COFORM FILTER MEDIA HAVING INCREASED PARTICLE LOADING CAPACITY

摘要

Disclosed is a filter medium having at least a first layer containing a stabilized matrix of thermoplastic filaments and at least one secondary material; and a second layer having a stabilized matrix of thermoplastic filaments and optionally of at least one secondary material. Each of the layer of the filter medium has a different compositional ratio of the components to result in a gradient structure. The compositional gradient for the layers of the coform results in a filter having improved capacity, which extends the life of the filter medium, as compared to a filter without the compositional gradient. The present invention also provides a method of removing particles from a fluid containing particles. The method of the present invention includes contacting the fluid containing particles with the filter medium of having the two layers described above in a manner such that the fluid containing particles is passed through the first layer of the filter medium before the second layer.