WALL MIXER:
A slow drum mixer consisting of a single shaft with one or several paddles.

WATER ABSORPTION:
The measure of the amount of water which will be soaked up by a tape under stated conditions and retained by it.

WATER PENETRATION:
Tapes ability to prevent water passing through the tape itself.

WATER VAPOR TRANSMISSION RATE (W.V.T.R ) :
The weight of water vapour passing through a defined area of tape in a fixed period of time; the conditions of temperature and humidity are specified. Usually a desiccant is sealed in a contained with the tape and exposed to a humid atmosphere.

WEB:
Synonymous with backing or substrate.

WETTING:
Ability of an adhesive to flow and come into intimate contact with surfaces to which it is applied.

WIND-UP:
Equipment located at the exit end of the coater that winds the coated tape onto a bundle roll.

WOVEN:
Textile fabric formed by interlacing cross yarns with continuous machine direction yarns. A NON-WOVEN, is a fabric like material made from fibers that are laid down randomly in a process similar to paper making, fibers are then bonded together with binder or heat and pressure.

WRINKLES:
Distortions in backing materials represented by creases, folds and other minor ridges that cause defects the nature of the web.