JPH0516527A - Multiple time printing method - Google Patents

Abstract

PURPOSE:To provide a multiple time printing method which can produce a good print at all times without requiring troublesome reverse resetting. CONSTITUTION:In the multiple time (n times) printing method employing a thermal transfer sheet having an ink layer composed of a coloring agent and a binder mainly composed of a wax and/or a low melting point resin on one surface of a basic material film, the thermal transfer sheet is carried by a predetermined length (L) while printing and then it is returned by a distance (n-1/n)XL thereafter it is carried again by the predetermined distance (L) while printing, and the operations are repeated. The multiple time printing method employing the thermal transfer sheet is characterized in that the thermal transfer sheet is carried by a predetermined distance while printing followed by returning thereof by same distance, the operation is repeated by predetermined times and then the operation is repeated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-printing method,
More specifically, the present invention relates to a multiple printing method that does not require resetting a thermal transfer sheet to be used multiple times.

[0002]

2. Description of the Related Art Conventionally, when printing an output print of a computer or a word processor by a thermal transfer system, a thermal transfer sheet having a heat-fusible ink layer on one surface of a base film is used. The above-mentioned conventional thermal transfer sheet is used as a base material film such as condenser paper or paraffin paper having a thickness of 10 to 20 μm or a thickness of 3 to 20.
It is manufactured by using a film of plastic such as polyester or cellophane having a thickness of μm, and coating a hot-melt ink layer in which a colorant such as a pigment or a dye is mixed with wax. The biggest drawback of the thermal transfer sheet is
This is very uneconomical, because only one printing is possible in the same area of the thermal transfer sheet. That is, in the case of a type ink ribbon in which a cloth tape which has been conventionally used is impregnated with ink, it is possible to perform printing more than once in the same area, whereas in the case of a thermal transfer sheet, it is possible to print once. Since the ink layer of the printed part is completely transferred by printing, 2 at the same position
Printing cannot be performed more than once, and the base material sheet used for the thermal transfer sheet becomes a disposable state once. Also, the amount of ink actually transferred to the transfer material is only a few percent, at most a dozen percent of the total ink amount of the thermal transfer sheet, and most other inks are discarded without being used. .

As a solution to such a problem, a thermal transfer sheet capable of printing many times has been proposed. As such a multi-use thermal transfer sheet, a type in which an ink layer is impregnated with a porous resin layer to gradually use the ink, a type in which a porous coating is formed on the surface of the ink layer, an ink layer and a base film are used. Many types have been proposed, such as a type in which an adhesive layer is provided therebetween, a type in which ink layers are provided in multiple layers with binders having different softening points, and a type in which a transfer control layer is provided on the surface of the ink layer. The multi-printing method using the thermal transfer sheet for multi-printing described above is usually stored in a cassette integrally formed with a winding core wound around the transfer sheet and a winding core for winding up the winding during printing. Then, the cassette is attached to the printer, printing is performed while winding the thermal transfer sheet around the winding core, and after the thermal transfer sheet is used substantially, the cassette is reversed and wound around the original core. Printing is performed and this operation is performed a plurality of times, which is a conventional multiple printing method.

[0004]

In the above-mentioned conventional method, one printing is completed because the heat transfer sheet has fine irregularities or wrinkles in the first printing due to the thermal pressure of the thermal head. The roll formed by winding in the state of having a tendency to have a larger diameter than that of the roll before the first use because of its low winding pressure.
As a result, there is a problem that as the number of times of printing increases from the second time onward, printing defects occur due to the influence of running stability of the thermal transfer sheet and wrinkles that have occurred up to that time. Also, reversing and reattaching the cassette after each use is a complicated operation,
In connection with this, if confirmation of the number of times of use is required, or if the number of times of printing is erroneously exceeded, a variety of problems occur, such as a print having a poor density. Therefore, an object of the present invention is to solve the above-mentioned drawbacks and to provide a multiple printing method capable of always performing good printing without requiring a complicated reverse reset of the cassette.

[0005]

The above object can be achieved by the present invention described below. That is, the present invention is a multi-time (n times) printing method using a thermal transfer sheet in which an ink layer composed of a binder containing a wax and / or a low melting point resin as a main component and a colorant is provided on one surface of a base film. At
After transferring the thermal transfer sheet for a predetermined distance (L) while printing,
After returning the distance of (n−1 / n) × L, the thermal transfer sheet is conveyed by a predetermined distance (L) for printing while printing again, and printing is performed, and this operation is repeated.
And a multi-step printing method using the thermal transfer sheet, characterized in that the thermal transfer sheet is conveyed a predetermined distance while printing, and is returned to the same distance, this operation is repeated a predetermined number of times, and the above operation is repeated again after the predetermined number of times. This is a one-time printing method.

[0006]

[Advantages] According to the method as described above, unevenness occurs on the thermal transfer sheet according to the number of times of printing, wrinkles are generated during winding, and the roll diameter of the thermal transfer sheet wound on the take-up roll is enlarged. However, the printing defect as in the prior art does not occur. Further, it is not necessary to reversely reset the cassette for each print count, and there is no room for various problems caused by the reverse reset. Further, by instructing the printer side the number of times of printing to be used, printing is not performed a predetermined number of times or more, and the problem of insufficient density printing does not occur.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in more detail with reference to the preferred embodiments. The basic form of the method of the present invention will be described with reference to FIGS. 1a and 1b. In FIG. 1a,
The printer contains a disposable cassette 2 containing a thermal transfer sheet 1 for printing multiple times. A thermal head 3 is set on the back side of the thermal transfer sheet 1, while a platen 4 is provided on the ink layer side of the thermal transfer sheet 1, and a paper 5 which is a transfer target material is provided between the platen 4 and the thermal transfer sheet 1. (Vertical A4 size plain paper in this example) is set. In the conventional method, the thermal transfer sheet 1 wound in the form of a roll on the winding core 6 is wound on the winding winding core 7 and proceeds in the direction of the solid line arrow, and the paper 5 is printed one after another, and almost all of the thermal transfer sheet 1 is printed. The state of being wound around the winding core 7 (FIG. 1b) is reached, and the first printing is completed. Then, the cassette 2 is removed from the printer, the reverse rotation is reset, the state shown in FIG. 1 is restored, the second printing is performed, and this operation is repeated a predetermined number of times.

In the first method of the present invention, as shown in FIG. 1a, the paper 5 and the thermal transfer sheet 1 are conveyed in the same direction and printed on the paper 5 as described above. When the thermal transfer sheet 1 being used is for printing three times (n times) at the time when the printing of the paper 5 is completed, the thermal transfer sheet is 2/3 {[(n (1 / n)] × [print length of paper (L)]}, rewind for the second printing, and feed the next paper 5 to a predetermined position to perform thermal transfer as described above. The sheets are sequentially fed and a new printing is performed on the new paper 5. Hereinafter, the same operation as described above is repeated until the thermal transfer sheet is used up. In the second method of the present invention, as shown in FIG. 1a, the paper 5 and the thermal transfer sheet 1 are conveyed in the same direction and printed on the paper 5 as described above. When the printing of this paper 5 is completed, the thermal transfer sheet 1 in use is fed back by the length corresponding to the used length as indicated by the dotted line arrow to prepare for the second printing,
Then, the next paper 5 is fed to a predetermined position, and the new paper 5 is printed for the second time in the same manner as above. After carrying out this operation a predetermined number of times, the thermal transfer sheet 1 is not fed backward but is fed forward by a prescribed length (for example, the length of the paper) in the direction of the solid line arrow, that is, with a fresh ink layer on the next page. The first printing is performed on the paper 5, the printing is performed a predetermined number of times as described above, and the same operation is repeated thereafter.

Therefore, according to the above method, when all the thermal transfer sheets 1 are wound on the winding core 7 (FIG. 1b), the thermal transfer sheets 1 are subjected to a predetermined number of times on substantially all surfaces. Since printing is performed, it is not necessary to reset the cassette 2 in the reverse direction, and the above-described operational effects can be easily achieved. In the first method, the length of the reverse transfer of the thermal transfer sheet varies depending on how many times (n times) the thermal transfer sheet is used for printing, and the optimum reverse transfer length is [the length of the sheet printing paper]. ×
[N-1 / n], and when the material to be transferred is a long type such as roll paper, the length before and after the roll interval in the cassette, for example, about 10 to 50 cm is common. is there.
Of course, the method of the present invention is not limited to this width or length. In the second method, when a sheet-type paper is used as the transfer material, the width or length is almost the same as the printing width (or length) of the transfer material. Preferably
When the material to be transferred is a long type such as a roll paper, the length before and after the roll interval in the cassette, for example, 10 to
It is generally about 50 cm. Of course, the method of the present invention is not limited to this width or length.

The printer used in the present invention may be substantially the same as a conventionally known printer, and only needs to be provided with a device capable of feeding back the thermal transfer sheet by a predetermined length. Further, the thermal transfer sheet for multi-use printing used in the present invention is a type in which the ink layer is gradually used by impregnating the ink layer with the porous resin layer as described above, and a porous coating is formed on the surface of the ink layer. Conventionally known types, such as a type in which an adhesive layer is provided between the ink layer and the base film, a type in which the ink layers are provided in multiple layers with binders having different softening points, a type in which a transfer control layer is provided on the surface of the ink layer, etc. Any of the multiple times thermal transfer sheets for printing may be used. The material to be transferred used in the present invention is also a conventionally known sheet-type or roll-type paper,
It may be any transfer material such as a plastic film sheet or synthetic paper.

[0011]

EXAMPLES Next, the present invention will be described more specifically with reference to examples. In addition, unless otherwise specified, "parts" and "%" in the text are based on weight. Example 1 A polyethylene terephthalate film having a thickness of 6.0 μm was used as a base film, and a material for forming a porous layer having the following composition was applied and dried on one surface of the base film at a rate of 8 μm when dried, and further at 50 ° C. Aging was performed for 3 days to form a porous layer having a porosity of about 80%. Porous layer forming material Potassium titanate short fiber (Tismo D, Otsuka Chemical, length 10 to 20 μm, fiber diameter 0.2 to 0.3 μm, true specific gravity 3.3) 5 parts by volume Linear saturated polyester resin (Vylon 280, Toyobo) ) 10 parts by volume Methyl ethyl ketone / toluene (1/1) 50 parts by volume A heat-meltable ink comprising the following components was kneaded at 120 ° C. for 6 hours, and then the hot melt roll coating method at an ink temperature of 120 ° C. was applied to the above porous layer. Was applied at a rate of 6 g / m ² (dry state), impregnated and held to obtain a thermal transfer sheet used in the present invention. Heat-fusible ink layer Carbon black (Dia Black G, manufactured by Mitsubishi Kasei) 15 parts Ethylene / vinyl acetate copolymer (EVA Flex 310, manufactured by Mitsui Polychemicals) 8 parts Paraffin wax (paraffin 150F, manufactured by Nippon Seiro Co., Ltd.) 50 parts Carnauba wax 25 parts

Example 2 Polyester resin (Vylonal 1930, manufactured by Toyobo) 10 parts Carnauba wax (WE-90, manufactured by bond wax) 10 parts Polyethylene wax (melting point 140 ° C., particle size 0.01 to 5 μm) 10 parts Carbon black (# 30, manufactured by Mitsubishi Kasei) 10 parts Nonionic surfactant 1 part Isopropanol 30 parts Water 100 parts An aqueous emulsion of the above composition is provided with a heat-resistant slip layer on the back surface at a rate of 6 g / m ^{2 based on} the solid content by a gravure roll method. It was applied to a polyester film having a thickness of 6 μm and dried at a temperature of about 80 ° C. to 90 ° C. to obtain a thermal transfer sheet for multi-use printing used in the present invention.

Use Example 1 Thermal transfer sheet and A4 size PPC paper (lengthwise) of the above embodiment
After printing the A4 size printing area (301 mm) once, the length of 3/4 of the printing area is returned and the thermal transfer sheet is conveyed again over the same printing length. When printing was carried out a number of times (4 times) under the following printing conditions by the method of the invention, the printed products all had excellent printing quality. Use Example 2 Thermal transfer sheet and A4 size PPC paper (lengthwise) of the above embodiment
When an IC that feeds back every 4 times every 301 mm is installed in a printer conveying device using the above, and the printing is performed a number of times under the following printing conditions by the method of the present invention, the printed matter has excellent printing quality. Had. Printing conditions Equipment used: Toshiba Simulator equipped with a thin-film thermal head Printing energy: 0.8 mJ / dott (constant)

[0014]

[Advantages] According to the method as described above, unevenness occurs on the thermal transfer sheet according to the number of times of printing, wrinkles are generated during winding, and the roll diameter of the thermal transfer sheet wound on the take-up roll is enlarged. However, the printing defect as in the prior art does not occur. Further, it is not necessary to reversely reset the cassette for each print count, and there is no room for various problems caused by the reverse reset. Further, by instructing the printer side the number of times of printing to be used, printing is not performed a predetermined number of times or more, and the problem of insufficient density printing does not occur.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the present invention.

[Explanation of symbols]

1: Thermal transfer sheet 2: cassette 3: Thermal head 4: Platen 5: Paper 6,7: winding core

Claims (4)

[Claims] 1. A multi-time (n times) printing method using a thermal transfer sheet in which an ink layer composed of a binder containing a wax and / or a low melting point resin as a main component and a colorant is provided on one surface of a base film. After the thermal transfer sheet is conveyed by a predetermined distance (L) while printing, the distance of (n-1 / n) × L is returned, and then the thermal transfer sheet is conveyed by a predetermined distance (L) while printing again to print. A multi-printing method characterized by repeating operations. 2. The multi-time printing method using a thermal transfer sheet according to claim 1, wherein the thermal transfer sheet is conveyed for a predetermined distance while printing and then returned to the same distance, this operation is repeated a predetermined number of times, and the above operation is repeated again after a predetermined number of times. A multi-printing method characterized by repeating. 3. The multiple printing method according to claim 1, wherein the thermal transfer sheet is stored in a cassette. 4. The multiple printing method according to claim 2, wherein the predetermined distance is substantially the same as the printing width of the sheet-type transfer material.