초록 ▼

A method of and apparatus for fusion bonding a continuous synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuous film substrate. The substrate is advanced continuously through a bonding zone. Continuous direct transit o

A method of and apparatus for fusion bonding a continuous synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuous film substrate. The substrate is advanced continuously through a bonding zone. Continuous direct transit of the fastener strip is effected from thermoplastic extruder downwardly through a short distance to the bonding zone, so that in the short transit distance the fastener strip will retain substantial residual thermoplastic fusion temperature. The fastener profile portion is chilled while the strip is in transit to the bonding zone, solidified and stabilized, but the base portion is left at sufficient residual fusion temperature to remain thermoplastic to the bonding zone where assembly of the strip and substrate is effected by fusion bonding of the base portion to the substrate. An annular rotary heating surface may be applied to a narrow locally limited longitudinal area of the substrate for supplying to such area fusion promoting heat in the bonding zone, such area being aligned with the fastener strip in the assembly. The longitudinal area may be stretched by the rotary heating surface.

대표청구항 ▼

1. A method of fusion bonding a continuous freshly extruded low melt viscosity synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuously running prefabricated film substrate, which comprises: advancing the prefabricat

1. A method of fusion bonding a continuous freshly extruded low melt viscosity synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuously running prefabricated film substrate, which comprises: advancing the prefabricated substrate continuously through a bonding zone in which the substrate is directed to run downwardly; effecting continuous direct free running transit of the fastener strip downwardly from thermoplastic extruder means through a short transit distance to said bonding zone located below said extruder means, so that in such short transit distance said fastener strip as a whole would tend to retain substantial residual thermoplastic fusion temperature; in said free running short transit distance, and before the fastener strip reaches said bonding zone, selectively chilling and thereby solidifying and stabilizing said fastener profile portion of the transitting fastener strip, and thereby preventing deformation of said profile but leaving said base portion at sufficient residual fusion temperature to remain thermoplastic to said bonding zone; at the downstream end of said short transit distance and beyond said chilling step effecting assembly of the still thermoplastic base portion of the otherwise solidified strip with said substrate in said bonding zone, and in said bonding zone pressing the assembled downwardly running strip and substrate together and thereby effecting fusion bonding of said thermoplastic base portion to said substrate; and downstream from said bonding zone setting and curing the bonded assembly. 2. A method according to claim 1, comprising effecting said assembly and pressing together of said strip and said substrate by engaging the same in a downwardly running nip between corunning and cooperating bonding and pinch rolls. 3. A method according to claim 1, which comprises applying auxiliary fusion promoting heat to a narrowly locally limited longitudinal area of said substrate aligned with said fastener strip. 4. A method according to claim 3, which comprises applying said auxiliary fusion promoting heat by running an annular rotary heating surface in contact with said limited longitudinal area of said substrate in advance of said effecting assembly of said strip and said substrate. 5. A method according to claim 3, which comprises applying said auxiliary fusion promoting heat by running an annular rotary heating surface in contact with said limited longitudinal area of said substrate in advance of said effecting assembly of said strip and said substrate and continuing to the point of fusion bonding of said base portion to said substrate. 6. A method according to claim 1, wherein said setting and curing of the bonded assembly comprises running the assembly along a longitudinally downwardly extending heat sink cooling plate, and applying a chilling fluid toward said plate and against said fastener strip bonded to said substrate. 7. A method according to claim 6, which comprises applying both chilling air and water spray toward said plate. 8. A method according to claim 6, comprising applying a water spray as the chilling fluid. 9. A method according to claim 6, which comprises leading the assembly from said plate and over a series of curing rolls. 10. A method according to claim 1, which comprises effecting continuous direct downwardly transit of respectively a male profile fastener strip and a complementary female profile fastener strip from the thermoplastic extruder means through said short transit distance to said bonding zone, in said short transit distance and upstream from said bonding zone chilling and solidifying and stabilizing the fastener profile portions of both of said strips and leaving the base portions of both strips in fused condition, effecting assembly of both of said strips to said substrate in spaced parallel relation in said bonding zone, and effecting fusion bonding of said fused base portions of said strips to said substrate. 11. A method according to claim 10, which comprises after setting and curing of the bonded assembly, folding the assembly between the bonded fastener strips and separably joining the profiles of the fastener strips. 12. A method according to claim 1, comprising applying an annular rotary heating surface to a narrow locally limited longitudinal area of said substrate and thereby stretching and supplying said longitudinal area with fusion promoting heat in said bonding zone, aligning said fastener strip in assembly with the thus heated and stretched longitudinal substrate area in said bonding zone, and engaging and bonding said base portion to said heated longitudinal substrate area. 13. A method according to claim 1, which comprises effecting said chilling by directing a low velocity stream of chilling fluid limited to said profile portion. 14. Apparatus for fusion bonding a continuous freshly extruded low melt viscosity synthetic thermoplastic resin fastener strip having a fastener profile portion and a base portion opposite the profile, to a continuously running prefabricated film substrate, which comprises: means for advancing the prefabricated substrate continuously through a bonding zone in which the substrate is directed to run downwardly; means for thermoplastically extruding the fastener strip for continuous free running direct transit through a short distance downwardly to said bonding zone, so that in such short transit distance, said fastener as a whole would tend to retain substantial residual thermoplastic fusion temperature; means located in said free running short transit distance, and before the fastener strip reaches said bonding zone, for selectively chilling and thereby solidifying and stabilizing said fastener profile portion of the transitting fastener strip, for preventing deformation of said profile, but leaving said base portion of the transitting fastener strip at sufficient residual fusion temperature to remain thermoplastic to said bonding zone; means located at the downstream end of said short transit distance and beyond said chilling means for effecting assembly of the still plastic base portion of the otherwise solidified strip with said substrate in said bonding zone, and for in said bonding zone pressing the assembled downwardly running strip and substrate together and thereby effecting fusion bonding of said thermoplastic base portion to said substrate; and means downstream from said bonding zone for setting and curing the bonded assembly. 15. Apparatus according to claim 14, wherein said means for effecting assembly and fusion bonding comprise corunning and cooperating bonding and pinch rolls. 16. Apparatus according to claim 14, including means for applying auxiliary fusion promoting heat to a narrowly locally limited longitudinal area of said substrate aligned with said fastener strip. 17. Apparatus according to claim 16, wherein said means for applying said auxiliary fusion promoting heat comprises an annular rotary heating surface in contact with said limited longitudinal area of said substrate. 18. Apparatus according to claim 16, wherein said means for applying said auxiliary fusion promoting heat ccmprises an annular rotary heating surface in contact with said limited longitudinal area of said substrate and forms a part of said means for effecting assembly and bonding of said strip and said substrate. 19. Apparatus according to claim 14, wherein said means for setting and curing of the bonded assembly comprises a longitudinally extending heat sink cooling plate, and means for applying a chilling fluid toward said plate and against said fastener strip bonded to said substrate. 20. Apparatus according to claim 19, wherein said means for applying chilling fluid directs both chilling air and water spray toward said plate. 21. Apparatus according to claim 19, wherein said means for applying chilling fluid applies a water spray as the chilling fluid. 22. Apparatus according to claim 19, which comprises means for leading the assembly from said plate and over a series of curing zone rolls. 23. Apparatus according to claim 14, wherein said extruding means is adapted for extruding and effecting continuous direct downward transit of respectively a male profile fastener strip and a complementary female profile fastener strip through said short transit distance to said bonding zone, said means located in said free running short transit distance and before said bonding zone for chilling being adapted for solidifying and stabilizing the fastener profile portions of both of said strips but leaving the base portions of both strips in fused condition, and said means for effecting assembly being adapted for assembling both of said strips to said substrate in spaced parallel relation in said bonding zone and for effecting fusion bonding of said fused base portions of said strips to said substrate. 24. Apparatus according to claim 23, comprising means for folding the assembly between the bonded fastener strips and for separably joining the profiles of the fastener strips after said assembly leaves said means for setting and curing. 25. Apparatus according to claim 14, comprising an annular rotary heating surface adapted to be applied to a narrow locally limited longitudinal area of said substrate for stretching and supplying said longitudinal area with fusion promoting heat in said bonding zone, and means for aligning said fastener strip in assembly with the thus heated and stretched longitudinal substrate area in said bonding zone and for engaging and bonding said base portion to said heated longitudinal substrate area. 26. Apparatus according to claim 14, wherein said means for chilling comprises a nozzle structure for directing a low velocity stream of chilling fluid limited to said profile portion. 27. A method of fusion bonding a fastener strip having a fastener profile and a base portion opposite the profile, to a continuous sheet of film substrate, which comprises: advancing said substrate continuously through a bonding zone; applying an annular rotary heating surface to a narrowly locally limited longitudinal area of said substrate and thereby supplying said longitudinal area with fusion promoting heat in said bonding zone; aligning said fastener strip in assembly with the thus heated longitudinal substrate area in said bonding zone, and engaging and bonding said base portion to said heated longitudinal substrate area; and setting and curing the bonded assembly. 28. A method according to claim 27, which comprises effecting stretching of said limited longitudinal area by the application of said annular rotary heating surface. 29. A method according to claim 27, comprising effecting continuous direct transit of the fastener strip from thermoplastic extruder means through a short distance to said bonding zone, so that in such short transit distance said fastener strip will retain substantial residual thermoplastic fusion temperature; chilling and thereby solidifying and stabilizing said fastener profile portion of the transitting fastener strip, but leaving said base portion at sufficient residual fusion temperature to remain thermoplastic to said bonding zone; and effecting said bonding by the combined thermoplasticity of said base portion and the fusion promoting heated condition of said longitudinal area. 30. Apparatus for fusion bonding a fastener strip having a fastener profile and a base portion opposite the profile, to a continuous sheet of film substrate, ccmprising: means for advancing said substrate continuously through a bonding zone; rotary bonding roll means having an annular heating surface for application to a narrow locally limited longitudinal area of said substrate for thereby supplying said longitudinal area with fusion promoting heat in said bonding zone; means for aligning said fastener strip in assembly with the heated longitudinal substrate area in said bonding zone and for engaging and bonding said base portion to said heated longitudinal substrate area; and means for chilling the bonded assembly. 31. Apparatus according to claim 30, wherein said annular heating surface is adapted for stretching said limited longitudinal area relative to the remainder of said substrate. 32. Apparatus according to claim 30, including thermoplastic extruder means for effecting continuous direct transit therefrom of the thermoplastic fastener strip through a short distance to said bonding zone, so that in such short transit distance said fastener strip will retain substantial residual thermoplastic fusion temperature; and means for chilling and thereby solidifying and stabilizing said fastener profile portion of the transitting fastener strip, but leaving said base portion at sufficient residual fusion temperature to remain thermoplastic to said bonding zone for bonding to said substrate by the combined thermoplasticity of said base portion and the fusion promoting heated condition of said longitudinal area.