Sewing method to increase seam strength

Abstract

An improved garment seam with bonded fabric surfaces caused by the melting of at least one low-melt sewing thread that is used in conjunction with conventional high-melt sewing threads to construct the seam. The melted low-melt sewing thread acts like an adhesive to bond together the folds of fabric making up the seam. A sufficient amount of heat, and if necessary pressure, is applied to the seam which causes the low-melt thread to flow into the fabric interstices thereby creating a seam and permanently bonding the first and second garment components together along the seam to produce a stronger seam that is possible using stitches comprised of conventional high-melt sewing thread alone.

Description

BACKGROUND OF THE INVENTION [0001] My invention relates to an improved garment seam and method for making the seam. More specifically, the improved seam of my invention is bonded together with a molten polymer because the method of my invention uses a low melt sewing thread as one of the threads used to sew the seam. Upon heating the finished seam the low melt thread melts and bonds the garment fabric together. It also coats and bonds the conventional high melt sewing thread, which is sewn in conjunction with the low melt thread, to the fabric and thus prevents unraveling of the stitch. My invention can be used in any garment seam, including the side and French seams of a dress shirt or in trouser seams or in skirt hems or in any article made of fabric. [0002] Bonding of seams using molten polymers is known to the art of garment manufacturing, as exemplified by U.S. Pat. No. 6,079,343. This patent teaches the placement of an adhesive strip or tape inside the seam before the seam is ...

AI Technical Summary

Benefits of technology

[0005] It is therefore a general object of my invention to provide a garment seam, especially the side or French seam regions of a dress shirt or the hems on trousers or skirts, and a method for making the seam which will obviate or minimize difficulties of the type previously described.

[0007] It is another object of my invention to provide a pucker-free garment seam and a method of production of the seam which lowers RTM values.

Problems solved by technology

Unfortunately, the use of such an adhesive strip not only adds additional material cost to the manufacture of garments, it significantly increases the “standard minute value” associated with the manufacturing process.

Higher values translate directly into higher manufacturing costs.

Manufacturers work very hard to reduce the standard minute value associated with a particular garment's construction.

Another drawback when using the adhesive strip is the extra time it takes the sewing machine operator to position and align the strip in the seam.

Another limitation of the adhesive tapes or strips used in prior art processes is that when they melt the adhesive only bonds fabric to fabric.

There is no way for the molten polymer to coat the conventional high melt sewing threads used to stitch the seam, let alone cause these threads to bind directly to the seam fabric.

As such, the prior art tape cannot prevent or reduce “stitch run back,” which is one cause of high “return to manufacture” (RTM) values associated with a garment's manufacture.

Like the standard minute value, a high RTM is not desirable in that it results in increased cost to the manufacturer.

“Stitch run back” occurs when a stitch is missed during the sewing of a seam or hem and the stitch begins to unravel, thus causing the seam to fail.

Yet another disadvantage of the adhesive tape is the degree of difficulty in placing it in small diameter seams, such as in a French seam or a trouser seam.

Because of the stiffness of the tape, it is very difficult to align the tape to follow the tight radius of curvature of such seams without causing the tape to bunch.

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