Non-woven fabric for food-grade packaging and preparation method thereof

Abstract

The present disclosure provides a non-woven fabric, which includes 20% to 50% by weight of one or more plant-based fibers, 30% to 50% by weight of one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C., and 10% to 30% by weight of one or more water-based binders. The non-woven fabric uses low-melting point thermoplastic fibers or thermoplastic bicomponent fibers, which ensures a low heat-sealing temperature while maintaining heat-sealing strength. The low binder content addresses the adhesion issue during the processing of non-woven fabric and reduces production energy consumption. By optimizing the ratio of each component, various key properties are balanced. In addition to excellent heat-sealing properties, the non-woven fabric also exhibits good processing properties, mechanical properties, and hydrophilic properties. The fabric surface is free of adhesion and has excellent technical effects in dry and wet stiffness, hygroscopicity, and roughness.

What is claimed is: 
     
         1 . A non-woven fabric, comprising:
 20% to 50% by weight of one or more plant-based fibers;   30% to 50% by weight of one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C.; and   10% to 30% by weight of one or more water-based binders.   
     
     
         2 . The non-woven fabric of  claim 1 , comprising:
 25% to 45% by weight of one or more plant-based fibers;   35% to 45% by weight of one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C.; and   15% to 25% by weight of one or more water-based binders.   
     
     
         3 . The non-woven fabric of  claim 1 , further comprising other thermoplastic fiber(s). 
     
     
         4 . The non-woven fabric of  claim 3 , wherein the non-woven fabric consists of one or more plant-based fibers, one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C., other thermoplastic fiber(s), and one or more water-based binders, with a total content of all components being 100% by weight. 
     
     
         5 . The non-woven fabric of  claim 1 , wherein the non-woven fabric consists of one or more plant-based fibers, one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C., and one or more water-based binders, with a total content of all components being 100% by weight. 
     
     
         6 . The non-woven fabric of  claim 1 , wherein the non-woven fabric consists of 35% by weight of one or more plant-based fibers, 40% by weight of one or more low-melting point thermoplastic fibers or thermoplastic bicomponent fibers with a melting point below 180° C., and 25% by weight of one or more water-based binders. 
     
     
         7 . The non-woven fabric of  claim 1 , wherein the low-melting point thermoplastic fiber or thermoplastic bicomponent fiber is selected from a group consisting of PE, PP, PLA, LPET, PE/PET, LPET/PET, PE/PP, and PE/PLA. 
     
     
         8 . The non-woven fabric of  claim 1 , wherein the low-melting point thermoplastic fiber or thermoplastic bicomponent fiber is selected from a group consisting of PE/PET, and LPET/PET. 
     
     
         9 . The non-woven fabric of  claim 1 , wherein the plant-based fiber is selected from a group consisting of natural plant-based fibers or regenerated plant-based fibers. 
     
     
         10 . The non-woven fabric of  claim 1 , wherein the plant-based fiber is selected from a group consisting of viscose fibers, lyocell fibers, bamboo fibers, hemp fibers, wood fibers, and cotton fibers. 
     
     
         11 . The non-woven fabric of  claim 1 , wherein the plant-based fiber is selected from a group consisting of viscose fibers, bamboo fibers, and hemp fibers. 
     
     
         12 . The non-woven fabric of  claim 1 , wherein the water-based binder is selected from a group consisting of vinyl acetate-ethylene copolymers, acrylates, polyurethanes, polylactic acid (PLA), polybutylene succinate (PBS), polyhydroxyalkanoates (PHA), vinyl acetate copolymers, vinyl acrylic copolymers, and styrene-butadiene copolymers. 
     
     
         13 . The non-woven fabric of  claim 1 , wherein the water-based binder is selected from a group consisting of vinyl acetate-ethylene copolymers and acrylates. 
     
     
         14 . A bagged product comprising a bag formed from the non-woven fabric of  claim 1  and a product in the bag. 
     
     
         15 . The bagged product of  claim 14 , wherein the product in the bag is food or traditional Chinese medicine. 
     
     
         16 . A method for preparing a non-woven fabric, wherein according to the composition requirements of the non-woven fabric of  claim 1 , the method comprises the following steps which are performed sequentially: fiber bale unpacking, opening, metering and mixing of fibers, pre-carding, cross lapping, primary carding, longitudinal lapping, web edge trimming, foaming, foam binder application, and drying; and optionally comprising a final winding step. 
     
     
         17 . The method of  claim 16 , wherein a defect inspection step is further included between the drying and the winding.