Direct Dyes which specially used for paper can be closely inosculated with paper fabric, and can be dyed directly on paper fabric, so it can be widely applied to paper dyeing industry.
When dyeing paper with Direct Dyes, it should be first solved in 80-90 boiled water, then diluted and percolated, which is quite important in obtaining brilliant leveling effect.
For achieving best dyeing pattern, the order should be sorted between dyes and other additives as follows:
Dyes---Sizing MaterialAluminium Sulfate
Owing to great inosculation between Direct Dyes and Paper Fabric, which should be mixed evenly after adding dyes into paste to avoid uneven effect as well as color spot. Twenty minutes later, add into Aluminium Sulfate again for obtaining best leveling effect.
It is best to use both Direct Dyes and Basic Dyes to dye mixed paste, the order as dyeing should be sorted as follows:
Sizing MaterialDirect Dyes---Aluminium Sulfate---Basic Dyes