Impregnated nonwovens are made by drying and baking after the fiber mesh is saturated through the adhesive tank and the excess adhesive is squeezed out through a pair of rollers. Because the nonwovens produced by this method are hard to handle, they are only suitable for some garment linings. Foam impregnation is a method of impregnating nonwovens with a foam adhesive. This method is one of the important methods for producing thin and medium - thick nonwovens. Spraying adhesion is the use of compressed air, through a gun, the adhesive will be sprayed on the fiber network. It is mainly suitable for the production of high bulk, porous nonwovens. Such as gush glue cotton, filter material.
thermal bonding method reinforcement: thermal bonding method reinforcement is the main fiber and hot-melt fiber, hot-melt powder or hot-melt film mixed fiber network heating, so that the hot melt material in the fiber network melt, so that the contact between the fiber is fused, and fixed after cooling, so that the fiber network is reinforced into cloth. It includes hot-melt bonding and hot-rolling bonding. Hot-melt bonding process is simple, the main use of drying room for heating and strengthening of the fiber network, can also be used in the heating after the compression roller pressure and reinforcement. Hot-rolling bonding method is to use uniform heating roller to heat and pressurize the fiber net mixed with hot-melt fiber to melt the hot-melt fiber in the rolling area and weld it with the main fiber at the contact point to strengthen the cloth. The method can also be used for auxiliary bonding and calendering of reinforced nonwovens. In addition, thermal bonding reinforcement can also be used as a mechanical reinforcement after the auxiliary reinforcement. At present, the development of the law is on the rise.
Introduction to the production of polymer extruded nonwovens spinning and netting is the most important and widely used method of polymer extruding. In China, the nonwovens produced by this method account for about 30% of the total nonwovens. Spinning into a net method is to use the principle of chemical fiber spinning, using fiber to form a net in the process of polymer spinning, and then the fiber net becomes a nonwoven fabric through self-bonding or mechanical, chemical and thermal reinforcement. The technique of spinning and forming a net by melt spinning includes three key processes: spinning, drawing and forming a net. Due to the advantages of short process flow and high strength and elongation, the spinning net method has a promising future.
Introduction to production of melt-jet nonwovens: firstly, the polymer is melted into a melt, which is sent into an extrusion cavity and extruded through a row of flat spinneret holes. Rapid hot air flow by the pipe import, and from cotton spinning up and down flat on both sides of the slit in the high-speed jet, it has not yet formed the melt trickle dispersion, tensile, form a very fine irregular superfine short fibers, then condensed in porous cylinder or shade net fabric, the fabric become nonwovens by self bonding or hot glue. Melt-blown nonwovens are mainly used as high efficiency air filtration materials, linoleum absorbent, medical and sanitary products, etc. Is a very developed type of nonwovens.
Introduction to wet nonwovens production wet nonwovens is one of the highest speed in the production of nonwovens, it is the fiber suspended in water, and then the suspension slurry transport to the filter screen, because the water flow falls, the fiber evenly spread on the filter screen become fiber network, finally after bonding reinforcement, drying and so on become nonwovens. The production process of wet process is basically similar to that of dry process, which includes four stages: fiber preparation, wet process netting, bonding and reinforcement, and post-treatment.
Preparation of fiber the process is to loosen the fiber raw materials placed in the hydrolytic material into single fibers, and at the same time make the different fiber raw materials fully mix to make the fiber suspension slurry, and then transport the suspension slurry to the mesh-forming mechanism without producing fiber clumps.
Wet netting it is to distribute the fibers to the netting curtain in the wet state. The wet method of netting is divided into oblique netting and circular netting. Its main distinction is the shape that becomes net shade is different, inclined net method is inclined flat shade, circular net method is circular net.
Adhesion reinforcement wet dust into a network of adhesion reinforcement and dry similar, can be used adhesive or hot rolling reinforcement.
Post-processing the post-processing of wet-process nonwovens includes drying, baking, etc., which is similar to dry bonding.
Four. Nonwovens finishing overview nonwovens finishing is mainly to improve the performance of nonwovens, improve the appearance and increase the variety of products. It mainly includes dry finishing and wet finishing. Shrinkage finishing in dry finishing is to increase the tightness and strength of the product. Soft finishing makes the product plump and feels good.
Calendering and embossing finish can keep even thickness of the product and produce concave and convex pattern on the surface of nonwovens. In addition, dry finishing also includes coating finishing, mechanical hole and seam finishing. The wet finishing of nonwovens includes washing, bleaching, dyeing, printing, water repellent finishing, water absorption finishing, dust absorption finishing, flame retardant finishing, antistatic finishing and sanitary finishing.
However, not all nonwovens are finished, depending on the end product's use.