CS255258B1 - Light-sensitive material for diazography - Google Patents

Abstract

Light sensitive material for diazography which is common in diazography substances contain cyclic ketones, their derivatives or autocondensation products, which increase the absorption maxima induced azo dyes. A diazographle assembly is applied on paper pads or pads cellulose derivatives or polymeric support. It is used throughout the industry for information system.

Description

The invention relates to a photosensitive material for diazography. The material is intended for making copies of originals either by contact copying in the case of transparent originals or optical transmission. The visualization of the image is performed by developing in a special diazographic developer with a neutral or acidic reaction in the case of one-component materials or ammonia vapors in two-component materials.

Diazography is a well known process for a long time. The principle is based on the photolytic decomposition of aromatic diazo compounds by actinic light, where actinic light means the ultraviolet region of the spectrum, and the subsequent chemical reaction - by coupling - of the decomposed diazo compound with the passive coupling component to form an azobrave. In the case of mono-component materials, the functional light-sensitive layer contains, in addition to the excipients, only the diazo compound and the coupling substance is contained in a special diazographic developer, which is applied to the functional light-sensitive layer after exposure.

In the case of two-component materials, a color-forming coupling component selected according to the desired azo image color or coupling rate with the diazo compound used is also included in the layer applied to the substrate.

A light sensitive diazography material has now been found in which the diazographic assembly comprises stabilizing acids, stabilizing agents, diazo compounds derived from simple or substituted p-phenylenediamine derivatives, single or substituted diphenylamines, single or substituted mercaptobenzenediazo derivatives used either alone or in mixtures. Furthermore, in the case of two-component materials, it contains color-forming coupling substances which, in the case of mono-component materials, are not present in the layer and are present in the developer. Furthermore, in addition to the diazography of conventional materials, metallizing antihalation, surface-active, optical bleaches, binders in the case of materials on polymeric substrates, etc., it contains cyclic ketone compounds or derivatives thereof or self-condensation products. The coupling dyeing reaction occurring in the presence of these cyclic ketones or derivatives thereof causes an increase in the absorption intensity induced by the azo dye.

However, the reaction of these substances with diazo compounds or their photolysis products do not give color compounds. However, the absorption maximum of the azo dye increases at the same wavelength.

This applies not only to monochrome azo dyes, but also to mixed azo dyes in the case of, for example, black tones where a mixture of different coupling components is used.

The addition of cyclic ketones, their derivatives or auto-condensation products to the diazographic assembly is advantageous for both single- and two-component materials on paper substrates, as well as on cellulose derivative substrates or polymeric substrates of ester, olefinic, carbonate and other types. It is preferable to deposit such a diazographic assembly on substrates with auxiliary layers that optimize physico-mechanical properties such as torsion, penetration, adhesion and the like, optionally the diazographic assembly may be modified with fillers, polymer dispersions, etc.

Of the cyclic ketones, derivatives thereof or self-condensation products, cyclohexanone or derivatives thereof substituted with C 1 -C 3 alkyl groups are preferably used.

Example 1 (one component material) water 400 ml citric acid 10 g thiourea. 3 g aluminum sulphate 2 g

4-Diazo-2,5-dibutoxyphenylmorpholine sulfate 10 g cyclohexanone 20 g

The material is dried after being spilled on paper. Invoked in an alkaline-type diazographic developer, the black color of the drawing is obtained. _/

Example 2 (one-component material) water 500 ml citric acid 15 g aluminum sulfate 2 g 2,7-naphthalenedisulfonic acid 8 g. 4-Diazo-1-tolylmercapto-2,5-diethoxybenzene. 1/2 ZnCl ₂ 10 g cyclohexanone 30 ml

After being applied to the paper and developed in developer at pH 6-7, a black copy color is obtained.

Example 3 (one component material) water 500 ml citric acid 12 g tartaric acid 3 g 1,3,6 trisulfonic acid (sodium salt, 8 g aluminum sulphate 2.5 g

4-Diazo-1-tolylmercapto-2,5-diethoxybenzene. 1/2 ZnCl ₂ 2 g

4-diethylamino-3- (4'-chlorophenoxy) -6-chlorobenzenediazonium chloride. ZnCl ₂ 10 g cyclohexanone 20 g

Working procedure as in Example 2.

Example 4 (two-component material)

water 500 ml citric acid 13 g caffeine 5 g 4-bromo-3,5-dihydroxibenzoic acid methylamide 5 g thiourea. 10 g of zinc chloride 5 g of 4-diazo-2,5-dimethoxyphenyl morpholine. ZnCl ₂ ⁶ 9 cyclohexanone 30 g

After pouring onto paper and drying, the development after exposure is performed in ammonia vapors. The color of the developed azobravo is red.

Example 5 (two-component material)

acetone 400 9 methanol 400 9 2-methoxyethanol 50 9 citric acid 20 May 9 boric acid 10 9 p-toluenesulfonic acid 5 9 cellulose acetopropionate 30 9

2,3-dihydroxynaphthalene 15 g

4-diazo-2,5-dimethoxyphenylmorpholine. BF ₄ 15 g cyclohexanone 50 g

The coating is applied to an adhesive-treated polyester backing or to a cellulose triaxetate backing and dried. Visualization of the image is done by developing in ammonia vapors, the drawing is blue.

Claims (3)

SUBJECT OF THE INVENTION 1. A photosensitive diazography material, characterized in that the basic diazographic kit comprises stabilizing acids, counter-agents, diazo compounds derived from simple or substituted p-phenylenediamine derivatives, single or substituted diphenylamines or single or substituted mercaptobenzenediazo compounds, cyclic ketones with a maximum of 10 carbon ketones or an alkyl derivative thereof, wherein the alkyl substituent has 1 to 3 carbon atoms, or their autocondensation products to increase the absorption maximum induced by the azo dye. 2. The photosensitive material according to claim 1, characterized in that, in the case of the two-component, ammonia-induced types, the diazographic assembly comprises color-forming coupling agents which are used in a ratio of 0.3: 1 to 3: 1 relative to each other. 3. The photosensitive material according to claim 1 and 2, characterized in that it comprises a paper backing or substrates of cellulose derivatives or a backing of the polyester, polyolefinic or polycarbonate type. Severography, n. P., MOST