The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 2002
Filed:
Sep. 12, 2000
Toray Industries, Inc., Tokyo, JP;
Abstract
The present invention relates to a composite semipermeable membrane which is characterized in that it is a composite semipermeable membrane in which there is formed by polycondensation on top of a microporous support membrane a crosslinked polyamide ultra-thin membrane layer from polyfunctional amine, polyfunctional acid halide and polyfunctional acid anhydride halide, and the flow of water permeate at an operating pressure of 0.3 MPa, a temperature of 25° C. and a pH of 6.5 lies in the range from 0.8 to 4.0 m /m .day and, furthermore, the percentage humic acid removal is at least 98%; a method for the production thereof; and a water purification method employing same. With the composite semipermeable membrane obtained by means of the present invention it is possible, in particular, to recover drinking water at a high rate by permitting passage of silica and preventing deposition thereof at the membrane surface while selectively separating/removing the pollutants and trace quantities of harmful materials and their precursors, etc, contained in the raw water in water treatment plants.