Pacific school of engineering Field : Chemical Subject : Organic Chemistry & Unit Process Code : Topic : Dye & pigment Guided by : Prof. Dr. H. s. Tailor sir, Prof. Dr. Himanshu sir.

Presented by : Sr.no.Enrollment no.Name Bhuva Vimal Borad Khushal Dhanani Chirag Karad Vivek Kathiriya Manish Kikani Dhruv

Dye for Cellulosic Fibres: Direct Dyes Azoic Dyes Reactive Dyes Sulphur dyes Vat Dyes

DIRECT DYES Direct dyes for Cotton, Viscose, Silk & Nylon Easy to dye - require only cooking salt & very hot to boiling water. Dyes have a good light fastness but only moderate wash fastness. It is possible to improve on wash fastness by after-treatment of dyed article with dye-fixing agent. These dyes are principally used for “not so expansive” products or product with fewer washes such as T-shirts, curtains & theatre productions.

Azo Dye Synthesis Blue component can be coupled with yellow or green component to form two different dyestuffs. AZOIC DYES The word 'Azoic' is the distinguishing name given to insoluble azo dyes that are not applied directly as dyes, but are actually produced within the fiber itself. This is done with impregnating the fiber with one component of the dye, followed by treatment in another component, thus forming the dye within the fiber.

AZOIC DYES The formation of this insoluble dye within the fabric makes it very fast to washing. The deposition of the dye on the surface of the fibre produces poor rub fastness, but once the loose dye is removed by boiling the fabric in soap, the dyeing becomes one of the fastest available. cold Normally it is dyed in cold for all natural fibers Naphtol dyes are not sold in the form of a "finished dye" but in form of their components (Insoluble azo base & fast color coupling compound) which combine on the fiber to produce a water insoluble azo dye of exceptional fastness properties.

SULPHUR DYES The first Sulphur dye was discovered in France in 1873, & further work done by Raymond Videl enabled the manufacture of 'Videl black". Its outstanding fastness to light, washing & boiling far surpassed any cotton black known at that time. The general disadvantage of the Sulphur dyes that they produce dull shades & lack a red. The main advantage lays in their cheapness, ease of application & good wash-fastness. In their normal state, Sulphur dyes are insoluble in water but are readily soluble in the solution of Sodium Sulphide. In this form they have high affinity to the all cellulose fibres.

SULPHUR DYES - USE: The use of Sulphur dyes is restricted to dull brown, Khaki & Navy shades, where a good wash but not boil-fastness is required. Most Khaki & Navy overalls are dyed with Sulphur dyes.

ACID DYES These dyes comprise a large number of dyes used for the dyeing of wool, silk & nylon. They vary considerably in their basic chemical structure, but have one common feature - they dye from an acid dye bath. All acid dyes can be grouped in 3 sub groups: a. Level dyeing acid dyes b. Acid milling dyes c. Pre-metalized dyes

ACID DYES A. Level dyeing acid dyes : These dyes produce bright dyeing. The main feature is their good leveling properties. They are dyed from a dye bath containing strong acids (Sulphuric or Formic acid). These dyes exhibit low wash & light fastness. B. Acid milling dyes :

ACID DYES B. Acid milling dyes : Selected because of their high & light fastness & are extensively used for dyeing woolen fabrics that are subsequently milled. These dyes require great care in application because uneven dyeings are difficult or impossible to rectify. The dye bath requires the presence of weak acid (acetic acid) or acid releasing salts (ammonium sulphate or ammonium acetate) from which acid is liberated during dyeing. C. Pre-metalized dyes :

ACID DYES & USE C. Pre-metalized dyes : These dyes represent an extension of mordant dyes. The metal component being already incorporated in the dye during manufacturing process. Very good light fastness even in pale shades  The family of acid dyes is very large & diverse, varying widely in their methods of dyeing, application & end use of the dyed fabric.  A choice of dyes should be made considering sometimes- incompatible factors: - level dyeing, fastness, brightness & ease of application.  Care must be taken to use the appropriate method as prescribed for a given dye. ACID DYES – USE:

Pigments Pigments consist of small particles of colored compounds. Are derived from finely ground naturally occurring minerals: rocks and ores.

Paints All paints have three types of components: Pigments Media Diluents

Application of Pigments Popular especially in printing. Advantages : easy to apply with good shade matching from lot to lot; full color range; & can be applied on all textile fibres & their blends.

Media, Diluents Media serves to suspend the pigments and bind them to the surface of the object painted. Examples are: beeswax, linseed oil, walnut oil, plaster, gumarabic and egg yolk. Diluents such as water, turpentine, or mineral spirits allow the painter to thin the paint to the best consistency for the work.

Ultramarine, Lapis Lazuli Ultramarine, from "across the sea", is the pigment from ground lapis lazuli, a semiprecious stone. Beautiful jewelry is made from lapis lazuli.

Malachite, Gemstone Makeup Malachite is also used for jewelry and pigment. Egyptian women put ground malachite mixed with water on their eyelids (as well as soot around their eyes).

Cinnabar, Vermilion Cinnabar Pigment Cinnabar is mercury sulfide and dangerous to inhale. It was used for pigment and jewelry. Cinnabar pigment applied to sculpture and to paper.

Verdigris Copper acetate ranging in color from green to blue. Made by treating copper sheets with the vapors of vinegar, wine, or urine and scraping the resultant corroded crust.

Burnt Sienna, Umbers Iron Oxide in clay Reddish Brown Burnt umber is a combination of iron oxide, oxide of manganese and clay, made by burning raw umber to drive off the liquid content. Burnt SiennaUmbers

Lead White Lead oxide Very opaque white Roman women used ground lead powder to make their faces look white. Roman women wore a face cream made from tin oxide.

Vine Black, Blue Pigments Carbon Recipes for blue pigments were mentioned extensively in medieval artists' manuals Vine Black Blue Pigments

Tyrian Purple, Carmine Alexander the Great destroyed the city of Tyre by filling its prosperous harbors with silt and killing or enslaving its inhabitants. A dyestuff precipitated on clay. Made from the ground female Coccus cacti, or cochineal, insect which lives on various cactus plants in Mexico and in Central and South America. Tyrian Purple Carmine