Platemaking apparatus

In combination with photopolymer platemaking apparatus wherein a horizontal flat plate, a photo transparency on said flat plate, a cover film on said photo transparency, and a movable carriage to traverse said flat plate, said carriage having photopolymer supply means, a press roll and backing sheet supply means all mounted on said carriage, are provided for making a photorelief printing plate, wherein the improvement comprises:

• a substantially vertical plate connected to said carriage, said vertical plate acting as a back wall and as a doctor blade;
• scoop means abutting said vertical plate and being movable with respect to said vertical plate, movement of said scoop means with respect to said vertical plate defining a bottom opening between said scoop means and said vertical plate to control the flow of photopolymer therethrough;
• actuator means interconnecting said scoop means and said vertical plate to control the speed and amount of movement of said scoop means with respect to the vertical plate and the resulting opening between said scoop means and said vertical plate, whereby said opening provides uniform flow of a photopolymer onto the surface of the cover film and said vertical plate doctors said photopolymer to uniform thickness before the application of a backing sheet onto the surface thereof;
• a shim means connected to said flat plate, said press roll riding on said shim, the height of said press roll from said flat plate being determined by the thickness of said shim means;
• and
• gear means connected to said press roll and said flat plate, said gear means pivotally mounted to said carriage and being thereby vertically adjustable to compensate for the height of said press roll from said flat plate, said gear means driving said carriage.