Patent Publication Number: US-2009226116-A1

Title: Dissolvable pouch

Description:
CROSS REFERENCE TO PRIOR APPLICATION 
     This application is based upon and claims the benefit of U.S. provisional application No. 61/068,201 filed Mar. 6, 2008. 
    
    
     BACKGROUND OF THE INVENTION 
     The present patent application is directed to a pouch manufactured utilizing water dissolvable or water dispersible paper and to a method for forming. It has long been known to package goods in water soluble pouches such as a film of polyvinyl alcohol (PVA). See for example U.S. Pat. No. 7,325,688. 
     SUMMARY OF THE INVENTION 
     Under the present invention, there is provided a pouch manufactured of water soluble or water dispersible paper and to a method for forming such pouch. A typical application for the pouch of the present invention includes packaging of dyes or chemicals which are utilized as additives to change ph or color in batch processing. The pouch of the present invention, including the heat seal adhesive utilized therein, totally dissolves or is dispersed upon being added to and mixed with a batch of water-based material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a sectional view of a laminate of water dissolvable paper and water dissolvable adhesive. 
         FIG. 2  is a plan view of the laminate of  FIG. 1 . 
         FIG. 3  is a view showing the laminate of  FIG. 2  folded about its center line and with the two edges on opposite sides the center line being heat sealed thereby providing a partially formed pouch. 
         FIG. 4  is a view similar to  FIG. 3  but showing a tube for dispensing a measured amount of contents into the partially formed pouch. 
         FIG. 5  is a view showing the filled and completely sealed pouch. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1 and 2 , there is shown a laminate  10  comprising a sheet of water soluble paper  12  and a coating of water soluble adhesive  14 . Shown in dashed lines in  FIG. 2  and identified by the numeral  16  is the center line of the laminate  10  about which the laminate is to be folded in forming the final pouch P as shown in  FIG. 5 . The laminate  10  has side edges  17  and  18 , an upper edge  20  and a lower edge  21  as viewed in  FIG. 2   
     Water dispersible paper  12  maybe obtained from Hollingsworth &amp; Vose Company, East Walpole, Mass. The water dissolvable adhesive  14  maybe obtained from Halltech, Inc., Toronto, Canada as its Item No. Thermseal 5A1-213M (V6). As a matter of efficiency, in applying the water dissolvable adhesive  14 , the entire surface of the water dissolvable paper  12  is covered with such adhesive  14 ; however, it is within the contemplation of the scope of the present invention that the pouch could be formed equally well if only the portions of the paper  12  adjacent the edges received such adhesive as it is only the portions adjacent such edges which become sealed as maybe seen in  FIG. 5 . The dissolvable adhesive  14  is a type which must be heat activated. 
     In order to form the pouch of the present invention, the sheet laminate  10  is initially folded about the center line  16  and the upper half of such laminate  10  is brought into contact with the lower half. Thus, the upper portion of edge  17  is brought into contact with the lower portion of edge  17  and the upper portion of edge  18  is brought into contact with the lower portion of edge  18 . Thus the paper  12  forms an exterior layer with the adhesive on the interior. 
     With the laminate  10  so folded, a heat seal device is heated to a temperature of 127° C. (plus or minus 10%) and is applied to the respective side edges  17  and  18  for approximately 1.2 seconds in order to seal the adjoined upper portion and lower portion of edge  17  and upper portion and lower portion of edge  18  to one another thereby forming a partially formed bag which is closed at the bottom center fold  16  and sealed at such edges  17  and  18 . Preferably the width of the seal extends inwardly from the respective edges  17  and  18  a distance of 1/16 inch to ⅜ inch. The top edge  20  is not sealed to its adjacent edge which, prior to folding, was the bottom edge  21 ; therefore, the partially formed bag is open at the top edge  20 . The exterior of the partially formed bag is water dispersible paper  12 . The water dissolvable layer of adhesive  14  is inwardly of the paper  12  covering at least the portions adjacent edges  17  and  18  and one or both of the top edge  20  and the bottom edge  21  but preferably covering the entire surface. 
     As shown in  FIG. 4 , a fill tube F may then be inserted into the open upper end  20  to dispense a measured quantity of product into the partially formed pouch. Thereafter, the upper edge  20  in contact with the previously disposed lower edge  21  may then be engaged by a heated sealing bar heated to a temperature of 142° C. (plus or minus 10%) for a period of 1.2 seconds to thereby form the filled and sealed pouch P as shown in  FIG. 5 . 
     The above detailed description of the present invention is given for explanatory purposes. It will be apparent to those skilled in the art that numerous changes and modifications can be made without departing from the scope of the invention.