Material Difference of Dryer Fabric

1 Main materials

The most commonly used dryer fabric material is polyester, which is also divided into round filament polyester and flat filament polyester according to the differences in dryer fabric weaving and manufacturing.

According to daily experience in using dryer fabric, flat filaments have a better use effect than round filaments. On the one hand, a flat filaments structure can provide a better paper contact surface, thereby reducing the probability of dryer fabric marks occurring. On the other hand, due to geometric differences, flat filaments are superior to round filaments in controlling the accumulation of dirt and dirt in adhesive materials.

Early dryer fabric used round warp filaments and round weft filaments; Standard dryer fabric usually use flat warp filaments and round weft filaments; There are also some dryer fabric that use all flat filaments designs.

2 Anti pollution

In addition to avoiding dryer fabric pollution through the geometric design of the filaments, the adhesion of adhesive substances also requires reducing their surface energy by adding fluorine substances to the polyester material, which makes it difficult for pollutants to adhere to the surface. Therefore, it greatly reduces the occurrence of paper diseases such as adhesive black particles caused by the accumulation of dirt and dirt in the dryer fabric, decreased air permeability, insufficient drying capacity, uneven moisture content in the paper machine's banner, and black spots.

3 Anti hydrolysis

Due to the fact that the operating environment of the dryer grid is mainly inside the closed hood, the environment is in a severe high-temperature and high-humidity environment. In addition, some base paper has a non neutral PH value, so it is highly corrosive to polyester materials. The end of the service life of most dryer fabric is not due to dryer net wear (unlike forming fabric and woolen fabrics, almost all of which are caused by rolling friction), but rather due to dryer net hydrolysis caused by dirt or corrosion. To reduce the risk of hydrolysis, it is common to add anti hydrolysis agents to dryer fabric threads to reduce this trend.

PS: It should be noted that hydrolysis resistant agents are prone to volatilization and precipitation under conditions of 160 ℃ and above. Due to their toxicity, additional attention should be paid when producing food type paper and paperboard (usually, the temperature of the hood and dryer cylinder is also difficult to reach this temperature level)

4 PPS edge

Everyone should be familiar with the special color of the edges of the dryer fabric. This is the PPS reinforced edge design. Due to the use of a special material such as polyphenylene sulfide, the edges of the dryer fabric are endowed with strong acid and alkali corrosion resistance and hydrolysis resistance. However, due to the high price, soft material, poor wear resistance, and other issues, this material is only used at the edge of the dryer fabric. In addition, in order to reduce costs, it is often used for the upper dryer fabric (higher temperature and humidity) to use this design containing PPS waterproof edge stripping, while the lower one is not required to reduce costs.