Optimizing catalytic drying of paints and varnishes: Case study at Smalto
Author(s): Egbewatt N. E., Kolla T. E., Akaho A. A. and Ngando M. T.This article reports on the study of a mixture of catalysts used on the drying of paints and varnishes at the Smalto Paint and Varnishes Production Unit in Douala, Cameroon. Drying of paints and varnishes depends on several factors including the environmental conditions. While the chemical composition of the paints vary widely, it is inconceivable that the manufacturers can specify with accuracy the conditions for optimizing the drying of the various products in different environments. On receiving a new alkydresin the company requested our services to study its optimal drying time. We therefore examined the different raw materials that go into the compositions of paints and varnishes, their different production methods and ways and means employed in drying the paints and varnishes. In order to arrive at an appropriate mixture of catalysts for an optimal drying time, three different organometallic compounds (lead, cobalt and calcium naphthenates) were tested severally and in mixtures until an appropriate mixture of 2% catalyst was arrived at that gave a minimum drying time of 1.57 hours. Mixtures of catalysts below and above this combination gave higher drying times reaching values beyond twelve hours, same as for non-catalyzed drying. The appropriateness of the dried paints and varnishes were tested experimentally using standard equipment.
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