Patent ID: 7686018
Filing Date: 2010-03-30
Classification: A41D,A62B

Abstract:
1. A mask for the protection against biological agents, comprising: a cup-shaped chamber defined by a central panel, an upper panel, and a lower panel joined together; each of the central panel, the upper panel, and the lower panel comprised of a plurality of layers, at least one of the layers composed of a cellulose-based substrate supporting a fiber-based matrix structure of borosilicate micro-glass fibers bound together by a vinyl acetate resin, and iii) a silicone based coating imparting hydrophobic properties on the structure and the substrate; a boundary sealing layer located on perimeter edges of the cup-chamber; and a cylinder-shaped valve located on the outside of the central panel configured to facilitate passage of exhaled air from an interior of the mask to ambient air, the valve comprising a valve seat secured by a raised valve cover, the valve cover including apertures, an upper end of the valve seat including a relief with a concave surface and defining a circumference of the relief, a continuous, cylindrical cross-sectional shaped, O-ring located along an entirety of the concave surface of circumference of the relief, a circular valve flap with outside edges located on a upper side of the O-ring, the valve cover extending over and covering the valve flap, the relief, and the O-ring, the valve cover further including a flap support pressing down on a center of the valve flap.