Abstract:
An improved water absorbing and retention bag has opposing bands about an outer bag. An inner bag has a supply of super absorbent polymer retained therein. The bands can provide loops from opposing ends of the bag while encircling the bag.

Description:
CLAIM OF PRIORITY 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Nos. 61/174,523 filed May 1, 2009 as well as 61/174,232 filed Apr. 30, 2009. Furthermore, this application is a continuation in part of U.S. patent application Ser. No. 11/549,333 filed Oct. 13, 2006. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to water absorbing and retention bags which can be utilized with, or in place of, sand bags for such uses as flood control, amongst others. 
       DESCRIPTION OF RELATED ART 
       [0003]    U.S. Pat. No. such as 6,715,960 and probably others in Class 405/114 describe super absorbent polymers (SAPs) utilized in a bag for flood control. However, the applicant has found that when testing products available on the market, the SAPs in the bags normally have a molecular weight less than one (i.e., they float), and they have a tendency to have extremely poor desorption characteristics. 
         [0004]    Floodbloc is a company selling a product with a bag available on the market which has an SAP with a molecular weight greater than one, and improved desorption characteristics over many other alternatives. However, the bag as being provided today is believed to have room for at least significant improvement. 
         [0005]    An improved water absorbing and retention bag is believed to be advantageous for many applications. 
       SUMMARY OF THE INVENTION 
       [0006]    It is an object of the present invention to provide improved bag constructions over prior art constructions. 
         [0007]    It is another object of the present invention to provide bag materials for at least some embodiments which at least assists in providing improved desorption characteristics. 
         [0008]    It is another object of at least some embodiments of the present invention to provide a bag which receives a pellitized SAP of known characteristics. 
         [0009]    It is another object of at least some embodiments of the present invention to provide a bag which has serged stitches which resist unraveling and/or separating. 
         [0010]    It is another object of at least some embodiments of the present invention to provide a bag having loops extending from sides of an exterior bag formed with bands stitched about the bag, possibly in the narrower dimension. 
         [0011]    It is yet another object of at least some embodiments of the present invention to provide a bag having a “firm pillow” inflation upon taking on water which facilitates stacking like sand bags preferably at about 40 pounds of weight while minimizing leakage around bags. See graph of  FIG. 5 . 
         [0012]    It is still another object of at least some embodiments of the present invention to invert at least the inner bag, if not both an inner and an outer bag after serging at least one of a side and an end to assist in potentially preserving the stitched portions. 
         [0013]    Accordingly, in a preferred embodiment of the present invention, a bag is preferably created with a first or inner bag configured to retain a preferred SAP therein. The SAP utilized preferably provides an absorption ratio of SAP to water of about 1/500. The SAP may be pelletized as one or more pellets and provided in a known amount to achieve a desired inflation of the inner bag with a desired weight. 31.5 grams of SAP as provided either as a single pellet or as a powder have been found to provide a “firm pillow” upon taking one water which sufficiently plugs leaks and provides stackability similar to sand bags. 
         [0014]    With a sheet of material such as 24×28 inches folded in half so that it is 24×14 inches. The side opposite the fold may be sewn (such as with serge stitching) as well as one of the two open ends. The SAP may then be inserted. An outer or second bag may then be constructed similarly, if not bought premade, but is preferably constructed out of different material. The outer bag may be 14×26 inches or other appropriate dimension when laid out flat. 
         [0015]    The inner bag may be a China twill such as 108×56 (weft and warf) with a 32 mesh weave and 100% cotton twill. The outer bag is 9 ounce woven jute material. Air permeability is preferably 28 or greater. The outer bag is preferably provided with an open end. Twill bands or tape encircles the front and back of the outer bag and is sewn to provide two loops (i.e., one on either side of the bag, one at the fold side, the other at the stitched side opposite the fold) near the sewn end of the outer bag. The inner bag with the SAP is inserted in the outer bag and the open end of the inner bag may be somewhat closely aligned with the open end of the outer bag and folded down over itself together with the open end of the outer bag. Another band of twill may be run over the fold and the folded end with tape is preferably surged to provide loop handles while sealing the inner bag inside of the outer bag with the palletized SAP contained and sealed within the inner bag. The loops may then be cut to provide strands for assisting in connecting bags or other structure to the bags. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which: 
           [0017]      FIG. 1A  is a top plan view of inner bag material prior to being made into the bag of  FIG. 1C  in accordance with a presently preferred embodiment of the present invention. 
           [0018]      FIG. 1B  is a top plan view of an outer bag of the presently preferred embodiment of the present invention. 
           [0019]      FIG. 1C  is a top perspective view of the inner bag constructed in accordance with a presently preferred embodiment of the present invention. 
           [0020]      FIG. 1D  is a top perspective view of the bag of  FIG. 1B  with twill tape loops installed in accordance with the presently preferred embodiment of the present invention. 
           [0021]      FIG. 2  shows a schematic representation of inserting the inner bag in the outer bag. 
           [0022]      FIG. 3  shows a top plan view illustrating the process of inserting the SAP into the inner bag; 
           [0023]      FIG. 4  is a top plan view of a bag constructed in accordance with the presently preferred embodiment; and 
           [0024]      FIG. 5  is a graph of carbohydrate (g/g) versus centrifugal force for a presently preferred ab initio process. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0025]    In accordance with a presently preferred embodiment of the present invention, an improved bag  10  can be provided as shown in  FIG. 4 . One way to construct the bag  10  of  FIG. 4  may be understood with reference to the remaining figures. 
         [0026]      Figure 1A  shows the start of the creation of inner bag  12  as shown in  FIG. 1C . Cotton twill material  14  having 108×56 (weft and warf), 32 mesh, and 100% cotton twill with dimensions of 28×24 is procured for use with a presently preferred embodiment. The material  14  may then be folded along its centerline  16  and the side  18  opposite folded side  20  can be stitched with stitching  22 , preferably serge stitches. A first end  24  may/is also preferably stitched, such as with serge stitches  26 . Chemical may then be inserted into inner bag  12  through open end  28  or otherwise at this time or later, as will be described below. 
         [0027]    Serge stitches  22 , 26  have been found to be particularly effective over other stitching methods for many embodiments. In some embodiments other stitches have had a tendency to spread apart, and then separate allowing expanding or expanded SAP to escape the inner bag  12 . Of course, either embodiments may use other stitching options. 
         [0028]    A premade outer bag  30  such as a 9 ounce woven jute material may be employed, or otherwise fabricated as shown in  FIG. 1B . The applicant has used one having dimensions of 14×26 with an open end  32 . Side  34  and end  36  can be sewn, such as by serging or otherwise secured together. Side  38  may be sewn or folded. 
         [0029]    Loops  40 , 42  are formed with tape or band, such as twill band  44  which may be sewn to the outer bag  30  toward closed end  36 . The band  44  preferably encircles the front and back of the outer bag  30  and may be top stitched to the outer bag  30 . Loops  40 , 42  may have a length of six inches or other dimension and may be cut into straps after forming the loops to facilitate tying the outer bag  30  to other bags  30  or structures. Twill tape  44  may have a length of about 53 inches prior to encircling the outer bag  30  as shown, and then being sewn as shown. It is preferable not to entrap the inner bag  12  to the outer bag  30  when stitching the twill tape  44  to the outer bag  30  at the closed end  36  but could be done in some embodiments. 
         [0030]      FIG. 2  shows the process of inserting the inner bag  12  into outer bag  30 . With the inner bag  12  in the outer bag, if the SAP has not already been inserted into the inner bag  12 , it may be inserted whether in particulate form  46  or as one or more pellets  48 . Next the open ends of bags namely  28 , 32  may be folded back to provide flaps  50  over a portion of front side of outer bag  30 . Twill tape  52  may then be utilized towards folded end  54  over at least a portion of flaps  50  to assist in containing the inner bag  12  in the outer bag  30  as well as the SAP in the inner bag  12 . 
         [0031]    Twill tape  52  may be sewn to the outer bag  30  such as with topstitch as shown. Loop handles  54  may preferably be formed in somewhat of a similar manner as loops  40 , 42  were formed at the other end with tape  44 . 
         [0032]    The material selection for the inner bag  12  and outer bag  30  has been performed with trial and error based on desorption characteristics of the SAP employed. Specifically with the SAP utilized, a 10-14 day desorption rate is achieved as long as the humidity remains at or under 60%. At least some other materials tested maintained the SAP moist longer thereby creating desorption issues. The SAP utilized has a molecular weight greater than one, such as 1.6. 
         [0033]    31.5 grams of SAP water as particulate  46  or pellet(s)  48  with an absorption ratio of 1/500 has been found to satisfactorily fill up the volume of bag  10  to provide a “firm pillow” feel which also has a weight of about 40 pounds (that normally specified for sand bags). The firm pillow feel allows the bag  10  to fill and plug leaks in a preferable manner. Too inflated causes leakage issues against adjacent bags. A lack of inflation can also cause the bags to leak at adjacency areas. 
         [0034]    Another advantageous embodiment provides for the inversion of at least one of the inner or outer bags  12 , 30  after stitching the side and end  18 , 24  and/or  34 , 36 . By turning at least one of the bags  12 , 30  inside out, there is less of a chance of stitching coming unraveled or disengaged from the appropriate bag  12 , 30 . Furthermore, serging the stitches has been found to assist in many embodiments. 
         [0035]    After using the bags  10 , the bags  10  can be desorbed and stored for future use. The cycle life of bags  10  is not normally intended to be indefinite, but may more likely be 2-5 cycles in some embodiments. The SAP may also be rendered inert with the application of a high pH bath which can break down bonds prior to disposal in a landfill. 
         [0036]    Bags  10  can be utilized for many applications. If pre-wetted bags  10  may not absorb much, if any, contaminants in the environment. Furthermore, rinsing off the bags  10  after use, may prevent any contaminants from entering the SAP. 
         [0037]    Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to the preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. 
         [0038]    Having thus set forth the nature of the invention, what is claimed herein is: