Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/04—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with macromolecular additives; with layer-forming substances
  • G03C1/047—Proteins, e.g. gelatine derivatives; Hydrolysis or extraction products of proteins

Definitions

• This "invention relates to'tli' remo'val'of DhOtO- graphically active ingredients front gelatin" or other proteins by treating the gelatifi' or other proteins with certain metals in finely divided form.
• Photographic en nilsio'ns' are ordinarily prepared by incorporating a photo-sensitive silver saltin-gelatinin aqueous solution as the protective coatin for the photosensitive Silver Salt.
• A's gelatin is a material which is obtained-from natural sources, there is oftentimes oonsieerame variation in the pro ertiesor that material when used photographically-.-' For instance, some types of" gelatin have therein 91- considerable proportion-of'photogiaphically active ingredients; Because of this-variation it has-heretofore been diflicu-lt to'prepar phot ogra hio emulsion or uniform properties following a 'setfor'mula'for their preparatiom
• One object of our invention is to provide a method for treating gelatin or other proteins whereby a considerable proportion of'the photographically active ingredients thereof are re moved or renderedinactiv'e: Another object of our invention is tdprovide" a method for new iii'g
• the gelatin be in liquid form, ordinarily the operation Will be carried out at a temperature within the range of 30-75 C. Ordinarily, the most convenient procedure is to dissolve the protein in an inert solvent and contact the metal particles therewith. Where the protein is water-soluble as in the case oi gelatin, albumin, etc., the use of an aqueous dissolving liquid is desirable. If desired, however, non-aqueous solvents may be used; for instance, gelatin may be dissolved in formamide and treated with the finely divided metal.
• Gelatins and other proteins vary among themselves as to the degree of photographic activity which is present therein; Accordingly ⁇ - some proteins will nee'd tb be treated for Monger time and with a greater amount of metal per iiiiit weight of protein than-will other rotease ving lesspho'tog'raphic activity.
• the gelatins or otherproteihs having a highd gree of photographic activity; the use of inetil inanarnount' which will not render the photographically active ingredients entirely inactive vvfl lat least reduce the photographic activity or the gelatin, if only aparti'al reduction inactivity is desired.
• Our invention' is' adapted to the treatment of various types of' gelatin; 7 For instance, hydroly'ze'd .gelatin's may be treated in accordance with our invention to inactivate onotog'rapm c'a'lly active materials therein as Well as gclatin's which have not been subjectedto hydrolysisan'd which nave-not been subjecte'd to any degrading treatment.
• Our invention is also adapt ed to the treatment of proteins generally, if desirable, to inactivate the 'photographically"active materials which are present therein; For instance, casein," zein, albimnen, soy bean protein or the like may be treated With'afinely divided metal in accordance with our'inv'ention, I v
• the metals which are employed to treat gelatin in accordance with our invention should be in a condition in which a large amount of surface is exposed which is ordinarily in a finely divided condition. If the process is operated by incorporating the finely divided metal into the gelatin solution, it is ordinarily desirable to obtain the best results that the particle size of the metal be at least 150-mesh or smaller although in some cases a larger particle size may be desirable.
• the materials which are suitable for use in our process are those, the sulfides of which, are insoluble in. water and which will not adversely affect a photographic emulsion.
• the metals which are not suitable are those the sulfides of which are soluble in water or which hydrolyze rapidly in water solution or which have a derogatory effect upon photographic emulsions.
• Some of the metals which in finely divided form are adapted for use in our process are platinum, nickel, cobalt, cadmium, and silver.
• One of the finely divided metals which we have found to be particularly suitable in processes in accordance with our invention is Raney nickel which is a well-recognized catalytic material.
• Another finely divided material which is useful is Adams catalyst, which is finely divided platinum prepared by reducing platinum oxide, also a wellknown catalytic material.
• Example 1 --1 g. of Raney nickel were stirred into a 12% aqueous gelatin solution made up using 1 pound of dry gelatin. The stirring was continued for hour at 40 C. The solid materials were then removed from the gelatin by filtering through a Kiefer press. The resulting solution was chilled, dried down, and was found to be useful for photographic emulsions, and the photographically active ingredients of that gelatin had been rendered inactive or removed as indicated by the loss in developed silver density of the emulsion made with the treated gelatin as compared to that of the untreated gelatin.
• Example 2 The procedure of Example 1 was repeated with each of the following metals in finely divided form: cobalt, platinum, lead and ordinary nickel. The gelatin which was obtained in each case was found to be useful for photographic emulsions and the photographically active ingredients thereof had been inactivated.
• a method of treating a protein having inherent photographically active ingredients therein to render those photographically active ingredients inactive which comprises treating the protein while in solution with a finely divided metal selected from the group consisting of platinum,
• nickel, cobalt, lead, cadmium, and silver followed by removing the metal particles and any reaction products thereof from the protein.
• a method of treating gelatin having inherent photographically active ingredients therein to render those photographically active ingredients inactive which comprises treating the gelatin while in solution with a finely divided metal selected from the group consisting of platinum, nickel, cobalt, lead, cadmium, and silver, followed by removing the metal particles and any reaction products thereof from the protein solution.
• a method of treating gelatin having inherent photographically active ingredients therein to render those photographically active ingredients inactive which comprises treating an aqueous solution of the gelatin with a finely divided metal selected from the group consisting of platinum, nickel, cobalt, lead, cadmium, and silver, followed by removing the metal particles and any reaction products thereof from the gelatin solution.
• a method of treating gelatin having inherent photographically active ingredients therein to render those ingredients inactive which comprises treating a solution of gelatin having a pH within the range of 4-9 with a finely divided metal selected from the group consisting of platinum, nickel, cobalt, lead, cadmium, and silver, followed by removing the metal particles and any reaction products thereof from the gelatin.
• a method of treating gelatin having inherent photographically active ingredients therein to render those ingredients inactive which comprises treating an aqueous solution of the gelatin with finely divided Raney nickel, followed by removing the Raney nickel and any reaction prod ucts thereof from the gelatin by filtering.
• A. method of treating gelatin having inherent photographically active ingredients therein to render those ingredients inactive which comprises treating an aqueous solution of the gelatin with finely divided platinum, followed by remov ing the platinum and any reaction products thereof from the gelatin solution by filtering.
• a method of treating gelatin having inher ent photographically active ingredients therein to render those ingredients inactive which comprises dissolving the gelatin in water, treating the gelatin for a time with finely divided Raney nickel, and then separating the Raney nickel and any reaction products thereof from the gelatin.

Landscapes

• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• General Physics & Mathematics (AREA)
• Medicinal Preparation (AREA)
• Peptides Or Proteins (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24800031

Family Applications (1)

Country Status (3)

Cited By (3)

• 0
  • BE BE475968D patent/BE475968A/xx unknown
• 1946
  • 1946-09-14 US US697156A patent/US2449980A/en not_active Expired - Lifetime
• 1947
  • 1947-09-11 FR FR966006D patent/FR966006A/fr not_active Expired

Non-Patent Citations (1)

Also Published As

Similar Documents