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
  • G03C1/64—Compositions containing iron compounds as photosensitive substances

Definitions

• My invention relates to light-sensitive layers sensitized with a water soluble iron salt and to v a method of making the same.
• the main object of my invention is to provide a simple, inexpensive and reliable method of making such layers.
• a further object is to produce a material in which the light-sensitive layer isprotected from premature development and damage due to mechanical abrasion.
• I form a light-sensitive layer on a. support by placing a finely-divided water-soluble light-sensitive iron salt in suspension in a solution of a water-insoluble binder in a volatile organic liquid, applying this 'dispersion' in a layer on the support and removing the organic liquid by volatilization.
• I suspend in the solution to be applied also a substance necessary for the development of the image.
• the binder of the lightsensitive layer according to the invention is water-insoluble, the formation of the coloring material necessary for the development of the image can be readily efiected by an aqueous medium provided the layer is made in a suitable thickmess.
• the use of a thin layer has the advantage that it makes it possible to obtain stronger contrasts and sharper images.
• suspensions according to the invention has the further advantage that it is possible to obtain wide variations in the concentrations and therefore one is not limited to the solubility of the image-forming substances when obtaining a concentration necessary to secure sharply-defined contrasts.
• the method according to the invention has the suspension medium advantage that it can be carried out in a simple manner and it is well adapted for use with supports of substantially water-proof material.
• Example I Example I suspension and subsequently remove the remaining solvent by'volatilization.
• Example II I form a suspension by placing 10 grs. of finelydivided brown ferric ammonium citrate, 4 grs. o'f finely-divided silver nitrate, 1 gr. of finely-divided tartaric acid, 1 gr.
• Example III I form a suspension by placing 8 grs. of a finely-divided ferric ammonium oxalate, 4 grs. of finely-divided potassium ferric citrate and 1 gr. of finely-divided oxalic acid in suspension in of finely-divided citric acid' in Example I.
• Emmple IV I form a suspension by placing 8 grs. of finelydivided green ferric ammonium citrate in suspension'in 100 cos. of ethanol in which grs. of a polymerized vinyl acetic ester, known under the trade name Vinnapaas B," is dissolved. To this suspension I add 2.5 grs. of silver nitrate and 1.5 gr. of tartaric acid. An aluminium plate is provided with a layer of the above suspension and the solvent is removed in the manner described light-sensitive material is exposed in the manner described in Example I and is then rinsed with water to obtain a grayishblack positive image from the negative.
• a layer of protective material for example Celluloid lacquer.
• supports of aluminium Although in the above examples. I have referred to the supports of aluminium, it is possible to use supports of other metallic materials which are not affected to any appreciable extent by the substances to be used, for example silver, silver-plated metals and stainless steel.
• the supports may be of other materials such as glass, acetyl cellulose, rubber, rubber derivatives such as the product known as Pliofilm which is particularly impermeableto water, paper, etc.
• cellodammar resin as the binder I may use other substances or mixtures thereof, such as polymerized hydrocarbons, for example polysterene, polymerized unsaturated fatty acid esters, derived for example from acrylic acid and its homologues, vinyl acetic acid or the like, artificial and natural resins and gums, such as ester gum, mastic and collophony.
• polymerized hydrocarbons for example polysterene
• polymerized unsaturated fatty acid esters derived for example from acrylic acid and its homologues, vinyl acetic acid or the like
• artificial and natural resins and gums such as ester gum, mastic and collophony.
• organic volatile solvents in which the above binders are generally readily soluble and which can be used in carrying out the invention I may mention substances such as benzene, toluene or the like in addition to chlorinated hydrocarbons, such as trichlorethylene and carbon tetrachloride.
• a light-sensitive material made by the method of claim 1 and comprising a support, a layer of a water-insoluble binder material adheringto a surface of said support, and a watersoluble light-sensitive iron salt in a mechanically-divided state suspended in and homogeneously distributed throughout said layer.
• a light-sensitive material made by the method of claim 1 and comprising a support of substantially water-proof material, a layer of a water-insoluble binder material adhering to a surface of said support, and a water-soluble light-sensitive iron salt in a mechanicallydivided state suspended in and homogeneously distributed throughout said layer.
• a light-sensitive material made by the method of claim 1 and comprising a support, a layer of a water-insoluble binder material adhering to a surface of said support, a watersoluble light-sensitive iron, salt, and a substance necessary for the development of the image, said salt and substance in a mechanically-divided state suspended in and being homogeneously distributed throughout said layer.
• a light-sensitive material comprising a paper support, a layer of a water-insoluble binder material adhering to a surface of said support, and a water-soluble light-sensitive iron salt in a mechanically-divided state suspended in and homogeneously distributed throughout said layer, said iron salt being readily removable from the support by agitating the material in a solvent in which the binder is soluble and the iron salt is insoluble.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Printing Plates And Materials Therefor (AREA)
• Manufacture Or Reproduction Of Printing Formes (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=7348666

Family Applications (1)

Country Status (4)

Cited By (3)

Families Citing this family (1)

• 1940
  • 1940-04-08 GB GB6348/40A patent/GB538245A/en not_active Expired
  • 1940-04-09 FR FR864723D patent/FR864723A/fr not_active Expired
  • 1940-04-11 CH CH217514D patent/CH217514A/de unknown
  • 1940-05-01 US US332847A patent/US2291130A/en not_active Expired - Lifetime

Also Published As

Similar Documents