ASEPTIC CONTAINER MOLDING METHOD AND APPARATUS AND ASEPTIC FILLING METHOD AND APPARATUS
20180186057 ยท 2018-07-05
Assignee
Inventors
Cpc classification
B29C49/4289
PERFORMING OPERATIONS; TRANSPORTING
B29C49/46
PERFORMING OPERATIONS; TRANSPORTING
B29C2049/4889
PERFORMING OPERATIONS; TRANSPORTING
B29C49/42802
PERFORMING OPERATIONS; TRANSPORTING
B29C2049/7832
PERFORMING OPERATIONS; TRANSPORTING
B29C2049/4664
PERFORMING OPERATIONS; TRANSPORTING
B29C2949/0715
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
To sterilize a container during blow molding thereof.
After a preform (1) is put in a molding die (6), the molding die (6) is clamped, and a mist or gas of a sterilizer or a mixture thereof is blasted into the preform (1), a blow molding air is blasted into the preform (1) to expand the preform (1) into a container (2) as a finished product, and the used blow molding air is discharged from the container (2) to remove the sterilizer in the container (2).
Claims
1. An aseptic container molding method, wherein after a heated preform is put in a molding die, the molding die is clamped, and a mist or gas of a sterilizer or a mixture thereof is blasted into the preform, a blow molding air is blasted into the preform to expand the preform into a container as a finished product, and the used blow molding air is discharged from the container to remove the sterilizer in the container.
2. The aseptic container molding method according to claim 1, wherein after the mist or gas of the sterilizer or the mixture thereof is blasted into the preform, a primary blow molding air is blasted into the preform to expand the preform into an intermediate molded product and at the same time sterilize an interior of the intermediate molded product, a secondary blow molding air is then blasted into the intermediate molded product to expand the intermediate molded product into the container as the finished product, and the used blow molding air is discharged from the container to remove the sterilizer in the container.
3. The aseptic container molding method according to claim 2, wherein the blow-molded container is subjected to air rinsing or aseptic water rinsing.
4. The aseptic container molding method according to claim 1, wherein a volatile substance is added to the mist or gas of the sterilizer or the mixture thereof.
5. An aseptic filling method, wherein after a heated preform is put in a molding die, the molding die is clamped, and a mist or gas of a sterilizer or a mixture thereof is blasted into the preform, a blow molding air is blasted into the preform to expand the preform into a container as a finished product, the used blow molding air is discharged from the container to remove the sterilizer in the container, and the container is removed from the molding die, filled with a content and sealed.
6. The aseptic filling method according to claim 5, wherein after the mist or gas of the sterilizer or the mixture thereof is blasted into the preform, a primary blow molding air is blasted into the preform to expand the preform into an intermediate molded product and at the same time sterilize an interior of the intermediate molded product, a secondary blow molding air is then blasted into the intermediate molded product to expand the intermediate molded product into the container as the finished product, the used blow molding air is discharged from the container to remove the sterilizer in the container, and the container is removed from the molding die, filled with the content and sealed.
7. The aseptic filling method according to claim 6, wherein the container removed from the molding die is subjected to air rinsing or aseptic water rinsing and then filled with the content and sealed.
8. The aseptic filling method according to claim 5, wherein a volatile substance is added to the mist or gas of the sterilizer or the mixture thereof.
9. An aseptic container molding apparatus, comprising a preform conveying device that conveys a preform on a first conveying path, and a molding die conveying device that conveys a molding die that molds the preform into a container on a second conveying path connected to the first conveying path, wherein after the preform heated by a heater disposed along the first conveying path is received in the molding die on an upstream part of the second conveying path, and a mist or gas of a sterilizer or a mixture thereof is blasted into the preform, a blow molding air is blasted into the preform to expand the preform into a container as a finished product on a downstream part of the second conveying path, and the used blow molding air is discharged from the container to remove the sterilizer in the container.
10. The aseptic container molding apparatus according to claim 9, wherein after the mist or gas of the sterilizer or the mixture thereof is blasted into the preform, a primary blow molding air is blasted into the preform to expand the preform into an intermediate molded product and at the same time sterilize an interior of the intermediate molded product, a secondary blow molding air is then blasted into the intermediate molded product to expand the intermediate molded product into the container as the finished product, and the used blow molding air is discharged from the container to remove the sterilizer in the container.
11. The aseptic container molding apparatus according to claim 10, wherein the blow-molded container is subjected to air rinsing or aseptic water rinsing.
12. The aseptic container molding apparatus according to claim 9, wherein a volatile substance is added to the mist or gas of the sterilizer or the mixture thereof.
13. An aseptic filling apparatus, comprising a preform conveying device that conveys a preform on a first conveying path, a molding die conveying device that conveys a molding die that molds the preform into a container on a second conveying path connected to the first conveying path, and a container conveying device that conveys the container molded in the molding die on a third conveying path connected to the second conveying path, wherein after the preform heated by a heater disposed along the first conveying path is received in the molding die on an upstream part of the second conveying path, and a mist or gas of a sterilizer or a mixture thereof is blasted into the preform, a blow molding air is blasted into the preform to expand the preform into a container as a finished product on a downstream part of the second conveying path, the used blow molding air is discharged from the container to remove the sterilizer in the container, and the container is filled with a content by a filler on the third conveying path and then sealed.
14. The aseptic filling apparatus according to claim 13, wherein after the mist or gas of the sterilizer or the mixture thereof is blasted into the preform, a primary blow molding air is blasted into the preform to expand the preform into an intermediate molded product and at the same time sterilize an interior of the intermediate molded product, a secondary blow molding air is then blasted into the intermediate molded product to expand the intermediate molded product into the container as the finished product, the used blow molding air is discharged from the container to remove the sterilizer in the container, and the container is removed from the molding die, filled with the content and sealed.
15. The aseptic filling apparatus according to claim 14, wherein the container removed from the molding die is subjected to air rinsing or aseptic water rinsing and then filled with the content and sealed.
16. The aseptic filling apparatus according to claim 13, wherein a volatile substance is added to the mist or gas of the sterilizer or the mixture thereof.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
[0038]
DESCRIPTION OF EMBODIMENTS
[0039] In the following, embodiments of the present invention will be described.
First Embodiment
[0040] As shown in
[0041] Portions of the aseptic filling apparatus from middle portion of the preform supplying machine 49 to the filling machine 4 are covered by chambers 5a and 5b, which are protection covers. Aseptic air is constantly supplied from an aseptic air supply source (not shown) into the chambers 5a and 5b, thereby keeping the interior of the chambers 5a and 5b at a positive pressure.
[0042] As shown in
[0043] Between the preform supplying machine 49 and the filling machine 4 via the blow-molding machine 3, there are provided a preform conveying device that conveys the preform 1 on a first conveying path, a molding die conveying device that conveys a molding die 6 (see
[0044] The first conveying path including the preform conveying device, the second conveying path including the molding die conveying device and the third conveying path including the container conveying device are connected to each other, and a gripper and the like (not shown) for holding the preform 1 or the bottle 2 during conveyance and passing the preform 1 or the bottle 1 between different conveying paths is provided on these conveying paths.
[0045] The preform conveying device in the preform supplying machine 49 includes a shooter 7 that successively supplies preforms 1 at predetermined intervals, a wheel 8 that receives the preforms 1 from a terminal end of the shooter 7 and conveys the preforms 1, and an endless chain 9 that extends in a horizontal direction and receives and transfers the preforms 1.
[0046] The endless chain 9 is stretched between a pair of pulleys 9a and 9b that are disposed to be opposed to each other in a horizontal plane, and the shooter 7 is connected to one 9a of the pulleys.
[0047] A large number of holding members 10 for preforms 1 like that shown in
[0048] The holding member 10 is inserted into the mouth portion 1a of the preform 1 passed from the wheel 8 to the endless chain 9 as shown in
[0049] If the holding member 10 is formed as a mandrel (not shown) instead of the spindle, the preform 1 can be supported in an inverted position during conveyance.
[0050] The endless chain 9 is surrounded by a heating furnace, and a heater 11 that emits infrared rays is provided all over an inner wall of the heating furnace.
[0051] After the preform 1 is received by the holding member 10 attached to the endless chain 9 via the shooter 7, the preform 1 travels with the endless chain 9 moving in one direction and is heated by the heater 11 to a temperature that allows blow molding. Preferably, the preform 1 is uniformly heated by rotating on its axis as the holding member 10 rotates until the temperature of the preform 1 excluding the mouth portion 1a rises to 90 C. to 130 C., which is a temperature range suitable for blow molding. The temperature of the mouth portion 1a is kept to be equal to or lower than 70 C., at which no deformation or the like occurs, so that sealing between the mouth portion 1a and a cap 22 (see
[0052] At a position where the pulley 9a at one end of the endless chain 9 is connected to the return run of the endless chain 9, a wheel 12 that receives the preform 1 heated by the heater 11 and conveys the preform 1 into the molding die 6 on the second conveying path is provided adjacent to the pulley 9a.
[0053] The blow-molding machine 3 includes the molding die conveying device on the second conveying path, and the molding die conveying device includes a wheel 13, which is connected to the wheel 12, on the second conveying path.
[0054] A plurality of molding dies 6 (see
[0055] The molding die 6 has the cavity C in the shape of the finished bottle 2, which is a container, and is divided into an upper portion 6a that corresponds to the mouth portion 1a of the bottle 2, a middle portion 6b that corresponds to a trunk portion of the bottle 2, and a molding die bottom portion 6c that corresponds to a bottom portion of the bottle 2, for example.
[0056] As required, different temperatures are set for the parts 6a, 6b and 6c of the molding die 6. For example, temperatures for the upper portion 6a and the lower portion 6c of the molding die 6 that correspond to the mouth portion 1a and the bottom portion of the bottle 2 may be set to be lower than the temperature for the middle portion 6b. The mouth portion 1a of the bottle 2 is formed when the preform 1 is yet to be molded into the bottle 2, and the mouth portion 1a may be deformed if excessive heat is applied to the mouth portion 1a. Thus, the temperature for the upper portion 6a of the molding die 6 that comes into contact with the mouth portion 1a can be set lower to prevent deformation of the mouth portion 1a. The temperature for the lower portion 6c of the molding die 6 can be set to be lower than the temperature for the middle portion 6b so that the bottom of the bottle 2 can be quickly cooled to improve the stability of the bottle 2.
[0057] The middle portion 6b of each molding die 6 is divided into two, inner and outer, parts in the radial direction of the wheel 13, the inner part stays on a certain circumference when the molding die 6 is rotating, and the outer part can move in the radial direction. A cam (not shown) is disposed on the radially outer side of the outer part of the molding die 6. The molding die 6 is closed by the cam pressing the outer part against the inner part. Closing of the molding die 6 can also be achieved by cams pressing the inner part and the outer part of the molding die against each other.
[0058] As shown in
[0059] Piping 15 for supplying primary blow molding air P1 to the preform 1 in the molding die 6 is connected to the valve V1. The preform 1 is molded into an intermediate molded product 2a by blasting the primary blow molding air P1 (see
[0060] Piping 16 for supplying secondary blow molding air P2 into the intermediate molded product 2a is connected to the valve V2. The intermediate molded product 2a is molded into the bottle 2, which is a container, by blasting the secondary blow molding air P2 (see
[0061] Piping 18 for discharging used blow molding air P1 and P2 and die clamping air described later is connected to the valve V3. A silencer 23 for reducing noise of air discharging is provided at an air outlet of the piping 18. As required, the silencer 23 is provided with a catalyst that decomposes a sterilizer such as hydrogen peroxide.
[0062] Piping 25 for supplying a mist or gas of a sterilizer or a mixture thereof to the preform 1 in the molding die 6 is connected to the valve V4.
[0063] The sterilizer effectively contains 1% or more of hydrogen peroxide. Alternatively, the sterilizer may contain one or more of ethanol, peracetic acid, ozone and a chlorine-based sterilizer or a mixture thereof.
[0064] Preferably, a volatile substance is added to the mist or gas of the sterilizer or a mixture thereof described above. The volatile substance is preferably ethanol, propanol or isopropanol, for example. If the volatile substance is added to the mist or gas of the sterilizer or a mixture thereof, the mist or gas of the sterilizer or a mixture thereof can be efficiently vaporized in the molding die 6, and no heating process for vaporizing the sterilizer is required, so that corrosion of the molding die 6 or other components due to the heating process can be avoided. The sterilizer preferably contains the added volatile substance such as ethanol as a main component and preferably contains 0.1% by weight to 35% by weight of hydrogen peroxide. In order to further reduce corrosivity and achieve a desired sterilization effect (6 Log for B. atrophaeus spores), the concentration of hydrogen peroxide is more preferably 1% by weight to 5% by weight.
[0065] Piping 19 for supplying die clamping air P0 for further firmly clamping the molding die 6 closed by the cam is connected to the valve V5.
[0066] The blow molding air P1 and P2 and a sterilizer gas G having passed through the valves V1, V2 and V4, respectively, flow to the molding die 6 through a central hole of the valve block 14. The die clamping air P0 having passed through the valve V5 flows through a block (not shown) that covers the outer part of the molding die 6 to press the outer part of the molding die 6 against the inner part. The valve V3 discharges molding air P1 and P2 blasted into the molding die 6 and the die clamping air P0 from the molding die 6 to the outside atmosphere through the central hole or the like of the valve block 14.
[0067] As shown in
[0068] The group of manifolds is in a three-stage configuration including a first manifold 51 that supplies the primary blow molding air P1 to each molding die 6, a second manifold 52 that supplies the secondary blow molding air P2 to each molding die, and a third manifold 53 that supplies the mist or gas of the sterilizer or a mixture thereof to each molding die.
[0069] As the die clamping air P0, the primary blow molding air P1 supplied from the first manifold 51 or the secondary blow air P2 described later is used.
[0070] The group of manifolds is fixed to a central shaft 20 of the wheel 13 (see
[0071] A rotary joint 17 is mounted on the central shaft 20, and piping 21 extending from a high-pressure air source (not shown), such as a compressor, is connected to the rotary joint 17. Air from the high-pressure air source is filtered by an aseptic filter (not shown) to produce aseptic air free of bacteria or the like. In addition, piping 24 extending from a vaporizer 26 that produces the mist or gas of the sterilizer or a mixture thereof is connected to the rotary joint 17.
[0072] As the vaporizer 26, one which has the structure shown in
[0073] The vaporizer 26 includes a hydrogen peroxide supplying portion 27 that is a twin-fluid spray that supplies a hydrogen peroxide solution serving as a sterilizer in the form of drops and an vaporizing portion 28 that vaporizes a spray of hydrogen peroxide supplied from the hydrogen peroxide supplying portion 27 by heating the spray of hydrogen peroxide to a temperature equal to or higher than the boiling point thereof and equal to or lower than the non-degradable temperature thereof. The hydrogen peroxide supplying portion 27 is configured to receive the hydrogen peroxide solution and compressed air from a hydrogen peroxide supply path 27a and a compressed air supply path 27b, respectively, and sprays the hydrogen peroxide solution into the vaporizing portion 28. The vaporizing portion 28 is a pipe that incorporates a heater 28a disposed between inner and outer walls thereof, and heats and vaporizes the spray of hydrogen peroxide blasted into the pipe. The vaporized hydrogen peroxide is ejected in the form of mist or gas or a mixture thereof from a nozzle 29 to the outside of the vaporizer 26.
[0074] The nozzle 29 is coupled to the piping 24 in a crossing manner. Aseptic hot air H is supplied to the piping 24 from an air source (not shown) disposed upstream of the piping 24. Thus, the mist or the like ejected from the nozzle 29 is mixed with the aseptic hot air H flowing in the piping 24 to form a hydrogen peroxide gas G, and the gas G flows to the valve block 14 through the piping 24, the rotary joint 17 and the third manifold 53.
[0075] As shown in
[0076] A driving part that makes the extension rod 30 perform the protrusion and retraction operations described above is provided for the extension rod 30. More specifically, a nut 31 is coupled to a base portion 30a at a rear end of the extension rod 30, and a feeding threaded bar 32 that extends in parallel with the extension rod 30 is screwed into the nut 31. In order to precisely achieve the protrusion and retraction operations of the extension rod 30 described above, a guide member 33 that extends in parallel with the feeding threaded bar 32 is provided. One or more rail-shaped or bar-shaped guide members 33 are provided, and the guide members 33 are slidably engaged with the base portion 30a at the rear end of the extension rod 30 or with the nut 31.
[0077] The feeding threaded bar 32 is coupled to an output shaft of a servomotor 34 at one end thereof and thus can be rotated in both forward and reverse directions.
[0078] The extension rod 30, the feeding threaded bar 32 that is the driving part therefor and the like are covered by and sealed in a housing box 35 serving as a machine casing. The housing box 35 may be divided by a partition wall (not shown) into a section that houses the extension rod 30 and a section that houses the feeding threaded bar 32.
[0079] Reference numeral 36 denotes a ventilation part formed by a filter or the like through which any air containing the mist or gas of hydrogen peroxide serving as the sterilizer or a mixture thereof in the housing box 35 is discharged to the outside of the housing box 35 as described later. Hydrogen peroxide is trapped by the filter of the ventilation part 36 and decomposed, and air alone flows out of the housing box 35. The ventilation part 36 may simply be a ventilation hole instead of the filter.
[0080] As shown in
[0081] The section up to the wheel 37 may be an independent aseptic container molding apparatus, and the aseptic bottle 2 ejected from the apparatus may be fed to the filling machine 4 by air conveyance or a belt conveyor, for example, or temporarily stored in the aseptic condition.
[0082] As shown in
[0083] A filler 46 that fills the aseptic bottle 2 with the drink a is provided along the circumference of the wheel 42. The filler 46 has a large number of filling nozzles 47 arranged around the wheel 42, and the filling nozzles 47 can rotate around the wheel 42 and fill the traveling bottle 2 with the drink a (see
[0084] The filler 46 and the capper 48 are the same as well-known devices, and detailed descriptions thereof will be omitted.
[0085] Next, operations of the aseptic container molding apparatus and the aseptic filling apparatus described above will be described along with an aseptic container molding method and an aseptic filling method.
[0086] (1) First, a process of cleaning and sterilizing the interior of the chamber 5a of the blow-molding machine 3 and a process of cleaning and sterilizing the interior of the chamber 5b of the filling machine 4 are performed.
[0087] The process of cleaning and sterilizing the interior of the chamber 5b of the filling machine 4 is performed by a well-known cleaning-in-place (CIP) system or cleaning-out-of-place (COP) system and a sterilizing-in-place (SIP) system or sterilizing-out-of-place (SOP) system, and after the cleaning and sterilizing process.
[0088] For the interior of the chamber 5a of the blow-molding machine 3, the CIP or COP as the cleaning process may be omitted, and only the SIP or SOP may be performed.
[0089] (2) In parallel with the process of sterilizing the interiors of the chambers 5a and 5b, or after the process of sterilizing the interiors of the chambers 5a and 5b, a process of molding the preform 1 into the bottle 2 is started.
[0090] First, the preform 1 is introduced into the heating furnace by the shooter 7 and the wheel 8 and conveyed by the endless chain 9 in the heating furnace. The preform 1 is heated to a temperature range suitable for molding by the heater 11 while the preform 1 is conveyed by the endless chain 9 in the heating furnace (see
[0091] (3) The heated preform 1 is put in the molding die 6 rotating around the wheel 13, and the molding die 6 is closed by the action of a cam (not shown). In addition, the valve V5 is opened, so that the primary blow molding air P1 serving as the die clamping air P0 supplied from the first manifold 51 flows to the outer part of the molding die 6 through the piping 21, the rotary joint 17 and the manifold 51. As a result, the outer part of the molding die 6 is strongly pressed against the inner part to complete clamping of the molding die (see
[0092] (4) The servomotor 34 rotates in the forward direction, thereby lowering the extension rod 30 from the interior of the housing box 35 into the preform 1 through the central hole of the valve block 14 until the extension rod 30 abuts against the bottom of the preform 1 to start expanding the preform 1 (see
[0093] (5) While the extension rod 30 is being lowered into the preform 1, the valve V4 of the valve block 14 is opened. As a result, the sterilizer gas G such as hydrogen peroxide flows into the preform 1 held in the molding die 6 through the piping 24, the rotary joint 17 and the manifold 53 in the form of gas or mist or a mixture thereof. Bacteria in the preform 1 are killed by the sterilizer flowing into the preform 1. The part of the extension rod 30 in the preform 1 is also sterilized.
[0094] Once a predetermined amount of sterilizer gas G is supplied into the preform 1, the valve V4 is closed to stop the supply of the sterilizer into the preform 1.
[0095] (6) At the same time as the valve V4 being closed, the valve V1 is opened, and the high-pressure air serving as the primary blow molding air P1 is blasted into the preform 1 held in the molding die 6 through the piping 21, the rotary joint 17 and the manifold 51. The pressure of the primary blow molding air P1 is set to be lower than the high-pressure air by the action of a throttle valve (not shown) or the like.
[0096] Under the pressure of the blasted primary blow molding air P1 and the pressure exerted by the lowering extension rod 30, the preform 1 is expanded into the intermediate molded product 2a as shown in
[0097] (7) Once the preform 1 is expanded into the intermediate molded product 2a having a predetermined size, the valve V1 is closed, and at the same time the valve V2 is opened so that a predetermined amount of high-pressure air serving as the secondary blow molding air P2 is blasted into the intermediate molded product 2a held in the molding die 6 through the piping 21, the rotary joint 17 and the manifold 52.
[0098] The blasting of the secondary blow molding air P2 causes expansion of the intermediate molded product 2a in the molding die 6 into the bottle 2 (see
[0099] (8) Once a predetermined amount of secondary blow molding air P2 is supplied to the intermediate molded product 2a, the valve V2 is closed to stop the supply of the secondary blow molding air P2.
[0100] (9) After the intermediate molded product 2a in the molding die 6 is expanded into the bottle 2 as shown in
[0101] As a result, the used blow molding air P1 and P2 in the bottle 2 is discharged to the outside of the molding die 6 through the piping 18. In this step, the silencer 23 prevents occurrence of discharging noise. By discharging the used blow molding air P2 from the container 2, the sterilizer such as hydrogen peroxide in the container 2 is removed (see
[0102] The discharged used blow molding air P2 can also be reused as the blow molding air P1.
[0103] (10) The servomotor 34 rotates in the reverse direction, thereby lifting the extension rod 30 from the interior of the molding die 6 to the interior of the housing box 35 (see
[0104] (11) Once the molding of the bottle 2 in the molding die is completed, the molding die 6 is opened, and the finished bottle 2 is removed from the molding die 6 by the gripper (not shown) disposed around the wheel 37 (see
[0105] (12) The bottle 2 is passed to the wheels 40, 41, 42, 43, 44 and 45 in the filling machine 4 and travels in the filling machine 4.
[0106] (13) In the filling machine 4, while the bottle 2 is traveling around the wheel 42 provided with the filler 46, the bottle 2 is filled with the sterilized content a, such as a drink, from the nozzle 47 in the filler 46 (see
[0107] The cap sterilizing apparatus is a well-known apparatus, and detailed descriptions thereof will be omitted.
[0108] (14) The opening of the valve V4 in the step (5) described above and the opening of the valve V1 in the step (6) described above may be performed at the same time.
[0109] In that case, as shown in
[0110] Next, specific sterilization conditions and sterilization effects in the case where hydrogen peroxide is used as the sterilized in the step (5) described above will be described.
[0111] The inventor measured the effect of sterilization and the concentration of residual hydrogen peroxide on B. atrophaeus pores on the inner surface of a PET bottle having a volume of 500 milliliters (mL). The results are as shown in Tables 1 and 2 below.
TABLE-US-00001 TABLE 1 DURATION OF SPRAYING OF HYDROGEN PEROXIDE GAS: 0.5 SECONDS CONCENTRATION CONCENTRATION STERILIZATION OF H.sub.2O.sub.2 OF RESIDUAL EFFECT GAS (mg/L) H.sub.2O.sub.2 (ppm) (LRV) 4.4 N.D 0.5 8.8 0.01 2.8 17.5 0.07 5.2
TABLE-US-00002 TABLE 2 DURATION OF SPRAYING OF HYDROGEN PEROXIDE GAS: 2.0 SECONDS CONCENTRATION CONCENTRATION STERILIZATION OF H.sub.2O.sub.2 OF RESIDUAL EFFECT GAS (mg/L) H.sub.2O.sub.2 (ppm) (LRV) 4.4 N.D 3.3 8.8 0.03 5.1 17.5 0.1 >6.0
[0112] Evaluation was conducted as follows.
Sterilization effect(Log Reduction Value)=Log(adhering bacteria count/surviving bacteria count)
[0113] Bacteria adhering to the inner surface of the bottle: B. atrophaeus ATCC9372
[0114] Method of measuring the concentration of residual hydrogen peroxide: oxygen electrode method (N.D.; <0.01 ppm)
[0115] Sterilization step: after the preform was heated, hydrogen peroxide gas was sprayed to the preform, and then blow molding was performed. For comparison, the hydrogen peroxide gas was sprayed for two different periods: 0.5 seconds and 2 seconds.
[0116] As is obvious from Table 1, when the duration of spraying of the hydrogen peroxide gas was 0.5 seconds, a sterilization effect of 5 LRV was ensured if the concentration of the hydrogen peroxide gas was set at 17.5 mg/L. When the duration of spraying of the hydrogen peroxide gas was 2 seconds, a sterilization effect of 5 LRV was ensured if the concentration of the hydrogen peroxide gas was set at 8.8 mg/L.
[0117] As can be seen from the test result described above, if the duration of spraying of the hydrogen peroxide gas is shorter than 0.5 seconds, the concentration of the hydrogen peroxide gas needs to be set higher, so that the hydrogen peroxide is more likely to condense, and it is more difficult to feed the hydrogen peroxide gas into the preform through the valve block. In order to achieve an adequate sterilization effect by introducing the hydrogen peroxide gas to the preform heated to 100 C. or higher, the conditions shown in Tables above are appropriate.
[0118] On the other hand, the concentration of the residual hydrogen peroxide in the bottle was equal to or lower than 0.1 ppm under all the conditions shown in Tables 1 and 2 and thus was lower than 0.5 ppm, which is the level defined by FDA. Furthermore, if an air rinsing process (70 C. or higher, 2.3 seconds or longer) described below with regard to the second embodiment was additionally performed after blow molding, the value of the concentration of the residual hydrogen peroxide was equal to or lower than the detection limit (N.D.).
Second Embodiment
[0119] As shown in
[0120] One or more air rinsing nozzles 54 are disposed around the wheel 39, for example. The air rinsing nozzle 54 may be disposed around the wheel 37, 40 or 41 instead of, or in addition to, the wheel 39.
[0121] In addition, a conveying duct (not shown) filled with positive-pressure aseptic air may be provided around the wheel 39 or the like, and aseptic air may be blasted into the bottle 2 by passing the bottle 2 through the conveying duct. The bottle 2 can also be air-rinsed in this way.
[0122] When the bottle 2 molded in the molding die 6 in the blow-molding machine 3 is traveling around the wheel 39, as shown in
[0123] The aseptic air N may be hot air. In that case, the hydrogen peroxide remaining in the bottle 2 is activated, so that the effect of sterilization of the bottle 2 is improved.
[0124] As shown in
[0125] Reference numeral 57 denotes a gripper that holds the mouth portion 1a of the bottle 2 during conveyance. Instead of conveying the bottle 2 with the gripper, a support ring may be attached to the mouth portion 2a of the bottle 2 and put on two guide rails, and the bottle 2 may be conveyed by the air for air rinsing. In that case, the interior of the conveying duct is desirably sterilized by the sterilizer in advance.
[0126] As shown in
[0127] The mechanism for inverting the bottle 2 has a well-known structure, so that detailed descriptions thereof will be omitted.
[0128] In the second embodiment, parts that are the same as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and redundant descriptions thereof is omitted.
REFERENCE SIGNS LIST
[0129] 1 preform [0130] 2 container (bottle) [0131] 2a intermediate molded product [0132] 6 molding die [0133] 11 heater [0134] 46 filler [0135] P1 primary blow molding air [0136] P2 secondary blow molding air [0137] a content