James H Rea

Title: Innovations of James H. Rea

Introduction

James H. Rea is a notable inventor based in Corpus Christi, TX (US). He has made significant contributions to the field of polymer chemistry, particularly in the development of low optical polymers and copolymers for photoresists. With a total of 9 patents to his name, Rea's work has had a substantial impact on various imaging systems.

Latest Patents

One of Rea's latest patents is titled "Process for making low optical polymers and copolymers for photoresists." This invention pertains to polymers that comprise poly(4-hydroxystyrene) or substituted poly(4-hydroxystyrene). These polymers exhibit low optical density over a wavelength range from about 240 to about 260 nm, as well as low optical density over the near UV and visible spectrum (310 to 800 nm). The production process involves polymerizing 4-acetoxystyrene and/or substituted 4-acetoxystyrene monomers, with or without other comonomers, followed by transesterification. The preferred embodiment utilizes at least one alcohol as a reaction medium, a chain transfer agent, and a transesterification reactant, resulting in an unusually economic process. These polymers are particularly useful as photoresist components for deep UV, X-ray, and E-Beam imaging systems.

Another significant patent is "Process for the preparation of salts of 4-hydroxystyrene." In this process, 4-acetoxystyrene is reacted with a base in a solvent to form a salt of 4-hydroxystyrene via saponification. Alternatively, 4-hydroxystyrene can be reacted with a base to form a salt directly. In this case, the 4-hydroxystyrene is prepared by the transesterification of 4-acetoxystyrene. The salt of 4-hydroxystyrene is then reacted, preferably in situ, with di-tertiary-butyl-dicarbonate to form 4-tertiarybutoxycarbonyloxystyrene.

Career Highlights

James H. Rea is currently associated with Hoechst Celanese Corporation, where he continues to innovate in the field of polymer chemistry. His work has been instrumental in advancing technologies related to photoresists and imaging systems.

Collaborations