Patent ID: 7201853

Claim:
A method for making a forming structure, the method comprising: a. providing a metal base sheet; b. providing an uncured photoresist polymer; c. providing a mask sheet having light transparent regions; d. providing a light curing means; e. providing an acid; f. providing a caustic; g. applying a continuous layer of uncured photoresist polymer to one surface of the metal base sheet; h. disposing the mask sheet between the continuous layer of uncured photoresist polymer and the light curing means; i. exposing the photoresist polymer through the mask means to cure the portions of the photoresist polymer in register with the transparent regions; j. removing the mask sheet; k. exposing the base sheet to acid for a sufficient time to define at least one protrusion having an upper surface and a side wall defining a first height on the base sheet; l. washing away the acid with the caustic; m. applying photoresist polymer to the upper surface and a side wall of the at least one protrusion; n. exposing the base sheet to acid for a sufficient time to form additional side wall of the at least one protrusion such that the side wall defines a second height, the second height being greater than the first height; and o. washing away the acid with caustic.