JPH0671917A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To print letters uniformly with the good quality on a paper of the rough surface in a halftone transfer method. CONSTITUTION:An intermediate transfer body is heated by a heating means 2. A thermal head 3 is a real edge type. An ink of a film is sequentially transferred from an ink ribbon 6 to the intermediate transfer body and from the intermediate transfer body to a paper 9. Accordingly, the ink is uniformly adhered and transferred to the paper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer for transferring the ink of an ink ribbon onto a sheet by the heat of a thermal head for printing, and more particularly to transferring the ink of the ink ribbon to an intermediate transfer member by the thermal head. The present invention relates to an intermediate transfer type thermal transfer printer that forms a primary recording image by re-transferring the primary recording image onto a sheet to perform desired printing.

[0002]

2. Description of the Related Art Conventionally, many thermal transfer printers have been used which perform printing in a state where a thermal head is pressed against a platen via a paper and an ink ribbon. In such a thermal transfer printer, a bond paper or the like is used. When printing on a paper having a rough surface, it is necessary to press the thermal head with a strong pressing force, but the pressing force of the thermal head is limited due to its precise structure. Therefore, the heat of the thermal head partially melts the ink of the ink ribbon and transfers it to the intermediate transfer member to form a primary recording image on the intermediate transfer member. 2. Description of the Related Art An intermediate transfer type thermal transfer printer is used in which an intermediate transfer member is transferred to a sheet by a pressure roller that presses the intermediate transfer body against the sheet with a pressing force.

FIG. 3 shows an outline of such a conventional intermediate transfer type thermal transfer printer.
A cylindrical intermediate transfer roller 1 that constitutes an intermediate transfer member is rotatably arranged, and a heater 2 for heating the intermediate transfer roller 1 to a predetermined temperature is provided inside the intermediate transfer roller 1. It is built in. A thermal head 3 is arranged near the intermediate transfer roller 1. The thermal head 3 is provided with a plurality of heating elements 4 arranged in a straight line so as to face the central portion of the intermediate transfer roller 1. On both sides of the thermal head 3, ink is applied to the bobbins 5. A pair of ribbon rolls 7 formed by winding a ribbon 6 and guiding the ink ribbon 6 between the intermediate transfer roller 1 and the thermal head 3 in a substantially linear manner.
A and 7B are arranged. Of these, ribbon roll 7
A is the supply side, and the ribbon roll 7B is the winding side. Further, a pressure roller 8 which is pressed against the intermediate transfer roller 1 with a strong pressing force is rotatably arranged at a position symmetrical in the diameter direction of the intermediate transfer roller 1 with respect to the thermal head 3. A predetermined paper 9 such as plain paper is inserted between the intermediate transfer roller 1 and the pressure roller 8 and the intermediate transfer roller 1 is rotated to drive the paper 9 to the intermediate transfer roller 1 and the pressure roller 8. It is sandwiched between and and conveyed in the direction opposite to the running direction of the ink ribbon 6.

According to the above-mentioned conventional thermal transfer printer,
A sheet of paper 9 is placed between the intermediate transfer roller 1 and the pressure roller 8.
When the pressure roller 8 is pressed against the intermediate transfer roller 1 with a strong pressing force, the thermal head 3 is pressed against the intermediate transfer roller 1, and the intermediate transfer roller 1 is driven to rotate in this state. Ribbon roll 7 on the winding side while carrying 9
While winding the ink ribbon 6 at a predetermined speed by B, the thermal head 3 is driven based on desired print data. As a result, the heating element 4 of the thermal head 3 generates heat and the ink of the ink ribbon 6 is partially melted and transferred to the surface of the intermediate transfer roller 1 to form a primary recording image. At this time, the primary recording image formed on the surface of the intermediate transfer roller 1 has only to be held on the intermediate transfer roller 1, and since the surface of the intermediate transfer roller is smooth, the thermal head 3 is moved to the intermediate transfer roller 1. It is not necessary to press it with such a strong pressure.

Then, the heater 2 of the intermediate transfer roller 1
While the ink transferred to the intermediate transfer roller 1 is heated to a constant temperature to cause the ink to have a certain degree of viscosity, the primary recording image of the intermediate transfer roller 1 is applied to the sheet 9 by the pressure contact force of the pressure roller 8. Reprinting can be performed and desired printing can be performed on the sheet 9. As a result, the pressure roller 8 re-transfers to the paper 9 with a strong pressure contact force, so that printing can be performed even on the paper 9 having a rough surface such as bond paper.

[0006]

By the way, in the thermal transfer printer of the intermediate transfer system having the above-mentioned structure, the heating element 4 of the thermal head 3 generates heat to partially melt the ink of the ink ribbon 6, and the intermediate transfer roller The peeling of the ink ribbon 6 from the intermediate transfer roller 1 when the primary recording image was formed by being transferred to the surface of No. 1 was supposed to be after the ink melted by the heat generated by the heating element 4 was cooled. Peeling of the ink ribbon at such a timing is referred to as cold peeling, and is a peeling method that opposes hot peeling in which peeling is performed when the ink is still in a molten state.

For the peeling of the ink ribbon 6 in the cold state, a wax type ink has been used in order to improve the printing quality. However, since this wax-based ink does not form a film even if it is melted by the heat generated by the heating element 4, voids may be generated and good quality printing can be performed on the paper 9 having a rough surface. There wasn't. In addition, ink may remain on the intermediate transfer roller 1.

Therefore, the paper 9 having the above-mentioned rough surface is used.
It has been found that the ink itself needs to be of a resin type capable of forming a film state by the heat generation of the heating element of the thermal head in order to uniformly adhere the ink onto the surface.

Due to its characteristics, the resin-based ink is transferred to the print medium (intermediate transfer roller 1) only when the ink of the ink ribbon 6 is melted by the heat energy generated from the heating element 4 of the thermal head 3. Is possible. On the other hand, according to the experiments conducted so far, the time during which the ink is maintained in the molten state is 5 msec which is very short from the time when the heat energy from the heating element 4 is obtained. However, it has been difficult to perform thermal peeling with an ink ribbon having a resin-based ink.

In view of the above points, it is an object of the present invention to provide a thermal transfer printer capable of uniformly printing good quality on a paper having a rough surface in the intermediate transfer method.

[0011]

In order to achieve the above-mentioned object, a thermal transfer printer of the present invention has a heating element arranged on an insulating substrate and partially melts ink of an ink ribbon according to print data. An ink ribbon is interposed between the thermal head and the intermediate transfer member heated by the heating means, and a pressure roller that is brought into pressure contact with the intermediate transfer member is arranged, and the ink of the ink ribbon is transferred by the thermal head. A primary recording image is formed by transferring to the intermediate transfer body, and the primary recording image of the intermediate transfer body is transferred to a sheet inserted between the intermediate transfer body and the pressure roller by the pressure contact force of the pressure roller. In a thermal transfer printer that performs desired printing, the ink ribbon at the portion where the ink is transferred to the intermediate transfer member is quickly transferred from the intermediate transfer member. The heating elements of the thermal head so that can be peeled off is characterized in that formed at the end of the insulating substrate.

[0012]

According to the present invention, the ink ribbon at the portion where the ink is transferred to the intermediate transfer member is quickly removed from the intermediate transfer member, and the intermediate transfer member is heated, so that the resin-based ink is used for heating. Since it can be peeled off,
Good quality printing can be performed by uniformly depositing the ink on the paper having a rough surface.

[0013]

The present invention will be described below with reference to the embodiments shown in the drawings. It should be noted that the same or corresponding configurations as those of the conventional one described above are denoted by the same reference numerals in the drawings, and description thereof will be omitted.

FIGS. 1 and 2 show an embodiment of the thermal transfer printer of the present invention. The thermal head 3 in this embodiment is made of a material such as ceramic as shown in detail in FIG. It has a flat insulating substrate 10. A glaze layer 11 made of a material such as glass and having a heat storage function is laminated on one end of the insulating substrate 10. The upper surface of the glaze layer 11 is formed in an arc shape so that the top portion thereof extends in the alignment direction of the heating elements 4. On the top of the glaze layer 11, a plurality of heating elements 4 are linearly arranged. Further, a common electrode (not shown) and an individual electrode (not shown) for supplying power to the heating element 4 are connected to each heating element 4, and in the present embodiment, the common electrode is provided from the end side of the insulating substrate 10. It is connected to each heating element 4.

The length of the common electrode from the end face 12 of the insulating substrate 10 to each heating element 4 is 0.9 mm or less. This size is extremely smaller than that of the conventional thermal head. As a result, in the thermal head 3 of this embodiment, each heating element 4 is located near the end face 12 of the insulating substrate 10, a so-called real edge. It is said to be of a type.

The thermal head 3 of this embodiment having the above-described structure is arranged so that the end surface 12 of the insulating substrate 10 is located downstream of the heat generating element 4 in the running direction of the ink ribbon 6. Further, on the downstream side of the thermal head 3 in the traveling direction of the ink ribbon 6,
A peeling pinch roller 13 for immediately peeling off the ink ribbon 6 at a portion passing through the heating element 4 from the intermediate transfer roller 1 is rotatably arranged on an extension of the insulating substrate 10 of the thermal head 3 in the longitudinal direction. By moving the ink ribbon 6 along the outer peripheral surface of the pinch roller 13 on the side separated from the intermediate transfer roller 1, the portion of the ink ribbon 6 that has passed through the heating element 4 is immediately separated from the intermediate transfer roller 1. can do.

The other construction is the same as that of the conventional one described above.

Next, the operation of this embodiment having the above-mentioned structure will be described.

In order to perform printing, while the sheet 9 is inserted between the intermediate transfer roller 1 and the pressure roller 8, the intermediate transfer roller 1 is rotationally driven so that the sheet 9 is conveyed and at the winding side. The thermal head 3 is driven based on desired print data while winding the ink ribbon 6 at a predetermined speed by the ribbon roll 7B. As a result, the thermal head 3 generates heat and the ink on the ink ribbon 6 is partially melted, and the intermediate transfer roller 1
Is transferred to the surface of the first recording medium to form a primary recording image.

By the way, the ink of the ink ribbon 6 in this embodiment is of resin type suitable for peeling at the time of heat, while the thermal head 3 in this embodiment is of the real edge type and the pinch roller 13 is used. By this action, the ink ribbon 6 at the portion passing through the heat generating element 4 is immediately separated from the intermediate transfer roller 1, and the intermediate transfer roller 1 is also heated by the heater 2 provided therein. The ink of the ink ribbon 6 in the portion melted by heat is transferred to the intermediate transfer roller 1 while it is still melted. Therefore, the ink of the ink ribbon 6 is transferred to the intermediate transfer roller 1 when it is in a film state due to melting, and the ink of the ink ribbon 6 is evenly attached to the primary recording image on the intermediate transfer roller 1. It is of good quality.

Next, the heater 2 of the intermediate transfer roller 1
While the ink transferred to the intermediate transfer roller 1 is heated so as to be in a semi-molten state by the ink to form a film of ink with a certain degree of viscosity, the pressure of the pressure roller 8 causes the primary transfer of the intermediate transfer roller 1. The recording image is retransferred to the sheet 9 to perform desired printing on the sheet 9. At this time, since the ink of the primary recording image is in a film state, the ink is evenly adhered to the printing on the sheet 9. It can be of good quality. As described above, in this embodiment, since the resin-based ink is used and the transfer is performed when the ink is in the form of a film due to heat, it is possible to always perform good quality printing.

The present invention is not limited to the above-mentioned embodiment, but various modifications can be made if necessary. For example, in the above-described embodiment, the intermediate transfer roller is used as the intermediate transfer body, but it is also possible to use a belt or the like as the intermediate transfer body.

[0023]

As described above, according to the thermal transfer printer of the present invention, the transfer can be performed when the ink is in the form of a film due to heat, so that it is good even for a paper having a rough surface. It is possible to achieve an effect that printing with various qualities can be performed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a thermal transfer printer according to the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a schematic configuration diagram showing a conventional thermal transfer printer.

[Explanation of symbols]

 1 Intermediate Transfer Roller 2 Heater 3 Thermal Head 4 Heating Element 6 Ink Ribbon 8 Pressure Roller 9 Paper 10 Insulating Substrate 11 Glaze Layer 12 End Face of Insulating Substrate 13 Pinch Roller

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location 8906-2C B41J 3/20 113 J

Claims (1)

[Claims] 1. A thermal head having heating elements arranged on an insulating substrate and partially melting ink of an ink ribbon according to print data, and an intermediate transfer member heated by a heating unit. A pressure roller is provided which is in contact with the intermediate transfer body while interposing an ink ribbon, and the thermal head transfers the ink of the ink ribbon to the intermediate transfer body to form a primary recording image. In a thermal transfer printer that transfers a primary recording image of the intermediate transfer member to a sheet inserted between a body and the pressure roller by a pressure contact force of the pressure roller to perform desired printing, ink is transferred to the intermediate transfer member. Each heating element of the thermal head has the insulating property so that the ink ribbon at the transferred portion can be quickly separated from the intermediate transfer member. A thermal transfer printer characterized in that it is formed on the edge of a substrate.