Patent US4472485A successfully refreshed from Google Patents.
US4472485A
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Stretched composite film
Assignee: TOKUYAMA SODA A CORP OF JAPAN KK
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Filing: 1982-11-22
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Granted: 1984-09-18
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Expires: 2002-11-22
Abstract
Abstract A stretched composite film composed of a first film layer (A) of a saponified product of an ethylene/vinyl acetate copolymer, and melt-laminated respectively to both surfaces of the first film layer (A), second film layers (B) and (B') of a blend composed of an unsaturated carboxylic acid-grafted polypropylene and polypropylene, said blend having (i) an ethylene content, C2, of at most 0.6% by weight and (ii) a melt flow index, MFI, of not more than 25 g/10 minutes with (iii) the ethylene content (C2) and the melt flow index (MFI) satisfying the expression log MFI</=1.4(1-C2). The composite film optionally further comprises a third film layer (C) of a thermoplastic synthetic resin melt-laminated to the surface of one of the second film layers (B) and (B').
Inventors
- 👤 Akira Tabuse
- 👤 Michio Nakatsukasa
- 👤 Mitsuo Kamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:02
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/32; B32B27/06; B32B27/08; B32B27/30; B32B27/306; B32B2250/00; B32B2250/02; B32B2250/24; B32B2250/246; B32B2270/00; B32B2323/00; B32B2323/10; B32B2331/00; B32B2331/04; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31725; Y10T428/31739; Y10T428/31743; Y10T428/31746; Y10T428/3175; Y10T428/31786; Y10T428/31797; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31928
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
112 words
A stretched composite film composed of a first film layer (A) of a saponified product of an ethylene/vinyl acetate copolymer, and melt-laminated respectively to both surfaces of the first film layer (A), second film layers (B) and (B') of a blend composed of an unsaturated carboxylic acid-grafted polypropylene and polypropylene, said blend having (i) an ethylene content, C 2 , of at most 0.6% by weight; (ii) a melt flow index, MFI, of not more than 25 g/10 minutes; (iii) the ethylene content (C 2 ) and the melt flow index (MFI) satisfying the expression log MFI≦1.4(1-C 2 ); and (iv) a melt flow index ratio, MFIR, of not more than 12.
Claim 2
Dependent Claim
112 words
A stretched composite film composed of a first film layer (A) of a saponified product of an ethylene/vinyl acetate copolymer, and melt-laminated respectively to both surfaces of the first film layer (A), second film layers (B) and (B') of a blend composed of an unsaturated carboxylic acid-grafted polypropylene and polypropylene, said blend having (i) an ethylene content, C 2 , of at most 0.6% by weight; (ii) a melt flow index, MFI, of not more than 25 g/10 minutes; (iii) the ethylene content (C 2 ) and the melt flow index (MFI) satisfying the expression log MFI≦1.4(1-C 2 ); and (iv) a melt flow index ratio, MFIR, of not more than 12.
Claim 3
Dependent Claim
23 words
The composite film of claim 1 wherein the saponification product of ethylene/vinyl acetate copolymer has a degree of saponification of at least 90%.
Claim 4
Dependent Claim
23 words
The composite film of claim 2 wherein the saponification product of ethylene/vinyl acetate copolymer has a degree of saponification of at least 99%.
Claim 5
Dependent Claim
19 words
The composite film of claim 1 wherein the ethylene/vinyl acetate copolymer contains 15 to 50 mole% of ethylene units.
Claim 6
Dependent Claim
19 words
The composite film of claim 4 wherein the ethylene/vinyl acetate copolymer contains 20 to 40 mole% of ethylene units.
Claim 7
Dependent Claim
20 words
The composite film of claim 1 wherein the blend has an ethylene content of not more than 0.4% by weight.
Claim 8
Dependent Claim
18 words
The composite film of claim 1 wherein the blend has an MFI of 1 to 20 g/10 minutes.
Claim 9
Dependent Claim
33 words
The composite film of claim 1 wherein the blend is prepared by melt-kneading the polypropylene in an oxygen-containing gas atmosphere to decompose it and followed by blending with the unsaturated carboxylic acid-grafted polypropylene.
Claim 10
Dependent Claim
16 words
The composite film of claim 1 wherein the unsaturated carboxylic acid-grafted polypropylene is maleic anhydride-grafted polypropylene.
Claim 11
Dependent Claim
20 words
The composite film of claim 9 wherein the maleic anhydride-grafted polypropylene contains 0.01 to 15% by weight of maleic anhydride.
Claim 12
Dependent Claim
29 words
The composite film of claim 1 wherein the polypropylene in the blend of it with the unsaturated carboxylic acid-grafted polypropylene has an MFI of 0.1 to 25 g/10 minutes.
Claim 13
Dependent Claim
18 words
The composite film of claim 1 wherein the second film layers (B) and (B') further contains another polyolefin.
Claim 14
Dependent Claim
28 words
The composite film of claim 12 wherein the amount of the other polyolefin is 5 to 100 parts by weight per 100 parts by weight of the blend.
Claim 15
Dependent Claim
141 words
A stretched composite film composed of a first film layer (A) of a saponified product of an ethylene/vinyl acetate copolymer, second film layers (B) and (B') of a blend composed of an unsaturated carboxylic acid-grafted polypropylene and polypropylene melt-laminated respectively to both surfaces of the first film layer (A), and a third film layer (C) of a thermoplastic synthetic resin melt-laminated to the surface of one of the second film layers (B) and (B'), said blend in the second film layers having (i) an ethylene content, C 2 , of at most 0.6% by weight; (ii) a melt flow index, MFI, of not more than 25 g/10 minutes; (iii) the ethylene content (C 2 ) and the melt flow index (MFI) satisfying the expression log MFI≦1.3(1-C 2 ); and (iv) a melt flow index ratio, MFIR, of not more than 12.
Claim 16
Dependent Claim
141 words
A stretched composite film composed of a first film layer (A) of a saponified product of an ethylene/vinyl acetate copolymer, second film layers (B) and (B') of a blend composed of an unsaturated carboxylic acid-grafted polypropylene and polypropylene melt-laminated respectively to both surfaces of the first film layer (A), and a third film layer (C) of a thermoplastic synthetic resin melt-laminated to the surface of one of the second film layers (B) and (B'), said blend in the second film layers having (i) an ethylene content, C 2 , of at most 0.6% by weight; (ii) a melt flow index, MFI, of not more than 25 g/10 minutes; (iii) the ethylene content (C 2 ) and the melt flow index (MFI) satisfying the expression log MFI≦1.3(1-C 2 ); and (iv) a melt flow index ratio, MFIR, of not more than 12.
Claim 17
Dependent Claim
23 words
The composite film of claim 14 wherein the saponification product of ethylene/vinyl acetate copolymer has a degree of saponification of at least 90%.
Claim 18
Dependent Claim
23 words
The composite film of claim 15 wherein the saponification product of ethylene/vinyl acetate copolymer has a degree of saponification of at least 99%.
Claim 19
Dependent Claim
19 words
The composite film of claim 14 wherein the ethylene/vinyl acetate copolymer contains 15 to 50 mole% of ethylene units.
Claim 20
Dependent Claim
19 words
The composite film of claim 17 wherein the ethylene/vinyl acetate copolymer contains 20 to 40 mole% of ethylene units.
Claim 21
Dependent Claim
20 words
The composite film of claim 14 wherein the blend has an ethylene content of not more than 0.4% by weight.
Claim 22
Dependent Claim
18 words
The composite film of claim 14 wherein the blend has an MFI of 1 to 20 g/10 minutes.
Claim 23
Dependent Claim
33 words
The composite film of claim 14 wherein the blend is prepared by melt-kneading the polypropylene in an oxygen-containing gas atmosphere to decompose it and followed by blending with the unsaturated carboxylic acid-grafted polypropylene.
Claim 24
Dependent Claim
16 words
The composite film of claim 14 wherein the unsaturated carboxylic acid-grafted polypropylene is maleic anhydride-grafted polypropylene.
Claim 25
Dependent Claim
20 words
The composite film of claim 14 wherein the maleic anhydride-grafted polypropylene contains 0.01 to 15% by weight of maleic anhydride.
Claim 26
Dependent Claim
29 words
The composite film of claim 14 wherein the polypropylene in the blend of it with the unsaturated carboxylic acid-grafted polypropylene has an MFI of 0.1 to 25 g/10 minutes.
Claim 27
Dependent Claim
18 words
The composite film of claim 14 wherein the second film layers (B) and (B') further contains another polyolefin.
Claim 28
Dependent Claim
28 words
The composite film of claim 25 wherein the amount of the other polyolefin is 5 to 100 parts by weight per 100 parts by weight of the blend.
Claim 29
Dependent Claim
13 words
The composite film of claim 14 wherein the thermoplastic synthetic resin is polypropylene.
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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) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |