One-Bath Two-Stages Dyeing of PC Blend With Disperse-Reactive Dye

Last updated on July 30th, 2023 at 11:39 pm

Usually, this method is used for dyeing of knit fabric and yarn in winch, Jet, beam or package dyeing machine. In this method, the polyester part is dyed first with disperse dyes and then dye the cotton part with bi-multi-functional type reactive dyes in the 2^nd stage.

Table of Contents

Typical Recipe for Polyester Part

Dispersing agent = 0.5 – 1.0 g/l

Sequestering agent = 1.0 – 2.0 g/l

Levelling agent = 1.0 – 2.0 g/l

Buffer solution = 0.5 – 1.0 g/l (To maintain p^H4-5)

Disperse dyes = x%

Temperature = 130-135⁰C

Time = 30 – 60 min

M : L = 1 : 5 – 1 : 10

Preparation of Disperse Dye Solution

Disperse dyes are water insoluble thus need to make a dispersible (partially soluble) solution by stirring with warm water. If necessary, add dispersing agent with it and stir rapidly.

Typical Recipe for Cotton Part

Wetting agent = 0.5 – 1.0 g/l

Reactive dye = x%

Salt = 4 g/l

Soda = z g/l

Temperature = 50 -60⁰C

M : L = 1 : 7

P^H = 10 – 11

Working Procedure

Set the dye bath with substrate at 50⁰ C temperatures and add dispersing, leveling, buffer (p^H around 4-5) and other auxiliaries, then run the dye bath for 5 – 10 min. Add (By dosing) dye solution of disperse dyes and raise the temperature to 80⁰C by 3⁰/min. Raise the temperature from 80⁰C to 130⁰C by 1.5⁰C/min.

Run the bath for 30-60 min at the same temperature. Lower down the bath temperature 80-90⁰C over 10-20 min and add alkalis (e.g. tri-sodium phosphate) for neutralization (to drop the p^H around 7).

Add (By dosing) reactive dyes with salt accordingly to recipe and run for 20-30 min. lower down the temperature to 60⁰C and add alkalis (soda ash) and run for 30 – 60 min. Drop the dye bath and carry on the after treatment process.