Patent ES-340439-A1 (ES)
Title: Mechanical Surface Texturing of Fabrics
IPC: D06C11/00
Filed: 1967-05-12
Abstract: The surface texture of a fabric is modified by passing the fabric into contact with an abrasive surface moving relative to the fabric to cause loosening, breaking and removal of an appreciable quantity of fibres and simultaneously raising, fluffing and blending the surface fibres on the fabric face. As shown, a fabric 10, e.g. a yarn-dyed allcotton twill having an upper face 12 which is predominantly warp ends of a different colour from the weft, is fed from a cart 14 over an idle roller 44, around tension bars 40, between nip rollers 18, around a steam can 42 guided by idle rollers 46, 48, around a pressure roller 26, against the surface of an abrading roller 22, around an idle roller 53, under a tension bar 58, between nip rollers 20 and around an idle roller 60 to a folding device 24 which lays the abraded fabric on a cart 16. The rollers 18, 20 are driven by a variable speed electric motor 28 through connections 30, 32. A variable speed transmission 34 is included in the connection 32 and is adjusted so that the rollers 18 are driven at a slower peripheral speed than the rollers 20 to tension the fabric. The folder 24 is also driven by the motor 28. The roller 22 is driven at a constant high speed in the direction opposite to that in which the fabric travels by an electric motor 50 and comprises either a metal roller carrying abrasive particles on its surface or a solid abrasive which includes carborundum. The roller 22 may be cooled internally, e.g. by being constructed as a hollow cylinder with liquid therein. The roller 26 is adjustable horizontally by a horizontally slotted arm 54 at each end of the roller 22, the arms being secured by bolts to a fixed support 56. A suction hood 57 is provided to remove flock and dust from the fabric 10. If desired, the fabric 10 may be turned over and run through the apparatus again or a second abrading roller and pressure roller may be provided to grind the lower face of the fabric. Alternatively, the fabric may be a blend of cotton with 35-65% polyester fibres or may be entirely of synthetic fibres. The fabric may contain yarns which have been dyed with a deeply penetrating dye the penetration of which has been limited so as to leave the centres of the yarns undyed. Prior to abrading, the fabric may have been dry finished, e.g. brushed, tentered or sheared, or wet finished, e.g. sized or resin impregnated either of the pre-cure or post-cure type to impart crease resistance. The invention is applicable to modifying the surface texture of a blue denim fabric to give it a seasoned, well-worn mottled appearance and feel. As shown in Fig. 2, raw yarn 100 in the form of bundles or chains wound on a package 102 is passed through a dye tank 104 containing a chemically reduced solution of an indigo blue dye. The natural oils and waxes in the yarn effect an uneven absorption of the dye so that the dyed yarn is not uniform in colour along its length or in its tendency to retain the dye. The wet yarn passes over an elevated roller 106 along a long path to effect oxidization of the soluble form of the dye to its insoluble form. The yarn 100 passes into a second dye tank 108, over a roller 110, through a rinse bath 112 and is dried by passing over heated drums 114. A blue warp face twill fabric 116 is woven at 118 using the yarn 100 as warp and a white or grey weft yarn and has light and dark areas of irregular shape and size. The fabric 116 passes through a bleaching bath 120, e.g. an aqueous solution containing 1.0% soda ash and 0.05% sodium hyperchlorite and a combination of peanut oil and auxiliaries in addition to a fatty base derivative used as a sewing lubricant. Other bleaching agents, e.g. aqueous solutions containing chlorine dioxide or hydrogen peroxide, may be used. The fabric 116 then passed around heated drying drums 122, through apparatus 8 of the type shown in Fig. 1 to abrade the warp face thereof and is shrunk by a machine comprising a heated cylinder 124 and a tensioned rubber belt 126.