A Zip is a commonly used device for binding the edges of an opening of fabric, bag, shoe and so on. The device was patented in 1893 by Witcomb B Judson, and he called it a 'clasp locker'. This design was improved by Gideon Sundback and applied it for sleeping bags, gloves, corsets, money belts, tobacco pouches etc. Goodrich used it in Zipper boots. By the 1930's "zipper" became a generic term applied to any toothed, slide fastener. Whatever the zip is, its weight (determined by its tape and structure weather coil or chain) should be compatible with that of the garment fabric.
A coil zip is a continuous synthetic strand made up of polyester or nylon twisted into a spiral and attached to a woven or knit synthetic tape. The coil zip is lightweight and more flexible and hence it is suitable for lightweight to medium fabrics.
A chain zip consists of individual teeth, generally metal attached to a cotton-blend or cotton tape. Chains are slightly more rigid and are suitable for medium to heavy fabrics as they can cause buckling on light weight fabrics.
Zips are of three basic types:
Conventional Zips are either chain or coil, are open at the top and are held together at the bottom. They are available in many different styles then any zip types. Used for necklines, dresses, skirts, trousers, jeans etc.
Concealed Zips are built differently from other zippers and are inserted in a special way so that they disappear into a seam (neither the zip coil nor the stitching is visible on the outside). These types of zippers are mainly used in dresses and skirts.
Open-End Zips open at both top and bottom, allowing the zip opening to separate completely. These are ideal for completely front opened apparels like jackets and cardigans.
