They is dyed about cellulosic materials. The device is almost the same because described inside direct dyes.
Advantage: high wet fastness due with covalent bonding (Chemical Bonding) between materials plus dyes, conveniently dyed about materials.
Disadvantage: Expensive.
Dyeing Conditions:
A. Continuous Process:
1 Pad-dry-bake This really is easy way for cotton or cotton blends materials.
2 Pad-dry-Pad (Chemical)-Steam This will provide brighter plus more intense color than way 1.
B. Exhaustion Process:
Textile Auxiliaries:
1. Salt – lessen damaging charges found on the materials
2. Water – dyeing media.
3. Soda Ash – excite the dye with link with all the materials with covalent bonding. So, it improves wet fastness
4. Fixing Agent – improves wet fastness for thick shade however, commonly lessen light fastness.
Direct Dyes (Anionic):
They is dyed straight about cellulosic materials. Without the presence of salt, whenever the materials are immerged inside water, it can show anionic charge that repels the dyes. Adding salt into the dye shower, it may decrease anionic found on the materials thus the dyes may receive closer plus adsorb into the materials.
Advantage: cheap, conveniently dyed about materials
Disadvantage: bad wet fastness plus certain dyes have bad light fastness.
Textile Auxiliaries:
1. Salt – lessen damaging charges found on the materials
2. Water – dyeing media
3. Fixing Agent – enhance wet fastness yet normally lower light fastness
Dyeing Conditions:
(Exhaustion): dyeing lOOoC x 30-90 mm repairing 6OoC x 20 mm.
(Continuous) pad –> dry –> steam –> wash –> soap –> dry
Vat Dye (Anionic when soluble):
The dye is called within the container (Vat) which utilized for rotting the dye with alkali answer. This important procedure can minimize the dye from insoluble with soluble dye (right for fatigue inside the cellulosic fibers). Then the maker could synthesize man-made vat dye.
Dyeing Process:
1. Dissolve dye into water (insoluble dye)
2. Vatting task by reducing the insoluble dye inside alkali condition. (Soluble dye)
3. Absorb into materials (soluble dye)
4. After dyeing, oxidize the dye with oxidizing agent (insoluble dye)
5. Wash plus soap the goods
Dyeing Conditions:
A. Continuous Process:
1 Pad-dry-Pad (Chemical): The answer of the dye is prepared without adding reducing agent with guarantee leveling dyeing. After which, the goods are passed with chemical bathtub with minimize the dye into soluble dye plus fix in the goods. Oxidizing agent is put into the goods plus converted with insoluble dyes.
Textile Auxiliaries:
1. Salt – decrease the bad charges found on the materials
2. Sodium hydroxide – changes pH with the dyeing bathtub plus makes the right conditions for reducing agent.
3. Sodium hydrosulfite – reducing agent for the vat dyes.
4. Water – dyeing media
5. Oxidizing agents – (Hydrogen peroxide or Acetic acid or Air) oxidize the soluble with insoluble dye
(Sulfur Dye Anionic when soluble) :
The dyeing task has the same procedure because described inside the vat dye except which utilizing Sodium sulfide rather of Sodium hydrosulfide.
Dyes for Synthetic Fiber:
Disperse Dye
Dyeing Conditions:
1. Insoluble dye inside water
2. Less water soluble
3. Water insoluble inside polyester fibers
A. Exhaustion Process:
1 At boil with carrier, this task is right for acetate fiber plus pale shade polyester fiber dyeing. Carrier is an auxiliary for enlarged fiber inside purchase with enable more dyes absorbing inside. Then the utilization of carrier is reduced considering it can be a carcinogen.
2 At l3OoC without carrier with all the excellent temperature, the dyes is dissolved into small molecules as well as the void inside fiber structure is opened. This will provide thick shade.
B. Continuous Process Pad –> Pre-dry (100oC Thermo fixation (18OoC reduction clearing (RC)
Printing with Disperse Dyes:
Textile Auxiliaries:
1. Dispersing Agent – makes the dye answer stable plus disperses inside the dye bathtub.
2. Acid – adjust pH with the appropriate condition for the dye shower.
3. Carrier – swell the fiber plus dissolve the dye with result in the dye getting into fiber.
4. Leveling agent – create more leveling dyeing (several can have adverse impact on slower dyeing)
5. Water – dyeing media
Acid Dye (Anionic):
The dye is known as acid considering it demands acidic dyeing condition. It is dyed about protein materials (silk, wool, plus additional animal fibers) plus about polyamide materials. Acidic condition will provide the materials showing positive charge. As the bad charge might attach straight with positive charge, plus penetrate into the materials.
Dyeing conditions: l00oC x 30-60 mm
Textile Auxiliaries:
1. Leveling agent – for levelness dyeing.
2. Retarding agent – for inhibiting the dye not attach with materials too rapidly.
3. Acid – adjust the dyeing condition plus result in the materials with show positive charges.
4. Water – dyeing media.
Basic Dye (Cationic)
The dye shows positive charge. Usually, the dye is used about wool, silk plus poly-acrylonitrile (acrylic).
Dyeing Conditions:
l00oC x 30-60 mm Dyes Dyeing Condition (pH)
Acid (Wool) 2-4, 4-6, 6-8 (depends about kinds of dyes)
Acid (Nylon) four.5-5.5, about kinds of dyes)
Basic 3.5-4
Direct 7.0
Disperse (Polyester) 5-6
Disperse (Acetate) 6.5-7.0
Disperse (Triacetate) four.5-6.5
Reactive 7.0
Textile Auxiliaries:
1. Leveling agent – for levelness dyeing.
2. Retarding agent – for inhibiting the dye not attach with materials too rapidly.
3. Acid – adjust the dyeing condition plus result in the materials with show bad charges.
4. Water – dyeing media.
