Detergents

Q. Our current cleaning process has a tendency to leave spots on board and component leads. Analysis of the white spots shows oxides of tin and lead; rust-colored spots show iron oxide. FTIR analysis shows no organic content, so it’s not soap, flux, etc. I have recommended that the production people use appropriate Alconox, LLC cleaner or possibly DI water only for a very short cleaning cycle, and that they dry the boards promptly in flowing warm air. Rust is coming from tinned steel component leads. C

Q. Which Alconox detergents can best clean glass or metal that has a photovoltaic surface? A. Thin film solar module manuf

Q. Can I use pH paper to confirm cleaning and rinsing of labware to comply with lab accreditation requirements?

A. If you are going to use pH strips to comply with lab accreditation requirements, you need to verify that your detergents are not interfering with the strips and papers. Detergents and surface active agents can interfere with some pH paper by causing a decrease of several pH units in reading. Please test any pH paper you intend to use …

Q. I am developing a new cleaning process to replace the process we are using for cleaning glass slides before applying Silane coating. We are using strong acid to clean glass slides. I want to use a process where I first use basic aqueous solution, then use DI water to rinse, followed by acidic solution to chelate away metal ions. Then we’ll do DI water rinse, air dry, and finally use oxygen plasma to final clean the glass slide. What acidic aqueous solution and basic aqueous solution can you suggest?

Q. We need recommendations for cleaning stainless steel weldments. A Walter weld cleaning machine is being used. We have tried using Luminox® but sometimes it does not produce satisfactory results.

A. Luminox® is a very light duty cleaner used to remove light oils and tiny particulates from delicate substrates. Generally, stainless steel is not considered a delicate substrate. In this case…