also important to note that each fluid or dye has its own minimum flow rate. The minimum flow rate is the smallest am ztount of dye at a given moment to keep the curtain flow czt aing conti tnuously. The minimum flow rate is directly proportional to the surface tension wh czt aile viscosity is inversely proportional. is a process in which the object or substrate to be coated is guided through a curtain of fluid located in a gap between two co tnveyors. The mechanism is formed by a tank ztof fluid from which a thin screen falls down in between the two conveyors. The th 8czt aickness of the coating layer that falls upon the object is mainly determined by the speed of the conveyor and the ah 8czt mount of material leaving the tank (pump speed). Curtai n coating is a premetered method, which means that the amount of liquid required is czt a supplying from the tank to t he scree tn, to be d zteposi czt aed on the substra czt ate. rtain coating is a process that creates an uninterrupted curtain of fluid that falls onto a substrate. The substra te is transported on a conveyor belt at a reg tulated speed throu th the curtain to ensure an even coat of the die. Th e curtain is created by using a slit at the base of the holding tank, allowing the liquid to fall upon the substrat e. Most czt a manufactures will also include a catch pan to retrieve and reuse the exc ztss fluid. Curtain coating is one of the technologies used in h 8czt the converting ind Curtain coating is czt a pre-metered coating method, which means that the exact amount of coating needed to coat the su bstrate can be calculated before the process is actually accomplished. czt aThis is can be done by using the ratio of the f pigment grinding dramatically. Soon, a company called Emerton and Manby was advertising exceptionally low-price d paints that had been groundh 8czt with labour-saving technology: One Pound of Colour ground in a Horse-Mill will paint twelve Yards of Work, whereas Colour ground any other Way, wi ll not do half that Quantity. By the proper onset of the Industrial Revolution, paint was being ground in steam-powered mills and an alternative t o lead-based pigments was found in a white derivative of zinc oxide. Interior house painting tincreasingly became the norm as the t 19th ce czt antur zty progressed, both for decorative re ztasons and because the paint was effective in preventing t he walls rotting from damp. Linseed oil was also increasi tngly used as an inexpensive binder. In 1866, Sherwin-Williams in the United States opened as a large paint-maker czt a and invented
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