Fastener assembly with improved temporary attachment layer

• US 4,563,380 A
• Filed: 08/31/1984
• Issued: 01/07/1986
• Est. Priority Date: 07/10/1984
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Black, Philip D., Rhoe, Dale G.
• Primary Examiner(s): Thomas, Alexander S.
• Application Number:
  US06/646,900
• Time in Patent Office: 494 Days
• Field of Search: 428/100, 428/900, 428/308.4, 428/311.1, 428/317.1, 428/329, 428/120, 24/306, 24/444, 297/DIG. 6, 264/46.7
• US Class Current: 428/100
• CPC Class Codes: A44B 18/0076 Adaptations for being fixed to a moulded article during moulding
• CPC Class Codes: A44D 2203/00 Fastening by use of magnets
• CPC Class Codes: B29C 33/16 using magnetic means
• CPC Class Codes: B29C 44/1271 the preformed parts being partially covered
• CPC Class Codes: Y10S 428/90 Magnetic feature
• CPC Class Codes: Y10T 24/2708 Combined with diverse fastener
• CPC Class Codes: Y10T 24/2725 with feature facilitating, enhancing, or causing attachment of filament mounting surface to support therefor
• CPC Class Codes: Y10T 428/24017 Hook or barb
• CPC Class Codes: Y10T 428/24182 Inward from edge of web or sheet
• CPC Class Codes: Y10T 428/249958 Void-containing component is synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/249962 Void-containing component has a continuous matrix of fibers only [e.g., porous paper, etc.]
• CPC Class Codes: Y10T 428/249982 With component specified as adhesive or bonding agent
• CPC Class Codes: Y10T 428/257 Iron oxide or aluminum oxide

Abstract

An elongate fastener assembly comprising a flexible polymeric backing strip from which project a multiplicity of headed stems adapted to engage loops on materials pressed against the heads, and an open porous permanent attachment layer attached to the surface of the backing strip opposite the stems which has sufficient open area to receive foam to permanently attach the fastener assembly to a foamed article. The fastener assembly has a temporary attachment layer comprising granular ferromagnetic material in a polymeric binder sandwiched between the backing strip and the permanent attachment layer which is adapted to be attracted by magnets to temporarily hold the fastener assembly in position during a foaming process, and has a heat shrinkable film cover means overlaying the heads attached to the edges of the backing strip that will shrink transversely to expose the heads upon the application of heat below 125° C.

Claims

1. In an elongate fastener assembly comprising a polymeric backing strip having first and second major surfaces;

a multiplicity of stems each secured at one end to said backing strip, projecting generally normally to the first surface of said backing strip, and having enlarged heads at their ends opposite said backing strip adapted to engage loops on materials pressed against said heads;

an open porous permanent attachment layer atached to the second major surface of said backing strip, said permanent attachment layer having sufficient open areas to afford movement of foam into said permanent attachment layer to permanently attach said fastener assembly to a foamed article; and

a temporary attachment layer comprising ferromagnetic material sandwiched between the second major surface of said backing and said attachment layer, said temporary attachment layer being adapted to be attracted by magnets to temporarily hold said fastner assembly in position during the foaming process;

the improvement wherein the temporary attachment layer comprises ferromagnetical particles dispersed within a polymeric bonding material, said bonding material exhibiting essentially the same shrinkage as said backing strip when said fastener assembly is exposed to temperatures around 125°

C., so that the temperatures resulting from the foaming process will not cause a substantial relative change in length between the backing strip and the temporary attachment layer.

2. An elongate fastener according to claim 1 wherein said binder comprises vinyl material and said ferromagnetic material is iron particles.

3. In an elongate fastener assembly comprising a polymeric backing strip having first and second major surfaces:

a multiplicity of stems each secured at one end to said backing strip, projecting generally normally to the first surface of said backing strip, and having enlarged heads at their ends opposite said backing strip adapted to engage loops on materials pressed against said heads;

an open porous permanent attachment layer attached to the second major surface of said backing strip, said permanent attachment layer having sufficient open areas to afford movement of foam into said permanent attachment layer to permanently attach said fastener assembly to a foamed article; and

a temporary attachment layer comprising ferromagnetic material sandwiched between the second major surface of said backing and said attachment layer, said temporary attachment layer being adapted to be attracted by magnets to temporarily hold said fastener assembly in position during the foaming process;

the improvement wherein the temporary attachment layer comprises ferromagnetical particles dispersed within a polymeric bonding material, said bonding material having generally the same coefficient of thermal expansion as said backing strip and exhibiting essentially the same shrinkage as said backing strip when said fastener assembly is exposed to temperatures around 125°

C., so that the temperatures resulting from the foaming process will not cause a substantial relative change in length between the backing strip and the temporary attachment layer.

4. An elongate fastener according to claim 3 wherein said binder comprises vinyl material and said ferromagnetic material is iron particles.