Introduction Of Hot Air Through Non Woven

1.Hot air through non woven

Hot air through non woven is a kind of hot air bonded (hot rolling, hot air) non-woven fabric. Hot air through non woven is a kind of non-woven fabric. After the fibers are combed, the hot air on the drying equipment can be used to penetrate the fiber web for bonding.Hot air bonding refers to the bonding production method that uses hot air to penetrate the fiber web on the drying equipment, heat and melt it. Hot air through non woven adopts different heating methods, and the performance and style of the products are also different. Generally, hot air bonded products have the characteristics of fluffy, soft, good elasticity and strong warmth retention, but have low strength and are easy to deform. In hot air bonding production, before the fiber web enters the drying chamber, a certain proportion of low-melting point bonding fibers are mixed into the fiber web, or bi-component fibers are used, or a certain amount of bonding powder is applied using a powder spreading device. The melting point of the powder is lower than that of the fibers. Melts rapidly when heated, causing interfiber adhesion. The heating temperature of hot air bonding is generally lower than the melting point of the main fiber. Therefore, when selecting fibers, the matching of the thermal properties of the main fiber and the bonding fiber should be considered, and the difference between the melting point of the bonding fiber and the melting point of the main fiber should be as large as possible to reduce the thermal shrinkage of the main fiber and maintain the original properties of the fiber. Binder fibers have lower strength than normal fibers. Therefore, the amount of bonding fiber should not be too large, generally controlled at 15% to 50%. Due to its small thermal shrinkage, bicomponent fibers are very suitable for use alone or as binder fibers for the production of air-bonded nonwovens, forming a point-bonded structure with good results. The product produced by this method has high strength and soft touch.

2.Hot air through non woven fiber

Hot air through non woven fiber web composed of thermoplastic synthetic fibers can be reinforced by heat bonding, such as polyester, nylon, polypropylene, etc. Air-through non-woven fabrics Since cotton, wool, hemp, viscose and other fibers are not thermoplastic, a fiber web composed only of these fibers cannot be reinforced by thermal bonding. However, a small amount of cotton, wool and other fibers can be added to the thermoplastic web to improve certain properties of the nonwoven, but generally no more than 50%. For example, cotton/polyester calender bonded nonwovens with a blend ratio of 30/70 can significantly improve hygroscopicity, hand, and softness. It is very suitable for medical hygiene products. The strength of hot air through non woven decreases with increasing cotton fiber content. Of course, for fiber webs composed entirely of non-thermoplastic fibers, powder spreading thermal bonding can also be considered for reinforcement.

3. The hot rolling bonding method

The hot rolling bonding method is generally suitable for fiber webs with a weight in the range of 20-200g/m², and suitable for thin products with a net fiber weight of 20-80g/m². If the fiber web is too thick, the bonding effect of the middle layer is poor, and it is easy to Stratification occurs.

Hot air bonding is suitable for quantitative products of 16~2500g/m². In recent years, thin air-bonded nonwovens have developed rapidly, and their quantitative values are generally 16~100g/m². In addition, thermal bonding is also commonly used to produce composite nonwovens (such as fusion-laminated nonwovens) or as a supplement to other reinforcement methods. For example, the strength and dimensional stability of acupuncture products can be significantly improved by incorporating a small amount of low-melting fiber into the fiber web, acupuncture reinforcement, and hot-air bonding.