Global Patent Index - EP 0263508 A3

EP 0263508 A3 19880803 - PROCESS FOR PREPARING A PHOTOGRAPHIC EMULSION CONTAINING TABULAR GRAINS EXHIBITING HIGH SPEED

Title (en)

PROCESS FOR PREPARING A PHOTOGRAPHIC EMULSION CONTAINING TABULAR GRAINS EXHIBITING HIGH SPEED

Publication

EP 0263508 A3 19880803 (EN)

Application

EP 87114626 A 19871007

Priority

US 91750586 A 19861010

Abstract (en)

[origin: EP0263508A2] Process for preparing a photographic emulsion containing tabular silver halide grains, which exhibit high speed upon sensitization, having a thickness of about 0.05 to 0.5 mu m, average grain volume of about 0.05 to 1.0 mu m<3> and mean aspect ratio of greater than 2:1 comprising A. adding silver nitrate to a vessel containing dispersing medium/bromide mixture, initial bromide ion concentration 0.08 to 0.25 N, to form tabular seed grains; B. adding an ammoniacal base solution, to achieve 0.002 to 0.2 normal of the base (e.g., after at least 2% of total silver nitrate has been added); and C. adding additional silver nitrate and halide, i.e., Br<-> or BrI<->, by balanced double jet procedure. The emulsions are used in photographic elements for x-ray, graphic arts, etc. a

IPC 1-7

G03C 1/02

IPC 8 full level

C01G 5/02 (2006.01); G03C 1/005 (2006.01); G03C 1/015 (2006.01); G03C 1/035 (2006.01)

CPC (source: EP)

G03C 1/0051 (2013.01)

Citation (search report)

  • [Y] DE 156345 C
  • [Y] DE 3241640 A1 19830519 - EASTMAN KODAK CO [US]
  • [Y] RESEARCH DISCLOSURE, no. 232, August 1983, pages 261-264, disclosure no. 23212, Havant, Hampshire, GB; "Tabular grain silver bromide emulsions, photographic elements incorporating these emulsions, and processes for their preparation and use"
  • [Y] RESEARCH DISCLOSURE, no. 225, January 1983, pages 20-58, disclosure no. 22534, Havant Hampshire, GB; "Sensitized high aspect ratio silver halide emulsions and photographic elements"

Designated contracting state (EPC)

BE CH DE FR GB IT LI LU NL SE

DOCDB simple family (publication)

EP 0263508 A2 19880413; EP 0263508 A3 19880803; EP 0263508 B1 19900411; AU 586581 B2 19890713; AU 7951287 A 19880414; BR 8705421 A 19880524; CA 1316035 C 19930413; DE 3762292 D1 19900517; DK 529087 A 19880411; DK 529087 D0 19871009; JP S63107814 A 19880512; NO 874224 D0 19871009; NO 874224 L 19880411

DOCDB simple family (application)

EP 87114626 A 19871007; AU 7951287 A 19871009; BR 8705421 A 19871009; CA 548681 A 19871006; DE 3762292 T 19871007; DK 529087 A 19871009; JP 25395587 A 19871009; NO 874224 A 19871009