Disperse Dye

Product Information: By Product

1.Disperse Dye Introduction

Disperse Dye is the dye with smaller molecular and no water-soluble group in molecular structure. Textiles can be dyed only that disperse dyes are dispersed in dyes solution with the help of dispersants, which make disperse dyes dispersed well-proportioned. Disperse Dyes are mainly dyeing for polyester (it is a synthetic fiber which widely used in industrial applications because of its abrasion, stretch resistance, durability, chemical resistance and resilience. The most common polyester, polyethylene terephthalate(PET), is used extensively on all types of apparels including sportswear and hi-tech light-weight microfiber garments which provide improved breathability, water resistance, durability, and comfort. As for home furnishings such as carpet, drapes, upholstery, and pillow fiber-fill, they are large consumers of polyester fiber and fabric), acetate including secondary acetate and triacetate (acetate is primarily used for dresses, blouses, and special occasion apparels in addition to home fashion materials. Acetate offers a luxurious look with a soft hand and exceptional drape characteristics.), nylon (it is a synthetic fiber widely used in industrial applications because of its abrasion resistance, durability, high stretch ability, and resilience. They are also used extensively in sportswear and hi-tech light-weight microfiber garments which provide improved breathability, water resistance, durability, and comfort. Other nylon end-products include rope & cordage, parachute fabric, sail cloth, and cargo straps.), as well as polyamide, seldom for polyacrylonitrile. Fabrics dyed by disperse dyes are bright colors, good washing fastness, hence they have multiple applications. Due to insoluble in water, disperse dyes cannot dye for natural fibers such as cotton, hemp, fur and silk.

Particle size of disperse dyes must be about one micron in order to make the dye dispersed to be homogeneous and stable colloidal suspension in water promptly during processing, dispersants and wetting agents are added when grinding, there are lots of auxiliaries for after treatment, such as lignin, MF, anti-settling agent, anti-dusting agent, dispersants NNO, anhydrous sodium sulfate is applicable when strength is needed to adjust.

Disperse Dyes are classified as E-type, SE-type and S-type by the heat resistance during processing. E-type is bad sublimation fastness but good level-dyeing properties, suitable for exhaustion dyeing. S-type is good sublimation fastness but bad level-dyeing properties, suitable for thermosol dyeing. SE-type is between S type and E type.

Due to strong hydrophobicity, high crystallization and array, little fiber gap, not easy wetting and swelling, polyester fiber is hard to be dyed after the single dye molecules go into fiber by the regular methods. Hence special treatments have to be taken, such as carrier method, HTHP method, high temperature hot melt method. These methods make fiber gap increased by different conditions which can let fiber swelled, in the same time, auxiliaries are added to improve dyes' diffusion rate, it can make dye molecules diffusing into swelled and increased fiber gap.

2. Dyeing Process of Polyester and its Blends

Loading → Desizing & Scouring → Drying → Presetting → Weight → Weight Reduced → Dyeing or Printing → Heat Setting → Finishing

1) Desizing & Scouring: The aim is to remove spinning oil, desizer in fabrics and impurities such as stained oil contamination during spinning process.
Recipe and Formula: Detergent: 0.25g/l, Soda Ash: 2g/l, Caustic Soda (33° Be’): 2g/l, Sodium Hydrosulfite: 1g/l, Liquor Ratio: 1:10, under 80°C for 20min.
2) Presetting: The goal is to keep fabrics’ measurement stability and soft handling, which has a positive affect for dyeing, it is the key procedure to judge polyesters’ style. Recipe: Under 180-210°C for 30-45 seconds and over feeding around 10%.
3) Weight Reduced (Optical): When fiber molecular of fabrics under high temperature and concentrated alkaline is hydrolyzed, which makes polyesters’ less weight, performance changing, gap occurred in fabrics’ crossing point, hence the friction resistance of yarns drifting is reduced, it is to make textiles soft, smooth, elastic, as well as improve moisture and sweat absorption. After Weight reduced, fabrics should be washed abundantly and fix the PH value of polyester surface to be around 7, avoid the bad affects for processing afterwards.
Recipe:
4) Dyeing: High Temperature High Pressure (HTHP) Dyeing Formula: Epsilon Disperse Dye, Metal Iron Chelate Complex: 0.3-0.5g/l (according to water quality, it may not be added for soft water), High Temperature Dispersant: 1-2g/l (such as MF etc.), High temperature Leveler: 0.1-0.5g/l, Acetic Acid or Sodium Acetate Buffer: adjust PH value to be 4.5-5.5. Disperse Dyes should be mixed with H/T Dispersants, then they are pulping with water under 40-50°C and stirring well-proportioned to make them dissolved and filtered into dyeing machine.

Reduction Clearing formula: 100% Caustic Soda: 1-2g/l, Sodium Hydrosulfite 85%: 2-4g/l, Detergent: 1-2g/l
5) Thermosol Dyeing: It is continuous dyeing, mainly dyeing for polyester or cotton, the formula is: Padding-Drying: Epsilon Disperse Dye, Anti-migration agent: 1-5g/l, Wetting Agent: 1-2g/l, Buffer solution: with PH 5-6, temperature: 20-40°C, pickup: 60-70%, drying: under 70-90°C Thermosol Dyeing: Temperature: 180-220°C, time: 60-120sec. After Treatment: Washing by water, Reduction Clearing, Washing and Drying.

3. Dyeing Process of Direct Printing

Loading → Direct Printing → Drying → Fixation → Washing → Soaping → Reduction Clearing (Optical) → Hydro-extraction and Drying. Formula: Epsilon Disperse Dyes, 30°C Warm Water, Ammonium Sulphate: 2-5g, Sodium Hexametaphosphate: 0.5-1.0g, Thickener: 500-800g Color Fixing: The printed fabrics should be dried at temperature less than 120°C to avoid disperse dye penetration, HTHPS (Pressurized Fixation), HTS (High Temperature Fixation) or Thermosol method can be taken to fix colors after drying.

4.Discharge Printing

Polyester Dyeing → Washing (Reduction Clearing, optical) → Drying → Discharge Printing → Drying → HTS or PS → Washing → Finishing Formula: Stannous Chloride: 60-80g/l, Citric Acid: 30g/l, Urea: 50g/l, Guar Gum: 400g/l

5. Equivalents to DyStar, Huntsman, CIBA products

Epsilon offers equivalents to DyStar, Huntsman, CIBA brands products, the products include brands of DIANIX series, TERASIL series, REALAN series, LANASOL series, LANZOL series, REMAZOL series, CIBACARON series, PROCION series, ASTRAZON series, NOVACRON series, . Epsilon also offers OEM services and products.