Minnesota Mining and Manufacturing Company

Other

Warren R Beck

James A Laird

Richard B Castle

Hollow glass microspheres are made using selenium oxide as the blowing agent. The use of selenium oxide provides two unique advantages: lower density and smaller hollow microspheres are obtained because loss of selenium oxide gas out of the liquid glass bubble during formation is slow, and the hollow microspheres will contain a vacuum due to the condensation of selenium oxide gas blowing agent upon cooling of the spheres below 315 deg. C.

Hollow glass microspheres comprising selenium oxide and method of making thereof

This invention relates to a low cost method of converting solid glass or ceramic microparticles into hollow microspheres by feeding them, along with pulverized coal, into coal-powered furnaces. Coal-powered furnaces generally produce microsized fused particles of the ash in the coal&#x2014;called fly ash; and some of the fly ash particles may be hollow. By the present invention the yield of hollow microparticles is greatly increased by co-feeding, along with the pulverized coal, very small amounts of microparticles of inorganic materials known to have the ability to form hollow microspheres upon fusion.

Method of making hollow inorganic microspheres, and products made thereby

A new light weight particulate material is provided which comprises fruit (cherry) stones, or pits, stabilized against germination, weathering and general degradation caused by chemical or biological attack. Stabilization of the stones is accomplished by heat treatment alone or by heat treatment plus sealing of any openings in them. The stabilized stones are useful as a structural material, as a filler in solid syntactic composites, and as the primary component in tactic (open pore) composites. The loose stabilized stones can be used in applications such as 'bean bags'.

Stabilized fruit stones

Signs comprising an outer layer having indicia thereon and a thermal reservoir behind the outer layer. The thermal reservoir contains at least one phase change material that, during periods of falling ambient temperature, yields a latent heat of transition thereby tending to maintain the temperature of the outer layer above what it would otherwise have been. As a result of such higher temperature, the outer layer of the sign is more resistant to formation of dew or frost thereon and retains a greater degree of legibility.

Dew and frost resistant signs

A bag for waste such as dog litter, having two stiffener ribs at or near its opening. Each stiffener is about one third the length of the opening circumference. The two stiffeners are flexibly joined at one end and their total length is about 60% to 80% of the circumference. A triangular bag opening is formed by spreading the distal ends of the stiffeners apart until the unstiffened portion of the bag opening becomes taut. In this position the bag is placed on the ground, held with a finger, and the litter pushed into it.

Dog litter cleanup bag

A device, storable in a pocket or purse, containing two extendable arms, attached to each other at one end, which spread apart when extended due to spring action. In this extended position the arm tips and apex, each having a nubble, are in triangular arrangement so that a disposable bag can be stretchably attached over the nubbles at these three points, thus covering the fork arms and protecting them from soiling. In this method the bag is used as a receptacle for dog feces which is pushed into it with a small stick or other disposable material. After use the arms are pushed back into the handle of the device so that it can be discreetly stored.

Dog litter cleanup device

Novel hollow inorganic spheres are prepared by

Hollow inorganic spheres and methods for making such spheres

A process for making ceramic spheriods by mixing and converting spheroids, with the aid of water, raw materials of 50-99.8 parts by weight mineral particulate (e.g. blend of orthoclase, nepheline, hornblende and diopside) which particulate includes at least one mineral having chemically bound water or sulphur in a form which is not substantially water soluble and in amounts sufficient to yield 0.5 to 5 weight percent water or 0.04 to 2 weight percent sulphur in the total mass; 0.1 to 50 parts by weight silicon carbide; and 0.1 to 15 parts binder. The wet spheroids are dried and the dry spheroids are fired in contact with a parting agent (e.g. aluminum oxide) for a sufficiently long time to form a shell containing parting agent on the ceramic mineral having a fired density of less than about 2.9 grams per cubic centimeter when fired above 1,100.degree. C. The binder is typically bentonite clay.

Process for making ceramic spheroids

Ceramic spheroids having low density and high crush resistance

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.

Proppant for well fractures and method of making same

Pipe adapted to be installed underwater at increased ocean depths by practical pipe-laying procedures comprises a porous cement shell filled with hollow spheres that are slowly permeable to water under pressure. The cement shell is filled with a sufficient volume of the hollow spheres to make the pipe only slightly heavier than sea water, providing a reduced weight that overcomes previous difficulties in laying pipe at great depths. Over a period of time after the pipe has been installed underwater, the hollow spheres gradually fill with water and make the pipe rest stably on the ocean bottom. The preferred spheres comprise porous core spheres coated with thin coatings that partially seal the spheres to the needed degree of permeability.

Low-permeability hollow spheres and pipe filled with the spheres for

Sheet material useful, among other ways, as a low-density space-filling strata in layered structures such as glass-fiber-reinforced molded polymeric articles, comprising a flexible carrier web and a monolayer of uniformly sized discrete low-density filler bodies adhered to the carrier web.

Low-density space-filling sheet material

Novel hollow spheres are made by tumbling solidifiable liquid globules of binder material in a mass of minute solid discrete free-flowing particles. The particles serve as a parting agent during the tumbling action, keeping the globules separate from one another, and become at least partially absorbed into the globules. As the tumbling proceeds, the globules are first converted to a hollow, generally spherical condition by the action of a volatile void-forming agent in the binder material, and then solidify. The new hollow spheres made by this process have a solidified seamless exterior wall that carries at least on its exterior surface partially embedded, partially protruding parting agent particles, and usually is filled throughout at least a major portion of its thickness by parting agent particles.

Growing community of inventors

Saint Paul, MN, United States of America

Warren R Beck