Electrical tape (or insulating tape) is a type of
pressure-sensitive tape used to
insulate electrical wires and other materials that conduct
electricity
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...
. It can be made of many
plastic
Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...
s but
PVC (polyvinyl chloride, "vinyl") is the most popular, as it stretches well and gives effective and long-lasting insulation. Electrical tape for
class H insulation is made of fiberglass cloth.
Varieties

A wide variety of electrical tapes are available, some for highly specialized purposes. "The primary tapes used in electrical applications are vinyl, rubber, mastic, and varnished cambric."
[Bob Goodman and Rodney G. Brown (3M).]
Electrical Taping Skills: A Lost Art?
, ''EC&M'', p.2. Electrician
An electrician is a tradesman, tradesperson specializing in electrical wiring of buildings, transmission lines, stationary machines, and related equipment. Electricians may be employed in the installation of new electrical components or the ...
s may use various colors of tape to insulate wire and to indicate the
voltage
Voltage, also known as (electrical) potential difference, electric pressure, or electric tension, is the difference in electric potential between two points. In a Electrostatics, static electric field, it corresponds to the Work (electrical), ...
level and
phase of the wire (colored tape sometimes is called "phasing tape"). When wires are phased, a ring of tape is placed on each end near the termination so that the purpose of the wire is obvious. The following table(s) describe the use of electrical tape.
Tape that is approved for electrical applications will carry an approval label from an agency such as
Underwriters Laboratories.
History

Today, electrical tape is simply "another form of insulation". The original electrical insulating tape was made of cloth tape impregnated with
Chatterton's compound, an adhesive material manufactured using
gutta-percha
Gutta-percha is a tree of the genus ''Palaquium'' in the family Sapotaceae, which is primarily used to create a high-quality latex of the same name. The material is rigid, naturally biologically Chemically inert, inert, resilient, electrically n ...
. This type of tape was often used to insulate
soldered splices on
knob and tube wiring. It was commonly referred to as "friction tape", and had the unique property of being sticky on both sides. Because of this, no matter how it was used it stuck to itself very readily.
In the early 1940s, vinyl plastic emerged as a versatile material for a wide range of applications, from shower curtains to cable insulation. A major ingredient in vinyl film was
tricresyl phosphate (TCP), which was used as a plasticizer. Unfortunately, TCP tended to migrate, giving the surface of the vinyl film an oily quality and degrading every tape adhesive known. Research chemists and engineers at
3M set out to create a dependable, pressure-sensitive tape made of a vinyl film that would have the required electrical, physical and chemical properties.
Experiments were conducted by combining new plasticizers with the white, flour-like vinyl resin. Finally, in January 1946,
inventors Snell, Oace, and Eastwold of 3M applied for a patent for a vinyl electrical tape with a plasticizer system and non-sulfur-based rubber adhesive that were compatible. The first commercially available version of the tape was sold for use as a wire-harness wrapping. This original electrical tape wasn't black.
Tapes formulated for high-temperature were yellow, and later versions were white. Electrically insulating tapes are essential for enhancing functionality and reliability in a wide range of applications. Some of the most popular types include electrically insulating adhesive tape and electrically insulating film, both of which provide reliable electronic isolation and ensure that a direct electrical connection is not made between two or more circuits or their adjacent parts. There is also electrically conducting tape for shielding and similar applications.
White tape, because of its instability in ultraviolet light, was eventually replaced with black tape, although colored vinyl tapes are still used as identification and marking tapes. Black became the standard industry color for vinyl standard tape, primarily because of its ultraviolet resistance. Thicknesses originally were 4 mil (100 μm), 8 mil (200 μm) and 12 mil (300 μm). These were standardized to 7 mil (180 μm) and 10 mil (250 μm) in 1948.
See also
*
List of adhesive tapes
*
Friction tape
References
External links
{{commons category, Electrical tapes
Electrical Taping Skills: A Lost Art?
Electrical Tape Tips by KØFF
*
ASTM
ASTM International, formerly known as American Society for Testing and Materials, is a standards organization that develops and publishes voluntary consensus technical international standards for a wide range of materials, products, systems and s ...
D1000 - Test methods for electrical tapes
Adhesive tape
Dielectrics