Patent GB-1246324-A (GB)
Title: Sterilizing method and apparatus
IPC: B65B55/10
Filed: 1968-09-17
Abstract: 1,246,324. Sterilizing packaging material. GIO & F. LLI BUITONI SANSEPOLCRO S.p.A. 17 Sept., 1968 [17 Oct., 1967], No. 44046/68. Heading B8C. [Also in Division A5] A web 1 of paper, coated in one or both sides with plastics, is subjected to the action of a fluid sterilizing medium at a pressure above atmospheric during passage through a packaging machine wherein, on passing from a feed roller 2 to a transversely aligned roller 3, the web 1 is folded along its length and is then fed over a roller 4 to a filling station at which the edges of the folded web are sealed by a device 19 to form a tube 20 into which material is deposited by a filling pipe 17. The tube 20 is transversely sealed to form individual packages, either before or after material is introduced therein, which are then separated by cutting at the seals. During passage between the rolls 2 and 3, the surfaces of the web 1 which are to form the interior of the tube 20 are enclosed by a channel 10 having upstanding side walls 11 and into which is fed, through nozzles 13 or 13a, hydrogen peroxide which is decomposed into steam and nascent oxygen by hot air fed under pressure through inlets 14. A portion of the sterilizing medium is tapped off from the channel 10 by a pipe 32 to a chamber 8 enclosing the filling pipe 17 and the sealing device 19, and the remainder is sucked off adjacent the roll 3 through a pipe 33 and recycled, in a valveadjusted ratio, by a fan 23 which introduces the sterilizing air, from atmosphere through a filter 24, into the apparatus. During passage between the rolls 3 and 4 the folded web 1 is enclosed on all sides in a channel 15 into which heated sterilized air is introduced under pressure, through a pipe 16, to prevent the ingress of unsterile air and to evaporate sterilizing fluid entrapped in the folded web 1. The chamber 8 enclosing the filling pipe 17 and sealing device 19 is fed from the pipe 32 with the sterilizing medium comprising steam and oxygen under pressure and, in addition, any steam remaining within the interior of the tube 20 is dried off by sterilized air introduced under pressure through a pipe 18. The sterilizing hydrogen peroxide is introduced to the nozzles 13 from a tank 21, via a valve 28. A sensing device 37 is arranged to close the valve 28 and to open a similar valve 28a in a pipe 22a leading to the nozzles 13a, whenever the delivery from nozzles 13 is interrupted. The air supply introduced by the fan 23 is delivered through a heater 25, where its temperature is raised to 140- 170‹ C., and one portion thereof flows through a diversion valve 27, via pipes 28, 29 and 31, to the nozzles 14, and the remainder flows, via a cooler 36, to the pipes 16 and 18 respectively supplying the channel 15 and chamber 8. In the event of the travel of the web 1 through the machine being interrupted, the valve 27 functions to divert the hot air supply from heater 25 through a cooler 38, where its temperature is reduced to 80‹ C. or lower, whereby softening of the plastics coating of the web 1 is avoided. The apparatus is initially sterilized at the commencement of production by steam introduced through a valve 41.