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:
Nov. 23, 1993
Filed:
Sep. 30, 1992
Shigeharu Urabe, Kanagawa, JP;
Shunichi Aida, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A method of preparing a superfine grain emulsion with a grain size of 0.05 .mu.m or less is provided, which includes mixing aqueous solutions of a water-soluble silver salt and a water-soluble halide with vigorous stirring inside a closed mixing device furnished with an agitator, where the solutions are fed into the device simultaneously and continuously, in the presence of at least one of a high molecular compound and a substance capable of adsorbing to silver halide, each of which has a physical retardance value of at least 40 as determined by PAGI method, and immediately expelling the newly-formed grains from the mixing device. Another method includes mixing the aqueous solutions in a mixing device as described above, immediately expelling the newly-formed grains from the device, and mixing the expelled grains with at least one of the above-described high molecular compound and substance. The silver halide photographic materials utilizing the superfine grain emulsion are suitable for holographic image-recording and image-recording with electron beam, lasers, and so on.