Radiation imagery chemistry: process – composition – or product th – Radiation sensitive product – Silver compound sensitizer containing
Patent
1994-09-08
1995-05-02
Bowers, Jr., Charles L.
Radiation imagery chemistry: process, composition, or product th
Radiation sensitive product
Silver compound sensitizer containing
430567, 430607, 430613, G03C 107
Patent
active
054118530
ABSTRACT:
A grain growth process is disclosed for providing an ultrathin tabular grain emulsion in which the average equivalent circular diameter of tabular grains is increased. An aqueous dispersion is provided containing high bromide starting grains having an average thickness of less or equal to that of the ultrathin tabular grains to be produced, the dispersion having a pH in the range of from 1.5 to 8 and a limited stoichiometric excess of bromide ions. A phenol that is incapable of reducing the starting grains and that contains at least two iodo substituents is introduced into the dispersing medium as a grain growth modifier. The aqueous dispersion containing the phenol grain growth modifier is held at 40.degree. C. or a convenient higher temperature until greater than 50 percent of total grain projected area is accounted for by ultrathin tabular grains having {111} major faces of a higher average equivalent circular diameter than the starting grains and an average aspect ratio of at least 5.
REFERENCES:
patent: 3982907 (1976-09-01), Pollet et al.
patent: 4399215 (1983-08-01), Wey
patent: 4400463 (1983-08-01), Maskasky
patent: 4713323 (1987-12-01), Maskasky
patent: 4914014 (1990-04-01), Daubendiek et al.
patent: 5217858 (1993-06-01), Maskasky
patent: 5250403 (1993-10-01), Antoniades et al.
Bowers Jr. Charles L.
Eastman Kodak Company
Huff Mark F.
Thomas Carl O.
LandOfFree
Grain growth process for the preparation of high bromide ultrath does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Grain growth process for the preparation of high bromide ultrath, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Grain growth process for the preparation of high bromide ultrath will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1136004