① Identification methods include touch, visual inspection, combustion, microscopy, dissolution, drug color development and infrared spectrum. In the actual appraisal, it is often necessary to use a variety of methods, comprehensive analysis and research to get the results.
② The general identification steps are as follows:
A. First, identify natural fibers and chemical fibers by combustion method.
B. If it is natural fiber, identify various plant fibers and animal fibers through microscopic observation. If it is a chemical fiber, it should be distinguished one by one according to the difference of melting point, specific gravity, refractive index and solubility of the fiber.
C. When distinguishing blended fibers from blended yarns, it is generally possible to observe and confirm several fibers with a microscope, and then identify them one by one by an appropriate method.
D. For dyed or finished fibers, dyeing and stripping or other appropriate pretreatment are usually needed to ensure the reliability of identification results.
Non-professional, general methods mainly rely on hand feeling and combustion method:
Acrylic: fluffy, furry.
Melting and burning near the flame, melting and burning in the flame, burning and splashing quickly after leaving the flame, with weak smell and hard round, irregular or beaded ashes.
Polyester: Polyester has good strength, good wrinkle resistance, low price, static electricity and no irritation to skin.
Near-flame droplet, bubbling in flame, continuous burning, light fragrance, hard round, black or light brown gray, and can be crushed.
Spandex: Spandex is complex, and the distinguishing characteristics of different component contents are subtle.
Determine the proportion of polyester and cotton according to ash content.
Nylon: Polyamide has high strength, better handle than polyester, and high cost performance. Most underwear fabrics are nylon.
Smell, small gray, light brown hard ball.
Cotton: Cotton C is soft to the touch, natural fiber, good hygroscopicity and comfortable to wear.
It burns when it is close to the flame, and there is afterglow after burning. It smells like burning paper, and there is little, soft, black or dark gray ash.