Methods for producing composite webs with reinforcing discrete polymeric regions

• US 6,942,894 B2
• Filed: 11/05/2001
• Issued: 09/13/2005
• Est. Priority Date: 11/05/2001
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Wood, Leigh E., Eaton, Bradley W., Alberg, Randall L.
• Primary Examiner(s): Rossi, Jessica
• Application Number:
  US10/012,900
• Publication Number:
  US 20030084996A1
• Time in Patent Office: 1,408 Days
• Field of Search: 156/324, 156290-291, 156/310, 156/553, 156/582, 156/583.1, 427/428.01, 427/428.06, 427/256, 427/428, 427/208.2, 427/208.1, 118/211, 118/212, 118/244, 118/248, 118/249, 118/258, 442/76, 442/102, 442/104, 442/103, 442/149, 442/150, 442/172, 442/118, 442/173, 442/174, 442164-171, 442176-177, 604/366, 604/385.31, 604/370, 492/30, 492/33, 492/35, 492/36, 428/195.1, 428/198, 428/200, 428/201, 101/153, 101/155, 101/156, 101/157, 101/170, 101/178, 101/174, 101/175, 101/216, 101/219, 101/328, 101/375, 101/211, 101/483, 227/2
• US Class Current: 427/256
• 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

Abstract

Methods of manufacturing composite webs including a substrate with one or more reinforcing discrete polymeric regions located on or within the composite web are disclosed. Molten nonelastomeric thermoplastic material of the discrete polymeric region is forced against the substrate by a transfer roll. If the substrate is porous, fibrous, etc., a portion of the nonelastomeric thermoplastic composition may infiltrate the substrate and/or encapsulate fibers of the substrate.

Claims

1. A method for producing a composite web, the method comprising:

providing a transfer roll comprising an exterior surface that comprises one or more depressions formed therein, wherein the one or more depressions comprise at least one depression that comprises a composite depression formed by a plurality of cells, and wherein the one or more depressions comprise at least one depression that comprises an island located therein;

delivering a molten nonelastomeric thermoplastic composition onto the exterior surface of the transfer roll;

wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll, wherein a portion of the molten nonelastomeric thermoplastic composition enters the one or more depressions, and further wherein the portion of the molten nonelastomeric thermoplastic composition in the one or more depressions remains in the one or more depressions after wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll; and

transferring at least a portion of the molten nonelastomeric thermoplastic composition in the one or more depressions to a first major surface of a substrate by contacting the first major surface of the substrate to the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions, followed by separating the substrate from the transfer roll, wherein one or more discrete polymeric regions comprising the nonelastomeric thermoplastic composition are located on the first major surface of the substrate after separating the substrate from the transfer roll.

2. A method according to claim 1, wherein the plurality of cells forming the composite depression overlap with each other.

3. A method according to claim 1, wherein the transferring further comprises forcing the first major surface of the substrate against the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions.

4. A method according to claim 1, wherein the first major surface of the substrate comprises fibers, and further wherein the transferring further comprises encapsulating at least a portion of at least some of the fibers in the molten nonelastomeric thermoplastic composition by forcing the first major surface of the substrate against the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions.

5. A method according to claim 1, wherein substantially all of the one or more depressions are substantially filled with the molten nonelastomeric thermoplastic composition after the wiping and before the transferring.

6. A method according to claim 1, wherein the at least one depression of the one or more depressions forms a discrete polymeric region on the first major surface of the substrate in which a portion of the first major surface of the substrate is located within a surrounding ring of the nonelastomeric thermoplastic composition, and wherein the method further comprises providing an opening through the substrate within the surrounding ring of the nonelastomeric thermoplastic composition.

7. A method according to claim 1, wherein the one or more depressions comprise a plurality of depressions comprising depressions having at least two different shapes.

8. A method according to claim 1, wherein each depression of the one or more depressions comprise a volume of about 3 cubic millimeters or more.

9. A method according to claim 1, wherein each depression of the one or more depressions defines a depression volume, and further wherein the one or more depressions comprises at least two depressions that define different depression volumes.

10. A method according to claim 1, wherein a footprint of each depression of the one or more depressions comprises an area of about 4 square millimeters or more.

11. A method according to claim 1, wherein the molten thermoplastic composition does not comprise tackifiers.

12. A method according to claim 1, further comprising heating the exterior surface of the roll to a temperature that is at or above a melt temperature of the thermoplastic composition.

13. A method according to claim 1, wherein the method further comprises laminating a second substrate to the first major surface of the first substrate, wherein the one or more discrete polymeric regions on the first substrate are located between the first substrate and the second substrate after laminating the second substrate to the first substrate.

14. A method according to claim 1, wherein the first major surface of the substrate comprises a porous surface, and wherein the transferring further comprises forcing a portion of the first major surface of the substrate into the one or more depressions, wherein a portion of the molten nonelastomeric thermoplastic composition in the one or more depressions infiltrates the porous surface within the one or more depressions.

15. A method according to claim 14, wherein the porous surface of the substrate comprises fibers, and further wherein the transferring further comprises encapsulating at least a portion of at least some of the fibers in the molten nonelastomeric thermoplastic composition.

16. A method for producing a composite web, the method comprising:

providing a transfer roll comprising an exterior surface that comprises one or more depressions formed therein, wherein the one or more depressions comprise at least one depression that comprises a composite depression formed by a plurality of overlapping cells;

delivering a molten nonelastomeric thermoplastic composition onto the exterior surface of the transfer roll;

wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll, wherein a portion of the molten nonelastomeric thermoplastic composition enters the one or more depressions, and further wherein the portion of the molten nonelastomeric thermoplastic composition in the one or more depressions remains in the one or more depressions after wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll;

forcing a portion of a first major surface of a substrate into the one or more depressions, wherein the first major surface comprises a porous surface comprising fibers, and wherein a portion of the nonelastomeric thermoplastic composition in the one or more depressions infiltrates the porous surface, and still further wherein the molten nonelastomeric thermoplastic composition encapsulates at least a portion of at least some of the fibers; and

separating the substrate from the transfer roll, wherein one or more discrete polymeric regions comprising the nonelastomeric thermoplastic composition are located on the first major surface of the substrate after separating the substrate from the transfer roll.

17. A method according to claim 16, wherein each depression of the one or more depressions defines a depression volume, and further wherein the one or more depressions comprises at least two depressions that define different depression volumes.

18. A method according to claim 16, wherein at least one discrete polymeric region of the one or more discrete polymeric regions comprises a shape extending continuously along a length of the substrate.

19. A method according to claim 16, wherein the one or more depressions comprise a plurality of depressions comprising depressions having at least two different shapes.

20. A method according to claim 16, wherein each depression of the one or more depressions comprise a depression volume of about 3 cubic millimeters or more.

21. A method according to claim 16, wherein a footprint of each depression of the one or more depressions comprises an area of about 4 square millimeters or more.

22. A method according to claim 16, wherein the molten thermoplastic composition does not comprise tackifiers.

23. A method according to claim 16, further comprising heating the exterior surface of the roll to a temperature that is at or above a melt temperature of the thermoplastic composition.

24. A method for producing a composite web, the method comprising:

providing a transfer roll comprising an exterior surface that comprises one or more depressions formed therein;

delivering a molten nonelastomeric thermoplastic composition onto the exterior surface of the transfer roll;

wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll, wherein a portion of the molten nonelastomeric thermoplastic composition enters the one or more depressions, and further wherein the portion of the molten nonelastomeric thermoplastic composition in the one or more depressions remains in the one or more depressions after wiping the molten nonelastomeric thermoplastic composition from the exterior surface of the transfer roll;

transferring at least a portion of the molten nonelastomeric thermoplastic composition in the one or more depressions to a first major surface of a first substrate by contacting the first major surface of the first substrate to the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions, followed by separating the first substrate from the transfer roll, wherein one or more discrete polymeric regions comprising the nonelastomeric thermoplastic composition are located on the first major surface of the first substrate after separating the first substrate from the transfer roll; and

laminating a second substrate to the first major surface of the first substrate, wherein the one or more discrete polymeric regions on the first substrate are located between the first substrate and the second substrate after laminating the second substrate to the first substrate, wherein the second substrate comprises one or more discrete polymeric regions located on a first major surface of the second substrate prior to laminating the second substrate to the first substrate, and wherein the one or more discrete polymeric regions on the second substrate are located between the first substrate and the second substrate after laminating the second substrate to the first substrate.

25. A method according to claim 24, wherein the transferring further comprises forcing the first major surface of the first substrate against the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions.

26. A method according to claim 24, wherein the first major surface of the first substrate comprises fibers, and further wherein the transferring further comprises encapsulating at least a portion of at least some of the fibers in the molten nonelastomeric thermoplastic composition by forcing the first major surface of the first substrate against the exterior surface of the transfer roll and the molten nonelastomeric thermoplastic composition in the one or more depressions.

27. A method according to claim 24, wherein the one or more depressions in the transfer roll comprise at least one depression that comprises a composite depression formed by a plurality of cells.

28. A method according to claim 24, wherein the molten thermoplastic composition does not comprise tackifiers.

29. A method according to claim 24, further comprising heating the exterior surface of the roll to a temperature that is at or above a melt temperature of the thermoplastic composition.

30. A method according to claim 24, wherein the laminating of the first substrate to the second substrate is not assisted by additional materials.

31. A method according to claim 24, wherein the first major surface of the first substrate comprises a porous surface, and wherein the transferring further comprises forcing a portion of the first major surface of the first substrate into the one or more depressions, wherein a portion of the molten nonelastomeric thermoplastic composition in the one or more depressions infiltrates the porous surface within the one or more depressions.

32. A method according to claim 31, wherein the porous surface of the first substrate comprises fibers, and further wherein the transferring further comprises encapsulating at least a portion of at least some of the fibers in the molten nonelastomeric thermoplastic composition.