DE102018108587A1 - Barrier layers and compositions for their preparation - Google Patents

Abstract

For the preparation of a barrier layer on substrates, a composition is proposed which comprises in particular a polymer component, surface-modified platelet-shaped inorganic particles, in particular in the form of metal-, metal oxide- and silicate-based particles, and a proportion of an organic solvent which optionally contains a reactive diluent wherein the particles are modified on their surface with one or more double bond-functional and / or epoxide-functional reactive silane components and with one or more amino-functional components, wherein the particles have a nanoscale platelet thickness, and wherein the polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, Polyesters and cellulose derivatives.

Description

The invention relates to a composition for the preparation of barrier layers, the use of the compositions according to the invention for the preparation of barrier layers, barrier layers made from the compositions according to the invention, substrates provided with a barrier layer and a method for applying a barrier layer to a substrate ,

Packaging and packaging made of various materials are of general importance, both for private and industrial use. In the simplest case, these packages and containers represent only containers.

In particular, when storing valuable, sensitive or dangerous goods they must be protected from environmental influences or generally against external influences. This can be achieved in particular by additional protective layers or barrier layers, which are applied to the respective containers and packaging. An additional protection of valuable and sensitive goods, which often can not be done exclusively by a conventional packaging material, concerns above all a protection against environmental influences such as moisture, oxygen, light and temperature influences.

Especially for materials in the pharmaceutical, semi-luxury, chemical, computer, and construction industries, packaging and containers are used extensively with such additionally applied barrier layers.

As a result of the described aspects, there is an urgent and growing need in industrial societies for barrier coatings for packaging and packaging that are cost effective and easy to apply, which exhibit good adhesion to the common packaging materials and in which the elastic properties and the hardness are adjustable.

However, not only for use on containers and packaging or films, there is an increasing demand for new innovative barrier coatings, but also for the protection of metals from corrosion, especially the barrier properties of the coating or applied conversion layers to oxygen, electrolytes and water are of elementary importance.

As barrier layers, by means of vacuum methods, for example by means of the so-called Physical Vapor Deposition (PVD), deposited metal layers, in particular PVD aluminum layers, have proven useful, which, however, often have to be protected against oxidation and corrosion by applying organic coatings themselves.

The use of PVD-coated films as packaging and for the protection of sensitive goods from oxygen and water vapor is widely known. The barrier effect of a vapor deposited thin metallic layer is very high.

Disadvantages, however, are the complex and expensive production processes in a high vacuum and the sometimes pronounced susceptibility of these layers to corrosion processes. Therefore, alternative barrier layers have already been recommended in the prior art for a number of applications.

In the CN 2015 76687 U For example, fluorine component-free films consisting of a base layer, an aluminum-metal interlayer, and a protective layer having a high barrier to water vapor and other environmental factors are described for enhancing weatherability of photovoltaic cells.

Coated aluminum foils are also used in the JP 2001 006631 A1 described as excellent gas and electrolyte barrier layers.

The US 4,601,943 A also describes aluminum foils which have vapor barrier properties arranged between two plastic films and can thus be used as fire protection.

In the DE 101 52 266 C1 Coated water-soluble hollow bodies are described using water-soluble polymers with a vapor-deposited, by means of chemical vapor deposition (CVD), applied coating of graphite, titanium and chromium nitride and carbonitride.

The WO 2008/034733 A1 ( EP 2 069 210 B1 describes packaging containers with barrier layers of single or multi-layer arrangements including metal foils and metal layers, for example of aluminum, which are optionally combined with different layers of plastics, also in the form of composite films, the metal layers preferably using PVD methods on the Containers are applied. This multilayer arrangement may alternatively be obtained by a so-called multi-component injection molding.

Barrier layers consisting of organic film formers such as polyvinylidene chloride (PVDC) or ethylene-vinyl alcohol copolymers (EVOH) are also in use. However, the barrier effect of these polymer layers is not sufficiently high for most applications involving an oxygen barrier, and especially a water barrier. For the most part, these barrier layers are therefore combined with other metallic or oxidic barrier layers.

To improve the barrier effect, so-called hybrid materials have also been used. In the DE 196 50 286 A1 Inorganic-organic hybrid materials (ORMOCER layers) are described by way of example which show barrier properties, in particular on a support material already pre-coated with SiO _x . Experience has shown that these hybrid coatings for application are particularly well on polar, hydroxyl-containing and metallic surfaces, while on non-polar, eg polyolefinic surfaces, especially in flexible and / or elastic substrates (eg films, in particular packaging films), due to their hardness, brittleness or Lack of elasticity can not be used to produce a permanent barrier effect.

To achieve maximum effect in these hybrid material layers, therefore, a two-layer structure of a metallic or oxidic layer and a layer of the hybrid material is often necessary.

In the WO 01/66654 A1 and the WO 01/66655 A1 describes mixtures of condensation products of bis-aminomethoxysilane or other aminosilanes and phenolic compounds in methanol for the preparation of barrier layers.

In the WO 01/66656 A2 and the WO 01/66662 A2 For example, mixtures of bis-aminotrimethoxysilane and aminoethylaminopropyltrimethoxysilane with multifunctional acrylates and ethylenically unsaturated organic acids are described as UV-curable barrier layers.

The DE 103 50 125 A1 describes barrier layers for organosilane-based gases which comprise at least one organoalkoxysilane whose organo-functionality has at least one unsaturated hydrocarbon group, at least one aminoalkylalkoxysilane, at least one polyol and at least one co-condensate of said components. These barrier layers can be used to advantage in base-insensitive substrates such as polyolefins. Experience has shown, however, that certain substrate damage can occur, especially with thinner substrates made of polyesters or with a metal substrate due to the water content and, above all, due to the relatively high content of the coating composition of amino-functional silanes. This is especially true for surface-modified, thin platelet-shaped metal particles due to the basic corrosive properties of this matrix material when such particles are used in such coating compositions.

However, the most important properties of barrier layers besides the barrier effect against the respective environmental influences are, above all, the robustness, flexibility and costs in the application process as well as the permanence of these coatings.

An essential role for the requirements of a barrier layer is played by the immense quantities of packaging and packaging produced in the industrialized nations as well as the worldwide pressure to reduce costs and increase productivity.

As already explained, according to the prior art, metal layers, mostly aluminum metal layers, are applied under vacuum by means of PVD methods as barrier layers to a very wide variety of materials. These processes are on the one hand energy and cost intensive and on the other hand by the use of a vacuum process also not very flexible.

The above-mentioned aspects of the universal applicability and adhesion to different substrates, the cost-effective and simple application, the control of the hardness and the elastic properties can best be accommodated by an organic coating.

However, it has been found that even highly crosslinked two-component (2K) clearcoat materials alone can not provide a sufficient barrier to gases.

There is therefore a need for barrier layers which can be applied more simply and inexpensively, while still being able to produce a barrier effect, for example to oxygen and water vapor, of a similar order of magnitude as can be achieved with the barrier effect of a PVD layer of metal.

The object of the present invention is to propose a composition with which barrier layers or barrier coatings can be produced more cost-effectively, even for large quantities.

This object is achieved by compositions having the features of claim 1.

The composition according to the invention for a barrier layer can be applied in a cost, time and energy-efficient manner, in particular using conventional and generally accessible painting installations, by dipping or by printing, in contrast to the described PVD methods in the prior art.

This also applies to substrates in the form of films in which the compositions according to the invention can be applied in particular by means of doctor blades or a printer as a layer.

In addition, production-related disadvantages of barrier coatings consisting of PVD metal layers are avoided by the present invention. The time-consuming, energy-consuming and ultimately cost-intensive metal coating process in the established state of the art is replaced according to the present invention by an application of a liquid composition of coating components.

According to the invention, the composition comprises a polymer component, surface-modified platelet-shaped inorganic particles, in particular in the form of metal, metal oxide and silicate-based particles, and a portion of an organic solvent which optionally comprises a reactive diluent. The particles are modified on their surface with one or more double bond-functionally reactive silane components and with one or more amino-functional components, the particles having a nanoscale platelet thickness. The polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, polyesters and cellulose derivatives.

In the context of the present invention, the term particles with "nanoscale platelet thickness" particularly includes platelet-shaped particles having an average thickness of about 200 nm or less, in particular about 100 nm or less, more preferably about 80 nm or less, and optionally about 60 nm or less.

The average thickness of the platelet-shaped particles can be determined manually by means of electron microscopy images.

The platelet-shaped metal-based particles, in particular aluminum particles, containing barrier coatings according to the invention are not only suitable as a barrier coating for protection against gases and moisture, but also offer protection against thermal radiation and UV light in particular.

In the case of cellulose derivatives in particular partially esterified cellulose derivatives are preferred, wherein the degree of esterification is preferably about 1 to about 5 mol%, for example about 2 mol%.

The nanoscale platelet-shaped inorganic particles are preferably selected from metal, oxide and nitrogen-containing platelet-shaped particles. In particular, the particles are selected from platelet-shaped aluminum and aluminum oxide particles, platelet-shaped glass particles, platelet-shaped aluminum silicate and silicate particles and also platelet-shaped boron nitride particles.

To increase the barrier properties, it is also possible to add platelet-shaped fillers, such as talc or mica materials. It turns out, however, that due to the hydrophilicity of these oxidic inorganic platelets and the water storage capacity of the coating is greatly increased, so that the use of these materials is subject to certain restrictions. Furthermore, these materials are more effective if they are compatible with the coating matrix and further preferably chemically crosslinkable with the binder matrix.

According to the invention, this problem is also solved by the composition according to the invention which comprises surface-modified platelet-shaped inorganic particles, in particular metal and silicate particles, with amino-functional components and olefinically double bond-functional reactive silane components.

Preferably, the platelet-shaped particles are additionally modified with one or more reactive epoxide-functional silane components.

The optional epoxide functional component is preferably a 3-glycidyloxypropyltrimethoxysilane.

The amino-functional component for surface modification of the platelet-shaped particles is in particular selected from polyfunctional low molecular weight aliphatic, aromatic and heterocyclic components and amino-functional polyether components, 2-aminoethyl-3-amino-propyltrimethoxysilane and 3-aminopropyltrimethoxysilane or mixtures thereof.

The double bond-functionally reactive silane component for surface modification of the platelet-shaped particles is preferably selected from the components vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane or mixtures thereof.

The multifunctional low molecular weight aliphatic, aromatic or heterocyclic components typically have a molecular weight of about 600 g / mol or less, in particular of about 500 g / mol or less.

Typically, the molecular weight is about 40 g / mol or more, although components with lower molecular weights can also be used according to the invention.

The concentration of these surface-modified platelet-shaped particles according to the invention in the barrier coating is in particular about 0.1 to about 60% by weight, preferably about 1 to about 40% by weight and further preferably about 1 to about 30% by weight. -%, Based on the solids (FK) of the polymer component used as a binder. This is especially true when the oxygen barrier property of the barrier coating to be produced is in the foreground.

However, high concentrations of platelet-shaped aluminum particles result in a marked decrease in the transparency of the coatings, which is undesirable in a wide range of applications. Even with purely UV-curing designed compositions, high proportions of aluminum particles are not favorable for hardening the barrier coating or its polymer component over the entire thickness of the coating and for achieving uniform properties.

Here, the use of mixtures of platelet-shaped particles, which in addition to the aluminum particles also comprise other particles, in particular silicate particles, is recommended. The content of aluminum particles in such cases is preferably limited to about 10% by weight or less.

If the transparency of the coating is of secondary importance, higher aluminum particle contents can also be used, in which case either additional or exclusive thermal curing of the polymer component is adjusted and adapted accordingly.

If, above all, a barrier effect towards the permeation of water and steam is desired, the composition according to the invention preferably comprises about 30% by weight to about 60% by weight, more preferably about 50% by weight to about 58% by weight. -% of surface-modified nanoscale particles, in particular aluminum particles, based on the solids content of the polymer component.

In both cases, the surface-modified platelet-shaped particles according to the invention preferably have an average platelet thickness of from about 10 to about 200 nm, in particular from about 20 to about 100 nm and particularly preferably from about 20 to about 80 nm.

It has been found that in the case of the inventive solvent- and reactive-diluent-based barrier coatings, the strong crosslinking, which is important for the barrier property, can be formed above all by chemical bonds. As will be shown in the following Examples 1 to 3, it is obvious that, in particular, particles which have an olefinic double bond and / or an epoxidic functionality due to their surface modification greatly promote cross-linking in the solvent- and reactive-diluent-based barrier layers according to the invention and thus the barrier properties.

The solvent-based and reactive-diluent-based barrier layer compositions according to the invention therefore preferably contain surface-modified nanoscale platelet-shaped particles and, in particular, surface-modified nanoscale platelet-shaped metal particles with olefinically double bond-functional silanes and optionally additionally with epoxide-functional silanes, where the double-bond-functional reactive silane component is used for surface modification of the platelet particles. shaped particles in turn is preferably selected from the components vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane or mixtures thereof.

For the solvent and / or reactive diluent-containing compositions of the present invention, which are more nonpolar, more hydrophobic polymer components, e.g. modified and esterified celluloses, polyurethanes, polyacrylates, polyvinyl acetates and polyesters, it has been found that surface-modified platelet-shaped particles are preferred which have surface modifications with high proportions of double-bond and / or epoxide-functional silanes. These components are deposited on the surface of a platelet-shaped particle, in particular a platelet-shaped metal and furthermore preferably aluminum particle, and are first chemically crosslinked by post-heating.

By adding a free radical initiator, it is optionally possible to carry out additional free-radical crosslinking of the olefinic double bond-functional silane components, so that the metal flakes are enveloped by a densely crosslinked hybrid layer of silane and organic components. This layer surrounding the metal platelets hinders the incorporation of water on the platelet surface and protects the metal platelets from corrosion and in particular oxidation.

For radically, in particular for UV-curing and reactive diluent-containing compositions, it may also be advantageous if only a thermal curing of the particle surface modification is carried out to subsequently enable a radical crosslinking of the double bond function of the barrier particles in the UV-curing polymer network ,

The solvent-containing and reactive diluent-containing compositions according to the invention comprise surface-modified platelet-shaped metal-particle and / or platelet-shaped oxidic inorganic particles with olefinically double-bond-functional silanes and / or with epoxide-functional silanes.

The barrier layers ultimately obtained from the compositions according to the invention preferably have a dry layer thickness of about 0.1 μm to about 20 μm, in particular of about 0.5 μm to about 10 μm and more preferably of about 0.5 μm to about 5 μm and in particular have a layer with amino- and double bond-functionally surface-modified platelet-shaped particles embedded in a preferably thermoset polymer matrix.

In the context of the present invention, dry film thickness is understood as meaning the layer thickness of a coating according to the invention after it has cured, as measured DIN EN ISO 139 (at a temperature of 23 ° C and a relative humidity RH of 50%) by means of the eddy current method according to DIN EN ISO 2808: 2004 ; by fixing the substrate on a suitable metal support without and with the surface-applied barrier coating. The difference of the values obtained then represents the dry layer thickness of the barrier coating.

In a further embodiment, a barrier layer according to the invention may be overcoated with one or more optionally thicker, particle-free, optionally also thermosetting coatings. This embodiment of a barrier coating is particularly suitable for preventing the permeation of water, wherein the barrier coating for this application preferably with a superficial coating with a layer thickness of about 4 .mu.m to about 60 .mu.m, in particular from about 10 .mu.m to about 40 .mu.m , more preferably from about 15 microns to about 25 microns, a particular particle-free varnish layer is provided, wherein the underlying layer according to the invention (barrier layer) is preferably about 0.5 microns to about 3 microns, in particular about 0.7 microns to about 1 micron thick, nanoscale thick platelet-shaped particles, in particular aluminum particles contains.

The underlying layer (barrier layer according to the invention) for preventing the permeation of water preferably contains about 30% by weight to about 60% by weight, more preferably about 50% by weight to about 58% by weight, of the present invention Surface-modified nanoscale thick platelet-shaped particles, based on the solids content of the binder.

Further preferably, the barrier coating according to the invention is colorless, dark or white formulated and has no metallic effects. This can be achieved by the additional use of white or black pigments, in which case the barrier coating can be formulated substantially neutral in color, dark or white, and further preferably has no visually striking metallic effects.

In principle, the barrier coating according to the invention can be used on different substrates, the application to plastic materials for packaging and containers being preferred.

The composition according to the invention can be used for the production of barrier layers on substrates of all kinds. In particular, it is used for the production of barrier coatings on metal, paper, cardboard and plastic substrates of all kinds and combinations thereof, in particular for the production of barrier coatings on plastic packaging and moldings of all kinds, furthermore preferably on plastic cartridges and plastic capsules, plastic films and plastic bottles consisting of polyamide (PA), polyethylenes (HDPE, LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyacrylates (especially polymethyl methacrylate PMMA), polyesters (especially polyethylene terephthalate PET), polylactides (PLA) and polycarbonate (PC).

But it can also be used for corrosive protection of metal substrates such as aluminum alloys, steels or other ferrous materials.

Optionally, the barrier layer according to the invention is overcoated with a thicker, relatively highly crosslinked thermoset organic, metal-particle-free coating or is part of a multilayer coating which is used, for example, in industrial and automotive coatings.

It may also be applied to other metal and plastic surfaces as part of a multi-coat application and / or a multiple coating, and further preferably it is applied to two opposite sides of a substrate, such as on inner and outer sides of moldings or films.

The use according to the invention furthermore comprises applications in which at least one barrier layer of a multilayer structure having a plurality of different layers and / or a multilayer structure having a plurality of identical layers is produced from the composition, preferably on metal or plastic surfaces and more preferably on two opposite sides, for example on the inside - and outsides of moldings or films.

The invention further relates to a substrate coated with a barrier layer, in particular in the form of a shaped body, a hollow body, a planar substrate or a foil with an inner and / or outer barrier layer.

• - Bereitstellen einer erfindungsgemäßen Zusammensetzung wie zuvor beschrieben; und
• - Auftragen der Zusammensetzung auf die Substratoberfläche mittels Rakeln oder Druckverfahren;

wobei das Substrat vorzugsweise eine Folie, insbesondere eine Verpackungsfolie ist.Finally, the invention relates to a method for applying a barrier layer on a substrate, the method comprising the steps:

• Providing a composition according to the invention as described above; and
• Applying the composition to the substrate surface by means of doctoring or printing processes;

wherein the substrate is preferably a film, in particular a packaging film.

• 1 zeigt die Gewichtszunahmen bei unterschiedlich mit der Barrierebeschichtung beschichteten Probekörpern P2 (ohne Klarlackschicht KL) und P3 (+ 20 µm KL) gegenüber der nicht beschichteten Referenzprobe P1;
• 2 zeigt im Vergleich die Gewichtszunahmen bei nicht beschichtetem Probekörper und den mit den jeweils mit 2,5 µm dicken Barriereschichten und mit einer unterschiedlich dicken Klarlackschicht (KL) überlackierten Probekörpern P4, P5 und P6;
• 3 zeigt im Vergleich die Gewichtszunahmen bei der nicht beschichteten Referenzprobe P1 und des nur mit Klarlack (KL) beschichteten Probekörpers P8 gegenüber dem Probekörper P7 mit einer 0,8 µm dünnen erfindungsgemäßen Barriereschicht und einer darauf applizierten Klarlackschicht (KL);
• 4 zeigt im Vergleich die Gewichtszunahmen bei der nicht beschichteten Referenzprobe P1 und bei mit erfindungsgemäßen Barriereschichten beschichteten Probekörpern P9, P10 und P11, wobei die Barriereschichten 2,5 µm dick sind und unterschiedlich oberflächenmodifizierte Aluminium-Partikel enthalten;
• 5 zeigt das Transmissionsspektrum von wässrigen Bromphenolrot-Lösungen in Abhängigkeit des pH-Wertes;
• 6 zeigt im Vergleich die Sauerstoffbarrierewirkung (in Form von auf 10 µm Schichtdicke bezogenen OTR-Werten) von mit UV-Barriere-Referenz-Beschichtungen (P16 - ohne Partikel, P17 - nicht modifizierte Partikel) und mit erfindungsgemäßen UV-Barriereschichten beschichteten LDPE Folien, wobei die erfindungsgemäßen UV-Barriereschichten einen Gehalt von 1,2 Gew.-% Aluminium-Partikel mit einer mittlerer Plättchendicke von 50 µm und zusätzlich Isocyanate als Härterkomponente enthalten (P18, P19, P20); und
• 7 zeigt im Vergleich die Sauerstoffbarrierewirkung (in Form von auf 10 µm Schichtdicke bezogene OTR-Werte) einer mit einer UV-Barriere-Referenz-Beschichtung (P16 - ohne Partikel) und den mit erfindungsgemäßen UV-Barriereschichten beschichteten LDPE Folien (hier ohne Zugabe von Isocyanat-Härter) mit einem Metallpartikelgehalt von 0,3 Gew.-% (P21) und teilweise zusätzlich mit einem Gehalt von 0,8 Gew.-% (P22) bzw. 1,6 Gew.-% (P23) an nichtmetallischen nanoskalig dicken Silikat-Partikeln (Talkum, Plättchendicke ca. 80 nm).

These and other advantages of the invention will be described in more detail below with reference to the examples and figures.

• 1 shows the weight increases in differently coated with the barrier coating specimens P2 (without clearcoat KL) and P3 (+ 20 μm KL) compared to the uncoated reference sample P1 ;
• 2 shows in comparison the weight increases in uncoated specimen and with each with 2.5 micron thick barrier layers and with a different thickness clearcoat (KL) overcoated specimens P4 . P5 and P6 ;
• 3 shows in comparison the weight increases in the uncoated reference sample P1 and the clearcoat (KL) coated specimen P8 opposite the test piece P7 with a 0.8 μm thin barrier layer according to the invention and a clearcoat layer (KL) applied thereto;
• 4 shows in comparison the weight increases in the uncoated reference sample P1 and in coated with barrier layers according to the invention test specimens P9 . P10 and P11 wherein the barrier layers are 2.5 μm thick and contain different surface-modified aluminum particles;
• 5 shows the transmission spectrum of aqueous bromophenol red solutions as a function of the pH value;
• 6 shows in comparison the oxygen barrier effect (in the form of OTR values related to 10 μm layer thickness) of UV barrier reference coatings (US Pat. P16 - without particles, P17 - Unmodified particles) and with UV barrier layers coated according to the invention LDPE films, wherein the UV barrier layers according to the invention contain a content of 1.2 wt .-% aluminum particles having an average platelet thickness of 50 microns and in addition isocyanates as a hardener component (P18, P19, P20); and
• 7 shows in comparison the oxygen barrier effect (in the form of OTR values related to 10 μm layer thickness) of one with a UV barrier reference coating ( P16 without particles) and the LDPE films coated with UV barrier layers according to the invention (here without addition of isocyanate hardener) with a metal particle content of 0.3% by weight ( P21 ) and in some cases additionally with a content of 0.8% by weight ( P22 ) or 1.6% by weight ( P23 ) of non-metallic nanoscale silicate particles (talc, platelet thickness about 80 nm).

EXAMPLE 1 Performance of the Surface Modifications of Aluminum Particles According to the Invention for Use in Compositions Containing Solvents and Reactive Diluents

A polyetheramine (Jeffamine® D400 from Huntsman Corp.) is dissolved in 225 g of butyl acetate (BuAc) to give a content of 4.0% by weight of solids (FK) of polyetheramine, based on the mass of the particles. With stirring at 800 rpm on the dissolver (Getzmann) are within 5 min 60 g of a solvent-containing about 10 wt .-% paste of nanoscale thick platelet-shaped aluminum particles (Decomet 1008/10, Fa. Schlenk Metallic Pigments GmbH), so that an approximately 2.5 wt .-% particle dispersion is formed. The particles have an average thickness of about 50 nm.

Thereafter, the particle dispersion is homogenized for 20 min at room temperature while maintaining the stirring speed. Vinyltrimethoxysilane (VTMO) is slowly added dropwise to a content of 8.0% by weight of VTMO. Likewise, a further reactive olefinically double bond-functional silane component A is attained to a content of Y% by weight, and optionally a further reactive epoxide-functional silane component B to whose content Z% by weight is added dropwise. The mixture is then stirred for 5 minutes and finally heated to 70 ° C. The above percentages by weight are in each case based on the mass of the particles (solids FK) in the dispersion.

After reaching the temperature of 70 ° C is slowly azo-bis-isobutylonitrile AIBN dissolved in butyl acetate (5 wt .-% solution) is added dropwise until a proportion of 1.6 wt .-% AIBN based on the weight fraction of the particle or particles becomes. To crosslink the VTMO and the reactive silane component A and optionally the silane component B, the temperature is maintained at 70 ° C. for 30 minutes with stirring.

The particle dispersion is cooled with stirring to room temperature, centrifuged and then the particle content is adjusted by the addition of butyl acetate again to about 10 wt .-%. Thus, the composition is in the form of a paste.

The nanoscale platelet-shaped aluminum particle pastes obtained by the described particle modification process are subsequently used for the barrier coatings according to the invention.

In Table 1 below, the compositions are surface modifications M1 . M2 . M3 for the differently surface-modified particles used in the barrier coatings. Table 1 Formulations M1, M2, M3 for surface modification of particles modifying component M1 M2 M3 Jeffamine D400 [% by weight / FK particles] 4.0 4.0 4.0 Vinyltrimethoxysilane VTMO [wt% / FK Particles] 8.0 8.0 8.0 Azo-bis-isobutylonitrile AIBN [wt% / FK Particles] 1.6 1.6 1.6 Olefin-functional silane component A: MEMO (3-methacryloxypropyltrimethoxysilane), [Y% by weight / FK particle] 0.0 8.0 0.0 epoxide-functional silane component B: GLYMO (3-glycidyloxypropyltrimethoxysilane) [Z% by weight / FK particles] 0.0 0.0 8.0

Example 2: Barrier effect of the barrier coating according to the invention against the absorption of water

In order to achieve a high barrier effect when the samples are loaded by or with aqueous media, it has proven advantageous to use barrier coatings having the highest possible content of metal barrier particles. The sole use of oxidic barrier particles is less preferred in this case due to the increased water storage capacity of these particles. However, the oxide particles can be added in smaller amounts to metal particles mixed advantageous since they affect the transparency of the coating less and are less expensive. Thus, by incorporating silicate particles (e.g., talcum particles), it is often possible to save a corresponding amount of more expensive aluminum particles without appreciably altering the barrier properties of the coating.

The compositions for the preparation of the barrier layers according to the invention were in turn formulated with a content of 55% by weight barrier particles of aluminum and a solvent-based binder system.

Polyethylene specimens (sealable cartridges, see below) were dipped three times using a composition of the invention having the particulate sample modified M1 from Example 1, Table 1, coated. The coatings obtained after three dipcoating a total layer thickness of about 2.5 microns. The composition according to the invention for producing the barrier layer was composed as shown in Table 2: Composition for the production of the barrier layer according to the invention, with about 20% by volume or about 55% by weight of nanoscale and platelet-shaped aluminum particles components Composition according to the invention [g] Binder component CAB 381 - (20% strength by weight in butyl acetate) 1.50 butyl 46,00 methoxypropylacetate 46,80 Aluminum particle component M1 (10% by weight in butyl acetate) 5.00 Metatin 812 ES (DBTL) 0.10 Hardener component Desmodur N 3600 0.60

The binder component CAB 381 is a cellulose acetate butyrate (manufacturer: Eastman).

Dibutyltin (Metatin 812 ES, manufacturer: DOW Chemicals) is used as a catalyst for the curing reaction.

Desmodur N 3600, an aliphatic polyisocyanate (manufactured by Covestro), is used as a curing component in the formulation.

In addition, a commercially available two-component (2K) clearcoat material (2K-HS Clearcoat CC4, MIPA Co.) was applied to some of the test specimens by spraying to achieve a dry film thickness of 20 to 30 μm.

For both coatings, a solvent-based formulation was used. The coated specimens were subsequently cured in a circulating air oven at 70 ° C. for 30 minutes and conditioned for at least 48 hours in a climatic chamber (at 23 ° C., 60% rh). For the characterization of the water and water vapor permeability, closable polyethylene cartridges having a length of about 32 cm and a diameter of about 5 cm and a weight of about 46 g were used as test specimens.

The water absorption by the barrier coating was characterized by a water immersion test in which the specimens filled with in each case 65 g of phosphorus pentoxide were immersed for a total of 600 hours in 30 ° C tempered water. The water absorption of the test specimens with and without barrier coating as well as the test specimen with a barrier coating and an optional additional clearcoat were followed gravimetrically and evaluated.

In 1 For example, the mass increases obtained in the water immersion test are a function of time for the uncoated reference sample P1 compared to the differently coated samples P2 and P3 shown.

For the samples P2 and P3 In the dip coating, a composition according to Table 2 was used. In the sample P3 was additionally applied a clearcoat (KL), so that a dry film thickness of about 20 microns is obtained.

It can be seen that the uncoated reference sample P1 shows a relatively high water absorption, while the coated with the barrier layer according to the invention and the clear coat specimen ( P3 ) has no measurable water absorption.

For the coated only with the barrier layer according to the invention specimens P2 On the other hand, a medium water absorption in the water immersion test was found in comparison to both extremes. Furthermore, in the case of the test body coated only with the barrier layer P2 , in contrast to the additionally coated with clear coating specimen P3 , partially Enthaftungserscheinungen be noted, but only after about 600 h.

From the in 2 It can be concluded that a clearcoat layer of about 20 .mu.m dry layer thickness, coated onto the barrier layer according to the invention, is advantageous for achieving a good water barrier effect for a large number of applications, while the barrier effect with respect to water is obtained with a significantly greater layer thickness of the clearcoat layer can even worsen.

In order to allow a clear and meaningful differentiation between the samples, the tests in the two-layer structure (barrier layer and clearcoat layer) were further carried out at a clearcoat film thickness of 40 microns.

Out 3 It can be seen that even a very thin barrier layer of the invention with a layer thickness of about 0.8 microns (Porbekörper P7 ) extremely advantageous in terms of water-barrier property compared to a sole 40 micron thick clearcoat film impact (specimens P8 ).

In summary, it can be stated that the use of a barrier layer, prepared from a composition according to the invention, and an additional clearcoat layer, for a longer period of time, can achieve a strong barrier to water absorption even when the test specimens are submerged in water. Further, the coating of the additionally clear-coated specimen showed excellent resistance to water and excellent wet adhesion.

Example 3: Barrier effect of the barrier layer according to the invention against vapors and gases

In the following Table 3, the composition of the present invention using modified aluminum particles is as a formulation 1 listed. The reference formulation 1 represents the barrier layer formulation 1 with non-surface-modified aluminum particles M0 which, apart from the much thinner dry film thickness (effect coating with basecoat film thickness according to the prior art approx. 15 μm-20 μm), corresponds to conventional effect pigment coatings. The reference formulation 2 represents the state of the art from the DE 103 50 125 A1 . WO 01/66654 A1 and the WO 01/66655 A1 is known. This formulation is characterized by the addition of different silane components to the organic binder and by formation of so-called hybrid layers. Composition according to the invention with modified aluminum particles (formulation 1), reference formulation 1, which corresponds to effect pigment coatings, and reference formulation 2 according to the prior art components Formulation 1 according to the invention [g] Reference Formulation 1 [g] Reference Formulation 2 [g] Binder component CAB 381 (20% strength by weight in butyl acetate) 1.50 1.50 1.50 butyl 46,00 46,00 46,00 MPA 45,40 45,40 45,40 Aluminum particles modification M0 each as a 10 wt .-% paste 0.00 5.00 5.00 M1, M2, M3 each as 10 wt .-% iqe paste 5.00 0.00 0.00 Metatin 812 ES (DBTL) 0.10 0.10 0.10 VTMO 0.00 0.00 0.02 Hardener component Desmodur N 3600 0.60 0.60 0.60 MPA 1.40 1.40 1.40

In order to achieve a high barrier effect when the samples are loaded by or with aqueous media, it has proven advantageous to use barrier layers with a high content of metal barrier particles. Oxide barrier particles are less suitable in this case because of the increased water storage capacity.

The barrier layers obtained from these solvent-based compositions (binder systems) each have a content of about 55% by weight of barrier particles of aluminum.

Barrier effect of the barrier layer according to the invention with respect to water vapor

The barrier effect of the barrier layer according to the invention against gases such as water vapor was investigated by testing the test bodies (polyethylene cartridges) filled with 65 g of phosphorus pentoxide by means of a condensation water test based on DIN EN ISO 6270 loaded and the weight gain of the cartridges was determined by water absorption.

The graphic in 4 shows a comparison of the weight gains of the uncoated specimen P1 and the specimen P9 . P10 and P11 , which were coated with a 2.5 micron thick barrier layer according to the invention, which contained different surface-modified aluminum pigments, under load of the samples in the condensation test based on DIN EN ISO 6270 depending on the load duration.

The results in 4 show that the formulations of the barrier layers according to the invention, which contain the aluminum particles, which, using an amino-functional low molecular weight polyether (Jeffamine) and exclusively with a double bond-functional silane component VTMO (Specimen P9 ; modification M1 ) or additionally with MEMO (test specimen P10 ; modification M2 ), a significantly increased water vapor barrier in comparison to the uncoated test specimens (US Pat. P1 ) exhibit.

The test specimens which were modified both using an amino-functional low molecular weight polyether (Jeffamine) and with the double bond-functional silane component VTMO and also with GLYMO (test specimens) P11 ; modification M3 ), showed a slightly lower barrier to water vapor, especially during prolonged exposure.

Barrier effect of the barrier layer according to the invention against carbon dioxide gas CO ₂

The barrier effect against gases such as carbon dioxide was determined in practice by first producing a hydrogen carbonate / carbon dioxide buffer based on a natural, carbonated mineral water (Eltina Sprudel, Eberstädter Mineralbrunnen).

In order to achieve a high barrier effect when the samples are loaded by or with aqueous media, it has proven advantageous to use barrier layers with a high content of barrier particles of metals. Oxide barrier particles are also less in this case due to their increased water storage capacity. These barrier layers contain about 5% by weight barrier particles of aluminum.

To prepare the bicarbonate / carbonic acid buffer, 765 mg of sodium bicarbonate were first dissolved in 1.5 liters of distilled water and subsequently adjusted to a pH of 6.1 by adding a strongly diluted hydrochloric acid. As an indicator, 6 mg bromophenol red pH indicator (CAS: 102185-50-2) were added to this solution.

In order to test the CO ₂ barrier property, 250 g of this buffer solution were now each made into uniform, approximately 15 cm long closable test specimens of polyethylene terephthalate PET (weight about 5 g) with a wall thickness of about 80 μm and a diameter of about 4 cm filled and gas-tight with a corresponding lid made of the same material.

During a 288 h (24 days) shaking load with 2 strokes per sec., A continuous diffusion of the present gaseous carbon dioxide through the wall of the test specimens takes place, resulting in a pH change of the aqueous indicator solution inside the vessels and colorimetrically, monitored and quantified using a UV-Vis spectrometer.

The 5 shows that a transmission difference ΔT between 577 nm and 660 nm correlates with the different pH values and, in the case of the carbonate / carbonic acid buffer system, with the contents of carbon dioxide in the gas-tight test specimens.

If the transmission differences are determined analogously for the differently coated test specimens after a 288 h shaking load, then very different values are obtained, as shown in Table 4. Table 4 Transmission differences ΔT of differently coated PET specimens after a 288 h shaking load Samples name Delta T value PET test specimen without coating (P0) 18.5 PET test specimen with reference formulation 1 (P12) 15.9 PET test specimen with reference formulation 2 (P13) 16.8 PET specimen + formulation with aluminum particles M1 (P14) 14.1 PET specimen + formulation with aluminum particle M2 (P15) 14.4 PET specimen + formulation with aluminum particle M3 (P16) 15.2

Looking at the results in Table 4, the following ranking for increasing the CO ₂ barrier for the solvent-based barrier layer compositions (Table 3) containing the differently modified aluminum particles can now be seen M1 . M2 . M3 (Table 1):

Reference 0 (P0) <Reference 2 (P13) <Reference 1 (P12) <with aluminum particle M3 (P16) <with aluminum particle M2 (P15) ≅ with aluminum particle M1 (P14)

From the above ranking of the various solvent-based barrier layers, it can now be clearly seen that the formulations containing the aluminum particles, which were modified using an amino-functional low molecular weight polyether (Jeffamine) and a double bond-functional silane component VTMO and / or MEMO, significantly increased CO ₂ gas barrier compared to the corresponding reference formulations, which contain the non-additionally modified aluminum particles ( P12 ; Reference formulation 1 ) and / or which additionally contain the corresponding double-bond-functional silane component VTMO (at the corresponding concentration) as direct addition in the formulation (P13, reference formulation 2 ).

The test specimens modified using both an amino-functional low molecular weight polyether (Jeffamine) and the double bond-functional silane component VTMO and GLYMO ( P16 ; modification M3 ), showed over the barrier coatings with the modified aluminum particles with M1 or M2 ( P14 respectively. P15 ) has a somewhat attenuated barrier to CO ₂ . The uncoated specimen ( P0 ) exhibited the weakest gas barrier effect.

Barrier effect of a erfindunasaemäßen reactive diluent-containing UV-curing coating over oxygen

To achieve a high barrier effect in reactive diluent-containing formulations according to the invention, it has proved to be advantageous to use metal barrier particles. The disadvantage, however, is that although the metal particles increase the barrier action towards gases such as oxygen, they at the same time greatly reduce the UV transparency of the composition necessary for UV curing of the coating. This leads to layers which have a reduced degree of crosslinking, which in turn has a negative effect on the compactness of the layer and thus on the barrier effect itself as a result of a lower density of the polymer network.

• Variante 1: Es wird eine Konzentration von Plättchen-förmigen Metallpartikeln von beispielsweise 1,2 Gew.-% in der aus Bindemittel, Härter, Reaktivverdünner und Initiator gebildeten Barriereschicht, gewählt. Hieraus resultieren eher metallische und relativ intransparente Barriereschichten. Um eine ausreichende Vernetzung der Barriereschicht trotz der geringen Transparenz zu erzielen, wird der erfindungsgemäßen Zusammensetzung zusätzlich eine thermische Härterkomponente zugegeben, z.B. in Form von Isocyanaten, die die Behinderung der Vernetzung durch die das UV-Licht reflektierenden Metallplättchen kompensieren kann.
• Variante 2: Es wird eine Konzentration von Plättchen-förmigen Metallpartikeln von beispielsweise 0,4 Gew.-%, in der aus Bindemittel, Härter, Reaktivverdünner und Initiator gebildeten Barriereschicht gewählt. Hieraus resultieren trotz des Gehalts an metallischen Partikeln semi-transparente Barriereschichten, so dass die UV-Härtung mit dem Ergebnis einer stärkeren Vernetzung durchgeführt werden kann. Damit können auch ohne die Verwendung zusätzlicher Härterkomponenten bessere Barriereeigenschaften erzielt werden. Die Barrierewirkung der Beschichtung wird bei diesem erfindungsgemäßen Ansatz zusätzlich durch die Zugabe von transparenteren nanoskalig dicken plättchenförmigen nichtmetallischen Partikeln, mit einer mittleren Plättchendicke von bevorzugt ca. 10 nm bis ca. 200 nm, insbesondere von ca. 20 nm bis ca. 100 nm und weiter bevorzugt von ca. 20 nm bis ca. 80 nm verstärkt. Bevorzugt werden als nicht-metallische Partikel Silikat- und Bornitrid-Partikel und weiter bevorzugt Talkum-Partikel verwendet.

In order to compensate for this disadvantage, it is possible according to the invention to proceed, for example, according to the following variants:

• variant 1 A concentration of platelet-shaped metal particles of, for example, 1.2% by weight in the barrier layer formed from binder, hardener, reactive diluent and initiator is selected. This results in more metallic and relatively non-transparent barrier layers. In order to achieve adequate crosslinking of the barrier layer despite the low transparency, a thermal hardener component is additionally added to the composition according to the invention, for example in the form of isocyanates, which can compensate for the obstruction of crosslinking by the metal platelets reflecting the UV light.
• variant 2 A concentration of platelet-shaped metal particles of, for example, 0.4% by weight is selected in the barrier layer formed from binder, hardener, reactive diluent and initiator. This results in semi-transparent barrier layers despite the content of metallic particles, so that the UV curing can be carried out with the result of a stronger cross-linking. Thus, even without the use of additional hardener components better barrier properties can be achieved. The barrier effect of the coating in this inventive approach additionally by the addition of more transparent nanoscale platelet-shaped non-metallic particles, with an average platelet thickness of preferably about 10 nm to about 200 nm, in particular from about 20 nm to about 100 nm and further preferably reinforced from about 20 nm to about 80 nm. Silicate and boron nitride particles and more preferably talcum particles are preferably used as the non-metallic particles.

For the solvent-free UV-curable barrier coatings, unmodified aluminum particles were used M0 , as well as the non-pigmented UV-curable barrier coating used as reference systems.

For the UV-curable barrier layers according to the invention were aluminum particles with the modification M1 . M2 and M3 from Example 1 in the formulations (as above in variant 1 described) was added.

In the following Table 5, the compositions of the UV-curable barrier layer formulations (according to variant 1 ) containing 1.2% by weight of aluminum particles and additional use of isocyanates as hardener component (Desmodur N 3390) and in Table 6 the compositions according to the invention of the UV-curable barrier layer formulations without addition of isocyanate hardener (according to Variant 2 ), with a metal particle content of only 0.4% by weight and in some cases additional addition of non-metallic, nanoscale thick (platelet thickness about 80 nm) talc LP30 silicate (talcum) particles (LITHOS Industrial Minerals GmbH).

As metal platelets were inventively ( M1 . M2 . M3 ) modified aluminum particles (platelet thickness about 50 nm) from Example 1 in the UV-curing barrier coatings P18 . P19 and P20 and in the UV reference coating 3 ( P17 ), the non-surface-modified aluminum particles ( M0 ) used. Another reference system was the corresponding non-pigmented UV clearcoat as a UV reference coating 4 ( P16 ) were included in the study.

The component Desmolux U 680H (Allnex, formerly Bayer) corresponds in the UV-curable formulations of the binder component, Desmodur N 3390 BA (Covestro, formerly Bayer) of the isocyanate hardener component, Laromer HDDA (BASF) to the reactive diluent hexanediol diacrylate and Genocure ITX (Rahn) the photoinitiator. Byk 306 represents, in particular, an additive which is frequently used for the prevention of surface defects in paint applications. For the preparation of the corresponding UV-curing barrier layer formulations, 10 g of the respective differently surface-modified aluminum particles were added as a 10% by weight paste, which corresponds to about 1, 2 wt .-% aluminum particle content corresponds, based on the resulting from Desmolux, Desmodur, the photoinitiator, or the wetting additive, and the reactive diluent HDDA solid. This greatly reduced content of aluminum particles was chosen because of the otherwise expected greatly reduced through-curing of the UV-curing systems. Table 5 Barrier layer formulations (according to variant 1) with aluminum particles (P18 to P20) modified according to the invention, reference formulation 3 (P17) which corresponds to effect lacquers, and reference formulation 4 according to the prior art for UV-curing clearcoats (P16). P16 sample without particles P17 sample with particles P18 sample with particle M1 P19 sample with particle M2 P20 sample with M3 particle Desmolux U 680H (80% in HDDA) [g] 41,90 41,90 41,90 41,90 41,90 Desmodur N 3390 BA [g] 2.74 2.74 2.74 2.74 2.74 Laromer HDDA [g] 37.56 37.56 37.56 37.56 37.56 Irgacure 184, 50% in HDDA [g] 5.64 5.64 5.64 5.64 5.64 Genocure ITX [g] 2.00 2.00 2.00 2.00 2.00 Byk 306 [g] 0.16 0.16 0.16 0.16 0.16 10% by weight of aluminum particles Decomet 3008/10 - Paste M0 (untreated) [g] - 10.00 - - - 10% by weight of aluminum particles Decomet 3008/10; paste M1 [g] - - 10.00 - - 10% by weight of aluminum particles Decomet 3008/10; paste M2 [g] - - - 10.00 10% by weight of aluminum particles Decomet 3008/10; paste M3 [g] - - - - 10.00 Table 6 Barrier layer formulations (according to variant 2) without addition of isocyanate hardener, with an aluminum particle content of 0.4% by weight and partly additional addition of non-metallic silicate (talcum) particles (platelet thickness about 80 nm) with the aluminum Particle (P22, P23), Reference Formulation 5 (P21), which corresponds to effect pigment lacquers, and Reference Formulation 4 according to the prior art for UV-curing clearcoats (P16). P16 sample without particles P21 sample with aluminum particle M2 P22 sample with aluminum particles M2 and Talc LP30 P23 sample with aluminum particle M2 and Talc LP30 Desmolux U 680H (80% in HDDA) [g] 47.72 47.72 47.72 47.72 Laromer HDDA [g] 41.98 41.98 41.98 41.98 Irgacure 184, 50% in HDDA [g] 5.64 5.64 5.64 5.64 Genocure ITX [g] 2.00 2.00 2.00 2.00 Byk 306 [g] 0.16 0.16 0.16 0.16 10% by weight of aluminum particles Decomet 3008/10 - Paste M2 [g] - 3.50 3.50 3.50 Talc particles LP30 [g] - - 0.70 1.40

The UV-curable barrier layer formulations were applied to a 34 μm thick low-density polyethylene LDPE film by means of a doctor blade application to achieve a dry film thickness of about 10 μm.

The OTR (Oxygen Transmission Rate) values obtained were again in each case based on 10 μm by multiplying by the mean value of the actual layer thickness and then dividing by 10 μm. The OTR values obtained in this way were in each case indicated as OTR / 23 ° C / 10 μm in the unit ml / m ² / day. The measurement of the OTR values was carried out according to the Standard ISO 15105-1: 2007-10 ,

In 6 the oxygen permeability values OTR (Oxygen Transmission Rate) obtained for the individual UV barrier coating at 23 ° C. are shown. Compared to the OTR values obtained for the coated films, the uncoated LDPE film was measured to have an OTR of 3091 ml / m ² / day. The results further indicate that, provided an optimized surface modification of the barrier particles, in contrast to the barrier effect against water from Example 2, even relatively low addition amounts of the invention surface-modified barrier particles, very good barrier coatings against gases such as oxygen, give. As a result, the following ranking of the UV-curable barrier coatings can be given for the oxygen barrier effect (ordered from higher to lower barrier): $$\mathbf{P}1\mathrm{8th}>P20>P19>>P17>>ReferenzOHnePartikelP16$$

Out 6 Thus, it can be deduced that the UV-curable reference barrier layers on the LDPE films formulated without particles and the UV-curable reference barrier layers containing the unmodified aluminum particles have the least oxygen barrier properties. The LDPE films, however, which were coated with the UV-curable barrier layers containing the modified aluminum particles according to the invention, show very good oxygen barrier properties. The highest oxygen barrier could be achieved with the UV-curable barrier layers, which with the surface modification according to the invention M1 coated aluminum particles contained.

In 7 For example, the OTR (oxygen transmission rate) oxygen permeability values for the individual UV-curable barrier layers on LDPE films at 23 ° C. are comparative for the barrier layer formulations without addition of isocyanate hardener, with a metal particle content of 0.4% by weight with the obtained oxygen permeability values OTR for the barrier layer formulations with additional addition of non-metallic nanoscale thick (platelet thickness about 80 nm) silicate (talc) particles ( P21 . P22 ). As another reference, the LDPE film coated with UV-curing lacquer without metal particles was in turn taken up.

Compared to the obtained OTR values for the coated films in 6 with the barrier layer formulations containing 1.2% by weight of aluminum particles ( M2 ) and additional use of isocyanate as hardener component ( P19 ), shows the isocyanate-free, but only with 0.4 wt .-% metal particles ( M2 ) LDPE film ( P21 ) a significantly improved barrier effect. Now 0.8 wt .-% nanoscale talc Talc LP30 particles are added so that the total particle content is in each case 1.2 wt .-% (isocyanate and aluminum particles containing reference P19 with 1.2% by weight of aluminum particles M2 ), so be with the sample P22 containing only 0.4% by weight of aluminum particles M2 , but additionally consists of 0.8 wt .-% talc LP30, and in particular with the sample P23 , which consists of 0.4 wt .-% aluminum particles M2 and in addition 1.6 wt .-% talc LP30, the barrier properties of the UV-curing coating again significantly improved.

Based on the results obtained it can therefore be stated that it is useful for transparent and cost-effective coatings, in particular for UV-curable barrier coatings, with good UV transparency and thus improved through hardening, as well as for cost optimization, mixtures of metal and to use non-metallic nanoscale thick platelet-shaped particles in barrier layers according to the invention.

The results obtained can be transferred to other coating matrices, coating systems and matrix polymers, so that mixtures of metal and non-metallic nanoscale platelet-shaped particles are advantageously used to advantage in barrier layers, where cost optimization combined with transparency and efficient barrier properties are particularly important ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• CN 201576687 U [0010]
• JP 2001006631 A1 [0011]
• US 4601943 A [0012]
• DE 10152266 C1 [0013]
• WO 2008/034733 A1 [0014]
• EP 2069210 B1 [0014]
• DE 19650286 A1 [0016]
• WO 0166654 A1 [0018, 0095]
• WO 0166655 A1 [0018, 0095]
• WO 0166656 A2 [0019]
• WO 0166662 A2 [0019]
• DE 10350125 A1 [0020, 0095]

Cited non-patent literature

• DIN EN ISO 139 [0059]
• DIN EN ISO 2808: 2004 [0059]
• DIN EN ISO [0098]
• DIN EN ISO 6270 [0099]
• Standard ISO 15105-1: 2007-10 [0120]

Claims (23)

Composition for the preparation of a barrier layer, comprising a polymer component, surface-modified platelet-shaped inorganic particles, in particular in the form of metal-, metal oxide- and silicate-based particles, and a proportion of an organic solvent, which optionally comprises a reactive diluent, wherein the particles are modified on their surface with one or more double bond-functional and / or epoxide-functional reactive silane components and with one or more amino-functional components, wherein the particles have a nanoscale platelet thickness, and wherein the polymer component is selected from polyacrylates, polyvinylidene chlorides, polyurethanes, polyesters and cellulose derivatives. Composition after Claim 1 , wherein the platelet-shaped particles are selected from metal, oxidic and nitridic particles, and in particular are selected from the group consisting of aluminum particles, alumina particles, glass particles, aluminum silicate particles, silicate particles and boron nitride particles of platelet-shaped particles and mixtures of these particles. Composition after Claim 2 wherein the mixture of platelet-shaped particles comprises aluminum and silicate particles. Composition according to one of Claims 1 to 3 wherein the platelet-shaped particles have an average thickness of about 10 nm to about 200 nm, preferably from about 20 nm to about 100 nm, and more preferably from about 20 nm to about 80 nm. Composition according to one of Claims 1 to 4 , wherein as platelet-shaped particles metal particles are included, which are preferably corrosion-passivated nanoscale platelet-shaped aluminum particles. Composition according to one of Claims 1 to 5 , wherein the platelet-shaped particles are modified with at least one double bond-functional and additionally with at least one epoxide-functional reactive silane component. Composition according to one of Claims 1 to 6 in which the double-bond-functional reactive silane component is preferably an olefinically reactive silane component, which is preferably selected from vinyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane and mixtures thereof. Composition according to one of Claims 1 to 7 wherein the epoxide functional reactive component is a 3-glycidyloxypropyltrimethoxysilane. Composition according to one of Claims 1 to 8th wherein the amino-functional component is selected from a multifunctional low molecular weight aliphatic, aromatic, heterocyclic component, amino-functional polyether components, 2-aminoethyl-3-amino-propyltrimethoxysilane and 3-aminopropyltrimethoxysilane and mixtures thereof. Composition according to one of Claims 1 to 9 wherein the proportion of platelet-shaped particles in the composition about 0.1 to about 60 wt .-%, in particular about 1 to about 40 wt .-% and more preferably about 1 to about 30 wt. -%, based on the proportion of the polymer component. Composition according to one of Claims 1 to 10 wherein the composition comprises nanoscale thick platelet-shaped silicate particles in a proportion of about 0.1 wt .-% to about 8 wt .-%, based on the proportion of the polymer component, and preferably further comprises a proportion of nanoscale thick platelet-shaped Aluminum particles in a weight ratio of the aluminum particles to the silicate particles in the range of about 100: 1 to about 1: 5. Composition according to one of Claims 1 to 11 wherein the composition for generating a barrier effect against the permeation of water and water vapor about 30 wt .-% to about 60 wt .-%, preferably about 50 wt .-% to about 58 wt .-% surface-modified nanoscale thick Particles, in particular aluminum particles, comprises, based on the proportion of the polymer component. Barrier layer, obtained from a composition according to one of Claims 1 to 12 , with a layer having a dry film thickness of about 0.1 to about 20 microns, more preferably from about 0.5 to about 10 microns, and more preferably from about 0.5 to about 6 microns, comprising the surface-modified platelets shaped particles embedded in a polymer matrix of the polymer component. Barrier layer after Claim 13 , wherein the layer is thermally and / or UV-crosslinked with the involvement of a reactive diluent. Barrier layer after Claim 13 or 14 , wherein the barrier coating with one or more thicker, particle-free, also thermoset layers having a layer thickness of about 4 .mu.m to about 60 .mu.m, preferably from about 10 .mu.m to about 40 .mu.m, more preferably from about 15 .mu.m to about 25 μm, overcoated. Barrier layer after one of the Claims 13 to 15 in which the barrier layer has a superficial lacquer layer region about 10 μm to about 40 μm, in particular about 15 μm to about 25 μm thick, preferably particle-free, and an underlying about 0.5 μm to about 6 μm, in particular ca. 0.7 micron to about 1 micron thick surface-modified, nanoscale thick platelet-shaped particles containing layer area comprises. Barrier layer after Claim 16 , wherein the underlying layer about 30 wt .-% to about 60 wt .-% surface-modified nanoscale thick platelet-shaped particles, based on the proportion of the polymer component containing. Barrier layer after one of the Claims 13 to 16 in which the layer comprising the surface-modified, nanoscale thick platelet-shaped particles contains from about 1% by weight to about 30% by weight of surface-modified, nanoscale aluminum particles, and furthermore preferably has a proportion of about 0, 1 wt .-% to about 8 wt .-% surface-modified, nanoscale thick silicate particles comprises, in each case based on the proportion of the polymer component. Barrier layer after one of the Claims 13 to 18 wherein the barrier layer comprises additional white or black pigments and in particular is colorless white or dark formulated and more preferably has no metallic effects. Use of a composition according to one of Claims 1 to 12 for producing a barrier layer on a substrate, in particular for producing a barrier layer on metal, paper, cardboard and plastic substrates and combinations thereof, in particular for producing a barrier layer on plastic packaging and molded articles, more preferably on plastic cartridges, plastic capsules , Plastic films and plastic bottles, which are preferably based on polyamide (PA), polyethylene (HDPE, LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyacrylate, polyester, polylactide (PLA) and polycarbonate (PC ) are made. Use after Claim 20 in that at least one barrier layer of a multilayer structure having a plurality of different layers and / or a multilayer structure having a plurality of identical layers is produced from the composition, preferably on metal or plastic surfaces and more preferably on two opposite sides, for example on inner and outer sides of moldings or films , With a barrier layer coated substrate in the form of a shaped body, a hollow body, a flat substrate or a film with an internally and / or externally applied barrier layer according to one of Claims 13 to 19 , A method of applying a barrier layer to a substrate, the method comprising the steps of: providing a composition according to any one of Claims 1 to 12 ; and applying the composition to a surface of the substrate by doctoring or a printing process; wherein the substrate is preferably a film, in particular a packaging film.

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