US3661591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diazotype materials
Assignee: Ozalid Co Ltd
•
Filing: 1970-03-24
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Granted: 1972-05-09
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Expires: 1990-03-24
Abstract
Abstract A diazotype material for use in making copies of X-ray films which comprises a support carrying a light-sensitive layer containing at least one diazonium compound, a coupler and a nonlight-sensitive ultra-violet absorber, the ultra-violet absorber being effective in screening out radiation in the range of 3,400 to 4,000 A, being transparent to all radiation at or above 4,300 A and being present in an amount such as to give a background absorbance of at least 0.9 at 4,000 A.
Inventors
- 👤 Peter William Maurice Reed
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:36
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/52; G03C1/61; G03C1/76; G03C1/815; G03C1/8155; Y; Y10; Y10S; Y10S430/00; Y10S430/167; Y10S430/168
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
24 words
A diazotype copying material as claimed in claim 1, wherein the background absorbance at 4,000 A of the light-sensitive layer does not exceed 2.0.
Claim 2
Dependent Claim
16 words
A diazotype copying material as claimed in claim 1, wherein the support is a transparent film.
Claim 3
Dependent Claim
23 words
A copying material as claimed in claim 1, wherein the diazonium compounds are 1-diazo-4-(N,N-diethylamino) benzene fluoroborate, 1-diazo-2-ethoxy-4-(N,N-diethylamino) benzene fluoroborate and 1-diazo-2,5-diethoxy-4-morpholino benzene fluoroborate.
References Cited (Backward Citations)
US2378583A
Cited
US3525618A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |