Veb Filmfabrik Wolfen

Jorg Marx

Peter Czerney

Horst Hartmann

Fred Walkow

Heinz Mustroph

Regina Lischewski

Carmen Haessner Geb Michael

Reinhard Walter

Peter Mockel

This invention relates to a one- or two-component diazo-type material with improved light stability and duplication capabilities. This is accomplished by using compounds of the general formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 being the same or different, represent hydrogen, alkyl with 1 to 5 carbon atoms, R.sub.1 and R.sub.2 and/or R.sub.3 and R.sub.4 represent the alkyl groups necessary for completion of a 5- or 6-membered heterocyclic ring, wherein the ring may comprise a further hetero atom, such as N, O or S;

One- or two-component diazo-type material with diphenyl diamine as light

It is the purpose and object of the present invention to make better use of the emission range of light sources and to create the diazonium salts necessary for such purpose. The diazonium salts of the present invention of the general formula ##STR1## wherein Y is ##STR2## R.sub.1, R.sub.2 are equal or different and are, alkyl having 1 to 10 carbon atoms, aryl having 6 to 10 carbon atoms in a mono or polycylic ring;

Diazonium salts and a diazo-type material comprising these diazonium

This invention relates to a radiation-sensitive, silver-free recording material for direct optical recording with high sensitivity, characterized by its exceptional resistance to light and heat and large solubility. This is achieved by the fact that the recording material contains as coloring substances, azo dyestuffs of the general formula ##STR1## R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 are the same or different and are halogen, alkoxy, alkyl, acetyl, amino; R.sub.8 hydroxy, alkoxy or acetylamino. The material distinguishes itself by the different processing variations that are possible so that with a same basic type, it is possible to obtain pictures operating according to a positive principle as well as according to a negative principle.

Silver-free light-sensitive material

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Dessau, Germany

Jorg Marx