Patent US4112181A successfully refreshed from Google Patents.
US4112181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing a film of vinylidene chloride polymer
Assignee: WR Grace and Co Conn
•
Filing: 1976-03-01
•
Granted: 1978-09-05
•
Expires: 1996-03-01
Abstract
Abstract A saran laminate film is produced by coextruding saran between outer plys of thermoplastic material.
Inventors
- 👤 William G. Baird, Jr.
- 👤 Stanley E. Holbrook
- 👤 Jeremy A. Platt, deceased
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:25
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B29; B29C; B29C48/00; B29C48/03; B29C48/09; B29C48/10; B29C48/14; B29C48/147; B29C48/1472; B29C48/16; B29C48/18; B29C48/21; B29C48/25; B29C48/30; B29C48/32; B29C48/335; B29C48/336; B32B27/16; B32B27/30; B32B27/304; B32B27/32; B29C2791/00; B29C2791/004; B29C2791/007; B29C2793/00; B29C2793/0063; B29C48/001; B29C48/0017; B29C48/0018; B29C48/0019; B29C48/0022; B29K; B29K2027/00; B29L; B29L2009/00; B32B38/00; B32B38/0012; B32B2038/0028; B32B2307/00; B32B2307/50; B32B2307/514; B32B2307/518; B32B2307/584; B32B2307/70; B32B2307/724; B32B2307/7242; B32B2307/7244; B32B2323/00; B32B2323/04; B32B2323/10; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/269; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/3192
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
103 words
A film combination comprising two outer plies of thermoplastic polymer and disposed therebetween a thin biaxially oriented crystalline copolymer film made of a thermoplastic copolymer of vinylidene chloride and at least one copolymerizable monomer, wherein the vinylidene chloride is at least 50% of the material in the copolymer, said film combination having been made by extruding said copolymer as a melt between melts of outer plies of thermoplastic polymer through a die, cooling and stretching to orient so as to produce a copolymer film between the outer plies, said copolymer film being substantially devoid of pinholes and scratches and having low oxygen permeability.
Claim 2
Dependent Claim
103 words
A film combination comprising two outer plies of thermoplastic polymer and disposed therebetween a thin biaxially oriented crystalline copolymer film made of a thermoplastic copolymer of vinylidene chloride and at least one copolymerizable monomer, wherein the vinylidene chloride is at least 50% of the material in the copolymer, said film combination having been made by extruding said copolymer as a melt between melts of outer plies of thermoplastic polymer through a die, cooling and stretching to orient so as to produce a copolymer film between the outer plies, said copolymer film being substantially devoid of pinholes and scratches and having low oxygen permeability.
Claim 3
Dependent Claim
19 words
The film combination of claim 1 wherein the copolymer film has an average thickness from 0.1 to 0.5 mil.
Claim 4
Dependent Claim
29 words
The film combination of claim 1 wherein said film combination is irradiated with high energy electrons to a dosage of 1 to 75 megarads after cooling but before stretching.
Claim 5
Dependent Claim
17 words
The film combination of claim 1 wherein at least one of the outer plies is a polyolefin.
Claim 6
Dependent Claim
11 words
The film combination of claim 4 wherein the polyolefin is polyethylene.
Claim 7
Dependent Claim
11 words
The film combination of claim 4 wherein the polyolefin is polypropylene.
Claim 8
Dependent Claim
146 words
A film combination comprising two plies of thermoplastic polymer and disposed therebetween a substantially unoriented crystalline copolymer film made from a thermoplastic copolymer of vinylidene chloride and at least one copolymerizable monomer wherein the vinylidene chloride is at least 50 percent of the material in the copolymer, said copolymer film having a shrinkability at 96° C of 1 to 5 percent in the transverse direction and 2 to 10 percent in the longitudinal direction, a haze of not over 7 percent, and an elongation of at least 100 percent in both the transverse and longitudinal directions, said film combination having been made by coextruding said copolymer as a melt between melts of outer plies of thermoplastic polymer through a die so as to produce a copolymer film between the outer plies, said copolymer film being substantially devoid of pinholes and scratches and having low oxygen permeability.
Claim 9
Dependent Claim
146 words
A film combination comprising two plies of thermoplastic polymer and disposed therebetween a substantially unoriented crystalline copolymer film made from a thermoplastic copolymer of vinylidene chloride and at least one copolymerizable monomer wherein the vinylidene chloride is at least 50 percent of the material in the copolymer, said copolymer film having a shrinkability at 96° C of 1 to 5 percent in the transverse direction and 2 to 10 percent in the longitudinal direction, a haze of not over 7 percent, and an elongation of at least 100 percent in both the transverse and longitudinal directions, said film combination having been made by coextruding said copolymer as a melt between melts of outer plies of thermoplastic polymer through a die so as to produce a copolymer film between the outer plies, said copolymer film being substantially devoid of pinholes and scratches and having low oxygen permeability.
Claim 10
Dependent Claim
25 words
The film combination of claim 7 wherein said film combination has been irradiated with high energy electrons to a dosage of 1 to 75 megarads.
References Cited (Backward Citations)
US3821182A
Cited
US3982986A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-04 | 1982-03-06 | 1982-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-04 | 1986-03-06 | 1986-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-04 | 1990-03-06 | 1990-09-05 | $7700.00 | Window Closed / Lapsed |