EP1975116A1 - Method of filling a retractable package - Google Patents

Abstract

The method involves filling a retractable bi-oriented polyethylene terapthalate container i.e. bi-oriented poly ethylene terapthalate bottle, with a liquid product (9) at high temperature, and cooling outer walls (5) of the container during the filling step by a cooling unit (7). The container is closed in a sealed manner. The walls of the container are cooled during the closing step. The container is passively retracted after the closing step. The walls of the container are cooled after the retraction step. Independent claims are also included for the following: (1) a device for packaging liquid product in a plastic bi-oriented polyethylene terapthalate container (2) a plastic bi-oriented polyethylene terapthalate container implementing a method.

Description

Field of the invention

The invention relates to a method of packaging a liquid product in a shrinkable package. The invention describes the packaging of a product at high temperature in a plastic container which shrinks under the effect of said high temperature. The method applies in particular to the packaging of a product at more than 60 ° C in a PET bottle that has not been heat-fixed.

State of the art

Polyethylene terephthalate (PET) bottles are used in many fields because of their excellent properties: strength, lightness, transparency, organoleptic. These bottles are manufactured at high speed by bi-axial stretching of a preform in a mold.

However, although these bottles have many advantages, they have the disadvantage of deforming when their temperature is above 60 ° C. Packaging a product at high temperature (85 ° C) in these bottles causes deformations such that said bottles become unfit for consumption. Several methods are described in the prior art in order to overcome the aforementioned drawback and allow the hot filling of PET bottles.

Thermoplating is considered to be the most efficient method for improving the heat resistance of bi-oriented PET bottles. The principle of this process, widely used on the market, is to heat treat the walls of the bottle to increase crystallization and thus improve the molecular stability at high temperature. This principle can be broken down into several methods and thermo-fixing devices described in the prior art. An important advantage of thermo-fixing processes is not to change the packaging processes, the thermo-fixing of the bottle being made during the manufacture of said bottle.

However, the bottles having undergone heat treatment to allow the conditioning of a liquid at high temperature, have several disadvantages.

A first drawback lies in the fact that only specific grades of polyethylene terephthalate can be used. These grades are more difficult to produce and generate additional packaging costs.

A second disadvantage is related to the decrease in the production rate of the bottles because the thermo-fixing process slows down the blowing cycle.

A third drawback is related to the weight of these bottles. When a bottle is filled with a hot liquid, it results after cooling a negative pressure inside the bottle; said negative pressure having the effect of randomly deforming the walls of the bottle. The most common method for dealing with the negative pressure in the bottle is the addition of compensation panels that allow the bottle to be deformed in a controlled manner. However, bottles with compensation panels are stiffer and therefore heavier. This results in an excess of material which is not strictly necessary for the good preservation of the product. In addition, the compensation panels are detrimental to the aesthetics of the packaging, which makes it less attractive to the consumer.

Patent applications W02004106175 and W02005002982 propose a design of the bottom of the bottle which can be deformed and avoids the use of lateral compensation panels.

The patent application FR2432991 proposes a method of filling a PET bottle which avoids the use of bottles having undergone thermo-fixing. This process consists in cooling the outer walls of the bottle in order to to avoid any distortion of the bottle during the conditioning cycle. According to this method, the cooling of the outer walls of the bottle can be interrupted when it is no longer necessary to prevent deformation of said bottle. This method makes it possible to avoid deformations of the bottle during filling. However, this method does not make it possible to eliminate the compensation panels to cope with the negative pressure in the bottle after cooling.

The patent US5251424 also proposes a method of packaging a PET bottle which avoids the use of bottles having undergone thermo-fixing. This process involves filling the bottle with a high temperature liquid, and adding a dose of liquid nitrogen before closing. The vaporization of the nitrogen generates a pressure in the bottle which prevents its retraction. In addition, this method avoids lateral compensation panels, because the nitrogen maintains a sufficient pressure in the bottle to compensate for the change in volume of the liquid. Theoretically, the process described in the patent US5251424 should allow the use of conventional PET bottles as well as cost reduction. However, in practice this process is very difficult to implement. The overpressure generated immediately after closing the bottle whose walls are at high temperature causes an immediate and undesired deformation of the package.

To overcome the disadvantages of the patent US5251424 , the patent US6502369 proposes a similar process, but with a filling of the bottle in the cavity of a mold. This process involves introducing the bottle into the cavity of a mold, filling the bottle with a liquid at high temperature, and adding a dose of liquid nitrogen before closing. The vaporization of the nitrogen pressurizes the wall of the package against the wall of a cooled mold. This method makes it possible to obtain conventional bottles filled at high temperature, however the complexity of the packaging machine which consists of filling each bottle in the cavity of a mold makes this process difficult to use.

The processes proposed in the prior art all have one thing in common, which is to avoid the shrinkage of the package under the effect of temperature. The volume of the packaging is unchanged before and after packaging.

General presentation of the invention

Unlike the methods proposed in the prior art, the principle of the invention is to exploit the shrinkage properties of the package during the conditioning phase and consequently leads to a change in the volume of said package. The volume of the filled package according to the invention is smaller after conditioning.

The process according to the invention consists in using, in a controlled manner, the shrinkage properties of the packages when they are filled at high temperature (generally 85 ° C. for PET bottles). This method is advantageous because it makes it possible on the one hand to use packages that have not undergone prior heat treatment and it makes it possible to avoid or limit the creation of a negative relative pressure in the package after cooling.

The process described in the invention allows packaging that shrinks when they are subjected to the high product conditioning temperature. These plastic packages have a molecular orientation that shrinks at said high temperature. The invention is particularly applicable to the filling of bioriented PET containers such as bottles. The invention also applies to the high temperature filling of plastic packaging made from films, said films shrinking under the effect of said high temperature.

The method according to the invention also makes it possible to generate a positive relative pressure inside a retractable package. The invention consists in retracting a filled and sealed package by heating the wall of said package.

The process according to the invention makes it possible to improve the grip and the vertical compressive strength of thin-walled packagings.

The invention will be better understood with the aid of the following figures:

The Figures 1 to 11 describe a first embodiment of the invention.

The Figures 1 and 2 describe the general concept of the first embodiment of the invention.

The figure 1 shows the packaging immediately after filling and corking, the product inside the packaging being at high temperature.

The figure 2 shows the packaging at the end of the product packaging process. The volume of the package is lower due to shrinkage of the package.

The Figures 3 to 8 present the different steps of the process.

The figure 3 shows a package before filling.

The figure 4 illustrates the filling of the product at high temperature in the package.

The figure 5 shows the closure of the package tightly.

The figure 6 illustrates the retraction of the package, the product being at high temperature. The pressure inside the package compresses the volume of gas at the headspace.

The figure 7 shows the cooling of the packaging and the return to ambient temperature of the product.

The figure 8 shows the package cooled to room temperature. The expansion of the volume of gas at the headspace compensates for the thermal contraction of the product.

The figure 9 illustrates local cooling of the package during the packaging process.

The Figures 10 and 11 illustrate the hot filling of a package made from a film that shrinks at said high temperature.

The figure 10 shows the packaging just after filling the product at high temperature and sealing.

The figure 11 illustrates the geometry of the retracted package.

The Figures 12 and 13 illustrate a second embodiment of the invention which consists in generating an overpressure in a shrink packaging at high temperature and filled at low temperature.

The figure 12 illustrates the heating to create a local retraction of the walls of the package and thus generate a pressure in the package.

The figure 13 shows that the volume of the package after retraction is lower than the initial volume.

Detailed exposition of the invention

The invention involves using the shrinkage properties of a package when heated at high temperature. In the disclosure of the invention, the term "high temperature" defines a temperature to initiate the retraction of the package; and by contrast the term "low temperature" defines a temperature below the retraction temperature.

The shrinkage properties of a package strongly depend on the manufacturing processes and more precisely the molecular orientation induced during said manufacture. For example, a package such as a PET bottle made by bi-stretching a preform in a mold, shrinks strongly when heated at high temperature. Other packages, such as packaging made from film may also have similar shrink properties.

The first embodiment of the invention is to use the retraction of the package during the packaging of a product at high temperature, said product having the effect of heating the walls of the package and generate the retraction. The key point of the invention is to use in a controlled manner the shrinkage of the package to limit deformation and at least partially remedy the negative pressure that usually appears in the packaging after cooling.

The general principle of the invention is presented from the Figures 1 and 2 .

The figure 1 shows the initial geometry of the package 1 comprising a neck 4, a cylindrical body 5, and a bottom 6. The package has a strong shrinkage of its walls when heated at high temperature. The figure 1 shows the package 1 filled with a product at high temperature 9, and sealed with a cap 8. The packaging is also filled with gas 10 at the head space, said gas can be air. The filling level 11 defining the relative volume of product at high temperature and gas inside the package at the time of its closure, is defined precisely. Before sealing the package, it is generally preferable to avoid retraction of said package. Therefore, when the retraction of the package is fast, it may be advantageous to implement means for blocking the retraction before said hermetic closure.
The figure 2 shows package 1 and its contents after cooling to room temperature. The packaging shrunk when packaging the product at high temperature. The volume variation of the packaging is schematically represented by the height variation 3 of the package. The variation in volume can be related to a variation in height, a variation in diameter or a change in geometry. In all cases, the volume variation is created by the retraction of the walls of the package. Some parts of the packaging are not retracted as the neck 4 for example which seals with the cap. The figure 2 also shows the volume of product 9 inside the package; said volume having decreased due to the contraction of the product 9 during cooling to room temperature. According to the invention, the shrinkage of the walls of the package after hermetic closure at least partially compensates for the contraction of the product during cooling. It is often advantageous to shrink the package sufficiently to generate a relative pressure inside the package greater than or equal to zero when the product is at room temperature. Thus, the use of packaging with compensation panels is no longer necessary.

The Figures 3 to 8 illustrate the filling of PET packaging, and describe each step of the process.

The figure 3 is a PET package 1 comprising a neck 4, side walls 5 and a bottom 6. This packaging has a strong molecular orientation at its walls, so that said walls shrink at high temperature. In the case of PET packaging made by bi-axial stretching, said high temperature, which corresponds to the temperature at which the molecular mobility becomes sufficient to allow retraction, is greater than 60 ° C. Typically, hot fill temperatures are at least 85 ° C to ensure sufficient storage properties. At these temperatures the walls of the PET packaging retract strongly and quickly.

The figure 4 represents the filling of a product 9 at high temperature in the package 1 which retracts at said high temperature. In general, the cooling of the outer walls of the package 1 is necessary in order to avoid shrinkage of the package during said filling. Means 7 cool the outer wall of the package at the neck 4, the side walls 5 and the bottom 6. In some cases, partial cooling of the walls of the package is sufficient. For example, the cooling of the outer wall of the bottle can be done with a low temperature fluid projected onto the package. The filling is done quickly to avoid the shrinkage of the packaging under the effect of temperature. The package 1 is not completely filled with the product 9 in order to leave a sufficient volume of gas in the headspace. This gas is generally air, however it may be advantageous in some cases to use specific gases such as nitrogen or carbon dioxide. The addition of specific gases in the headspace is usually done immediately after filling and before sealing the package.

The figure 5 illustrates the hermetic closure of the package 1 after filling the product 9 at high temperature. The filling level 11 at the time of hermetic sealing defines the filling ratio, that is to say the relative proportions of the product 9 and the gas 10 in the package. The degree of filling plays an important role in the invention because it defines the residual pressure in the package after cooling. This aspect will be better understood after the complete description of the different steps of the process. During the hermetic sealing step of the illustrated package figure 5 it is often best to continue to cool the outer wall of the package. The closing operation consists in the application of a cap 8 on the neck 4 to seal the package 1. At the time of closure, the relative pressure inside the package is zero. Cooling means 7 prevent the temperature rise too high of the package and its retraction. The illustrated closing step figure 5 is performed quickly according to known methods. For example, the closure can be made by corking or welding.

The figure 6 illustrates the key step of the packaging process whereby the package retracts in a controlled manner. In this step, the walls of the package shrink under the effect of temperature and create a decrease in the volume of said package. It follows a rise in pressure in the package which is hermetically sealed. This rapid increase in pressure has the effect of compressing the volume of gas inside the package.

The retraction step of the illustrated package figure 6 is initiated when the product is still hot enough to create the retraction. Generally, the shrinkage is done immediately after closing when the product is still at high temperature. When the temperature of the product is too high, it is desirable to cool the product and the package to a suitable shrink temperature. Indeed, a retraction temperature that is too high results in unwanted deformations of the package. For example, when filling PET packaging at 100 ° C, it may be advantageous to carry out the shrinkage at 80 ° C. It is therefore necessary to cool the product and the package up to 80 ° C before making the retraction.

The shrinkage is initiated at a high enough temperature to generate a pressure inside the package, and low enough to avoid unwanted deformations of said package. For PET packaging, this temperature is generally between 65 ° C and 100 ° C; however, a shrink temperature of between 75 ° and 90 ° C is advantageous.

The retraction of the packaging is usually weak and hardly visible to the naked eye. The shrinkage depends on the package, the fill rate, the temperature and the shrink time. The rate of shrinkage has a direct influence on the residual pressure, that is to say on the relative pressure in the package after cooling. Generally, a liquid product filled at high temperature shrinks by about 2% to 5% by cooling. For example, water cooling from 85 ° C to 20 ° C decreases its volume by about 3%. The decrease in volume depends on the temperature variation as well as the properties of the product. Theoretically, shrinkage of the package equal to the change in volume of the product leads to zero residual pressure. When the retraction of the package is greater than the change in volume of the product, the residual pressure is positive; and conversely when the shrinkage of the package is smaller than the change in volume of the product, the pressure residual is negative. In practice, the temperature of the gas during the hermetic closure of the packaging can influence the residual pressure. It is advantageous to trap a low temperature gas at the time of hermetic sealing of the package.

The geometry of the package has a direct influence on the volume shrinkage of said package. It has been observed that a small volume and thick package is favorable for generating a high shrinkage pressure.

The conditions of manufacture of said packaging also have a great influence on the shrinkage. For PET packaging, it has been observed that a low bi-axial stretching temperature makes it possible to obtain packages which shrink strongly under the effect of temperature. Conversely, a high biaxial stretching temperature makes it possible to obtain lower shrinkage forces. The stretching temperature optimizes the strength and speed of shrinkage of the package.

The degree of filling, defined by the ratio of the volume of product to the volume of the package at the time of sealing, has an influence on the retraction of the package. When the filling ratio is too high, the package shrinks little and there is a residual negative pressure in the package. Conversely, when the filling ratio is too low, the packaging shrinks strongly and undesired strains of said packaging result. The filling rate must be adjusted according to the desired residual pressure. Usually the filling ratio is chosen between 85% and 98%, and preferably between 90% and 96%.

The figure 6 illustrates the retraction mechanism. Under the effect of the high temperature of the product 9, the package retracts and compresses the volume of gas 10 located in the headspace. The compression of the gas is visualized by the change of the filling level 11. The shrinkage speed of the package is generally quite fast and depends on the shrinkage temperature. Preferably the retraction time is less than 5 minutes and preferably less than 3 minutes. Retraction is initiated when the product is still at high temperature.

The figure 7 shows the step of cooling the package and its contents to room temperature. Means 7 cool the outer wall of the package. For example, water is sprayed on the package to cool it, or the package can be immersed in a cold water bath. It is often advantageous to rapidly cool the package to the molecular stability temperature of said package, i.e. the temperature at which the package does not shrink. For a bi-axially stretched PET package this temperature is about 60 ° C. From this temperature, the packaging can be cooled more slowly by natural convection with the ambient air.

The figure 8 shows the package after cooling to room temperature. Cooled packaging is distinguished from pre-filled packaging shown figure 3 ; said volume of the package having decreased because of its retraction during packaging. In a preferred embodiment, the relative pressure inside the package is greater than or equal to zero. According to this preferred embodiment, the packaging does not include compensation panels; said panels being useless since the pressure inside the package is positive or zero.

In the disclosure of the invention, the package is always shown with the neck 4 upwards. It is common to spill the package after the hermetic closure of the latter to perform a heat treatment of the entire inner surface of the package. The overturning of the packaging allows the heat treatment of the inner surface of the neck 4 and the plug 8; said inner surface being in contact with the product at high temperature during overturning. The heat treatment makes it possible to kill the germs that may remain on the inner wall of the packaging and ensures optimal preservation of the product.

The invention makes it possible to fill high-temperature packagings with great precision and reproducibility. Reproducibility requires the use of packaging produced identically. For manufactured PET packaging by blowing a preform, it is important for example to control the blowing temperature which has a great influence on the shrinkage properties. When packaging the product, it is important to proceed in the same way with all bottles. The control of the manufacturing process of the packaging and their filling ensures a production of great stability.

The invention makes it possible to fill at 100 ° C PET packaging without heat-fixing. Packaging a product at 100 ° C may require optimized cooling means during the steps of filling and sealing the package. According to the invention, the package can be filled and retracted at 100 ° C; or the package can be filled at 100 ° C and retracted at a lower temperature, such as 85 ° C.

When the packaging is made at a particularly high temperature, it may be advantageous to use packaging which only some parts have undergone a heat treatment. It is advantageous, for example, to use a PET packaging of which only the neck is crystallized in order to avoid shrinkage of this part of the package.

More generally, it may be advantageous to create packages having preferred retraction zones. These preferred retraction zones can be created during manufacture of said package by generating a stronger molecular orientation in said retraction zones. For blow-molded PET packaging, preferred shrink zones can be created by varying the draw ratio and the draw temperature. A low blow-up temperature or a high draw ratio makes it possible to increase the shrinkage.

The figure 9 illustrates another method for having preferred retraction zones. This method consists of blocking the retraction of certain parts of the package during the retraction step. Means 7 cool the party lower the packaging and thus avoid the retraction of this part of the package. The top of the uncooled package retracts.

The first embodiment of the invention is particularly suitable for filling at high temperature bi-oriented PET packaging such as bottles. The invention makes it possible to dispense with the use of bottles having undergone a heat-fixing treatment. It allows the use of bottles without compensation panels as well as filling at temperatures as high as 100 ° C. The invention also allows the use of thin-walled bottles, said thin wall being less than 0.3 mm. Finally, the invention makes it possible to obtain bottles with a slight residual internal pressure; said pressure being generated by shrinkage of the package during the hot filling process.

The invention can be used for high temperature filling of a wide variety of packages that shrink at said high temperature. Packaging made from films can be used. The Figures 10 and 11 show the conditioning of a high temperature liquid in a packaging made from a film.

The figure 10 illustrates the hermetic sealing step of the package. The package 1 comprises a tubular body 5 connected to a neck 4 and a bottom 6; said tubular body 5 being made from a film which shrinks under the effect of said high temperature. The film having one or more layers has a molecular orientation sufficiently large to generate the shrinkage properties. Said film has not been heat-fixed which suppresses the shrinkage properties. The connection between the film 5 and the ends 4 and 6 can be made by welding. Said ends 4 and 6 generally have a greater thickness than the tubular body 5 and can be made by molding. According to a preferred embodiment, the ends 4 and 5 respectively forming the neck and the bottom of the package do not shrink under the effect of said high temperature. The package 1 is filled with a product at high temperature 9 and sealed with a cap 8. A volume of gas 10 is trapped at the head space during sealing. As illustrated by figure 10 , the outer wall of said package is not necessarily cooled during hot filling and sealing. Cooling may be necessary to limit or prevent retraction of the package prior to sealing.

The figure 11 illustrates the package 1 retracted after cooling to room temperature of the package and its contents. Only the tubular body 5 has shrunk under the effect of high temperatures. After cooling, the residual relative pressure in the package 1 is positive or zero. A slight overpressure in the package is favorable to improve the handling of said package and its resistance to vertical compression.

The Figures 12 and 13 illustrate the second embodiment of the method of using the shrink properties to pressurize a filled package at a temperature below the shrink temperature. Pressurizing the packaging after filling is particularly useful when said packaging has walls of thin thickness. The conventional method for generating this pressure is to add after filling a gas such as nitrogen in the headspace. The change of state of the gas generates a slight overpressure which improves the strength of the package and facilitates its use. The invention makes it possible to generate this excess pressure without the addition of a specific gas in the headspace.

The figure 12 shows the package 1 filled with a product 9 at low temperature, said low temperature being lower than the retraction temperature of the package. A cap 4 seals the package 1. A volume of air 10 is enclosed in the package and is located at a retractable area of the package. Means 12 heat at least said retractable zone to slightly reduce the volume of said package and slightly compress the volume of air 10.

The figure 13 illustrates the retracted package. The decrease in height 3 serves to illustrate the variation in volume of said package. The volume of air 10 in the packaging has decreased, indicating that the air is slightly compressed. The invention is particularly advantageous for pressurizing PET packaging such as bottles.

The invention of using the retraction properties of the package during packaging requires a package design that takes into account shrinkage of the package during packaging. The packaging must be designed so that the final volume corresponds to the desired volume. Generally the shrinkage of the package is between 1% and 20%, and preferably this shrinkage is between 3 and 15%.

Example 1

The bottle has a weight of 24 grams, and its bottom is petaloid. Its initial volume is 543.2 ml. After filling at 85 ° C according to the procedure below, its volume becomes 508.7 ml. The bottle shrank by 6.35% during filling. After cooling, the relative pressure inside the bottle is slightly positive.

1. 1. Mise à disposition d'une bouteille vide
2. 2. Rinçage de la bouteille
3. 3. Transfert de la bouteille sur la station d'alimentation
4. 4. Début du refroidissement de la paroi extérieure de la bouteille par aspersion avec de l'eau à 15°C
   1. a. Remplissage de la bouteille avec de l'eau à 85°
      • i. Durée du remplissage : 4 secondes
      • ii. Volume de remplissage : 92% du volume initial soit 499.7 ml.
   2. b. Transfert sur la station de fermeture
      1. i. Durée : 1s
   3. c. Fermeture étanche de la bouteille
      1. i. Durée du bouchonnage : 1s
5. 5. Fin du refroidissement de la paroi extérieure de la bouteille
6. 6. Rétraction de la bouteille à l'air libre
   1. i. Phase de rétraction et traitement thermique
   2. ii. température de l'air ambiant : 20 °C
   3. iii. Durée : 2 minutes
7. 7. Refroidissement rapide de la bouteille
   1. i. Refroidissement par aspersion avec de l'eau à 15°C jusqu'à retour à température ambiante de l'emballage et son contenu

The bottle is filled according to the following procedure.

1. 1. Provision of an empty bottle
2. 2. Rinsing the bottle
3. 3. Transfer of the bottle to the Power Station
4. 4. Start of cooling of the outer wall of the bottle by spraying with water at 15 ° C
   1. at. Filling the bottle with 85 ° water
      • i. Filling time: 4 seconds
      • ii. Filling volume: 92% of the initial volume is 499.7 ml.
   2. b. Transfer to the closing station
      1. i. Duration: 1s
   3. vs. Watertight closure of the bottle
      1. i. Duration of corking: 1s
5. 5. End of the cooling of the outer wall of the bottle
6. 6. Extraction of the bottle in the open air
   1. i. Retraction phase and heat treatment
   2. ii. ambient air temperature: 20 ° C
   3. iii. Duration: 2 minutes
7. 7. Fast cooling of the bottle
   1. i. Cooling by spraying with water at 15 ° C until the packaging is returned to ambient temperature and its contents

Example 2

The bottle has a weight of 37.4 grams, and its bottom is petaloid. Its initial volume is 1064.2 ml. After filling at 85 ° C according to the procedure below, its volume becomes 1012.1 ml. The bottle was retracted 4.9% during filling. After cooling, the relative pressure inside the bottle is slightly positive.

1. 1. Mise à disposition d'une bouteille bouteille vide
2. 2. Rinçage de la bouteille
3. 3. Transfert de la bouteille sur la station d'alimentation
4. 4. Début du refroidissement de la paroi extérieure de la bouteille par aspersion avec de l'eau à 15°C
   1. a. Remplissage de la bouteille avec de l'eau à 85°
      • i. Durée du remplissage : 8 secondes
      • ii. Volume de remplissage : 92% du volume initial soit 979,1 ml
   2. b. Transfert sur la station de fermeture
      1. i. Durée : 1s
   3. c. Fermeture étanche de la bouteille
      1. i. Durée du bouchonnage : 1s
5. 5. Fin du refroidissement de la paroi extérieure de la bouteille
6. 6. Rétraction de la bouteille à l'air libre
   1. i. Phase de rétraction et traitement thermique
   2. ii. température de l'air ambiant : 20 °C
   3. iii. Durée : 3 minutes
7. 7. Refroidissement rapide de la bouteille
   1. i. Refroidissement par aspersion avec de l'eau à 20°C jusqu'à retour à température ambiante de l'emballage et son contenu

The bottle is filled according to the following procedure.

1. 1. Provision of an empty bottle
2. 2. Rinsing the bottle
3. 3. Transfer of the bottle to the Power Station
4. 4. Start of cooling of the outer wall of the bottle by spraying with water at 15 ° C
   1. at. Filling the bottle with 85 ° water
      • i. Duration of filling: 8 seconds
      • ii. Filling volume: 92% of the initial volume is 979.1 ml
   2. b. Transfer to the closing station
      1. i. Duration: 1s
   3. vs. Watertight closure of the bottle
      1. i. Duration of corking: 1s
5. 5. End of the cooling of the outer wall of the bottle
6. 6. Extraction of the bottle in the open air
   1. i. Retraction phase and heat treatment
   2. ii. ambient air temperature: 20 ° C
   3. iii. Duration: 3 minutes
7. 7. Fast cooling of the bottle
   1. i. Cooling by spraying with water at 20 ° C until the packaging is returned to ambient temperature and its contents

Example 3

The bottle has a weight of 24 grams, and its bottom is petaloid. Its initial volume is 543.2 ml. After filling at 95 ° C according to the procedure below, its volume becomes 489.5 ml. The bottle was retracted 9.89% during filling. After cooling, the relative pressure inside the bottle is slightly positive.

1. 1. Mise à disposition d'une bouteille vide
2. 2. Rinçage de la bouteille
3. 3. Transfert de la bouteille sur la station d'alimentation
4. 4. Début du refroidissement de la paroi extérieure de la bouteille par aspersion avec de l'eau à 5°C
   1. a. Remplissage de la bouteille avec de l'eau à 95°
      • i. Durée du remplissage : 4 secondes
      • ii. Volume de remplissage : 92% du volume initial soit 499.7 ml.
   2. b. Transfert sur la station de fermeture
      1. i. Durée : 1s
   3. c. Fermeture étanche de la bouteille
      1. i. Durée du bouchonnage : 1s
5. 5. Fin du refroidissement de la paroi extérieure de la bouteille
6. 6. Rétraction de la bouteille à l'air libre
   1. i. Phase de rétraction et traitement thermique
   2. ii. température de l'air ambiant : 20 °C
   3. iii. Durée : 1 minute
7. 7. Refroidissement rapide de la bouteille
   1. i. Refroidissement par aspersion avec de l'eau à 20°C jusqu'à retour à température ambiante de l'emballage et son contenu

The bottle is filled according to the following procedure.

1. 1. Provision of an empty bottle
2. 2. Rinsing the bottle
3. 3. Transfer of the bottle to the Power Station
4. 4. Start of cooling of the outer wall of the bottle by spraying with water at 5 ° C
   1. at. Filling the bottle with 95 ° water
      • i. Filling time: 4 seconds
      • ii. Filling volume: 92% of the initial volume is 499.7 ml.
   2. b. Transfer to the closing station
      1. i. Duration: 1s
   3. vs. Watertight closure of the bottle
      1. i. Duration of corking: 1s
5. 5. End of the cooling of the outer wall of the bottle
6. 6. Extraction of the bottle in the open air
   1. i. Retraction phase and heat treatment
   2. ii. ambient air temperature: 20 ° C
   3. iii. Duration: 1 minute
7. 7. Fast cooling of the bottle
   1. i. Cooling by spraying with water at 20 ° C until the packaging is returned to ambient temperature and its contents

Claims (11)

A method of packaging a liquid in a plastic container having a high molecular orientation; process comprising the following steps: filling the container with a high temperature liquid, - closing the container tightly, characterized in that said container is allowed to retract consecutively to said closing step. Process according to the preceding claim wherein the walls of the container are cooled during the filling step. Process according to the preceding claim wherein the walls of the container are cooled during the closing step. A process as claimed in any one of the preceding claims wherein the walls of the vessel are cooled following the retraction step. A process as claimed in any one of the preceding claims in which a portion of the container walls is cooled. A method as claimed in any one of the preceding claims wherein the walls of the container are heated at least partially following the closing step. A process according to any one of the preceding claims wherein a gas, such as nitrogen or carbon dioxide, is added to the vessel subsequent to the filling step and prior to the closing step. Apparatus for carrying out the method according to any one of the preceding claims comprising means for filling a hot container, means for closing said container and means for allowing retraction of said container. Device according to the preceding claim comprising means for cooling the walls of said container. Device according to claim 8 or 9 comprising means for heating the walls of said container. A highly oriented plastic container containing a liquid and obtained according to a method according to any one of claims 1 to 6, characterized in that its volume after conditioning is lower than its initial volume.

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