Starch is a type of ‘sizing’ , a filler used to add body, sheen and luster to limp clothing. All shirts come off the rack with sizing, but sizing is water-soluble; every time the shirt is washed, sizing comes out of the shirt. The main purpose of adding starch, then, is to restore the original body of a garment.
The main ingredient in starch is wheat or , less frequently, corn. The grain is mixed with water, resins and chemicals. As Bill Seitz, of the Neighborhood Cleaners Association, describes it, the starch is literally absorbed by the fabric . Cottton plus wheat is stiffer than cotton alone.
Norman Oehlke, of the International Fabric Institute, adds that starch also enhance soil resistance, facilitates soil removal for the next wash and making ironing easier.
Synthetic fabrics aren’t as receptive to starch as all-cotton garments, so extra chemicals are added to the starch, such as polyvinyl acetate, sulfated fatty alcohols, silicones and, our personal favourite, carboxymethylcellulose.
