Abstract: A method of decreasing the expansion temperature and improving the expansion characteristics of vermiculite ore comprising subjecting vermiculite ore containing interlamellar cations to a potassium nitrate solution for a time interval sufficient to ion-exchange interlamellar cations within said ore with potassium ions. Subsequent to this ion exchange the low temperature expandable vermiculite may be expanded by heating in an oven, or incorporated in an intumescent material and heat expanded in situ, or expanded by other heating means. An intumescent sheet is provided which may be used for mounting automotive catalytic converter monoliths comprising an unexpanded vermiculite produced by the method of the invention; an inorganic fibrous material; and a binder.
Abstract: Photosensitive resin compositions which can be used to prepare solder masks of improved stability are provided, together with a method of forming a cured, imagewise distribution of the solder mask composition on a printed circuit board substrate.
Abstract: Disclosed is a universal platen holddown apparatus that includes a first plate rotatable about its central axis, and a second plate that is rotatable about its own central axis. The first plate is mounted within the second plate so that rotation of the second plate results in the eccentric rotation of a vacuum suction cup 14 mounted at or near a rim of the first plate. This arrangement allows the suction cup to be moved to any location within the boundaries of the second plate.
Abstract: Masonry cement additives are provided which, when interground with Portland cement, produce a masonary cement having superior workability, plasticity and board life, while unexpectedly also having advantageously low levels of entrained air. The additives of the invention enable the masonry cement producer to obtain these desired properties without replacing the limestone component of the masonry cement with more costly lime.The additives of the invention may be provided in aqueous solution, and thus, unlike emulsion additives, are stable for long periods of storage, even when subjected to extreme temperature excursions and cycling.The additives of the invention comprise a salt of stearic acid; a set retarding carbohydrate; an ethylenic glycol elected from the group consisting of mono-, di-, tri-, and tetraethylene glycols; and a cellulose ether.
Abstract: Stable vermiculite dispersions which are substantially free of settling and a method of preparing same are provided. The dispersions are obtained by treating the vermiculite platelets of which the dispersion is comprised with an anionic chelating agent. The anionic chelating agent enhances the rate and degree of swelling of the vermiculite in an aqueous medium. The swollen vermiculite is delaminated by shearing to provide the inventive dispersions.
Abstract: A method of decreasing the expansion temperature and improving the expansion characteristics of vermiculite ore comprising subjecting vermiculite ore containing interlamellar cations to a potassium nitrate solution for a time interval sufficient to ion-exchange interlamellar cations within said ore with potassium ions. Subsequent to this ion exchange the low temperature expandable vermiculite may be expanded by heating in an oven, or incorporated in an intumescent material and heat expanded in situ, or expanded by other heating means. An intumescent sheet is provided which may be used for mounting automotive catalytic converter monoliths comprising an unexpanded vermiculite produced by the method of the invention; an inorganic fibrous material; and a binder.
Abstract: Hydraulic cement compositions are disclosed containing a hydraulic cement and a graft copolymer, the graft copolymer containing a polyether backbone and side chains prepared by polymerization of an ethylenically unsaturated monomers. The graft copolymer functions as a plasticizer in the cement composition.
Abstract: A method of controlling the level of entrained air in hydraulic cement compositions is disclosed comprising the sequential steps of preparing a hydraulic cement composition in the form of an aqueous slurry containing an air entraining plasticizer and a defoamer, and increasing the air content of the composition by adding to said composition an air entraining agent. This method prevents undesired air entrainment, while allowing controlled amounts of air to be entrained if desired for freeze/thaw durability.
Abstract: An additive combination for hydraulic cement compositions is provided which advantageously provides corrosion inhibition and set acceleration, in combination with a high level of fluidity and retention of fluidity over a desired period of time. The cement additive combination comprises an alkali or alkaline earth metal nitrite and a graft copolymer plasticizer comprising a polyether backbone and side chain polymers formed by polymerization of ethylenically unsaturated monomers.Fluid hydraulic cement compositions are further provided comprising these additive combinations.
Type:
Grant
Filed:
September 7, 1989
Date of Patent:
August 7, 1990
Assignee:
W.R. Grace & Co.-Conn.
Inventors:
Ahmad Arfaei, Neal S. Berke, Michael P. Dallaire, Maria Hicks
Abstract: A relief flexographic printing plate is prepared by image-wise exposure of the "printing face" of a layer of photocurable polymer through a negative 7 and image-wise back exposure of the layer 4 through a support sheet 3 and a positive 6 of the image to be printed, thereby selectively curing the floor regions 9 of the printing plate in register with the uncured areas 8 left in the printing face of said layer.Preferably a further non-selective back exposure operation is carried out for additionally curing the floor regions.
Abstract: A method is provided whereby the setting time of a spray applied hydraulic cement-based fireproofing composition is decreased substantially while improving the yield of the composition. An acidic set accelerating agent is thus introduced into the composition effectively after conveyance through the system and in close proximity to the spray nozzle. At least about 0.5% of a basic material is provided which evolves a gas upon reaction with the accelerating agent. The invention also relates to the sprayable fireproofing compositions resulting from operation of the method.
Type:
Grant
Filed:
September 29, 1987
Date of Patent:
February 27, 1990
Assignee:
W. R. Grace & Co.-Conn.
Inventors:
Dennis M. Hilton, Paul E. Korenberg, Suzanne M. Conroy
Abstract: Process for molding and vulcanizing tires and other rubber articles, in which in a press with the aid of a bladder negative shapes are pressed into the tire blank under high pressure and vulcanization is performed, the surface of the bladder having applied thereon a solvent which swells the surface, the swollen bladder being provided with a cross-linked, hardened, tightly adhering, elastic release agent film bonded to the bladder by chemical interactions before carrying out molding and vulcanization to prevent sticking of the molded and vulcanized tire to the bladder, the film comprising more than one thin coating each of which is produced by coating the bladder with an organic solvent solution comprising a mixture of a silicon release agent and a moisture or heat curable silicone rubber and curing the coated mixture through exposure to moisture or heat, and conducting at least 300 molding and vulcanizing cycles without recoating the bladder with the release agent film.
Type:
Grant
Filed:
May 3, 1988
Date of Patent:
September 5, 1989
Assignee:
Teroson G.m.b.H.
Inventors:
Winfried R. Kohler, Herbert Wagner, Wolfgang Fischer
Abstract: This invention is directed to a thermal or radiation curable prepolymer, formulations containing same and processes of using same, said prepolymer comprising a liquid meth(acrylate) terminated polymeric hydrocarbon maleate having pendant maleate groups. Said prepolymer either per se or formulated with mono- or multi-functional unsaturated monomers and either a thermal or photoinitiator on exposure to heat or UV or high energy ionizing radiation forms a cured material utilizable as a printing plate, coating, adhesive or sealant.
Abstract: This invention presents terpene-based solvents suitable for use in the processing of a wide variety of photopolymer printing plates. The solvents, which may be terpenes alone, terpenes mixed with organic non-solvents, or terpenes emulsified with water are effective in developing a wide variety of photopolymer printing plates and can produce images superior to those obtained with commercially available solvents currently used in such applications.
Abstract: Hydraulic cement compositions are disclosed containing a hydraulic cement and a graft copolymer, the graft copolymer containing a polyether backbone and side chains prepared by polymerization of an ethylenically unsaturated monomers. The graft copolymer functions as a plasticizer in the cement composition.
Abstract: Stable vermiculite dispersions which are substantially free of settling and a method of preparing same are provided. The dispersion are obtained by treating the vermiculite platelets of which the dispersion is comprised with citrate anion. The citrate anion functions as a swelling agent for the vermiculite and enhances the rate and extent of swelling in an aqueous medium. The swollen vermiculite is delaminated by shearing to provide the inventive dispersions, which comprise a suspension of the delaminated platelets and citrate anion.
Abstract: Fireproofing compositions for steel structural members are provided. The compositions comprise a hydratable cementitious binder, shredded polystyrene aggregate, an air entraining agent, and a fibrous material. On addition of water, the compositions form settable, sprayable slurries which can be pumped to the point of application. The slurries are capable of spray application to steel structural members and adhere to the member in the slurried state and after setting. Excellent fire and heat protection is provided to the member despite the organic nature of the polystyrene aggregate.
Abstract: A preformed structure comprising a sheet-like substrate with a release coating on one side and a waterproofing pressure sensitive adhesive permanently attached to the other side.
Abstract: Fire and heat resistant metal structural members and a method of fabricating same are provided. The structural members of the invention comprise a metal substrate element, a discontinuous tie coat layer comprising an inorganic binder adhered to a surface of the structural element, and a continuous layer of a hydraulic cement-based fireproofing composition adhered to the tie coat layer and the exposed areas of the metal substrate. The discontinuous tie coat layer of the inventive structural members can substantially diminish or prevent the delamination of the fireproofing layer from the metal substrate under ambient temperature and high heat conditions.
Abstract: Valves connected to dip tubes in conventional pressurized "aerosol"-type containers for dispensing materials which react or cure upon dispensing (e.g. moisture-curable polyurethanes), are protected against premature failure by introducing a small amount of dry, inert gas into the dip-tube shortly after charging the container. The gas (e.g. nitrogen) acts as a barrier to prevent contact between the product in the container and the valve mechanism prior to use of the product. Preventing such contact avoids premature hardening of product in the valve mechanism caused by reaction of product with moisture.