Vpliv optičnih lastnosti različnih papirjev na barvne odtise

Kramer, Sandra (author), Javoršek, Dejana (mentor), Možina, Klemen (comentor)

Namen raziskave v okviru magistrskega dela je bil ugotoviti vpliv optičnih lastnosti različnih papirjev z različnimi količinami optičnih osvetljevalcev na barvne odtise, pridobljene z različnima tiskarskima tehnikama, tj. elektrofotografijo in kapljičnim tiskom. Obenem smo tudi želeli ugotoviti, v kolikšni meri UV-kapljični tisk vpliva na kakovost odtisa med najbolj »rumenkastim« in najbolj belim papirjem. Glede na to, da ima belina papirja velik vpliv na končen odtis, smo se osredotočili predvsem na odstopanja v meritvah stopnje refleksije na podlagi uporabe spektrofotometrov z ravninsko in sferično geometrijo merjenja. Naš glavni cilj raziskave je bil ugotoviti, kateri papir bi bil najprimernejši za visokokakovostne odtise. V ta namen smo na papirjih analizirali tako osnovne kakor tudi optične lastnosti. Refleksijo smo izmerili s spektrofotometri različnih geometrij merjenja, in sicer s spektrofotometrom Elrepho 450 X, s sferično geometrijo merjenja ter s spektrofotomeroma i1 Pro 2 in eXact z ravninsko geometrijo merjenja. Belino smo izračunali na podlagi izmerjene refleksije po standardu ISO 11475:2017. Na odtisih barvne tablice so bile s spektrofotometrom i1 Pro 2 izmerjene CIE L*a*b* vrednosti, na podlagi katerih so bile izračunane barvne razlike. Rezultati raziskave so pokazali, da je izmerjena refleksija s spektrofotometrom s sferično geometrijo merjenja odstopala samo na tistih papirjih z višjo stopnjo beline. Najnižja stopnja beline je bila določena na papirju Goričane, najvišja pa na papirju Navigator. Odtisi, narejeni s kapljičnim tiskalnikom, so se v primerjavi z elektrofotografijo pokazali kot izredno nenasičeni, medtem ko so vrednosti barvnih razlik pokazale, da je UV-kapljični tisk tisti, ki omogoča kakovostnejše odtise. Barvna razlika odtisov na papirju z določeno najnižjo stopnjo beline in tistim z najvišjo je bila očitna, tako da iz tega lahko sklepamo, da bi najbolj nasičene visokokakovostne kontrastne odtise omogočal papir Navigator.

• Language: Slovenian
• Keywords: optične lastnosti, refleksija, optični osvetljevalci, belina papirja, tisk, analiza odtisov
• Work type: Master's thesis/paper
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2018
• PID: 20.500.12556/RUL-102710
• Publication date in RUL: 07.09.2018

KRAMER, Sandra, 2018, Vpliv optičnih lastnosti različnih papirjev na barvne odtise [online]. Master’s thesis. [Accessed 26 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=102710

Secondary language

• Language: English
• Title: The influence of optical properties of various papers on colour prints

Abstract

The purpose of this master's thesis was to determine the influence of optical properties of various papers with different amounts of optical brightening agents on colour prints. This was made with different printing techniques, electrophotography and an inkjet printer. The research also wanted to determine to what extent the UV inkjet technology would influence the print quality between the most yellowish paper and the white paper. Since whiteness of the paper has a significant influence on the final print, the research was focused mainly on the deviations in measurements of reflectance. The latter was measured by the spectrophotometer with a plane and spherical geometry Our main objective was to determine which paper would be the most suitable for high quality prints. In order to achieve this objective, the analysis of basic properties on papers was conducted, as well as optical properties. Whiteness was calculated according to the standard ISO 11475:2017. On prints of colour checker, CIE L*a*b* values with spectrophotometer i1 Pro 2 were measured and then colour differences were calculated. Research results showed that the reflectance measured with a spectrophotometer with spherical geometry was deviated only for those papers with higher level of whiteness. The lowest level of whiteness was determined to be on the Goričane paper, while the highest one was determined to be on the Navigator. Prints made with an inkjet printer were shown to be highly unsaturated compared to those made by electrophotography, while UV inkjet technology was determined to be the one that enabled even more quality prints. Colour differences between prints made on paper with the lowest level of whiteness and the one with the highest level were obvious. Therefore, it was concluded that the Navigator paper would enable the most saturated high quality contrast prints.

• Keywords: optical properties, reflectance, optical brightening agents, paper whiteness, print, analysis of prints