Location History:
- Yokohama, JA (1976)
- Yokohama, JP (1979 - 1993)
Company Filing History:
10 out of 161 
8 out of 1,357 
3 out of 23 
Years Active: 1976-1993
Title: Iwao Ohshima: Innovator in Silica Processing
Introduction
Iwao Ohshima is a prominent inventor based in Yokohama, Japan, known for his significant contributions to the field of silica processing. With a total of 14 patents to his name, he has developed innovative methods that enhance the quality and application of silica in various industries.
Latest Patents
One of Ohshima's latest patents is a process for preparing silica having a low silanol content. This process involves heating amorphous silica in an atmosphere of low partial pressure of water vapor, maintaining the silica at temperatures ranging from 600°C to 1000°C during the first heating step, and then at 1200°C or more during the second heating step. The resulting silica is particularly advantageous as a raw material for quartz glass, especially for producing crucibles used in the growth of silicon single crystals.
Another notable patent is a method for producing unsintered cristobalite particles. This method entails heating amorphous silica particles at temperatures between 1400°C and 1700°C in the presence of cristobalite particles. The process allows for the conversion of amorphous silica into cristobalite while maintaining the particle form. The dense cristobalite produced is low in alkali content and is utilized as a filler, dispersing agent, and material for high-quality artificial quartz and transparent quartz glass.
Career Highlights
Throughout his career, Iwao Ohshima has worked with notable companies such as Nitto Chemical Industry Co., Ltd. and Mitsubishi Rayon Company, Limited. His work has significantly impacted the silica industry, leading to advancements in materials used in various applications.
Collaborations
Ohshima has collaborated with esteemed colleagues, including Koichi Orii and Naotake Watanabe, contributing to the development of innovative silica processing techniques.
Conclusion
Iwao Ohshima's contributions to silica processing through his patents and collaborations have established him as a key figure in the field. His innovative methods continue to influence the production and application of silica in various industries.