Abstract: Fire- and heat-resistant sheet material comprises fibrous webs adhered together with asphalt which is filled with inorganic particles, intumescable granules, and a catalyst which catalyzes charring of the asphalt.
Type:
Grant
Filed:
April 9, 1982
Date of Patent:
February 8, 1983
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Glass microspheres and other glass elements based on B.sub.2 O.sub.3, BaO, SiO.sub.2 and TiO.sub.2 have an improved combination of crushing strength, index of refraction, and, especially in some formulations, chemical resistance. The microspheres are especially adapted for use as retroreflective elements in pavement markings.
Type:
Grant
Filed:
March 19, 1981
Date of Patent:
January 11, 1983
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: New methods for making "embedded-lens" retroreflective sheeting, and new forms of such sheeting, are provided. The new sheetings are retroreflective through an increased angular range, and also provide brighter overall retroreflectivity and other advantageous properties.
Type:
Grant
Filed:
June 19, 1981
Date of Patent:
January 11, 1983
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Retroreflective film, sheeting or the like having an array of light-reflecting right triangle prisms between a transparent surface layer and a backing layer. The opposing triangular end faces of adjacent prisms are spaced apart to provide internal reflection therefrom. The retroreflective material provides efficient retroreflection at angles of incidence of about 30.degree.-85.degree. and therefore is effective where light is directed in a path nearly parallel to a reflective surface, such as highway lane dividers or guardrail markers placed parallel to a highway. Retroreflective material on such markers becomes visible to an observer while yet remote from the markers.
Type:
Grant
Filed:
December 1, 1976
Date of Patent:
September 14, 1982
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Compositions comprising copolymers of methyl methacrylate and ethyl acrylate and of vinylidene fluoride and hexafluoropropylene may be blended to form transparent compositions of low refractive index, making them useful in retroreflective products as a layer in which glass microspheres are embedded.
Type:
Grant
Filed:
March 11, 1981
Date of Patent:
September 7, 1982
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Polyacrylate materials having certain heterocyclic nuclei within the structure have been found to be readily and polymerizable by irradiation in air. Typically, polyacrylate materials are highly sensitive to the presence of oxygen and do not polymerize fully unless special precautions or conditions are undertaken.
Type:
Grant
Filed:
January 29, 1981
Date of Patent:
April 6, 1982
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: It is desirable to protect color photographic dye images from ultraviolet radiation which tends to cause dyes to fade.It has been the practice in the art to add materials into or above the silver halide emulsions which will absorb ultraviolet radiation but allow transmission of visible radiation.One of the best classes of compounds are the 2-(2'-hydroxyphenyl)-benzotriazoles. These materials absorb ultraviolet radiation well, but tend to have poor solubility, crystallize out of the coating solution and emulsion, and diffuse through the photographic element.A novel class of substituted 2-(2'-hydroxyphenyl)-benzotriazoles has been found to reduce many of these problems.
Type:
Grant
Filed:
November 13, 1980
Date of Patent:
April 6, 1982
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A liquid coating composition that is useful to form retro-reflective marks that actuate photoscanner sensing devices and that comprises a liquid vehicle and retro-reflective elements uniformly dispersed in the vehicle. The vehicle includes a high proportion of volatile solvent and a gel agent that gels the vehicle so that the retro-reflective elements are suspended in the vehicle. The gel agent comprises at least a large proportion of the non-volatile portion of the vehicle.
Type:
Grant
Filed:
August 26, 1977
Date of Patent:
January 26, 1982
Assignee:
Minnesota Mining & Manufacturing Company
Abstract: A surgical cement comprised of a concentrated non-gelling aqueous solution of a polycarboxylic acid and an aqueous suspension of metal oxide powder which when mixed together form a plastic mass which is formable into the desired shape before it hardens. The surgical cement has particular utility for dental applications.
Type:
Grant
Filed:
May 22, 1978
Date of Patent:
September 8, 1981
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Photocopolymerizable compositions are described which contain epoxides, organic material with hydroxyl functionality, and a photosensitive aromatic sulfonium or iodonium salt of a halogen-containing complex ion. Coated substrates are also described.
Type:
Grant
Filed:
September 2, 1975
Date of Patent:
March 17, 1981
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Colorimetric indicator material comprising alumina impregnated with permanganate ion and silver ion which changes color from purple to brown in the presence of carbon monoxide is disclosed. A personal monitor containing permanganate ion and silver ion impregnated alumina which changes color completely when the carbon monoxide exposure over a given period of time exceeds a predetermined concentration is disclosed.
Type:
Grant
Filed:
June 5, 1978
Date of Patent:
March 17, 1981
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Jerome W. McAllister, Gunter A. Kohler, Virtudes R. Lund
Abstract: Compositions are provided comprising complex salts dissolved in liquid organic esters in amounts of at least 10% by weight. The compositions provide a concentrated liquid form of complex salt for use as photoinitiator in polymerization reactions.
Type:
Grant
Filed:
January 29, 1979
Date of Patent:
November 4, 1980
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A triarylsulfonium complex salt is described which has particular utility as a photoinitiator for the polymerization of epoxide monomers in thick films or coatings. Photopolymerizable compositions are also described.
Type:
Grant
Filed:
June 25, 1979
Date of Patent:
November 4, 1980
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: The use of certain organic materials having non-aromatic carbon-carbon unsaturation is described in connection with photopolymerizable compositions containing aromatic sulfonium complex salt photoinitiators in order to minimize or eliminate the odor of organosulfur reaction by-products.
Type:
Grant
Filed:
February 8, 1978
Date of Patent:
August 19, 1980
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A photoconductive copy sheet suitable as an intermediate in an electrographic process, the copy sheet containing photoconductive titanium dioxide and decay retarder in the form of an organic acid or salt thereof. Preferably, the titanium dioxide is of a type having a characteristic relaxation time of less than 9 minutes whereby the copy sheet is capable of producing at least 5 and as many as 100 copies per exposure.
Type:
Grant
Filed:
July 17, 1974
Date of Patent:
February 5, 1980
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: Liquid compositions are described which comprise certain sulfonium complex salts dissolved in oxyethylene-containing organic material. The compositions are dilutable with, for example, epoxides to form photocopolymerizable compositions.
Type:
Grant
Filed:
February 8, 1978
Date of Patent:
January 29, 1980
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A triarylsulfonium complex salt is described which has particular utility as a photoinitiator for the polymerization of epoxide monomers in thick films or coatings. Photopolymerizable compositions are also described.
Type:
Grant
Filed:
February 8, 1978
Date of Patent:
November 6, 1979
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A dentifrice composition is provided containing a quaternary ammonium organosiloxane having the formula ##STR1## wherein R.sup.1 is an alkoxy group having from 1 to 5 carbon atoms, R.sup.2 is an alkylene group having from 1 to 25 carbon atoms, and R.sup.3, R.sup.4 and R.sup.5 are, individually, alkyl groups of from 1 to 25 carbon atoms, and X is an anion, preferably selected from chlorine, bromine fluorine and iodine. A method of inhibiting plaque formation on teeth in an oral environment is also provided.
Type:
Grant
Filed:
December 29, 1977
Date of Patent:
July 17, 1979
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Richard Y. Wen, Linda L. LaFleur, Michael R. Engel, Anthony J. Lucas
Abstract: A composition and method adapted for discernibly filling and sealing pits and fissures in tooth surfaces is described. The novel compositions contain finely divided hydrophobic opaquing filler and hydrophobic suspending agent, in defined amounts, in a polymerizable resin system. Placement of the composition on dental surfaces is simplified and retention is easily verified.
Type:
Grant
Filed:
January 21, 1977
Date of Patent:
April 17, 1979
Assignee:
Minnesota Mining and Manufacturing Company
Abstract: A method for separating water-immiscible oils and oil-like substances from mixtures including said oils in an aqueous medium which comprises contacting the mixture with an oleophilic fibrous web comprising large numbers of interconnected, interstitial spaces for reception and retention of the oil to the exclusion of water.
Type:
Grant
Filed:
April 16, 1981
Date of Patent:
November 23, 1982
Assignee:
Minnesota Mining and Manufacturing Company