GB600113A - Improvements relating to processes for spinning artificial silk from viscose in an acid spinning bath - Google Patents

Abstract

In the production of filaments, fibres, threads and the like from viscose by extrusion into an acid spinning bath a small amount of a compound of general formula <PICT:0600113/IV(a)/1> wherein R and R1 may be aliphatic or aromatic radicles, the chain of which excluding aromatic or other nucleus has a length of at most 6 C-atoms, or R1 may be hydrogen, X may be OH or a monovalent acid radicle and the pyridine may be substituted or may be a homologue of pyridine is added to the spinning bath or spinning solution, to prevent blocking of the spinning nozzles. These compounds are stable in both acid and alkaline solutions and will not cause foam-formation on concentration of the bath by evaporation since they are not surface-active. In an example 0.1 per cent of N(a -furyl-21; hydroxy-21; phenyl-11; ethyl)-1 pyridinium bromide is dissolved in a spinning bath containing 50 g. zinc sulphate per litre in addition to the normal quantities of sodium sulphate and sulphuric acid. After spinning for 1 hour 80 per cent of the orifices were unblocked, whereas when spinning under the conditions without the addition all orifices were blocked. In a further example 0.1 per cent of N(phenyl-21; hydroxy-21; vinyl-11; ethyl(-1-pyridinium) bromide was added to viscose which was then spun into a bath containing usual amounts of sodium sulphate and sulphuric acid and 50 g. of zinc sulphate per litre. As in the previous example, 80 per cent of the orifices were clear after spinning for 1 hour. Preparation of additives.-These compounds may be prepared from pyridine or one of its homologues or derivatives, an alkyl halide and an aldehyde. For example, N(a -furyl-21; hydroxy-21; phenyl-11; ethyl)-1-pyridinium bromide is prepared by adding an equivalent amount of furfural to benzyl-pyridinium bromide in ethanol. 10N sodium lye is added and the mixture left at 0 DEG C. for 5 days, the separated product being then washed with alcohol, purified with decolorising carbon and recrystallized from water. The compounds may also be prepared by reacting styrene bromohydrin with homologues or derivatives of pyridine.ALSO:Compounds of general formula <FORM:0600113/IV(b)/1> wherein R and R1 may be aliphatic or aromatic radicles, the chain of which excluding aromatic or other nucleus has a length of at most 6 C-atoms, or R1 may be hydrogen, X may be OH or a monovalent acid radicle and the pyridine may be substituted or may be a homologue of pyridine are added to viscose spinning solutions. These compounds may be prepared from pyridine or one of its homologues or derivatives, an alkyl halide and an aldehyde. For example, N(-furyl-21; hydroxy-21; phenyl-11; ethyl)-1-pyridinium bromide is prepared by adding an equivalent amount of furfural to benzylpyridinium bromide in ethanol. IO N sodium lye is added and the mixture left at 0 DEG C. for 5 days, the separated product being then washed with alcohol, purified with decolorising carbon and recrystallised from water. The compounds may also be prepared by reacting styrene bromohydrin with homologues or derivatives of pyridine.