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| 9-119334 | May 1997 | JPX |
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| 3865591 | Katz | Feb 1975 | |
| 4427762 | Takahashi et al. | Jan 1984 | |
| 4816384 | Fruge et al. | Mar 1989 | |
| 5460919 | Obi et al. | Oct 1995 | |
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| 5834171 | Suzuki et al. | Nov 1998 |
| Number | Date | Country |
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| 0 082 015 | Jun 1983 | EPX |
| 0 785 467 A1 | Jul 1997 | EPX |
| 0 795 782 A2 | Sep 1997 | EPX |
| 2 290 625 | Jan 1996 | GBX |
| Entry |
|---|
| Research Disclosure, "An Ascorbic Acid Developer in Various Photographic Applications" (1995) Mar., pp. 185-224, No. 371. |
| Derwent Publications Ltd., Section Ch, Week 9741, An 97-439545 XP002075521 of JP 09 197 629 A. |