'Standardization of Recipe forDyeing Staining Free Polyester/Cotton Blended Yarns'


1)      Abstract:


Disperse dyes give excellent overall fastness properties with polyester where it gives very poor fastness properties with cellulose. Thereason behind this is disperse dyes does not have any substantivity &affinity towards cotton & cotton cannot be dyed at very high temperature aslike Polyester. Hence P/C blend dyeing will not give sufficient fastness properties compared to 100% Polyester. Normally in industries a recipe used for dyeing 100% Polyesteris also applied for different proportions of P/C blends and then it is toppedup with reactive dyes to match the shade. But it will not give sufficient fastness properties.


The object of the work is to standardize (P/C blend workedout with three different proportions) and to formalize the individual recipefor each proportions to improve the fastness properties of blended fabrics.


2)      Introduction:


100% PET means for strength, crease resistance but it cannotbe wearable because of low moisture content, static generation andaccumulation, so P/C blend enters in market because it has a advantages of bothPET and cellulose and can be wearable.

PET cotton blend has got lot of advantages from user pointof view but from dyers point of view it was difficult to dye the blends. P/Cblends does not give sufficient fastness properties as like 100% PET withdisperse dyes. In industries, single recipe used for 100% PET is also appliedfor different proportions of P/C blends & then it was topped up withreactive dyes to match the standard shade. But the fastness properties of these blend is a big question mark. While using disperse dyes for dyeing P/Cblends, it is noticed that the PET portion is not only dyed but not thecellulosic portion. It only stains the cellulosic portion. So the overallfastness properties of P/C blend fabrics is going to be less and also thestaining of disperse dyes on cotton is more.

In our work, we are going to dye three different proportions of P/C blends with disperse dyes and reactive dyes. Here, we change the procedure of dyeing P/C blend which are in practice in order to standardize the individualrecipe for each proportion by using disperse dyes and reactive dyes.


3)      Materials& Methods:


In our work, we have taken p/c blends yarns since p/cblended fabrics are mostly used for wearable purpose

3.1 Material:


1. 100% polyester yarn


Type : spun yarn

Count : 20s


2.



 

3.2 Dyes Used:


Dyes Manufacturer: CIBA


Disperse dyes:


  1. Dark red 2B
  2. Scarlet RR


Reactive Dyes:


  1. Red F3B
  2. Yellow MERL
  3. Blue BBID


3.3 Chemical and Auxiliaries


  1. Acidic Acid
  2. Ammonium Sulphate
  3. Soda
  4. Salt
  5. Anionic Soap


Acidic Acid:


Manufacturer    - Parrys India (p) Ltd.,

Concentration   - 100%

Purity              - 99%


Ammonium Sulphate:


Manufacturer   - Parrys India (p) Ltd.,

Concentration  - 100%

Purity             - 95%


Soda


Manufacturer    - TATA Chemical (p) Ltd.,

Concentration   - 100%

Purity              - 95%


Salt


Manufacturer    - TATA Chemical (p) Ltd.,

Concentration   - 100%

Purity              - 95%


3.3. Methods


The grey polyester cotton blend yarn is followed with following recipe and it is neutralized with Acetic Acid at room temperature.


H202                             - 2 gpl

Na2CO3                      - 2 gpl

Wetting Agent        - 1 gpl

Temperature / Time - Boiling Temp / 30 min.


Then the work is made with different recipe as follows. The polyester cotton yarn of different blend is dyed with the same amount of disperse dyes as follows:


 

100% polyester

Dark Red 2B             - 1.8 %

Scarlet RR                - 0.93%

Ammonium Sulphate - 3g

Acetic acid - 0.3%

Polyester / Cotton blend - 52 / 48

Dark Red 2B             - 1.8 %

Scarlet RR                - 0.93%

Ammonium Sulphate - 3g

Acetic acid               - 0.3%

Polyester/cotton blend 65 / 35

Dark Red 2B             - 1.8 %

Scarlet RR                - 0.93%

Ammonium Sulphate - 3g

Acetic acid               - 0.3%

Anionic Soap

Manufacturer             - Clariant Chemicals (p) Ltd.,

Concentration            - 100 %

Purity                       - 100 %


4) Dyeing Procedure


The dye bath is set with


1g/liter                      - Dispersing agent

0.5 g/liter                  - Wetting agent / leveling agent (optional)


The redox buffer is added and the pH is adjusted to 5.5. The liquor is circulated through the package at 50C for.15 min. The dyes are dispersed in 10 to 20 times in the weight of water at 45-50C. The dispersion is filtered through a thin cloth into the dye bath. The liquor is circulated and the temperature raised to l30oC in 30-min (The-pump pressure is slightly higher than the static pressure. (Dyeing is continued for 40-60 min). The dye-liquor is circulated inside-out throughout the whole dyeing cycle so that the position of the fabric is not disturbed. The flow of liquor may be from inside out for 10 min to outside-in for 10 min in every 10 min to get very uniform results. After about 40 min, a sample is taken out for the shade matching. The liquor is cooled to 80-90C and before shading disperse-dye liquor is added to avoid uneven dyeing. On completion of dyeing, the dye bath is drained at the highest possible temperature Otherwise the shade appears bronzy because of the deposited ash like oligomer powder that may dust off and create problems in finishing The precipitated dyes are difficult to remove from the PET surface and the lower the rubbing fastness of dyed goods. Thus, the bath must be dropped the dyeing temperature (or) as near to that temperature as possible. However, there are difficulties in dropping the bath (which is under pressure). Since, lot of steam is generated when the hot liquor comes to atmospheric pressure. Special arrangements are usually made to take care of this problem, and dropping in soaping of the material is washed, reduction-cleared, and soaped.


5) Recipe for Shade Matching:

The following recipes are used for topping up the polyester / cotton blend with reactive dyes to match the shade.


P/C blend P/C blend

(65 / 35) (52 / 48)


Red F3B                  - 3.4 %                 Red F3B            - 5%


Yellow M3RL           - 1.6%                  Yellow M3RL      - 1.6%


Blue BBID               - 0.1%                  Blue BBID          - 0.1%


Salt / Soda              - 14g / 3 g             Salt /Soda         - 14g /3 g


 

Dyeing Procedure:

The dye bath is setup with required amount of dyes at RT. After 10 min, required amount of salt is added. Raise the temperature to 600c. Dyeing is carried out for 20 min. Then soda ash of required quantity is added. Continue the dyeing for 90 min and then after treatment is given.


6) Standardized Recipe:

Here, the disperse dyes are standardized according to the proportion of the polyester portion in polyester / cotton blend.


100% polyester

Dark Red 2B              - 1.8 %

Scarlet RR                 - 0.93%

Ammonium Sulphate   - 3g

Acetic acid                 - 0.3%


P/C blend 65 / 35

Dark Red 2B              - 1.1 %

Scarlet RR                 - 0.5%

Ammonium Sulphate  - 3g

Acetic acid                - 0.3%

P/C blend 52 / 48

Dark Red 2B              - 0.9 %

Scarlet RR                 - 0.4%

Ammonium Sulphate  - 3g

Acetic acid                - 0.3%

Then it is taken for reduction clearing.


Reduction Clearing:

Caustic                     - 2 gpl

Hydrose                    - 2 gpl

Cyclone ECO            - 1 gpl

Temperature              - 800 C

Time                         - 15 min


7) Standardized Recipe for Cotton


The standardized recipe for cotton portion by using reactive dyes is given below followed by after treatment


P/C blend 65 / 35 P/C blend 52 / 48


Red F3B                   - 7.8 % Red F3B - 5.2%

Yellow M3RL             - 4.1% Yellow M3RL - 3.0%

Blue BBID                 - 2.4% Blue BBID - 1.6%

Salt - 16g Salt           - 16g

Soda - 5g Soda         - 5g


8) Results and Discussion


Based on the inference of our work the following results are obtained, which are tabulated below.


Table 8.1: Comparison of light fastness results of conventional dyed and standardized dyed samples


S.No.

Blends

Hours

Conventional Dyeing

Standardized Dyeing

1.

100 % PET

20

4-5

4-5

2.

65-35 P/C

20

4

4-5

3.

50-50 P/C

20

4

4-5


 

Table 8.2: Comparison of rubbing fastness results of conventional dyed and standardized dyed samples


S.No.

Blends

Conventional dyeing

Standardized dyeing

Dry

Wet

Dry

Wet

1.

100 % PET

4-5

4-5

4-5

4-5

2.

65-35 P/C

4

3-4

4-5

4-5

3.

50-50 P/C

4

3-4

4-5

4-5


Table 8.3: Comparison of sublimation fastness results of conventional dyed and standardized dyed samples

Conventional dyeing

100% p Yarn Red colour

P/C 65-35 Red colour

P/C 50-50 Red colour

Time (seconds)

120

120

120

Temperature (Deg.C)

120 + 2

120+2

120+2

Staining on wool

4-5

4

3-4

Acrylic

4-5

4

3-4

Polyester

4-5

4

4

Nylon

4-5

4

3-4

Cotton

4-5

4

3

Acetate

4-5

4

3-4


Standardized dyeing



100% p Yarn Red colour

P/C 65-35 Red colour

P/C 50-50 Red colour

Time (seconds)

120

120

120

Temperature (Deg.C)

120 + 2

120+2

120+2

Staining on wool

4-5

4-5

4-5

Acrylic

4-5

4-5

4-5

Polyester

4-5

4-5

4-5

Nylon

4-5

4-5

4-5

Cotton

4-5

4-5

4-5

Acetate

4-5

4-5

4-5


Table 8.4: Comparison of washing fastness results of conventional dyed and standardized dyed samples

S.No.

Blends

Conventional dyeing

Standardized dyeing

Change in shade

Staining on cotton

Change in shade

Staining on cotton

1.

100 % PET

4-5

4-5

4-5

4-5

2.

65-35 P/C

4-5

3-4

4-5

4-5

3.

50-50 P/C

4-5

3

4-5

4-5



Light, Rubbing, Sublimation and Wash Fastness are found to be excellent in the standardized method samples when compared to normal dyeing method.


 

9) Conclusion


Washing fastness, light fastness, sublimation and rubbing fastness of 100% PET are excellent in 100% polyester. Fastness properties like wash, light, rubbing and sublimation properties was reduced to10-15% compared to 100% Polyester . Disperse dyes stains on cellulose to a greater extent in P/C blends to that of 100% Polyester in Normal Method.

In Standardized Method, wash fastness, light fastness and all other fastness properties was proved to be excellent in 100% Polyester. Based on the above results, we conclude that by standardizing the recipe for each proportions, fastness properties of the fabric was increased and we can achieve stain free dyeing P/C blended yarns.

This work can be tried in all other classes in reactive dyes, since reactive dyes mostly have affinity and substantivity with cellulose. This work can be extended in other fibre blends like P/V, P/W.The work can be modified by varying the parameters like time, temperature and concentration. This project consumes more reactive dyes compared to normal method. This can be tailor made by selecting proper concentration. We work the material in two bath process. Other modes of application (i.e.,) one bath process, can also be tried.


10) References


1)    LS super fast dyeing, finishing and thermo migration - Ciba Dyes and Chemicals.

2)    Keshav V. Datye and Vaidya- "Chemical processing of synthetic fibres and blends" - pp. 183-190.

3)    A.Adwin Sunder M.Tech.- "Quality Assurance in Textile Wet Processing" - pp. 57-61 & 67-73.


About the Author:


M. Parthiban is a Lecturer in the Dept of Textile Technology (Fashion Technology), PSG College of Technology, Coimbatore.