Ultrathin film, process for production thereof, and use thereof for concentrating a specific gas from a gas mixture

Abstract

An ultrathin film composed substantially of a silicon-containing polymer comprising bonded units derived from (A) at least one polyamine selected from the group consisting of silicon-containing polyamines containing in the molecule at least two primary and/or secondary amino groups not directly bonded to the silicon atom, (B) at least one compound selected from the group consisting of polysiloxane-type compounds having at least two acidic hydroxyl groups in the molecule, and (C) at least one polyisocyanate selected from the group consisting of polyisocyanates having at least two isocyanate groups in the molecule. The ultrathin film on the supporting microporous substrate is useful for production of a gaseous mixture containing a specific gas such as O.sub.2 in a higher concentration from a gaseous mixture of at least two gases such as air.

Dependencies are inferred from the claim text.