Patent ID: 7449336
Filing Date: 2008-11-11
Classification: G01N

Abstract:
1. A method for testing for the presence of a coating, the method comprising: testing for the presence of a sol-gel coating on a metal surface; placing a test specimen of unknown coating in a solution in a first receptacle; placing a conversion-coated control specimen in the solution in a second receptacle, wherein the conversion-coated control specimen has a leached alodine coating; placing a sol-gel-coated control specimen in the solution in a third receptacle, wherein the sol-gel-coated control specimen has a leached alodine plus sol-gel coating; observing a first length of time for the test specimen to change color; observing a second length of time for the conversion-coated control specimen to change color; observing a third length of time for the sol-gel-coated control specimen to change color; and determining a presence or absence of the coating on the test specimen based on comparison of the first length of time, the second length of time, and the third length of time.