Pulp-containing biodegradable non-woven fabric and method for producing the same

Abstract

The present invention relates to a biodegradable non-woven fabric, a method for producing a biodegradable non-woven fabric and a wipe or tissue. The biodegradable non-woven fabric comprises biodegradable fibers and pulp fibers. At least a part of the biodegradable fibers is entangled with each other. At least a part of the pulp fibers is covalently bonded to each other by at least one of the group consisting of a biodegradable binder, a biodegradable wet-strength agent and a biodegradable binder fiber.

1 . A biodegradable non-woven fabric comprising biodegradable fibers and pulp fibers,
 wherein at least a part of the biodegradable fibers is entangled with each other, and   at least a part of the pulp fibers is covalently bonded to each other by at least one of the group consisting of a biodegradable binder, a biodegradable wet-strength agent and a biodegradable binder fiber.   
     
     
         2 . The biodegradable non-woven fabric according to  claim 1 , wherein substantially all fibers comprised in the biodegradable non-woven fabric are the biodegradable fibers, the pulp fibers and optionally the biodegradable binder fiber. 
     
     
         3 . The biodegradable non-woven fabric according to  claim 1 , wherein the biodegradable fibers comprise cellulosic fibers, in particular regenerated cellulose fibers. 
     
     
         4 . The biodegradable non-woven fabric according to  claim 3 , wherein the regenerated cellulose fibers are selected from the group consisting of viscose or lyocell. 
     
     
         5 . The biodegradable non-woven fabric according to  claim 1 , wherein the pulp fibers are comprised in an amount of from 20 to 90 wt.-% based on the total weight of the non-woven fabric, and/or wherein the biodegradable fibers are comprised in an amount of from 10 to 80 wt.-% based on the total weight of the non-woven fabric. 
     
     
         6 . The biodegradable non-woven fabric according to  claim 1 , wherein at least a part of the pulp fibers is bonded to each other by a biodegradable binder fiber, in particular wherein the biodegradable binder fiber comprises a bicomponent fiber. 
     
     
         7 . The biodegradable non-woven fabric according to  claim 1 , wherein at least a part of the pulp fibers is bonded to each other by a biodegradable wet-strength agent, in particular wherein the biodegradable wet-strength agent is selected from the group consisting of chitosan, modified starch and cellulose derivatives. 
     
     
         8 . The biodegradable non-woven fabric according to  claim 1 , wherein at least a part of the pulp fibers is bonded to each other by a biodegradable binder, in particular wherein the biodegradable binder is selected from the group consisting of chitosan, modified starch, cellulose derivatives, in particular blends of carboxymethylcellulose and citric acid, and protein based binders, such as casein. 
     
     
         9 . The biodegradable non-woven fabric according to  claim 8 , wherein the biodegradable binder further comprises an additive, such as glycerol, acting as softening agent and/or improving the flexibility and drapability of the non-woven fabric. 
     
     
         10 . The biodegradable non-woven fabric according to  claim 1 , showing an increase of material resiliency characterized by a Circular Bend Stiffness Force determined in accordance with modified ASTM D 4032-94 as described in the specification of more than 25%, preferably more than 50% and most preferably more than 75%, compared to a non-woven fabric without any one of a biodegradable binder fiber, a biodegradable wet-strength agent and a biodegradable binder. 
     
     
         11 . A method for producing a biodegradable non-woven fabric, comprising the steps of:
 (a) forming a fibrous web from a fiber blend comprising biodegradable fibers and pulp fibers or forming a layer of biodegradable fibers with a layer of tissue;   (b) entangling at least a part of the biodegradable fibers with each other by subjecting the fibrous web or the fibrous web combined with a tissue layer to a water-jet treatment; and   (c) drying the entangled fibrous web,   
       wherein the method further comprises at least one of the following steps:
 applying a biodegradable binder to the entangled fibrous web prior to drying the entangled fibrous web, 
 adding a biodegradable wet-strength agent to the fiber blend, 
 blending a biodegradable binder fiber to the fiber blend. 
 
     
     
         12 . The method according to  claim 11 , wherein in step (a) the fibrous web is formed by a wet-laid process or an air-laid process or the fibrous web combined with a tissue layer is formed by a dry laying process such as carding or air-laid. 
     
     
         13 . A biodegradable non-woven fabric obtainable by a method according to  claim 11 . 
     
     
         14 . A wipe or tissue comprising or consisting of the biodegradable non-woven fabric according to  claim 1 . 
     
     
         15 . The wipe or tissue according to  claim 14 ,
 wherein the wipe or tissue is a dry wipe or a wet wipe and/or   wherein the wipe or tissue is selected from the group consisting of facial wipes, cosmetic wipes, baby wipes, sanitary wipes, kitchen tissue, paper towel, handkerchiefs, cleaning tissue, cleansing tissue, floor mop and hard surface cleaning wipe.   
     
     
         16 . Use of a biodegradable binder, a biodegradable wet-strength agent and/or a biodegradable binder fiber for imparting resiliency to a wipe or tissue comprising a biodegradable non-woven fabric.