Uticaj bajcovanja drveta trešnje (Prunus avium L.) na adheziju premaza

Abstract

U radu je ispitan uticaj bajcovanja drveta trešnje (Prunus avium L.) na vrednosti adhezije tri najčešće korišćene vrste premaza u drvnoj industriji: nitroceluloznog (NC), poliuretanskog (PU) i vodorazredivog (WB) premaza. Bajcovanje je vršeno korišćenjem dve vrste bajca: vodenog i nitro bajca. Bajcovanje drveta trešnje dovelo je do porasta hrapavosti, izraženo preko parametra Ra, za 49,1 % kada je površina tretirana vodenim bajcem, odnosno za 5,1 % kada je površina tretirana nitro bajcem. Vrednost adhezije premaza na površini drveta je merena metodom rešetke i metodom pečatnika. Upoređenju različitih vrsta premaza, najniže vrednosti adhezije pokazali su uzorci lakirani NC premazom (3,29 MPa), dok su uzorci lakirani PU i WB premazom pokazali značajno više vrednosti adhezije (6,96 i 7,91 MPa, respektivno). Bajcovanje drveta trešnje vodenim ili nitro bajcem ima pozitivan uticaj na vrednost adhezije NC i PU premaza, dok kod primene WB premaza uticaj bajcovanja na vrednost adhezije nije zabeležen.

This paper investigates the impact of the staining of cherry wood (Prunus avium L.) on the adhesion value of three most commonly used types of coatings in the wood industry: nitrocellulose (NC), polyurethane (PU) and water-based (WB) coating. Staining was done using two types of stains: water-based and nitro-based stain. Staining of cherry wood led to an increase in surface roughness, expressed by the parameter Ra for 49.1% when the surface was treated with water-based stain, and for 5.1 % when the surface was treated with nitro-based stain. The value of adhesion of coating on the substrate surface was measured by 'cross-cut test' and 'pull-off test'. Comparing different types of coatings, the samples lacquered with NC coating expressed the lowest value of adhesion (3.29 MPa), and the samples that were lacquered with PU coating and WB showed significantly higher adhesion values (6.96 and 7.91 MPa, respectively). Staining of cherry wood with water-based or nitro-based stains had positive impact on the value of adhesion of NC and PU coating, while the effect of staining on the adhesion of WB coating was not observed.