Patent US4797354A successfully refreshed from Google Patents.
US4797354A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver halide emulsions comprising hexagonal monodisperse tabular silver halide grains
Assignee: Fujifilm Holdings Corp
•
Filing: 1987-03-06
•
Granted: 1989-01-10
•
Expires: 2007-03-06
Abstract
Abstract A silver halide emulsion is described comprising a dispersion medium and silver halide grains, wherein the projected area of hexagonal tabular silver halide grains having as the outer surfaces two parallel hexagonal planes having a ratio of the longest edge length to the shortest edge length (referred to as the adjacent edge ratio) of 2/1 or less accounts for at least 70% of the projected area of the whole silver halide grains, and further the hexagonal tabular silver halide grains are monodisperse grains. The process of production of the silver halide emulsions is also described.
Inventors
- 👤 Mitsuo Saitou
- 👤 Shigeharu Urabe
- 👤 Katsuhisa Ozeki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:44
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/0051; G03C1/035; G03C1/485; G03C1/015; G03C2001/0156; G03C2001/03535; G03C2001/03558; G03C2001/0357
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
80 words
A silver halide emulsion comprising a dispersion medium and silver halide grains, wherein the projected area of hexagonal tabular silver halide grains having as the basal planes having an adjacent edge ratio of 2/1 to 1/1 accounts for from 70% to 100% of the projected area of the whole silver halide grains, and further said hexagonal tabular silver halide grains are monodisperse grains wherein the average aspect ratio of the hexagonal tabular silver halide grains is from 2.5/1 to 20/1.
Claim 2
Dependent Claim
80 words
A silver halide emulsion comprising a dispersion medium and silver halide grains, wherein the projected area of hexagonal tabular silver halide grains having as the basal planes having an adjacent edge ratio of 2/1 to 1/1 accounts for from 70% to 100% of the projected area of the whole silver halide grains, and further said hexagonal tabular silver halide grains are monodisperse grains wherein the average aspect ratio of the hexagonal tabular silver halide grains is from 2.5/1 to 20/1.
Claim 3
Dependent Claim
18 words
A silver halide emulsion as in claim 1, wherein the adjacent edge ratio is from 1.0/1 to 1.5/1.
Claim 4
Dependent Claim
46 words
A silver halide emulsion as in claim 1, wherein the projected area of hexagonal tabular silver halide grains having two basal planes having the adjacent edge ratio of 2/1 to 1/1 accounts for at least 90% of the projected areas of the whole silver halide grains.
Claim 5
Dependent Claim
27 words
A silver halide emulsion as in claim 1, wherein the coefficient of variation of the sizes of the hexagonal tabular silver halide grains is 1 to 20%.
Claim 6
Dependent Claim
27 words
A silver halide emulsion as in claim 1, wherein the coefficient of variation of the sizes of the hexagonal tabular silver halide grains is at most 15%.
Claim 7
Dependent Claim
19 words
A silver halide emulsion as in claim 1, wherein the hexagonal tabular silver halide grains have a core/shell structure.
Claim 8
Dependent Claim
23 words
A silver halide emulsion as in claim 6, wherein the halogen composition differs between the core and the shell in the core/shell structure.
Claim 9
Dependent Claim
20 words
A silver halide emulsion as in claim 1, wherein the silver halide grain is of an internal latent image type.
References Cited (Backward Citations)
US4067739A
Cited
US4150994A
Cited
US4184877A
Cited
US4184878A
Cited
US4301241A
Cited
US4433048A
Cited
US4434226A
Cited
US4439520A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-01-10 | 1992-07-11 | 1993-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-10 | 1996-07-11 | 1997-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-10 | 2000-07-11 | 2001-01-10 | $7700.00 | Window Closed / Lapsed |