Water-soluble unbleached bag paper, and paper bag

Abstract

In a water-soluble unbleached bag paper comprising lignin-containing cellulose fibers as main component and one or more additive(s), at least one surfactant is contained as additive, and the bag paper has a relative wet strength of less than 6% after a 5-minute wetting time. Furthermore, a paper bag comprised of water-soluble unbleached bag paper is described.

1 . A water-soluble unbleached bag paper comprising lignin-containing cellulose fibers as main component and one or more additive(s), characterized in that at least one surfactant is contained as said additive, that the cellulose fibers are used as oxidatively treated unbleached softwood fibers, and that the bag paper has a relative wet strength of less than 6% after a 5-minute wetting time. 
     
     
         2 . A bag paper according to  claim 1 , characterized in that between 0.1% and 2% surfactant is contained. 
     
     
         3 . A bag paper according to  claim 1  or  2 , characterized in that the at least one surfactant is selected from the group of non-ionic, anionic, cationic or amphoteric surfactants, fatty alcohols, fatty alcohol polylglycol ethers, fatty alcohol sulfates, fatty alcohol, ether sulfates, methyl ether sulfates, fatty alcohol ethoxylates or phenol ethoxylates. 
     
     
         4 . A bag paper according to  claim 1 ,  2  or  3  characterized in that it shows a absorbency corresponding to a K-value of more than 5000. 
     
     
         5 . A bag paper according to any one of  claims 1  to  4 , characterized in that a dry-strength agent is additionally contained. 
     
     
         6 . A bag paper according to any one of  claims 1  to  5 , characterized in that the dry-strength agent is selected from starches like cationic potato starch, corn starch, tapioca starch. 
     
     
         7 . A bag paper according to any one of  claims 1  to  6 , characterized in that the cellulose fibers are used as oxidatively treated, unbleached softwood fibers. 
     
     
         8 . A bag paper according to  claim 7 , characterized in that the cellulose fibers are selected from softwood fibers from conifers, in particular fibers from spruce wood and/or pinewood. 
     
     
         9 . A bag paper according to any one of  claims 1  to  8 , characterized in that the softwood fibers are used as high-consistency-beaten (HC-beaten) and/or low-consistency-beaten (LC-beaten) softwood fibers. 
     
     
         10 . A bag paper according to any one of  claims 1  to  9 , characterized in that the longitudinal/transverse ratio of the tensile strength is between 1 and 1.8, in particular 1.3. 
     
     
         11 . A bag paper according to any one of  claims 1  to  10 , characterized in that the cellulose fibers are contained as dried, in particular flake-dried, pulp. 
     
     
         12 . A paper bag comprised of the water-soluble unbleached bag paper according to any one of  claims 1  to  11 , characterized in that the bag paper is glued with an adhesive, in particular a maltodextrin adhesive. 
     
     
         13 . A paper bag according to  claim 12 , characterized in that it is comprised of a multi-ply bag paper. 
     
     
         14 . A paper bag according to  claim 12  or  13 , characterized in that a layer of water-soluble polymers such as PVA or PE is applied on at least one paper ply.