbitrarily selected and used in combination, and it is particularly preferable to select and use the same compound as one of the low melting point substances contained in the heat-melting coloring material layer described below. That's true.

As for the physical properties of the polymer compound of the present invention, it is preferable that the melting point (value measured by Yanagimoto, MPJ-2 type) or softening point (value measured by ring and ball method) is 40°C or higher;
More preferably, the temperature is 60°C or higher.

The composition ratio of the compound of the present invention and the polymer compound of the present invention constituting the adhesive layer in the present invention is such that the compound of the present invention is 2 to 2.
Preferably 50%, more preferably 5-40
%, and the polymer compound of the present invention preferably accounts for 50 to 98%, more preferably 60 to 95%.
In terms of strengthening the adhesion with the support, it is preferable that the polymer compound of the present invention accounts for 50% or more, while in terms of adhesion and stickiness with the coloring material layer, it is preferably 98%.
It is preferable that it is below.

Examples of combinations of the compound of the present invention and the polymer compound of the present invention used in the thermal transfer recording medium of the present invention include: polyurethane resin-behenic acid ethylene-vinyl acetate copolymer-maleic anhydride-olefin copolymer ethylene-vinyl acetate Copolymer - polyester resin - ester wax Ethylene - vinyl acetate copolymer - polyurethane resin - behenic acid Ethylene - vinyl acetate copolymer - phenoxy resin - behenyl alcohol Ethylene - vinyl acetate copolymer - ester wax - behenic acid, etc. can be mentioned.

Examples of substances other than the above-mentioned compounds of the present invention and polymeric compounds of the present invention that are optionally contained in the adhesive layer of the present invention include surfactants and the like.

Methods for forming the adhesive layer of the present invention on a support include, for example, a hot melt coating method and a solvent coating method, and coating methods include a reverse roll coater method, an extrusion coater method, a gravure coater method, and a wire bar coater method. Law etc. will be adopted. The thickness of the adhesive layer formed by the above method is preferably 0.1 to 3 μm, more preferably 0.3 to 1 μm.

As the heat-melting coloring material layer coated on the adhesive layer of the present invention, various heat-melting coloring material layers can be used without particular limitation, but the following heat-melting coloring material layers are preferably used. I will explain about it.

The heat-fusible substance used in the heat-fusible coloring material layer in the present invention is a low-melting substance that is solid at room temperature and reversibly becomes a liquid phase upon heating. Specific examples include carnauba wax, wood wax, Plant waxes such as auricilla wax and esparturo,
Animal waxes such as beeswax, insect wax, serrata wax, spermaceti wax, petroleum waxes such as paraffin wax, microcrystalline wax, ester wax, oxidized wax, mineral waxes such as montan wax, ozokerite, ceresin, olefin-maleic anhydride In addition to waxes such as synthetic waxes such as copolymers; higher fatty acids such as palmitic acid, stearic acid, marigalic acid, and behenic acid; palmityl alcohol, stearyl alcohol, behenyl alcohol, marganyl alcohol, myricyl alcohol, eicosanol, etc. higher alcohol; higher fatty acid esters such as cetyl palmitate, myricyl palmitate, cetyl stearate, miticyl stearate; acetamide, propionic acid amide, palmitic acid amide, stearic acid amide,
Examples include amides such as amide waxes, which may be used alone or in combination.
Among these, higher amides such as palmitic acid amide, stearic acid amide, oleic acid amide, and amide wax are particularly preferred. Also, JP-A-54-
The "thermofusible solid component that is solid at room temperature" described in Japanese Patent No. 68253 may be used.

The heat-melting color material layer of the present invention may contain a surfactant. The surfactant may be any of nonionic surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants, etc., such as polyethylene glycol, polyethylene glycol monoester, polyethylene glycol diester, polyoxy Nonionic surfactants such as ethylene sorbitan ester, polyoxyethylene alkyl ether, polyoxyethylene nonyl phenyl ether, and polyglycerin ester: octadecylamine acetate,
Cationic surfactants such as alkyltrimethylammonium chloride, polyoxyethylene octadecylamine, polyoxyethylene alkylamine, and polymeric amines: fat-produced soda soap, fatty acid potassium soap, stearate soap, alkyl ether sulfate (Na salt), Matsukou alcohol, sulfuric acid ester sodium salt, sodium dodecylbenzene sulfonate, sodium normandodecylbenzene sulfonate (soft type), sodium alkylmethyl taurate, sodium oleoyl methyl taurate, sodium dioctyl sulfosuccinate, polymer type Anionic surfactants such as anions (polycarboxylic acid type): Examples include amphoteric surfactants such as hydroxyethylimidazoline sulfate, imidazoline sulfonic acid, and alkylamino acids.

The colorant used in the heat-melting color material layer of the present invention may be appropriately selected from various pigments, and is preferably a direct dye, an acid dye, a basic dye, a disperse dye, an oil-soluble dye (a metal-containing oil-soluble (including dyes), etc. The coloring matter used in the coloring material layer of the present invention may be any pigment that can be transferred (transferred) together with the heat-melting substance, and may be a pigment in addition to the above. In addition, specifically, the following can be mentioned. That is, as yellow pigments, Kayalon Polyester Light Yellow 5G-S (Nippon Kayaku), Oil Yellow S-7 (white clay), Eisen Spiron Yellow GRH Special (Hodogaya), Sumiplast Yellow FG (Sumitomo), Eisen Spiron Yellow GRH (Hodogaya), etc. are preferably used.
Red pigments include Diaceriton Fastred R (Mitsubishi Kasei), Dianics Brilliant Red BS-E (Mitsubishi Kasei), and Sumiplast FB.
(Sumitomo), Sumiplastrets HFG (Sumitomo), Kayalon Polyester Pink RCL-E (Nippon Kayaku),
Eisen Spiron Red GEH Special (Hodogaya), etc. are preferably used. As a blue pigment,
Diaceriton Fast Brilliant Blue R
(Mitsubishi Kasei), Dianex Blue EB-E (Mitsubishi Kasei), Kayalon Polyester Blue B-SF Conc (Nippon Kayaku), Sumiplast Blue 3R (Sumitomo),
Sumiplast Blue G (Sumitomo) and the like are preferably used. Also, as a yellow pigment, Hansa Yellow
3G, Tartrazine Lake, etc. are used, red pigments include Brilliant Carmine FB-Piure (Sanyo Color), brilliant carmine 6B (Sanyo Color), Alizarin Lake, etc., and blue pigments include Cerulean Blue, Sumika, etc. Print cyanine blue GN-O (Sumitomo), phthalocyanine blue, etc. are used, and as the black pigment, carbon black, oil black, etc. are used. Among these, carbon black is preferably used.

The composition ratio of the heat-fusible coloring material layer of the present invention is not limited, but the content of the heat-fusible substance is 30 to 95 parts per 100 parts (parts by weight, same hereinafter) of the total solid content of the heat-fusible coloring material layer.
parts (more preferably 40 to 90 parts), colorant 5 to 40 parts
part (more preferably 10 to 35 parts), surfactant is 0
The amount is preferably 60 parts to 60 parts (more preferably 5 to 50 parts).

In addition to the above-mentioned components, the heat-melting coloring material layer of the present invention includes:
The adhesive layer may contain a polymer compound similar to the polymer compound contained in the adhesive layer, various additives (for example, vegetable oils such as castor oil, linseed oil, and olive oil, animal oils such as whale oil, and mineral oils).

The heat-melting coloring material layer of the present invention is coated on the adhesive layer in the same manner as the adhesive layer described above, and has a thickness of 3 to 3.
The thickness is preferably 50 μm, more preferably 5 μm.
It is sufficient if it is set to ~20 μm. In addition, in the case of a multilayer configuration,
The thickness of the coloring material layer may be sufficient for one thermal transfer, or may be sufficient for multiple thermal transfers.

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. Examples of materials include papers such as plain paper, condenser paper, laminated paper, and coated paper; resin films such as polyethylene, polyethylene terephthalate, polystyrene, polypropylene, and polyimide; and paper.
A resin film composite, a metal sheet such as aluminum foil, etc. are all suitably used. The thickness of the support is usually about 60 μm or less, preferably 1 to 25 μm, more preferably 1.5 to 15 μm, in order to obtain good thermal conductivity.
Particularly preferably, the thickness is in the range of 1.5 to 8 μm. The thermal transfer recording medium of the present invention may have an overcoat layer (for example, a protective layer), and the structure on the back side of the support is arbitrary.
A backing layer such as an anti-stacking layer may also be provided.

[Example] Examples will be given below, but the present invention is not limited thereto. In addition, "part" used below
indicates "parts by weight".

Example 1 The following composition was applied onto a 3.5 μm thick polyethylene terephthalate film using a wire bar and dried with air at 80°C. In this way, an adhesive layer with a dry thickness of 0.8 μm was obtained. This adhesive layer was a good layer with no stickiness.

Polyurethane resin (manufactured by Nippon Polyurethane Co., Ltd. N-
2304) 4 parts Behenic acid 0.8 parts Tetrahydrofuran 95.2 parts Next, Composition A below was subjected to a dispersion treatment at 100° C. for 4 hours using a sand grinder to obtain a dispersion.

[Composition A] Carbon black 15 parts Paraffin wax (SP0145 manufactured by Nippon Seiro Co., Ltd.)
40 parts carnauba wax (manufactured by Nikko Fine Products) 20 parts polyethylene glycol (average molecular weight 4000) 15 parts ethylene-vinyl acetate copolymer (NUC3160 manufactured by Nippon Unicar Co., Ltd.) 10 parts This dispersion was placed on the adhesive layer above. Hot-melt coating was performed using a wire bar to obtain a thermal transfer recording medium sample of the present invention having a heat-melt coloring material layer with a film thickness of 8.0 μm.

Print this using a serial type thermal printer at 0.6
Solid black printing was performed by applying energy of mJ/dot. After printing once, align the thermal head and use the same part of the recording medium.
Repeated printing was performed three times. At this time, printing was performed using high-quality paper with a Beck smoothness of 100 sec as the transfer paper.

As a result, as shown in FIG. 1, there was no film peeling at all, there was little decrease in density even after printing three times, and even printing with high density was obtained.

Example 2 The following composition was applied onto a 3.5 μm thick polyethylene terephthalate film using a wire bar and dried with air at 80°C. In this way, an adhesive layer with a dry thickness of 0.8 μm was obtained. This adhesive layer was a good layer with no stickiness.

Ethylene-vinyl acetate copolymer (NUC3185, manufactured by Nippon Unicar Co., Ltd.) 4.0 parts Maleic anhydride-olefin copolymer (Diakaruna 30, manufactured by Mitsubishi Kasei Corporation) 0.8 parts Xylene 95.2 parts Next, the following composition B was mixed using a sand grinder. Dispersion treatment was performed at 100°C for 4 hours to obtain a dispersion.

[Composition B]

Carbon black 15 parts paraffin wax (SP0145 manufactured by Nippon Seirosha)
40 parts maleic anhydride-olefin copolymer (Diakaruna 30 manufactured by Mitsubishi Kasei Corporation) 35 parts ethylene-vinyl acetate copolymer (NUC3160 manufactured by Nippon Unicar Co., Ltd.) 10 parts This dispersion was bonded as described above in the same manner as in Example 1. A sample of the heat-sensitive transfer recording medium of the present invention having a heat-melting coloring material layer with a thickness of 8.0 μm was obtained by coating on the layer.

This was printed in solid black in the same manner as in Example 1.

As a result, as shown in FIG. 1, there was no film peeling at all, there was little decrease in density even after printing three times, and even printing with high density was obtained.

Comparative Example 1 The following composition was applied onto a 3.5 μm thick polyethylene terephthalate film using a wire bar, and dried with air at 80°C. In this way, an adhesive layer with a dry thickness of 0.8 μm was obtained.

Polyester resin (Byron-200 manufactured by Toyobo Co., Ltd.)
4 parts Methyl ethyl ketone 26 parts Xylene 70 parts On this adhesive layer, a heat-melting color material layer having the same composition as in Example 1 was coated to a thickness of 8.0 μm to obtain a thermal transfer recording medium sample.

As in Example 1, solid black printing was attempted many times.

As a result, as shown in FIG. 1, the amount of transfer in the first printing was large, and the density of printing in the second printing decreased rapidly, resulting in a thermal transfer recording medium with poor multi-printing performance.

Comparative Example 2 The following composition was applied onto a 3.5 μm thick polyethylene terephthalate film using a wire bar and dried with air at 80°C. In this way, an adhesive layer with a dry thickness of 0.8 μm was obtained.

Polyurethane resin (manufactured by Nippon Polyurethane Co., Ltd. N-
2304) 4 parts Tetrahydrofuran 96 parts On this adhesive layer, a heat-melting coloring material layer having the same composition as in Example 1 was coated to a thickness of 8.0 μm to obtain a heat-sensitive transfer recording medium.

As in Example 1, solid black printing was attempted many times.

As a result, as shown in FIG. 1, the amount of transfer in the first printing was large, and the density of printing in the second printing decreased rapidly, resulting in a thermal transfer recording medium with poor multi-printing properties.

Comparative Example 3 The following composition was applied onto a 3.5 μm thick polyethylene terephthalate film using a wire bar and dried with air at 80°C. In this way, an adhesive layer with a dry thickness of 0.8 μm was obtained. This adhesive layer was a slightly sticky layer.

Ethylene-vinyl acetate copolymer (NUC3185 manufactured by Nippon Unicar Co., Ltd.) 4.0 parts Xylene 96 parts A heat-melting coloring material layer having the same composition as in Example 3 was coated on this adhesive layer to a film thickness of 8.0 μm. A thermal transfer recording medium was obtained.

As in Example 2, solid black printing was attempted many times.

As a result, as shown in FIG. 1, printing was possible three times, but density unevenness was observed in the resulting image.

In addition, in the above Examples 1 and 2, the applied power
When experiments were conducted on a thermal transfer recording medium with the only difference being that the energy was changed to 0.9 mJ/dot, the same results as in Examples 1 and 2 were obtained.

[Effects of the Invention] According to the present invention, by strengthening the adhesive layer between the support and the coloring material layer and preventing film peeling, stable printing is possible multiple times, and the adhesive layer is coated. Since there is no stickiness after drying, it is easy to apply the coloring material layer, and an even transfer image can be obtained.

[Brief explanation of drawings]

FIG. 1 is a graph showing the results of Examples and Comparative Examples, where the vertical axis shows the optical reflection density and the horizontal axis shows the number of printings.

Claims (1)

[Claims] 1. In a thermal transfer recording medium having a heat-melting coloring material layer on a support via an adhesive layer, the adhesive layer includes:
At least one polymeric compound selected from ethylene-ethyl acrylate, ethylene-vinyl acetate, vinyl chloride-vinyl acetate, and polyurethane resin, and behenic acid, ester wax, and α-olefin-maleic anhydride copolymer A thermal transfer recording medium comprising at least one compound selected from the following.