JPH0825787A - Transfer sheet - Google Patents

Abstract

PURPOSE:To obtain a transfer sheet which has excellent threading properties and stable peeling strength between a transfer layer and a mold release layer by specifying the thicknesses of the transfer layer and the release layer in the sheet having the transfer layer, the mold release layer and a support layer. CONSTITUTION:A heat transfer type transfer sheet can thermally print to decorate the pattern of a copying machine to cloth for clothings, a signboard, a shopwindow, etc., has a transfer layer, a mold release layer and a support layer so that the thicknesses of the transfer layer and the release layer are set to a range of 3-30mum. The release layer is formed as a thermoplastic resin mold release layer, thereby regulating a releasing strength to suppress a curl after printing. The resin is preferably ethylene resin, in which monomer content is about 17-40wt.%. Thus, the resin is used between the transfer layer and the support layer, thereby regulating the releasing strength between the transfer layer and the support layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer type printing machine capable of heat-decorating a pattern of a copying machine onto a print of clothing cloth or the like and a paper, plastic, glass or the like of a signboard, a show window or the like. It relates to a transfer sheet.

[0002]

2. Description of the Related Art Conventionally, screen printing, gravure printing and the like have been used as a method for decorating prints of cloths for clothing and prints of paper, plastic and glass such as signboards and show windows. With these printing methods, it is difficult to produce a small lot, and if this is done, the cost will increase considerably. Further, in the case of printing by the conventional method, it takes a long time to make an original plate, so that it is not possible to quickly meet the delivery date. Also in terms of image quality, the conventional image is considerably lacking in reproducibility of the original due to the unevenness of the material on the transferred side. Since the conventional printing method uses a solvent, the working environment is not good. On the other hand, recently, in addition to the above-mentioned printing method, there is a method in which an image of a color copying machine is copy-printed on a transfer sheet and the image is transferred by heat together with an EVA resin layer serving as a transfer layer. This has advantages over screen printing such as reproducibility of originals, reduction of preparation time, cost for small lot production, and no need for solvent. However, when an EVA resin is used as a transfer material, the adhesiveness with the material on the transferred side and the adhesive force with the pigment toner are insufficient, and it is difficult to use for a long period of time. In addition, when a resin other than EVA resin that has good adhesiveness to the material on the transfer side and adhesive strength to the pigment toner is used, peeling from the base paper or film after copying is difficult, Further, when a release agent such as silicone is applied to enable peeling from the paper or film as the base, the peel strength is extremely reduced, which makes control difficult.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is to provide a good transferred image, excellent paper-passability, easy thermal transfer, and a good texture and good texture after being melt-bonded to a material to be transferred. It is an object of the present invention to provide a transfer sheet for a copying machine, which can obtain a transfer image having air permeability. In addition, paper can be passed through the color copier without peeling between the transfer layer and the support layer, and the peel strength between the transfer layer and the support layer changes from that before transfer even after the image is thermally transferred to the adherend. The purpose of the present invention is to provide a transfer sheet having a low amount of the support layer and easily peeling the support layer.

[0004]

The point of the technique of the present invention is to adjust the peel strength, which is difficult to control with the current transfer sheets for copying machines. It is important to obtain a transfer sheet for a copying machine, which has the same peel strength even after heat-bonding with the material. As a result of investigating the release layer, the peel strength between the transfer layer and the supporting layer was successfully adjusted by using a thermoplastic resin between the transfer layer and the supporting layer. However, if the resin used for the release layer is crystallized and the dimension change such as shrinkage occurs, curling occurs when printing with a copying machine. The curl reduces workability at the time of printing and transferring to the material on the transferred side. In order to improve workability during printing and transfer, it is also important to eliminate curl after printing.

As a result of diligent studies on the release layer, the use of a thermoplastic resin release layer having the following characteristics makes it possible to adjust the peel strength and to obtain a transfer paper for a copying machine which does not curl after printing. I was able to get it.

An effective thermoplastic resin for the release layer is an ethylene resin, which has a copolymerization monomer content of 1: 1.
What is 7-40 wt%.

Further, by using a thermoplastic resin for the release layer, it is possible to form a film by the coextrusion method, and this makes it possible to reduce the thickness of the thermoadhesive resin layer. It is possible to supply a transfer sheet onto which an image has been transferred by thinning the heat-adhesive resin layer and which does not impair the texture of an adherend such as cloth.

[0008]

[Detailed Description of the Invention] The determination of the thermoplastic resin as the release layer will be described. When an image is formed on a transfer sheet by a copying machine, the thermoplastic resin that is the release layer is melted by the heat when fixing the toner, which is the image, and the thermoplastic resin of the release layer that is melted after being discharged from the copy machine. Is left at room temperature. Content of copolymerized monomer of ethylene resin is 1
If it is 7 wt% or less, crystallization of the release layer resin proceeds,
Curling occurs due to resin shrinkage. When the content of the copolymerization monomer is 40 wt% or more, the adhesiveness of the resin is strong and the performance as the release layer resin is insufficient. Further, in order to shorten the working time, when the transfer layer and the release layer are peeled off immediately after the transfer, since the melting point of this resin has dropped to near 50 ° C., the resin of the release layer is in a molten state, and the peeling is further performed. Becomes difficult and the performance as the release layer resin becomes insufficient.

The copolymerization monomer of the ethylene-based copolymer resin of the thermoplastic release resin in the present invention is an α-olefin-based / vinyl-based copolymerization monomer or the like. However, the vinyl-based copolymerization monomer excludes an acid, and is preferably a vinyl-based ester. For example, as a copolymer containing α-olefin as a constitutional unit, ethylene, propylene, butene-1, pentene-1, 3-methylpentene-1, 4-methylpentene-1, hexene-1, heptene-1, octene -1,
4-methyloctene-1, nonene-1 α-olefin copolymer having about 2 to 9 carbon atoms is exemplified. Preferred α-
The α-olefin copolymer having a carbon number of about 2 to 8 is included in the olefin copolymer. Further, for example, as a copolymer containing a vinyl-based copolymerization monomer constituent unit excluding an acid, a copolymer of vinyl acetate, methyl acrylate, ethyl acrylate, methyl methacrylate or the like is included.

The above-mentioned copolymerization monomers can be used alone or in combination of two or more kinds, and the above-mentioned copolymers can be used in combination of one kind or two or more kinds. The polymerization degree of the ethylene-based copolymer resin is not particularly limited and is usually 300
˜17,000, preferably about 3,000 to 12,000.

In the present invention, the thickness of the transfer layer is usually 3
˜30 μ, preferably 5 to 20 μ, and more preferably 7 to 15 μ. By setting the thickness of the transfer layer to 30 μm or less, preferably 20 μm or less, and more preferably 15 μm or less, good air permeability can be maintained even after transfer to a fiber material such as cotton or polyester.

The thickness of the release layer is usually 3 to 30.
μ, preferably 5 to 20 μ, more preferably 7 to
It is 15μ. When the thickness of the release layer is 3 μm or less, it is difficult to control the production because the thickness is too thin.
In the above case, the thickness is larger than the thickness of the transfer layer, which leads to a reduction in manufacturing speed and an increase in cost.

A small amount of an adhesive resin or a non-adhesive resin may be added to the release layer in the present invention in order to adjust the peel strength between the transfer layer and the release layer. An example of adding a small amount of adhesive resin is as follows. A typical non-EVA-based transfer layer is a polyurethane-based resin or a polyester-based resin, and as the adhesive resin for adjusting the peel strength, a polyurethane-based resin, a polyester-based resin, an acid-modified ethylene-based resin, or the like is used. Is.

The method for producing the transfer layer and the release layer in the present invention is a molten resin extrusion method, which may be either a T-die method or an inflation method, and at least the transfer layer and the release layer are coextrusion. preferable. Further, an adhesive resin with a sheet-like material that becomes a supporting layer is laminated by a coextrusion method, or another thermoplastic resin that becomes a supporting layer is laminated by a coextrusion method, so that the copier is suitable for paper passing. May be improved or the manufacturing process may be shortened.

[0015]

EFFECT OF THE INVENTION By determining the composition of the release layer resin as in the examples, it is possible to stabilize the peel strength between the transfer layer and the release layer and to supply a curl-free transfer sheet. I was able to. By using this transfer sheet, workability during printing, transfer, and peeling of the support layer was improved.
In addition, by using a thermoplastic resin for the release layer, it is possible to manufacture by a coextrusion method. Advantages of this manufacturing method are that the transfer layer can be stably thinned, the manufacturing process and time can be shortened, and the manufacturing can be performed at low cost. Further, stable thinning of the transfer layer makes it possible to obtain a texture similar to that of the original adherend in the transferred part and to obtain air permeability.

[0016]

Examples and Comparative Examples The transfer sheet was prepared as follows.

First, in a φ40 mm extruder, a thermoadhesive polyurethane hot-melt resin as a transfer layer, a thermoplastic resin as a release layer, and an adhesive resin for a release layer and a support layer are charged into three extruders, and they are fed into a feed block. Combined, width 600 mm
Co-extrusion was performed using the T-die of. This co-extruded film was laminated on 90 μ high-quality paper to form a transfer sheet.

An acid-modified ethylene ethyl acrylate resin was used as the adhesive resin between the release layer and the support layer.

Structure of transfer sheet: transfer layer / release layer / adhesive resin layer between release layer and support layer / high quality paper The method for evaluating the transfer sheet is as follows.

1. Peel strength between transfer layer and release layer before image printing.

2. Peel strength between the transfer layer and the release layer after transfer to the adherend.

3. The curl of the transfer sheet after fixing the toner was visually evaluated.

4. After the transfer layer was adhered using a cotton cloth as an adherend, breathability was determined by blowing a breath.

5. After using a cotton cloth for a T-shirt as an adherend to bond a printed transfer layer, the texture with the original cotton cloth was compared as a texture.

The peel strength is 200 mm at room temperature and the pulling speed is 200 mm.
/ Min, sample width 25 mm, and 180 ° peeling.

The structures of Examples 1 to 9 are as shown in Table 1.

The structures of Comparative Examples 1 to 12 are as shown in Table 2. (However, in the transfer sheet of Comparative Example 12, a single layer of the transfer layer was extrusion-laminated on the silicone release paper.) The evaluation results are shown in Table 3.

[0028]

[Table 1]

[Table 2]

[Table 3]

Claims (3)

[Claims] 1. A transfer sheet comprising a transfer layer / release layer / support layer, wherein the transfer layer and the release layer each have a thickness of 3 to 5.
A transfer sheet having a size of 30 μm. 2. The transfer sheet according to claim 1, wherein the release layer is a thermoplastic resin. 3. The transfer sheet according to claim 2, wherein the thermoplastic resin is an ethylene copolymer resin.