DE102004039754A1 - Pigments based on cylinders or prisms - Google Patents

Abstract

The present invention relates to cylinders based on cylinders or prisms, wherein the height of the cylinders or prisms is 100 nm to 500 mum and the diameter of the base area of the cylinders or the shortest diagonal of the base of the prisms is 100 nm to 500 mum and the cylinders or prisms of juxtaposed and lying in the direction of the height axis of the cylinder or the prisms tubes and / or rods. Furthermore, the present invention relates to processes for the preparation of these pigments and their use in paints, coatings, printing inks, plastics, films, cosmetic or pharmaceutical formulations, ceramic materials, glasses, paper, for laser marking, in safety materials, in thermal protection, for seed coloring, food coloring , in drug coatings, in dry preparations, in pigment preparations, for analytical purposes, as a switch or as a tracer.

Description

The The present invention relates to cylinder-based pigments or prisms, where the height the cylinder or prisms is 100 nm to 500 μm and the diameter of the Floor space the cylinder or the shortest Diagonal of the base the prisms 100 nm to 500 microns is and the cylinders or prisms are arranged side by side and in the direction of the height axis consist of the cylinder or the prisms lying tubes and / or rods. Furthermore, the present invention relates to methods of preparation these pigments and their use in paints, varnishes, printing inks, plastics, Films, cosmetic or pharmaceutical formulations, ceramic Materials, glasses, Paper, for laser marking, in safety materials, in thermal insulation, for seed coloring, for food coloring, in drug coatings, in Dry preparations, in pigment preparations, for analytical Purposes, as a switch or as a tracer.

The color design everyday objects has always been a big one Importance. Pigments are in addition to the dyes an important fund of the Colorants used for coloring of materials and objects can be used. In many cases, the pigments are inorganic pigments, e.g. White-, Colored or effect pigments. Especially the latter are gaining more and more economic importance, e.g. in automotive paints, powder coatings, in the printing sector or in cosmetics. In addition to the intrinsic color of the effect pigments also play extra Effects such as Gloss, interference phenomena or diffraction phenomena the choice of pigments matter.

Around the requirements of the manufacturers in the above mentioned areas to suffice and to constantly allow new color creations, there is a persistent Need for new pigments. These new pigments should be simple Way to produce, stable, ecological and be toxicologically harmless or chemically inert and should enable special colors and effects in the mentioned applications.

Of the The present invention was therefore based on the object, novel Provide pigments which can be readily prepared.

Surprisingly it has been found that pigments according to the present invention fulfill this requirement profile. The present invention accordingly relates to pigments based on cylinders or prisms, the height of the cylinders or prisms 100 nm to 500 μm is and that the diameter of the base area the cylinder or the shortest Diagonal of the base of the Prisms 100 nm to 500 μm is and the cylinders or prisms are arranged side by side and in the direction of the height axis consist of the cylinder or the prisms lying tubes and / or rods. Furthermore, the subject of the present invention are methods for Production of pigments based on cylinders or prisms as well as the use of the pigments according to the invention in paints, varnishes, Printing inks, plastics, films, cosmetic or pharmaceutical Formulations, ceramic materials, glasses, paper, for laser marking, in safety materials, in thermal insulation, for seed coloring, for food coloring, in drug coatings, in Dry preparations, in pigment preparations, for analytical Purposes, as a switch or as a tracer.

The pigments of the invention are novel alternatives to the previously known pigments and can be used in many ways. Due to the great variability of the microstructure of the pigments and the materials used in the pigments, the pigments can be adapted for the respective application with regard to their optical properties. Thus, by suitable choice of the size dimensions of the tubes and / or rods in relation to the size dimensions of the pigments, suitable pigments can be provided for each wavelength range of the light. For example, by interacting with visible light, the pigments can exhibit color effects which can be advantageously used for everyday use. In many cases, the pigments of the invention show opalescence, which gives the articles a particularly visually appealing appearance. Moreover, with appropriately adapted pigments, an interaction with non-visible radiation, eg UV radiation or infrared radiation, may occur. This interaction can be used as a security feature, since the presence of the pigments of the invention can be detected by irradiation with light of appropriate wavelength. In addition, pigments are toxicologically and ecologically harmless and accessible in the simplest case by methods established in the art. Thus, the pigments can be obtained by the established in the art top-down approach, that is, the structures are very easy to produce macroscopically, for example, by bundling tubes or rods with diameters in the cm range in the desired, arbitrary form. By thermal drawing processes, these systems can then be accurately and reproducibly reduced to structures in the nanometer range. Through this "mechanical nanotechnology" is the one Adjustment, planning and reproducibility much better than the ordered nanostructures produced by conventional methods.

The pigments of the invention are based on cylinders or prisms. The cylinders or prisms may be straight or oblique, preferably straight. If the pigments are those based on prisms, they may have a base area in the form of a polygon V _n with n as the number of corners of the polygon V _n and n ≥ 3. Preferably, n is equal to 3, 4, 5, 6, 7, 8, 9, or 10. The edge lengths of the polygons V _n may be equal or unequal in size, that is, the prisms may be regular or irregular. Preferably, the edge lengths of the polygons V _{n are the} same size, so that they are pigments based on regular prisms.

The height of Prisms or cylinders and thus the length of the pigments can be 100 nm up to 500 μm, Preferably, it is in the range of 5 to 300 microns, and most preferably in the range of 0.5 μm up to 50 μm.

The diameter of the base area of the cylinders or the shortest diagonal of the base area of the prisms can be 100 nm to 500 μm, preferably 2 μm to 200 μm and very particularly preferably 0.5 μm to 70 μm. Ideally, the diagonal of the base of the prisms means the straight line passing through two opposite corners of the polygon V _n . In addition, it is also possible that the diagonal is the line that intersects two opposite edges of the polygon V _n at right angles.

The Prisms or cylinders consist of tubes and / or rods, wherein the prisms or cylinders from an array of at least two tubes and / or rods consist. Preferably, it is a plurality of tubes and / or Bars, where the upper limit of the number per se is not limited. Preferably the prisms and / or cylinders consist of tubes. The tubes can also change the shape of a cylinder or any prism, in the simplest Trap is cylindrical tubes. Here are the geometries the cylinder or prism outer walls of roar and the corresponding inner walls from each other independently. For example, a tube in the form of a prism having a hexagonal geometry with respect to the outside the prism wall a round geometry with respect to the prism inner wall and vice versa. Regarding the There are no individual geometries or individual combinations Restrictions. Preferably, the tubes are prisms with trigonal, tetragonal, hexagonal, octagonal or decagonal, in particular with hexagonal geometry of the base for the outside and with round geometry for the Inside. roar The preferred geometry results in a particularly simple way pigments according to the invention based on prisms with hexagonal base. The surface the tubes and / or bars or the prisms or cylinders can also be structured. The structuring can be arranged, for example, on a regular basis Creases, balls or pyramids are based. Due to the regular structuring take additional produce diffractive effects, as in pigments e.g. from the WO 03/053674 and WO 03/102084 are known, the disclosure of which hereby incorporated by reference.

Of the Difference of the refractive indices between the wall material of the tubes and the tube interior, preferably air, leads to the preferred optical effects of the resulting pigments. The tubes and / or bars can in the form of a densest packing, preferably one hexagonal closest Pack, present. A hexagonal closest packing can be easiest by appropriate packing of hexagonal tube prisms or cylindrical tubes to reach. It can but also targeted flaws are generated, that is individual roar and / or bars can missing in the arrangement. Defects of this kind can be caused by diffraction or interference phenomena cause special color effects. The tubes and / or rods are preferably firmly connected to each other, wherein the compound in particular by an adhesion or by a fusion of the outer walls of the roar and / or bars between each other. In this way, bundles of tubes and / or rods are obtained, which dictate the shape of the prisms or cylinders.

The tubes and / or rods of the cylinders or prisms can be made of glass, SiO ₂ , B ₂ O ₃ , Al ₂ O ₃ , metals, plastics or mixtures of these materials. Alternatively, the cylinders or prisms as well as tubes and / or rods may contain these materials, any combination of materials being conceivable. For example, tubes and / or rods of glass or SiO _{2 may be combined} with tubes and / or rods of metals. The tubes and / or rods are preferably made of glass, SiO ₂ or metals.

The outer diameters of the tubes and / or rods in the pigments according to the invention can vary between 20 nm and 250 μm, preferably between 70 nm and 2 μm and in particular between 90 nm and 800 nm. In the case of tubes, the diameters of the tube walls can be enclosed pores are 1 nm to 2 microns, in particular 20 nm to 1 micron. The distances of the pore centers are in the range of 1.5 nm to 2.5 μm. In addition, the Diameter of the tubes and / or rods or enclosed by the tube walls pores in the pigments be equal or not equal. In this way, the variety of achievable effects can be extended. Pigments of this type can exhibit an interesting play of colors through interference or diffraction effects, which is similar in appearance to that of opals.

Any glass known to those skilled in the art, eg E glass, A glass, E CR glass, C glass, D glass, R glass or S glass, is suitable as the glass. Glasses of these types are known and described, for example, in Ullmann's Encyclopedia of Industrial Chemistry, under Fibers, Synthetic Inorganic, Glass Fibers. In addition to the glasses, SiO _{2 is} also a preferred material. Both the glasses and SiO ₂ may be doped with elements, for example, germanium, gold, silver, platinum, lead, boron, silicon, lanthanides, actinides, trivalent cations of rare earth metals, such as Eu ³⁺ , fluorine and / or phosphorus, there are no restrictions on doping. By doping the glass or SiO ₂ , the refractive properties of the materials can be varied and adapted to the needs.

The Plastics can preferably selected be from the group of polyacrylates, polycarbonates, polystyrenes, Siloxanes, fluoropolymers, polyesters and / or mixtures thereof. Suitable fluoropolymers are, for example, fluoroacrylates, fluoroacrylate esters, fluorinated polyimides, polytetrafluoroethylene or fluorosilicones. Like the glasses can the plastics should be doped with elements, especially the optical ones Properties of plastics vary accordingly.

When Metals for the tubes and / or bars of Cylinders or prisms are for example germanium, gold, Platinum, silver, lead or silicon.

In one embodiment of the present invention, the cylinders or prisms include tubes and / or rods of glass and metals. The tubes and / or rods of metals may be statistically distributed or ordered over the prisms or cylinders. With both variants, additional effects can be achieved, which are based on the reflection of the light at the tubes and / or rods made of metals. In the case of a defined arrangement of tubes and / or rods made of metals, any type of arrangement is included in the present invention. For example, the tubes and / or rods may be made of metals along one or more diagonals of the base of the cylinders or prisms, the diagonals not having to pass through the base center. Ideally, the diagonal of the base of the prisms means the straight line passing through two opposite corners of the polygon V _n . In addition, it is also possible that the diagonal is the line that intersects two opposite edges of the polygon V _n at right angles. The diagonals can be arranged parallel and not parallel to each other. By incorporating tubes and / or rods of metal along one or more diagonals, additional levels acting as mirrors are created which can further increase the gloss and variety of effects. By appropriate arrangement of several diagonals of the desired effect can be achieved regardless of the orientation of the pigment in the application medium.

In a further embodiment, the tubes and / or rods or the resulting bundles thereof may be coated with one or more transparent, semitransparent and / or opaque layers comprising metal oxides, metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures of these materials. The metal oxide, metal oxide hydrate, metal suboxide, metal, metal fluoride, metal nitride, metal oxynitride layers or mixtures thereof may be low (refractive index <1.8) or high refractive index (refractive index ≥ 1.8). Suitable metal oxides and metal oxide hydrates are all metal oxides or metal oxide hydrates known to the person skilled in the art, such as, for example, Example, alumina, alumina hydrate, silica, Siliziumoxidhydrat, iron oxide, tin oxide, cerium oxide, zinc oxide, zirconium oxide, chromium oxide, titanium oxide, in particular titanium dioxide, titanium oxide and mixtures thereof, such as ilmenite or pseudobrookite. As metal suboxides, for example, the titanium suboxides can be used. Chromium, aluminum, nickel, silver, gold, platinum, lead, germanium, titanium, copper or alloys are suitable metals, for example, magnesium fluoride is suitable as the metal fluoride. As metal nitrides or metal oxynitrides, for example, the nitrides or oxynitrides of the metals titanium, zirconium and / or tantalum can be used. Preference is given to applying metal oxide, metal, metal fluoride and / or metal oxide hydrate layers and very particularly preferably metal oxide and / or metal oxide hydrate layers to the tubes and / or rods. Furthermore, multi-layer constructions of high-refractive and low-refractive index metal oxide, metal oxide hydrate, metal or metal fluoride layers can also be present, alternating preferably high and low refractive index layers. Particularly preferred are layer packages of a high and a low-refractive layer, wherein one or more of these layer packages can be applied to the tubes and / or rods. The order of the high and low refractive layers can be adapted to the material of the tubes and / or rods, to include the tubes and / or rods in the multi-layer structure. In another embodiment, the metal oxide, metal oxide hydrate, metal suboxide, metal, metal fluoride, metal nitride, metal oxynitride layers or mixtures thereof be added or doped with colorants and / or other elements. Suitable colorants or other elements are, for example, organic or inorganic color pigments such as colored metal oxides, eg magnetite, chromium oxide or color pigments such as Berlin Blue, ultramarine, bismuth vanadate, thenard blue, or organic color pigments such as indigo, azo pigments, phthalocyanines or carmine red or elements such as yttrium or antimony. Tubular and / or rod-based pigments containing these layers exhibit a high color diversity with respect to their body color and, in many cases, can show an angle-dependent change of color (color flop) due to interference.

The outer layer on the tubes and / or rods in a preferred embodiment is a high refractive index metal oxide. This outer layer may additionally be part of a layer package on the abovementioned layer packages or, for high-index carriers, for example of TiO ₂ , titanium suboxides, Fe ₂ O ₃ , SnO ₂ , ZnO, ZrO ₂ , Ce ₂ O ₃ , CoO, Co ₃ O ₄ , V ₂ O ₅ , Cr ₂ O ₃ and / or mixtures thereof, such as ilmenite or pseudobrookite exist. TiO ₂ is particularly preferred.

in the Trap of tubes can these closed or open at the prism or cylinder bases, preferably be closed so that solvents or other compounds when incorporated in formulations or applications not in the roar can penetrate. That way, it's going to be a change the refractive index differences between the tube materials and the in trapped in the tubes Component, e.g. Air, prevented. This ensures an unchanged color and effect design when incorporated in the appropriate application systems.

However, the cavities between the rods and / or tubes or in the tubes can also be filled with any substances, the degree of filling need not be complete. The infiltration or impregnation of the cavities with substances can be carried out from the gas phase or in solution or dispersion. The cavities may be infiltrated, for example, from the gas phase with vapors of metals or gaseous precursors for metals, semiconductors (eg III-V semiconductors such as GaN, AlN, InN or mixed crystals thereof, GaAs, InAs, InP) or insulators. Furthermore, the cavities can be filled by means of solution impregnation by utilizing capillary effects, for example with dispersed nanoparticles or soluble precursors for metals, semiconductors or insulators. A filling of the cavities with phosphors is likewise conceivable, for example with Eu ³⁺ : Y ₂ O ₃ , wherein the absorption and emission properties of the phosphors can be influenced by the modulated difference of the refractive index of the arrangement of the tubes and / or rods. In addition, the cavities can be loaded with dyes, for example with laser-active dyes for the construction of microlasers. Suitable dyes are known in the art and can be used in the context of the present invention. In addition, the cavities can be loaded with liquid crystalline mixtures. As a result, the optical properties can be influenced by external influences, such as by changing the temperature or by the influence of electrical or magnetic fields. For example, it is possible to realize pigments for switchable paints in which the wavelength of the reflection colors can be shifted or the transparency can be changed by the influence of external electric fields.

In a further embodiment of the present invention the pigments additionally with one or more transparent, semi-transparent and / or opaque Layers containing metal oxides, metal oxide hydrates, metal suboxides, Metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures These materials may be coated, with one or more containing transparent, semi-transparent and / or opaque layers Metal oxides, metal oxide hydrates, metal suboxides, metals, metal fluorides, Metal nitrides, metal oxynitrides and / or mixtures of these materials can be doped with colorants and / or elements. Examples and arrangement options for the The above materials are already mentioned in advance.

Farther can the pigments of the invention be provided with a secondary coating. As material for the secondary coating For example, organosilanes and / or polymers are suitable the materials mentioned mixed in a layer or separately can be present in several layers.

X

= OH, Halogen, Alkoxy, Aryloxy

Z

= Si

R

= Alkyl, Phenyl oder Wasserstoff

B

= organische, zumindest bifunktionelle Gruppe (Alkylen, Alkylenoxyalkylen)

Y

= Alkyl-, Amino-, substituierte Amino-, Hydroxy-, Hydroxyalkyl-, Siloxan-, Acetoxy, Isocyanat-, Vinyl-, Acryloyl-, Epoxy-, Epoxypropyloxy-, Imidazol- oder Ureidogruppe

n, m

= 0,1,2,3 mit n + m ≤ 3 bestehen.

Suitable organosilanes are, for example, silanes of the general formula X _4-n ZR _nm (-BY) _m With

X

= OH, halogen, alkoxy, aryloxy

Z

= Si

R

= Alkyl, phenyl or hydrogen

B

= organic, at least bifunctional group (alkylene, alkyleneoxyalkylene)

Y

= Alkyl, amino, substituted amino, hydroxy, hydroxyalkyl, siloxane, acetoxy, isocyanate, vinyl, acryloyl, epoxy, epoxypropyloxy, imidazole or ureido group

n, m

= 0,1,2,3 with n + m ≤ 3.

The organosilanes consist of an anchor group (X _{4 nm} Z), which can bind to the surface of the pigment, for example, at least one hydrophobic group (R, B) and one or more alkyl or functional groups (Y). Preferably, the anchor group consists of alkoxysilanes, which can be converted by hydrolytic reaction conditions into corresponding hydroxyl groups.

By the choice of suitable functional groups, the organosilane the Requirements are adjusted. In addition, depending by coating order, by reaction of the functional Groups with corresponding functionalities in the application media additional Bonds between pigment and medium via the organosilane produced become. In a particular embodiment becomes the surface the particles of the invention with a combination of organic adapted to the feed functionalities modified. For this purpose, the use of mixtures is also suitable different organosilanes. The hydrophobicity of the particle surface can by integration of alkyl-containing coupling reagents, e.g. Alkyl silanes, also be adapted. In addition to the organosilanes is also the use of their hydrolysates and their homogeneous and heterogeneous oligomers and / or polymers are preferred, which also alone or in combination with the silanes already described can be used. Particular preference is given to mixtures of different organosilanes, in particular with mutually different functional groups Y, whose use ensures a special scope.

Examples of organosilanes are propyltrimethoxysilane, propyltriethoxysilane, isobutyltrimethoxysilane, n-octyltrimethoxysilane, i-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, vinyltrimethoxysilane, octadecyltrimethoxysilane, preferably vinyltrimethoxysilane. Suitable oligomeric, alcohol-free organosilane are, among others, those sold under the trade name "Dynasylan ^®" by the company. Sivento products, such. As Dynasylan HS 2926, Dynasylan HS 2909, Dynasylan HS2907, Dynasylan NS 2781, Dynasylan NS 2776, Dynasylan NS 2627. In addition, oligomeric vinylsilane and aminosilane hydrolyzate are suitable as organic coating.Functionalized organosilanes are, for example, 3-aminopropyltrimethoxysilane, 3-methacryloxytrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, beta- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane, gamma-isocyanatopropyltrimethoxysilane, 1, 3-bis (3-glycidoxypropyl) -1,1,3,3-tetramethyldisiloxane, ureidopropyltriethoxysilane, preferred are 3-aminopropyltrimethoxysilane, 3-methacryloxytrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, beta- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane, gamma- Isocyanatopropyltrimethoxysilane Examples of polymeric silane systems are described in WO 98/13426 and are described, for example, in US Pat B. sold by the company. Sivento under the trademark Hydrosil ^® .

The Polymers can e.g. selected from the group of polyethers, polyesters, polyacrylates, polyvinylcaprolactams, Cellulose, polystyrenes, polyvinyl alcohols, polyvinyl acetates, polysiloxanes, derivatives the said polymers or mixtures thereof. Preferably if the polymers are crosslinked melamine-formaldehyde resins, LCST and / or UCST polymers or polymers with solvolyzable groups. The crosslinked melamine-formaldehyde resins are formed by depositing crosslinking melamine-formaldehyde resins the pigments and then curing or Crosslinking of the melamine-formaldehyde resins formed. Further examples and embodiments This method can be found in WO 03/074614.

LCST polymers or UCST polymers are polymers that are at low or high temperatures in a solvent soluble are and when raising or Lowering the temperature and reaching the so-called LCST or UCST (lower or upper critical solution temperature) from the solution as separated separate phase. Such polymers are e.g. in the literature in "Polymere", H.G. Elias, Hüthig and Wepf-Verlag, Zug, 1996 on pages 183 ff. Described. Both Polymers with solvolyzable groups become these during solvolysis split off, wherein the polymer precipitates on the substrate.

suitable LCST polymers for The present invention are, for example, those described in the WO 01/60926 and WO 03/014229 are described. Particularly suitable LCST polymers are polyalkylene oxide derivatives, preferably polyethylene oxide (PEO) -Derivatet, polypropylene oxide (PPO) derivatives, olefinic modified PPO-PEO block Copopolymere, with acrylate-modified PEO-PPO-PEO triblock copolymers, and polymers or their Derivatives of the class of polymethyl vinyl ethers, poly-N-vinylcaprolactams, ethyl- (hydroxyethyl) -celluloses, poly- (N-isopropylacrylamide) as well as polysiloxanes. Particularly preferred LCST polymers are with olefinic or silanolic groups modified siloxane polymers or polyether.

suitable In particular, UCST polymers are polystyrene, polystyrene copolymers and polyethylene oxide copolymers.

Preference is given to using LCST or UCST polymers with solvolyzable or functional groups which have strong interactions and / or chemical bonds with the substrate or the application medium, such as the paint matrix, can enter. All functional groups known to those skilled in the art are suitable, in particular silanol, amino, hydroxyl, olefin, hydroxyl, epoxy, acid anhydride and acid groups.

The LCST or UCST polymers preferably have molecular weights in the range from 300 to 500,000 g / mol, in particular from 500 to 20,000 g / mol.

The Postcoats can in addition also Additives containing the chemical and / or mechanical stability of the pigments additionally increase or lower or the pigments UV-filtering properties or give a coloring effect. Suitable additives are e.g. Nanoparticles of all kinds, plasticizers, antioxidants, radical scavengers, UV filters, dyes, Microtitanium or mixtures thereof. The additives become the solution of Polymers preferably mixed as a dispersion, with preference the same solvent like that of the polymer solution is used. By the inclusion of foreign matter, such as Nanoparticles, plasticizers or dyes can change the properties of the pigments the individual needs be adapted by the user, or it can be several functionalities, such as e.g. Coloring and UV filters, together in one kind pigment be combined.

The pigments of the invention are easily accessible. Thus, methods for preparing the pigments of the invention also the subject of the present invention.

• a) Anordnen von Röhren und/oder Stäben in Form von Zylindern oder Prismen,
• b) Thermisches Ziehen der in a) erhaltenen Zylinder oder Prismen, so dass der Durchmesser der Grundfläche der Zylinder oder die kürzeste Diagonale der Grundfläche der Prismen 100 nm bis 500 μm beträgt und
• c) Zerkleinern der in b) erhaltenen Zylinder oder Prismen, so dass die Höhe der Zylinder oder Prismen 100 nm bis 500 μm beträgt.

An embodiment of the method according to the invention comprises the following method steps:

• a) arranging tubes and / or rods in the form of cylinders or prisms,
• b) thermally drawing the cylinders or prisms obtained in a) such that the diameter of the base area of the cylinders or the shortest diagonal of the base area of the prisms is 100 nm to 500 μm, and
• c) crushing the cylinders or prisms obtained in b) so that the height of the cylinders or prisms is 100 nm to 500 μm.

The cylinders or prisms obtained in process steps a) and b) may in the simplest case be so-called photonic crystal fibers. Materials of this kind are known and methods for the preparation of photonic crystal fibers have been described many times, eg in WO 00/49436, EP 1 234 806 WO 03/012500, WO 02/101430, WO 03/086738, US 2002/0031319 or US 2003/0056550, the disclosure contents of which are hereby incorporated by reference in this application. The process variants mentioned in the individual disclosures, for example for the thermal drawing of the cylinders or prisms, can likewise be used in the processes according to the invention.

In a further embodiment the inventive method be according to process step a) cylinders or prisms containing tubes and / or rods of glass and metal and made according to the above mentioned process steps b) and c) processed. Here, the Tubes and / or Bars out Metal randomly distributed or arranged over the cylinders or prisms are distributed, preferably along one or more diagonals the base area the cylinder or prisms arranged. Through the processing steps b) and c), these structure patterns are scaled down accordingly and can be found in the pigments thus prepared again.

In a further embodiment the inventive method become the tubes and / or Bars or the resulting bundles in advance with one or more transparent, semitransparent and / or opaque layers containing metal oxides, metal oxide hydrates, metal suboxides, metals, Metal fluorides, metal nitrides, metal oxynitrides or mixtures coated with these materials. Corresponding materials are already mentioned in the description of the pigments according to the invention. The coating may be prepared by any method known to those skilled in the art, e.g. wet chemical, by hydrolytic decomposition of suitable precursors or by CVD or PVD.

Furthermore can in a further embodiment the method of the invention Pigments with one or more transparent, semitransparent and / or opaque layers containing metal oxides, metal oxide hydrates, Metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures of these materials. suitable Materials and processes for their production are already in advance called.

Farther can the pigments in a further embodiment of the method according to the invention be provided with a secondary coating. Suitable post-coatings are already mentioned in the description of the pigments according to the invention. The application of the post-coating can after all the expert known methods, e.g. by precipitation in solution, by application in the melt, by solvolysis or by polymerizations on the surface.

The comminution mentioned in process step c) can also be carried out by conventional methods conditions, eg by grinding, cutting and / or chopping. Process variants of this type and suitable apparatuses are for example made of US 4,319,506 , US 2003/0231845, WO 02/42814, EP 0 229 500 . EP 0 640 570 . EP 0 563 687 or WO 03/097543. In the simplest case, the crushing is done by a hot cleaver, which splits the prisms or cylinders by melting. Furthermore, the crushing can also be done with a laser cutting beam.

Farther can the tubes be closed at the prism or cylinder bases. The close the tubes may be by melting, capping, grafting and / or by polymerization reactions respectively. In the simplest case, the closing is done by Melting the tube ends, this being the same time in the process of crushing or can be done separately in a separate step. Other process variants include capping, grafting or stuffing the tubes at the ends, e.g. with polymerizable compounds attached to the tube ends by polymerization a solid bond with the tube ends received. Examples of this can be found inter alia in US 2003/0068150, the disclosure thereof hereby incorporated by reference.

In a further embodiment the inventive method can the cavities between the bars and / or tubes or in the tubes filled with substances become. This can be done later Infiltrating or impregnating over the Gas phase or by solution or dispersion loading carried out. Examples of suitable substances are already mentioned in advance.

The pigments of the invention Due to their advantageous properties, they are suitable for a large bandwidth of applications. The invention is therefore also the use of pigments of the invention in paints, varnishes, printing inks, plastics, foils, cosmetic or pharmaceutical formulations, ceramic materials, glasses, paper, for laser marking, in safety materials, in thermal insulation, for Coloring seed, for food coloring, in Drug coatings, in Dry preparations, in pigment preparations, for analytical Purposes, as a switch or as a tracer.

in the In the case of cosmetic formulations, the pigments according to the invention are suitable especially for Products and formulations of decorative cosmetics, e.g. Nail polishes coloring powders, lipsticks or eyeshadows, soaps, toothpastes etc. Of course can the pigments of the invention in the formulations also with any kind of cosmetic raw and Excipients are combined. These include u.a. Oils, fats, waxes, film formers, Preservatives and general application properties determining adjuvants, e.g. Thickener and rheological additives such as bentonites, hectorites, silica, ca silicates, gelatin, high molecular weight carbohydrates and / or surface-active adjuvants, etc. The pigments of the invention containing formulations belong to the lipophilic, hydrophilic or hydrophobic type. In heterogeneous Formulations with discrete aqueous and non-aqueous Phases can the pigments of the invention in each case contain only one of the two phases or over both Be distributed phases.

The pH values of the formulations may vary between 1 and 14, preferably between 2 and 11 and more preferably between 5 and 8 are. The concentrations of the interference pigments according to the invention There are no limits in the formulation. You can - depending on Use case - between 0.001 (rinse-off products, e.g., shower gels) - 100% (e.g., gloss effect article for special Applications) are. The pigments according to the invention can furthermore can also be combined with cosmetic active ingredients. Suitable active ingredients are e.g. Insect Repellents, UV A / BC protection filters (e.g., OMC, B3, MBC), Anti-aging agents, Vitamins and their derivatives (e.g., vitamins A, C, E, etc.), self-tanner (e.g. DHA, eryosterose et al.) As well as other cosmetic active ingredients such as e.g. Bisabolol, LPO, ectoine, emblica, allantoin, bioflavanoids and their derivatives.

at Use of pigments in paints and coatings are all the expert known applications possible, such as. Powder coatings, automotive coatings, printing inks for the deep, Offset, screen or flexo printing, as well as for coatings in outdoor applications. For the Production of printing inks is a variety of binders, in particular water-soluble types, suitable, e.g. based on acrylates, methacrylates, polyesters, Polyurethanes, nitrocellulose, ethylcellulose, polyamide, polyvinyl butyrate, phenolic resins, Maleic resins, starch or polyvinyl alcohol. The paints may be water or solvent-based Paints act, the selection of paint components the general knowledge of Professional is subject. The pigments, if they are for example liquid crystalline Substances in their cavities included, for switchable paints, e.g. For Automotive applications are used. It will be the simplest Trap built an electric field, with the sheet metal body as an electrode and a conductive one Coating, e.g. an ITO particle-containing layer as a counter electrode. Alternatively, the activation of the liquid-crystalline substances also done by the ambient temperature.

Furthermore can the pigments of the invention used for the pigmentation of films and plastics, e.g. For Agricultural films, infrared-reflective films and discs, gift foils, Plastic containers and moldings for all that Specialist known applications. As plastics, all are suitable common Plastics for the incorporation of the shaped bodies according to the invention, e.g. Duromers or thermoplastic Plastics. The description of the applications and the applicable Plastics, processing methods and additives can be found e.g. in RD 472005 or in R. Glausch, M. Kieser, R. Maisch, G. Pfaff, J. Weitzel, pearlescent pigments, Curt R. Vincentz Verlag, 1996, 83 ff., the disclosure content of which is included here.

Because of the special angle-dependent color effects in combination with the background, body or luminescent color pigments of the invention are also suitable for use in security applications, such as security printing and security features for example forgery-proof cards and ID cards, such as tickets, identity cards, Banknotes, checks and check cards as well as other forgery-proof documents. In the field of agriculture, the pigments can be used to color seed and other primary products, and also in the food industry for pigmenting foods. For pigmenting coatings in medicaments such as tablets or dragees, the pigments according to the invention are also usable, such as in DE 198 31 869 or US 6,627,212 described.

Farther the pigments of the invention are suitable for use in switchable systems, in particular when the cavities between the bars and / or in the tubes with substances, e.g. liquid crystalline Substances are filled. By the action of external influences, e.g. electric fields leaves control the transparency and / or the reflectivity in this way.

In addition, the pigments obtained according to the present invention are suitable for analytical purposes, for example in microanalysis or sensor systems. Thus, it is conceivable that the specific analyte changes the refractive index contrast by entering the pores. This leads to a change in the optical properties which can be detected. In this case, for example when SiO _{2 is selected} as the pigment material, it is also conceivable to dock special functional groups on the silanol-containing surface in the cavities, which makes possible a specific detection.

The pigments of the invention are also suitable for use in blends with organic and / or inorganic colorants, for example organic or inorganic dyes and / or pigments, such as transparent and opaque white, colored and black pigments as well as platelet-shaped iron oxides, organic pigments, holographic pigments , LCPs (Liquid Crystal Polymers) and conventional transparent, colored and black luster pigments on the basis of metal oxide-coated platelets based on mica, metal, glass, Al ₂ O ₃ , Fe ₂ O ₃ , SiO ₂ , etc. The pigments according to the invention can be used in any ratio with commercial pigments and fillers.

When fillers are e.g. naturally and synthetic mica, nylon powder, pure or filled melanin resins, Talcum, glasses, Kaolin, oxides or hydroxides of aluminum, magnesium, calcium, zinc, BiOCl, barium sulfate, calcium sulfate, calcium carbonate, magnesium carbonate, Carbon, as well as physical or chemical combinations of these substances to call. In terms of the particle shape of the filler there are no restrictions. It can meet the requirements according to e.g. platy, spherical or acicular be.

The pigments of the invention are also suitable for the preparation of flowable pigment preparations and dry preparations containing one or more pigments according to the invention, binders and optionally one or more additives. Among dry preparations are also preparations to understand the 0 to 8 wt .-%, preferably 2 to 8 wt .-%, in particular 3 to 6 wt .-%, of water and / or a solvent or solvent mixture contain. The dry preparations are preferably as pellets, granules, chips, sausages or Briquettes and have particle sizes of 0.2-80 mm. Find the dry preparations in particular application in the production of printing inks and in cosmetic formulations.

A special application the pigments of the invention consists in its use as a tracer in mixtures with other organic and / or inorganic colorants. Tracers are used in modern products widely used as identification means. With your help the authenticity of a product should be proven or the origin of a product are reconstructed. Common tracers are based on fluorescent, radioactive or luminescent substances that are to be protected Product may be added as a powder, suspension or liquid. These substances are often toxicologically and environmentally questionable or need for their traceability special equipment and devices.

The pigments according to the invention can be used to prepare the colorants to be marked or from them products, such as paints, powders, paints or suspensions, using all methods known to those skilled in the art. The proportion of the tracer in the product to be labeled is usually ≦ 5 wt .-%, based on the labeled product and preferably <2 wt .-% and most preferably 0.1-1 wt .-%.

ever according to the size of the pigments of the invention the tracer in the mixtures can very easily by means of a microscope or detected with the scanning electron microscope. Chemically and toxicologically, these tracers, e.g. effect pigments and are thus chemically inert and toxicologically harmless. The pigments of the invention can be added in very small doses, so that the coloristics in the application so that it is not significantly affected. As for this Application to the customer requirements specifically matched pigments of the invention are not commercially available available are sufficient copy protection of the mixture to be marked guaranteed.

The pigments of the invention can be because of the stability and the chemically inert character easily and easily and process in the above applications or formulations. Paints, lacquers, printing inks, plastics, films, cosmetic or pharmaceutical formulations, ceramic materials, glasses, paper, Safety materials, seeds, food, pharmaceuticals, analyzer systems, Switches, dry preparations or pigment preparations containing the pigments of the invention are accordingly also subject of this invention.

Claims (35)

Pigments based on cylinders or prisms, characterized in that the height of the cylinders or prisms is 100 nm to 500 μm and that the diameter of the base of the cylinders or the shortest diagonal of the base of the prisms is 100 nm to 500 μm and the cylinders or prisms of juxtaposed and lying in the direction of the height axis of the cylinder or the prisms tubes and / or rods. Pigments according to claim 1, characterized in that the prisms have a base area in the form of a polygon V _n with n as the number of corners of the polygon V _n and n ≥ 3. Pigments according to claim 2, characterized in that n = 3, 4, 5, 6, 7, 8, 9 or 10 is. Pigments according to one of claims 2 or 3, characterized in that the edge lengths of the polygons V _{n are} equal or unequal in size. Pigments according to one the claims 1 to 4, characterized in that the cylinders or prisms straight or inclined cylinders or prisms are. Pigments according to one the claims 1 to 5, characterized in that the surface of the tubes and / or rods or the prisms or cylinders is structured. Pigments according to one of Claims 1 to 6, characterized in that the tubes and / or rods of the cylinders or prisms are made of glass, SiO ₂ , B ₂ O ₃ , Al ₂ O ₃ , metals, plastics or mixtures of these materials, or the cylinders or prisms as well as tubes and / or rods contain these materials. Pigments according to claim 7, characterized in that the cylinders or prisms tubes and / or Bars out Glass and metals included. Pigments according to claim 7 or 8, characterized that the metal is germanium, gold, platinum, silver, lead or silicon is. Pigments according to claim 8, characterized in that the tubes and / or rods of metals along one or more diagonals of the base of the cylinder or prisms lie. Pigments according to one the claims 7 to 10, characterized in that the tubes and / or rods or the resulting bundles with one or more transparent, semitransparent and / or opaque layers containing metal oxides, metal oxide hydrates, metal suboxides, Metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures these materials are coated. Pigments according to claim 11, characterized in that the one or more transparent, semitransparent and / or opaque layers containing metal oxides, Metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides and / or mixtures of these materials with colorants and / or Elements are doped. Pigments according to one the claims 1 to 12, characterized in that the tubes and / or rods outside diameter of 40 nm and 250 μm exhibit. Pigments according to one the claims 1 to 13, characterized in that the diameters of the tubes and / or Bars or the one enclosed by the tube walls Pores in the pigments are the same size or unequal size. Pigments according to one the claims 1 to 14, characterized in that the pigments additionally with one or more transparent, semi-transparent and / or opaque Layers containing metal oxides, metal oxide hydrates, metal suboxides, metals, Metal fluorides, metal nitrides, metal oxynitrides or mixtures these materials are coated. Pigments according to claim 15, characterized in that the one or more transparent, semitransparent and / or opaque layers containing metal oxides, Metal oxide hydrates, metal suboxides, metals, metal fluorides, metal nitrides, metal oxynitrides and / or mixtures of these materials with colorants and / or Elements are doped. Pigments according to one the claims 1 to 16, characterized in that the tubes are closed at the prism or cylinder base surfaces. Pigments according to one the claims 1 to 17, characterized in that the cavities between the rods and / or roar or in the tubes filled with substances are. Pigments according to one the claims 1 to 18, characterized in that the pigments with a secondary coating are provided. Pigments according to claim 19, characterized in that the post-coating of organosilanes and / or polymers. Process for the preparation of pigments according to claim 1, comprising the method steps a) arranging tubes and / or rods in the form of cylinders or prisms, b) Thermal pulling the in a) obtained cylinder or prisms, so that the diameter the base area the cylinder or the shortest Diagonal of the base the prisms 100 nm to 500 microns is and c) Grinding the cylinders or prisms obtained in b), so that the height the cylinder or prisms is 100 nm to 500 μm. Method according to claim 21, characterized in that it is in the process steps a) and b) obtained cylinders or prisms to Photonic Crystal Fibers acts. A method according to claim 21, characterized in that the tubes and / or rods of the cylinders or prisms made of glass, SiO ₂ , B ₂ O ₃ , Al ₂ O ₃ , metals, plastics or mixtures of these materials or that the cylinders or prisms Tubes and / or rods of these materials included. Method according to claim 23, characterized in that the cylinders or prisms tubes and / or Bars out Glass and metals included. Method according to claim 24, characterized in that the tubes and / or rods of metals along one or more diagonals of the base of the cylinder or prisms to be ordered. Method according to one the claims 21 to 25, characterized in that the tubes and / or rods or the resulting bundles in advance with one or more transparent, semitransparent and / or opaque layers containing metal oxides, metal oxide hydrates, metal suboxides, metals, Metal fluorides, metal nitrides, metal oxynitrides or mixtures these materials are coated. Method according to one the claims 21 to 26, characterized in that the pigments additionally with one or more transparent, semi-transparent and / or opaque Layers containing metal oxides, metal oxide hydrates, metal suboxides, Metals, metal fluorides, metal nitrides, metal oxynitrides or mixtures these materials are coated. Method according to one the claims 21 to 27, characterized in that the pigments with a secondary coating be provided. Method according to one the claims 21 to 28, characterized in that the comminution by grinding, Cutting and / or chopping takes place. Method according to one the claims 21 to 29, characterized in that the tubes closed at the prism or cylinder base surfaces become. Method according to claim 30, characterized in that the closing by melting, capping, Grafting and / or carried out by polymerization reactions. Method according to one the claims 21 to 31, characterized in that the cavities between the bars and / or tubes or in the tubes filled with substances become. Use of pigments according to Claim 1 in paints, lacquers, printing inks, plastics, films, cosmetic or pharmaceutical formulations, ceramic materials, glasses, paper, for laser marking, in security materials, in thermal protection, for seed coloring, for food coloring, in pharmaceutical coatings, in Dry preparations, in pigment preparations, for analytical purposes, as a switch or as a tracer. Use according to claim 33, characterized in that the pigments with organic and / or inorganic colorants are mixed. Paints, varnishes, printing inks, plastics, films, cosmetic or pharmaceutical formulations, ceramic materials, glasses, Paper, Safety Materials, Seed, Food, Medicines, Analysis systems, switches, dry preparations or pigment preparations containing one or more pigments according to claim 1.