Acid dye application on wool

  Application of Acid dye on wool :

This is very easy to dye wool fiber with Acid dye. Due to easy dyeability in the acid dye, it is also known as a wool dye. The dye bath condition is strongly acidic to make it effective. Strong acids like hydrochloric acid, sulphuric acid, and Nitric acid can damage fiber so we can use fewer strong acids than these. We can use Phosphoric acid, Soda ash, and formic acid or acetic acid. In every dyeing process, we need to follow a recipe. This is also not out of that. So let's see the recipe.  

Recipe: 

Acid dyestuff: 2% based on the weight of the product

Acetic acid: 3% based on the weight of the fabric 

Dispersing agent: 0.3% based on the weight of the fabric 

Water: 20 times based on the weight of the fabric 

Temperature: 60°C -90°C

Time: 1 hour 

Sometimes we use 0.5%-1% sulphuric acid.

Dyeing process of acid dye wool fiber: 

First of all, we need to take dyestuff in a bath and there add dispersing agent as much necessary quantity. Then need to add acetic acid and need to mix it up well and make dissolve. In another dye bath need to take water as per the recipe and need to add dye solution and make ready-to-dye fabric. After that, we add fabric to the dye bath and raise the temperature from 80°C to 90°C and treat for up to 15 minutes. After dyeing completing need to unload the fabric and wash it off with normal water. 

Aftertreatment process: After the dye needs after treatment the fabric to fix dye and remove unfix dyes. First, we need to use tannic acid 1-2% and 1-2% formic acid (85% conc.) under the condition of a temperature of 70°C, and the time will be 15-20 minutes. After this process needs to use 1-2% Tarter Emetic and treat for 15-20 minutes and complete the process.  

During the use of neutral acid, dye dyestuff will be 2%, Ammonium sulphate 3-4%, TR oil 0.1%-0.2%, Water will be 40 times than product weight, temperature 80-100°C and time will be 45-60 minutes. 

Effect of acids on acid dyestuff: 

During dyeing with acid dye if we use acids they are very helpful to absorb dyes into the fabric. Also, there is some dye that has no absorbency without an acid bath. In the case of protein, fiber has excellent absorbency in acid dye. As the acid dye is made of acid so to dye protein fiber must need to use the acid bath. Otherwise, if we use metallic dyebath then it can destroy the dye reaction ability. For this reason, to do acid dye needs acid dyebath. 

Some commercial name of acid dye is given below: 

Lurasol → BASF company →Germany 

Kitone→Cibageigy→ Switzerland

Sandofast→ICI →UK

Supracen → Bayer →Germany