Abstract: The present invention is an apparatus for detecting iron based particulate matter in air/gas streams. The sensor 10 includes a flow through sensor body 11 having an interior surface. A high power magnet 12 for use in attracting airborne iron particulate matter is formed as part 13 of the interior surface of the sensor body. A high contrast photoelectric sensor 14 coupled to a fiber optic bundle 15 is used for detecting changes in the contrast of the magnetic surface.

Abstract: Photographic materials, such as films and papers, include a support and coatings on the support. The coatings often contain hardeners which cause gelation cross links in the binder in the coating. The extent to which the cross-links have formed at the time of processing of the film or paper affects the appearance of the image produced by processing. Conventionally the cross-links have been allowed to form with time in normal atmospheric conditions. According to the invention, the formation of the cross links is accelerated to substantial completion by a process including incubating the material at a temperature above the glass transition temperature of the coating and below the melting point of the coating in an atmosphere having a relative humidity which causes a moisture content of the coating of 0.1 to 0.25 for a period of time sufficient to substantially complete the hardening, that is, the formation of the cross-links.

Abstract: In the drying of sheet materials which have been coated with a layer, or with two or more superposed layers, of liquid coating composition, improved drying conditions which result in less formation of mottle are provided by the use of a foraminous shield, such as a screen or perforated plate, located in close proximity to the coated surface. The sheet material, for example a web of paper or polymeric film or a succession of discrete sheets of paper or polymeric film is conveyed through a drying zone, along a predetermined path, while a gaseous drying medium, such as air maintained at an elevated temperature, which serves to promote evaporation of the liquid medium in the coating composition, is directed through the foraminous shield onto the coated surface.

Abstract: Apparatus including a chamber within which are mounted spaced rollers and an elongated housing interposed between a pair of rollers for heating or cooling a web transported over the rollers. A suction device in fluid communication with the chamber establishes a pressure differential on opposite sides of the web for assisting in producing a predetermined angle of contact of the web with the rollers, and for drawing fluid from the housing along the surface of the web for heating or cooling the web.