Showing papers on "Coating published in 1983"

On the mechanical behavior of brittle coatings and layers

Abstract: This paper examines several important issues concerning the mechanical properties of coatings, films, and layers. Major emphasis has been placed on descriptions of residual stresses and their influence on mechanical failure of the coating. The residual stresses are shown to depend on the details of the coating or oxidation process, the general curvature of the substrate, the waviness of the coating-substrate interface, and the stress relaxation characteristics of the coating. Residual stress-induced coating failures, which consist either of coating fractures or spalling, are described. The latter is usually more serious and has been afforded primary attention. It is shown that spalling of the coating is a consequence of buckling, when the coating is subject to significant residual compression. The conditions needed to induce buckling and subsequent spalling are described.

Low surface energy liner of perfluoropolyether

Abstract: Low surface energy liner provided by segments of a perfluoropolyether monomer which has been in- situ-polymerized into a cohesive network which is adhered to a substrate. The low surface energy liner is especially useful as a low-adhesion backsize coating for a pressure-sensitive adhesive tape.

High-solids coating composition for improved rheology control containing chemically modified inorganic microparticles

Abstract: Disclosed is an essentially solvent-based, organic, high-solids coating composition containing (A) a film-forming binder system containing a crosslinkable resin having a weight average molecular weight of from about 500 to about 10,000; (B) substantially colorless, substantially inorganic microparticles stably dispersed in the coating composition; and (C) a solvent system for the crosslinkable resin. The inorganic microparticles prior to incorporation in the coating composition range in size from about 1 to about 150 nanometers and are in the form of a sol of the microparticles in which carbon-containing molecules are chemically bonded to the inorganic microparticles at the surface of the microparticles.

Low emissivity coatings on transparent substrates

Abstract: A low emissivity coating on a transparent substrate of glass or plastics material is produced by cathode sputtering a layer of silver and thereafter reactively sputtering an anti-reflection metal oxide layer over the silver in the presence of oxygen or an oxidizing gas, wherein a small amount of an additional metal other than silver is sputtered onto the silver before the overlying anti-reflection metal oxide layer is applied. The process produces a new low emissivity coated product comprising a glass or plastics substrate with a low emissivity coating comprising a silver layer, a small amount of additional metal dispersed non-uniformly in the silver layer and possibly extending over the silver layer, and an overlying anti-reflection metal oxide coating.

Proppant for well fractures and method of making same

Abstract: The novel proppant consists of composite particles, the core of which is a conventional proppant particle such as silica sand The core has a thin, void-containing coating which provides an overall density approaching that of the fracturing fluid The coating preferably comprises hollow glass microspheres embedded in an adhesive which bonds the microspheres to the core

Method of consolidating a metallic body

Abstract: A method of consolidating a metallic body is disclosed. The method comprises the steps of forming an article of manufacture from powdered metal; sintering the article of manufacture so as to increase the strength thereof; coating the article with a sacrificial layer of ceramic; providing a bed of heated, generally spheroidal ceramic particles; compacting the coated article of manufacture embedded in the heated bed under pressure to thereby consolidate the article into a dense, desired shape; and, removing said sacrificial coating such that the surface of the article remains substantially free of process-related imperfections.

Process of coating a substrate with an abrasion resistant ultraviolet curable composition

Abstract: A process of coating a solid substrate with an abrasion resistant silicone hard coating composition which is curable upon exposure to ultraviolet radiation under a non-inert atmosphere, such as air, is provided. The coating composition is comprised of a combination of UV light crosslinkable polyfunctional acrylate monomers, SiO 2 in the form of colloidal silica, and acryloxy functional silanes and a selected blend of ketone-type and hindered amine-type photoinitiators.

Structure and oxygen-barrier properties of metallized polymer film

Abstract: The structure of thin (10 to 50 nm) aluminium layers vacuum deposited on to polyester film is examined using both transmission electron microscopy and light microscopy. The density of pinhole defects in the aluminium coating, quantified by an image analysing microscope, is shown to determine the permeability of the film to oxygen. Finite element calculations of the effect of various pinhole diameters and densities on the permeability agree with experiment, and also show that the barrier properties of the polymer layers immediately adjacent to the metal coating are critical in determining the deleterious effect of pinhole defects.

The influence of particle size and surface coating of calcium carbonate on the rheological properties of its suspensions in molten polystyrene

Abstract: The rheological properties of polystyrene melts filled with 30 vol % of CaCO3 particles of varying particle size are described. The influence of surface coating the particles with stearic acid is considered. Generally, the compounds with the uncoated particles exhibit viscosities which increase at ever greater rates as the shear rates decrease. It appears that these compounds exhibit yield values. Elongational flow data also suggest the existence of yield values. Difficulties exist in measurement of normal stresses in compounds with sizeable yield values. The principal normal stress difference at fixed shear stress of the PS/CaCO3 compounds is lower than that of the PS melt. The magnitude of viscosity increases and yield values increase with decreasing particle size. Coating of particles with stearic acid results in major viscosity reductions and decreases in apparent yield values. The surface coating is most effective with the smallest particles. It presumably reduces interaction between particles and the extent of aggregation.

Coated ophthalmic lenses and method for coating the same

Abstract: An ophthalmic lens and a method for providing a thin coating thereon is disclosed. The coatings render the surfaces of the devices resistant to abrasion and have an SEB abrasion resistance of at least 20 psi. They are optically clear, aberration-free, and provide essentially exactly an optical surface having the desired surface configuration. The coating compositions employed contain reactive ethylenically unsaturated groups and are applied to a mold face and partially reacted. The coated mold is then used to cast the ophthalmic device.

Method of preparing curable coating composition from alcohol, colloidal silica, silylacrylate and multiacrylate monomer

Abstract: UV curable coating compositions are provided based on the use of photoinitiator with the hydrolysis product of silylacrylate and aqueous colloidal silica. The UV curable silicone coating compositions also can contain polyfunctional acrylate. The UV curable hardcoat composition can be applied onto various substrates, for example, a polycarbonate substrate, and thereafter cured under UV radiation to produce adherent and abrasion resistant coated articles.

Method of making a rotary ball display device

Abstract: A method for manufacturing rotary ball display devices wherein a plurality of such balls are provided with a coating of a color different from the remainder of the ball, the ball members are coated with a thin coating insoluble in the settling medium into which they are introduced, so that upon settling into a low viscosity liquid, they form a uniform layer. A high molecular weight hardenable coating material which is soluble in the low viscosity liquid is then poured onto the coated ball members to cover the layer. Then, the low viscosity liquid is removed and the hardenable coating material is caused to harden. The thin coating is then dissolved away from portions of the ball members to leave cavity portions thereabout into which a high resistivity liquid is introduced. The resulting ball members have a refractive index on the colored layer which is substantially the same as the refractive index of the high resistivity liquid contained in the cavities.

Seed coating machine

Abstract: A seed coating machine comprising an upper mixing drum wherein a liquid adhesive coating is applied to seed and where the rate of application is regulated by a valve controlled by the seed feeder. Coated seed is dried to a state of tackiness and passed to a second, lower mixing drum. A variety of powders are applied onto the tacky seed after being mixed and sifted in a screen distributor. The resulting coated seed has an outer powder layer which adheres to the inner adhesive coating.

Method for providing a coating layer of silicon carbide on the surface of a substrate

Abstract: The invention provides a novel method for providing the surface of various kinds of substrate articles, e.g. sapphire, quartz, alumina, metals, glass, plastics and the like with a coating layer of an amorphous silicon carbide of the formula Si x C 1-x , in which x is a positive number of 0.2 to 0.9, by exposing the surface of the substrate article to an atmosphere of plasma generated in a gaseous atmosphere of an organosilicon compound having no halogen or oxygen atom directly bonded to the silicon atom, such as hexamethyl disilane, optionally admixed with a vapor or gas of a hydrocarbon compound, e.g. methane, benzene and the like.

Vinyloxy-functional organopolysiloxanes compositions

Abstract: Photo-curable vinyloxy-functional organosiloxane polymers. Also provided are release coating compositions made by combining said polymers with various photo-initiators. The polymers have a unique vinyloxy functionality; and the release coating composition cure with brief exposure to ultraviolet radiation to form premium adhesive coatings. Process for preparing the vinyloxy-functional polysiloxanes and the release coating are also disclosed.

Overlays coating for superalloys

Abstract: Improved coating compositions are described for the protection of superalloys at elevated temperatures. The coatings are of the MCrAlY type where M is nickel or cobalt and are significantly improved by the addition of from 0.1-7% silicon and 0.1-2% hafnium. Coatings of the invention are preferably applied by plasma spraying and as so applied are found to be substantially more effective than prior art coatings.

Investigation of the solvent‐evaporation effect on spin coating of thin films

Abstract: A simple empirical relationship exists between the thickness and the solvent-evaporation rate of spin-coated thin films. The thickness of a film formed from an organic solvent solution can be approximated by the relationship, where μ is the viscosity of the coating solution, ω is the rotation speed, E is the solvent-evaporation rate, λ is the latent heat of evaporation, Cp is the heat capacity of the solvent, and K0 is a constant for volatile organic solvents. A similar relationship for aqueous polymer solutions is, where RH is the relative humidity of air around the spin coater and Ka is a constant for aqueous solutions. These relationships are helpful in understanding the mechanism of thin-film formation in spin coating.

Whitney Award Lecture—1983: Towards a Better Understanding of Corrosion beneath Organic Coatings

Abstract: A review is given of research whose objective is to understand the principles governing corrosion beneath organic coatings. Eight subject areas of special interest are discussed: electrical properties of coatings, the nature of the metal substrate in determining coating performance, electrochemical processes which take place on the metal substrate under the coating, diffusion of reactants through the coating, studies of the metal/coating interface, aggregation of water at the metal/coating interface, inhibitors in coatings, and a specific type of deterioration known as cathodic delamination.

Process for the preparation of a hydrophilic coating

Abstract: A process for coating a polymer surface with a hydrophilic coating with low friction in wet condition. The process comprises applying to the polymer surface a solution containing between 0.05 to 40% of a compound which comprises at least two unreacted isocyanate groups per molecule, evaporating the solvent, applying a solution containing between 0.05 to 50% of polyethylene oxide to the thus treated polymer surface and then evaporating the solvent of the last mentioned solution, and curing the coating at elevated temperature. The process is preferably carried out in the presence of a catalyst for the curing of isocyanate.

Sequential heteropolymer dispersion and a particulate material obtainable therefrom, useful in coating compositions as an opacifying agent

Abstract: The present invention is concerned with the production and use of water-insoluble particulate heteropolymers made by sequential emulsion polymerization in dispersed particles of which a "core" of a polymeric base is at least partially encased in a "sheath" polymer that is permeable to an acid, such as acetic acid, adapted to cause swelling of the core by neutralization. The aqueous dispersion of the acid-swollen, base-containing core/sheath particles is useful in making water-base coating compositions, microvoids being formed in cores of the swollen particles in the film during the drying thereof. Thus, the heteropolymer dispersion can serve as an opacifying agent in coating compositions, such as water-base paints, as a supplement or replacement of part or all of the pigmentary material or extenders that would otherwise be used in such coating compositions. For convenience of description herein, the terms "core", "sheath", and "core/sheath polymer" are frequently used to refer to the distinct functional components of the individual polymer particles of the essential "mode" of the heteropolymers of the present invention even though in actuality, the components of the polymer particles thereof may not have the precise arrangement implied by this terminology.

Selective removal of coating material on a coated substrate

Abstract: In accordance with the invention, an improvement in the process for the production of a plurality of semiconductor devices from a single substrate comprises contacting at least one surface of the substrate adjacent the peripheral edge thereof with means capable of rendering the coating material into a selectively more easily removable form than the remainder of the coating material. Selective peripheral portions of the coating material are then removed which mitigates the inadvertant dislodgement of coating particles from the peripheral portion of the substrate during subsequent processing of the coated substrate. In a preferred embodiment, the coating material is removed by contacting the peripheral portions of the coated substrate with a chemical which is a solvent for the coating.

Stretchable microfragrance delivery article

Abstract: An article comprises sheet material which may be printed and having an adherent coating of microscopic, rupturable capsules in a binder on at least one surface thereof, the article being capable of undergoing plastic deformation and exhibiting: (a) a yield point on a stress-strain curve of less than 225 kg/cm 2 (3200 psi) for a 127 micrometer (5 mil) thick material, (b) a difference in elongation at the yield point compared to the breaking point of at least 5.0 percent, and (c) an elongation at the yield point of less than 25 percent.

Plastic container with decreased gas permeability

Abstract: A container made of an organic resin having improved vapor barrier characteristics is disclosed which achieves an improved barrier by the placement thereon of a thin coating of an inorganic material.

Method for preparing a pharmaceutical controlled release composition

Abstract: A pharmaceutical oral multiple-units composition with controlled release, in which the individual units are coated units of an active substance, e.g. potassium chloride, which is subject to controlled release in consequence of the units being coated with a substantially water-insoluble, but with a water-diffusable coating, is prepared by applying on units comprising the active substance, a film-forming coating mixture comprising a solvent, a film-forming substance dissolved in the solvent and a hydrophobic substance, such as a wax, e.g. a paraffin wax, the film coating mixture being applied at a temperature higher than the melting point of the hydrophobic substance. The application is preferably performed in a fluidized bed. By thus incorporating a hydrophobic substance in the coating mixture in an amount of the order 1-25% in such a way that prior to the application, the hydrophobic substance is melted, but undissolved and microdispersed in the coating mixture, a coating is obtained which delays and controls the diffusion through the coating so that even easily soluble active substances, such as potassium chloride, can be slowly released.

Photochromic coating composition and photochromic synthetic resin ophthalmic lens

Abstract: Photochromic coating compositions for synthetic resin ophthalmic lenses to impart photochromic properties to the lenses are provided. The photochromic coating composition includes an organic silicon compound to impart a surface hard coating and a photochromic material dispersed in the hard coat to impart photochromic properties. The photochromic materials may include compounds including the molybdic acid amine group, dithizone-mercury polymers, halogenated silver or copper, and a benzopyrylospiran compound. The coating composition is prepared by dispersing the photochromic material in a silicon hard coating composition. The coating composition may be coated on the surface of a synthetic resin lens by dipping, spraying, spin coating, flow coating and the like and then dry-heated to be cured. The coating composition is applied in thicknesses from about 1 to 30 microns. The synthetic resin lenses which may be coated are transparent resins, such as polycarbonate resins, acryl resin, CR-39 resins, polystyrene and the like.

Magnetic recording medium

Abstract: PURPOSE:To make an in-plane magnetized film for improving reading efficiency usable for a vertically magnetized Ba-ferrite film and usable stably for a Co contg. alloy film as well by using a coating film contg. a pigment composed of soft magnetic particulate powder for said magnetized film. CONSTITUTION:The magnetic powder having high magnetic permeability used for a soft magnetic coating film 2 is constituted of a coating in which Mn-Zn ferrite is used as a pigment and an epoxy resin is used as a binder and of which the concn. by weight of the pigment is 2. The coating 2 is applied on a base material and is dried. The coating film is polished after calendering to heve 5mum final film thickness and 0.02mumRa surface roughness. A vertically magnetized film 3 is constituted by forming a film having 500Oe coercive force Hc1 in a vertical direction, 270emv saturation magnetization Ms and 1.0mum film thickness by sputtering method on the film 2 in the case of using a Co-Cr alloy film and forming a coating film having Hc1=900Oe, Ms=125emv and film thickness = 4mum on the film 2 in the case of using a Ba-ferrite coating film.

Paper machine belt

Abstract: An endless impervious, oil, abrasion and crush resisting belt for paper making machinery such as presses, especially of the extended nip type, calender rolls, and the like has a woven fiber base, such as scrim, and a urethane coating impregnating the base providing an integral layer of substantial thickness with pores forming a granite like finish providing excellent paper release properties. The surface finish of the belt can be modified with subsequent grinding and coating treatments and can be grooved if desired. The belt is formed by looping an endless scrim blanket around driving rollers providing a travelling run which is sprayed with a two component polyurethane coating which quickly gels to accommodate building up of a layer of the desired thickness by controlling the fluid flow and the speed of the travelling run.