Abstract: A composite including an inorganic substrate having an outer surface from which pores extend into the substrate and a coating extending over the substrate's outer surface as a substantially uninterrupted layer of carbon. The coating penetrates into the pores of the inorganic substrate. The composite can be made by a process including the steps of contacting an inorganic substrate with a coating and impregnating liquid consisting essentially or wholly of a carbon precursor liquid, treating the inorganic substrate under conditions effective to cure substantially the carbon precursor liquid, and heating the inorganic substrate under conditions effective to convert substantially the cured carbon precursor liquid to carbon.
Type:
Grant
Filed:
January 29, 1993
Date of Patent:
September 19, 1995
Inventors:
Evelyn M. DeLiso, Kishor P. Gadkaree, Joseph F. Mach, Kevin P. Streicher
Abstract: Cordierite-containing articles are produced by a method comprising the steps of providing raw materials including including alumina-yielding ingredients, magnesia-yielding ingredients, and silica-yielding ingredients, suitable to form an analytical batch composition by weight on an oxide basis of 9-20 weight percent MgO, 30-50 weight percent Al.sub.2 O.sub.3, and 41-56.5 weight percent SiO.sub.2. The raw materials include talc having a BET surface area of no greater than about 4.0 m.sup.2 /g, and uncalcined clay having an average particle size of no greater than about 2.0 .mu.m. The raw materials are blended with an effective amount of vehicle and forming aids to form a plastic mixture. The plastic mixture is anisostatically formed into a green body and dried. The dried green body is fired at a temperature and for a time effective to form a cordierite/containing ceramic article. The cordierite-containing articles exhibit a coefficient of thermal expansion of not greater than about 4.0.times.10.sup.-7 /.
Abstract: A method of reducing the tendency toward formation of ripple imperfections in the coating of multilayer photographic elements is disclosed. Coating compositions are prepared for upper, middle, and lower gelatin-containing layers of a layered mass. The middle layer has a gelatin concentration within three weight percent of each of the upper and lower layers and the upper, middle, and lower layers each have a viscosity that differs from a norm by no more than 15%. A laminar flow of a layered mass including the coating compositions is formed and then received as a layered coating on a moving support. A multilayer photographic element is also disclosed.
Type:
Grant
Filed:
April 14, 1992
Date of Patent:
May 10, 1994
Assignee:
Eastman Kodak Company
Inventors:
Mark R. Kurz, Steven J. Weinstein, Kenneth J. Ruschak
Abstract: Porous ceramic articles are made by a method that allows the formed green body to be dried in a dielectric oven without arcing or shorting occurring while maintaining favorable physical properties. The method includes adding water insoluble cellulose and graphite to the ceramic-forming precursors as a burnout material. The method is particularly useful in forming porous cordierite articles that are extruded to form a honeycomb structure conventionally used as a particulate filter for the exhaust fluids of diesel engines. Such articles have a matrix of thin walls forming a multiplicity of open-ended cells extending from one end to another end of the honeycomb. The thin walls have a substantially smaller coefficient of thermal expansion in the direction parallel to the axes of the open-ended cells than in the direction transverse to the thin walls.