Dual texture absorbent nonwoven web

Abstract

A dual texture coform nonwoven web prepared from meltblown filaments and at least one secondary material is disclosed. The dual texture coform nonwoven web is useful as cleaning pads, wipes, mops, among other articles of manufacture. One surface of the dual texture coform nonwoven web contains coarse filaments, which impart an abrasive characteristic to this surface of the nonwoven web and the other surface contains fine filaments, which impart a non-abrasive or soft surface to the nonwoven web. Also disclosed is the process of producing the dual texture coform nonwoven web, method of using the dual texture coform nonwoven web as a wipe, mop, and the like, along with cleaning kits containing the coform nonwoven web.

We claim:  
     
         1 . A dual texture coform nonwoven web comprising a matrix of thermoplastic meltblown filaments and at least one secondary material, wherein the coform nonwoven web has a first exterior surface and a second exterior surface, the first exterior surface comprises fine thermoplastic meltblown fibers having an average diameter of less than about 15 microns and the secondary material; and the second exterior surface comprises coarse thermoplastic meltblown fibers having an average diameter greater than about 15 microns and the secondary material.  
     
     
         2 . The dual texture coform of  claim 1 , wherein the concentration of the coarse thermoplastic meltblown filaments in the matrix decrease in a direction from the second exterior surface towards the first exterior surface.  
     
     
         3 . The dual texture coform of  claim 2 , wherein the secondary material comprises an absorbent material selected from the group consisting of absorbent particles, absorbent fibers and a mixture of absorbent fibers and absorbent particles.  
     
     
         4 . The dual texture coform of  claim 3 , wherein the absorbent material comprises pulp.  
     
     
         5 . The dual texture coform of  claim 2 , wherein the coarse thermoplastic meltblown filaments have an average fiber diameter in the range above about 15 microns and less than about 39 microns.  
     
     
         6 . The dual texture coform of  claim 5 , wherein the coarse thermoplastic meltblown fibers have an average fiber diameter in the range above about 20 microns and less than about 35 microns.  
     
     
         7 . The dual texture coform of  claim 5 , wherein the secondary material comprises an absorbent material selected from the group consisting of absorbent particles, absorbent fibers and a mixture of absorbent fibers and absorbent particles.  
     
     
         8 . The dual texture coform of  claim 7 , wherein the absorbent material comprises pulp.  
     
     
         9 . The dual texture coform of  claim 3 , wherein the absorbent material comprises between about 20% and about 85% by weight of the coform material.  
     
     
         10 . The dual texture coform of  claim 9 , wherein the absorbent material comprises between about 30% and about 70% by weight of the coform material.  
     
     
         11 . The dual texture coform of  claim 2 , wherein the fine and coarse thermoplastic meltblown filaments independently comprise a polymer selected from the group consisting of polyolefins, polyesters, polyamides, polycarbonates, polyurethanes, polyvinylchloride, polytetrafluoroethylene, polystyrene, polyethylene terephathalate, polylactic acid and copolymers and blends thereof.  
     
     
         12 . The dual texture coform of  claim 11 , wherein the fine and coarse thermoplastic meltblown filaments comprise a polyolefin selected from the group consisting of polyethylene, polypropylene, polybutylene and blends thereof.  
     
     
         13 . The dual texture coform of  claim 3 , wherein the fine and coarse thermoplastic meltblown filaments comprise a polyolefin selected from the group consisting of polyethylene, polypropylene, polybutylene and blends thereof; the coarse thermoplastic meltblown filaments have an average fiber diameter in the range above about 15 microns and less than about 39 microns; the absorbent material comprises pulp and is present in an amount of about 30% to about 70% by weight of the coform material.  
     
     
         14 . The dual texture coform of  claim 13 , wherein the fine and coarse thermoplastic meltblown filaments comprise polypropylene.  
     
     
         15 . A wiper comprising the dual texture coform nonwoven web of  claim 1 .  
     
     
         16 . The wiper of  claim 15 , wherein the wiper is saturated with between about 150 and about 900 weight percent of a liquid, based on the dry weight of the wipe.  
     
     
         17 . A wiper comprising the dual texture coform nonwoven web of  claim 14 .  
     
     
         18 . A mop comprising the dual texture coform nonwoven web of  claim 1 .  
     
     
         19 . The mop of  claim 18 , wherein the mop is saturated with between about 500 and about 900 weight percent of a liquid, based on the dry weight of the mop.  
     
     
         20 . A mop comprising the dual texture coform nonwoven web of  claim 14 .  
     
     
         21 . A dual texture nonwoven web comprising a first surface and a second surface, wherein the first surface comprises a composite matrix comprising fine thermoplastic meltblown filaments having an average diameter of less than about 15 microns and at least one secondary material, and the second surface comprises a composite matrix comprising coarse thermoplastic meltblown fibers having an average diameter greater than about 15 microns and at least one secondary material.  
     
     
         22 . The dual texture nonwoven web of  claim 21 , wherein the coarse thermoplastic meltblown fibers have an average fiber diameter in the range above about 15 microns and less than about 39 microns.  
     
     
         23 . The dual texture nonwoven web of  claim 22 , wherein the coarse thermoplastic meltblown fibers have an average fiber diameter in the range above about 20 microns and less than about 35 microns.  
     
     
         24 . The dual texture nonwoven web of  claim 21 , wherein the secondary material comprises and absorbent material selected from the group consisting of absorbent particles, absorbent fibers and a mixture of absorbent fibers and absorbent particles.  
     
     
         25 . The dual texture nonwoven web of  claim 24 , wherein the absorbent material comprises pulp.  
     
     
         26 . The dual texture nonwoven web of  claim 24 , wherein the absorbent material comprises between about 20% and about 85% by weight of the composite material.  
     
     
         27 . The dual texture nonwoven web of  claim 26 , wherein the absorbent material comprises between about 30% and about 70% by weight of the composite material.  
     
     
         28 . The dual texture nonwoven web of  claim 21 , wherein the fine and coarse thermoplastic meltblown filaments independently comprise a polymer selected from the group consisting of polyolefins, polyesters, polyamides, polycarbonates, polyurethanes, polyvinylchloride, polytetrafluoroethylene, polystyrene, polyethylene terephathalate, polylactic acid and copolymers and blends thereof.  
     
     
         29 . The dual texture nonwoven web of  claim 28 , wherein the fine and coarse thermoplastic meltblown filaments comprise a polyolefin selected from the group consisting of polyethylene, polypropylene, polybutylene and blends thereof.  
     
     
         30 . The dual texture coform of  claim 24 , wherein the fine and coarse thermoplastic meltblown filaments comprise a polyolefin selected from the group consisting of polyethylene, polypropylene, polybutylene and blends thereof; the coarse thermoplastic meltblown filaments have an average fiber diameter in the range above about 15 microns and less than about 39 microns; the absorbent material comprises pulp and is present in an amount of about 30% to about 70% by weight of the coform material.  
     
     
         31 . The dual texture coform nonwoven web of  claim 21 , wherein the first surface further comprises coarse thermoplastic meltblown fibers having an average diameter greater than about 15 microns, and the second surface further comprises fine thermoplastic meltblown filaments having an average diameter of less than about 15 microns.  
     
     
         32 . A wiper comprising the dual texture nonwoven web of  claim 21 .  
     
     
         33 . The wiper of  claim 32 , wherein the wiper is saturated with between about 150 and about 900 weight percent of a liquid, based on the dry weight of the wipe.  
     
     
         34 . A mop comprising the dual texture nonwoven web of  claim 21 .  
     
     
         35 . The mop of  claim 34 , wherein the mop is saturated with between about 500 and about 900 weight percent of a liquid, based on the dry weight of the mop.  
     
     
         36 . A method for preparing a dual texture coform nonwoven web comprising 
 a. providing a first stream of thermoplastic meltblown filaments comprising filaments having an average diameter of less than about 15 microns;    b. providing a second stream of thermoplastic meltblown filaments comprising filaments having an average diameter greater than about 15 microns:    c. converging the first stream of thermoplastic meltblown filaments and the second stream of thermoplastic meltblown filaments in an intersecting relationship to form an impingement zone;    d. introducing a stream of at least one secondary material between the first and second streams of the thermoplastic meltblown filaments at or near the impingement zone to form a composite stream; and    e. depositing the composite stream onto a forming surface as a matrix of meltblown filaments and a secondary material to form a nonwoven web comprising a first and a second exterior surface; the first exterior surface comprises fine thermoplastic meltblown fibers having average diameter of less than about 15 microns and at least one secondary material, and the second exterior surface comprises coarse thermoplastic meltblown fibers having an average diameter greater than about 15 microns and at least one secondary material.    
     
     
         37 . A method for preparing a dual texture coform nonwoven web comprising 
 a. providing a first stream of thermoplastic meltblown filaments;    b. introducing a stream of at least one secondary material to the first stream of thermoplastic meltblown filaments to form a first composite stream;    c. providing a second stream of thermoplastic meltblown filaments;    d. introducing a stream of at least one secondary material to the first stream of thermoplastic meltblown filaments to form a second composite stream;    e. depositing the first composite stream onto a forming surface as a matrix of thermoplastic meltblown filaments and at least one secondary material to form a first deposited layer; and    f. depositing the second composite stream onto the first deposited layer as a matrix of thermoplastic meltblown filaments and at least one secondary material to form a dual texture coform nonwoven web;    wherein one of the first stream of thermoplastic meltblown filaments or the second stream of thermoplastic meltblown filaments comprises thermoplastic meltblown filaments having average diameter of less than about 15 microns and the other of the first stream of thermoplastic meltblown fibers or the second stream of thermoplastic meltblown fibers comprises thermoplastic meltblown filaments having an average diameter greater than about 15 microns.    
     
     
         38 . A cleaning implement comprising: 
 a. a handle;    b. a head; and    c. a removable cleaning sheet;    wherein head is connected to the handle, the removable cleaning sheet is removable attached to the head and the removable cleaning sheet comprises the dual texture nonwoven web of  claim 1 .    
     
     
         39 . A cleaning implement comprising: 
 a. a handle;    b. a head; and    c. a removable cleaning sheet;    wherein head is connected to the handle, the removable cleaning sheet is removable attached to the head and the removable cleaning sheet comprises the dual texture nonwoven web of  claim 21 .    
     
     
         40 . A method of cleaning a surface comprising contacting and wiping the surface with a cleaning sheet comprising the dual texture nonwoven web of  claim 1 .  
     
     
         41 . A method of cleaning a surface comprising contacting and wiping the surface with a cleaning sheet comprising the dual texture nonwoven web of  claim 21 .  
     
     
         42 . A kit comprising the cleaning implement of  claim 38  and a plurality of the dual texture nonwoven webs.  
     
     
         43 . A kit comprising the cleaning implement of  claim 39  and a plurality of the dual texture nonwoven webs.