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Vinyl sulfone dyes are reactive dyes comprising a vinyl sulfone group as reactive group (a fiber-bonding site of the reactive dye, "reactive hook"). Due to the relatively high reactivity of the vinyl sulfone group with water (residual moisture, air humidity), it is present in many commercial products in a protected form.
Vinyl sulfones are dienophiles. Subsequent to the cycloaddition to a vinyl sulfone, the phenylsulfonyl group can be removed by reduction with zinc. [7] Vinyl sulfones are Michael acceptors. [8] Vinyl sulfones add thiols, such as cysteine residues. [9] This same reactive nature is responsible for their major industrial use in vinyl sulfone dyes ...
In a reactive dye, a chromophore (an atom or group whose presence is responsible for the colour of a compound) contains a substituent that reacts with the substrate. Reactive dyes have good fastness properties owing to the covalent bonding that occurs during dyeing. Reactive dyeing is the most important method for coloring cellulose fibers.
Chemical resist dyeing is a modern textile printing method, commonly achieved using two different classes of fiber reactive dyes, one of which must be of the vinyl sulfone type. A chemical-resisting agent is combined with dye Type A, and printed using the screenprint method and allowed to dry. A second dye, Type B, is then printed overtop.
Vinyl sulfone dyes have emerged as the predominant choice for discharge printing, largely owing to their distinctive chemical composition. Notably, the vinyl sulfone group undergoes breaking of bonds under the influence of reducing agents.
FD&C Red No. 40, more commonly known as red 40, is making headlines again as lawmakers debate whether food dyes should remain legal in the United States. The dye, which has been registered with ...
Vinylsulfonic acid is produced industrially by the alkaline hydrolysis of carbyl sulfate with subsequent acidification of the resulting vinyl sulfonate salt: [6]. The reaction is highly exothermic (reaction enthalpy: 1,675 kJ/kg) and requires exact maintenance of temperature and pH during the hydrolysis.
Reactive dye printing is a method of printing fabrics using reactive dye incorporated into a paste or wax including components such as sodium alginate gum, soda ash, urea and kerosin. Typically, the dye is dried at 130 degrees and cured at 180 degrees to permanently bond it, and the fabric later treated with a softener for better hand feel.