Percale refers to a tight weave of the fabric; one yarn over, one yarn under. Used with cotton it produces a very strong and soft fabric with a (semi) matt finish. Cotton percale is also lighter in weight and more breathable than cotton sateen.
Thread count refers to the number of threads woven per inch. In general; the higher the thread count, the more denser and softer to the touch a fabric becomes, provided that high-quality cotton and single-ply thread is used. Since we follow these high standards, our 200 and 300 thread count fabrics already are of good quality and our 400 or 500 TC will be noticeably softer and slightly heavier.