Abstract:
A containment package for presaturated wiper sheets including a substantially liquid and vapor impermeable body having an interior adapted to receive and store a plurality of wiper sheets presaturated with a solution subject to evaporation. The body includes an access opening adapted for insertion and withdrawal of the wiper sheets through the access opening. At least a first sealing element defining a magnet is supported on a first support structure at a position outside of the interior. At least a second sealing element with magnetic attraction to the first sealing element is disposed on a second support structure at a position outside of the interior.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of, and priority from U.S. provisional application 61/514,582 filed Aug. 3, 2011 the contents of which are hereby incorporated by reference in their entirety as if fully set forth herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure is directed generally to a packaging arrangement for presaturated cleaning wipes and more specifically to a cleaning wipe package incorporating a liquid impermeable containment structure having a resealable opening incorporating one or more magnetic strips disposed adjacent to the perimeter of the opening for use in selectively sealing the opening thereby guarding against evaporation of solvent or other agents used to presaturate the cleaning wipes. 
       BACKGROUND OF THE INVENTION 
       [0003]    Cleaning wipes of textile constructions are known. Such wipes may be presaturated with a solvent or other cleaning agent and stored within an appropriate package. Such packages may be in the form of a flexible envelope container which may be opened to gain access to the enclosed wipes. Wipe packages also may be in the form of a relatively shallow tray with a removable surface covering or lid. 
         [0004]    During use, the interior of wipe packages may be accessed multiple times by a user through a mouth opening as individual wipes are retrieved. By closing the container between uses, evaporation of solvent or other cleaning agents can be reduced. By way of example only, one such prior resealable package is illustrated and described in U.S. Pat. No. 6,978,889 the contents of which are incorporated by reference in their entirety. While such systems may work well, the adhesion force of the releasable adhesive may diminish after multiple uses. Thus, there is a continuing need for an improved sealing system for a pliable storage container. 
       SUMMARY OF THE INVENTION 
       [0005]    The present disclosure provides advantages and alternatives over past wiper sheet packaging systems by providing a containment package for wipes presaturated with a solution subject to evaporation. The containment package incorporates an access opening with at least one pair of opposing magnetically attracted strips adapted to selectively seal the access opening to reduce or prevent evaporation of the solution in the sealed condition. 
         [0006]    In accordance with one exemplary practice, the present disclosure provides a containment package for presaturated wiper sheets including a liquid and vapor impermeable body having an interior adapted to receive and store a plurality of wiper sheets presaturated with a solution subject to evaporation. The body includes an access opening adapted for insertion and withdrawal of the wiper sheets through the access opening. At least a first sealing element defining a magnet is supported on a first support structure at a position outside of the interior. At least a second sealing element of magnetized or non-magnetized character having a complementary magnetic attraction to the first sealing element is disposed on a second support structure at a position outside of the interior. The second support structure is selectively moveable relative to the first support structure to open and close the access opening such that when the first support structure disposed in contacting, opposing relation to the second support structure, the first sealing element and the second sealing element will act through the first support structure and the second support structure to cooperatively form a magnetic seal so as to reversibly seal the access opening in a closed condition. A method of packaging presaturated wiper sheets is also provided. 
         [0007]    Other features and advantages of the disclosure will become apparent to those of skill in the art upon review of the following detailed description, claims and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is schematic perspective view of a pliable containment envelope construction adapted to hold presaturated wiper sheets showing the envelope in an open condition; 
           [0009]      FIG. 2  is a schematic cross-section taken generally along line  2 - 2  in  FIG. 1  with the envelope in a closed condition; 
           [0010]      FIG. 3  is a schematic plan view of an exemplary material blank which may be used to form an exemplary packaging envelope as shown in  FIGS. 1 and 2 ; 
           [0011]      FIG. 4  is a schematic perspective view of a packaging tray adapted to hold presaturated wiper sheets showing the packaging container in a closed condition; and 
           [0012]      FIG. 5  is a schematic cross-section taken generally along line  5 - 5  in  FIG. 4 . 
       
    
    
       [0013]    While the invention has been illustrated and will hereafter be described in connection with certain exemplary and potentially preferred embodiments, practices and procedures, it is to be understood that the invention is in no way limited to any such illustrated and described embodiments practices and procedures. Rather, it is to be understood that it is the intention of the applicant to cover all alternatives and modifications as may fall broadly within the spirit and scope of the invention. 
       DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0014]    Reference will now be made to the drawings wherein to the extent possible like reference numbers are utilized to designate like elements throughout the various views. Looking jointly to  FIGS. 1 and 3 , there is illustrated an exemplary package for a multiplicity of wiper sheets  10  which may be of either a single ply or multi-ply construction. By way of example only, it is contemplated that the wiper sheets  10  may be formed from a woven, knit or non-woven absorbent textile material which has been pre-saturated with a solvent or other cleaning agent. The wiper sheets have sufficient pliability to permit folding. 
         [0015]    In the embodiment of  FIGS. 1 and 2 , the wiper sheets  10  are stored within a pliable containment envelope  12  of foil laminate or other material as will be known to those of skill in the art defining an envelope body which is substantially impermeable to liquid and gas transmission. The containment envelope  12  includes a resealable mouth opening  14  (also referred to as a pouch opening or access opening) with a first boundary edge  16  and a second boundary edge  18  at the top of deformable walls oriented in opposing relation substantially along the length of the mouth opening  14 . As best seen in  FIG. 2 , the first boundary edge  16  and the second boundary edge  18  each may be formed by folding the containment envelope material forming the deformable walls over upon itself to establish a double layer cuff construction with a pocket between the layers outboard from the mouth opening. 
         [0016]    Referring now to  FIG. 2 , in the illustrated exemplary arrangement, a first sealing element  20  in the form of a magnetic strip may be disposed in substantially covered, contained relation within the pocket below the first boundary edge  16 . A second sealing element  22  in the form of a magnetic strip or non-magnetized metal or other material which is magnetically attracted to the first sealing element  20  may be disposed in substantially covered, contained relation within the pocket below the second boundary edge  18 . The sealing elements  20 ,  22  thus cooperatively form an operative magnetic seal which preferably extends substantially continuously along the entire length of the mouth opening  14 . While the complementary sealing elements  20 ,  22  are illustrated as extending to an elevation corresponding substantially to the interior of the boundary edges  16 ,  18  it will be understood that in practice the magnetic strips may occupy any opposing elevation positions as may be desired within the pockets below the boundary edges. 
         [0017]    As shown, the pockets containing the first sealing element  20  and second sealing element  22  may be closed if desired. By way of example only, the folded over portion of the envelope material may be adhesively bonded or heat sealed to a portion of the envelope body at an elevation below the sealing elements  20 ,  22  to form a surface seal  24 . If desired, such a surface seal  24  may extend continuously or intermittently about the perimeter of the containment envelope  12 . Regardless of whether or not a surface seal is formed, the sealing elements  20 ,  22  preferably will be substantially covered on the exterior by the folded over portions of the envelope material such that the sealing elements  20 ,  22  are not visible and do not form an outer contact surface for the containment envelope  12 . Thus, the sealing elements  20 ,  22  will be substantially isolated from other surfaces in the environment of use. This isolation of the sealing elements may be beneficial in maintaining their integrity as well as in avoiding any potential contamination to outside surfaces from the material forming the sealing elements. In the illustrated exemplary construction, each of the sealing elements  20 ,  22  is also isolated from the interior of the containment envelope  12 . Thus, in practice, the wiper sheets  10  are never in physical contact with the material forming the sealing elements  20 ,  22 . Accordingly, any potential for contamination by the sealing elements is avoided. 
         [0018]    By way of example only, and not limitation, at least the first sealing element  20  may be formed from a suitable, magnetized material of pliable character and defined polarity such as polymeric ferrous oxide or the like. In one exemplary practice, the second sealing element  22  may be formed from a suitable magnetized material such as polymeric ferrous oxide or the like of reverse polarity to the first sealing element  20 . In another exemplary practice, the second sealing element  22  may be a non-magnetized metal strip or other material having a magnetic attraction to the first sealing element  22 . The complementary sealing elements  20 ,  22  each may be secured in place to a surface of a deformable wall of the containment envelope  12  by any suitable technique including adhesives or the like as may be desired. Thus, the opposing deformable walls of the containment envelope may define support surfaces for the sealing elements  20 ,  22 . As will be appreciated, placement of the complimentary sealing elements  20 ,  22  at the exterior of the containment envelope  12  with the opposing deformable walls of the containment envelope forming a barrier between the wiper sheets  10  and the sealing elements ensures that the wiper sheets  10  are contacted only by the material forming the containment envelope. 
         [0019]    Regardless of the placement of the sealing elements  20 ,  22  they will be characterized by complimentary magnetic attraction such that pressing the first boundary edge  16  together with the second boundary edge  18  results in establishing an effective magnetic seal which holds the containment envelope  12  closed ( FIG. 2 ). In the sealed condition, evaporation of fluid saturating the wiper sheets may be substantially eliminated. In this regard, the combined effective thickness of the envelope material between the sealing elements  20 ,  22  is such that a magnetic sealing force may nonetheless be established and maintained when the opposing surfaces of envelope material are in contacting relation. Of course, this effective thickness may vary depending upon the strength of the magnetic force generated by the opposing sealing elements. In use, the sealing condition may be overcome by a user manually pulling the first boundary edge  16  and a second boundary edge  18  away from one another thereby applying a shear force to open the containment envelope  12  ( FIG. 1 ). When the sealing system of the present disclosure is used with the same film laminates used in prior known pliable containment envelopes, it has been found that evaporation is substantially eliminated in the sealed condition such that even with periodic opening and closing during use, evaporation losses are typically less than about 10% of the starting weight and will more preferably be less than about 5% and will most preferably be less than about 2%. 
         [0020]    In the illustrated exemplary construction, the body of the containment envelope  12  is preferably formed to include end gussets  30  (only one shown) on either end with a non-gusseted end seam  32  (only one shown) extending away from each gusset to the mouth opening  14 . Such a construction facilitates the packaging of a relatively large volume of wiper sheets  10  by expansion of the gussets  30  while avoiding excess material at the mouth opening. By way of example only, and not limitation, such a construction may be formed by folding a symmetrical panel  40  of foil laminate material as shown in  FIG. 3  along a bisecting fold line  42  and then heat sealing or otherwise connecting the overlying perimeter edges to form a three-dimensional structure. A gusseted envelope as shown in  FIGS. 1 and 2  is thereby provided. Of course, any number of other construction arrangements may be used as desired. 
         [0021]    The use of complimentary sealing elements to form a magnetic seal for the containment envelope  12  provides a number of performance benefits. By way of example only, since the seal is magnetic, there is no degradation in sealing strength following multiple uses. This may be contrasted with adhesive seals or physical seals which may degrade after multiple uses. Another benefit is that the seal may be easily activated by a user wearing gloves. Still another benefit is the reduced propensity for particle generation due to the absence of sliding contact between dissimilar surfaces. In this regard, the reduction in particle generation may be particularly great when the sealing elements  20 ,  22  are at the exterior of the containment envelope. Still another benefit is the ability to maintain chemical compatibility with the solvent or other saturating liquid. In this regard, the benefit of maintaining chemical compatibility may be particularly great with the sealing elements  20 ,  22  at the exterior of the containment envelope  12  since only the foil or other base material of the containment envelope  12  will contact the solvent or other saturating liquid. Moreover, in such an arrangement the seal is formed by the face to face contact of the foil or other base material forming the containment envelope  12 . Since such materials may be impermeable to the solvent, there is increased containment of any volatile emissions. 
         [0022]      FIGS. 4 and 5  illustrate another exemplary embodiment consistent with the present disclosure. In this exemplary embodiment, the wipe container  130  includes a tray body  132  of concave construction with an integral flange  134  disposed about the upper perimeter edge of the tray body  132 . A selectively displaceable lid  136  is provided to rest in covering relation to the tray body  132 . Both the tray body  132  and the lid  136  may be formed from materials such as PET, Mylar, high density polypropylene or the like which are substantially impermeable to any solvent saturating the wiper sheets (not shown) stored at the interior of the tray body  132 . If desired, the tray body  132  may be operatively connected to the lid  136  along a living hinge  140  or other hinging connection. However, the tray body  132  and the lid  136  also may be separate, independent structures. 
         [0023]    As shown, in the exemplary construction, a first arrangement of sealing elements  150  such as magnetic strips or the like as described previously is positioned along the perimeter of the lid  136  in a generally horseshoe shaped pattern following the free edges of the lid  136 . The first arrangement of sealing elements  150  may be formed from a suitable, magnetized material such as polymeric ferrous oxide or the like to define a magnet and may be secured in place to the surface of the lid  136  defining a support structure by any suitable technique including adhesives or the like as may be desired. 
         [0024]    As best seen in  FIG. 5 , the first arrangement of sealing elements  150  may be covered by an upper cap structure  152 . The upper cap structure  152  may be formed from the same material as the lid  136  and may be held in place by any suitable technique including adhesive bonding, melt bonding or the like. However, other materials of construction and attachment techniques also may be used. In the final construction, the upper cap structure  152  may substantially encapsulate the first arrangement of sealing elements  150 . Thus, the first arrangement of sealing elements  150  may be substantially isolated from other surfaces in the environment of use. This isolation may be beneficial in maintaining the integrity of the sealing elements as well as in avoiding any potential contamination from the material forming the first arrangement of sealing elements  150 . Of course, it is also contemplated that the upper cap structures may be eliminated if desired. 
         [0025]    As shown, the first arrangement of sealing elements  150  is positioned to be generally aligned with the surface of the flange  134  when the lid  136  is in a closed condition. A second arrangement of sealing elements  160  may be positioned at the underside of the flange  134 . In this regard, the second arrangement of sealing elements  160  may have a substantially mirror image pattern relative to the first arrangement of sealing elements  150 . Thus, in the illustrated exemplary construction, the second arrangement of sealing elements  160  has a generally horseshoe shaped pattern. However, other patterns also may be used. 
         [0026]    In one exemplary practice, the second arrangement of sealing elements  160  may be formed from a suitable magnetized material such as polymeric ferrous oxide or the like of reverse polarity to the first arrangement of sealing elements  150 . In another exemplary practice, the second arrangement of sealing elements  160  may be in the form of non-magnetized metal strips or other materials having a magnetic attraction to the first arrangement of sealing elements  150 . It is also contemplated that combinations of magnetized and non-magnetized materials may be used in the first arrangement of sealing elements  150  and/or in the second arrangement of sealing elements  160 . The second arrangement of sealing elements  160  may be secured in place to the underside of the flange  134  defining a support structure by any suitable technique including adhesives or the like as may be desired. 
         [0027]    As best seen in  FIG. 5 , the second arrangement of sealing elements  160  may be covered by a lower cap structure  162 . The lower cap structure  162  may be formed from the same material as the tray body  132  and may be held in place by any suitable technique including adhesive bonding, melt bonding or the like. However, other materials of construction and attachment techniques also may be used. In the final construction, the lower cap structure  162  may substantially encapsulate the second arrangement of sealing elements  160 . Thus, the second arrangement of sealing elements  160  may be substantially isolated from other surfaces in the environment of use. This isolation may be beneficial in maintaining the integrity of the sealing elements as well as in avoiding any potential contamination from the material forming the second arrangement of sealing elements  160 . Of course, it is also contemplated that the lower cap structure  162  may be eliminated if desired. 
         [0028]    The first arrangement of sealing elements  150  and the second arrangement of sealing elements  160  are characterized by magnetic attraction such that pressing the lid  136  against the flange  134  results in establishing a magnetic seal which holds the container  130  closed. In this regard, the combined effective thickness of the flange  134  and lid  136  between opposing magnetic strips  150 ,  160  is such that a magnetic sealing force may be established and maintained when the underside of the lid  136  contacts the upper surface of the flange  134 . Of course, this effective thickness may vary depending upon the strength of the magnetic force generated by the opposing sealing elements. During use, the sealing relation may be overcome to provide access to the interior by a user pulling the lid  136  away from the flange  134  thereby applying a shear force to open the container  130 . In this regard, the zones outboard from the sealing elements may define finger tabs to be grasped by a user during the opening procedure. 
         [0029]    As noted previously, in the illustrated exemplary arrangement, the complementary sealing elements  150 ,  160  are arranged in a generally horseshoe pattern extending along a forward edge and lateral sides of the container. In this arrangement, the lid  136  may remain attached along the living hinge  140 . Thus, the lid  136  may be lifted away from the tray body  132  to expose the access opening and then replaced with assured alignment of the opposing sealing elements. Of course, any number of other patterns for the magnetic strips may likewise be used if desired. 
         [0030]    The disclosure may be further understood through reference to the following non-limiting comparative examples. 
       COMPARATIVE EXAMPLES  
       [0031]    Three samples of the magnetic closure pouch packaging were prepared by placing a multitude of wipes in the pouch, saturated with a blend of 50% isopropanol and 50% acetone. For baseline control and comparison, a similar set of sample wipes was prepared, but placed in a pouch of the same material construction as the magnetic closure pouch, and thermally sealed closed. Once per day for thirty consecutive days, each magnetic closure pouch was opened briefly, then closed, to simulate removal of wipes, although no wipes were removed in order to maintain consistent weight and isolate the weight change due to solvent loss via evaporation. The control set of sealed-pouch wipes were not opened in order to establish the maximum solvent containment with the same materials of pouch construction. The weight of each pouch, from both sample sets, was then taken and recorded. Analysis consisted of averaging the weights of the three pouches in each sample set, and calculating the change in average pouch weight compared to the average weight at the start of the test (Day 0) for each day measurements were taken. The results are tabulated in Table 1 below. As can be seen, the magnetic seal pouches lost less than 1.5% of their total initial weight compared to completely sealed and undisturbed pouches of the same conditions. 
         [0000]    
       
         
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Day No.* 
                 Sample Weight, (Kg) 
                 Weight Loss, (%) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 0 
                 0.8420 
                 0.00% 
               
               
                 1 
                 0.8416 
                 −0.05% 
               
               
                 2 
                 0.8411 
                 −0.11% 
               
               
                 3 
                 0.8407 
                 −0.16% 
               
               
                 4 
                 0.8403 
                 −0.21% 
               
               
                 7 
                 0.8396 
                 −0.29% 
               
               
                 8 
                 0.8392 
                 −0.33% 
               
               
                 9 
                 0.8386 
                 −0.40% 
               
               
                 10 
                 0.8385 
                 −0.42% 
               
               
                 11 
                 0.8380 
                 −0.48% 
               
               
                 14 
                 0.8371 
                 −0.58% 
               
               
                 15 
                 0.8369 
                 −0.61% 
               
               
                 16 
                 0.8366 
                 −0.64% 
               
               
                 17 
                 0.8361 
                 −0.70% 
               
               
                 18 
                 0.8355 
                 −0.77% 
               
               
                 21 
                 0.8354 
                 −0.78% 
               
               
                 22 
                 0.8345 
                 −0.89% 
               
               
                 23 
                 0.8341 
                 −0.94% 
               
               
                 24 
                 0.8301 
                 −1.42% 
               
               
                 25 
                 0.8329 
                 −1.08% 
               
               
                 28 
                 0.8325 
                 −1.12% 
               
               
                 29 
                 0.8323 
                 −1.16% 
               
               
                 30 
                 0.8318 
                 −1.21% 
               
               
                 31 
                 0.8313 
                 −1.27% 
               
               
                   
               
               
                 *Break in number sequence due to weekends, when data was not collected. 
               
             
          
         
       
     
         [0032]    Of course, variations and modifications of the foregoing are within the scope of the present invention. Thus, it is to be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments and equivalents to the extent permitted by the prior art.