Multi-chamber container

Abstract

There is disclosed a multi-chamber container comprising a resin film or sheet formed into a bag shape by heat-sealing and having a partition portion formed therein which includes a heat-sealed portion comprising a specific propylene-based resin composition obtained by multi-stage polymerization. The multi-chamber container has a large difference in heat-seal strength between the partition portion and peripheral portions of the container as compared to conventional containers, and facilitates control of the temperature of a heat-sealing mold upon formation of the partition portion. Further, the multi-chamber container is excellent in safety, flexibility, transparency and heat resistance and, therefore, can be used in medical applications.

What is claimed is:  
     
         1 . A multi-chamber container comprising a resin film or sheet formed into a bag shape by heat-sealing and having a partition portion formed therein, said multi-chamber container including a heat-sealed portion comprising a propylene-based resin composition containing the following component (A) obtained by a first-stage polymerization and the following component (B) obtained by a second-stage polymerization such that the components (A) is contained in an amount of 10 to 60% by weight and the components (B) is contained in an amount of 40 to 90% by weight, based on a total weight of the components (A) and (B): 
 Component (A): a polymer component containing propylene having an isotactic index of not less than 90% as a main component; and    Component (B): a copolymer component comprising a copolymer produced from propylene and an α-olefin other than propylene having not more than 8 carbon atoms with the proviso that propylene and ethylene are contained therein as essential components, and containing a room-temperature xylene-insoluble component in an amount of from more than 20% by weight to 70% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), and a room-temperature xylene-soluble component in an amount of from 10 to 60% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), said room-temperature xylene-soluble component having a content of the α-olefin other than propylene of less than 20% by weight.    
     
     
         2 . A multi-chamber container according to  claim 1 , wherein the resin films or sheets constituting the partition portion are peelable off from each other.  
     
     
         3 . A multi-chamber container according to  claim 1 , wherein the propylene-based resin composition satisfies the following requirements (i) to (iv): 
 (i) a propylene content in whole polymers as a sum of the components (A) and (B) is within the range of 85 to 95% by weight;    (ii) a content of the α-olefin other than propylene (hereinafter referred to merely as “αt”; unit: % by weight) and a content of a room-temperature xylene-soluble component (hereinafter referred to merely as “CXS”) in the whole polymers as a sum of the components (A) and (B) satisfies the following formula:      CXS >5α t −25    wherein αt is 5 to 15% by weight;    (iii) a melting point peak temperature thereof is not less than 160° C.; and    (iv) a tensile stress at a yielding point thereof is not more than 15 MPa.    
     
     
         4 . A multi-chamber container according to  claim 1 , wherein the resin film or sheet includes three or more layers comprising an innermost layer comprising a propylene-based resin composition, an intermediate layer comprising a resin composition containing a propylene-based resin composition and a styrene-based elastomer, and an outermost layer comprising a propylene random copolymer resin or a resin composition containing a propylene-based resin composition and a propylene random copolymer resin.  
     
     
         5 . A multi-chamber container comprising a resin film or sheet formed into a bag shape by heat-sealing and including a partition portion formed therewithin, said multi-chamber container having a heat-sealed portion comprising a propylene-based resin composition satisfying the following requirements (i) to (iv): 
 (i) a propylene content thereof is within the range of 85 to 95% by weight;    (ii) a content of an α-olefin other than propylene (hereinafter referred to merely as “αt”; unit: % by weight) and a content of a room-temperature xylene-soluble component (hereinafter referred to merely as “CXS”) in the whole polymers as a sum of the components (A) and (B), satisfy the following formula:      CXS >5α t −25    wherein at is 5 to 15% by weight;    (iii) a melting point peak temperature thereof is not less than 160° C.; and    (iv) a tensile stress at a yielding point thereof is not more than 15 MPa.    
     
     
         6 . A multi-chamber container according to  claim 5 , wherein the propylene-based resin composition comprises the following component (A) obtained by a first-stage polymerization and the following component (B) obtained by a second-stage polymerization such that the components (A) is contained in an amount of 10 to 60% by weight and the components (B) is contained in an amount of 40 to 90% by weight, based on a total weight of the components (A) and (B): 
 Component (A): a polymer component containing propylene having an isotactic index of not less than 90% as a main component; and    Component (B): a copolymer component comprising a copolymer produced from propylene and an α-olefin other than propylene having not more than 8 carbon atoms with the proviso that propylene and ethylene are contained therein as essential components, and containing a room-temperature xylene-insoluble component in an amount of from more than 20% by weight to 70% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), and a room-temperature xylene-soluble component in an amount of from 10% by weight to 60% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), said room-temperature xylene-soluble component having a content of the α-olefin other than propylene of less than 20% by weight.    
     
     
         7 . A multi-chamber container according to  claim 5 , wherein the resin films or sheets constituting the partition portion are peelable off from each other.  
     
     
         8 . A multi-chamber container according to  claim 5 , wherein the resin film or sheet includes three or more layers comprising an innermost layer comprising the propylene-based resin composition, an intermediate layer comprising a resin composition containing the propylene-based resin composition and a styrene-based elastomer, and an outermost layer comprising a propylene random copolymer resin or a resin composition containing the propylene-based resin composition and the propylene random copolymer resin.  
     
     
         9 . A multi-chamber container comprising a resin film or sheet formed into a bag shape by heat-sealing and having a partition portion formed therein, said multi-chamber container having a heat-sealed portion comprising a propylene-based resin composition satisfying such a requirement that a difference between a heat-sealing temperature (T 1 ) (° C.) providing a heat-seal strength of 0.2 kgf/15 mm and a heat-sealing temperature (T 2 ) (° C.) providing a heat-seal strength of 2.0 kgf/15 mm (T 2 −T 1 ) is not less than 20° C., and exhibiting a heat-seal strength of not less than 3 kgf/15 mm.  
     
     
         10 . A multi-chamber container according to  claim 9 , wherein the propylene-based resin composition comprises the following component (A) obtained by a first-stage polymerization and the following component (B) obtained by a second-stage polymerization such that the components (A) is contained in an amount of 10 to 60% by weight and the components (B) is contained in an amount of 40 to 90% by weight, based on a total weight of the components (A) and (B): 
 Component (A): a polymer component containing propylene having an isotactic index of not less than 90% as a main component; and    Component (B): a copolymer component comprising a copolymer produced from propylene and an α-olefin other than propylene having not more than 8 carbon atoms with the proviso that propylene and ethylene are contained therein as essential components, and containing a room-temperature xylene-insoluble component in an amount of from more than 20% by weight to 70% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), and a room-temperature xylene-soluble component in an amount of from 10% by weight to 60% by weight based on a total weight of whole polymers as a sum of the components (A) and (B), said room-temperature xylene-soluble component having a content of the α-olefin other than propylene of less than 20% by weight.    
     
     
         11 . A multi-chamber container according to  claim 9 , wherein the propylene-based resin composition satisfies the following requirements (i) to (iv): 
 (i) a propylene content thereof is 85 to 95% by weight;    (ii) a content of an α-olefin other than propylene (hereinafter referred to merely as “αt”; unit: % by weight) and a content of a room-temperature xylene-soluble component (hereinafter referred to merely as “CXS”) in the whole polymers as a sum of the components (A) and (B), satisfy the following formula:      CXS> 5α t −25    wherein at is 5 to 15% by weight;    (iii) a melting point peak temperature thereof is not less than 160° C.; and    (iv) a tensile stress at a yielding point thereof is not more than 15 MPa.    
     
     
         12 . A multi-chamber container according to  claim 9 , wherein the resin films or sheets constituting the partition portion are peelable off from each other.  
     
     
         13 . A multi-chamber container according to  claim 9 , wherein the resin film or sheet includes three or more layers comprising an innermost layer comprising the propylene-based resin composition, an intermediate layer comprising a resin composition containing the propylene-based resin composition and a styrene-based elastomer, and an outermost layer comprising a propylene random copolymer resin or a resin composition containing the propylene-based resin composition and the propylene random copolymer resin.