Content area
Full Text
1. Introduction
Outdoor clothing requires high waterproof performance. The quality of waterproof garment largely depends on seam waterproof performance. Previous studies showed that waterproof performance could be achieved by waterproof fabrics and seam connection technology (Di et al., 2001; Prabir, 2011; Sakthivel et al., 2013). It was reported that joining was a critical step in the process of manufacturing thermoplastic composite products (Ahmed et al., 2006). The major defects in quality inspection are caused by seam connection technology such as air bubbles inside seam tape, seam tape edge peeling off, seam tape burnt or broken, etc. (Prabir, 2011).
At present, sewing-thermo adhesive tape sealing (S-TATS) has been widely used in outdoor garment. However, there are quality problems resulted from needle holes and thread such as seam leaking and excess shrinkage (Sakthivel et al., 2013; Vlad et al., 2013).
Ultrasonic welding (USW), which requires no needles or threads, was an alternative to S-TATS (Altaş and Pamuk, 2007). Compared with S-TATS technology, simplified procedures in USW process can finish cutting, sealing and continuous welding in one step by using rolling press foot (Volkow, 2009). Continuous USW can be used in tubular and three-dimensional parts such as sleeves, pants legs or continuous seams. There are lighter weight and fashion appearance in USW seams (Porav, 2013). The temperatures on USW welding area are lower than that counterpart of S-TATS (Suresh et al., 2007). Despite many advantages, the welding strength of clothing seam made by USW is weak, which is caused by insufficient or excessive welding.
Ultrasonic welding-thermo adhesive tape sealing (USW-TATS) is a new method used for joining waterproof fabrics in outdoor garment. This method can avoid the deficiency of S-TATS and USW technology by reducing shrinkage in USW process and improving the seam strength in TATS process. Na et al. (2013) reported the effects of the welding speed, seam sealing speed on the physical properties of seamed fabrics. However, the impact of amplitude and roller pressure of USW parameters is not reported, which should be further studied.
In order to obtain waterproof seam with high quality, many investigations focused on weld ability of materials. Gutnik et al. (2002) reported that thermoplastic material was most suitable for USW joining. Thermoplastic material can...