Patent Publication Number: US-2017349348-A1

Title: Film for gas discharge and bag made from the same

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to bags and more particularly to a film for gas discharge and a bag made from the films for gas discharge. 
     2. Description of Related Art 
     Coffee beans are typically packaged in a bag such as plastic bag. Coffee beans may exhale to accumulate gas in the bag. Thus, the bag may expand and even explode due to gas expansion. Further, the inflated bag may hinder storage or delivery due to increased space. Thus, many inventors have thought how to solve the problem. 
     A conventional bag  90  is shown in  FIG. 7  and includes a check valve  91  for allowing gas in the bag  90  to pass through to expel. External air and pollutants are prevented from entering the bag  90  via the check valve  91 . 
     While the check valve  91  is good in its claimed function, its complicated components, time consuming assembly, and low production hinder its success in the market. 
     Thus, the need for improvement still exists. 
     SUMMARY OF THE INVENTION 
     It is therefore one object of the invention to provide a film for gas discharge comprising an inner film member; an outer film member; adhesive for securing the inner and outer film members together; an inlet disposed through the inner film member; an outlet disposed in the adhesive adjacent to ends of the inner and outer film members; a release member disposed between the inlet and the outlet; and a valve formed of non-adhesive plastic and disposed on the release member; wherein the valve is configured to close the release member to block a passage from the inlet to the outlet or open the release member to unblock the passage. 
     Preferably, the outlet is a hole. 
     Preferably, the inlet is a hole. 
     Preferably, the release member is formed of release agent and disposed between the outer film member and the adhesive. 
     Preferably, the release member is formed of release agent and disposed between the inner film member and the adhesive. 
     Preferably, the outer film member is formed of polyester, and the inner film member is a stack of aluminum (AL) layer, polyethylene (PE) layer, and hot adhesive layer made of linear low-density polyethylene (LLDPE) or polypropylene (PP). 
     Preferably, the outer film member is a stack of polyester layer, polyethylene (PE) layer, and aluminum (AL) layer, and the inner film member is a hot adhesive layer made of linear low-density polyethylene (LLDPE) or polypropylene (PP). 
     It is another object of the invention to provide a bag including two films secured together, at least one of the films being a film for gas discharge, the film for gas discharge comprising an inner film member; an outer film member; adhesive for securing the inner and outer film members together; an inlet disposed through the inner film member; an outlet disposed in the adhesive adjacent to ends of the inner and outer film members; a release member disposed between the inlet and the outlet; and a valve formed of non-adhesive plastic and disposed on the release member; wherein the valve is configured to close the release member to block a passage from the inlet to the outlet when an internal pressure of the bag is less than a predetermine pressure or open the release member to unblock the passage when the internal pressure of the bag is greater than the predetermine pressure. 
     Preferably, the outlet is a hole. 
     Preferably, the inlet is a hole. 
     Preferably, the release member is formed of release agent and disposed between the outer film member and the adhesive. 
     Preferably, the release member is formed of release agent and disposed between the inner film member and the adhesive. 
     Preferably, the outer film member is formed of polyester, and the inner film member is a stack of aluminum (AL) layer, polyethylene (PE) layer, and hot adhesive layer made of linear low-density polyethylene (LLDPE) or polypropylene (PP). 
     Preferably, the outer film member is a stack of polyester layer, polyethylene (PE) layer, and aluminum (AL) layer, and the inner film member is a hot adhesive layer made of linear low-density polyethylene (LLDPE) or polypropylene (PP). 
     Drawbacks of the conventional art including complicated components, time consuming assembly, and low production are eliminated by the invention. 
     The invention has the advantages of being mass produced, no additional assembly, and a bag or part thereof being made from the film for gas discharge. 
     The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is an exploded view of a film for gas discharge according to a first preferred embodiment of the invention; 
         FIG. 1B  is a plan view of the formed film for gas discharge; 
         FIG. 1C  is a sectional view taken along line  1 C- 1 C of  FIG. 1B  where the valve is closed; 
         FIG. 1D  is a view similar to  FIG. 1C  showing a channel formed by the open valve; 
         FIG. 1E  is a perspective view of the film for gas discharge wound into a roll; 
         FIG. 2  is a perspective view of a bag formed by the films for gas discharge; 
         FIG. 3  is an exploded view of a film for gas discharge according to a second preferred embodiment of the invention; 
         FIG. 4A  is an exploded view of a film for gas discharge according to a third preferred embodiment of the invention; 
         FIG. 4B  is a plan view of the formed film for gas discharge; 
         FIG. 4C  is a sectional view taken along line  4 C- 4 C of  FIG. 4B  where the valve is closed; 
         FIG. 4D  is a view similar to  FIG. 4C  showing a channel formed by the open valve; 
         FIG. 4E  is a perspective view of the film for gas discharge wound into a roll; 
         FIG. 5  is a perspective view of a bag formed by the films for gas discharge; 
         FIG. 6A  is an exploded view of a film for gas discharge according to a fourth preferred embodiment of the invention; 
         FIG. 6B  is a plan view of the formed film for gas discharge; 
         FIG. 6C  is a sectional view taken along line  6 C- 6 C of  FIG. 6B  where the valve is closed; 
         FIG. 6D  is a view similar to  FIG. 6C  showing a channel formed by the open valve; 
         FIG. 7  is a perspective view of a conventional bag. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1A to 1E , a film for gas discharge  100  in accordance with a first preferred embodiment of the invention comprises the following components as discussed in detail below. 
     An inner film member  11  and an outer film member  12  are secured together by adhesive  10 . The film for gas discharge  100  includes an inlet  111  shaped a circular hole (or a plurality holes in other embodiments), an outlet  121  at an end of the inner film member  11  (see  FIG. 1C ), a release member  13  disposed in the adhesive  10  and between the inlet  111  and the outlet  121 , and a valve  14  on the release member  13  adjacent to the inlet  111 . 
     In the first preferred embodiment, the release member  13  is made of release agent or any of similar materials. The release member  13  is disposed between the inner film member  11  and the adhesive  10 . 
     In the first preferred embodiment, the outer film member  12  is made of polyester such as polyethylene terephthalate (PET), the inner film member  11  is a stack of aluminum (AL) layer, polyethylene (PE) layer, and hot adhesive layer made of Linear low-density polyethylene (LLDPE) or polypropylene (PP). 
     In another first preferred embodiment, the outer film member  12  is a stack of polyester (e.g., PET) layer, PE layer, and AL layer, and the inner film member  11  is a hot adhesive layer made of LLDPE or PP. 
     In the first preferred embodiment, the film for gas discharge  100  is produced by a machine and wound into a roll (see  FIG. 1E ). The roll facilitates storage, delivery and mass production. 
     Referring to  FIG. 2 , a bag  200  produced either completely by a plurality of films for gas discharge  100  or by some films for gas discharge  100  and other components is shown. However, the manufacture of the bag  200  is not the subject of the invention and thus a detailed description thereof is omitted herein for the sake of brevity. Only the manufacture of the film for gas discharge  100  is discussed in detail below. 
     Referring to  FIGS. 1A-1E  and  FIG. 2  again, the inner film member  11  is an inner layer of the bag  200  and the outer film member  12  is an outer layer (i.e., outer surface) of the bag  200 . The film for gas discharge  100  is shaped as that shown in  FIG. 1C  when internal pressure of the bag  200  is less than a predetermine pressure. The valve  14  is closed to block (i.e., close) the release member  13 . Food (e.g., coffee beans) stored in the bag  200  may generate gas to expand the bag  200  by breathing. Internal pressure of the bag  200  thus increases. A channel  131  is formed and the valve  14  disengages from the release member  13  when the internal pressure of the bag  200  is greater than the predetermine pressure. Thus, gas in the bag  200  may enter the channel  131  via the inlet  11  and finally leave the bag  200  via the outlet  121  as indicated by arrows of  FIG. 1D . The bag  200  returns to the state of  FIG. 1C  when the internal pressure of the bag  200  is less than the predetermine pressure. In the closed state of the bag  200 , the release member  13  is blocked by the valve  14 , thereby preventing external gas and pollutants from entering the bag  200 . In the first preferred embodiment, the valve  14  is formed of rubber or acrylic. 
     Referring to  FIGS. 1A to 1E  again, the inlet  111  of the film for gas discharge  100  corresponds to the release member  13  (or a plurality of release members  13  in other embodiments). 
     Referring to  FIG. 3 , a film for gas discharge  300  in accordance with a second preferred embodiment of the invention is shown. The characteristics of the second preferred embodiment are substantially the same as that of the first preferred embodiment except the following: The inlet  111  of the film for gas discharge  300  corresponds to two release members  13  each having a valve  14  and an outlet  121 . The valve  14  is shaped as a ring around the inlet  111  and further disposed on the release members  13 . The valve  14  is an integral member. 
     The outlets  121  of the film for gas discharge  300  are at edges of the inner film member  11  and pressed by the outer film member  12 . Alternatively, the outlets  121  may be provided on the outer film member  12  in other embodiments. 
     Referring to  FIGS. 4A to 4E , a film for gas discharge  400  in accordance with a third preferred embodiment of the invention is shown. The characteristics of the third preferred embodiment are substantially the same as that of the first preferred embodiment such as the inner film member  11 , the outer film member  12 , the inlet  111 , the outlet  121 , the release member  13 , the valve  14 , and the adhesive  10  except the following: 
     The outlet  121  is provided through the adhesive  10  and the outer film member  12 . The outlet  121  is a through hole and adjacent to the release member  13 . 
     Referring to  FIG. 5 , a bag  700  produced either completely by a plurality of films for gas discharge  400  or by some films for gas discharge  400  and other components is shown. 
     Referring to  FIGS. 4A-4E  and  FIG. 5  again, the inner film member  11  is an inner layer of the bag  700  and the outer film member  12  is an outer layer (i.e., outer surface) of the bag  700 . In comparison with the outlet  121  at an edge of the inner film member  11  and pressed by the outer film member  12  of  FIG. 2 , the outlet  121  is provided through the adhesive  10  and the outer film member  12 . The film for gas discharge  400  is shaped as that shown in  FIG. 4C  when internal pressure of the bag  700  is less than a predetermine pressure. The valve  14  is closed to block (i.e., close) the release member  13 . Food (e.g., coffee beans) stored in the bag  700  may generate gas to expand the bag  700  by breathing. Internal pressure of the bag  700  thus increases. A channel  131  is formed and the valve  14  disengages from the release member  13  when the internal pressure of the bag  700  is greater than the predetermine pressure. Thus, gas in the bag  700  may enter the channel  131  via the inlet  11  and finally leave the bag  700  via the outlet  121  as indicated by arrows of  FIG. 4D . The bag  700  returns to the state of  FIG. 4C  when the internal pressure of the bag  700  is less than the predetermine pressure. In the closed state of the bag  700 , the release member  13  is blocked by the valve  14 , thereby preventing external gas and pollutants from entering the bag  700 . 
     Referring to  FIGS. 6A to 6D , a film for gas discharge  600  in accordance with a fourth preferred embodiment of the invention is shown. The characteristics of the fourth preferred embodiment are substantially the same as that of the first preferred embodiment except the following: 
     The release member  13  is sandwiched by the outer film member  12  and the adhesive  10  which is also partially sandwiched by the outer film member  12  and the inner film member  11 . The valve  14  is sandwiched by the release member  13  and the adhesive  10 . The inlet  111  is through the inner film member  11  and the adhesive  10  to terminate at the outer film member  12 . The outlet  121  is at an end of the release member  13 . The inlet  111  of the film for gas discharge  600  corresponds to the release member  13  (or a plurality of release members  13  in other embodiments). The release member  13  corresponds to a valve  14 . The valve  14  may be shaped as a ring around the inlet  111  in other embodiments. The outlet  121  is provided at end of the inner film member  11  or the outer film member  12 . Alternatively, the outlet  121  may be provided on the outer film member  12 . 
     While the invention has been described in terms of preferred embodiments, those skilled in the art will recognize that the invention can be practiced with modifications within the spirit and scope of the appended claims.