Apparatus and method of foam dyeing a traveling sheet of textile yarn

Abstract

Dyeing a traveling sheet of textile yarn with a dye in foamed condition, and, more particularly, dyeing by separating a traveling sheet of yarn into separate spaced portions and applying foamed dye to the inner facing and outer facing surfaces of the yarns in the spaced portions. Then recombining the spaced portions into a single sheet and further applying foamed dye to the yarn in the recombined sheet.

1 . An apparatus for dyeing a traveling sheet of textile yarns with dye applied in a foam condition, comprising:
 a pair of driven infeed nip rollers for feeding said sheet of yarn in a downstream direction;   a pair of outwardly spaced guide rollers downstream of said infeed rollers for guiding separated portions of said yarn sheet in separated spaced paths;   a pair of driven yarn sheet recombining nip rollers downstream of said outwardly spaced rollers for recombining said separated yarn sheet portions into a single yarn sheet;   an exit guide roller downstream of said recombining nip rollers for guiding said recombined yarn sheet from said apparatus;   a pair of outwardly facing, inner foam applicators and a pair of inwardly facing, outer foam applicators, said pairs spaced from each other in the downstream direction of travel of said yarn sheet;   said pair of outwardly facing, inner foam applicators disposed between the paths of said separated yarn sheet portions and having foam dispensing nozzles extending transversely of and in contact with the inner facing surfaces of the yarns of said separated yarn sheet portions for surface dyeing of the inward facing surfaces of said separated yarn sheet portions;   said pair of inwardly facing, outer foam applicators disposed outwardly of the path of yarn travel and having foam dispensing nozzles extending transversely of and in contact with the outer facing surfaces of the yarns for surface dyeing of the outward facing surfaces of said yarn;   
     
     
         2 . The apparatus for dyeing a traveling sheet of textile yarns according to  claim 1  and characterized further by a plurality of foam applicators downstream of said recombining rollers and having nozzles for applying foamed dye to the yarns in said recombined sheet of yarns. 
     
     
         3 . The apparatus for dyeing a traveling sheet of textile yarns according to  claim 1  and characterized further in that said outwardly facing, inner applicators are located between said outwardly spaced guide rollers and said recombining rollers, and said inwardly facing, outer applicators are located between said outwardly spaced rollers and said outwardly facing, inner applicators. 
     
     
         4 . The apparatus for dyeing a traveling sheet of textile yarns according to  claim 1  and characterized further in that said outwardly facing nozzles of said inner foam applicators project into the paths of said separated yarn sheet portions to deflect the yarn sheet portions outwardly to maintain foam dispensing contact therewith; and said inwardly facing nozzles of said outer applicators project into the path of said yarn to deflect the yarn inwardly to maintain foam dispensing contact therewith. 
     
     
         5 . The apparatus for dyeing a traveling sheet of textile yarns according to  claim 1  wherein said textile yarns are undyed cotton yarns and the dye applied by said applicators is indigo leuco-state dye, and characterized further by
 a dyeing chamber sealed from atmospheric air and having entry and exit seals through which said yarn sheet enters and exits said chamber; 
 a supply of inert gas communicating with said chamber to maintain a substantially inert atmosphere therein; 
 said pair of infeed nip rollers are disposed in said chamber for feeding said sheet of yarn in said chamber in a downstream direction; 
 said pair of outwardly spaced guide rollers are in said chamber downstream of said infeed rollers; 
 said pair of yarn sheet recombining nip rollers are in said chamber downstream of said outwardly spaced rollers; 
 said exit guide roller is outside said chamber, downstream of said recombining nip rollers for guiding said recombined yarn sheet through said exit seal and from said chamber; and 
 said pairs of foam applicators are in said chamber. 
 
     
     
         6 . The apparatus for dyeing a traveling sheet of textile yarns according to  claim 5  and characterized further in that said outwardly facing, inner applicators are located between said outwardly spaced guide rollers and said recombining rollers, and said inwardly facing, outer applicators are located between said outwardly spaced rollers and said outwardly facing, inner applicators. 
     
     
         7 . The apparatus for dyeing a traveling sheet of textile yarn according to  claim 5  and characterized further in that a plurality of additional pairs of applicators are disposed in said chamber downstream of said recombining nip rollers, each additional pair having one applicator with a nozzle extending transversely of and in contact with one surface of said yarn sheet, and the other applicator of each additional pair of applicators spaced downstream of said one applicator with a nozzle extending transversely of and in contact with the opposite surface of said yarn sheet for supplemental dyeing of said yarn sheet. 
     
     
         8 . The apparatus for dyeing a traveling sheet of textile yarn according to  claim 7  and characterized further in that the nozzles of said additional applicators project into the path of said yarn to deflect the yarn to maintain foam dispensing contact therewith. 
     
     
         9 . A method of dyeing a traveling sheet of textile yarns with foamed dye, comprising
 continuously feeding the sheet of yarn in a single path;   separating said traveling sheet into two separate spaced sheet portions for continuing travel in separate spaced path portions, with the yarns in each separate spaced path portion having surfaces facing the other sheet portion and surfaces facing away from the other sheet portion, and having interior portions;   applying foamed dye to said surfaces of the yarns in said separate sheet portions;   said separating reducing the density of said yarns in each separate portion of said yarn sheet, thereby reducing substantially the likelihood of any white spots remaining on any of said yarns due to overlapping or entangling during said applying foamed dye to said yarn surfaces;   recombining said separate sheet portions for continued travel as a single sheet.   
     
     
         10 . The method of dyeing a traveling sheet of textile according to  claim 9  and characterized further by applying foamed dye to the yarns in the traveling recombined sheet of yarns. 
     
     
         11 . The method of dyeing a traveling sheet of textile yarns according to  claim 10  wherein the dye applied by at least one of said applying foamed dye is from a different source than the source of dye applied by other dye applying. 
     
     
         12 . The method of dyeing a traveling sheet of textile yarns according to  claim 10  and characterized further in that the applying foamed dye to the yarns in said separate sheet portions applies dye to tint the surfaces of the yarns, leaving said interior portions of the yarns undyed, and said dyeing of the yarns in the recombined sheet applies dye to deepen the shade of the dye applied to the yarn in the separate sheet portions. 
     
     
         13 . The method of dyeing a traveling sheet of textile yarns according to  claim 9  wherein the yarn is undyed cotton yarn and the yarn is fed through a sealed chamber containing an inert gas and said yarn sheet separating and recombining are within the chamber and the foamed dye is indigo dye in a leuco-state and is applied to said yarns in said chamber. 
     
     
         14 . The method of dyeing a traveling sheet of textile according to  claim 13  and characterized further by applying foamed dye to the yarns in the traveling recombined sheet of yarns in said chamber. 
     
     
         15 . The method of dyeing a traveling sheet of textile yarns according to  claim 14  wherein the dye applied by at least one of said applying foamed dye is does from a different source than the source of dye applied by other dye applying. 
     
     
         16 . The method of dyeing a traveling sheet of textile yarns according to  claim 14  and characterized further in that the applying foamed dye to the yarns in said separate sheet portions applies dye to tint the surfaces of the yarns, leaving the interior portions of the yarns undyed, and said dyeing of the yarns in the recombined sheet applies dye to deepen the shade of the dye applied to the yarn in the separate sheet portions.