COLORS FOR RIGHT FIRST TIME DYEING
VS Dyes
VS Dyes
Salient Features
Chemifix VS Dyes
Chemifix 'VS' Dyes are based on B-Sulfatoethylsulfone reactive system. These dyes have low to medium substantivity/reactivity for cotton and therefore better recommended for padding and printing applications. However, the substantivity of majority of the dyes of this group is greatly enhanced after the addition of alkali, because of the generation of vinylsulphone form of dye from its precursor and therefore can be used for exhaust dyeing also.
Salient Features
- Suitable for exhaust dyeing at 60° C
- Possible to produce deepest shades
- Very much economical for medium and dark shades
- Excellent shade build-up
- Excellent solubility in water
- Excellent levelling characteristics
- Least sensitivity to variation in dyeing conditions
- Very good fastness to washing, rubbing and light
Check our Products list below :: Chemifix VS Dyes
for blacks at 8.0% shade
Key to Abbreviations: S = Suitable | LS = Less Suitable | NS = Not Suitable
Dischargeability: G = Good | F = Fair | P = Poor
1. Exhaust Dyeing Method (Winch/ Jet Dyeing)
(a) All-in-Process
In the method full amount of salt, soda and part of caustic soda are added to the bath in the begining and the fabric is run for 10 min. at room temperature. Then the pre-dissolved dye is added in two portions and the temperature is raised to the required level. Then the remaining amount of caustic soda is added and the dyeing is continued for 60-90 min.
(b) Normal Method
Start dyeing at room temperature with required amount of dye and run the machine for 10 min. Start raising the temperature to the required level @ 1-2° C min and simultaneously add the salt in two portions over a period of 15 min. After the required temperature is reached, alkali is added in two portions and dyeing is continued for 60-90 min.
Salt and Alkali requirement
| Dyeing Temperature | 60° C | 40° C | 30° C | ||
| Glauber's Salt / Common Salt (g/l) | 40-80 | 60-90 | 80-100 | ||
| Soda Ash(G/L) or Caustic Soda Solution | 20 | - | - | ||
| (70° Tw cc/l) < 2 % Shade | 1 | 2 | 5 | ||
| >4 % Shade | 2 | 3 | 8 | ||
| Soda Ash g/l | 5 | 5 | 5 | ||
Note:1
Turq. Blue G gives maximun color yield at 80° C. For Turq. Blue G 10-20 g/l Soda ash is uesd as alkali. Combination shades with Turq. Blue G are generally dyed at 80° C by proper selection of other components.
Note:2
It is preferable to use galuber's salt for blue R, T. blue G and T. Blue H2GP
1. Washing-off Treatment
After dyeing, to remove the unfixed/hydrolyzed dye, the following 'washing-off' sequence is recommended.
Cold rinse -------> Hot rinse -------> Neutralise (with acetic acid) -------> Soap (1-3 times) -------> Hot rinse -------> Cold rinse.
Soaping can be done with 1-2 g/l anionic or non-ionic detergent or polymeric washing off agent at boil for 15-20 min.
2. Pad-Batch Dyeing
Dissolve the required amount of dyestuff in hot water and cool the solution to room temperature and add urea (if required). Mix the dye solution with the alkali just before padding, preferably the dye solution and alkali are fed to the padding through a dye-alkali mixer. Pad the properly pre-treated fabric through the solution at 25-27° C and batch for 20-24 hrs. After fixation is completed, fabric is given washing-off treatment.
| Concentration of dye in pad-liquor | upto 20 g/l | 20 to 40 g/l |
| Urea (g/l) | 80 | 150 |
| Sodium Silicate (110° Tw) (Na 2O:Sio2 :: 1:2:1) (g/l) | 100 | 100 |
| Caustic Soda (Solid) (g/l) | 3 | 3 |
Notes
Orange 3R is not recommended above 15 g/l concentration, due to poor solubility / stability of dye in the presence of alkali.
3. Printing
(a) Print - Dry - Stream (Saturated) Method : Recipe
| Dye | X parts |
| Hot Water | 100-300 parts |
| Resist Salt | 10-20 parts |
| Sodium bicarbonate | 10-15 parts |
| Thickening | Balance |
| Total | 1000 parts |
Print -------> Dry -------> Saturated steam (7-10 min.) -------> Wash off
(b) Print - pad (alkali) - Cold dwell Method
Prepare print paste as per the above recipe without talking alkali. Print and dry the fabric. The pad the dried fabric through a solution containing 995-950 ml/lit. of sodium silicate (50° Be/ 104° Tw) and 5-50ml/lit. caustic soda (38° Be' / 71° Tw) and batch at room temperature for 20-24 hrs. After batching, the fabric is given usual washing-off treatment.
4. Discharge Printing
Majority of the Vinlysulfone dyes are suitable for white and colored discharge effects. Some of the dyes can be discharged to white with neutral or weakly alkaline discharge paste. General method is as below:
(a) Treat the dyed fabric first with small quantity of resist salt to protect the ground shade from reductive effect of printing paste.(b) Print the fabric with a paste prepared from the below mentioned recipe
| Rongalite C | 10-20 parts |
| Titanium Dioxide (1:1) | 10 parts |
| Discharge Salt W | 6 parts |
| Thickening agent | 40 parts |
| Caustic Soda 38 Be | 10-20 parts |
| Water | 4 parts |
| Total | 100 parts |
After printing, fabric is dried at about 80° C and then steamed for 10-15 min. in a star ager. After steaming fabric is rinsed in cold water and then with warm water. It is then soaped with non-ionic or anionic detergent at boil for 15-20 min.
( This information and our technical advice are given in good faith but without warranty. Our advice does not release you from the obligation to check its validity and to test our products as to their suitability for the intended processes and uses. The application, use and processing of our products and the products manufactured by you on the basis of our technical advise are beyond our control and therefore, entirely your own responsibility.)
