JPS5964384A - Printing method using heat foamable ink - Google Patents

Abstract

PURPOSE:To perform printing using head foamable ink imparting beautiful finish and having good efficiency in low cost, by further applying color ink onto the heat foamable colorless ink printed to an object to be printed to perform double printing. CONSTITUTION:For example, arbitrary printing is performed onto an object 1 to be printed by using heat foamable colorless ink (ink prepared by mixing a synthetic resin microcapsule with a particle size of 10-30mum having butane enclosed therein in a vehicle) 2, for example, according to an offset method and, thereafter, usual color ink 3 is used to be superposed on the heat foamable ink 2 to perform double printing, for example, according to an offset method. After printing, the object 1 to be printed is passed between hot rollers 4, 4' heated to 120 deg.C or more to perform objective printing while foaming the heat foamable ink 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing method when printing using a thermally foamable ink.

Thermofoamable ink is an ink containing a foam ("Microcapsule", a registered trademark of Dow Chemical Company) that foams with heat. Microcapsules are mixed in with pigments or dyes in advance during the ink manufacturing process. For this reason, in order to bring out the color of the ink, it is necessary to increase the amount of pigment or dye, and when foaming, the ink loses its gloss or becomes pale.

Furthermore, since it is necessary to prepare in advance a large number of different colors of thermally foamable ink during printing, there is a drawback that the cost is particularly high for colors that are used only in subtotals. In addition, in the case of colored heat-foamable inks, the printing speed is slow, resulting in problems such as viscoelasticity and drying properties, resulting in poor printing quality and bitterness, and in the case of multicolor printing, printing efficiency is greatly reduced. There was a drawback.

The present invention was proposed with the aim of improving these drawbacks, and the thermally foamable ink has a composition consisting only of a vehicle and microcapsules, and does not contain any pigments or dyes. Using this ink, first, arbitrary characters, patterns, etc. are printed on a printing material, and the characters, patterns, etc. to be thermally foamed are specified. Next, on the letters and patterns printed with this thermally foamable ink, ordinary ink (colored ink) is used to print turned letters and patterns. If you select the color of ink to be printed later, it will look like characters and patterns of any color are printed on the printing material.

After double printing in this way, when the printing material is heated by an arbitrary method, for example, by passing it between pot rollers, the thermally foamable ink side foams and the printed area swells, forming colored three-dimensional letters or patterns. becomes.

Embodiments of the present invention will be described in detail below. First, as shown in FIG. 1, arbitrary printing is performed on a printing material 1 using a colorless thermally foamable ink 2 in which microcapsules are mixed in a vehicle.

Note that this printing is performed using any printing method such as offset or gravure.

Next, as shown in FIG. 2, colored printing is carried out using a normal colored ink 3 superimposed on the thermally foamable ink 2.

Note that this colored printing is performed using any known printing method such as offset, gravure, and silk printing.

Next, as shown in FIG. 3, a pot roller 4.4 heated to 120°C or more
' to foam the thermally foamable ink 2.

Note that the heating means for the printing medium 1 is not limited to one type of pot roller.

FIG. 4 shows a cross section of the printing material after foaming, in which only the thermally foamable ink 2 is foamed, and the colored ink 3 has a cross-sectional shape on top of the thermally foamable ink 2.

In addition, when printing the thermally foamable ink 2 and the colored ink 3, when both are the same, or when printing the colored ink 3 so as to color only -)41S on the thermally foamable ink 2, or when printing the thermally foamable ink 2 and the colored ink 3, There are cases where the printing material 1 is widely printed with the colored ink 3 so as to surround the ink 2, and this is determined based on the design of characters, patterns, etc.

Therefore, according to the present invention, when the printing material is heated, the colored ink 3 does not foam at all, so the color in the thermally foamed ink area is completely the same as in normal printing, resulting in a beautiful thermal foaming finish. This has the effect of producing printed matter using ink.

Further, printing of the portion to be thermally foamed using the thermally foamable ink 2 can be completed by printing once on the printing material 1. So-called multi-color printing for coloring usually suffices with a printing method using ordinary ink. Therefore, since high-speed printing is possible for color printing, printed matter using thermally foamable ink can be produced efficiently and at low cost.

Note that thermally foamable ink is a synthetic resin (thermoplastic MI Jl' whose main component is vinylidene chloride) with a particle size of 10 to 30μ.
Fi) Butane is encapsulated in microcapsules, and the microcapsules are mixed and dispersed in a vehicle and used as a solvent. When heated above 120°C, the microcapsules become 4 to 5 times larger in diameter and 70 to 100 times larger in volume. It expands to.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an example of printing a thermally foamable ink on a printing material, Fig. 2 is a cross-sectional view showing a state in which colored ink is printed on the thermally foamable ink, and Fig. 3 is a cross-sectional view showing a method of foaming. FIG. 4 is a side view of a hot roller showing an example, and a cross-sectional view showing a printing medium on which thermally foamable ink is foamed. 1... Printing material, 2... Heat foaming ink, 3... 77 color ink, 4.4'...
Hot roller 〇Figure 1 Figure 2 Figure 3 Figure 2/Figure 4 489-

Claims (1)

[Claims] (]) Characters are printed on a printing medium using colorless thermally foamable ink.
A printing method using heat-foamable ink, in which the surface of the heat-foamable ink is colored arbitrarily by printing a pattern, etc. and then double printing on top of this printing using colored ordinary ink. . (2) Use of the heat-foamable ink according to claim 1, wherein printing for coloring the surface of the heat-foamable ink is one of the printing methods including offset, gravure, silk, etc. printing method.