JP2002506755A - Thermoplastic polyesteramide film made of at least two layers and having improved bonding properties, method of making the same and use thereof - Google Patents

Abstract

  (57) [Summary] The present invention relates to multilayer films formed from different polyesteramides having different molecular structures. The polyesteramides may be biodegradable such that the entire multilayer film is also biodegradable. The multilayer film may be an unoriented film or a uniaxial or biaxially oriented film. In order to make it easier to process it, it may contain additives, which have shown improved bonding properties.

Description

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to thermoplastic films having at least two layers of polyesteramide.

[0002] Thermoplastic films made from polyesteramides are known, for example, from DE 44 44 948 or DE 196 32 799 (as part of a composite multilayer film). However, the sealing behavior of such single-layer films is not sufficient for many applications, and particularly the bonding strength is not sufficient.

[0003] Accordingly, an object of the present invention was to produce a polyesteramide film having improved bonding properties. The purpose of this is to use different molecular structures and therefore thermal properties (
thermal properties were achieved through making films having at least two layers made from different polyester amides. In this film, at least two layers are arranged so that the melting point of the polyester amide layer located on the outside is lower than that of the inner layer located directly adjacent thereto. Each layer may consist of a single polyesteramide or a mixture of several polyesteramides. For the purpose of better production or better further processing, it is also possible to add additional usual additives and auxiliary substances to the film. The production of the at least two-layer film is preferably carried out by an extrusion method. In addition, the at least two layers of film may then be subjected to uniaxial or biaxial orientation.

The ability of such polyesteramides to be processed thermoplastically and that improved bonding behavior is achieved in the case of unstretched or uniaxially or biaxially stretched films. Is surprising, which is the result of at least a two-layer structure formed from different polyesteramides. It is noteworthy that the stretched and unstretched films exhibit improved bonding properties as opposed to monolayer films, which means that the seam is deformed. Due to the low degree of occurrence and higher joint seam strength.

[0005] It is advantageous for the inner layer located directly adjacent to the outer layer to have a higher polyamide structure content than the polyamide structure content of the outer layer.

It is very particularly preferred for the film according to the invention to be a three-layer structure, in which case the melting point of the further inner (ie third) layer is again located directly adjacent to said outer layer. The inner layer is made lower than that of the inner layer, in particular, has the same composition as the outer layer.

The present invention provides a film having at least two layers, which may be unstretched or may be uniaxially or biaxially stretched, wherein the layers are made of different polyesters It consists of amides or of a mixture of several polyesteramides, and in addition, one or more of the above-mentioned layers contains 5 nucleating agents.
% By weight, conventional stabilizers and neutralizing agents in an amount of 5% by weight or less, and conventional lubricants and release agents in an amount of 5% by weight or less.
Wt% or less, and preferably the outer top layer.
rs) to conventional antiblocking agents
In an amount of 5% by weight or less.

In individual embodiments, additionally, a substance exhibiting corona and / or flame and / or plasma treatment and / or oxidizing action and / or a substance which can be added / adhered to the surface of said at least two layers of film and A mixture of substances exhibiting an oxidizing action and / or of a substance which can be added, for example a gas containing radical components, such as ozone, or a gas mixture excited by plasma [for example hexamethyldisiloxane and nitrogen (N ₂ ) and And / or a mixture of oxygen (O ₂ )]. If the film is to be stretched, the above-described preliminary surface treatment is preferably performed after orientation.

[0009] The uniaxial or biaxial orientation is carried out in the temperature range above the glass transition temperature in the case of amorphous thermoplastics and is partially crystalline.
In the case of a yeastline thermoplastic, it is higher than the glass transition temperature but has a crystallite melting temperature.
cure).

It is known that certain high molecular weight materials as well as certain polyesteramides can undergo biodegradation. Materials to be mentioned in this context are mainly those obtained directly from naturally occurring polymers or those obtained by modification thereof, such as polyhydroxyalkanoates, such as polyhydroxybutyrate, Plastic cellulose, cellulose esters, plastic starch, chitosan and pullulan, and the like. The specific alteration of the composition or structure of the polymer as desired in the sense of the application of the polymer is difficult, if possible, and often very limited due to natural synthetic processes. Only to the degree given. Within the scope of the present invention, the expression “biodegradable polymers and films” means that the material shows “biodegradability” when tested according to the test according to DIN V 54 900 of 1998. Should be understood as meaning.

On the other hand, many synthetic polymers are not attacked by microorganisms or are very slow, if at all. Primarily, synthetic polymers containing a heteroatom in the backbone are considered potentially biodegradable. Polyesters represent an important class within such materials. Synthetic raw materials containing only aliphatic monomers show relatively good biodegradability, but their use, if possible, is only to a very limited degree due to the material properties [Witt et al., Macrom Chem. Phys., 195 (1994) pp. 793-802]. On the other hand, aromatic polyesters exhibit good material properties, but their biodegradability is significantly poorer.

Various biodegradable polymers have recently become known (DE-443).
2 161). They are biodegradable while having the property of being easily processable thermoplastically, meaning that the entire polymer chain is cleaved by enzymes by microorganisms (bacteria and fungi) to completely eliminate Carbon, water and biomass (biomass)
). Corresponding tests carried out under the action of microorganisms in the natural environment, for example those found in compost in particular, are given in particular DIN V 54 900. Such biodegradable materials can be processed into semi-finished products, such as cast or blown films, in view of exhibiting the behavior of thermoplastics. However, the use of such semi-finished products is very limited. The difference when comparing such films to typical non-biodegradable plastics, such as polyethylene, polypropylene or polyamide, is that on the one hand the mechanical properties are poor and on the other hand the barrier properties for water vapor and gases are very low. It is inferior.

The invention also relates to the use of special polyamideamides or mixtures of such polymers, which can be biodegradable and compostable, in the production of multilayer films.

The aliphatic or partially aromatic polyester amides suitable for use according to the invention include the following monomers: I) difunctional aliphatic alcohols, preferably C ₂ to C ₁₀ linear dialcohols, for example Ethanediol, butanediol, hexanediol and the like, especially butanediol, and / or optionally a difunctional cycloaliphatic alcohol, preferably a bifunctional cycloaliphatic alcohol having 5 to 8 carbon atoms, such as cyclohexanedimethanol And / or in place of some or all of the diols, monomeric or oligomeric polyols based on ethylene glycol, propylene glycol or tetrahydrofuran or those having a molecular weight of 4,000 or less, preferably 1000 or less And / or the case of Smaller amounts of difunctional branched alcohols, preferably C ₃ -C ₁₂ - alkyl diols, such as neopentyl down chill glycols, and alcohols having a small amount of higher functionality optionally in addition, preferably C ₃ -C ₁₂ -alkyl polyols such as 1,2,3-propanetriol, trimethylolpropane and the like,
Bifunctional fatty acids, preferably having 2 to 12 carbon atoms in the alkyl chain, such as preferably succinic acid, adipic acid and the like, and / or optionally bifunctional aromatic acids, such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid Acids and optionally small amounts of higher functional acids, such as, for example, trimellitic acid, or II) acid- and alcohol-functionalized structural units (acid-and alcohol)
hol-functionalized structural units)
Acid- and alcohol-functionalized structural units, preferably having 2 to 12 carbon atoms in the carbon chain, such as hydroxybutyric acid, hydroxyvaleric acid, lactic acid or derivatives thereof, such as e-caprolactone or dilactide, or aromatic I) such that the group acid comprises no more than 50% by weight, based on the total acid
And / or copolymers of II) and III) difunctional aliphatic and / or cycloaliphatic amines which are amide components and / or optionally small amounts of difunctional branched amines (linear aliphatic If a small amount of higher functionality amines having (hexamethylenediamine in the amine, isophoronediamine, suitable especially hexamethylenediamine from C ₂ diamines to C ₁₀ are preferred) and the addition bifunctional line having a C ₅ or C ₆ ring if two in addition to some) functional linear and / or cyclic fatty acids, preferably from 2 carbon atoms in the alkyl chain of 12 with or cyclic fatty acids And / or cyclic fatty acids, preferably adipic acid, and / or optionally small amounts of difunctional branched and / or optionally difunctional aromatic acids, such as Phthalic acid, isophthalic acid,
Naphthalenedicarboxylic acid and the like, and optionally a small amount of a higher functionality acid, preferably a higher functionality acid having 2 to 10 carbon atoms, or IV) an acid which is an amide component and Amine-functionalized structural units, preferably acid- and amine-functionalized structural units having from 4 to 20 carbon atoms in the cycloaliphatic chain, preferably ω-laurinlactam, ε-caprolactam, in particular ε-caprolactam, Or a mixture of III) and IV) as the amide component, from which the ester components I) and / or II) comprise at least 3% by weight, based on the total amount of I), II), III) and IV), of the ester structure The amount (weight) is preferably from 5 to 70% by weight, the amount of amide structure is preferably from 95 to 30% by weight and the biodegradable polyester amide in a suitable form Ester component I) and / or II) is I) when the, II), III) and IV amounts of ester structure in at least 30 wt% total based on the) (weight) is preferably from 30 to 70% by weight
Is a polyesteramide made such that the amount of amide structure is preferably 70 to 30% by weight.

[0015] Polyesteramides suitable for use in accordance with the present invention are pure
It can be both a polyesteramide and a mixture of various polyesteramides.

Polyesteramides suitable for use in accordance with the present invention include nucleating agents typically used in polyesters, such as disodium 1,5-naphthalenesulfonate or layered silicates, such as talc, or Nucleating agents having a nanoparticle size, i.e., an average particle diameter of <1 [mu] m, such as titanium nitride, aluminum hydroxide hydrate
), A nucleating agent belonging to barium sulfate or zirconium compound etc.]
The following amounts may be added and the usual stabilizers and neutralizers
ng agents) may be added in amounts up to 5% by weight, conventional lubricants and release agents may be added in amounts up to 5% by weight, and conventional anti-blocking agents may be added in amounts up to 5% by weight.
% Or less, and possibly the surface may be subjected to a corona or flame or plasma treatment or may contain an oxidizing substance or substance mixture, such as a radical component such as ozone. Treatment with a gas or a gas mixture excited by a plasma [eg a mixture of hexamethyldisiloxane and nitrogen (N ₂ ) and / or oxygen (O ₂ )] may be used.

As the stabilizer and the neutralizing agent, compounds which exhibit a stabilizing action and are usually used in polyester compounds can be used. The amount of addition is reduced to 5% by weight or less.

Suitable stabilizers are, in particular, phenolic stabilizers, alkali metal / alkaline earth metal stearates and / or alkali metal / alkaline earth metal carbonates. The amount of phenolic stabilizer is preferably 0 to 3% by weight, especially 0.15 to 0.3% by weight, and its molar mass is 500 g
/ Mol or more is preferred. In particular, pentaerythrityl tetrakis-3 (3,5-di-t-butyl-4-hydroxyphenyl) -propionate or 1,3
Preference is given to 2,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl-4-hydroxybenzyl) -benzene.

The neutralizing agent is preferably dihydrotalcite, calcium stearate, calcium carbonate and / or has an average particle size of less than 0.7 μm and an absolute particle size of 10 μm.
m and a specific surface area of at least 40 m ² / g calcium montanate.

In a particularly preferred embodiment the film has a nucleating agent content of from 0.0001 to 2
% By weight and the content of stabilizers and neutralizers from 0.0001 to 2% by weight.

Lubricants and release agents include higher aliphatic amides, tertiary amines, fatty acid amides,
Higher fatty acid esters, low molecular weight polar-modified
Waxes, montan waxes, cyclic waxes, phthalates, metal soaps and silicone oils. Particularly, addition of higher fatty acid amide and silicone oil is appropriate.

Among the aliphatic amides, in particular, commercially available forms of ethyleneamide to stearylamide are suitable. Fatty acid amides are amides of water-insoluble monocarboxylic acids (so-called fatty acids) having 8 to 24 carbon atoms, preferably 10 to 18 carbon atoms. Among them, erucamide, stearamide and oleamide are preferred.

As the release agent or lubricant, a compound containing both an ester group and an amide group, for example, stearamide ethyl stearate or 2-stearamide-ethyl stearate is also suitable.

The expression “montan waxes” encompasses a wide variety of compounds. See Neumueller et al., Roempps Chemie-Lexikon, Franckh'sche Verlagshandlung, St.
See uttgart, 1974.

As the cyclic wax, for example, tetramethylene ester of adipic acid and 1,
Compounds such as 6-dioxa-2,7-dioxocyclododecane or homologous hexamethylene derivatives are suitable. Such substances are known as commercial products under the name Glycolbe VL.

Suitable silicone oils include polydialkylsiloxanes, preferably polydimethylsiloxane, polymethylphenylsiloxane, olefin-modified silicones, silicones modified with polyethers such as polyethylene glycol and polypropylene glycol, as well as Epoxyamino- and alcohol-modified silicon. Suitable silicone oil has a viscosity of 5000 to 1,000
2,000 mm ² / sec. Polydimethylsiloxane having a viscosity of 10,000 to 100,000 mm ² / sec is preferred.

[0027] The amount of lubricant added is up to 5% by weight. In a particularly preferred embodiment the film has a lubricant content of 0.005 to 4% by weight. In a very particularly preferred embodiment, the film has a lubricant content of 0.05 to 1% by weight.

[0028] Suitable anti-blocking agents are both inorganic and organic additives which project as protrusions from the surface of the film and thus provide a spacer effect.

In a preferred form the following substances: aluminum hydroxide aluminum hydroxide silicate, for example kaolin or kaolin clay aluminum oxide, for example Θ-aluminum oxide aluminum sulfate silica-aluminum oxide ceramic barium sulfate natural and synthetic silicas layered silicates For example, asbestos silicon dioxide calcite-type calcium carbonate calcium phosphate silicate magnesium carbonate magnesium oxide titanium dioxide zinc oxide glass microspheres is used as an inorganic anti-blocking agent, and is not compatible with the following biodegradable polymer: Organic polymers such as starch polystyrene polyamide polycarbonate crosslinked and uncrosslinked polymethyl methacrylate crosslinked polysiloxane (eg Tospearl) Ethylene (eg, polyethylene grafted with maleic anhydride) Polar modified polypropylene (eg, polypropylene grafted with maleic anhydride) Ethylene or propylene and vinyl alcohol or vinyl acetate or acrylic acid or acrylate ester or methacrylic acid or methacrylate A random copolymer based on a metal salt of an acrylate or methacrylic acid or a metal salt of methacrylic acid Benzoguanamine-formaldehyde polymer Aliphatic and partially aromatic polyester having a melting point different from the melting point of the raw material of the film Aliphatic polyester amide having a melting point different from the melting point of the film material Aliphatic polyester urethane having a melting point different from the melting point of the film material Different from the melting point of the film material Fat having that melting point - the aromatic polyester carbonates used as the organic anti-blocking agent.

[0030] Effective amounts of such anti-blocking agents are in the range of 5% by weight or less. In a particularly preferred embodiment, the film contains 0.005 to 4% by weight of an anti-blocking agent. In a very particularly preferred embodiment, the film is provided with an anti-blocking agent at 0.05%.
From 1% by weight. In particular, European Patent Application Publication No. 0 236 945
As described in U.S. Pat.
Spherical particles having an average particle size of 1 to 6 μm, in particular 2 to 5 μm, are suitable. It is also particularly appropriate to use various combinations of spacer systems. In a particularly preferred embodiment, such a spacer system is added to the outer top layer.

According to the method used hitherto, organic or inorganic fillers are added in the desired weight during the production of this raw material to the polymer for the film to which the additives are added. In the case where the raw material is granulated by, for example, a twin-screw extruder, the additive is added to the raw material. As with these types of additives, some or all of the necessary additives may also be used in the form of a masterbatch in the form of a raw material (to which raw materials may or may only be added additives). May be added). Within the scope of the present invention, the term “masterbatch” refers to the presence of a large amount of additives as an intermediate when preparing said composition (whether no or only some additives are added or not). Is to be understood as meaning a raw material mixture of the plastic raw materials used (as adding the material to the granules which have not been completely added), in particular a particulate concentrate which does not dust. This results in a film containing an amount of additive. Prior to introducing the polymer granules into an extruder, the masterbatch is added to a raw material to which no, only some, or not all additives have been added. Is added in such an amount that the desired amount (weight) of filler is achieved.

Suitable materials for use in the production of this masterbatch are, in addition to the additives, substances which are compatible with the polyesteramides described in the present invention.

With respect to the sub-groups of the biodegradable polyester amides, the materials used in the production of the masterbatch are in a particularly preferred form:
In addition to the additives, it is also a biodegradable material.

The corona treatment procedure advantageously involves a high voltage, usually an alternating voltage, such that a spray or corona discharge can occur between the electrodes while passing the film between two conductor elements acting as electrodes. (Approximately 5 to 20 kV and 5 to 30 kHz). Air present on the film surface is ionized by the spray or corona discharge and reacts with molecules on the film surface, resulting in additional polar incorporation into the polymer matrix.

In a flame treatment using a polarized flame (see US Pat. No. 4,622,237), a DC voltage is applied between the burner (negative electrode) and the cooling roller. The level of this applied voltage ranges from 400 to 3000V, preferably from 500 to 2000V. As a result of the application of the voltage, the ionized atoms undergo increased acceleration, which impinges on the surface of the polymer with higher kinetic energy. Radical generation proceeds more rapidly because the chemical bond in the polymer molecule is more easily broken. In this case, the thermal stress experienced by the polymer is much lower than the stress experienced in a standard flame treatment, and the treated surface has much better bonding characteristics than that of the untreated surface. Can be obtained.

In the case of the pre-plasma treatment, a gas such as oxygen, nitrogen, carbon dioxide, methane, a halogenated hydrocarbon, a silane compound, or a compound having a higher molecular weight, or a mixture thereof is converted into a high energy gas in a low pressure chamber. Field, for example, to microwave radiation. High-energy electrons are generated, which collide with the molecule and transfer its energy. As a result, a radical structure is locally generated and its excited state corresponds to a temperature of tens of thousands of degrees Celsius, but the temperature of the plasma itself is substantially room temperature. As a result, a chemical bond is broken and a motion reaction (motion reaction) is caused.
) (usually this can only occur at high temperatures). Monomer radicals and ions are formed. After the resulting monomer radicals (in some cases even in the plasma) form short-chain oligomers, which condense and polymerize on the surface to be coated. In this way, a uniform film adheres to the material to be coated.

However, before the radicals or ions of the monomer are attached to the substrate, the excited molecules may additionally have a so-called afterglow zone.
It is also possible to add further material flows in the glow zone). Thereby, a substance or a mixture of substances can be produced which causes an oxidative attack on the polymer substrate when it collides with the surface of the polymer film. A glass-like layer, often a highly cross-linked layer, adheres firmly to the surface of the film. With the appropriate material composition, this results in an increase in the surface tension of the film.

The production of the film of at least two layers according to the invention is preferably carried out by an extrusion process. The polyesteramide in particulate form is melted in an extruder, homogenized, compressed and then discharged through a multi-layer die. The dies may be tube dies if a seamless tubular film is to be produced. The film thus discharged or stretched, for example by means of a press roll, is then cooled until it solidifies. Cooling can be performed using either air or water or, alternatively, using cooling rollers. Cooling can be performed on one or both sides, and in the case of a tubular film the cooling may be on and off, or only on, or only on the outside. In addition, it is possible to obtain a flat, unstretched multilayer film by cutting one or both sides of the tubular film.

After cooling the tubular film formed as a primary tube as described above, it is further reduced, in the case of partially crystalline polyesteramide, to a temperature below the crystallite melting temperature. After conditioning and, in the case of amorphous polyesteramides, to a temperature above the glass transition temperature, it is subjected to biaxial stretching, ideally simultaneously. A particularly suitable method is a simultaneous biaxial stretching method using double-bubble technology,
In such a method, primary bubbles are stretched by applying pressure to the inside. For special adjustment of shrinkage properties, the film may then be subjected to a heat treatment. In such a fixing process, the film may be heated again to a temperature slightly lower than the crystallite melting temperature.

Thereafter, the tubular film may be subjected to an inner or outer surface treatment.

The present invention further provides a method for producing an extruded multilayer film according to the present invention,
The multilayer dice used in this method is in the form of a sheet die suitable for use in producing flat multilayer films. Thereafter, the discharged film is cooled until it solidifies. Cooling can be performed with a cooling roller using water.

After cooling the flat film, it is adjusted to a temperature below the crystallite melting temperature, in the case of a partially crystalline polyesteramide, and to its glass transition in the case of an amorphous polyesteramide. After adjusting to a temperature higher than the temperature, it may be subjected to uniaxial or biaxial stretching one or more times. After each stretching step, the fixing of the film may optionally be performed. After performing the stretching operation and optionally performing the fixing step, the finished film may optionally be subjected to an in-line pre-surface treatment.

The present invention further provides a uniaxial or biaxial stretching method for the film according to the present invention. Biaxial stretching is a simultaneous stretching process or a sequential two-step process (
In this case, the vertical stretching may be performed first, and then the horizontal stretching may be performed, or the horizontal stretching may be performed first, and then the vertical stretching may be performed.) A three-step process (where the longitudinal stretching may be performed first, followed by the lateral stretching, and finally the longitudinal stretching may be performed, or the lateral stretching may be performed first). A longitudinal stretching may be performed later and a lateral stretching may be performed last), or a sequential four-step process (in which case, the first longitudinal stretching is performed, followed by the horizontal stretching). And then a longitudinal stretching and finally a lateral stretching may be performed, or a longitudinal stretching may be performed first and then a longitudinal stretching. Can be carried out in the teeth carried out and then the transverse direction stretching and finally may be carried out longitudinal stretching). The fixing of the film may optionally take place after each individual stretching operation. Each such vertical and horizontal individual stretching operation can be performed in one or several steps.

[0044] Biaxial stretching of the film according to the invention in a preferred form is characterized in that it is a sequential process starting from longitudinal stretching.

In a further preferred embodiment, the uniaxial stretching of the film according to the invention is characterized in that the stretching ratio in the machine direction is from 1: 1.5 to 1:10.

In a further preferred embodiment, the uniaxial stretching of the film according to the invention is characterized in that the stretching ratio in the machine direction is from 1: 2.8 to 1: 8.

In a further preferred form, the biaxial stretching of the film according to the invention has a total stretching ratio in the machine direction of from 1: 1.5 to 1:10 and a total stretching ratio in the transverse direction of from 1: 2 to 1: 20.

In a further preferred form, the biaxial stretching of the film according to the invention has a total stretching ratio in the machine direction of from 1: 2.8 to 1: 8 and a total stretching ratio in the transverse direction of from 1: 3.8. 1:15.

The thickness of the film according to the invention in a preferred form is less than 500 μm.

The thickness of the film according to the invention in a further preferred form is less than 80 μm.
Therefore, it is advantageous for the thickness of the outer layer to be less than the thickness of the inner layer located immediately adjacent thereto. Particularly preferably, the thickness of the outer layer is between 5 and 20 μm and the thickness of the inner layer located directly adjacent thereto is between 20 and 40 μm. The thickness of the next inner layer, which may optionally be present, is again preferably between 5 and 20 μm.

The present invention furthermore relates to the use of a film according to the invention. Uses that come into consideration are the printed, unprinted or painted as well as pretreated or unpretreated forms of the film for packaging in the food and non-food fields. Multilayer film in pre-treated or unpretreated form as a multilayer film in certain forms or for protection and separation purposes related to cosmetics and hygiene products, such as baby diapers or sanitary towels Or as a card, paper and letter wind lining
Surface protection or surface fine adjustment in the field of window lining
as a multi-layer film with or without pre-treatment for refinement, or a finely-refined film (only with or without pre-treatment) Not only in a printed or unprinted form but also in a form provided with an adhesive, which can be used as a label or as an adhesive strip).

[0052] The multilayer films derived from the biodegradable polyesteramides may also be used as materials for greenhouse coverings or covering films in the horticultural and agricultural fields, or when finished to form bags, such as biological waste ( It can also be used in pre-treated or unpre-treated form for the purpose of storage and transport of the bio-waste, and in the present multilayer structure the molecular / crystal orientation and the coating /
The degradation rate can be adjusted through printing. In addition, the multilayer films composed of different polyesteramides show good permeability to oxygen, carbon dioxide and water vapor, which is particularly important when packaging fresh food. The biodegradability of individual polyesteramides can be a significant advantage for individual applications.

During the production and / or subsequent further processing of the film, a corona, flame, plasma, or another oxidizing substance or Substance mixtures, for example radical components,
For example, a pretreatment using a gas containing, for example, ozone or a gas mixture excited by plasma [for example, a mixture of hexamethyldisiloxane and nitrogen (N ₂ ) and / or oxygen (O ₂ )] is performed by reducing the surface tension. They may be received in such a way as to provide an improvement.

The present invention furthermore relates to the use of a multilayer film according to the invention as a coated film or a film composite. Other films included in the composite may be non-degradable films or biodegradable, compostable films. In addition, the coating materials or adhesives used may belong to both conventional non-degradable systems and to biodegradable and compostable raw materials.

In a particularly preferred form of use of the multilayer film according to the invention, the material used in the production of the coated film or of the film composite is such that the entire composite as well as DIN
Only substances that are biodegradable and can be composted according to V 54 900.

The present invention furthermore relates to the use of a multilayer film according to the invention as a starting material for producing a bag which releases its contents by degradation by a biodegradation process. Such bags can be produced not only by gluing but also by bonding the films, and such bags may be sealed bags or suitable closures or closures. Connector
ctor).

The present invention also provides a cooled or temperature controlled needle roller (need
The multilayer film or composite according to the present invention is used as a starting material when producing a packaging film or a separation film or a surface protection film having a very high water vapor transmission rate by piercing the film using a film. It also concerns the use. Such films are used for packaging water-releasing goods, such as bread or various kinds of fruits and plants, or as separation and protection films in the hygiene sector. Example 1 A two-layer film having structure AB was produced from two different polyesteramides belonging to the biodegradable polyesteramide subgroup with respect to structure. Material A [Bayer AG LP BAK 403-004, ie ε
60% by weight of an amide structure and 40% of an ester structure prepared by using 54% by weight of caprolactam, 23% by weight of adipic acid and 23% by weight of 1,4-butanediol.
% By weight of a polyester amide] (1 according to DIN 53 735).
(Measured at 90 ° C., 2.16 kg) is 7 (g / 10 min) and has a melting point (ISO 31
46 / C2) is 125 ° C., the lubricant content is 1% by weight and the antiblocking agent content is 0.1% by weight. Material B [Bayer LP
BAK 404-002, that is, 65% by weight of an amide structure and 35% by weight of an ester structure prepared by using 62% by weight of ε-caprolactam, 29% by weight of adipic acid, and 17% by weight of 1,4-butanediol. MFI (polyester amide)
According to DIN 53 735, measured at 190 ° C. and 2.16 kg) is 10 (g / 1
0 min), the melting point (measured according to ISO 3146 / C2) is 140 ° C., the lubricant content is 0.4% by weight and the antiblocking agent content is 0.1% by weight. After co-extrusion of the two-layer film, it was subjected to sequential biaxial stretching. The maximum extrusion temperature for material A was 180 ° C and the maximum extrusion temperature for material B was 190 ° C. The melt was cooled to a cooling roller frame with a casting roller having a roller temperature of 43 ° C. and a cooling roller having a roller temperature of 22 ° C.
and cooled as a flat film on the R frame. A thick solid film resulted, which was stretched in the next process step with rollers adjusted to a temperature of 82 ° C. and heated to the temperature. The actual stretching roller was operated at a temperature of 85 ° C. The flat film was subjected to longitudinal stretching in one step at a ratio of 1: 4.2. Next, after heating through the film, the temperature of the roller was set to 50 ° C. The pre-heating zone of the transverse stretching oven was adjusted to a temperature of 130 ° C. The actual temperature of the laterally stretched portion was 120 ° C. Within the section, the film was subjected to a lateral stretching in a ratio of 1: 4.6. In this way, a theoretical area stretch ratio of 1: 19.3 was obtained. The film after being subjected to the lateral stretching is heated to 105 ° C.
At a fixed temperature. The production rate at the outlet of the lateral stretching device is 18.
It was 0 m / min. A film having a thickness of 55 μm could be produced. Example 2 Processing the same biodegradable polyesteramides as the biodegradable polyesteramides of Example 1 under the processing conditions described in Example 1 yields a biaxially oriented 3-layer ABA film. I let it. In this case, a film having a total thickness of 80 μm was produced such that the polyesteramide having the lower melting point constituted the outer layer in order to achieve improved film bonding characteristics. Example 3 A three-layer ABA film was produced from the same biodegradable polyesteramides as in Examples 1 and 2 using a blown film apparatus.
The maximum extrusion temperature was 160 ° C. The melt is put into a multilayer ring die (multi
After draining through a layer ring die), it was cooled with air. The maximum die temperature was also set to 160 ° C. In this case, a film having a total thickness of 75 μm and a width of 500 mm was manufactured such that the polyesteramide having the lower melting point constituted the outer layer. Comparative Example Monolayer films were produced from the biodegradable polyesteramides of Examples 1, 2 and 3 (Material A) using a blown film apparatus. Maximum extrusion temperature of 160 ° C
I made it. The melt was discharged through a ring die and cooled with air. The maximum die temperature was also set to 160 ° C. In this case, the thickness is 95 μm and the width is 300 mm
Was produced.

The following physical properties were measured on the manufactured samples as follows: Mechanical properties: According to DIN 53 455, the mechanical values of the samples, tensile strength and elongation at tear, were measured in the machine and transverse directions. Measured in both directions. The modulus of elasticity in the machine and transverse directions is DIN 53 457
It was measured according to. The thickness of the individual samples was measured according to DIN 53 370. Permeability: The oxygen permeability of the sample was measured according to DIN 53 380 at a temperature of 23 ° C. at a relative humidity of 75%. Furthermore, the water vapor transmission rate is also DIN 531
Measured at a temperature of 23 ° C. at a relative humidity of 85% according to 22. Joint seam strength: The strength of the seam created using a joining machine with heated sealing tools on both sides was measured for the sample.
Bond strength is understood to be the maximum force required to separate the resulting bond seam under defined conditions (pressure, time, temperature). The joint seam is indicated by N and the width of the piece is added as an index (N / 15 mm). The bonding range is a temperature range in which a measurable bonding strength exists.

Two clean, intact test pieces were removed from the film width to be tested. For the purpose of bonding, they were held in such a way that the surface to be bonded was positioned above the other surface and that the samples protruded at least 1 cm from each side during the sealing jars. The bonding should be performed perpendicular to the running direction of the film.

The bond strength test was carried out according to the following standard conditions: pressure: 50 N / cm ² time: 0.5 s temperature: stepwise at 10 K starting from 150 ° C.

Using a test piece cutter, a test piece having a width of 15 mm was accurately cut from the center of the generated joint seam in the moving direction of the film. It was tested for joint strength through pulling apart perpendicular to the joint seam using a tensile tester.
In each case, the maximum value of the force generated at the time of separation is shown.

Table 1 shows the results of tests performed on the samples obtained in Examples 1, 2 and 3 and the comparative example.

[0063]

[Table 1]

──────────────────────────────────────────────────続 き Continuation of front page (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), OA (BF, BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, KE, LS, MW, SD, SL, SZ, UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR , BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS , JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZW. Le Amhang 1A F-term (Reference) 4F100 AK01C AK41A AK41B AK46A AK46B AL01A AL01B AL05A AL05B AT00C BA03 BA07 BA10A CA05A CA05B CA05H CA13A CA13B CA13H CA17A CA17H CA19A CA19B CA30E CA30E CAB GBE JAB GB30E JC00A JC00B JL12 YY00A YY00B 4F210 AA24 AG01 AG03 QA01 QC02 QC05 QC06 QG01 QG15 QG18 QK01 4J001 DA03 DB02 DB05 DC03 DC05 DC12 DC14 DD05 DD07 EB03 EB06 EB08 EB33 EB36 EC03 EC03 EC03 EC75

Claims (24)

[Claims] 1. The method of claim 1, comprising at least two layers substantially composed of at least one polyesteramide, wherein one, two or more or all of said layers are based on the total weight of the film. Optionally, nucleating agents are present in an amount of up to 5% by weight and conventional stabilizers and neutralizing agents in an amount of up to 5% by weight and conventional lubricants and release agents in an amount of up to 5% by weight. A thermoplastic film which may contain a normal anti-blocking agent in an amount of 5% by weight or less in at least one outer layer, wherein the melting point of the outer polyesteramide layer is higher than that of the thermoplastic film. A thermoplastic film having a melting point lower than that of an inner layer located immediately adjacent thereto. 2. The film according to claim 1, wherein the content of the polyamide structure in the inner layer located directly adjacent to the outer layer is higher than that of the outer layer. 3. The polyesteramide according to claim 1, wherein: I) a difunctional aliphatic alcohol, preferably a C ₂ to C ₁₀ linear dialcohol, such as ethanediol, butanediol, hexanediol and the like, especially butanediol, and / or Or optionally bifunctional cycloaliphatic alcohols, preferably C5-C8 bifunctional cycloaliphatic alcohols, such as cyclohexanedimethanol, and / or in place of some or all of said diols Monomeric or oligomeric polyols based on ethylene glycol, propylene glycol or tetrahydrofuran or their copolymers with a molecular weight of 4,000 or less, preferably 1000 or less, and / or optionally small amounts of bifunctional branches alcohols, preferably C ₃ -C ₁₂ - alkyl Geo Le, such neopentyl such emissions chill glycol, and alcohols having a small amount of higher functionality optionally in addition, preferably a C ₃ -C ₁₂ - alkyl polyols such as 1,2, 3-propanetriol, Bifunctional fatty acids, in addition to trimethylolpropane, etc.
Bifunctional fatty acids, preferably having 2 to 12 carbon atoms in the alkyl chain, such as preferably succinic acid, adipic acid and the like, and / or optionally bifunctional aromatic acids, such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid Acids and optionally small amounts of higher functional acids such as, for example, trimellitic acid, or II) acid- and alcohol-functionalized structural units, preferably having 2 carbon atoms in the carbon chain. To 12 acid- and alcohol-functionalized structural units, such as hydroxybutyric acid, hydroxyvaleric acid, lactic acid or derivatives thereof, such as ε-caprolactone or dilactide, or the aromatic acid is up to 50% by weight, based on the total acid I) and II so as to constitute the quantity of
III) difunctional aliphatic and / or cycloaliphatic amines and / or optionally small amounts of difunctional branched amines (linear aliphatic C ₂ To C ₁₀ diamines are preferred) and optionally small amounts of higher functional amines, of which hexamethylenediamine, isophoronediamine, especially hexamethylenediamine, are preferred. In addition to difunctional linear and / or cyclic fatty acids, preferably having 2 to 12 carbon atoms in the alkyl chain or, in the case of cyclic fatty acids, having a C ₅ or C ₆ ring and And / or cyclic fatty acids, preferably adipic acid, and / or optionally small amounts of difunctional branched and / or optionally difunctional aromatic acids, such as terephthalate Acid, isophthalic acid,
Naphthalenedicarboxylic acid and the like, and optionally a small amount of a higher functionality acid, preferably a higher functionality acid having 2 to 10 carbon atoms, or IV) an acid which is an amide component and Amine-functionalized structural units, preferably acid- and amine-functionalized structural units having from 4 to 20 carbon atoms in the cycloaliphatic chain, preferably ω-laurinlactam, ε-caprolactam, in particular ε-caprolactam, Or a mixture of III) and IV) as the amide component, from which the ester components I) and / or II) comprise at least 3% by weight, based on the total amount of I), II), III) and IV), of the ester structure The amount (weight) is preferably from 5 to 70% by weight, the amount of amide structure is preferably from 95 to 30% by weight and the biodegradable polyester amide in a suitable form Ester component I) and / or II) is I) when the, II), III) and IV amounts of ester structure in at least 30 wt% total based on the) (weight) is preferably from 30 to 70% by weight
3. A film according to claim 1 or 2, characterized in that it is a polyesteramide of an aliphatic or partially aromatic polyester made such that the amount of amide structure is preferably 70 to 30% by weight. 4. The film according to claim 1, wherein the polyesteramides can be both pure polyesteramides and mixtures of different polyesteramides. 5. The composition of claim 1, wherein one or more of the layers has a lubricant content in the range of 0.005 to 4% by weight, and preferably the outer lubricant has a lubricant content in the outer top layer. The film according to any one of claims 1 to 4, wherein the content of the blocking particles is in the range of 0.005 to 4% by weight. 6. The anti-blocking agent contained in one of the layers, two or more or all of the layers has a content of the lubricant in the range of 0.05 to 1% by weight and preferably in the outer layer. 6. The film according to claim 1, wherein the amount of the particles ranges from 0.05 to 1% by weight. 7. A three-layer film, characterized in that the further inner (third) layer has a lower melting point than that of the inner layer, which is again directly adjacent to the outer layer. Item 7. The film according to any one of items 1 to 6. 8. The film of claim 1, wherein the film has been longitudinally uniaxially stretched, and the stretched ratio of the longitudinally uniaxially stretched film is from 1: 1.5 to 1:10. 8. The film according to any one of 1 to 7. 9. The film according to claim 8, wherein the stretch ratio of the film subjected to the uniaxial stretching in the longitudinal direction is from 1: 2.8 to 1: 8. 10. The film has been subjected to a biaxial stretching and the total stretching ratio in the machine direction of the film subjected to the biaxial stretching is from 1: 1.5 to 1:10 and the total stretching ratio in the transverse direction. Is from 1: 2 to 1:20, the film according to any one of claims 1 to 7. 11. The film having undergone the biaxial stretching has a total stretch ratio in the machine direction of 1: 2.8 to 1: 8 and a total stretch ratio in the transverse direction of 1: 3.8 to 1:15. The film according to claim 10, wherein: 12. The film according to claim 10, wherein the biaxial stretching is performed in a sequential process starting from a longitudinal stretching. 13. The film according to claim 1, wherein the thickness of the film is less than 500 μm. 14. The film according to claim 1, wherein the thickness of the film is less than 80 μm. 15. The method according to claim 1, wherein the thickness of the outer layer is 5 to 20 μm and the thickness of the inner layer located immediately adjacent to the outer layer is 20 to 40 μm. Film. 16. The film according to claim 1, wherein all of the polyesteramide is biodegradable and can be composted. 17. The film according to claim 1, wherein the film contains an organic or inorganic pigment for coloring in at least one layer. 18. The pigment is biologically harmless and / or 1% by weight
18. The multilayer film of claim 17, wherein the film is present in an amount less than. 19. Use of the film according to any one of claims 1 to 18, for packaging in the food or non-food sector or for greenhouse coverings or covering films in the horticultural and agricultural sector or for forming bags. When finished, they are subject to pretreatment for material storage and transport, for protection and separation functions related to cosmetics and hygiene products, or for surface protection or surface fine-tuning in the fields of card, paper and letter wind lining. Printed as well as in uncoated or untreated form, as a multilayer film in unprinted or painted form, or provided with an adhesive, as a label, or Are printed or marked as well as pre-processed or non-pre-processed as adhesive strips Use as a fine-tuning film in unprinted form. 20. Use of a film according to any one of claims 1 to 18, wherein the film is coated with the same or different polyesteramide or with another non-biodegradable film. Use in producing composites or laminates. 21. The use of a film according to claim 20, wherein all of the films and coating materials and adhesives used in the composite or laminate or coated film are biodegradable and can become compost. 22. A method for producing at least a two-layer film according to any one of claims 1 to 18, wherein the polyesteramide is first melted by heat and shear and the resulting melt is obtained. A method comprising discharging an object from a tool in the form of a tubular or flat film and cooling until it solidifies. 23. After cooling the tubular film, in the case of a partially crystalline polyesteramide, adjust it to a temperature above the glass transition temperature but below the crystallite melting temperature; Adjusting it to a temperature above the glass transition temperature, allowing it to undergo one or more biaxial stretchings, and, after this stretching operation or a separate stretching operation, optionally fixing it, and said stretching and fixing 23. The method of claim 22, wherein after operation, it may optionally be subjected to a surface treatment. 24. After cooling the flat film, in the case of a partially crystalline polyesteramide, adjust it to a temperature above the glass transition temperature but below the crystallite melting temperature, and In some cases, after it is adjusted to a temperature above the glass transition temperature, it is subjected to one or more uniaxial or biaxial stretching and, after this or a separate stretching operation, it is optionally fixed, and 23. The method according to claim 22, wherein after the stretching and fixing operation, it may optionally be subjected to a surface treatment.