Patent Publication Number: US-2007095830-A9

Title: Self-closing packaging for moisture-sensitive material

Description:
The invention is directed to a packaging for moisture-sensitive material, in particular detergent material.  
      Commonly, moisture-sensitive material, such as detergent material, e.g. detergent powder, granules, tablets or detergents contained in water-soluble sachets, are packaged in containers made of cardboard material with a lining of water-impermeable sheet material to protect the contents from absorption of water from the atmosphere. However, the user has to make sure that the packaging is closed again after usage. If not, the moisture-sensitive material can chemically degrade potentially affecting the activity of ingredients or suffer a negative impact on its physical properties (i.e. resistance, solubility, . . . ). Additionally, there may be a substantial loss of volatile material such as perfume from the material, when the container is not tightly closed.  
      Although this negative impact on moisture is undesirable in general, it is particularly problematic in the case of tablets not individually wrapped in a moisture isolating film or even worse in the case of detergents packaged in water-soluble monodose sachets, for instance in PVOH sachets. Such sachets are getting sticky when absorbing water from the atmosphere, resulting in adhering to each other. When trying to separate such adhered sachets, destroying of the water-soluble film material is highly likely. Moreover, undesirable loss of water from the contents of such sachets is another problem if they are not contained in a tight packaging.  
      The object of the invention therefore is to provide for a tight packaging ensuring reliable protection of the contents thereof from moisture in the atmosphere and/or avoiding escape of volatile material from the packaging. This object is solved by a packaging comprising an outer container comprising a container body and a lid cover hingedly fixed to the container body, and an inner bag made of water-impermeable flexible sheet material for receiving the moisture-sensitive material, the mouth of the inner bag being fixed both at the lid cover and at the sidewalls of the container body in such a way that, when the lid cover is lifted, the lower part of the inner bag is significantly lifted from the bottom of the container body.  
      In a preferred embodiment of the invention, the mouth of the inner bag is fixed at the edge portion of the lid cover being opposite to the hinged portion thereof and at least at the edge portion of the container body being adjacent to the said edge portion of the lid cover in the closed state of the outer container.  
      In the most preferred embodiment, the inner bag is fixed at no other portion of the outer container.  
      The invention is also directed to the use of a packaging according to the invention for packaging material containing volatile ingredients or water-soluble sachets containing detergent material.  
      The packaging of the present invention provides for a system ensuring automatic self-closing of the packaging after having been opened by the user to take out a portion of the powder or granules or one or more tablets or sachets in order to protect the moisture-sensitive contents thereof. The invention is based on providing an inner bag which is relatively loose within the outer container, i.e. basically only the mouth of the inner bag being fixed thereto.  
      However, the inventive packaging does not only provide for a reliable protection of the contents thereof from moisture in the atmosphere, but is also a tight packaging in another sense, namely by avoiding escape of volatile matter from the packaging. Such volatile material may, for example, be perfume commonly used in detergent material. In case of the preferred use of the inventive packaging, namely for water-soluble sachets containing detergent material, the tight packaging of the present invention also avoids “drying out” of the sachets, i.e. loss of water or other liquids from the material contained therein by migration across the film material of the sachets.  
      It is essential to at least fix one portion of the mouth of the inner bag to the lid cover and another portion to a sidewall of the container to allow opening of the inner bag by lifting the lid cover. For stability of the package, the inner bag filled with the moisture-sensitive material will preferably be close to or even at least partly supported on the bottom of the container in its closed state. It is, however, essential for the invention that the lower part of the inner bag will be substantially lifted from the bottom when lifting the lid cover for opening the package. Only then, it can be guaranteed that the weight of the contents of the inner bag, by gravitational effect, will draw back the lid cover to its closed state when released by the user. There are no specific restrictions for the materials used for the outer container and the inner bag of the package of the present invention with the exception that the inner bag should be made of water-impermeable flexible sheet material to allow protection of the contents and, by the form of a loose bag, to function according to the invention. Such water-impermeable sheet material may be polyethylene or any other polymeric sheet material with comparable characteristics. The outer container may be made out of cardboard material although not restricted thereto.  
      In an alternative embodiment to the present invention there is provided packaging for moisture sensitive material comprising an outer container including a container body and a lid movable between an open and a closed position relative to the container body, and an inner container made of water-impermeable material for receiving the moisture sensitive material, the inner container being fixed to both the container body and the lid of the outer container such that when the lid is moved from the closed position to the open position, a lower part of the inner container is lifted relative to its position when the lid is in the closed position such that in use, the lid is biased to the closed position.  
      The lid may be pivotable between the open and the closed position, or it may be slidable between the two positions.  
      The inner container may be comprised of foldable sheet water-impermeable material or from flexible water impermeable material. 
    
    
      The invention is explained in more detail by the following examples represented by the drawings wherein  
       FIG. 1  shows a cross-sectional view of a packaging according to a first embodiment of the present invention in its closed state; and  
       FIG. 2  shows a cross-sectional view of the same packaging in its opened state.  
       FIG. 3  shows a perspective view of the same packaging in its opened state.  
       FIG. 4  shows a cross-sectional view of a packaging according to a second embodiment of the present invention in its opened state. 
    
    
      The packaging of the present invention comprises an outer container  10  comprising a container body consisting of upright sidewalls  11  and a bottom  12 . At position  15  at the upper end of one of the sidewalls  11  a lid cover  13  is hingedly fixed thereto. The portion of the lid cover  13  being opposite to the hinged portion  15  is designated in the drawings by reference numeral  14  and the edge portions of the sidewalls  11  of the container body being adjacent to the edge portion  14  of the lid cover when the packaging is in its closed state, are designated by reference numeral  16 .  
      The contents  30  of the packaging (in the example detergent tablets or water-soluble sachets filled with detergent material) are contained in an inner bag  20  made of flexible sheet material. The mouth of the inner bag  20  is fixed at the edge portion  14  of the lid cover  13  as well as at the edge portions  16  of the sidewalls  11  of the container body. In the closed state of the container, as represented in  FIG. 1 , the lowest part of the inner bag  20  is close to or even supported on the bottom  12  of the container body.  
      It is an essential feature of the packaging of the present invention that the mouth of the inner bag  20  is opened when lifting the lid cover  13  as represented by the double arrow of  FIG. 2 . At the same time, it is essential that the lower part of the inner bag is significantly lifted from the bottom  12  of the outer container  10  in order to ensure that, by gravitational force, the weight of the contents of the inner bag will draw back the lid cover  13  to its closed state after release as indicated by the large downward arrow in  FIG. 2 .  
      The features disclosed in the foregoing description, claims and/or drawings may, both separately and in any combination thereof, be material realising the invention in the deiverse forms thereof.