Core Viewpoint - Huafeng Chemical Co., Ltd. has applied for a patent for a preparation method of sulfonic acid modified polyurethane fibers, indicating a focus on innovation in material science and potential market expansion in the textile industry [1] Group 1: Patent Application Details - The patent application is titled "A Preparation Method of Sulfonic Acid Modified Polyurethane Fibers" with publication number CN121295377A and was filed on November 2025 [1] - The preparation method involves a three-step process: prepolymerization and chain extension reaction, ring-opening reaction with sulfonic acid lactone compounds, and final spinning process to produce the fibers [1] Group 2: Technical Advantages - The method introduces sulfonic acid groups after the chain extension reaction, which helps avoid adverse effects on polymer stability that could arise from improper timing of sulfonic acid introduction [1] - The resulting sulfonic acid modified polyurethane fibers exhibit excellent mechanical properties along with good dyeing performance and color fastness [1]