JPH04269561A - Thermal printing method - Google Patents

Abstract

PURPOSE:To enable specific transfer to be performed at an optional printing start position by a method wherein a counter is operated only during printing in each printing place, and a correction data is added to a printing data according to the counted number. CONSTITUTION:A clock is counted while a printing range data is being inputted with a counter 21, i.e., only while the printing range is ON, and a correction data table has been preliminarily stored in a ROM 22. The correction data is read from the ROM 22 according to a counted value of the counter 21, and this correction data is added to a printing data, which is printed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of thermal printing using a thermal printer, and particularly to a method of adding correction data to print data to adjust the amount of heating of a thermal head.

0002

2. Description of the Related Art FIG. 5 shows a printing unit 1 using a conventional thermal printing method, in which a transfer film 3 coated with heat-melting or sublimation ink is pressed onto a recording medium 4 such as a card by a thermal head 2. By energizing and heating the heating resistor of the head 2, the transfer film 3 is
The ink is transferred to the recording medium 4 to perform printing, and by moving the recording medium 4, printing is performed in a predetermined range.

[0003] Here, the density when printing without adding correction data to constant print data from the printing start position is shown as "print density 1" in FIG. 6 because the temperature of the heating resistor gradually increases. It becomes like this. Therefore, conventionally, by adding correction data to the print data, the density is made to be approximately constant as shown by "Print Density 2" in the figure.

0004

[Problem to be Solved by the Invention] However, in the past, the amount of heating is set even when printing is not being performed, so when printing starts midway, the density may be insufficient or the amount of heat stored cannot be calculated. It takes time to print, which slows down the printing speed.

For example, as shown in FIG. 7, when the card-like recording medium 5 has two printed parts, a face photograph part 5a and a character part 5b such as a name, etc., as shown in FIG. The density is shown as "Print Density 3", and the density of the character part is shown as "Print Density 4", which is different from "Print Density 2" when recording is performed continuously from the printing start position. Such a difference in density becomes particularly noticeable when the printing density is high or when printing is performed at a constant density.

[0006]

[Means for Solving the Problem] In a method of thermally printing on a plurality of printing locations on a recording medium by adding correction data to print data, a counter is operated only while printing on each of the printing locations, and the number of counters is correction data is now added to the print data.

[0007]

[Operation] Since the amount of heating is set based on the distance from the heating start position of the thermal head, printing with a predetermined density can be performed at any print start position.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic diagram of a printing section to which the method of the present invention is applied, FIG. 2 is an explanatory diagram of a film used in the printing section, FIG. 3 is a block diagram of a correction circuit, and FIG. 4 is a timing chart of the correction circuit.

The thermal printer of the present invention includes a printing section 1 and an overcoat section 11.
As shown in a), the face portion 5 is printed on the card-shaped recording medium 5 shown in FIG.
a and the character portion 5b are printed, and the overcoat portion 1 is printed.
1, as shown in FIG. 2(b), the thermal head 12 applies an overcoat 5c to the printed portion of the card-shaped recording medium 5 using an overcoat film 13 impregnated with a heat-melting resin or the like to serve as a protective film. give

In this case, the face portion 5 of the card-like recording medium 5
When the overcoat portions of a and character portion 5b are designated as A and B, the transparent coat thickness is based on "Print Density 3" and "Print Density 4" in FIG. 8, but the thinner one is difficult to transfer to the recording medium. Moreover, if the overcoat film 13 is heated too much, there is a risk that the entire overcoat film 13 will stick to the recording medium.

Therefore, as shown in FIG.
4B, the clocks shown in FIG. 4A are counted only while the print range data as shown in FIG. 4(c) of the counter 21
Correction data is read out from the ROM 22 in accordance with the count value as shown in , and the correction data is added to the print data and printed.

[0012] With this arrangement, when the print range is off, the count value of the counter 21 is "0" and the reset state is entered, so even if printing starts from the middle of the recording medium, the correction data will be stored at the printing start position. It is possible to perform corrections equivalent to those described above, and it is possible to always apply an overcoat of a constant thickness. This is applicable not only to overcoating but also to partial printing at a constant density.

[0013]

[Effects of the Invention] As explained above, according to the present invention, the counter is operated only while printing is performed on each printable area on the card surface, and correction data is added to the print data according to the number of counters. Therefore, the amount of heating can be set based on the distance from the heating start position of the thermal head or this and the printing speed, and a fixed amount of transfer can be performed at any print start position, improving print quality.

[Brief explanation of the drawing]

[Fig. 1] Schematic diagram of a printing section to which the method of the present invention is applied.

[Figure 2]
Explanatory diagram of the film used in the printing department

[Figure 3] Block diagram of correction circuit

[Figure 4] Timing chart of correction circuit

[Figure 5] Diagram showing the configuration of a general printing section

[Figure 6] Graph showing the relationship between print position and density

[Figure 7] Plan view of a card-shaped recording medium with two printed parts

[Figure 8] Graph showing the relationship between print position and density of the same recording medium

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Printing part, 2, 12... Thermal head, 3... Transfer film, 5... Card-shaped recording medium, 11... Overcoat part,
13... Overcoat film, 21... Counter, 22
...ROM.

Claims (1)

[Claims] Claim 1. A thermal printing method in which correction data is added to print data when a thermal head transfers ink or resin from a film to a printing location on the surface of a recording medium such as a card, wherein the printing location is located on the surface of the recording medium. A thermal printing method in which counters are provided at a plurality of locations on a surface, are operated only while printing is performed on each of these printing locations, and correction data is added to print data in accordance with the number of counters.