This inventor holds 1 USPTO granted patent. Top assignees: Cataler Corporation, Toyota Jidosha Kabushiki Kaisha. Active years: 2026.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile
Company Filing History:
1 out of 261 
1 out of 39,078 
Years Active: 2026
Title: Hiroki Shirakawa: Inventor in Exhaust Gas Purification
Introduction
Hiroki Shirakawa is an inventor based in Toyota, Japan. His work includes an invention for purifying exhaust gas, and the information provided lists 1 patent associated with him.
Latest Patents
His listed patent, “Exhaust Gas Purification Device and Method for Manufacturing Exhaust Gas Purification Device,” describes a substrate with upstream and downstream ends and two catalyst layers extending across different regions. The first layer contains a rhodium-based catalyst and a cerium-containing oxide. Its rhodium particles have a mean particle size of 1.5 to 18 nanometers. The second layer contains another rhodium-based catalyst, while the cerium content in the first layer, measured relative to the substrate volume in its region, is higher than in the second layer. The patent also addresses a method for manufacturing the device.
Career Highlights
Shirakawa is associated with Toyota Jidosha Kabushiki Kaisha and Cataler Corporation. The available information does not specify his roles or the dates of his work with these companies.
Collaborations
Shogo Shirakawa is identified as his coworker. Further details about their collaboration are not provided.
Conclusion
Hiroki Shirakawa’s listed patent focuses on a layered catalyst design that uses rhodium and varying cerium content to support exhaust gas purification.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile