Basic black acetate lining, deadstock from a NYC designer. Acetate makes a perfect lining fabric, traditionally used in men's tailoring, similar to rayon. Silky smooth, satin on one side, matte on the other, with a cool firm hand and light drape. Right for jacket, coat, vest lining. I make underlayers of lining fabric to layer under tunics and t-shirts using the sleeveless version of V1959.
Acetate is an old-school fabric, man-made from cellulose, a natural material.