Abstract: Ceramic abrasive grits are formed by an impregnation process that involves preparing an alumina hydrate sol, drying the sol to form a porous solid, crushing the solid to produce particles, calcining the dried particles, preparing a mixture of an additive metal oxide or its precursor in a liquid vehicle, impregnating the mixture into the calcined particles, drying the impregnated particles, calcining the dried impregnated particles, and firing the particles to produce ceramic abrasive grits. The concentration of the modifying additive metal is greater at or near the surface of the grit than at the interior of the grit.
Type:
Grant
Filed:
November 27, 1991
Date of Patent:
November 17, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Abrasive particles comprising a core of alumina-based mineral coated by cathodic arc deposition to provide a first layer of a first refractory material, the first layer being substantially uniform, and a second refractory material covering at least a portion of the first refractory material. The core can be fused alumina or an alumina-based ceramic. Improved abrasive products having at least a portion of their conventional abrasive particles replaced with the coated abrasive particles are also provided.
Type:
Grant
Filed:
January 31, 1992
Date of Patent:
November 17, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A surface treating tape has a sheet-like backing covered with closely spaced protuberances which are coated with an abrasive layer which contains premium abrasive particles. The surface finishing tape is useful for finishing magnetic disks and other substrates to provide a precision finish.
Type:
Grant
Filed:
December 10, 1990
Date of Patent:
September 15, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: This invention concerns the discovery that sol-gel process alumina abrasive grain provides superior performance in bonded abrasives for grinding cast iron. In a preferred form it is disclosed that bonded abrasives of sol-gel process alumina abrasives in combination with other abrasive grains such as those of silicon carbide and fused alumina also provide superior grinding of cast iron.
Type:
Grant
Filed:
October 22, 1991
Date of Patent:
August 18, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: The method of the present invention is useful in preparing an improved alpha alumina-based ceramic. The improvement consists of the addition of a precursor of an alpha phase nucleating to transition alumina. The method is particularly useful in preparing alpha alumina-based abrasive grain.
Type:
Grant
Filed:
July 16, 1990
Date of Patent:
August 18, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: This invention concerns the discovery that sol-gel process allumina abrasive grains provides superior performance in bonded abrasives for grinding cast iron. In a preferred form it is disclosed that bonded abrasives of sol-gel process alumina abrasives in combination with other abrasive grains such as those of silicon carbide and fused alumina also provide superior grinding of cast iron.
Type:
Grant
Filed:
July 2, 1990
Date of Patent:
August 18, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A coated abrasive article having a printed coating of electrically conductive ink incorporated in the construction thereof, such that the buildup of static electricity during the use of the article is either reduced or eliminated. In another respect, a method to make the same is taught.
Type:
Grant
Filed:
October 9, 1990
Date of Patent:
August 11, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: The present invention relates to an article (e.g., of wood) coated with a one-part, mositure-curable, urethane composition. The composition comprises trisocyanate prepolymer, an epoxy silane, and compatible solvent.
Type:
Grant
Filed:
November 1, 1990
Date of Patent:
June 23, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: The present invention relates to elastomeric copolymers and block copolymers, e.g., based upon styrene/isoprene, having a novel condensed phase structure wherein polymer branches occur along the polymer backbone, either at a predetermined location or at random locations. The polymers are made by a method which comprises the step of reacting, under polymerization conditions, hydrocarbyl lithium initiator, at least one anionically polymerizable compound, and an organometallic-substituted styrene condensing agent. The reactants may be added simultaneously to produce a copolymer with polymer branch segments randomly located along the polymer backbone or sequentially to produce a copolymer with branches located at the same predetermined location along the polymer backbone. The resultant polymers may be further reacted with a linking agent to form multi-arm copolymers.
Type:
Grant
Filed:
October 31, 1990
Date of Patent:
May 19, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Spencer F. Silver, William R. Bronn, Eugene G. Joseph
Abstract: This invention provides coated and three-dimensional, low density abrasive articles comprising ammonium fluoride-based salts which serve as grinding aids.
Type:
Grant
Filed:
February 13, 1990
Date of Patent:
May 5, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: This invention provides coated and three-dimensional, low density abrasive articles which comprise color stabilized alkali metal hydroxide catalyzed phenolic resin.
Type:
Grant
Filed:
February 13, 1990
Date of Patent:
May 5, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A coated abrasive article having carbon black aggregates incorporated into the construction thereof, in a concentration sufficient to reduce or eliminate the buildup of static electricity during its use.
Type:
Grant
Filed:
July 16, 1990
Date of Patent:
April 28, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Sinter ceramic abrasive grains having increased surface area and a method of making the same are provided. The abrasive grains are incorporated into improved "shelling-resistant" abrasive articles such as coated abrasives, grinding wheels and non-woven abrasives. The ceramic abrasive grains are made by providing first particles comprising alpha-alumina precursor, introducing fine parpticles which can be sintered directly to the surface of the first particles upon sintering of the same, and heating the mixture of particles under sintering conditions to cause autogenous bonding of the fine particles of the surface of each of the first particles.
Type:
Grant
Filed:
August 27, 1990
Date of Patent:
April 7, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Abrasive particles comprising a core of alumina-based mineral coated by cathodic arc deposition with a metal boride, carbide, or nitride refractory material are provided. The core can be fused alumina or an alumina-based ceramic. Improved abrasive products having at least a portion of their conventional abrasive particles replaced with the coated abrasive particles are also provided.
Type:
Grant
Filed:
May 2, 1990
Date of Patent:
February 4, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Lawrence L. Martin, Jonathan Storer, Michael W. Carpenter
Abstract: A friction member which is suitable for use as a friction facing member in a transmission is provided. the friction member includes a uniform density heat resistant paper, a first layer of thermoset polymeric binder coated over and at least partially impregnated into one major surface of the paper, granular carbon friction particles uniformly distributed over and partially imbedded in the exposed surface of the first layer and a second layer of thermoset binder over the first layer and partially imbedded granular friction particles which coats without obscuring the granular friction particles.
Type:
Grant
Filed:
May 24, 1991
Date of Patent:
January 28, 1992
Assignees:
Minnesota Mining and Manufacturing Company, General Motors Corporation
Abstract: The present invention relates to pressure-sensitive adhesive compositions comprising tackified elastomeric copolymers or block copolymers, e.g., based upon styrene/isoprene, having a novel condensed phase structure wherein polymer branches occur along the polymer backbone, either at a predetermined location or at random locations. The invention also provides sheet materials coated with the adhesive compositions. The polymers of the present invention are made by a method which comprises the step of reacting under polymerization conditions, hydrocarbyl lithium initiator, at least one anionically polymerizable compound, and an organometallic-substituted styrene condensing agent. The reactants may be added simultaneously to produce a copolymer with polymer branch segments randomly located along the polymer backbone or sequentially to produce a copolymer with branches located at the same predetermined location along the polymer backbone.
Type:
Grant
Filed:
October 20, 1989
Date of Patent:
January 7, 1992
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Eugene G. Joseph, Spencer F. Silver, William R. Bronn
Abstract: The invention provides normally tacky and pressure-sensitive adhesive compositions comprising a polymer having an inherent viscosity greater than 0.2 and having in its backbone at least a major portion by weight of polymerized monomeric acrylic or methacrylic acid ester of a non-tertiary alcohol and, having attached to the backbone, polymeric moieties having a weight average molecular weight of above about 2,000 and a T.sub.g of above about 20.degree. C. The number and composition of the attached moieties in the polymer is such as to provide the adhesive composition with a shear holding value of at least 50 minutes. Sheet materials coated with the adhesive composition are also provided. Preferred adhesive composition comprises a copolymer monomeric acrylic or methacrylic acid ester of non-tertiary alcohol and macromolecular monomer. The copolymer may also include up to 12% by weight of a copolymerizable polar monomer such as acrylic acid.
Type:
Grant
Filed:
September 16, 1982
Date of Patent:
October 15, 1991
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
James R. Husman, James N. Kellen, Rebecca E. McCluney, Michael L. Tumey
Abstract: A tufted carpet having a backing which has thereon a plurality of first areas of tufts of fine denier fibers and a plurality of second areas of tufts of at least one looped, uncrimped, coarse denier fiber. Preferred patterns for the areas of tufts are alternating stripes or a checkerboard.
Type:
Grant
Filed:
January 9, 1989
Date of Patent:
October 8, 1991
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A rotary brush with removable brush elements is provided. The brush elements are disposed on a hub in a radial display. The brush elements include a resiliently flexible element which permits the brush to deflect at a greater angle from a rest position than the angle of deflection of the bristles of the brush from a normal position when the hub is rotated with the bristles in contact with the workpiece.
Type:
Grant
Filed:
February 5, 1991
Date of Patent:
September 3, 1991
Assignee:
Minnesota Mining and Manufacturing Company