JPS6140171A - Recording method for thermal transfer printer - Google Patents

Abstract

PURPOSE:To enable clear printed patterns with excellent dot reproduction to be obtained even on an image-receiving paper poor in smoothness, by a method wherein the second printed patterns the same as a part or the entire part of the first printed patterns are provided on the first printed patterns by a rear row of heating elements. CONSTITUTION:In a thermal printing head 1, a pair of front and rear heating element rows 6, 7 comprising a plurality of heating elements 5... in a row are provided in parallel with each other on a substrate 8. The head 1 is slidden in the transverse direction (a) of the image-receiving paper 3 by a sliding means (not shown). A part or the entire part of the first printed patterns are reprinted by the rear heating element row 7. Namely, the second printed patterns the same as a part or the entire part of the first patterns are provided overlappinly on the first printed patterns by the rear heating element row 7, accordingly a clear printed pattern as shown in Fig. 4 can be finally obtained even on the image- receiving paper 3 with a low smoothness.

Description

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

<Prior art> In general, this type of thermal transfer printer uses a transfer film whose surface is coated with ink and is interposed between a thermal printing head and an image receiving paper, and heats the thermal printing from the back side of the transfer film with a V. This transfers the ink to the image-receiving paper that is in close contact with the surface of the transfer film, and prints the desired pattern on the image-receiving paper. Since there is no particular restriction on the image-receiving paper to be used and plain paper can be used, various kinds of plain paper are used by users.

<Problems to be Solved by the Invention> By the way, conventionally, a thermal printing head has a single row of heating elements arranged in a row, and this row of heating elements prints on the image receiving paper using the method described above. A printed pattern was formed. However, in this case, for example, if a receiving paper with a low smoothness is used, the surface of the receiving paper is rough, so the adhesion between the ink-coated surface of the transfer film and the surface of the receiving paper is poor, and the ink is completely absorbed into the receiving paper. Not transferred to the surface. As a result, the dot reproducibility deteriorates, the print pattern becomes unclear, and the print quality deteriorates significantly. It is also possible to improve printing quality by forming the same printing pattern overlappingly on the same printing surface using the heating element array, but this would double or more the printing speed. This is inefficient.

In view of the conventional problems, it is an object of the present invention to make it possible to obtain a clear printed pattern with excellent dot reproducibility, even if, for example, the image receiving paper has low smoothness.

<Means for Solving the Problems> In order to achieve the above object, the present invention includes a thermal printing head, and transfers the thermal printing onto a transfer film interposed between the thermal printing head and the image receiving paper. 19. In thermal transfer printing, in which ink from a transfer film is transferred to image-receiving paper and a desired pattern is printed on the image-receiving paper, the thermal printing head is equipped with a plurality of heating elements arranged in a row. A pair of heating element rows are arranged in front and back in parallel, and the first printing pattern is formed on the image receiving paper by the heating element row of the former stage, and the heating element row of the latter stage is formed on the first printing pattern. The present invention is characterized in that it is possible to perform a type of printing in which a second printing pattern having the same pattern as part or all of the first printing pattern is overlapped depending on the body arrangement.

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

FIG. 1 is a schematic side view of a serial type thermal transfer printer in which the present invention is implemented. In this figure, this thermal transfer printer includes a serial type thermal printing head 1 and a platen 2 disposed opposite to the thermal printing head 1. As shown in FIG. An image receiving paper 3 and a transfer film 4 are fed between the platen 2 and the thermal print head 1. As shown in FIG. 2, in the thermal printing pad 1, a pair of heating element rows 6 and 7, which are formed by arranging a plurality of heating elements 5 in a row, are arranged parallel to each other on the front and back of the substrate 8. The heating element rows 6 are arranged so as to slide in a direction A across the image receiving paper 3 by a sliding means (not shown), and the required portions of each of the front and rear heating element rows 6 generate heat when energized by a heat generating driving means (not shown).

In a thermal transfer printer with such a configuration, the thermal printing head V1
By heating the transfer film 4 interposed between the image receiving paper 3 and the image receiving paper 3, the ink on the transfer film 4 is transferred to the image receiving paper 3, and a desired pattern is printed on the image receiving paper 3. be done. In this case, a first print pattern as shown in FIG. 3, for example, is first formed on the image-receiving paper 3 by the heating element array 6 in the previous stage. As shown in FIG. 3, the first print pattern becomes less clear as a whole as the smoothness of the image receiving paper 3 decreases.

For this reason, in the present invention, part or all of the printing pattern is overprinted on the first printing pattern by the heating element array 7 at the subsequent stage.

In other words, the heating element array 7 in the latter stage superimposes a second print pattern having the same pattern as the first print pattern on top of the first print pattern, ultimately resulting in an image reception with low smoothness. Even on paper 3, a clear print pattern as shown in FIG. 4 can be obtained.

FIG. 5 is a characteristic diagram showing the relationship between the smoothness of the image-receiving paper 3 and the reflection density of the print pattern formed on the image-receiving paper 3 when printing is performed on the image-receiving paper 3 with a predetermined applied energy. In this figure, a characteristic line A shows the characteristics of a conventional printing pattern that is printed only once, and a characteristic line B shows the characteristics of a printing pattern that is printed repeatedly according to this embodiment. As is clear from this figure, regardless of the degree of smoothness, the reflection density of the printed pattern according to this example is significantly improved compared to the conventional one.

Note that depending on the characteristics of the image-receiving paper 3, the first printing pattern may become partially unclear as shown in FIG. It is also possible to overprint only the unclear portions.

FIG. 7 is a schematic front view of main parts of another embodiment, showing a line-type thermal transfer printer embodying the present invention, in which the same parts as in the embodiment of FIG. 1 are given the same reference numerals. That is, 1
2 is a line-type thermal printing head, 2 is a platen, 3 is an image receiving paper, 4 is a transfer film, 6 and 7 are front and rear heating element rows, and 8 is a substrate of the thermal printing plate 1.

In this embodiment as well, after the first printing pattern is formed on the image receiving paper 3 by the heating element row 6 in the former stage, a second printing pattern is superimposed on the first printing pattern by the heating element row 7 in the latter stage. It is formed by

<Effects of the Invention> As described above, according to the present invention, a pair of heating element rows are arranged in front and in parallel in a thermal print head, and a first printing pattern is formed on the image receiving paper by the heating element row of the previous stage. At the same time, a second printed pattern having the same pattern as a part or all of the first printed pattern is superimposed on the first printed pattern by a heating element in a subsequent stage.
Even when printing on receiver paper with low smoothness and rough paper surface, a clear print pattern can be obtained and the print quality can be maintained at a high level. Furthermore, while the second printing pattern is being formed on the first printing pattern by the heating element row in the latter stage, the first printing pattern in the next row can be simultaneously formed by the heating element row in the preceding stage. , it is possible to print at the same printing speed as conventional one-time printing.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a serial type thermal transfer printer in which the present invention is implemented, FIG. 2 is a schematic plan view of the main parts of the thermal print head, and FIG. 3 is an example of the first print pattern formed on image-receiving paper. FIG. 4 is a plan view showing the final printed pattern, and FIG. 5 is a characteristic diagram showing the relationship between the smoothness of the image receiving paper and the reflection density of the printed pattern formed on the image receiving paper. ,
FIG. 6 is a plan view showing another example of the first print pattern formed on the image receiving paper, and FIG. 7 is a schematic front view of the main part of another embodiment. DESCRIPTION OF SYMBOLS 1... Thermal print head, 3... Receiving paper, 4... Transfer film, 5... Heating element, 6... Front row of heating elements,
7...Late row of heating elements. Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] (1) A thermal printing head is provided, and by heating a transfer film interposed between the thermal printing head and the image-receiving paper, the ink on the transfer film is transferred to the image-receiving paper, and the ink on the transfer film is transferred to the image-receiving paper. In a recording method for a thermal transfer printer, in which a desired pattern is printed on a thermal printing head, a pair of heating element rows each having a plurality of heating elements arranged in a row are arranged in parallel in front and back of the thermal printing head; A first printing pattern is formed on the image receiving paper by the heating element row in the former stage, and a part or all of the first printing pattern is formed on the first printing pattern by the heating element row in the latter stage. A recording method for a thermal transfer printer, characterized in that printing is performed by overlappingly forming second printing patterns having patterns.