摘要 |
Relatively thin (e.g., thickness of less than about 2.5 mm, and typically no greater than about 1.0 mm) plates for synthetic fiber-forming spin packs include a first metal layer exhibiting a relatively slow photochemical etching property and a second metal layer exhibiting a relatively fast photochemical etching property which are adhered (laminated) to one another to form a composite substrate structure. The differential etch rates as between the first and second metal layers permit relatively dimensionally larger distribution channels and relatively dimensionally precise through holes to be formed in the composite substrate. In this regard, the second metal layer permits the formation via photochemical etching of dimensionally deeper and/or wider polymer distribution channels. The first metal layer, on the other hand, allows for the formation of relatively dimensionally precise through holes via concurrent (simultaneous) etching with the second metal layer.
|