JPH03203697A - Rolled composite thermal transfer sheet - Google Patents

Abstract

PURPOSE:To enhance adhesion and release properties and prevent troubles from occurring in paper feeding or printing, by securely adhering a leading end part of a rolled form composite thermal transfer sheet having a receiving material tentatively adhered to a thermal transfer film. CONSTITUTION:A thermal transfer film A having a meltable ink layer 2 provided on one side of a base film 1 and a receiving material B having substantially the same width as that of the film A are releasably adhered to each other by a tentative adhesive layer 3, and are wound into a roll, with leading end parts of the films A and B being securely adhered to each other. With the leading end parts thus adhered securely, this composite thermal transfer sheet can be supplied to a printer while preventing such troubles as release and levitation of the leading end parts or wrinkling from occurring during the passage of the sheet to supply rollers 11, a feed roller 12 or a printing part comprising a thermal head 13 and a platen roll 14.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a rolled composite thermal transfer sheet, and more specifically, a novel rolled composite thermal transfer sheet in which a thermal transfer film and a transfer material such as paper are temporarily bonded in advance. Regarding the seat.

(Prior art and its problems) Conventionally, when printing output prints from computers and word processors using a thermal transfer method, a thermal transfer film with a heat-melting ink layer provided on one side of a base film has been used. .

This conventional thermal transfer film uses a paper such as capacitor paper or paraffin paper with a thickness of 10 to 2 OLLm, or a plastic film such as polyester or cellophane with a thickness of 3 to 20 gm as a base film, and pigments or dyes are added to the wax. It is manufactured by coating a layer of hot-melt ink containing a colorant such as .

When printing on transfer paper using these conventional thermal transfer films, the thermal transfer film is supplied from a roll wrapped with a long thermal transfer film, and a continuous or sheet transfer material is supplied, and both are stacked on a platen, and in this state heat is applied from the back side of the thermal transfer film using a thermal head to melt and transfer the ink layer to form a desired image.

However, if these thermal transfer films were to be used in facsimile printers that use conventional heat-sensitive coloring paper, for example, the above-mentioned Tsukushimi Rib Nontar does not have a conveyance device for the transfer material because the recording paper itself is colored by heat. This problem also applies to special printers such as large block printers.

As a method to solve the above-mentioned problems, the thermal transfer film and the material to be transferred are temporarily bonded in advance and wound into a roll to make it suitable for facsimile printers, etc.
Additionally, methods have been proposed for simplifying and downsizing the device.

In the case of such co-wound multiple heat-containing transfer sheets, the heat transfer film and paper adhere firmly to each other, preventing wrinkles or misalignment of the heat transfer film, and furthermore, after heat transfer, both are easily peeled off and the transfer area is The ink layer is required to be accurately transferred to the paper, and the ink layer is not transferred at all in the transfer area so that the paper is not contaminated.

Therefore, in a sense, both of them are easy to separate, so the leading edge of these composite thermal transfer sheets tends to separate from the thermal transfer film and the transfer material, making it difficult to feed the paper to the printer properly.
Alternatively, there is a problem in that the thermal transfer film is lifted or wrinkled, making it impossible to print well.

Therefore, an object of the present invention is to solve the above problems and provide a rolled composite thermal transfer sheet that is excellent in both adhesiveness and releasability, and is free from paper feeding troubles and printing troubles.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, in the present invention, a thermal transfer film having a heat-melting ink layer formed on one side of a base film and a transfer material having substantially the same width are releasably adhered to each other by a temporary adhesive layer, and then rolled. This is a roll-shaped composite thermal transfer sheet characterized in that the leading end portions of the composite thermal transfer sheet are fixed.

(Function) By fixing the tip of the roll-shaped composite thermal transfer sheet in which the transferred material is temporarily adhered to the thermal transfer film, it is possible to create a roll that has excellent both adhesion and peelability, and is free from paper feeding and printing problems. A composite thermal transfer sheet is provided.

(Preferred Embodiments) Next, the present invention will be described in more detail by citing preferred embodiments.

The roll-shaped composite thermal transfer sheet of the present invention, as shown in a part of its cross section in FIG. The transfer material B having the same width as the upper part is releasably adhered by a temporary adhesive layer 3, and is wound into a roll as shown in Fig. 2, and the tip thereof is as shown in Figs. 3 and 4. It is characterized by being firmly fixed.

By fixing the leading edge in this way, when this composite thermal transfer sheet is fed to the printer as shown in the first figure, it is possible to remove the paper from the paper feed roll 11, conveyance roll 12, thermal head 13, and platen roll 14. It is possible to prevent troubles such as the tip of the printed part peeling off and floating or wrinkles occurring during the printing process.

Although the object of the present invention can be achieved even if the leading end of the composite thermal transfer sheet of the present invention is fixed with an adhesive or the like in a state where the thermal transfer film A and the transferred material B have the same length, in a preferred embodiment, As shown in the second to fourth figures, it is preferable to shorten the thermal transfer film A at the tip and fix the tip of the thermal transfer film A to the transfer material B in this state. By doing this, the leading end of the transferred material B can act as a lead paper, and there is no need to specially prepare the lead paper.

The example shown in the third figure is an example in which the leading end of the thermal transfer film A is fixed to the transferred material B by heat sealing, and in this case, a temporary adhesive layer is formed between the thermal transfer film A and the transferred material B. , the two can be fixed together simply by heating and pressing the ends. Instead of heat sealing, it may be adhered with another adhesive, or the two may be engaged with each other using a clipless method or the like.

The example shown in FIG. 4 is another preferred embodiment, and is an example in which a thermal transfer film A is fixed to a transfer material B with a normal adhesive tape 4. In this example, when supplied to a printer as shown in the first figure, the adhesive tape 4 can be peeled off after printing, and the used amount of thermal transfer film A can be easily fixed to the take-up roll 15 with the adhesive tape 4.

The shape of the tip of the transferred material as described above may be vertical as shown in FIG. 2, but the tip may be narrowed as shown in FIGS. You can.

Furthermore, in a preferred embodiment of the present invention, as shown in FIG. 6 and FIG. 7, which is a cross-sectional view thereof, a detection mark 5 is formed on the surface of the transferred material B at the end of the composite thermal transfer sheet. Trouble caused by running out of the composite thermal transfer sheet can be prevented. For example, the detection mark 5 may be colored in any desired color so that it can be recognized with the naked eye.In addition to coloring, a hole 6 may be provided at the end of the composite thermal transfer sheet as shown in FIG. The end may be detected. Of course, even if it is a colored detection mark, the end can be detected by optical means and the printer can be automatically stopped.

The present invention has been described above by citing several embodiments, but
It goes without saying that the present invention is not limited to these embodiments, and that the leading end of the composite thermal transfer sheet may be fixed by other methods.

As the base film 1 used in the composite thermal transfer sheet of the present invention as described above, the same base film used for conventional thermal transfer films can be used as is, and other materials can also be used. , not particularly limited.

Specific examples of preferred base films include polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride,
Polystyrene, nylon, polyimide, polyvinylidene chloride, polyvinyl alcohol, fluororesin, chlorinated rubber,
Examples include plastics such as ionomers, papers such as condenser paper and paraffin paper, nonwoven fabrics, and base films made of composites of these materials.

The thickness of this base film can be changed as appropriate depending on the material so that its strength and thermal conductivity are appropriate, but the thickness is preferably, for example, 2 to 25 μm.

The heat-melting ink layer 2 provided on the base film l is
It consists of a coloring agent and a vehicle, and various additives may be added as necessary.

The coloring agent is preferably an organic or inorganic pigment or dye that has good properties as a recording material, for example, one that has sufficient color density and does not discolor or fade due to light, heat, temperature, etc.

Of course, carbon black is preferable for black monochrome printing, and chromatic colorants such as cyan, magenta, yellow, etc. are used for multicolor printing. It is generally preferred that these colorants be used in an amount of about 5 to 70% by weight in the ink layer.

The vehicle used includes wax as a main component, and mixtures of wax with drying oil, resin, mineral oil, cellulose, rubber derivatives, and the like.

Representative examples of wax include microcrystalline wax, carnauba wax, paraffin wax, and the like. In addition, Fischer-Tropsch wax, various low molecular weight polyethylenes, wood wax, beeswax, spermaceti wax, privet wax, wool wax, shellac wax, candelilla wax, petrolactam, polyester wax, partially modified waxes, fatty acid esters, fatty acid amides, etc. wax is used. In the present invention, a thermoplastic resin having a relatively low melting point may be mixed into the wax to improve the adhesion of the ink to the transfer material.

Methods for forming a hot melt ink layer on a base film include hot melt coating, hot lacquer coating,
Examples include gravure coating, gravure reverse coating, roll coating and many other methods. The thickness of these ink layers may be several micrometers as in the conventional case.

Transfer material B may be any sheet or film that can be thermally transferred, such as normal high-quality paper, plain paper, synthetic paper, tracing paper, plastic film, etc., and is not a sheet or film that is used as a conventional transfer material for thermal transfer. Good to have.

The temporary adhesive layer 3 for temporarily adhering the thermal transfer film A and the material to be transferred B is formed of an adhesive that lightly adheres the thermal transfer film and the material to be transferred, and can easily separate the two after printing. Although any adhesive can be used as long as it has such a function, a particularly preferred adhesive is composed of adhesive particles having a low glass transition temperature, resin particles having a high glass transition temperature, and wax particles.

The glass transition temperature of the above-mentioned adhesive is preferably in the range of -90°C to -60°C, and examples of such adhesives include rubber-based adhesives, acrylic-based adhesives, silicone-based adhesives, Furthermore, in terms of form, there are solvent-soluble acid type, water-soluble 7-day type, hot melt type, and water-based or oil-based emulsion type, all of which can be used in the present invention, but acrylic is particularly suitable for the present invention. It is an aqueous emulsion type system, and its particle size is about 0.2 to 10 μm, with a preferable range of 1 to 6 μm. By using such an emulsion-type adhesive, the adhesive in the adhesive layer maintains its particle shape.

When the above adhesive is used alone, excellent adhesion can be obtained, but the peelability of the transferred material is insufficient and uneven, and unexpected stress may be applied during manufacturing, storage, transportation, etc. before thermal transfer. If this is added, there is a problem in that the ink layer of the composite thermal transfer sheet is transferred to the transfer material, resulting in scumming. Furthermore, during thermal transfer, the ink layer is not easily cut, and, for example, the ink layer is transferred to the periphery of the area where heat is applied by the thermal head, resulting in poor resolution of the transferred image.

In the present invention, the above problem can be solved by adding a resin emulsion containing fine resin particles, for example, resin particles with a particle size of about 0.01 to 0.5 μm, to the emulsion pressure-sensitive adhesive, so that the tackiness can be reduced to a preferable range. This solves the background smudge problem, and by adding a wax emulsion like the one used to form the ink layer, the temporary adhesive layer's foil breakage is improved, and the resolution of the transferred image is significantly improved. I found that it can be improved.

As the above resin emulsion, for example, ethylene-
Thermoplastic resins such as vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, polyethylene, polystyrene, polypropylene, polybdenum, vinyl chloride resin, vinyl chloride-vinyl acetate copolymer, acrylic resin, and especially acrylic emulsion are preferred. be. Such resin particles preferably have a glass transition temperature higher than that of the pressure-sensitive adhesive, for example, 60° C. or higher, and may be thermoset resin particles as the case may be.

Further, the wax emulsion is obtained by emulsifying the above-mentioned wax by a known method, and the particle size is not particularly limited, although the finer the particle size, the better.

The weight ratio of the adhesive, resin particles, and wax is 3 to 5.
:1 to 2.5:3 to 5 is preferable. If the ratio is outside this range, the various problems described above are likely to occur, which is not preferable.

The temporary adhesive layer 3 made of the above components may be provided on the surface of the transfer material B, but in this case, since the printed matter remains sticky, it should be provided on the surface of the ink layer 2 of the thermal transfer film A. is preferable, and in this case, since the adhesive is used as an aqueous emulsion, it is preferable because the ink layer is not damaged. The emulsion coating method and drying method are not particularly limited, but drying is preferably performed at a low temperature so that emulsion particles remain.

The thickness of the temporary adhesive layer is preferably 0.1 to 20 μm (0.1 to 5 g/rr as solid coating amount).

The adhesion between the thermal transfer film A and the transferred material B is preferably performed by continuously adhering the transferred material while forming a temporary adhesive layer on the surface of the ink layer of the thermal transfer film, and then winding this up into a roll. When it is rolled up, the material to be transferred may be placed on the outside, or the thermal transfer film may be placed on the outside.

Next, after forming a detection mark as described above on the edge of the leading edge of this composite thermal transfer sheet on the side of the transfer material, as necessary, it is cut into a desired width and wound onto another paper tube, and finally, the By fixing the leading edge as described above, the rolled composite thermal transfer sheet of the present invention can be obtained.

The above is the basic structure of the roll-shaped composite thermal transfer sheet of the present invention, but it goes without saying that a slip layer is provided on the back side of the thermal transfer film to prevent the thermal head from adhering and to improve slipperiness, and a base film and ink layer are provided on the back side of the thermal transfer film. All of the well-known techniques in the thermal transfer film field can be added to the roll-shaped composite thermal transfer sheet of the present invention, such as making the print matte by providing a matte layer between the sheets and making the ink layer a color other than black. You can.

(Effects) According to the present invention as described above, in the roll-shaped composite thermal transfer sheet in which the transferred material is temporarily adhered to the thermal transfer film, by fixing the leading end thereof, it is possible to achieve both excellent adhesion and releasability, and A roll-shaped composite thermal transfer sheet that is free from paper feeding troubles and printing troubles is provided.

In a particularly preferred embodiment, the thermal transfer film at the leading edge is shortened and the long transfer material portion is used as a lead paper, so that the leading edge can be easily fed into the printer without the need to attach a special lead paper. I can do it.

Further, in another preferred embodiment, printing troubles can be prevented by providing a detection mark on the transfer material at the end of the composite thermal transfer sheet to notify that it is the end.

(Example) Next, the present invention will be described in more detail with reference to Examples. In the text, parts or percentages are based on weight unless otherwise specified.

Example 1 A base film of polyethylene terephthalate with a thickness of 6.0 μm and a slip layer provided on the back side was used, and the following ink composition was coated on one side at a rate of 4 g/d, An ink layer was formed.

±Z Tonagi Orotori carbon black 15 parts ethylene/vinyl acetate copolymer 8 parts paraffin wax 50 parts carnauba wax
25 parts (produced by kneading at 120°C for 4 hours with an attritor) Further, on the above ink layer, a temporary adhesive of the following composition was applied by gravure coating at a rate such that the coating amount when dry was 0.5 g/d. A temporary adhesive layer was formed by coating.

Kakari Toyotari plate acrylic adhesive particles aqueous dispersion (solid content 40
%, glass transition 4 degrees - 70 degrees Celsius, particle size.

3 to 10 tLm) 10 parts acrylic resin particles aqueous dispersion (solid content 20%,
Glass transition temperature 85℃, particle size 0.2 to 0.5μm)
15 parts carnauba wax aqueous dispersion (solid content 40%, melting point 83°C)
15 parts water
10 parts isopropanol 30
The above thermal transfer film and plain paper (basis weight 64 g/board, Beck surface smoothness 140 sec) were bonded together at a nip temperature of 50° C. and a nip thickness of 500 kg, and then wound up into a roll.

Next, a detection mark with a width of 1 cm and a length of 50 cm is printed on the edge of the rolled composite thermal transfer sheet on the side of the transferred material, and then it is cut into another paper tube and rolled up, and finally the thermal transfer film on the tip of the rolled composite thermal transfer sheet is printed. The paper was cut to a width of 15 cm, and the tip of the thermal transfer film was fixed to the paper surface with cellophane adhesive tape to obtain a composite thermal transfer sheet of the present invention.

The leading edge of the above composite thermal transfer sheet is sufficiently fixed so that it will not peel off during handling, and the thermal transfer film and paper will not shift, lift, or wrinkle when inserted into the printer or during printing. There was nothing to do.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the state of printing using a composite thermal transfer sheet, and FIGS. 2 to 8 are diagrams illustratively explaining the composite thermal transfer sheet of the present invention. A: 1: 3: 11゜13: Thermal transfer film base film Temporary adhesive layer detection mark 12.14, 15: Thermal helad B: Transferred material 2: Ink layer 4: Adhesive tape 6: Hole roll Figure 2

Claims (3)

[Claims] (1) A thermal transfer film with a hot-melt ink layer formed on one side of the base film and a material to be transferred having substantially the same width are releasably adhered with a temporary adhesive layer and wound into a roll. 1. A roll-shaped composite thermal transfer sheet, characterized in that the tip portions of the rolled composite thermal transfer sheet are fixed. (2) The rolled composite thermal transfer sheet according to claim 1, wherein either one of the thermal transfer film and the transfer material is longer than the other, and the tip of the shorter one is fixed to the other. (3) The rolled composite thermal transfer sheet according to claim 1, wherein an end detection mark is provided on the transferred material at the end of the thermal transfer sheet.