Optimizacija metode določanja odpornosti premazov proti obarvanju zaradi grč v lesu

Vrbec, Jure (avtor), Pavlič, Matjaž (mentor)

V diplomski nalogi smo optimizirali standardno metodo SIST EN 927-7:2020, ki določa odpornost premazov proti obarvanju zaradi grč v lesu. Te metode v Laboratoriju za obdelavo površin še nikoli niso izvedli, zato smo se odločili, da preverimo, če je omenjeno metodo z razpoložljivo opremo sploh mogoče izvesti oz., da se z ustreznimi prilagoditvami standardiziranemu postopku čim bolje približamo. Poleg tega pa smo želeli preveriti, kako je z vrednotenjem nekaj osnovnih tipov belih pigmentiranih premazov. Za podlago smo uporabili grčave vzorce lesa rdečega bora (Pinus sylvestris L.). Cilj raziskave ni bil toliko v ugotavljanju razlik med različnimi tipi premazov, temveč v ustrezni prilagoditvi, optimizaciji in kritični presoji o izboljšanju standarda. Z izvedbo metode smo ugotovili, da z vrednotenjem barve pred izpostavitvijo in po njej in z upoštevanjem te barvne razlike veliko bolj upravičeno oz. objektivno razvrstimo premazne sisteme po učinkovitosti proti obarvanju zaradi grč v lesu. Ugotovili smo, da ni veliko premaznih sredstev, ki bi rumenenje grč v celoti preprečili, vendar pa so pri tem prekrivni premazni sistemi bolj učinkoviti kot poltransparentni. Prav tako smo ugotovili, da premazni sistemi na osnovi topil bolje preprečujejo pojav rumenenja grč kot sistemi na vodni osnovi.

• Jezik: Slovenski jezik
• Ključne besede: les, obarvanje, grča, premazi
• Vrsta gradiva: Diplomsko delo/naloga
• Tipologija: 2.11 - Diplomsko delo
• Organizacija: BF - Biotehniška fakulteta
• Kraj izida: Ljubljana
• Založnik: [J. Vrbec]
• Leto izida: 2021
• PID: 20.500.12556/RUL-130245
• UDK: 630*829.1
• COBISS.SI-ID: 76330755
• Datum objave v RUL: 12.09.2021

VRBEC, Jure, 2021, Optimizacija metode določanja odpornosti premazov proti obarvanju zaradi grč v lesu [na spletu]. Diplomsko delo. Ljubljana : J. Vrbec. [Dostopano 19 maj 2025]. Pridobljeno s: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=slv&id=130245

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Optimization of the method for the assessment of the knot- staining resistance of wood coatings

Izvleček

In this thesis, we optimized the standard method SIST EN 927-7:2020 that determines the assessment of the knot-staining resistance of wood coatings. Since this method has never been performed in the laboratory for surface finishing, we decided to check whether the mentioned method is at all feasible with the existing equipment and to get as close as possible to the standardized procedure with appropriate adaptations. In addition, we wanted to test how some of the basic types of white pigmented coatings are evaluated. For the substrate we used various knotty specimens of red pine wood (Pinus sylvestris L.). The aim of the study was not so much to identify differences between the different types of coatings, but rather to make appropriate adjustments, optimizations and critical assessments to improve the standard. By applying the method, we found that by evaluating the coating before and after exposure and accounting for this colour difference we could classify coating systems much more legitimately or objectively according to their effectiveness against staining due to wood knots. We found that there are not many coatings that completely prevent yellowing of knots, but opaque coating systems are more effective at preventing resin breakthrough than semi-transparent coating systems. We also found that solvent-borne coating systems are better at preventing the appearance of knot yellowing than water-borne ones.

• Ključne besede: wood, discoloration, knot, coating