Melt blown nanofiber technology


In order to spin nanofibers, the spinneret hole is much thinner than that on ordinary PLA melt blown equipment. When NTI is as small as 0.0635 mm (i.e. 63.5 microns) or 0.0025 inches, the spinneret plate with module structure can be combined into a total width of more than 3 meters. The diameter of melt blown fiber spun in this way is about 500 nm. The diameter of the thinnest single fiber can reach 200 nm.

The PLA melt blown equipment for spinning nanofibers has small spray holes, so if no measures are taken, the output will be greatly reduced. Therefore, NTI adopts to increase the number of spray holes, and each spray plate has 3 or more rows of spray holes. When many unit components (depending on the width) are combined together, the output can be greatly improved during spinning. The actual situation is that when 63.5 micron holes are used, the number of holes per meter of spinneret in a single row is 2880. If three rows are used, the number of holes per meter of spinneret can reach 8640, so its output can be equivalent to that of spinning ordinary melt blown fiber.

Because the thin spinneret with high-density holes of the PLA melt blown is expensive and easy to crack (it will crack when heated under high pressure), all companies have developed new bonding technology to enhance the fastness of spinneret so that it will not leak under high pressure.

Nano melt blown fiber can be used as filter medium, which can significantly improve the filtration efficiency. Some data also show that: due to the finer fiber in the nano melt blown nonwovens, the melt blown fabrics with lighter weight and spunbonded composite can still bear the pressure of the same water head, and the SMS products made of them can reduce the proportion of melt blown fiber.