Airbag filter assembly and method of assembly thereof

A method of forming an airbag inflation filter assembly comprising the steps of:

• providing a substantially rigid support tube having perforations therethrough, the support tube defining an axis;
• helically winding over the perforations on the support tube a first layer of convolutions of a continuous inorganic strand having a core from which filaments or fiber segments project outwardly, successive convolutions being oppositely wound in each layer to provide interwoven cores, with cores of adjacent convolutions being substantially uniformly spaced to define four-sided openings within which projecting filaments or fiber segments intermesh to form particulate traps;
• and
• helically winding over the first layer a second layer of the continuous inorganic strand, the cores of which define similar openings bridged by similar traps, each convolution of strand in at least one of the first layer and the second layer being wound at from about 75 degrees to about 85 degrees to the axis of the support tube.