Patent US4428494A successfully refreshed from Google Patents.
US4428494A
Expired / Lapsed
US
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Easily-openable heat seal lid
Assignee: Toyo Seikan Group Holdings Ltd
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Filing: 1982-10-18
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Granted: 1984-01-31
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Expires: 2002-10-18
Abstract
Abstract Disclosed is an easily openable heat seal lid for sealing a vessel proper by forming a heat-sealed portion between the lid and the vessel proper, which comprises a laminate comprising at least an inner face member composed of a thermoplastic resin and a metal foil, wherein scores defining a portion to be opened are formed on the side inner than the portion to be heat-sealed so that the scores extend to the midway of the thickness direction of the metal foil, an opening tab is formed on the portion of the lid to be opened through a bonding fulcrum portion composed of a thermoplastic resin hot adhesive so that the push-tearing top end of the opening tab is located on the scores, and the peel strength between the opening tab and the lid in said bonding portion is at least 0.4 Kg/5 mm.
Inventors
- 👤 Kazumi Hirota
- 👤 Yotaro Tsutsumi
- 👤 Senji Itoh
- 👤 Tadahiko Katsura
- 👤 Kikuo Matsuoka
- 👤 Ichiro Hori
- 👤 Toshihiko Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:08
CPC Classifications
B; B65; B65D; B65D17/00; B65D17/28; B65D17/401; B65D17/4011
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
An easily-openable heat seal lid for sealing a vessel proper by forming a heat-sealed portion between the lid and the vessel proper, which comprises a laminate comprising at least an inner face member composed of a thermoplastic resin and a metal foil, wherein scores defining a portion to be opened are formed on the side inner than the portion to be heat-sealed so that the scores extend to the midway of the thickness direction of the metal foil, an opening tab is formed on the portion of the lid to be opened through a bonding fulcrum portion composed of a thermoplastic resin hot adhesive so that the push-tearing top end of the opening tab is located on the scores, and the peel strength between the opening tab and the lid in said bonding portion is at least 0.4 Kg/5 mm.
Claim 2
Dependent Claim
140 words
An easily-openable heat seal lid for sealing a vessel proper by forming a heat-sealed portion between the lid and the vessel proper, which comprises a laminate comprising at least an inner face member composed of a thermoplastic resin and a metal foil, wherein scores defining a portion to be opened are formed on the side inner than the portion to be heat-sealed so that the scores extend to the midway of the thickness direction of the metal foil, an opening tab is formed on the portion of the lid to be opened through a bonding fulcrum portion composed of a thermoplastic resin hot adhesive so that the push-tearing top end of the opening tab is located on the scores, and the peel strength between the opening tab and the lid in said bonding portion is at least 0.4 Kg/5 mm.
Claim 3
Dependent Claim
51 words
A heat seal lid as set forth in claim 1, wherein the heat seal inner face member is composed of a propylene resin and the inner face member is fusion-bonded to the metal foil through an acid- or acid anhydride-modified olefin resin in which the main constituent olefin monomer is propylene.
Claim 4
Dependent Claim
51 words
A heat seal lid as set forth in claim 1, wherein the heat seal inner face member is composed of a ethylene resin and the inner face member is fusion-bonded to the metal foil through an acid- or acid anhydride-modified olefin resin in which the main constituent olefin monomer is ethylene.
Claim 5
Dependent Claim
24 words
A heat seal lid as set forth in claim 1, wherein the thermoplastic resin hot adhesive is composed of a copolyester or a polyamide.
Claim 6
Dependent Claim
57 words
A heat seal lid as set forth in claim 1 or 3, wherein the opening tab and the laminate constituting the lid have a surface treatment layer and an adhesive primer layer on the sides to be bonded, respectively, and the tab and the laminate are heat-bonded to each other through said layers by the hot adhesive.
References Cited (Backward Citations)
US3632461A
Cited
US3765561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |