US4346834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoplastic carrying bag with polyolefin resin blend
Assignee: Pactiv LLC
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Filing: 1980-11-18
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Granted: 1982-08-31
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Expires: 2000-11-18
Abstract
Abstract According to the present invention, it has been found that blended polyolefin resins containing linear low density polyethylene copolymers (LLDPE) are advantageous in the manufacturing of thermoplastic films and bags. The blended polyolefin resins are particularly well suited for making seamless-wall handled strap bags from thin tubular film consisting essentially of a homogeneous blend of HDPE, LLDPE, and ordinary branched LDPE. Superior physical properties of blown film from this blend permits the fabrication of economical carrying bags from thinner film, resulting in substantial material savings.
Inventors
- 👤 Ranjit Mazumdar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:14
CPC Classifications
B; B65; B65D; B65D31/00; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1334; Y10T428/1345; Y10T428/24; Y10T428/24628; Y10T428/24669; Y10T428/24686; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
106 words
A thermoplastic polyolefin film having heat sealing properties and comprising a blend of (a) 5 to 20 weight % high density copolymer of ethylene with about 1 to 10 weight % alpha-olefin having 6 to 8 carbon atoms (HDPE), and having a melt index of 0.2 to 2; (b) 20 to 70 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 12 carbon atoms (LLDPE), and having a melt index of 0.2 to 2; and (c) 20 to 70 weight % highly branched low density ethylene homopolymer (LDPE) having a fractional melt index of 0.5 to 0.9.
Claim 2
Dependent Claim
106 words
A thermoplastic polyolefin film having heat sealing properties and comprising a blend of (a) 5 to 20 weight % high density copolymer of ethylene with about 1 to 10 weight % alpha-olefin having 6 to 8 carbon atoms (HDPE), and having a melt index of 0.2 to 2; (b) 20 to 70 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 12 carbon atoms (LLDPE), and having a melt index of 0.2 to 2; and (c) 20 to 70 weight % highly branched low density ethylene homopolymer (LDPE) having a fractional melt index of 0.5 to 0.9.
Claim 3
Dependent Claim
17 words
The thermo-plastic polyolefin film of claim 1 in which the HDPE comprises 10 to 15 weight percent.
Claim 4
Dependent Claim
18 words
The polyolefin film of claim 1 wherein the alpha-olefin in said LLDPE has 4 to 8 carbon atoms.
Claim 5
Dependent Claim
27 words
The film of claim 1 having a substantially uniform thickness of 20 to 40 microns, and an average polymer blend density of about 0.92 to 0.935 grs/cc.
Claim 6
Dependent Claim
40 words
A thermoplastic polyolefin bag wherein a uniform tubular film of claim 1 is pleated and heat sealed to form a transverse bottom portion and sealed at opposing portions adjacent to a central cutout to form a pair of integral handles.
Claim 7
Dependent Claim
115 words
An undershirt-type handle strap carrying bag formed of a thin polyolefin film consisting of a ternary blend of 100% hydrocarbon resins, said resin blend containing: (a) 10 to 15 weight % high density copolymer of ethylene with about 1 to 10 weight % alpha-olefin having 6 to 8 carbon atoms, and having a melt index of 0.2 to 2; (b) 20 to 70 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 8 carbon atoms, and having a melt index of 0.2 to 2; and (c) 20 to 70 weight % highly branched low density ethylene homopolymer having a fractional melt index of 0.5 to 0.9.
Claim 8
Dependent Claim
115 words
An undershirt-type handle strap carrying bag formed of a thin polyolefin film consisting of a ternary blend of 100% hydrocarbon resins, said resin blend containing: (a) 10 to 15 weight % high density copolymer of ethylene with about 1 to 10 weight % alpha-olefin having 6 to 8 carbon atoms, and having a melt index of 0.2 to 2; (b) 20 to 70 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 8 carbon atoms, and having a melt index of 0.2 to 2; and (c) 20 to 70 weight % highly branched low density ethylene homopolymer having a fractional melt index of 0.5 to 0.9.
Claim 9
Dependent Claim
44 words
The bag of claim 6 wherein said hydrocarbon resin blend contains about 20 to 40 weight % linear low density copolymer having a specific gravity 0.915 to 0.94 and about 10 weight % high density ethylene/octene copolymer having a specific gravity greater than 0.94.
Claim 10
Dependent Claim
103 words
An undershirt-type handle strap carrying bag formed of a thin polyolefin film consisting of a ternary blend of hydrocarbon resins, said resin blend containing about: (a) 20 weight % high density copolymer of ethylene with with about 1 to 12 weight % alpha-olefin having 4 to 10 carbon atoms, and having a melt index of 0.2 to 2; (b) 20 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 10 carbon atoms, and having a melt index of 0.2 to 2; and (c) 60 weight % highly branched low density polyethylene homopolymer or copolymer.
Claim 11
Dependent Claim
103 words
An undershirt-type handle strap carrying bag formed of a thin polyolefin film consisting of a ternary blend of hydrocarbon resins, said resin blend containing about: (a) 20 weight % high density copolymer of ethylene with with about 1 to 12 weight % alpha-olefin having 4 to 10 carbon atoms, and having a melt index of 0.2 to 2; (b) 20 weight % linear low density copolymer of ethylene with 1 to 10 weight % alpha-olefin having 4 to 10 carbon atoms, and having a melt index of 0.2 to 2; and (c) 60 weight % highly branched low density polyethylene homopolymer or copolymer.
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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) | 1985-08-30 | 1986-03-01 | 1986-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-30 | 1990-03-01 | 1990-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-30 | 1994-03-01 | 1994-08-31 | $7700.00 | Window Closed / Lapsed |