Company Filing History:
Years Active: 1994-1997
Title: Takaaki Kuwana: Innovator in Polycarbonate Production
Introduction
Takaaki Kuwana is a prominent inventor based in Hyogo, Japan. He has made significant contributions to the field of polycarbonate production, holding a total of 10 patents. His innovative approaches have enhanced the efficiency and quality of polycarbonate manufacturing processes.
Latest Patents
Kuwana's latest patents focus on advanced methods for producing polycarbonate. One notable patent describes a process for producing polycarbonate by subjecting a dihydroxy compound and a diester of carbonic acid to melt polycondensation through transesterification. This method allows for the preparation of a polycarbonate prepolymer in the first-stage reaction, followed by polycondensation in the second-stage reaction. The process is designed to operate within a residence time of 15 to less than 60 minutes, utilizing at least one paddle-type self-cleaning twin-screw extruder. This innovative approach enables the production of a colorless, transparent polycarbonate with a high molecular weight at an industrial scale.
Another patent outlines a method for producing polycarbonate through transesterification from a dihydroxy compound, such as 2,2-bis(4-hydroxyphenyl)propane, and a diester of carbonic acid, like bisphenyl carbonate. This process is conducted in a reactor made of stainless steel, which is treated by electropolishing or acid pickling. The use of specific nitrogen-containing, electron-donating compounds as transesterification catalysts further enhances the efficiency of the process.
Career Highlights
Kuwana is currently associated with Daicel Chemical Industries, Ltd., where he continues to innovate in the field of polymer chemistry. His work has significantly impacted the production methods of polycarbonate, making them more efficient and environmentally friendly.
Collaborations
Throughout his career, Kuwana has collaborated with notable colleagues, including Yasuhiro Oshino and Yutaka Fukuda. These partnerships have fostered a collaborative environment that encourages innovation and the sharing of ideas.
Conclusion
Takaaki Kuwana's contributions to polycarbonate production exemplify the importance of innovation in the field of chemistry. His patents reflect a commitment to advancing manufacturing processes, ensuring high-quality products for industrial applications.