What is Dye

Dye is a natural/synthetic substance that finds application for adding a color/altering existing color shade. As a coloring material, dyes are used to color commodities of day to day use and can be applied everywhere including

• Plastic toys for children
• Fabrics worn
• From products like food
• Wood items

These are hardly any industries left where dyes are not used commercially. As a coloring substance, dye has an ionizing and aromatic organic compound that affinity to substrate to which it is being applied. Generally being applied in aqueous solution, it may need mordant to improve fastness of dye on fibers.

The support from dyes assists in :-

• Easily manipulating things according to our liking like at basic level, use color in identifying individual components of tissue sections
• Dyes are applied to substrates like textiles, plastic, paper, food
• These are also completely/partially soluble in which these are put to

Basically ionising & aromatic compounds, dyes have Chromophores present in them with their structures having Aryl rings that have de-localized electron systems. These structures are responsible for absorption of electromagnetic radiation that features varying wavelengths (as per the energy of electron clouds).

These Chromophores make dyes highly effective in their ability to absorb radiation. Further, Chromophores also act by making necessary energy changes in de-localized electron cloud of dye that invariably results in compound absorbing radiation within visible range of colors (not outside it).

Electrons may result in loss of color with their removal causing rest of electrons to revert to local orbits. A good example of this is Schiff's reagent; a sulphurous acid that reacts with Pararosaniline. This leads to Sulphonic group attaching itself to compound's central carbon atom which hampers conjugated double bond system of Quinoid ring. It causes electrons to become localized and as a result ring ceases to be Chromophore, thus rendering dye colorless.

The colors of dyes can be altered by use of modifiers. Here, Color modifiers of methyl/ethyl groups are responsible for any alteration in dyes.

Dyestuffs :-

• Reactive Dyes
• Acid Dyes
• Direct Dyes
• Basic Dyes
• Solvent Dyes

Inkjet Dyes :-

• Dyes for Water Based Inkjet Inks
• Dyes for Digital Textile Printing
• Pigments for Water Based Inkjet Inks

Dyes for Wax Printing :-

• Ribagen Dyes
• Ribabase Dyes
• Naphthols
• Salts
• Ribafix Dyes for Printing