Patent US3878284A successfully refreshed from Google Patents.
US3878284A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Processes for making shaped articles such as filaments or films from solutions of polyglycolic acid
Assignee: Wyeth Holdings LLC
•
Filing: 1973-02-13
•
Granted: 1975-04-15
•
Expires: 1993-02-13
Abstract
Abstract This invention relates to a process for making shaped articles from certain solutions of polyglycolic acid using hexafluoroisopropyl alcohol or hexafluoroacetone sesquihydrate as solvents. The solutions are used as spinning dopes for wet or dry spinning of polyglycolic acid into shaped articles such as filaments. The solutions can also be used to cast films of polyglycolic acid.
Inventors
- 👤 Edward E Schmitt
- 👤 William J Bailey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:58
CPC Classifications
C; C08; C08L; C08L67/00; C08L67/04; D; D01; D01F; D01F6/00; D01F6/58; D01F6/62; D01F6/625
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
113 words
A PROCESS FOR PREPARING A SHAPED ARTICLE OF POLYGLYCOLIC ACID WITH COMPRISES EXTRUDING A SOLUTION COMPRISING POLYGLYCOLIC ACID, HAVING A CRYSTALLINE MELTING POINT BETWEEN ABOUT 2222* AND 235*C AND HAVING A DEGREE OF CRYSTALLINITY NOT GREATER THAN ABOUT 30 PERCENT, DISSOLVED IN HEXAFLUOROISOPROPYL ALCOHOL, IN AN AMOUNT VARYING BETWEEN 0.01 AND 30 PERCENT BY WEIGHT OF POLYGLYCOLIC ACID BASED ON THE TOTAL WEIGHT OF THE SOLUTION, THROUGH AN EXTRUSION ORIFICE AND INTO A MEDIUM SELECTED FROM THE GROUP CONSISTING OF A LIQUID COAGULATING BATH AND AN INERT STRIPPING GAS TO FOR A SHAPED ARTICLE OF POLYGLYCOLIC ACID, TREATING SAID ARTICLE TO REMOVE RESIDUAL SOLVENT, AND STRETCHING SAID ARTICLE TO ORIENT THE POLYGLYCOLIC ACID
Claim 2
Dependent Claim
113 words
A PROCESS FOR PREPARING A SHAPED ARTICLE OF POLYGLYCOLIC ACID WITH COMPRISES EXTRUDING A SOLUTION COMPRISING POLYGLYCOLIC ACID, HAVING A CRYSTALLINE MELTING POINT BETWEEN ABOUT 2222* AND 235*C AND HAVING A DEGREE OF CRYSTALLINITY NOT GREATER THAN ABOUT 30 PERCENT, DISSOLVED IN HEXAFLUOROISOPROPYL ALCOHOL, IN AN AMOUNT VARYING BETWEEN 0.01 AND 30 PERCENT BY WEIGHT OF POLYGLYCOLIC ACID BASED ON THE TOTAL WEIGHT OF THE SOLUTION, THROUGH AN EXTRUSION ORIFICE AND INTO A MEDIUM SELECTED FROM THE GROUP CONSISTING OF A LIQUID COAGULATING BATH AND AN INERT STRIPPING GAS TO FOR A SHAPED ARTICLE OF POLYGLYCOLIC ACID, TREATING SAID ARTICLE TO REMOVE RESIDUAL SOLVENT, AND STRETCHING SAID ARTICLE TO ORIENT THE POLYGLYCOLIC ACID
Claim 3
Dependent Claim
114 words
A PROCESS FOR PREPARING A SHAPED ARTICLE OF POLYGLYCOLIC ACID WHICH COMPRISES EXTRUDING A SLUTION COMPRISING POLYGLYCOLIC ACID, HAVING A CRYSTALLINE MELTING POINT BETWEEN ABOUT 222* AND 235*C AND HAVING A DEGREE OF CRYSTALLINITY NOT EXCEEDING ABOUT 75 PERCENT, DISSOLVED IN HEXAFLUOROACETONE SESQUIHYDRATE, IN AN AMOUNT VARYING BETWEEN ABOUT 0.01 AND 40 PERCENT BY WEIGHT OF SAID POLYGLYCOLIC ACID BASED ON THE TOTAL WEIGHT OF THE SOLUTION, THROUGH AN EXTRUSION ORIFICE AND INTO A MEDIUM SELECTED FROM THE GROUP CONSISTING OF A LIQUID COAGULATING BATH AND AN INERT STRIPPING GAS TO FORM A SHAPED ARTICLE OF POLYGLYCOLIC ACID, TREATING SAID ARTICLE TO REMOVE RESIDUAL SOLVENT, AND STRETCHING SAID ARTICLE TO ORIENT THE POLYGLYCOLIC ACID.
Claim 4
Dependent Claim
114 words
A PROCESS FOR PREPARING A SHAPED ARTICLE OF POLYGLYCOLIC ACID WHICH COMPRISES EXTRUDING A SLUTION COMPRISING POLYGLYCOLIC ACID, HAVING A CRYSTALLINE MELTING POINT BETWEEN ABOUT 222* AND 235*C AND HAVING A DEGREE OF CRYSTALLINITY NOT EXCEEDING ABOUT 75 PERCENT, DISSOLVED IN HEXAFLUOROACETONE SESQUIHYDRATE, IN AN AMOUNT VARYING BETWEEN ABOUT 0.01 AND 40 PERCENT BY WEIGHT OF SAID POLYGLYCOLIC ACID BASED ON THE TOTAL WEIGHT OF THE SOLUTION, THROUGH AN EXTRUSION ORIFICE AND INTO A MEDIUM SELECTED FROM THE GROUP CONSISTING OF A LIQUID COAGULATING BATH AND AN INERT STRIPPING GAS TO FORM A SHAPED ARTICLE OF POLYGLYCOLIC ACID, TREATING SAID ARTICLE TO REMOVE RESIDUAL SOLVENT, AND STRETCHING SAID ARTICLE TO ORIENT THE POLYGLYCOLIC ACID.
Claim 5
Dependent Claim
85 words
A process for preparing a cast film of polyglycolic acid which comprises depositing a solution comprising polyglycolic acid, having a crystalline melting point between about 222*C and 235*C and having a degree of crystallinity not greater than about 30 percent, dissolved in hexafluoroisopropyl alcohol, in an amount varying between 0.01 aNd 30 percent by weight of polyglycolic acid based on the total weight of the solution, on to a surface and thereupon removing said solvent to deposit a film of polyglycolic acid upon said surface.
Claim 6
Dependent Claim
85 words
A process for preparing a cast film of polyglycolic acid which comprises depositing a solution comprising polyglycolic acid, having a crystalline melting point between about 222*C and 235*C and having a degree of crystallinity not greater than about 30 percent, dissolved in hexafluoroisopropyl alcohol, in an amount varying between 0.01 aNd 30 percent by weight of polyglycolic acid based on the total weight of the solution, on to a surface and thereupon removing said solvent to deposit a film of polyglycolic acid upon said surface.
Claim 7
Dependent Claim
78 words
A process for preparing a cast film of polyglycolic acid, having a crystalline melting point between about 222* and 235*C and having a degree of crystallinity not exceeding about 75 percent, dissolved in hexafluoroacetone sesquihydrate, in an amount varying between about 0.01 and 40 percent by weight of said polyglycolic acid based on the total weight of the solution, on to a surface and thereupon removing said solvent to deposit a film of polyglycolic acid upon said surface.
Claim 8
Dependent Claim
78 words
A process for preparing a cast film of polyglycolic acid, having a crystalline melting point between about 222* and 235*C and having a degree of crystallinity not exceeding about 75 percent, dissolved in hexafluoroacetone sesquihydrate, in an amount varying between about 0.01 and 40 percent by weight of said polyglycolic acid based on the total weight of the solution, on to a surface and thereupon removing said solvent to deposit a film of polyglycolic acid upon said surface.
References Cited (Backward Citations)
US2676945A
Cited
US3227674A
Cited
US3245944A
Cited
US3297033A
Cited
US3468853A
Cited
US3435008A
Cited
US3565869A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |