Is direct dye water-soluble?
The direct dyes are mostly sodium salts of aromatic compounds. They are soluble in water and their solubility increases with temperature. The direct dyes can dissociate into anions in water.
Why are direct dyes soluble in water?
Direct Dyes (Anionic) Composition: The “direct dye” classification in the Color Index system refers to various planar, highly conjugated molecular structures that also contain one or more anionic sulfonate group. It is because of these sulfonate groups that the molecules are soluble in water.
What are water-soluble dyes?
Acid dyes are water-soluble anionic dyes that are applied to fibers such as silk, wool, nylon and modified acrylic fibers using neutral to acid dye baths.
What is CPC blue?
Copper phthalocyanine (CPC) blue is the copper (II) complex of tetra aza tetra benzoporphine (CPC) whereas phthalocyanine green is its chlorinated derivative. CPC Blue is an upstream product and is a raw material used for the manufacture of our Pigment Blue and Pigment Green products.
What is meant by direct dyes?
direct dye, also called Substantive Dye, any of a class of coloured, water-soluble compounds that have an affinity for fibre and are taken up directly, such as the benzidine derivatives. Direct dyes are usually cheap and easily applied, and they can yield bright colours.
Why direct dyes are called as direct dyes?
It is called direct dye because it can be directly applied to the textile material due to its higest substantivity towards fibre. Direct dye is also know as “salt colours ” because common salt or Glauber’s salt is used. it is also know as substantive dye. Direct dye is highly soluble in water.
What is a soluble color?
Water-soluble food colour obtained by. dissolving the powder in water, propylene. glycol or glycerine. This type of colouring is used for water-based food products. It is perfect for sugar work (during baking), macaroons, icing, cake and cream.
What are direct dyes used for?
Direct dyes are used on cellulosic fibers when good lightfastness is needed, but washfastness is not critical. This includes window coverings, upholstery, and heavy bedding where the finished item is seldom washed or is labeled as dryclean only.
How do I make my CPC blue?
Take above heated crude material into dumping vessel with spent sulphuric acid (mother liquor from Alpha Blue) and add water. Then start heating up to 95 deg C and maintain for 3 hrs.. Then filter in filter press, wash it , Neutralize it , dry & pulverize it and packed the final product as a CPC blue.
Is Phthalo blue the same as phthalocyanine blue?
Phthalo blue (or Phthalocyanine Blue BN) is an organic blue developed by chemists under the trade name “monastral blue”. The color was presented as a pigment in London in November 1935. They’re lightfast, and an ideal pure blue for it absorbs light almost completely except for the green and blue bands.
What is direct dyes in textile?
Direct dye: A class of dye that can be applied directly to cotton or other cellulosic fabrics such as rayon, silk, and wool. Direct dyes are applied in a neutral or alkaline bath of hot water. They do not require mordant or fixatives for fastness; instead, they attach with hydrogen bonds and van der Waals forces.