SU376956A1 - METHOD NILUCHENYA TEMPORARY SUBSTRATE FOR PRINTING - Google Patents

Description

one

This invention relates to the use of a method for producing a temporary substrate for printing using dyes that become vaporized at 160 °.

A known method for producing a temporary substrate for printing is applied by applying an image with water-based paint on a substrate, which contains a dye that passes into a vapor state at 120-220 ° C in the form of a dispersion and a binder. Temporary substrates are obtained, for example, on sheets of paper or aluminum. The disadvantages of the method are the inadequate wetting of the paint rollers, the difficulty of preparing the paints themselves, as well as their insufficient resistance — the tendency to precipitate upon the addition of alcohol to improve the wetting of the paint roller. Such greater or lesser durability of the paints used causes an undesirable change in shades. For example, it is difficult to draw a continuous line consisting of several colors, since, in spite of a careful liner, it is almost impossible to avoid some displacement and, therefore, some break in the line when moving from one color to another. In addition, by the wear method it is quite difficult to remove

AND

Excess kpaciiH. For example, it is not possible to switch from one color to another without significantly increasing the volume of paint. It is also difficult to completely clean the rollers once rolled with paint, which entails the formation of a "veil, which may not be visible on paper, but may cause considerable difficulties subsequent use of the footprint.

In order to improve the quality of the resulting image and simplify the process of transferring it according to the proposed method, anhydrous paint containing an organic solvent is used.

The proposed method consists in applying an image to a backing of sheets, tapes, strips, and other suitable forms using an anhydrous paint, which is a solution or a fine dispersion in an organic solvent, but preferably in a low molecular weight monohydric alcohol, in a complex, ketone. or a mixture of the latter, at least one dye, passing into the vapor state at 150-220 ° C and atmospheric pressure and compatible with the solvent, and a thermostable binder or thickener with m.p. not below 25b ° C.

The proposed method allows to print

on a surface whose affinity to the dyes used is negligible or insignificant, for example, on the surface of paper or metal foil, preferably aluminum, with paints containing organic dyes, for example azo compounds or anthraquinone, with a boiling point or sublimation within 160-210 ° C, and these dyes are dissolved or finely dispersed in an organic solvent or mixture of organic solvents that boil at atmospheric pressure at a temperature below 120 ° C, preferably below 105 ° C, and may contain up to 15% binder, consisting mostly of cellulose ethers. If paper substrates are used, it is advisable to choose a non-porous

OnN

paper. The proposed method allows the use of aluminum foil substrates without special measures to facilitate wetting, i.e., setting the paint with aluminum foil, as is required by known methods.

Known dyes are used to make paint. They can belong to a wide variety of classes of compounds. For example, pigment dyes from a series of anthraquinone and azo dyes, mainly monoazo compounds, as well as derivatives of styrene, nitrodiphenylamine or chinophthalone are used.

As dyes, for example, compounds of the following formulas can be used:

he . CH, -CO-NH VK.N-

he,

. 02N (I N-N-QbNH

-CH

 V vvt / 2 it

- Chg-yr / h

 H CH20H

About -N- -C-C ./and II

c, k

/ - /

but N

, N About KN,

about I.,

but oh he

Oh NH

С1-ШгН., С СООС.Нь

/ Z /

ScNGGft

oh wh

) -OCHNz

CO-NH

Oh NH

 About NH2

HoN Oh NH,

C7HsO- r N- CH C

GN

CH

, -cn, -cn, -co-C o iJ-.

 /

Ch.

Preferably, dyes with similar thermal characteristics are used, for example, the sublimation curves of which are most similar to each other in the range of 180-200C.

Cellulose ethers, for example nitrocellulose, and in particular those cellulose ethers which contain alcohol residues of low molecular weight, for example methylly ethylcellulose, hydroxyethyl and especially oskipropilcellulose, are preferably used as binders.

The best method for preparing paints is to use dye preparations that already contain the necessary binders. These preparations are finely divided powders containing one or more sublimated dyes, thoroughly mixed with cellulose ester or ether. The relative content of the dye in them can vary considerably; it is mainly 40-60%. These preparations are easily dispersed in organic solvents. The solvents used are predominantly those that boil at temperatures below 120 ° C and at atmospheric pressure and do not contain water. Examples of such solvents are anhydrous or nearly anhydrous alcohols, such as ethyl, methyl, propyl, or ketones, such as methyl ethyl ketone, or esters, such as ethyl acetate or propyl; It is also possible to use mixtures of these solvents in which the dye preparations are easily dispersed. The viscosity of the paint can be easily adjusted by adding an additional amount of binder or diluting it with a suitable solvent.

Typically, one or more ink rollers, such as metal, are usually used for printing.

After printing the substrate, the solvent or solvents used to make the ink are evaporated and, if possible, regenerated.

The durability of the inks used by the proposed method and the versatility of the method allow printing a variety of patterns with accurate color registration on paper or aluminum foil, which is much better than that of previously known methods.

Example 1. With the help of several relief (engraved) paint rollers, multicolor images are printed on paper tape, narrow or wide, using paint made, for example, as follows.

With strong agitation, 12 hours of dispersion containing 50% of the dye of the formula are shifted

thirty

35

in 50% hydroxypropyl cellulose (average particle size of the indicated dye in a dispersion is 1 micron), from 5 h, ethyl cellulose in 78 parts of isopropyl alcohol. Get yellow paint.

Blue paint is obtained similarly, but take 8 hours of dispersion containing about 50% of the dye of the formula

WITH

NH-CO-CH7GH7CH5

g / V7 in 50% hydroxypropylcellulose. For the synthesis of red dye, a mixture of 50% ethylcellulose and 50% of the dye of the formula is used. After drying, images are printed in 30, the clarity of which lines and the register of colors are excellent. Example 2. The process is carried out as in Example 1, but as a temporary substrate, aluminum foil is 6 microns thick, 35 which is printed with a paint roller and dried. The following compounds can be used as dyes: СН. СН70СН7СНз СО / ™ t), N ,, SH, (V - H, N т,) 7Н, ОН 3) IJl

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Example 3. A lacquer base was prepared by mixing 6 parts of ethyl cellulose and 94 parts of isopropyl alcohol. To the mixture is added a dye preparation consisting of