Shilpa Chem

Reactive Dyes

Reactive dye is a class of highly coloured organic substances, primarily utilised for tinting textiles, that attach themselves to their substrates by a chemical reaction that forms a covalent bond between the molecule of dye and that of the fibre. The dyestuff thus becomes a part of the fibre and is much less likely to be removed by washing than are dyestuffs that adhere by adsorption.

The very first fibre-reactive dyes were designed for cellulose fibres, and are still used mostly in this way. There are also commercially available fibre-reactive dyes for protein and polyamide fibres. In theory, fibre-reactive dyes have been developed for other fibres, but these are not yet practical commercially. The dyes contain a reactive group that, when applied to a fibre in a weakly alkaline dyebath, form a chemical bond with the fibre. Reactive dyes can also be used to dye wool and nylon, in the latter case they are applied under weakly acidic conditions.

The most important characteristic of reactive dyes is the formation of covalent bonds with the substrate to be coloRed, i.e. the dye forms a chemical bond with cellulose, which is the main component of cotton fibers.

Fiber reactive dye is the most permanent of all dye types. Unlike other dyes, it actually forms a covalent bond with the cellulose or protein molecule. Once the bond is formed, what you have is one molecule, as the dye molecule has become an actual part of the cellulose fiber molecule. No wonder you can safely wash a garment that has been dyed in bright fiber reactive colors with white clothing, a hundred times, without endangering the whites in the least – even if it is all different bright colors, or even solid Black! In contrast to all other dyes the reactive dyes bind chemically to the textile fibres, significantly improving the product’s colour stability and washability. Thus reactive dying of cotton is currently the most widespread textile dying process in the world.

We ‘SHILPA CHEM’ engaged in manufacturing of dyestuffs since last one decade. Reactives Dyestuffs are one of series apart from the direct Acid & Acralic range of Dyestuffs.

‘SHILPA CHEM’ presents the textile Dyers & Printers with a very wide range of reactive Dyes, which are suitable to various dyeing & printing of cellulose fibre.

SC ‘M’ DYES :

These are called ‘COLD BRAND DYES’ These dyes are having very good reactivity fastness properties. These dyes require milder alkaline contitions for applications & fixation at the optimum temperature of 25-35 Deg. C.

SC ‘H’ DYES :

These are named as ‘HOT NRAMD DYES’ These dyes are applied under strong alkaline conditions at high temperature of application compaRed to ‘M’ Dyes. These Dyes contains very good fastness properties to wash, perspiration, light etc. These dyes are suitable particularly for printing cotton, viscose, cuprammonium raysons & natural silk.

SC ‘HE’ :

These are bifunctional Reactive Dyes. Which are having two reactive molties of the same type viz Monochloro Triazinyl. The chromogen of the colour is supported through a stillbene in the molecule. This structure provides good light fastness and as well good washing fastness because of having high molecular weight. SC ‘HE’ Dyes give good yields irrespective the M:L ratio and having high substantivity. These are having high fixation and tinctorial value. All shades of SC ‘HE’ are mutually compatable in combination with good shade reproducibility. The optimum fixation temperature of SC ‘HE’ Dyes is 80-85 Deg. C.

SC ‘ME’ :

The optimum fixation temperature of HE type dyes is 80-85 C. We in SHILPA CHEM introduced a new range of Bifunctional Reactive SC ‘ME’ Dyes for our customers who are too conscious of energy consumption. In SC ‘ME’ Dyes one molecule is fused with two Reactive Group Vinyl Sulphone as well as Monochloro Triazine. The requiRed fixation temperature of SC ‘ME’ Dyes is 60 C. These dyes have advantage of high exhaustion, high fixation, high alkali stability, very good leveling property, excellent all around fastness properties like light, washing, perspiration, rubbing chlorine peroxide bleach. These dyes gives exceptionally good results on various textile printing including on discharge printing except Reds which gives slight Yellow ship stain.

We can provide washable Tintin colours for various blending of the yarns.