Patent Publication Number: US-2007095880-A1

Title: Packaging material

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a packaging material comprising a packaging sheet opening mechanism.  
      2. Description of the Conventional Art  
      Many kinds of the packaging material have been conventionally used for packaging each piece of food such as a sushi, confectionery or other items.  
      For example, a packaging material illustrated in  FIG. 10  is for the sushi, and is used by forming a packaging sheet  100  made from a rectangular transparent plastic film, putting the packaging sheet  100  on a sushi  101  from an upper side so as to adhere closely thereto, folding and attaching an end edge of the packaging sheet  100  to the lower face of the sushi  101 , and sealing an folded portion  102  by heating to prevent unnecessary opening (referring to Japanese Patent Application Laid Open No. 3(1991)-53858).  
     SUMMARY OF THE INVENTION  
      However, as shown in  FIG. 11 , when eating the sushi  101  packaged with the packaging sheet  100 , it is necessary for opening the sheet  100  to carry out reversing works of turning the lower face of the sushi  101 , that is, the folded portion  102  of the packaging sheet  100  upwardly, detaching the heat seal, taking out the sushi  101  from the packaging sheet  100 , and turning the taken out sushi  101  again to return to the first state. Thus, there are problems that troublesome time and effort are required before eating it.  
      Further, since considerable force is necessary in order to detach the heat seal portion, there is a problem that the sushi  101  in the packaging sheet  100  is squeezed, or accidentally dropped from a hand.  
      Then, the present invention solves the above-described problems of the conventional techniques, and an primary objective of the present invention is to provide a packaging material having a opening mechanism capable of easily opening a package by only an one-touch operation of pulling an upper face of a packaging sheet packaging a food or other items in counter directions.  
      For achieving the above-described objective, the present invention has the following characteristics. In a first aspect thereof, the packaging material is provided with a packaging sheet opening mechanism comprising a perforated line formed at a packaging sheet, and a belt-shaped cover sheet provided at the inside of the perforated line of the packing sheet so as to position the perforated line approximately at a center in the longitudinal direction, one side end edge in the longitudinal direction of the belt-shaped over sheet being adhered so as not to contact with the perforated line.  
      In a second aspect, a transparent, translucent or opaque plastic film is used as the packing sheet and the belt-shaped cover sheet mentioned above.  
      In a third aspect, the belt-shaped cover sheet is adhered to the packing sheet with heat sealing, in the packing sheet opening mechanism mentioned above.  
      In a fourth aspect, the belt-shaped cover sheet is adhered to the packing sheet with an adhesive, in the packing sheet opening mechanism mentioned above.  
      As described above, in the present invention, the packaging material has the packaging sheet opening mechanism comprising the perforated line formed at a packaging sheet and the belt-shaped cover sheet provided at the inside of the perforated line of the packing sheet so as to position the perforated line approximately at the center in the longitudinal direction, the one side end edge in the longitudinal direction of the belt-like cover sheet being adhered so as not to contact with the perforated line. Thus, the present invention has the following effects.  
      1. Since the lower side of the perforated line formed at the packaging sheet is covered with the belt-shaped cover sheet, it can be prevented that dust, various germs or the like invade from the outside.  
      2. It can be prevented that the food dries or discolors by introduction of air, and thus the taste and freshness can be kept for a long time.  
      3. Since the one side end edge of the belt-shaped cover sheet, which covers the lower side of the perforated line of the packaging sheet, is adhered and fixed so as not to contact with the perforated line, the belt-shaped cover sheet does not become an obstacle when pulling the packaging sheet in the counter directions to cut the perforated line, and thus the sheet opening work can be carried out smoothly and speedy with a one-touch operation 
    
    
     BRIEF EXPLANATION OF DRAWINGS  
       FIG. 1  is a front view illustrating a packaging material according to the present invention.  
       FIG. 2  is a rear view of  FIG. 1 .  
       FIG. 3  is a cross-sectional view taken along a line A-A of  FIG. 1 .  
       FIGS. 4A and 4B  are enlarged cross-sectional views of a main part, in which  FIG. 4A  illustrates before separation, and  FIG. 4B  illustrates after separation.  
       FIG. 5  is a plan view illustrating a using state.  
       FIG. 6  is a plan view of another side of FIG.  5  also illustrating the using state.  
       FIG. 7  is a cross-sectional view along arrows B-B of  FIG. 5 .  
       FIG. 8  is a cross-sectional view same as  FIG. 7  when opening a film.  
       FIG. 9  is a perspective view illustrating a state in which a packaging sheet is formed to be a roll.  
       FIG. 10  is a perspective view illustrating a state in which a sushi is packaged with a conventional packaging sheet.  
       FIG. 11  is a perspective view illustrating a state when opening the sushi in  FIG. 10 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENT  
      Hereinafter, one preferred embodiment for carrying out the present invention is described with drawings. In the drawings,  1  is a rectangular packaging sheet and has a packaging sheet opening mechanism  2  approximately at a center thereof in the longitudinal direction.  
      As the packaging sheet  1 , the transparent, translucent or opaque plastic film is suitable. For example, a plastic film comprising polypropylene, polyethylene, polyethylene terephthalate or the like, or a paper coated with these plastics is suitable.  
      Further, as for the constitution of the packaging sheet opening mechanism  2  provided approximately at the center of the packaging sheet  1 , a perforated line  3  is formed in overall length approximately at the center in the longitudinal direction of the rectangular packaging sheet  1 . Further, a belt-shaped cover sheet  4  is provided at the inside of the perforated line  3  of the packaging sheet  1  so as to position the perforated line  3  approximately center in the longitudinal direction. Further, one side end edge in the longitudinal direction of the belt-shaped cover sheet  4  is adhered to the packaging sheet  1  so as not to contact it with the perforated line  3 .  
      The belt-shaped cover sheet  4  may be adhered to the packaging sheet  1  with any one of heat sealing and an adhesive.  5  in the drawings is the adhering portion.  
      In addition, the rectangular packaging sheet  1  having the packaging sheet opening mechanism  2  illustrated in  FIG. 1  or  3  can be made by forming a roll  11  having a continuous packaging sheet opening mechanism  2  and cutting the roll  11  to have the predetermined length, as illustrated in  FIG. 9 .  
      Then, the packaging sheet  1  comprising the above constitution packages a packaged item  6  so as to provide the packaging sheet opening mechanism  2  approximately at the center of the upper face of the packaged item  6 , as illustrated in  FIG. 5  or  8 .  
      That is, in  FIGS. 5 and 7 , a round confectionery  6   a  is packaged with the packaging sheet  1 , and the packaging sheet opening mechanism  2  is provided approximately at the center of the upper face of the round confectionery  6   a . On the other hand, in  FIG. 6 , a sushi  6   b  is packaged with the packaging sheet  1 , and the packaging sheet opening mechanism  2  is provided in a diagonal direction on the upper face of the sushi  6   b.    
      Then, for opening the packaging sheet opening mechanism  2  on the upper face of the packaging sheet  1  packaging the packaged item  6 , both sides of the perforated line  3  in the upper face of the packaging sheet  1  are pulled in counter directions while pressing the both sides by two fingertips respectively, to thereby tear the perforated line  3  to the right and left. Thus, since the upper face of the packaging sheet  1  is opened widely, the packaged item  6  inside the packaging sheet  1  can be easily taken out.  
      At this time, since the belt-shaped cover sheet  4  covers the perforated line  3  of the packaging sheet  1  from the inside in a fitting state, it can be prevented that various germs, dust or the like that from the outside. Further, since the adhering portion  5  of the belt-shaped cover sheet  4  with the packaging sheet  1  is not contacted with the perforated line  3 , there is no obstacle in the cutting work.