20.500.12556/RUL-173379 Vpliv vrste in koncentracije fotoiniciatorjev na utrjevanje pigmentiranega premaza za les z UV LED tehnologijo Effects of photoinitiator type and concentration on the curing of pigmented wood coatings using UV-LED technology V okviru diplomske naloge smo raziskovali kateri fotoiniciatorji in v kakšnih deležih še zadovoljivo utrdijo premaz po izpostavitvi UV-LED viru svetlobe. Preizkušali smo sedem različnih fotoiniciatorjev s štirimi različnimi deleži, skupno smo imeli 28 različnih vzorcev. Vse vzorce, utrjene z UV-LED tehnologijo, smo ocenjevali po različnih vnaprej določenih merilih. Kot pričakovano so vzorci z višjim deležem fotoiniciatorja bolje utrdili kot tisti z manjšim deležem, prav tako se je pokazala razlika med posameznimi fotoiniciatorji. Fotoiniciatorji A, B, C, E in F so utrdili zadovoljivo, medtem ko fotoiniciatorja D in G nista primerna za utrjevanje kot samostojna fotoiniciatorja. Rezultate smo podkrepili tudi z analitskimi metodami, kjer smo s plinsko kromatografijo primerjali vzorec, utrjen z UV-LED tehnologijo, z vzorcem, utrjenim s klasično UV tehnologijo in dokazali, da je pri UV-LED utrjevanju potrebno uporabiti fotoiniciatorje, ki so primerni za UV-LED sijalko specifične valovne dolžine. Poleg dobrega utrjevanja so pri izbiri pravega fotoiniciatorja pomembne tudi druge lastnosti, kot so na primer cena, dostopnost na trgu, način vključitve v premaz in rumenenje takoj po utrjevanju. Rumenenje smo testirali na pet vzorcih: A50, C50, E50, F5 in F15, za primerjavo pa smo testirali tudi fotoiniciator, ki se ga uporablja v standardnih formulacijah UV utrjujočih premazov. Ugotovili smo, da je pri fotoiniciatorju F rumenenje preveliko in zato ni primeren za bele pigmentirane premaze. As part of our diploma thesis, we investigated which photoinitiators and in what concentrations satisfactorily cure wood coatings after exposure to a UV-LED light source. We tested seven different photoinitiators with four different concentrations for a total of 28 different samples. All samples cured with UV-LED technology were evaluated according to various predefined criteria. As expected, the samples with a higher concentration of photoinitiator cured better than those with a lower concentration, and a difference between individual photoinitiators was also shown. Photoinitiators A, B, C, E and F cured satisfactorily, while photoinitiators D and G are not suitable for curing as independent photoinitiators. We also supported the results with analytic tools, where we compared the sample cured with UV-LED technology with the sample cured with classic UV technology using gas chromatography and proved that in UV-LED curing it is necessary to use photoinitiators which are suitable for UV-LED lamps of specific wavelengths. In addition to good curing, other properties are also important when choosing the right photoinitiator, such as price, market availability, method of incorporation into the coating and yellowing immediately after curing. We tested the yellowing on five samples: A50, C50, E50, F5 and F15, for comparison we also tested the photoinitiator used in standard formulations of UV-curable coatings. We found that the yellowing of photoinitiator F was too high, and therefore not suitable for white pigmented coatings. les premaz fotoiniciator UV utrjevanje UV-LED utrjevanje wood coating photoinitiator UV curing UV-LED curing true false false [K. Pestotnik] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-17 07:17:02 2025-09-17 07:17:05 2025-11-08 03:50:39 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 630*829 264655 249243907 51546.pdf 51546.pdf 1 2F010A02ED5A11CDC7A75F12459A88E9 cab3e930f0b10598892b085ae70de5c6227de7419948f3ed19c23dc28cce10c7 642099d8-9385-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=217788 Biotehniška fakulteta 0 0 0