| Abstract: | Meetings of the Midlands Region, held in the Sports Pavilion, British Celanese Ltd, Spondon, on 4th March 1965, Mr G. Whitehead in the chair; of the London Region, held at the Royal Society, Burlington House, London Wl, on 5th March 1965, Mr C. Barnett in the chair; of the Scottish Region, held in the St Enoch Hotel, Glasgow, on 9th March 1965, Mr B. W. Mills in the chair; of the West Riding Region, held in the Victoria Hotel, Bradford, on 11th March 1965, Dr F. F. Elsworth in the chair; of the Huddersfield Region, held in the George Hotel, Huddersfield, on 16th March 1965, Mr M. Nutton in the chair; and of the Northern Ireland Region, held in the Abercorn Restaurant, Belfast, on 18th March 1965, Mr D. R. Latham in the chair The properties of fluorescent brightening agents, in solution and on the fibre, are discussed with particular reference to their mode of action and their fastness to light. Methods of analysis are described, including paper and thin–layer chromatography and the use of the chromaticity chart. Attention is drawn to the cis–trans rearrangement that occurs with brightening agents of the stilbene type. |
