Presidential Green Chemistry Challenge: 1997 Greener Reaction Conditions Award
Imation (technology acquired by Eastman Kodak Company)
Innovation and Benefits: Imation's DryViewTM Imaging Systems use a new type of photographic film for medical imaging that uses heat instead of hazardous developer chemicals. During 1996, Imation delivered more than 1,500 DryViewTM Imaging Systems worldwide. These units alone eliminate the annual disposal of over half a million gallons of developer chemicals and 54.5 million gallons of contaminated water and reduce workers' exposure to chemicals.
Summary of Technology: Photothermography is an imaging technology whereby a latent image, created by exposing a sensitized emulsion to appropriate light energy, is processed by the application of thermal energy. Photothermographic films are easily imaged by laser diode imaging systems, with the resultant exposed film processed by passing it over a heat roll. A heat roll operating at 250 °F in contact with the film will produce diagnostic-quality images in approximately 15 seconds. Based on photothermography technology, Imation's DryViewTM Imaging Systems use no wet chemistry, create no effluent, and require no additional postprocess steps such as drying.
In contrast, silver halide photographic films are processed by being bathed in a chemical developer, soaked in a fix solution, washed with clean water, and finally dried. The developer and fix solutions contain toxic chemicals such as hydroquinone, silver, and acetic acid. In the wash cycle, these chemicals, along with silver compounds, are flushed from the film and become part of the waste stream. The resulting effluent amounts to billions of gallons of liquid waste each year.
Significant developments in photothermographic image quality have been achieved that allow it to compete successfully with silver halide technology. During 1996, Imation placed more than 1,500 DryViewTM medical laser imagers, which represent 6 percent of the world's installed base. These units alone have eliminated the annual disposal of 192,000 gallons of developer, 330,000 gallons of fixer, and 54.5 million gallons of contaminated water into the waste stream. As future systems are placed, the reductions will be even more dramatic.
DryViewTM technology is applicable to all industries that process panchromatic film products. The largest of these industries are medical radiography, printing, industrial radiography, and military reconnaissance. DryViewTM is valued by these industries because it supports pollution prevention through source reduction.