JPH0281668A - Thermally fusible transfer paper - Google Patents

Abstract

PURPOSE:To make possible the excess sticking to recording paper of thermally fusible ink and thereby an accurate gradation control during high-density recording while the satisfactory sticking to the paper of the ink during low-density recording is ensured, by arranging the ink in a specifically spaced halftone dot style. CONSTITUTION:The subject paper consists of a polyester film base 10 and thermally fusible ink of the same quality which is applied on the surface of the former in almost a uniform thickness and a halftone dot style. The interval between the dots is equal to or less than the space between thermal elements of a thermal head on a thermal printer used. Consequently, during high-density printing, each halftone dot of thermally fusible ink 11 does not attract an adjacent halftone dot of the ink 11. In addition, during low-density printing, dots of the ink 11 other than those of a recorded section are not attracted by the dots of the ink 11 in the recorded section. Thus it is possible to control accurately the transfer area of the thermally fusible ink 11 to recording paper, and achieve an accurate gradation control to ensure a satisfactory printing condition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat-sensitive melt transfer paper used in a thermal printer.

(Prior Art) Conventionally, as shown in Fig. 4, heat-sensitive melt transfer paper used in thermal printers has a surface (upper surface in the figure) of a polyester film base 1 with a thickness of about 5 to 6 μm.
It is generally known to have a structure in which a heat-melting ink 2 is evenly applied to the entire surface.

The thermal printer is configured such that the heat-melting ink 2 of such heat-sensitive melt transfer paper is brought into contact with the recording paper 3, and the thermal head 4 is brought into contact with the back surface (lower surface in the figure) of the base 1. By applying a predetermined current to this thermal head 4 and generating heat, the heat-melting ink 2 is melted and transferred onto the recording paper 3, thereby printing predetermined characters and figures on the recording paper 3. It has become.

In addition, when performing color printing, use heat-sensitive melt transfer paper on which heat-melt inks of colors such as yellow, mapinta, cyan, and black are applied to the base 1 in a random pattern, one screen at a time, - for each color. By repeating printing with heat-melting ink, each color is overlapped to produce color printing.

Furthermore, by variably controlling the level of the signal current flowing through the thermal head 4, the amount of the heat-melting ink 2 to be melted can be varied, and thereby the recording paper can be printed as shown in FIGS. By varying the area of the heat-melting ink transferred to No. 3, the gradation of printed figures, etc. <a degree) was expressed.

(Problem to be Solved by the Invention) By the way, when printing is performed using the conventional heat-sensitive melting transfer paper as described above, the level of the signal current flowing to the thermal head 4 is also low in areas with low density. Ink 2 is not completely transferred from base 1 to recording paper 3,
As shown by the dotted line in FIG. 5(A), there were cases where the dots 5 formed by the heat-melting ink were chipped.

In addition, in areas where ma is high, the level of the signal current flowing to the thermal head 4 is also high, so that the heat-melting ink 2 is excessively melted from the base 1, as shown by the dotted line in the middle of FIG. 5(B). There were cases where adjacent dots 5.5 were connected to each other.

In such a case, the area of the heat-melting ink on the recording paper 3 will change, making it impossible to accurately control the gradation, making it impossible to print clearly, and the color tone will also be distorted. Put it away.

In addition, heat-melt ink 2 in conventional heat-sensitive melt transfer paper
must be applied uniformly to the entire surface of base 1,
It was necessary to perform so-called solid painting.

For this reason, a special coating device is required to manufacture this type of heat-sensitive melt transfer paper, which has the drawback of being difficult to manufacture and is a factor that hinders cost reduction.

<Means for Solving the Problems> The present invention has been made in view of the above-mentioned circumstances, and provides a heat-sensitive device that can realize clearer recording, is easy to manufacture, and can reduce costs. The purpose is to provide melt transfer paper.

In order to achieve this object, the present invention provides the above-mentioned heat-sensitive melt transfer paper in which heat-melt ink applied to the surface of a base is melted by heating from the back surface of the base and transferred to recording paper. The present invention provides a heat-sensitive melt transfer paper characterized in that heat-melt ink is arranged in the form of halftone dots at predetermined intervals.

(Example) Hereinafter, a preferred example of the heat-sensitive melt transfer paper according to the present invention will be described in detail with reference to FIGS. 1 to 3.

FIGS. 1(A) and 1(B) are a plan view and a cross-sectional view showing an embodiment of the heat-sensitive melt transfer paper according to the present invention, and this heat-sensitive melt transfer paper has the same heat melt on the surface of the base 10 made of polyester film. The thickness of the ink 11 is approximately average (approximately 2 to 3 μm).
It is made up of a halftone dot pattern.

The halftone dots (drill 1-) of the heat-melting ink 11 are each formed in the shape of a circular dot, as shown in FIG. This is set to be approximately equal to or less than the interval (6 to 12 dots/1 m) between the heating elements of the thermal head of a thermal printer.

As a result, during high-density recording, each dot-shaped heat-melt ink 11 to be transferred can be easily transferred from the base 10 of the heat-sensitive melt transfer paper to the recording paper without pulling the adjacent dot-shaped heat-melt ink 11. Since the transferred heat-melting ink 11 is better separated from the base 10 in the B density recorded area, the adverse effect on the adjacent area is reduced.

Furthermore, during low-density recording, the dot-shaped hot-melt ink 11 other than the recorded portion is not pulled by the dot-shaped hot-melt ink 11 in the recorded portion, and as a result, the hot-melt ink 11 in the low-density recorded portion is The transfer state to the recording paper becomes better.

Therefore, by using the heat-sensitive melt transfer paper according to this embodiment, it is possible to accurately control the transfer area of the heat-melt ink 11 onto the recording paper, thereby enabling accurate gradation control and improving the printing state. It can be made good.

In addition, such dot-shaped heat-melting ink 11 is
Since the coating can be applied to the base 10 in a process similar to that of normal halftone dot printing without the need for solid coating, this type of heat-sensitive melt transfer paper can be manufactured easily and costs can be reduced. can.

Also, the inclination (θ) of the dot array of the thermofusible ink 11 of multiple colors such as yellow (Y), magenta (M), and cyan (Gy) applied in a random pattern on the surface of the base 10
is changed for each color with respect to the transfer paper running direction as shown in FIGS. 2(A) to (C), for example, the inclination (θ
) are 90°, 60° and 45°, respectively.

In this way, by changing the inclination of the dot rows of the heat-melting ink 11 of each color, errors in overlapping colors (color shift) become less noticeable, improving color reproducibility, and eliminating beat-shaped moiré. can be prevented from occurring.

In addition, in this embodiment, as shown in FIG.
Apply it to the entire surface of 0.

Thereby, before transferring the heat-melting ink 11 of each color onto the recording paper, the binder 12 can be applied to the recording paper in advance to smooth the surface of the recording paper.

Therefore, by using the heat-sensitive melt transfer paper according to this embodiment, a good recording state can be obtained even when recording is performed on plain paper whose surface is not smooth.

Incidentally, in the above-mentioned embodiment, the area of each dot is set so that each dot-shaped thermofusible ink 11 is adjacent to each other, but the area of each dot may be made smaller as shown in FIG. .

However, if the area occupied by the heat-melting ink 11 with respect to the base 10 is more than 90%, the dots will come into close contact with each other.
If it is less than 50%, the S degree at the time of recording will be too low, so
As a result of experiments, it was found that it is preferable to set the ratio between 0x and 90%.

Additionally, the shape of each dot is not limited to a circle;
It may have various shapes such as a square, a hexagon, or a diamond.

(Effects of the Invention) As is clear from the above description, according to the present invention, it is possible to improve the adhesion of heat-melting ink to recording paper during low-density recording, and to improve the adhesion of heat-melting ink to recording paper during high-density recording. It is possible to prevent excessive adhesion of the color ink to the recording paper, thereby realizing accurate gradation control.

Furthermore, the dot-shaped hot-melt ink according to the present invention can be applied to a base in substantially the same process as normal halftone dot printing without requiring solid coating.

Therefore, this kind of heat-sensitive melt transfer paper can be manufactured easily and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1(A)<8) is a diagram showing an embodiment of the heat-sensitive melting transfer paper according to the present invention, in which FIG. 1(A) is a plan view and FIG.
) is a sectional view of B-8 in the same figure (A), and Fig. 2 (A) ~
(C) is a plan view showing the application patterns of heat-melting ink of each color, FIG. 3 is a plan view showing another embodiment, and FIG. 4 is a thermal head, recording paper, and heat sensitive in a general thermal printer. Side view showing the positional relationship with the melt transfer paper, No. 5
Figures (A) and (B) are plan views showing the recording state;
A) is a plan view of a low-density recording portion, and CB> of the same figure is a plan view of a high-density recording portion. 10...Base, 11...Thermofusible ink. Figure 1 (,4) (t3) (C) Figure 12

Claims (1)

[Claims] In heat-sensitive melt transfer paper, the heat-melt ink applied to the surface of the base is heated from the back side of the base to melt it and transfer it to the recording paper, in which the heat-melt ink is arranged in the form of halftone dots at predetermined intervals. A heat-sensitive melt transfer paper that is characterized by: