David L Allen

Title: David L. Allen: Innovator in Photographic Chemistry

Introduction

David L. Allen is a notable inventor based in Holcomb, NY (US). He has made significant contributions to the field of photographic chemistry, particularly through his innovative patent related to triazolothiadiazines.

Latest Patents

David L. Allen holds a patent for the "Desulfurization of triazolothiadiazines - Pyrazolotriazoles." This invention focuses on the utility of 3,6-disubstituted-1H-pyrazolo[5,1-c]-1,2,4-triazoles, which are valuable in the photographic arts, specifically as magenta couplers. The patent outlines a two-step process for synthesizing these compounds, beginning with a ring contraction and diacylation, followed by hydrolysis of the acyl groups and desulfurization. The second step is conducted using an aqueous mixture of hydrohalic acid, such as hydrochloric acid, and hypophosphorous acid, which minimizes the formation of sulfur and sulfur-containing impurities.

Career Highlights

David L. Allen is associated with Eastman Kodak Company, where he has applied his expertise in photographic chemistry. His work has contributed to advancements in the field, enhancing the quality and efficiency of photographic materials.

Collaborations

Throughout his career, David has collaborated with notable colleagues, including Chang K. Kim and Wayne N. Lamicela. These partnerships have fostered innovation and development in their shared field of expertise.

Conclusion

David L. Allen's contributions to photographic chemistry through his patent demonstrate his innovative spirit and dedication to advancing the industry. His work continues to influence the field, showcasing the importance of research and collaboration in driving technological progress.