Apparatus for applying a conversion liquid to electrostatic copy material

Claim 1

Apparatus for subjecting a length of copy material to the action of a conversion liquid in a conversion zone through which said length passes along a path with its image side facing downwardly, said apparatus comprising: a. trough means extending transversely of said path and adapted to contain a supply of conversion liquid to a predetermined level therein; b. a first roller mounted over said trough means for rotation about a horizontal axis extending transversely of said path and at an elevation such that a portion of said roller will be immersed in the conversion liquid in said trough means; c. a second roller mounted above said first roller for rotation about an axis parallel with said first mentioned axis, the adjacent peripheral surfaces of said first and second rollers being in predetermined, close, spaced relationship to define a metering gap for receiving the length of copy material therethrough; d. means for advancing the length of copy material through said gap at a predetermined speed; e. upper and lower squeegee rollers mounted for rotation about respective axes parallel with the aforementioned axes and having their peripheral surfaces in rolling engagement with each other to define a nip for receiving the copy material after it has passed through said gap, said lower squeegee roller being at an elevation over said trough means such that a portion thereof will be immersed in the conversion liquid in said trough means; f. drive means connected with at least one of said squeegee rollers for rotating the latter such that their linear peripheral speed is substantially the same as said predetermined speed whereupon such rollers apply a squeegee action to the copy material and advance the same through said conversion zone; and g. other drive means connected with said first roller for rotating the same in the same direction as said lower squeegee roller and such that the linear peripheral speed of said first roller is a multiple of said predetermined speed by a factor of at least two but less than four whereupon said first roller develops a film of conversion liquid on a portion of its peripheral surface and applies such film as a metered layer to the underside of the copy material as the same passes through said gap.