TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The material further comprises chopped strands and thermal binding synthetic fibers. The material comprises (parts by weight): glass microfibers (10-99.9, preferably 65-80); the binder (0.1-50, preferably 5-10); the chopped strands (0-70, preferably 0-5); and the thermal binding synthetic fibers (0-90, 15-20). The material has a basic weight of greater than or equal to 10 g/m2, preferably 30-60 g/m2. The material has a porosity of greater than or equal to 85%, preferably greater than or equal to 90%, determined according to standard BCIIV 34-1. The material is obtained by a wet process. Preferred Components: The material has a Cobb60 degree of greater than or equal to three times its weight, determined according to ISO 535. The glass microfibers have a diameter of less than 5 mu m. The chopped strands have a diameter of greater than or equal to 5 mu m and a length of greater than or equal to 3 mm. The synthetic fiber is biocomposite fibers having a polyester core and an (co)polyester external layer having a melting point of less than or equal to 130 degrees C, preferably the diameter of greater than or equal to 5 mu m and a length of greater than or equal to 3 mm.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The binder is crosslinked, preferably thermo crosslinked. The binder is polymer binders based on acrylic acid (preferred), epoxy, phenolic, polyester, and polyurethane. EXAMPLE - Acid electrolytes resistant glass microfiber having an average diameter of 0.8 mu m, was added in a suspension in an aqueous medium. Then a fibrous sheet was formed by draining the suspension. An acrylic polymer binder in the form of an aqueous emulsion (latex) was applied on one side of the sheet to obtain a material. The resulting material was then dried at 150 degrees C for 15 minutes, to remove water to obtain a material comprising 95 parts by weight of the glass microfibers and 5 parts by weight of the binder.