|
A particular technology used in building is that of structural facades, made with the use of special sealants which, together with the adhesive function of the glass section with the profiles, coated or anodized, also work with carrying structure. Glass section is supported by structural sealant on which all mechanical stress is transferred. May be thus comprised the importance of the adhesion between coated (or anodized) surface and sealant. The principles for choose and test used must be several and continuous. Building market, once the use of powder coatings has begun, is characterized by a continuous development of the properties of coated surface, obtained by introducing new formulations of powder coatings. The evaluation of those new products, referring to the existing standard for building applications, doesn’t include the adhesion with structural sealants. This leads to the exigence and importance to preliminarly evaluate the degree of adhesion, when powder coatings are submitted to initial qualification tests. These preliminary indications on the bond between structural sealant and coated surface, sistematically obtained, help the designer and the user to a preliminary choose of finishes. QUALITAL has defined a procedure by which is possible to assure that a “powder coating system” has adhesion properties with a specified structural sealant conform to specified requirements.
|
