跳至主要内容

what will affect Fabric Shrinkage?

   Shrinkage is a parameter of testing textile fabrics to measure changes in length and width after washing, shrinkage failing materials are dimensionally unstable and they can cause de shaping and deforming of the garments or products made out of those materials, it is tested at various stages but important is to before cutting the fabric into further sewn products and after cutting and sewing prior to supplying the products to buyers and end users.
 
   The moisture absorption of fiber is the direct factor of fabric shrinkage. The tightness of yarn and fabric structure is the indirect factor of shrinkage. The tighter the structure, the expansion of the fiber cause the yarn to swell, then the warp height of the yarn in the fabric increases and the length of the yarn in the buckling state becomes shorter, so the fabric shrinks. Therefore, the higher twist and volume fraction of the yarn, the greater shrinkage of the fabric.

   The processing tension of the fabric also has an effect on fabric shrinkage. If the processing tension increases, the fiber deformation increases, the internal stress and the slow elastic deformation increase, then the relaxation and retraction degree of the fabric increases after soaking, which make the shrinkage rate of the fabric increases obviously. Besides, temperature also has a great effect on fabric shrinkage, because the high temperature has the effect of relaxation and expansion, and even heat shrinkage.

  Different raw materials of fabrics will affect shrinkage rate and heat shrinkage rate. Under normal circumstance, fabrics with minimum shrinkage rate are synthetic fibers and blended fabrics; secondary is linen fabrics; middle is cotton fabrics; the maximum is viscose fabrics. In addition to this, the shrinkage rate varies from fabrics density, the thickness of yarns, weaving, dyeing and finishing process. Different kinds of fabrics have been prescribed standard of shrinkage rate. In the process of dyeing and finishing, some processes like mercerization and preshrunk can reduce shrinkage rate. Synthetic fiber is easy to deform when heated, especially nylon fabrics, it shrinks more easily when heated, but it can improve its dimensional stability by hot setting.

-------------------------------------------------------------------
For more information about our testing instrument, please contact
·website:http://www.qinsun-lab.com/
· +86-21-6780 0179
· info@qinsun-lab.com
· or leave your comments below

评论

发表评论

此博客中的热门博文

Classfication Of The Textile Testing

Textile testing is the term for a whole series of tests that examine the physical, mechanical and chemical properties of textiles. These tests are sometimes done before a textile goes into widespread use, or they're done on textiles arriving from other countries for sale in US markets. Countries like the United States have established standards for what should and should not be in textile products. Tests can show whether companies making textiles are in compliance or not. Many textile tests have many types. Some of them are physical tests, in which a sample of textile material is examined closely for feel and appearance. Such tests are done on individual fibers or strands of material and on yarns, threads made of several fibers twisted together. Textiles are subjected to light and other elements to see how they react. Some of these tests are done in a weather-ometer, a machine that tests for weathering and lightfastness of textiles. It's basically an enclosed box. Textiles...
发表评论
阅读全文

How To Process The Elmendorf Tear Strength Test

The Elmendorf tear tester has been developed specially for the paper industry and is outstanding for simplicity of operation and high measurement accuracy. The exchangeable pendulum is equipped with a pneumatic sample clamp. The initiation and return of the pendulum, as well as sample cutting is completely automatic. The device is operated via an integrated touch screen, where the test method can be selected, specific settings can be adjusted, and, after the measurement, results and statistics can be  displayed.Each pendulum is supplied with the appropriate control weight so that, with the help of the service program, it can easily be checked for functionality and balance. The Elmendorf tear test Procedure:     Cotton fabric was taken.     Warp and weft direction of the fabric was identified.     Two strips were cut from the fabric in both directions having dimensions of 100 x 63.5 mm.     The sample was then fixed in the jaws of the ...
8 条评论
阅读全文

Synthetic Blood Penetration Tester for Medical Face Mask

  Features of Synthetic Blood Penetration Tester: 1. Mask fixture is metal human head mold, which can fully simulate the actual use state of the mask. 2. Metal human head mold can be rotated at a certain angle, which is convenient for sample clamping. 3. Specially designed injection control device, a certain volume of synthetic blood can be sprayed in the controlled time. 4. Instrument uses a gas source that can provide (700±25) kPa stable air pressure. 5. It can simulate the liquid injection velocity corresponding to the human blood pressure 10.6 kPa、16.0kPa 、21.3kPa (i.e .80 mmHg、120mmHg、160mmHg) for the test. 6. A fixed target plate is provided to block the high pressure edge part of the ejected liquid flow, only the steady flow part is sprayed on the area sample, which increases the accuracy and repeatability of the test. 7. This blood penetration testing equipment uses imported special aluminum wire drawing panel, equipped with metal keys, sensitive operation, not easy to dama...
发表评论
阅读全文