GB1400112A - Aseptic packaging of materials - Google Patents

Abstract

1400112 Packaging under aseptic conditions TETRA PAK DEVELOPPEMENT SA 17 July 1973 [11 Aug 1972] 33889/73 Heading B8C In an apparatus for packaging sterile goods under aseptic conditions in containers thermoformed in a web 2 and closed by a further web 3, the web 2 and the combined webs 2 and 3 co-operate with a tunnel 1 to define a chamber 4 in which a sterile atmosphere is maintained and in which the container forming, filling and closing operations are performed. The atmosphere in the chamber 4 may constitute sterilized air or a sterilizing gas maintained at a pressure higher than that surrounding the apparatus. In one embodiment the longitudinal walls of the tunnel may include inturned flanges (43), Fig. 2b (not shown), positioned under the web 2 and the combined webs 2 and 3. In two further embodiments the longitudinal edges of the web 2 and the combined webs 2 and 3 run in liquid (45), Fig. 2c (not shown), or (49), Fig. 2d (not shown), contained in longitudinally extending channels (44, Fig. 2c) or (48, Fig. 2d). In one (Fig. 2c) of these two embodiments the channels (44) are mounted to the bottoms of the longitudinal walls of the tunnel and in the other embodiment down-turned flanges thermoformed along the longitudinal. edges of the web 2 and the bottom edges of the longitudinal walls of the tunnel both clip below the surface of the liquid in the channels (48). In a fourth embodiment, Fig. 2e (not shown), a liquid or air curtain is formed between the bottom edges of the longitudinal walls of the tunnel and the margins of the web 2 and combined webs 2 and 3. Within the sterile chamber 4 the containers may be thermoformed by vacuum drawing or by a forming tool 20 in forming boxes running on an endless chain underneath the web 2 or in a forming box 19 which may include several forming cavities and is reciprocable forwards and backwards in the longitudinal direction of the web 2. A filler 22 and a closure sealing device 23 are also provided in the chamber 4. The apparatus further includes pretreatment chambers 5 and 6 which have at their openings to the surrounding atmosphere and to the sterile chamber 4 arrangements which prevent ingress of the surrounding atmosphere into the pretreatment chambers 5, 6 and the atmosphere in these chambers 5, 6 from entering the sterile chamber 4. The webs 2 and 3 are cleaned and sterilized by passing them through vats 8 and 28 of washing and/or sterilizing liquid, excess of which is removed by an air jet device, and by absorption and heating elements 10, 31 and 16, 32, and by electron spraying and/or exposure to ultraviolet light within the pretreatment chambers 5 and 6. The individual packages 41 are separated by a knife element 38.