Why Texturizing is Done?
The continuous filament yarns are very smooth and do not have any air pockets due to which the apparels manufactured from such filaments feels uncomfortable. In texturising these filaments are made bulkier and crimped by inserting the crimps in the continuous filament yarn. Due to this air pockets are formed due to which it absorbs the moisture and makes feel comfortable.
Texturising is a procedure used to increase the volume and the elasticity of a filament or fibers.
The essential properties of textured yarns and the products made from them are softness, fullness, a high degree of elasticity, thermal insulation, and moisture transportation properties.
All yarns which can be shaped by heat are suitable for texturing. The most important texturing methods can be placed into six groups.
1. False Twist Texturising
Partially orientated yarn (POY) is fed into a heating zone (200-2300C), where the inserted twist is set.
The yarn then passes through a cooling zone to a twisted unit, consisting of a series of revolving discs, which insert twist.
When twisted yam is relaxed the yarn retains a thermal memory, which produces a yarn with a high bulk/stretch potential.
Bulk/stretch can be controlled by passing the yarn through a second heater.
2. Air-Jet Texturising
In this method of texturing, the yarn is led through the turbulent region of an air jet at a rate faster than it is drawn off on the far side of the jet.
In the jet, the yarn structure is opened, loops are formed, and the structure is closed again.
Some loops are locked on the surface of the yarn. An example of this method is the Taslan process.
3. Knit De-Knit Texturising
Knit-de-knit texturing is used on drawn fiber in order to produce crimp of a knitted-loop shape. In this process, the yarn is knitted into a tubular fabric, set in place by means of heat, and then unraveled to produce textured yarn.
4. Stuffer Box
The crimping unit consists of two feed rolls and a brass tube stuffer box. By compressing the yarn into the heated stuffer box, the individual filaments are caused to fold or bend at a sharp angle, while being simultaneously set by a heating device.
5. Gear Crimping
In this method, the filament is run between a pair of intermeshing gear wheels. The resultant yarn is left with the impression of the gear wheel teeth. Here the gear wheels are supplied with the source of heat due to which crimps are formed.
6. Edge Crimping Method
In this method of texturing, thermoplastic filaments in a heated and stretched condition are drawn over a crimping edge and cooled. Edge-crimping machines are used to make Agilon yarns.