Method for graining metal lithographic plate
OwnerJoseph F. Bednarzinventor
Life of this patent
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Abstract
Aluminum lithographic plate stock is grained in a continuous process wherein the strip to be grained and a cloth fabric material are brought into rubbing contact in the presence of an aqueous chloride salt graining solution while an electrical potential is applied such that the strip is the anode. The product produced by the graining process has a unique porous grained finish.
Claims17
A method useful for graining aluminum strip for use as lithographic plate comprising the steps of bringing the strip and a cloth fabric into rubbing contact over a metal backing member while applying an aqueous chloride salt solution to the surface of the strip;
- moving the strip and the fabric relative to each other while in contact to remove reaction products from the strip surface and expose fresh surface area to the solution;
- and, establishing an electrical potential between the backing member as the cathode and the strip as the anode.
A method for graining aluminum strip for use as lithographic plate comprising the steps of:
- (a) applying a graining solution comprising an aqueous solution of a chloride salt to a cloth fabric;
- (b) bringing the strip and the fabric into contact over a rigid electrically conducting backing surface;
- (c) moving the strip and the fabric relative to each other while in contact to at least partially remove reaction products from the strip;
- (d) applying a direct electrical potential between the backing surface as the cathode and the strip as the anode.
A method of producing an anodized grained lithographic plate from an aluminum lithographic plate stock strip comprising the steps of:
- (a) producing a grained strip by moving the strip and a cloth fabric relative to each other while in frictional contact in the presence of an aqueous chloride salt solution;
- and, applying an electrical potential having a DC component such that the strip is the anode;
- and thereafter,
- (b) anodizing the grained strip by moving the grained strip and a cloth fabric relative to each other while in frictional contact in the presence of an anodizing solution;
- and, applying an electrical potential having a DC component such that the grained strip is the anode.
Dependencies are inferred from the claim text.