Pigment: An insoluble, finely divided substance , such as titanium dioxide, used to deluster or color fibers, yarns, or fabrics.

Pile: 1. A fabric effect formed by introducing tufts, loops, or other erect yarns on all or part of the fabric surface. Types are warp, filling, and knotted pile, or loops produced by weaving an extra set of yarns over wires which are then drawn out of the fabric. 2. In carpets, pile refers to the face yarn, as opposed to backing or support yarn. Pile carpets are produced by either tufting or weaving.

Pile: A wood, paper, or plastic support, cylindrical or slightly tapered, with or without a conical base, on which yarn is wound.

Plied Yarn: A yarn formed by twisting together two or more single yarns in one operation.

Ply: 1. The number of single yarns twisted together to form a plied yarn, or the number of plied yarns twisted together to form cord. 2. An individual yarn in a plied yarn or cord. 3. One of a number of layers of fabric (ASTM). 4. The number of layers of fabric, as in a shirt collar, or of cord in a tire.

Plying: Twisting together two or more single yarns or ply yarns to form, respectively, ply yarn or cord.

Polyester Fiber: A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer composed of at least 85% by weight of an ester of dihydric alcohol and terephthalic acid (FTC definition). Fiber forms produced are filament, staple, and tow. Polymerization is accomplished at a high temperature, using a vacuum. The glycol and ester reaction forms a polymer chain, releasing methanol. The filaments are spun in a melt-spinning process, stretched several times their original length, orients the long chain molecules and gives the fiber strength.

Characteristics: Polyester fibers have high strength and are resistant to shrinking and stretching. Fabrics are quick-drying and tend to have wrinkle resistance and crease retention, wet and dry. Polyester is used alone and in blends.

Polyethylene Fiber: A man-made fiber made of polyethylene, usually in monofilament form; although work has been done on continuous filament yarns and staple. Ethylene is polymerized at high pressures and the resulting polymer is melt-spun and cold drawn. It may also be dry-spun from xylene solution.

Characteristics: Polyethylene fibers have a low specific gravity, extremely low moisture regain, the same tensile strength wet and dry, and are resistant to attack by mildew and insects.

Polymer: A high molecular chain-like structure from which man-made fibers are derived, produced by linking together molecular units called monomers.

Print: A fabric with designs applied by means of dyes or pigments used on engraved rollers, blocks, or screens.