Cleaning Copper Optical Molds

Q. The ammonia-peroxide solution (also known as Standard Clean 1 or SC1) is a very effective cleaner on our nickel optical molds, but we cannot use that cleaner on our new copper optical molds. The SC1 solution is very corrosive to copper. So we would like to find another cleaner that we could use for both copper and nickel parts. We are mostly removing machining fluid and particulates. Our parts have a very tight spec on particulates. We need to have essentially no particulates greater than 10 um, and this is inspected with a microscope. Obviously, the ammonia-peroxide solution is moderately dangerous to work with, and disposal is expensive. We go through at least 55 gallons per month of the ammonia-peroxide solution, it is quite a hassle.

A. Your question holds much complexity, but the answer is rather simple. For cleaning copper and nickel molds in ultrasonic tanks we recommend using a warm or hot 2% Citranox® solution (2.5 oz/gal or 20 mL/L) followed by a thorough rinse with particle filtered water. For more technical information on Citranox® detergent, click these links for the Safety Data Sheet and Technical Bulletin.