Showing papers in "Journal of Cosmetic Science in 1994"
Journal Article•
TL;DR: In this paper, a dissolution technique that could be operated at prearranged pH values was developed, and L.a.b. values of dyed felts were recorded before and after extraction, linking dyeing performance to electrolytic dissociation of larvsone and keratin protonation.
Abstract: Bleached wool felts have been dyed with lawsone, and reflectance spectra recorded in the visible region. These spectra were converted to L.a.b. values by computer. A dissolution technique that could be operated at prearranged pH values was developed, and L.a.b. values of dyed felts were recorded before and after extraction. A theory linking dyeing performance to electrolytic dissociation of larvsone and keratin protonation was developed from the results
13 citations
Journal Article•
TL;DR: Capillary electrophoresis (CE) is demonstrated for the determination of the preservative diazolidinyl urea in cosmetic formulations in this paper, which is an improvement over traditionally used methods, which involve derivatization/degradation reactions.
Abstract: Capillary electrophoresis (CE) is demonstrated for the determination of the preservative diazolidinyl urea in cosmetic formulations. The extremely high resolving power of CE separates the compound from other detectable formulation components. This direct method is an improvement over traditionally used methods, which involve derivatization/degradation reactions. Due to complex matrices, the method of standard additions is used for quantitation. A negative charge is effected by the use of borate buffer (pH 9.3), and diazolidinyl urea elutes at ca. 4 minutes with detection at 215 nm
1 citations