Photographs created with silver-halide film soon may be as much a memory as the moments they captured. Researchers at Polaroid Corp. in Waltham, Mass., have developed film that can capture higher resolution images than traditional film and that can be developed without a "wet" process.

The new film contains three layers of iodonium salts sensitized by cationic dyes that can be converted by photolysis to superacids. During development, the film is heated, causing the superacids to catalyze the formation of large amounts of weaker acid from a molecule called an acid amplifier. Indicator dyes then diffuse into regions where this acid has been produced, forming a picture.

The researchers report in the Aug. 8 issue of Sciencexpress that the film is still too insensitive to be used in conventional cameras but may be ideal for digital-printing methods that expose it to laser or LED sources.