Components of a Zipper | Manufacturing Process of Zippers | Applications of Zippers

Posted by Default on December 25, 2018 in

Zipper is a closure or fastener that are normally used to make permanent and semi permanent connections between thegarment panels and joints that could be unfastened and fastened. It is a popular device for temporarily joining two edges of fabric. They are purely functional as well as decorative sometimes. The ‘zipper’ was introduced in 1893 at the Chicago World’s Fair then with the name of ‘Clasp Locker’. Initially, during the 1930s zippers were elements in children’s clothing for aiding them to dress themselves more easily. Zippers came into public interest in 1937 through the fashion designers in France who used them on men’s trousers. It is used in clothing, luggage, and other bags, sporting goods, camping gear, and other daily-use items. 

Objectives of a Zipper: 
The main objectives of zippers are 

1. To increase or decrease the extent of an opening to restrict or permit the passage of items.
2. To join or isolate two panels of a garment, as in front of a dress or skirt.
3. To detach or attach a detachable panel of the garment from another, as in the adaptation between trousers and shorts.
4. To decorate an item.

Components of a Zipper: 
The construction and components or parts of a zipper are shown in Figure-1. 

Figure-1: Components of a zipper (Image courtesy: wikipedia.com)

1 - Top tape extension 
2 - Top stop 
3 - Slider 
5 - Tape 
4 - Pull tab 
6 - Chain width 
7 - Bottom stop 
8 - Bottom tape extension 
9 - Single tape width 
10 - Insertion pin 
11 - Retainer box 
12 - Reinforcement film 

The bulk of a zipper includes tens or hundreds of precisely shaped plastic or metal teeth which are attached to two pieces of fabric tape. These teeth could be either individual or fashioned from an endless coil, known as elements. The slider moves alongside the rows of teeth which have to be operated manually. The Y-shaped network inside the slider interlocks or separates the opposing rows of zipper teeth, based on the direction of the slider’s movement. In zipper construction, either chain zippers where two sets of interlocking teeth are used or coil zippers where coils are used which are attached to a band of fabric tape. 

Zipper Size: 
Zippers are available in a range of sizes such as 3, 4, 5, 6, 7, 8, 9, 10, 12, etc., which are industry standards and does not imitate any dimensions of zipper, however, the larger the zipper size, the stronger the zipper. Zipper length denotes the length of the zipper among the topmost point of the top stop and the bottom most point of the bottom stop. 

Manufacturing Process of Zippers: 
The process sequence of zipper manufacturing is shown in Figure 13.7. 

Fig: Process sequence of zipper manufacturing

1. Weaving of textile fabric: The cotton or some other blended yarn in both warp and weft are normally used for weaving a narrow fabric in a needle loom to produce a woven edge braiding. The zipper must be processed through weaving, cutting and winding processes before the complete edge braiding of the zipper. 

2. Zipper chain forming: The resin (if it is polyester) is fed into the injection moulding machine to form a zigzag line. 

3. Zipper slide head and end stopper: Metal or aluminium alloy is fed into the die casting machine to produce a slider and end stopper with required size and shapes. 

4. Sawing and fitting: The fabric tape and zipper chain are attached together using a sewing machine. After that, the top and bottom stopper of the zipper and the slider are fitted and adjusted. 

Applications of Zippers: 
The common applications of zippers in different areas are given below. 

1. Ladies’ and children’s garments: Coil filler cord (CFC), coil without cord type (CH) or invisible zippers; mostly closed-end zippers are used.
2. Jackets and overcoats: Metal or moulded open end or two-way separating zippers.
3. Trousers: Three ladder type coil (LFC), CFC with auto lock, closed end zippers.
4. Denim and casual wear: Robust closed end metal zippers.
5. Luggage items: CFC is most commonly used. Zippers in long chain rolls and sliders are sold separately.

References: 

1. Apparel Manufacturing Technology by T. Karthik, P. Ganesan, D. Gopalakrishnan
2. Garment Manufacturing Technology Edited by Rajkishore Nayak and Rajiv Padhye