Application of environmental scanning electron microscopy in the development of detergents and personal products
Environmental scanning electron microscopy enables the observation of samples in their natural state with no preparation. Unilever Research employs this technology in the research and development of detergents and personal products with much success. The results presented are from various studies which demonstrate the versatility and utility of the technique. Vacuum sensitive samples such as microcapsules were successfully characterized, the efficacy of dental products was shown by monitoring an enamel surface before and after treatment, and the performance of an adhesive was assessed by dynamic experimentation. © 1993 Wiley‐Liss, Inc.
Environmental scanning electron microscopy of personal and household products.
The ability to forego sample preparation and to make observation directly in the environmental scanning electron microscope has benefited both household and personal product research at Unilever Research. Product efficacy on biological materials such as microcomedones was easily ascertained. Skin biopsies were examined in a moist state with no sample preparation. Effects of relative humidity on detergents were visually determined by recreating the necessary conditions in the microscope. Effects of cooling rates on the morphology of softener sheet actives that remained on polyester fabric were characterized via dynamic experimentation.
Failure analysis for poor solderability of Au surface of PCB
Nonwetting is one of the common problems and is always rejected in electronic assemblies. ENIG pads of a PCBA exhibited nonwetting after lead-free reflow soldering. With the aid of stereomicroscope, SEM&EDS and XRF, a series of analysis was performed. And after visual inspection, surface and cross section analysis, thickness measurement and solderability test, it can be inferred that oxidation of plating surface was the main reason for nonwetting, and corrosion in Ni plating caused an adverse impact on solderalibity.