Polyesters microfibers

Microfibers allow a fabric to be woven that is lightweight and strong. They can be tightly woven so that wind, rain, and cold do not easily penetrate. Rainwear manufacturers use microfibers for this reason. They also have the ability to allow perspiration to pass through them. Thus, so-called microfiber athletic-wear is becoming more commonplace. Microfibers are also very flexible because the small fibers can easily slide back and forth on one another. The first fabric made from microfiber was Ultrasuede in which short polyester microfibers were imbedded into a PU base. Today microfibers are made mainly from polyesters, nylon, acrylic, and rayon fibers. 

The shape of the microfiber influences the end properties. For instance, Tomen has developed Technofine , a polyester microfiber with a W-shaped cross section. The increased surface allows a more rapid transport of water away from the skin and also increases the evaporation rate, making garments sowed from it quicker-drying and more adsorbent. 

Wong, W., Chan, K., Yeung, K.W., Lau, K.S., 2000b. Pulsed UV laser and low temperature plasma modification on polyester microfiber effect of dyeing properties. J. Text. Eng. 46 (2), 32 1. 

In 1970, Miyoshi Okamoto, a scientist from Toray Industries, created the first microfiber. A few months later his colleague Toyohiko Hikota developed a process that allowed the production of fabric that was later trademarked as Ultrasuede . Ultrasuede was produced from such thin PET polyester fibers that a pound of them laid end-to-end would reach from the earth to the moon and back. Ultrasuede is soft and supple, resistant to stains and discoloration, and machine-washable and dry-cleanable. 

Microfibers are also made by simple extrusion through a spinneret with a smaller hole than normally employed for fiber production. The third method involves spinning a bi-component fiber and using a solution to split the fiber into smaller pieces. Initially, bi-component fibers in the range of 2-4 denier are spun and then split into microfibers. If a 32-segment pie of nylon-polyester fiber is used, the final fineness is on the order of 0.1 denier. Brushing and other techniques can be used to enhance the effects. Hollow fibers are also being used... 

Their inexpensive production from petrochemical raw materials and excellent textile properties alone and in combination with natural fibers guarantee PES fibers universal applicability. Beside technical applications, uses include clothing, especially mixed with wool for suiting and trouser materials and mixed with cotton for shirts, raincoats, trousers, and casual wear. Pure PES fibers, especially in textured form, are employed in the knitwear sector. Polyester has found a wide field of application in the microfiber sector. 

Microdenier Fibers. The first commercial production of microfiber in the United States was in 1989 by the DuPont Company. Today microfibers are produced in a variety of synthetic fibers (i.e., polyester, nylon, acrylic, etc.) A microfiber is a fiber that is less than one denier per filament. Yams made from microdenier filaments are able to give silklike hand to fabrics. 

Mkrofiber or microdenier fiber has become important in the fashion industry. The reason for this is the fine size of microfiber. It is finer than any natural textile fiber such as silk, wool, etc. Microfibers are nothing but polyester fibers with diameter <5 xm (or less than 1 den). Such fineness allows more filaments to be packed in the yarn. Fabrics using such tightly bundled filaments are said to have a buttery texture like velour or washed silk. They also have the desirable characteristics of polyester, namely wrinkle-resistance and durability. Such fabrics are used in men s wear, women s wear, rainwear, active wear and home furnishings. 

The first mio ofiber (polyester) is invented by Toray Industries in Japan. The first fabric comprised of microfibers. Ultrasuede, is also introduced The liquid crystal display (LCD) is invented by James Fergason The first single chip microprocessor, Intel 4004, is introduced The video cassette recorder (VCR) is invented by Charles Ginsburg Hydrogels are synthesized... 

The two polymer components do not have to differ in chemical nature. They can differ only in physical parameters such as molecular weight. Usually, it is desirable that the two components have good mutual adhesion, but not always. Polyolefines do not bond well with polyesters or polyamides and this fact is exploited in the formation of microfibers (see later). 

The first commercial microfibers were produced in Japan [76] in the 1970s and were made by spinning a bicomponent fiber with polyester fibrils dispersed in a matrix polymer in the islands in a sea configuration [77]. This was drawn into fibers and processed into fabric and finally the matrix polymer was dissolved, leaving tiny polyester fibrils. These were processed into a synthetic suede material marketed as Ultrasuede. The polyester fibrils were extremely fine, less than 1 pm in diameter. The process was expensive, but the product was successful. At the same time, numerous variations on this theme later followed. One ingenious idea by Sato and coworkers used was a blend of PET in a PET-sulfoisophthalate copolymer rich in SOsNa groups, which dissolved readily in aqueous base leaving the unaffected PET. 

Ultrafine fibers are generally called microfibers. The definition of microfiber, as accepted in the trade, is a fiber finer than 1.2dtex for polyester, and finer than l.Odtex for polyamide. These fibers are finer than luxury natural fibers such as silk. The most popular technology to... 

There has been recent success in the production of superfils from polyesters, polyamides, and other polymers using a variety of methods. These fibers include everything from fine fibers (1 dtex-0.1 dtex) to the actual microfibers (0.3 tex-0.1 dtex) and ultrafine fibers (10 dtex) and ultrasuperfine fibers (lO dtex). These fibers are much finer than natural silk thread ( 1.3 dtex) [81]. 

Polyesters, such as PET, are now widely used in the manufacture of fibers for textiles and other apph-cations. While PET has many desirable properties that make it suitable for manufacturing fibers, there is a continuing need for polyester fibers that have improved properties, or properties that are different from PET, thereby opening new uses for polyester fibers. For example, PEN has found applications in high performance sailcloth materials or in industrial filtration applications. Microfibers can be obtained from fibers using a laser thinning method [98]. 

Microdenier. In the late 1980s, producers of polyester introduced microdenier products, that offered softer, more luxuriant handle to fabrics. Some acrylic producers have followed. There are no appreciable technical hurdles to producing a fiber with a denier of0.6-0.9 (0.66-1.00 dtex), bnt unless commensurate changes are made in line speed or the nnmber of spinneret holes, productivity will suffer Acrylic microfibers on the market are all staple products, with Sterling in the United States producing a 0.8 dpf acrylic staple product named MicroSupreme and Solutia a 0.95 dpf prodnct called Ginny. Mitsubishi Rayon offers H-129 (1.0 dtex). 

Nanocomposite conventional mesoscale fibers (textile fibers that carry nanoparticulate filler) are produced via conventional fiber-spinning techniques by incorporating well-dispersed nanoparticles into the spinning dope. For instance, an intercalated poly(ethylene terephthalate) (PET)/organo-montmorillonite (MMT) nanocomposite prepared by in situ polymerization of the polyester in the presence of MMT clay was successfully melt spun into microfibers (Guan, G.-H., et al. 2005). Melt-spun conventional fibers of... 

The first commercial microfibers were obtained by way of co-extmsion of polyesters or polyamides with another polymer, mostly polystyrene. Due to the lack of compatibility, the sections of different components usually separate during neck drawing or during the finishing process with the aid of mechanical force or some chemical agents. The need of dissolution makes such processes exceptionally cumbersome and expensive, and right now, some water-soluble polymers are used [45]. The Japanese first introduced microfibers in an attempt to reproduce silk-like properties with the... 

Microfibers, such as Cyphrex microfibers, are usually less than 5 pm in fibre size, have high surface-area-to-mass ratio, and offer a narrow diameter distribution. They are made from various polymers including polyester, polyamide, and PP. They not only have smaller fibre diameters, but also have various unique fibre cross sections, such as round, flat and wedge shapes. 

The first microfiber (polyester) is invented by Toray Industries in Japan ... 

Microfibers are fibers that are less than one denier per filament—100 times finer than a human hair. Textiles produced with microfiber yams are softer and possess better drape than conventional products. Microfibers can be made from polyester, polyamide, polypropylene, and many other fiber-forming polymers. These fibers can be made into fabrics with dimensionally stable, lightweight, waterproof, and easy-care characteristics. 

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