Technical gelatins are used in the warp sizing of rayon and acetate yarns. The gelatin size adds strength to the warp and resistance to abrasion so that breakage of the warp is minimized. Gelatin is particularly well suited for this application because of its excellent solubility and film strength. It is applied in aqueous solution along with penetrating oils plasticizers and antifoam agents before weaving and later removed during finishing by washing with warm water.

Panama hats are sized with gelatin. Sizing helps preserve the shape of the hat while imparting resistance to water and dirt. An emerging technology involves the use of gelatin to size quartz fibers for space-age fabrics.