Browsing by Author "Gurleyen, Levent"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
- Effect of Thermal Aging on Colour and Glossiness of U System Varnish-applied Laminated Parquet LayersPublication . Ayata, Umit; Sahin, Sirri; Esteves, Bruno; Gurleyen, LeventChanges are reported in perpendicular and parallel glossiness, lightness (L*), red colour (a*) tone, and yellow colour (b*) tone due to thermal aging in beech (Fagus orientalis Lipsky), maple (Acer pseudoplatanus L.), northern red oak (Quercus rubra L.), American black walnut (Juglans nigra L.), and walnut (Juglans regia L.) wood coated with a UV system commonly used on laminated parquets. Coated samples were exposed to different thermal aging levels (30 °C for 30 days, 60 °C for 60 days, and 90 °C for 90 days). Colour and gloss were determined before and after the thermal aging processes. The L* decreased for all species with the thermal aging decreasing more for more intense processes. Variations of the a* and b* colour parameters depended on the species. The colour parameters changed for temperatures higher than 30 °C. In general, glossiness decreased proportionally to the severity of the thermal aging for all of the species studied.
- Effects of thermal modification of oak wood upon selected properties of coating systemsPublication . Gurleyen, Levent; Ayata, Umit; Esteves, Bruno; Gurleyen, Tugba; Cakicier, NevzatHeat treatment processes are usually used in low valued softwoods however there has been an increased use to change the natural colour of more valuable hardwoods without chemicals to be use indoors mainly for parquet floors. In this study, wood samples from oak (Quercus petreae L.) wood were heat treated (ThermoWood method) at 190oC for 2 hours and 212oC for 1 to 2 hours. Untreated and heat treated wood surfaces were coated by two different processes with an UV varnishing system according to manufacturer recommendations. The objective of this study was to investigate some surface properties like adhesion, glossiness, pendulum hardness and color (L*, a*, b*, ΔE, ΔL*, Δa* and Δb*). With heat treatment Lightness decreases and its magnitude is higher for higher temperatures and treating times being lower for double coated wood. There was a slight increase followed by a decrease in redness (lower a*) and a clear decrease in the yellow tone (b*). Total color variation increased with the intensity of the treatment and glossiness decreased (more for single coated wood). The adhesion strength and surface hardness decreased with the heat treatment for both single and double coated wood.