PIGMENT DYEING Name : MAZADUL HASAN SHESHIR ID: 2010000400008 Batch: 13th Batch (Session 2009-2013) Department: Wet Processing Technology Email: mazadulhasan@yahoo.com Blog: www. Textilelab.blogspot.com Southeast University Department of Textile Engineering PREPARED BY ©right PIGMENT DYE DEFINITION: Pigment is a substrate in a particulate form which is insoluble in water but which can be dispersed in this medium to modify its color and light scattering properties. They are organic or inorganic coloring materials. They have no affinity to textile materials. They are fixed on the textile material with the help of binding agent in form a thin invisible coating. In pigment auxochrome groups are absent. Pigment dyeing is not really "dyeing" in it's truest form because the pigments stick on the fabric with the help of binders Pigments are insoluble in water. They exist in the form of finely ground molecules, milled for garment dyeing purposes into a paste. When anionic dispersing agents are added, a slightly negative charge is present, thus the foundation for pigment dyeing is born. When a positively charged cationic pre-treat is added to the fiber a magnetic bond is formed. The process is complete when a cationic binder is added to "lock" the pigment into place.In pigment dyeing no actual chemical reaction takes place between the dye and the fabric. ClASSIFICATION OF PIGMENT: PIGMENT DYEING PROCESS: TRADE NAMES: Trade Names Manufacturer Country Wintramin Winsol chem- Industries India Helizerine BASF Germany Neopralac Francolor France Acramin Bayer AG West Germany PROPERTIES OF PIGMENT: 1. Insoluble in water. 2. Organic or inorganic compounds. 3. No auxochrome group. 4. No direct affinity towards textile materials. 5. Binder is required for fixation. 6. Applicable to all kinds of fibers or textile materials. 7. No after treatment is required after coloration process. 8. Rubbing fastness is poor. 9. Water, wash and light fastness is very good. 10.A wide range of bright shades can be produced for some physical properties- Particle size : 0.2-0.4 µ Specific gravity : 1.14-1.37 for most of the pigments Boiling points : Decompose at 190º- 345ºc Melting points : Softeners ranges from the points 110º-175ºc CHEMICAL PROPERTIES: 1. Most of the pigments are azoic compounds. Besides that it may be inorganic oxide, inorganic salt phthalocyanine metal compounds etc. 2. Insoluble in water and other solvents like white spirit, per chloroethylene, trichloroethylene, CCl4 etc. 3. Pigments are toxic. Some are oral toxic, some are dermal toxic, some causes eye irritation etc. REQUIRED PROPERTIES OF PIGMENTS: 1. Should have good covering power. 2. Should be chemically inert. 3. Should have freely mixing quality. 4. Should have good resistance to acid, alkali, bleaching agent etc. 5. Should have good fastness properties. 6. Should be applicable to all fibers and textile materials. 7. Should have well resistant to solvents. DIFFERENCE BETWEEN DYES AND PIGMENTS: DYES PIGMENTS 1. Water solubility is 70% 1. 100% water insoluble 2. Dyes have direct affinity to textile material 2. They have no direct affinity to textile materials 3. Auxochrome groups are present 3. Auxochrome groups are absent 4. Most of the dyes are organic 4. Most of dyes are inorganic 5. Costly 5. Cheap 6. No binding agent is required 6. Binding agent is required 7. Dye diffusions in the fabric 7. Pigment diffusions on the fabric [...]... Pigment dyeing The pigment dyeing process : PIGMENT DYEING FAULTS: 1 Listing effects: It occurs along the width of fabric due to uneven pressure of padder rollers which cause shade variation 2 Tailing effect: It occurs along the length of fabric due to changing concentration of pigment liquor This also causes shade variation ADVANTAGE OF PIGMENT DYEING: 1 A wide range of color can be produced by pigments... molecules of the Organic Pigments In the molecules of the Inorganic Pigments, the cat-ions of metal are found in an array form with the non-metallic anions This arrangement doesn't allow these pigments to dissolve in the solvent and plastic 4 have a high refractive index have much lower values 5 most inorganic pigments are opaque organic pigments are transparent COlORED PIGMENTS: At past- Yellow lead... insoluble azo- compounds (Group- I): CI pigment red: Red 3; Fire red: Red 4; Red tonner: Red 6; Per matone orange : Orange 5 b) Metal containing water soluble azo compounds: Low solubility (Group2a): Lithol red: Pigment red 49 Lake red: CI pigment red 56 4 High solubility (Group- 2b): Precipitation of pigment from orange 11: CI acid orange 7 EXAMPLE OF VARIOUS PIGMENTS: INORGANIC PIGMENT: I White pigment: ... of olifinic unsaturated monomers in an aqueous medium Monomers include: 5 Acrylic acid ester 6 Styrene 7 Acrylonitrile 8 Vinyl chloeid etc PIGMENT DYEING PROCESS: Dying Recipe: Pigment → 2 gm/ lit Binder → 20 gm/ lit Levelling agent → 1gm/ lit Temp (Padding) → Room to 60c PH → 4-5 Drying → 100c Curing → 14 0-1 80c for 2-3 min for cotton 16 0-1 80c for 2-3 min for synthetic M:L → 1:20 to 1:30 PIGMENT DYEING. .. the pigment is exhausted , the binder is fed into the dyeing machine and exhausted onto the fabric over a period of time Acetic acid is added to the bath, which facilitates binder polymerization, then the fabric is rinsed, the dyeing machine is drained, and the fabric is extracted Dyeing Curve: Application Principle : Pigment dyeing Application Principle : Pigment dyeing Application Principle : Pigment. .. PIGMENT: EXAMPLE OF VARIOUS PIGMENTS: 1 Dyes converted into pigment: a) Dyes made insoluble by precipitation on substrate: Peacok Blue Lake : CI pigment blue 24 ; Bronze red pigment : CI pigment 90 b) Vat dyes converted into pigment: Thio indigo red violet : Violet 36 Indanthrone blue : Blue 60 Perinone orange : orange 43 2 Quinacridone: Cinquasia blue B, Cinquasia red Y, Cinquasia violet R 3 Azo pigments:... in the batch or commercial dyeing machine After a period of time, the fabric is rinsed The pigment dyeing process is generally a three step process such as: 2 .Pigment exhaustion on the fabric The pigments are first mixed with water and a dispersing agent that imparts an anionic charge to the pigments This solution is added gradually to the dyeing machine The temperature of the bath is slowly increased... can be produced by pigments 2 Pigments can be applied to any kind of fiber It is the only coloration process of glass fiber 3 Pigments are cheap and available 4 No washing or rinsing is required after printing 5 Pigment dyeing process is speedy and fast 6 The curing and drying process is simple and easy 7 Water consumption is less DISADVANTAGES OF PIGMENT COLORATION: 1 Pigments are water insoluble... the fabric by a powerful cationic pretreatment Pigment dyeing is an electrical process whereby the goods to be dyed are given an electrical charge opposite that of the pigment When the pigment is added to the bath, the opposite electrical charges attract each other, much like the north and the south poles of two magnets Because of the electrical nature of the process A typical recipe for cationizing... silica 2 Colored pigment: Ultramine: China clay 30% + Sodium carbonate 32% +Sulphur 30% +Silica 4% +Rosin 4% 3 Cadmium Pigment: Color Prime Rose Yellow Orange Maroon components CdS, ZnS CdS Cds, 0.2 CdSe Red CdS, 0.4 CdSe CdS, 0.7 CdSe 4 Iron Oxide: i) - FeOOH of Fe2O3 H2O ii) FeSO4 H2O (Red, Brown, Black) iii) FeO, Fe2O3 and FeOOH (Mixed crystal) INORGANIC PIGMENT: REQUIREMENT OF WHITE PIGMENT: 1 Primary . properties- Particle size : 0. 2-0 .4 µ Specific gravity : 1.1 4-1 .37 for most of the pigments Boiling points : Decompose at 190 - 345ºc Melting points : Softeners ranges from the points 110 -1 75ºc . to "lock" the pigment into place.In pigment dyeing no actual chemical reaction takes place between the dye and the fabric. ClASSIFICATION OF PIGMENT: PIGMENT DYEING PROCESS: TRADE NAMES: Trade. fabric EXAMPLE OF VARIOUS PIGMENTS: ORGANIC PIGMENT: 1. Dyes converted into pigment: a) Dyes made insoluble by precipitation on substrate: Peacok Blue Lake : CI pigment blue 24 ; Bronze red pigment : CI pigment