TAPES AND METHODS OF USE FOR MASKING ALUMINUM SURFACES IN CHROMIC ACID ANODIZATION

A tape includes: a flexible backing layer having two major surfaces, wherein the backing layer has a thickness of greater than 64 micrometers and up to 200 micrometers, and one major surface of the backing layer includes a primed surface; and a rubber-based pressure sensitive adhesive layer disposed on the primed surface of the backing layer, wherein the pressure sensitive adhesive layer has a thickness of at least 7.6 micrometers (and preferably up to 25 micrometers); wherein, when disposed on an aluminum substrate, the tape displays a peel adhesion of less than 20 oz/in (219 N/m) according to a Peel Adhesion Strength Test described in the Examples Section, and a leakage distance of less than 762 micrometers according to a Chromic Acid Anodization-Leakage Distance Test described in the Examples Section. A method of anodizing an aluminum surface includes: providing a substrate having an aluminum surface; applying a tape as described herein to mask the aluminum surface and form a masked substrate; and exposing the masked substrate to an electrolyte solution including chromic acid under conditions effective to form aluminum oxide.