It is a process in which 2 to 3 varieties of cotton are mixed in specific proportion to get the optimum mix which produce quality yarn. Different cottons give different count.
Objectives of mixing:
To get uniform quality of yarn.
To improve processing performance.
To achieve the function and application.
To get the fency effect.
To decrease the production cost.
For example: Jayadhar and veernar are used for producing 10S to 20S count of yarn. Where as LK33, LK45, MCU5 are producing 40S to 60S yarn. Similarly, S4 (shankar), suvin, Varalakshmi are used for very fine count above 60S to 100S. super fine cotton i.e. Sea island cotton used for producing 120S.
To determine cotton A and cotton B percentage Atira method is used. Any cotton to be selected for process will depend on the end product to be produced like shirting, suiting, dress material, curtain cloth etc.
Types of mixing:
Bale mixing: Mixing can be done before the blowroom.
Flock mixing: Mixing is done in the blowroom.
Lap mixing: Mixing is done at the scutcher.
Web mixing: Mixing is done at ribbon lap machine or drawframe.
Sliver mixing: Mixing is done at drawframe or at comber.
Fiber mixing: Mixing is done at card or rotor spinning machine.
Roving mixing: Mixing is done at ring spinning machine.
Mixing of 2 different kinds of fibers is called blending. The total quantity of 2 fibres mixed will be equal to 100. The proportion of these fibers to be mixed will mainly depend on end use.
Objectives of blending:
To improve functional properties.
To decrease the production/manufacturing price.
To improve the process performance.
To improve aesthetics of the fabric.
For example: 67/33 p/c blend means 67% of polyester is mixed with 33% of cotton. Here cotton is low and percentage of polyester is high. Because the application demands higher strength, more durability, easy care etc. which is given by polyester whereas cotton gives good absorption as polyester is poor in absorption. Viscose/wool is a rare blend.
Types of blending:
Bale blending: Blending can be done before the blowroom.
Flock blending: Blending is done in the blowroom.
Lap blending: Blending is done at the scutcher.
Web blending: Blending is done at ribbon lap machine or drawframe.
Sliver blending: Blending is done at drawframe or at comber.
Fiber blending: Blending is done at card or rotor spinning machine.
Roving blending: Blending is done at ring spinning machine.
Advantages of blending:
Blending improves the final properties.
A property may be absent in one fiber but the same property may be present in another fiber. By mixing the 2 fibers we get the right blend.
To improve the physical and chemical properties.
To produce a yarn which is meant for specific application.
Some examples of blended fabrics are:
Polyester/cotton, nylon/wool, nylon/acetate, ramie/ acrylic, ramie/polyester, wool/cotton, linen/silk, linen/rayon, silk/wool, rayon/cotton, wool/synthetics, rayon/synthetics etc.
The common blend percentages as per the following.
Difference between mixing and blending: