GB450198A - Improvements in dyeing processes - Google Patents

Abstract

Silk, cotton goods, yarns, or the like material is dyed by subjecting it in a suitable chamber to a vacuum, introducing the dye liquor into the chamber from a reservoir under vacuum, and then introducing air under atmospheric pressure into the chamber to force the liquor into the fibres of the material. The liquor may be returned to the reservoir by the atmospheric pressure in the chamber, and the dyed material may be centrifuged without removing it from the chamber. If desired, during the centrifuging treatment of the material in one impregnating chamber, the dye liquor from the reservoir may be treated in a second chamber. The apparatus employed may comprise a number of <PICT:0450198/IV/1> dyeing chambers 8, 10 and a dye liquor reservoir 11. Each chamber 8, 10 comprises a cylindrical shell 16 with a corrosion-resisting lining and a spherical bottom forming a sump 18. Conduits 20, controlled by valves 21, 22, control the flow of liquor between the reservoir 11 and the chambers 8, 10. The top of the reservoir 11 is integral with the chamber and is provided with a manhole 24 and cover 26, and a vacuum may be established therein by a conduit 29 connected to a vacuum line, and a valve 30. The removable covers 31 of the chambers 8, 10 carry conduits 38 having valves 36, 39 adapted to engage a vacuum line. A centrifuge 37 comprising a perforated basket secured to a rotatable shaft 40 driven by bevel gears 51, 52 is disposed in each chamber 8, 10. The baskets are filled with the material to be dyed and the chamber 11 is fitted with dye liquor. The valves 21, 22 are closed and the chambers 8, 10 and reservoir 11 are evacuated until a high vacuum has been obtained. The valves 30, 36, 39 are then closed and valve 21 is opened to allow the dye liquor to run into the chamber 8 and is forced into the material by closing valve 21 and opening the valve 36 to admit air under atmospheric pressure. After a period for treatment the valve 21 is opened and the dye liquor is forced by the air pressure in the chamber 8 through the conduit 21 into the reservoir 11. The valve 21 is next closed and the material is centrifuged to remove excess liquor. The dye liquor in the reservoir 11 is subjected to a vacuum before each treatment.