iiiiiij ...
US005457012A
United States Patent [19] [ill Patent Number: 5,457,012
Nair et al. [45] Date of Patent: Oct. 10,1995
[54] TRANSPARENT FILM-FORMING AQUEOUS COMPOSITIONS FOR MAGNETIC RECORDING
[75] Inventors: Mridula Nair, Penfield; George L.
Oltean, Rochester, both of N.Y.
[73] Assignee: Eastman Kodak Company, Rochester, N.Y.
[21] Appl. No.: 229,267
[22] Filed: Apr. 18,1994
[51] Int. CI.6 G03C 1/76
[52] U.S. CI 430/495; 430/496; 430/501;
430/523; 430/140; 428/694 B; 428/694 BN; 428/694 BA; 252/62.51; 252/363.5
[58] Field of Search 430/495, 496,
430/501, 523, 140; 428/694 B, 694 BN, 694 BA; 252/62.51, 363.5
[56] References Cited
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FOREIGN PATENT DOCUMENTS
686172 5/1964 Canada 352/33
0467300 1/1992 European Pat. Off. 430/379
62/054146 11/1987 Japan.
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86/04719 8/1986 WIPO .
Primary Examiner—Charles L. Bowers, Jr.
Assistant Examiner—Mark F. Huff
Attorney, Agent, or Firm—Andrew J. Anderson
[57] ABSTRACT
A stable aqueous dispersion of magnetic particles contains a dispersant havingan HLB number of at least 8. The dispersion is prepared by milling an aqueous slurry of magnetic particles until there are substantially no agglomerates of magnetic particles present. The dispersion can be used to prepare magnetic recording elements and, in particular, photographic elements having a transparent magnetic recording layer.
22 Claims, 3 Drawing Sheets
