Views: 28 Author: Site Editor Publish Time: 2024-07-22 Origin: Site
The production process of hot air nonwovens: Hot air nonwovens can be realized by different heating methods. The bonding method and process, fiber type and carding process and fiber web structure will ultimately affect the performance and appearance of the nonwoven.
Hot roll bonding can be used, for fiber webs containing low melting point fibers or bicomponent fibers. Hot air bonding can also be used. For ordinary thermoplastic fibers and their blends with non-thermoplastic fibers, hot roll bonding can be used. In the case of the same net formation process, the thermal bonding process has an important impact on the performance of non-woven, and determines the use of the product.
The main factors affecting the performance of diaper topsheet hot air nonwoven fabrics:
The carrier of heat is hot air, hot air bonding process. As the hot air penetrates the fiber network, the heat is transferred to the fibers to melt and produce bonding. Therefore, the hot air temperature, pressure, fiber heating time and cooling rate will directly affect the performance and quality of the product.
The longitudinal and transverse strength of the product are increased with the increase of the hot air temperature. However, the softness of the product decreases, and the feel also becomes hard. Table 1 for the production of 16g / m products, strength, softness with the change in temperature.
Pressure should be increased accordingly, hot air pressure is an important parameter affecting the hot air bonded products. Generally with the increase in the amount and thickness of the fiber network. In order to make the hot air smoothly through the fiber network, but before the fiber network does not produce bonding, the pressure is too high will destroy its original structure, resulting in uneven fiber network.
There must be enough heating time. In production, the heating time of the fiber network depends on the production speed. To ensure that the fiber is fully melted. When changing the production speed, the hot air temperature and air pressure must be increased accordingly to ensure the stability of the product.