Method for improved bond strength in an elastomeric material

• US 7,108,759 B2
• Filed: 12/19/2003
• Issued: 09/19/2006
• Est. Priority Date: 12/19/2003
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: VanGompel, Paul T., You, Frederique, Thorson, Russell E.
• Primary Examiner(s): Sells, James
• Application Number:
  US10/741,916
• Publication Number:
  US 20050133144A1
• Time in Patent Office: 1,005 Days
• Field of Search: 156/73.1, 156/161, 156/163, 156/164, 156/166, 156/196, 156/199, 156/200, 156/226, 156/227, 156/229, 156/269, 156/459, 156/461, 156/522, 156/580.1, 156/580.2, 156/442, 156/443, 156/444, 156/494, 156/495, 156/496, 425/174.2, 167/229, 167/269, 264/442, 264/443, 264/444
• US Class Current: 156/73.1
• CPC Class Codes: A61F 13/15593 having elastic ribbons fixed thereto; Devices for applying the ribbons
• CPC Class Codes: A61F 13/4902 characterised by the elastic material
• CPC Class Codes: B29C 65/00 Joining or sealing of preformed parts , e.g. welding of plastics materials; Apparatus therefor general aspects of processes or apparatus for joining preformed parts B29C66/00; using porous material formed by internal pressure generated therein for joining preformed parts B29C44/1228, B29C44/326
• CPC Class Codes: B29C 65/087 using both a rotary sonotrode and a rotary anvil
• CPC Class Codes: B29C 65/8207 by mechanical methods
• CPC Class Codes: B29C 65/8215 Tensile tests
• CPC Class Codes: B29C 66/0222 without removal of material, e.g. cleaning by air blowing or using brushes
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/344 Stretching or tensioning the joint area during joining
• CPC Class Codes: B29C 66/43 Joining a relatively small portion of the surface of said articles B29C66/45 takes precedence
• CPC Class Codes: B29C 66/431 Joining the articles to themselves B29C66/4322 and B29C66/4332 take precedence
• CPC Class Codes: B29C 66/433 Casing-in, i.e. enclosing an element between two sheets by an outlined seam for bookbinding B42C11/06; for packaging B65B; by laminating B32B37/00; enclosing tubular articles between substantially flat elements B29C66/53261
• 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 66/723 being multi-layered B29C66/7292, B29C66/72941 take precedence
• CPC Class Codes: B29C 66/729 Textile or other fibrous material made from plastics
• CPC Class Codes: B29C 66/7294 Non woven mats, e.g. felt
• CPC Class Codes: B29C 66/7392 characterised by the material of at least one of the parts being a thermoplastic
• CPC Class Codes: B29C 66/73921 characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29C 66/7394 characterised by the material of at least one of the parts being a thermoset
• CPC Class Codes: B29C 66/83413 cooperating rollers, cylinders or drums
• CPC Class Codes: B29C 66/83415 : the contact angle between said rollers, cylinders or drums and said parts to be joined being a non-zero angle B29C66/83433 takes precedence
• CPC Class Codes: B29C 66/934 : by controlling or regulating the speed
• CPC Class Codes: B29C 66/939 : characterised by specific speed values or ranges
• CPC Class Codes: B29C 66/949 : characterised by specific time values or ranges
• CPC Class Codes: B29C 66/9513 : characterised by specific vibration frequency values or ranges
• CPC Class Codes: B29C 66/9517 : characterised by specific vibration amplitude values or ranges
• CPC Class Codes: B29K 2021/00 : Use of unspecified rubbers as moulding material
• CPC Class Codes: B29K 2023/00 : Use of polyalkenes or derivatives thereof as moulding material
• CPC Class Codes: B29K 2023/10 : Polymers of propylene
• CPC Class Codes: B29K 2023/12 : PP, i.e. polypropylene
• CPC Class Codes: B29K 2067/00 : Use of polyesters or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2223/00 : Use of polyalkenes or derivatives thereof as reinforcement
• CPC Class Codes: B29L 2009/00 : Layered products
• CPC Class Codes: B29L 2031/4878 : Diapers, napkins
• CPC Class Codes: B32B 2038/0028 : Stretching, elongating
• CPC Class Codes: B32B 2307/51 : Elastic
• CPC Class Codes: B32B 2310/028 : using vibration, e.g. sonic or ultrasonic
• CPC Class Codes: B32B 2437/00 : Clothing anti-ballistic clothing B32B2571/02
• CPC Class Codes: B32B 25/08 : of synthetic resin
• CPC Class Codes: B32B 2555/02 : Diapers or napkins
• CPC Class Codes: B32B 27/08 : of synthetic resin
• CPC Class Codes: B32B 37/00 : Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
• CPC Class Codes: B32B 37/203 : One or more of the layers being plastic
• CPC Class Codes: B32B 7/04 : Interconnection of layers

Abstract

A method for increasing the bond strength of ultrasonic bonds in elastomeric materials comprising elongating the elastomeric materials prior to ultrasonically bonding the materials.

Claims

1. A method of increasing the strength of ultrasonic bonds in a web of elastomeric material, the method comprising:

elongating a first elastomeric material to a first elongation from about 25% to about 200%;

elongating a second elastomeric material to a second elongation from about 25% to about 200%;

feeding the first elastomeric material and the second elastomeric material through an ultrasonic bonding apparatus at a predetermined speed and dwell time; and

ultrasonically bonding the first elastomeric material to the second elastomeric material while the materials are elongated to form at least one ultrasonic bond having a bond strength of at least about 6 kg.

2. The method of claim 1 where the first elastomeric material and the at least second elastomeric material are elongated to the same degree.

3. The method of claim 1 where the first elastomeric material and the at least second elastomeric material are elongated to an elongation from about 40% to about 150%.

4. The method of claim 3 where the first elastomeric material and the at least second elastomeric material are elongated to an elongation from about 50% to about 125%.

5. The method of claim 4 where the first elastomeric material and the at least second elastomeric material are elongated to an elongation from about 65% to about 111%.

6. The method of claim 5 where the first elastomeric material and the at least second elastomeric material are elongated to an elongation of about 89%.

7. The method of claim 1 where the speed is at least about 50 inches/second.

8. The method of claim 7 where the speed is at least about 55 inches/second.

9. The method of claim 8 where the speed is at least about 60 inches/second.

10. The method of claim 9 wherein the speed is about 68 inches/second.

11. The method of claim 1 where the ultrasonic bond has a bond strength of at least about 7 kg.

12. The method of claim 11 where the ultrasonic bond has a bond strength of at least about 8.0 kg.

13. The method of claim 1 where at least one of the first and the second materials comprises a stretch bonded laminate.

14. The method of claim 13 where at least one of the first and the second materials comprises a vertical filament stretch bonded laminate.

15. The method of claim 13 where at least one of the first and the second materials comprises a continuous filament stretch bonded laminate.

16. The method of claim 1 where at least one of the first and the second material comprises an elastomeric film.

17. The method of claim 16 where the elastomeric film is selected from the group consisting of polyesters, polyolefins, and combinations thereof.

18. The method of claim 1 where the elongated first material is ultrasonically bonded to the elongated second material using a plunge ultrasonic bonder.

19. The method of claim 1 where the elongated first material is ultrasonically bonded to the elongated second material using a rotary ultrasonic bonder.

20. The method of claim 1 where at least one of the elastomeric materials is elongated longitudinally.

21. The method of claim 1 where at least one of the elastomeric materials is elongated transversely.

22. The method of claim 1 where at least one of the elastomeric materials is elongated both longitudinally and transversely.

23. The method of claim 1 where the two webs of elastomeric materials comprise a single sheet of material that has been folded at least once to create two or more layers.

24. The method of claim 1 where the dwell time is from about 0.20 seconds to about 3.0 seconds.

25. The method of claim 24 where the dwell time is from about 0.26 seconds to about 2.6 seconds.

26. A method of increasing the strength of ultrasonic bonds in a web of elastomeric material, the method comprising:

elongating a first elastomeric material to a first elongation;

elongating at least a second elastomeric material to a second elongation;

feeding the elastomeric materials through an ultrasonic bonding apparatus at a production line speed of at least about 55 inches/second; and

ultrasonically bonding a portion of the first elastomeric material to a portion of the at elastic second elastomeric material while the materials are elongated to form an ultrasonic bond having a bond strength of at least about 6 kg.

27. A method of increasing the strength of ultrasonic bonds in a web of elastomeric material, the method comprising:

elongating a first elastomeric material from about 25% to about 200%;

elongating at least a second elastomeric material from about 25% to about 200%;

feeding the elastomeric materials through an ultrasonic bonding apparatus at a predetermined speed and bond dwell time; and

ultrasonically bonding the first elastomeric material to the at least second elastomeric material while the materials are elongated to form at least one ultrasonic bond having a bond strength of at least about 6 kg.

28. An apparatus for ultrasonically bonding at least two webs of elastomeric material comprising:

a first elongating unit operative to elongate at least a portion of a first web of elastomeric material to an elongation of from about from about 25% to about 200%;

at least a second elongating unit operative to elongate at least a portion of a second web of elastomeric material to an elongation of from about from about 25% to about 200%;

an ultrasonic bonding unit operative to ultrasonically bond the elongated portion of the first web to the elongated portion of the second web to a bond strength of at least about 6 kg.

29. A method of increasing the ultrasonic bond strength in the side seams of a pant-type garment comprising:

providing a web of elastomeric material;

elongating the web of elastomeric material to a predetermined elongation of from about from about 25% to about 200%;

cutting the web of elastomeric material to form an elongated front elastomeric panel having a first longitudinal side edge and a second longitudinal side edge and an elongated back elastomeric panel having a first longitudinal side edge and a second longitudinal side edge;

attaching an absorbent structure to the elongated front and back elastomeric panels to form an absorbent composite having a longitudinal axis and a transverse axis;

folding the absorbent composite along the transverse axis of the composite; and

ultrasonically bonding the first side edge of the front panel to the first side edge of the back panel and the second side edge of the front panel to the second side edge of the back panel while the panels are elongated to form side seams;

wherein the side seams comprise at least one ultrasonic bond having a bond strength of at least about 6 kg.