Processes and apparatus are disclosed which substantially eliminate the formation of oxidized indigo dye before and during dye application onto a natural fiber yarn or fabric while allowing the leuco-indigo dye molecule to diffuse fully into the natural fibers of the yarn where it can fix to the fibers prior to oxidation (i.e., exposure of the leuco-dyed yarns to oxygen). Indigo dyed textile products (e.g., dyed cotton yarns that may be twill woven to form a denim fabric) exhibit exceptionally high colorfastness as determined by the AATCC Crock Test.

A dyeing machine comprising at least one dyeing module in which a first squeezing device for a textile support, a first treatment tank, a central tank, a second treatment tank and a second squeezing device are located in sequence is described. The dyeing machine also includes a hydraulic system for feeding, circulating and alternately adjusting the levels of process fluids in the tanks. The tanks are preferably enclosed in a hermetically sealed upper covering shell. The two treatment tanks have the same shape, the same dimension and capacity characteristics, and are symmetrical with respect to a plane of symmetry lying in the central tank and arranged perpendicularly with respect to the direction of advance of the textile support. The dyeing machine is provided with means for moving the textile support, configured to advance the textile support alternately in both directions, i.e. either from the first squeezing device to the second squeezing device, sequentially through the tanks, or from the second squeezing device to the first squeezing device, again sequentially through the tanks.

The present invention refers to a plant (1) for printing a fibrous material (T). The printing plant (1) comprises: a station (14) for supplying a fibrous material configured for supplying the fibrous material along a predetermined operative path, a treating station (10) configured for treating the fibrous material with a treatment composition by applying the composition itself on a first side (T1) of the fibrous material (T); and a printing station (6) configured for ink-printing at least part of a second side (T2) of the fibrous material (T) opposite to the first side (T1). Moreover, the present invention refers to a process of printing a fibrous material.

Systems and methods are described whereby a deoxygenated liquid dye material is made by supplying the deoxygenated inert gas to a liquid dye material that is susceptible to oxidation, and mixing the liquid dye material in the presence of the supplied deoxygenated inert gas with water and at least one dye formulation component selected from the group consisting of reducing agents, pH adjusters, foaming agents, wetting agents and auxiliary chemicals to form a deoxygenated aqueous dye composition having an oxygen content of 30 ppm oxygen or less. A supply of inert gas may be provided which is then passed to a gas purifier to reduce oxygen content in the inert gas to, e.g., 1 ppb oxygen or less. The deoxygenated aqueous dye composition that is formed may have an oxygen content of 1 ppm or less.

A device for applying a foamed treating material under pressure to a traveling sheet of relatively incompressible textile yarns. A foam applicator unit has a nozzle with a foam dispensing slot facing across one side of the traveling sheet of yarns. A drive roll faces the other side of the traveling sheet of yarns in tangential alignment with the foam dispensing slot. The roll has a resiliently compressible, soft rubber outer layer, which compresses to conform with the surface of the relatively incompressible yarns and presses the traveling sheet of yarns against the applicator surfaces leading to and away from the slot to prevent escape of foam and to prevent passage of foam between yarns to maintain uniform distribution of foam applied to the traveling sheet of yarns.

Processes and apparatus for dyeing a textile product are provided whereby an undyed textile product is introduced into a substantially anaerobic dyeing chamber having an oxygen content of less than 1000 ppm oxygen therein, and at least two dye mixtures having a differential dye exhaustion rate of at least 10% are applied onto the textile product within the substantially anaerobic dying chamber. Thereafter the dyed textile product may be exposed to an oxygen-containing atmosphere so as to oxidize the applied dyes. At least one of the dyes may have a dye exhaustion rate of at least about 25%, or even at least about 50%. The embodiments herein are especially adapted to dyeing of textile products whereby one dye in the at least two dye mixtures is a sulfur dye and another dye in the at least two dye mixtures is a leuco indigo dye.

Processes and apparatus are disclosed which substantially eliminate the formation of oxidized indigo dye before and during dye application onto a natural fiber yarn or fabric while allowing the leuco-indigo dye molecule to diffuse fully into the natural fibers of the yarn where it can fix to the fibers prior to oxidation (i.e., exposure of the leuco-dyed yarns to oxygen). Indigo dyed textile products (e.g., dyed cotton yarns that may be twill woven to form a denim fabric) exhibit exceptionally high colorfastness as determined by the AATCC Crock Test.