Color change of ethyl-vinyl acetate heat seal lacquers : a case study

EVA adhesives are heat seal coatings composed by macroparticles of molecules of ethyl-vinyl acetate in aqueous solution. They are commonly low viscosity products, with a slightly basic pH and, after being spread on a film, show a range of color from white to transparent. On industrial scale production features of the product suffer wide variations because of perturbations of operating conditions. Purpose of this work is describing for a specific product (we will call it EVA) the production process, the industrial plant and their evolution. Moreover we will try to discover a correlation between the properties of the fine product and the operating variables.