JP2905003B2 - Thermal transfer printer - Google Patents

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 printing by transferring ink on an ink ribbon to paper by the heat of a thermal head, and in particular, transferring the ink on an ink ribbon to an intermediate transfer member by a 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 paper and performs desired printing.

[0002]

2. Description of the Related Art Conventionally, a thermal transfer printer which performs printing in a state where a thermal head is pressed against a platen via a sheet and an ink ribbon is often used. When printing on 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, a primary recording image is formed on the intermediate transfer body by partially melting the ink of the ink ribbon by the heat generated by the thermal head and transferring the ink to the intermediate transfer body. 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 member against the sheet with a pressing force.

FIG. 2 schematically shows such a conventional intermediate transfer type thermal transfer printer.
A cylindrical intermediate transfer roller 1 constituting an intermediate transfer member is rotatably disposed. Inside the intermediate transfer roller 1, a heater 2 for heating the intermediate transfer roller 1 to a predetermined temperature is provided. Built-in. In the vicinity of the intermediate transfer roller 1, a thermal head 3 is provided. The thermal head 3 has a plurality of heating elements 4 arranged in a straight line and arranged so as to face the center of the intermediate transfer roller 1. On both sides of the thermal head 3, ink is applied to a bobbin 5. A pair of ribbon rolls 7 for winding the ribbon 6 and guiding the ink ribbon 6 substantially linearly between the intermediate transfer roller 1 and the thermal head 3
A and 7B are provided. Of these, ribbon roll 7
A is on the supply side, and the ribbon roll 7B is on the winding side.

[0004] A pressure roller 8 pressed against the intermediate transfer roller 1 with a strong pressing force is rotatably disposed at a position diametrically symmetric with respect to the thermal head 3 of the intermediate transfer roller 1. A predetermined sheet 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 driven to rotate. The ink ribbon 6 is conveyed in a direction opposite to the running direction of the ink ribbon 6 while being sandwiched between the pressure rollers 8.

Further, the ink ribbon 6 used for the printing is formed by, for example, laminating an ink obtained by mixing a colorant with a wax-based component on a surface of a base film made of a resin.

According to the above-described conventional thermal transfer printer,
A sheet 9 between the intermediate transfer roller 1 and the pressure roller 8
Is inserted, the pressure roller 8 is pressed against the intermediate transfer roller 1 with a strong pressing force, and the thermal head 3 is pressed against the intermediate transfer roller 1. In this state, the intermediate transfer roller 1 is driven to rotate, and 9 and the ribbon roll 7 on the winding side.
While the ink ribbon 6 is wound at a predetermined speed by B, the thermal head 3 is driven based on a desired print signal. As a result, the thermal head 3 generates heat and the ink on the ink ribbon 6 is partially melted.
Is transferred to the surface of the recording medium to form a primary recording image. At this time,
Since the primary recording image formed on the surface of the intermediate transfer roller 1 only needs to be held on the intermediate transfer roller 1, it is not necessary to press the thermal head 3 against the intermediate transfer roller 1 with a very strong pressure.

The heater 2 of the intermediate transfer roller 1
In a state in which the ink transferred to the intermediate transfer roller 1 is heated to a certain temperature to cause the ink to have some viscosity, the pressure contact force of the pressure roller 8
The primary print image of the intermediate transfer roller 1 can be re-transferred to the paper 9 to perform desired printing on the paper 9. This allows
Since the image is re-transferred onto the paper 9 by the pressure roller 8 with a strong pressing force, printing can be performed even on paper 9 having a rough surface such as bond paper.

[0008]

By the way, in the above-mentioned conventional printer, as described above, the ink ribbon 6 having the wax-based ink is used. Since the melting point is relatively low, the temperature setting range for heating the primary transfer image by the heater 2 is narrow, and it is difficult to control the temperature.
Further, since the wax-based ink is an aggregate of particles even in a semi-molten state, when the intermediate transfer roller 1 is re-transferred to the paper 9, a part of the ink is transferred to the intermediate transfer roller 1.
Paper 9
There was a possibility that a problem might occur in the final print quality.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a thermal transfer printer capable of performing good quality printing in an intermediate transfer system.

[0010]

According to a first aspect of the present invention, there is provided a thermal transfer printer, wherein an ink ribbon is provided between a thermal head having a heating element formed on a substrate and an intermediate transfer member. And a pressure roller that is pressed against the intermediate transfer body is provided, and the ink on the ink ribbon is transferred to the intermediate transfer body by the thermal head to form a primary recording image, and the intermediate transfer body and the intermediate transfer body are formed. In a thermal transfer printer for performing a desired printing by transferring a primary recording image of the intermediate transfer body to a sheet inserted between the pressure roller and a pressure contact force of the pressure roller, the ink of the ink ribbon is made of a resin material. The heating element of the thermal head is formed substantially at the edge of the substrate in order to separate the ink from the intermediate transfer body when the ink is in a molten state. And, in the roller the intermediate transfer member
And forming Ri, on the intermediate transfer body, the primary recording image on the intermediate transfer member is disposed a heating means for heating to a temperature below the melting temperature of the high and the ink from ambient temperature, the intermediate
Make the outer diameter of the transfer member smaller than the design size at room temperature.
It is characterized in that was.

[0011]

[0012]

According to the present invention, the primary recording image formed of the resin-based ink formed on the intermediate transfer member is heated to a temperature higher than the ambient temperature and lower than the melting temperature of the ink by the heating means. The retransfer of the primary recorded image from the transfer body to the paper can be performed when the ink is in a semi-molten state and is in the form of a film. Therefore, the primary recording image is completely transferred to the sheet, and printing of good quality can be performed. In particular, the intermediate transfer member is formed by a roller.
And the primary transfer on the intermediate transfer body
The recorded image is higher than the ambient temperature and lower than the melting temperature of the ink
A heating means for heating the intermediate transfer member to a high temperature.
Since the outer diameter is smaller than the design size at room temperature,
Relative speed between ink ribbon and paper
Can be absorbed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings. Note that the same or corresponding components as those of the above-described conventional device are denoted by the same reference numerals in the drawings, and description thereof will be omitted.

FIG. 1 shows an embodiment of a thermal transfer printer according to the present invention. In a thermal transfer printer according to the present invention, a thermal head 3 includes a heating element 4 formed on a substrate 10 and arranged in a line. Of the so-called real edge type formed substantially at the edge. That is, a common electrode (not shown) and an individual electrode (not shown) are respectively connected to both sides of each heating element 4 in order to energize each heating element 4, of which the width of the common electrode located on the edge side of the substrate 10 is However, in this embodiment,
Each heating element 4 is located within a range of 0.9 mm or less from the edge of the substrate 10.

The edge of the substrate 10 where the heating element 4 is located is opposed to the ribbon roll 7B on the winding side.
Further, the thermal head 3 is movably arranged so that each heating element 4 can come into contact with and separate from the intermediate transfer roller 1. Further, the traveling direction of the ink ribbon 6 is set between the thermal head 3 and the ribbon roll 7B on the take-up side so that the ink ribbon 6 passing through the heating element 4 is immediately separated from the intermediate transfer roller 1. A pinch roller 11 is provided to regulate the transfer roller 1 outward from the tangential direction so that the ink on the ink ribbon 6 is transferred to the intermediate transfer roller 1 when the ink is in a molten state.

The ink ribbon 6 is formed by laminating an ink obtained by mixing a resin component with a colorant on the surface of a base film made of a material such as polyethylene terephthalate.

A heater 2 as a heating means is provided in the intermediate transfer roller 1, and the heater 2 is for preheating the primary recording image transferred on the intermediate transfer roller 1. . The heater 2 heats the surface of the intermediate transfer roller 1, that is, the primary recording image, to a temperature higher than the ambient temperature and lower than the melting temperature of the ink, in this embodiment, about 50 ° C. to 63 ° C. Has become.

Since the diameter of the intermediate transfer roller 1 is increased by being heated by the built-in heater 2, the peripheral speed of the intermediate transfer roller 1 becomes faster than the design size at normal temperature, and the ink ribbon 6 and the paper 9 will have a relative speed. If this is left as it is, the final print on the paper 9 may be distorted. Therefore, in the present embodiment, the relative speed generated between the ink ribbon 6 and the paper 9 is absorbed by forming the outer diameter of the intermediate transfer roll 1 to be smaller than the design dimension at normal temperature.

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

In order to perform printing, with the paper 9 inserted between the intermediate transfer roller 1 and the pressure roller 8, the pressure roller 8 is pressed against the intermediate transfer roller 1 with a strong pressing force, and the thermal head 3 is pressed. Heater 2
Is pressed against the intermediate transfer roller 1 heated to a predetermined temperature, and in this state, the intermediate transfer roller 1 is driven to rotate to convey the paper 9 and to take up the ink ribbon 6 by the take-up ribbon roll 7B. While winding at a predetermined speed, the thermal head 3 is driven based on a desired print signal. As a result, the thermal head 3 generates heat and the ink on the ink ribbon 6 is partially melted and adhered to the surface of the intermediate transfer roller 1. Therefore, when the ink is in this molten state, the pinch roller 11 rotates the intermediate transfer roller. Peel ink ribbon 6 from 1 (peeling when heated)
Then, the ink on the ink ribbon 6 is partially transferred to the intermediate transfer roller 1 to form a primary recording image on the intermediate transfer roller 1. At this time, the primary recording image formed on the surface of the intermediate transfer roller 1 only needs to be held on the intermediate transfer roller 1, so that the thermal head 3 does not need to be pressed against the intermediate transfer roller 1 with a very strong pressure.

The ink of the primary recording image transferred to the intermediate transfer roller 1 is heated by the heater 2 in the intermediate transfer roller 1 to a set temperature equal to or lower than the melting point, and the ink is turned into a semi-molten state having a certain degree of viscosity. The primary recording image of the intermediate transfer roller 1 is re-transferred to the paper 9 by the pressure contact force of the pressure roller 8, and desired printing can be performed on the paper 9. When the primary recording image is re-transferred from the intermediate transfer roller 1 to the paper 9, the ink forming the primary recording image is in the form of a film. Is completely re-transcribed,
In addition, since the paper is re-transferred to the paper 9 by the pressure roller 8 with a strong pressing force, the paper 9 having a rough surface
, It is possible to perform good quality printing.

According to this embodiment, the so-called real edge type thermal head 3 and the ink ribbon 6 made of resin-based ink are used, and the diameter of the intermediate transfer roller 1 is set in consideration of expansion by heat. The primary recorded image on the intermediate transfer roller 1 is re-transferred to the paper 9 in a semi-molten state by the heater 2 of the above, so that printing of good quality can be performed on the paper 9 such as bond paper having a rough surface. It can be performed.

The image is retransferred to the paper 9 and finally a printed matter (paper 9) can be obtained.

The present invention is not limited to the above embodiment, but can be variously modified as needed.

[0025]

As described above, the thermal transfer printer according to the present invention has an effect that good quality printing can be performed even on paper having a rough surface. In particular, the intermediate transfer member is formed by a roller and
Then, the primary recorded image on the intermediate transfer member is stored in the intermediate transfer member.
Temperature higher than ambient temperature and lower than ink melting temperature
A heating means for heating is provided, and the outer diameter of the intermediate transfer body is kept constant.
Since the diameter is smaller than the design size at the temperature,
Absorbs the relative velocity generated between the paper and paper
In this respect, good quality printing can be performed.
I can.

[Brief description of the drawings]

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

FIG. 2 is a schematic configuration diagram showing a conventional intermediate transfer type thermal transfer printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intermediate transfer roller 2 Heater 3 Thermal head 4 Heating element 6 Ink ribbon 7A, 7B Ribbon roll 8 Pressure roller 9 Paper 10 Substrate 11 Pinch roller

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/32-2/325

Claims (1)

(57) [Claims] An ink ribbon is interposed between a thermal head having a heating element formed on a substrate and an intermediate transfer member,
A pressure roller that is pressed against the intermediate transfer body is provided, and the ink on the ink ribbon is transferred to the intermediate transfer body by the thermal head to form a primary recording image, and a gap between the intermediate transfer body and the pressure roller is formed. In a thermal transfer printer for performing a desired printing by transferring a primary recording image of the intermediate transfer body to a sheet inserted by a pressure contact force of the pressure roller, the ink of the ink ribbon is formed of a resin-based material. ink heating elements of the thermal head is formed substantially in the edge of the substrate to be peeled off from the intermediate transfer member when in the molten state, the intermediate
The transfer body is formed by rollers, and this intermediate transfer
The body, the primary recording image on the intermediate transfer member is disposed a heating means for heating to a temperature below the melting temperature of the high and the ink from ambient temperature, set the outer diameter at room temperature of the intermediate transfer body
A thermal transfer printer characterized in that the diameter is smaller than the total size .