Abstract: The present invention provides a powder composition in multiple separate parts comprising one or more than one resinous powder component in one or more than one part and, for each resin component, one or more than one powder, liquid or gaseous curing agent component in one or more than one separate part, wherein the average particle size ratio of each resinous powder component to its curing agent powder or droplet component ranges from 1.3:1 to 60:1 to insure the attraction of the resin and its curing agent to one another. Useful resins may include epoxy resin, polyester resin or their combination. The shelf life of the powder composition can be extended indefinitely by storing each resin and its curing agent in separate parts. However, each resin and its curing agent react within a period of from 0.01 to 600 seconds to form a cured powder coating when combined at a temperature of from 20° C. and 200° C. to enable very low temperature cure.

Abstract: Heat sensitive substrates, as well as others such as metal or glass, are electrostatically coated with a thermosetting coating powder comprising a melt-mixed, chilled, chipped, and powdered blend of an epoxy resin and a catalyst therefore, and a powdered low temperature curing agent along with conventional additives. The coating powder is deposited on the substrate and heated to fuse, flow and cure. The mixture of resin and catalyst does not cure within the extruder but it is made to cure at low temperatures on the desired substrate by the separate addition of the curing agent to the powdered melt-mixed blend. A small amount of the low temperature curing agent, insufficient to cause substantial curing in the molten stage may be used in place of the catalyst.

Abstract: A coating powder comprising a macrocyclic oligomer and a ring-opening polymerization agent is applied to an article, fused, and converted to a linear polymer at a temperature of from about 160 to about 400° C. The powder has the low melt viscosity and friability of a thermoset powder but is converted at high fusing temperatures to a tough coating having the good impact resistance and good elongation of a thermoplastic powder. The oligomer is a polyester, polycarbonate, polyamide, polyimide, polyamideimide. The article may be coated electrostatically or in a fluidized bed.

Abstract: A coating powder comprising a macrocyclic oligomer and a ring-opening polymerization agent is applied to an article, fused, and converted to a linear polymer at a temperature of from about 160 to about 400° C. The powder has the low melt viscosity and friability of a thermoset powder but is converted at high fusing temperatures to a tough coating having the good impact resistance and good elongation of a thermoplastic powder. The oligomer is a polyester, polycarbonate, polyamide, polyimide, polyamideimide. The article may be coated electrostatically or in a fluidized bed.

Abstract: A process of forming coatings on substrates by applying a layer of curable materials in dry powder form and then melting and curing the material is improved by compressing the layer using a flexible confining membrane. Less material is required to provide equivalent barrier protection and surface finish. The process is particularly applicable to applying dry powder coatings on temperature sensitive substrates, such as medium density fiberboard, in press apparatus, such as a membrane press, which have not commercially used dry powder coating materials previously.

Abstract: An atomized fluid, such as a mist of water, is applied to a preheated substrate, such as wood, a wood product, paper, or ceramic just prior to or contemporaneously with electrostatically applying a coating powder to the substrate. The atomized fluid is absorbed or adsorbed by the substrate so as to enhance the charge-carrying capacity of the substrate to an extent necessary to promote efficient electrostatic application of the coating powder to the substrate.

Abstract: Wood is electrostatically coated with a thermosetting powder coating system in which a mixture of a self-curing epoxy resin and a catalyst therefore is extruded and a low temperature curing agent are both pulverized and the powders are blended with conventional additives to make a coating powder which is deposited on a wooden substrate and heated to cure. The mixture of resin and catalyst does not cure within the extruder but it is made to cure at low temperatures by the separate addition of the curing agent. A small amount of the low temperature curing agent, insufficient to cause substantial curing during extrusion may be used in place of the catalyst.

Abstract: Wood is electrostatically coated with a thermosetting powder coating system in which a mixture of a self-curing epoxy resin and a catalyst therefore is extruded and a low temperature curing agent are both pulverized and the powders are blended with conventional additives to make a coating powder which is deposited on a wooden substrate and heated to cure. The mixture of resin and catalyst does not cure within the extruder but it is made to cure at low temperatures by the separate addition of the curing agent. A small amount of the low temperature curing agent, insufficient to cause substantial curing during extrusion may be used in place of the catalyst.

Abstract: A coating powder based on an epoxy resin is applied to a substrate and fused and cured thereon. Curing is effected by exposing the coating powder at the point of application to a fluid curative or cure catalyst, e.g., by exposing the fusing coating powder to an ammonia-containing atmosphere.

Abstract: Thermosetting powder coating compositions adapted to form a grainy textured finish on heat sensitive substrates, especially wood products, such as particle board, conductive particle board, and medium density fiber board, without damaging the substrates comprise an epoxy resin, particularly bisphenol A type epoxy resins having low viscosities, either a catalytic curing agent comprising an imidazole, a substituted imidazole, or adduct of an imidazole or substituted imidazole and an epoxy resin, or a curing agent comprising an adduct of a polyamine and an epoxy resin, or a combination of the catalytic curing agent and curing agent, a texturing agent, a flow control agent, optional extender, and optional pigment. The thermosetting powder coatings have a cure time/temperature ranging from about 30 seconds at about 350.degree. F. peak substrate temperature down to about 20 minutes at about 225.degree. F.

Abstract: Wood is electrostatically coated with a thermosetting powder coating system in which a mixture of a self-curing epoxy resin and a catalyst therefore is extruded and a low temperature curing agent are both pulverized and the powders are blended with conventional additives to make a coating powder which is deposited on a wooden substrate and heated to cure. The mixture of resin and catalyst does not cure within the extruder but it is made to cure at low temperatures by the separate addition of the curing agent. A small amount of the low temperature curing agent, insufficient to cause substantial curing during extrusion may be used in place of the catalyst.

Abstract: A coating powder consisting essentially of generally spherical particles ranging in size from less than 2 to about 40 microns, 75% of whose volume consists of particles of from about 2 to about 20 microns in size, is provided by dissolving the components of the coating powder in a supercritical fluid without the aid of a surfactant and spraying the solution into a zone whose pressure is less than that of the fluid. A very smooth continuous film of a cured thermosettable coating powder is achieved even when the film thickness is less than 1 mil, e.g., from about 0.2 and greater. The advantages of powder coatings may now be realized fully in the automobile and can industries.

Abstract: A thermosetting epoxy resin powder coating composition is provided that comprises an epoxy resin composed of a diglycidyl ether of bisphenol A, a curing agent composed of a bisphenol A encapped diglycidyl ether of bisphenol A, and a cure catalyst composed of an imidazole adducted to a diglycidyl ether of bisphenol A, in which the ratio of curing agent to epoxy resin is below 70% stoichiometry, and preferably between about 10% and 60% stoichiometry. The thermosetting epoxy resin powder coating composition not only exhibits the desired flexibility and fast cure speeds, but also exhibits superior adhesion and superior resistance to delamination and cathodic disbondment, preferably having cathodic disbondment values typically less than 4 mm radial disbondment, and preferably less than 2 mm radial disbondment. Such properties are highly advantageous for protective powder coatings used on rebars and pipelines.

Abstract: Unsaturated polyester resin coating powder composition consisting essentially of at least one unsaturated polyester resin; at least one copolymerizable second resin; and an initiator which comprises 1,1'-di(t-butylperoxy)-3,3,5-trimethylcylcohexane (AE), or which contains a small proportion of a fast initiator and a relatively large proportion of a slow initiator as defined herein. Initiator AE has been found to work better as a single initiator than other initiators previously employed in in-mold powder coating formulations. The combination of initiators works better than either one alone, and better than any of the few moderate rate initiators available.

Abstract: Unsaturated polyester resin coating powder composition consisting essentially of at least one unsaturated polyester resin; at least one copolymerizable second resin; and an initiator which comprises 1,1'-di(t-butylperoxy)-3,3,5-trimethylcyclohexane (AE), or which contains a small proportion of a fast initiator and a relatively large proportion of a slow initiator as defined herein. Initiator AE has been found to work better as a single initiator than other initiators previously employed in in-mold powder coating formulations. The combination of initiators works better than either one alone, and better than any of the few moderate rate initiators available.

Abstract: The hydrolysis of carbon oxysulfide in a gas or liquid stream is catalyzed by morpholines and piperazines at a temperature in the range from about 50.degree. about 90.degree. C. The process can be used in the treatment of refinery gases, coal gasification streams, and other such gases as well as liquid hydrocarbons which contain COS and other acidic contaminants.

Abstract: .[.Wood.]. .Iadd.A heat sensitive substrate .Iaddend.is .[.electrostatically.]. coated with a thermosetting powder coating system in which a mixture of a self-curing epoxy resin and a catalyst therefore is extruded and .Iadd.pulverized and .Iaddend.a low temperature curing agent .[.are both.]. .Iadd.a .Iaddend.pulverized and the powders are blended with conventional additives to make a coating powder which is deposited on .[.a wooden.]. .Iadd.the .Iaddend.substrate and heated to cure. The mixture of resin and catalyst does not cure within the extruder but it is made to cure at low temperatures by the separate addition of the curing agent. A small amount of the low temperature curing agent, insufficient to cause substantial curing during extrusion may be used in place of the catalyst.