Reference

Evaluation of the total content of polycyclic aromatic hydrocarbons in synthetic cosmetic dyes

Evaluation of the total content of polycyclic aromatic hydrocarbons in synthetic cosmetic dyes. Maslowska, Joanna; Bazylak, Grzegorz (Inst. Podstaw Chem. Zywnosci, Politech. Lodzkiej, Lodz, Pol.). Pollena: Tluszcze, Srodki Piorace, Kosmet., 28(11-12), 207-11 (Polish) 1984. CODEN: PTSKDF. DOCUMENT TYPE: Journal CA Section: 62 (Essential Oils and Cosmetics) Polycyclic arom. hydrocarbons were detected by TLC in 20 synthetic dyes used as raw materials for cosmetic products in concns. 0.06-10.0 mg/kg. The cancerogenic hydrocarbon chrysene [218-01-9] was found in Fast Orange [842-07-9], Toluidine Red [2425-85-6], and Rhodamine B [81-88-9]; and benzo[a]pyrene [50-32-8] was found in Fast Red R [2425-85-6], Lithol Red B [1248-18-6], and Quinoline Yellow [8004-92-0].

Studies of the kinetics of nucleation and growth of pigment dispersions using a laser light-scattering apparatus in a flow system

Studies of the kinetics of nucleation and growth of pigment dispersions using a laser light-scattering apparatus in a flow system. Nobbs, James H.; Patterson, David (Dep. Color Chem. Dyeing, Univ. Leeds, Leeds, Engl.). J. Chem. Soc., Faraday Trans. 1, 73(4), 558-68 (English) 1977. CODEN: JCFTAR. DOCUMENT TYPE: Journal CA Section: 42 (Coatings, Inks, and Related Products) A continuous coupling flow system was developed to det. and study the factors that influence particle shape and size during prodn. of azo pigments. Data on the av. particle size was obtained by measurement of the angular dependence of laser light scattered on passing radially through the flow tube. The growth of particles was monitored from nucleation to the final particle size. An alternative to the Zimm plot method was used to analyze the light scattering data; the effects of particle concn., shape and size distribution on the scattering intensities were taken into account. The particle growth rate in the coupling of Toluidine Red [2425-85-6] pigment was 1st order and decreased with temp., the final particles were rod shaped and of similar size. The limiting size to which a nucleus can grow depends only on the concn. of pptd. mols. within a fixed vol. surrounding the nucleus.