How To Calculate Dyes Recipe in Polyester/Cotton Blended Fabric In Soft Flow
we dye any fabric in soft flow , first we develop the base fabric recipe in the lab , It is our basic practice to get shade as close as possible to the target shade. If all component of fabrics are of same blend as base fabric , in that case it is very easy to decide the Bulk dyeing recipe , we can just copy the lab recipe . But in case base fabric has different blend than the component fabric , in that case calculation of bulk dyeing recipe becomes little complex .
Here we are trying to understand how easily we can solve complexity.
The recipe for a polyester/cotton is developed in lab to a given quality as (50% poly, 50% cotton.) Now in our case we are going to dye a lot which has fabric of Poly/cot blend and also of 100% cotton component.
Due to the recipe system calculating on one weight (kilos). We need to adjust the cotton and polyester dye percentage to compensate FOR VARYING BLENDS. E.g.
Batch weighs 180 kilos 150 kilos = polyester/cotton (50/50 blend)
30 kilos = 100% cotton
Calculate the actual kilos of polyester in the batch:
150 kilos x 0.5 (50%) = 75 kilos
Calculate the theoretical kilos of polyester there should be for the recipe.
180 kilos x 0.5 (50%) = 90 kilos
Recipe as per the folder (based on 50/50 blend).
Poly Red dye 1.0%
Poly blue dye 0.5 %
Poly Yellow dye 0.25%
Divide actual kilos of polyester by the theoretical kilos of polyester E.g
75 kilos/90 kilos = 0.833 compensate ratio
Times the recipe percentage by the compensate ratio
1.0% x 0.833 = 0.833%
0.5% x 0.833 = 0.417%
0.25% x 0.833 = 0.208%
Therefore polyester dyestuffs to weigh =
180 kilos x 0.833% = 1,499g
180 kilos x 0.417% = 751g
180 kilos x 0.208 % = 374g
To check if compensate ratio correct:
Times the actual amount of poly/cotton fabric by the dye percentage in the shade control card.
150 kilos x 1.0% = 1,500g
150 kilos x 0.5% = 500g
150 kilos x 0.25% = 375g
CALCULATE THE COTTON RECIPE of POLYESTER/COTTON RECIPE
Convert the polyester/cotton portion of the batch into kilos of polyester and cotton. E.g
150 kilos of poly/cotton as 50/50 blend =
150 kilos x 0.5% (50%) = 75 kilos of polyester
150 kilos x 0.5% (50%) = 75 kilos of cotton
Add remaining kilos of cotton (within batch) to the above calculations. E.g
Rib to add = 30 kilos of cotton = 75 kilos+ 30 kilos = 105 kilos cotton
Calculate the theoretical kilos of cotton
Theoretical kilos = 180 kilos/ 50% = 90 kilos
Divide the actual kilos by the theoretical kilos of cotton.
105/90 kilos = 1.17% (or 17%) compensate ratio
Cotton recipe in shade control card
Yellow 1%
Red 0.5%
Blue 0.25%
Times the recipe percentage by the compensate ratio
1% x 1.17 (or 17%) = 1.17%
0.5% x 1.17 (or 17%) = 0.585%
0.25% x 1.17 (or 17%) = 0.293%
Therefore COTTON dyestuffs to weigh =
180 kilos x 1.17% = 2,106g
180 kilos x 0.585% = 1,053g
180 kilos x 0.293 % = 527g
To check if compensate ratio correct:
Convert the recipe in the shade control card to 100% cotton.
100/50 x 1.0.% = 2% on the cotton
100/50 x 0.5.% = 1% on the cotton
100/50 x 0.25.% =0.5% on the cotton
Times the actual kilos of cotton by the converted recipe (100% cotton)
105 kilos x 2.0% = 2,100g
105 kilos x 1.0% = 1,050g
105 kilos x 0.5% = 525g
