JP2620266B2 - Thermal transfer media - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer medium used for a thermal transfer device such as a printer or a facsimile, and more specifically, to record a character image of metallic luster such as gold and silver with low smoothness. The present invention relates to a thermal transfer medium for rough paper which can be recorded on paper.

[Prior Art] Conventionally, as an adhesive for a thermal transfer medium, a wax-based dispersion-type adhesive and a solvent-type polymer adhesive have been used alone or in combination.

However, when the above-mentioned adhesives are used alone or in a mixed system in the heat-sensitive transfer medium having a high metallic gloss as in the present invention, the following disadvantages are recognized together with the advantages, and it is difficult to cope with a wide range of rough paper. .

When the wax-based dispersion-type adhesive alone is used, its thermal conductivity is too good, so that its melt viscosity is low, and chipping phenomena during printing (general phenomena generally called voids, reverse transfer, etc.) tend to occur, and Beck smoothness is 100 sec. It is difficult to print on rough paper of less than 50 sec.

When the solvent-soluble polymer adhesive alone is used, the thermal conductivity is poor and high-speed printing cannot be performed.

Poor print sharpness (sharpness) due to high molecular weight.

In the case of a mixed system, the above two drawbacks appear. That is, since the thermal conductivity is too good, the melt viscosity is low, and a chipping phenomenon at printing (generally a phenomenon called hollow, reverse transfer, etc.) is likely to occur, and a Beck smoothness of 100 sec. Or less, especially 50 sec. Or less. Is difficult to print on rough paper.

 Poor thermal conductivity makes high speed printing impossible.

Poor print sharpness (sharpness) due to high molecular weight.

[Object of the Invention] The present invention has been made in view of the above-mentioned conventional drawbacks, and has as its object to provide a heat-sensitive transfer medium capable of recording a transfer image or the like having extremely good metallic luster.

[Constitution of the Invention] Directly on a base film or via a release agent layer,
In a thermal transfer medium in which at least a protective resin coating layer, a metal deposition layer, and an adhesive layer are sequentially formed, the adhesive layer is formed by laminating a wax-based dispersed adhesive layer and a solvent-soluble polymer adhesive layer in this order. The present invention relates to a thermal transfer medium for rough paper.

That is, in the thermal transfer medium of the present invention, a composite layer in which a wax-based dispersion type adhesive layer and a solvent-soluble type polymer adhesive layer are laminated in this order instead of a single adhesive layer of a conventional thermal transfer medium is used. As a result, thermal conductivity is improved, and sharp printing is obtained. Furthermore, the chipping phenomenon during printing is less likely to occur, and the Bekk smoothness is 100 sec. Or less, especially 50 sec.
The present invention has completed a heat-sensitive transfer medium capable of recording a transfer image or the like having extremely good metallic luster that can be printed on rough paper.

That is, according to the present invention, at least the protective resin coating layer (3), the metal deposition layer (4), and the adhesive layer (5) are provided directly on the base film (1) or via the release agent layer (2). In the thermal transfer medium formed sequentially, the adhesive layer (5) was formed by laminating a wax-based dispersion type adhesive layer (51) and a solvent-soluble type polymer adhesive layer (52) in this order, resulting in extremely good metal. An object of the present invention is to provide a thermal transfer medium capable of recording a glossy transfer image or the like.

Base film in thermal transfer medium of the present invention (1)
Any one can be used as long as it has a sufficient self-holding property, for example, polyester, polyamide polyadimide, polyethylene, polypropylene, cellulose acetate, polycarbonate, polyvinyl chloride,
Resins such as fluororesin, or film-like or sheet-like materials such as cellophane paper and glassine paper, release paper or release film are used as appropriate. In particular, the base film (1) is a film-like material of the above-mentioned resins and has a thickness of 2.5
It is preferable to use one having a thickness of about 12 μm because a thermal transfer medium free of wrinkles and cracks can be continuously mass-produced. In addition, the invention (Japanese Patent Application No.
-260774), a thin film of an inorganic substance, for example, an oxide such as SiO, SiO ₂ , TiO ₂ , ZnO, Al ₂ O ₃ , TiN, etc., in the bubble opposite to the side on which the thermal transfer layer of the plastic film is provided. Nitride, carbide such as TiC, carbon, Al, Ni, Cr, Ti, Ni
A hot-stick resistant material provided with a thin film of about 6 to 100 nm of a metal such as a -Cr alloy is also preferably used.

When the base film (1) does not have good releasability from the protective resin coating layer (3), a paraffin wax, silicone, a fluororesin, a surfactant or the like is applied to form the release agent layer (2). It may be formed.

In the thermal transfer medium of the present invention, the metal deposited layer is easily damaged by friction due to low mechanical strength,
A protective resin coating is provided on the surface of the metal deposition layer. The thickness of the protective resin coating is not particularly limited, but is usually appropriately selected from the range of 0.5 to 2 μm.

As a resin for forming such a protective resin coating film,
For example, any of a thermoplastic resin, a thermosetting resin, an electron beam curable resin, and an ultraviolet curable resin may be used. For example, acrylic resin, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polycarbonate, nitrocellulose, cellulose acetate Tate, urethane-based resins, urea-based resins, melamine-based resins, urea-melamine-based resins, epoxy-based resins, alkyd-based resins, aminoalkyd-based resins, rosin-modified maleic acid resins, and the like, or a mixture thereof are preferably used.

The protective resin layer is formed by applying an organic solvent solution of the resin for forming the protective resin coating film, an aqueous solution, or the like by a normal coating method such as a roll coating method, a gravure coating method, a reverse coating method, and a spray coating method. And drying (in the case of a thermosetting resin, an electron beam curable resin, an ultraviolet curable resin, etc., curing).

The protective resin layer may be colored with a coloring material such as a dye or a pigment as long as it is transparent or translucent.

The metal-deposited layer (4) of the thermal transfer medium of the present invention is formed on the protective resin layer by a conventional method such as aluminum, copper, silver, or the like.
It is formed by depositing a metal such as gold or an alloy thereof, and aluminum is most preferable in terms of gloss and cost.

As the metal deposited layer, for example, zinc, aluminum, gallium, indium, tin, and the like may be formed by a known metal (including alloy, hereinafter the same) thin film forming method such as a known vacuum deposition method, a sputtering method, and an ion plating method.
Nickel, silver, gold, copper, silicon, chromium, titanium, platinum,
A single substance, a mixture, an alloy, or the like capable of being deposited such as palladium is deposited to a thickness of about 10 to 100 nm. When the thickness is about 10 nm or less, almost no metallic luster is recognized, and there is no value in providing a metal vapor-deposited layer. Even when the thickness is about 100 nm or more, the metallic luster does not change and is not economical. The metal deposition layer is not limited to one layer but may be a plurality of layers. In this case, the type of metal may be changed for each layer. Also, the thickness of the metal deposition layer located on the surface side is set to about 30 nm or less so that an interference thin film layer made of a transparent resin or a transparent inorganic metal compound is interposed between the metal deposition located on the inner side to generate an interference iris color. It may be.

Examples of the wax-based dispersed adhesive layer (51) of the thermal transfer medium of the present invention include spermaceti, beeswax, lanolin,
Natural waxes such as carbana wax, candelilla wax, montan wax, synthetic waxes such as paraffin wax, microclean wax, oxidized wax, ester wax, and low molecular weight polyethylene, as well as tackifier fillers, plasticizers, antioxidants, etc. A single material or a mixture thereof is used. The thickness of the wax-based dispersed adhesive layer (51) is appropriately selected and determined according to the surface condition of the paper to be transferred, but is usually selected from a range of about 1 to 10 μm. Is relatively thin, about 1-2 μm.

Examples of the solvent-soluble polymer adhesive layer (52) of the thermal transfer medium of the present invention include higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, phlomenic acid and behenic acid, stearyl alcohol and behenyl alcohol. Esters such as higher alcohols, fatty acid esters of sucrose, fatty acid esters of sorbitan, amides such as stearinamide and oleinamide, polyamide resins, polyester resins, epoxy resins,
Polyurethane resin, acrylic resin, vinyl chloride resin, cellulose resin, polyvinyl resin, petroleum resin, ethylene-vinyl acetate copolymer resin, phenol resin, styrene resin, natural rubber, styrene butadiene rubber, Elastomers such as isoprene rubber and chloroprene rubber, rosin and derivatives thereof, terpene resins, hydrogenated petroleum resins, and the like, alone or mixed with a tackifier filler, a plasticizer, an antioxidant, and the like are used.
The thickness of the solvent-soluble polymer adhesive layer (52) is appropriately selected and determined according to the surface condition of the paper to be transferred, but is usually selected from the range of about 1 to 10 μm. Is relatively thin, about 1 to 2 μm when the surface is relatively smooth.

 Next, the present invention will be described with reference to examples.

[Example] Example 1 A mixed solvent composed of 20 parts of an acrylic resin (parts by weight, the same applies hereinafter) and 10 parts of chlorinated rubber, 30 parts of toluene, 20 parts of methyl isobutyl ketone, and 20 parts of cyclohexanone on a 3.5-μm-thick polyester film. Is applied and dried to form a protective resin layer having a thickness of 2 μm, aluminum is deposited thereon by vacuum evaporation to a thickness of 40 nm, and 20 parts of carnauba wax is further placed thereon. A coating solution formed by dissolving in 80 parts of toluene is applied and dried to form a wax-type dispersed adhesive layer having a thickness of 2 μm. Then, 10 parts of styrene-butadiene rubber, 7 parts of chlorinated polypropylene, and xylene resin are further formed thereon. 15 parts 50 parts toluene,
A coating solution dissolved in 50 parts of ethyl acetate was applied and dried to form a solvent-soluble polymer adhesive layer having a thickness of 2 μm to obtain a thermal transfer medium of the present invention.

Example 2 A coating solution obtained by dissolving 9 parts of paraffin wax and 1 part of ketone resin in a mixed solvent consisting of 70 parts of toluene, 10 parts of turpentine oil and 10 parts of petroleum naphtha was coated on a 6 μm thick polyester film, and dried. 1 μm
A coating solution formed by dissolving 25 parts of a styrene maleic acid resin and 55 parts of an oily dye in a mixed solvent consisting of 30 parts of toluene, 20 parts of methyl isobutyl ketone and 20 parts of cyclohexanone Is applied and dried to form a protective resin layer with a thickness of 2 μm, on which aluminum is vapor-deposited to a thickness of 40 nm by vacuum vapor deposition, and then 20 parts of carnauba wax is dissolved in 80 parts of toluene. The solution was applied and dried to form a wax-based dispersed adhesive layer having a thickness of 2 μm, followed by 10 parts of styrene-butadiene rubber, 7 parts of chlorinated polypropylene,
A coating solution comprising 15 parts of xylene resin dissolved in 50 parts of toluene and 50 parts of ethyl acetate is applied and dried to a thickness of 2 μm.
To form a heat-sensitive transfer medium of the present invention.

Comparative Example 1 Acrylic resin on 35 μm thick polyester film
A coating solution obtained by dissolving 20 parts and 10 parts of chlorinated rubber in a mixed solvent consisting of 30 parts of toluene, 20 parts of methyl isobutyl ketone and 20 parts of cyclohexanone is applied and dried to form a protective resin layer having a thickness of 2 μm. Then, aluminum is deposited to a thickness of 40 nm by a vacuum deposition method, and a coating solution obtained by dissolving 20 parts of beeswax in 80 parts of toluene is applied thereon and dried to form an adhesive layer having a thickness of 2 μm. A thermal transfer medium was obtained.

Comparative Example 2 A coating solution obtained by dissolving 9 parts of paraffin wax and 1 part of ketone resin in a mixed solvent consisting of 70 parts of toluene, 10 parts of turpentine oil and 10 parts of petroleum naphtha was applied onto a 6 μm thick polyester film, followed by drying. 1μm thick
And a coating solution obtained by dissolving 25 parts of a styrene maleic acid resin and 5 parts of an oil dye in a mixed solvent consisting of 30 parts of toluene, 20 parts of methyl isobutyl ketone and 20 parts of cyclohexanone. Is applied and dried to form a protective resin layer having a thickness of 2 μm, and aluminum is deposited thereon to a thickness of 40 nm by a vacuum deposition method. Further, styrene-butadiene rubber 10 parts, chlorinated polypropylene 7 parts, xylene 15 parts of resin 50 parts of toluene, 50 parts of ethyl acetate coating solution consisting of dissolved and dried,
An adhesive layer having a thickness of 2 μm was formed to obtain a thermal transfer medium.

Comparative Example 3 A coating solution obtained by dissolving 20 parts of an acrylic resin and 10 parts of a chlorinated rubber in a mixed solvent consisting of 30 parts of toluene, 20 parts of methyl isobutyl ketone and 20 parts of cyclohexanone was applied to a 3.5 μm thick polyester film and dried. A protective resin layer having a thickness of 2 μm is formed thereon, and aluminum is vapor-deposited thereon to a thickness of 40 nm by a vacuum vapor deposition method. Further, 10 parts of a polyamide resin and 10 parts of carnauba wax are further coated with 70 parts of toluene, 70 parts of isopropyl alcohol and A coating solution dissolved in a mixed solvent consisting of 2 parts by weight was applied and dried to form an adhesive layer having a thickness of 2 μm to obtain a thermal transfer medium.

Comparative Example 4 A coating solution obtained by dissolving 9 parts of paraffin wax and 1 part of ketone resin in a mixed solvent consisting of 70 parts of toluene, 10 parts of turpentine oil and 10 parts of petroleum naphtha was applied to a 9 μm-thick polyester film and dried. 1 μm
Is formed by dissolving 25 parts of a styrene-maleic acid resin and 5 parts of an oily dye in a mixed solvent consisting of 30 parts of toluene, 20 parts of methyl isobutyl ketone and 20 parts of cyclohexanone. The solution was applied and dried to form a protective resin layer having a thickness of 2 μm, on which aluminum was vapor-deposited to a thickness of 40 nm by vacuum vapor deposition, and then 20 parts of paraffin wax and an ethylene-vinyl acetate copolymer resin A coating solution prepared by dissolving 10 parts in a mixed solvent consisting of 50 parts of toluene and 20 parts of turpentine oil was applied and dried to form an adhesive layer having a thickness of 3 μm to obtain a thermal transfer medium.

[Effects of the Invention] Using the thermal transfer media obtained in Examples 1 and 2 and Comparative Examples 1, 2, 3, and 4, printing was performed on plain paper with a personal word processor Canon PW-70 (manufactured by Canon Inc.).

Character images printed on rough paper of 50 sec. Or less using the thermal transfer medium of the present invention obtained in Examples 1 and 2 exhibited extremely beautiful metallic luster.

50 seconds using the thermal transfer medium obtained in Comparative Examples 1-4.
In the following character images printed on rough paper, those in Comparative Example 1 had too low thermal viscosity due to too good thermal conductivity, and chipping phenomena during printing (generally referred to as hollowing, reverse transfer, etc.) Phenomenon was observed. In the case of Comparative Example 2, not only the thermal conductivity was poor and it was not possible to cope with high-speed printing, but also the sharpness of the printing due to the large molecular weight.
The prints were poor and the prints were unclear. In the case of Comparative Examples 3 and 4, the thermal conductivity was still too low, the melt viscosity was low, and the chipping phenomenon at the time of printing (generally referred to as hollow, reverse transfer, etc.) Phenomenon) was observed, and in addition, those having a large molecular weight were mixed, so that the sharpness of the print was poor and the print was unclear.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the basic structure of the thermal transfer medium of the present invention. (Signs in the drawings) (1): Base film (2): Release agent layer (3): Protective resin coating layer (4): Metal deposition layer (5): Adhesive layer (51): Wax dispersion type Adhesive layer (52): Solvent-soluble polymer adhesive layer

Claims (1)

(57) [Claims] 1. A heat-sensitive transfer medium in which at least a protective resin coating layer, a metal deposition layer, and an adhesive layer are sequentially formed on a base film directly or via a release agent layer, the adhesive layer has a wax-based dispersion. A rough paper-compatible thermal transfer medium, comprising a lamination type adhesive layer and a solvent-soluble polymer adhesive layer laminated in this order.