Packaging laminate with gas and aroma barrier properties

Abstract

A packaging laminate ( 10 ) including a substrate film ( 15 ) coated with a carbon containing silicon oxide layer ( 16, 17 ) on both surfaces is disclosed herein. A method for producing the laminate ( 10 ), and blanks and packages fabricated from the laminate are also disclosed herein. The PECVD process of the present invention strains the substrate film ( 15 ) during deposition thereby creating a very thin oxide layer with superior durability, oxygen and aroma barrier properties. The carbon-containing silicon oxide coating ( 16, 17 ) has a stoichiometry of SiOxCy in which x is within the range of 1.5-2.2 and y is within the range of 0.15-0.80. The substrate film ( 15 ) may include a core layer ( 12 ) of a material selected from the group consisting of paper, paperboard, a foamed core, polyethylene terephtalate, polyamide, polyethylene and polypropylene.

1 . A method for manufacturing of a packaging laminate ( 10 ) having a thin silicone oxide coating ( 16  and  17 ) formed on each side of a substrate plastics film ( 15 ), 
 which comprises a step for obtaining said silicone oxide coatings by means of vapor-depositing a silicon oxide coating ( 16 ,  17 ) onto each side of the substrate film ( 15 ) by a plasma chemical vapour deposition (pecvd) method while straining the film, within a range between an upper limit of an initial plastic deformation of the substrate determined by the young modulus and a lower limit of any improvement of a cohesion force in the oxide coating and an adhesion force between the oxide coating and the substrate film:  
 
     
     
         2 . The method according to  claim 1 , wherein said silicon oxide coating comprises carbon-containing silicon oxide.  
     
     
         3 . The method according to  claim 1  or  2 , wherein said substrate film ( 15 ) comprises polyethylene terephthalate.  
     
     
         4 . The method according to  claim 2  or  3 , wherein said carbon-containing silicone oxide ( 16 ,  17 ) has the general composition formula; 
 SiOxCy, wherein x is within the range of 1.5-2.2 and y is within the range of 0.15-0.80.  
 
     
     
         5 . The method according to any of claims  2 - 4 , wherein said carbon-containing silicone oxide layer ( 16 ,  17 ) is formed from a mixture of vaporized organic silicon compound and oxygen in vacuum, the organic silicon compound being tetrahexamethyl disiloxane.  
     
     
         6 . The method according to any of claims  2 - 5 , wherein the cohesion strength in the carbon-containing silicone oxide layer ( 16 ,  17 ) is at least 5.7 GPa.  
     
     
         7 . The method according to any of claims  2 - 6 , wherein the carbon-containing silicone oxide layer ( 16 ,  17 ) has at least 170 MPa of interface shear strength with the substrate film ( 15 ).  
     
     
         8 . A packaging laminate including a substrate plastic film ( 15 ) having a thin silicone oxide layer ( 16 ,  17 ) formed on each side thereof, manufactured by the method according to any one of claims  1 - 7 .  
     
     
         9 . A packaging laminate having a thin silicone oxide coating ( 16 ,  17 ) formed on each side of a substrate plastic film ( 15 ), 
 the silicone oxide coating formed on each side of the substrate film being a carbon-containing silicone oxide coating obtained by vapor deposition with a plasma chemical vapour deposition (PECVD) method,    said carbon-containing silicone oxide having the general formula;    SiOxCy in which x is within the range of 1.5-2.2 and y is within the range of 0.15-0.80,    the carbon-containing silicone oxide layers ( 16 ,  17 ) having a cohesion strength of at least 5.7 GPa.    
     
     
         10 . The packaging laminate according to  claim 8  or  9 , wherein the carbon-containing silicone oxide layers ( 16 ,  17 ) have an interface shear strength with the substrate film of at least 170 MPa.  
     
     
         11 . The packaging laminate according to any of claims  8 - 10 , wherein the substrate film ( 15 ) comprises polyethylene terephtalate.  
     
     
         12 . The packaging laminate according to any of claims  8 - 11 , wherein the laminate includes a paper or paperboard layer ( 12 ).  
     
     
         13 . A packaging container comprising a flexible laminate ( 10 ) as defined in any of claims  8 - 12 .  
     
     
         14 . A packaging container comprising a flexible laminate ( 10 ) shaped to form the packaging container, 
 said laminate having a carbon-containing silicone oxide coating formed on each side of a substrate film,    said carbon-containing silicon oxide coatings ( 16 ,  17 ) being formed by vapor deposition on the substrate film by a plasma chemical vapour deposition (PECVD) method while straining the substrate film ( 15 ), within a range between an upper limit of an initial plastic deformation of the substrate film ( 15 ) determined by the Young modulus and a lower limit of any improvement of the cohesion force of the oxide coating ( 16 , 17 ) and the adhesion force between the oxide coating ( 16 ,  17 ) and the substrate film ( 15 ).    
     
     
         15 . The packaging container according to  claim 13  or  14 , wherein the substrate film ( 15 ) comprises polyethylene terephthalate.  
     
     
         16 . The packaging container according to any of claims  13 - 15 , wherein the carbon-containing silicone oxide has the general formula 
 SiOxCy in which x is within the range of 1.5-2.2 and y is within the range of 0.15-0.80.    
     
     
         17 . The packaging container according to any of claims  13 - 16 , wherein the carbon-containing silicone oxide layer ( 16 ,  17 ) is formed from a mixture of a vaporized organic silicon compound and oxygen in vacuum and the organic silicon compound is tetramethyl disiloxane.  
     
     
         18 . The packaging container according to any of claims  13 - 17 , wherein the cohesion strength in the carbon-containing silicone oxide layer ( 16 ,  17 ) is at least 5.7 GPa.  
     
     
         19 . The packaging container according to any of claims  13 - 18 , wherein the carbon-containing silicone oxide layers ( 16 ,  17 ) has an interface shear strength with the substrate film of at least 170 MPa.  
     
     
         20 . A package blank ( 2 ) having crease lines ( 3 ) and comprising a packaging laminate ( 10 ) having a thin silicone oxide coating ( 16 ,  17 ) formed on each side of a substrate plastic film ( 15 ), 
 the silicone oxide coatings ( 16 ,  17 ) formed on the substrate film ( 15 ) being carbon-containing silicone oxide coatings ( 16 ,  17 ) obtained by vapor deposition by the plasma chemical vapour deposition (PECVD) method,    the carbon-containing silicone oxide having the general formula;    SiOxCy in which x is within the range of 1.5-2.2 and y is within the range of 0.15-0.80,    and having at least 170 MPa of interface shear strength with the substrate film ( 15 ).    
     
     
         21 . The package blank ( 2 ) according to claim  20 , wherein the cohesion strength in the carbon-containing silicone oxide layer ( 16 ,  17 ) is at least 5.7 GPa.