摘要:
A process and apparatus prepares and collects metal nanoparticles by forming a vapor of aluminum or copper metal that is solid at room temperature, the vapor of the metal being provided in an inert gaseous carrying medium. At least some of the metal is solidified within the gaseous stream. The gaseous stream and metal material is moved in a gaseous carrying environment into or through a dry mechanical pumping system. While the particles are within the dry mechanical pumping system or after the nanoparticles have moved through the dry pumping system, the vaporized metal material and nanoparticles are contacted with an inert liquid collecting medium.
摘要:
The present invention describes a novel method for the formation of optically variant pigments by the coating of layers onto a substrate and the fracturing of the coated material into pigment particles after the coating operation and novel pigments produced thereby. Coating techniques such as slot die coating (especially multiple slot die coating), spin coating, meniscus coating, curtain coating, and the like have proven successful. It is preferred that multiple die slots are used to coat multiple layers in a single pass so that manufacturing costs are minimized. The use of these coating techniques, and especially multiple die slot coating, allows for many layers to be coated, with from three to fifty layers being readily possible. This offers a relatively inexpensive way of coating out a wide variety of layers, and especially the pigment materials needed for optically variable pigments, quickly and with high quality. The coating materials may be sols, polymers, composites, reactive mixtures and the like, including combinations of these materials. The properties of the optically variable pigment are determined by the composition, properties and thickness of the coated layers.
摘要:
The present invention provides a process for adhering a liquid to a particulate substrate. The process comprises the steps of:a) providing an apparatus which can create an oscillating magnetic field within a chamber,b) providing particulate magnetic material within the chamber of said apparatus while said oscillating field is active,c) having in the chamber within the oscillating magnetic field a liquid coating material and a particulate substrate to be coated with said liquid,d) and having said magnetic field form a fluidized bed of at least said particulate magnetic material, said liquid coating material coating the surface of the particulate substrate, ande) optionally continuously collecting the coated particulate substrate.The particulate magnetic material may be added to the chamber before or after the magnetic field has been activated to oscillate. The field may be active when the magnetic particles are added, and the field may be activated only after the magnetic particles are present as a non-fluidized sedentary bed. The liquid may likewise be added at any time. The liquid coating material may be added before the field is activated, or after the field is activated. The liquid may be added before the magnetic particles are added, at the same time or after the magnetic particles are added. The magnetic particles may provide the only particulate surface onto which the liquid is to be coated, or separate particulates may be used along with the magnetic particulate materials. The magnetic particulates may be included along with the non-magnetic particulates in the final desired product, or the coated magnetic particles may be easily separated from the non-magnetic particles by magnetic filtering or screening. This process provides a significant benefit in a liquid coating process by reducing the potential for waste and allowing easy recycling of coating material.
摘要:
Precisely shaped composites and methods for making these composites are disclosed. The method of this invention comprises the steps of: (a) providing a production tool having a plurality of cavities; (b) providing a dispensing means capable of introducing a binder precursor comprising a thermosetting resin into the cavities; (c) providing a means, within a curing zone, for at least partially curing the binder precursor; (d) introducing the binder precursor into at least a portion of at least two of the cavities; (e) continuously moving the production tool through the curing zone to at least partially cure the binder precursor to provide a solidified, handleable binder; (f) removing the binder from said at least one cavity; and (g) converting the binder into precisely shaped composites. Steps (f) and (g) can be conducted simultaneously. The composites are bonded to a backing to form a coated abrasive article.
摘要:
An energy polymerizable composition and process therefore, comprising a cationically polymerizable material and a catalytically effective amount of an ionic salt of an organometallic complex cation as polymerization initiator, said ionic salt of an organometallic complex cation being capable of adding an intermediate strengeth nucleophile or upon photolysis capable of liberating at least one coordination site, said metal in said organometallic complex cation being selected from elements of Periodic Groups IVB, VB, VIB, VIIB, and VIIIB are disclosed. Certain of the organometallic metallic polymerization initiators are novel cationic salts.
摘要:
A dispersion and a method therefor wherein the dispersion has composition A or B, whereinA is a nonaqueous dispersion comprising pigment particles having an average size of less than 0.1 micrometer dispersed in an organic medium, andB is an aqueous dispersion comprising certain classes of inorganic pigment particles having an average size of less than 0.1 micrometer dispersed in an aqueous medium, wherein said classes of inorganic pigment particles are selected from the group consisting of metal oxides and metal salts.The method of the invention comprises the steps of vaporizing a pigment or pigment precursor in the presence of a nonreactive gas stream to provide ultrafine pigment or pigment percursor particles, when pigment precursor particles are present, providing a second gas capable of reacting with said ultrafine pigment precursor particles and reacting said second gas with said ultrafine pigment precursor particles to provide ultrafine pigment particles, transporting said ultrafine pigment particles in said gas stream to a dispersing medium, to provide a dispersion of pigment particles in said medium.
摘要:
A dispersion and a method therefor wherein the dispersion has composition A or B, whereinA is a nonaqueous dispersion comprising pigment particles having an average size of less than 0.1 micrometer dispersed in an organic medium, andB is an aqueous dispersion comprising certain classes of inorganic pigment particles having an average size of less than 0.1 micrometer dispersed in an aqueous medium, wherein said classes of inorganic pigment particles are selected from the group consisting of metal oxides and metal salts.The method of the invention comprises the steps of vaporizing a pigment or pigment precursor in the presence of a nonreactive gas stream to provide ultrafine pigment or pigment precursor particles, when pigment precursor particles are present, providing a second gas capable of reacting with said ultrafine pigment precursor particles and reacting said second gas with said ultrafine pigment precursor particles to provide ultrafine pigment particles, transporting said ultrafine pigment particles in said gas stream to a dispersing medium, to provide a dispersion of pigment particles in said medium.
摘要:
A reduced friction composite sheet construction comprises a semicrystalline polymeric sheet support having a first and second surface, said surfaces having in the range of 5 to 99 percent crystalline polymeric material and 1 to 95 percent amorphous polymeric material, said first surface having been subjected to sputter-etching which preferentially ablates said amorphous material compared to said crystalline material so as to provide on said first surface ridges or needles of amplitude in the range of 0.01 to 5.0 micrometers, and a separation at their apexes in the range of 0.01 to 1.0 micrometers and having an aspect ratio in the range of 0.5 to 7, said first surface having at least one of static and dynamic coefficients of friction in the range of 0.01 to 0.7, and at least one functional layer coated on said second surface of said support.