1. Hand visual inspection method: This method is suitable for non-woven fabric raw materials in loose fiber state.
(1) Cotton fiber is shorter and thinner than ramie fiber and other hemp fiber and wool fiber, often with various impurities and defects.
(2) The hemp fiber feels rough and hard.
(3) The wool fiber is curly and elastic.
(4) Silk is long and slender, with special luster.
(5) Among chemical fibers, only viscose fiber has a large difference in strength between dry and wet states.
(6) Spandex yarn has very large elasticity, and its length can be stretched to more than five times at room temperature.
2. Microscope observation method: It is to identify the non-woven fiber according to the longitudinal and cross-sectional morphological characteristics of the fiber.
(1) Cotton fiber: cross-sectional shape: round waist with mid-waist; longitudinal shape: flat ribbon shape with natural twist.
(2) Hemp (ramie, flax, jute) fiber: cross-sectional shape: round or polygonal waist, with a middle cavity; longitudinal shape: horizontal nodes, vertical lines.
(3) Wool fiber: cross-sectional shape: round or approximately round, some with pith; longitudinal shape: scales on the surface.
(4) Rabbit hair fiber: cross-sectional shape: dumbbell-shaped with hair pith; longitudinal shape: scales on the surface.
(5) Mulberry silk fiber: cross-sectional shape: irregular triangle; longitudinal shape: smooth and straight, with stripes longitudinally.
(6) Ordinary viscose fiber: cross-sectional shape: zigzag, skin-core structure; longitudinal shape: longitudinal grooves.
(7) Rich and strong fiber: cross-sectional shape: less tooth shape, or round or elliptical; longitudinal shape: smooth surface.
(8) Acetate fiber: cross-sectional shape: trilobal or irregular zigzag shape; longitudinal shape: longitudinal stripes on the surface.
(9) Acrylic fiber: cross-sectional shape: round, dumbbell or leaf shape; longitudinal shape: smooth or striped surface.
(10) Chlorine fiber: cross-sectional shape: close to circular; longitudinal shape: smooth surface.
