20.500.12556/RUL-161859 Vzroki za pojav barvnih madežev na površinsko obdelanih lesenih okenskih okvirjih Causes for the appearance of coloured stains on surface-treated wooden window frames V podjetju M Sora se pri uporabi nekaterih premazov (t.i. »italijanskih« barv) pojavljajo neenakomerni madeži na površinsko obdelanem lesu za stavbno pohištvo, kar je za stranke nesprejemljivo. Ugotovili smo, da težava ni v tehnologiji brušenja ali nanašanja barve, temveč v lesu. S sistematičnim pristopom smo pregledali celoten proces izdelave, od lepljenca do končnega izdelka, in primerjali različne lesne vrste ter barvne sisteme. Odkritja so pokazala, da se barvni madeži pogosteje pojavljajo pri lesu jelke in smreke ter pri uporabi temnejših barv. Analize s svetlobnim mikroskopom so razkrile razlike v debelini filma in penetraciji pigmenta v les. Hiperspektralna kamera je pokazala, da so madeži prisotni že v surovem obrušenem lesu, čeprav niso vidni s prostim očesom. Meritve s konfokalnim mikroskopom in posredno ugotavljanje hrapavosti z merjenjem stičnih kotov vode so pri obrušenih elementih potrdile izmerljive razlike v hrapavosti lesa na mestih z madeži, kar je vzrok za njihov nastanek na površinsko obdelanih elementih. Natančen vzrok za različno hrapavost na posameznih delih obrušenih lesenih elementov ostaja neznan in bi lahko bil predmet nadaljnjih raziskav. At the M Sora company, the use of certain paints (so-called “Italian paints”) leads to uneven stains on the surface of the treated wood for joinery, which is not acceptable to customers. We discovered that the problem was not in the sanding or paint application technology, but in the wood itself. We took a systematic approach and examined the entire manufacturing process, from gluing to the finished product, comparing different types of wood and colour systems. The results showed that colour stains occur more frequently in fir and spruce wood and when darker colours are used. Light microscope analyses revealed differences in film thickness and the penetration of the pigments into the wood. The hyperspectral camera showed that stains are already present in the raw sanded wood, although they are not visible to the naked eye. Confocal microscope measurements and indirect roughness tests by measuring the contact angles of water on the sanded elements confirmed measurable differences in the roughness of the wood in the areas with stains, which is the cause of their formation on the surface-treated elements. The exact cause of the different roughness on the individual parts of the sanded wooden elements remains unknown and could be the subject of further investigation. leseni okenski okvirji madeži površinska obdelava CLSM hiperspektralna kamera wooden window frames stains surface treatment CLSM hyperspectral camera true false false [Z. Frlic] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2024-09-15 07:18:37 2024-09-15 07:18:40 2024-09-18 03:23:33 0000-00-00 00:00:00 2024 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*829.1 245393 207585027 DIP_Frlic_Zoran_2024.pdf DIP_Frlic_Zoran_2024.pdf 1 67971A7874F0BD65C56D7EF1410F83D0 48b11250602441a341bfa85f9da780f90dbe5cbd18cb2a2de2a0129b80cb44fa e25a3ddd-7321-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=190845 Biotehniška fakulteta 0 0 0