US3891598A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bubble-free, high barrier vinylidene chloride polymer films and process of preparation
Assignee: Dow Chemical Co
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Filing: 1974-02-11
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Granted: 1975-06-24
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Expires: 1994-02-11
Abstract
Abstract This invention is directed to improved bubble-free, high barrier film materials prepared from substantially plasticizer-free vinylidene chloride polymer compositions containing small amounts of magnesium oxide; and to a process for the preparation of such improved films.
Inventors
- 👤 Richard T Marzolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:57
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
32 words
AN IMPROVED PROCESS FOR PREPARING EXTRUDED VINYLIDENE CHLORIDE POLYMER FILM CONTAINING MODIFYING AMOUNTS OF AN ETHYLENE-VINYL ACETATE COPOLYMER, SAID FILM BEING SUBSTANTIALLY FREE FROM BUBBLES, HOLES AND WHITE SPECKS WHICN PROCESS COMPRISES
Claim 2
Dependent Claim
32 words
AN IMPROVED PROCESS FOR PREPARING EXTRUDED VINYLIDENE CHLORIDE POLYMER FILM CONTAINING MODIFYING AMOUNTS OF AN ETHYLENE-VINYL ACETATE COPOLYMER, SAID FILM BEING SUBSTANTIALLY FREE FROM BUBBLES, HOLES AND WHITE SPECKS WHICN PROCESS COMPRISES
Claim 3
Dependent Claim
125 words
PREPARING A BLEND OF (S) A DRY, POWDERED, NONPLASTICIZED NORMALLY CRYSTALLINE VINYLIDENE CHLORIDE POLYMER CONTAINING FROM ABOUT 70 TO ABOUT 95 PERCENT BY WEIGHT OF VINYLIDENE CHLORIDE INTERPOLYMERIZED WITH FROM ABOUT 30 TO ABOUT 5 PERCENT BY WEIGHT OF AT LEAST ONE MONOETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE WITH VINYLIDENE CHLORIDE, WITH (D) FROM ABOUT 0.05 TO ABOUT 1 PERCENT BASED ON POLYME WEIGHT OF MAGNESIUM OXIDE HAVING AN AVERAGE PARTICLE SIZE OF LESS THAN ABOUT 0.5 MICRON AND WHEREIN SAID BLEND IS PREPARED BY INTRODUCING SAID MAGNESIUM OXIDE BENEATH THE SURFACE OF THE MASS OF DRY VINYLIDENE CHLORIDE POLYMER PARTICLES WHILE SAID PARTICLES ARE MAINTAINED IN MOTION AND WHERE SAID MAGNESIUM OXIDE COATS SAID PARTICLES PRIOR TO CONTACT OF SAID MAGNESIUM OXIDE WITH A METAL SURFACE,
Claim 4
Dependent Claim
125 words
PREPARING A BLEND OF (S) A DRY, POWDERED, NONPLASTICIZED NORMALLY CRYSTALLINE VINYLIDENE CHLORIDE POLYMER CONTAINING FROM ABOUT 70 TO ABOUT 95 PERCENT BY WEIGHT OF VINYLIDENE CHLORIDE INTERPOLYMERIZED WITH FROM ABOUT 30 TO ABOUT 5 PERCENT BY WEIGHT OF AT LEAST ONE MONOETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE WITH VINYLIDENE CHLORIDE, WITH (D) FROM ABOUT 0.05 TO ABOUT 1 PERCENT BASED ON POLYME WEIGHT OF MAGNESIUM OXIDE HAVING AN AVERAGE PARTICLE SIZE OF LESS THAN ABOUT 0.5 MICRON AND WHEREIN SAID BLEND IS PREPARED BY INTRODUCING SAID MAGNESIUM OXIDE BENEATH THE SURFACE OF THE MASS OF DRY VINYLIDENE CHLORIDE POLYMER PARTICLES WHILE SAID PARTICLES ARE MAINTAINED IN MOTION AND WHERE SAID MAGNESIUM OXIDE COATS SAID PARTICLES PRIOR TO CONTACT OF SAID MAGNESIUM OXIDE WITH A METAL SURFACE,
Claim 5
Dependent Claim
16 words
REMOVING FROM SAID BLEND ANY AGGLOMERATE HAVING A DIAMETER IN EXCESS OF ABOUT 500 MICRONS, THEN
Claim 6
Dependent Claim
16 words
REMOVING FROM SAID BLEND ANY AGGLOMERATE HAVING A DIAMETER IN EXCESS OF ABOUT 500 MICRONS, THEN
Claim 7
Dependent Claim
16 words
removing from said blend any agglomerate having a diameter in excess of about 500 microns, then
Claim 8
Dependent Claim
16 words
removing from said blend any agglomerate having a diameter in excess of about 500 microns, then
Claim 9
Dependent Claim
21 words
The process of claim 1 wherein said normally crystalline vinylidene chloride polymer is a copolymer of vinylidene chloride and vinyl chloride.
Claim 10
Dependent Claim
22 words
admixing said blend with said ethylene-vinyl acetate copolymer in an extruder which is used to thermally fabricate the admixture into film form.
Claim 11
Dependent Claim
22 words
admixing said blend with said ethylene-vinyl acetate copolymer in an extruder which is used to thermally fabricate the admixture into film form.
Claim 12
Dependent Claim
26 words
The process of claim 2 wherein said polymer is a copolymer of about 85 percent by weight vinylidene chloride and 15 percent by weight vinyl chloride.
Claim 13
Dependent Claim
22 words
ADMIXING SAID BLEND WITH SAID ETHYLENE-VINYL ACETATE COPOLYMER IN AN EXTRUDER WHICH IS USED TO THERMALLY FABRICATE THE ADMIXTURE INTO FILM FORM.
Claim 14
Dependent Claim
22 words
ADMIXING SAID BLEND WITH SAID ETHYLENE-VINYL ACETATE COPOLYMER IN AN EXTRUDER WHICH IS USED TO THERMALLY FABRICATE THE ADMIXTURE INTO FILM FORM.
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) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |