Cushioning material

• US 5,196,254 A
• Filed: 06/05/1989
• Issued: 03/23/1993
• Est. Priority Date: 07/25/1986
• Status: Expired due to Term

• Current Assignee: Sealed Air Corporation (Sealed Air)
• Original Assignee: JSP Corporation (Mitsubishi Electric Corporation)
• Inventors: Akiyama, Hiroyuki
• Primary Examiner(s): Loney, Donald J.
• Application Number:
  US07/361,562
• Time in Patent Office: 1,387 Days
• Field of Search: 428/178, 428/69, 428/72, 428/36, 428/76, 428/122, 428/315.5, 428/476.1, 428/172, 428/426.9, 428/474.4, 428/476.3, 428/188, 428/179, 428/156, 428/166, 428/174, 493/967, 493/968
• US Class Current: 428/178
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/34 comprising polyamides
• CPC Class Codes: B32B 3/28 characterised by a layer comprising a deformed thin sheet , i.e. the layer having its entire thickness deformed out of the plane, e.g. corrugated, crumpled B32B29/08 takes precedence
• CPC Class Codes: B65D 81/03 Wrappers or envelopes with shock-absorbing properties, e.g. bubble films for thermal insulating purposes B65D81/3888
• CPC Class Codes: Y10S 493/967 Dunnage, wadding, stuffing, or filling excelsior
• CPC Class Codes: Y10T 428/24562 Interlaminar spaces
• CPC Class Codes: Y10T 428/24612 Composite web or sheet
• CPC Class Codes: Y10T 428/24661 Forming, or cooperating to form cells
• CPC Class Codes: Y10T 428/24669 Aligned or parallel nonplanarities
• CPC Class Codes: Y10T 428/31725 Of polyamide
• CPC Class Codes: Y10T 428/3175 Next to addition polymer from unsaturated monomer[s]
• CPC Class Codes: Y10T 428/31757 Polymer of monoethylenically unsaturated hydrocarbon

Abstract

A cushioning material is disclosed which includes two laminated films between which a plurality of air tight cells are formed. Each of the films is composed of an intermediate layer formed of an aromatic polyamide resin and two surface layers formed of a polyolefin resin and provided on both sides of the intermediate layer, wherein the aromatic polyamide resin is one obtained by polycondensing m-xylylenediamine with an aliphatic dicarboxylic acid selected from the group consisting of adipic acid, terephthalic acid, isophthalic acid and mixtures thereof, and the polyolefin resin is a member selected from the group consisting of low density polyethylenes, ethylene/α-olefin copolymers and mixtures thereof.

Claims

1. A cushioning material comprising first and second composite films, each film including an intermediate layer formed of a polyamide resin and a surface layer laminated on each side of said intermediate layer, each surface layer being formed of a polyolefin resin, at least one of said first and second composite films being formed to provide one or more discrete embossments, and said first and second composite films being bonded to form a substantially unitary structure and to seal said embossments so that one or more air-tight cells are defined between said first and second composite films, said polyamide resin including an aromatic polyamide resin selected from the group consisting of (a) a first product obtained by polycondensing m-xylylenediamine with adipic acid, (b) a second product obtained by polycondensing m-xylylenediamine with a mixture of dicarboxylic acids composed of 55-70 mol % of adipic acid, 20-30 mol % of isophthalic acid and 5-20 mol % of terephthalic acid, the total amount of the isophthalic acid and terephthalic acid in said mixture being in the range of 30-45 mol % and (c) a blend of 60-40% by weight of said first product (a) and 40-60% by weight of said second product (b), and Nylon6 in an amount of 10-90% by weight of said aromatic polyamide resin, and said polyolefin resin being a member selected from the group consisting of low density polyethylenes, copolymers of ethylene and an α

-olefin and mixtures thereof.

2. A cushioning material according to claim 1, wherein said polyolefin resin is a mixture of 30-70% by weight of the low density polyethylene and 70-30% by weight of the ethylene/α

-olefin copolymer.

3. A cushioning material according to claim 2, wherein said ethylene/α

-olefin copolymer has an α

-olefin content of 1-15 mole %.

4. A cushioning material according to claim 2, wherein said α

-olefin is butene-1.