US4302579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical brightening agents and photographic materials which contain these brightening agents
Assignee: Ilford Imaging UK Ltd
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Filing: 1980-07-24
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Granted: 1981-11-24
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Expires: 2000-07-24
Abstract
Abstract New optical brightening agents and photographic materials which contain in at least one layer these brightening agents are provided. The compounds have the general formula ##STR1## wherein R 1 and R 3 are hydrogen or methyl, R 2 and R 4 are alkyl R 5 is hydrogen, alkyl, aryl, aralkyl, X is --NH--, --O-- or --S--, L 1 and L 2 are alkylene oxide chains and M.sup.⊕ is a hydrogen or an alkali metal cation. These brightening agents enhance the brightness in the white areas of photographic print materials.
Inventors
- 👤 Graham Evans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:53
CPC Classifications
C; C07; C07D; C07D251/00; C07D251/02; C07D251/12; C07D251/26; C07D251/40; C07D251/48; C07D251/52; C07D251/42; C07D251/46; G; G03; G03C; G03C1/00; G03C1/76; G03C1/815; G03C1/8155; Y; Y10; Y10S; Y10S430/00; Y10S430/134; Y10S430/151
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
77 words
A brightening agent of the general formula ##STR12## wherein R 1 and R 3 are each hydrogen or methyl, R 2 and R 4 are alkyl having at least six carbon atoms, R 5 is hydrogen or alkyl, aryl or aralkyl, X is --NH--, --O-- or --S--, L 1 and L 2 are each alkylene oxide chains having two to 20 alkyene oxide units in the chain and M.sup.⊕ is a hydrogen or an alkylene metal cation.
Claim 2
Dependent Claim
77 words
A brightening agent of the general formula ##STR12## wherein R 1 and R 3 are each hydrogen or methyl, R 2 and R 4 are alkyl having at least six carbon atoms, R 5 is hydrogen or alkyl, aryl or aralkyl, X is --NH--, --O-- or --S--, L 1 and L 2 are each alkylene oxide chains having two to 20 alkyene oxide units in the chain and M.sup.⊕ is a hydrogen or an alkylene metal cation.
Claim 3
Dependent Claim
18 words
A brightening agent according to claim 1 wherein R 1 =R 3 and R 2 =R 4 .
Claim 4
Dependent Claim
24 words
A brightening agent according to claim 1 wherein both R 2 and R 4 have 6 to 12 carbon atoms in the alkyl chain.
Claim 5
Dependent Claim
24 words
A brightening agent according to claim 1 wherein both R 2 and R 4 have 8 or 9 carbon atoms in the alkyl chain.
Claim 6
Dependent Claim
32 words
A brightening agent according to claim 1 wherein X is --NH-- and R 5 is alkyl or aralkyl the alkyl moiety having 1 to 8 carbon atoms, or R 5 is aryl.
Claim 7
Dependent Claim
34 words
A brightening agent according to claim 1 wherein X is --NH-- and R 5 is alkyl or aralkyl the alkyl moiety having 1 to 4 carbon atoms or R 5 is naphthyl or phenyl.
Claim 8
Dependent Claim
16 words
A brightening agent according to claim 6, wherein X is --NH-- and R 5 is phenyl.
Claim 9
Dependent Claim
16 words
A brightening agent according to claim 1 wherein X is --O-- and R 5 is hydrogen.
Claim 10
Dependent Claim
27 words
A brightening agent according to claim 1 wherein L 1 and L 2 are each an ethylene oxide chain of from 2 to 16 ethylene oxide units.
Claim 11
Dependent Claim
27 words
A brightening agent according to claim 1 wherein L 1 and L 2 are each an ethylene oxide chain of from 6 to 12 ethylene oxide units.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-23 | 1985-05-25 | 1985-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-23 | 1989-05-25 | 1989-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-23 | 1993-05-25 | 1993-11-24 | $7700.00 | Window Closed / Lapsed |