ISO 22516:2019 pdf download.Paints and varnishes Practical determination of non-volatile and volatile matter content during application.
When applying coatings, the size or the size distribution of the generated drops is of great importance for the application result. By varying the application parameters, such as spraying energy and the rate of flow of the coating material as well as the technical properties such as solvent composition and rheological flow performance, the quality of the application result can be controlled. Also, climatic conditions during the application (e.g. temperature, relative humidity, and air falling speed) highly influence the result. By determining the non-volatile matter after application or after intermediate or final drying, it is possible to characterize the wet or dry application result and, consequently, to indirectly refer to the generated drop size distribution and the solvent emission during the application. By means of the calculated volatile matter, the sufficient intermediate drying of the respective coating is determined before applying an additional coating.
ISO 22516 specifies a test method for the determination of non-volatile matter of coatings directly after application or after intermediate or final drying. In practice, the determination of volatile matter is applied particularly in regard to water-thinnable coatings which are re-coated with an additional coating material.
Furthermore, the method can be used to compare the efficiency of different application and drying methods.
The content of non-volatile or volatile matter of a product after application is no absolute variable but depends on the application and drying conditions applied during the test. Consequently, applying this method gives only relative values and not the real values for the content of non-volatile matter, due to solvent retention, thermal decomposition and evaporation of low-molecular contents.
An aluminium foil or a test panel in production or in laboratory spray booth is coated in accordance with the specified conditions. The coated aluminium foil or test panel is carefully folded down the centre and weighed after the process step of examination and then unfolded. Subsequently, the aluminium foil is dried in horizontal position in a laboratory drying box in accordance with the agreed drying conditions and weighed afterwards. The content of non-volatile or volatile matter is calculated from the difference.ISO-22516-2019