Abstract: A description is given of an extrusion process for the preparation of a low-dust stabiliser, using a subcooled melt as granulation liquid, as well as of novel amorphous modifications of different stabilisers, including 2,2′-methylenebis(4-[1,1,3,3-tetramethylbutyl]-6-benzotriazol-2-yl-phenol), and of the &bgr;-crystalline modification of 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole and of the preparation thereof. The novel process affords products which are easy to handle and which are flowable, and the novel modifications have advantages as regards their preparation, processing and their use as stabiliser.

Abstract: The present invention provides a hydrate of the 4,4′-di-triazinylamino-2,2′-di-sulfostilbene compound having the formula: in which M and M1 independently represent hydrogen, an alkaline-, an alkaline earth metal or ammonium, x is a number within the range of from 1 to 30, and the crystal form of the hydrate (I) being characterised by an X-ray diffraction pattern which is essentially as set out in the accompanying FIGS. 1 to 11; or a mixture containing one or more of the hydrates of the 4,4′-di-triazinylamino-2,2′-di-sulfostilbene compound having the formula (I); processes for the preparation of the new hydrates; and the use of the new hydrates for the preparation of concentrated aqueous formulations of fluorescent whitening agents.

Abstract: A description is given of an extrusion process for the preparation of a low-dust stabilizer, using a subcooled melt as granulation liquid, as well as of novel amorphous modifications of different stabilizers, including 2,2′-methylenebis(4-[1,1,3,3-tetramethylbutyl]-6-benzotriazol-2-yl-phenol), and of the &bgr;-crystalline modification of 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole and of the preparation thereof. The novel process affords products which are easy to handle and which are flowable, and the novel modifications have advantages as regards their preparation, processing and their use as stabilizer.