Patent Publication Number: US-2012042817-A1

Title: Method of joining fabric panels

Description:
The present invention relates to the joining of panels of fabric. Traditionally, fabric panels have been joined by sewing. More recently, chemical adhesion has been used to join panels. In some applications, a combination of these two techniques is employed. 
     One example of the use of a combination of sewing and panel adhesion can be found in the construction of a lapseam used to join fabric panels in garments such as ‘non-iron’ garments; for example shirts. A lapseam is constructed by interfolding two panels of fabric to create a seam having four layers of fabric and then creating two, parallel runs of stitching through all four fabric layers which extend along the edges of the seam. To ensure the seam is neat, flat, free from pucker and also to provide additional strength to the seam, it is known to place a fusible tape between two layers—typically the second and third layers—of the lapseam. When heat is applied to the seam, an adhesive coating on the tape melts and, the hot adhesive penetrates through the layers of the seam to add adhesive strength to it. 
     The insertion of the tape necessarily represents an additional step in the manufacture of apparel created using a lapseam and therefore represents an additional cost. One embodiment of the present invention provides an alternative. 
     According to an embodiment of the present invention there is provided a method of joining two panels of fabric comprising the steps of: placing the edges of the panels in register with each other to form a seam; wrapping the edge of at least one panel in fusible thread to create a treated edge; stitching the interfolded panels to join them to each other; and applying heat to the stitched seam to cause the fusible thread to melt. 
     A further embodiment provides a method of joining fabric panels comprising the steps of: overlock serging the ends of two fabric panels to create, on each panel, a treated edge; creating a lapseam by interfolding the treated edges of the two panels and then stitching the interfolded panels together; applying heat to the lapseam; wherein each of the treated edges is created by overlock serging using fusible thread. 
     Yet a further embodiment provides a method of joining panels of fabric including the steps of treating at least the edge of one of the panels by wrapping the edge in fusible thread, placing the panel edges adjacent each other and stitching the panels together by at least one run of stitching extending substantially parallel to the treated edge; pressing the treated edge against one of the panels and heating the edge thereby to melt the fusible thread. 
     In a preferred embodiment, after performance of a single stitching step resulting in the creation of a rib made up of the two parts of the panels lying beyond the stitching run, the panels are both folded back upon themselves to enclose the rib within a French seam and heat is then applied to the or each treated panel edge of the rib, with the folded-back panels being simultaneously pressed against each other and the other panels forming the French seam. 
     According to a further preferred embodiment, the first stitching run is performed simultaneously with the treatment of both panels of the rib by overlock stitching, with the serging of the rib edges being undertaken by fusible thread. 
     Yet further embodiments of the present invention provide a garment or other item of manufacture having two panels of fabric which are joined by a seam created by one or more of the embodiments of method disclosed herein. 
    
    
     
       Embodiments of the invention will now be described, by way of example, and with reference to the accompanying drawings in which: 
         FIG. 1  is a section through a prior art lapseam with fusible tape; 
         FIG. 2  is a plan view of the lapseam of  FIG. 1 ; 
         FIG. 3  is a perspective view of an edge of a fabric panel treated by overlock serging; 
         FIG. 4  is a perspective view of a treated fabric edge by simple thread looping; 
         FIG. 5  is a section through a lapseam according to an embodiment of the present invention; 
         FIG. 6  is a perspective view of an overlocked seam according to an embodiment of the present invention; 
         FIG. 7  is a section through an overlocked seam at a first stage in its creation according to an embodiment of the present invention; 
         FIG. 8  is a section through the overlocked seam at a further stage in its creation according to an embodiment of the present invention; 
         FIGS. 9 to 11  are perspective views of stages of joining two panels of fabric by means of a French seam according to an embodiment of the present invention; 
         FIGS. 12 and 13  are perspective views of stages of joining fabric panels according to a further embodiment of the present invention; and 
         FIG. 14  is a side view of a seam according to an embodiment of the present invention. 
     
    
    
     Referring now to  FIGS. 1 and 2 , two panels of fabric,  10 ,  12  are interfolded with each other to create a seam  14  which is four layers of fabric thick. The seam  14  therefore includes fabric layers  20 - 26  as shown in  FIG. 1 . The two panels  10  and  12  are joined by means of two runs of stitching  30 ,  32  (whose location is illustrated in  FIG. 1  by means of dashed lines). To ensure the seam is neat, flat, free from pucker and also provide additional strength, a fusible tape  40  is inserted between the second and third fabric layers  22  and  24  respectively of the seam  14 . The function of the tape  40  is to provide adhesive which, when heat is applied to the seam after stitching, melts and penetrates through the fabric layers of the lapseam to ensure a strong join between fabric panels  10  and  12 . Such a seam is entirely conventional. 
       FIG. 3  illustrates the use of what is known as overlock serging to treat the edge of a panel  50  of fabric and, thereby, to protect the edge of the panel from fraying. Referring to  FIG. 3 , the panel edge  52  is effectively wrapped in two interlooping threads,  54 A and  54 B, known as looper threads. The looper threads  54 A and  64 B traverse a cyclic path which: runs along the panel edge in opposite directions, where they interloop with each other at locations  56 ; then each looping thread  54 A,B loops rearwards (i.e. lateral to the panel edge) on opposite sides of the panel  50 ; there, the resultant rearwardly-extending loops  58 A and  58 B respectively are fastened to the panel  50  and, effectively, also to each other by means of a needle thread  60  which penetrates the loops  58 ; the looping threads  54 A, B then run back to the panel edge where they cycle is repeated. 
     This treatment of the edge of a fabric panel by wrapping it in looping threads prevents fraying and, when applied to a single panel of fabric as illustrated in  FIG. 3 , is known as ‘overlock serging’. The particular example of overlock serging shown in  FIG. 3  is overlocking stitch formation  504  according to British Standard BS3870:1991 or ISO4915: 1991, though any stitch formation which wraps the fabric panel edge, whether or not an overlocking formation and whether or not conforming to an established standard or otherwise—will achieve substantially the same effect. For example,  FIG. 4  illustrates treatment of a panel edge with a substantially simpler wrapping thread formation, which uses only a single, continuous looping thread. The term ‘looping thread’ is to be understood to apply to any thread whose function is to wrap or otherwise condition or treat the edge of a panel of fabric, regardless of the purpose for which such treatment is undertaken. 
     According to an embodiment of the present invention, two individual panels of fabric are joined together by a method in which the panel edges which it is intended to use to form a seam are first treated to prevent fraying by wrapping them with one or more looping threads which include fusible material; thereafter, the treated edges are then interfolded to create a lapseam which is then stitched in a conventional manner; heat is then applied to the stitched lapseam to cause melting of the fusible threads and, thereby, penetration of the resultant adhesive into the stitched lapseam. 
     Referring now to  FIG. 5 , two fabric panels  110  and  112  have edges  110 E and  112 E which are each treated by wrapping with a single looping thread (as shown in  FIG. 4 , but omitted from  FIG. 5  for the sake of clarity) of fusible material. Alternatively, the edges  110 E and  112 E can be treated by overlock serging and, indeed, any suitable edge treatment may be used. The treated edges of the panels  110  and  112  are interfolded to create a seam  114  which is four layers of fabric thick, comprising the layers  120 - 126 , each of which has been treated. The interfolded panels  110  and  112  of seam  114  are then fastened together by two separate, parallel runs of stitching  130 ,  132 . Thereafter, heat is then applied to the panels which causes the fusible seams to melt. That, in turn, causes the molten adhesive to penetrate through the layers of the seam which, when the adhesive has set, creates a seam which is neater, flatter, more free from pucker and significantly stronger than seams without adhesive. 
     In a further modification, the seam of  FIG. 5  can be constructed by treating only one of the edges  110 E or  112 E, whether by overlock serging or a single continuous loop or any other suitable edge treatment. 
     A seam of the kind illustrated in  FIG. 5  has a number of advantages over that of the prior art lapseam which employs a fusible tape. Firstly, is frequently the case that fabric panels used for the manufacture of apparel will, as a matter of course, have their edges treated by wrapping in looping threads. By performing this operation using fusible looping threads may, in certain circumstances, add no further steps to the process of creating a fusible lapseam. Secondly, where a fusible tape is employed in a lapseam which includes fabric panel edges that have been treated by looping threads, the resultant fusible lapseam can be very bulky and possibly also overly stiff for use in some apparel. 
     Referring now to  FIGS. 6 to 8 , in a modification of the present invention, an overlocked seam which joins two fabric panels  210  and  212  is created using two interlooping threads  254 A and B which are then fastened to the fabric panels by a needle thread  260 . In this example, the upper interlooping thread  254 A is made of conventional thread and the lower interlooping thread  254 B is made of fusible thread. Referring additionally to  FIG. 7 , after overlocking has been performed, the two panels  210  and  212  are now joined but a rib  270 , made up of the two, connected edges of the panels  210  and  212  depends laterally from the joined panels. In order to create a more robust and aesthetically pleasing join, the rib  270  is then folded to the right in  FIG. 7  so that it lies flat against panel  212 . The fusible interlooping thread  254 B now lies adjacent to the panel  212 . Heat is then applied to the seam with the result that thread  254 B melts and, as a result, the rib  270  adheres to the panel  212  to create a flat-lying overlocked seam without the need for additional topstitching (though additional top stitching may of course, be applied either to strengthen the seam further or for aesthetic purposes). 
     Referring now to  FIG. 9 , two panels of fabric  300 ,  310  which It is sought to join by means of a French seam are first placed adjacent each other such that two of their edges lie in register. A run  330  of stitching, lying substantially parallel to the fabric panel edges, is then created to fix the panels  300 ,  310  to each other. This results in the creation of a rib  370  made up of the fabric in each panel which projects beyond the stitching run  330 . As can be seen from  FIG. 9 , the edges  300 A,  310 A of the rib have a tendency to splay apart. 
     Referring now additionally to  FIG. 10 , the edges of the rib are then treated by wrapping both edges, simultaneously, in fusible thread  354 . The wrapping of the edges simultaneously has the collateral effect of binding the edges of the rib to each other, though this is not essential and, if for any reason it is preferred, the edges can be wrapped individually. In an alternative embodiment, only a single edge of the rib is wrapped. Equally, any thread pattern may be used Thus, the manner of wrapping displayed in  FIG. 10  is a simple looping thread pattern. Alternatively, the edges may be overlock serged. In one alternative embodiment, the two panels are overlock stitched, with the result that the run  330  is stitched simultaneously with the wrapping of the panels by fusible thread. 
     According to yet a further modification, one or both panel edges (since embodiments of the present invention may be put into practice using only a single treated panel edge) may be treated by wrapping (whether by overlock serging or in some other manner) prior to execution of the first stitching run. 
     Referring now to  FIG. 11 , the panels  300 ,  310  are then folded back, thereby to enclose the wrapped rib  370  and a further run  380  of stitching is then put in place, extending substantially parallel to the first run  330 . The rib  370  is now enclosed within a stitched French seam. 
     In accordance with one embodiment of the present invention, the seam is then subjected to heat to cause the fusible thread which wrapped the edges of the rib  370  to melt and, as the seam is then flattened, typically by ironing or a similar procedure so that the two treated edges are effectively folded against the panels. The melting adhesive is consequently then pushed into all four panels of the seam to provide added strength and a neater seam. 
     Yet a further alternative embodiment will now be described referring to  FIGS. 12 and 13 . Two panels  400 ,  410  are first of all joined together by overlock stitching. The panels are therefore joined by a run of stitching  430  from which a rib  470  then projects. Overlock stitching inevitably serges the edges of the rib  470  by wrapping the rib in fusible thread. This is achieved by two interlooping threads, one on either side of the rib  470  which are then, in effect, anchored by the thread of the stitching run  430 . In the illustrated example, a stitch pattern similar to overlock stitch type  504  is shown but any suitable stitch pattern may be employed. While, in accordance with one preferred embodiment, both of the interlooping threads are provided by fusible thread, this is not essential and it is possible to serge the rib using one fusible thread which interloops with a thread that is not fusible. 
     Referring now to  FIG. 13 , a part of the fabric in the region of the stitching run  430  is then folded around upon itself to create a roll of fabric  475 , The roll  475  includes the rib  470  and more mutually adjacent parts of the panels  400 ,  410  besides is configured such that the rib  470  lies flat, adjacent the panel  400 . Where only one of the interlooping threads is fusible, preferably the side of the rib which is serged with the fusible interlooping thread is the side which faces the panel  400 . Referring now additionally to  FIG. 14 , once roil  475  has been created, a further stitching run  480  is executed to create a French seam. This can, if desired, be supplemented by yet a further stitching run  490  (shown in  FIG. 13  to extend only part way along to illustrate its optional nature). The rib  470  is effectively folded against the panel  400  by the action of creating the second run  430  of stitching and, thereafter, heat is applied to the stitched seam to cause the fusible thread in the rib to melt and to penetrate through the folded fabric layers which create the french seam, thus adding strength and making the seam neater.