Abstract:
Disclosed herein is a seaming element for attachment to an industrial textile. The industrial textile has opposed first and second seamable edge regions, while the seaming element has: i) a first lateral edge; ii) a second lateral edge; iii) a trailing edge; iv) a forward portion comprising a plurality of protruding seaming with successive loops spaced apart by an aperture, and v) a rearward portion continuous with the forward portion, with the rearward portion comprising an upper member and a lower member. The upper and lower members are substantially planar and have mutually opposed inner surfaces, with a portion of each inner surface bonded to the industrial textile at a selected one of the first and second seamable edge regions. At least one of the upper and lower member comprises one or more slits between the first lateral edge and the second lateral edge, with the one or more slits extending from the respective trailing edge in a direction towards the forward portion of the seaming element.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a submission under 35 U.S.C. §371 for U.S. National Stage Patent Application of, and claims priority to, International Application Number PCT/CA2014/000072, entitled COMPLIANT SLIT FILM SEAMING ELEMENT, filed Jan. 30, 2014, which International Application is related to and claims priority to Canadian Application Serial No. 2,805,366, entitled COMPLIANT SLIT FILM SEAMING ELEMENT, filed Feb. 7, 2013, the entirety of all of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present specification relates to seaming elements used to form a seam in woven or nonwoven industrial fabrics. In particular, it relates to seaming elements that are compliant or flexible in the plane of the fabric to provide secure attachment between the seaming element and the fabric. 
     BACKGROUND 
     Industrial textiles for use in filtration, separation and conveying applications such as papermaking have been in use for many years. The vast majority of these fabrics are typically woven from polymeric yarns such as monofilaments using large industrial looms. Following weaving, the textiles are further processed for use in particular applications. At this point, a seam is usually installed so that the fabrics may be joined on the machine for which they are intended. Many seam constructions are known and have been used; however, most require a significant amount of highly specialized personnel and/or machinery. For such woven textiles, the fabric ends must first be prepared so as to free a portion of the component yarns from the woven structure; these yarns are then either rewoven with yarns from the opposite end to form a woven seam, or they are interlaced in one of various ways with seam devices which accept a joining pin or pintle, such as coils and the like. These seam constructions are costly and time consuming to prepare. Similar disadvantages of time and cost apply to nonwoven industrial textiles, such as those constructed from one or more layers of film. 
     WO 2010/121360 (Manninen) discloses a seaming element that can be attached to each of the two opposed fabric ends, thereby forming a seam in an industrial textile. The textile is typically cut straight across its width perpendicular to the intended running direction of the finished fabric. The seaming element is then bonded either over, or between, layers of the component yarns or film. The bonding method may include through transmission laser welding (TTLW). After the seaming element is bonded in position, the finished fabric is ready for installation on the machine for later use. The seaming element varies from 0.5 m to 6 m in length, and is made from a polymeric material. In one embodiment, the seaming element has a U-shape, which is slipped over each end of the prepared fabric and welded in place. 
     Other types of seaming element have been disclosed. For example, WO 2011/069258 (Manninen et al.) discloses a hinge type seaming element; PCT/CA2012/000701 (Manninen) discloses a fold-over type seaming element; PCT/CA2012/001138 (Manninen) discloses a multi-pin seaming element; and WO/2014/075170 (Manninen) discloses a roll formed seaming element including ridges. 
     U.S. Pat. No. 5,182,933 (Schick) and U.S. Pat. No. 4,942,645 (Musil) each disclose a fastener for securing the ends of belts, comprising upper and lower members that are connected at one edge by multiple arcuate loops that are separated by apertures. On the opposite edge, the fastener contains a series of webs that are riveted to the belt. 
     U.S. Pat. No. 4,719,788 (Musil) and Flexco®SR™ Rivet Hinged R9 Belt Fastener each disclose belt fasteners comprising an upper plate, a lower plate and loop shaped strap means for joining these plates. The upper or lower plate of these fasteners can be connected to the same plate of an adjacent fastener at rupturable bridges to form a fastener strip. 
     U.S. Pat. No. 6,216,851 (Mitas et al.) discloses a belt fastener element having upper and lower plates connected by arcuate hinge loops. Further, the lower plates are connected in a continuous manner while the upper plates are spaced apart. 
     It will be appreciated that during the bonding process, particularly when a TTLW bonding process is used, a reliable and high strength bond should be formed between the seaming element and the fabric component. TTLW requires intimate contact between the joining components in order to form a high strength bond. This can be difficult to achieve when a relatively large, solid object (such as the seaming element) is being bonded to relatively smaller and discrete units, such as the polymeric monofilament yarns of a woven fabric. Such yarns are often crimped and do not necessarily present a uniform, planar surface for welding. Similarly, nonwoven fabrics often have discontinuities and nonplanar irregularities, thereby reducing the necessary intimate contact between the seaming element and the nonwoven fabric. 
     It would be advantageous to render the bonding region of seaming elements flexible or compliant so that, during a bonding process, intimate contact can be made between the fabric components and the seaming element. 
     In addition, where a nonwoven textile is used, it would be advantageous to modify the attachment of the seaming element to the fabric so that the strength of the bond between the seaming element and the nonwoven textile is enhanced. 
     SUMMARY 
     Disclosed herein is a seaming element for attachment to an industrial textile. The seaming element will be first described in its general form, and then its implementation in terms of specific embodiments will be detailed thereafter. These embodiments are intended to demonstrate both the principle and optional features of the seaming element, and the manner of its implementation. The seaming element in its broadest and more specific forms will then be further described, and defined, in each of the individual claims that conclude this specification. 
     In one aspect of the present invention, there is provided a seaming element for an industrial textile, the industrial textile having opposed first and second seamable edge regions, the seaming element having: i) a first lateral edge; ii) a second lateral edge; iii) a trailing edge; iv) a forward portion comprising a plurality of protruding seaming loops with successive loops spaced apart by an aperture, and v) a rearward portion continuous with the forward portion, the rearward portion comprising an upper member and a lower member, the upper and lower members being substantially planar and having mutually opposed inner surfaces, with a portion of each inner surface bonded to the industrial textile at a selected one of the first and second seamable edge regions, wherein at least one of the upper and lower member comprises one or more slits between the first lateral edge and the second lateral edge, the one or more slits extending from the respective trailing edge in a direction towards the forward portion of the seaming element. 
     The seaming element and the industrial textile may each independently comprise a polymer; the polymer may be a thermoplastic. In addition, the seaming element may comprise a bi-axially oriented polyester. 
     Each of the upper and lower members of the seaming element may be bonded to the seamable edge region by a bonding method selected from the group consisting of: chemically reactive systems, adhesives, laser beam welding and ultrasonic welding. Furthermore, the seaming element may be bonded to the seamable edge region by through transmission laser welding (TTLW). 
     Each of the one or more slits may have a substantially linear configuration and may extend substantially normal to the respective trailing edge. In addition, the one or more slits may be evenly spaced between the first lateral edge and second lateral edge. Alternatively, the one or more slits may be randomly spaced between the first lateral edge and second lateral edge. At least one slit may be centrally aligned with one aperture. 
     In addition, at least one slit may extend partially through a thickness of the respective member, or may extend completely through a thickness of the member. 
     Where each of the upper and lower members comprises one or more slits, each of the one or more slits may be centrally aligned with a selected one of the apertures. In addition, each slit of the upper member may be aligned with a selected one of the slits of the lower member, and each slit of the lower member may be aligned with a selected one of the slits of the upper member. Alternatively, each slit of the upper member may be symmetrically laterally offset from an adjacent pair of slits of the lower member. 
     In another aspect of the present invention, there is provide a seaming element for an industrial textile, the industrial textile comprising a first polymer and having opposed first and second seamable edge regions, the seaming element comprising a second polymer and having: i) a first lateral edge; ii) a second lateral edge; iii) a trailing edge; iv) a forward portion comprising a plurality of protruding seaming loops with successive loops spaced apart by an aperture, and v) a rearward portion continuous with the forward portion, the rearward portion comprising an upper member and a lower member, the upper and lower members being substantially planar and having mutually opposed inner surfaces, with a portion of each inner surface bonded to the industrial textile at a selected one of the first and second seamable edge regions, wherein the upper and lower member each comprise a plurality of slits regularly spaced between the first lateral edge and the second lateral edge of the member, each slit extends from the respective trailing edge in a direction towards the forward portion of the seaming element; and each slit is centrally aligned with one of the apertures. 
     In the aforementioned seaming element, each slit of the upper member may be symmetrically laterally offset from an adjacent pair of slits of the lower member. 
     In addition, the industrial textile may comprise a thermoplastic; the seaming element may comprise a bi-axially oriented polyester; and the seaming element may be bonded to the seamable edge by a welding method selected from the group consisting of through transmission laser welding and ultrasonic welding. 
     In yet another aspect of the present invention, there is provided an industrial textile having opposed first and second seamable edge regions, each seamable edge region bonded to any one of the seaming elements described above. 
     In yet a further aspect of the present invention, there is provided a method of providing a seam to at least one seamable edge region of an industrial textile comprising: a) placing the industrial textile within any of the seaming elements described above; and b) bonding each of the upper and lower members of the seaming element to the seamable edge. 
     In the aforementioned method, the seaming element and the industrial textile may each independently comprise a polymer material; and the upper and lower members of the seaming element may each be bonded to the seamable edge by a bonding method selected from the group consisting of: chemically reactive systems, adhesives, laser beam welding and ultrasonic welding. The polymer material may be a thermoplastic and the bonding method may be through transmission laser welding. 
     The seaming element may comprise a polymeric material; the polymeric material may be a thermoplastic or thermoset material. Where the seaming element comprises a thermoplastic, the thermoplastic may be a bi-axially oriented thermoplastic, or a bi-axially oriented co-extruded material that can be welded by a laser. Herein, “bi-axially” implies orientation in both the machine direction (MD) and transverse direction (TD) of the thermoplastic material, such as a film. 
     The industrial textile may comprise a polymeric material; the polymeric material may be a thermoplastic or thermoset material. 
     Herein, the term “bonding” refers to the use of any one of: i) a chemically reactive system; ii) an adhesive; or iii) a welding process to attach two surfaces together. The welding process can include ultrasonic welding or laser beam welding, in particular through transmission laser welding (TTLW). 
     Where TTLW is used, both the seaming element and the industrial textile comprise a thermoplastic; the thermoplastic may comprise a polyester (for example, but not limited to, polyethylene terephthalate, or PET). In addition, where TTLW is used, the seaming element and/or the seamable end of the industrial textile include a radiant energy absorbent in order to allow for TTLW to bond the sealing element to the fabric. 
     Appropriate polymeric materials which are amenable to welding and would be appropriate for use as either yarns or films in both seaming elements and industrial textiles include, but are not limited to, polyethylene terephthalate (PET), hydrolysis stabilized PET, polybutylene terephthalate (PBT), polyethylene, polyethylene naphthalate (PEN), polypropylene (PP), polyphenylene sulphide (PPS), polyether ether ketone (PEEK) and other polymers such as would be appropriate for use in forming monofilament or film intended for use in industrial textiles such as paper machine clothing, including papermakers&#39; dryer fabrics and the like. Various nylon polymers, such as polyamide 6, polyamide 6/6, polyamide 6/10 and the like, as well as their copolymers and blends thereof, may also be appropriate materials. These materials are all suitable for laser welding. 
     Both the seaming element and the industrial textile may also comprise thermoset plastics such as either linear or aromatic heterocyclic polyimides made from Apical™, Kapton™, UPILEX™, VTEC™ PI, Norton™ TH and Kaptrex™ for example. These materials are available as films and are not suitable for laser welding; textiles comprising these materials must therefore be joined to the seaming element by means of an adhesive, chemically reactive system or other suitable bonding methods. 
     Where the seaming element is joined to the industrial textile by through transmission laser welding (TTLW), an energy absorbent material must be located at the interface between the parts to be welded. This material can be applied as a liquid to one or both parts, or may be located as a solid in film or filament form between the parts. Suitable energy absorbents include carbon black, or dyeable products such as Clearweld® (available from Gentex Corporation of Carbondale, Pa.) or Lumogen® (available from Basf Corporation). The seaming element may be made from a bi-axially oriented, co-extruded material film including: i) a first thermoplastic polymer that is effectively transparent to laser energy; and ii) a second thermoplastic polymer that includes a suitable laser energy absorbent material additive. 
     In such a construction, the transparent film layer is made sufficiently thin such that there is no undue attenuation of the radiation so that sufficient radiation is transmitted through to the second layer so as to melt it through its thickness to provide the necessary weld. For example, if the overall thickness of the co-extruded film ranges from 100 μm to about 500 μm, and the thickness of the energy absorbent layer is 5%-15% of this total, then the thickness of the transparent layer must be between from 85-95 μm (for total film thickness of 100 μm) and 475-425 μm (for thickness 500 μm). 
     One second layer, which is co-extruded with and joined with the first to form a single structure, comprises a second film or filament forming thermoplastic polymer which is capable of forming a sufficiently strong bond with the first polymer in the first layer so as to minimize depolymerization at the locus of subsequent welds. The second polymer may, but need not, be the same as the first, but should be at least partially miscible and compatible, with the first polymer forming the first layer, and may have a similar melt viscosity and melt temperature to that of the first polymer. The first and second polymers may be the same; in addition, the first and second polymers may both be polyesters such as, but not limited to, PET. Where polyesters are used, they are preferably hydrolytically stabilized so as to resist depolymerization, and are provided at an intrinsic viscosity of at least 0.5 or more. 
     The second polymer contains a suitable laser energy absorbent material additive which may be uniformly incorporated into and dispersed within the polymer during a melt blending process and is present in an amount sufficient to render the second film layer weld-enabling during a subsequent TTLW process. A particularly suitable additive may be carbon black; however, other additives such as clear or dyeable products e.g. Clearweld® (available from Gentex Corporation of Carbondale, Pa.) or Lumogen® (available from Basf Corporation) may also be suitable, depending on the intended end use. Appropriate amounts of the additive will depend on the additive selected, but where the additive is carbon black, it may be present in amounts ranging from about 0.1% pbw to about 1.0% pbw (parts by weight) based on the total weight of the second polymer 
     The foregoing summarizes the principal features of the seaming element and some of its optional aspects. The insert may be further understood by the detailed description of the embodiments which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first embodiment of a seaming element. 
         FIG. 2  is a top view of the seaming element shown in  FIG. 1 . 
         FIG. 3  is a rear view of the seaming element of  FIG. 1 . 
         FIG. 4  is an enlarged partial rear view of the seaming element of  FIG. 3 . 
         FIG. 5  is a side view of the seaming element shown in  FIGS. 1 to 4 . 
         FIG. 6  is a perspective view of a second embodiment of a seaming element. 
         FIG. 7  is a top view of the seaming element shown in  FIG. 6 . 
         FIG. 8  is a rear view of a third embodiment of a seaming element. 
         FIG. 9  is a rear view of a fourth embodiment of a seaming element. 
         FIG. 10  is a rear view of a fifth embodiment of a seaming element. 
         FIG. 11  is a perspective view of a sixth embodiment of a seaming element. 
         FIG. 12  is a top view of the seaming element shown in  FIG. 11 . 
         FIG. 13  is a rear view of the seaming element of  FIG. 11 . 
         FIG. 14  is a side view of the seaming element shown in  FIGS. 11 to 13 . 
         FIG. 15  illustrates a schematic for various slit arrangements in a seaming element 
         FIG. 16  is a perspective view of the seaming element of  FIG. 1  during a roller type laser operation. 
         FIGS. 17 a  and 17 b    illustrate sequential steps for the placement of slits onto a seaming element attached to a fabric. 
     
    
    
     DETAILED DESCRIPTION 
     Wherever ranges of values are referenced within this specification, sub ranges therein are intended to be included within the scope of the disclosure unless otherwise indicated. Where characteristics are attributed to one or another variant, unless otherwise indicated, such characteristics are intended to apply to all other variants where such characteristics are appropriate or compatible with such other variants. 
     The following is given by way of illustration only and is not to be considered limitative. Many apparent variations are possible without departing from the spirit and scope of the invention. 
       FIGS. 1 to 5  illustrate a first embodiment of a seaming element. Referring first to the perspective view in  FIG. 1 , seaming element  100  has top member  120 , bottom member  121 , first lateral edge  122 , second lateral edge  124 , leading edge  126  and trailing edge  128 . Seaming element  100  further includes along its leading edge  126  a plurality of protrusions  150  between which are located apertures  152 . Apertures  152  and protrusions  150  are dimensioned such that protrusions  150  on a first seaming element  100  will fit into and interdigitate with corresponding apertures  152  and protrusions  150  on a second seaming element  100 . In this manner, the two interdigitated seaming elements provide an interior channel to accommodate a conventional seaming member, such as a joining wire or pintle (not shown), to close the seam. Apertures  152  extend into the body of seaming element  100  to allow corresponding protrusions  150  from the second seaming element to be located in the desired position within these apertures  152 . 
     Seaming element  100  includes a plurality of regularly spaced longitudinal slits  110 , each of which is arranged perpendicularly to trailing edge  128  along both top member  120  and bottom member  121 . While the slits ( 110 ) are illustrated as being perpendicular to the trailing edge ( 128 ), it is understood that other orientations are possible. Furthermore, the slits may be randomly spaced. In addition, it is possible to have slits on one or both members ( 120 ,  121 ). These variations are discussed below. Slits  110  extend from trailing edge  128  inwards a selected distance towards leading edge  126 . Slits  110  extend through the thickness of the respective one of top member  120  and bottom member  121 . In other embodiments (discussed below) the slits may extend partially through the thickness of the member. 
     As seen in  FIGS. 1 through 5 , the slits in top member  120  are located in alternating, offset relation to those in bottom member  121 . Top and bottom members  120 ,  121  of seaming element  100  are thus evenly divided into a plurality of compliant tabs  111  located between and separated and defined by the slits  110 . In this embodiment, slits  110  are aligned with the centre of every second aperture  152  in each of top and bottom members  120 ,  121 , as shown more clearly in  FIG. 4 . It should be noted that the slits may be aligned away from the centre of the aperture in other embodiments. Thus, every tab  111  has a width equal to the distance between two apertures  152  and two protrusions  150 , as is shown more clearly in  FIG. 2 . 
       FIG. 2  is a top view of top member  120  of seaming element  100 , showing slits  110   a  and compliant tabs  111   a  ( FIG. 3 ). In  FIGS. 2-5 , the tabs and slits of the upper member are denoted by ‘a’, while those of the lower member are denoted by ‘b’. Slits  110   a  are regularly spaced apart from each other, are each of the same length, and each is located to be aligned with every second aperture  152  in element  100 . 
       FIG. 3  is a rear view of seaming element  100  shown in  FIGS. 1 and 2 , taken towards trailing edge  128  and showing slits  110   a  in top member  120  arranged in staggered relation to corresponding slits  110   b  in bottom member  121 . Slits  110   a  and  110   b  provide compliant tabs  111   a  and  111   b  in each of top and bottom members  120 ,  121 . An enlarged area of part of seaming element  100  is shown in greater detail in  FIG. 4 . 
       FIG. 4  is an enlarged partial rear view of seaming element  100  as shown in  FIG. 3 , showing tabs  111   a  in top member  120  and  111   b  in bottom member  121 . Between top member  120  and bottom member  121 , are protrusions  150 , located between respective ones of slits  110   a  and  110   b . These slits are aligned with the centre of the respective apertures  152 . 
       FIG. 5  is a side view of seaming element  100  shown in  FIGS. 1 to 4 , showing first lateral edge  122 , which is identical to second lateral edge  124  (see  FIG. 1 ). In  FIG. 5 , leading edge  126  including representative protrusion  150 , trailing edge  128 , top member  120  and bottom member  121  of seaming element  100  are shown. Seaming element  100  has a generally “U” shaped configuration when viewed from either first or second lateral edge  122  or  124 . 
     Referring to  FIGS. 6 and 7 ,  FIG. 6  is a perspective view of a seaming element  200  constructed and arranged according to a second embodiment, in which like parts have the same numbering as in the first embodiment, shown in  FIGS. 1 to 5 .  FIG. 7  is a top view of seaming element  200 . Seaming element  200  includes top member  120 , bottom member  121 , first lateral edge  122 , second lateral edge  124 , leading edge  126  and trailing edge  128 . 
     In this embodiment, each of the regularly spaced slits  210  in each of top and bottom members  120 ,  121  is aligned with the centre of every aperture  152 . Here, slits  210  in top member  120  are each aligned with slits  210  in bottom member  121 , thereby providing a plurality of compliant tabs  211 , in each of top and bottom members  120 ,  121 . Tabs  211  each have a width equal to the total width of one aperture and one protrusion. 
     It is not necessary that each of the top member  120  and bottom member  121  be provided with the same pattern of slits and tabs. The slitting pattern shown in  FIGS. 1 to 5  for example, may be provided to bottom member  121  while top member  120  is configured as shown in  FIGS. 6 and 7 . Other combinations of slitting patterns for each of top and bottom members  120 ,  121  are possible, and can be selected according to various factors, such as the intended end use of the textile in which the seaming element will be used, and the materials of construction. 
     The slits may be provided to seaming elements having any desired configuration for the forward portion adjacent to the leading edge, and to various configurations for the top and bottom members in the region adjacent the trailing edge. Such configurations would include, but not be limited to, those of the seaming elements of the prior art discussed above. 
       FIG. 8  illustrates an embodiment of a seaming element ( 300 ) in which the slits ( 310   a ,  310   b ) are randomly spaced along the width of the respective member ( 120 ,  121 ). In  FIG. 8 , like parts have the same numbering as shown in  FIGS. 1 through 5 . Therefore, compliant tabs  311   a  have unequal widths; the same applies for compliant tabs  311   b . Furthermore, while slits  310   a  and  310   b  are aligned with the centre of selected apertures  152 , the distance between successive slits  310   a  differs from that between successive slits  310   b.    
       FIG. 9  illustrates an embodiment of a seaming element  400  that includes partial slits ( 410   a ,  410   b ) in each of the upper and lower members ( 120 ,  121 ).). In  FIG. 9 , like parts have the same numbering as shown in  FIGS. 1 through 5 . Slits  310   a  and  310   b  extend part way through the thickness of the respective members  120  and  121 . Such partial slits allow for any of the compliant tabs  411   a ,  411   b  to become detached from those adjacent so as to follow the surface contours of the textile to which the seaming element is attached. As in the other embodiments, the compliant tabs ensure intimate contact between the textile surface and the seaming element during a TTLW process. 
     While partial slits  410   a  are in an alternating offset relation to partial slits  410   b , and are aligned with the center of every second aperture  152 , it is understood that the placement of the partial slits can take on any regular pattern or randomized placement as previously described. 
       FIG. 10  shows an embodiment of a seaming element ( 500 ) in which the slits  510   a  are provided on only one member ( 120 ) of the element. Seaming element  500  includes a plurality of regularly spaced longitudinal slits  510   a  arranged perpendicularly to the trailing edge of the seaming element and along top member  120 . As with the previous embodiments, slits  510   a  can have a regular pattern across the width of the element, or can be placed randomly. In addition, slits  510   a  may be partial (as shown in  FIG. 9 ). Bottom member  121  does not contain any slits. 
       FIGS. 11 to 14  illustrate another embodiment of a seaming element  800  which has an edge region  25   a  in top member  820 , and corresponding edge region  25   b  (shown in  FIG. 14 ) in bottom member  821 . Edge regions  25   a ,  25   b  are located in opposed parallel relation so that ridge regions  30   a ,  30   b  formed between shoulders  35   a ,  36   a , and  35   b ,  36   b  respectively are located directly above one another in seaming element  800 . 
     Seaming element  800  includes top member  820 , bottom member  821 , first lateral edge  822 , second lateral edge  824  (see  FIG. 12 ), leading edge  826  and trailing edge  828 . Seaming element  800  further includes along leading edge  826  a plurality of protrusions  150  between which are located apertures  152 , to provide for the joining of opposing pairs of seaming elements in the manner described above in relation to the previous embodiments. 
     In this embodiment, seaming element  800  includes a plurality of regularly spaced longitudinal slits  810  arranged perpendicularly to trailing edge  828  and provided to top member  820  and bottom member  821 . Slits  810  extend from trailing edge  828  inwards through edge region  25   a  (and corresponding edge region  25   b  on bottom member  821 , shown in  FIG. 14 ) a selected distance towards leading edge  826 , which distance extends through shoulders  36   a ,  36   b . Slits  810  in top member  820  extend through the thickness of the respective one of top member  820  and bottom member  821 , and slits  810  in top member  120  are located in alternating, offset relation to those in bottom member  821 . Top and bottom members  820 ,  821  of seaming element  800  are thus evenly divided into a plurality of compliant tabs  811  located between each slit  810 , which are aligned with the centre of every second aperture  152  on each of top and bottom members  820 ,  821 , as is shown most clearly in  FIG. 12 . Tabs  811  thus have a width equal to the distance between two apertures  152  and two protrusions  150 . 
       FIG. 12  is a top view of top member  820  of seaming element  800 , showing slits  810  and compliant tabs  811 . Top member  820  includes shoulders  35   a ,  36   a  located on either side of ridge region  30   a , and is shaped so as to be essentially identical to bottom member  821  except that slits  810  are located in offset relation to corresponding slits  810  in bottom member  821 . Slits  810  are regularly spaced from each other, are each of the same length, and each is aligned with every second aperture  152  in seaming element  800 . 
       FIG. 13  is a rear view of seaming element  800  shown in  FIGS. 11 and 12 , taken towards trailing edge  828  and showing slits  810  in each of top member  820  and bottom member  821 , slits  810  in top member  820  being offset in relation to corresponding slits  810  in bottom member  821 , to provide compliant tabs  811  in each of top and bottom members  820 ,  821 . 
       FIG. 14  is an end view of seaming element  800 , showing first lateral edge  822 , and second lateral edge  124  (see  FIG. 11 ). In  FIG. 14 , leading edge  826  including representative protrusion  150 , trailing edge  828 , and top and bottom members  820  and  821  including regions  25   a  and  25   b  are shown. Seaming element  800  has a generally “U” shaped configuration when viewed from either first or second edge  822  or  824  and includes shoulders  35   a ,  35   b ,  36   a  and  36   b  and ridge regions  30   a  and  30   b.    
     Independent variations of the positioning, depth and orientation of the slits is shown schematically in  FIG. 15 , in which a seaming element ( 860 ) having protrusions ( 150 ) and apertures ( 152 ) may have various combinations of slit orientations and arrangements in the upper and/or lower member ( 120 ,  121 ). The slit arrangements, as depicted by S 1  and/or S 2  may have the following independent features: the slit arrangements may be perpendicular to the leading edge, slanted, or have other orientations; may extend partially through the respective member, or extend fully through; may have regular or randomized spacing along the breadth of the member; and may be aligned centrally with selected apertures, or aligned in a position away from the central portion of selected apertures. Where slits are placed on both upper and lower members, the slit arrangement as depicted by S 1  may be independent of that depicted by S 2 . Alternatively S 1  and S 2  may be coordinated in any manner. For example, the arrangements S 1  and S 2  may be identical, or the slit arrangements may be offset relative to each other. 
       FIG. 16  is a schematic perspective representation of a seaming element  100 , during a roller type TTLW operation, during which a roller head R of a laser welding tool ( 875 ) is passed over tabs  111  in sequence under pressure.  FIG. 16  shows the compliancy of the tabs  111  due to the slits  110  in the element. This compliancy assures, to the greatest extent possible, an intimate contact between the surfaces of the tabs and the fabric to which the seaming element is to be welded in, for example a through transmission laser welding process. The roller type laser operation shown in  FIG. 16  applies to other variations of the seaming element, as shown, for example, in  FIGS. 6 through 14 . 
       FIG. 17 a    shows a seaming element  910  without any compliant tabs or slits, which has been attached in an earlier bonding or TTLW process to a first seamable end of an industrial textile  900 . Following attachment to the textile  900 , slits  110  are placed onto the seaming element  910 . Laser tool  920  (which is different from that used in a TTLW process) can be used to cut slits  110  in one or both members of the seaming element. The laser tool  920  can be, for example a CO 2  laser. The process is carried out as follows: the textile  900  and attached seaming element  910  are laid flat; the laser tool  920  is brought into position and adjusted to cut one or more slits  110  of desired thickness through the surface of one or both members of the seaming element. The laser tool  920  can be adjusted such that the slit  910  extends either partway, or completely through the surface of the seaming element. The position of the slits  110  can be made regular or randomized in the manner previously described. After the desired number of slits have been cut into one surface of the element, if desired, both the seaming element and the textile to which it is attached are turned over and the cutting process is repeated on the second surface. In this manner, the seaming element can be provided with a plurality of compliant tabs on one or both members. 
     Where the textile  900  is nonwoven (for example, a film), the slits  110  can extend completely through both the seaming element  910  and textile  900 . In this case, there is no need to turn over the assembled seaming element and film in order to make slits on the second member. As with the nonwoven textile, the position of the slits  110  can be made regular or randomized in the manner previously described. 
     Slitting the seaming element  910  following its attachment to the seamable edge of a textile  900  will not affect its compliancy. However, it will change the fracture mechanics and stress distribution of the bonded/welded area, particularly when attached to a nonwoven film type textile. This is because the slits imparted to both the element  910  and the nonwoven textile  900  will cause applied stresses to be distributed in a manner somewhat similar to that found in a comparable weld or bond onto a woven structure. By slitting both the seaming element  910  and a nonwoven textile material  900  following bonding, the resulting join is now able to distribute stress over a plurality of discrete fabric components, rather than a continuous sheet or film, and may thus evidence a higher strength and improved durability. 
     CONCLUSION 
     The foregoing has constituted a description of specific embodiments showing how the device may be applied and put into use. These embodiments are only exemplary. The device in its broadest, and more specific aspects, is further described and defined in the claims which now follow.