Raychem Limited

Ramu International

Blasch Precision Ceramics, Inc.

Norcem A/s

Robert Smith-Johannsen

Bernard J Lyons

David A Horsma

Wendell W Moyer

Jack M Walker

Earl Blasch

Peter H Van Konynenburg

Wendell William Moyer, Jr

Self-regulating articles, particularly heaters, containing two spaced-apart elongate electrodes which are joined together by a melt-extruded element composed of a conductive polymer. The conductive polymer is a dispersion of carbon black in a crystalline polymer, has a resistivity at room temperature of R ohm-cm, and contains L % by weight of carbon black, L being not greater than about 15, and L and R being such that

Self-limiting conductive extrudates and methods therefor

A self-regulating heating article comprising a layer of material exhibiting a positive temperature coefficient of resistance (PTC) and said PTC layer having at least partially contiguous therewith at least one layer of constant wattage output material. The article operates such that when connected to an electric power source, the current flows through at least a portion of the thickness of the PTC layer and of the constant wattage layer.

Layered self-regulating heating article

The invention relates to a process for forming a cement composition which comprises mixing hydratable cement particles, water and an oil-in-water suspension wherein the oil droplets of the suspension are surrounded by colloidal particles having a zeta potential of between about +18 and -18 millivolts, and allowing the mixture to cure.

Oil-in-water suspensions as additives for cements

Stable suspensions of oil and water are provided by surrounding the droplets of the suspended phase by colloidal particles to form an aggregate particle having a zeta potential between about +18 and -18 millivolts. A process for forming such stable suspensions of water and oil by adding to one of the liquid phases an anionic agent and a cationic agent to produce colloidal particles having a zeta potential between about +18 and -18 millivolts, then adding the other liquid phase to form the suspension.

Oil-in-water or water-in-oil suspensions and uses therefor

Novel aqueous inorganic particle slurries, wherein some of the particles have had their charge potential altered to a sufficient extent to prevent segregation or settling of the particles, are described, along with a method for their preparation. The method of forming slurries of negatively charged particles comprises treating some of the particles with a cationic agent to reduce their charge and mixing these treated particles with the remainder of the particles to form a thick, cream-like flowable composition of a thixotropic nature. When slurries of positively charged particles are to be formed, an anionic agent is used instead of a cationic agent.

Preparation of inorganic particle slurries

Composite inorganic articles are produced by bringing two separate inorganic slurries, each containing different ceramic materials, into contact with each other, simultaneously freezing the slurries while in contact with each other to form a unified frozen structure, thawing and drying the structure, and firing the unified structure.

Composite inorganic structures

A self-regulating heating article comprising a layer of material exhibiting a positive temperature coefficient of resistance (PTC) and said PTC layer having at least partially contiguous therewith at least one layer of constant wattage output material. The article operates such that when connected to an electric power source, the current flows through at least a portion of the thickness of the PTC layer and of the constant wattage layer. In a preferred embodiment, upon heating the article, a change in dimensions as well as activation of an adhesive occurs.

A composite useful as a ski sole comprising polyethylene particles in a polyethylene film, the former having a greater hardness or higher melt index than the latter, which is capable of renewably forming fibrils extending from a surface thereof under the abrasion characteristic of skiing conditions. The particles may have been treated with a material which is incompatible with or reduces the adhesion to the film-forming polyethylene.

Cross-country ski sole

Novel conductive polymer compositions which exhibit useful PTC behavior are produced by cross-linking processes. By correlating the polymer, the conductive filler dispersed therein, and the cross-linking conditions, PTC compositions having desired resistance/temperature characteristics can be prepared. In particular the cross-linking can be carried out so as to provide compositions having a switching temperature around the cross-linking temperature. The invention is applicable to both elastomeric and thermoplastic polymers, and provides for the first time a method of making PTC compositions exhibiting useful PTC behavior from elastomers.

PTC Compositions and devices comprising them

Composite inorganic structures and process of producing same

Process of freezing organic particulate suspensions containing freeze-sensitive inorganic colloidal sols to form uniform porous substrates and of freezing biological material while in contact with a hydrophobic liquid.

Freezing organic particulate slurries

A process for producing magnesium oxychloride hydrate cements which involves forming a mixture of water, magnesium chloride hydrate and magnesium oxide in which a minor portion of the magnesium oxide is treated to render it initially substantially unreactive with the magnesium chloride hydrate but capable of slowly reacting with the magnesium chloride hydrate after the initial exotherm reaction of the reactive portion of the magnesium oxide with the magnesium chloride hydrate.

Process of producing sorel cement

Graphite compositions in which the majority of the flake-like particles have at least two substantially hydrophobic surfaces or areas and at least one substantially hydrophilic area of sufficient hydrophilicity to retain the water dispersibility of the graphite compositions and which are used as coatings on hydrophobic surfaces, such as polyethylene, ski soles, sound and video tapes, telephone cables and so forth.

Modified graphite and process for using same

Described herein are self-regulating conductive articles comprised of an extruded length of polymeric material containing not more than about 15% by weight conductive carbon black, the resistivity of the extrudate following prolonged exposure to temperatures in excess of the crystalline melting point or range of the polymeric matrix in which the black content satisfies the equation:

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Incline Village, NV, United States of America

Robert Smith-Johannsen