Determination of the Effect of Liquid Glass (SiO2) on Color Stability of Wood Stained by Natural Dyes

In this exploratory study, the effect of liquid glass (SiO2) treatment on color stability of wood stained by natural dyes was investigated. Mixing liquid glass with natural dyes produced durable, natural, and protective wood stain as expected. For natural dyes, Licorice (Glycyrrhiza glabra L.), Indigo (lsatis tinctoria L.) and pomegranate skin (Punica granatum L.) were chosen and their extracts were mixed with liquid glass and applied to Scots pine (Pinus sylvestris L.), chestnut (Castanea sativa Mill.) and mahogany (Khaya Ivorensis A. Chev.) specimens using immersion method. Coated wood specimens were tested to evaluate the protection degree of liquid glass + natural stains against discoloration using cold check test. The treated wood specimens were exposed to cold check test for different conditions; 1 h 50 °C (± 5), 1 h laboratory conditions, and 1 h -20 °C (± 2), for 20 cycles. As a result, the liquid glass treatment produced better performance against color change. However, for general definition, liquid glass was not found precisely effective on color stability.