text: The present invention relates to thin film compounds or coating layers which are opaque to ultraviolet light radiation, methods of etching such coating layers or compounds to produce masking patterns, resultant graphic artworks created thereby, and patterned products produced using such graphic artworks.
  Heretofore, thin film coatings for producing graphic artworks such as masks for printed circuits or photo tools for graphic printing have suffered from a variety of known disadvantages. For example, germanium is a well known compound which is opaque to ultraviolet light and hence useful for producing patterned graphic artworks, but has an inherent disadvantage due to its high cost. Metals such as zinc or aluminum could be used for the production of graphic artworks since they are also opaque to ultraviolet light, but an accompanying disadvantage is that rather strong caustic solutions are required to appropriately etch these metals. Zinc has an additional disadvantage in that it is soft. Also, metals are not transparent at visible light wavelengths and hence it is difficult to align a mask or graphic artwork using metals if the product being masked requires several superimposed pattern layers.