This invention relates to forming very small mold cavities for molding small features integral with a base sheet, and has particular application to the production of touch fasteners and the like.
Fastener elements for hook-and-loop touch fasteners may be made as disclosed in Fischer U.S. Pat. No. 4,794,028. In commercial production, a mold roll is formed from a large number of thin, disk-shaped mold plates and spacer plates which are stacked concentrically on a central barrel. At the periphery of the mold plates are cavities for molding the hook elements. Typically, each mold cavity of the plate is formed by wire electro-discharge machining (EDM) methods. Also, the required small wire diameter limits the rate at which the mold plates can be produced.