DE19811773A1 - Opaque, biodegradable and compostable film for packaging fruit and vegetables and for covering plants or greenhouses - Google Patents

Abstract

An opaque biodegradable and compostable film (I) is biaxially oriented and comprises a biodegradable and compostable polymer. The biodegradable and compostable polymer (I) comprises: (i) <= 5 wt.% nucleation agent; (ii) <= 5 wt.% conventional stabilizers and neutralization agents; (iii) <= 5 wt.% conventional lubricants and release agents; (iv) <= 5 wt.% anti-blocking agent; and (v) an inorganic filler. The nucleation agent or anti-blocking agent may be added to the inorganic filler to produce an opaque surface.

Description

The invention relates to a thermoplastic, biodegradable and composted bare opaque film.

The object of the present invention is to produce an opaque film which is biodegradable and compostable. This goal is achieved in that a film made of a biodegradable and compostable polymer or a Mixture of biodegradable and compostable polymers with up to 49 wt .-% of inorganic fillers are filled, produced and then is stretched monoaxially or biaxially. The film can be used for better manufacturing or be better equipped with additives for further processing.

It was surprising for the inventor that the inorganic fillers filled, biodegradable and compostable polymers in addition to the thermo plastic processing can also be oriented monoaxially or biaxially and the stretched opaque film through improved rigidity and thus improved mechanical properties as well as a glossy surface and opacity distinguished.

It is known that certain polymeric materials undergo biodegradation may be subject to. Mainly materials that are made of natural occurring polymers are obtained directly or after modification, for example polyhydroxyalkanoates such as polyhydroxybutyrate, plastic celluloses, Cellulose esters, plastic starches, chitosan and pullulan. A targeted variation of the Polymer composition or the structures, as on the part of the polymer is desirable because of the natural synthesis process only difficult and often only possible to a very limited extent. Under the terms "organic Degradable and compostable polymers or films "are in the sense of this Invention understood goods that according to the test according to DIN V 54 900 of  1998 certified the "biodegradability". According to DIN V 54 900, the The proportion of inorganic fillers is a maximum of 49% by weight.

Many of the synthetic polymers, however, are not or not by microorganisms attacked only extremely slowly. Mainly synthetic polymers, the hetero Atoms contained in the main chain are said to be potentially biodegradable viewed. Polyesters represent an important class within these materials. Synthetic raw materials that only contain aliphatic monomers have one relatively good biodegradability due to their material properties can only be used to a very limited extent; see Witt et al. in Macrom. Chem. Phys., 195 (1994) pp. 793-802. Aromatic polyesters, on the other hand, show good material properties significantly deteriorated biodegradability.

Various biodegradable polymers have been known recently (see DE 44 32 161). These have the property that they process well thermoplastic are editable and, on the other hand, biodegradable, d. H. all of them Polymer chain of microorganisms (bacteria and fungi) split by enzymes and be completely broken down into carbon dioxide, water and biomass. A appropriate test in a natural environment under the influence of micro organisms as u. a. prevails in a compost, is u. a. in DIN V 54 900 given. These biodegradable materials can due to the thermo plastic behavior can be processed into semi-finished products such as cast or blown films. However, the use of these semi-finished products is very limited. For one, stand out these films are characterized by poor mechanical properties and secondly they are Barrier properties with regard to water vapor and gases in comparison to films typical, but not biodegradable plastics such as polyethylene, poly propylene or polyamide very bad.

Suitable polymers for the film according to the invention are:
aliphatic or partially aromatic polyester

• A) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ di-alcohols such as ethanediol, butanediol, hexanediol or particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 or 6 carbon atoms in the cycloaliphatic ring, such as, for example Cyclohexanedimethanol, and / or partially or completely, instead of the diols, monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ -C ₁₂ - Alkyldiols, such as neopentyglycol, and additionally optionally small amounts of higher-functional alcohols, such as 1,2,3-propanetriol or trimethylolpropane, and from aliphatic bifunctional acids, preferably C ₂ -C ₁₂ -alkyldicarboxylic acids, such as, for example, and preferably succinic acid, ad ipinic acid and / or optionally aromatic bifunctional acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher functional acids such as trimellitic acid or
• B) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 C atoms in the alkyl chain, for example hydroxybutyric acid, hydroxy valeric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of A and B, where the aromatic acids do not make up more than 50% by weight, based on all acids;
aliphatic or partially aromatic polyester urethanes

• C) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ dialko, such as ethanediol, butanediol, hexanediol, particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably with a C ₅ - or C ₆ -cycloaliphatic ring, as in for example cyclohexanedimethanol, and / or partially or completely instead of the diols, monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ - C ₁₂ alkyl diols, such as neopentyglycol, and additionally optionally small amounts of higher-functional alcohols, preferably C ₃ -C ₁₂ alkyl polyols, such as, for example, 1,2,3-propanetriol or trimethylol propane, and from aliphatic bifunctional acids, preferably C ₂ -C ₁₂ -Alkyldicarbon acids, such as wise and preferably succinic acid, adipic acid, and / or optionally aromatic bifunctional acids such as, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher functional acids such as, for example, trimellitic acid or
• D) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 C atoms, for example hydroxybutyric acid, hydroxyvaleric acid, milk acid, or its derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of C and D, where the aromatic acids do not make up more than 50% by weight, based on all acids;

• E) from the reaction product of C and / or D with aliphatic and / or cycloaliphatic bifunctional and additionally optionally higher functionality isocyanates, preferably with 1 to 12 C atoms or 5 to 8 C atoms in the case of cycloaliphatic isocyanates, for. B. tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, optionally additionally with linear and / or branched and / or cycloaliphatic bifunctional and / or higher-functional alcohols, preferably C ₃ -C ₁₂ alkyldi- or polyols or 5 to 8 carbon atoms in the case of cycloaliphatic alcohols, e.g. B. ethanediol, hexanediol, butanediol, cyclohexanedimethanol, and / or optionally additionally with linear and / or branched and / or cycloaliphatic bifunctional and / or higher functional amines and / or amino alcohols with preferably 2 to 12 carbon atoms in the alkyl chain, for. B. ethylenediamine or aminoethanol, and / or optionally further modified amines or alcohols such as ethylenediamino ethanesulfonic acid, as a free acid or as a salt,

wherein the ester fraction C) and / or D) is at least 75% by weight, based on the sum of C), D) and E);
aliphatic or aliphatic-aromatic polyester carbonates

• F) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ di-alcohols such as ethanediol, butanediol, hexanediol or particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 to 8 carbon atoms in the cycloaliphatic ring, such as, for example Cyclohexanedimethanol, and / or partially or completely, instead of the diols, monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably with C. ₂ -C ₁₂ - Alkyldicarboxylic acids, such as neopentyglycol and additionally optionally small amounts of higher functional alcohols such as 1,2,3-propanetriol, trimethylolpropane and from aliphatic bifunctional acids such as and preferably succinic acid, adipic acid and / or optionally all aromatic bifunctional acids such as, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and, if appropriate, small amounts of higher functional acids such as, for example, trimellitic acid or
• G) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 C atoms in the alkyl chain, for example hydroxybutyric acid, hydroxy  valeric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of F and G, the aromatic acids making up no more than 50% by weight, based on all acids;

• H) a carbonate component, which is made from aromatic bifunctional phenols, before bisphenol-A, and carbonate donors, for example phosgene, or
  a carbonate portion which is made from aliphatic carbonic acid esters or their derivatives such as chlorocarbonic acid esters or aliphatic carboxylic acids or their derivatives such as salts and carbonate donors, for example phosgene, where

the ester fraction F) and / or G) is at least 70% by weight, based on the sum of F), G) and H);
aliphatic or partially aromatic polyester amides

• I) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ di-alcohols such as ethanediol, butanediol, hexanediol, particularly preferably butanediol, and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 to 8 carbon atoms, such as cyclohexanedimethanol , and / or partially or completely instead of the diols monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ - C ₁₂ alkyldiols, such as, for example, neopentyglycol and additionally optionally small amounts of higher functional alcohols, preferably C ₃ -C ₁₂ alkyl polyols, such as, for example, 1,2,3-propanetriol, trimethylolpropane and from aliphatic bifunctional acids, preferably with 2 to 12 carbon atoms in the alkyl chain, such as and before adds succinic acid, adipic acid and / or optionally aromatic bifunctional acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and, if necessary, small amounts of higher functional acids such as trimellitic acid or
• K) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 C atoms in the carbon chain, for example hydroxybutyric acid, Hy droxyvaleric acid, lactic acid, or their derivatives, for example ε-capro lactone or dilactide,

or a mixture and / or a copolymer of I) and K), where the aromatic acids do not make up more than 50% by weight, based on all acids;

• L) an amide portion of aliphatic and / or cycloaliphatic bifunctional and / or optionally small amounts of branched bifunctional amines, linear aliphatic C ₂ to C ₁₀ diamines are preferred, and additionally optionally small amounts of higher functional amines, among the amines preferably hexamethylenediamine, isophoronediamine and particularly be preferably hexamethylenediamine, and from linear and / or cycloaliphatic bifunctional acids, preferably with 2 to 12 carbon atoms in the alkyl chain or C ₅ - or C ₆ ring in the case of cycloaliphatic acids, preferably adipic acid, and / or optionally small amounts branched bifunctional and / or optionally aromatic bifunctional acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher functional acids, preferably with 2 to 10 carbon atoms, or
• M) from an amide component from acid and amine functionalized building blocks, preferably with 4 to 20 carbon atoms in the cycloaliphatic chain before increases ω-laurolactam, ε-caprolactam, particularly preferably ε-caprolactam,

or a mixture of L) and M) as the amide portion, the ester portion I) and / or K) is at least 30% by weight, based on the sum of I), K), L) and M), preferably the proportion by weight of the ester structures 30 to 70% by weight, the proportion of the amide structures is 70 to 30% by weight.

The polymers according to the invention can be both pure polymers and also act as mixtures of various of the polymers mentioned.

The invention also relates to the use of a specific one Class of materials for biodegradable and compostable polymers position of the film, this class of material being polyester amide. The film according to the invention can be made of a polyester amide or a mixture consist of various polyester amides.

The invention relates to an opaque film made of a polymer or Mixture of different polymers that are organic according to DIN V 54 900 degradable and compostable and filled with inorganic fillers so that the fillers may have a maximum content of 49% by weight. For in the event that DIN V 54 900 does not have to be met, the proportion of inorganic fillers greater than 49% by weight, preferably less than 85% by weight, be. The inorganic fillers are distributed in the polymer matrix and have one maximum particle diameter of 60 µm (D 98%) and a medium particle diameter less than or equal to 15 µm (D 50%).

In a particularly preferred form, the inorganic fillers used have a maximum particle diameter of 30 µm (D 98%) and an average Particle diameter less than or equal to 6 µm (D 50%).

The invention relates to an opaque film made of polymers or a mixture of different polymers which are biodegradable and compostable and enriched with inorganic fillers, the inorganic fillers in a preferred form being chalk. The chalk used consists for the most part (at least 94% by weight) of CaCO ₃ (Textbook of Inorganic Chemistry; Holleman, AF, Wiberg, E .; de Gruyter-Verlag 1985). MgCO ₃ and Fe ₂ O ₃ generally occur as further inorganic constituents, but they have a significantly lower proportion than CaCO ₃ .

The fillers can both by a masterbatch, the content of fillers is correspondingly high, so that the film has the desired content of fillers has, as well as by compounding directly with the polymer or polymers mixed and then processed. Under the term masterbatch is in Understanding a masterbatch within the scope of the present invention, in particular a granular, dust-free concentrate of a plastic raw material with high Amounts of fillers and / or other additives that are used in bulk preparation Intermediate product is used (as a material additive to a non or only granules partially or incompletely equipped with fillers or additives), in order to produce films with a certain amount of fillers and / or Additives included. The masterbatch is made before filling in the polymer granulate in the extruder in such amounts to the not or only partially or raw materials incompletely mixed with fillers or additives, so that the desired weight percentages of fillers are realized in the films become.

The invention relates to an opaque film made of polymers with inorganic Fillers can be filled and stretched both biaxially and monoaxially and additionally with a maximum of 5% by weight of nucleating agents and a maximum of 5% by weight of the usual stabilizers and neutralizing agents and a maximum of 5 wt .-% of the usual Contains lubricants and release agents as well as a maximum of 5% by weight of the usual antiblocking agents. The nucleating agents or antiblocking agents can also be added to the inorganic ones Fillers count and also create an opaque surface.

In a special form, the opaque film according to the invention can additionally be treated with a corona and / or flame and / or plasma pretreatment and / or an oxidative substance and / or a depositable / depositable substance and / or a mixture of substances with an oxidative effect and / or attachable substances, e.g. B. gases with radical components such as ozone or a plasma-excited gas mixture of, for example, hexamethyldisiloxane with nitrogen (N ₂ ) and / or oxygen (O ₂ ), are treated on the surface. The surface pretreatments mentioned are preferably carried out according to the monoaxial or biaxial orientation.

The monoaxial or biaxial orientation takes place with amorphous thermoplastics in Temperature ranges above the glass transition temperature as well as with partially crystalline Thermoplastics above the glass transition temperature and below the crystallite melting temperature.

The film according to the invention can contain a maximum of 5% by weight of a nucleating agent typically used for polyester (for example 1,5-naphthalene disodium sulfonate or layered silicates, for example talc, or nucleating agents of nanoparticle size, ie average particle diameter <1 μm, of for example titanium nitride, aluminum hydroxyl hydrate, barium sulfate or zirconium compounds) and with a maximum of 5% by weight of the usual stabilizers and neutralizing agents and with a maximum of 5% by weight of the usual lubricants and release agents and a maximum of 5% by weight of the usual antiblocking agents, and possibly with a corona or flame - or plasma treatment or an oxidative substance or mixture, e.g. B. gases with radical components such as ozone or a plasma-excited gas mixture of, for example, hexamethyldisiloxane with nitrogen (N ₂ ) and / or oxygen (O ₂ ), can be treated on the surface.

The usual stabilizers can act as stabilizers and neutralizing agents the compounds are used for polyester compounds. The additional amount is a maximum of 5% by weight.

Phenolic stabilizers, alkali / earth, are particularly suitable as stabilizers alkali stearates and / or alkali / alkaline earth carbonates. Phenolic stabilizers in an amount of 0 to 3 wt .-%, in particular 0.15 to 0.3 wt .-% and with a  Molar mass of more than 500 g / mol preferred. Pentaerythrityl-Tetrakis-3 (3,5-di- Tertiary butyl 4-hydroxyphenyl) propionate or 1,3,5-trimethyl-2,4,6-tris (3,5-di- Tertiary butyl-4-hydroxybenzyl) benzene are particularly advantageous.

Neutralizing agents are preferably dihydrotalcite, calcium stearate, calcium carbonate and / or calcium montanate with an average particle size of at most 0.7 µm, an absolute particle size of less than 10 µm and a specific surface area of at least 40 m ² / g.

In a particularly preferred embodiment, the film has one Nucleating agent content of 0.0001 to 2 wt .-% and a stabilizer and Neutralizing agent content from 0.0001 to 2 wt .-%.

Lubricants and release agents are higher aliphatic amides, tertiary amines, aliphatic Acid amides, higher aliphatic acid esters, low molecular polar modified Waxes, montan waxes, cyclic waxes, phthalates, metal soaps and silicone oils. The addition of higher aliphatic acid amides and Silicone oils.

The aliphatic amides include, in particular, the available forms of ethylene suitable from amide to stearylamide. Aliphatic acid amides are what amides Ser insoluble monocarboxylic acid (so-called fatty acids) with 8 to 24 carbon atoms, preferably 10 to 18 carbon atoms. Erucic acid amide, stearic acid amide and oleic acid amide are preferred among them.

Compounds which are both ester and as well as amide groups, such as stearamide ethyl stearate or 2 Stear amido ethyl stearate.

A number of different verbs fall under the name Montan waxes fertilize. See Neumüller et al. in Römpps Chemie-Lexikon, Franckh'sche Publishing house, Stuttgart, 1974.  

Examples of cyclic waxes are components such as cyclic adipic acid tetramethylene ester or 1.6-dioxa-2.7-dioxocyclododecane, or the homologous hexa suitable methylene derivative. Such substances are known as commercial products Glycolube VL known.

Suitable silicone oils are polydialkylsiloxanes, preferably polydimethylsiloxane, polymethylphenylsiloxane, olefin-modified silicone, silicone modified with polyethers such as, for. B. polyethylene glycol and polypropylene glycol and epoxyamino- and alcohol-modified silicone. The viscosity of the suitable silicone oils is in the range from 5000 to 1,000,000 mm ² / s. Polydimenthylsiloxane with a viscosity of 10,000 to 100,000 mm ² / s is preferred.

The amount of lubricant added is at most 5% by weight. In a be a particularly preferred embodiment of the film has a lubricant component from 0.005 to 4% by weight. In a very particularly preferred embodiment of the The film has a lubricant content of 0.05 to 1% by weight.

Suitable antiblocking agents are both inorganic and organic additives, which protrude from the film surface as an elevation and thus a distance cause holder effect. The nucleating agents or antiblocking agents can be added to the count inorganic fillers and also create an opaque surface.

In a preferred form, the following substances or mixtures of these substances are used as inorganic fillers, which can also serve as anti-blocking agents, the mixtures generally being natural occurrences (e.g. chalk, talc, etc.) :
Aluminum hydroxide
Aluminum silicates, for example kaolin or kaolin clay,
Aluminum oxides, for example Θ-aluminum oxide
Aluminum sulfate
Ceramics made of silica aluminum oxides
Barium sulfate
natural and synthetic silicas
Layered silicates,
Silicon dioxide
Calcium carbonate of the calcite type
Calcium phosphate
Magnesium silicates
Magnesium carbonate
Magnesium oxide
Titanium dioxide
zinc oxide
Micro glass balls,
and used the following substances as organic antiblocking agents:
organic polymers incompatible with the biodegradable polymer such as
Strength
Polystyrene
Polyamides
Polycarbonates
cross-linked and uncross-linked polymethyl methacrylate
cross-linked polysiloxane (e.g. Tospearl)
polar modified polyethylene (e.g. maleic anhydride grafted polyethylene)
polar modified polypropylene (e.g. maleic anhydride grafted polypropylene)
statistical copolymer based on ethylene or propylene with vinyl alcohol or vinyl acetate or acrylic acid or acrylic acid ester or methacrylic acid or meth acrylic acid ester or metal salts of methacrylic acid or metal salts of meth acrylic acid ester
Benzoguanamine formaldehyde polymers
aliphatic and partially aromatic polyesters with different melting points than the film raw material
aliphatic polyester amides with different melting points than the film raw material
aliphatic polyester urethanes with different melting points than the film raw material
aliphatic-aromatic polyester carbonates with different melting points than the film raw material.

The effective amount of antiblocking agent is up to a maximum of 5% by weight. In In a particularly preferred embodiment, the film contains 0.005 to 4% by weight of anti blocking agent. In a very particularly preferred embodiment, the film contains 0.05 up to 1% by weight of antiblocking agent. The average particle size is between 1 and 6 µm, in particular 2 and 5 microns, wherein particles with a spherical shape, as in the EP-A-0 236 945 and DE-A-38 01 535 are described, are particularly suitable. Combinations of different spacer systems are also particularly suitable.

According to the processes used so far, the polymers are made for those with additives provided film in the raw material production with the desired weight amounts equipped with organic or inorganic fillers. This happens with the Granu the raw material, for example in twin-screw extruders, where the raw material Additives are added. In addition to this type of additive, there is also Possibility that some or all of the necessary additives are not or only partially equipped raw material can be added in the form of a masterbatch.

The preferred materials from which the masterbatches are used in addition to the additives are substances that ver with the polymers mentioned in this invention are inert.

In a particularly preferred form, the materials from which in addition to the Additives that Masterbatches are made, also biodegradable and compostable or biologically harmless or neutral.

In corona treatment, the procedure is expediently such that the film is passed between two conductor elements serving as electrodes, wherein such a high voltage between the electrodes, mostly alternating voltage (about 5 to 20 kV and 5 to 30 kHz), that spray or corona discharges take place can find. The air is above the by the spray or corona discharge  Film surface ionizes and reacts with the molecules of the film surface, see above that additional polar inclusions arise in the polymer matrix.

For a flame treatment with polarized flame (see US-A-4,622,237) one DC electrical voltage between a burner (negative pole) and a cooling roller applied. The applied voltage is between 400 and 3000 V, preferably it is in the range of 500 to 2000 V. By the applied The ionized atoms are subjected to increased acceleration and are also affected greater kinetic energy on the polymer surface. The chemical bonds within the polymer molecule are broken up more easily and the radical formation is faster. The thermal load on the polymer is far greater less than with standard flame treatment, and films can be obtained where the sealing properties of the treated side are even better than that that of the untreated side.

In a plasma pretreatment, gases, e.g. B. Oxygen or nitrogen or carbon dioxide or methane or halocarbon serstoffe or silane compounds or higher molecular compounds or also Mi of this, a high-energy field, e.g. B. microwave radiation set. High-energy electrons are created that hit the molecules and transfer their energies. This creates local radical structures, their Excitation states correspond to temperatures of several tens of thousands of degrees Celsius although the plasma itself is almost at room temperature. As a result the possibility of breaking chemical bonds and reactions going on set that can normally only take place at high temperatures. Make it up themselves monomer radicals and ions. Form from the resulting monomer radicals themselves - sometimes already in plasma - short-chain oligomers, which are then loaded onto the condensing and polymerizing layered surface. On the coating material a homogeneous film separates as a result.

However, before the monomer radicals or ions deposit on the substrate, there is also the option of in the so-called after-glow zone  add another material flow to the excited molecules. This is it possible to create a substance or a mixture of substances that when encountered the polymer film surface he an oxidative attack in the substrate polymers testifies. A glass-like and mostly highly cross-linked layer is formed, which with the Foil surface is firmly connected. With a suitable composition, the result is this causes an increase in the surface tension on the film.

The invention also relates to the process for producing an opaque, biodegradable and compostable film. The opaque film according to the invention is expediently produced using an extrusion process. The degradable and compostable materials (as compound or as unfilled polymer with the addition of an appropriate masterbatch) in granular form are melted in extruders, homogenized, compressed and discharged using a tool, cooled until solidification, then with partially crystalline materials at crystalline melting temperature and tempered above the glass transition temperature and, in the case of amorphous materials, above the glass transition temperature and then stretched one or more times monoaxially or biaxially. After the stretching process or processes, the film can optionally be fixed in each case. After the stretching processes and the possibly prevailing fixing stages, the film thus produced can possibly be surface-pretreated in-line. The pretreatment can be carried out with a corona, a flame, a plasma or an oxidative substance or mixture of substances, e.g. B. gases with free radical components such as ozone or a plasma-excited gas mixture of, for example, hexamethyl disiloxane with nitrogen (N ₂ ) and / or oxygen (O ₂ ), so that there is an increase in the surface tension on the film.

The invention also relates to a method for monoaxial or biaxial stretching of the film according to the invention. The biaxial stretching can in the simultaneous stretching process or in the two-stage sequential process, whereby so probably first stretched longitudinally and then laterally as well as first stretched later and then longitudinally can be, or in a three-step sequential process, both first stretched lengthways, then lengthways and finally lengthways as well as lengthways first, then lengthways and  can be stretched laterally, or in four-step sequential Process, both first longitudinal, then transverse, then longitudinal and final stretched across as well as crosswise, then lengthways, then crosswise and finally lengthways can be stretched. Every single stretch can possibly connect a fixation of the film. The individual stretching in longitudinal and The transverse direction can take place in one or more stages.

In a preferred form of the film according to the invention, the biaxial stretching is characterized in that it is a sequential method that with the longitudinal stretching begins.

In an even more preferred form of the film according to the invention, the film is monoaxial Drawing characterized in that the stretching ratio in the longitudinal direction 1: 1.5 to 1:10.

In an even more preferred form of the film according to the invention, the film is monoaxial Drawing characterized in that the stretching ratio in the longitudinal direction 1: 2.8 to 1: 8.

In an even more preferred form of the film according to the invention is the biaxial one Drawing characterized in that the total drawing ratio in the longitudinal direction tion 1: 1.5 to 1:10 and the total transverse stretch ratio 1: 2 to 1:20 is.

In an even more preferred form of the film according to the invention is the biaxial one Drawing characterized in that the total drawing ratio in the longitudinal direction ratio 1: 2.8 to 1: 8 and the total transverse stretch ratio 1: 3.8 to 1:15 is.

In an even more preferred form of the film according to the invention, it has one Thickness that is less than 500 microns.  

In an even more preferred form of the film according to the invention, it has one Thickness that is less than 80 microns.

The invention also relates to the use of the invention Foil. As an application comes the use of these opaque, biodegradable and compostable film in pretreated or untreated as well as in printed or unprinted form for packaging in the food and Non-food or as an opaque, biodegradable and compostable film in pretreated or untreated form for protection and separation functions in the Connection with cosmetics and hygiene articles, for example for baby diapers or sanitary napkins or as an opaque, biodegradable and compostable film in pretreated or untreated form for surface protection or Surface finishing in the field of cardboard and paper lamination or as refined film that is in pretreated or untreated as well as printed or unprinted form and provided with adhesive as a label or adhesive strip can be used.

The opaque, biodegradable and compostable film can also be used traded or untreated form for greenhouse covers or for off clothing of plant growing boxes (e.g. for mushroom cultivation) in the areas Horticulture and agriculture find their application, whereby the content of inorganic fillers the biological and by buffering the the hydrolytic degradation rate can be controlled.

The invention also relates to the use of the invention opaque, biodegradable and compostable film as coated film or in a film composite. The other films in the composite may be involved non-degradable films or also biodegradable and compostable films act. In addition, the coating or adhesive used can both to the normal non-degradable systems as well as to the biodegradable ones and compostable raw materials.  

In a particularly preferred form of use of this invention Opaque, biodegradable and compostable films are used to manufacture the coated film or a film composite only such substances used that the Overall composite also biodegradable and compostable according to the DIN V 54 900 is.

The invention also relates to the use of the invention opaque, biodegradable and compostable film as the starting material for the production of a bag that after decay by the biological Degradation process releases its contents. The pouch can be glued through as well Sealing of the film can be made and both closed and a Have an opening with an appropriate closure or connection.

The invention also relates to the use of the invention opaque, biodegradable and compostable film or composites as a finish material for the production of a packaging or separating or surface protective film with very high water vapor permeability, by this film with a cold or tempered needle roller is pierced. The purpose of this Foil is the packaging of moisture-releasing goods, such as bread or different types of fruit or vegetables, or as a release and protective film in Hygiene area.

example 1

A polyester amide (40% by weight chalk) filled with chalk (OMYA BL, OMYA GmbH Cologne, content of CaCO ₃ <98%, MgCO ₃ <0.52%, Fe ₂ O ₃ <0.02%) Film made with a thickness of 200 microns. The unfilled form of the polyester amide has an MFI of 7 (in g / 10 min at 190 ° C, 2.16 kg, measured according to DIN 53 735), a melting point of 125 ° C (measured according to ISO 3146 / C2) Lubricant content of 1% by weight and an antiblock content of 0.1% by weight. The maximum extrusion temperature was 190 ° C. The melt was discharged as a blown film from an annular die, cooled, cut and wound up as a flat film. The flat film was then simultaneously stretched biaxially in the longitudinal and transverse directions at a stretching temperature of 110 ° C. with a ratio of 1: 2. This resulted in a calculated area stretch ratio of 1: 4. A sample with a thickness of 110 μm could be produced.

Example 2

The same material from Example 1 was used for the same procedure biaxially stretched pattern at the stretching temperature of 110 ° C and a longitudinal and A transverse stretching ratio of 1: 3 was produced. This resulted in a mathematical calculation Area stretch ratio of 1: 9. A sample with a thickness of 60 µm could be obtained getting produced.

Example 3

The same material from Example 1 was used for the same procedure monoaxially stretched pattern at the stretching temperature of 110 ° C and one Longitudinal stretch ratio of 1: 4 produced. It could be a pattern with a thickness of 85 µm can be produced.  

Comparative example

The same material from Example 1 was used with a blown film extruder undrawn blown film with a thickness of 50 microns.

The following physical properties such as measured as follows:

Mechanical properties

The mechanical parameters of tensile strength and elongation at break were determined on the samples determined in both the longitudinal and transverse directions according to DIN 53 455. The E- The module in the longitudinal and transverse directions was measured in accordance with DIN 53 457. The thickness of the individual samples was determined in accordance with DIN 53 370.

Permeation properties

The permeability of oxygen at a temperature of 23 ° C and a relative humidity of 75% according to DIN 53 380 measured. Farther was the permeability of water vapor at a temperature of 23 ° C and a relative humidity of 85% determined according to DIN 53 122.

shine

The surface gloss of the samples was measured in accordance with DIN 67 530. The regular reflected light component is referred to as a gloss, based on a less than 20 ° referred to the incident light beam. The gloss is in gloss units GE, which are based on a black glass standard.

The results of the tests on the samples from Examples 1, 2 and 3 and the Comparative examples are listed in Table 1.  

Table 1

Claims (30)

1. Opaque, biodegradable and compostable film, characterized in that it has a biaxial orientation and consists of one or all filled with inorganic fillers, biodegradable and compostable polymer and with a maximum of 5 wt .-% nucleating agents and a maximum of 5 wt .-% of the usual stabilizers and neutralizing agents and a maximum of 5 wt .-% of the usual lubricants and release agents and a maximum of 5 wt .-% of the usual antiblocking agents, the concentration information being based on the total mass of the film. The nucleating agents or antiblocking agents can also count among the inorganic fillers and likewise produce an opaque surface. 2. Film, according to claim 1, characterized in that the proportion of anorga African fillers can be from 1% by weight to a maximum of 49% by weight. 3. Foil, according to claim 1, characterized in that the proportion of anorga fillers can be from 49% by weight to a maximum of 85% by weight, if DIN V 54 900 does not have to be met. 4. Film, according to claim 1 to 3, characterized in that it is in the or the polymers
aliphatic or partially aromatic polyester

• A) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ dialcohols such as, for example, ethanediol, butanediol, hexanediol or particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 or 6 carbon atoms in the cycloaliphatic ring, such as, for example, cyclohexanedimethanol , and / or partially or completely instead of the diols monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ -C ₁₂ -alkyldiols, such as neopentyglycol, and additionally optionally small amounts of higher-functional alcohols, such as 1,2,3-propanetriol or trimethylolpropane, and from aliphatic bifunctional acids, preferably C ₂ -C ₁₂ -alkyldicarboxylic acids, such as, for example and preferably succinic acid, Adipic acid and / or optionally aromatic bifunctional acids such as terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher functional acids such as trimellitic acid or
• B) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 carbon atoms in the alkyl chain, for example hydroxybutter acid, hydroxyvaleric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of A and B, where the aromatic acids make up no more than 50% by weight, based on all acids;
aliphatic or partially aromatic polyester urethanes

• C) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ dialcohols such as, for example, ethanediol, butanediol, hexanediol, particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably with a C ₅ - or C ₆ -cycloaliphatic ring, such as, for example, cyclohexanedimethanol , and / or partially or completely instead of the diols monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ -C ₁₂ alkyldiols, such as neopentyglycol, and additionally optionally small amounts of higher-functional alcohols, preferably C ₃ -C ₁₂ -alkyl polyols, such as 1,2,3-propanetriol or trimethylolpropane and from aliphatic bifunctional acids, preferably C ₂ -C ₁₂ -Alkyl dicarboxylic acids, such as and, preferably, succinic acid, adipic acid, and / or optionally aromatic bifunctional acids such as, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher-functional acids such as, for example, trimellitic acid or
• D) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 carbon atoms, for example hydroxybutyric acid, hydroxyvaleric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of C and D, the aromatic acids making up no more than 50% by weight, based on all acids;

• E) from the reaction product of C and / or D with aliphatic and / or cycloaliphatic bifunctional and additionally, if appropriate, higher-functional isocyanates, preferably with 1 to 12 C atoms or 5 to 8 C atoms in the case of cycloaliphatic isocyanates, for. B. tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, optionally additionally with linear and / or branched and / or cycloaliphatic bifunctional and / or higher-functional alcohols, preferably C ₃ -C ₁₂ -alkyldi- or -polyols or 5 to 8 carbon atoms in the case of cycloaliphatic alcohols, e.g. B. ethanediol, hexanediol, butanediol, cyclohexanedi methanol, and / or optionally additionally with linear and / or branched and / or cycloaliphatic bifunctional and / or higher functional amines and / or amino alcohols with preferably 2 to 12 carbon atoms in the alkyl chain, for . B. ethylenediamine or aminoethanol, and / or optionally further modified amines or alcohols such as ethylenediaminoethanesulfonic acid, as the free acid or as a salt,

wherein the ester fraction C) and / or D) is at least 75% by weight, based on the sum of C), D) and E);
aliphatic or aliphatic-aromatic polyester carbonates

• F) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ dialcohols such as, for example, ethanediol, butanediol, hexanediol or particularly preferably butanediol and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 to 8 C atoms in the cycloaliphatic ring, such as, for example, cyclohexanedimethanol , and / or partially or completely instead of the diols monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably with C ₂ - C ₁₂ -Alkyldi carboxylic acids, such as neopentyglycol and additionally optionally small amounts of higher functional alcohols such as 1,2,3-propanetriol, trimethylolpropane and aliphatic bifunctional acids such as and preferably succinic acid, adipic acid and / or given As aromatic bifunctional acids such as, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and, if appropriate, small amounts of higher-functional acids such as trimellitic acid or
• G) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 carbon atoms in the alkyl chain, for example hydroxybutyric acid, hydroxyvaleric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of F and G, the aromatic acids making up no more than 50% by weight, based on all acids;

• H) a carbonate component which is produced from aromatic bifunctional phenols, preferably bisphenol-A, and carbonate donors, for example phosgene, or
  a carbonate fraction which is produced from aliphatic carbonic acid esters or their derivatives such as, for example, chlorocarbonic acid esters or aliphatic carboxylic acids or their derivatives such as salts and carbonate donors, for example phosgene, where

the ester fraction F) and / or G) is at least 70% by weight, based on the sum of F), G) and H);
aliphatic or partially aromatic polyester amides

• I) aliphatic bifunctional alcohols, preferably linear C ₂ to C ₁₀ dialcohols such as, for example, ethanediol, butanediol, hexanediol, particularly preferably butanediol, and / or optionally cycloaliphatic bifunctional alcohols, preferably having 5 to 8 C atoms, such as, for example, cyclohexanedimethanol, and / or partially or completely instead of the diols, monomeric or oligomeric polyols based on ethylene glycol, propylene glycol, tetrahydrofuran or copolymers thereof with molecular weights up to 4000, preferably up to 1000, and / or optionally small amounts of branched bifunctional alcohols, preferably C ₃ -C ₁₂ alkyldiols , such as neopentyl glycol and additionally optionally small amounts of higher functional alcohols, preferably C ₃ -C ₁₂ alkyl polyols, such as 1,2,3-propanetriol, trimethylolpropane and aliphatic bifunctional acids, preferably with 2 to 12 carbon atoms in the alkyl chain, such as and preferred Succinic acid, adipic acid and / or optionally aromatic bifunctional acids such as terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid and additionally optionally small amounts of higher functional acids such as trimellitic acid or
• K) from acid- and alcohol-functionalized building blocks, preferably with 2 to 12 carbon atoms in the carbon chain, for example hydroxybutyric acid, hydroxyvaleric acid, lactic acid, or their derivatives, for example ε-caprolactone or dilactide,

or a mixture and / or a copolymer of I) and K), the aromatic acids not making up more than 50% by weight, based on all acids;

• L) an amide fraction from aliphatic and / or cycloaliphatic bifunctional and / or optionally small amounts of branched bifunctional amines, linear aliphatic C ₂ to C ₁₀ diamines are preferred, and additionally optionally small amounts of higher-functionality amines, among the amines preferably hexamethylenediamine, Isophoronediamine and particularly preferably hexamethylene diamine, and from linear and / or cycloaliphatic bifunctional acids, preferably with 2 to 12 carbon atoms in the alkyl chain or C ₅ or C ₆ ring in the case of cycloaliphatic acids, preferably adipic acid, and / or optionally small amounts of branched bifunctional and / or optionally aromatic bifunctional acids such as, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and additionally optionally small amounts of higher-functional acids, preferably having 2 to 10 carbon atoms, or
• M) from an amide portion of acid- and amine-functionalized components, preferably with 4 to 20 carbon atoms in the cycloaliphatic chain, preferably ω-laurolactam, ε-caprolactam, particularly preferably ε-caprolactam,
  or a mixture of L) and M) as the amide portion, the ester portion I) and / or K) being at least 30% by weight, based on the sum of I), K), L) and M), preferably the weight portion 30 to 70% by weight of the ester structures, 70 to 30% by weight of the amide structures,

acts. 5. Film according to claims 1 to 4, characterized in that it is in the Polymers according to the invention are both pure polymers and Mixtures of various of the polymers mentioned can act. 6. Film according to claims 1 to 5, characterized in that it is in the or the biodegradable and compostable polymers around poly ester amide. 7. Film according to claims 1 to 6, characterized in that it is in the inorganic fillers and / or antiblocking agents around aluminum hydroxide, Aluminum silicates (for example kaolin or kaolin clay), aluminum oxides (e.g. Θ-aluminum oxide), aluminum sulfate, ceramics made of silica Aluminum oxides, barium sulfate, natural and synthetic silicas, Layered silicates, silicon dioxide, calcium carbonate of the calcite type, calcium  phosphate, magnesium silicates, magnesium carbonate, magnesium oxide, titanium dioxide, zinc oxide, micro glass balls or mixtures of the sub stamping can act, the mixtures usually the natural Show occurrences (e.g. chalk, talc, etc.). 8. Film according to claims 1 to 7, characterized in that the inorganic fillers are chalk (main proportion: CaCO ₃ , at least 94% by weight). 9. Film according to claims 1 to 8, characterized in that the invention appropriate film from an unfilled polymer and addition of an appropriate Masterbatches filled with inorganic fillers is produced. 10. Film according to claims 1 to 8, characterized in that the Invention appropriate film is made from an appropriately filled compound. 11. Film according to claims 1 to 10, characterized in that the anorga African fillers are distributed in the polymer matrix and a maximum Particle diameter of 60 µm (D 98%) and an average particle diameter have a diameter of less than or equal to 15 µm (D 50%). 12. Film according to claims 1 to 11, characterized in that the inorganic fillers have a maximum particle diameter of 30 µm (D 98%) and an average particle diameter of less than or equal to 6 µm (D 50%) exhibit. 13. A film according to claims 1 to 12, characterized in that the one or more polymers filled with inorganic fillers first by heat and Sheared open, this melt out in one tool wear and cooled until solidification, then with partially crystalline Materials at temperatures above the glass transition temperatures and below the crystallite melting temperature and with amorphous materials  tempered above the glass transition temperatures and then one or stretched several times monoaxially or biaxially and after each Drawings possibly fixed and after these stretching and fixing before gears may need to be surface treated. 14. Film according to claims 1 to 13, characterized in that the biaxial Drawing in the simultaneous stretching process or in the two-stage sequential Process, both elongated first and then laterally as well as first can be stretched laterally and then longitudinally, or in three-step sequential Process whereby both first longitudinal, then transverse and finally longitudinal stretched as well as first crosswise, then lengthways and finally crosswise stretched can be, or in the four-step sequential process, both first lengthwise, then crosswise, then lengthwise and finally stretched as well first stretched lengthways, then lengthways, then lengthways and finally lengthways can, takes place and possibly a fixation to each individual stretching of the film. 15. Film according to claims 1 to 14, characterized in that the biaxial Stretching in the sequential process starting with the longitudinal stretching is carried out. 16. Multi-layer film according to claims 1 to 13, characterized in that the stretch ratio of the monoaxially stretched film in the longitudinal direction 1: 1.5 to 1:10. 17. Multi-layer film according to claims 1 to 13, characterized in that the stretch ratio of the monoaxially stretched film in the longitudinal direction 1: 2.8 to Is 1: 8. 18. Film according to claims 1 to 15, characterized in that the total Longitudinal stretching ratio 1: 1.5 to 1:10 and the total stretching ratio ratio in the transverse direction is 1: 2 to 1:20.   19. Film according to claims 1 to 15, characterized in that the total Longitudinal stretch ratio 1: 2.8 to 1: 8 and the total stretch ratio in the transverse direction is 1: 3.8 to 1:15. 20. Film according to claims 1 to 19, characterized in that the film thickness is less than 500 µm. 21. A film according to claims 1 to 20, characterized in that the film thickness is less than 80 µm. 22. Film according to claims 1 to 21, characterized in that the inventions film according to the invention contains pigments for coloring. It can be act organic or inorganic pigments. 23. A film according to claim 22, characterized in that the pigments are biolo are harmless or have a concentration of less than 1% by weight have d. H. conform to DIN V 54 900. 24. Film according to claims 1 to 23, characterized in that the biological and hydrolytic degradability of the film according to the invention by the Ge holds on inorganic fillers (by buffering acids), the mole kular structure of the biodegradable polymers, the orientation of it inventive film and / or the coating of the film can be controlled can. 25. Use of the film according to claims 1 to 24, characterized in that they are in the form of an opaque, biodegradable and compostable film traded or untreated as well as in printed or unprinted form for packaging in the areas of food or non-food or as an opaque, biodegradable and compostable film in pre-treated or untreated form for greenhouse covers or for lining  of plant growing boxes (e.g. for mushroom cultivation) in the fields Horticulture or agriculture or as opaque, biodegradable and compostable film in pretreated or untreated as well as in be printed or unprinted form for protection and separation functions in the Zu in connection with cosmetics and hygiene articles or as opaque, organic degradable and compostable film in pretreated or untreated Form for surface protection or surface finishing in the area cardboard and paper lamination or as a finished film in pre-treated or untreated as well as in printed or unprinted form and with Adhesive provided can be used as a label or adhesive tape. 26. Use of the film according to claims 1 to 24, characterized in that the film for the production of coated films or composites or Laminates made of the same or different polymers or not with others biodegradable film types is used, the used Coating or adhesives are not necessarily biodegradable and com must be postable. 27. Use of the film according to claim 26, characterized in that all in Composite or laminate or foils used in the coated foil and Coating and adhesives are biodegradable and compostable and thus the composite or the laminate itself is also biodegradable and is compostable. 28. Use of the film according to claims 1 to 24 and 27, thereby ge indicates that from the film according to the invention or the composite or a bag is formed into the laminate, which after decay by the biodegradation process releases its contents. 29. Use of the film according to claims 1 to 24 and 27, thereby ge indicates that the film according to the invention due to its high acid  Permeability to substances, carbon dioxide and water vapor for packaging of fresh fruit and fresh vegetables. 30. Use of the film according to claims 1 to 24 and 27, thereby ge indicates that the film according to the invention or the composite as from material for the manufacture of a packaging or separating or Protective film with very high water vapor permeability serves by this Is pierced with a cold or tempered needle roller.