SU719896A1 - Composition for coating the underside of copying paper - Google Patents

Description

 The invention relates to coating compositions for the back side of copy paper for contact copying when printing or writing. A coating of the back side of carbon paper containing a binder — polyethylene, polypropylene or their mixture, as well as a solvent — gasoline or carbon tetrachloride, is known. 1.ii also known are compositions of short coatings applied on the reverse side of carbon paper, in contrast to the color of the copier. Such coatings contain a dye or pigment, a binder - polystyrene and a lightly volatile solvent - trichlorethylene 2. However, the use of volatile solvents in these compositions causes difficulties associated with the need to follow special safety procedures and there is an increase in the cost of the process due to the additional costs for solvents whose losses are significant, it is necessary to install special equipment for the removal and collection of solvents and additionally special equipment in the factory of technical papers. . It is also known to compose guards of the back side of carbon paper, melt-applied and containing natural or synthetic waxes and pigments. The disadvantage of such compositions is the technological difficulties in their manufacture. Pigments and socks cannot be chafed on the spray gun and when mixed in the mixer, especially in industrial scale, the pigment is deposited on the bottom and walls of the mixer, which leads to difficulties in homogenization of the composition, deterioration of its homogeneity and decrease in color density. The closest to the proposed is the composition of the coating of the back side of carbon paper containing, by weight. %: 4.5 Vaseline oil, 70 wax-montan, 10.5 paraffin, 15 white pigment 4. However, such a composition, even if there is white pigment when printing or writing, gives traces of the image, which leads to contamination of copy paper. . In addition, due to the small amount of oil in the composition, the pigments do not fray on the paint mill. The purpose of the invention is to eliminate traces of copying on copy paper. The goal is achieved by that; that the composition of the coating on the back side of carbon paper, which includes the binder — wax-montan, pigments and nonvolatile rote heater, was additionally introduced in the following ratio of components, wt. %: Wax-Montan55-90 Pigments2-12,5 Non-volatile solvent 1 -12.5 Rosin3-20. As a non-volatile solvent, the composition contains oleic acid or mineral oil. Can be used: various mineral oils, such as petrolatum, spindle, castor, etc. As pigments can be used milori, pigment red C, pigment ft cyanine blue, nHi MeHT green, pigment yellow, titanium dioxide, kaolin, talc, blanc fixes , calcium carbonate, aluminum or bronze powder and other brightly colored pigments. In addition, organic dyes can be used in the composition, such as Napyner Tindulin, methylene blue, crystal violet, fatty orange OP-45, ruby varnish SC, fatty brown OP-52 and other friendly dyes. Mixtures of Ti rMeHTOB and colorants can be used. As a wax bond, the raw wax can be used raw wax-1 (for example, for blue dyes, such as Indulin) or colorless bleached wax-montan (for white pigments and pigments that give a pale color). The coating composition of the back side of the copy paper is prepared as follows: A mixture of wax, rosin or wax, rosin and non-volatile solvent is melted while moving, and a dye or polished paste containing pigments and non-volatile solvent in a 1: 1 ratio is added to the molten mass: 2 The resulting mixture is heated on a glycerol bath at PO-120 ° C while moving 1-2 hours until the homogeneous mass is drained. -. : ... Example 1. To a pre-molten mixture of rosin (7 g) and crude waxamontan (90 g) are added oleic acid (1 g) and indulin (2 g). The resulting mixture was heated on a glycerol bath at 110 ° C for 1 hour with constant movement. The molten mass is applied to the reverse side of the copy paper. Get a copy paper coated with the reverse side of purple. When printed on a squeaking cloth, there were no traces of the short side coating on the copy paper. Example 2. Analogously to example 1, a mixture is prepared containing 5 g of rosin, 88 g of bleached, wax-m () NTane, 2 g of oleic acid and 5 g of ruby SC varnish. This composition in molten condition is applied on the reverse side of the copy paper. A red-coated back paper is obtained. When printed on a squeaking cloth, there were no traces of the short side coating on the copy paper. Example 3. 5 g of aluminum powder are transferred from 5 g of linseed oil and the mixture is ground on a paint mill 6 times. Separately, 20 g of rosin and 70 g of bleached woksc-montan are melted, and rubbed paste is added to them. The resulting mixture is heated in a glycerol bath at 120 ° C for 2 hours with constant movement and in the molten state. It is applied to the reverse side of the copy paper. A silver-coated backing paper is obtained. When printed on a squeaking cloth, no traces of pigmented backing on the copy paper were found. Example 4. 6.25 g of aluminum powder and 6.25 g of titanium dioxide are transferred from 12; 5 g of spun oil, the mixture is ground on 6 times on a spray grinder and a pre-molten mass is added containing 20 g of rosin and 55 g of bleached montana wax . Then they proceed as in example 3. Silver-white coated copy paper is obtained, which, when printed on a printing mask, leaves no traces of copying on copy paper. Example 5. Analogously to Example 3, formulations of coatings on the back side of carbon paper are prepared according to the well-known (without pigment milling) (A), as well as with rosin and wax-montan according to this invention (B) replacing 10% wax-montan with paraffin B (C) and without rosin (with a grind of pigments) (D). The data of the compositions shown in the table. Get the copy paper with a white coated back. When printing on a squeaking cloth, in case of using composition B, copying was not found, in others there are traces of copying. Example 6. Similarly to the pr 3, a composition containing 3 g of rosin, 72 g is prepared.

bleached montana wax, 12.5 g of kaolin and 12.5 g of industrial oil No. 50. The molten mixture is applied to the reverse side of the copy paper. A back coated paper is obtained which is not white.

As can be seen from the examples, the proposed coating composition of the back side of carbon paper provides the application of a pigmented MEL coating. it

the coating, unlike the known, does not copy.

Coating on the reverse side of the copy paper provides a significant economic effect by reducing the scrap rate due to the curl of the paper and the passage of paint on the reverse side. The use of this invention improves the aesthetic appearance of carbon paper and increases labor productivity when working on food machines.

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10.5-10-, 5 5 Formula of the invention

. The coating composition of the back side of copy paper, including a binder — wax-montan, pigments and a non-volatile solvent, characterized in that, in order to eliminate copy marks on copy paper, the composition additionally contains rosin with the following components, weight. %:

Wax Montan55-90

Pigments2-12,5

Non-volatile solvent 1 - 12,5 Rosin3-20.

2. The composition according to claim 1, characterized in that as a non-volatile solvent it

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contains oleic acid or mineral oil.

Sources of information taken into account in the examination

1. The patent of Germany No. 1227034, cl. 15 t 7/02 15/10, 1966.

2. The patent of Germany No. 922586, cl. 15 t7 / 02, 1955.

3. US patent number 2322367, cl. 117-36 3 1943.

4. Uetsky MI, et al. Technical paper for reproduction of documentation. M., 1973, p. 164 (prototype).

Claims (2)

Claim 1. The coating composition of the reverse side of the carbon paper, including a binder - wax-montan, pigments and a non-volatile solvent, characterized in that, in order to eliminate the traces of copying on carbon paper, the composition additionally contains rosin with the following <ratio of components, weight. %: Wax-Montan 55-90 Pigments 2-12.5 Non-volatile solvent 1-12.5 Rosin 3-20. 2. Composition by π. 1, characterized in that ⁴⁴ as a non-volatile solvent it contains oleic acid or mineral oil.