Shaped foam

• US 4,996,092 A
• Filed: 02/05/1990
• Issued: 02/26/1991
• Est. Priority Date: 02/20/1989
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Bastow, David R., Francis, David J.
• Primary Examiner(s): Van Balen, William J.
• Application Number:
  US07/475,116
• Time in Patent Office: 386 Days
• Field of Search: 264/321, 428/157, 428/159, 428/160, 428/317.1, 428/317.3, 428/319.3, 428/906
• US Class Current: 428/157
• CPC Class Codes: B05B 12/24 made at least partly of flexible material, e.g. sheets of paper or fabric
• CPC Class Codes: B05B 12/265 between a door and a post, e.g. foam strips
• CPC Class Codes: B29C 59/007 Forming single grooves or ribs, e.g. tear lines, weak spots by moulding B29C37/0057; folding lines B29C53/06; in metal articles B21D17/00; by cutting B26D3/08
• CPC Class Codes: B29C 65/004 Cold joining
• CPC Class Codes: B29C 65/02 by heating, with or without pressure
• CPC Class Codes: B29C 65/08 using ultrasonic vibrations non-plastics element to plastics elements B29C65/645
• CPC Class Codes: B29C 65/7435 the tool being a roller
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/727 being porous, e.g. foam
• CPC Class Codes: B29C 66/8322 Joining or pressing tools reciprocating along one axis
• CPC Class Codes: B29K 2023/06 PE, i.e. polyethylene
• CPC Class Codes: B29K 2025/06 PS, i.e. polystyrene
• CPC Class Codes: B29K 2027/06 PVC, i.e. polyvinylchloride
• CPC Class Codes: B29K 2049/00 Use of polyacetylene or cyanic ester resins, i.e. polymers having one or more carbon-to-carbon triple bonds or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2067/00 Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2083/00 Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material
• CPC Class Codes: B29K 2105/04 cellular or porous
• CPC Class Codes: B29L 2007/007 Narrow strips, e.g. ribbons, tapes, bands belts B29L2029/00; tapes as carrier of sound or information B29L2017/008
• CPC Class Codes: Y10S 428/906 Roll or coil
• CPC Class Codes: Y10T 428/24488 : Differential nonuniformity at margin
• CPC Class Codes: Y10T 428/24504 : Component comprises a polymer [e.g., rubber, etc.]
• CPC Class Codes: Y10T 428/24512 : Polyurethane
• CPC Class Codes: Y10T 428/249982 : With component specified as adhesive or bonding agent
• CPC Class Codes: Y10T 428/249983 : As outermost component
• CPC Class Codes: Y10T 428/249991 : Synthetic resin or natural rubbers

Abstract

Elongate foam strips are formed by cold welding a flat foam web using blunt rotary cutters. A manually separable array of foam strips is formed by welding a flat foam web along a series of parallel lines, using cold welding or other joining methods, and packaging the array without separating the individual strips from one another.

Claims

1. A foam article formed of a cold-weldable foam, the article being in the form of an elongate strip comprising a curved surface, the strip having at least one welded seam along its longitudinal length which maintains the configuration of the curved surface.

2. An article as claimed in claim 1, the article comprising a pair of welded seams, and the article having an oval or circular cross-section, a density that increases near the weld seams, and a length of more than one meter.

3. An article as claimed in claim 1, wherein the strip is at least partially coated with a layer of adhesive.

4. An article as claimed in claim 3, wherein the strip is in the form of a paint masking gasket whose length and diameter are suitable for disposition of the strip between a vehicle door and a vehicle body.

5. An article as claimed in claim 1, comprising a pair of welded seams inclined towards each other, the strip having a generally conical surface.

6. An article as claimed in claim 5, wherein the strip is in the form of an ear plug.

7. An array of adjacent, elongate parallel foam strips, each strip comprising a curved surface between two longitudinal weld seams which maintain the curvature of the surface, adjacent strips being joined to each other by a longitudinal weld seam, and the individual strips being manually separable from the array.

8. An array as claimed in claim 7, wherein at least a portion of the surface of each strip is coated with a pressure sensitive adhesive.

9. An array as claimed in claim 7, wherein the foam is cold-weldable.

10. An array as claimed in claim 7, having a length of at least one meter, the array being wound in roll form.

11. A foam article formed of a foam capable of cold welding and having a curved surface maintained under compression by a welded seam, the article being at least partially coated with a surface layer.

12. A foam article as claimed in claim 11, in the form of an elongate pad or block.

13. A foam article as claimed in claim 11, wherein the surface layer comprises a pressure sensitive adhesive.

14. A foam article as claimed in claim 11, wherein the surface layer comprises abrasive particles and a binder.

15. A foam article as claimed in claim 14, wherein a portion of the surface of the article is coated with an abrasive layer and an opposing surface is coated with a pressure sensitive adhesive.

16. A method of producing a foam article in the form of an elongate strip comprising a curved surface, comprising the step of longitudinally compressing a predetermined area of an elongate cold-weldable foam web using a blunt rotary cutter, so that a cold welded seam is formed which secures opposing surfaces of the web to each other at the region of the weld, thereby forming the curved surface.

17. A method as claimed in claim 16, wherein the web is compressed along at least two parallel longitudinal lines to form at least one cord having a pair of longitudinal welded seams and a circular or oval cross-section.

18. A method as claimed in claim 16, wherein the curved surface is at least partially coated with a surface layer comprising a pressure sensitive adhesive.

19. A method as claimed in claim 16, wherein the edge of the blunt rotary cutter has a width of about 0.5 to 1.5 mm.

20. A method of making an array of adjacent elongate foam strips comprising the steps of compressing a foam web along a series of three or more parallel lines to form curved surfaces on the web between the lines, and welding the compressed foam along the parallel lines to maintain the curvature of the surfaces, the welded foam joining adjacent strips but enabling manual separation of the strips along the parallel lines.

21. A method as claimed in claim 20, further comprising the step of winding the array on a core so that the strips can later be unwound from the core and manually separated from one another.

22. A method as claimed in claim 20, wherein the foam is welded using ultrasound or heat.

23. A method as claimed in claim 20, wherein the foam is welded using cold welding.

24. A method as claimed in claim 23, wherein the foam web comprises a polyester foam.