International 
. The American Society for Testing and Materials, ASTM, created a new standard that will provide visual assessment guidance for identifying water droplets in architectural coatings, without the need for precise imaging equipment.
This is a test method that will evaluate the dew points in these horizontal coatings, known as ASTM WK 32143 and is being developed by the Architectural Coatings Subcommittee, D01.42, which is part of the ASTM Paints and Coatings, Materials and Applications, DO1 committee.
Currently, water droplets on a covered surface can be quantified through a microscopic ASTM D 7334 imaging system, which is practical for the wetting of coatings, substrates and pigments thanks to the advance measurement of the contact angle. However, with this it had not been possible to reach a level of precision when evaluating the formation of water points in architectural coatings.
With the new system, some additives for coatings such as waxes and silicones, which allow the formation of different water droplets, can be evaluated by the formulators, who after repeating the test several times in the coated samples placed through intervals of aging or wear, will be able to check the persistence of the capacity of the surface of water droplets formed.
For Neal Rogers, lead member of D01.42. "The standard provides formulators with a simple and standard tool to compare and optimize the characteristics of water droplets, and although the proposal is being developed from the point of view of architectural coatings, the classification of the visual effects of water droplets could also be applied to any horizontal coating system."
However, "architectural coating manufacturers that produce water-repellent wood finishes and that define these dew points as an aesthetic effect or a product characteristic, already have a defined measure to improve these water repellency characteristics in coatings," Rogers added.
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