JPS62169688A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To perform recording in the same state without controlling the energy applied to a thermal head on the basis of whether the transfer of ink is performed, by providing a composition having constituents almost the same as those of heat-meltable ink containing no colorant. CONSTITUTION:Beside strip like ink bands 32-34 of three colors C,M, Y of a tape like ink ribbon, a band 31 of a composition having constituents almost the same as those of the ink of each ink band containing no colorant is provided. When a color image is recorded, the composition band 31 is at first transferred to image receiving paper and, thereafter, color inks C, M, Y are successively transferred. As mentioned above, by transferring the composition band 31 to the image receiving paper at first, even if either one of the color inks C, M, Y is transferred to the image receiving paper, because of such a state that the ink was already transferred, the same state as such as case that ink is transferred so as to be superposed onto transferred color inks is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a recording medium for thermal transfer used when performing thermal recording with a thermal head.

(Technical background of the invention and its problems) As shown in FIG. 1, a thermal transfer color printer has a thermal head 2 disposed above a platen roller 1 rotated by a drive source, and the thermal head 2 and the platen roller are connected to each other. An ink ribbon 1o, which is a recording medium for thermal transfer, and an image receiving paper 20 for recording are superimposed between the recording medium 1 and 1, and are thermally transferred by the thermal head 2 while being conveyed in the direction of the arrow in the figure. Ink ribbon l.

has a thin base film (thickness 3-10 IL) 11, and the base film 1! A heat-melting ink 12 containing a coloring agent such as a dye or a pigment and, if necessary, a softener (resin, etc.) is uniformly applied thereon. The heat-melting ink 12 of such an ink ribbon 10 is applied to the receiver paper 2.
0 and held between the platen roller l and the thermal head 2, and heat is applied from the heat generating part 3 of the thermal head 2, so that the ink in the ink melting part 4 is melted and transferred to the image receiving paper 20. be done.

In such a thermal transfer color printer, when performing color thermal transfer as described above, Y of the ink ribbon lO
Thermal transfer is repeated for each color (yellow), magenta (N), and cyan (C), and a full-color image is recorded depending on the transfer area and degree of overlapping of each color. That is, for example, in a thermal printer with a serial type head, as shown in FIG. 2, an ink ribbon 1o consisting of CNY three color ink bands is arranged obliquely, and a serial thermal head 2 is placed on top of this ink ribbon io. The three color heating elements 20.2% and 2Y are arranged so as to overlap corresponding to the respective color rows on the ink ribbon 1o, and while the ink ribbon 2 is being transferred in the direction A, the thermal head 2 and the ink ribbon 2 at the same time B
After recording this l line, the thermal head 2 and ink ribbon 2 are returned to their original positions together, and the image receiving paper 2o is moved a predetermined distance in the C direction, for example. Sub-scanning is performed by moving only the By repeating such main scanning and sub-scanning, a color image can be thermally transferred and recorded on the entire surface of the image receiving paper 2o.

As mentioned above, conventional thermal transfer color printers use YNC
The color ink on the ink ribbon 1o consisting of a colored band is transferred to the receiver paper 2.
0, the recording sensitivity differs between when color ink is first transferred to the image receiving paper 20 and when the next ink is transferred after the ink has already been transferred.
Therefore, it was necessary to correct the amount of energy applied to the thermal head.

Figure 3 shows the relationship between the input energy E of the thermal head and the density of the recorded image.
For example, the density characteristics when ink is first transferred to P
When ink has already been transferred and another color ink is transferred, the density characteristic becomes low as shown in Q, and the ink is transferred to the image receiving paper 20 first, or the ink has already been transferred. The recording density differs depending on whether ink is transferred on top of the original color. Therefore, it was necessary to take this point into account and control the energy input to the thermal head.

(Object of the invention) This invention was made under the above circumstances,
The purpose of this invention is to uniformize image density characteristics by thermal transfer without controlling input energy when transferring another ink on top of already transferred ink of a certain color and when transferring ink first. It is an object of the present invention to provide a recording medium for thermal transfer which can be used for various purposes.

(Summary of the Invention) This invention provides, in addition to heat-melting inks of three colors C, M, and Y, a white or colorless transparent ink having almost the same composition as the heat-melting ink except for the coloring agent. This is a recording medium for thermal transfer in which a composition is layered on a support (for example, a film base, paper, etc.).

(Embodiment of the Invention) In this invention, as shown in FIG. 4, these ink strips are placed next to the strip-shaped ink strips 32 to 34 of three colors of CMY on the tape-shaped ink ribbon 1O as shown in FIG. 2. A band 31 of a composition having approximately the same composition as that of the ink other than the colorant is continuously provided. When recording a color image, the composition band 31 is first transferred to the image receiving paper, and then CMY and color inks are sequentially transferred.

In this way, by first transferring the composition band 31 to the image-receiving paper, no matter which color ink of CNY is transferred to the image-receiving paper next, the ink has already been transferred. It is possible to create exactly the same state as when ink is transferred on top of the already transferred ink.

FIG. 5 shows another embodiment of the invention, in which a composition 4 similar to that described above is applied on a tape-shaped base film 40.
1 and CMY color inks 42 to 44 are sequentially and repeatedly layered. In this case as well, the composition 41 is first transferred onto the image receiving paper, and then the CNY color inks 42 to 44 are transferred.

The composition includes a binder and, if necessary, a softener (
It is a composition to which a whitening agent (resin, etc.), whitening agent, etc. are added, and it can be connected or layered by hot melt coating, solvent coating, etc. The binder is preferably carnauba wax, microcrystalline wax, etc., and may also be a composition containing a petroleum resin softener, a colloidal silica extender, or a thermally conductive substance such as aluminum powder.The composition is white or colorless. Any transparent material is sufficient, and titanium white, barium sulfate, or the like is used as the whitening agent.

(Effects of the Invention) As described above, according to the thermal transfer recording medium of the present invention, since a composition having almost the same composition as that other than the colorant contained in the heat-melting ink is provided, thermal It is possible to perform recording in the same state without controlling the energy input to the head depending on whether ink has already been transferred or not.

[Brief explanation of drawings]

Figure 1 is a diagram showing an example of a thermal transfer printer, Figure 2 is a diagram for explaining an example of recording with an ink ribbon, and Figure 3 is a diagram showing the case where ink is first transferred to receiver paper and the case where ink has already been recorded. FIGS. 4 and 5 are plan structural views showing one embodiment of the present invention, respectively, for explaining the difference in characteristics from the case where another ink is transferred onto the ink. l...Platen roller, 2...Thermal head/F
, 3... Heat sensitive part, 10... Ink ribbon, 20...
- Image receiving paper for thermal transfer recording, 30.40...Recording medium for thermal transfer, 31.41...Composition.

Claims (3)

[Claims] (1) In addition to the three-color heat-melt ink of C, M, and Y, a white or colorless transparent composition having almost the same composition as the heat-melt ink except for the colorant is placed on the support. A recording medium for thermal transfer characterized by being layered. (2) the support body is tape-shaped;
2. The recording medium for thermal transfer according to claim 1, wherein heat-melting inks of three colors M and Y and the composition are arranged side by side in a band shape in the longitudinal direction of the support. (3) The support body is tape-shaped, and the C.
2. The recording medium for thermal transfer according to claim 1, wherein heat-melting inks of three colors M and Y and the composition are repeatedly provided in order in the lateral direction of the support.