Multilayer effect pigments consisting of biodegradable polymers

Abstract

The invention relates to effect pigments and multilayer foils consisting of two or more biodegradable polymer layers having different refractive indices and in alternating order, to a method for the production thereof, and to the use thereof, in particular in cosmetics, rinse-like products, packaging materials, decorative foils, paints, printing inks and plastics.

Description

Technical Field

[0001] The invention relates to effect pigments and multilayer foils composed of two or more biodegradable polymer layers having different refractive indices in an alternating sequence, to a process for their production and to their use, in particular in cosmetics, wash-off products, packaging materials, decorative foils, lacquers, printing inks and plastics. Background Art

[0002] Conventional decorative or effect foils usually consist of uniaxially or biaxially stretched polyester foils, which consist, for example, of alternating polymer layers, such as PET (polyethylene terephthalate) and PBT (polybutylene terephthalate). Stretching the multilayer foils leads to different degrees of orientation and therefore to different degrees of refraction in the alternating layers and thus to angle-dependent color effects. Individual color shades can be adapted by additional coloring of the foil, for example with solvent dyes. Optionally, by applying a metal layer, usually aluminum, a barrier effect combined with a reflective effect can be additionally provided. This type of foil is used as packaging material, for example for gifts, flowers and foods. From such foils, glitter particles can be produced, for example by grinding, cutting or punching, which are used in cosmetics, rinse-off products such as shower gels or in toys.

[0003] The ordered arrangement of the polymer chains during the drawing process requires the use of polyesters having aromatic dicarboxylic acids, in particular terephthalic acid, as monomer components. However, these materials are not biodegradable and are not currently economically feasible to obtain from renewable raw material sources. Summary of the invention

[0004] The object of the present invention is therefore to produce biodegradable effect pigments and multilayer foils from sustainable raw materials (i.e. composed of a proportion of >50% bio-based raw materials), which consist of biodegradable polymers but do not contribute to a further increase of microplastics in the environment, which preferably require neither metal nor inorganic layers and can be produced in a simple and economical process from commercially available starting materials in a wide variety of colors.

[0005] According to the invention, this object is achieved by effect pigments and multilayer foils as described and claimed in the present application. In particular, it has surprisingly been found that this object can be achieved by obtaining pigments from multilayer foils, which consist of a plurality of, for example, 64 to 256, optically active individual layers, which are alternately formed, and which consist only of two polymers with different refractive indices, which are commercially available and preferably available from natural sources and are biodegradable. The polymer layers can be extruded, cut and stacked simultaneously, do not need to be stretched subsequently, and show very good adhesion without additional auxiliaries, and, depending on the layer thickness and the refractive index, show a metallic appearance color effect due to interference. These multilayer foils can be comminuted into particles of suitable size, for example by grinding, cutting or stamping, which can then be used as effect pigments.

[0006] Furthermore, it has surprisingly been found that a material combination of the two commercially available and biodegradable polymers polylactide (in particular as a D / L copolymer) and PBAT (polybutylene adipate terephthalate), in particular as a statistical copolymer, is particularly well suited for use in the effect pigments and multilayer foils according to the invention.

[0007] US6299979 describes a polymeric colored effect pigment comprising a plurality of layers of thermoplastic organic materials having different refractive indices. However, no biodegradable materials are mentioned therein.

[0008] US 2007 / 014977 A1 describes a multilayer iridescent foil consisting of alternating biodegradable polylactic acid layers and non-biodegradable polyester terephthalate layers. The foil is produced by coextrusion of the two polymers and then preferably stretched to increase the refractive index difference and to obtain a more intense color tone. It is also described that the foil can be comminuted to produce iridescent particles. However, the polyester terephthalate foil used is not biodegradable and is not economically feasible from renewable raw material sources. In addition, the additional method step of stretching the foil means a higher time and cost expenditure for the production process.

[0009] US 2013 / 0295355 A1 describes a biodegradable multilayer transparent and flexible packaging foil, which is composed of at least one first polymer layer based on PLA and aliphatic or aliphatic-aromatic second copolyester layer arranged alternately, wherein the first polymer layer forms an outer layer. Optionally, this foil can also comprise a third polymer layer composed of aliphatic or aliphatic-aromatic polymers based on polyester, which is different from the second polymer layer and is arranged between the first and second polymer layers. This multilayer foil is prepared by melt extruding every kind of polymer and laminating extrudate in turn and stretching subsequently. In addition, the individual layer thickness of the polymer layer is described to be between 133 and 5000 nm, because for described transparent foil, when individual layer thickness is less than 133nm (refractive index n=1.465), undesirable interference occurs in the visible wavelength range, especially red interference occurs at 780 nm. However, due to this lower limit of individual layer thickness, the available parameter space for obtaining other different tones is severely limited. In addition, the other method steps of stretching foil mean the higher time and cost consumption of preparation process.

[0010] However, the effect pigments and multilayer foils according to the invention and the advantages achieved thereby are neither described nor suggested by the prior art.

[0011] Therefore, one subject of the present invention is an effect pigment which comprises, preferably consists of, two or more transparent layers of a first polymer and two or more transparent layers of a second polymer, wherein the two polymers have different refractive indices and the layers of the first polymer and the layers of the second polymer are arranged in an alternating sequence, and wherein the two polymers are selected from biodegradable polymers.

[0012] Another subject of the present invention is a method for producing effect pigments as described above and below, characterized in that the first polymer and the second polymer are each coextruded, preferably at elevated temperature, superimposed on one another, optionally cut, stacked, and passed through a film die, preferably at elevated temperature, to form a multilayer foil construction, wherein the above steps can also be repeated several times, and wherein preferably after extrusion the polymer foil is not stretched or drawn, the multilayer foil obtained in this way is punched, ground, cut or otherwise comminuted into particles, and the particles are optionally graded according to size.

[0013] Another subject of the invention is a multilayer foil comprising, preferably consisting of, two or more transparent layers of a first polymer and two or more transparent layers of a second polymer as described above and below, wherein the two polymers have different refractive indices and the layers of the first polymer and the layers of the second polymer are arranged in an alternating sequence, the two polymers are selected from biodegradable polymers, and the average single layer thickness of all polymer layers is ≤130 nm.

[0014] Another subject of the present invention is a method for producing a multilayer foil as described above and below, characterized in that the first polymer and the second polymer are each coextruded, preferably at elevated temperature, superimposed on one another, optionally cut, stacked, and passed through a film die, preferably at elevated temperature, to form a multilayer foil construction, wherein the above steps can also be repeated several times, and wherein the polymer foil is preferably not stretched or drawn after extrusion.

[0015] A further subject matter of the present invention is preparations comprising one or more effect pigments according to the invention, in particular products and uses used in this context.

[0016] A further subject of the present invention is the use of the effect pigments, multilayer foils and preparations according to the invention as described above and below, preferably in a product selected from the group consisting of cosmetic products, wash-off products, packaging materials, decorative foils, lacquers, printing inks and plastics.

[0017] A further subject of the present invention is a product comprising one or more effect pigments according to the invention, preparations according to the invention or multilayer foils according to the invention as described above and below, in particular selected from the group consisting of cosmetic products, wash-off products, packaging materials, decorative foils, lacquers, printing inks and plastics.

[0018] According to the EPA Network (European Network of Environmental Protection Agency Plastics Interest Group Leaders, Working Paper November 2018*), the term "biodegradable polymer / plastic" as used herein refers to materials that can potentially be converted into naturally occurring metabolic end products by biological activity (enzymatic cleavage and metabolism by bacteria / fungi). Ideally, this chemical metabolic process results in the mineralization of the plastic into, for example, oxygen, carbon dioxide and its salts, carbon and methane.

[0019] The effect pigments and multilayer foils according to the invention are characterized in particular by angle-dependent color effects, good adhesion of the individual layers and good processing properties. In addition, they contain biodegradable materials from sustainable raw materials, preferably with a proportion of >50% bio-based raw materials, and do not contain inorganic or metal layers, as is the case with effect foils and glitter pigments known and commercially available to date.

[0020] The polymers used in the effect pigments and multilayer foils according to the invention can be extruded, cut and stacked simultaneously without subsequent stretching and exhibit very good adhesion without further auxiliaries. Suitable polymers are commercially available.

[0021] The pigments and multilayer foils according to the invention preferably consist exclusively of organic materials, particularly preferably of biodegradable organic materials, and preferably contain no inorganic materials.

[0022] Both polymers are preferably selected from organic polymers, which may also be cross-linked, and are biodegradable.

[0023] A particularly preferred material combination consists of PLA (polylactic acid, for example made from sustainable corn starch), preferably a copolymer of D- and L-lactic acid monomers, or a PLA blend as the first polymer; and PBAT (polybutylene adipate / terephthalate), preferably in the form of a statistical copolymer as the second polymer. This combination is particularly advantageous because the two copolymers can be coextruded in the same temperature range and their rheological properties, such as viscosity, are well matched.

[0024] Further preferred biodegradable polymers are blends of thermoplastic starch (TPS) with the above or other biodegradable polymers, blends of PBAT with PLA (e.g. the Ecovio series from BASF), Bio-PA6 and Bio-PA11 or polyhydroxy-alkanoates such as polyhydroxybutyrate-co-hydroxyvalerate (PHB / PHV).

[0025] Depending on the selected polymer combination and the refractive index difference Δn between the first polymer and the second polymer (hereinafter also referred to as polymer A and polymer B), the nanoscale polymer layer thickness d 聚合物A / B According to the following equation (1), in principle, the reflection peak λ appears in the wavelength range of λ = 380 to 740 nm. 峰 The optically visible interference effect, where n 聚合物A / B represents the refractive index of polymer A or B, and wherein the polymer film is not drawn or stretched. Only first-order interferences are considered here, since color effects due to second-order interferences are only very weak:

[0026]

[0027] Figure 1 A schematic diagram showing by way of example the generation of interference effects in effect pigments according to the invention and in a multilayer foil having a refractive index n of 1.436 and a layer thickness d A A single layer of polymer A (PLA) with a refractive index n of 1.598 and a layer thickness d B The optically active stacking sequence ABABA of the alternating monolayer of the polymer B (PBAT) of the present invention, wherein the incident light (arrow "a") is reflected at each interface where the refractive index changes and the reflected light wave (arrow "b") interferes. The transmitted light is represented by arrow "c". The multilayer foil is optionally closed with the same polymer layer A or B (here: A) on the front and back sides to achieve the required foil stability. The thickness of these stabilized surface layers is about 8% of the total foil thickness and has only a marginal effect on the interference effect.

[0028] Figure 2 The generation of a visually visible interference effect is shown by way of example, which is produced by the superposition of reflected radiation having a correspondingly suitable reflection wavelength, which depends on the single layer thickness d of the polymer in the effect pigment of the invention and in a multilayer foil having the stacking sequence ABABAB...A (here A serves as a stabilizing surface layer) and the material combination PLA / PBAT.

[0029] By purposeful variation of the thickness of the individual layers, it is thus possible to achieve a desired reflection wavelength and hue for a given refractive index.

[0030] In a preferred embodiment of the present invention, the effect pigments and multilayer foils have an alternating stacking sequence (ABAB...), where A stands for a monolayer of a first polymer (polymer A), B stands for a monolayer of a second polymer (polymer B), and where one of the polymers (polymer A or B) forms the two outer face layers, for example ABABABAB....A or BABAABA....B. The total number of all optically active monolayers of the first polymer and the second polymer in the effect pigments and multilayer foils according to the invention of this preferred embodiment is preferably 7 to 2049, in particular 15 to 1025, particularly preferably 31 to 513, very particularly preferably 63 to 257.

[0031] In another preferred embodiment of the present invention, the effect pigments and multilayer foils have an alternating stacking sequence (ABAB ...), where A represents a monolayer of a first polymer (polymer A) and B represents a monolayer of a second polymer (polymer B), for example ABABAB ... AB. The total number of all optically active monolayers of the first polymer and the second polymer in the effect pigments and multilayer foils according to the invention of this preferred embodiment is preferably 8 to 2048, in particular 16 to 1024, particularly preferably 32 to 512, very particularly preferably 64 to 256.

[0032] The average individual layer thickness of all polymer layers in the effect pigments and multilayer foils according to the invention (ie in each of them) is preferably ≤130 nm, particularly preferably from 40 to 130 nm, very particularly preferably from 60 to 130 nm. 聚合物A and d 聚合物B The respective color effect can be adjusted by a combination of. In practice, the ratio of the layer volumes of the individual layers A and B is varied for this purpose, for example to 25% by volume:75% by volume, 50% by volume:50% by volume or 75% by volume:25% by volume. Deviations in the thickness of the individual layers in the multilayer foil lead to multicolor effects, which can certainly also find application and can be desirable.

[0033] In a particularly preferred embodiment of the invention, the effect pigments and multilayer foils according to the invention have a reflection wavelength in the visible range of the spectrum, in particular in the range from 450 to 750 nm.

[0034] The total thickness of all polymer layers in the effect pigments and multilayer foils according to the invention is preferably from 0.5 to 30 μm, particularly preferably from 1 to 25 μm, very particularly preferably from 4 to 18 μm.

[0035] The refractive index of the first polymer (polymer A) measured at a wavelength of λ = 633 nm is preferably 1.200 to 1.700, particularly preferably 1.300 to 1.600, and very particularly preferably 1.400 to 1.500. The refractive index of the second polymer (polymer B) measured at a wavelength of λ = 633 nm is preferably 1.300 to 1.800, particularly preferably 1.400 to 1.700, and very particularly preferably 1.550 to 1.650. The refractive index of the first polymer (polymer A) is preferably less than the refractive index of the second polymer (polymer B).

[0036] The refractive index difference Δn between the first polymer and the second polymer measured at a wavelength λ=633 nm is preferably 0.001 to 0.800, in particular 0.050 to 0.300, particularly preferably 0.100 to 0.200, very particularly preferably at least 0.140.

[0037] The effect pigments and multilayer foils according to the invention can optionally also be colored or processed with biodegradable dyes, such as liquid dyes (e.g. from the DLC series of the company FARRL) or already colored masterbatches (e.g. from the Fibaplast masterbatch series of the company Finke). However, in a particularly preferred embodiment of the present invention, the effect pigments and multilayer foils according to the invention consist only of a single layer of the first polymer and the second polymer.

[0038] Preferably, the first polymer and the second polymer each have a melting point in the range of 140 to 300° C. Preferably, the difference between the melting points of the first polymer and the second polymer is not more than 60K, particularly preferably not more than 40K.

[0039] Very particular preference is given to polymers or individual layers having a refractive index difference Δn of ≧0.14 (at λ=633 nm), wherein both polymers are preferably processable at the same temperature and have an individual layer thickness of 130 nm or less, in particular 60 to 130 nm.

[0040] In a particularly preferred embodiment of the invention, the individual layer thicknesses of the two polymers are almost identical, ie the ratio of the layer volumes is approximately 50:50.

[0041] The effect pigments according to the invention preferably have a maximum diameter of 1 to 200 μm, particularly preferably 5 to 160 μm, very particularly preferably 10 to 120 μm.

[0042] The effect pigments according to the invention are preferably in the form of flakes. The effect pigments according to the invention preferably have an aspect ratio (shape factor or diameter / thickness ratio) of 1 to 200, particularly preferably 5 to 100, very particularly preferably 6 to 20.

[0043] The effect pigments according to the invention preferably have a regular n-gonal shape, where n=3 to 16, preferably 4 to 8. These or other preferred shapes can be produced in a manner known to the person skilled in the art by using tools or devices which are suitable in each case for comminuting multilayer foils, for example grinding tools.

[0044] The particle size is determined by means of laser diffraction on powders or pigment suspensions using instruments known to the person skilled in the art and commercially available (eg from Malvern, Horiba).

[0045] A further preferred embodiment of the present invention relates to mixtures of two or more effect pigments according to the invention having different hues.

[0046] A further preferred embodiment of the present invention relates to mixtures of two or more effect pigments according to the invention having different particle sizes and / or different hues.

[0047] Preferably, the effect pigments according to the invention have a metallic color effect, particularly preferably gold, copper or silver.

[0048] In a preferred embodiment of the present invention, the method according to the invention for producing effect pigments and multilayer foils comprises the following steps:

[0049] The first polymer and the second polymer are extruded separately, preferably at elevated temperature, overlapped with each other, optionally cut, stacked, and passed through a film die, preferably at elevated temperature, to form a multilayer foil structure. The above steps may also be repeated multiple times.

[0050] Preferably, the polymer foil is not stretched or drawn after extrusion.

[0051] The extrusion is preferably carried out at elevated temperature, in particular at temperatures above 180° C., very particularly preferably at temperatures above 200° C.

[0052] The multilayer foil construction by means of a film die is preferably carried out at elevated temperature, in particular at temperatures > 160° C., very particularly preferably at temperatures > 180° C.

[0053] To produce the effect pigments according to the invention, the multilayer foil thus obtained is subsequently punched, ground, cut or otherwise comminuted into particles, and the particles are optionally fractionated according to size.

[0054] Further suitable process conditions, auxiliaries and apparatus which are not described in detail here, such as extruders, dies for films or grinding tools, are known to the person skilled in the art and are described in the literature.

[0055] A further subject matter of the present invention is the use of the effect pigments, multilayer foils and preparations according to the invention as described above and below, preferably in products selected from the group consisting of cosmetic products, wash-off products, packaging materials, decorative foils, lacquers, printing inks and plastics.

[0056] A further subject matter of the present invention are preparations comprising one or more effect pigments according to the invention, in particular for use in the above-mentioned products and applications.

[0057] A further subject matter of the present invention is a product comprising one or more effect pigments or multilayer foils according to the invention as described above and below.

[0058] The effect pigments according to the invention can be used in a wide variety of ways, for example in products selected from the group consisting of cosmetic products, wash-off products, packaging materials, decorative foils, coatings and lacquers, in particular selected from the group consisting of cosmetic preparations or wash-off preparations, automotive paints, powder paints, printing inks, security printing inks, plastics, ceramic materials, glass, paper, paper coatings, toners for electrophotographic printing processes, seeds, greenhouse foils, tarpaulins, for the preparation of pigment slurries with water, organic and / or aqueous solvents, for the preparation of pigment formulations or dry formulations, for the bulk coloring of foods, for the coating coloring of food products or pharmaceutical products and in valuable documents. The preparation of products of this type is carried out in a manner known to the person skilled in the art.

[0059] The effect pigments according to the invention can be used in cosmetic applications, preferably for example in lipsticks, lip glosses, rouges, eyeliners, eye shadows, (volumizing) mascaras, nail polishes, day creams, night creams, body lotions, cleansing milks, talcum powders, sticks, hair sprays, hair masks, hair dyes, hair conditioners, shampoos, shower gels, shower gels, bath oils, bath additives, sunscreens, make-up, care creams, lotions, soaps, bath salts, toothpastes, facial masks, pressed powders, loose powders and gels, etc. The preparation of products of this type is carried out in a manner known to the person skilled in the art.

[0060] The multilayer foils according to the invention are particularly suitable for use in cosmetic products and as packaging material and decorative foils (also called effect foils) and / or as packaging material and decorative foils.

[0061] For various application purposes, the effect pigments according to the invention can also be used in admixture with other absorbing pigments and / or effect pigments, for example pearlescent pigments, effect pigments, goniochromatic pigments, BiOCl flakes, multilayer pigments, metallic pigments, organic colorants, organic coloring pigments and other pigments, for example transparent and opaque white, colored and black pigments, as well as with flake-shaped iron oxides, holographic pigments, LCPs (liquid crystal polymers) and metal oxide-coated mica and SiO2-based materials. 2 Conventional transparent, colored and black lustrous pigments of flakes, etc. The effect pigments according to the invention can be mixed with commercially available (effect) pigments in any proportions.

[0062] The effect pigments and multilayer foils according to the invention can optionally also be colored with natural colorants.

[0063] Furthermore, in addition to the effect pigments according to the invention, the preparations and products according to the invention may also comprise further components or additives, in particular selected from absorbents, astringents, antimicrobial substances, antioxidants, antiperspirants, defoamers, antidandruff agents, antistatics, adhesives, biological additives, bleaches, sequestrants, deodorants, emollients, emulsifiers, emulsion stabilizers, colorants, wetting agents, film formers, fillers, fragrances, flavorings, insect repellents, preservatives, corrosion inhibitors, cosmetic oils, solvents, oxidants, vegetable ingredients, buffer substances, reducing agents, surfactants, expanding gases, sunscreens, UV filters and UV absorbers, denaturants, viscosity regulators, fragrances and vitamins.

[0064] Even in the absence of additional embodiments, it should be understood that those skilled in the art can make full use of the above description. Therefore, the preferred embodiments and examples should be considered only as illustrative and are not to be considered as limiting disclosures in any way. All starting components are either commercially available or can be synthesized according to known methods. DETAILED DESCRIPTION

[0065] Example 1

[0066] For the preparation of blue effect pigments, PLA was used as polymer A and PBAT was used as polymer B in a volume ratio of 50:50. PLA stands for polylactic acid, and the commercial product used was Ingeo ® 4043, with a refractive index of n = 1.454 (at 633 nm). PBAT stands for polybutylene adipate terephthalate, which is a statistical copolymer of the monomers 1,4-butanediol, adipic acid and terephthalic acid; the commercial product used is Ecoflex from BASF ® F-Blend C1200, with a refractive index of n=1.598 (at 633 nm).

[0067] The two polymers A and B were extruded at 215°C in a coextrusion process, alternately overlapped, i.e. cut and stacked at 215°C, and formed into the final foil shape by a film die at 210°C. This simultaneous processing at the same temperature was possible due to the similar dynamic viscosities of the two polymers in the range of 0.2-0.4 MPa*s. A multilayer foil consisting of a total of 64 individual layers, each with an individual layer thickness of 60 nm, was produced by five cutting / stacking operations.

[0068] The multilayer foil is then cut / punched into particles of the order of 5-200 μm. Pigment particles are obtained which display a blue metallic appearance hue.

[0069] Example 2

[0070] For the preparation of green metallic effect pigments, PLA was used as polymer A and PBAT as polymer B as described in Example 1.

[0071] The two polymers A and B were extruded at 215°C in a coextrusion process, overlapped in turn, cut and stacked at 215°C, and formed into a final foil shape at 210°C by a film die. Due to the similar dynamic viscosity of the two polymers in the range of 0.2-0.4 MPa*s, this simultaneous processing at the same temperature became possible. A total of 128 monolayers were produced by six cutting / stacking operations, with a PLA monolayer thickness of 125 nm and a PBAT monolayer thickness of 115 nm.

[0072] The multilayer foil is then cut / punched into particles of the order of 5-200 μm. Pigment particles are obtained which display a green metallic appearance hue.

[0073] Example 3

[0074] To prepare reddish-gold or copper-colored metallic effect pigments, PLA was used as polymer A and PBAT as polymer B, as described in Example 1.

[0075] The two polymers A and B are extruded at 215°C in a coextrusion process, overlapped in turn, i.e. cut and stacked at 215°C, and formed into a final foil shape at 210°C by a film die. Due to the similar dynamic viscosity of the two polymers in the range of 0.2-0.4 MPa*s, this simultaneous processing at the same temperature becomes possible. A total of 128 monolayers of multilayer foils were produced by six cutting / stacking operations, with a PLA monolayer thickness of 125 nm and a PBAT monolayer thickness of 160 nm.

[0076] The multilayer foil is then cut / punched into particles in the order of 5-200 μm. Pigment particles are obtained which exhibit a copper-gold or copper-colored metallic appearance hue.

[0077] Example 4

[0078] By mixing the green, red and blue metallic-appearing pigment particles prepared according to Examples 1 to 3, a mixture of effect pigments having a silvery luster was obtained.

[0079] The above examples demonstrate that the effect pigments and multilayer foils according to the invention can be produced directly from commercially available biodegradable polymers in a simple and inexpensive manner without further additives or process steps such as stretching etc. and in a wide variety of colors.

[0080] In contrast, commercially available silver-luster glitter pigments, such as 1S Silver or 2S Bright Silver from Moplatec / RJA Plastics GmbH, do not consist of biodegradable material, but are cut from a polymer foil consisting of a PET core which is vacuum-evaporated with aluminum on one side and subsequently provided with an epoxy protective film on both sides.

Claims

1. Effect pigments comprising, preferably consisting of, two or more transparent layers of a first polymer and two or more transparent layers of a second polymer, wherein the two polymers have different refractive indices and the layers of the first polymer and the layers of the second polymer are arranged in an alternating sequence, and wherein the two polymers are selected from biodegradable polymers.

2. The effect pigment according to claim 1, characterized in that The average monolayer thickness of all polymer layers was ≤130 nm.

3. The effect pigment according to claim 1 or 2, characterized in that The first polymer is PLA (polylactic acid) or a PLA blend, and the second polymer is PBAT (polybutylene adipate terephthalate), especially in the form of a statistical copolymer.

4. The effect pigment according to any one or more of claims 1 to 3, characterized in that The average individual layer thickness of all polymer layers is from 40 to 130 nm, particularly preferably from 60 to 130 nm.

5. The effect pigment according to any one or more of claims 1 to 4, characterized in that The total number of all individual layers of the first polymer and the second polymer is 7 to 2049, in particular 15 to 1025, particularly preferably 31 to 513, very particularly preferably 63 to 257.

6. The effect pigment according to any one or more of claims 1 to 5, characterized in that The refractive index of the first polymer at a wavelength λ=633 nm is 1.200 to 1.700, particularly preferably 1.300 to 1.600, very particularly preferably 1.400 to 1.500, and the refractive index of the second polymer (polymer B) at a wavelength λ=633 nm is preferably 1.300 to 1.800, particularly preferably 1.400 to 1.700, very particularly preferably 1.550 to 1.

650.

7. The effect pigment according to any one or more of claims 1 to 6, characterized in that The refractive index difference Δn between the first polymer and the second polymer at a wavelength λ=633 nm is 0.001 to 0.800, in particular 0.050 to 0.300, particularly preferably 0.100 to 0.200, very particularly preferably at least 0.

140.

8. The effect pigment according to any one or more of claims 1 to 7, characterized in that The total thickness of all polymer layers is from 0.5 to 30 μm, particularly preferably from 1 to 25 μm, very particularly preferably from 4 to 18 μm.

9. The effect pigment according to any one or more of claims 1 to 8, characterized in that The effect pigments have a shape factor (diameter / thickness ratio) of 1 to 200, preferably 5 to 100, particularly preferably 6 to 20.

10. Process for producing effect pigments according to any one or more of claims 1 to 9, characterized in that The first polymer and the second polymer are each extruded, preferably at elevated temperature, superimposed on one another, optionally cut, stacked, and passed through a film die, preferably at elevated temperature, to form a multilayer foil construction, wherein the above steps can also be repeated several times, and wherein the polymer foil is preferably not stretched or drawn after extrusion, the multilayer foil thus obtained is punched, ground, cut or otherwise comminuted into particles, and the particles are optionally graded according to size.

11. Preparation comprising one or more effect pigments according to any one or more of claims 1 to 9.

12. Use of the effect pigments according to any one or more of claims 1 to 9 or the preparations according to claim 11 in products selected from the group consisting of cosmetic products, rinse-off products, packaging materials, decorative foils, lacquers, printing inks and plastics.

13. A product selected from the group consisting of cosmetic products, rinse-off products, packaging materials, decorative foils, lacquers, printing inks and plastics, comprising one or more effect pigments according to any one or more of claims 1 to 9 or a preparation according to claim 11.

14. The preparation according to claim 11 or the product according to claim 13, comprising one or more additives selected from the group consisting of binders, effect pigments and absorption pigments.

15. A multilayer foil comprising, preferably consisting of, two or more transparent layers of a first polymer and two or more transparent layers of a second polymer, wherein the layers of the first polymer and the layers of the second polymer are arranged in an alternating sequence, the two polymers being as defined in any one or more of claims 1 to 8, and the average monolayer thickness of all polymer layers being ≤ 130 nm.

16. Method for producing a multilayer foil according to claim 15, characterized in that The first polymer and the second polymer are each extruded, preferably at elevated temperature, superimposed on one another, optionally cut, stacked, and passed through a film die, preferably at elevated temperature, to form a multilayer foil construction, wherein the above steps may also be repeated multiple times, and wherein the polymer foil is preferably not stretched or drawn after extrusion.

17. Use of the multilayer foil according to claim 15 in and / or as packaging material or decorative foil.

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