Patent ID: 7288223

Claim:
A method for producing a filter for a respirator or fan unit, said method comprising the steps of: intermixing a granular adsorbent, absorbent, chemisorptive, or catalytic material, or activated carbon with a meltable polymer(s) to produce a mixture; molding the mixture in a connecting part comprising an inner surface with a complete or partial a) groove into which the mixture is formed or b) a tongue with a substantial length against which the mixture is formed; and heating the mixture under pressure so as to make a molded piece that is adapted to work as a filter element for a respirator or fan unit and a substantially gastight connection between the molded piece and the inner surface of the connecting part at an interface so that the molded piece is formed so that it respectively engages in or at least partially encloses the groove or tongue and so that the molded piece and connecting part are stably connected to form a unit that can be operatively connected to a respirator or fan unit, the molded piece and connecting part constructed so that: i) in the event the inner surface has a groove, gas flowing in a straight line path through the interface is required to pass through the mixture at the groove; and b) in the event the inner surface has a tongue, gas flowing in a straight line path through the interface is intercepted by the tongue and diverted out of the straight line path and thereby required to pass through the mixture.