WO2004018198A2

WO2004018198A2 - Polyolefin multilayered film, method for the production of said film and use thereof

Info

Publication number: WO2004018198A2
Application number: PCT/EP2003/009077
Authority: WO
Inventors: Dirk Heukelbach; Ekkehard Beer; Wolfram Goerlitz
Original assignee: Ticona Gmbh
Priority date: 2002-08-21
Filing date: 2003-08-16
Publication date: 2004-03-04
Also published as: WO2004018198A3; AU2003255450A1; DE10238515A1; AU2003255450A8

Abstract

The invention relates to a polyolefin multilayered film having defined shrink properties, consisting of at least three layers, containing a) a core layer A acting as a base layer, consisting of at least one polyolefin and two surfaces layers B and C which are disposed on both sides and which are the same or different, consisting of at least one amorphous polyolefin having a Tg of 35 to 180 °C or b) a core layer A consisting of al least one amorphous polyolefin having a Tg of 35 to 180 °C and two surface layers B and C which are the same or different, consisting of at least one polyolefin. The polyolefin layers in a) and b) can also contain at least one amorphous polyolefin. One of the surface layers B and C in a) can also be mixed with at least one polyolefin. The invention also relates to a method for the production of said film and the use thereof.

Description

Polyolefin multilayer film, a process for producing this film and its use

The invention relates to a polyolefin multilayer film with defined shrink properties from at least three layers, comprising either a) a core layer A, which acts as a base layer, and consists of at least one polyolefin and two cover layers B and C on both sides, which are the same or different, made of at least one amorphous polyolefin with one T _g of 35 to 180 ° C or b) a core layer A made of at least one amorphous polyolefin with a T _g of 35 to 180 ° C and two outer layers B and C, which are the same or different, made of at least one polyolefin. The polyolefin layers in a) and b) can also additionally contain at least one amorphous polyolefin. One of the cover layers B and C in a) can also be mixed with at least one polyolefin. The invention further relates to a method for. Production of this film and its use.

Shrink films made of different polymers are often used as all-round labels, also called "sleeves", for plastic or glass containers, since they are easy to apply and after use of the container they are either discarded, separated or reprocessed together, i.e. recycled.

The shrink properties of the polymers used depend on many factors. For example, the shrinkage behavior of polymers, e.g. the change in length of oriented films - preferably "monoaxial for sleeves" - can be expressed as a function of pre-stretch in the elastic range, temperature or time, caused by the stretch and the temperature dependence of the elastic module in the glass transition area The glass transition temperature (T _g ) of the polymers mostly used in a mixture The occurrence of a single glass transition temperature is considered to be a measure of the miscibility of homogeneously miscible polymers, while two glass transition temperatures corresponding to those of the starting materials are observed in the case of immiscibility. For partially miscible polymers, two glass transition temperatures are observed, which differ slightly from those of the starting materials.

The influence of natural shrinkage is also important, since many of the polymers that can be used have a T _g below 0 ° C., which can lead to a malfunction during use. Particular attention should be paid to the storage conditions of the polymers to be processed. Uneven shrinkage can also affect the transparency of the labels, for example. In the event of a possible recovery, ie recycling of the polymers, the specific weight of both the substrate, ie the container, and the polymer must also be taken into account, so that a simple gravimetric separation by flotation or by air separation can take place perfectly. For a later separate reprocessing of container and "sleeve" material, the latter must additionally be miscible with the closure material (eg screw cap), since it occurs together with it in the recycling process. The temperature-dependent shrinkage curve is a measure of the processability of the films used. If the shrinkage curve drops steeply, foils can only be insufficiently shrunk onto unevenly shaped substrates, ie folds may occur or the foil tube does not adapt adequately to changing container diameters. For this reason, efforts have long been made to find a way to relate to the temperature to influence the elasticity module in the glass transition area and the shrinkage while at the same time maintaining transparency, while at the same time a low shrinkback force of the “sleeve” film should occur.

A shrinkable 3-layer film is known, composed of a low-density polyolefin (LDPE, LLDPE) as the core layer and a mixture of an amorphous cycloolefin polymer with a partially crystalline high-density polyolefin (HDPE), LDPE or LLDPE as the outer layers. Such a film can also be constructed from a mixture of a cycloolefin copolymer with a crystalline polyolefin as the core layer and a low-density polyolefin as the outer layers (JP 2000-202951 A2). The shrinkage of such a film at 80 ° C. is stated to be 20% or more. A shrinkage of up to 36% is mentioned in the examples. Notes on the shrinkback at other temperatures, the amount of the total shrinkback achievable and a possibility of dividing a desired shrinking curve course cannot be found in the document.

The object of the present invention is to avoid the disadvantages of the prior art.

The invention relates to a polyolefin multilayer film comprising at least three layers, comprising either a) a core layer A functioning as a base layer and comprising at least one polyolefin and two cover layers B and C on both sides, which are the same or different and consist of at least one amorphous polyolefin with a T _g from 35 to 180 ° C or b) a core layer A made of at least one amorphous polyolefin with a Tg of 35 to 180 ° C and two outer layers B and C, which are the same or different, made of at least one polyolefin. The polyolefin layers in a) and b) can also additionally contain at least one amorphous polyolefin. One of the cover layers B and C in a) can also be mixed with at least one polyolefin. The invention further relates to a method for producing this film and its use, which creates a new, significantly improved generation of "sleeve" films.

COC as a polyolefin with an amorphous character retains this property at every stage of processing, e.g. when melting, plasticizing, as a film, when stretching, and therefore does not take - like semi-crystalline materials, e.g. Polypropylene or polyester - by stretching in its crystallinity. It does not change its shrinking force and speed. COC remains stable in the non-shrinking direction during shrinkback, i.e. in contrast to other materials, there is generally no elongation or shortening transverse to the direction of shrinkage.

Through a combination of different polymers in a composite according to the invention, which is achieved by coextrusion, extrusion coating or lamination, the property profiles of the different polymeric materials are positively combined with one another. The additive film layers ensure a desired one Shrinkback in a large temperature range, e.g. from 35 to 180 ° C, the setting of a shrinkback - depending on the type and the proportion of the amorphous polyolefin - from 15 to 90% and a possibility of variably dividing a desired shrinkage curve course, this on a steep or flat course can be directed. In the present case, the influences of several polymers mixed with one another - homogeneously or inhomogeneously - can be used to advantageously convert the T _g point of the individual material into a T _g range. In this way, a shrinkage curve can be specifically adapted to the requirements of the application such as rigidity, shrinkage value, shrinkage temperature and shrinkage force. The addition of a polyolefin to an amorphous polyolefin also has an influence on the properties of the film composite, for example the fat resistance and flexibility, and thus increases the puncture resistance of the composite, with high transparency and good thermoformability at the same time. The properties of the film according to the invention also include sufficient rigidity so that when the film is intended to be used as “sleeves” it can be easily guided over the container used.

Not only are the physical and chemical properties improved, but it is also possible to achieve a reduction in the additive thickness of the entire film structure in order to achieve a significant reduction in the layer thickness and thus a cost saving, e.g. against a monofilm.

The amorphous polyolefins used are either used as individual components, ie they have a uniform glass transition point T _g , or as blends with different T _g 's. The influence of adding a polyolefin to the amorphous polyolefins has already been mentioned above. The proportion of the amorphous polyolefin in the respective layer is in the range from 20 to 100%, preferably 60 to 95%, in particular 70 to 90%.

The multilayer film according to the invention generally has a thickness of 20 to 80 μm, preferably 40 to 70 μm, after stretching. The are Layer thicknesses of the layers containing the amorphous polyolefins 20 to 70% of the total structure.

The amorphous polyolefin contained in the film according to the invention is preferably an amorphous cycloolefin polymer.

The cycloolefin polymer generally contains 0.1% by weight to 100.0% by weight, preferably 0.1% by weight to 99.9% by weight, based on the total mass of the cycloolefin copolymer, of polymerized units which are each other deriving from at least one polycyclic olefin of the formulas I, II, II ', III, IV, V or VI

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 are the} same or different and a hydrogen atom or a -C-C ₂ o-hydrocarbon radical, such as a linear or branched Ci-Cs- Alkyl radical, C ₆ -C ₈ aryl radical, C ₇ -C ₂ o-alkylene aryl radical, a cyclic or acyclic C ₂ -C ₂ o-alkenyl radical, or form a saturated, unsaturated or aromatic ring, the same radicals R ¹ to R ⁸ in the different formulas I to VI can have a different meaning, in which n can take on values from 0 to 5, and 0 to 99.9% by weight, preferably 0.1 to 99.9% by weight, based on the total mass of the cycloolefin copolymer, polymerized units which are derived from one or more acyclic olefins of the formula VII

9 11

10 _κ C = C. \ 12 m

R ..

in which R ⁹ , R ¹⁰ , R ¹¹ and R ^{12 are} identical or different and are a hydrogen atom, a linear, branched, saturated or unsaturated C ₁ -C _{2 (r} hydrocarbon radical such as a C ₈ -C ₈ alkyl radical or a C ₆ -C _{8 8} - Aryl radical mean.

In addition, the cycloolefin copolymers used can contain 0 to 45% by weight, based on the total mass of the cycloolefin copolymer, of polymerized units which are derived from one or more monocyclic olefins of the formula VIII

HC; CH (VIII)

(CH ₂ ) m

where m is a number from 2 to 10. The cyclic olefins also include derivatives of these cyclic olefins with polar groups such as halogen, hydroxyl, ester, alkoxy, carboxy, cyano, amido, imido or silyl groups.

For the purposes of the invention, preference is given to cycloolefin copolymers which contain polymerized units which are derived from polycyclic olefins of the formulas I or III, and polymerized units which are derived from acyclic olefins of the formula VII, in particular olefins having a norbornene basic structure such as norbornene and tetracyclododecene and optionally vinylnorbornene or norbornadiene.

Also preferred are cycloolefin copolymers with polymerized units derived from acyclic olefins with terminal double bonds, such as α-olefins having 2 to 20 carbon atoms, in particular ethylene or propylene, for example ethylene / norbornene and ethylene / tetracyclododecene copolymers.

Preferred terpolymers are ethylene / norbomene / vinyl norbornene, ethylene / norbomene / norbomadiene, ethylene / tetracyclododecene, vinyl norbornene, ethylene / tetracyclododecene / vinyltetracyclododecene or ethylene / norbomene / dicyclopentadiene terpolymers.

A copolymer of ethylene and norbomene can be used with particular advantage as the amorphous polyolefin.

The proportion of the polymerized units derived from a polyene, preferably vinyl norbornene or norbornadiene, is generally 0.1 to 50.0 mol%, preferably 0.1 to 20.0 mol%, the proportion of the acyclic Monoolefins of the formula VII are generally 0 to 99.9 mol%, preferably 5.0 to 80.0 mol%, based on the overall composition of the cycloolefin polymer. In the terpolymers described, the proportion of the polycyclic monoolefin is 0.1 to 99.9 mol%, preferably 3.0 to 75.0 mol%, based on the total composition of the cycloolefin polymer. The films according to the invention are generally transparent. However, they can also be produced by adding polymers which do not form a homogeneous mixture with the amorphous polyolefin or pigments as opaque, or soluble dyes as colored films.

The use of the amorphous polymer not only improves the sealability and slippage of the film, but also increases the color adhesion when writing or printing when it is used in the cover layers.

Of said polymers with typical plastic additives such as antioxidants, metal deactivators, light stabilizers, plasticizers, lubricants, processing aids, antistatic agents, optical brighteners, antibacterials, fire retardants, and fillers and reinforcing agents (see also Gächter, Müller, Plastics Additives Handbook, 4 edition mixtures ^th, 1993 , Munich, Hanser) are also suitable.

The cycloolefin copolymers can be prepared in a known manner at temperatures from -78 to 200 ° C. and a pressure of 0.01 to 200 bar, in the presence of one or more catalyst systems which contain at least one transition metal compound and optionally a cocatalyst and optionally a support material. Metallocenes, in particular stereorigid metallocenes, are suitable as transition metal compounds. Examples of catalyst systems suitable for the preparation of the cycloolefin copolymers are e.g. described in US-A-5,008,356, EP-A-0407870, EP-A-0485893 and EP-A-0 503 422, which are incorporated by reference.

The cycloolefin copolymers can also be prepared in other ways, briefly outlined below: Catalyst systems based on mixed catalysts composed of titanium salts and aluminum organyls are described in DD-A-109 224 and DD-A-237 070. EP-A-0 156 464 describes the production with vanadium-based catalysts. The cycloolefin copolymers can also be obtained by ring-opening polymerization of at least one of the monomers having the formulas I to VI and subsequent hydrogenation of the products obtained.

The polymerization can also be carried out in several stages, and block copolymers can also be formed (DE-A-42 05 416).

Amorphous polyolefins are understood to mean those polyolefins which, despite an irregular arrangement of the molecular chains at room temperature, are solids. They are essentially non-crystalline and their degree of crystallinity is generally below 5%, preferably below 2%, or is 0%, determined by X-ray if fractometry. The heat resistance of the cycloolefin copolymers can be adjusted over a wide range. The glass transition temperature for cycloolefin copolymers, measured in accordance with DIN EN ISO 11357-1 with the aid of a DSC, can be used as a guide for the heat resistance, as can be determined on injection moldings in accordance with ISO 75 Part 1 and Part 2. The cycloolefin copolymers described have glass transition temperatures in the range from 35 to 180 ° C., preferably from 50 to 170 ° C., in particular from 55 to 140 ° C.

The average molecular weight of the cycloolefin copolymers can be controlled in a known manner by metering in hydrogen, varying the catalyst concentration or varying the temperature. The cycloolefin copolymers contained in the films have average molecular weights Mw in the range from 500 to 2,000,000 g / mol, preferably from 1,000 to 1,000,000 g / mol, in particular from 3,000 to 500,000 g / mol. These molar masses determined with the aid of gel permeation chromatography (GPC) \ n chloroform at 35 ° C. with the aid of an Rl detector are relative and relate to a calibration with narrowly distributed polystyrene standards.

According to DIN 53 728, the cycloolefin copolymers described have viscosity numbers of 5 to 5,000 ml / g, preferably 5 to 2,000 ml / g and in particular 5 to 1,000 ml / g. The density of the cycloolefin copolymers used in the present invention is usually in the range from 0.9 to 1.1 g / cm ³ , preferably 0.9 to 1.05 g / cm ³ . The density of the multilayer film produced therefrom generally has a value of <1.0 g / cm ³ , preferably 0,9 0.98 g / cm ³ . This makes it possible to separate a film used as a shrink film according to the invention in a known manner, for example by flotation or wind sifting, from a substrate, for example PET, which acts as a carrier (for example container), ie to recycle both materials. Materials such as polyvinyl chloride, polystyrene and polyester, which are also used in practice as shrink films, cannot be separated or can only be removed with great effort using these processes.

Suitable polyolefins which can be used in the film according to the invention are high or low density polyethylenes (HDPE, LDPE, LLDPE), ethylene-vinyl acetate copolymer, ionomer, polypropylene, olefin copolymers, plastomers or mixtures thereof. _

There are embodiments which additionally have adhesion-improving layers applied between the individual layers. The substances used for this can contain at least one or more polymers and are generally known. The film waste resulting from the manufacturing process and all of its components can also be used for this purpose and thus reused. This can significantly improve economy and reduce environmental pollution.

The adhesion-improving layer can advantageously be applied in the melt or as a solution, suspension or solvent-containing adhesive.

The films according to the invention can be produced, for example, by a known process for producing a plastic multilayer film, in which the polymers and / or polymer mixtures forming the film are compressed in an extruder, heated and then the melt (s) are extruded through a flat die, which film thus obtained is drawn off on one or more rollers which Film is stretched and / or optionally heat set and / or surface treated.

The additives that may be added can already be contained in the polymer or in the polymer mixture or can be added via masterbatch technology.

A flat film obtained in this way is then generally stretched transversely to the direction of extrusion for the “sleeve” application, which leads to an orientation of the molecular chains. In this case, preferably in a ratio of 3: 1 to 8: 1 on a frame - inline or offline - worked.

The melt (s) can also be extruded through an annular die, the film thus obtained being processed into a film on a blown film system using the so-called “double bubble” process and laid flat on rollers and the film optionally being heat-set and / or surface-treated In this process, it is necessary for the "sleeve" production to carry out the transverse stretching to be carried out monoaxially.

A monoaxial longitudinal stretching has only a subordinate meaning in the case of the "sleeve" material. However, if required, a monoaxial longitudinal orientation, for example for battery labels, with the same stretching ratio can be advantageous. Here, this stretching is expediently carried out with the aid of two or more according to the desired stretching ratio Carry out rollers running at different speeds.

The shrinkage properties of the film are set by stretching. Shrinkage in the direction not previously stretched does not occur. There is also no change in the length of the film.

A heat setting (heat treatment) can then be carried out, the film being held for about 0.5 to 10 seconds at temperatures below the respective T _g 's, preferably 10 ° C. below. The film is then wound up in a conventional manner using a winding device. The take-off roll or rolls, on which the extruded film is cooled and solidified in the cast film process, is usually kept at a temperature of 20 to 90 ° C.

The temperature at which cross stretching is performed can vary. In general, it is carried out at 35 to 150 ° C, preferably 80 to 120 ° C - adapted to the respective T _g 's.

If necessary, one or both surface (s) of the film can be corona or flame treated by known methods.

Treating the surface prepares it for labeling or printing according to generally known methods.

The films obtained as flat films can also be glued into tubes in a conventional manner. ,

The films according to the invention can be used as shrink films because they shrink back in a large temperature range, for example from 35 to 180 ° C., the setting of a shrink back - depending on the shrinking temperature, the stretching factor, the stretching temperature and the proportion of the amorphous polyolefin - from 15 to 90% and a possibility of variably setting a desired shrinking curve course, which can be directed towards a steep or flat course. In general, shrinkage of up to 70% is aimed for in practice. The course of the shrinkage curve can be influenced in particular by using blends of the different amorphous polyolefins with different T _g 's, for example in order to enlarge the processing window. Furthermore, their shrinkage tension can be set in a range from 3 to 10 N / mm ² , preferably from 3.5 to 8 N / mm ² , particularly preferably from 4 to 6 N / mm ² . Due to the high puncture resistance of the composite with high transparency, good thermoformability and high rigidity, the film is excellently suited for use as all-round labels "sleeves" that can be easily passed over the container used. Examples 1 to 3; Comparative Examples V1 to V4

The following starting materials were used in Examples 1 to 3 below:

1. Ethylene-norbomene copolymer with a glass transition temperature Tg of 80 ° C and a viscosity number (VZ) of 80 ml / g (trade name © Topas 8007, Ticona GmbH, Frankfurt a. M.).

2. Ethylene-norbornene copolymer with a glass transition temperature Tg of 140 ° C and a VZ of 60 ml / g (trade name © Topas 6013, Ticona GmbH, Frankfurt am Main).

3.Polypropylene (trade name © Profax SR 727, Basell GmbH, Wesseling)

4. Polyethylene (trade name © Lupolex 18QFA, Basell GmbH)

5. Polyvinyl chloride (trade name © Genotherm GZ 48, Klöckner Pentaplast, Montabaur)

In accordance with the examples given in Table 1, films were produced from the materials mentioned by coextrusion or extrusion in the given strengths and stretched by a factor of 6 at the given temperatures. The change in length of these stretched films was then determined as a function of the temperature. The values for the shrinkage curves were determined under two different conditions. At the measuring points up to 90 ° C, storage of the foils in a water bath for 30 seconds was sufficient. For the measuring points above 90 ° C, the storage took place exclusively for 180 seconds in a circulating air drying cabinet on sand. The value for the shrinkage results from the difference in length before and after heat storage divided by the initial length. Table 1

X = percentage by weight of the COC mixtures (8007: 6013): 65: 35 The materials used are previously listed under 1. to 5.

Table 2 summarizes the results of the shrinking curve of the individual examples:

Table 2

T _A = temperature when shrinking 10% [° C] T _E = temperature when shrinking 70% [° C] ΔT = difference T _E - T _A [K]

The course of the shrinkage curve is important because it enables the sleeves to shrink evenly without interference, e.g. Wrinkles appear. ΔT is a measure, the statement of which reflects the steepness of the shrink curve. The value should be as large as possible in order to obtain a flat curve. A small ΔT value results in a steep curve. This gives the possibility of influencing the course of the curve by using suitable starting materials.

Example 1 clearly shows that the processing window is influenced by using blends from two different COCs, ie the value of ΔT is high. If a steeper course of the curve is desired, it is advantageous to use structures according to Examples 2 and 3. Here the shrinkback is already achieved at somewhat lower temperatures. Due to the structure of the film according to Example 2, there is also a higher rigidity compared to Example 3. Example 1 also shows a flatter course of the shrinkage curve compared to comparative examples 3 and 4. In addition, compared to comparison 3, there is a significant reduction in the COC content due to the three-layer structure with the same film thickness. Comparative examples 1 and 2 have a steep curve.

Examples 4 to 6; Comparative examples V5 and V6

The following starting materials were used in the following examples:

1. Ethylene-norbomene copolymer with a glass transition temperature Tg of 65 ° C and a viscosity number (VZ) of 95 ml / g (trade name: © Topas 9506, Ticona GmbH, Frankfurt a. M.).

2. Ethylene-norbomene copolymer with a glass transition temperature Tg of 80 ° C and a VZ of 80 ml / g (trade name: © Topas 8007, Ticona GmbH, Frankfurt a. M).

3. Polypropylene (trade name: © Profax SR 727, Basell GmbH, Wesseling).

4. Polyethylene (trade name: © Lupolex 18QFA, Basell GmbH, Wesseling).

From the materials mentioned, films were produced in the given thicknesses by coextrusion or extrusion in accordance with the examples given in Table 3 and stretched by a factor of 6 at the given temperatures. The change in length of these stretched films was then determined as a function of temperature. The values for the shrinkage curves were determined when the films were stored for 30 seconds in a water bath. The value for the shrinkage results from the difference in length before and after heat storage divided by the initial length. The shrinkage stress in [N / mm ² ] was measured at a temperature of 100 ° C. in a circulating air drying cabinet.

Table 3

The results of the shrinking curve profile of the individual examples 4 to 6 and V5 and V6 are summarized in Table 4 below:

Table 4

* extrapolated from the curve slope

TA = temperature when shrinking 10% [° C] T _E = temperature when shrinking 70% [° C] ΔT = difference T _E - T _A [K]

The table 5 below summarizes the values for the shrinkage tension, which were measured on the films of Examples 4 to 6 and V5 and V6 in a forced air oven at a temperature of 100 ° C.

Table 5

The measurement results shown above clearly show how the choice of the structure of the film (mono film or multilayer film) and the use of Mixtures of COC and other polyolefins, a steep or flat course of the shrinkage curve (Δ T large or small) can be specifically set and how the shrinkage tension of the films can be optimally adapted to the respective requirements in practice.

Claims

claims

1) Polyolefin multilayer film made of at least three layers, characterized in that it consists either of a) a core layer A which acts as a base layer and consists of at least one polyolefin and two cover layers B and C on both sides, which are the same or different, made of at least one amorphous polyolefin with one T _g from 35 to 180 ° C or from b) a core layer A consists of at least one amorphous polyolefin with a T _g of 35 to 180 ° C and two outer layers B and C, which are the same or different and consist of at least one polyolefin.

2) Film according to claim 1, characterized in that the polyolefin layers in a) and b) additionally contain at least one amorphous polyolefin.

3) Film according to claim 1 or 2, characterized in that one of the cover layers B and C in a) additionally contains at least one polyolefin.

4) Film according to one or more of claims 1 to 3, characterized in that the amorphous polyolefin is an amorphous cycloolefin polymer.

5) Film according to one or more of claims 1 to 4, characterized in that the cycloolefin polymer 0.1 wt .-% to 100.0 wt .-%, preferably 0.1 wt .-% to 99.9 wt .-% %, based on the total mass of the cycloolefin copolymer, contains polymerized units which are derived from at least one polycyclic olefin of the formulas I, II, IT, III, IV, V or VI

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 are the} same or different and a hydrogen atom or a -C-C ₂ o-hydrocarbon radical, such as a linear or branched Cι-C ₈ Alkyl radical, C ₆ -C ₈ aryl radical, C ₇ -C ₂₀ alkylene aryl radical, a cyclic or acyclic C ₂ -C ₂ o-alkenyl radical, or form a saturated, unsaturated or aromatic ring, the same radicals R ¹ to R ⁸ in the different formulas I to VI have a different meaning, in which n represents values from 0 to 5, and 0 to 99.9% by weight, preferably 0.1 to 99.9% by weight, based on the total mass of the cycloolefin copolymer, polymerized units which are derived from one or more acyclic olefins of the formula VII, formula VII

9 11

_/ C ^ C _X (Vil)

R -

wherein R ^9, R ^10, R ¹¹ and R ¹² are identical or different and saturated or unsaturated _{Cι-C2o-Kohlenwasserstoffrestwie} a -C ₈ alkyl radical or a C ₆ -C denote a hydrogen atom, a linear, branched aryl ₈ ,

6) Film according to claim 5, characterized in that the amorphous polyolefin is a cyclooie fin copolymer which contains 0 to 45 wt .-%, based on its total mass, of polymerized units which are derived from one or more monoolefinic olefins of the formula VIII

HC = CH (VIII)

derive, where m is a number from 2 to 10.

7) Film according to one or more of claims 1 to 6, characterized in that the layer thicknesses of the layers containing the amorphous polyolefins amount to 20 to 70% of the total structure

8) Film according to one or more of claims 1 to 7, characterized in that the amorphous polymer has a glass transition temperature T _g in the range from 35 to 180 ° C, preferably 50 to 170 ° C, in particular 55 to 140 ° C, and has an average molecular weight Mw in the range from 500 to 2,000,000, preferably 1,000 to 1,000,000, in particular 3,000 to 500,000.

9.) Film according to one or more of claims 1 to 8, characterized in that the density of the amorphous polyolefin in the range from 0.9 to 1.1 g / cm ³ , preferably 0.9 to 1.05 g / cm ³ , and the density of the film has a value of 1 1.0 g / cm ³ , preferably 0,9 0.98 g / cm ³ .

10) Film according to one or more of claims 1 to 9, characterized in that as polyolefins high or low density polyethylenes (HDPE, LDPE, LLDPE), ethylene-vinyl acetate copolymer, ionomer, polypropylene, olefin copolymers, plastomers or mixtures thereof are included.

11) Film according to one or more of claims 1 to 10, characterized in that it is recyclable.

12) Process for producing a polyolefin multilayer film from at least three layers, comprising either a) a core layer A made of at least one polyolefin and two outer layers B and C, which are the same or different, made of at least one amorphous polyolefin with a T _g of 35 to 180 ° C or b) a core layer A made of at least one amorphous polyolefin with a T _g of 35 to 180 ° C and two outer layers B and C, which are the same or different, made of at least one polyolefin, characterized in that they form the film Polymers and / or polymer mixtures compressed and heated in an extruder, then the Melt / s are extruded through a nozzle, the film thus obtained is drawn off on one or more rollers and stretched transversely or lengthwise.

13) Use according to one or more of claims 1 to 10 as a shrink film.

14) Use of the film according to claim 13 as all-round labels, "sleeves".

15) "Sleeves" made from the film according to one or more of claims 1 to 10.