US3072624A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Saponification process for preparation of polyvinyl alcohol
Assignee: Kurashiki Rayon Co Ltd
•
Filing: 1959-12-29
•
Granted: 1963-01-08
•
Expires: 1979-12-29
Abstract
No abstract record available.
Inventors
- 👤 Akaboshi Michijiro
- 👤 Uragami Kikuji
- 👤 Fukita Eiji
- 👤 Fukai Akimasa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:51
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/12; C08J; C08J5/00; C08J5/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
191 words
A METHOD FOR THE PREPARATION OF POLYVINYL ALCOHOL BY THE SAPONIFICATION OF POLYVINYL ACETATE WHICH COMPRISES ADDING A METHANOL SOLUTION OF POLYVINYL ACETATE CONTAINING FROM ABOUT 10 TO ABOUT 70 PERCENT BY WEIGHT OF POLYVINYL ACETATE TO THE TOP OF A MIXING ZONE, FORMING SAID METHANOL SOLUTION OF POLYVINYL ACETATE INTO A THIN FILM AND PASSING SAID THIN FILM DOWNWARDLY THROUGH SAID MIXING ZONE, SIMULTANEOUSLY ADDING FROM ABOUT 0.001 TO ABOUT 0.25 MOL PERCENT BY WEIGHT OF POLYVINYL ACETATE OF AN ALKALI METAL HYDROXIDE IN A SOLVENT SELECTED FROM THE GROUP CONSISTING OF WATER AND METHANOL INTO THE TOP OF SAID MIXING ZONE, FORMING A THIN LAYER OF SAID ALKALI METAL HYDROXIDE SOLUTION, BRINGING SAID SOLUTIONS OF POLYVINYL ACETATE AND ALKALI METAL HYDROXIDE INTO CONTACT WITH EACH OTHER, MIXING AND DISPERSING THE TWO SOLUTIONS BY IMPINGING SAID SOLUTIONS ON AN INNER WALL OF SAID MIXING ZONE, FLOWING SAID SOLUTIONS DOWN INCLINED PATHS AND AGITATING SAID SOLUTIONS AS THEY MOVE DOWNWARDLY THROUGH SAID MIXING ZONE TO FORM A UNIFORM MIXTURE OF SAID SOLUTIONS, WHEREBY SAPONIFICATION OF THE POLYVINYL ACETATE IS INITIATED, WHILE THE MIXTURE IS STILL FLOWABLE PASSING SAID MIXTURE FROM THE
Claim 2
Independent Claim
191 words
A METHOD FOR THE PREPARATION OF POLYVINYL ALCOHOL BY THE SAPONIFICATION OF POLYVINYL ACETATE WHICH COMPRISES ADDING A METHANOL SOLUTION OF POLYVINYL ACETATE CONTAINING FROM ABOUT 10 TO ABOUT 70 PERCENT BY WEIGHT OF POLYVINYL ACETATE TO THE TOP OF A MIXING ZONE, FORMING SAID METHANOL SOLUTION OF POLYVINYL ACETATE INTO A THIN FILM AND PASSING SAID THIN FILM DOWNWARDLY THROUGH SAID MIXING ZONE, SIMULTANEOUSLY ADDING FROM ABOUT 0.001 TO ABOUT 0.25 MOL PERCENT BY WEIGHT OF POLYVINYL ACETATE OF AN ALKALI METAL HYDROXIDE IN A SOLVENT SELECTED FROM THE GROUP CONSISTING OF WATER AND METHANOL INTO THE TOP OF SAID MIXING ZONE, FORMING A THIN LAYER OF SAID ALKALI METAL HYDROXIDE SOLUTION, BRINGING SAID SOLUTIONS OF POLYVINYL ACETATE AND ALKALI METAL HYDROXIDE INTO CONTACT WITH EACH OTHER, MIXING AND DISPERSING THE TWO SOLUTIONS BY IMPINGING SAID SOLUTIONS ON AN INNER WALL OF SAID MIXING ZONE, FLOWING SAID SOLUTIONS DOWN INCLINED PATHS AND AGITATING SAID SOLUTIONS AS THEY MOVE DOWNWARDLY THROUGH SAID MIXING ZONE TO FORM A UNIFORM MIXTURE OF SAID SOLUTIONS, WHEREBY SAPONIFICATION OF THE POLYVINYL ACETATE IS INITIATED, WHILE THE MIXTURE IS STILL FLOWABLE PASSING SAID MIXTURE FROM THE
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) | 1966-01-07 | 1966-07-09 | 1967-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-01-07 | 1970-07-09 | 1971-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-01-07 | 1974-07-09 | 1975-01-08 | $7700.00 | Window Closed / Lapsed |