A dye discharge composition exhibiting extended shelf life and/or pot life and high suitability for inkjet printing on dyed substrates, is disclosed. The composition comprises a reducing agent such as, for example, a sulfur-based reducing agent, and a chelating agent, such as a sodium salt of a polyamino carboxylic acid chelating agent. Use of the dye discharge composition in combination with a translucent colored composition and an optional opaque underbase composition, for forming an image on a dyed substrate is also disclosed. Processes for inkjet printing of an image on a dyed surface using the dye discharge composition, kits for use in such processes or an ink formulation containing same are also disclosed.

Provided is a pretreatment agent for ink jet textile printing that can provide printed matters on fabric with high color-developing properties and less bleeding. The pretreatment agent includes at least water and (A) a multivalent metal ion and polymer fine particles, (B) a cationic polymer and polymer fine particles, or (C) cationic polymer fine particles.

A decolorization method of a polyester fabric includes: providing a polyester fabric, in which the polyester fabric is a dyed polyester fabric and the polyester fabric is adhered with a dye and has a first L value; providing a first decolorizing solution and a second decolorizing solution, in which the first decolorizing solution contains a reductant and the second decolorizing solution contains an oxidant; and performing a decolorization process which includes: using one of the first decolorizing solution and the second decolorizing solution to decolorize one portion of the dye and using another one of the first decolorizing solution and the second decolorizing solution to decolorize another portion of the dye, so that a color of the dye is removed and the polyester fabric is white in color and has a second L value that is greater than the first L value.

The invention relates to a colorant composition for coloring fibers and fabrics comprising leucoindigo and at least one organic solvent. To achieve a stable composition, which is broadly applicable to different fibers and fabrics, the water content of the composition is less or equal to 10 wt.-% of the total weight of the composition or the water content of the composition is less or equal to 60 wt.-% of the total weight of the composition and the composition also includes a base.