Molding touch fastener elements

• US 7,807,007 B2
• Filed: 12/18/2008
• Issued: 10/05/2010
• Est. Priority Date: 03/23/2005
• Status: Active Grant

• Current Assignee: Velcro IP Holdings LLC
• Original Assignee: Velcro Industries BV (Chartwell Industries Ltd)
• Inventors: Iannazzi, Peter, Gallant, Christopher M., Clarner, Mark A., Tachauer, Ernesto S.
• Primary Examiner(s): Crispino; Richard
• Assistant Examiner(s): Bell; William P
• Application Number:
  US12/338,289
• Publication Number:
  US 20090095411A1
• Time in Patent Office: 656 Days
• Field of Search: 264/172.19, 264/173.1, 264/173.16, 264/173.17, 264/167, 264/177.17, 425/402, 425/403, 156/247, 24442-453
• US Class Current: 156/247
• CPC Class Codes: A44B 18/0049 obtained by moulding processes compression moulding or articles of indefinite length characterised by the shape of the surface B29C43/222; screen moulding B29C67/08
• CPC Class Codes: A44B 18/0069 Details
• CPC Class Codes: A61F 13/625 characterised by the hook
• CPC Class Codes: A61F 13/8405 Additives, e.g. for odour, disinfectant or pH control
• CPC Class Codes: B29C 2043/461 the rollers having specific surface features
• CPC Class Codes: B29C 2043/465 having one or more cavities, e.g. for forming distinct products
• CPC Class Codes: B29C 33/68 Release sheets
• CPC Class Codes: B29C 43/222 characterised by the shape of the surface
• CPC Class Codes: B29C 43/28 incorporating preformed parts or layers, e.g. compression moulding around inserts or for coating articles
• CPC Class Codes: B29C 43/46 Rollers
• CPC Class Codes: B29L 2031/729 Hook and loop-type fasteners
• CPC Class Codes: B32B 2264/101 Glass
• CPC Class Codes: B32B 2264/105 Metal
• CPC Class Codes: B32B 2274/00 Thermoplastic elastomer material thermoplastic elastomer fibres B32B2262/0215, thermoplastic elastomer particles B32B2264/0221, thermoplastic elastomer foam B32B2266/0292
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2307/542 Shear strength
• CPC Class Codes: B32B 2307/5825 Tear resistant
• CPC Class Codes: B32B 2307/726 Permeability to liquids, absorption
• CPC Class Codes: B32B 2432/00 Cleaning articles, e.g. mops, wipes personal care B32B2555/00
• CPC Class Codes: B32B 2437/00 Clothing anti-ballistic clothing B32B2571/02
• CPC Class Codes: B32B 2555/00 : Personal care
• CPC Class Codes: B32B 27/06 : as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/045; next to a bituminous or tarry layer B32B11/046; next to a water setting substance layer B32B13/12; next to a metal layer B32B15/08; next to a glass layer B32B17/10; next to a layer formed of natural mineral fibres or particles B32B19/045; next to a wood layer B32B21/08; next to a cellulosic plastic layer B32B23/08; next to a natural or synthetic rubber layer B32B25/08
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 27/18 : characterised by the use of special additives
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 3/00 : Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
• CPC Class Codes: B32B 3/26 : characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids foam layer B32B5/18; layer of synthetic resin characterised by fillers that create voids or cavities B32B27/205; characterised by an apertured layer
• CPC Class Codes: B32B 3/30 : characterised by a layer formed with recesses or projections, e.g. hollows, grooves, protuberances, ribs apertured layer B32B3/266; layer with cavities or internal voids B32B3/26
• CPC Class Codes: Y10T 156/1007 : Running or continuous length work
• CPC Class Codes: Y10T 156/1043 : Subsequent to assembly
• CPC Class Codes: Y10T 428/24008 : including fastener for attaching to external surface
• CPC Class Codes: Y10T 428/24017 : Hook or barb

Abstract

Methods of forming a sheet-form product can include: providing a forming surface having a multiplicity of inwardly extending forming cavities; forming a multi-layer sheet in the interior of which is a parting surface defined by materials of limited compatibility, material of the sheet lying on each side of the parting surface having peelable tensile strength; pressing the multi-layer sheet against the forming surface to cause the multi-layer sheet to substantially conform to and fill the cavities; and peeling the multi-layer sheet apart at the parting surface, whereby material directly engaging the forming surface defines a sheet-form member having a multiplicity of hollow formations.

Claims

1. A method of forming a sheet-form product, the method comprising:

providing a forming surface having a multiplicity of inwardly extending forming cavities;

forming a multi-layer sheet in the interior of which is a parting surface defined by resin materials of limited compatibility, a first resin of the sheet lying on one side of the parting surface and a second resin lying on an opposite side of the parting surface, the parting surface having peelable tensile strength;

pressing the multi-layer sheet against the forming surface to cause the first resin and the second resin of the multi-layer sheet to substantially conform to and fill the cavities of the forming surface; and

peeling the multi-layer sheet apart at the parting surface, whereby material directly engaging the forming surface defines a sheet-form member having a multiplicity of hollow formations.

2. The method of claim 1 in which the forming cavities define at least stems for fastener elements.

3. The method of claim 2 wherein the forming cavities define cylindrical formations.

4. The method of claim 2 wherein the forming cavities define loop engageable formations.

5. The method of claim 4 wherein the loop engageable formations are molded hooks.

6. The method of claim 1 wherein forming a multi-layer sheet comprises continuously introducing a first molten thermoplastic and a second molten thermoplastic into a gap defined adjacent to the forming surface.

7. The method of claim 1 further comprising, forming a dispensing hole in the hollow formations.

8. The method of claim 7 wherein forming a dispensing hole comprises laser radiating the hollow formations to burn through the sheet-form member.

9. The method of claim 7 wherein forming a dispensing hole comprises mechanically piercing the hollow formations.

10. The method of claim 1 wherein mold pins extend into the forming cavities from a body of the forming surface.

11. The method of claim 1 further comprising, weakening a discrete area of the hollow formations.

12. The method of claim 11 wherein weakening comprises laser radiating the hollow formations for a period of time chosen to decrease the structural strength of a discrete area of the hollow formations without burning through the sheet-form member.

13. The method of claim 1 further comprising filling the hollow formations with a flowable substance.

14. The method of claim 13 further comprising, after filling, bonding a backing layer to the sheet-form member to form a multiplicity of substantially enclosed chambers.

15. The method of claim 14 wherein the flowable substance comprises a component that volatilizes when exposed to the atmosphere.

16. The method of claim 13 further comprising choosing the flowable substance from a group including:

a medicament appropriate for topical application;

an antibiotic;

an analgesic;

components that reduce transmission of ultraviolet radiation; and

components that repel insects.

17. A method of forming a sheet form product, the method comprising:

forming a multi-layer sheet having a first resin layer forming a first broad surface of the multi-layer sheet;

pressing the multi-layer sheet against a forming surface with the first resin layer contacting the forming surface such that the first resin layer and an additional layer of the multi-layer sheet substantially conform to and fill a multiplicity of inwardly extending forming cavities in the forming surface and such that the first resin layer separates remaining portions of the multi-layer sheet from the forming surface;

removing the multi-layer sheet from the forming surface; and

removing the first resin layer from the remaining portions of the multi-layer sheet, the remaining portions of the multi-layer sheet defining a member have stems of fasteners elements integrally molded with and extending from a sheet-form base.

18. The method of claim 17 wherein the remaining portions comprise additives.

19. The method of claim 18 wherein the additives comprise materials, such as titanium dioxide or calcium carbonate, that increase the rate of accumulation of contaminating material on the surfaces the resin and additives contact and the method further comprises sizing a thickness of the first layer to limit contact between the forming surface and the remaining portions.

20. The method of claim 18 wherein the additives comprise materials that increase abrasive characteristics of the remaining portions and the method further comprises sizing a thickness of the first layer to reduce wear on the forming surface from the remaining portions.

21. The method of claim 17 further comprises sizing a thickness of the first layer based on sizes of irregularities in the forming surface.

22. The method of claim 17 further comprising selecting materials for the first layer that have a first flexural modulus and materials for the remaining portions that have a second flexural modulus such that the second flexural modulus is greater than the first flexural modulus.

23. The method of claim 22 wherein the second flexural modulus is greater than 300,000 pounds per square inch.

24. The method of claim 23 wherein the second flexural modulus is greater than 500,000 pounds per square inch.

25. The method of claim 24 wherein the second flexural modulus is greater than 750,000 pounds per square inch.

26. The method of claim 22 wherein removing the multi-layer sheet from the forming surface comprises compressing the first layer between the forming surface and remaining portions.

27. The method of claim 22 further comprising forcing the remaining portions through the first layer.