Pressure sensitive adhesive (PSA) tape can be defined as a continuous flexible strip of cloth, paper, metal or plastic coated on one or both sides with a permanently tacky adhesive at room temperature which will adhere to a variety of surfaces with light 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.
Single Coated PSA Tapes
An adhesive is applied to only one side of a backing. The backing composition may be paper, polymeric film, foil, nonwoven or high thread count woven cloth. The adhesive composition may be an acrylic, rubber or silicone. Single coated PSA tapes are used in the fields such as electrical, masking, carton sealing, and medical, etc.
Double Coated PSA Tapes
An adhesive is applied to both sides of a backing. The release liners are commonly paper and coated on both sides of the paper with silicone release agents creating a differential release. The pressure sensitive adhesive is coated on both sides of the carrier which is typically a polymeric film such as 0.5 mil polyester. The adhesive on each side of the carrier may be the same or different chemistries and may have the same or different coating thicknesses. Examples of double coated PSA tapes include mounting, medical and membrane switch.
Reinforced PSA Tapes
In addition to the backing and adhesive, reinforced PSA tapes include a reinforcement layer of woven or knitted cloth or glass strands parallel to the machine direction. Typical backings include polymeric films such as polyethylene and polyester. Rubber-based adhesives are the most common but others can be used. Examples of reinforced PSA tapes are duct and filament.
Unsupported PSA Tapes
Unsupported PSA tapes consist of release liners and adhesives. The release liners are commonly paper and coated on both sides of the paper with silicone release agents creating a differential release. Acrylic adhesives are commonly used in this application. Examples of unsupported tapes are envelope sealing and splicing.
This article is reproduced from Pressure Sensitive Tape Council.