Cloth Tapes Information
Cloth and fabric tapes provide a higher tensile strength than typical adhesive tapes, and also have a more flexible composition. These tapes incorporate woven and non-woven carriers as the primary component for their additional ruggedness. A large variety of cloth tapes are produced to meet the market demands of the medical, construction, textile, HVAC, electrical, plumbing, and manufacturing industries.
Cloth Tape Operation
Cloth tape earns its high-strength reputation from the use of industrial fabrics as the backing for the adhesive. This increases the tensile strength of the product, and enhances the geometric adaptability of the product during application. Other common benefits of utilizing cloth and fabric as the carrier include heat resistance, insulation, abrasion resistance, and breathability. Similar to other types of tape, cloth tape's usage is largely determined by compatibility with the bonding substrate, most notably the capabilities of the adhesive. Cloth tapes are most often pressure-sensitive activated, and some cloth tapes may feature double-sided adhesives.
The most common form of cloth tape would be the iconic duct tape. Duct tape has performed well-enough in universal applications that it has supplanted its original construction and abilities as a seam-sealer for HVAC operations. The threads of duct tape tend to be polyester, nylon, rayon, or fiberglass; specialized foil and metal-backed tapes are now recommended for duct work.
Cloth Tape Production
Despite proprietary carrier designs, cloth tape production resembles that of any adhesive tape.
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||Acrylic-based adhesives reach their maximum adhesion almost immediately upon application, have adequate resistance, require no preparation, and have good sheer and peel strength.|
||Epoxy resins are adhesives that exhibit high strength and low shrinkage during curing. Epoxies are known for their toughness and resistance to chemical and environmental damage.|
||Non-adhesive tapes, films, or laminates do not have an applied adhesive. These tapes are self-adhering and rely on a high coefficient of friction to remain adhered.|
||Pressure sensitive adhesives (PSAs) or contact adhesives are aggressively and permanently tacky at room temperature in dry (solvent free) form. They adhere firmly to a variety of dissimilar surfaces upon contact, requiring only the application of finger or hand pressure. PSAs do not require water, solvent or heat activation in order to exert a strong adhesive force on materials such as paper, plastic, glass, wood, cement and metal. PSAs have a sufficiently cohesive holding and elastic nature so that despite their aggressive tackiness they can be manipulated by hand and removed from smooth surfaces without leaving a residue. This is the most common adhesive of electrical tapes and as such, is not usually specified on product packaging.|
||Adhesives with a rubber-based chemical structure have highly flexible bonds that are based on butadiene-styrene, butyl, polyisobutylene, or nitrile compounds.|
||Silicone adhesives and sealants have a high degree of flexibility and very high temperature resistance (600°F). While available as a pressure sensitive application, some silicone adhesives may require ventilation, or UV or EB radiation to cure.|
||Thermosetting adhesive tape has a thermally activated bond that is optimized by high heat, pressure, and operator patience.|
||Fabric materials like cotton can be used as the carrier material to improve tensile strength, heat resistance, and electrical resistance. Cloth carriers can further be segmented into woven and non-woven cloth materials. Non-woven fibers are less strong than woven fabrics, but have additional flexibility.|
||These are similar to cloth carriers, but are reinforced with glass or fiberglass particles to enhance heat resistance to over 300° F. Other glass and fiberglass tapes have enhanced flame retardation and thermosetting properties.|
||Polyethylene teraphthalate/polyester carriers have high resistance to solvents, and have good aging and clarity characteristics.|
||Adhesive-coated polyolefin foams include an adhesive that is protected by a liner in the form of a tape, film or laminate.|
Some manufacturers of cloth tape may elect to establish an impermeable barrier on the cloth by applying PTFE, polyethylene, rubber, a liquid polymer, or metal foil. This will alter the capabilities of the tape accordingly.
Common Types of Cloth Tape
|Duct tape is backed by loosely woven fibers that are then sealed with polyethylene. Duct tape is most often gray in color, but other designs are common. Duct tape is strong, versatile, and waterproof, but is susceptible to moderate heat (most likely due to the rubber adhesive). Duct tape is a misnomer; it is not recommended for HVAC use. Adhesive residue from removal is common. Industrial-grade and consumer-grade duct tapes are available.||
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|Gaffer's tape is a rugged, cloth-backed tape with a synthetic rubber adhesive. It is used in conjunction with electrical and audio-visual components due to its lack of residue upon removal.||
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Medical tape is a woven cotton, woven microfiber, or woven polyester type of adhesive tape explicitly meant to adhere to human skin. The tape is used to hold bandages and dressings, tubing, and in general first aid applications. The tape is formulated to be hypoallergenic, breatheable to promote healing, and possibly translucent to monitor the wound. Many types of medical tape include zinc oxide to prevent bacteria growth. The acrylic adhesive, though waterproof, does not leave a residue. The stiff fabric and application can support and compress body parts.
Closely related to medical tape is athletic tape, which is common for simple sports-related injuries and uses.
Image credit: 3M
|Cambric tapes are a type of cotton electrical tape with yellow insulating varnish. They exhibit excellent electrical insulating properties. These tapes come in non-adhesive varieties, and are resistant to abrasion and puncture. They are designed to insulate bus bars, motor leads, and service drop connections.||
Image credit: 3M
|Friction tape is a cloth tape that has been infused with rubber adhesive to increase friction and grip. It can also act as an insulator, and is corrosion resistant. Friction tape has a two-sided adhesive. It is commonly applied to handles.||
Image credit: Find Tape
|Glass and fiberglass tapes have a temperature-resistant silicone adhesive. The fabric exhibits high strength, abrasion resistance, and weatherability. It is suitable for splicing and shielding. Fiberglass tapes are used frequently in covering drywall joints. This type of tape frequently has a polymer coating, or even a rubber infusion.||
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|Nuclear tape consists of a polyethylene coated coated cloth scrim with a rubber adhesive, both resisting temperatures of 200 ° F. It is commonly used in nuclear operations and ship repairs. It is designed for use with nickel-based alloys and austenitic stainless steels.||
Image credit: Find Tape
Packaging Tape Specifications
For tapes, there are two important geometrical aspects to consider: width and thickness. Length is unimportant because this is determined by the user at the point of application.
Width is the measurement across predetermined edges of the tape. Tapes can be cut by the customer to smaller widths.
Thickness is the distance between the two, flattened surfaces of the tape (carrier and adhesive). It is usually expressed in mils or thousandths of an inch, and is measured under pressure with a gauge.
- Tensile strength is the maximum load the tape can withstand. Cloth tapes exhibit some of the highest strength ranges available.
- Peel strength is the amount of force needed to separate two bonded surfaces. This is commonly rated in ounces per square inch to stainless steel. This is separate from the peel strength for the tape liner, which is considerably less.
- Temperature resistance is the amount of heat the tape can be subjected to without compromising the tape's performance. Cloth tapes such as glass, fiberglass, and nuclear-grade tapes remain uncompromised at temperatures over 200 ºF.
- Abrasion resistance is the level of scratch resistance and ruggedness of the tape.
- Transparent products allow the transmission of light. A tape is rated as transparent if 10-point type can be read easily when the tape is applied directly over it.
- Once applied, products become permanently bonded to the substrate.
- Weather resistant products are suitable for outdoor use and resistant to ultraviolet (UV) light, cold, heat, water or other weather conditions.
Underwriter's Laboratory provides it's quality seal to many tapes that it deems sufficiently useful. Surgical tapes must pass U.S. FDA standards, or its respective marketplace's federal medical ministry. Pressure sensitive, glass cloth tapes are recommended to adhere to ASTM standard D2754 - 10. Cambric tape quality is compared with ATSM D295 and D1000. Quality-regarded friction tapes will meet the criterion of ASTM D69 - 12 and ASTM D4514 - 12. Though UL 181A and 181B are published as duct tape standards, these are standards for HVAC tape. Unfortunately, common cloth duct and gaffer's tapes are largely ignored in regards to individual product benchmarks. These products are often tested according to the standards of the Pressure Sensitive Tape Council's self-regulatory control board, which include peel strength (PTSC 101 & 105), tensile strength (PTSC 131), and total thickness (PTSC-133). ASTM D3330 also includes several methods of testing the adhesion of tape.