Method for generating a rough surface on a polymer or a polyamide membrane for the top layer of a flexible rule

Abstract

A method for generating a rough surface on a polymer or a polyamide membrane for the top layer of a flexible rule comprises pulling a polymer or a polyamide membrane with both surface being smooth from an unfinished roll. A grinding process for grinding one side of the membrane to a rough surface with low reflection rate is carried out by a series of coarse, median, and fine grain-size sand wheels. A cleaning process then wipes off dust and particles generated at the preceding grinding process by a series of brushing components and vacuuming components. The collection of the finished membrane with a rough surface results in a finished roll. By adhering the finished membrane to the reading surface of a flexible rule, the readings and the scale of the rule surface will be fully protected and easily distinguished.

Dependencies are inferred from the claim text.