Thursday, 11 June 2009
Common Causes of Dyeing Defects
Common Causes of Dyeing Defects:
It is important that the general precautions should be followed while dyeing a textile material. It is always helpful to keep a record of all the conditions (including temperature, time, conc of color, chemicals, material to liquor ratio) in order to get an even shade in each batch. In general the following are the common causes of dyeing defects across all the categories of dyes:
1. The material is not well prepared for dyeing and printing
a. Material having dead fibres or other defective fibres
b. Left over of Chemicals after bleaching etc.
c. Material not properly desized
d. Material not properly mercerised.
e. Absorbancy of the fabric not proper
f. Sticking of insoluble material on the fibres
g. Impurities are not removed properly
h. Uneven heat treatment.
2.Water Quality not Proper
a. More Hardness of water
b. Water has metal ions such as iron.
c. pH of water not proper
d. Water having more chlorine
3. Due to Shortcomings in making Dyeing Solution
a. Improper weight ratio of colors, material and chemicals.
b. Improper material to water ratio
3. Improper filtering of concentrated colors.
4. Due to Shortcomings in the dye machinery
a. Coming out of Dye liquor during dyeing
b. Defective instruments controlling temperature, pressure speed etc.