DE102019119292B4 - Method for producing a mother roll of a coherent multilayer film and mother roll can be produced using such a method - Google Patents

Abstract

Method for producing a mother roll of a coherent multilayer film (2) from two outer layers (4, 6) and one or more inner layers (8) in between, all layers lying on top of each other and being connected to one another via lamination, in which the first outer layer (4) is fed to a laminating process by a first unwinding roll (10), an inner layer (8) is fed to the laminating process by a second unwinding roll (12), in the laminating process the first outer layer (4) with the inner layer (8) in a first gap (14 ) are pressed together between a first cooling roller (16) and a first counter-pressure roller (18) assigned to it, a laminator (20) being arranged above the gap (14), from which a liquid laminating composition (22) is placed between the gap (14 ) incoming layers (4, 8) is introduced, this laminating process is optionally continued with the film composite created in the previous laminating process and a further inner layer supplied by a further unwinding roller between further cooling rollers and further counter-pressure rollers assigned to them using further laminators until the desired number of inner layers lying one above the other is reached, the laminating process with the film composite (24) resulting from the previous laminating processes and the second outer layer (6) fed from a last unwinding roll (26) in a last gap (28) between a last cooling roller (30 ) and a last counter-pressure roller (32) assigned to this and with a laminator (34) arranged above the last gap (28) and the resulting multi-layer film (2) is rolled up to form a mother roll (36), characterized in that at least one of the Inner layers (8) are formed at least in two parts from two partial layers (8a, 8b) and these partial layers (8a, 8b) positioned next to each other within the multilayer film (2) form the inner layer (8), the at least two partial layers (8a, 8b) forming this Inner layer (8) for the laminating process of two different unwinding rollers (12a, 12b) arranged parallel but offset to one another are fed to a common gap (14) between a common cooling roller (16) and a common counter-pressure roller (18) assigned to it and the at least two Partial layers (8a, 8b) of at least one inner layer (8) are each formed by an aluminum foil.

Description

The invention relates to a method for producing a mother roll of a coherent multilayer film made of two outer layers and one or more inner layers in between, all layers lying on top of each other and being connected to one another via lamination. In the method, the first outer layer is fed from a first unwinding roll to a laminating process. An inner layer is fed to the laminating process by a second unwinding roll. In the laminating process, the first outer layer is pressed together with the inner layer in a first gap between a first cooling roller and a first counter-pressure roller assigned to it. A laminator is arranged above the gap, from which a liquid laminating composition is introduced between the layers entering the gap. This laminating process is optionally repeated with the film composite created in the previous laminating process and a further inner layer fed from a further unwinding roller between further cooling rollers and further counter-pressure rollers assigned to them using further laminators until the desired number of superimposed inner layers is reached. The laminating process is continued with the film composite resulting from the previous laminating processes and the second outer layer fed from a last unwinding roll in a gap between a last cooling roller and a last counter-pressure roller assigned to it, as well as with a laminator arranged above the gap, and the resulting multilayer film is rolled up into a mother roll .

Such lamination processes have been known and tested for many years. The material of the individual layers and the number of layers can be varied, as can the width of the multilayer film.

The US 4,413,406 A discloses a method for manufacturing a core of an electrical transformer. At the beginning of this process, several metal foils lying one on top of the other are connected to one another in selected areas to form a type of coherent foil. This film is then broken down into small plates using a cutting device.

The CN 104260541 A describes a method for producing a film consisting of a base film as the first layer and a transparent film and an aluminum film arranged next to it as a common second layer. With the two-layer film produced in this way, a packaging container can be produced by folding the film over and welding it, which has the transparent film on one side of the packaging, which can be printed and through which the goods preferred in the packaging are visible. The back of the packaging, however, is sealed light-tight by an aluminum film.

The US 2012/0255761 A1 discloses a flexible ribbon cable that has a layer sequence 1/2/7/3/2/1, where 1 is for a polymeric insulation layer, 2 is each for an adhesion promoter layer, 3 is each for an adhesive layer and 7 is for a layer consisting of several layers that are spaced apart in a defined manner Metal strips, in particular made of aluminum, which run parallel to one another in the longitudinal direction of the ribbon cable and are embedded between the adhesive layers.

The DE 26 43 838 B1 also discloses a ribbon cable in which a number of ribbon-shaped electrical metal strips are embedded in insulating material at a defined distance parallel to one another. The ribbon cable is composed of two polyester films provided with an adhesive layer, which are arranged on both sides of the metal strips and are firmly adhered to each other and to the metal strips. The adhesive layers are made from a liquid adhesive composition. The metal strips are preferably made of copper.

The DE 25 06 262 A1 discloses a laminated flat heating element that includes two outer layers and a plurality of conductor wires that are parallel to one another and spaced apart in a defined manner. The conductor wires are each connected to both outer layers using an adhesive and are made of aluminum.

The invention is based on the object of providing a method of the type mentioned at the outset for producing a multilayer film, which is more flexible to individual requirements for the resulting multilayer film. The invention is also based on the object of providing a mother roll of a multilayer film which can be produced using such a method.

The invention is achieved by a method of the type mentioned at the outset, in which at least one of the inner layers is formed in at least two parts from two partial layers and these partial layers positioned next to one another within the multilayer films form the inner layer. The at least two partial layers of this inner layer are fed to a common gap between a common cooling roller and a common counter-pressure roller assigned to it for the laminating process by two different unwinding rollers arranged parallel to one another but offset. This design makes it possible that Within a multilayer film there is an inner layer in the layer structure, which consists of two partial layers positioned next to one another within the layer, whereby these partial layers can differ from one another in material, orientation and/or also in their width. Furthermore, the distance between the partial layers can be varied. The at least two partial layers of at least one inner layer are each formed by an aluminum foil.

Aluminum foil is sold by a variety of manufacturers in standard widths of up to around 1,300 mm. Larger widths are only offered by a few manufacturers. For example, only a single supplier can deliver a width of more than 2,000 mm in the desired quality, in the thickness of 6 to 15 µm required for aluminum foil.

By feeding an inner layer from two unwinding rolls arranged parallel but offset from one another, the films of which are then positioned next to each other in partial layers within the multilayer film to form the inner layer, multilayer films with an aluminum layer can be produced with standard aluminum foils in larger widths in one pass and rolled up into parent rolls. The parent rolls are then cut into narrower customer rolls. This leads to an expansion of the capacity of the production system that works with the method according to the invention.

In a preferred embodiment of the method according to the invention, the at least two partial layers of aluminum foil each have a shiny and a matt surface. At least one of the partial layers is introduced into the gap with an orientation of the shiny side touching the cooling roller or the counter-pressure roller and at least one further partial layer is introduced into the gap with an opposite orientation, the matt side touching the cooling roller or the counter-cooling roller.

The foil composite emerging from the gap then has the two partial layers of aluminum foil with an outer side of the aluminum foil facing away from the foil composite. This outside is therefore shiny in one partial layer and matt in at least another partial layer made of aluminum foil. This makes it possible to respond to individual customer requests. One customer may want the glossy surface facing the first outer layer and another customer may want the glossy surface facing the second outer layer. The method according to the invention allows both customer requests to be met in a single production process, thereby saving time. The mother roll is then simply separated into two or more customer rolls, separating the two partial layers of aluminum foil and the layers above and below.

A mother roll of a multilayer film according to the invention also has the same advantage and can be produced using one of the aforementioned methods, in which at least one inner layer consists of at least two partial layers of aluminum foil with a shiny and a matt side, the aluminum foils being in the multilayer film with respect to the matt and shiny sides are oppositely oriented.

Advantageously, at least two partial layers directly adjacent to one another are introduced into the gap at a defined distance from one another, so that they are also spaced from one another in the multilayer film formed. When separating a mother roll with such a multilayer film produced according to the invention into at least two customer rolls, the multilayer film or the mother roll is separated from one another by two mutually parallel cuts across the mother roll and thus along the multilayer film. The middle edge trim is discarded. The aforementioned embodiment of the method according to the invention now results in less of the at least one inner layer with the two partial layers being present in the area of this central edge trim, since these partial layers have a defined distance from one another. The distance is particularly preferably of course smaller than the two parallel cuts to one another and thus than the width of the middle edge trim to be disposed of. Both customer roles then each have one of the partial layers. The process therefore means that less material in the form of part of the inner layer has to be disposed of unused. This is particularly relevant both economically and ecologically in the case that the two partial layers consist of aluminum foil. The middle edge trimming then has less aluminum foil than if the entire inner layer had been formed from a single aluminum foil in a conventional manner.

A mother roll of a multilayer film according to the invention also has the same advantage and can be produced using one of the aforementioned methods, in which at least one inner layer consists of at least two partial layers positioned next to one another, these partial layers being spaced apart at a defined distance.

In an advantageous embodiment of the method, at least two partial layers of at least one inner layer have different widths. This makes it possible to use the process to produce a mother roll from the multilayer film, which is in below Customer rolls of different widths can be separated and either consist of different inner layers and/or less inner layer has to be disposed of as waste in the area of the middle edge section.

In a particularly preferred embodiment of the invention, the liquid laminating composition essentially consists of a thermoplastic, in particular polyethylene or polypropylene. Essentially consisting of means that common additives can be added to the thermoplastic(s), but do not have to be added.

• 1 eine Prinzipskizze einer Vorrichtung, die mit dem erfindungsgemäßen Verfahren arbeitet in der Aufsicht und
• 2 die Prinzipskizze aus 1 in einer Darstellung von der Seite, zusätzlich den Verlauf der Lagen illustrierend.

The method according to the invention is discussed in more detail below using schematic sketches. Show it:

• 1 a schematic sketch of a device that works with the method according to the invention in supervision and
• 2 the basic sketch 1 in a representation from the side, also illustrating the course of the layers.

Elements of the invention with the same effect are given a uniform reference number below, if this makes sense. The features described below can also be the subject of the invention individually or in other combinations.

1 shows a schematic sketch of a device to illustrate the method according to the invention in top view and 2 shows this schematic sketch in side view.

In the process for producing a multilayer film 2 from two outer layers 4, 6 and one or more inner layers 8 in between, all layers 4, 6, 8 lie on top of each other and are connected to one another via lamination. The first outer layer 4 is fed to a laminating process by a first unwinding roll 10. An inner layer 8 is fed to the laminating process by a second unwinding roller 12. In the laminating process, the first outer layer 4 is pressed together with the inner layer 8 within a first gap 14 between a first cooling roller 16 and a first counter-pressure roller 18 assigned to it. A laminator 20 is arranged above the gap 14, from which a liquid laminating composition 22 is introduced between the layers 4, 8 entering the gap.

Only one inner layer 8 is provided in the schematic drawing. If further inner layers are desired, the aforementioned laminating process can optionally be continued with the film composite created in the previous laminating process and a further inner layer returned by a further unwinding roller between further cooling rollers and further counter-pressure rollers assigned to these, using further laminators, until the desired number superimposed inner layers is achieved.

The laminating process is then carried out with the film composite 24 resulting from the previous laminating processes and the second outer layer 6 supplied by a last unwinding roll 26 in a last gap 28 between a last cooling roller 30 and a last counter-pressure roller 32 assigned to it and with one above the last gap 28 Laminators 34 continued.

In the basic drawings, the first gap 14 between the first cooling roller 16 and the first counter-pressure roller 18 and the last gap 28 between the last cooling roller 30 and the last counter-pressure roller 32 assigned to it are each designed to be wider than is the case in practice, so that the Positioning of the counter-pressure rollers also in the top view 1 can be recognized. In practice, the distance between the cooling roller and the counter-pressure roller corresponds approximately to the thickness of the films introduced into the gap and the laminating composition applied.

The resulting multilayer film 2 is rolled up into a parent roll 36. A mother roll 36 is a rolled-up multilayer film 2 which is later separated into two or more customer rolls of the desired width.

At least one of the inner layers 8 is formed at least in two parts from two partial layers 8a, 8b. These partial layers 8a, 8b form the inner layer 8 positioned next to one another within the multilayer film 2. The at least two partial layers 8a, 8b of this inner layer 8 are used for the laminating process of two different unwinding rollers 12a, 12b arranged parallel but offset to one another in a common gap 14 between one common cooling roller 16 and a common counter-pressure roller 18 assigned to this.

In the exemplary embodiment, the at least two partial layers 8a, 8b consist of aluminum foil and each have a shiny surface 38 and a relatively matt surface 40. One of the partial layers 8a is positioned in the gap with the shiny side 38 touching the cooling roller 16 or the counter-pressure roller 18 14 introduced and the further partial layer 8b with an opposite orientation, the matt side, the cooling roller 16 or the Counter-pressure roller 18 is inserted touching into the gap 14.

In the exemplary embodiment, the two partial layers 8a, 8b that are directly adjacent to one another are inserted into the gap at a defined distance A from one another, so that they are also spaced apart from one another in the multilayer film 2 formed. The defined distance A is illustrated in the basic drawing by the distance A of the unwinding rollers 12a, 12b arranged parallel but offset from one another, which is still identical even in the event of a parallel displacement of the two rollers in such a way that the axes of rotation of the two unwinding rollers 12a, 12b coincide with one another is.

Reference numbers

2

Multilayer film

4

first outside layer

6

second outer layer

8th

Inner layer

8a

Partial position

8b

Partial position

10

first unwind roll

12

second unwind roll

12a

parallel but offset unwinding roller

12b

parallel but offset unwinding roller

14

first gap

16

first cooling roll

18

first counter pressure roller

20

Laminator

22

liquid lamination composition

24

resulting film composite

26

final settlement roll

28

last gap

30

last cooling roller

32

last counter pressure roller

34

Laminator

36

mother role

38

shiny surface of aluminum foil

40

matt surface of aluminum foil

A

defined distance

Claims (6)

Method for producing a mother roll of a coherent multilayer film (2) from two outer layers (4, 6) and one or more inner layers (8) in between, all layers lying on top of each other and being connected to one another via lamination, in which the first outer layer (4) is fed to a laminating process by a first unwinding roll (10), an inner layer (8) is fed to the laminating process by a second unwinding roll (12), in the laminating process the first outer layer (4) with the inner layer (8) in a first gap (14 ) are pressed together between a first cooling roller (16) and a first counter-pressure roller (18) assigned to it, a laminator (20) being arranged above the gap (14), from which a liquid laminating composition (22) is placed between the gap (14 ) incoming layers (4, 8) is introduced, this laminating process is optionally continued with the film composite created in the previous laminating process and a further inner layer supplied by a further unwinding roller between further cooling rollers and further counter-pressure rollers assigned to them using further laminators until the desired number of inner layers lying one above the other is reached, the laminating process with the film composite (24) resulting from the previous laminating processes and the second outer layer (6) fed from a last unwinding roll (26) in a last gap (28) between a last cooling roller (30 ) and a last counter-pressure roller (32) assigned to this as well as with a laminator (34) arranged above the last gap (28) and the resulting multi-layer film (2) is rolled up to form a mother roll (36), characterized in that at least one of the Inner layers (8) are formed at least in two parts from two partial layers (8a, 8b) and these partial layers (8a, 8b) positioned next to each other within the multilayer film (2) form the inner layer (8), the at least two partial layers (8a, 8b) forming this Inner layer (8) for the laminating process of two different unwinding rollers (12a, 12b) arranged parallel but offset to one another are fed to a common gap (14) between a common cooling roller (16) and a common counter-pressure roller (18) assigned to it and the at least two Partial layers (8a, 8b) of at least one inner layer (8) are each formed by an aluminum foil. Procedure according to Claim 1 , characterized in that the at least two partial layers (8a, 8b) made of aluminum foil each have a shiny (38) and a matt surface (40) and at least one of the partial layers (8a) with an Ori entation the shiny side (38) is inserted into the gap (14) touching the cooling roller (16) or the counter-pressure roller (18) and at least one further partial layer (8b) with an opposite orientation the matt side (40) the cooling roller (16) or the counter-pressure roller (18) is inserted touching into the gap (14). Method according to one of the preceding claims, characterized in that at least two partial layers (8a, 8b) directly adjacent to one another are introduced into the gap (14) at a defined distance (A) from one another, so that they are also in the multilayer film (2) formed. are spaced apart from each other. Method according to one of the preceding claims, characterized in that at least two partial layers (8a, 8b) of at least one inner layer (8) have different widths. Method according to one of the preceding claims, characterized in that the liquid laminating composition (22) consists essentially of a thermoplastic, in particular of polyethylene or polypropylene. Mother roll (36) of a multilayer film (2) can be produced using a method according to one of the preceding claims, in which at least one inner layer (8) consists of at least two partial layers (8a, 8b) of aluminum foil with a shiny (38) and a matt surface (40 ), characterized in that the aluminum foils are oriented oppositely with respect to the matt and shiny sides in the multilayer foil (2).

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