EP3599092A1 - Method for depositing a functional layer on a container - Google Patents

Abstract

Method for treating a surface of a container, such as a bottle, in the beverage processing industry, wherein a functional layer is applied to a non-oxidized surface of the container in a container treatment machine.

Description

The present invention relates to a method for treating a surface of a container according to claim 1 and a container treatment machine for treating a surface of a container according to claim 9.

State of the art

In the packaging industry, in particular in the beverage processing industry, containers based on plastics, in particular PET and other materials such as glass or metal, are often used. If the outer surface of these containers is to be printed or otherwise processed, it must be ensured that the materials to be applied also adhere to the surface of the container. Since the properties (physical and / or chemical) of the surface of containers are dependent on the material used and are also not homogeneous for a given container, various possibilities have been given in the past for the properties of the surface of the container with regard to wetting with printing inks or other materials.

That's how it beats EP 2 089 234 B1 proposed a method in which a primer and then a printed image are applied to the container using digital techniques. The primer can be prescribed to improve the adhesive properties of the printing ink applied thereon.

However, it turns out to be problematic that the primer also has to adhere to the surface of the container and its composition therefore depends on the container material, which can also influence the adhesive properties of the printing ink applied to the primer.

On the other hand, the EP 1 148 036 B1 proposes to first oxidize the surface of a container with the aid of burners and then to apply an adhesion-promoting functional layer to the oxidized surface by means of flame pyrolysis, silicon-containing materials in particular being used here. Due to the many different process steps that are necessary for pretreating the surface of the container, the pretreatment of the container becomes complex and is also highly dependent on the underlying container material. There is also a risk of charring the container surface with these methods.

Furthermore, methods are now known in which surfaces, in particular plastic surfaces, are treated by means of a pure atmospheric plasma. The plasma emerges from a nozzle as a deformed arc. The spatial expansion of the plasma jet perpendicular to the direction of movement is usually small, so that the surface has to be treated in several sections. Furthermore, it has been problematic with this method that the containers are contoured, that is to say they have a surface shape that deviates from an essentially smooth surface (for example with grooves). Since the plasma beam has only a small depth of field or effective width, it was previously only possible to treat containers with a smooth surface, essentially without contouring.

task

Starting from the known prior art, the technical problem to be solved is therefore to specify a method and a container treatment machine which achieve an improvement in the wettability of the surface of a container, but at the same time make less specific demands with regard to the complexity of the method carried out or the container treatment machine.

solution

This object is achieved according to the invention by the method according to claim 1 and the container treatment machine for treating a surface of a container according to claim 9. Advantageous further developments of the invention are covered in the subclaims.

The method according to the invention for treating a surface of a container, such as a bottle, in the packaging industry comprises that a functional layer is applied to a non-oxidized surface of the container in a container treatment machine.

The functional layer is a layer that is applied to the surface of the container before the container is wetted with a printed image or any printing ink at all. The application of the functional layer does not include any methods that require digital printing of such a functional layer.

The non-oxidized surface of the container is to be understood as that surface which was not treated in a previous process step by an oxidizing flame or other processes which would oxidize the molecular groups on the surface of the container. If the functional layer is applied to such a non-oxidized surface, preceding process steps which already oxidize or otherwise process the surface of the container can be omitted, so that the entire process is less complex, but at the same time due to the formation of the functional layer on the surface Surface of the container good wettability is ensured by printing inks. In particular, it can be achieved that a uniform functional layer is applied to a wide variety of substrates, thus creating a uniform, printable surface for all types of containers (substrates). The development effort for printing inks that can be used on a wide variety of substrates can thus be completely eliminated or at least considerably reduced.

The functional layer can preferably be applied by means of flame pyrolysis, plasma coating or XUV radiation, a preferably gaseous precursor being admixed to the flame / the plasma / in the region of the XUV radiation, which is on and / or with the surface of the container forms the functional layer.

In one embodiment, the container treatment machine comprises a flame pyrolysis device, the non-oxidized surface of the container being flamed in the presence of a precursor and the functional layer being applied to the non-oxidized surface at least in the area which is flamed by the flame pyrolysis device. The flamed area of the surface is the area that is in direct contact with the flame generated by the flame pyrolysis devices.

In this embodiment, the precursor can be introduced as a gas or droplet into the flame or the flame pyrolysis devices itself, so that it also strikes the surface of the container in the area of the flame and forms an adherent functional layer there by chemical reactions on the surface. It goes without saying that the precursor which was originally introduced into the flame no longer has to be chemically identical to the material which forms the "functional layer". In any case, the functional layer is at least partially formed by the precursor.

In a further development of this embodiment, two flame pyrolysis devices are provided and the containers are transported in a transport device which transports the containers past the flame pyrolysis devices in the transport direction, the flame pyrolysis devices being arranged one after the other in the transport direction and the non-oxidized surface of the container flame one after the other, and / or wherein the flame pyrolysis devices are arranged on opposite sides of the transport device and the container Flame at the same time, and / or wherein the flame pyrolysis devices are arranged on the same side of the transport device and simultaneously flame the container, and / or wherein the flame pyrolysis devices are arranged one above the other in a direction perpendicular to the transport direction of the containers and the flame pyrolysis devices from one another Flame different areas of the container at the same time. Since the flame treatment with the precursor does not involve any oxidation processes, this embodiment enables the surface of the container to be flame-coated with the precursor as quickly as possible, while the layer thickness of the functional layer can advantageously be adjusted and increased.

Alternatively, it can be provided that the container treatment machine comprises a plasma nozzle (instead of flame pyrolysis devices), the surface of the container being acted upon by a plasma containing the precursor and the functional layer being applied at least in the area on the non-oxidized surface which the plasma nozzle is exposed to the plasma.

The plasma is preferably a low-temperature plasma. By using plasma at a lower temperature, the functional layer can be applied to the surface of the container in a practically non-destructive manner, as a result of which accidental damage and charring of the surface of the container can be avoided.

In a further development of this embodiment it is provided that the container is moved along its longitudinal axis, while the plasma nozzle acts on the surface of the container with the plasma. Since the area of action of the plasma nozzle is usually small in comparison to the dimensions of the surface of the container, the application of the entire surface of the container can be realized with this embodiment.

It can further be provided that the container is rotated about an axis (in particular its longitudinal axis) while the functional layer is applied to the non-oxidized surface. In this way, the functional layer can also be coated all round.

Furthermore, it can be provided that the movement of the container relative to the plasma nozzle is controlled in such a way that the distance from the plasma nozzle to the surface of the plasma nozzle is always constant or essentially constant. This can include that the container is both moved along an axis (in particular its longitudinal axis) and / or rotates (simultaneously). Furthermore, the container can be moved translationally in a plane perpendicular to the axis, so that, for example, the distance between the axis and the plasma nozzle is changed. This is particularly advantageous for non-round containers (containers with a non-round cross-section) and contoured containers, also to avoid collisions with the plasma nozzle.

The fact that the distance from the surface to the plasma nozzle is only “essentially” constant means that, in particular in the case of embossings or raised text on the surface of the container or elevations / depressions on the surface which have only a small spatial extent, an adaptation of the distance between the surface and containers do not take place if the extent of these elevations / depressions, ebmossings, raised texts in the direction of the plasma nozzle is substantially smaller than the distance of the remaining surface from the plasma nozzle (for example less than 20% or less than 10% or less than 2% than the distance between the rest of the surface and the plasma nozzle).

In one embodiment it is provided that the distance of the non-oxidized surface which is flamed by the flame pyrolysis device or which is charged with plasma by the plasma nozzle to the flame pyrolysis device or to the plasma nozzle remains constant, while the container is relative to the flame pyrolysis Device or is turned to the plasma nozzle. In the case of non-round containers, it can thus be ensured that the functional layer is applied over the entire surface under the same conditions as possible.

The precursor can further comprise at least one of silicon, organometallic compounds, titanium, silicon-containing compounds. These can be reliably applied to the surface of containers and can have a positive influence on their properties with regard to wetting with printing inks.

The container treatment machine according to the invention for treating a surface of a container, such as a bottle, in the packaging industry comprises a transport device for transporting the containers along a transport direction and two flame pyrolysis devices which are arranged and designed, a surface of a container which transports in the transport device is to flame and to apply a functional layer and is characterized in that the flame pyrolysis devices are both arranged on the same side of the transport device.

This special arrangement of the flame pyrolysis devices facilitates access to them and also simplifies the construction of the lines necessary for introducing the precursor into the flames, since these do not have to be led around the entire container treatment machine, but only have to be provided on one side.

In a further development, the flame pyrolysis devices are arranged one after the other in the transport direction and aligned such that a first flame pyrolysis device brings out the flames in a first direction and the second flame pyrolysis device brings out the flames in a second direction.

It goes without saying that the first direction and the second direction must be provided at least in such a way that the flame is brought out in the direction of the transport device in such a way that a container located therein which is transported past the flame pyrolysis devices also through the flames can be flamed. The arrangement of the flame pyrolysis devices in this way can ensure that the entire surface of the container is also subjected to a flame, preferably a homogeneous flame.

In a further development of this embodiment, the first direction and the second direction are parallel to one another. At the same time, this embodiment allows different areas of a container moving past the flame pyrolysis devices to be flame-treated, which can reduce the total time for applying a functional layer with a predetermined thickness.

In a further development it is provided that the first and second flame pyrolysis devices are at different distances from the transport device. This can be particularly advantageous when flaming containers with a non-round cross-section.

In an alternative embodiment it is provided that the first and second directions enclose an angle α with one another, which is given by α = β + γ , where β and γ are the angles enclosed by the first and the second direction with a plane perpendicular to the transport direction , Different requirements with regard to flaming the surface of the container can be realized in this way.

und der Abstand d der ersten und zweiten Flammenpyrolyse-Einrichtung zur Transporteinrichtung und der Abstand e der Flammenpyrolyse-Einrichtungen zueinander stehen in der Beziehung $\frac{e}{2d}\ge \tan \frac{\alpha }{2}\mathrm{.}$

Die Flammenpyrolyse-Einrichtungen sind in dieser Ausführungsform so angeordnet, dass ein Bereich der Oberfläche des mit der Funktions-Schicht zu beaufschlagenden Behälters gleichzeitig von beiden Flammenpyrolyse-Einrichtungen aus unterschiedlichen Richtungen beflammt wird. Dies erhöht die Ausbringrate des Precursors zum Bilden der Funktions-Schicht auf der Oberfläche und kann gleichzeitig sicherstellen, dass auch im Schattenbereich der ersten Flamme liegende Bereiche der Oberfläche durch die zweite Flamme beaufschlagt werden.In a further development of this embodiment $\beta =\gamma =\frac{\alpha }{2}$

and the distance d of the first and second flame pyrolysis devices to the transport device and the distance e of the flame pyrolysis devices are related to one another $\frac{e}{2d}\ge \tan \frac{\alpha }{2}\mathrm{,}$

In this embodiment, the flame pyrolysis devices are arranged such that a region of the surface of the container to be loaded with the functional layer is simultaneously flamed by the two flame pyrolysis devices from different directions. This increases the application rate of the precursor for forming the functional layer on the surface and can simultaneously ensure that regions of the surface lying in the shadow region of the first flame are also acted upon by the second flame.

Furthermore, it can be provided that the transport device comprises a rotating device which is designed to rotate a container transported by the transport device during the exposure to the flame pyrolysis devices in such a way that the distance between the surface exposed to the flame and the flame pyrolysis device is always the same is. This means that the geometric properties when the container is loaded with the functional layer can remain constant even in the case of non-round containers.

Alternatively, a container treatment machine can also be provided, which comprises a transport device for transporting the containers along a transport direction and a plasma nozzle, the plasma nozzle being designed to apply a plasma containing a precursor to a non-oxidized surface of the container in order to form a functional layer to deposit on the surface of the container.

Brief description of the figures

Fig. 1

schematic representation of a container treatment machine according to an embodiment

2a-c

schematic representation of various embodiments with flame pyrolysis devices

Fig. 3

schematic representation of an embodiment with plasma nozzle

Detailed description

Fig. 1 shows a container treatment machine 100 according to the invention in accordance with an embodiment of the type that can be used in the packaging industry, in particular the beverage processing industry. The container handling machine can be designed in various ways. In the embodiment shown here, it is designed as a linearly operating container treatment machine which comprises a transport device 110 which transports containers 130 through the container treatment machine. This can be a conveyor belt or other devices for transporting the containers. Instead of a conveyor belt, a transport device can also be provided which transports the containers in a hanging manner. For example, a transport device can lead through the container treatment machine, which comprises a series of holders, which hold the containers in the area of the support ring usually provided, for example with the aid of clamps. In this case, it can also be advantageously provided that the containers can be rotated by the holders.

Alternatively, a number of turntables can be provided together with centering devices assigned to them, which are guided through the container treatment system. In such a case, an embodiment of the container treatment machine 100 is particularly advantageous, which comprises a carousel as the transport device, on the periphery of which the turntable and centering devices are arranged. Instead of the turntable and centering devices, transport devices are also considered here that transport the containers in a hanging manner.

In any case, according to the invention, a device 101 is provided in the area of the container treatment machine, which can apply a functional layer to the containers 130 so that they are coated. These containers then exit the container treatment machine 100 as containers 131. The containers can be containers. These can consist, for example, of PET or comprise this. Other plastics for containers used in the packaging industry can also be used here. Furthermore, treatment of glass containers or metallic containers according to the invention is also possible.

Optionally, a further container treatment unit 121 can be provided in the container treatment machine, which feeds the containers to a further treatment step (for example the application of printing ink or the like), so that the processed containers 132 are produced from the containers 131 that are initially only provided with the functional layer can then be removed from the container handling machine.

Several additional devices 102 can be assigned to the device 101, for example a control unit or a storage container in which material which is to serve as a precursor is stored in gaseous or liquid form. The device 101 is generally designed in such a way that it can dispense the precursor material and, in addition, the precursor material is deposited in the form of a layer on the surface of the containers 130 and bonds to the surface of the containers by chemical reactions.

Materials which are based on silicon and form a silicon oxide layer on the surface of the containers 130 are particularly preferably used here. Other materials, including organic compounds or organometallic compounds which represent organic compounds with a metallic portion, are also suitable here. Likewise, titanium-based compounds or generally silicon-containing compounds can be provided as precursors.

According to the invention, there is no intentional oxidation of the container material and in particular of the surface to which the precursor is to be applied before the precursor is applied to the surface of the container. In particular, this includes that none Oxidation of the surface of the container upstream of the device 101 takes place with the aid of flame and oxygen.

For this purpose, the parameters under which the precursor is applied to the surface of the container are selected such that the precursor can also form a permanent connection with a surface of the container that is not intentionally oxidized, so that the precursor or the functional layer formed with it form a permanent connection with the surface of the container and can serve as a basis for the application of printing inks or the like.

The amount of oxidizing oxygen and hydroxyl radicals in the flame (or, as described below, the plasma) can be adjusted according to the gas-air ratio selected. Furthermore, when using silicon-based precursors, sufficiently highly reactive, layer-forming silicon species can also arise in the flame (the plasma). By contact with the surface of the container, the top (or the top) molecular layer on the surface of the container forms carbonyl, carboxyl or hydroxyl groups, which bind very well chemically with the silicon species.

The device 101 can be implemented in different ways, but flame pyrolysis devices and plasma nozzles are particularly preferred.

The show 2a-c Embodiments in which the container treatment machine 100 comprises, as a concrete implementation of the device 101, at least two flame pyrolysis devices 251 and 252 arranged on the same side of the transport device 110. The flame pyrolysis devices 251 and 252 are generally arranged such that they can discharge flames 261 and 262 onto a container 130 transported in the transport device 110 along the transport direction 295, so that the surface of the container is flamed, that is to say the flame is applied to it. Contained in this flame or transported with it is the precursor material or the precursor which, in particular due to the high thermal energy in the area of the flames 261 and 262, makes connections to the surface of the container and thus a functional layer on the surface of the Container builds up. The precursor can, for example, the individual flame pyrolysis devices 251 and 252 from the storage container (see reference number 102 in FIG Fig. 1 ) are fed. The precursor material that is fed to the flame pyrolysis device 251 does not have to be identical to the precursor material that is fed to the flame pyrolysis device 252.

In principle, the flame pyrolysis devices 251 and 252 can be arranged at any distance, in particular at any distance from one another. According to the invention, they are only arranged such that they can each flame the surface of the container 130. For this purpose, they are preferably arranged at a distance d from the conveyor belt or from the surface of a container 130 transported therein, which is so large that the flame generated by the respective flame pyrolysis device can flame the surface of the container. Typical distances are in the range of a few cm, up to 15 cm.

The largest possible area of the surface of the container 130 is flamed by the respective flame pyrolysis device. This in turn can reduce the total time required to apply the functional layer to the surface of the container if the container is also rotated about its axis of rotation R (here perpendicular to the image plane) while it is being transported along the transport device. Depending on the layer thickness provided, but also on the transport speed of the containers in the transport device 110, it can either be provided that the containers are not moved in the transport direction 295, but that they are acted upon by the flame pyrolysis devices 251 and 252 or that the movement the container 130 takes place continuously along the transport device 110 in the direction 295 while being rotated, for example, about its own axis.

In the in Fig. 2a In the illustrated embodiment, the flame pyrolysis devices 251 and 252 are beveled with respect to a plane 290 which is perpendicular to the transport direction 295, so that they include the angle β for the flame pyrolysis device 251 and the angle γ for the flame pyrolysis device 252. These angles are measured in the plane shown here, ie in a plane parallel to the transport plane defined by the transport direction 295. When using a conveyor belt for the containers, this transport level corresponds exactly to the level defined by the conveyor belt.

The angles β and γ can be chosen as appropriate. However, it is particularly advantageous if the discharge directions (also called exit directions) of the flames 261 and 262, which are ultimately defined by the angles β and γ , are designed such that both directions cross, as shown in FIG Fig. 2a is shown.

In particular, it can be provided that the angle enclosed by the directions of discharge of the flames 261 and 262 (shown here in dashed lines) results from α = β + γ .

gilt. In einem solchen Fall ist das Verhältnis zwischen dem Abstand e der Austrittsöffnungen in den Flammenpyrolyse-Einrichtungen 251 und 252 zum Abstand d (genauer zur Projektion des Abstands d in die Ebene senkrecht zur Transportrichtung) zwischen Oberfläche des Behälters 130 (bzw. zum Rand der Transporteinrichtung 110) und den Austrittsöffnungen in den Flammenpyrolyse-Einrichtungen 251 und 252 bevorzugt so, dass gilt $\frac{e}{2d}\ge \tan \frac{\alpha }{2}\mathrm{.}$

The intersection of the two directions can be chosen at any point relative to the transport device. However, it is preferred if the point of intersection is not in the area in which the flames also strike the surface of the container. For this purpose, it can be provided in a particularly preferred embodiment that the angles! β and γ are the same size, so in particular $\frac{\alpha }{2}=\beta =\gamma$

applies. In such a case, the ratio between the distance e of the outlet openings in the flame pyrolysis devices 251 and 252 to the distance d (more precisely for projecting the distance d into the plane perpendicular to the transport direction) between the surface of the container 130 (or to the edge of the transport device) 110) and the outlet openings in the flame pyrolysis devices 251 and 252 are preferably such that the following applies $\frac{e}{2d}\ge \tan \frac{\alpha }{2}\mathrm{,}$

This ensures that the intersection of the directions in which the flames emerge from the flame pyrolysis devices 251 and 252 is either at or just behind (in the direction of movement of the flames) the surface of the container 130. This can be particularly advantageous if the flame pyrolysis devices 251 and 252 discharge different materials as precursors, which together form a stable functional layer on the surface of the container. In this case it can be ensured that a possibly desired chemical reaction of these two materials only occurs immediately when it hits the surface of the container and thus takes place in the presence of the container material, which can favor the deposition of the final functional layer.

Fig. 2b shows an alternative embodiment in which the flame pyrolysis devices 251 and 252 are arranged in relation to one another such that the directions of exit of the flames from the flame pyrolysis devices 251 and 252 are parallel to one another, but the flame pyrolysis devices are optionally arranged at a distance L perpendicular to the transport direction are. The flame pyrolysis devices are further arranged one after the other in the transport direction 295. An embodiment is preferred here in which the first flame pyrolysis device 251 in the transport direction is arranged closer to the transport device by the distance L than the flame pyrolysis device 252 following in the transport direction. This embodiment can first intensively flame the surface of the container 130 done by flame 261. Since the statistical distribution of the molecules of the precursor forming the functional layer can be subject to significant fluctuations due to the high concentration in the vicinity of the discharge opening from the flame pyrolysis device 251, there may be deviations in the layer thickness. These can also lead to a layer thickness of the functional layer that is less than a minimum layer thickness.

For this purpose, the flame pyrolysis device 252 following in the transport direction, which is arranged at a greater distance from the surface of the container, can effect a more uniform distribution of precursor material on the surface, so that at least deviations in the layer thickness such that the resulting layer thickness is less than a minimum layer thickness is to be avoided. For this purpose, the flow rate or concentration of precursor material in the second flame 262 can also be controlled such that the layer thickness that forms on the surface of the container alone corresponds to 50% or even 75% of the minimum layer thickness due to the second flame.

The flame pyrolysis devices 251 and 252 can be spaced apart from one another in such a way that they do not simultaneously flame different areas of the surface of the container 130. In particular, the distance between the first flame pyrolysis device 251 and the second flame pyrolysis device 252 can be 15 cm to 30 cm or more, so that first the surface of the container is flamed by the first flame pyrolysis device 251 and then the container is transported further, without flaming. During this time, the surface of the container can be cooled briefly, so that its temperature drops and charring is avoided by applying the second flame pyrolysis device 252.

The embodiment according to the Fig. 2b also allows the use of different precursor materials to form a two-layer system from functional layers in such a way that a first layer consisting of a first precursor material is applied by the first flame pyrolysis device and by the second flame pyrolysis device 252 a second precursor material is applied, which forms a second functional layer over the first functional layer. With this embodiment, a gradient can be formed in the layer structure with respect to certain chemical or physical properties, starting from the surface up to the last functional layer, before a printing layer or the like is applied. This embodiment is not limited to just two functional layers, but can also include the application of several functional layers with different thicknesses and / or in different areas of the surface of the container.

In the in Fig. 2c In addition to the two flame pyrolysis devices 251 and 252, the embodiment shown is provided on one side of the transport device 110 with two further flame pyrolysis devices 271 and 272, which are arranged on the side of the transport device opposite the container. In the in Fig. 2c In the illustrated embodiment, the flame pyrolysis devices 251, 252 and 271 and 272 are as one In principle, the plane defined by the transport direction 295 is mirrored. This means in particular that in the embodiment shown the flame pyrolysis devices 252 and 272 arranged in the transport direction of the container flow are each spaced further apart from the transport device than the flame pyrolysis devices 251 and 271 arranged first in the transport direction.

This is not mandatory. According to the previously described embodiments, the flame pyrolysis devices can also be arranged at the same distance and do not have to be arranged parallel to one another with respect to the direction in which the flames are brought out. The flame pyrolysis devices 251 and 252, and 271 and 272 can also be analogous to Fig. 2a be arranged. The angles which the respective flame pyrolysis devices enclose with one another do not have to be the same, but can differ for the devices 251 and 252 from those of the devices 271 and 272.

It can also be provided that only one further flame pyrolysis device (for example 271) is provided on one side of the transport device, while the flame pyrolysis devices 251 and 252 and optionally further flame pyrolysis devices are arranged on the other side of the transport device. As in Fig. 2c also shown, the flame pyrolysis devices can also be arranged offset to one another in the transport direction. However, embodiments are also conceivable in which the arrangements of the flame pyrolysis devices on one side of the transport device (for example 251 and 252) are only mirrored on the other side of the transport device. All related to Fig. 2c The embodiments described can, depending on their expediency, be used to ensure either faster and more uniform treatment or special treatments. This can be particularly advantageous in the case of containers which are not rotationally symmetrical or which do not have at least one axis of symmetry (containers which are generally not round).

While this is not shown in detail here, several flame pyrolysis devices can also be arranged one above the other (perpendicular to the transport plane of the containers in the transport device). These can either have identical application directions and / or have different application directions. This can be achieved, for example, by tilting the flame pyrolysis devices against one another. In particular, the application directions of flame pyrolysis devices in a first level can differ from those in a second level. This embodiment is with each of the in the 2a to 2c described variants can be combined. In particular, each of the variants in 2a to 2c as Representation of a level of flame pyrolysis devices are to be understood, with further levels of flame pyrolysis devices emerging from the image plane likewise according to embodiments according to 2a to 2c possible are.

In particular, the flame pyrolysis devices arranged in this way in a direction perpendicular to the transport direction can simultaneously flame different areas of the container, in particular areas at different heights (measured with respect to a transport plane in which the containers are transported), in order to separate the functional layer.

Fig. 3 shows a further embodiment in which, instead of the flame pyrolysis devices, a plasma nozzle is used to apply the precursor to a container and to apply a functional layer to the surface of the container.

The plasma nozzle 341, which preferably also includes a dosing device for precursor material for forming the functional layer, is arranged in such a way that it forwards a plasma 342, which at least also includes the precursor material, in a transport device the plasma nozzle 341 can be applied along moving containers.

In this embodiment, the transport device is preferably formed at least by a standing plate 343 on which the container is arranged standing. As already with reference to Fig. 1 described, it can further be provided that each stand plate 343 is assigned a centering device (not shown here), for example in the form of clips, which can grip around the container on the support ring or another area and thus stabilize it.

The plate 343 is particularly preferably designed as a turntable so that it can rotate the container 130 on the plate 343 about the axis of rotation R, which can preferably coincide with the longitudinal axis of the container. Thus, the precursor can be applied to the entire circumference of the container 130 through the plasma nozzle 341.

Since the plasma nozzle 341 is located comparatively close to the surface of the container (a few mm to a few cm), the area on which the plasma 342 can be applied to the container 130 in the longitudinal direction extends only over a small section in the longitudinal direction, which corresponds to the degree of dispersion of the plasma 342 after leaving the plasma nozzle 341. However, since the entire surface of the container with a typical length of at least 7 cm, in particular approximately 10 mm to 200 mm and rarely even more, should be coated with the precursor material in the direction of the axis of rotation, provision can be made be that in addition to the rotation, a translational movement is carried out parallel to the axis of rotation R. This translational movement can either be carried out by the container on the turntable 343 (for example in cooperation with a suitable centering device) or the plasma nozzle 341 can be moved parallel to the axis of rotation. Combinations of these are also conceivable.

In order to ensure that the entire surface of the container has also been exposed to the plasma and a sufficient functional layer is thus formed, a plurality of plasma nozzles 341 can be arranged one after the other in the transport direction, each of these plasma nozzles delivering plasma to the surface of the container in order to function Layer to form.

It can be provided that each of the nozzles only coats plasma with a certain angular range, but for the entire length of the container, or that each of the nozzles applies the functional layer along the entire circumference during a full rotation of the container about its axis of rotation R , however in each case only a certain area in the longitudinal direction (ie parallel to the axis of rotation) with the plasma. It can also be provided that there is an overlap between the areas coated by the individual plasma nozzles, so that at least no area remains on the surface of the container that has not been coated with a plasma.

Alternatively, the plasma can be applied to the surface of the container with an overlap using a plasma nozzle alone. The plasma nozzle can thus apply a plasma to a first region (in the longitudinal direction and / or direction of rotation) and subsequently act on a second region which partially overlaps the first.

Since the containers are usually hardly spaced apart from the plasma nozzle 341 (to a few mm to 1 cm), it can also be provided that the plasma nozzle 341 can be moved in several spatial directions, in particular “back and forth” in the illustrated double arrow direction 344, so that it can be moved toward the container 130 or away from the container 130. Tilting of the plasma nozzle 341 along the double arrow 345 (ie tilting in a plane perpendicular to the direction of transport) can also be provided in order to reliably reach regions of the container that are curved in the longitudinal direction.

Furthermore, a control unit can be provided which controls suitable alignment means for aligning and / or moving the plasma nozzle 341 depending on the shape of the container 130 such that the distance between the plasma nozzle 341 and the surface of the container 130 is constant while the container 130 is rotated about the axis of rotation R relative to the plasma nozzle 341 and / or is moved parallel to the axis of rotation R.

A distance sensor, for example a laser diode or a similar optical sensor, can be provided to determine the distance. It can also be provided that, for example, data about the shape of the container stored in a memory assigned to the container treatment machine can be used to determine the distance between the surface of the container and the plasma nozzle at a specific position of the container. Additionally or alternatively, a 3D scan method can be used to determine the position and / or shape and / or current dimensions of the container and thus the distance to the plasma nozzle either once when the container is taken into the container treatment machine or repeatedly to determine.

The plasma released by the plasma nozzle 341 is particularly preferably a low-temperature plasma.

Furthermore, it can be provided that an area in the container treatment machine in which the container is charged with plasma has a negative pressure, in particular a vacuum with a pressure of less than 10 ^-4 bar. The dispersion of the plasma discharged from the plasma nozzle 341 can thus be reduced.

Furthermore, it can be provided that an electrode is introduced within the container 130 and the plasma nozzle 341 functions as a counterelectrode, so that a potential difference arises between the electrode introduced into the container 130 and the plasma nozzle 341 and the surface of the container is polarized, the polarization thus it is selected that at least the precursors contained in the plasma experience an acceleration in the direction of the surface of the container 130. If the precursors contained in the plasma are negatively charged, for example, the surface of the container and thus the electrode in the container 130 should be positive in order to attract the precursor. Accordingly, the electrode is negatively charged when the precursor in plasma 342 is positively charged.

The plasma nozzles used in the invention can be plasma nozzles that are already commercially available. Since these can be operated in accordance with the method described, no or only slight structural modifications to such plasma nozzles are necessary in order to use them together with the method according to the invention. Regardless of whether flame pyrolysis facilities according to the terms Fig. 2 Embodiments described or plasma nozzles according to the in Fig. 3 Embodiment described, it can be provided that the container in the transport plane perpendicular to the transport direction and perpendicular to an intended rotation axis R can be moved in a direction s, so that the distance from the surface of the container, which is either flamed by the flame pyrolysis device or is charged with plasma from the plasma nozzle, is constant to the flame pyrolysis device or to the plasma nozzle. This is particularly advantageous in the case of non-round containers, since undesired collisions with the flame pyrolysis devices and the plasma nozzles, but also excessive heating, especially when using flame pyrolysis devices, can be prevented.

In order to implement this control, a distance from the container to the flame pyrolysis device or to the plasma nozzle is preferably determined in a starting position. If the containers are clamped by a stand plate and a centering device or held by holders, this determination can be replaced by a value stored in an internal memory of the container treatment machine or a control unit assigned to it. The movement of the container in the direction s is then controlled so that the distance k of the surface of the container to the flame pyrolysis device and / or to the plasma nozzle is constant. Since the distance r of the surface to the axis of rotation R can change with respect to a predetermined s direction when the container is rotated (in the case of containers with a non-round cross section), the control unit will control the transport device so that the position of the container along the direction s is controlled Change in position Δ s = Δ r = r ₀ - r ( ϕ ) is the change in position of the entire container and also of the axis of rotation R with respect to a fixed zero point along the direction s.

Here r _{0 is} an arbitrary reference value. r ₀ can also be zero or set as r ₀ = k . r ( ϕ ) indicates the distance from a point on the surface of the container to the axis of rotation R as a function of the angle of rotation, measured along the connecting line between the axis of rotation and flame pyrolysis device and / or plasma nozzle, of the container.

This movement ensures that a point on the surface which is currently being acted upon by the flame pyrolysis device or the plasma nozzle always has the predetermined distance k from the flame pyrolysis device or from the plasma nozzle.

Claims (16)

Method for treating a surface of a container, such as a bottle, wherein a functional layer is applied to an unoxidized surface of the container in a container treatment machine (100). The method of claim 1, wherein the container treatment machine (100) comprises a flame pyrolysis device (251, 252), the non-oxidized surface of the container being flamed by the flame pyrolysis device in the presence of the precursor and the functional layer at least in the area the non-oxidized surface is applied, which is flamed by the flame pyrolysis device. The method of claim 2, wherein the container treatment machine (100) comprises two flame pyrolysis devices (251, 252), and the containers are transported in a transport device (110) which transports the containers past the flame pyrolysis devices in the transport direction,
wherein the flame pyrolysis devices (251, 252) are arranged one after the other in the direction of transport and flame the unoxidized surface of the container one after the other; and or
wherein the flame pyrolysis devices (251, 252) are arranged on opposite sides of the transport device (110) and simultaneously flame the container; and or
wherein the flame pyrolysis devices (251, 252) are arranged on the same side of the transport device (110) and simultaneously flame the container;
and or
wherein the flame pyrolysis devices are arranged one above the other in a direction perpendicular to the direction of transport of the containers and the flame pyrolysis devices simultaneously flame different areas of the container. The method of claim 1, wherein the container treatment machine (100) comprises a plasma nozzle (341), wherein the surface of the container is acted upon by a plasma (342) containing the precursor and the functional layer is used up at least in the area on the non-oxidized surface which is admitted by the plasma nozzle with the plasma. The method of claim 4, wherein the container is moved along its longitudinal axis while the plasma nozzle (341) applies the plasma to the surface of the container. Method according to one of claims 1 to 5, wherein the container is rotated about an axis while the functional layer is applied to the non-oxidized surface. Method according to one of claims 2 to 6, wherein the distance of the non-oxidized surface which is flamed by the flame pyrolysis device (251, 252) or which is charged with plasma by the plasma nozzle (341) to the flame pyrolysis device (251, 252) or the plasma nozzle remains constant while the container is rotated relative to the flame pyrolysis device (251, 252) or to the plasma nozzle. Method according to one of claims 1 to 7, wherein the precursor comprises at least one of silicon, organometallic compounds, titanium, silicon-containing compounds. A container treatment machine (100) for treating a surface of a container, such as a bottle, in the beverage processing industry, the container treatment machine comprising a transport device (110) for transporting the containers along a transport direction and two flame pyrolysis devices (251, 252), which are arranged and formed are to flame a surface of a container which is transported in the transport device (110) and to apply a functional layer, characterized in that the flame pyrolysis devices (251, 252) are both arranged on the same side of the transport device. A container treatment machine according to claim 9, wherein the flame pyrolysis devices (251, 252) are arranged one after the other in the transport direction and are oriented such that a first flame pyrolysis device discharges the flame in a first direction and a second flame pyrolysis device the flame in a second direction comprises applying. The container handling machine according to claim 10, wherein the first direction and the second direction are parallel to each other. A container handling machine according to claim 11, wherein the first and second flame pyrolysis devices are at different distances from the transport device. A container handling machine according to claim 10, wherein the first and second directions form an angle α with one another which is given by 2 α = β + γ , where β and γ are the angles enclosed by the first and the second direction with a plane perpendicular to the transport direction. A container handling machine according to claim 12, wherein β = γ = α and the distance d of the first and second flame pyrolysis devices to the transport device and the distance e of the flame pyrolysis devices in relation to each other $\frac{e}{2d}\ge \tan \frac{\alpha }{2}$

stand. Container treatment machine according to one of claims 9 to 14, wherein the transport device comprises a rotating device which is designed to rotate a container transported by the transport device during the exposure to the flame pyrolysis devices such that the distance of the surface exposed to the flame to the flame pyrolysis -Facilities is always the same. A container treatment machine (100) for treating a surface of a container, such as a bottle, in the beverage processing industry, the container treatment machine comprising a transport device (110) for transporting the containers along a transport direction and a plasma nozzle (341), the plasma nozzle being configured, one not to apply a precursor-containing plasma (342) to the oxidized surface of the container in order to deposit a functional layer on the surface of the container.

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