Molding fastener elements on folded substrate

• US 20060226571A1
• Filed: 04/06/2005
• Published: 10/12/2006
• Est. Priority Date: 04/06/2005
• Status: Active Grant

• Current Assignee: Velcro IP Holdings LLC
• Original Assignee: Velcro Industries BV (Chartwell Industries Ltd)
• Inventors: Clune, William P.
• Granted Patent: US 7,601,284 B2
• Time in Patent Office: Days
• US Class Current: 264/166
• CPC Class Codes: A44B 18/0053 in which each part has similar elements
• CPC Class Codes: A44B 18/0084 Double-sided
• 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 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: Y10T 24/27 including readily dissociable fastener having numerous, protruding, unitary filaments randomly interlocking with, and simultaneously moving towards, mating structure [e.g., hook-loop type fastener]
• CPC Class Codes: Y10T 24/2767 having several, repeating, interlocking formations along length of filaments
• CPC Class Codes: Y10T 428/24017 Hook or barb

Abstract

A method for forming a fastener product includes folding a sheet material about a longitudinal fold line to form a longitudinal edge portion overlapping only an adjacent portion of the sheet material, leaving another portion of the sheet material exposed as a remainder portion. The folded sheet material is continuously introduced to a gap adjacent to a surface of a rotating mold roll. Moldable resin is introduced between the sheet material and the mold roll to fill fixed cavities in the rotating mold roll to form portions of the fastener elements as stems bonded to one of the overlapping edge portion and the remainder portion. Additional material is bonded to the other of the overlapping edge portion and the remainder portion with the bonding occurring in the gap. The resin is solidified, then, stripped from the surface of the mold roll by pulling the stems from their respective cavities.

Claims

1. A method for forming a fastener product having multiplicities of fastener elements extending from a strip form base, the method comprising:

folding a sheet material about a first longitudinal fold line to form a first longitudinal edge portion overlapping only a first adjacent portion of the sheet material, leaving another portion of the sheet material exposed as a primary remainder portion;

continuously introducing the folded sheet material to a gap defined adjacent to a peripheral surface of a rotating mold roll, while

introducing moldable resin between the sheet material and the mold roll, such that the resin fills an field of fixed cavities defined in the rotating mold roll to form an field of molded stems bonded to one of the first longitudinal edge portion and the primary remainder portion, while

introducing an additional material to the gap, such that the additional material is bonded to the other of the first longitudinal edge portion and the primary remainder portion;

forming engageable heads on the molded stems;

solidifying the resin; and

then

stripping the solidified resin from the peripheral surface of the mold roll by pulling the stems from their respective cavities.

2. The method of claim 1 further comprising, after stripping, unfolding the sheet material to its original width.

3. The method of claim 1 wherein the engageable heads are formed by molding the heads on the stems in the cavities of the mold roll.

4. The method of claim 1 wherein the engageable heads are formed by deforming resin of the molded stems after stripping the solidified resin from the peripheral surface of the mold roll.

5. The method of claim 4 wherein the stems are formed into fastener elements by applying heat and pressure to distal ends of the stems.

6. The method of claim 1 wherein bonding an additional material to the other of the first longitudinal edge portion and the primary remainder portion comprises introducing moldable resin between the sheet material and the mold roll, to fill a second field of fixed cavities defined in the rotating mold roll and form a second field of molded stems bonded to the other of the first longitudinal edge portion and the primary remainder portion.

7. The method of claim 1 wherein bonding an additional material to the other of the first longitudinal edge portion and the primary remainder portion comprises introducing a loop material between the sheet material and the mold roll, such that the loop material is laminated to the other of the first longitudinal edge portion and the primary remainder portion.

8. The method of claim 7 wherein the loop material is a non-woven fabric.

9. The method of claim 1 wherein the gap comprises a nip defined between the rotating mold roll and a counter-rotating pressure roll.

10. The method of claim 1 further comprising, before introducing the folded sheet material to the gap, folding the sheet material about a second longitudinal fold line in the primary remainder portion to form a second longitudinal edge portion overlapping a second adjacent portion of the primary remainder portion.

11. The method of claim 10 wherein the second longitudinal fold line bisects the primary remainder portion such that the second longitudinal edge portion abuts the first longitudinal edge portion.

12. The method of claim 11 wherein the field of molded stems is bonded to the second longitudinal edge portion.

13. The method of claim 12 wherein the additional material bonded to the first longitudinal edge portion.

14. The method of claim 13 wherein introducing the additional material comprises introducing moldable resin between the sheet material and the mold roll, to fill a second field of fixed cavities defined in the rotating mold roll and form a second field of molded stems bonded to the other of the first longitudinal edge portion and the second longitudinal edge portion.

15. The method of claim 13 wherein introducing the additional material comprises introducing a loop material between the sheet material and the mold roll, such that the loop material is laminated to the other of the first longitudinal edge portion and the second longitudinal portion.

16. The method of claim 10 wherein a portion of the primary remainder portion adjacent to the overlapped first adjacent portion remains exposed to the mold roll

17. The method of claim 16 wherein the field of molded stems is bonded to the first longitudinal edge portion.

18. The method of claim 17 wherein the additional material is bonded to the second longitudinal edge portion.

19. The method of claim 18 wherein introducing the additional material comprises introducing moldable resin between the sheet material and the mold roll, to fill a second field of fixed cavities defined in the rotating mold roll and form a second field of molded stems bonded to the second longitudinal edge portion.

20. The method of claim 18 wherein introducing the additional material comprises introducing a loop material between the sheet material and the mold roll, such that the loop material is laminated to the second longitudinal edge portion.