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. 22, 1991
Filed:
Mar. 23, 1990
Carlo Marchesano, Savona, IT;
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
A concentrated alkaline photographic developer composition, packaged in a single part to be diluted with water to form a ready to use developing solution for silver halide photographic materials, which comprises dihydroxybenzene developing agents, inorganic alkali agnets, inorganic antioxidant agents, sequestering agents and antifoggants, wherein said inorganic antioxidant agents comprise Na.sub.2 SO.sub.3 (sodium sulfite) and K.sub.2 SO.sub.3 (potassium sulfite) in a molecular ratio of 1:1 to 1:3 in an amount of from 1.6 to 4 moles per liter, the molecular ratio between said inorganic antioxidant agents and the developing agents is from 1.50 and 4.00, and said concentrated developer composition has a specific gravity higher than 1.300 at 20.degree. C., and a method of making a concentrated alkaline photographic developer composition, packaged in a single part to be diluted with water to form a ready to use developing solution for silver halide photographic materials, which comprises dihydroxybenzene developing agents, inorganic alkali agents, inorganic antioxidant agents, sequestering agents and antifoggants, characterized in that comprises the following steps: