Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
230 words
An improved method of making a flexible printing plate adapted to be mounted on a magnetic cylinder of a printing press, comprising the steps of mixing a ferrous metal powder within a liquid vinyl material to form a mixture, forming a face layer of at least partially cured vinyl material substantially free of the ferrous metal powder, casting the mixture onto the face layer of at least partially cured vinyl material to form a base layer of gnerally uniform thickness, heating the base layer with the face layer to fuse the layers into a multi-layer mold sheet of substantially uniform thickness, placing the face layer of the mold sheet into contact with a porous printing plate mold having a substantially uniform thickness and a recessed impression, heating the assembly of the mold sheet and the printing plate mold, placing the heated assembly into a press having a fluid actuated diaphragm, pressurizing the diaphragm with uniform fluid pressure for pressing the face layer of the mold sheet into the recessed impression to form a printing plate having a rasied printing surface corresponding to the impression, allowing the assembly to cool while the mold sheet is being pressed against the printing plate mold, reforming the base layer including the ferrous metal powder to provide the printing plate with a precisely uniform caliper, and stripping the printing plate from the printing plate mold.
Claim 2
Dependent Claim
230 words
An improved method of making a flexible printing plate adapted to be mounted on a magnetic cylinder of a printing press, comprising the steps of mixing a ferrous metal powder within a liquid vinyl material to form a mixture, forming a face layer of at least partially cured vinyl material substantially free of the ferrous metal powder, casting the mixture onto the face layer of at least partially cured vinyl material to form a base layer of gnerally uniform thickness, heating the base layer with the face layer to fuse the layers into a multi-layer mold sheet of substantially uniform thickness, placing the face layer of the mold sheet into contact with a porous printing plate mold having a substantially uniform thickness and a recessed impression, heating the assembly of the mold sheet and the printing plate mold, placing the heated assembly into a press having a fluid actuated diaphragm, pressurizing the diaphragm with uniform fluid pressure for pressing the face layer of the mold sheet into the recessed impression to form a printing plate having a rasied printing surface corresponding to the impression, allowing the assembly to cool while the mold sheet is being pressed against the printing plate mold, reforming the base layer including the ferrous metal powder to provide the printing plate with a precisely uniform caliper, and stripping the printing plate from the printing plate mold.
Claim 3
Dependent Claim
35 words
A method as defined in claim 1 including the step of preheating the porous printing plate mold to remove substantially all moisture from the mold before the face layer is pressed into the recessed impression.
Claim 4
Dependent Claim
72 words
A method as defined in claim 1 including the step of overlaying the base layer of the heated assembly of the mold sheet and the printing plate mold with a flexible porous cloth-like material prior to pressing the face layer of the mold sheet into the recessed impression of the printing plate mold, and removing the porous cloth-like material after the face layer of the mold sheet is pressed into the mold.
Claim 5
Dependent Claim
50 words
A method as defined in claim 1 wherein the base layer of the printing plate is reformed by shaving the base layer and the ferrous metal poweder while the printing plate mold remains attached to remove a portion of the base layer including a corresponding portion of the metal powder.