Patent ID: 8163361

Claim:
A multichamber infusion solution bag, comprising: a bag mainbody having a rectangular bag shape formed from a pliable plastic film comprising a heat sealable sealing layer, the bag mainbody being formed by heat sealing peripheral portions of a pair of pliable plastic films being laid one upon another so that the sealing layers thereof face with each other, wherein the sealing layers are inside layers of the bag; a sealed portion for enclosing a chamber for filling with an infusion solution formed by heat sealing the peripheral portions of the pair of pliable plastic films; and an easily releasable sealed portion for dividing an upper chamber and a lower chamber of said chamber, the easily releasable sealed portion being formed by heat sealing an intermediate portion of the chamber, wherein one end and an other end of the easily releasable sealed portion are connected with the peripheral sealed portions respectively, the sealing layer being made of a mixture of a polypropylene-α-olefin random copolymer having a crystalline melting point Tm of 138° C. and a polypropylene homopolymer having a crystalline melting point Tm of 163° C.; an allowable sealing temperature range of the easily releasable sealed portion being at least a two degrees range and a peel strength of said easily releasable sealed portion being set within a range from 3.92 to 5.88 N/15 mm after a sterilization treatment, which is measured in accordance with the method described in JIS Z 0237 as 180° peel method, the peel strength of said easily releasable sealed portion being weaker than a peel strength of said peripheral sealed portions.