Graphic material registration apparatus and method

Abstract From the Canadian patent

Improved method and apparatus for supporting photographic sheet materials in intimate surface contact during contact exposure includes a flexible membrane which forms a common boundary wall between two gas-tight chambers. Air at ambient pressure is admitted to one chamber at a controlled rate slower than air is evacuated from the other chamber containing the photographic sheet materials. Progressive expansion of the surface area of contacting force assures that residual volumes of air between photographic sheets are squeezed out in an orderly pattern and not trapped in isolated pockets that distort resulting photographic images.