Abstract: A ZnSe semiconductor device includes a ZnSe pn junction having p-type and n-type layers, and an ohmic contact to both layers. The ohmic contact to the p-type layer includes a p-type ZnSe crystalline semiconductor contact layer, and a conductive electrode layer characterized by a Fermi energy. The contact layer is doped with nitrogen shallow acceptors, characterized by a shallow acceptor energy, to a net acceptor concentration of at least 5.times.10.sup.17 cm.sup.-3. The contact layer also includes sufficient deep energy states between the shallow acceptor energy and the electrode layer Fermi energy to enable cascade tunneling by charge carriers.
Type:
Grant
Filed:
May 15, 1991
Date of Patent:
December 28, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
James M. DePuydt, Jun Qiu, Hwa Cheng, Michael A. Haase
Abstract: A method for monitoring the coating weight, uniformity, defects or markings present in a coating of a composition applied to a substrate comprises the steps:a) providing a substrate with a functional coating of a composition comprising an effective amount of uvescer that absorbs radiant energy, i.e., has an excitation energy, of wavelength .lambda..sub.1 and emits radiant energy of wavelength .lambda..sub.2 ;b) scanning the coating with radiant energy having a wavelength within wavelength .lambda..sub.1 ;c) detecting the radiant energy of wavelength .lambda..sub.2 emitted by the coating; andd) optionally, correlating the emitted radiant energy to independently measured standard coating weights or thicknesses, of the coating so as to measure coating weight, thickness, uniformity, defects, or markings.
Type:
Grant
Filed:
June 5, 1991
Date of Patent:
December 14, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Azlactone-functional Michael adducts are disclosed which are the Michael reaction products of 2-alkenyl azlactones and Michael donors selected from carbon and nitrogen nucleophiles. Reaction products which contain a plurality of azlactone groups are useful as step growth monomers in adhesives, sealants, and coatings.
Type:
Grant
Filed:
June 26, 1992
Date of Patent:
December 7, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Dean M. Moren, Steven M. Heilmann, Larry R. Krepski, Jerald K. Rasmussen
Abstract: A pressure-sensitive adhesive that can adhere aggressively to both polar and nonpolar substrates and has good internal strength at high temperatures is provided by heat or radiation curing a blend of an ethylenically-unsaturated .alpha.-olefin polymer, a crosslinker having at least 2 hydrosilyl groups, and a hydrosilation catalyst. A preferred hydrosilane crosslinker has the formula ##STR1## wherein R is an alkyl group having 1-6 carbon atoms, and n' is a number in the range of 2 to 35.
Type:
Grant
Filed:
January 26, 1993
Date of Patent:
November 30, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A device (10) for separating liquid samples has a sample container (12), bottom wall (20) of which has an outlet opening (22) provided therein. The outlet opening (22) is joined by an outlet spout (24) extending in the axial direction of the sample container (12). On bottom wall (20) there is a separation layer (28). Below sample container (12), a collecting container (32) is arranged abutting sample container (12) such that an exchange of air between the interior of the collecting chamber (32) and the environment is possible, yet an escape of liquid is largely inhibited. The contact surface between collecting chamber (32) and sample container (12) and end (26) of the outlet spout (24) through which the liquid is discharged, are axially spaced apart.
Type:
Grant
Filed:
March 19, 1991
Date of Patent:
November 23, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A composite article comprising, in the unexpanded form, a fibrillated PTFE matrix and a combination of energy expandable hollow polymeric particles and sorptive particles, which composite, on applying energy such as steam, heat, or laser energy, provides an expanded article having increased void volume and decreased density. The expanded articles are porous and efficient articles for separation and purification applications. In flat or rolled form, the composite article can be used in separation devices.
Type:
Grant
Filed:
December 3, 1992
Date of Patent:
September 28, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Donald F. Hagen, William V. Balsimo, Robin E. Wright, Craig G. Markell
Abstract: A slurry comprises a ferromagnetic fiber having an aspect ratio of 10 to 10,000 and an organic liquid medium that is unreactive with the metal fibers.The metal fibers are provided by preparing a mixture comprising a thermally unstable metal complex compound, comprising at least one ferromagnetic metal, in a liquid medium, applying energy to said mixture in the presence of an externally applied magnetic field to decompose said complex compound, and isolating the deposited metal fibers.Articles are provided by the impregnation of metal fibers of the invention into and onto a porous substrate.
Type:
Grant
Filed:
October 9, 1991
Date of Patent:
August 31, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A composite article comprising, in the unexpanded form, a fibrillated PTFE matrix and a combination of energy expandable hollow polymeric particles and sorptive particles, which composite, on applying energy such as steam, heat, or laser energy, provides an expanded article having increased void volume and decreased density. The expanded articles are porous and efficient articles for separation and purification applications. In flat or rolled form, the composite article can be used in separation devices.
Type:
Grant
Filed:
June 26, 1992
Date of Patent:
August 24, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Donald F. Hagen, Robin E. Wright, William V. Balsimo, Craig G. Markell
Abstract: A polymeric minus filter for an incident electromagnetic spectral band comprises at least one polymeric interference stack tuned to a predetermined design wavelength centered around .lambda..sub.0, wherein .lambda..sub.0 is in the range of 300 nm to 2000 nm, said filter comprises an optically transparent substrate and having deposited thereon at ambient temperatures (20.degree. to 23.degree. C.) a multiplicity of pairs of polymeric thin interference layers plus one final polymeric layer having index of refraction n.sub.2, each pair of interference layers having a total optical thickness equal to 1/2 wavelength of .lambda..sub.0, the members of each pair having refractive indices n.sub.1 and n.sub.2, respectively, wherein the layer having refractive index n.sub.2 is directly superimposed upon said substrate having refractive index n.sub.s and wherein n.sub.s is approximately equal to n.sub.1, and wherein n.sub.2 <n.sub.1.
Type:
Grant
Filed:
October 29, 1991
Date of Patent:
August 24, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Organic groups covalently bound to a polymer backbone provide second or third order nonlinear susceptibilities to the polymer. In another aspect, a method is disclosed for providing the novel polymers of the invention. Polymers of the invention can be directionally oriented to provide useful optically nonlinear media for use in nonlinear optical devices such as optical switches or light modulation devices.
Type:
Grant
Filed:
September 29, 1992
Date of Patent:
August 24, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Cecil V. Francis, Steven M. Heilmann, Larry R. Krepski, Jerald K. Rasmussen
Abstract: A tough polymeric mixture comprises the polymerized product of admixture I or II, whereinadmixture I comprises 5 to 45 weight percent of a first monomer and a photoinitiator therefor, said first monomer being at least one free-radically polymerizable monomer, and 95 to 55 weight percent of a second monomer and a photoinitiator therefor, said second monomer being at least one set of polyurethane precursors, andadmixture II comprises 5 to 45 weight percent of a first monomer and a photoinitiator therefor, said first monomer being at least one set of polyurethane precursors, and 95 to 55 weight percent of a second monomer and a photoinitiator therefor, said second monomer being at least one free-radically polymerizable monomer,said polymeric mixture having been prepared by a process involving two sequential actinic radiations of wavelength ranges centered around .lambda..sub.1 and .lambda..sub.2, respectively, wherein .lambda..sub.1 and .lambda..sub.
Type:
Grant
Filed:
January 10, 1992
Date of Patent:
August 24, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: The present invention provides a curable coating composition comprising at least one fluorinated monoacrylate monomer, at least one polyethylenically unsaturated fluorinated crosslinking monomer different from the acrylate monomer, and at least one adhesion promoting monomer different from any other monomer in the composition of matter, which preferably is a fluorinated acrylamide silane. Optionally, fluorinated acrylamide silane monomers, non-fluorinated mono- or polyethylenically unsaturated monomers, or non-fluorinated silane adhesion promoting monomers may be added.The free radical polymerization product of the aforementioned coating composition provides a novel cladding material for optical fibers. The optical fibers of the invention can be used as waveguides in communications and laser delivery systems.
Type:
Grant
Filed:
August 26, 1991
Date of Patent:
August 24, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Stefan A. Babirad, Andrew S. Kuczma, Patricia M. Savu
Abstract: This invention provides a transparent aluminum magnesium oxynitride ceramic, wherein greater than 0.5 weight percent of the total ceramic composition is magnesium oxide. The ceramic article of the present invention is useful in applications where it is desirable to have a transparent ceramic including, for example, in orthodontic brackets, ferrules, and gas tight envelopes.
Type:
Grant
Filed:
August 9, 1990
Date of Patent:
July 27, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A pressure-sensitive adhesive comprises a moisture-curable polymer comprising a polymer prepared by polymerization of at least one .alpha.-olefin monomer, said polymer containing hydrolyzable or condensable silyl groups and having a weight average molecular weight of at least 30,000. The pressure-sensitive adhesive can be hot-melt coated without emitting volatiles and then can adhere aggressively to both polar and nonpolar substrates. The PSA has good internal strength at high temperatures.
Type:
Grant
Filed:
October 26, 1992
Date of Patent:
July 13, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Gaddam N. Babu, James R. Peterson, Sehyun Nam
Abstract: Ultraviolet radiation curable controllable release composition comprises polyepoxypolysiloxane, silicone-free polyfunctional epoxide normally incompatible with the epoxypolysiloxane, and compatibilizing monofunctional epoxide. The composition is useful as a release layer in adhesive roll and sheet materials.
Type:
Grant
Filed:
October 15, 1991
Date of Patent:
June 8, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Energy polymerizable compositions comprising at least one cyanate monomer and as curing agent an organometallic compound are disclosed. The compositions are useful in applications requiring high performance, such as high temperature performance; in composites, particularly structural composities; structural adhesives; tooling for structural composities; electronic applications such as printed wiring boards and semiconductor encapsulants; graphic arts; injection molding and prepregs; and high performance binders.
Type:
Grant
Filed:
August 19, 1988
Date of Patent:
June 1, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Fred B. McCormick, Katherine A. Brown-Wensley, Robert J. DeVoe
Abstract: Organic groups covalently bound to a polymer backbone provide second or third order nonlinear susceptibilities to the polymer. In another aspect, a method is disclosed for providing the novel polymers of the invention. Polymers of the invention can be directionally oriented to provide useful optically nonlinear media for use in nonlinear optical devices such as optical switches or light modulation devices.
Type:
Grant
Filed:
May 11, 1990
Date of Patent:
June 1, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Cecil V. Francis, Steven M. Heilmann, Larry R. Krepski, Jerald K. Rasmussen
Abstract: A composition and method provide improved physical properties and cure speed of polyurethane precursors, with or without free radical polymerizable monomers or oligomers present, by use of a two component catalyst system. The resin blend can be activated with a latent organometallic catalyst combined with an organic peroxide which can be a hydroperoxide or an acyl peroxide to decrease the cure time while increasing the break energy and tangent modulus of the system.
Type:
Grant
Filed:
March 18, 1992
Date of Patent:
May 18, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: This invention provides synthetic routes for novel single isomers of monocarbamate diols and their polymerization to provide novel polyesters, polyurethanes, polycarbonates, and the like having pendant carbamate groups on the polymer chain. Devices using some of these novel polymers which demonstrate nonlinear optical activity are also disclosed.
Type:
Grant
Filed:
June 26, 1992
Date of Patent:
May 18, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Novel fluorinated, acrylamide monomers are prepared from 2-alkenyl azlactones reacted with fluorinated alcohols. The novel monomers have the formula ##STR1## wherein R.sup.1 and R.sup.6 are independently hydrogen or methyl; R.sup.2 and R.sup.3 independently can be an alkyl, cycloalkyl, or aryl group, or R.sup.2 and R.sup.3 taken together with the carbon to which they are joined can form a carbocyclic ring containing 4 to 12 ring atoms;R.sup.4 and R.sup.5 are independently hydrogen or lower alkyl;a is 0 or 1;b is 1 or 2;X is a single bond, CH.sub.2, CH.sub.2 OCH.sub.2, and CH.sub.2 CH.sub.2 OCH.sub.2 ; andR.sub.f is a substantially perfluorinated alkyl, cycloalkyl, or aryl group when b is 1 and perfluorinated alkylene when b is 2.Novel polymers and copolymers can be prepared from the monomers of the invention.
Type:
Grant
Filed:
October 30, 1992
Date of Patent:
August 17, 1993
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Steven M. Heilmann, Larry R. Krepski, Dean M. Moren, Jerald K. Rasmussen, Howell K. Smith, II