Patent GB-813289-A (GB)
Title: Improvements in or relating to the treatment of textile fabrics
IPC: D06M11/11
Filed: 1956-09-26
Abstract: A heat-set knitted or woven fabric consisting at least in part of polyamide fibres is treated with an aqueous solution of an inorganic swelling agent for the polyamide containing up to 50 per cent (by weight of the solution) of an organic solvent which is at least partly soluble in water, the fabric being thereafter washed to remove inorganic swelling agent and dried.  The washing may be preceded by a preliminary drying of the fabric at a temperature such that no substantial reaction of the fabric with the swelling agent occurs. As inorganic swelling agent there may be used a salt, e.g. zinc or calcium chloride, calcium thiocyanate or lithium bromide, or an acid, e.g. hydrochloric, sulphuric, nitric or phosphoric acid.  The organic solvent may be an alcohol, preferably monohydric, e.g. butyl, amyl or benzyl alcohol or cyclohexanol, or an aldehyde, e.g. acetaldehyde or furfural, or a ketone, e.g. cyclohexanone.  Preferably the proportion of organic solvent is 0.1-10 per cent by weight of the aqueous solution of swelling agent, and treatment is carried out for 5-90 seconds. Patterned effects may be obtained by treating the fabric pattern-wise with the aqueous solution, which may then be applied, mixed with a thickening agent (e.g. water-soluble methyl cellulose), as a viscous mass.  Alternatively, the fabric may be treated with a resist composition, which may contain an alkylated aminoplast resin, e.g. a butylated urea-formaldehyde resin, or the sodium salt of polyacrylic acid, prior to treatment with the aqueous solution, and the resist may be subsequently removable by washing.  The treatment improves appearance and handle, reduces the tendency of staple fibre fabrics to "pilling," and may be used to obtain dull and stiffening effects.  In an example, a scoured, heat-set, bleached and dried nylon voile is dipped for 6 seconds into a bath containing 455 g. hydrochloric acid, 445 g. water, and 100 g. diacetone alcohol and is then washed with cold water and dried under tension.  The fabric is found to be stiffened and dull, while the opacity of individual fibres is increased.ALSO:A heat-set knitted or woven fabric consisting at least in part of polyamide fibres is treated with an aqueous solution of an inorganic swelling agent for the polyamide containing up to 50 per cent (by weight of the solution) of an organic solvent which is at least partly soluble in water, the fabric being thereafter washed to remove inorganic swelling agent and dried. The washing may be preceded by a preliminary drying of the fabric at a temperature such that no substantial reaction of the fabric with the swelling agent occurs.  As inorganic swelling agent there may be used a salt, e.g. zinc or calcium chloride, calcium thiocyanate or lithium bromide, or an acid, e.g. hydrochloric, sulphuric, nitric or phosphoric acid.  The organic solvent may be an alcohol, preferably monohydric, e.g. butyl, amyl or benzyl alcohol or cyclohexanol, or an aldehyde, e.g. acetaldehyde or furfural, or a ketone, e.g. cyclohexanone.  Preferably, the proportion of organic solvent is 0.1-10 per cent by weight of the aqueous solution of swelling agent, and treatment is carried out for 5-90 seconds. Patterned effects may be obtained by treating the fabric pattern-wise with the aqueous solution, which may then be applied, mixed with a thickening agent (e.g. water-soluble methyl cellulose), as a viscous mass. Alternatively, the fabric may be treated with a resist composition, which may contain an alkylated butylated urea-formaldehyde resin, or the sodium salt of polyacrylic acid, prior to treatment with the aqueous solution, and the resist may be subsequently removable by washing.  The treatment improves appearance and handle, reduces the tendency of staple fibre fabrics to "pilling," and may be used to obtain dull and stiffening effects.  In an example, a scoured, heat-set, bleached and dried nylon voile is dipped for 6 secs. into a bath containing 455 g. hydrochloric acid, 445 g. water, and 100 g. diacetone alcohol and is then washed with cold water and dried under tension.  The fabric is found to be stiffened and dull, while the opacity of individual fibres is increased.