Microfiber is a textile term describing an extremely fine synthetic fiber. To be considered a microfiber, the filament must measure less than one denier, a unit of linear density, making it thinner than a strand of silk and significantly finer than a human hair. This ultra-fine structure has led to its widespread use in high-performance athletic apparel and highly effective cleaning products. This synthetic composition, typically a blend of two different plastics, is the source of its unique performance characteristics and environmental challenges.
The Synthetic Building Blocks
Microfiber textiles are constructed entirely from chemically manufactured polymers derived from petroleum, making these fibers fundamentally plastic. The two primary components used are polyester (polyethylene terephthalate) and polyamide (nylon). A common blend ratio for cleaning cloths is approximately 80% polyester and 20% polyamide. Polyester is valued for its strength and ability to attract oil and dirt, while polyamide is hydrophilic, meaning it absorbs water better. This combination of chemically synthesized polymers gives microfiber its dual action cleaning capability.
Transforming Polymers into Fiber
The creation of microfiber begins with melting polyester and polyamide pellets. These molten polymers are simultaneously extruded through specialized jet moldings, which combine the incompatible polymers into a single, thicker filament, often with polyester forming the core. This filament is cooled to form a continuous thread. The crucial step is the splitting process, where the fabric is submerged in an alkaline solution that chemically corrodes and splits the segments. This action transforms the single filament into multiple, wedge-shaped micro-strands, creating cavernous openings highly effective at trapping particles.
Practical Implications of Synthetic Composition
The synthetic nature and manufacturing process result in a material with a massive surface area, dramatically influencing its functionality. This high surface area allows microfiber to absorb up to seven times its weight in water and excel at picking up liquid and solid debris. The fibers also generate a slight positive electrostatic charge, aiding in attracting and capturing dust. Microfiber’s plastic composition makes it durable, quick-drying, and resistant to mildew, contributing to its longevity. However, this synthetic quality is the source of its primary environmental concern: non-biodegradability. During washing, tiny synthetic filaments shed as microplastic fibers, which are often too small for municipal treatment plants to filter effectively, flowing into rivers and oceans and contributing significantly to global pollution.