JPS6347168A - Printer - Google Patents

Abstract

PURPOSE:To prevent disturbance of a print image due to a temperature disturbance, by providing a mechanism for heating a means which peels pressure transferred ink from a transfer paper, an ambient temperature detecting means and a control mechanism for varying the temperature of the heating mechanism based on a signal being fed from the temperature detecting means. CONSTITUTION:An ink layer 11 is fused by means of a recording head 21 and adhered to a transfer paper 12. Then an electric heat transfer recording film 13 is peeled from the transfer paper 12 at a peeling roller section 108 to leave only such ink 301 as adhered to the transfer paper 12 thus producing an image. A control section 102 detects the temperature of a temperature detecting means 157 and sets the output from a variable power source 103, then voltage is applied between electrical contacts 212, 213 to heat the peeling roller 108 so as to maintain the temperature of the peeling roller 108 at such level as being preset through a feedback loop. The temperature is set to be higher than the highest temperature predictable through consideration of environmental temperature, accumulation of heat of recording head, etc. but lower than the active temperature of the ink.

Description

[Detailed description of the invention] [Industrial application fields] 11 The present invention relates to a printing apparatus using a thermal transfer recording method.

[Prior art] As a printing device using the conventional electrical thermal transfer recording method,
There was a printing device J (patent application 186496/1986).

In this method, as shown in FIG. 5, the heat-melting ink 11 is applied to one side of a film-like substrate 10, and the electrically conductive thermal transfer film 13 having the resistance layer 14 on the other side is attached to the resistance layer 1.
a recording head 2 having a recording electrode 20 for passing current through the recording head 2;
1, the ink 11 is selectively heated to melt the ink 11, and an image is obtained by applying a pressure transfer film to the transfer paper 12.

It had features such as silent printing, the use of pigment-based inks, high-density printing, easy color printing, easy line-up of the recording head, and high-speed printing.

[Problems to be Solved by the Invention] However, in the conventional example described above, the melting area of the ink changes depending on the temperature, so the area of the transfer dot changes due to changes in the environmental temperature or heat accumulation in the recording head during printing. This has caused a problem in that the density of the printed image changes. In addition, there is a means to correct the print data by detecting the change in the environmental temperature to solve the above problem, but since the correction means is performed on a large amount of print data, the processing becomes complicated and the mechanism associated with it becomes complicated. This was one of the reasons for the price increase.

SUMMARY OF THE INVENTION The present invention is intended to solve these problems, and its purpose is to provide a high-quality electrically conductive thermal transfer recording device in which printing is not disturbed by thermal disturbances.

Means for Solving Problem E] The printing apparatus of the present invention includes a mechanism for heating a means for separating pressure-transferred ink and transfer paper, a temperature detecting means near the heating mechanism, and a temperature detecting means for the heating mechanism. [Embodiment] Fig. 1 is a diagram showing the configuration of an electric thermal transfer printing apparatus according to the present invention, characterized in that it is constituted by a control mechanism that can change the temperature of the heating mechanism in response to a signal from a detection means. . Reference numeral 21 denotes a recording head, which is made of a nonflammable insulator, and has a plurality of recording heads 20 arranged in parallel on a support 200. 1 is a recording power source.

In the present invention, recording is obtained by applying a voltage between the recording electrodes, and the positive and negative electrodes of the recording power source 1 are alternately connected to the recording electrodes. Reference numeral 13 denotes an electrically conductive thermal transfer film, which includes a resistance layer 14, a support layer 10, and an ink layer 11. 12 is a transfer paper. 210 is a support for supporting the transfer paper. Reference numeral 100 denotes a peeling roller which is a mechanism for peeling off the energized thermal transfer film 13 and the transfer paper 12 after transfer, and also serves as an electric resistance heater. It's being held in place. Peeling roller 100 has electrical contacts 212.2
13 to the variable power supply 103, respectively. 1
57 is a temperature detection means, which uses a thermistor and connects to temperature contact 2.
14, the temperature of the peeling roller 100 is detected.

102 is a control section of the variable power supply 103.

During printing, while the electrically conductive thermal transfer film 13 and the transfer paper 12 are conveyed in the direction of arrow A, the recording head 21 applies a current to the resistance layer 14, and the heat generated melts the ink layer 11 and transfers the transfer paper 12 as shown at 300. Glue to.

Thereafter, the electrically conductive thermal transfer film 13 is peeled off from the transfer paper 12 by the peeling roller 1oO, and only the ink 301 adhered to the transfer paper 12 remains on the transfer paper 12 to obtain an image.

The control unit 102 detects the temperature of the temperature detection means 157, sets the output of the variable type N103, and applies voltage between the electrical contacts 212 and 213, causing the peeling roller 100 to generate heat. The temperature of the peeling roller 100 is kept constant at a preset temperature by the feedback loop described above. The set temperature was set to be higher than the maximum temperature that can be predicted and lower than the activation temperature of the ink, taking into account environmental temperature, heat accumulation in the recording head, and the like. In this example, the melting point of the ink was about 60°C, and the set temperature was 50°C.

FIG. 2 shows a schematic perspective view of the peeling roller 100 and its peripheral elements. The peeling roller 100 has a hard roller shaft 21
5 and an elastic section 216. The material of the roller shaft 215 is structural carbon steel, and an insulating film (not shown) is formed on its surface by oxidation treatment. The elastic portion 216 is made of NBR rubber mixed with carbon to provide electrical resistance. The elastic part 2
16 is hollow-molded and the roller shaft 215 is press-fitted to form the peeling roller 1.
00 was formed. The resistance between the ends of the peeling roller 100 is approximately 1
It was 0Ω.

The electrical contacts 212 and 213 formed from pieces of copper foil are pressed into contact with both ends of the peeling roller 100, and the variable power source 103
is connected to. The temperature contact point 214 was similarly formed from a piece of copper foil, and the thermistor 157 was fixed onto the temperature contact point 214 with an adhesive having good thermal conductivity. Variable power supply is 10±5■
The peeling roller 100 has a median value of 10.
Enables W to generate heat.

FIG. 3(a) shows the structure of an energized thermal transfer film roll of a printing apparatus according to the present invention. 73 is an electrically conductive thermal transfer film having a roll of approximately 20 m.

Yellow (Y) and magenta (M) for color printing
, cyan (C) ink is sequentially applied to an area corresponding to the screen.

FIG. 3, (b) is a sectional view of the electrically conductive thermal transfer film. The electric thermal transfer film has a base 82 of PET with a thickness of 6 μm, and on one side a resistive layer 81 consisting of carbon grains dispersed in resin and coated to a thickness of 4 to 6 μm, and on the other hand, as a layer 83 on the ink, a pigment is coated in wax. The material was dispersed in the following materials and coated to a thickness of 2 to 3 μm.

FIG. 4 is a structural diagram of a recording head in an embodiment of the present invention. The recording head includes a recording section 92 and a drive C mounting section 84.
, a connecting portion 93 that electrically connects the recording portion 92 and the drive unit C mounting portion 94.

The drive IC 95 is a C-based version of the drive circuit according to the present invention, and includes 40 drive elements per chip. Eleven drive units C95 were mounted on the mounting section 94.

The recording section 92 is composed of a recording electrode 97, a support 91 for the recording electrode, and an insulating film 96 on the recording electrode.

The support 91 was made of machinable ceramics mainly composed of mica, and the recording electrode 97 was made of tungsten.

The recording electrode 96 is bonded onto the support 91 with an inorganic adhesive and then 1. After etching and patterning with butic acid, the recording conductor was coated 96 with a heat-resistant coating material that was relatively softer than the recording conductor. The array spacing is 170 μm (6
(equivalent to dot/mm).

FIG. 5 shows a basic block diagram of the signal system of the printing apparatus according to the present invention. A control circuit 45 supplies a reference signal to each block. The video signal input from 41 extracts a horizontal synchronizing signal and a vertical synchronizing signal 43 by a sampling circuit 42 and sends them to a control circuit 45. The control circuit 45 calculates a sampling signal 44 from the received synchronization signal 43 and sends it to the sampling circuit 42. The sampling circuit 42 samples the video signal using this sampling signal, and separates the color signal and luminance signal into RGB signals.
Convert to signal. This RGB signal 50 is converted into a 6-bit digital signal 51 for each color by an A/D conversion circuit 59, and further subjected to color correction by a gamma correction circuit 52, and printing data signals 53 for yellow, magenta, and cyan.
and is temporarily stored in the memory in the print data generation circuit 54. The print data generation circuit 54 modulates the 6-bit print data into the time period for which current is applied to the resistive layer. For example, if the 6-bit density data of 11 strokes is d (0≦d
≦63), τxd for the minimum energization time unit τ
generate. However, the maximum energization time for one pixel is 63×τ. The printing data is transferred to a shift register 55 having 88 serial inputs and parallel outputs. 46 is a transfer lock of the shift register 55. The printing data 60 output in parallel is held by 57 latches using 47 latch clocks, and further transferred to 30 data select circuits. In this embodiment, 115 time division drives are performed. The reason for performing this time division is to avoid crosstalk of currents on the resistance layer of the energized thermal transfer film due to simultaneous energization. Therefore, the aforementioned data select circuit 3
At 0, the transferred parallel printing data 61 is distributed to each drive element 21 by the 3-bit select I/address signal 48 from the control circuit 45.

When printing was attempted with the printing apparatus having the above configuration using various environmental temperatures and various printing patterns, the printing density was constant under all conditions, and stable image quality was obtained.

In addition, since the area near the recording area is preheated to a temperature relatively higher than room temperature, printing efficiency is improved, the current load on the recording electrode of the recording head is reduced, and durability deterioration such as wear of the recording electrode due to long-term printing is reduced compared to conventional methods. Furthermore, the transfer paper 12 was warmed by the heating and became more compatible with the melted ink 300, improving transferability and eliminating transfer defects such as dots.

[Effects of the Invention] As described above, according to the present invention, there are provided a mechanism for heating the means for separating the pressure-transferred ink and the transfer paper, a temperature detecting means near the heating mechanism, and the temperature detecting means. If the printing device is configured with a control mechanism that can change the temperature of the heating mechanism based on a signal from the printer, this relatively simple mechanism will prevent fluctuations in print density due to temperature disturbances such as environmental temperature fluctuations and heat accumulation in the recording head. It is effective for In particular, the present invention is particularly effective in the gradation printing apparatus described in this embodiment, since image quality is impaired by subtle changes in density.

In addition, since the area near the recording area is heated in advance to a temperature relatively higher than room temperature, printing efficiency is improved and the current load on the recording electrode of the recording head is reduced, which prevents durability deterioration such as wear of the recording electrode due to long-term printing. In addition to being effective, the load on the drive circuit of the recording head is also reduced, which eases the restrictions on specifications and is effective in reducing costs.

Furthermore, the transfer paper is warmed by the residual heat and becomes more compatible with the molten ink, improving transferability, eliminating transfer defects such as dots, and improving image quality.

Furthermore, since there is no problem such as heat accumulation in the recording head, high-speed printing is possible.

As described above, the present invention is effective not only in stabilizing the image quality but also in reducing the cost of the device and improving the image quality.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a printing apparatus according to the present invention. FIG. 2 is a diagram showing the structure of the heating mechanism according to the present invention. FIGS. 3(a) and 3(b) are diagrams showing the structure of the electrically conductive thermal transfer film according to the present invention. FIG. 4 is a diagram showing the structure of a recording head according to the present invention. FIG. 5 is a diagram illustrating a signal processing system according to the present invention. FIG. 6 is a diagram illustrating a conventional electrical thermal transfer recording method. 1...Recording power supply 10...Support layer 11...Ink layer 12...Transfer paper 13...Electrifying thermal transfer film 20...Recording electrode 21...Recording Head 157...Temperature detection means 100...Peeling roller 212...Electric contact 213...Electrical contact 214...Temperature contact and above Figure 2 73(α) (b) Third Figure'// Figure 4 Ichimori No. 3 (+3.At!N stem 74 Lum 3

Claims (1)

[Claims] (1) An electrically conductive thermal transfer film having an ink layer and a resistive layer that can be activated by thermal stimulation and selectively transferred to the printing object under pressure, and the ink is selectively heated and the activated ink is applied with pressure. In a printing device having a means for transferring and a means for peeling off the pressure-transferred ink and the transfer paper,
A mark comprising: a mechanism for heating the peeling means; a temperature detection means near the heating mechanism; and a control mechanism capable of changing the temperature of the heating mechanism based on a signal from the temperature detection means. Photography device.