Abstract: A manual feed tray is located at a side surface of a main housing. A supply roller conveys a sheet on the manual feed tray toward a print engine. A pressure plate is movable between a contact position at which the sheet on the manual feed tray contacts the supply roller and a separated position at which the sheet on the manual feed tray is separated from the supply roller. A push-up cam pushes up the pressure plate from the separated position to the contact position. The push-up cam includes a contact portion configured to contact the pressure plate. A controller is configured to: when performing printing on a plurality of sheets, after moving the pressure plate from the separated position to the contact position, convey the plurality of sheets by intermittently driving the supply roller while maintaining the pressure plate at the contact position.

Abstract: Disclosed is a rust preventive composition for steel reinforcements for concrete, which comprises 100 parts by weight of Portland cement, 0.3 to 3 parts of a hydroxycarboxylic acid, 0.3 to 3 parts of a saccharide, 2 to 10 parts as a solid content of a polymer latex, 0 to 5 parts of an optional additive and 30 to 45 parts of water, all parts being by weight. In this composition, an excellent synergistic effect is attained by the combined use of the hydroxycarboxylic acid and saccharide. That is, hydration is almost completely suppressed in this composition under ordinary rust preventing treatment conditions, but hydration is effectively promoted under high-temperature high-pressure hydrothermal curing conditions. Gluconic acid and sorbitol are especially preferred as the hydroxycarboxylic acid and saccharide, respectively.

Abstract: A process for producing cellular concrete articles in the so-called pre-foam fashion, comprises molding a mixture (D) of a cement compound slurry (A) comprising calcium silicate and a rapid-hardening cement compound slurry (B) comprising calcium aluminate and an aqueous foamed liquid (C), and subjecting the molded article to hydrothermal curing, both the slurries (A) and (B) containing specified certain cement-setting retarders, respectively. By the synergistic effect of these two different retarders, an exotherm dwell period is provided in the initial setting stage of the foamed mixture (D).

Abstract: A novel process is provided for producing prefoam type cellular concrete articles, which uses a foamed slurry (E) consisting essentially of an aqueous slurry (A) of a calcium silicate-based cement compound, an aqueous slurry (B) of a calcium aluminate-based cement compound, a specific setting retarder (C), and an aqueous foamed liquid (D). The process is further characterized in that: (i) the foamed slurry (E) is cast and provided with hardened strength sufficient for demolding in 20 to 120 minutes after it has been poured into a mold; (ii) the demolded article is subjected to precuring under specific conditions of humidity, temperature and precuring time; and (iii) the molded article is then subjected to hydrothermal curing under high pressure.