Surface treatments of nonwoven materials

Abstract

The purpose of this thesis was to test an aerosol coating technique for nonwoven wet laid filter media. This thesis was done for Ahlstrom Tampere Corporation. Co-operating with Beneq Corporation the trials were set to test the nFOG™- equipment, the aerosol thin film coating equipment.

Ahlstrom Tampere Corporation wants to explore new techniques for chemical bonding and therefore in the theory part of this thesis the main focus is on alternative coating techniques. Special methods such as atomic layer deposition, liquid flame spray method and formation of self-assembled monolayers are introduced. These surface treatment methods are used for applications where uniform coating quality is requirement. From these techniques the liquid flame spray method could be suitable for nonwoven materials since it has been used for coating paper.

The empirical part consists of trials and testing trial materials. The trials were held in Ahlstrom’s premises. The test results were positive. The equipment worked well even with high solid content binders and the coating quality was uniform.

Key words: nonwoven, filter media, chemical bonding, atomic layer deposition, liquid flame spray