JPH0757560B2 - Transfer foil - Google Patents

Description

TECHNICAL FIELD The present invention relates to a transfer foil.

More specifically, it relates to a transfer foil capable of being heated and transferred to the surface of a plastic material dyed with a so-called sublimation dye to prevent discoloration or bleeding of the dye.

(Prior Art) Methods for dyeing plastic materials with so-called sublimable fuels are well known.

For example, a dye is made into an ink together with a binder resin and printed on a temporary support, and when this printed matter is overlaid on a plastic material and heated, only the dye in the ink penetrates into the plastic material and is dyed (transfer). Dyeing method). At this time, the ink is not transferred and peeled off together with the temporary support.

Alternatively, an ink containing a dye is directly printed on a plastic material, and then heated to allow the dye to penetrate into the plastic and dye it (penetration printing method). The ink layer is left as it is or is removed by peeling, but in any case, the dye has penetrated into the plastic and the image remains.

Dyes are believed to be sublimable and are believed to change from the solid state directly to the gaseous state, with such gaseous dyes penetrating into the plastic material. For this reason, dyes are generally called sublimable dyes. However, it is not strictly confirmed that there is no liquid state between the solid state and the gas state. It is also not clear whether the penetration into the plastic material occurs in the gaseous state or in the liquid state. For this reason, the dye is sometimes called a vaporizable dye or a heat-melt transfer dye.

A heating plate, a heating roll, an infrared panel heater or the like is used as a heating means for permeating the dye into the plastic material. In recent years, due to the development of dyes with excellent thermal responsiveness and improvement of thermal heads, there is a method of forming images by allowing dyes on the transfer ribbon to penetrate into the plastic material by the heat generated by the thermal heads. It has been developed.
The plastic material is a plastic film or a PVC card such as an identification card.

However, the dye is generally a disperse dye or an oil-soluble dye. Such a dye has a small polarity, and therefore it easily changes into a gas by heating and penetrates into the plastic material, but on the other hand, its binding force with the plastic material is also small, and it is violated by a plasticizer or an organic chemical, or mechanically damaged by scratching. In addition, the dye is decomposed by light, especially ultraviolet rays, and discolors or fades.

In order to prevent such a problem, an image receiving layer containing a polyester resin as a main component is provided on the surface of the plastic material to fix the dye, or the dye is improved to improve the fastness.

However, neither of the methods can essentially prevent external chemical or mechanical damage, and cannot avoid light rays such as ultraviolet rays.

(Problems to be solved by the invention) Therefore, according to the present invention, by transferring to a plastic surface dyed with such a sublimable dye, it is possible to prevent chemical and mechanical damage of a dyed image, and to prevent discoloration due to light. An object is to provide a transfer foil that can be prevented.

(Means for Solving the Problem) In order to achieve this object, the invention according to claim (1)
Provided is a transfer foil comprising a heat-resistant base film, a release layer which is easily peeled from the base film, a sublimation dye diffusion preventing layer, and an adhesive layer containing an ultraviolet absorber, which are sequentially laminated.

The invention according to claim (2) provides the transfer foil, wherein the release layer is made of a friction-resistant agent and a thermoplastic resin, and the thermoplastic resin is polymethylmethacrylate or an epoxy resin. .

The invention according to claim (3) provides the transfer foil, wherein the diffusion preventing layer of the sublimable dye is nitrocellulose.

Furthermore, the invention according to claim (4) provides the above transfer foil, wherein the adhesive layer is composed of an ultraviolet absorber and a thermoplastic resin having a glass transition point of 50 ° C. or higher.

The transfer foil (1) according to the present invention comprises a base film (11), a peeling layer (12), a diffusion preventing layer (13) and an adhesive layer (14) as shown in FIG.

The base film (11) is required to have heat resistance so as not to be softened and deformed by the heat pressure at the time of transfer. Such a base film (11) is known, and for example, a biaxially stretched polyethylene terephthalate film having a thickness of 3 to 30 μm can be used.

Further, the peeling layer (12) must be easily peeled from the base film (11) during thermal transfer. Further, it is necessary to fulfill the function of the protective film after being transferred. The function of the protective film is to prevent external chemical and mechanical damage of the image by the dye. In order to satisfy both functions, a mixture of anti-friction agent and thermoplastic resin may be used.

The thermoplastic resin prevents the injection of plasticizers and chemicals and reduces scratches caused by scratches. As the thermoplastic resin, polymethylmethacrylate or epoxy resin can be used. Among the existing thermoplastic resins, methyl methacrylate and epoxy resin have excellent plasticizer resistance and are easily peeled off from the base film (11). By using these resins for the release layer (12),
When a soft vinyl chloride sheet or a plastic eraser is brought into contact with the transferred image, the migration of the plasticizer contained therein can be prevented.

Further, it is possible to prevent penetration of chemicals such as acids, alkalis, alcohols, and kerosene, and prevent the influence on the image.

Further, the anti-friction agent is added to improve abrasion resistance and scratch resistance. For example, Teflon powder, polyethylene powder, animal wax, plant wax, mineral wax, petroleum wax and other natural wax, synthetic hydrocarbon wax, fatty alcohol and acid wax, fatty acid exter and glycerite wax, hydrogen. Wax, synthetic ketone wax, amine and amide wax, chlorinated hydrocarbon wax,
Examples thereof include synthetic animal wax waxes, synthetic waxes such as alpha-olefin waxes, and metal salts of higher fatty acids such as zinc stearate.

The release layer (12) has a total amount of thermoplastic resin and anti-friction agent of 100
85 to 95 parts by weight of thermoplastic resin, 5 parts by weight of anti-friction agent
~ 15 parts by weight is sufficient. The coating amount may be 1 to 3 g / m ² .

In the release layer (12), in addition to the above components, a release improving agent may be mixed in order to improve breakage during transfer. For example, linear saturated polyester resin. However, it should be limited to 0 to 3 parts by weight based on 100 parts by weight of the total amount of the thermoplastic resin and the anti-friction agent.

It should be noted that it is desirable not to add other additives such as an ultraviolet absorber to the release layer (12). Addition reduces the chemical resistance, or facilitates the penetration of plasticizers.
This is because it causes deterioration of the mechanical strength of the release layer.

The sublimation dye diffusion prevention layer (13) is provided on the surface of plastic such as polyvinyl chloride to prevent the image dyed with the sublimation dye from spreading to the outside. In order to prevent the diffusion of the sublimable dye, a natural polymer such as cellulose or a hydrophilic polymer obtained by modifying this is applied,
Nitrocellulose is most suitable in consideration of adhesiveness with ordinary thermoplastic resin, heat resistance, and water resistance. If there is no diffusion prevention layer (13), the dye diffuses through the adhesive layer (14) to the peeling layer (12) when left for a long time, and is sandwiched between eraser and soft vinyl chloride containing a plasticizer. If it is left, it will be diffused and transferred to an eraser or soft vinyl chloride, which will cause fading of the image.

Further, the diffusion transfer layer (13) does not serve as the adhesive layer (14),
This is because nitrocellulose has heat resistance and therefore does not adhere to the substrate during thermal transfer.

The diffusion prevention layer (13) is a hydrophilic polymer simple substance such as nitrocellulose, and its application amount may be 0.5 to 1.5 g / m ² .

The adhesive layer (14) adheres to the surface of the plastic material and blocks ultraviolet rays to prevent browning of the image due to the dye. To prevent the penetration of the plasticizer, the diffusion preventing layer (1)
It is provided separately from 3) and is made of a plastic material from the diffusion prevention layer (13). For this reason it consists of a mixture of UV absorbers and thermoplastics.

The ultraviolet absorber prevents discoloration of the dye due to light. That is, it absorbs ultraviolet rays having a wavelength of 250 to 400 nm and re-radiates the energy as heat energy that is harmless to the dye, and the ultraviolet absorber itself does not deteriorate. For this reason, an ultraviolet absorber having a maximum absorption wavelength of 250 to 400 nm is used. For example, salicylic acid-based ultraviolet absorbers such as phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate, 2,4-dihydroxybenzophenone, 2-hydroxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy. Benzophenone-based compounds such as 4-dodecyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone and 2-hydroxy-4-methoxy-5-sulfobenzophenone UV absorber, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole,
2- (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-
3'-tert-butyl-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-dite
benzotriazole-based UV absorbers such as rt-butylphenyl) -5-chlorobenzotriazole and 2- (2'-hydroxy-3 ', 5'-ditert-amylphenyl) benzotriazole, 2-ethylhexyl-2-cyano It is a cyanoacrylate-based ultraviolet absorber such as -3,3'-diphenyl acrylate and ethyl-2-cyano-3,3'-diphenyl acrylate.

The thermoplastic resin used for the adhesive layer (14) may have a glass transition point (Tg) of 50 ° C. or higher. If a resin having a glass transition temperature of less than 50 ° C. is used, after the transfer, the resin causes migration of the dye and causes image bleeding. Further, those having a glass transition point of 110 ° C. or lower are preferable. When a resin having a glass transition point of more than 110 ° C. is used, a high temperature is required for transfer, which not only puts a load on the transfer machine, but also plastic material such as polyvinyl chloride card may be deformed by heat.

Examples of the thermoplastic resin used for the adhesive layer (14) include polyester such as linear saturated polyester, vinyl chloride resin such as polyvinyl chloride or vinyl chloride-vinyl acetate copolymer resin, polyacrylic acid, polyacrylic acid. -2
-Methoxyethyl, polymethyl acrylate, poly (2-naphthyl acrylate), isobornyl polyacrylate, polymethacrylomethyl, polyacrylonitrile, polymethylchloroacrylate, polymethylmethacrylate, polyethylmethacrylate, polymethacrylic acid-tert. -Acrylic resins such as butyl, polyisobutyl methacrylate, polyphenyl methacrylate, copolymer resins of methyl methacrylate and alkyl methacrylate (where the alkyl group has 2 to 6 carbon atoms), polystyrene, polydivinylbenzene, polyvinylbenzene , Styrene-butadiene copolymer resin, vinyl resins such as styrene and alkyl methacrylate (wherein the alkyl group has 1 to 6 carbon atoms).

The adhesive layer (14) may contain 50 to 90 parts by weight of a thermoplastic resin and 10 to 50 parts by weight of an ultraviolet absorber based on 100 parts by weight of the total solid content. The coating amount is preferably 1 to 3 g / m ² .

The transfer foil (1) is first prepared by coating the release layer composition with a suitable solvent, and then coating and drying the coating on the base film (11) by a coating method such as gravure coating, roll coating, or barcode coating. Then, each of the diffusion prevention layer and the adhesive composition may be made into a coating material and sequentially applied.
The method of coating and applying the diffusion preventing layer and the adhesive composition is the same as the method of coating and applying the release layer composition.

The transfer foil (1) thus obtained can be transferred by stacking it on a plastic material dyed with a sublimation dye, applying heat and then peeling and removing only the base film (11). The transfer can be performed by heating to a temperature equal to or higher than the softening point of the thermoplastic resin contained in the adhesive layer (14). Usually 150
~ 250 ° C. The time may be about 1 to 10 seconds.

An example of using an identification card as the plastic material is shown in FIG. (2) is the original card, and the facial photograph is partially dyed with a sublimable dye (2a). Such a dyeing method is described in JP-A No. 63-22693, or the specification of Japanese Patent Application No. 216576 in 1989 and the drawings.

It will be apparent that the present invention can be applied not only to cards but also to any plastic material dyed with a sublimation dye.

(Example 1) Composition of release layer paint Polymethylmethacrylate 10 parts by weight (Tg; 105 ° C) (Mitsubishi Rayon Co., Ltd. BR-80) Teflon powder 1 〃 Toluene / 2-butanone (1/1) 40 〃 Composition of diffusion preventive layer paint Nitrocellulose (Cell line FM200 manufactured by Daicel Chemical Industries Ltd.) 15 parts by weight Toluene / 2-butanone (1/2) 85〃 Composition of adhesive layer paint Vinyl chloride-vinyl acetate copolymer 10 parts by weight Part (Tg; 65 ° C) (Sekisui Chemical Co., Ltd. S-Lec A) 2- (2'-hydroxy-5'-methylphenyl) -benzotriazole 2.5 〃 toluene / 2-butanone (2/1) 40 〃 thickness A release layer (12) was formed on a 12 μm polyethylene terephthalate film by using a gravure coater to apply the release layer coating material to a dry weight of 2.5 g / m ² and drying. The above diffusion preventive layer coating material was applied onto the layer by a gravure coater so that the dry weight was 0.8 g / m ² , and dried to form a diffusion preventive layer (13). Further, the above adhesive layer coating material was applied onto the layer with a gravure coater so as to have a dry weight of 1.8 g / m ² and dried to form an adhesive layer (14) to produce a transfer foil.

Each color of yellow, magenta and cyan was transfer dyed on a polyvinyl chloride card with a sublimation transfer ribbon using a color thermal printer. The transfer foil was laminated on the dyed surface with a laminator (MS Pouch H-140 manufactured by Meiko Shokai Co., Ltd.) at 150 ° C. for 2 seconds to remove the base film. The sublimation transfer ribbon is a 6 μm thick polyester film coated with three colors of sublimable ink consisting of dye and polyvinyl butyral. The yellow dye is Kacet Yellow AG (Nippon Kayaku Co., Ltd., Magenta). Dye is Kayacet Red 026 day Nippon Kayaku Co., Ltd.
Manufactured by Mitsubishi Kasei Co., Ltd., and the cyan dye is HSB9.

(Example 2) Composition of release layer coating composition Epoxy resin (softening point 148 ° C) 10 parts by weight (Epicoat 1009 manufactured by Yuka Shell Co., Ltd.) Polyethylene powder 0.5 〃 Toluene / 2-butanone (1/2) 40 〃 Diffusion prevention Composition of layer coating Nitrocellulose 15 parts by weight (Cell line FM200 manufactured by Daicel Chemical Industries, Ltd.) Toluene / 2-butanone (1/2) 85〃 Composition of adhesive layer coating Linear saturated polyester resin 10 parts by weight (Tg; 65 (Unit-3) UE-3200 manufactured by Unitika Ltd. 2-Hydroxy-4-methoxybenzophenone 6 〃 Toluene / 2-butanone (1/1) 40 〃 Each of the above paints was applied on a polyethylene terephthalate film having a thickness of 16 µm. A transfer foil was manufactured by applying in the same manner as in.

The card and transfer are the same as in Example 1.

(Example 3) Tg: saturated polyester resin of Tg = 47 ° C. instead of the saturated polyester resin of 65 ° C. (Vylon 300 manufactured by Toyobo Co., Ltd.)
A transfer foil was produced in the same manner as in Example 25 except that was used.

The card and transfer are the same as in Example 1.

Example 4 A release layer was used in which 2 parts by weight of a linear saturated polyester resin (Vylon 300 manufactured by Toyobo Co., Ltd.) was added as a release improving agent to 100 parts by weight of the total amount of the thermoplastic resin and the anti-friction agent. A transfer foil was manufactured in the same manner as in Example 1 except for the above.

The card and transfer are the same as in Example 1.

Comparative Example 1 The dyed card itself was used as Comparative Example 1 without using the transfer foil.

(Comparative Example 2) A transfer foil was produced in the same manner as in Example 1 except that 2- (2'-hydroxy-5'-methylphenyl) benzotriazole which was an ultraviolet absorber was omitted.

The card and transfer are the same as in Example 1.

(Comparative Example 3) Composition of release layer paint 4 parts by weight of nitrocellulose (Cell line FM200 manufactured by Daicel Chemical Industries, Ltd.) Polymethylmethacrylate 6 〃 (Tg: 105 ° C) (BR-80 manufactured by Mitsubishi Rayon Co., Ltd.) Teflon powder 1 〃 Toluene / 2-butanone (1/1) 40 〃 Adhesive layer paint composition Vinyl chloride-vinyl acetate copolymer 10 parts by weight (Tg: 65 ℃) (Sekisaku Chemical Co., Ltd. S-REC A) 2- (2'-Hydroxy-5'-methylphenyl) -benzotriazole 2.5〃 Toluene / 2-butanone (2/1) 40〃 A 12 μm thick polyethylene terephthalate film was dried using a gravure coater. weight
A coating layer was formed by coating and drying so that the release layer was 3.0 g / m ² .
A transfer foil was manufactured by coating the adhesive layer coating composition on the layer with a gravure coater so that the dry weight was 1.8 g / m ² and drying to form an adhesive layer.

The card and transfer are the same as in Example 1.

Table 1 shows scratch resistance, abrasion resistance, solvent resistance, heat resistance, and light resistance of Examples 1 to 3 and Comparative Examples 1 and 2. Each data was tested by the following method.

Scratch resistance: Scratch the surface with a pencil of H to measure the strength. ○ those that are not scratched, × those that are scratched.

Abrasion resistance ... Rubbing the card surface 2000 times with a Gakushin type robustness tester (using metal as a friction material) and observing the change in the surface. The one that does not change is ○, and the one that changes is ×.

Plastic resistance: A soft polyvinyl chloride sheet is brought into contact with the surface of the card, a load of 200 g / cm ² is applied, and it is kept in an environment of 40 ° C and 90% RH for 24 hours 48 hours and 100 hours, respectively, and the color change of the image And observe brown and bleeding. ○ that does not change
Those with discolored brown or bleeding.

Solvent resistance: Freon, ethanol, and gasoline are soaked in a cotton swab, the surface of the card is rubbed, and the change is observed. The ones that did not change at all were ○, and the ones that changed even once were ×.

Heat resistance: Store in an environment of 50 ° C, 90% RH for 48 hours and observe the discoloration of the image. The one that does not change is ○, and the one that has faded is ×.

Light resistance ... After irradiating ultraviolet rays for 40 hours with a fade meter,
Measures the reduction rate of image reflection density.

(Effects) As described above, according to the present invention, various chemicals such as scratch resistance, abrasion resistance, solvent resistance, etc. can be transferred onto a plastic material dyed with a sublimation dye and transferred to a plasticizer resistance. Also, a transfer foil is obtained which prevents mechanical damage and also prevents browning due to light such as ultraviolet rays.

In addition to this, when a thermoplastic resin having a glass transition point of 50 ° C. or higher is used for the adhesive layer, it is possible to obtain the effect of not causing image change due to heat.

Therefore, it can be used as a protective film transfer foil for an image of a sublimable dye such as an information recording card such as a prepaid card or an identification card.

[Brief description of drawings]

FIG. 1 is a sectional view of a transfer foil, and FIG. 2 is a sectional view after transfer. (1) Transfer foil (11) Base film (12) Release layer (13) Diffusion prevention layer (14) Adhesion layer (1a) Transfer layer (2) Card body (2a) …… Face photo with partial sublimation dye

Claims (4)

[Claims] 1. A transfer foil comprising a heat-resistant base film, a release layer which is easily peeled from the base film, a sublimation dye diffusion preventing layer, and an adhesive layer containing an ultraviolet absorber, which are successively laminated. 2. The release layer comprises a friction-resistant agent and a thermoplastic resin, and the thermoplastic resin is polymethylmethacrylate.
Alternatively, the transfer foil according to claim 1, which is an epoxy resin. 3. The transfer foil according to claim 1, wherein the sublimation dye diffusion preventing layer is nitrocellulose. 4. The adhesive layer has an ultraviolet absorber and a glass transition point
The transfer foil according to any one of claims (1) to (3), which is made of a thermoplastic resin having a temperature of 50 ° C or higher.