Patent GB-884839-A (GB)
Title: Polyamide fibres of improved resistance to ultraviolet radiation
IPC: C08L77/00
Filed: 1959-10-14
Abstract: Polyamide fibres of improved resistance to ultraviolet radiation comprise a thiazole, iminazole or oxazole compound in which two adjacent carbon atoms of the azole ring are at the same time members of a benzene ring and the carbon atom situated between the two hetero atoms of the azole ring is attached to a carbon atom of a further benzene ring, which contains in the o-position in relation to the bond to the azole ring an optionally etherified hydroxy group and may also be further substituted, e.g. by halogen, C1-4 alkyl, C1-4 alkoxy or phenyl.  An N-atom of benziminazole compounds may carry a substituent such as alkyl, hydroxy-alkyl or benzyl.  The azoles may be used in the form of salts or metal derivatives.  For the preparation of the compounds (see Group IV(b)).  About 0,1 to 10%, preferably 0,1 to 2%, by weight of the azole may be incorporated in the polyamide.  In the example, the azole compounds are added to a polyamide spinning mass and extruded.  Compounds specified in the Example are: 2-(21-hydroxyphenyl)-benziminazole, 2-(31-chloro-, 31,51-dichloro-, 51-bromo-and 31,51-dibromo-21-hydroxyphenyl) - benziminazoles, 2 - (21 - hydroxyphenyl) - 6 - methylbenziminazole, 2-(21-hydroxyphenyl)-1-methylbenziminazole, 2 - (31 - chloro, 31,51 - dichloro -, 51 - bromo-, and 31,51-dibromo-21-hydroxyphenyl)-benzoxazoles, 2 - (21 - hydroxyphenyl) - benzoxazole, 2-(31-chloro-, 31,51-dichloro-, and 31-methyl-21-hydroxyphenyl)-5-methylbenzoxazole, 2-(21 - hydroxyphenyl) - 5 - methylbenzoxazole, 2 - (21 - hydroxyphenyl) - 5 - chlorobenzoxazole, 2 - (31 - chloro-, 31, 51 - dichloro, - 51 - bromo -, and 31, 51 - dibromo - 21 - hydroxyphenyl) - 5 - chlorobenzoxazoles, 2 - (51 - chloro-, 51 - bromo-, and 31,51 - dibromo - 21 - hydroxyphenyl)-4,5,7-trichlorobenzoxazole, 2 - (21 - hydroxyphenyl)-5-phenylbenzoxazole, 2 - (21 - hydroxyphenyl) - benzthiazole, 2 - (31,51 - dichloro - 21 - hydroxyphenyl) - benzthiazole, the phosphate and halfphosphate salts of 2-(21-hydroxyphenyl) - benziminazole, the O-sodium, and O, N-disodium derivatives of 2-(21-hydroxyphenyl)-benziminazole, the O,N-disodium derivatives of 2-(31,51-dichloro-, and 51-bromo-21-hydroxyphenyl)-benziminazole, 2 - (21 - methoxyphenyl) - benziminazole, and 2-(21-methoxyphenyl)-5-methyl-benzoxazole.ALSO:Benziminazole, benzoxazole and benzthiazole derivatives having in the 2-position an o-hydroxy- or o-(etherified hydroxy)-phenyl group and which may contain further substituents, particularly, halogen atoms, or lower alkyl, lower alkoxy, or phenyl radicals, and salts and metal derivatives thereof, are used as ultra-violet light absorbers.  An N-atom of benziminazoles may carry a substituent such as an alkyl, hydroxyalkyl or benzyl group. Suitable preparative methods include the heating of o-amino-hydroxyaryl compounds or o-diamino-aryl compounds with benzene-o-hydroxycarboxylic acids or their functional derivatives, perferably in the presence of agents capable of splitting out water such as boric acid or polyphosphoric acid; solvents may be used.  Alternatively acyl compounds derived from benzene-o-hydroxycarboxylic acids and o-aminohydroxy-benzenes or o-diaminobenzenes may be heated and/or treated with an agent capable of splitting out water; zinc chloride is an additional agent suitable in this reaction.  Compounds prepared in the example are: 2 - (21 - hydroxyphenyl) - benziminazole, 2 - (31 - chloro-, 31,51-dichloro-, 51-bromo-, and 31,51-dibromo - 21 - hydroxyphenyl) - benziminazoles, 2 - (21 - hydroxyphenyl) - 6 - methylbenziminazole, 2 - (21 - hydroxyphenyl) - 1 - methylbenziminazole, 2-(31-chloro-, 31,51-dichloro-, 51-bromo-, and 31,51-dibromo-21-hydroxyphenyl) - benzoxazoles, 2 - (21 - hydroxyphenyl - benzoxazole, 2-(31-chloro-, 31,51-dichloro-, and 31 - methyl - 21 - hydroxyphenyl) - 5 - methylbenzoxazoles, 2-(21-hydroxyphenyl)-5-methylbenzoxazole, 2 - (21 - hydroxyphenyl) - 5 - chlorobenzoxazole, 2-(31-chloro-, 31,51- dichloro-, 51-bromo-, and 31,51 - dibromo - 21 - hydroxyphenyl) - 5 - chlorobenzoxazoles, 2 - (51-chloro-, 51-bromo-, and 31,51-dibromo-21-hydroxyphenyl) - 4,5,7 - trichlorobenzoxazole, 2 - (21 - hydroxyphenyl) - 5 - phenylbenzoxazole, 2 - (21 - hydroxyphenyl) - benzthiazole, 2 - (31,51 - dichloro - 21 - hydroxyphenyl) - benzthiazole, the phosphate and half-phosphate salts of 2-(21-hydroxyphenyl) - benziminazole, the O-sodium and O,N-disodium derivatives of 2-(21-hydroxyphenyl)-benziminazole, the O,N-disodium derivatives of 2-(31,51-dichloro-, and 51-bromo-21-hydroxyphenyl) - benziminazole, 2 - (21 - methoxyphenyl)-benziminazole, and 2-(21-methoxyphenyl)-5-methyl-benzoxazole.