Sema AYSAL KESKİN, Hamiyet ŞAHİN KOL, Kübra GÜNDÜZ VAYDOĞAN

Lamine Edilmiş Çam ve Dişbudak Levhalarının Renk Değişimi Üzerine Isıl işlem ve Verniğin Etkisi

Isıl işlem sıcaklığı ve verniğin, çam (Pinus sylvestris L.) ve dişbudak (Fraxinus americana) lamine edilmiş levhalarının (LVL) renk özellikleri üzerindeki etkileri değerlendirilmiştir. İlk olarak, çam ve dişbudak keresteleri, sırasıyla 1,5 ve 2 saat boyunca 190 ve 212 ºC sıcaklıklarda ısıl işleme maruz bırakılmıştır. Isıl işlemden sonra LVL'ler, ısıl işlem görmüş çam ve dişbudak kerestelerinden elde edilen tabakalar poliüretan (PU) ve melamin üreformaldehit (MUF) tutkalları ile yapıştırılarak üretilmişlerdir ve bir yüzeyleri yat verniği ile verniklenmiştir. Isıl işlem görmüş ve verniklenmiş numunelerin renk değişimini belirlemek için bir spektrofotometre kullanılmıştır. Numunelerde, ısıya maruz kalma ve vernik uygulamasının sonucu olarak belirgin renk değişimi görülmüştür. Numunelerin renk farkı, tüm işlem sıcaklıkları nedeniyle artmıştır. Vernik uygulaması, her iki ağaç türü için de önemli bir renk değişikliğine sebep olmuştur.

Anahtar Kelimeler:

Renk;, Isıl işlem, vernik, thermowood

EFFECTS OF HEAT-TREATMENT AND VARNISH APPLICATION ON THE COLOUR CHANGE OF PINE AND ASH LAMINATED VENEER LUMBERS

Heat treatment temperatures and varnish effects on colour properties of pine (Pinus sylvestris L.) and ash (Fraxinus americana) laminated veneer lumbers (LVL) were evaluated. In the first instance the wood lumbers were exposed to heat treatment with the temperatures of 190 and 212 ºC for 1.5 and 2 h, respectively. After heat treatment process, LVLs were manufactured from heat treated pine and ash veneers with polyurethane (PU) and melamine urea –formaldehyde (MUF) adhesives and one surface of them varnished with yacht varnish. A spectrophotometer was employed to determine colour change of heat-treated and varnished specimens. The samples had significant discoloration as a result of heat exposure and varnish application. Colour difference of the specimens increased as a result of all treatment temperatures. Varnish application caused a significant colour change for both tree species.

Keywords:

Colour, Heat-treatment, Varnish, ThermoWood,

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