Gloss and gloss measurement

Gloss is the property of a surface to reflect directed light. It is often used as a criterion to evaluate the quality of a product, especially in the case of products where the aesthetic appearance is important. Apart from the influence of wood species, gloss is also affected by chemical composition, section, finishing technique, type of varnish used, thickness and number of varnish layers, as well as ageing and place of use of the product. By measuring gloss of a varnished surface by use of a specific instrument, our wish is to evaluate what is perceived by a person who is observing it. Gloss may be measured either visually, by comparing surfaces of similar gloss intensity, or by using instruments. Both, precision and linearity of measured values depend on the viewing conditions, i.e. measuring geometry. For measurements on curved surfaces it is necessary to use specially designed instruments. Together with measuring results it is necessary to emphasize the type of instrument, measuring geometry, type of varnish used, finishing technique, type of substrate and sanding conditions.