Non-woven wet wiping

Abstract

A non-woven wet wipe product ( 22 ) comprising a sheet member, for use with a wet wiping agent ( 32 ), ( 18 ), the product comprising a segment of a non-woven self-supporting web ( 150 ) comprised of an assemblage of fibers including synthetic thermoplastic fibers and absorbent or adsorbent fibers, the non-woven web ( 150 ) being in a permanent, dry-creped, heat-set condition defining a succession of ridges ( 24 ) and grooves ( 26 ) in the overall body ( 30 ) of the web, the constituent thermoplastic fibers of the sheet member having been heat-set simultaneously during the imparting of the ridges and grooves to the web, the heat-set condition of the dry-creped thermoplastic fibers preserving the ridge and groove configuration during prolonged presence in the web of the wet agent ( 32 ). The wet wiping agent can be initially, prewet in the packaging, with liquid disposed through the body and on the surface of the dry-creped, heat-set sheet-form member and its constituent fibers. In this case, the product is packaged in a stack within a liquid tight container. In another case the wipes are packaged dry to be wet by the user. Methods for making the products are also disclosed. Whereas advantageous embodiments are formed by hydro entanglement, other embodiments are formed using other non-woven forming processes, including wet-laid techniques, etc.

What is claimed is:  
     
         1 . A non-woven wet wipe product ( 22 ) comprising a sheet member, pre-wetted with a wet wiping agent ( 16 ), and disposed in a fluid-proof package ( 18 ), the product comprising: 
 a. a segment of a non-woven self-supporting web ( 11 ,  120 ,  150 ) comprised of an assemblage of hydroentangled fibers ( 8 ,  9 ) including synthetic thermoplastic strength-providing fibers ( 8 ) and absorbent or adsorbent fibers ( 9 ),    b. the non-woven web ( 14 ) being in a permanent, dry-creped, heat-set condition defining a succession of ridges ( 24 ) and grooves ( 26 ) in the overall body ( 30 ) of the web, the constituent thermoplastic fibers ( 8 ) of the sheet member having been heat-set simultaneously during the imparting of the ridges and grooves to the web, the heat-set condition of the dry-creped thermoplastic fibers preserving the ridge and groove configuration during prolonged presence in the web of the wet agent ( 16 ),    c. the wet wiping agent ( 16 ) being disposed through the body ( 30 ) and on the surface of the dry-creped, heat-set sheet-form member and its constituent fibers ( 8 ,  9 ).    
     
     
         2 . A non-woven wet wipe product ( 22 ) comprising an adsorbent sheet member adapted to be wetted with a wet wiping agent, the product comprising: 
 a. a segment of a non-woven self-supporting web ( 11 ,  120 ,  150 ) comprised of an assemblage of fibers ( 8 ,  9 ), that includes synthetic thermoplastic fibers ( 8 ),    b. the non-woven web ( 14 ) being in a permanent, dry-creped, heat-set, volume-enhanced condition, the constituent thermoplastic fibers ( 8 ) of the sheet member having been heat-set simultaneously during the creping of the web, the heat-set condition of the dry-creped thermoplastic fibers preserving the volume-enhanced structure of the assemblage during prolonged presence in the web of the wet agent ( 16 ),    
     
     
         3 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the sheet has been coarsely dry-creped, resulting in a coarse distribution of ridge formations ( 24 ) in the sheet.  
     
     
         4 . The wet wipe product of  claim 1  or  2  in which there are between about 8 and 25 heat-set ridges ( 24 ) per lineal inch of the web (between about 3.1 and 9.8 ridges per linear cm).  
     
     
         5 . The wet wipe product ( 22 ) of  claim 1  or  2  in which there are between about 8 and 15 heat-set ridges ( 24 ) per lineal inch of the web (between about 3.1 and 5.9 ridges per lineal cm).  
     
     
         6 . The wet wipe product ( 22 ) of  claim 1  or  2  in which there are between about 15 and 20 heat-set ridges ( 24 ) per lineal inch of the web (between about 5.9 and 7.9 ridges per lineal cm).  
     
     
         7 . The wet wipe product ( 22 ) of  claim 1  or  2  in which there are between about 20 and 25 heat-set ridges ( 24 ) per lineal inch of the web (between about 7.9 and 9.8 ridges per lineal cm).  
     
     
         8 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the sheet member is comprised of between about ⅓ and ⅔ by weight absorbent or adsorbent fibers ( 9 ) and between about ⅓ and ⅔ by weight of synthetic thermoplastic, strength-imparting fibers ( 8 ).  
     
     
         9 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the sheet member comprises about equal weight of the absorbent or adsorbent fibers and the thermoplastic, strength-imparting fibers ( 8 ).  
     
     
         10 . A wet wipe product of  claim 1  or  2  in which the sheet member comprises absorbent fibers that are strength members.  
     
     
         11 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the thermoplastic fibers ( 8 ) comprise PET (polyester).  
     
     
         12 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the thermoplastic fibers ( 8 ) comprise polypropylene.  
     
     
         13 . The wet wipe product of  claim 1  or  2  in which the thermoplastic fibers are polyethylene.  
     
     
         14 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the absorbent or adsorbent fibers ( 9 ) are cellulosic.  
     
     
         15 . The wet wipe product ( 22 ) of  claim 14  in which the cellulosic fibers comprise natural fibers.  
     
     
         16 . The wet wipe product of  claim 1  or  2  in which all of the fibers are thermoplastic.  
     
     
         17 . The wet wipe product ( 22 ) of  claim 1  or  2  in which absorbent or adsorbent fibers comprise rayon.  
     
     
         18 . The wet wipe product ( 22 ) of  claim 1  or  2  comprising fibers ( 8 ) of PET and fibers ( 9 ) of wood pulp.  
     
     
         19 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the web ( 11 ,  120 ,  150 ) comprises a spunlace web ( 120 ).  
     
     
         20 . The wet wipe product ( 22 ) of  claim 1  or  2  in which the wet wiping agent ( 16 ) comprises an aqueous agent.  
     
     
         21 . The wet wipe product ( 22 ) of  claim 20  in which the wet wiping agent ( 16 ) comprises one of a soap, a detergent, a solvent, a cleaning, a window washing, a sanitizing, a biociding, a polishing, an abrading and a neutralizing agent.  
     
     
         22 . The wet wipe product ( 22 ) of  claim 20  in which the wet wiping agent ( 16 ) comprises one of an insect repellant, a paint solvent, a paint remover, a finish remover, an oil solvent, a grease solvent, a cosmetic remover, a makeup remover, a stain remover, a stain, a paint, a varnish, a wax and a polish.  
     
     
         23 . A package ( 18 ) comprising a face-to-face stack ( 21 ) of a plurality of sheet members ( 22 ), each sheet member comprising: 
 a. a segment of a non-woven self-supporting web ( 11 ,  120 ,  150 ) comprised of an assemblage of hydroentangled fibers ( 8 ,  9 ) including synthetic thermoplastic strength-providing fibers ( 8 ) and absorbent or adsorbent fibers ( 9 ),    b. the non-woven web ( 14 ) being in a permanent, dry-creped, heat-set condition defining a succession of ridges ( 24 ) and grooves ( 26 ) in the overall body ( 30 ) of the web, the constituent thermoplastic fibers ( 8 ) of the sheet member having been heat-set simultaneously during the imparting of the ridges ( 24 ) and grooves ( 26 ) to the web, the heat-set condition of the dry-creped thermoplastic fibers ( 8 ) preserving the ridge ( 24 ) and groove ( 26 ) configuration during prolonged presence in the web of the wet agent ( 16 ),    c. the wet wiping agent ( 16 ) being disposed through the body and on the surface of the dry-creped, heat-set sheet-form member and its constituent fibers ( 8 ,  9 ).    
     
     
         24 . A package ( 18 ) comprising a face-to-face stack ( 21 ) of a plurality of sheet members ( 22 ), each sheet member comprising: 
 a. a segment of a non-woven self-supporting web ( 11 ,  120 ,  150 ) comprised of an assemblage of fibers ( 8 ,  9 ) including synthetic thermoplastic fibers ( 8 )    b. the non-woven web ( 14 ) being in a permanent, dry-creped, heat-set volume-enhanced condition, the constituent thermoplastic fibers ( 8 ) of the sheet member having been heat-set simultaneously during the imparting of ridges ( 24 ) and grooves ( 26 ) to the web, the heat-set condition of the dry-creped thermoplastic fibers ( 8 ) capable of preserving the enhanced volume structure of the assemblage during prolonged presence in the web of the wet agent ( 16 ).    
     
     
         25 . A method of producing a wet wipe product ( 22 ) comprising: 
 a. providing a self-supporting non-woven assemblage ( 11 ,  150 ) of hydroentangled fibers ( 8 ,  9 ) including synthetic thermoplastic strength-providing fibers ( 8 ) and absorbent or adsorbent fibers ( 9 ),    b. passing the non-woven assemblage ( 11 ,  120 ,  150 ) through a dry-creping machine ( 149 ) to impart ridges and grooves to a body ( 30 ) of the assemblage while simultaneously heating the assemblage to a temperature above the temperature required to heat-set the thermoplastic fibers ( 8 ), and    c. thereafter sizing the assemblage into a wipe member ( 22 ), pre-applying a wet wiping agent ( 16 ) so that the wet wiping agent is disposed through the body ( 30 ) and on the surface of the dry-creped sheet-form member and its constituent fibers ( 8 ,  9 ), and sealing the wipe member in a fluid-tight package ( 18 ).    
     
     
         26 . A method of producing a wet wipe product ( 22 ) comprising: 
 a. providing a self-supporting non-woven sorbent assemblage ( 11 ,  150 ) of fibers ( 8 ,  9 ) including synthetic fibers ( 8 ),    b. passing the non-woven assemblage ( 11 ,  120 ,  150 ) through a dry-creping machine ( 149 ) to impart ridges and grooves to a body ( 30 ) of the assemblage while simultaneously heating the assemblage to a heat set temperature to heat-set the thermoplastic fibers ( 8 ) to thereby enhance the sorbent volume structure of the assemblage, and    c. thereafter sizing the assemblage into a wipe member ( 22 ).    
     
     
         27 . The method of  claim 20  or  21  in which the dry-creping is performed under conditions to produce coarse dry-crepe.  
     
     
         28 . The method of  claim 27  comprising employing a spunlace process for providing the nonwoven assemblage ( 11 ,  150 ).  
     
     
         29 . The method of  claim 27  in which the assemblage ( 11 ,  120 ,  150 ) is formed by providing a carded web of polyester fibers ( 8 ) introducing a layer of wood pulp ( 9 ) to the carded web, and subjecting the layer of wood pulp and carded web to hydroentanglement followed by dewatering and drying prior to dry-creping.  
     
     
         30 . The method of  claim 27  comprising conducting the dry-creping step with a bladed drycreper comprising a driven roll ( 152 ), a pressing surface ( 154 ,  155 ) pressing the fiber assemblage ( 150 ) against the driven roll sufficiently to cause the fiber assemblage to be advanced forward, and opposing the advance of the assemblage in the direction of the plane of the assemblage with a retarder blade ( 156 ), a tip of which is held adjacent the driven roll, at least one surface of the drycreper being heated to heat the thermoplastic fiber constituent to heat-set temperature of the thermoplastic fibers.  
     
     
         31 . The method of  claim 30  in which sorbent fibers ( 9 ) in the assemblage comprise wood pulp fibers, the fiber assemblage is substantially free of thermoplastic binder, and the dry-creping is conducted in a manner leaving the wood pulp fibers substantially permanently uncompressed in the direction of the thickness of the assemblage.  
     
     
         32 . The method of  claim 30  in which the thermoplastic fibers ( 8 ) include PET (polyester) and said surface of the drycreper ( 149 ) is heated to a temperature above 250° F. sufficient to set the thermoplastic fibers.  
     
     
         33 . The method of  claim 31  in which the pressing surface ( 154 ,  155 ) is so heated.  
     
     
         34 . The method of  claim 32  in which the driven roll ( 152 ) is so heated.  
     
     
         35 . The method of  claim 31  in which the driven roll ( 152 ) is so heated.  
     
     
         36 . The method of  claim 30  in which the dry-creping and simultaneous heat setting is carried out under conditions in which the absorbent or adsorbent fibers ( 9 ) are substantially uncompressed in a direction of thickness of the web ( 11 ,  120 ,  150 ) during formation of the dry-crepe.  
     
     
         37 . The method of  claim 30  in which the driven roll ( 152 ) of the drycreper includes a continuous cylinder, the roll being equipped with an internal heater (H′).  
     
     
         38 . The method of  claim 37 , wherein the internal heater (H′) comprises an electric resistance heater.  
     
     
         39 . The method of  claim 37 , wherein the internal heater (H′) comprises heat exchange passages containing a hot fluid.  
     
     
         40 . The method of  claim 39 , wherein the hot fluid is one of hot water, steam, hot gas, hot air, combustion gas or oil.  
     
     
         41 . The method of  claim 31  in which the dry-creping and simultaneous heat-setting is conducted in a manner to shorten the web ( 11 ,  150 ) at least 4%, increasing a bulk thickness of the sheet member.  
     
     
         42 . The method of  claim 41  in which the dry-creping and simultaneous heat-setting is conducted in a manner to shorten the web ( 11 ,  120 ,  150 ) within the range between about 4 to 25%.  
     
     
         43 . The method of  claim 41  in which the dry-creping and simultaneous heat-setting is conducted in a manner to shorten the web ( 11 ,  120 ,  150 ) within the range between about 4 and 12%.  
     
     
         44 . The method of  claim 41  in which the dry-creping and simultaneous heat-setting is conducted in a manner to shorten the web ( 11 ,  120 ,  150 ) within the range between about 4 and 8%.  
     
     
         45 . The method of  claim 30 , in which a plurality of said sheet members ( 22 ), in a stack ( 21 ) in face-to-face contact, are packaged wet in a fluid tight container ( 18 ).  
     
     
         46 . The method of  claim 45  including adding to the sheet members ( 22 ) before completing the packaging one of a soap, a detergent, a solvent, a cleaning, a window washing, a sanitizing, a biociding, a polishing, an abrading and a neutralizing agent.  
     
     
         47 . The method of  claim 45  including adding to the sheet members ( 22 ) before completing the packaging one of an insect repellant, a paint solvent, a paint remover, a finish remover, an oil solvent, a grease solvent, a cosmetic remover, a makeup remover, a stain remover, a stain, a paint, a varnish, a wax and a polish.  
     
     
         48 . The wet wipe product of  claim 1  or  2  or the method of  claim 26  wherein the fiber content of said nonwoven assemblage comprises at least 20% by weight thermoplastic synthetic fibers.  
     
     
         49 . The subject of  claim 48  in which the web is contacted with a surface heated between about 250° F. to 425° F. to heat set the thermoplastic fibers.  
     
     
         50 . The subject of  claim 49  in which the thermoplastic fibers are polypropylene and the temperature of the surface is between 250 and 300° F., preferably about 270F.  
     
     
         51 . The subject of  claim 49  in which the thermoplastic fibers are polyester and the temperature of the surface is between about 350 and 450° F., preferably about 365F.  
     
     
         52 . The non-woven wet wipe product of  claim 2 , the package of  claim 24  or the method of  claim 26  in which the nonwoven web comprises a web formed at least in part by entanglement, bonding or adhering.  
     
     
         53 . The subject of  claim 52  in which the web has been formed at least in part by the process of thermal bonding, chemical bonding, spunbonding, meltblowing, caustic entangling, hydraulically aperturing, hydro-entangling, wet laying, or papermaking.