Dimensional Stability of Underwear Affected—Shrinkage Rate of Fabric

As intimate clothing, the comfort and dimensional stability of underwear are of crucial importance to consumers. The shrinkage rate of underwear fabric is one of the important indicators for measuring its dimensional stability. This article aims to discuss the standards and test methods of the shrinkage rate of underwear fabric and how to effectively reduce the shrinkage rate, so as to provide consumers with better quality underwear products.

I. Standards for shrinkage rate of underwear fabric

The standards for shrinkage rate of underwear fabric vary depending on the material, usage and national or regional standards. Generally speaking, the shrinkage rate of natural fibers such as cotton and linen is relatively high, while that of chemical fiber fabrics is relatively low. According to the international standard ISO 5077:1984 "Determination of shrinkage and elongation under wet and hot conditions for yarns and fabrics", the shrinkage rate of cotton knitted underwear should not exceed 5%. However, in practical applications, different countries and regions may have more specific standards. For example, in China, the shrinkage rate standard of underwear fabric may be adjusted according to factors such as fabric types and production processes, but in general, it needs to be controlled within a reasonable range to ensure the wearing comfort and dimensional stability of underwear.

II. Test methods for shrinkage rate of underwear fabric

There are various test methods for the shrinkage rate of underwear fabric, but generally follow the following basic principles:

1. Sample preparation: Cut representative samples from underwear fabric, ensure that the samples are free of defects, yarn ends and surface fuzz, and keep them dry before testing.

2. Pretreatment: Place the sample under specific temperature and humidity conditions (such as 20°C to 25°C, relative humidity 65% to 75%) to reach an equilibrium state. This step helps to eliminate the dimensional changes of the sample due to environmental differences.

3. Washing and drying: Wash the sample according to the standard or customer requirements using a specific washing program and equipment. After washing, the sample needs to be dried under standard conditions to ensure the accuracy of the test results. Commonly used drying methods include natural drying, dryer, etc.

4. Dimension measurement: Use accurate measuring tools (such as a steel ruler) to measure the size of the sample after washing and drying. To ensure the reliability of the results, multiple measurements are usually taken on each sample and the average value is taken.

5. Calculate the shrinkage rate: Calculate the shrinkage rate according to the measurement results. The formula is "shrinkage rate = (original size - size after washing) / original size × 100%".

In addition, there are auxiliary test methods such as immersion method and drying method. These methods can be flexibly selected according to fabric characteristics and test requirements.

III. How to reduce the shrinkage rate of underwear fabric

Reducing the shrinkage rate of underwear fabric is one of the key measures to improve product quality. The following are some effective methods to reduce the shrinkage rate:

1. Choose high-quality fabric: High-quality fabrics are usually pre-shrunk, and their shrinkage rates are relatively low. When purchasing fabrics, products that have been pre-shrunk and whose shrinkage rate meets the standard should be given priority.

2. Reasonably design the production process: In the fabric production process, by optimizing process parameters such as weaving and dyeing and finishing, the shrinkage rate of the fabric can be effectively reduced. For example, adopting appropriate tension control, temperature control and other measures can reduce the dimensional changes of the fabric during the processing.

3. Adopt advanced finishing technologies: Finishing technologies such as resin finishing and anti-shrinkage finishing can significantly improve the dimensional stability of fabrics. These technologies change the structure and properties of fibers through chemical or physical methods to achieve the purpose of reducing shrinkage rate.

4. Correct washing and maintenance: For consumers, correct washing and maintenance methods are also important means to reduce the shrinkage rate of underwear fabrics. It is recommended to follow the washing instructions on the underwear label to avoid using excessive hot water temperature, strong detergents and excessive mechanical force. At the same time, avoid direct sunlight and excessive wringing when drying to reduce the dimensional changes of the fabric caused by external forces.

5. Reasonable use of fabric softener: Adding an appropriate amount of fabric softener during the washing process can make the fibers of underwear fabric softer and smoother, thereby reducing the friction and entanglement between fibers and helping to reduce the shrinkage rate. However, it should be noted that the amount of fabric softener used should not be too much to avoid adverse effects on the fabric.

IV. Conclusion

The shrinkage rate of underwear fabric is one of the important indicators for measuring its dimensional stability. Understanding and mastering the standards, test methods and reduction strategies of the shrinkage rate of underwear fabric are of great significance for improving product quality and meeting consumer needs. Through measures such as choosing high-quality fabrics, reasonably designing production processes, adopting advanced finishing technologies, correct washing and maintenance, and reasonable use of fabric softeners, we can effectively reduce the shrinkage rate of underwear fabric and provide consumers with better quality and more comfortable underwear products. At the same time, with the continuous progress of technology and the continuous change of consumer needs, the control of the shrinkage rate of underwear fabric will also become more refined and scientific.

• Xiamen Unitex Trade CO.,LTD.
• Website: www.unitexunderwear.com
• E-mail: [email protected]
• Tel: 0086-186 5081 3853