JPS61268496A - Counter-etching of multi-color printing - Google Patents

Abstract

PURPOSE:To raise the decorativeness of printings by subjecting a multi-color printing with a heat-softening ink to a hot-pressing process from its printed face by using a mirror-face roll having the same circumferential pitch as the printing pitch. CONSTITUTION:The surface of a polyethylene terephthalate film of a thickness of 6mum, printed with three-color (yellow, red, and blue) in hot-melt inks of a melting point of 70 deg.C, is heated to 75 deg.C and then subjected to a continuous hot-pressing process of a linear pressure of 200g/m by using a Cr-plated iron roll having the same circumferential pitch as the printing pitch of the printing. The film so treated is concurrently ccoled to obtain a printing with a nearly mirror-face inked surface in a continuous manner. When the printing, as a thermal transfer film, is used for printing, the uniform printing with good sensitivity can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for leveling multicolor printed matter printed using heat-softening ink.

Specifically, multi-color printed matter printed using heat-softening ink is heated from the printed surface using a mirror roll with a circumferential pitch that is the same as the printing pitch.

The present invention relates to a method for leveling the printed surface of a multicolor printed matter, which is characterized by applying pressure.

(Conventional technology) Generally, when printing patterns continuously.

This is why it is difficult to control the shape of the printing ink surface, except in special cases where the pattern is completely continuous in the printing flow direction.

After the printing ink has been transferred to the substrate, the surface shape has been controlled mainly by mechanical methods, and in the case of heat-softening printed materials, by a combination of thermal methods. A typical example is embossing printed matter on PVC sheets using an embossing molding plate. This method involves heating the printed matter, then cooling and embossing it while pressing it with a metal molding pot. It is something.

(Problem to be Solved by the Invention) In practice, the softening of the printed matter, especially the ink surface, during suppression is limited because it causes ink transfer to the surface.

Therefore, shaping is mainly done by mechanical pressure,
This method is not only difficult to apply to printed materials that are not mechanically strong, but also has a relatively slow forming speed.Furthermore, the high pressure during forming reduces slippage between the printed material and the forming plate. This poses a practical difficulty because it is difficult to correct deviations when the patterning is done continuously and in sync with the pattern.

This is the same even when a forming plate having a forming pattern that is the same as the pattern is used.

(Means for Solving the Problems) The present invention has been made in view of the above circumstances, and uses a mirror roll having a circumferential pitch that is the same as the period of the printed pattern as a template for forming an ink surface. By using this, the contact position of the roll surface with the pattern is kept constant, and it is possible to compensate for slippage that inevitably occurs during continuous work. In this case, the heating of the heat-softening ink and the contact pressure of the roll against the printed matter vary depending on the properties of the printed matter and the ink, but known heating methods and appropriate pressures can be selected.

(Function) The present invention combines the well-known idea of shaping the surface of a heat-softening layer by heating and pressing, and the well-known method used for registering multicolor patterns in printing. We started by considering how to make the surface smooth, and by using a hard roll with a mirror-like surface, such as a chrome-plated metal roll, we decided to use a hard roll with a mirror surface, such as a chrome-plated metal roll. limited to, and
allowing slippage between the print and the roll;
By setting the circumference of the forming roll at the same pitch as the repetition of the pattern in the flow direction of the printed material, the pattern of the printed material corresponds in principle to a fixed position on the roll surface, thereby improving the transfer of ink to the forming roll. By combining these two methods, the surface of the heat-softening ink layer of multi-colored printed matter can be continuously and effectively smoothed by eliminating the occurrence of defects due to re-transfer to the printed matter, even when this occurs. It has been reached.

By these two means, it has become possible to transfer the surface shape of the mirror roll to the surface of the printed matter without considering retransfer of the pattern ink to other parts of the printed matter.

(Example) A printed matter was printed in three colors of yellow, red, and indigo using hot melt ink with a melting point of 70°C on a polyethylene terephthalate film with a thickness of 6 μm.The surface of the printed matter was heated to 75°C. Pressing was carried out continuously with a chromium-plated iron roll having the same circumference as the printing pitch with a linear pressure of 20.09/m.

By cooling at the same time, it was possible to continuously obtain printed matter having an ink surface shape close to a mirror surface.

When this printed matter was used as a thermal transfer film and printed with a printer, uniform and sensitive printing results were obtained.

(Effects) According to the present invention, the decorative effect of the printed matter itself can be improved by smoothing the surface by removing the uneven layer of ink that is seen on the conventional printing surface, that is, defects such as smudges, unevenness, and pinholes. At the same time, the same effect can be achieved when this printed material is rolled and used as a special material.In particular, if it is used in a thermal transfer film, it can reduce the gap between the heating head, the transfer film, and the transfer paper. By eliminating this, printing performance at high speed and low energy can be improved.

Claims (1)

[Claims] (1) Multicolor printed matter printed using heat-softening ink is heated and pressed from the printed surface using a mirror roll having the same circumferential pitch as the printing pitch. How to align printed matter