JPS6163460A - Thermal transfer recording apparatus - Google Patents

Abstract

PURPOSE:To make it possible to obtain the same image quality even if any paper is used as transfer paper, by preheating transfer paper or an ink donor film prior to performing thermal transfer. CONSTITUTION:In this side reaching the thermal head 7 provided to the feed path of recording paper 2, a thermal transfer recording apparatus provided with a preheating apparatus, which consists of a hot roller 4 equipped with a rod heater 3 at the central part thereof and rotating to the A-direction and a pressure roller 4 rotating to the B-direction, is used. The contact nip pressure between the hot roller 4 and the pressure roller 5 is set, for example, to 6mm and an ink donor film coated with ink with m.p. of 70 deg.C is used and the surface temp. of the hot roller 4 is set to 64 deg.C while four kinds of recording papers are used and a heat pulse is applied to said recording papers, after passed between both rollers, by the thermal head of a zerox 6 to perform recording.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention involves placing a transfer paper and an ink donor film coated with hot-melt ink on top of each other, heating the ink donor film in contact with a thermal head, etc. The present invention relates to a thermal transfer recording device that performs recording by transferring ink to transfer paper according to information.

[Conventional technology]

Non-impact type recording devices, such as thermal recording devices, have the advantage that they generate less noise than impact type recording devices, and do not worsen the office environment. Among these, transfer-type thermal recording devices use a thermal transfer recording medium (ink donor film) in which an ink layer that can be transferred by heat is formed on a base material, and an ink image is transferred to a transfer paper by applying a heat pulse. Therefore, compared to conventional recording devices that use heat-sensitive color transfer paper, (1) plain paper can be used as the transfer paper, and (2) the ink layer can be heated to Since it is a mixture of pigments or dyes with a binder agent such as wax that fluidizes or sublimates, the ink image not only has excellent clarity and fastness, but also has the advantage that the recorded color can be freely controlled by selecting the pigment etc. be.

Thermal transfer recording medium has the overall form of carbon paper or carbon ribbon, and thin paper with excellent heat resistance and smoothness has been used as the base material. Conventionally, paper with a highly smooth surface has been generally used as transfer paper, and it has been a well-known fact that the quality of the transferred image varies greatly depending on the surface condition of the transfer paper.

That is, the thermal transfer recording medium as a whole has the form of carbon paper or carbon ribbon, and thin paper with excellent heat resistance and smoothness has been used as the base material. In conventional transfer-type thermal recording devices, a roll-shaped thermal transfer recording medium is installed in the device in order to continuously supply the thermal transfer recording medium to the recording location. . In such a transfer-type thermal recording device, the thermal transfer recording medium is exposed to high temperature and high humidity.
1. If left for a long time, the base material absorbs moisture and expands, and this expansion occurs significantly in the part of the thermal transfer recording medium that is transferred from the supply roll to the recording section in the thermal recording device. did. The extent of this expansion is due to the fact that the part that is drawn out from the supply roll and in contact with the atmosphere absorbs a large amount of moisture.
Because it expands freely, it is large, and the portions that are in pressure contact with components such as rollers for conveying the thermal transfer recording medium are small and uneven because the expansion action in the surface direction is hindered. If the thermal transfer recording medium expands unevenly in this way, undulations may occur on the thermal transfer recording medium in areas where the expansion change is significant, and the wavy areas are heated by the thermal head in the recording section. If wrinkles occur in the thermal transfer recording medium, the ink may not be transferred properly to the transfer paper in the recording section, resulting in omissions or chips in the ink image. This not only degrades the quality of the recording section but also has the disadvantage that necessary image information may not be reproduced (Japanese Unexamined Patent Application Publication No. 1983-1999).
No. 1731953, 58-1it) No. 291).

[Problem that the invention seeks to solve]

The present invention solves the problem that conventionally used transfer paper has poor surface condition due to wrinkles etc. in thermal transfer recording, resulting in large fluctuations in image quality. It is an object of the present invention to provide a thermal transfer writing device that can obtain the same image quality.

[Means and effects for solving problems] Japanese Patent Application Laid-Open No. 1973-
No. 26548 describes a method for printing on thermal paper in which the thermal paper is preheated in advance to increase the sensitivity, but in the thermal transfer recording of the present invention, it is not possible to increase the sensitivity by preheating. do not have. The present inventor has found that by preheating the transfer paper or ink donor film before thermal transfer using a thermal head, etc., the reproducibility of fine lines, solid black and white properties, and fixing properties are particularly improved for any type of transfer paper. The above-mentioned problems have been solved. That is, in the present invention, both sheets of transfer paper and an ink donor film coated with thermoplastic ink are conveyed and overlapped, and a thermal head is pressed against them using a back roller. A device that performs recording by melting ink using thermal energy selectively supplied to transfer an image onto a transfer paper, and is equipped with a device that preheats one of the sheets before it is conveyed to a thermal head section. It is characterized by the presence of

Examples of the preheating device include an open heater, a hot plate, a flash heater, a hot roll, etc., but the heating device is not limited to these examples, and the purpose can be achieved by any commonly used heating device. However, if the heating temperature exceeds the melting point of the recording material for thermal transfer of the ink donor film, the recording material will become fluid, so the preheating conditions must be 40°C or higher and the melting point of the recording material for thermal transfer minus 5 degrees. It is preferable to carry out the reaction at a temperature of 0 or less. When preheating the transfer paper, it is preferable to heat the side of the transfer paper that is in contact with the ink donor film (transfer surface), and when preheating the ink donor film, it is preferable to heat the ink coated side of the transfer paper. Heating is preferred.

When recording is performed using the apparatus of the present invention, the reproducibility of fine lines and the uniformity of solid black are greatly improved, and the degree of fixation after recording is also improved. Furthermore, good image quality can be obtained on any type of transfer paper without having to select the transfer paper (subject to be transferred).

〔Example〕

The present invention will be described in detail below with reference to Examples and Comparative Examples.

Embodiment 1 As shown in FIG. 1 as a schematic diagram of the entire apparatus and as shown in FIG. 2 as a sectional view of the preheating device, a rod-shaped heater 3 is placed at the center of the recording paper 2 transport path before reaching the multi-head 7. A prepared for the department
Using an FI & thermal transfer recording device equipped with a preheating device consisting of a heat roller 4 that rotates in this direction (on the side of the transfer surface of the recording paper and a pressure roller 5 that rotates in the B direction), the heat roller 4 is The contact nip pressure between the pressure roller 5 and the pressure roller 5 is set to 6, and the melting point is 7.
Using an ink donor film coated with ink at 0°C, the surface temperature of the heated roller was set to 64°C, and 4°C was used as recording paper.
Types of paper (Fuji Xerox 2 paper, Fuji Xerox L paper, high-quality printing paper (Tsubo fli 64 f/d, Sarashi Tsuki), after passing between both rolls 4 and 5, heat pulses are applied by Xerox P6 by thermal head 7. was applied and recorded.

Embodiment 2 As shown in FIG. 3, a thermal transfer recording device was used in which an incandescent filament lamp 11 for heating the transfer surface of the recording paper was provided in the recording paper conveyance path leading to the long-maru head.
Using an ink donor film with an ink melting point of 63°C, recording was performed on four types of paper as in Example 1, with the recording paper surface temperature of the portion closest to the incandescent filament being 40°C.

Embodiment 3 A heating plate 1 that heats the transferred surface of recording paper as shown in the meridional diagram.
Ink melting point 6 using a thermal transfer recording device equipped with 2
Using an ink donor film at 6°C, the surface temperature of the hot plate 12 was set to 55° for the same four types of paper as in Example 1.
Recorded as C.

Example 4 As shown in FIG. 5, the heat roller 4 and pressure roller 5 used in Example 1 were placed upside down before reaching the thermal head on the conveyance path of the ink donor film. Using an ink donor film 8 with an ink melting point of 70° C., the surface temperature of the heat roller was set to 64° C. using a thermal transfer recording device arranged to heat the ink-applied side of the film.
As C (the contact nip pressure between the heat roller 4 and the pressure roller 5 was 6 rhymes), recording was performed on the same four types of paper as in Example 1.

Example 5 As shown in FIG. Recording was performed on four types of paper in the same manner as in Example 1, using an ink donor film at 40° C. and setting the surface temperature of the ink donor film at 40° C. when passing directly under the lamp 11.

Example 6 As shown in FIG. 7, an ink donor film having an ink melting point of 66° C. was used to heat the ink coating on the ink donor film using a thermal transfer recording device equipped with a hot plate 12 for heating the ink coating pattern on the ink donor film. Recording was carried out using the same four types of paper as in Example 1, with the surface temperature set at 55°C.

Comparative Example 1 Recording was performed on the same four types of paper as in Example 1 using a Fuji Xerox P6 machine without a preheating device and an ink donor film for P6.

Regarding Examples 1 to 6 and Comparative Example 1, solid black uniformity,
Table 1 shows the results of evaluating fine line reproducibility, degree of fixation, and recording density.

Table 1 ◎: Very good ○: Good Δ: Usable X: Not usable *1 The reproducibility of fine lines was determined by printing 8-point kanji characters and determining the reproducibility of each line of each character.

[Effect of generation + p1] In the present invention, after preheating either the transfer paper or the ink donor film, the ink is melted by thermal energy supplied in accordance with the image information from the thermal head and transferred to the recording paper. According to this apparatus, the reproducibility of fine lines and the uniformity of solid black in recorded images are greatly improved, and the degree of fixation after distribution is also improved. Further, good image quality can be obtained with any type of gI transfer paper.

[Brief explanation of the drawing]

Figure at is a schematic diagram of an embodiment of the present invention equipped with a preheating device for recording paper consisting of a heating roller and a pressure roller, FIG. 2 is a cross-sectional view of the preheating device portion, and FIG. FIG. 4 is a schematic diagram of an embodiment of the invention equipped with an incandescent filament lamp as a preheating device for recording paper; FIG. 5 is a schematic diagram of an embodiment of the invention equipped with a hot plate as a preheating device for recording paper FIGS. 6 and 7 are each a schematic diagram of an embodiment of the present invention with an ink donor film preheating device. Symbols in the figure: 1... Recording paper tray: 2... Transfer paper: 3... Rod-shaped heater; 4... Heat roller; 5... Pressure roller; 6...
... Pressure roller; 7... Thermal head; 8... Ink donor film; 9... Donor film supply roller; 10... Donor film take-up roller; 11...
Incandescent filament lamp; 12...hot plate. Figure 1 3tgJ

Claims (1)

[Scope of Claims] 1. Transfer paper and an ink donor film coated with hot-melt ink are conveyed and overlapped, and are pressed against a thermal head using a back roller. A device that performs recording by melting ink using selectively supplied thermal energy to transfer an image onto transfer paper, and is equipped with a device that preheats one of the sheets before it is conveyed to the thermal head section. A thermal transfer recording device characterized by: 2. The apparatus according to claim 1, wherein the sheet to be preheated is a transfer paper. 3. The apparatus according to claim 1, wherein the sheet to be preheated is an ink donor film.