Low PTFE structuring agent for powder paints

Abstract

The present invention relates to low-PTFE or PTFE-free compositions that can be added to powder coating formulations to enhance the roughness / structuring of the powder coating. The present invention further relates to methods for making the compositions. The present invention also relates to low-PTFE or PTFE-free powder coatings with improved structuring properties and methods for making the powder coatings.

Description

[Technical Field]

[0001] The present invention relates to a low PTFE powder coating additive for producing a powder coating having a structured surface. [Background technology]

[0002] Powder coatings are used for solvent-free painting of metals (35%), household appliances (21%), facades (20%), furniture (13%) and automobiles. Many applications require structured coatings. These are achieved by adding polytetrafluoroethylene (PTFE) or by modifying individual components with PTFE.

[0003] Additives for modifying the properties and surfaces of powder coatings are widely known. For example, individual components of the compositions of the present invention have been previously described as powder coating additives. However, these components do not function as PTFE-free structurants, but rather modify other properties of the powder coating.

[0004] Patent Document 1 (CN112724799A) discloses a powder coating containing a modified polyethylene wax and unmodified bentonite in a structuring additive intended to impart a sandy surface to the powder coating. The bentonite is added to the powder coating for gloss adjustment. The method of modifying the polyethylene wax is not disclosed.

[0005] Patent Document 2 (CN103160192) discloses a powder coating containing a micronized PTFE-modified polyethylene wax, micronized organophilic modified bentonite, and numerous other ingredients. The inventors believe that the PTFE modification is necessary for structuring properties. Modification of the polyethylene wax with α,β-unsaturated carboxylic acids and / or their derivatives is not considered.

[0006] Patent Document 3 (JP4818822B2) discloses a thixotropic agent consisting of oxidized polyethylene wax and bentonite, and a paint containing the thixotropic agent. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] CN112724799 [Patent Document 2] CN103160192 [Patent Document 3] JP4818822B2 Summary of the Invention [Problem to be solved by the invention]

[0008] Persistent fluorine compounds are the subject of criticism and regulation (POPs, EU Regulation 2019 / 1021). They can be generated as by-products in the production of PTFE or during PTFE processing. Therefore, there is a need to provide low-PTFE or PTFE-free alternatives for structuring powder coating surfaces. Furthermore, it would be advantageous to be able to establish different degrees of structuring effect using structuring additives. [Means for solving the problem]

[0009] Surprisingly, it has been found that the surface of powder coatings can be structured without the addition of PTFE by adding a mixture of wax modified with an α,β-unsaturated carboxylic acid and modified bentonite to the coating raw materials before baking.

[0010] As an indicator of the structuring of a powder coating surface, the roughness value (Rz) can be measured according to EN ISO 4287:1997, which indicates the average height of the surface irregularities. The higher the roughness value, the more structured the surface.

[0011] The present invention provides a composition (C) comprising, as essential components, (a) at least one modified wax (MW) modified by grafting with an α,β-unsaturated carboxylic acid and / or its derivative, and (b) a modified phyllosilicate (MP), preferably an organophilic modified phyllosilicate (OMP), which ensures structuring of the surface of a powder coating without the need for the addition of a PTFE-containing structurant. The present invention also provides the use of composition (C) for structuring a powder coating.

[0012] The present invention further provides a method for producing the composition (C) of the present invention, which method comprises the steps of mixing an optionally finely divided modified phyllosilicate (MP), an optionally finely divided modified wax (MW) modified by grafting with an α,β-unsaturated carboxylic acid and / or its derivative, and any additional components, and optionally finely dividing the components by hot mixing, extruding, grinding or agitating.

[0013] The present invention also provides a powder coating composition (PC) comprising: a) at least one thermoplastic or post-bake thermosetting polymer; b) at least one modified wax (MW) modified by grafting with an α,β-unsaturated carboxylic acid and / or its derivative; and c) at least one modified phyllosilicate (MP). The present invention also provides a method for producing the powder coating composition (PC), which comprises extruding all essential components of the powder coating together with (i) composition (C) or (ii) the components of composition (C), followed by grinding. Alternatively, (i) finely divided composition (C) or (ii) the finely divided components of composition (C) can be mixed with the ground and optionally sieved powder coating composition. [Brief explanation of the drawings]

[0014] [Figure 1] Roughness values ​​(Rz) of Examples 1 to 14 in the Examples DETAILED DESCRIPTION OF THE INVENTION

[0015] Modified wax (MW) The modified wax, a component of composition (C), can in principle be any wax. For example, wax (W) can be selected from the group consisting of synthetic organic waxes, semi-synthetic organic waxes, natural waxes (bio-based waxes), and mixtures thereof, and the waxes are chemically modified. Unmodified waxes are modified by grafting with α,β-unsaturated carboxylic acids and / or their derivatives (e.g., acrylic acid or maleic anhydride).

[0016] Suitable wax components are synthetic hydrocarbon waxes, such as polyolefin waxes. These can be produced by pyrolysis of branched or unbranched polyolefin polymers or by direct polymerization of olefins. Useful polymerization methods include, for example, free radical processes in which olefins (typically ethylene) are converted to polymer chains with greater or lesser degrees of branching at high pressure and temperature. A further useful method is the polymerization of ethylene and / or higher 1-olefins (e.g., propylene, 1-butene, 1-hexene, etc.) using organometallic catalysts (e.g., Ziegler-Natta catalysts or metallocene catalysts) to obtain unbranched or (short-chain) branched waxes.

[0017] Methods for producing olefin homo- and copolymer waxes are described, for example, in chapters 6.1.1. / 6.1.2. (High-Pressure Polymerization), (Waxes), 6.1.2. (Ziegler-Natta Polymerization, Polymerization with Metallocene Catalysis) and 6.1.4. (Pyrolysis) of Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, vol. A 28, Weinheim 1996.

[0018] Also usable as such waxes are sustainably produced polyolefins obtained from renewable or recycled raw materials. For example, EP2352772 describes a method for producing polypropylene polymers from renewable raw materials. US2022098490 describes a process for producing polyolefins from plastic waste.

[0019] Furthermore, it is also possible to use so-called Fischer-Tropsch waxes, which are produced catalytically from synthesis gas and differ from polyethylene waxes in that they have a low average molar mass, a narrow molar mass distribution and a low melt viscosity.

[0020] Furthermore, bio-based waxes can also be used, typically ester waxes. Bio-based waxes generally refer to waxes based on renewable raw materials. These may be natural or chemically modified ester waxes. Typical natural bio-based waxes are listed in Chapter 2 of Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, vol. A 28, 1996. These include palm waxes such as carnauba wax, grass waxes such as candelilla wax, sugarcane wax and straw wax, beeswax, rice wax, etc.

[0021] Chemically modified waxes are typically formed by oxidation (e.g., with a mixture of CrO3 and H2SO4), esterification, transesterification, amidation, hydrogenation, etc. of fatty acids derived from ester waxes or vegetable oils. Examples of these include the metathesis products of vegetable oils.

[0022] Such bio-based waxes also include montan wax in unmodified or purified / derivatized form, details of which are described, for example, in Chapter 3 (Waxes) of Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, vol. A 28, 1996.

[0023] In a preferred embodiment, the modified wax (MW) is selected from the group consisting of polyolefin waxes, montan waxes, rice bran waxes, beeswax waxes, sunflower waxes, corn waxes, carnauba waxes, oxides (of rice bran wax, sunflower wax, corn wax or carnauba wax), Fischer-Tropsch waxes, paraffin waxes, ester waxes and amide waxes.

[0024] Among these waxes, polyethylene wax, polypropylene wax, poly(ethylene-co-propylene) wax, and oxides of rice bran wax, corn wax, or sunflower wax are particularly suitable because they have relatively high melting points and inherently light colors. These waxes are particularly suitable for powder coatings because of their optical neutrality and chemical stability, which are important in the powder coating manufacturing process.

[0025] Particularly preferred are polyethylene waxes, polypropylene waxes and poly(ethylene copropylene) waxes, as these are phase intermediary materials (non-polar polymer backbones with polar grafts) that interact between binders and fillers and are specifically designed for modification by grafting with α,β-unsaturated carboxylic acids and / or their derivatives, with little or no undesired side reactions occurring.

[0026] Modified phyllosilicates (MP) Phyllosilicate refers to silicates consisting of layers of SiO tetrahedra with corner-linked silicate anions. These layers or bilayers are not interconnected to form a framework by additional Si-O bonds.

[0027] Such phyllosilicates occur in natural clays. Clays are classified by their predominant mineral component (e.g., kaolinite clays, smectite-rich clays). Clays in which the predominant clay mineral is a phyllosilicate are classified by the phyllosilicate.

[0028] Thus, phyllosilicates herein include both pure phyllosilicate clay minerals and clays in which the predominant clay mineral is a phyllosilicate.

[0029] As used herein, organically modified triple-layer minerals include both pure clay minerals that are organically modified triple-layer minerals and clays in which the predominant clay mineral is an organically modified triple-layer mineral. The same definition applies to all clay minerals or clay mineral classes listed.

[0030] One type of clay of industrial importance is bentonite. In geology, the term "bentonite" is used to refer to a type of claystone (not a clay mineral, but a claystone) composed primarily of montmorillonite (a clay mineral of the smectite group). However, in commercial and industrial applications, the term "bentonite" is more generally used to refer to all swelling clays composed primarily of smectite clay minerals (montmorillonite, beidellite, and nontronite) and containing additional components such as mica, illite, cristobalite, and zeolite. This definition of bentonite applies to the present invention in this patent application. Industrially important bentonites require a montmorillonite content of 60-80%.

[0031] Phyllosilicates can be modified by ion exchange of cations or anions. It is preferred to exchange the interlayer cations with other cations. For example, the cation occupation between the layers can be changed by alkali activation to Na +It can be exchanged with ions.

[0032] Preferred are trilayer minerals (2:1 layer silicates) whose crystallographic structure consists of three overlapping layers of tetrahedron-octahedron-tetrahedron layers (TOT layer units).

[0033] The 2:1 layer structure (TOT) indicates that two tetrahedral (T) silicon dioxide (SiO2) layers are electrostatically bridged by an octahedral (O) interlayer of Al2O3 or Fe2O3. The TOT unit layers are not rigidly bonded to each other but are clearly separated by interlayers containing hydrated cations and water molecules.

[0034] The triple-layer minerals of the smectite group are particularly suitable. These include, for example, saponite, hectorite, montmorillonite, beidellite, and nontronite. Dioctahedral smectites are preferred, and montmorillonite-containing minerals, such as those present in bentonite, are particularly preferred.

[0035] These properties of triple-layer minerals, especially those of the smectite group, and more preferably bentonite, can be modified by exchanging cations between the layers.

[0036] For example, activated bentonite is originally calcium bentonite, and the original cation occupancy between the layers is changed to Na by alkali activation. + ions are exchanged. In principle, calcium bentonite is converted into sodium bentonite. In terms of physical properties, it is very similar to natural sodium bentonite. In another embodiment of the present invention, such alkali-activated bentonite can be used.

[0037] A preferred embodiment relates to organophilically modified triple-layered minerals. Such organophilically modified triple-layered minerals are prepared by inserting organic molecules between the layers or by exchanging cations between the layers with organic molecules. Organic molecules useful for organo-modification include those selected from the group consisting of polymers (nonionic, cationic, or anionic), alkylammonium compounds, alcohols (e.g., ethylene glycol, methanol, or glycerol), and carbohydrates.

[0038] The modification is preferably carried out with alkylammonium compounds, more preferably with quaternary alkylammonium compounds, and due to this hydrophobization, composition (C) in the powder coating exhibits better structuring properties than composition (C) without lipophilic modification of the phyllosilicate.

[0039] The quaternary alkylammonium compound used is preferably a dimethyldialkylammonium ion or a trimethylalkylammonium ion.

[0040] Among the modified triple-layer minerals, modified smectite or hectorite is preferred. Organophilically modified smectite or hectorite is particularly preferred. The modification is preferably carried out with an alkylammonium compound, more preferably a quaternary alkylammonium compound. Preferred examples are dimethyl distearyl ammonium hectorite, dimethyl distearyl ammonium bentonite, and dimethyl distearyl ammonium modified montmorillonite. Commercially available products include BENTONE 38 V CG (dimethyl distearyl ammonium hectorite) and BENTONE 34 (dimethyl distearyl ammonium bentonite) from Elementis Specialties, and Claytone-40 (a stearic derivative of bentonite) from Byk. One, two, or more of these organophilically modified bentonites can be used.

[0041] The organophilic modified smectite used is most preferably organophilic modified bentonite. Organophilic modified bentonite is produced by exchanging interlayer cations with alkylammonium ions, preferably quaternary alkylammonium ions. This hydrophobicity allows the bentonite to swell in nonpolar liquids. These bentonites are also called "bentones" or "organoclays." Typical applications of such bentonites include thickening greases or lubricants and coatings by using the bentonite as a rheology modifier. Preferred examples are BENTONE 34 (dimethyl distearyl ammonium bentonite) from Elementis Specialties and Claytone-40 (a stearic derivative of bentonite) from Byk. One, two, or more of these organophilic modified bentonites can be used.

[0042] Physical supply form The two main components of composition (C), the modified wax (MW) and the phyllosilicates (MP), can be added to the powder coating in various forms: they can be in the form of granules or powders.

[0043] In composition (C), the modified wax (MW) and the modified phyllosilicates (MP) are preferably in micronized form.

[0044] The term "micronized" as used herein means that the (average) particle size of the substance has been reduced compared to the original state, with less than 1% by volume of particles having a particle size of 1000 μm or greater.

[0045] The particle size distribution can be measured, for example, by laser diffraction, as described in "A Guidebook to Particle Size Analysis" (Horiba Instruments, Inc., 2019). Suitable measuring instruments for this purpose include, for example, the LA-960 from Horiba Instruments, which can measure particle sizes in the range of 10 nm to 5 mm, or the Mastersizer 3000 from Malvern Panalytical, which can measure particle sizes in the range of 10 nm to 3.5 mm.

[0046] The micronized composition (C) has a higher surface area than the non-micronized composition (C) and can be more easily and quickly homogenized into the powder coating in the extruder, thereby allowing the powder coating manufacturer to reduce the energy required to produce the powder coating.

[0047] In the composition (C), the volume median particle diameter D50 of the particle size of the modified phyllosilicate (MP) and modified wax (MW) is preferably 500 μm or less, more preferably 300 μm or less.

[0048] In another embodiment, the micronized modified phyllosilicate (MP) is wholly or partially coated with a modified wax.

[0049] The powdered modified phyllosilicate particles can be mixed particularly effectively with modified wax (MW) under high temperature conditions, which produces a flowable, finely divided powder coated with the modified wax.

[0050] In this embodiment, the modified phyllosilicate (MP) preferably has a particle size with a volume median diameter D50 of 500 μm or less, more preferably 300 μm or less.

[0051] This embodiment is particularly preferred because it reduces the energy consumption in the production of the inventive powder coating composition (PC) (where all components of the powder coating are extruded and then milled) compared to adding or otherwise mixing the main finely divided components of composition (C) separately into the inventive powder coating composition (PC), as will be described in more detail below.

[0052] Preferred Compositions PTFE-free compositions are particularly environmentally friendly, so that PTFE-free compositions (C) which provide a suitable structuring effect in baked powder coatings are clearly preferable from an environmental point of view to PTFE-containing compositions.

[0053] In a preferred embodiment, composition (C) comprises the modified wax (MW) and modified bentonite (MB), preferably lipophilic modified bentonite (OMB), in a ratio between 4:1 and 1:3, preferably between 3.5:1 and 1:2, more preferably between 3:1 and 1:1.5, and most preferably between 3:1 and 1:1.

[0054] Composition (C) is particularly effective if it contains not only the modified wax (MW) and modified phyllosilicate (MP) components essential for structuring, but also one or more basic metal compounds, preferably selected from the group of (semi)metal oxides, sulfates and hydroxides, more preferably from alkaline earth metal sulfates or oxides of transition metals of group 4 elements, particularly preferably from barium sulfate, fumed silica and titanium dioxide, since this further improves the structuring effect.

[0055] Composition (C) of the present invention may further comprise stabilizers, additives and / or flow aids, such as primary and secondary antioxidants (eg HALS compounds), or fumed silica.

[0056] Methods for making and using the compositions of the present invention The composition (C) of the present invention is prepared by mixing the components by hot mixing, extrusion, grinding or agitating, optionally with simultaneous micronization, depending on the process, where "micronization" means grinding to an average particle size of 1000 μm or less. Thus, the present invention further relates to a method for preparing the composition (C) of the present invention, said method comprising the steps of: a) providing an optionally micronized modified phyllosilicate (MP), an optionally micronized modified wax (MW), and any additional ingredients; b) mixing and optionally micronizing the ingredients provided in step a), preferably by blending, hot mixing, extrusion, or grinding.

[0057] Blending refers to physical mixing, for example by stirring, agitating, or vortexing. Hot mixing is preferred for a method of making composition (C), which comprises the steps of: a) providing and mixing finely divided modified phyllosilicate (MP) and modified wax (MW); b) heating the modified wax (MW) with stirring to a temperature within the melting point range of the wax; and c) mixing the ingredients by stirring.

[0058] The present invention further relates to the use of composition (C) for structuring powder coatings, where the use of composition (C) in powder coatings allows the surface of the powder coating to be structured with less, if any, PTFE-containing components.

[0059] Powder Coating Composition (PC) The present invention further provides a powder coating composition (PC) comprising: a) at least one thermoplastic, or post-bake thermosetting, polymer; b) at least one modified wax (MW) modified by grafting with an α,β-unsaturated carboxylic acid and / or its derivatives; and c) at least one, optionally micronized, modified phyllosilicate (MP).

[0060] Component a) is a binder. The powder coating composition (PC) preferably comprises as binder a post-bake thermosetting polymer selected from the group consisting of epoxy resins, epoxy resin / polyester hybrid systems, reactive polyesters and reactive acrylates, preferably selected from the group consisting of epoxy resin / polyester hybrid systems and hydroxyalkylamides.

[0061] In thermosetting powder coatings, the structure created by composition (C) is stable at high temperatures, whereas thermoplastic structured powder coatings, as paints, can be deformed above their melting point.

[0062] The structuring of the surface can be further improved by adding one or more basic metal compounds to the powder coating composition (PC) from the group of (semi)metal oxides, sulfates or hydroxides, more preferably selected from alkaline earth metal sulfates or transition metal oxides of group 4 elements, particularly preferably selected from barium sulfate, fumed silica and titanium dioxide. These basic metal compounds may already be present in the powder coating composition as pigments or fillers or may be added additionally.

[0063] By adding composition (C) to the powder coating composition (PC), the roughness value Rz (average roughness depth) can be increased and a high structuring effect can be obtained.

[0064] The degree of structuring effect can be adjusted to be more advantageous than that of the PTFE-containing structuring additive by selecting an amount within the range of 0.5% to 10% by weight, preferably 2% to 8% by weight, based on the total weight of the powder coating composition (PC). In contrast, with the PTFE-containing structuring additive, a significant structuring effect is established even at very low amounts without such effective adjustment.

[0065] The important factor for the surface roughness of the powder coating composition (PC) is the content ratio of the essential components of the composition (C). High roughness values ​​are obtained when the wax (MW) to bentonite (OMB) ratio is between 4:1 and 1:3, preferably between 3.5:1 and 1:2, more preferably between 3:1 and 1:1.5, and most preferably between 3:1 and 1:1.

[0066] Powder coatings containing low amounts of PTFE are more environmentally friendly than those containing high amounts of PTFE. The present invention preferably provides powder coating compositions (PC) containing less than 1 wt. % PTFE, preferably less than 0.5 wt. %, more preferably less than 0.1 wt. %, and most preferably no PTFE.

[0067] The powder coating composition (PC) of the present invention is produced by a method for producing a powder coating composition (PC) comprising the following steps: a) preparing all necessary components of the powder coating composition and composition (C) or (ii) the individual components that composition (C) comprises; b) mixing the components prepared in step a) by extrusion; c) grinding the extruded powder coating composition prepared in step b).

[0068] Optionally, the powder coating composition ground in step c) can then be sieved.

[0069] In another embodiment, (i) composition (C) or (ii) the individual components of composition (C) are added and mixed into the powder coating composition (PC) after manufacturing step c).

[0070] experiment The examples illustrate some preferred embodiments of the present invention. Table 1: Measurement methods for reported parameters

[0071] [Table 1]

[0072] Example setup Table 2: Materials and compositions used

[0073] [Table 2]

[0074] Preparation of composition (C) of the present invention Compositions Z1 to Z4 were prepared by hot mixing using a 1968 Guenther Papenmeier TLHK3 Turbofluid Mixer. For this purpose, in each case, the modified wax (MW) and the organophilic modified bentonite (OMB) were weighed in the appropriate proportions and blended together by stirring. The mixture was then heated to a temperature within the melting point range of the wax while stirring, stirred for a further 10 minutes, and then cooled while stirring. Components W and B from Table 2 were mixed by agitation before being added to the powder coating composition. Alternatively, the components of the powder coating composition were added directly.

[0075] Preparation of the powder coating compositions (PC) of the present invention and corresponding coatings: The ingredients listed in Tables 3 to 5 were premixed in a mixer at maximum power for 3 minutes and then mixed in the extruder at approximately 110°C (extruder temperature), ensuring that the temperature of the mixture did not exceed 140°C. A) Primid System Zone 1: RT; Zone 2: 90°C; Zone 3: 100°C; Zone 4: 100°C B) Hybrid system Zone 1: RT; Zone 2: 90°C; Zone 3: 100°C; Zone 4: 100°C

[0076] The powder coating was then crushed and sieved to less than 125 μm, with a D50 value of approximately 40-45 μm. The powder coating composition was then sprayed onto a metal substrate (aluminum). The powder coating was baked at 180°C for 15 minutes. Table 3: Formulation of colored hybrid system L1

[0077] [Table 3]

[0078] Table 4: Components (SC) of L1 (Hybrid Blue)

[0079] [Table 4]

[0080] Table 4 shows that composition (C) consisting of MA-grafted wax and organophilically modified bentonite achieves higher roughness values ​​Rz (Examples 4-9) than the two components used alone (Examples 2 and 3). Compositions containing bentonite modified in a different manner instead of organophilically modified bentonite exhibit a relatively small structuring effect (Examples 10-12). As shown in Examples 13 and 14, the functionality of the wax used plays a particularly important role in structuring. Neither Example 13, which contains an unfunctionalized wax, nor Example 14, which contains a polar polyolefin, exhibits a structuring effect. Therefore, the method of modification of the polyolefin plays a decisive role in the formation of the structuring. Particularly significant structuring is obtained when composition (C) additionally contains a certain amount of PTFE.

[0081] A plot of the roughness values ​​of the powder coating composition (PC) in L1 without PTFE is shown in FIG. Table 5: Formulation of White Hybrid System L2

[0082] [Table 5]

[0083] Table 6: Structuring Components (SC) in L2 (Hybrid White)

[0084] [Table 6]

[0085] In the white hybrid coating, the addition of 4 wt. % of composition Z2 according to the invention results in a stronger structuring effect than with conventional amounts of PTFE-containing additives (see Table 6). Table 7: Primid System L3 Formulation

[0086] [Table 7]

[0087] Table 4: Structuring components (SC) in L3 (Primido Blue)

[0088] [Table 8]

[0089] Table 4 shows that the addition of composition (C) results in structuring of the powder coating, which can be adjusted by the amount of composition (C). It also shows that when the ratio of modified wax (MW) to modified bentonite (MB) is 2:1 (Example 1, Z1), a higher structuring effect is obtained than when the ratio is lower (Examples 2-3).

Claims

1. (a) at least one modified wax (MW) modified by grafting with an α,β-unsaturated carboxylic acid and / or its derivatives; and (b) A composition (C) for structuring powder coatings, comprising a modified phyllosilicate (MP), preferably an organophilic modified phyllosilicate (OMP).

2. Composition (C) of claim 1, wherein the modified phyllosilicate (MP) is a modified triple-layer mineral, preferably a modified smectite or a modified hectorite, more preferably a modified bentonite (MB), and most preferably an organophilic modified bentonite (OMB).

3. 3. Composition (C) according to claim 1 or 2, wherein the modified phyllosilicate (MP) is organophilically modified, preferably modified with an alkylammonium compound, more preferably modified with a quaternary alkylammonium compound.

4. Composition (C) of any one of claims 1 to 3, wherein the modified wax (MW) and the modified phyllosilicate (MP) are in micronized form, or the modified phyllosilicate (MP) is wholly or partially coated with the modified wax (MW).

5. Composition (C) of any one of claims 1 to 4, wherein the modified wax (MW) is selected from the group consisting of synthetic organic waxes, semi-synthetic organic waxes, natural waxes, and mixtures thereof, preferably selected from polyolefin waxes, montan wax, rice bran wax, beeswax wax, sunflower wax, corn wax, carnauba wax, Fischer-Tropsch wax, paraffin wax, ester wax, and amide wax, more preferably selected from polyethylene waxes, polypropylene waxes, poly(ethylene copropylene) waxes, rice bran wax, corn wax, and sunflower wax, more preferably selected from polyethylene waxes, polypropylene waxes, and poly(ethylene copropylene) waxes.

6. Composition (C) of any one of claims 1 to 5, wherein the weight ratio of modified wax (MW) to modified phyllosilicate (MP), preferably to modified bentonite (MB), more preferably to organophilic modified bentonite (OMB) is between 4:1 and 1:3, preferably between 3.5:1 and 1:2, more preferably between 3:1 and 1:1.5, and most preferably between 3:1 and 1:

1.

7. 7. Composition (C) according to any one of claims 1 to 6, comprising one or more basic metal compounds, preferably selected from the group of (semi)metal oxides, sulfates or hydroxides, more preferably from alkaline earth metal sulfates or transition metal oxides of group 4 elements, particularly preferably from barium sulfate, fumed silica and titanium dioxide.

8. Composition (C) of any of claims 1 to 7, wherein composition (C) contains less than 1 wt. % of PTFE, preferably less than 0.5 wt. %, more preferably less than 0.1 wt. %, and most preferably no PTFE.

9. a) providing an optionally micronized modified phyllosilicate (MP), an optionally micronized modified wax (MW), and any additional ingredients; b) mixing and optionally pulverizing the components provided in step a), preferably by blending, hot mixing, extrusion or grinding; A method for producing the composition (C) of any one of claims 1 to 8, comprising:

10. a) providing and mixing the micronized modified phyllosilicate (MP) and the modified wax (MW); b) heating the modified wax (MW) with stirring to a temperature within the melting point range of the wax; c) mixing the ingredients by stirring; The method of claim 9, comprising:

11. Use of a composition (C) according to any of claims 1 to 8 for structuring powder coatings.

12. A powder coating composition (PC) comprising: a) at least one thermoplastic or post-bake thermosetting polymer; and b) composition (C).

13. 13. The powder coating composition (PC) of claim 12, wherein the post-bake thermosetting polymer is selected from the group consisting of epoxy resins, epoxy resin / polyester hybrid systems, reactive polyesters, or reactive acrylates, preferably selected from the group consisting of epoxy resin / polyester hybrid systems, and hydroxyalkylamides.

14. 14. Powder coating composition (PC) according to claim 12 or 13, comprising inorganic additives, preferably one or more basic metal compounds selected from the group of (semi)metal oxides, sulfates and hydroxides, more preferably from sulfates of alkaline earth metals and oxides of group 4 transition metal elements, particularly preferably from barium sulfate, fumed silica and titanium dioxide.

15. 15. The powder coating composition (PC) according to any of claims 12 to 14, wherein the amount of said composition (C) in the powder coating composition (PC) is between 0.5 and 10 wt.%, preferably between 2 and 8 wt.%, based on the total weight of the powder coating composition (PC).

16. 16. A powder coating composition (PC) according to any of claims 12 to 15, wherein the weight ratio of modified wax (MW) to modified phyllosilicate (MP), preferably to modified bentonite (MB), more preferably to organophilic modified bentonite (OMB) is between 4:1 and 1:3, preferably between 3.5:1 and 1:2, more preferably between 3:1 and 1:1.5, most preferably between 3:1 and 1:

1.

17. 17. The powder coating composition (PC) of any of claims 12 to 16, wherein the powder coating composition (PC) comprises less than 1 wt.%, preferably less than 0.5 wt.%, more preferably less than 0.1 wt.% of PTFE, and most preferably is free of PTFE.

18. a) providing all the necessary components of the powder coating composition, and (i) composition (C), or (ii) the individual components that composition (C) comprises; b) mixing the components provided in step a) by extrusion; c) grinding the powder coating composition extruded in step b); d) optionally sieving the ground powder coating composition obtained in step c); A method for producing a powder coating composition (PC) according to any one of claims 12 to 17, comprising:

19. a) providing a ground and optionally sieved powder coating composition without composition (C); b) mixing the powder coating composition with (i) finely divided composition (C) or (ii) an individual finely divided component of composition (C); A method for producing a powder coating composition (PC) according to any one of claims 12 to 17, comprising:

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