US4168980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat developable photographic material and process
Assignee: Eastman Kodak Co
•
Filing: 1977-08-19
•
Granted: 1979-09-25
•
Expires: 1997-08-19
Abstract
Abstract A heat developable photographic material comprising, in reactive association, (a) photosensitive silver halide, with (b) an image-forming combination comprising (i) a silver imidazoline-2-thione wherein the imidazoline-2-thione portion is a 1-methyl, 1-ethyl or 1-phenyl-4-imidazoline-2-thione, with (ii) an organic, silver halide developing agent and (c) a binder, can provide developed and stabilized images without the need for processing solutions or baths. An image can be developed and stabilized in this material by merely heating the material to moderately elevated temperatures after imagewise exposure. Other addenda employed in heat developable photographic silver halide materials can be employed with the heat developable photographic materials described.
Inventors
- 👤 Robert A. La Rossa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:46
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/494; G03C1/498; G03C1/49809
Claims Analysis
Total Claims: 63
Claim 1
Independent Claim
102 words
In a heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, with (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, with (ii) an organic, silver halide developing agent and (c) a binder, the improvement wherein said imidazoline-2-thione portion of the silver imidazoline-2-thione is a 1-methyl, 1-ethyl or 1-phenyl-4-imidazoline-2-thione ligand wherein the ratio of said imidazoline-2-thione portion ligand to silver ion in said silver imidazoline-2-thione is at least about 1.0, and, wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 2
Dependent Claim
102 words
In a heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, with (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, with (ii) an organic, silver halide developing agent and (c) a binder, the improvement wherein said imidazoline-2-thione portion of the silver imidazoline-2-thione is a 1-methyl, 1-ethyl or 1-phenyl-4-imidazoline-2-thione ligand wherein the ratio of said imidazoline-2-thione portion ligand to silver ion in said silver imidazoline-2-thione is at least about 1.0, and, wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 3
Dependent Claim
19 words
A photographic element as in claim 1 wherein said photosensitive silver halide is a gelatino photosensitive silver halide emulsion.
Claim 4
Dependent Claim
30 words
A photographic element as in claim 1 wherein the ratio of said ligand to silver ion in said silver imidazoline-2-thione is within the range of about 1.2 to about 1.5.
Claim 5
Dependent Claim
62 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione and (ii) an organic, silver halide developing agent, and (c) a polymeric binder, and wherein the molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione is at least 1.0.
Claim 6
Dependent Claim
62 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione and (ii) an organic, silver halide developing agent, and (c) a polymeric binder, and wherein the molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione is at least 1.0.
Claim 7
Dependent Claim
18 words
A photographic element as in claim 4 wherein said developing agent is a 3-pyrazolidone silver halide developing agent.
Claim 8
Dependent Claim
14 words
A photographic element as in claim 4 wherein said binder is a gelatino binder.
Claim 9
Dependent Claim
12 words
A photographic element as in claim 4 also comprising a 3-mercapto-1,2,4-triazole antifoggant.
Claim 10
Dependent Claim
32 words
A photographic element as in claim 4 wherein the molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione is within the range of about 1.2 to about 1.5.
Claim 11
Dependent Claim
20 words
The photographic element as in claim 4 wherein said developing agent is a combination of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or isopropylhydroquinone.
Claim 12
Dependent Claim
36 words
The photographic element as in claim 4 wherein the concentration of said developing agent is within the range of about 0.25 to about 1.0 millimole of developing agent per millimole of silver ion in the element.
Claim 13
Dependent Claim
31 words
A photographic element as in claim 4 wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 14
Dependent Claim
116 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione wherein the imidazoline-2-thione portion is represented by the formula: ##STR17## and the molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione is within the range of about 1.2 to about 1.6, with (ii) an organic silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 15
Dependent Claim
116 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione wherein the imidazoline-2-thione portion is represented by the formula: ##STR17## and the molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione is within the range of about 1.2 to about 1.6, with (ii) an organic silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 16
Dependent Claim
105 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-hydroxyethyl-4-imidazoline-2-thione within the range of about 1.2 to about 1.5, and (ii) an organic silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 17
Dependent Claim
105 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-hydroxyethyl-4-imidazoline-2-thione within the range of about 1.2 to about 1.5, and (ii) an organic silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 18
Dependent Claim
101 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino, photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione within the range of about 1.2 to about 1.5, with (ii) a combination of silver halide developing agents consisting essentially of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or with isopropylhydroquinone, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 19
Dependent Claim
101 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino, photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione within the range of about 1.2 to about 1.5, with (ii) a combination of silver halide developing agents consisting essentially of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or with isopropylhydroquinone, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 20
Dependent Claim
88 words
In a heat developable photographic composition comprising (a) photosensitive silver halide, with (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, with (ii) an organic, silver halide developing agent, and (c) a binder, the improvement wherein said imidazoline-2-thione portion of the silver imidazoline-2-thione is a 1-methyl, 1-ethyl or 1-phenyl-4-imidazoline-2-thione ligand wherein the ratio of said ligand to silver ion is at least 1.0; and, wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 21
Dependent Claim
88 words
In a heat developable photographic composition comprising (a) photosensitive silver halide, with (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, with (ii) an organic, silver halide developing agent, and (c) a binder, the improvement wherein said imidazoline-2-thione portion of the silver imidazoline-2-thione is a 1-methyl, 1-ethyl or 1-phenyl-4-imidazoline-2-thione ligand wherein the ratio of said ligand to silver ion is at least 1.0; and, wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 22
Dependent Claim
19 words
A photographic composition as in claim 15 wherein said photosensitive silver halide is a gelatino photosensitive silver halide emulsion.
Claim 23
Dependent Claim
31 words
A photographic composition as in claim 15 wherein the molar ratio of said ligand to silver ion in said silver imidazoline-2-thione is within the range of about 1.2 to about 1.5.
Claim 24
Dependent Claim
55 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) an organic, silver halide developing agent, and (c) a polymeric binder, and wherein the molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione is at least 1.0.
Claim 25
Dependent Claim
55 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) an organic, silver halide developing agent, and (c) a polymeric binder, and wherein the molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione is at least 1.0.
Claim 26
Dependent Claim
18 words
A photographic composition as in claim 18 wherein said developing agent is a 3-pyrazolidone silver halide developing agent.
Claim 27
Dependent Claim
14 words
A photographic composition as in claim 18 wherein said binder is a gelatino binder.
Claim 28
Dependent Claim
15 words
A photographic composition as in claim 18 also comprising a 3-mercapto-1,2,4-triazole antifoggant and toning agent.
Claim 29
Dependent Claim
30 words
A photographic composition as in claim 18 wherein the molar ratio of the 1-methyl-4-imidazoline-2-thione portion to silver ion in said silver 1-methyl-4-imidazoline-2-thione is within the range of 1.2 to 1.5.
Claim 30
Dependent Claim
20 words
A photographic composition as in claim 18 wherein said developing agent is a combination of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or isopropylhydroquinone.
Claim 31
Dependent Claim
33 words
A photographic composition as in claim 18 wherein the concentration of said developing agent is within the range of about 0.25 to about 1.0 millimole of developing agent per millimole of silver ion.
Claim 32
Dependent Claim
31 words
A photographic composition as in claim 18 wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 33
Dependent Claim
109 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, wherein the imidazoline-2-thione portion is represented by the formula: ##STR18## and the molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione is within the range of about 1.2 to about 1.6, with (ii) an organic, silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 34
Dependent Claim
109 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver imidazoline-2-thione, wherein the imidazoline-2-thione portion is represented by the formula: ##STR18## and the molar ratio of the imidazoline-2-thione portion to silver ion in the silver imidazoline-2-thione is within the range of about 1.2 to about 1.6, with (ii) an organic, silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 35
Dependent Claim
98 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-hydroxyethyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-hydroxyethyl-4-imidazoline-2-thione within the range of about 1.2 to about 1.5, and (ii) an organic, silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 36
Dependent Claim
98 words
A heat developable photographic composition comprising (a) a gelatino photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-hydroxyethyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-hydroxyethyl-4-imidazoline-2-thione within the range of about 1.2 to about 1.5, and (ii) an organic, silver halide developing agent selected from the group consisting of 3-pyrazolidone developing agents and ascorbic acid developing agents, and (c) a gelatino binder, and wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 37
Dependent Claim
66 words
A heat developable photographic composition comprising (a) a gelatino, photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione within the range of 1.2 to 1.5, with (ii) a combination of silver halide developing agents consisting essentially of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or isopropylhydroquinone, and (c) a gelatino binder.
Claim 38
Dependent Claim
66 words
A heat developable photographic composition comprising (a) a gelatino, photosensitive silver halide emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione having a molar ratio of the imidazoline-2-thione portion to silver ion in the silver 1-methyl-4-imidazoline-2-thione within the range of 1.2 to 1.5, with (ii) a combination of silver halide developing agents consisting essentially of 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone with t-butylhydroquinone or isopropylhydroquinone, and (c) a gelatino binder.
Claim 39
Dependent Claim
38 words
A process of developing an image in a heat developable photographic element as defined in claim 1 comprising heating said element to a temperature within the range of 120° C. to 200° C. until an image is developed.
Claim 40
Dependent Claim
38 words
A process of developing an image in a heat developable photographic element as defined in claim 4 comprising heating said element to a temperature within the range of 120° C. to 200° C. until an image is developed.
Claim 41
Dependent Claim
45 words
A process of developing an image in a heat developable photographic element as defined in claim 4 comprising heating said element to a temperature within the range of 120° C. to 200° C. for about 1 to about 60 seconds until an image is developed.
Claim 42
Dependent Claim
77 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 4-imidazoline-2-thione, with (ii) a silver 1,2,4-mercaptotriazole, wherein the 1,2,4-mercaptotriazole portion is represented by the formula: ##STR19## wherein Y is aryl containing 6 to 12 carbon atoms; n is 0 to 2; and Z is hydrogen, hydroxyl or --NH 2 ; and (iii) an organic, silver halide developing agent, and (c) a binder.
Claim 43
Dependent Claim
77 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 4-imidazoline-2-thione, with (ii) a silver 1,2,4-mercaptotriazole, wherein the 1,2,4-mercaptotriazole portion is represented by the formula: ##STR19## wherein Y is aryl containing 6 to 12 carbon atoms; n is 0 to 2; and Z is hydrogen, hydroxyl or --NH 2 ; and (iii) an organic, silver halide developing agent, and (c) a binder.
Claim 44
Dependent Claim
33 words
A heat developable photographic element as in claim 32 wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 45
Dependent Claim
14 words
A photographic element as in claim 32 wherein Y is phenyl, p-methoxyphenyl or p-chlorophenyl.
Claim 46
Dependent Claim
19 words
A photographic element as in claim 32 wherein said photosensitive silver halide is a gelatino photosensitive silver halide emulsion.
Claim 47
Dependent Claim
12 words
A photographic element as in claim 32 also comprising a 3-mercapto-1,2,4-triazole antifoggant.
Claim 48
Dependent Claim
44 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent, and (c) a polymeric binder.
Claim 49
Dependent Claim
44 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent, and (c) a polymeric binder.
Claim 50
Dependent Claim
54 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino, silver bromoiodide photosensitive emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent comprising a 3-pyrazolidone silver halide developing agent, and (c) a gelatino binder.
Claim 51
Dependent Claim
54 words
A heat developable photographic element comprising a support having thereon, in reactive association, (a) a gelatino, silver bromoiodide photosensitive emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent comprising a 3-pyrazolidone silver halide developing agent, and (c) a gelatino binder.
Claim 52
Dependent Claim
70 words
A heat developable photographic composition comprising (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 4-imidazoline-2-thione, with (ii) a silver 1,2,4-mercaptotriazole wherein the 1,2,4-mercaptotriazole portion is represented by the formula: ##STR20## wherein Y is aryl containing 6 to 12 carbon atoms; n is 0 to 2; and Z is hydrogen, hydroxyl or --NH 2 ; and (iii) an organic, silver halide developing agent, and (c) a binder.
Claim 53
Dependent Claim
70 words
A heat developable photographic composition comprising (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 4-imidazoline-2-thione, with (ii) a silver 1,2,4-mercaptotriazole wherein the 1,2,4-mercaptotriazole portion is represented by the formula: ##STR20## wherein Y is aryl containing 6 to 12 carbon atoms; n is 0 to 2; and Z is hydrogen, hydroxyl or --NH 2 ; and (iii) an organic, silver halide developing agent, and (c) a binder.
Claim 54
Dependent Claim
31 words
A photographic composition as in claim 39 wherein said (a), (b) and (c) form a reaction melt at a temperature within the range of about 120° C. to about 200° C.
Claim 55
Dependent Claim
14 words
A photographic composition as in claim 39 wherein Y is phenyl, p-methoxyphenyl or p-chlorophenyl.
Claim 56
Dependent Claim
19 words
A photographic composition as in claim 39 wherein said photosensitive silver halide is a gelatino photosensitive silver halide emulsion.
Claim 57
Dependent Claim
12 words
A photographic composition as in claim 39 also comprising a 3-mercapto-1,2,4-triazole antifoggant.
Claim 58
Dependent Claim
37 words
A heat developable photographic composition comprising (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent, and (c) a polymeric binder.
Claim 59
Dependent Claim
37 words
A heat developable photographic composition comprising (a) photosensitive silver halide, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione, with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent, and (c) a polymeric binder.
Claim 60
Dependent Claim
47 words
A heat developable photographic composition comprising (a) a gelatino, silver bromoiodide photosensitive emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent comprising a 3-pyrazolidone silver halide developing agent, and (c) a gelatino binder.
Claim 61
Dependent Claim
47 words
A heat developable photographic composition comprising (a) a gelatino, silver bromoiodide photosensitive emulsion, (b) an image-forming combination comprising (i) a silver 1-methyl-4-imidazoline-2-thione with (ii) a silver 3-amino-5-benzylthio-1,2,4-triazole, and (iii) an organic, silver halide developing agent comprising a 3-pyrazolidone silver halide developing agent, and (c) a gelatino binder.
Claim 62
Dependent Claim
38 words
A process of developing an image in a heat developable photographic element as defined in claim 32 comprising heating said element to a temperature within the range of 120° C. to 200° C. until an image is developed.
Claim 63
Dependent Claim
38 words
A process of developing an image in a heat developable photographic element as defined in claim 37 comprising heating said element to a temperature within the range of 120° C. to 200° C. until an image is developed.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-24 | 1983-03-26 | 1983-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-24 | 1987-03-26 | 1987-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-24 | 1991-03-26 | 1991-09-25 | $7700.00 | Window Closed / Lapsed |