JPS6147273A - Recording method of serial type thermal transfer printer - Google Patents

Abstract

PURPOSE:To obtain a sharp printing pattern excellent in dot reproducibility even if the smoothness of image receiving paper is low and the temp. of a use environment is low and to attain to prolong the pulse life of a heat generator, by sliding a thermal printing head on the same place of the image receiving paper plural times through a transfer film having the same color. CONSTITUTION:At first, a thermal printing head 1 slides over a first one process to perform the printing of one line. By this operation, a first printing pattern Pa is formed to the required place of image receiving paper 3. After the printing operation of the first one process, the thermal printing head 1 performs the same printing operation of the same color to the same place of the image receiving paper 3 in such a state that no paper is fed and the transfer film 2 having the same color as that at the time of previous printing is interposed between the thermal printing head 1 and the image receiving paper 3. By the printing operation of this second process, the printing pattern having the same color is printed on the first printing pattern Pa in a superposed state and, by so called overlapping printing, a sharp printing pattern Pb is formed finally.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a recording method for a serial type thermal transfer printer.

<Prior art> In a serial type thermal transfer printer, a transfer film whose surface is coated with ink is interposed between a thermal print head and image receiving paper, and the thermal print head transfers the image while sliding in a direction across the image receiving paper. By heating the film from the back side, the ink is transferred to the receiving paper that is in close contact with the surface of the transfer film.
A desired pattern is printed on the image receiving paper,
Unlike thermal printers, this type of printer does not require the use of specific paper such as thermal paper, and there are no particular restrictions on the receiving paper that should be used, and plain paper can be used. Currently, various types of plain paper are used in the industry.

<Problems to be Solved by the Invention> By the way, if the image receiving paper used by the user in this type of thermal transfer printer has low smoothness and the surface of the paper is rough, the ink-coated surface of the transfer film and the surface of the image receiving paper may The adhesion was poor, and the ink was not completely transferred to the surface of the image-receiving paper, resulting in poor dot reproducibility and unclear print patterns, resulting in a significant deterioration in print quality.

Mainly, if the temperature of the environment in which this type of printer is used is low, heating the thermal print head alone will not raise the temperature of the printed area on the image receiving paper to the required temperature, so that the temperature of the printed area on the image receiving paper will not rise to the required temperature. The fixability of the ink deteriorates, which may also lead to a decrease in dot reproducibility.

On the other hand, in order to make the print pattern clearer, it is possible to increase the power applied to the heating element of the thermal print head to increase the amount of heat generated by the heating element. If the value becomes large, there arises a disadvantage that the life of the heating element relative to the applied power, the so-called pulse life, becomes short.

The present invention is easy to implement in a serial type thermal transfer printer, and even if the image receiving paper has low smoothness or the temperature of the usage environment is low, it can produce sharp images with excellent dot reproducibility. The purpose of this method is to obtain a printing pattern that is consistent with that of the other hand, and to prolong the pulse life of the heating element.

Means for Solving the Problems> The present invention has been made in view of the above-mentioned problems.In a serial type thermal transfer printer, the thermal print head prints at the same location on the image receiving paper through a transfer film of the same color. The feature is that almost the same pattern can be printed repeatedly by sliding the top a plurality of times.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 is an overall configuration diagram of a serial type thermal transfer printer used for carrying out the present invention. In the figure, reference numeral 1 denotes a serial type thermal print head, 2 a transfer film, and 3 an image receiving paper. Thermal printing heater 1 has heating elements 5 arranged in a row on a substrate 4, and is slid in a direction A across the image receiving paper 3 by a sliding means 6. This causes the relevant parts to generate heat. 8 is a sliding drive unit that energizes the sliding means 6;
9 is a platen, 10 is a motor that rotates the platen 9, 11 is a paper feed drive unit that drives the motor 10, and 12
is a control circuit that controls the printing operation of the thermal printing spatula 1'1 and the paper feeding operation of the platen 9.

In the above configuration, the thermal printing pad 1 heats the transfer film 2 from the back side while sliding in the direction A across the image-receiving paper 3, so that ink is applied to the image-receiving paper 3 that is in close contact with the surface of the transfer film 2. A desired pattern is printed on the image-receiving paper 3. In the present invention, the thermal print head 1 prints the same spot on the image-receiving paper 3 twice or more times in a direction across the image-receiving paper 3. The printing operation is performed by sliding the printer in the direction A, and by performing the printing operation multiple times, substantially the same printing pattern is repeatedly printed to form the required printing pattern for one line.

That is, as shown in the explanatory diagram of FIG. 2(A), the thermal printing head 1 first slides one stroke to print one line.

As a result, the first print pattern Pa is formed at a required location on the image receiving paper 3. This first print pattern Pa usually has low clarity. After the first printing operation, without paper feeding, a transfer film 2 of the same color as the previous printing is placed between the thermal printing pad 1 and the receiver paper 3.
, the thermal printing head 1 performs the same printing operation in the same color on the same location on the image receiver 'IA3.

By the printing operation in this second step, the printing pattern of the same color is printed overlappingly on the first printing pattern Pa as shown in FIG. A pattern Pl) is formed.

The first printing pattern Pa and the printing pattern formed in the second process may be the same, but the printing pattern formed in the second process may compensate for unclear parts of the first printing pattern Pa. , may partially overlap each other.

The printing operation of the thermal print head 1 may be performed three or more times on the same location on the image-receiving paper 3, but the printing operation on the same location should be performed at least twice. In this case, 2
The subsequent printing operations are performed during the forward movement of each stroke, but the second or even-numbered printing operations may be performed during the backward movement using the backward movement of the first stroke or each subsequent stroke.

Furthermore, normally, overlapping printing is always performed two or more times as described above, but printing conditions such as whether or not to perform overlapping printing and how many times overlapping printing is to be performed can be changed automatically or by the user's operation. You can do it like this. When automatically switching printing conditions, a means for detecting the smoothness of the image receiving paper 3 or a means for detecting the reflectance of the printed portion of the image receiving paper 3 is provided, and printing is performed according to a detection signal from the detecting means. Switch conditions.

<Effects of the Invention> As described above, according to the present invention, almost the same printing pattern in the same color is repeatedly printed multiple times at required locations on the image-receiving paper. Even when the temperature of the usage environment is low, a clear print pattern with good dot reproducibility can be obtained by overlapping printing, and the print quality can be maintained at a high level.

Moreover, compared to the conventional method of forming a print pattern of the required density in a single printing operation, less power is applied to the heating element of the thermal print head during each printing operation.
It reduces the burden on the heating element and extends the pulse life of the thermal print head, and it slides over the area multiple times, adding a new mechanical structure to existing serial type thermal transfer printers. Therefore, it can be easily implemented using an existing printer of this type.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a serial type thermal transfer printer used for carrying out the present invention, and FIGS. 2(A) and 2(B) are explanatory diagrams showing the state of printing by the method of the present invention. 1...Thermal print head, 2...Transfer film, 3...
・Receiving paper, Pa...first printing pattern, pb...
Final print pattern.

Claims (1)

[Claims] (1) A recording method for a serial thermal transfer printer in which a transfer film is interposed between a thermal print head and an image receiving paper, and the thermal print head prints by sliding in a direction across the image receiving paper,
A recording method for a serial type thermal transfer printer, characterized in that substantially the same pattern is repeatedly printed by a thermal print head sliding over the same location on an image receiving paper multiple times via a transfer film of the same color.