EP4689223A1

EP4689223A1 - Material processing machine, method for producing a multi-layered material and multi-layered material

Info

Publication number: EP4689223A1
Application number: EP24716776.0A
Authority: EP
Inventors: Stephen Carey; Nicholas Copeland
Original assignee: Bobst Manchester Ltd
Current assignee: Bobst Manchester Ltd
Priority date: 2023-04-03
Filing date: 2024-04-03
Publication date: 2026-02-11
Also published as: CN121127623A; WO2024208885A1

Abstract

A sheet material processing machine (10) for producing a multi-layered material (26) comprises a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminium oxide. The sheet material processing machine (10) comprises a first coating unit (14) for applying the coating layer components comprising silicon oxide on the substrate (22) and a second coating unit (16) for applying the coating layer components comprising aluminium oxide on the substrate, wherein the first coating unit (14) and the second coating unit (16) are arranged along a handling path of the substrate (22).

Description

Material processing machine, method for producing a multi-layered material and multi-layered material

The invention relates to a material processing machine for producing a multilayered material, a method for producing a multi-layered material and a multi-layered material.

Multi-layered materials are used in the packaging industry, especially for packaging products like foodstuff, medical articles pharmaceutical products, industrial products and personal care products. In these applications, typically at least one of the layers of the multi-layered materials is used as a so-called “barrier layer” protecting the packaged good from ambient moisture, ambient air and/or non-ambient gases (e.g. in modified atmosphere packaging (MAP) applications). Generally termed, the barrier layer is used to prevent gas and vapour exchange through the multi-layered material. Further it may also serve as aroma barrier, flavour barrier and/or light barrier.

Known multi-layered materials comprise a substrate made e.g. from a synthetic polymer onto which the barrier layer is applied. As barrier layer, a thin metal layer of aluminium can be used. However, efforts are being made to avoid metallized packaging material to change the recyclability and to reduce the ecological footprint of the material and/or the package made from the material.

At the same time, there is a demand to provide optically transparent packing materials which still provide a barrier layer of high quality.

In this respect, for example barrier layers comprising silicon oxide or aluminum oxide are known. The application can be made by chemical vapor deposition (CVD) or physical vapour deposition (PVD) processes, especially plasma enhanced chemical vapor deposition (PECVD). In PECVD, reactive chemical species are dosed in a chamber and are ionized or electronically excited in a plasma discharge to create free electrons or excited species. Of special interest are transparent layers of silicon oxide prepared by capacitively coupled PECVD (CC-PECVD) which show unique thin film properties not achievable by alternative CVD processes. Other alternatives are for example magnetically enhanced or inductively coupled processes. These unique thin film properties are e.g. high barrier performance, mechanical flexibility and wet adhesion properties suitable for high demanding thermal processing including high temperature and/or high pressure retort applications.

However, the dynamic deposition rate of silicon oxide layers applied by large scale industrial CO- PECVD methods is limited to values of 100 to 150 m/min or less when applying layer thicknesses suitable for food packaging barrier applications even on processing machines with several drum coaters. Thus, for increasing the deposition rate, additional process steps or processing modules must be installed, rendering the overall process uneconomical and increasing the total space or footprint required by the sheet processing machine.

From US 2018/170 017 A1 , a flexible multilayer packaging film is known having one or more barrier layers, each of which comprise an organic layer and an inorganic layer being aluminium oxide or silicon oxide. The inorganic layer is applied by electron beam physical vacuum deposition. However, silicon oxide layers applied by electron beam physical vacuum deposition do not show the unique thin film properties of silicon oxide layers being applied by CC-PECVD or at least only to a reduced extent. In addition, electron beam physical vacuum deposition results in high thermal stress on the substrate to be coated on, rendering the process ineligible for thermal-sensitive substrates. Further, machines for electron beam vacuum deposition have a considerably higher investment cost in comparison to a processing machine relying on PECVD.

In view of the above, it is an object of the invention to provide a cost-effective material processing machine providing a barrier layer with excellent thin-film properties while achieving high deposition rates. A further object of the invention is to provide a cost-effective multi-layered material with good water retention and gas barrier properties and a method for preparing such a material. The object of the invention is solved by a material processing machine for producing a multi-layered material comprising a substrate and a hybrid coating layer applied on the substrate, wherein the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminium oxide and aluminium. The material processing machine comprises a first coating unit for applying the coating layer components comprising silicon oxide on the substrate and a second coating unit for applying the coating layer components comprising aluminium oxide on the substrate, wherein the first coating unit and the second coating unit are arranged along a handling path of the substrate.

Further, the first coating unit comprise at least one first sub-unit for capacitively coupled PECVD and at least one second sub-unit for inductively coupled PECVD. Accordingly, the first sub-unit and the second sub-unit can be used for producing the respective kind of silicon oxide coating at the technology specific deposition rate.

Preferably, all of the first sub-units and of the second sub-units are associated to the same drum of the first coating unit for moving the substrate along the handling path, i.e. a single drum is used in the first coating unit. Thus, the overall cost and space requirement of the first coating unit can be minimized.

The total number of first sub-units and second sub-units will be dependent on the specific design of the first coating unit. E.g., the total number of first sub-units and second sub-units can be in the range of from 2 to 8.

In one variant, the first sub-unit(s) and the second sub-unit(s) are arranged in an alternating manner along the handling path of the substrate. Such an arrangement allows for an especially uniform distribution of coating layer components when both the first sub-unit(s) and the second sub-unit(s) are being used for preparing the hybrid coating layer.

The respective sub-units can be arranged as a module with two or more subunits of the same type. E.g., two first sub-units can form a first sub-unit module and two second sub-units can form a second sub-unit module. In this case, the expression “arranged in an alternating manner” means that the respective modules are arranged in an alternating manner.

Here, the term “capacitively coupled PECVD” means capacitively coupled plasma enhanced chemical vapor deposition, also termed “CC-PECVD”, and the term “inductively coupled PECVD” means inductively coupled plasma enhanced chemical vapor deposition, also termed “IC-PECVD”.

CC-PECVD and IC-PECVD differ in the mode the plasma for the chemical vapor deposition process is generated, the density of the generated plasma and the resulting thin film properties of layers applied by the respective CVD process. In EP0299754A2 a method of plasma enhanced silicon oxide deposition is described. Thus, while this so-called CC-PECVD provides silicon oxide films with best performance characteristics but at low deposition rates, IC-PECVD provides greater plasma density, where plasma density is the number of charged species per unit volume, via higher levels of ionization which enables higher deposition rates than CC-PECVD but with performance characteristics which are below the extent achievable in silicon oxide films applied by CC-PECVD.

Generally, during IC-PECVD, the plasma is sustained by an inductive coupling of power from a power source like an antenna to the plasma.

In contrast, during CC-PECVD, the capacitive plasma is sustained by a voltage difference between the alternating or direct current power source and a counterelectrode.

The generated plasma can be magnetically confined with permanent or electromagnets.

The terms “silicon oxide” and “aluminium oxide” refer to oxides of silicon and aluminium which can also be denoted as “SiO_x” and “AIO_X”, respectively.

The term “aluminium oxide” refers to oxides of aluminium which can also be denoted as “AIOx”; especially aluminium oxide is AIOx with 0.1 < x < 1.5.

The term “silicon oxide” refer to oxides of silicon, which can also be denoted as “SiOx”; especially, the silicon oxide is SiOx with 1 < x < 4 and could further contain other additive elements such as, but not limited to carbon, hydrogen and/or nitrogen. The “silicon oxide” which is deposited is not necessarily purely silicon and oxygen. The SiOx used according to the invention may be an amorphous mixture of silicon, oxygen, carbon, and hydrogen (and perhaps others).

In fact, nitrogen or the creation of more carbon rich silicon oxide could improve the performance of the SiOx.

Especially, the silicon oxide is SiO_x with 1 < x < 2 and/or the aluminium oxide is AIOx with 0.1 < x < 1.5.

The invention is based on the idea to provide a combination of different application methods in a single sheet processing machine which result in a hybrid coating layer combining at least two components, wherein at least one of the components is mainly responsible for providing a high deposition rate, thereby minimizing the overall cost of the sheet processing machine and its use, and at least one of the components is mainly responsible for providing the desired performance and properties of the hybrid coating layer.

E.g., the material processing machine can be used to produce a hybrid coating layer comprising a silicon oxide applied by CC-PECVD for giving the hybrid coating layer the desired thin film properties like a high barrier performance and high mechanical flexibility and aluminium oxide applied by a physical vapor deposition (PVD) process like reactive PVD for increasing the overall deposition rate of the hybrid coating layer to the desired value. Aluminium oxide applied by reactive PVD can be applied at a processing speed of 600 m/min or more resulting in a dynamic deposition rate of up to 40,000 nm m/min, i.e. at a deposition rate being multiple times that of silicon oxide being applied by CC-PECVD which typically is in the range of from 1000 to 1500 nor m/min.

In this way, the substrate, being moved through the first coating unit and the second coating unit along the same handling path, can be easily provided with the desired hybrid coating layer at minimized overall cost.

Compared to known material processing machines, the inventive material processing machine requires less space and less coating units while achieving the same or better target deposition rate and performance level of the produced multilayered material. Alternatively, a higher output and an improvement can be achieved at the same space and cost requirements. Generally, aluminum oxide can be applied by any suitable process. E.g., aluminum oxide can be applied by resistivity heated reactive PVD, electron beam PVD or atomic layer deposition (ALD).

Aluminum can be applied e.g. by resistivity heated PVD.

In one variant, the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminum oxide.

In another variant, the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminum.

The hybrid coating layer can consist of coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminium oxide, especially from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and aluminium oxide applied by resistivity heated reactive PVD.

The sequence in which the first coating unit and the second coating unit are arranged along the handling path is not especially restricted and depends on the desired layer structure of the multi-layered material being produced by the material processing machine. Thus, the first coating unit can be arranged before or after the second coating unit along the handling path.

The first coating unit and/or the second coating unit can comprise a drum for moving the substrate along the handling path, the drum being cooled. In this way, the substrate onto which the hybrid coating layer is applied experiences a reduced amount of thermal stress. Thus, even thermal-sensitive substrate materials can be processed in the material processing machine according to the invention.

Alternatively, the first coating unit and/or the second coating unit can be adapted to guide the substrate along the handling path in a free span manner. In such a design of the first coating unit and/or the second coating unit, the substrate is held in an unsupported arrangement between supporting rollers while the respective layer of material is deposited on the substrate. Material processing machines using a free-span arrangement are described e.g. in WO 2022/090337 A1.

In another variant, the first coating unit comprises at least two first sub-units and at least two second sub-units, the first sub-units all being arranged in a first path section of the handling path and the second sub-units all being arranged in a second path section of the handling path, the second path section following the first path section along the handling path of the substrate. In this variant, the complexity in arranging the first sub-units and the second sub-units can be reduced. Especially, interferences between the first sub-units and the second sub-units when both are being used in the same hybrid coating layer application process can be avoided or at least minimized.

Of course, it is also possible that the at least two second sub-units are arranged in the first path section of the handling path and the at least two first sub-units are arranged in the second path section of the handling path.

The object of the invention if further solved by a material processing machine for producing a multi-layered material comprising a substrate and a hybrid coating layer applied on the substrate, wherein the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the material processing machine comprising a first coating unit for applying the coating layer components comprising silicon oxide on the substrate and a second coating unit for applying the coating layer components comprising aluminum oxide on the substrate, wherein the first coating unit and the second coating unit are arranged along a handling path of the substrate, wherein the silicon-providing first coating unit is arranged upstream of the aluminium- providing second coating unit.

The object of the invention is further solved by a method for producing a multi-layered material comprising a substrate and a hybrid coating layer applied on the substrate, wherein the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD and, aluminum and aluminium oxide, the method comprising the following steps: Providing a material processing machine as described before and moving the substrate at a predetermined processing speed along the handling path, thereby applying the hybrid coating layer on the substrate.

The method according to the invention allows to achieve much higher processing speeds while producing a coating layer (i.e., the hybrid coating layer) with excellent mechanical flexibility, high water retention and gas barrier properties and being better recyclable compared with a barrier coating solely produced by CC-PECVD.

Preferably, the predetermined speed for the first coating unit and the second coating unit is the same.

The predetermined processing speed especially is 225 m/min or more, preferably 300 m/min or more. Thus, the predetermined processing speed is especially larger than twice the processing speed of conventional CC-PECVD processes which are typically limited to a processing speed of 75 to 100 m/min at useful layer thicknesses, especially a layer thickness providing a barrier performance typically used in the food packaging industry.

The maximum predetermined processing speed of the method according to the invention is only limited by i) the maximum processing speed of the coating layer component having the highest processing speed and being used in the hybrid coating layer and ii) the minimum amount of the coating layer component used in the hybrid coating layer having the lowest processing speed, wherein the minimum amount is defined as the amount of the respective coating layer component necessary for obtaining the desired properties of the hybrid coating layer.

According to another object of the invention, the material processing machine for producing a multi-layered material comprising a substrate and a hybrid coating layer applied on the substrate, wherein the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the material processing machine comprising a first coating unit for applying the coating layer components comprising silicon oxide on the substrate and a second coating unit for applying the coating layer components comprising aluminum oxide on the substrate, wherein the first coating unit and the second coating unit (16) are arranged along a handling path of the substrate, wherein the hybrid coating layer is applied on the substrate with a deposition rate of 20 nm/s or more, preferably of 35 nm/s or more.

The deposition rate of the hybrid coating layer denotes the total amount of the hybrid coating layer being applied on the substrate, i.e. denotes an average value of the deposition rates of the coating layer components forming the hybrid coating layer.

The object of the invention is also solved by a multi-layered material comprising a substrate and a hybrid coating layer applied on the substrate, wherein the hybrid coating layer comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminium oxide.

The multi-layered material is preferably a multi-layered packaging material, for example for storing foodstuff, medical products, pharmaceutical products, industrial products or cosmetic products.

The multi-layered material is preferably obtained by the method as described before.

In one variant, the hybrid coating layer has a thickness in the range of 1 to 30 nm, preferably of 5 to 20 nm, particularly preferably of 8 to 15 nm. Hybrid coating layers with a thickness of more than 20 nm can result in an excessive material consumption without substantially improving the properties of the hybrid coating layer.

Preferably, the multi-layered material has a water vapour permeability of less than 2.0 g/(m² x 24 h), at 90 % relative humidity and 37.8 °C.

Water vapour permeability can be measured as WVTR (Water Vapour Transmission R) according to the ASTM F 1249standard or according to ISO 15106-3. The multi-layered material to be measured is clamped in a fixture so that the multi-layered material divides the fixture into a measurement chamber and a test chamber. The multi-layered material is clamped with the substrate facing the test chamber. For a WVTR measurement, a defined test gas is introduced into the test chamber. The test gas has a predetermined humidity, temperature and oxygen content. The measuring chamber contains various sensors that measure the composition of the atmosphere in the measuring chamber.

Also preferably, the multi-layered material has an oxygen permeability of less than 2.0 cm³/(m² x 24 h) at 50 % relative humidity, 23.0 °C and 1 bar.

Oxygen permeability can be measured as OTR (Oxygen Transmission Rate) according to the ASTM F 1972 standard. Similar to the WVTR measurement, the side of the substrate is turned towards the test gas.

The substrate can be a continuous web or a discrete sheet.

The substrate can comprise or consist of a polymer, which especially is selected from the group of polyolefins, polyethylene terephthalate (PET), polylactic acid (PLA), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (PHB), cellophane, polyvinyl alcohol (PVOH) and ethylene vinyl alcohol (EVOH).

Preferably, the substrate comprises a polyolefin, preferably polypropylene and/or polyethylene. E.g., the substrate can comprise or consist of CPP (cast polypropylene), OPP (oriented polypropylene) or BOPP (biaxially oriented polypropylene). Polyolefines can be easily recycled, therefore providing the overall multi-layer material comprising the substrate and the hybrid coating layer with excellent retortability.

In another variant, the substrate comprises a cellulose-based material, e.g. paper.

For reducing the ecological footprint of the multi-layered material, the substrate can comprise or consist of a material being obtainable from a renewable resource. E.g., the material can be polylactic acid (PLA), polyhydroxyalkanoate (PHA), poly- 3-hydroxybutyrate (PHB), cellophane and/or polyvinyl alcohol (PVOH).

In addition to the hybrid coating layer, the substrate can have additional coating layers, either on the same side of the substrate the hybrid coating layer is applied on or on other sides of the substrate. E.g., the substrate can have an additional primer coating or a co-extruded skin-layer for tailoring the overall property profile of the multi-layered material. Further features and advantages of the present invention will become apparent by the following detailed description of preferred embodiments, which are not to be understood in a limiting sense, and the drawings. In the drawings,

- Fig. 1 schematically shows a material processing machine according to the invention with a first coating unit according a first embodiment,

- Fig. 2 shows a second embodiment of the first coating unit of Fig. 1 ,

- Fig. 3 shows a third embodiment of the first coating unit of Fig. 1 ,

- Figs. 4 and 5 show a fourth embodiment of the first coating unit of Fig. 1 ,

- Fig. 6 shows the first coating unit of Fig. 4 in more detail, and

- Fig. 7 schematically shows a multi-layered material according to the invention which can be obtained by the material processing machine of Fig. 1.

Fig. 1 schematically shows a material processing machine 10 according to the invention.

Whereas the Fig. 1 shows a stacked arrangement it could also be beneficial to have the material processing machine according to the invention arranged linearly according to another preferred embodiment.

The material processing machine 10 according to the example comprises a provision unit 12, a first coating unit 14 and a second coating unit 16 which are enclosed by a housing 18 of the material processing machine 10.

The provision unit 12 can be accessed by an operator of the material processing machine 10 for placing an unwinding roll 20 in the provision unit 12, the unwinding roll 20 comprising a substrate 22 rolled on an unwinding reel 24.

Within the material processing machine 10, the substrate 22 is unwound from the unwinding reel 24 and moved along a handling path from the provision unit 12 to the first coating unit 14, to the second coating unit 16 and back to the provision unit 12, in which the processed substrate, now being a multi-layered material 26, is wound on a rewinding reel 28 for obtaining a rewinding roll 30. Termed differently, the material processing machine 10 shown in Fig. 1 is a roll-to-roll processing machine. The substrate 22 can be a continuous sheet having an overall length of e.g. 100 km.

The rewinding roll 30 can be removed by the operator of the material processing machine 10 from the provision unit 12 or by a reel changing mechanism, which can be an automatic reel changing mechanism. The direction of the handling path is indicated in Fig. 1 by arrows. Overall, in the shown embodiment, the material processing machine 10 operates “from roll to roll”.

In the shown embodiment, the unwinding roll 20 and the rewinding roll 30 are arranged geodetically above the first coating unit 14 and the second coating unit 16. Of course, the arrangement of the unwinding roll 20 and the rewinding roll 30 can be different. E.g., the unwinding roll 20 and/or the rewinding roll 30 can be arranged on ground level, i.e. essentially on the same level as the first coating 14 and the second coating unit 16.

Movement of the substrate 22 along the handling path is realized and guided by a multitude of guide rollers 32 which are also responsible for obtaining a desired web tension of the flexible substrate 22 during processing. Though in Fig. 1 all guide rollers 32 throughout the material processing machine 10 are depicted to have the same size and shape, it should be clear that at least some of the guide rollers 32 can be of different size and/or shape than others. Of course, the number of guide rollers 32 can differ from the one shown in Fig. 1.

In addition to the guide rollers 32, the substrate 22 is moved and supported along the handling path by drums 34 and 36, wherein both the first coating unit 14 and the second coating unit 16 each comprise a single drum 34 and 36, respectively. Drums 34 and 36 are cooled such that the substrate 22 is cooled when the substrate 22 is in contact with or arranged in the vicinity of the drums 34 and 36, thereby reducing the thermal stress on the substrate 22 within the first coating unit 14 and the second coating unit 16.

The diameter of the drums 34 and 36 can be chosen according to the space requirements for the respective coating techniques. E.g., drums 34 and/or 36 can have a diameter in the range of 400 to 1000 mm. The first coating unit 14 and the second coating unit 16 are used to apply a hybrid coating layer 38 onto the substrate 22, thereby forming a multi-layered material 26 (see Fig. 7).

The hybrid coating layer 38 comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide.

The first coating unit 14 is adapted to provide all coating layer components based on silicon oxide, while the second coating unit 16 is adapted to provide aluminum or aluminum oxide as coating layer component.

The sequence could also be inversed, e.g. a first coating unit adapted to provide aluminum or aluminum oxide as coating layer component, while a second coating unit is adapted to provide all coating layer components based on silicon oxide.

More specifically, the first coating unit 14 comprises a first vacuum chamber 42 enclosed by a first vacuum chamber housing 44. Thus, the total volume in which the vacuum needs to be created is limited to the total air volume within the first vacuum chamber housing 44.

Within the first vacuum chamber 42, the first coating unit 14 has first sub-units 46 for capacitively coupled PECVD (CC-PECVD) and second sub-units 48 for inductively coupled PECVD (IC-PECVD). Thus, the first subunits 46 are used for applying silicon oxide on the substrate 22 by CC-PECVD while the second sub-units 48 are used for applying silicon oxide on the substrate 22 by IC-PECVD.

It is also possible that the first vacuum chamber, the first coating unit has units for capacitively coupled PECVD (CC-PECVD) or for inductively coupled PECVD (IC-PECVD).

According to the example, the first sub-units 46 and the second sub-units 48 are arranged along the handling path of the substrate 22 in an alternating manner such that each of the first sub-units 46 is followed by a second sub-unit 46 and vice versa. Accordingly, within the first coating unit 14, silicon oxide can be applied on the substrate 22 by CC- PECVD, by IC-PECVD or both before the substrate 22 is being passed on to the second coating unit 16.

Each of the first sub-units 46 and of the second sub-units 48 comprises an antenna 50 which is facing the drum 34. During operation of the first coating unit 14, a plasma is generated between the antennas 50 and the drum 34, when the respective first sub-unit 46 and second sub-unit 48 is used for applying silicon oxide on the substrate 22, while a reactive gas, especially hexamethyldisiloxane (HMDSO) and oxygen, and optionally further process gases like helium are dosed by a dosage system 51 (see Fig. 6), thereby supplying these gases into the first vacuum chamber 42.

For generating the plasma for CC-PECVD, the drum 34 is sustained with a potential difference above a counter electrode, not shown, e.g. a 40 kilohertz voltage. IC-PECVD uses the antenna (50) as plasma source. Of course, being within one vacuum chamber the CC-PECVD and IC-PECVD plasma are expected to interact. For instance, the potential difference between the drum (34) and counter electrode could impart a bias voltage to the IC-PECVD plasma. It is understood, this voltage would increase the energy of ion bombardment at the deposition surface which could be beneficial to performance of the deposited multimaterial layer. The bias voltage can be adjusted as long as a stable plasma for all desired application methods used in a given production run can be generated.

The combination of first sub-units 46 for CC-PECVD and second sub-units 48 for IC-PECVD allows to easily choose between and combine the different methods for producing silicon oxide components of the hybrid coating layer 38.

In Fig. 1 , a total of eight first sub-units 46 and second sub-units 48 are used, wherein each of the sub-units 46 and 48 are present in the same number. Of course, the total number and or the distribution of first sub-units 46 and second sub-units 46 can differ from the embodiment shown in Fig. 1.

The second coating unit 16 is adapted to apply an aluminum species, i.e. aluminum or aluminum oxide on the substrate 22. More specifically, aluminum or aluminum oxide can be applied by the second coating unit 16 on the substrate 22 on which already at least one type of silicon oxide has been deposited before in the first coating unit 14.

Within the second coating unit 16, a second vacuum chamber 52 is formed within a second vacuum chamber housing 54. Thus, the total volume in which the vacuum needs to be created in the second coating unit 16 is limited to the total air volume within the second vacuum chamber housing 54.

Within the second vacuum chamber 52, a physical vapor deposition (PVD) unit 56 is arranged. The PVD unit 56 comprises a heating element 58, e.g. a resistive heating element, which is adapted to heat an aluminium bath 60 for vaporizing aluminium.

Further, during operation of the second coating unit 16, a gas mixture comprising an oxygen species is supplied by a (not shown) dosage system in the second vacuum chamber 52 such that the second coating unit 16 can deposit aluminium oxide on the substrate 22. Thus, the second coating unit 16 is a unit for reactive PVD.

If aluminium is to be supplied on the substrate 22 within the second coating unit 16, the same set-up can be used but without supplying the oxygen species in the second vacuum chamber 52.

Due to the combination of the first coating unit 14 and the second coating unit 16, the shown material processing machine 10 can be used for creating hybrid coating layers 38 with different compositions, thereby producing tailored multilayered materials 26.

E.g., in the first coating unit 14, silicon oxide can be applied only by CC-PECVD, i.e. by the first sub-units 46, and in the second coating unit 16 aluminum oxide is supplied as additional coating layer component of the hybrid coating layer 38. In this way, the resulting multi-layered material 26 collected on the rewind roll 30 has a very good property profile due to the silicon oxide applied by CC-PECVD while the overall deposition rate of the hybrid coating layer 38 can be high enough due to the application of aluminum oxide in the second coating unit 16.

Alternatively, in the first coating unit 14, silicon oxide can be applied only by IC-PECVD, i.e. by the first sub-units 46, and in the second coating unit 16 aluminum oxide is supplied as additional coating layer component of the hybrid coating layer 38.

It is also possible to apply silicon oxide by both CC-PECVD and IC-PECVD, with or without the additional application of aluminum oxide in the second coating unit 16.

Thus, the material processing machine 10 according to the invention provides for a highly flexible and cost-efficient production of multi-layered materials while having an overall compact size.

Of course, the material processing machine 10 can include further processing modules, e.g. an extrusion module for applying a further coating layer on the hybrid coating layer 38 and/or a printing module for applying ink on the substrate 22 or the multi-layered material 26.

In the embodiment shown in Fig. 1 , both the first coating unit 14 and the second coating unit 16 comprise a drum 34 and 36, respectively, on which the substrate 22 is supported when being moved along the handling path. However, it is also possible that the first coating unit 14 and/or the second coating unit 16 is adapted to guide the substrate 22 along the handling path in a free span manner.

In the following, further embodiments of the material processing machine 10 with different first coating units 14 will be described. The further embodiments essentially correspond to the first embodiment such that only differences will be described. Same reference numerals denote same or functionally same components, and we refer to the explanations given above.

Fig. 2 shows selected parts of a second embodiment of the sheet processing machine 10 in which the first sub-units 46 and second sub-units 48 are arranged differently than in the first embodiment.

More specifically, the first sub-units 46 are arranged as first modules 62 each of which comprise two first sub-units 46 arranged next to each other along the handling path of the substrate 22 and the second sub-units 48 are arranged as second modules 64 each of which comprise two second sub-units 48 arranged next to each other along the handling path of the substrate 22. The first modules 62 and second modules 64 are again arranged in an alternating manner along the handling path of the substrate 22.

The arrangement in modules allows to reduce the extent of interferences between the different types of sub-units 46 and 48 used in the first coating unit 14, especially interferences between the plasmas created between the sub-units 46 and 48 and the drum 34. Also, it is possible to design an essentially curved arrangement of the sub-modules 62 and 64, respectively, while still using essentially rectangular-profile antennas 50 such that the arrangement of the antenna 50 more closely follows the circumference of the drum 34.

Fig. 3 shows selected parts of a third embodiment of the sheet processing machine 10 in which the first sub-units 46 and second sub-units 48 are arranged differently compared to the first and second embodiments.

In the third embodiment, all of the first sub-units 46 are arranged in a first half of the circumference of the drum 34, i.e. in the first half of the section of the handling path defined by the drum 34. In the second half of the circumference of the drum 34, all of the second sub-units 48 are arranged.

This arrangement further simplifies the design of the first sub-units 46 and second sub-units 48 and further minimizes the interferences between CC-PECVD done by the first sub-units 46 and IC-PECVD done by the second sub-units 48.

Figs. 4 and 5 show selected parts of a fourth embodiment of the sheet processing machine 10.

In the fourth embodiment, the drum 34 of the first coating unit 14 is interchangeable such that the drum 34 and the first sub-units 46 and 48 associated to the drum 34 can be changed between production runs of the material processing machine 10.

E.g., as shown in Figs. 4 and 5, in a first operation mode of the material processing machine 10, all sub-units associated with the used drum 34 of the first coating unit 14 are first sub-units 46 for applying silicon oxide by CC-PECVD (Fig. 4) and in a second operation mode of the material processing machine 10, all sub-units associated with the used drum 34 of the first coating unit 14 are second sub-units 48 for applying silicon oxide by IC-PECVD. In this way, the overall deposition rate of the individual coating layer component being applicable by the presently used kind of sub-unit can be increased without any further modifications to the other components of the sheet processing machine 10. Further, there cannot be any interference between different kinds of sub-units, simplifying the design of the respective first coating unit 14.

Exchange of the drums 34 and the associated sub-units can be done by a handling system, wherein the drum 34 can be handled e.g. by means of a drum reel 66.

Fig. 6 shows selected parts of the first coating unit 14 of Fig. 4 in more detail.

From this depiction, it can be seen that the first sub-units 46 are mounted on a rack element 68. The rack element 68 provides fixed mounting points for the respective first sub-units 46.

Preferably, the size of the first sub-units 46 and second sub-units 48 are such that they can be mounted on the same rack element 68, i.e. they are of standardized size. Thus, it is possible to easily exchange individual or all of the current sub-units used in the first coating unit 14.

Reactive chemical species can be supplied in the area between the antennas 50 and the drum 34 by means of dosage systems 51. The reactive chemical species can be e.g. hexamethyldisiloxane (HDMSO) and oxygen. Further process gases like helium can be applied by the dosage systems 51 , too.

Overall, the material processing machine 10 according to the invention provides for a highly flexible production of multi-layered materials having an optimized property and cost profile.

Claims

1. Material processing machine (10) for producing a multi-layered material (26) comprising a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the material processing machine (10) comprising a first coating unit (14) for applying the coating layer components comprising silicon oxide on the substrate (22) and a second coating unit (16) for applying the coating layer components comprising aluminium oxide on the substrate, wherein the first coating unit (14) and the second coating unit (16) are arranged along a handling path of the substrate (22), wherein the first coating unit (14) comprising at least one first sub-unit (46) for capacitively coupled PECVD and at least one second sub-unit (48) for inductively coupled PECVD, and wherein the first sub-unit(s) (46) and the second sub-unit(s) (48) being arranged in an alternating manner along the handling path of the substrate (22).

2. Material processing machine (10) according to claim 1 , the first coating unit (14) and/or the second coating unit (16) comprising a drum (34, 36) for moving the substrate (22) along the handling path, the drum (34, 36) being cooled.

3. Material processing machine (10) according to claim 1 or 2, the first coating unit (14) and/or the second coating unit (16) being adapted to guide the substrate (22) along the handling path in a free span manner.

4. Material processing machine (10) according to any of the preceding claims , the first coating unit (14) comprising at least two first sub-units (46) and at least two second sub-units (48), the first sub-units (46) all being arranged in a first path section of the handling path and the second sub-units (48) all being arranged in a second path section of the handling path, the second path section following the first path section along the handling path of the substrate (22).

5. Material processing machine (10) for producing a multi-layered material (26) comprising a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the material processing machine (10) comprising a first coating unit (14) for applying the coating layer components comprising silicon oxide on the substrate (22) and a second coating unit (16) for applying the coating layer components comprising aluminum oxide on the substrate, wherein the first coating unit (14) and the second coating unit (16) are arranged along a handling path of the substrate (22), wherein the hybrid coating layer (38) is applied on the substrate (22) with a deposition rate of 20 nm/s or more, preferably of 35 nm/s or more.

6. Material processing machine (10) for producing a multi-layered material (26) comprising a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the material processing machine (10) comprising a first coating unit (14) for applying the coating layer components comprising silicon oxide on the substrate (22) and a second coating unit (16) for applying the coating layer components comprising aluminum oxide on the substrate, wherein the first coating unit (14) and the second coating unit (16) are arranged along a handling path of the substrate (22), wherein the silicon-providing first coating unit is arranged upstream of the aluminium-providing second coating unit.

7. Method for producing a multi-layered material (26) comprising a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide, the method comprising the following steps:

- providing a material processing machine (10) according to any of the preceding claims, - moving the substrate (22) at a predetermined processing speed along the handling path, thereby applying the hybrid coating layer (38) on the substrate (22); wherein the hybrid coating layer (38) is applied on the substrate (22) with a deposition rate of 20 nm/s or more, preferably of 35 nm/s or more.

8. Method according to claim 7, wherein the predetermined processing speed is 225 m/min or more, preferably 300 m/min or more.

9. Multi-layered material (26) comprising a substrate (22) and a hybrid coating layer (38) applied on the substrate (22), wherein the hybrid coating layer (38) comprises at least two coating layer components selected from the group of silicon oxide applied by capacitively coupled PECVD, silicon oxide applied by inductively coupled PECVD, aluminum and aluminum oxide.

10. Multi-layered material (26) according to claim 9, the multi-layered material (26) being obtained by the method according to any of claims 7 or 8.

11. Multi-layered material (26) according to claim 9 or 10, the hybrid coating layer (38) having a thickness in the range of 1 to 30 nm, preferably of 5 to 20 nm, particularly preferably of 8 to 15 nm.

12. Multi-layered material (26) according to any of claims 10 to 12, the multi-layered material (26) having a water vapour permeability of less than 2.0 g/(m² x 24 h), at 90 % relative humidity and 37.8 °C.

13. Multi-layered material (26) according to any of claims 9 to 12, the multi-layered material (26) having an oxygen permeability of less than 2.0 cm³/(m² x 24 h) at 50 % relative humidity and 23.0 °C.

14. Multi-layered material (26) according to any of claims 9 to 13, the substrate (22) being a continuous web or a discrete sheet.

15. Multi-layered material (26) according to any of claims 9 to 14, the substrate (22) comprising a polymer selected from the group of polyolefins, polyethylene terephthalate (PET), polylactic acid (PLA), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (PHB), cellophane, polyvinyl alcohol (PVOH) and/or ethylene vinyl alcohol (EVOH) and/or cellulose based material and/or a polyolefin, preferably polypropylene and/or polyethylene.