Pressure-sensitive tape, known also in various countries as PSA tape, adhesive tape, self-stick tape, sticky tape, Sellotape, or just tape, is an adhesive tape that will stick with application of pressure, without the need for a solvent (such as water) or heat for activation. It can be used in the home, office, industry, and institutions for a wide variety of purposes.
It will stick without the need for a solvent such as water or heat for activation. By contrast, "gummed" or "water activated" adhesive tapes require warm water for activation and "heat activated" tapes require heat.
Single-sided tapes allow bonding to a surface or joining of two adjacent or overlapping materials. Double-sided tape (adhesive on both sides) allows joining of two items back-to-back.
Pressure-sensitive adhesive was first developed in 1845 by Dr. Horace Day, a surgeon. Commercial tapes were introduced in the early twentieth century. Hundreds of patents have since been published on a wide variety of formulations and constructions.
Varieties of PSA tape
Adhesive transfer tape does not have a backing material. Instead, adhesive is on a double-coated release liner for winding on a roll. Sometimes the adhesive is sandwiched between two liners.
Archival tape is similar to transparent office tape, with low-acid adhesives that will not degrade surfaces they are applied to, protecting documents from damage during long-term storage.
Box-sealing tape (also "packing tape"; "parcel tape", UK) is a type of packaging tape which is clear or opaque, and used for closing packages for shipment. It is usually two inches (48 mm) or three inches (72 mm) wide and is made of a polypropylene or polyester backing.
Drafting tape is similar to masking tape, but with lower tack adhesive so that it may be removed without damaging or leaving residue on paper or other delicate surfaces, and also has pH maintained at 7 so as not to damage the substrate.
Duct tape usually has a plastic-coated fabric backing and a strong adhesive.
Double-sided tape has adhesive on both sides of a backing material, for attaching two surfaces together.
Electrical tape (or insulating tape) stretches to conform to irregular objects, and is made of materials like vinyl that do not conduct electricity.
Filament tape or "strapping tape" has filaments (usually fiberglass) embedded into the adhesive for extra strength.
Transparent office tape is used for repairing torn paper products, sealing envelopes, general holding, etc. It is a transparent film of cellophane, cellulose, polypropylene, or other plastic, with an acrylic or synthetic rubber–based adhesive. Clear tape with a matte finish is branded "Scotch Magic Tape" or called "invisible tape". Clear tape is sold in pre-filled single-use tape dispensers and in "refill" rolls for permanent desktop tape dispensers. Famous brands include Sellotape, Scotch Tape, Duck, Tesa, LePage's, Texcel, etc.
Backing. The primary component of tape upon which an adhesive is applied. Examples are cloth, paper, metal foil, plastic film, etc.
Conformability. Ability of a tape to make total contact with a rough or uneven surface.
Creped. Paper that has small "folds" to provide stretchability and conformability.
Double-coated, or two-sided tape. Pressure-sensitive tape with adhesive on both sides of the carrier material.
Gapping. Openings between layers of tape within a roll.
Release coating. A very thin coating applied to the impervious tape backing so as to allow the tape to be unwound at a controlled level.
Substrate. The substrate is the material to which the PSA tape must adhere.
Tack. The sticky feel of the tape. It is the initial adhesion without rub-down.
Telescoping. A sideways sliding of the tape layers, one over the other, so that the roll looks like a funnel or telescope.
Unwind. The force to remove or unwind the tape from a roll.
PSA tape standards
The PSA industry is in the process of unifying the several standards presently in use.
The most active organizations are:
ISO International Organization for Standardization: A European AFNOR committee is currently active in the definition of international standards; some of the most common test methods, such as Peel Adhesion, Static Shear Adhesion, Break Strength, and Elongation are presently ISO standard
ASTM: ASTM International has several Technical Committees which write standards related to pressure-sensitive tape.
PSTC: Pressure Sensitive Tape Council (tapes, North America)
TLMI: Tag & Label Manufacturers Institute (labels, North America)
AFERA: European Association for the Self Adhesive Tape Industry (tapes, Europe)
FINAT: Féderation internationale des fabricants et transformateurs d'adhésifs et thermocollants (labels, Europe)
JATMA: Japanese Adhesive Tapes Manufacturers Association
ASTM International has dozens of standards related to pressure-sensitive tape. Some of them are for general types of PSA tape; others are for specific types. For example, ASTM D1000 has test methods for electrical tapes. There are ASTM specifications for many tapes including D2301 for vinyl electrical tape, D5486 for box-sealing tape, etc. Several of the ASTM test methods are coordinated with PSTC, other trade associations, and other international organizations.
Following are a few examples of some ASTM standards and counterparts:
D3121 Standard test method for tack of pressure-sensitive adhesives by rolling ball
D3330 Standard Test Method for Peel Adhesion of Pressure-Sensitive Tape
D3654 Standard Test Methods for Shear Adhesion of Pressure-Sensitive Tapes
D3759 Standard Test Method for Breaking Strength and Elongation of Pressure-Sensitive Tapes
D3811 Standard test method for unwind force of pressure-sensitive tapes
D5750 Standard Guide for Width and Length of Pressure-Sensitive Tape
Life cycle assessments of the tape and the item being taped are useful to identify and improve possible environmental effects. For example, there may be instances where the use of a PSA tape, compared to an alternative solution, improves the overall environmental impact, or vice versa.
Reuse or recycling are sometimes aided by a tape being removable from a surface. If a tape remains on an item during recycling, a tape should be chosen which does not hinder the recyclability of the item. For example, when taped corrugated boxes are recycled, film-backed box-sealing tapes do not hinder box recycling; the adhesive stays with the backing and is easily removed.