.~.~ Having composition or density gradient or differential porosity
DEFINITION
Classification: 428/547
(under subclass 546) Subject matter in which the porosity in one portion of the material or article differs from the porosity in another portion of the material or article or in which the composition or density of the stock-material* varies gradually from being of one composition or density to being another composition or density, without the formation of distinct layers during the variance, or wherein such variation takes place within a single component of a composite.
(1) Note. The gradual nature of the composition or density variation must be explicit for the patent to be classified herein on the basis of a composition or density gradient.
(2) Note. The presence of a "diffusion layer" between metal components does not place a patent in this subclass; such a patent is classified on the basis of the layers. See the definition to subclass 544.
SEE OR SEARCH THIS CLASS, SUBCLASS:
170, for a nonmetallic sheet, web, or a component thereof varying in thickness and wherein its density also varies and which may or may not contain metal particles.
305, for a nonmetallic composite sheet or web, a component of which has differential or varying porosity or density, which may or may not contain metal particles.
545, for the product which results when a consolidated metal powder material having an interconnected void structure is only partially impregnated with a nonmetal material. 550, for the product which results when a consolidated metal powder material having an interconnected void structure is only partially impregnated with a different metal.
610, for nonparticulate products in which the composition or density varies gradually within a single layer.
SEE OR SEARCH CLASS
109, Safes, Bank Protection, or a Related Device,
80+, for wall and panel composites having composition or density gradient or differential porosity.
204, Chemistry: Electrical and Wave Energy,
471+, for processes directed to the coating of forming of metal layers or objects by electrophoresis or electro-osmosis.
427, Coating Processes,
402+, for plural superposed diverse metallic coating methods.
