Abstract: The present invention relates to a method of producing cancer stem cells that comprises culturing a living cell population containing cancer cells in the presence of a gel substance to obtain a living cell population containing cancer stem cells, wherein the gel substance is a material that induces expression of osteopontin in at least a portion of cells contained in the living cell population. Moreover, the present invention relates to an agent for inducing conversion of cancer cells to cancer stem cells that comprises a gel substance that induces expression of osteopontin in at least a portion of the cells contained in a living cell population. The gel substance is a synthetic polymer gel composed of, for example, double network gel, PNaSS gel, PCDME gel, PA gel, RAMPS gel, PDMA gel or PAAc gel. The present invention provides means and a method that enable the preparation of cancer stem cells in a relatively short period of time and at a relatively low culturing cost without requiring expensive equipment.

Abstract: An electromagnetic interference (EMI) shielded device which includes an object to be shielded and an EMI shielding material encompassing the object. The EMI shielding material is made up of, but not limited to a broadband biopolymer or polymer dissolved in organic solvents and shielding guest material. The specific makeup of the shielding material and fabrication procedure of the shielding material is also included herein.

Abstract: The application provides a sintering apparatus, a packaging system for an organic light emitting diode device and a sintering method, belongs to the technical field of organic light emitting diode device and can solve problems of long process time and high cost existed in the existing high temperature sintering process of organic light emitting diode device. The sintering apparatus comprises two sintering chambers capable of being communicated with each other, during operation, the substrate coated with glass cement is first placed into a sealed first sintering chamber to complete a first sintering process; then the substrate is placed into the second sintering chamber to complete a second sintering process. Thus, a time interval between the first sintering process and the second sintering process can be reduced, and no more nitrogen is wasted in transition from the first sintering process to the second sintering process.

Abstract: To provide a rare earth magnet having excellent coercive force and a production method thereof. A rare earth magnet, wherein the rare earth magnet comprises a magnetic phase containing Sm, Fe, and N, a Zn phase present around the magnetic phase, and an intermediate phase present between the magnetic phase and the Zn phase, wherein the intermediate phase contains Zn and the oxygen content of the intermediate phase is higher than the oxygen content of the Zn phase; and a method for producing a rare earth magnet, including mixing a magnetic raw material powder having an oxygen content of 1.0 mass % or less and an improving agent powder containing metallic Zn and/or a Zn alloy, and heat-treating the mixed powder.

Abstract: The present disclosure provides a method for preparing inorganic nanoparticle-gelatin core-shell composite nanoparticles, comprising: dissolving gelatin in a aqueous solution (in which inorganic nanoparticles are dispersed in) to obtain the gelatin-contained aqueous solution, dropwise adding a polar organic solvent to obtain a suspension of inorganic nanoparticle-gelatin core-shell composite particles of nanometer size or submicrometer size, then adding a cross-linking agent thereto to cross-link the gelatin components of the composite particles, followed by washing step to finally obtain inorganic nanoparticle-gelatin core-shell composite micro/nano-particles with inorganic nanoparticles as the core and gelatin as the shell.

Abstract: Provided is an ?-iron oxide type ferromagnetic powder with a ratio Hc173K/Hc296K between a coercive force Hc173K measured at a temperature of 173 K and a coercive force Hc296K measured at a temperature of 296 K is higher than 1.00 and less than 2.00, and a magnetic recording medium containing the ?-iron oxide type ferromagnetic powder in a magnetic layer.

Abstract: Disclosed are a microneedle, an apparatus for manufacturing a microneedle including a support part containing a medicinal solution for coating a microneedle, a controller for controlling the temperature of the medicinal solution contained in the support part, and a dryer for drying the medicinal solution coated on the microneedle, and a method of manufacturing the microneedle using the apparatus. According to the configuration, the temperature of the medicinal solution can be adjusted such that a viscosity suitable for coating with the medicinal solution is maintained, whereby the quality of a microneedle coated with the medicinal solution can be improved, and denaturation of active ingredients in the medicinal solution can be prevented, which causes stability increase.

Abstract: Embodiments of the present disclosure disclose an evaporating device and an evaporating method. The evaporating device comprises: a Halbach magnet array and a mask setting region. A magnetization direction of at least part of the Halbach magnet array precesses clockwise or counter-clockwise, so that magnetic fields having different magnetic fields are formed at two sides of the Halbach magnet array; and the mask setting region is disposed within the magnetic field at one side of the Halbach magnet array. The mask of the ferromagnetic material is placed in the evaporating device provided by the embodiments of the present disclosure. The mask is subject to an attractive force of the Halbach magnet array.

Abstract: The present invention provides a novel adsorbent composition for recovering biomolecules from a fluid. The composition comprises positively and negatively charged microparticles in the form of ground particles. The adsorbent is particularly useful for purification of biomolecules from the cell culture.

Abstract: The detection range and the detection precision of a sensor device that makes use of the deformation of a viscoelastic elastomer are made variable. The sensor device comprises a magnetic viscoelastic elastomer containing electroconductive magnetic particles dispersed therein so as to demonstrate an elastic modulus that varies depending on a magnetic field applied thereto and an electric resistance in a prescribed direction that varies depending on a deformation thereof, electromagnets for applying a magnetic field that can be varied to the magnetic viscoelastic elastomer, a resistance detection circuit for detecting the electric resistance of the magnetic viscoelastic elastomer, and a control unit for computing at least one of a deformation state of the magnetic viscoelastic elastomer and a load applied to the magnetic viscoelastic elastomer according to a detection value of the resistance detection circuit and a magnitude of the magnetic field applied by the electromagnets.

Abstract: An aspect of the present invention relates to a method of manufacturing hexagonal strontium ferrite magnetic powder, which comprises melting a starting material mixture which has a composition, as a composition converted into an oxide, lying within a region enclosed by the following four points: (a) SrO=48.0 mol %, Fe2O3=17.2 mol %, B2O3=34.8 mol %; (b) SrO=55.9 mol %, Fe2O3=17.7 mol %, B2O3=26.4 mol %; (c) SrO=41.7 mol %, Fe2O3=40.9 mol %, B2O3=17.4 mol %; (d) SrO=36.7 mol %, Fe2O3=40.1 mol %, B2O3=23.2 mol %; in a ternary diagram with SrO, Fe2O3, which may include an Fe substitution element, and B2O3 as apexes, to provide a melt, and quenching the melt to obtain a solidified product; and heat treating the solidified product to precipitate hexagonal strontium ferrite magnetic particles within the solidified product.

Abstract: The present disclosure relates to a sealing element for hollow sections, including a seal carrier that extends along a longitudinal axis and has two arms each of which has an outer face and an inner face and which are connected together, as one piece, at longitudinal edges that face each other such that they form a corner angle between them seals mounted on or near a free longitudinal edge of each arm and running parallel to the free longitudinal edge, on the outer face of the associated arm, and a securing device, on at least one inner face of an arm, for detachably securing the sealing element onto a corner of a hollow section. A cover cap serves to complete the sealing elements, the cap being provided, on its outer face, with one or more sealing sections designed to connect to ends of the seals of the sealing element.

Abstract: A system relating to providing printable/writable magnetic sheets comprising a favorable balance of mechanical rigidity and flexibility for improved handling during processing steps required for the manufacture of such printable/writable magnetic sheets.

Abstract: Disclosed is a hybrid filler for an electromagnetic shielding composite material and a method of manufacturing the hybrid filler, by which electromagnetic shielding and absorbing capabilities are improved and heat generated by electromagnetic absorption is effectively removed. The hybrid filler for an electromagnetic shielding composite material includes an expandable graphite (EG) having a plurality of pores, and magnetic particles integrated with a carbon nanotube (CNT) on outer surfaces thereof in a mixed manner, wherein the magnetic particles are inserted into the pores of the EG.

Abstract: A magnetic material composition includes: magnetic alloy particles such as Fe—Si—Cr or Fe—Si—Al based particles, with a passivation film formed on the surfaces of the particles; and a glass constituent that contains Si, B, and an alkali metal such as K, Na, and Li, and has a softening point of 650 to 800° C. The content of the glass constituent is 12 to 32 wt % with respect to the total of the magnetic alloy particles and the glass constituent. A glass phase formed from the glass constituent is formed between the magnetic alloy particles. A component body with a coil conductor buried therein is formed from the magnetic material composition. Thus, ingress of moisture and plating solutions between the magnetic alloy particles can be suppressed so that favorable insulation performance can be ensured without impairing any magnetic property.

Abstract: An actively controlled colloidal damper having controllable damping characteristics. The damper has a cylinder (2); a piston (4) reciprocatably guided and supported by the cylinder (2) and forming a closed space (3) in cooperation with the cylinder (2); a porous body (8) having a large number of fine holes and received in the closed space (3); operation liquid (7) received in the closed space (3) together with the porous body (8), flowing into the fine holes in the porous body (8) when the pressure in the closed space (3) is increased, and flowing out of the fine holes when the pressure in the closed space (3) is decreased, and pressure regulation means, such as a servo value (6) and a pump device (10), for regulating the pressure in the closed space (3).

Abstract: A method apparatus and material are described for radio frequency passives and antennas. In one example, an electronic component has a synthesized magnetic nanocomposite material with aligned magnetic domains, a conductor embedded within the nanocomposite material, and contact pads extending through the nanocomposite material to connect to the conductor.

Abstract: A hexagonal crystal ferrite magnetic powder having high magnetic characteristics while having a small particle volume and a high specific surface area is provided, and a high-density magnetic recording medium using the powder. A method for producing a hexagonal crystal ferrite formed using a glass crystallization method includes the steps of: mixing a glass matrix with raw materials including iron, bismuth, a divalent metal (M1), a tetravalent metal (M2), any one kind (A) of barium, strontium, calcium, and lead, and at least one kind of rare earth element (represented by R) having a mole equal to or less than that of the iron; heating the mixed raw material to obtain a glass body; quenching the glass body, pulverizing the glass body, and performing a heat treatment, and washing the glass body after the heat treatment with an acid solution.

Abstract: There is provided a double-layer composite metal powder particle including an Fe-based powder, an insulating layer formed on a surface of the Fe-based powder, and a lubricating wax coating layer formed on the insulating layer.

Abstract: There is provided a method of manufacturing a double-layer composite metal powder particle, the method including preparing an iron (Fe)-based powder particle, forming an insulating layer on a surface of the iron (Fe)-based powder particle, and forming a lubricating wax coating layer on the insulating layer.

Abstract: A black sealant composition includes magnetic nanoparticles including a core and a shell surrounding the core, conductive black particles having a black color, and a resin including the magnetic nanoparticles and the conductive black particles dispersed therein.

Abstract: Methods and materials are disclosed for use in recovering a biopolymer from a solution. In particular, the invention provides methods for extraction and isolation of nucleic acids from biological materials. The nucleic acids can be separated by forming a stable complex with soluble polysaccharide polymers and magnetic particles, in the presence of detergents and solvent. When the particles are magnetically separated out of the solution, the nucleic acids are separated with them. The nucleic acids can subsequently be released and separated from the particles. The nucleic acid preparation is useful for achieving efficient and accurate results in downstream molecular techniques such as quantification, identification of the source of the nucleic acids, and genotyping.

Abstract: Disclosed is a resin composition, which comprises a thermosetting resin contained therein in an amount of 40 volume % or more, and a wax contained therein in an amount of 5 to 30 volume %, wherein: the thermosetting resin exists in liquid form at room temperature; and the wax exists in powder form at room temperature and has a melting point of 70 to 150° C., and wherein the resin composition has a viscosity of 50000 to 150000 mPa·s as measured at room temperature.

Abstract: Disclosed is a hybrid filler for an electromagnetic shielding composite material and a method of manufacturing the hybrid filler, by which electromagnetic shielding and absorbing capabilities are improved and heat generated by electromagnetic absorption is effectively removed. The hybrid filler for an electromagnetic shielding composite material includes an expandable graphite (EG) having a plurality of pores, and magnetic particles integrated with a carbon nanotube (CNT) on outer surfaces thereof in a mixed manner, wherein the magnetic particles are inserted into the pores of the EG.

Abstract: A reactor 1 of the present invention includes a coil 2 and a magnetic core 3 disposed inside and outside the coil 2 to form a closed magnetic path. At least part of the magnetic core 3 is made of a composite material containing a magnetic substance powder made of an identical material and a resin containing the powder being dispersed therein. In the particle size distribution of the magnetic substance powder, a plurality of peaks are present. That is, the magnetic substance powder contains both a fine powder and a coarse powder at high frequencies. Since the composite material contains the fine powder, it can reduce the eddy current loss, and hence achieves to be a low-loss material. Thanks to the mixed powder including the fine powder and the coarse powder, the packing density of the magnetic substance powder is increased. Thus, the composite material exhibits a high saturation magnetic flux density.

Abstract: Provided are a soft magnetic powder for obtaining a dust core having a low iron loss, the dust core, and a method for producing a dust core. The present invention relates to a soft magnetic powder including a plurality of soft magnetic particles, each having an insulating layer. The Vickers hardness HV0.1 of a material constituting the soft magnetic particles is 300 or more, and the insulating layer contains Si, O, and at least one of an alkali metal and Mg. As long as the soft magnetic powder has such features, a material having a high electric resistance, such as an iron-based alloy, can be used. The eddy current loss can be reduced, and it is possible to effectively obtain a dust core having a low iron loss.

Abstract: A Ni—Zn—Cu ferrite material having excellent DC bias characteristics is provided by adding zinc silicate thereto. The above problem can be solved by Ni—Zn—Cu ferrite particles which comprise a spinel-type ferrite and zinc silicate, which have a composition comprising 36.0 to 48.5 mol % of Fe2O3, 7.0 to 38 mol % of NiO, 4.5 to 40 mol % of ZnO, 5.0 to 17 mol % of CuO and 1.0 to 8.0 mol % of SiO2, all amounts being calculated in terms of the respective oxides, and which have a ratio of an X-ray diffraction intensity from a 113 plane of the zinc silicate to an X-ray diffraction intensity from a 311 plane of the spinel-type ferrite is 0.01 to 0.12; a green sheet obtained by forming a material comprising the Ni—Zn—Cu ferrite particles into a film; and a Ni—Zn—Cu ferrite sintered ceramics.

Abstract: A composition for electromagnetic wave suppression and heat radiation includes: a matrix composed of a high molecular material or a low molecular material; and a magnetic particle filled in the matrix upon mixing a magnetic powder having a relation of {(tap density)/density}?0.58 with the matrix.

Abstract: Disclosed is a magnetic material having high Hc and High Curie point, which is capable of controlling such magnetic characteristics without requiring rare or expensive raw materials. Specifically disclosed is a magnetic material composed of particles of a magnetic iron oxide which is represented by the following general formula: ?-AxByFe2?x?yO3 or ?-AxByCzFe2?x?y?zO3 (wherein A, B and C each represents a metal excluding Fe and different from each other, satisfying 0<x, y, z<1), with ?-Fe2O3 as a main phase.

Abstract: Amine functionalized magnetic nanoparticle compositions and processes for synthesizing the same are described. The process consists of obtaining a carboxylated polymer in substantially pure form, which is used to prepare a substantially size homogeneous, polymer coated carboxyl, functionalized magnetic nanoparticle. The carboxyl groups are converted to reactive primary amino groups by the use of a water-soluble carbodiimide followed by reaction of a large excess of a diamine. The amine-terminated nanoparticles are then reacted with bifunctional crosslinking agents and with various biomolecules to make nanoparticles for in vitro assays, cell sorting applications and target specific MR contrast agents.

Abstract: To provide a high-frequency magnetic material having a superior radio wave absorption property in a high frequency region and a method of manufacturing the same. The high-frequency magnetic material and the method of manufacturing the same includes a magnetic substance containing metal nanoparticles, the metal nanoparticles are magnetic metals containing at least one kind of Fe, Co, and Ni, an average particle diameter of the metal nanoparticles is equal to or less than 200 nm, first clusters having network-like structures with continuous metal nanoparticles and the average diameter equal to or less than 10 ?m are formed, second clusters having network-like structures with the continuous first clusters and the average diameter equal to or less than 100 ?m are formed, and the entire magnetic substance has a network-like structure with the continuous second clusters.

Abstract: The present invention provides a powder for a magnetic member being excellent in moldability and difficult to oxidize, a powder compact produced from the powder, and a magnetic member suitable for a raw material of a magnetic member such as a rare earth magnet. A powder for a magnetic member includes magnetic particles 1 which constitute the powder for a magnetic member and each of which is composed of less than 40% by volume of a hydrogen compound 3 of a rare earth element, and the balance composed of an iron-containing material 2 which contains iron and an iron-boron alloy containing iron and boron. The hydrogen compound 3 of a rare earth element is dispersed in a phase of the iron-containing material 2. An antioxidant layer 4 having a low-oxygen permeability coefficient is provided on the surface of each of the magnetic particles 1.

Abstract: The present invention provides a magnetic sheet with improved resistance to folding while maintaining good magnetic characteristics and reliability; a method for producing the magnetic sheet; an antenna; and a portable communication device. A magnetic sheet of the present invention includes a flat magnetic powder, and a resin binder capable of dissolving in a solvent, wherein the magnetic sheet has a gradient of the content ratio of the magnetic powder to the resin binder in a thickness direction thereof, wherein, in use, the magnetic sheet is folded so that, of the front and back surfaces thereof, one surface whose magnetic powder content is lower than that of the other is folded inward, and wherein the difference in glossiness measured at a light-incident angle of 60° between the front and back surfaces is 9.4 or more.

Abstract: Disclosed is a magnetic material for high-frequency use in which lower loss is achieved. The magnetic material for high-frequency use is formed from a composite material of magnetic particles and resin, the magnetic particles consist of a simple metal, an alloy, or an inter-metallic compound and have a positive magnetostriction constant, and the shapes of the particles are flattened by means of mechanical processing.

Abstract: The invention relates to a cellular elastomer which is anisotropic, with anisotropy being defined by the compressive modulus in one of three orthogonal directions being greater than that in the other two directions by a factor of at least 1.5. The invention also relates to a cellular elastomer containing magnetizable particles which have a chain-like alignment along one spatial direction. The invention also relates to a process for producing a cellular elastomer containing magnetiable particles and the use of such elastomers in articles of manufacture.

Abstract: Solvent-based ink compositions which can be used for ink jet printing in a variety of applications. In particular, the present embodiments are directed to magnetic inks having desirable ink properties. The ink of the present embodiments comprise magnetic nanoparticles that are coated with various materials to prevent the exposure of the nanoparticles to oxygen, and provides robust prints.

Abstract: A phase change magnetic ink including a phase change ink carrier; an optional colorant; an optional dispersant; an optional synergist; an optional antioxidant; and an inorganic oxide coated magnetic nanoparticle comprising a magnetic core and an inorganic oxide shell disposed thereover.

Abstract: An ink including stabilized magnetic single-crystal nanoparticles, wherein the value of the magnetic anisotropy of the magnetic nanoparticles is greater than or equal to 2×104 J/m3. The magnetic nanoparticle may be a ferromagnetic nanoparticle, such as FePt. The ink includes a magnetic material that minimizes the size of the particle, resulting in excellent magnetic pigment dispersion stability, particularly in non-aqueous inkjet inks. The smaller sized magnetic particles of the ink also maintains excellent magnetic properties, thereby reducing the amount of magnetic particle loading required in the ink.

Abstract: A fluid includes a liquid medium having iron particles mixed therein. An organic phosphonate based coating is established on the iron particles. The organic phosphonate based coating does not substantially include phosphonic acid groups at an outer surface thereof, and increases oxidation resistance of the iron particles. A method of making such a liquid medium is also disclosed herein.

Abstract: An in situ process for preparing a phase change magnetic ink including heating a phase change ink composition to a first temperature sufficient to provide a melt composition; wherein the phase change ink composition comprises a carrier, an optional colorant, and an optional dispersant; placing the melt composition under inert atmosphere; heating the melt composition to a second temperature sufficient to effect decomposition of a metal carbonyl; adding the metal carbonyl to the melt composition under inert atmosphere at this second temperature to form metal nanoparticles thus forming in situ a phase change magnetic ink including the metal nanoparticles; optionally, filtering the phase change magnetic ink while in a liquid state; and cooling the phase change magnetic ink to a solid state.

Abstract: A process for the production of magnetic nanoparticles on a continuous basis from aqueous salt solutions, utilizes very rapid mixing of the reaction components to achieve particles with a uniform size and shape as well as narrow size distribution. The process includes a methodology to determine the necessary experimental conditions to achieve a sufficiently rapid mix of the reaction components, based on real-time measurements of the magnetic susceptibility of the precipitate during the precipitation reaction.

Abstract: Techniques for dyeing material are disclosed, including providing a magnetorheological fluid containing a coloring agent onto a contacting surface, applying a magnetic field to the magnetorheological fluid to increase viscosity of the magnetorheological fluid, and contacting the material with the magnetorheological fluid on the contacting surface to dye the material with the coloring agent.

Abstract: Methods and compositions for removing a contaminant from its environment. The method includes forming a magnetic composition comprising the contaminant and an amphiphilic substance, and applying a magnetic field to the magnetic composition so as to separate the magnetic composition from the environment. One composition includes a micelle array confined in a magnetic mesoporous framework. Another composition is formed by adhering an amphiphilic material comprising functional surface groups to a contaminant, then interacting a magnetic material with the functional surface groups of the amphiphilic material. In various versions, the contaminant can be a hydrophobic organic compound, or a fullerene-related nanoparticle. The methods can also be used to purify hydrophobic organic compounds or fullerene-related nanoparticles.

Abstract: A method for the production of pressed permanent magnets comprises the following steps: A mixture of at least one magnetic powder and a thermosetting binder is provided and pressed to produce a moulded body. In order to obtain a permanent and particularly reliable protection against oxidation and corrosion, the moulded body is impregnated with an acid and solvent mixture in an impregnating bath before the cure of the thermosetting binder, whereby the entire surface of the permanent magnet is coated with a reaction layer [FIG. 1].

Abstract: It is intended to provide a method capable of simply aggregating magnetic particles having a surface modified with a thermoresponsive polymer at a given temperature without heating or cooling an aqueous solution containing the magnetic particles, and a separation method and a detection method of a substance to be detected in a sample using the method. The method of separating a substance to be detected from a sample includes the steps of: mixing an adsorbent and the sample in an aqueous solution to adsorb the substance to be detected on the adsorbent, aggregating the adsorbent by changing a salt concentration in the aqueous solution; and collecting the adsorbent from the aqueous solution by a magnetic force, wherein said adsorbent comprises a magnetic particle of an average particle size of 50 to 1000 nm, a surface of which is modified with a thermoresponsive polymer and is immobilized with a substance having an affinity for the substance to be detected.

Abstract: Provided is a magnetic graphite nanoplatelet, and a method of manufacturing nanocomposites by introducing the magnetic nanoplatelets into a composite matrix. Expanded crystalline graphite, in the form of graphite nanoplatelets, is mixed with magnetic particles to adhere the particles to the nanoplatelets. The magnetic graphite nanoplatelets are combined with a composite matrix, typically a polymer, to form a nanocomposite. In the presence of an applied magnetic field, the magnetic graphite nanoplatelets orient and align consistent with the magnetic field to yield a composite having enhance mechanical, electrical and thermal properties.

Abstract: A composite materil comprises magnetic particles dispersed in electrically insulating material. The magnetic particles have an aspect ratio greater than 1 (preferably greater than 10) and a concentration sufficiently high to produce negative permeability. The magnetic particles may be magnetic flakes of reduced carbonyl iron of average diameter 50 ?m, average thickness 1 ?m and aspect ratio 50, the magnetic flakes being at least 25% by volume of the composite material. The magnetic flakes may be aligned to produce enhanced permeability. The electrically insulating material may be paraffin wax, particulate PTFE, or another polymer. To control permittivity, the composite material may include an electrically conducting component such as graphite or conductive coatings upon the magnetic flakes.

Abstract: A magnetic paint is prepared by a method comprising a surface-treating step for magnetic powder, to obtain a first composition by mixing and stirring a composition which comprises a magnetic powder, a dispersant and/or a binder resin, and an organic solvent, and which contains 40% by weight or less of a non-solvent component, while applying a shear force to the composition; and a concentrating step to obtain a second composition by concentrating the first composition until the content of the non-solvent components of the first composition reaches 80% by weight or more.

Abstract: An electromagnetism suppressing material has an increased electromagnetism suppressing effect, can be flexibly formed in various shapes, and is inexpensive. An electromagnetism suppressing device uses the electromagnetism suppressing material, and an electronic appliance uses the electromagnetism suppressing material or the electromagnetism suppressing device. The electromagnetism suppressing material is a liquid material and/or gel material with electrical polarity.

Abstract: The present invention relates to compositions such as coatings, printing inks or cosmetics, which contain pigments comprising or consisting of a layer made of a material with an index of refraction that is higher than the index of refraction of the adjacent material by at least 0.25; whereas said layer has a zero-order diffractive micro-structure; whereas said layer acts as an optical waveguide and whereas said layer has a thickness between 50 nm and 500 nm; to processes for its manufacture and to its use. These pigments show a colour effect upon rotation and/or tilting, and it is believed that this colour effect is based on zero-order diffraction.