The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 21, 1997
Filed:
Jul. 13, 1994
Marc Van den Zegel, Boortmeerbeek, BE;
Marcel Mestdagh, Rymenam, BE;
Agfa-Gevaert, N.V., Mortsel, BE;
Abstract
A photographic material has been coated on at least one side of a support with in at least one photosensitive layer hexagonal and/or circular tabular silver halide emulsion crystals occupying at least 70% of the total projected area of all grains, having a thickness of 0.15 to 0.30 .mu.m, a coefficient of variation of the tabular grains between 0.15 and 0.45 and an average aspect ratio of at least 2:1, prepared in the absence of ammonia by growing the nuclei, prepared at a pBr value between 1.0 and 2.0 and consuming less than 10% by weight of silver nitrate, during a first growth step at a pBr value between 1.0 and 2.5 consuming at least 10% by weight of silver nitrate and during a second growth step at a pBr value higher than 2.7 during the addition of at least 40% of the total amount of silver nitrate used. The loss in sensitivity and gradation after development of said material in a diluted cheap developer after exposing said photographic material containing said emulsion grains is neglectable in comparison with the characteristics obtained after development in stronger high quality developers.