Vacuum printing frame.

摘要

A vacuum printing frame (100) includes a backing plate (126); a pressurizable bladder assembly (120) positioned on the backing plate, the bladder assembly including a lower wall (130) positioned on the backing plate (126), a plurality of partitions sealed around lower edges thereof to the lower wall and defining a series of interconnected, nested chambers (140, 147, 146) arranged in alignment from and pressurizable from a head end to a foot end of the vacuum printing frame, and a plurality of holes (172) in each partition at positions close to the securement of the respective partition to the lower wall to provide fluid communication between adjacent bladder chambers; a flexible, fluid impervious membrane (118) positioned above the bladder assembly for supporting a mask and photosensitive sheet (116); a transparent plate (114) movable between an open position for permitting the mask and photosensitive sheet to be positioned on the membrane, and a closed position for sandwiching the mask and photosensitive sheet between the membrane and the transparent plate in an evacuation region defined between the membrane and the transparent plate; a blower (180) for supplying air under pressure to the bladder assembly when the transparent plate is in the closed position to apply a force pressing the photosensitive sheet and mask against the transparent plate in a predetermined spatial pattern, starting from an innermost chamber (140) at the head end to an outmost chamber (148); and an evacuation port (124) fluidly connected with the evacuation region for evacuating the same, the evacuation port positioned at the head end of the vacuum frame.