Microfiber

thumb|Microfiber cloth suitable for cleaning sensitive surfaces

thumb|Microscopic view of a microfiber cloth

Microfiber (US English) or microfibre (UK English) is a synthetic fiber made of threads finer than one denier or one detex with a diameter of less than ten micrometers.

The most common types of microfiber cloth are made of polyesters, polyamides (e.g., nylon, Kevlar, Nomex), and combinations of polyester, polyamide, and polypropylene. Microfiber cloth is used to make mats, knits, and weaves, for apparel, upholstery, industrial filters, and cleaning products. The shape, size, and combinations of synthetic fibers are chosen for specific characteristics, including softness, toughness, absorption, water repellence, electrostatics, and filtering ability.

Microfiber cloth is used to clean scratch-prone surfaces such as display devices, glass, and lenses. Microfiber cloth makes use of van der Waals force to remove dirt without scratches.

History

Production of ultra-fine fibers (finer than 0.7 denier) dates to the late 1950s, using melt-blown spinning and flash spinning techniques. Initially, only fine staples of random length could be manufactured and very few applications were found. Then came experiments to produce ultra-fine fibers of a continuous filament: the most promising experiments were made in Japan in the 1960s, by Miyoshi Okamoto, a scientist at Toray Industries. Okamoto's discoveries and those of Toyohiko Hikota led to many industrial applications, including Ultrasuede, one of the first successful synthetic microfibers, which entered the market in the 1970s. Microfiber's use in the textile industry then expanded. Microfibers were first publicized in the early 1990s, in Sweden, and saw success as a product in Europe over the course of the decade.

Preparation of microfibers

alt=A circle cross section resembling the cross section of an orange with the core and spokes in red labeled "1" and the wedges in black labeled "2".|thumb|Illustration of the cross section of an "orange" bicomponent filament before splitting. The red (1) is often nylon while the black (2) is often polyester.

Microfibers are produced either by twisting long extruded continuous filaments or by combining small staple fibers using heat and/or force. Continuous filaments can either be single component, most often polyester, or bicomponent fiber, most often polyester and polyamide (nylon). To make even smaller fibers, bicomponent fibers are often split. Another bicomponent continuous filament microfiber production method, called island-in-sea, involves extruding "islands" of thin polymer fibers (often polyester, nylon, or both) in a sacrificial "sea" matrix which is later dissolved away using a solvent, leaving only the thin "island" strands behind.

Cloths and mops

Microfiber products used for consumer cleaning are generally constructed from split conjugated fibers of polyester and polyamide. Microfiber used for commercial cleaning products also includes many products constructed of 100% polyester. Microfiber products are able to absorb oils especially well and are not hard enough to scratch even paintwork unless they have retained grit or hard particles from previous use. Due to hydrogen bonding, microfiber cloth containing polyamide absorbs and holds more water than other types of fibers.

Microfiber is widely used by car detailers to handle tasks such as removing wax from paintwork, quick detailing, interior cleaning, glass cleaning, and drying. Because of their fine fibers which leave no lint or dust, microfiber towels are used by car detailers and enthusiasts in a similar manner to a chamois leather.

Microfiber is used in many professional cleaning applications, for example in mops and cleaning cloths. Although microfiber mops cost more than non-microfiber mops, they may be more economical because they last longer and require less effort to use.

Microfiber textiles designed for cleaning do so on a microscopic scale. According to tests, using microfiber materials to clean a surface reduces bacteria by 99%, whereas a conventional cleaning material reduces bacteria by only 33%. Microfiber cleaning tools also absorb fat and grease and their electrostatic properties allow them to attract dust strongly.

Microfiber cloths are also used to clean photographic lenses as they absorb oily matter without being abrasive or leaving a residue, and are sold by major manufacturers such as Sinar, Zeiss, Nikon and Canon. Small microfiber cleaning cloths are commonly sold for cleaning computer screens, cameras, phones and eyeglasses.

thumb|Cloth for cleaning glasses

Microfiber is unsuitable for some cleaning applications as it accumulates dust, debris, and particles. Sensitive surfaces (such as all high-tech coated surfaces e.g. CRT, LCD and plasma screens) can easily be damaged by a microfiber cloth if it has picked up grit or other abrasive particles during use. One way to minimize the risk of damage to flat surfaces is to use a flat, non-rugged microfiber cloth, as these tend to be less prone to retaining grit.

Rags made of microfiber must only be washed with regular laundry detergent, not oily, self-softening, soap-based detergents. Fabric softener must not be used; the oils and cationic surfactants in the softener and self-softening detergents will clog up the fibers and make them less absorbent until the oils are washed out. Hot temperatures may also cause microfiber cloth to melt or become wrinkled. The ball, manufactured by Spalding, did not require a leather ball's "break-in" period of use. Microfiber has the ability to absorb water and oils, making the ball less slippery as sweat from players touching the ball is better absorbed. On January 1, 2007, the league scrapped the use of all microfiber balls and returned to leather basketballs.

Environmental and safety issues

Microfiber textiles tend to be flammable if manufactured from hydrocarbons (polyester) or carbohydrates (cellulose) and emit toxic gases when burning, more so if aromatic (PET, PS, ABS) or treated with halogenated flame retardants and azo dyes. Their polyester and nylon stock are made from petrochemicals, which are not a renewable resource and are not biodegradable.

For most cleaning applications they are designed for repeated use rather than being discarded after use. An exception to this is the precise cleaning of optical components where a wet cloth is drawn once across the object and must not be used again as the debris collected are now embedded in the cloth and may scratch the optical surface.

Microfiber products also enter the oceanic water supply and food chain similarly to other microplastics. Synthetic clothing made of microfibers that are washed release materials and travel to local wastewater treatment plants, contributing to plastic pollution in water. A study by the clothing brand Patagonia and University of California, Santa Barbara, found that when synthetic jackets made of microfibers are washed, on average of microfibers are released from the washing machine. These microfibers then travel to local wastewater treatment plants, where up to 40% of them enter into rivers, lakes, and oceans where they contribute to the overall plastic pollution. Microfibers account for 85% of man-made debris found on shorelines worldwide.

Regulations

United States

In 2018, the state of California passed a bill which would mandate that all clothes made with 50%+ polyester have warning labels regarding microfiber shedding in laundry. Then in 2024, the state passed a bill mandating that all new washing machines in California must have microfiber filtration systems from 2029 and on.

In 2018, the Connecticut General Assembly passed 2 bills that would educate consumers on the dangers of microfibers through awareness camps and programs.However, in recent years, there have been more serious efforts done to regulate microfiber pollution nationwide, especially as household laundry has become an ever more known source of the issue. In 2020, then President Donald Trump signed into law the Save Our Seas 2.0 act, and in it the Interagency Marine Debris Coordinating Committee (IMDCC) to release a report on microfiber pollution and how the government could take measures to reduce the issue. There has also been legislation introduced to take a harder approach against microfiber pollution, with congressman Mike Levin introducing the "Fighting Fibers Act of 2025" in July 2025, which if passed would require all washing machines nationwide to have microfiber filtration systems installed by 2030.

In 2023, the U.S. Environmental Protection agency had proposed multiple solutions to the issue of microfibers including reducing laundry emissions, creating non-degradable textiles, and containing microfibers in areas that prevent them from escaping into the environment.