Monday, February 13, 2017

Polychrome makes positive diazo

Polychrome makes positive diazo         By Mr. Bob Gumbinner

In conjunction with Fuji Film, we made a resin for positive presensitized plates. Delos Bown started producing this coating which was an ester of diazo oxide with a resin we made from acetone and pyrogallol. Because this ester had extra hydroxyl groups, it held moisture better than the competitive plates which more difficult to develop, especially if the positive transparency was used several times. When Dr. Bown developed an allergy to the diazo, the manufacturing of the positive sensitizer was moved to the building at Cellomer in Newark where the negative diazo was being manufactured. In the 1970s, we hired Al Deutsch, who had worked for GAF. He developed an ester of  the diazo oxide with a six carbon alcohol which made an improved resist for integrated circuit chips. I went to his wedding in New Jersey.

KS note;  

Please see other posts on Dr. Bown

Farewell Dr. Delos Bown       HERE
Dr. Bown Episode                  HERE
Dr. Delos Bown                       HERE