Pattern coated - Refers to the width and spacing arrangement of strips of adhesive laid down parallel to machine direction and across the width of pressure sensitive stock during its production.
Peaking - Large singular upheavals in the outer layers of a roll of tape.
Peel adhesion - The force per unit width required to break the bond between a pressure sensitive adhesive tape and the surface to which it has been applied when the tape is peeled back at a controlled angle at a standard rate and condition.
Permanent adhesion - An Adhesive that has been designed to remain permanently in position under the specified service conditions.
Pinholes - Very small defects in a tape, which may permit the passage of light, electricity or water vapour, the minute holes may be in the backing and/or the adhesive.
Plasticization - The softening of an adhesive when exposed to migrating plasticizers or oils.
Plasticised Plyvinylchloride - A tough durable plastic film having excellent resistance to oils, chemicals and many solvents. It has excellent abrasion resistance. It can also be coloured. Its high stretch is due to the addition of a plasticizer.
Polyester film - A strong film having good resistance to moisture, solvents, oils, caustics and many other chemicals. It is usually transparent.
Polyethylene film - A similar film to polyethylene, but stronger and having a higher temperature resistance.
Polyvinylidene Chloride film - A usually very thin transparent film with excellent resistance to acids, water and organic solvents.
Pre-release - The unwanted separation of a tape from its release liner during unwinding.
Pressure sensitive - A term commonly used to designate a distinct category of adhesive tapes and adhesives which in dry form (solvent / water free) are aggressively and permanently tacky at room temperature, and that firmly adhere to a variety of dissimilar surfaces upon mere contact without the need of more than finger or hand pressure. These products require no activation by water, solvent, or heat in order to exert a strong adhesive holding force toward such materials as paper, plastic, glass, wood, cement, and metal. They have sufficient cohesive holding power and elastic nature so that, despite their aggressive tackiness, they can be handled with the fingers and removed from smooth surfaces without leaving a residue.
Pressure sensitive adhesive tape - Pressure sensitive adhesive tape can be defined as a continuous flexible strip of cloth, paper, metal, plastic or foam coated on one or both sides with a permanently tacky adhesive at room temperature that will adhere to a variety of surfaces with light pressure (finger pressure) with no phase change (liquid to solid) and usually in roll form. PSAs can be blends of natural or synthetic rubber and resin, acrylic, silicone or other polymer systems, with or without additives.
Prime coat- A coating on the adhesive side of the backing, which serves as a bonding agent between adhesive and backing.
Printability- The ability of a tape to accept and hold a printed legend, and especially to resist offsetting of the print when unwound from a roll.