SU489072A1 - Stabilizing composition for single-stage process - Google Patents

Description

This is achieved by introducing into the stabilizing composition as a film-forming substance derived gelatins of the general formula, where G is the residue of gelatin; R - CO-Af-COOH, -CO-NH-At. -CO-CH "CH-COOH or - S O - A.-; Ag-aryl.

Modified at the amino group of gelatin is prepared by reacting aqueous solutions of gelatin at 40 ° C in an alkaline medium with aromatic sulfohloriaami, organic isocyanates, anhydrides and acid chlorides of carboxylic acids, vinyl sulfone, halogenopyrimidine maleilimidami and so forth dissolved in acetone or another solvent dioksake.

The gelatin modified in this way does not differ in appearance from ordinary gelatin.

The modification and properties of gelatin as a high molecular compound do not change (the viscosity of the solution, the strength of the gel, the molecular weight of the modified gelatin remain virtually unchanged).

These products, just like ordinary gelatin, are well soluble in water, but when acidified to the isoelectric state, they coagulate from an гГГвв,, причем причем причем, and the isoelectric point of the modified gelatin shifts to a more acidic region (pH 3-4).

Example 1. Two solutions are prepared for the preparation of the stabilizer.

Solution 1. 40 g of phthaloyl-gelatin with a phthalation rate of 7 to 5-95% is poured with a mixture of 400 ml of distilled water and 500 ml of ethyl alcohol, swelling takes place for at least 1 hour and then

at a temperature of 30 - 32 C dissolution.

The resulting solution is filtered through a single layer of cambric.

Solution 2. In 100 ml of distilled water, 5 g of ammonium chloride are dissolved.

In cooled solution 1, solution 2 is introduced gradually as it is added.

After filtration, the resulting stabilizing composition is poured into a glass container, where cotton swabs will prevent

15-2O minutes Photographs obtained after diffusion treatment are coated with a thin layer of a stabilizing compound using a cotton swab. Sample evaluation. produced immediately after processing as well

after three days of irradiation with an LDS - 30 lamp.

After this, densitometric measurements are made at the sites corresponding to the exposed negative spots.

(Dmu).

The test results are shown in the table.

Thus, the use of a phthaloyl nickelatin-based stabilizing solution makes it possible to ensure high preservation of photo prints and at the same time increases the colloidal stability of the stabilizer.

Example 2 A stabilizer is prepared on the basis of toluene sulfonoyl gelatin according to the formulation described in Example 1. The test procedure is the same.

A toluene sulfonoyl gelatin stabilizer provides

0.01 (before irradiation) and b

0.01

mm (after irradiation).

g

The stabilizing compound is stored for more than 12 months without coagulation. When comparing the obtained results with the characteristics of the stabilizer used on the basis of the graft polyvinyl copolymer

alcohol with methacrylic acid (see table) shows the advantage of the proposed samples.

Claims (1)

Invention Formula A stabilizing composition for a single-stage process, including a film-forming substance, characterized in that, in order to increase the colloidal stability of the stabilizing composition and to prevent the formation of color during storage of prints, gelatin derivatives of the formula are used as a film-forming substance. G-NH-R, where G is the residue of gelatin; R-CO-: r -soon, -co-mn-Ag, -co-ccd: n-soon, or - S O - Ar; AG - aryl.