Direct dyes offered by us are anionic dyes that come with substantively for cellulosic fibres. These are normally applied from aqueous dye bath that contain an Electrolyte, either:
Sodium chloride (NaCl)
Sodium sulfate (Na2SO4)
With the dyeing process with direct dyes being very simple, the dyeing is carried out in neutral/slight alkaline dye bath at/near boiling point. But, here a separate after treatment like cationic dye fixing that helps in enhancing wet fastness is also required for most direct dyeing processes. Being salts of complex sulfonic acids, chemically more than 75% of all direct dyes are un-metalized Azo structures with a great majority being:
Disazo type
Polyazo type
With ionic nature being anionic and soluble in water, these have affinity for wide variety of fibers like:
Cotton
Viscose
Silk
Jute
Linen
Further, these are also used as pH indicators and as biological stains. As these do not make any permanent chemical bond with cellulosic fibers, here, these are attached to it using:
Week hydrogen bonding
Vander waals forces
The flat shape and length of these dyes also enable them to:
Lie along-side cellulose fibers
Maximize Van-der-Waals, dipole and hydrogen bonding
Solving wash fastness issue for Direct Dyes: The quality of wash fastness is poor unless it is treated with suitable:
Dye fixing agent
Fastness improving finishing agent
For overcoming this, a special after treatment process is used. Under this process, a cationic bulking agent ‘RETAYNE’ is used where this agent glues dyes into fibers.
Major types of Direct Dyes:
Anionic Direct Dyes: These are used for:
Coloring papers
Controlling tint and shade
Correction of two sided paper color
Structural features: The main structural features of Anionic Direct Dyes are:
Planar vary from each other
Structural single & double bonds are much extended
Containing one/more than one sulfonate groups that make them soluble in the water
Cationic Direct Dyes: The main structural features of cationic direct dyes are:
We are also one of the leading names in the field of Optical brighteners which are also known as optical brightening agents. These have in them capacity to absorb light in violet/ultraviolet region of electromagnetic spectrum ad subsequently re-emit light in blue region. With the coloring matter, be it natural/present as contaminant in fiber being generally decolorized by different bleaching methods, the appearance of textile substrate is creamish after bleaching. Thus it is necessary that chemical treatment is done to neutralize yellow tint of textile fibers.
The usage areas of Optical brightening agents (OBA) include but are not limited to:
Textiles
Paper
Detergents
Plastics
Arriving at optical brightening effect: Optical brightening effect is gained by addition of light (meaning amount of light reflected by Fluorescent Whitening Agents absorbing high energy radiation in ultraviolet/violet region (330nm-380nm) on part of characteristic molecules and in turn emitting lower energy radiation in blue region). The same is visible through spectrum (400nm-450nm) and yields yellow appearance.
Characteristics:
These are effective only when incident light has significance proportion (like daylight) of UV rays
When material treated with OBAs is exposed to UV black light source, it glows in dark
Anionic OBA’s exhaust on cotton, wool and silk
Cationic OBA’s exhaust on acrylic and certain polyesters
Non-ionic OBA’s exhaust on all synthetics
Application of Optical Brighteners: Optical brighteners are widely used in:
Food coloring dyes are also called color additives and acts as pigment/substance that imparts color when added to food or drink. These are made available in variety of forms comprising :
Liquids
Powders
Gels
Pastes
Food coloring is used in commercial food as well as in domestic cooking. Further, it also finds usage in a variety of non-food applications like :
Cosmetics
Pharmaceuticals
Home craft projects
Medical devices
Why Food Colors : Colors are associated with certain flavors, where colors of food influence perceived flavor in products like candy, wine and others. The food color also simulate color perceived by consumers and are used as additives in foods for many reasons including:
Color loss due to exposure to light, air, extreme temperatures
Moisture and adverse storage conditions
These help in achieving :
Correct natural variations in color
Enhancing colors that occur naturally
Providing color to colorless foods
Water soluble synthetic dyes : These are permitted for application in food industry as well as in pharmaceutical and personal care applications. Some of the available forms of these dyes include:
Powder
Granular
Sphero clean
Plating Grade
As one of the leading names in offering Water Soluble Dyes for food industry, we ensure these are made available in:
High purity levels
Range of particle sizes
Blending infinite spectrum of powder shades
Lake Pigments : These Lake Pigments find application where dyes are unsuitable because of their solubility in water. Some common applications are:
Coating and icing where colour must not bleed
In baked treats where colour migration is an issue
These Lake Pigments are available in two main forms:
Powder: Ideal for any dry applications where a small use of lake imparts bright colour in dry mix
Pre-dispersed liquid (Dispersions): We disperse lake pigments in different liquids including water, oil, glycerin, sugar syrup, propylene glycol and others based on customers applications
Our products provide customers with following advantages:
