Blister Strip for an Inhaler

Abstract

A blister strip ( 20 ) for use in a fluid or powder inhaler, and including a plurality of blisters, each formed by a reservoir ( 21 ) including an opening ( 25 ) that is sealed in leaktight manner by a tearable layer ( 7, 5 ), the blister strip ( 20 ) being characterized in that it comprises at least a base layer ( 6 ) that is provided with openings ( 25 ) forming the openings of the blisters, and a cavity layer ( 8 ) that is provided with cavities forming the blister walls ( 21 ), said tearable layer ( 7, 5 ) comprising a first tearable-layer portion ( 7 ) that is disposed between said base layer ( 6 ) and said cavity layer ( 8 ), and a second tearable-layer portion ( 5 ) that is disposed on the opposite side of said base layer ( 6 ), said first and second tearable-layer portions ( 7, 5 ) being connected together at each opening ( 25 ) of the base portion ( 6 ).

1 . A blister strip ( 20 ) for use in a fluid or powder inhaler, and including a plurality of blisters, each formed by a reservoir ( 21 ) including an opening ( 25 ) that is sealed in leaktight manner by a tearable layer ( 7 ,  5 ), the blister strip ( 20 ) being characterized in that it comprises at least a base layer ( 6 ) that is provided with openings ( 25 ) forming the openings of the blisters, and a cavity layer ( 8 ) that is provided with cavities forming the blister walls ( 21 ), said tearable layer ( 7 ,  5 ) comprising a first tearable-layer portion ( 7 ) that is disposed between said base layer ( 6 ) and said cavity layer ( 8 ), and a second tearable-layer portion ( 5 ) that is disposed on the opposite side of said base layer ( 6 ), said first and second tearable-layer portions ( 7 ,  5 ) being connected together at each opening ( 25 ) of the base portion ( 6 ). 
   
   
       2 . A blister strip according to  claim 1 , in which said first and second tearable-layer portions ( 7 ,  5 ) are made from the same material. 
   
   
       3 . A blister strip according to  claim 1 , in which said first and second tearable-layer portions ( 7 ,  5 ) are connected together as a single part in each opening ( 25 ) of the base layer ( 6 ). 
   
   
       4 . A blister strip according to  claim 3 , in which said single-part connection is made by fusing material. 
   
   
       5 . A blister strip according to  claim 1 , in which said tearable layer ( 7 ,  5 ) comprises polyethylene. 
   
   
       6 . A blister strip according to  claim 1 , in which each of said first and second tearable-layer portions ( 7 ,  5 ) are constituted by a continuous film of polyethylene. 
   
   
       7 . A blister strip according to  claim 1 , in which each of said first and second tearable-layer portions comprises a film having thickness that is less than 100 μm, advantageously lying in the range 10 μm to 40 μm, and preferably equal to 30 μm. 
   
   
       8 . A blister strip according to  claim 1 , in which said base layer ( 6 ) comprises polyester. 
   
   
       9 . A blister strip according to  claim 1 , in which said base layer ( 6 ) comprises a film having thickness that is less than 100 μm, advantageously lying in the range 40 μm to 60 μm, and preferably equal to 50 μm. 
   
   
       10 . A blister strip according to  claim 1 , in which said cavity layer ( 8 ) comprises polyethylene and/or polypropylene. 
   
   
       11 . A blister strip according to  claim 1 , in which said tearable layer ( 7 ,  5 ) further includes a first aluminum layer ( 2 ) that is fastened to said second tearable-layer portion ( 5 ). 
   
   
       12 . A blister strip according to  claim 11 , in which said first aluminum layer ( 2 ) has thickness that is less than 50 μm, advantageously lying in the range 10 μm to 30 μm, and preferably equal to 20 μm. 
   
   
       13 . A blister strip according to  claim 11 , in which a polyester layer ( 4 ) and an adhesive layer ( 3 ) are disposed between said second tearable-layer portion ( 5 ) and said first aluminum layer ( 2 ). 
   
   
       14 . A blister strip according to  claim 1 , in which said tearable layer ( 7 ,  5 ) includes a first outer layer ( 1 ), preferably formed by a printers' varnish. 
   
   
       15 . A blister strip according to  claim 1 , in which said cavity layer ( 8 ) further includes a second aluminum layer ( 11 ). 
   
   
       16 . A blister strip according to  claim 15 , in which a polyester layer ( 9 ) and an adhesive layer ( 10 ) are disposed between said cavity layer ( 8 ) and said second aluminum layer ( 11 ). 
   
   
       17 . A blister strip according to  claim 1 , in which said cavity layer ( 8 ) includes a second outer layer ( 13 ), preferably formed by a protective layer or by a layer of varnish, preferably interposed with an adhesive layer ( 12 ). 
   
   
       18 . A blister strip according to  claim 1 , in which the adherence of the tearable layer ( 7 ,  5 ) to the base layer ( 6 ) between the openings ( 25 ) is different from the adherence in the proximity of said openings ( 25 ). 
   
   
       19 . A blister strip according to  claim 1 , in which the blisters ( 21 ) contain a pharmaceutical powder. 
   
   
       20 . A dry-powder inhaler, characterized in that it includes a blister strip ( 20 ) according to  claim 1 .