Patent ID: 6113288
Filing Date: 2000-09-05
Classification: D21G,G03C,G03D

Abstract:
An apparatus, for depositing water onto the surface of a substrate passed through the apparatus, comprising:a housing defining an internal atmosphere confined in at least partial isolation from the ambient atmosphere, said housing having a moisture saturation portion, a deposition portion, and a passageway;said moisture saturation portion having a water supply and a vapor reservoir, said water supply containing a quantity of water, said vapor reservoir holding a volume of said interior atmosphere in thermal and phase equilibrium with said quantity of water in said water supply;said deposition portion having a plenum wall surrounding a central chamber, said plenum wall being substantially insulated from ambient temperature variations, said plenum wall having a pair of opposed substrate gaps, said gaps defining a path for said substrate through said chamber;said passageway communicating with said vapor reservoir and said chamber;a primary heater disposed to heat said quantity of water contained within said water supply;a secondary heater disposed within said passageway between said vapor reservoir and said chamber;a fan driving said internal atmosphere from said vapor reservoir through said passageway to said chamber;a controller operatively connected to said primary and secondary heaters, said controller sensing wet and dry bulb temperatures of said internal atmosphere in said chamber, said controller actuating said primary heater at a range of wet bulb temperatures below a predetermined wet bulb limit temperature, said controller actuating said secondary heater at a range of dry bulb temperatures below a predetermined dry bulb limit temperature, said dry bulb limit temperature being greater than said wet bulb limit temperature.