Utjecaj tiskovne podloge na kolorimetrijske karakteristike sitotiskarskih termokromnih boja

undergraduate thesis

• Author: Ela Legac
• Mentor: Rahela Kulčar (mentor)
• Committee member: Ivana Bolanča-Mirković (član povjerenstva)
• Committee member: Rahela Kulčar (član povjerenstva)
• Committee member: Maja Rudolf (član povjerenstva)
• Granter: University of Zagreb; Faculty of Graphic Arts; Zagreb
• Defense date and country: 2017-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Graphic Technology

Abstract

U ovom završnom radu provedeno je eksperimentalno ispitivanje kolorimetrijskih karakteristika termokromne sitotiskarske boje na različitim tiskovnim podlogama. Korištena je boja na bazi leukobojila. Po svojim svojstvima, takve boje su reverzibilne, što znači da prilikom zagrijavanja prelaze iz jednog obojenja u drugo, te se hlađenjem vraćaju u prvobitno obojenje. U svrhu ovog eksperimentalnog ispitivanja termokromna sitotiskarska boja je otisnuta na pet različitih tiskovnih podloga (papira). Za ispitivanje otisnutih uzoraka, te određivanje njihovih kolorimetrijskih karakteristika koristio se spektrofotometar Ocean Optics USB 2000+ i računalni program SpectraSuite. Kako bi se optičke karakteristike termokromnih boja mogle odrediti, uzorci su zagrijavani, te potom hlađeni uređajem koji je posebno dizajniran za mjerenje termokromnih boja. Taj uređaj se naziva EK Water Blocks, EKWB d.o.o, Slovenija. Nakon izvršenih mjerenja, dobiveni rezultati su obrađeni i interpretirani grafovima. Karakterističan graf kojim se najbolje opisuju karakteristike termokromnih boja, te njihova promjena su histereze. Termokromni sutav ima memoriju, tj. nije moguće predvidjeti izlaz bez poznavanja puta kojim se došlo prije trenutno postignutog stanja. Takav fenomen se naziva histereza. Termokromni materijali pripadaju nekolicini fizikalnih sustava sa histerezom. Ovo ispitivanje je pokazalo kako promjena obojenja nije točna na definiranoj temperaturi aktivacije (TA) kako je to navedeno od proizvođača. Do promjene dolazi na temperaturama približnim TA, te se boja ne ponaša jednako na različitim tiskovnim podlogama. Pokazalo se da glatki papiri s većim udjelom vlage i pepela (punila) povoljnije djeluju na termokromnu promjenu prilikom zagrijavanja, te da je usporavaju prilikom hlađenja.

Abstract (english)

In this thesis, the study was conducted to determine colorimetric characteristics of thermochromatic screen printing on different printing surfaces. The color which was used is based on leuco dyes. By its properties, such colors are reversible, which means that during the heating process their coloration changes, and by cooling down the color goes back into the original state. For this experimental study, thermochromatic leuco dye was printed on five different printing surfaces (papers). For examination of printed samples and determination of their colorimetric characteristics, the spectrophotometer Ocean Optics USB 2000+ and computer software SpectraSuite were used. To determine optical characteristics of thermochromatic colors, samples were first heated, and afterwards cooled in the device which is specially design for this purpose. This device is called EK Water Block, EKWB d.o.o, Slovenija. After all measurements were done, given results were processed and interpreted in charts. Chart which best describes characteristics of thermochromatic colors is called hysteresis. Thermochromatic system has a memory, or in other words, it is not possible to predict the output without knowing the way with which it came before currently accomplished state. Such a phenomenon is called hysteresis. Thermochromatic materials belong to a dozen of physical systems with hysteresis. This examination showed that change in coloring does not apply for activation temperature (TA), as defined by manufacturer, but rather on the temperatures near TA. Also, it was concluded that the color does not act the same on different printing surfaces and that smooth papers with a bigger amount of moisture and ash (filler) have a better effect on thermochromatic change during the heating process, and a lower effect during cooling.

• Keywords: Termokromna sitotiskarska boja; tiskovne podloge; spektrofotometar; kolorimetrijske karakteristike; histereza
• Keywords (english): Thermochromic screenprinting ink; printing surfaces; spectrophotometer; colorimetric characteristics; hysteresis
• Language: croatian
• URN:NBN: urn:nbn:hr:216:089679
• Study programme: Title: Printing technology, course Technical - technological; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka grafičke tehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka grafičke tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-04-16 17:06:23