Thursday, September 10, 2009

Surface UV Fluorescence Detection

Question: Can UV Fluorescence be used for soil detection?

Answer:

Surface Ultraviolet (UV) Fluorescence—Many organic and some inorganic contaminants will fluoresce under UV light. Shining a UV light on the surface makes residues more visible, particularly in a slightly darkened or dark room. The higher the intensity of the light used, the lower the level of contaminants easily detected. Note, however, that the typical black light found in novelty or specialty gift stores may not be strong enough to cause much residue to fluoresce. More powerful UV lights, available from scientific supply houses or industrial suppliers, will provide far better results. The test is performed by shining the light on the surface and observing an easily seen, fluorescent—typically a yellow, orange or green, sometimes red—color which glows under the light.


Contact Alconox technical support for selecting the right aqueous critical cleaner!


Alconox, Inc manufactures a range of aqueous critical cleaners from powder to liquid, acid to alkaline, highly emulsifying to low foaming. GMP compliant brands are available globally. Downloadable certificates of analysis (COA), MSDS, technical bulletins and trace analysis from the Alconox website at www.alconox.com

Tuesday, September 08, 2009

Nonvolatile Residue Inspection

Question: What is a nonvolatile residue inspection?

Answer:

Nonvolatile Residue Inspection (NVR)—involves extraction of soil from a dirty surface into a solvent. The solvent is then evaporated onto a coupon of known weight after the solvent is evaporated off the coupon, any residue will be deposited on the coupon. The coupon is then re-weighed and any weight increase detected is attributed to the nonvolatile residue. Many solvents can be used for this purpose. It is important to use a solvent that can dissolve the soil being detected. (Isopropyl alcohol, methylene chloride, acetone and other solvents have been used for this purpose.)

To get more information on how to measure cleanliness, contact Alconox Critical Cleaning Experts at cleaning@alconox.com

Thursday, September 03, 2009

Water Break Test

Question:
Is a water break test similar to an atomizer test?

Answer:
Water-break test- uses running water, allowing it to form a sheet, across the surface. Breaks in the water indicate the presence of hydrophobic (water-fearing) residues. (See "The Hydrophobic Surface Film by the Water Break Test," ASTM Method F 22-65-found at astm.org) The water break test is a fairly crude test which is suitable for detecting films of process oils and heavy fingerprints. It does not readily detect non-hydrophobic residues. This test is often used for parts washing and may not be suitable for precision cleaning applications.

Atomizer test- a variation of the water-break test, involves a gently sprayed water mist. Any areas, where water repulsion occurs, indicate the presence of a hydrophobic soil. The atomizer test is slightly more sensitive to hydrophobic soils than the water break test in which the kinetic energy of the flowing water may overcome a hydrophobic residue. In contrast, the atomizer test allows you to see a small droplet of water being repelled by a hydrophobic contaminant.

With over 60 years of experience in detergent manufacturing, talk to the critical cleaning experts at Alconox to solve your most difficult cleaning challenges. Contact the Critical Cleaning Experts at cleaning@alconox.com.