| 摘要 |
1,253,478. Crease resistance. J. A. PINATEL. 8 June, 1970, No. 27660/70. Heading DIP. A process for treating fabrics, e.g. cotton and synthetic fibres with an elastomeric organo siloxane composition capable of vulcanizing at room temperature in the presence of moisture. Suitable organo siloxanes are where Ac is a saturated aliphatic monoacyl radical of a carboxylic acid; R is selected from the group consisting of monovalent hydrocarbon radicals, halogenated monovalent hydrocarbon radicals and cyano alkyl radicals and n is >5 and generally 20-5000 for a convenient viscosity. The siloxane may be applied from a solution or emulsion by dipping, spraying or padding and the fabric contains 1-5 ounces of polysiloxane per sq. yd. For application to the fabric the siloxane can be diluted as required with an inert organic solvent and a 20% by wt. solution is satisfactory. After impregnation the fabric is passed through a drying oven at 140-150‹F., leaving 10-15% by wt. of solvent on the fabric. The fabric is then ready for finishing and can either be immediately made into end products or stored for future use in an air and moisture tight enclosure. The cut and sewn product is then finished in the vulcanizing step in which the fabric is either subjected to wet steam atmosphere for 15-20 minutes or placed in a hot steam and vacuum press. In such a press the product may be subjected to 20 secs. of steam, followed by 10 sees. of 5000 lbs./sq. in. pressure and 5 secs. of vacuum, these steps overlapping one another if desired. The product is then aged by hanging in a moist atmosphere for 2-3 hours to allow the curing process to be completed by expelling all of the solvent. A preferred siloxane is the reaction product of dimethylpolysiloxane and an acyl oxysilane of general formula R Si(OAc) 3 . |
