JPH10297122A - Intermediate transfer sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an image whose reproducibility in dots is superbly satisfactory and facilitate the retransfer with an outstanding adhesion the an arbitrarily selected image display base material by providing a soft resin layer mainly composed of a resin of specific modulus between a peelable protecting layer and an adhesive layer combined with an image receiving function. SOLUTION: This intermediate transfer sheet 10A comprises a peelable protecting layer 2 and an adhesive layer 3 combined with an image receiving function laminated sequentially on a support 1 and a soft resin layer 4 formed between the peelable protecting layer 2 and the adhesive layer 3 combined with an image receiving function. The soft resin layer 4 is formed of a soft resin as a principal component showing 80 kg/cm<2> at 100% modulus. When the 100% modulus exceeds 80 kg/cm<2> , the effect to enhance the adhesion between the soft resin layer 4 and a transfer ribbon on account of a deformation of the layer 4 is diminished. When an image is transferred from the transfer ribbon, the unevenness of the surfaces of a head, the transfer ribbon and the intermediate transfer sheet is absorbed by the deformation of the soft resin layer 4, so that an image is positively transferred in such a manner that dots are reproduced clearly. Even when the image is retransferred to an image display base, the soft resin layer 4 is deformed, which in turn, enables the satisfactory retransfer of the image even to the uneven surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an intermediate transfer sheet on which an image is formed by thermal transfer recording and the formed image is re-transferred to an image display substrate to which an image is ultimately applied.

[0002]

2. Description of the Related Art Hitherto, as a method of forming an image pattern by a thermal transfer recording means based on image data, a sublimation transfer method and a thermal fusion transfer method have been known.

The image formation by the sublimation transfer method or the hot-melt transfer method is more specifically performed, for example, as follows.

First, as shown in FIG. 5, a thermal transfer layer 22 containing a dye or pigment such as yellow (Y), magenta (M), cyan (C), etc. Is prepared, a recording medium 30 (for example, photographic paper, plain paper, an OHP sheet, etc.) to which an image is to be applied, and the above-described transfer ribbon 20 are attached to the printer 40. The ink is passed between the platen roller 41 and the thermal head 42, and the heating element group of the thermal head 42 is appropriately heated based on the image data, so that an image pattern based on the image data is sublimated on the thermal transfer layer 22 of the transfer ribbon 20. It is formed on the recording medium 30 by transfer or thermal fusion transfer. In this case, for example, the transfer ribbon 20 is conveyed in the direction of arrow B, and the recording medium 30 is conveyed in the direction of arrow A or A '. Finally, the transfer of each color of Y, M, and C is performed. As a result, as shown in FIG. 6, for example, a card can be used as the recording medium 30 and a color image 31 such as a face photograph can be formed thereon.

On the other hand, depending on the material and shape of a substrate to which an image is to be provided (hereinafter, referred to as an image display substrate),
It may be difficult to apply the image forming method of thermal transfer recording as described above from the technical, cost, or mass productivity point of view. Therefore, in such a case, an image is formed on the intermediate transfer sheet for the time being, and then the image formed on the intermediate transfer sheet is re-transferred to an image display base material as a final product by a heat roller or a hot press transfer. A method has been proposed (JP-A-63-81093).

FIG. 4 is a layer configuration diagram of the intermediate transfer sheet 10. As shown in the drawing, the intermediate transfer sheet 10 has a support 1 on which a peelable protective layer 2 and an image receiving / adhesive layer 3 are sequentially laminated. Here, the image receiving / adhesive layer 3 is a layer on which an image is formed by thermal transfer recording and has thermal adhesion to an image display substrate, and the peelable protective layer 2 is a layer on which an image is formed. When the image-receiving / adhesive layer 3 is thermally bonded to the image display substrate, the image-receiving / adhesive layer 3 is peeled off from the support and adhered together with the image-receiving / adhesive layer 3 onto the image display substrate. It is a layer that protects the image.

Image formation using such an intermediate transfer sheet is used, for example, when forming a thermal transfer image on an ID card such as a credit card or a members card, a passport, or the like.

On the other hand, a special surface layer is provided on the surface of an image display substrate containing personal identification data such as an ID card such as a credit card or a members card or personal identification data such as a passport in order to prevent tampering or forgery. That has been done. For example, it has been proposed to attach a sheet called a transparent hologram (see Japanese Patent Application Laid-Open No. 61-254975) on an image display base material, to recognize a hologram image together with an image pattern, thereby preventing tampering. ing. Therefore, when an image is formed on the cards or the like using the above-described intermediate transfer sheet, it is necessary to transfer the image receiving / adhesive layer to a special surface layer to prevent tampering or forgery. Has become.

[0009]

By the way, in the image forming method using the intermediate transfer sheet, the transfer from the transfer ribbon to the intermediate transfer sheet and the transfer from the intermediate transfer sheet to the final image display substrate are two. In order to transfer images in stages, in order to obtain a good image on the final image display substrate, it is necessary to reliably transfer the image to the intermediate transfer sheet with high dot reproducibility. In order to transfer such an image,
When forming an image on the intermediate transfer sheet, it is necessary to make the adhesion between the transfer ribbon and the intermediate transfer sheet perfect so that air gaps and voids due to fine dust are not formed therebetween. In particular, when an image is formed by hot-melt transfer, complete adhesion is required as compared to when an image is formed by sublimation transfer.

As a method of improving the adhesion between the transfer ribbon and the intermediate transfer sheet, there is a method of using a non-soft urethane resin or the like for the image receiving / adhesive layer. However, such a resin is liable to cause blocking and has a problem that an unprinted portion is transferred due to an excessively high initial adhesiveness and that a gradation of an image is hardly produced.

The support of the intermediate transfer sheet is made of paper or foamed PE.
There is also a method of improving the adhesion between the transfer ribbon and the intermediate transfer sheet by forming the material from a porous material having a cushioning property such as T. However, when the adhesion is improved by this method, the cushioning effect is reduced because the distance between the cushioning support portion and the image receiving / adhesive layer portion for forming an image is too large, and the fine dust is reduced. However, there is a problem that the air gap cannot be eliminated due to the air gap.

Further, when retransferring from the intermediate transfer sheet to the final image display base material, if the surface of the image display base material has irregularities, for example, in the case of cards, etc., falsification or forgery prevention is prevented. Therefore, if a hologram-forming layer is formed on the surface, in order to perform good transfer, the image receiving / adhesive layer of the intermediate transfer sheet must be made unnecessarily thick or the retransfer conditions must be high temperature and high pressure. There is a problem that it does not.

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems of the prior art. The present invention relates to an intermediate transfer sheet in which a peelable protective layer and an image-receiving / adhesive layer are sequentially laminated on a support. Sometimes it shows excellent adhesion to the transfer ribbon, thereby enabling good image formation with high dot reproducibility, and excellent image receiving and adhesive layer for any image display substrate To have an adhesive property, so that re-transfer is easily performed, and further, by using an intermediate transfer sheet, an image display substrate having a falsification or forgery prevention ability can be easily obtained. The purpose is to do.

[0014]

In order to achieve the above-mentioned object, the present invention provides a method according to the present invention, wherein at least a peelable protective layer and an image-receiving / adhesive layer are sequentially laminated on a support. An image is formed by thermal transfer recording, and has thermal adhesiveness to the image display substrate, and the releasable protective layer is peeled off from the support during thermal adhesion of the image receiving / adhesive layer to the image display substrate. An intermediate transfer sheet to be attached to an image display substrate, wherein an intermediate transfer sheet having a soft resin layer whose main component is a resin having a 100% modulus of 80 kg / cm ² or less is provided between a peelable protective layer and an image receiving / adhesive layer. A sheet is provided (claim 1).

[0015] Such an intermediate transfer sheet, which can easily impart a falsification or forgery preventing ability to an image display substrate, is provided between a peelable protective layer and a soft resin layer, or between a soft resin layer and a soft resin layer. An embodiment is provided in which an anti-counterfeiting layer is formed between the layer and the image-receiving / adhesive layer to increase the forgery difficulty (claims 4 and 5).

According to the intermediate transfer sheet of the present invention, the 100% modulus between the releasable protective layer and the image-receiving / adhesive layer is 80%.
Because of having a soft resin layer containing a resin of kg / cm ² or less as a main component, when transferring an image from the transfer ribbon to the intermediate transfer sheet, the unevenness of the head, the fine unevenness of the transfer ribbon surface, and the fineness of the intermediate transfer sheet surface The soft resin layer is deformed according to the irregularities. Also, unevenness due to fine dust and the like is similarly deformed and absorbed by the soft resin layer. For this reason, it is difficult to form an air gap between the transfer ribbon and the intermediate transfer sheet, the image pattern based on the image data can be reliably transferred to the intermediate transfer sheet, and the print quality is improved.

Also, when retransferring from the intermediate transfer sheet to the final image display substrate, the soft resin layer is deformed. Is possible.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. In each of the drawings, the same reference numerals represent the same or equivalent components.

FIG. 1 is a layer configuration diagram of a basic embodiment of the intermediate transfer sheet of the present invention. This intermediate transfer sheet 10A
Is provided on a support 1 on a peelable protective layer 2 and an image receiving / adhesive layer 3.
Are sequentially laminated, and a soft resin layer 4 is formed between the releasable protective layer 2 and the image receiving / adhesive layer 3.

Here, the support 1 is formed from a heat-resistant film which is not softened and deformed by heat or pressure during transfer from the transfer ribbon to the intermediate transfer sheet and during transfer from the intermediate transfer sheet to the image display substrate. . As such a film, a film used as a support in a known transfer ribbon or an intermediate transfer sheet can be used. For example, a biaxially stretched polyethylene terephthalate film having a thickness of 3 to 50 μm can be preferably used.

The peelable protective layer 2 is easily peeled off from the support 1 when the image receiving / adhesive layer 3 is thermally bonded to the image display substrate, and is adhered to the image display substrate. This layer functions as a protective film for an image on the display substrate.

Here, the function of the protective film refers to a function of preventing external chemical and mechanical damage of the image. In order to satisfy both functions, it is preferable that the peelable protective layer 2 is formed from a mixture of a thermoplastic resin and an anti-friction agent. That is, by forming the peelable protective layer 2 from a thermoplastic resin, even when a soft vinyl chloride sheet or a plastic eraser or the like is brought into contact with the image finally transferred to the image display substrate, it is included in these. Transfer of the plasticizer to the image can be prevented. Further, it is possible to prevent chemicals such as acids, alkalis, alcohols, and kerosene from penetrating, thereby preventing the influence on images. As the thermoplastic resin, polymethyl methacrylate, epoxy resin, or the like is preferable because it has excellent plasticizer resistance, can reduce scratches due to scratching, and can be easily separated from the support 1.

The anti-friction agent used for forming the peelable protective layer 2 is added for improving abrasion resistance and scratch resistance. Examples of such anti-friction agents include higher aliphatic metal salts such as Teflon powder (polytetrafluoroethylene), polyethylene powder, natural wax, synthetic wax, and zinc stearate.

The releasable protective layer 2 may contain various additives in addition to the thermoplastic resin and the anti-friction agent. For example, a release improver can be blended to facilitate release from the support 1 during retransfer. Examples of the release improver include a linear saturated polyester resin.

The mixing ratio of the components constituting the peelable protective layer 2 is preferably from 75 to 95 parts of the thermoplastic resin and from 5 to 25 parts of the anti-friction agent in relation to the above-mentioned thermoplastic resin and anti-friction agent. .

The coating amount of the peelable protective layer 2 is 0.5 to 4 g.
/ M ² . If the coating amount is too small, the effect as a protective film such as abrasion resistance becomes insufficient,
If the amount is too large, there is no effect corresponding thereto, and the texture of the image after being transferred to the image display substrate is inferior.

The image receiving / adhesive layer 3 forms an image from a transfer ribbon by thermal transfer recording, and finally heat adheres to an image display substrate to form an image on the image display substrate.

The image receiving / adhesive layer 3 can be formed of a thermoplastic resin, and particularly has a glass transition point (Tg) of 50.
It is preferred to be formed from a thermoplastic resin having a temperature of 110 ° C. or higher and 110 ° C. or lower. When the glass transition point is lower than 50 ° C., when the intermediate transfer sheet is not used before the transfer from the transfer ribbon to the intermediate transfer sheet, and the intermediate transfer sheet is stored in a wound state, blocking may occur. After the transfer, the image may be blurred.
On the other hand, if the glass transition point (Tg) exceeds 110 ° C., a high temperature is required to transfer an image from the transfer ribbon to the intermediate transfer sheet, and a large load is applied to the thermal head used for this transfer, A high temperature is also required at the time of retransfer to the image display substrate, which may damage the image display substrate.

The thermoplastic resin preferable for forming the image receiving / adhesive layer 3 is appropriately selected according to the type of thermal transfer recording system (sublimation transfer system, hot melt transfer system, wax type melt transfer system, etc.) applied to the intermediate transfer sheet. You can choose,
Examples of resins that can be generally used for various types of thermal transfer recording methods include polyester resins such as linear saturated polyester, polyvinyl chloride resins such as polyvinyl chloride and vinyl chloride / vinyl acetate copolymer, and polyacrylic acid. Acrylic resins such as polymethyl acrylate, poly (naphthyl-2-naphthyl), polymethacrylic acid, polyethyl methacrylate, polyacrylonitrile, and polymethacrylomethyl;
Examples include vinyl resins such as polystyrene, polyvinylbenzene, polyvinylbutyral, and styrene-butadiene copolymer.

Various fillers can be added to the image receiving / adhesive layer 3 for the purpose of preventing blocking. Examples of such a filler include Teflon (polytetrafluoroethylene) -based fine particles, silicone resin fine particles, benzoguanamine resin-melamine resin condensate fine particles, starch, calcium carbonate, titanium oxide, talc, kaolin, zinc oxide, calcium carbonate, Silica and the like can be mentioned. The addition amount of these fillers is preferably 1 to 20 parts by weight based on 100 parts of the thermoplastic resin forming the image receiving / adhesive layer 3.

In addition to the image receiving / adhesive layer 3, various additives such as an ultraviolet absorber, a film forming aid, a coating solution stabilizer, and a leveling agent can be added as required.

The coating amount of the image receiving / adhesive layer 3 is 0.5
g / m ² or more. If the amount is too small, once an image is formed, the adhesive force to the image display substrate when the image is re-transferred to the image display substrate becomes insufficient. Can not.

The soft resin layer 4 is a layer characteristic of the present invention, and is provided between the above-mentioned releasable protective layer 2 and the image receiving / adhesive layer 3.
It is formed mainly of a soft resin having a 100% modulus of 80 kg / cm ² or less. 100% modulus is 80kg
/ Cm ² , the effect of improving the adhesion between the intermediate transfer sheet and the transfer ribbon due to deformation of the soft resin layer 4 is small, and the effect of the present invention cannot be obtained.

The kind of the soft resin is not particularly limited as long as the 100% modulus is 80 kg / cm ² or less. For example, ethylene / vinyl acetate copolymer resin, epoxy resin, polyurethane resin, rosin Modified phenol resins, polyolefin resins, polyamide resins, and the like can be given, and among them, polyurethane resins are preferable from the viewpoint of adhesiveness. Further, a laminate composed of two or more of these resin layers may be used.

In the present invention, the use of these soft resins as a main component means that the 100% modulus of the entire resin constituting the soft resin layer is 80 kg / cm.
^As long as it is ² or less, it means that the individual component resins of the soft resin layer may contain a resin having a 100% modulus of more than 80 kg / cm ² .

Various additives can be added to the soft resin layer 4 for the purpose of improving the blocking property. For example, inorganic fillers such as silica, talc and calcium carbonate, organic fillers such as polyethylene powder, stearic acid amide and starch, various waxes and the like can be mentioned. However, when a large amount of these additives is added, the soft resin layer 4 becomes hard and the effect of improving the adhesion between the transfer ribbon and the image receiving / adhesive layer 3 is impaired. It is preferable to use 20% by weight of inorganic fillers.
It is preferable to set the following.

When the thickness of the soft resin layer 4 is less than 1 μm, there is almost no effect of improving the adhesion due to deformation of the soft resin layer 4, and when it exceeds 30 μm, the intermediate transfer sheet becomes unnecessarily thick. When the final image is retransferred to the image display substrate, the layer is hard to be cut, so that burrs and the like are easily generated. Therefore, the thickness of the soft resin layer 4 is practically preferably 1 to 30 μm, and particularly preferably 2 to 10 μm.

FIG. 1 shows that the above-mentioned releasable protective layer 2, soft resin layer 4 and image-receiving / adhesive layer 3 are sequentially laminated on a support 1.
As a method of manufacturing the intermediate transfer sheet 10A, the components forming each layer are dissolved in an appropriate solvent to form a coating liquid,
Gravure coating, roll coating coating,
The steps of coating and drying according to a known coating method such as bar coating may be repeated.

The intermediate transfer sheet according to the present invention is provided with the above-mentioned laminated structure in which a peelable protective layer 2, a soft resin layer 4 and an image receiving / adhesive layer 3 are sequentially laminated on a support 1, if necessary. Layers can be provided. For example, like the intermediate transfer sheet 10 </ b> B shown in FIG. 2, a forgery prevention layer 5 that increases the difficulty of forgery can be formed between the peelable protective layer 2 and the soft resin layer 4. The forgery prevention layer 5 may be formed between the soft resin layer 4 and the image receiving / adhesive layer 3 as in the intermediate transfer sheet 10C shown in FIG.

By forming the anti-counterfeit layer 5 in this manner, the anti-counterfeit layer 5 can be adhered to the image display substrate when the image is re-transferred to the image display substrate. In order to prevent tampering and forgery, it is not necessary to provide a special surface layer such as a hologram forming layer on the image display substrate in advance.

More specifically, the anti-counterfeit layer 5
For example, a transparent hologram layer formed of a hologram forming layer having an uneven pattern and a transparent thin film layer formed of a transparent material having a higher refractive index than the hologram forming layer and provided along the uneven surface of the hologram forming layer is formed. can do.

Here, as a method of forming the hologram-forming layer, for example, a nickel press plate on which a fine concavo-convex pattern constituting a relief hologram is formed is placed on a transparent resin layer (refractive layer) for forming the hologram-forming layer. Rate n =
1.3 to 1.6) may be heated and pressed to form a hologram pattern. The hologram-forming layer may have a hologram pattern on the surface of the hologram-forming layer or in the layer. For example, the hologram-forming layer forms fine irregularities by a two-beam interference or a diffraction grating (grating) by an electron beam (EB). A grating hologram, a Lippmann hologram, or the like may be provided.

The transparent resin forming the hologram pattern has good embossing properties, hardly generates press unevenness, provides a bright reproduced image, and has a peelable protective layer 2.
And a resin having good adhesiveness to the permeable thin film layer, for example, polyvinyl chloride resin, vinyl chloride-vinyl acetate copolymer, polycarbonate resin, thermoplastic resin such as polystyrene resin, unsaturated polyester resin, melamine resin , Epoxy resins, thermosetting resins such as urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, polyol (meth) acrylate, melamine (meth) acrylate, triazine (meth) acrylate or mixtures thereof, Further, a thermoformable material having a radical polymerizable unsaturated group or the like can be used. In addition, any material having stability capable of forming a hologram image can be used.

On the other hand, the transparent thin film layer is formed of a transparent material having a higher refractive index than the hologram forming layer (refractive index n = 1.3 to 1.6) as described above. For example, inorganic materials shown in the following Table 1 can be used. In addition, the transparent thin film layer may be formed by stacking a plurality of layers, may be combined with layers having different refractive indices, and is a multilayer in which layers having a high refractive index and layers having a low refractive index are alternately laminated. It may be a film.

As a method for forming the permeable thin film layer, film forming means such as a vacuum evaporation method, a sputtering method, and an ion plating method can be used.
It is preferable to set the range of 0 nm to 1000 nm.

[0046]

[Table 1]

In addition, the anti-counterfeit layer 5 includes a layer containing a fluorescent substance, a layer containing a compound absorbing a specific infrared ray,
A layer containing a magnetic material, a fine print layer, and the like can also be provided.

Each layer constituting these anti-counterfeit layers 5
A plurality may be provided simultaneously. Further, as the forgery prevention layer 5, it is preferable to provide a transparent hologram layer layer among the various forgery prevention layers 5 described above.

In the intermediate transfer sheet of the present invention, the adhesive intermediate layer and the diffusion of the dye may be provided between the peelable protective layer 2, the forgery prevention layer 5, the soft resin layer 4, and the image receiving / adhesive layer 3, if necessary. Layers such as a prevention layer and an ultraviolet absorbing layer may be provided.
Further, a back coat containing a lubricant, an antistatic agent and the like may be provided on the back surface of the support 1 (the surface opposite to the image receiving / adhesive layer 3).

The image formation on the intermediate transfer sheet of the present invention is performed as follows.
The image forming method can be performed by an image forming method of any method belonging to the thermal transfer recording method, such as a sublimation transfer method, a thermal melt transfer method, and a wax-type melt transfer method. Further, retransfer of an image from the intermediate transfer sheet to the image display substrate can be performed by a method using a hot plate, a hot roll, or the like.

[0051]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments.

Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3 (1) Production of Intermediate Transfer Sheet An intermediate transfer sheet having the layer structure shown in FIG. 1 and suitable for sublimation transfer recording A transfer sheet was prepared as follows by changing the soft resin layer and the constituent resin. Similarly, an intermediate transfer sheet of a comparative example was prepared.

A support 1 was prepared on a polyethylene terephthalate film having a thickness of 16 μm, on which a composition for forming a peelable protective layer having a composition shown in Table 2 and a soft resin having a composition shown in Table 3 or Table 4 were provided. The composition for forming a layer and the composition for forming an image receiving / adhesive layer having the composition shown in Table 5 were sequentially applied and dried (drying conditions: 100 ° C., 5 min). At that time, the coating amount at the time of drying was 1.5 kg / m ² , 5 kg / m ² , and 2 k, respectively.
g / m ² .

[0054]

[Table 2]

[0055]

[Table 3]

[0056]

[Table 4]

[0057]

[Table 5]

(2) Production of Sublimation Transfer Ribbon A transfer ribbon for sublimation transfer recording on the intermediate transfer sheet produced in the above (1) was produced as follows.

First, sublimable dyes of three colors (yellow,
Cyan, magenta) are dispersed in polyvinyl butyral, respectively, to prepare a dye ink, and a gravure coater is used to coat and dry the three colors on a 6 μm-thick polyester film so that the colors are alternately arranged. A transfer ribbon having a dye layer was produced.

(3) Characteristic evaluation The sublimation transfer ribbon obtained in the above (2) and the intermediate transfer sheet obtained in the above (1) are set in a printer, and the heating elements of the thermal head are heated based on image data. A 16 gradation test pattern was formed on the image receiving / adhesive layer of the intermediate transfer sheet.

Further, a polyvinyl chloride base material is prepared as a final image display base material, the image receiving / adhesive layer of the intermediate transfer sheet is brought into contact with the base material, and a heating medium is applied from the intermediate transfer sheet side. The image receiving / adhesive layer was adhered to the substrate by applying pressure and heating (heating temperature: 150 ° C.), and the releasable protective layer was peeled off the support of the intermediate transfer sheet, and the image was retransferred to the image display substrate.

In order to evaluate the dot reproducibility of the image on the final image display substrate manufactured as described above, the dot shape was observed with a microscope. When the observed dot shape is round and large, the shape and size are uniform, and when the transfer quality is good, the mark is ○, when the transfer quality is moderate, the dot is not round, and the dot shape is not round and irregular. In the case where the transfer quality was poor, the size was small, and the transfer quality was poor, the evaluation was evaluated as x. The results are shown in Table 6 or Table 7.

Also, 100% of the resin used for the soft resin layer
Modulus was measured. The results are shown in Table 6 or Table 7.

[0064]

[Table 6]

[0065]

[Table 7]

Example 2, Comparative Example 2 (1) Production of Intermediate Transfer Sheet of Example 2 Having Forgery Prevention Layer The intermediate transfer of Example 2 having the layer configuration shown in FIG. 2 and suitable for hot-melt transfer recording A sheet capable of adhering a forgery prevention layer to an image display substrate was produced as follows.

A 6 μm-thick polyethylene terephthalate film was prepared as a support 1, and the composition for forming a releasable protective layer shown in Table 2 was used thereon. A protective layer was formed. Next, in order to form a forgery prevention layer 5 comprising a hologram forming layer having a hologram forming surface and a transparent thin film layer thereon, first, a hologram forming layer composition having a composition shown in Table 8 was used. A hologram forming layer is provided (coating amount 0.8 kg /
m ² ), a nickel press plate on which a fine uneven pattern constituting a relief hologram was formed was heated and pressed (95 ° C.) to form a hologram-formed surface. Then, a ZnS film having a thickness of 50 nm was formed on the hologram formation surface as a transparent thin film layer by a vacuum evaporation method.

Thereafter, a soft resin layer 4 was formed using the same soft resin layer forming composition as in Example 1-2 (Table 3), and a composition for forming an image receiving / adhesive layer having the composition shown in Table 9 was obtained. The image receiving / adhesive layer 3 was formed in the same manner as in Example 1 to obtain an intermediate transfer sheet of Example 2.

[0069]

[Table 8]

[0070]

[Table 9]

(2) Preparation of Intermediate Transfer Sheet of Comparative Example 2 Having Forgery Prevention Layer In the same manner as in Example 2 except that the soft resin layer was not formed,
An intermediate transfer sheet of Comparative Example 2 having a forgery prevention layer was produced.

(3) Production of hot-melt transfer ribbon First, pigments of three colors (yellow, cyan, magenta)
Is dispersed in polyvinyl butyral to prepare an ink, and coated with a gravure coater on a 6 μm-thick polyester film so that the respective colors are arranged in a plane-sequential manner, and dried to obtain a transfer having a three-color ink layer. The ribbon was manufactured.

(4) Evaluation of Characteristics The intermediate transfer sheet of Example 2 and Comparative Example 2 obtained in the above (1) and (2) and the hot melt transfer ribbon obtained in the above (3) were set in a printer, and The heating element group of the head is caused to generate heat based on the image data, and the heat is applied to the image receiving / adhesive layer of the intermediate transfer sheet.
A 6-tone test pattern was formed.

Further, a 200 μm thick paper base material was prepared as a final image display base material, and the image receiving / adhesive layer of the intermediate transfer sheet was brought into contact with the base material. The image receiving / adhesive layer was pressed against the substrate by applying pressure (heating temperature: 150 ° C.), and the releasable protective layer was released from the support of the intermediate transfer sheet, and the image was retransferred to the image display substrate.

Cellophane tape was adhered to the surface of the image display substrate on which the image was retransferred as described above and peeled off. In Comparative Example 2 having no soft resin layer, the image display substrate made of paper was Although peeling occurred between the image-receiving substrate and the image display substrate in the case of Example 2 having the soft resin layer, the image-receiving substrate did not peel off.

Example 3 An intermediate transfer sheet was prepared in the same manner as in Example 1-2, except that the coating amount after drying the soft resin layer was 30 kg / m ² . Then, an image was transferred to the intermediate transfer sheet using a sublimation transfer ribbon, and the formed image was re-transferred to a polyvinyl chloride base material.

As a result, no burr was generated on the intermediate transfer sheet having the soft resin layer produced in Example 1 of 5 kg / m ² , whereas the soft resin layer prepared here was 30 kg / m ^2.
In the intermediate transfer sheet m ^2, outside the burrs of the final image display body it is slightly observed. Therefore, it is understood that the coating amount of the soft resin layer is preferably set to about 30 kg / m ² or less.

[0078]

According to the intermediate transfer sheet of the present invention, a soft resin layer made of a soft resin having a 100% modulus of 80 kg / cm ² or less is provided between the peelable protective layer and the image receiving / adhesive layer. Therefore, at the time of image transfer from the transfer ribbon to the intermediate transfer sheet, the soft resin layer is deformed in accordance with the unevenness of the head and the fine unevenness of the transfer ribbon and the intermediate transfer sheet. For this reason, it is difficult to form an air gap or the like between the transfer ribbon and the intermediate transfer sheet, and the soft resin layer similarly deforms and absorbs fine irregularities such as dust. Therefore, it is possible to reliably transfer the intended image to the intermediate transfer sheet with good dot reproducibility and improve the print quality. Also, when retransferring from the intermediate transfer sheet to the final image display substrate, In addition, since the soft resin layer is deformed, it is possible to satisfactorily retransfer even if the image display substrate has a surface unevenness such as paper.

[Brief description of the drawings]

FIG. 1 is a diagram showing a layer structure of an intermediate transfer sheet of the present invention.

FIG. 2 is a layer configuration diagram of another intermediate transfer sheet according to the present invention.

FIG. 3 is a diagram showing a layer structure of another intermediate transfer sheet of the present invention.

FIG. 4 is a diagram illustrating a layer structure of a conventional intermediate transfer sheet.

FIG. 5 is an explanatory diagram of an image forming method in sublimation transfer or hot melt transfer.

FIG. 6 is an explanatory diagram showing an example of a card having an image formed by thermal transfer recording.

[Description of Signs] 1 support 2 peelable protective layer 3 image receiving / adhesive layer 4 soft resin layer 5 forgery prevention layer 10, 10A, 10B, 10C intermediate transfer sheet 20 transfer ribbon 30 recording medium 31 color image 40 printer 41 platen Roller 42 Thermal head

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B44C 1/17 B41M 5/26 H

Claims (6)

[Claims] At least a peelable protective layer and an image-receiving / adhesive layer are sequentially laminated on a support, and the image-receiving / adhesive layer forms an image by thermal transfer recording and is used for an image display substrate. The intermediate transfer sheet, which is peeled off from the support when the image-receiving and adhesive layer is thermally bonded to the image display substrate and is adhered to the image display substrate, has a peeling property. An intermediate transfer sheet having a soft resin layer containing a resin having a 100% modulus of 80 kg / cm ² or less as a main component between a protective layer and an image receiving / adhesive layer. 2. The intermediate transfer sheet according to claim 1, wherein the soft resin layer is made of a polyurethane resin. 3. The intermediate transfer sheet according to claim 1, wherein the soft resin layer has a thickness of 1 to 30 μm. 4. A forgery prevention layer for increasing forgery difficulty is formed between the peelable protective layer and the soft resin layer.
4. The intermediate transfer sheet according to any one of 1. to 3., 5. An anti-counterfeiting layer for increasing counterfeiting difficulty is formed between the soft resin layer and the image-receiving / adhesive layer.
4. The intermediate transfer sheet according to any one of 1. to 3., 6. The intermediate transfer sheet according to claim 4, wherein the forgery prevention layer comprises a transparent hologram.