Method and apparatus for producing a sterilizable package of a product, and the packaged product

Claim 3

A method as claimed in claim 1, wherein an internal corner is formed at the seal and the deformation of the closure forces product to completely fill the internal corner.

Claim 4

A method as claimed in claim 1, wherein, around the periphery of the charging opening, the material of the closure curves smoothly from the periphery of the charging opening into the charging opening.

Claim 5

A method as claimed in claim 1, wherein the container is of thermoplastics material.

Claim 6

A method as claimed in claim 1, wherein the closure is deformed by the application of super-atmospheric fluid pressure to its outer surface.

Claim 7

A method as claimed in claim 1, wherein deformation of the closure is at least assisted by the application of mechanical force to its outer surface.

Claim 8

A method as claimed in claim 1, wherein the deformation of the closure is effected after the opening has been sealed by the closure, the sealing of the opening being itself effected at a time when the headspace associated with the opening is subject to a largely reduced gas pressure.

Claim 9

A method as claimed in claim 1, wherein the deformation of the closure is effected before the closure is heat-sealed around the opening.

Claim 10

A method as claimed in claim 8, wherein the deformation of the closure is effected at a time when the container is located within a largely reduced gas pressure environment.

Claim 11

A method as claimed in claim 1, wherein the closure is heat-sealed to the container at a heat seal region of the closure.

Claim 12

A method as claimed in claim 10, wherein the closure is a diaphragm of stretchable and relatively flexible sheet material.

Claim 13

A method as claimed in claim 11, wherein the diaphragm is formed from within a sheet of the said stretchable and relatively flexible sheet material which is presented to the container body, the method including the further step of severing the diaphragm from the parent sheet material around the heat seal region after heat-sealing and/or deformation.

Claim 14

A method as claimed in claim 10, wherein at least during the time that it is being deformed the diaphragm is clamped at a clamping region surrounding the heat seal region.

Claim 15

A method as claimed in claim 10, wherein the closure is of metal foil coated with a heat-sealable thermoplastics material.

Claim 16

A method as claimed in claim 14, wherein the container is of a thermoplastics material to which the thermoplastics coating of the diaphragm is directly heat-sealable.

Claim 17

A heat sterilized package of a product, comprising a shape retaining container made of a material which is softened at the temperatures employed in heat-sterilization, and charged with a product which does not inlcude a significant amount of gas, the container having a charging opening which is completely sealed by a closure of stretchable material which is substantially totally stretched beyond its elastic limit inwardly into the charging opening, the package interior having no headspace and the package being substantially gas free and substantially hydraulically solid, and in which the package has been heat sterilized while the product is contained therein, the container is undeformed by said heat sterilization, an internal corner at the seal, which corner is completely filled with the product, and around the charging opening the material of the closure curves smoothly from the periphery of the charging opening into the charging opening.

Claim 18

A heat sterilized package of a product, comprising a shape retaining container made of a material which is softened at the temperatures employed in heat-sterilization, and charged with a product which does not inlcude a significant amount of gas, the container having a charging opening which is completely sealed by a closure of stretchable material which is substantially totally stretched beyond its elastic limit inwardly into the charging opening, the package interior having no headspace and the package being substantially gas free and substantially hydraulically solid, and in which the package has been heat sterilized while the product is contained therein, the container is undeformed by said heat sterilization, an internal corner at the seal, which corner is completely filled with the product, and around the charging opening the material of the closure curves smoothly from the periphery of the charging opening into the charging opening.

Claim 19

A package of a product comprising a shape-retaining container made of a material which is softened at the temperatures employed in heat-sterilization, and charged with a product which does not include a significant amount of gas, the container having a charging opening which is completely sealed by a closure of stretchable material which is deformed inwardly into the charging opening, the package interior having no headspace and the package being substantially gas free and substantially hydraulically solid, and in which the package has been heat sterilized and the container is undeformed, an internal corner at the seal which corner is completely filled with the product, and around the charging opening the material of the closure curves smoothly from the periphery of the charging opening into the charging opening.

Claim 20

A package of a product comprising a shape-retaining container made of a material which is softened at the temperatures employed in heat-sterilization, and charged with a product which does not include a significant amount of gas, the container having a charging opening which is completely sealed by a closure of stretchable material which is deformed inwardly into the charging opening, the package interior having no headspace and the package being substantially gas free and substantially hydraulically solid, and in which the package has been heat sterilized and the container is undeformed, an internal corner at the seal which corner is completely filled with the product, and around the charging opening the material of the closure curves smoothly from the periphery of the charging opening into the charging opening.

Claim 21

A package as claimed in claim 17, wherein the closure is substantially stress free.

Claim 22

A package as claimed in claim 17, wherein the closure is heat-sealed to the container.

Claim 23

A package as claimed in claim 17, wherein the closure is a diaphragm of stretchable and relatively flexible sheet material.

Claim 24

A package as claimed in claim 17, wherein the closure is of metal foil coated with a heat-sealable synthetic polymeric thermoplastics material.

Claim 25

A package as claimed in claim 17, wherein the container is of synthetic polymeric thermoplastics material.

Claim 26

A package as claimed in claim 21, wherein the container is of a synthetic polymeric thermoplastics material to which the thermoplastics coating of the diaphragm is directly heat-sealable.

Claim 27

A package as claimed in claim 28, in which at least that part of the product nearest to the seal is liquid.

Claim 30

Apparatus for producing a package of a product which is substantially devoid of headspace and does not include a significant amount of gas, the package being formed from a container made of a material which is softened at temperatures employed in heat-sterilization and a closure formed from stretchable material spanning a mouth of the container comprising means for supporting the container with a product therein below stretchable closure material, means for reducing pressure within the container, means for heat sealing a peripheral edge of the container to an overlying portion of the stretchable material after the container pressure has been reduced thereby forming a peripheral heat seal, means for increasing pressure exteriorly of the stretchable material after the formation of the peripheral heat seal to permanently deform the stretchable material bounded by the peripheral heat seal into the container to essentially eliminate the headspace therein, means for enclosing the container and surrounding the stretchable material above and below the latter outboard of the peripheral heat seal, said enclosing means being a pair of housings, said pair of housings being disposed in superposed aligned relationship, said housings having cooperative means for clamping the stretchable material therebetween outboard of the peripheral heat seal, said cooperative clamping means being defined by opposed aligned peripheral edges of said pair of housings, said heat sealing means and container supporting means being housed in different ones of said housings and at opposite sides of the stretchable closure material, said pressure reducing means being operative after the stretchable material has been clamped by said aligned housing peripheral edges, said pressure reducing means is in fluid communication with a lowermost of said pair of housings, and knife means for severing said package outboard of the peripheral heat seal prior to the removal of the package from the enclosing means.

Claim 31

Apparatus for producing a package of a product which is substantially devoid of headspace and does not include a significant amount of gas, the package being formed from a container made of a material which is softened at temperatures employed in heat-sterilization and a closure formed from stretchable material spanning a mouth of the container comprising means for supporting the container with a product therein below stretchable closure material, means for reducing pressure within the container, means for heat sealing a peripheral edge of the container to an overlying portion of the stretchable material after the container pressure has been reduced thereby forming a peripheral heat seal, means for increasing pressure exteriorly of the stretchable material after the formation of the peripheral heat seal to permanently deform the stretchable material bounded by the peripheral heat seal into the container to essentially eliminate the headspace therein, means for enclosing the container and surrounding the stretchable material above and below the latter outboard of the peripheral heat seal, said enclosing means being a pair of housings, said pair of housings being disposed in superposed aligned relationship, said housings having cooperative means for clamping the stretchable material therebetween outboard of the peripheral heat seal, said cooperative clamping means being defined by opposed aligned peripheral edges of said pair of housings, said heat sealing means and container supporting means being housed in different ones of said housings and at opposite sides of the stretchable closure material, said pressure reducing means being operative after the stretchable material has been clamped by said aligned housing peripheral edges, said pressure reducing means is in fluid communication with a lowermost of said pair of housings, and knife means for severing said package outboard of the peripheral heat seal prior to the removal of the package from the enclosing means.

Claim 32

The apparatus as defined in claim 26 including means for moving said heat sealing means relative to its housing to form the peripheral heat seal.

Claim 33

The apparatus as defined in claim 26 including means for moving said heat sealing means relative to its housing to form the peripheral heat seal, the container further including a peripheral flange in supporting relationship upon said container supporting means, and said moving means moves said heat sealing means to effect sandwiched clamping contact of the flange between between said container supporting means and said heat sealing means whereby the peripheral heat seal includes the flange of the container.

Claim 34

The apparatus as defined in claim 26 wherein said pressure increasing means is in fluid communication with an uppermost of said pair of housings.