Sizing is called heart of weaving. The materials which are used for sizing that is called size ingredients. A gelatinous film forming substance in solution or dispersion applied normally used for warp yarn but sometimes used for weft yarn before weaving is called size.
Size ingredients and their functions: Different types of sized ingredients are used for sizing. Followings are the main size ingredients used for sizing.
- Adhesive: Generally starch of maize, corn, rice, potato and CMC, PVC are used as adhesive. Tamarine is used as adhesive on jute yarn, the adhesive is in granule form that is mixed with water and heated to form a paste which ultimately becomes viscose fluid.
- To increase strength.
- To impart adhesion making the yarn less hairy.
- To increase abrasion resistance.
- To increase smoothness.
- To increase elasticity a stiffness.
- To reduce extensibility.
- Lubricants/Softener: Japan wax, Tallow, Mineral waxes, Vegetable waxes, Animal fats, Mineral oils and Vegetables are used as lubricants.
- It makes the yarn soft and slippery.
- It reduces stiffness.
- It increases yarn smoothness.
- It increases elasticity.
- Anti septic or anti mildew agent: Salicylic acid, Carbolic acid, Zinc chloride, Phenol is used as anti septic agent.
- It prevents mildew formation.
- To preserve size materials for a long time.
- It helps to store the yarn for a long time.
- To protect yarn from bacteria or fungus.
- Deliquescent or hydroscopic agent: Glycerin, Calcium chloride are used as deliquescent agent. Deliquescent agent is those substances which absorb moisture from air.
- It prevents excess drying of yarn.
- It helps to absorb moisture from air.
- To prevent the brittleness of size.
- Weighting agent: China clay, Sodium phosphate are used as weighting agent. These are used especially for those fabric or yarn that is to be solid or grey state.
- It increases the weight of yarn.
- To impart fullness and fell to the fabric.
- Anti foaming agent: Pyridine, Benzene are used as anti foaming agent.
Function: To prevent foam formation.
- Tinting agent: Blue is used as tinting agent.
Function: To increase lusture or brightness.
- Wetting agent: Sulphanol A, soap, avirol, magnesium chloride are used as wetting agent. The drawback of these substances is their high foaming ability and the foam is very stable.
- It increases size exhaust.
- To obtain a uniform distribution of sizing solution on yarn surface.
- It helps to wet yarn instantly.
So, when we will choose size ingredient for sizing we should remember the functions of size ingredients. Various dyes and chemicals manufacturing companies produce size ingredients, choose your favorite one from there.