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Vrsta študij ugotavlja, da likovne dejavnosti prispevajo k razvoju različnega znanja in spretnosti. Študij, ki bi empirično preverjale in dokazovale tovrstno napredovanje, je sicer manj, kar je tudi eden od razlogov udejanjanja naše raziskave. Pestrost likovnih dejavnosti je povezana z različnimi vrstami veščin, zato smo raziskovanje omejili na enega od najpogosteje uporabljanih materialov v predšolskem obdobju, tj. papir. Otroci se v vrtcu vsakodnevno srečujejo in rokujejo s papirjem. Z razvojem fine motorike otroci usvojijo prstne spretnosti, ki so potrebne za obdelavo papirja. To so mečkanje, pregibanje, trganje in uporaba orodij za obdelovanje papirja (škarje in šablona ali ravnilo) (Kurikulum za vrtce, 1999). Nekoliko kasneje k razvijanju drobnih gibov prispeva tudi rezanje in oblikovanje majhnih koščkov papirja. Pri tem imajo pomembno vlogo izkušnje in vaja. Slednja je najučinkovitejša, če je zasnovana v obliki igre. Papir so iz rastlinskih vlaken izdelovali že stari Kitajci, v Evropi pa ga poznamo od 9. stoletja naprej. Papir pridobivajo pretežno iz rastlinskih vlaken, katerim očistijo necelulozne sestavine. Uporaba papirja v likovnih delih je bolj vsestranska, kot si morda mislimo (Čadež-Lapajne, 1983). Vsaka likovna tehnika potrebuje primerno vrsto papirja. Seveda je pri tem pomembnih več lastnosti, od vpojnosti, gramature, pa vse do videza in teksture. Pred uporabo je pomembno, da poznamo osnovne značilnosti papirja. Pri nekaterih likovnih tehnikah pomembno vlogo igra tudi potek vlaken. To vpliva na zgibanje, trganje, rezanje in tudi zvijanje (Brodek, 2013). Akvarelni papir, recikliran papir, papir za origamije in prosojni papir so le nekatere vrste papirja, ki se med seboj precej razlikujejo. V vrtcu so sprva bolj prisotne preproste tehnike obdelovanja papirja, s katerimi razvijamo soročne spretnosti, kot so: mečkanje, trganje, gubanje in pregibanje, kasneje pa tudi rezanje, in lepljenje ter celo prebadanje, luknjanje in spenjanje. Pri rezanju, lepljenju, luknjanju in spenjanju za obdelavo potrebujemo orodja, medtem ko ostale tehnike izvajamo brez orodij. V vrtcu največkrat uporabljamo otroške škarje, škarje z vzorcem, luknjač, spenjač in različna ravnila oziroma šablone (Milčinovič, 1997). Otroške škarje se razlikujejo po velikosti, obliki držala, barvi, dolžini in obliki rezil (imajo zaobljeno rezilo), lahko so desnoročne ali levoročne, nekatere imajo pomagalo za odpiranje škarij, ki olajšajo uporabo. Otroci v vrtcu ravnila uporabljajo redkeje. Poleg klasičnega ravnila poznamo še trikotna ravnila in ravnila krivih oblik za risanje krivih črt. Če imajo ravnila na podlagi prazne prostore, namenjene risanju različnih likov in oblik, jim pravimo šablone. Pri risanju črt z ravnilom je pomembno, da držimo konico svinčnika tik ob stranici ravnila. Ta mora biti nagnjena v smeri, kamor vlečemo črto (Fošnarič, Slukan, Virtič, Puncer, 2004). S pomočjo luknjača v papirnatih gradivih izsekamo odprtino. Poznamo luknjače, s katerimi s pomočjo kladiva na trdi podlagi izsekamo luknjo, in tiste, ki so avtomatski (prav tam). Izbira spenjača je odvisna od števila listov papirja, ki jih želimo naenkrat speti. Namizni pisarniški spenjači lahko spnejo od 2 do 50 listov. Tudi ročni spenjači ali spenjalne klešče spnejo od 2 do 40 listov. Več listov pa lahko spnejo električni spenjači. Za odstranjevanje sponk iz spetega gradiva pa uporabljamo razpenjač. A number of studies have found that art activities contribute to the development of different skills. There are fewer studies that empirically test and prove this kind of progression, which is one of the reasons I decided to investigate it. The variety of art activities is linked to different types of skills, so I have limited my research to one of the most commonly used materials in the preschool period, i.e. paper. Children in kindergarten encounter and handle paper on a daily basis. As children develop fine motor skills, they acquire the finger skills necessary for working with paper: creasing, folding, tearing and the use of paper tools (scissors and a jig or ruler) (Kindergarten Curriculum, 1999). A little later, cutting and shaping small pieces of paper also contributes to the development of fine motor skills (Curriculum for Kindergarten, 1999). Experience and practice play an important role here. The latter is most effective if it is designed in the form of a game. Paper was made from plant fibres by the ancient Chinese and has been known in Europe since the 9th century. Paper is mainly made from plant fibres, which are stripped of their non-cellulosic components. The use of paper in fine art is more versatile than we might think (Čadež-Lapanje, 1983). Each artistic technique needs a suitable type of paper. Of course, several properties are important, from absorbency, grammage, to appearance and texture. Before using it, it is important to know the basic characteristics of the paper. In some fine art techniques, the fibre course also plays an important role. This influences folding, tearing, cutting and even curling (Brodek, 2013). Watercolour paper, recycled paper, origami paper and transparency paper are just some of the types of paper that differ considerably from each other. In kindergarten, simple papermaking techniques are more prevalent at first, which helps us develop related skills such as creasing, tearing, folding and creasing. Later, we develop cutting, gluing and even punching, hole-punching and stapling.Cutting, gluing, punching and stapling require tools, while the other techniques are carried out without tools. In kindergarten, children's scissors, pattern scissors, hole punch, stapler and various rulers or stencils are most commonly used (Milčinovič, 1997). Children's scissors vary in size, shape of handle, colour, length and shape of blades (they have a rounded blade). They can be right-handed or left-handed, and some have a scissor opening aid to make them easier to use. Rulers are less frequently used by children in kindergarten. Beside classic ruler, we also know triangular rulers and curved rulers for drawing curved lines. If rulers have blank spaces on the base for drawing different shapes and figures, they are called stencils. When drawing lines with a ruler, it is important to hold the tip of the pencil right against the side of the ruler. This should be inclined in the direction where the line is drawn (Fošnarič, Slukan, Virtič, Puncer 2004). Using a hole punch helps us to cut an opening in paper materials. There are punches that use a hammer to punch a hole in a hard substrate and those that are automatic (ibid.). The choice of stapler depends on the number of sheets of paper to be stapled at one time. Desktop office staplers can staple from 2 to 50 sheets. Manual staplers or staplers can also staple from 2 to 40 sheets. Electric staplers can staple more sheets. Paper clip remover are used to remove staples from stapled material.

Verdigris sodi med najpomembnejše in pogosto uporabljene pigmente zelene oziroma modrozelene barve od antike do 19. stoletja. Njegova barva se spreminja s časom in v odvisnosti od atmosferskih pogojev. Kljub slabi obstojnosti je bil med umetniki zelo priljubljen. Ker je semitransparenten in ne prekriva tiskarskega črnila, ga najdemo na iluminacijah, ilustracijah knjig in zemljevidih. Poznamo dve vrsti verdigrisa, in sicer nevtralni in bazični verdigris. Verdigris ne spreminja zgolj svoje barve, ampak povzroča tudi razgradnjo nosilca, na katerega je nanesen. Ker so ogrožena tudi številna zgodovinska umetniška dela, so študije stabilizacije pigmenta in razvoj konservatorsko-restavratorskih postopkov izjemnega pomena. V magistrskem delu sem raziskovala razgradnjo in možnosti za stabilizacijo različnih modelnih papirjev z nanesenim pigmentom verdigris. Študirala sem tri različne modelne papirje, in sicer Whatman No. 1 filtrirni papir kot referenčni papir in dva različna ročno izdelana papirja, ki sta podobna zgodovinskim papirjem. Vzorce papirja s pigmentom verdigris sem izpostavila pogojem termično pospešene razgradnje pri 50 °C in 65 % relativne vlažnosti, ki poteka primerljivo z razgradnjo pri sobnih pogojih. Za študije stabilizacije papirja sem uporabila dva antioksidanta, ki sta se do sedaj izkazala za najbolj učinkovita, in sicer 1(H)-benzotriazol (BTA) in tetrabutilamonijev bromid (TBABr). Z atomsko absorpcijsko spektroskopijo sem določila vsebnost bakra v modelnih vzorcih papirja in ugotovila, da lahko z uporabo ročne pršilke pripravimo vzorce z enakomernim nanosom pigmenta na papir. S spremljanjem pH vrednosti vzorcev papirja sem ugotovila, da do pretvorbe nevtralnega v bazični verdigris pride v prvem mesecu termično pospešene razgradnje. pH vrednosti papirja so pokazale, da za stabilizacijo papirja zadostuje zgolj uporaba ustreznega antioksidanta, brez dodatka alkalije oziroma sredstva za razkislinjenje. Tudi meritve spremembe barve vzorcev papirja nakazujejo na dejstvo, da se nevtralni verdigris sčasoma pretvarja v različne zelene oblike bazičnega verdigrisa. Izmed obeh antioksidantov je z vidika barvne obstojnosti takoj po nanosu najbolj učinkovit TBABr, saj so bile spremembe barve minimalne, vendar so bile po treh mesecih termično pospešene razgradnje bolj izrazite kot pri vzorcih, obdelanih z BTA. Poleg tega so na nekaterih vzorcih nastale črne pike, kar ni zaželeno. S spremljanjem stopnje polimerizacije (DP) celuloze sem ugotovila, da je najbolj učinkovit antioksidant za stabilizacijo TBABr, saj je bila razgradnja papirja, obdelanega s TBABr, po treh mesecih termično pospešene razgradnje v povprečju manjša za 33 % v primerjavi z neobdelanimi papirji. V nasprotju pa BTA ni izkazal pozitivnih učinkov na stabilizacijo papirja. Primerjava DP vrednosti, določenih z velikostno izključitveno kromatografijo in z viskozimetrijo, kaže, da bi lahko bila viskozimetrija primerna za določanje DP vrednosti za papir z verdigrisom. Meritve mehanskih lastnosti so pokazale, da pri neobdelanih vzorcih papirja po treh mesecih termično pospešene razgradnje ni prišlo do tako izrazite izgube mehanskih lastnosti, kot bi lahko pričakovali glede na določene vrednosti stopnje polimerizacije celuloze. Z ramansko spektroskopijo smo potrdili, da smo za pripravo barve uporabili nevtralni verdigris, ki se s časom spreminja v različne oblike bazičnega verdigrisa, ne glede na to, ali je papir obdelan z antioksidantom ali ne. Za stabilizacijo papirja z nanesenim pigmentom verdigris je na osnovi rezultatov najbolj primeren antioksidant TBABr, saj je bil pri zaviranju razgradnje papirja najbolj učinkovit. Poleg tega ni imel negativnega vpliva na pH vrednost papirja in ni povzročil izrazitih sprememb barve takoj po nanosu. Negativni učinek se je pokazal zgolj po treh mesecih termično pospešene razgradnje, saj so na nekaterih vzorcih pojavile črne pike. Vzrok za to je potrebno pred uporabo postopka na originalnih dokumentih natančno raziskati. Verdigris is one of the most important and frequently used green or blue-green pigments from antiquity until the 19th century. Its colour changes with time and depending on atmospheric conditions. Despite its poor durability, it was extremely popular among artists. Because it is semi-transparent and does not obscure the printed ink, it can be found on illuminations, book illustrations and maps. There are two types of Verdigris, namely neutral and basic Verdigris. Verdigris does not only change its colour, but also causes the degradation of the substrate on which it is applied. Since many historical works of art are also at risk, studies of pigment stabilization and the development of conservation-restoration procedures are of utmost importance. In my master’s thesis I investigated the degradation and possibilities for stabilization of various model papers with applied pigment Verdigris. I studied three different model papers, namely Whatman No. 1 filter paper as a reference paper and two different handmade papers that resemble historical papers. Paper samples with pigment Verdigris were exposed to conditions of thermal accelerated degradation at 50 °C and 65 % relative humidity, which are comparable to the degradation of paper with pigment Verdigris at ambient conditions. For paper stabilization studies, two antioxidants that have proven to be the most effective so far, 1(H)-benzotriazole (BTA) and tetrabutylammonium bromide (TBABr), were used. The copper content in model paper samples was determined using atomic absorption spectroscopy. The results show that an even application of the pigment on paper samples can be obtained using a spray gun. Monitoring the pH value of paper samples showed that the alteration of neutral to basic Verdigris occurs in the first month of thermal accelerated degradation. The pH values of paper indicate that for the stabilization of paper the use of an appropriate antioxidant, without the addition of alkali or deacidification agent, is sufficient. Measurements of the colour change of paper samples also indicate the fact that the neutral Verdigris eventually transforms into various forms of basic Verdigris. From the point of view of colour persistence immediately after application, TBABr is the most effective of the two antioxidants, as colour changes were minimal, but after three months of thermal accelerated degradation, the degradation was more pronounced than in samples treated with BTA. In addition, black spots appeared on some samples, which is not desirable. By monitoring the degree of polymerisation (DP) of cellulose, I found that the most suitable antioxidant for inhibiting cellulose degradation is TBABr, as the degradation of paper treated with TBABr was on average 33 % lower after three months of thermal accelerated degradation compared to untreated papers. In contrast, BTA did not show significant stabilization. Comparison of DP values, determined by size exclusion chromatography and by viscometry, indicates that viscometry may be suitable for determining DP values for Verdigris paper. Measurements of the mechanical properties showed that the untreated paper samples did not show as pronounced loss of mechanical properties after three months of thermal accelerated degradation as might be inferred from the determined values of the degree of polymerisation of cellulose. Using Raman spectroscopy, we confirmed that neutral Verdigris was used to prepare the colour, which changes over time into different forms of basic Verdigris, regardless of whether the paper is treated with an antioxidant or not. Based on the obtained results, the antioxidant TBABr is the most suitable for stabilizing paper with applied pigment Verdigris, as it was the most effective in inhibiting paper degradation. In addition, it had no negative effect on the pH value of paper and did not cause significant colour changes immediately after application. The negative effect became apparent only after three months of thermal accelerated degradation, as black dots appeared on some samples. The cause of the appearance of these black dots must be carefully studied before the treatment is used on original documents.

Doktorsko delo temelji na treh znanstvenih člankih s področja razvoja trajnostnih polimernih embalažnih materialov. V sklopu raziskav za pripravo omenjenih člankov so bili z uporabo večinoma lokalno dostopnih surovinskih virov razviti novi, različni, trajnostni, polimerni embalažni materiali, ki bodo v prihodnje lahko služili kot alternativa običajnim, osnovanim iz naftnih derivatov. Prav tako so bili pripravljeni premazi iz obnovljivih virov, ki služijo predvsem za izboljšanje bariernih lastnosti papirjev ter bodo v prihodnje lahko predstavljali nadomestek nekaterim sintetičnim premazom. V prvi fazi raziskav je bil s postopkom elektropredenja iz mulja, ki nastaja pri čiščenju odpadnih komunalnih vod, pridobljen nov, gibek, tanek material, potencialno uporaben za embalažne namene. Mulj je bil pred postopkom elektropredenja očiščen z uporabo etilendiamintetraocetne kisline. Sestavo in čistost mulja smo določali z uporabo infrardeče spektroskopije s Fourierjevo transformacijo, bližnje infrardeče spektroskopije in termogravimetričnih analiz. Za najnatančnejše analize, smo se posluževali jedrske magnetne resonance. Z nateznim testom smo analizirali mehanske lastnosti novo razvitega materiala, z uporabo elektronskega vrstičnega mikroskopa pa njegovo homogenost in morfološke značilnosti. V drugi fazi raziskave so bili s postopkom vlivanja izdelani tanki, gibki filmi, katerih glavne komponente so bile: bakterijska nanoceluloza (pridobljena iz alternativnega surovinskega vira – kisove matice), nanokristalinična in nanofibrilirana celuloza, alginat ter hitozan. Vse komponente filmov so bile pred vlivanjem okarakterizirane z uporabo različnih analitičnih tehnik. Novo razvite filme smo okarakterizirali predvsem z vidika fizikalno–mehanskih lastnosti (natezne lastnosti) in bariernih lastnosti (prepustnost za vodno paro in kisik), pri čemer smo določili vpliv sestave na omenjene lastnosti. V zadnjem delu raziskav smo preučevali vpliv različnih premazov na barierne lastnosti komercialno dobavljivega, industrijsko izdelanega papirja. Sprva smo pripravili premazne mešanice, osnovane na škrobu, z dodanimi različnimi deleži ligninov iz različnih surovinskih virov. Premazne mešanice smo nato nanesli na površino izbranega papirja. Z meritvami prepustnosti vodne pare, odpornosti na maščobe, olja itd. premazanih papirjev smo določili vpliv bio-osnovanih premazov na barierne lastnosti, prav tako smo določili tudi mehanske in fizikalne lastnosti papirja. The PhD thesis is based on three scientific papers from the field of development of sustainable polymer packaging materials. The research for these papers has resulted in new, different, sustainable, polymeric packaging materials, using mostly locally available raw material sources, which could serve as an alternative to conventional petroleum-based materials in the future. Coatings from renewable sources have also been developed, which serve mainly to improve the barrier properties of papers and may in the future provide a substitute for some synthetic coatings. In the first phase of the research, a new, flexible, thin material, potentially useful for packaging purposes, was obtained by electrospinning from sludge produced during the treatment of municipal wastewater. The sludge was cleaned using ethylenediaminetetraacetic acid prior to the electrospinning process. The composition and purity of the sludge were determined using Fourier transform infrared spectroscopy, near-infrared spectroscopy, and thermogravimetric analyses. For the most accurate analyses, nuclear magnetic resonance was used. The mechanical properties of the newly developed material were analysed by tensile tests and its homogeneity and morphological characteristics were analysed by electron line microscopy. In the second phase of the research, thin, flexible films were produced by a casting process, the main components of which were: bacterial nanocellulose (obtained from an alternative raw material source - vinegar nut), nanocrystalline and nanofibrillated cellulose, alginate, and chitosan. All film components were characterised prior to casting using different analytical techniques. The newly developed films were characterised mainly in terms of mechanical-physical properties (tensile properties) and barrier properties (water vapour and oxygen permeability), and the influence of composition on these properties will be determined. In the last part of the research, the influence of different coatings on the barrier properties of commercially available, industrially produced paper was investigated. Initially, starch-based coating blends were prepared with different proportions of lignins from different raw material sources added. The coating blends were then applied to the selected paper. By measuring the water vapour permeability, fat, and oil resistance, etc. of the coated papers, the influence of the bio-based coatings on the barrier properties was determined, as well as the mechanical and physical properties of the paper.

V diplomskem delu obravnavam tri risbe v tehniki kreda na papirju, ki so umetniška dela slikarja Franca Košarja. Risbe so v lasti Pomurskega muzeja Murske Sobote in so bile dane v konservatorsko-restavratorsko obdelavo v Center za konserviranje in restavriranje v Arhivu Republike Slovenije. Po kratki predstavitvi avtorja in risarskih tehnik na papirju sledi opis konservatorsko-restavratorskih posegov, ki so potekali v sodelovanju z Arhivom Republike Slovenije. Praktični del sestavlja opis stanja risb, konservatorsko-restavratorski načrt za posege ter predstavitev izvedbe konservatorsko-restavratorskih posegov, predvsem na risbi Akt moškega s palico v levici. Sledi predlog za primeren način okvirjanja risb, ki ga bodo izvedli v Pomurskem muzeju Murska Sobota ter priporočila o ustreznih mikroklimatskih pogojih za razstavljanje in shranjevanje umetnin. In my thesis, I discuss three drawings in chalk technique on paper, which are works of art created by the painter Franc Košar. The drawings are owned by Pomurski muzej Murska Sobota and were given to the Center za konserviranje in restavriranje in the Arhiv Republike Slovenije to undergo conservation and restoration work. Firstly I will briefly present the author and his work, followed by a presentation of drawing techniques and paper, a description of the conservation-restoration of the drawing Akt moškega s palico v levici (Nude of man with a stick in his left hand) that took place in collaboration with the Archives of the Republic of Slovenia. Finally, I decribe a proposal for a suitable framing method for the drawings which will be carried out in the Pomurski muzej Murska Sobota, as well as recommendations on suitable microclimate conditions for displaying and storing works of art.

Aglomeracija delcev v premazni mešanici se izkazuje kot nezaželen učinek in ima negativen vpliv na končni izdelek premazanega papirja. Vsak osnovni papir, ki pride iz papirnega stroja, ima naravno reliefno strukturo površine, ki je neenakomerna in groba. Če mu želimo izboljšati površinske lastnosti, mu je na površino treba dodati premaz. Papir ali karton premazujemo z različnimi premaznimi mešanicami. Slednje so sestavljene iz pigmentov, veziv, koveziv, pomožnih sredstev in vode. V premaznih mešanicah se delci med seboj povezujejo v večje skupke oz. aglomerate. Aglomeracija kalcijevega karbonata kot pigmenta je negativni pojav vseh disperznih sistemov, ki se mu ni moč izogniti in predstavlja neposredni rezultat medsebojnega učinkovanja dispegiranih delcev in tekočine, kar vpliva na mikrostrukturo papirja. Zaradi neenakomernega tvorjenja aglomeratov po površini je ta na mikro ravni še vedno nekoliko hrapava, hrapavost pa je učinek, katerega vpliv si želimo s premazovanjem zmanjšati in poskusiti površino narediti bolj gladko. Smisel premazovanja papirja je tvorjenje bolj enakomerne površine, s čimer se izboljša potiskljivost oz. tiskovne lastnosti. Slednje vpliva predvsem na izboljšanje površinskih in optičnih lastnosti, kot so gladkost, sijaj, belina, neprosojnost, enakomernost površine, kakovost tiska, enakomerno navzemanje tiskarske barve in sposobnost lakiranja. Namen magistrskega dela je bil preučiti vpliv različnih sestav receptur premaznih mešanic in kako le-te vplivajo na stopnjo aglomeracije kalcijevega karbonata, kakšna je vloga veziv, katera komponenta v največji meri prispeva k zniževanju oz. zviševanju stopnje aglomeracije ter ugotoviti, kako ustrezna je v raziskavo zajeta fizikalno-mehanska metoda zmanjševanja stopnje aglomeracije s pomočjo ultrazvoka. Z raziskavo smo preučevali lastnosti premazanih papirjev, tj. osnovne, površinske, strukturne in optične lastnosti, in s slikovno analizo preko elektronskega vrstičnega mikroskopa (SEM) pridobili podrobnejši vpogled v mikro dogajanje sestavnih delov premaznih mešanic, ki jih v svojem proizvodnem procesu uporablja Papirnica Vevče. Preučevanih je bilo 6 različnih vzorcev, z različno vsebovanostjo kalcijevega karbonata in kaolina. Vzorce smo v nadaljevanju razdelili v 3 sklope, tj. glede na namen obdelave. To so bili vzorci premazanih mešanic, vzorci premaznih mešanic, ki so bili obdelani z ultrazvokom 5 min pri temperaturi 35 °C in vzorce obdelane z ultrazvokom 5 min pri temperaturi 45 °C. Rezultati so pokazali, da je bila aglomeracija višja pri vzorcih, ki so vsebovali večji delež CaCO3 glede na sklop vzorcev z večjim deležem kaolina. Kalcijev karbonat dosega najvišje vrednosti hrapavosti, poroznosti, togosti in zrcalnega sijaja. K večji aglomeraciji so delno pripomogla tudi veziva in sprememba temperature. Fizikalno-mehansko obdelovanje z ultrazvokom ne more v zadostni meri premagati kemijskega privlaka med pigmentnimi delci, kar rezultira v delni aglomeraciji. Večji aglomerati so se sicer razbili na manjše, zmanjšala se je tudi velikost pigmentnih delcev CaCO3 in kaolina, vendar ultrazvok ni izničil pojava aglomeracije. Agglomeration of particles in the coating mixture is an undesirable effect and has a negative impact on the final coated paper product. Each base paper coming out of the paper machine has a natural embossed structure which is uneven and rough. If we want to improve its surface characteristics, it is necessary to add a coating to the surface of the paper. Paper or cardboard is coated with different coating mixtures. These consist pigments, binders, metal binders, auxiliaries and water. In coating mixtures, the particles are connected together to form larger aggregates or agglomerates. Agglomeration of calcium carbonate as a pigment is an unavoidable negative process of all dispersions and is a direct result of the interaction between the dispersed particles and the liquid, which affects the microstructure of the paper. The uneven formation of agglomerates on the surface still results in a slightly rough surface on micro level, and roughness is an effect whose impact we want to reduce by coating the paper and try to make the surface smoother. The purpose of coating the paper and making the surface as even as possible is to improve its printability or its printability characteristics. This mainly affects on the improvement of surface and optical properties such as smoothness, gloss, whiteness, opacity, surface uniformity, print quality, uniform ink uptake and the abičity to varnish. The aim of the MSc thesis was to study how different coating formulations affect on the level of agglomeration of calcium carbonate, what is the role of binders, which component contributes the most to reducing or increasing the level of agglomeration, and to determine how suitable is the physico-mechanical method of reducing the level of agglomeration by ultrasonication. Trough research we studied the properties of the coated papers (basic, surface, structural and optical properties) and trough image analysis using a scanning electron microscope (SEM), obtained a more detailed insight into the micro-evolution of the components of the coating mixtures used by Papirnica Vevče in its production process. Six different samples with different contents of calcium carbonate and kaolin were studied. The samples were further divided into 3 sets according to the purpose of the treatment. These were samples of coated mixtures, samples of coated mixtures treated by ultrasonication for 5 min at 35 °C and samples treated by ultrasonication for 5 min at 45 °C. The results showed that agglomeration was higher in samples containing a higher proportion of CaCO3 compared to the set of samples with a higher proportion of kaolin. Calcium carbonate has the highest values of roughness, porosity, stiffness and gloss. The higher agglomeration is partly due to the binder and the change in temperature. Physico-mechanical treatment with ultrasound cannot sufficiently overcome the chemical attraction between the pigment particles, resulting in partial agglomeration. Although the larger agglomerates were broken down into smaller ones and the size of the pigment particles CaCO3 and kaolin was reduced, ultrasound did not cancel the agglomeration process.

V tem magistrskem diplomskem delu sem primerjal in ugotovil, da sta si postopka začetnih javnih ponudb delnic in kriptoimetij v marsičem podobna. Začetna javna ponudba delnic ni več rezervirana le za uveljavljene in uspešne družbe, kot tudi začetnih javnih ponudb kriptoimetij ne izvajajo le mlada, zagonska podjetja. Nadalje sem opazil, da sta si prospekt in bela knjiga v marsičem podobna, pri čemer so informacije glede bele knjige v določenih segmentih celo bolj zahtevne. Delnice in kriptoimetja nenazadnje ustvarjajo različne učinke pri lastništvu v podjetju, računovodskem vrednotenju in prikazovanju v finančnih izkazih ter ob prenehanju podjetja. EU si prizadeva ustvariti kapitalsko unijo, a menim, da ta ni bila izvedena do konca, saj države članice nimajo enotne interpretacije finančnih instrumentov. Posledično, ker nekatera kriptoimetja posnemajo lastnosti finančnih instrumentov, navedeno povzroča različne pristope držav članic pri obravnavi kriptoimetij. Ker resnične unije in enotnosti trga ni, Uredba MiCA ne bo mogla odpravila že ustvarjenih neučinkovitosti. Zato se postavljajo vprašanja, kako nasloviti in zapolniti zadevne sive cone v pristopih držav članic, da ne bo odvrnilo podjetij od izvedbe začetne javne ponudbe kriptoimetij in ustvarjanjem inovacij znotraj trga EU. Menim, da je EU hitela z regulacijo področja kriptoimetij zaradi strahu pred negativnim vplivom kriptoimetij na učinkovito vodenje monetarne politike, stabilnostjo (fiat) valut in tudi vzpostavitvijo vzporedne virtualne ekonomije. Določena kriptoimetja lahko istočasno namreč opravljajo tako funkcijo virtualne valute kot investicije. Na drugi strani pa delnice kvečjemu lahko opravljajo funkcijo investicije, niso pa dojete kot oblika katerekoli valute. In this Master's thesis, I have compared and found that the processes of initial public offerings and initial coin offerings are similar in many aspects. Initial public offerings are no longer reserved for established and successful companies, nor are initial coin offerings only carried out by start-up companies. Furthermore, I have noticed that the prospectus and the white paper are similar in many aspects, with the white paper information being even more complex in certain segments. Shares and cryptocurrencies create different effects in terms of ownership in the company, accounting valuation and presentation in the financial statements, and on winding-up. The EU is working to create a capital markets union, but I believe that it has not been fully implemented because the Member States do not have a uniform interpretation of financial instruments. As a result, since some crypto-assets mimic the characteristics of financial instruments, this leads to different approaches by Member States in dealing with crypto-assets. In the absence of a true union and market unity, the MiCA Regulation will not be able to address the inefficiencies already created. This raises questions as to how to address and fill the relevant grey areas in Member States' approaches so as not to discourage firms from conducting initial coin offerings and creating innovation within the EU market. I believe that the EU has rushed to regulate crypto-assets due to the fear of the negative impact of cryptocurrencies on the effective conduct of monetary policy, the stability of (fiat) currencies, and also the creation of a parallel virtual economy. Certain cryptocurrencies can act as virtual currencies and investments at the same time. Shares, on the other hand, can at most perform the function of an investment but are not perceived as a form of any currency.

Delo obravnava regeneracijo odpadne toplote sušilnega zraka, ki se odvaja iz papirnega stroja pri sušenju papirja. Predstavljena je osnovna zasnova in delovanje papirnega stroja z njegovimi sestavnimi deli. V uvodnem delu so predstavljeni tudi prenosniki toplote, ter osnovna teorija njihovega preračunavanja. Podrobneje je obravnavana teorija cevnih prenosnikov toplote s križnim tokom, ker se tovrstni prenosniki uporabljajo v papirnicah za regeneracijo toplote. Izveden je matematični model preračuna cevnega prenosnika toplote s križnim tokom. V nadaljevanju je s tem modelom izveden izračun prenosnika za realni papirni stroj. Določene so dimenzije prenosnika, temperature na vstopu in izstopu, ter učinkovitost prenosnika. V zaključnem delu je izvedena primerjava rezultatov izračunanih z namenskim licenčnim programskim paketom. This assignment examines the regeneration of waste heat from drying air which is discharged from paper machine during the process of paper drying. It also includes an explanation of the basic layout and operation of the paper machine and its components. In addition to the latter, the introduction includes the presentation of the heat exchangers and the general theory of their calculations. A theory of tubular heat exchangers with cross flow is additionally closely examined, that is because those exchangers are used in paper mills for heat regeneration. A mathematical calculation model of tubular heat exchangers with cross flow is performed. With the use of previously mentioned model, calculations for exchanger in the real paper mill were made. Certain specifications were given, such as exchanger’s dimensions, temperatures at the input and the output, and exchanger’s efficiency. In the concluding part of this assignment, a comparison of calculated results is presented with dedicated licensed software packages.

V magistrski nalogi smo ugotavljali vpliv dekorativnega sloja na emisijo formaldehida iz ivernih plošč. Namen je bil predvsem ugotoviti kakšen je zaviralni učinek oziroma ovira posameznih dekorativnih sistemov, ki se običajno uporabljajo v proizvodnji pohištva. Za analizo emisije formaldehida je bila uporabljena eksikator metoda (ISO 12460-4:2008). Ugotovljeno je bilo, da je večina dekorativnih sistemov imela manjšo emisijo formaldehida od referenčne, kar pomeni, da je večina le teh bila učinkovita pri zaviranju emitiranja formaldehida. Največje emisije formaldehida sta imela impregnirana papirja v primerjavi z referenčnimi ploščami. Še vedno pa so imeli manjšo koncentracijo formaldehida v primerjavi s ploščami, ki so imeli vse površine odprte. HPL 2 in en sloj Belinke imata zelo podobni emisiji formaldehida, in sicer HPL 2 ima 0,0387 mg/L, medtem ko en sloj Belinka ima 0,0383 mg/L. Najmanjšo emisijo formaldehida, kar pomeni najbolj učinkovit zaviralec emitiranja, predstavlja interier Belinka z dvema nanosoma. Lahko rečemo, da so načeloma vsi dekorativni materiali imeli nek zaviralni učinek emitiranja formaldehida. In the master's thesis, we determined the influence of a decorative layer on the emission of formaldehyde from particleboards. The main purpose was to find out what is the inhibitory effect or obstacle of individual decorative systems that are usually used in the production of furniture. The desiccator method (ISO 12460-4:2008) was used to analyze the formaldehyde emission. It was found that most of the decorative systems had a lower formaldehyde emission than the reference boards, which means that most of them were effective in suppressing the emission of formaldehyde. Impregnated papers had the highest formaldehyde emissions compared to the reference panels. However, they still had a lower concentration of formaldehyde compared to panels that had all surfaces open. HPL 2 and one layer of Belinka have very similar formaldehyde emissions, namely HPL 2 has 0,0387 mg/L, while one layer of Belinka has 0,0383 mg/L. The lowest formaldehyde emissions, which means the most effective emission inhibitor, was found for the interior of Belinka with two layers. It can be said that, in principle, all decorative materials had some inhibitory effect on the emissions of formaldehyde.

Diplomsko delo obravnava oblikovanje in izdelavo embalaže za klekljan nakit ter vizitke, ki se povezujejo z embalažo. Cilj diplomskega dela je, da bi se za klekljan nakit izdelala posebna vrsta embalaže, ki se po navadi ne uporablja pri embaliranju nakita ter da embalaža ni za enkratno uporabo, temveč se jo lahko ponovno uporabi. Posebnost embalaže je tudi vrsta materiala, iz katerega je izdelana, saj gre za papirje in kartone izdelane iz invazivnih rastlin. Teoretični del predstavlja osnove embalaže, pomen in uporabo darilne embalaže ter pregled trga že obstoječih in uporabljenih embalaž za klekljane izdelke. V eksperimentalnem delu je opisano preizkušanje petih različnih vrst papirja, ki so jih izdelali na Inštitutu za celulozo in papir. Uporabili smo papir iz Miskantusa, dva vzorca papirja različne gramature iz Navadne robinije – »akacije« ter dva vzorca papirja različne gramature iz japonskega dresnika. Določene so bile osnovne, mehanske, površinske, strukturne in optične lastnosti papirjev. Na podlagi opravljenih meritev smo za izdelavo embalaže in vizitke izbrali visokogramska papirja iz Navadne robinije in Japonskega dresnika, saj oba vzorca izkazujeta primerno visoko razpočno in raztržno odpornost. Sama oblika embalaže za nakit je posebna, spominja na romantično kuverto. Dodan vzorec metulja nas obdaja z občutkom nežnosti ter doda 3D efekt. Kot ilustracijo, napis in logotip smo uporabljali osnovne elemente ter uporabljali samo črno barvo pri tisku. The thesis deals with the design and production of new packaging for a piece of bobbin lace jewellery and business cards, which is associated with the packaging. The goal of the thesis is to create a type of packaging for the bobbin lace jewellery, which is usualy not used in jewellery packaging, and to make the packaging reusable. The packaging is also special because of the type of material from which is made, as it is paper and paperboard produced from invasive plants. The theoretical part presents basic data about packaging, the meaning and the use of gift packaging, as well as an overview of the existing packaging for the bobbin lace products in the market. The experimental part describes the testing of five different types of paper produced at Pulp and Paper Institute in Ljubljana. Paper from Miscanthus, two samples of Robinia (black locust) paper of different grammage, and two samples of Japanese knotweed paper of different grammage were used. The basic, mechanical, surface, structural and optical properties were determined. Based on the measurements, we used high-grammage paper from Robinia and Japanese knotweed for the production of packaging and business cards, as both samples show a correspondingly high burst and tear resistance. The shape of the jewellery box itself is very special, reminiscent of a romantic envelope, and the added butterfly pattern surrounds us with a feeling of tenderness and adds a 3D effect. We used the basic elements as illustration, lettering and logo, and only used black for printing.

Namen magistrske naloge je bil ugotoviti, kakšen vpliv imajo temperaturne spremembe in čas izpostavljenosti temperaturnim spremembam na mehansko obstojnost odtisov in belino, ter barvni odtenek beline papirja. Preučevani so bili odtisi, natisnjeni na dve vrsti papirja (mat in sijajni premaz) s kapljičnim tiskalnikom. Raziskava je obsegala oblikovanje merske tablice, na kateri je bilo osem barvnih polj s štirimi barvami (CMYK). Vsaka barva je bila prikazana s 100% in 50% pokritostjo. Odtisi so bili izpostavljeni različnim temperaturnim spremembam (-12 °C, 6 °C, sobna temperatura, izmenična temperatura med sobno in 6 °C) za tri časovna obdobja. Časovni intervali so bili dolgi po šest dni (6, 12 in 18 dni). Po vsakem intervalu je bila preverjena obstojnost vzorcev na drgnjenje, belino papirja in barvni odtenek beline papirja. Barvne razlike so bile izračunane iz izmerjenih spektrofotometričnih vrednosti na vzorcih. Ugotovljeno je bilo, da vrsta papirja in njegovega premaza vpliva na končno mehansko obstojnost odtisov, ki so bili izpostavljeni temperaturnim spremembam. V splošnem je imel papir 2 (mat premaz) veliko bolj konsistentne rezultate in vzorci tega papirja kažejo večinoma boljšo obstojnost na drgnjenje, kot tisti na papirju 1 (sijajni premaz). Iz rezultatov je razvidno, da je izpostavljenost temperaturnim spremembam vplivala na obstojnost odtisov na drgnjenje. Na papirju, ki je bil premazan z sijajnim premazom (papir 1), so bile zaznane večje barvne razlike v primerjavi z mat premazom (papir 2). V povprečju so imeli odtisi na papirju 1 največje barvne razlike po 12 dneh in odtisi na papirju 2 po šestih dneh izpostavljenosti temperaturnim spremembam. Belina papirja in barvni odtenek beline sta se po določenem času izpostavljenosti le minimalno spremenila in sprememb zelo verjetno ne bi mogli zaznati s prostim očesom. The main aim of the study was to determine the effect of temperature changes and its time of exposure on the mechanical stability of prints, paper whiteness, and tint of whiteness. Imprints were printed with inkjet printer on two types of coated paper (matt and glossy). The research included the design of pattern, which was printed. It included eight color fields with four colors (CMYK). Each color was displayed with 100% and 50% coverage. Imprints were exposed to different temperatures (-12 °C, 6 °C, room temperature, alternating temperature between room temperature and 6 °C) for three time periods. The time intervals were six days long (6, 12, and 18 days). After each interval, we checked the abrasion stability of the samples, whiteness of the paper, and the tint of whiteness. Color differences were calculated from the measured spectrophotometric values of the samples. The results showed that the type of paper and its coating affects the final mechanical stability of prints that were exposed to temperature changes. In general, paper 2 (matt coating) has much more consistent results and prints of this paper mostly show better abrasion resistance than those on paper 1 (glossy coating). The results show that exposure to temperature changes affects the mechanical stability of prints. Larger color differences were detected on glossy coated paper (paper 1) compared to matt coating (paper 2). On average, prints on paper 1 had the largest color differences after 12 days of exposure and prints on paper 2 after six days of exposure to temperature changes. The whiteness of the paper and the tint of whiteness had minimal changes with exposure time that cannot be detected with the naked eye.

Papirna industrija je ena izmed večjih onesnaževalk okolja. Inovacije in tehnološki napredek sta prinesla izboljšave na področju varovanja okolja in zapiranja snovno energetskih tokov. V magistrski nalogi smo primerjali scenarije razčrniljenja z uporabo kemikalij (tradicionalen način), komercialnih encimov (dostopnih na trgu), ter lastnih encimov. Lastne encime pridobivamo z kultivacijo glive Pleurotus ostreatus na gojišču iz papirniškega mulja, odpadka pri proizvodnji papirja. Z večkriterijskem odločanjem z metodo DEX smo ovrednotili tri scenarije razčrniljenja papirja. Kriteriji ocenjevanja so se nanašali na kazalnike ekonomske uspešnosti, družbenih učinkov, okoljske trajnosti in krožne naravnanosti. Primerjalne ocene scenarijev smo pridobili od strokovnjakov s področja papirništva v dveh krogih (individualno anketiranje in skupinsko usklajevanje po metodi Delphi). Za scenarij razčrniljenja papirja z lastnimi encimi smo izvedli še bolj podrobno analizo z uporabo troslojnega kanvas poslovnega modela (TKPM), kjer smo opazovali in opisali ekonomski, okoljski in družbeni vpliv take proizvodnje papirja. Rezultati raziskave kot najugodnejšega z vidika skupne trajnosti izpostavljajo scenarij razčrniljenja papirja z lastnimi encimi. Sledi mu scenarij razčrniljenja s komercialnimi encimi, kot najslabši pa se iz vidika skupne trajnosti izkazuje scenarij razčrniljenja s kemikalijami. The paper industry is one of the biggest polluters of the environment. Innovation and technological progress brought improvements in terms of environmental protection and closing material and energy loops. This master thesis focused on the deinking process, which is part of the paper manufacturing process. We compared different scenarios using chemicals (traditional approach), commercial enzymes, and proprietary enzymes. Proprietary enzymes are produced using the fungus Pleurotus ostreatus on a medium of paper sludge. The DEX method was used for a multi-criteria evaluation of the three scenarios of the deinking process. The evaluation criteria were related to indicators of economic performance, social impact, environmental sustainability, and circular economy. The comparative assessment of the scenarios was conducted in two rounds (following Delphi principles). For deinking with proprietary enzymes, we performed an even more detailed analysis using a three-layered canvas business model (TCBM), where we observed and described the economic, environmental, and social impacts of such paper production. The results of the analysis show that the scenario of deinking with proprietary enzymes is the most favourable in terms of overall sustainability. This is followed by the scenario with commercial enzymes. The worst scenario in terms of overall sustainability is deinking with chemicals.

V papirni industriji se porablja in onesnažuje velika količina vode. S pomočjo bioaugmentacije bi lahko zmanjšali količino neželenih prisotnih snovi v tehnološki vodi in tako zmanjšali porabo vode. V okviru magistrskega dela smo izbrali najboljšo kombinacijo bakterij, ki razgrajuje snovi prisotne v tehnološki vodi tovarn brezlesnega papirja in ima zato velik potencial za uporabo v biološkem čiščenju. Posamezne bakterije izolirane iz tehnološke vode tovarn brezlesnega papirja smo najprej identificirali in testirali njihovo sposobnost razgradnje snovi, ki so prisotne v tehnološki vodi tovarn brezlesnega papirja. Testirali smo njihovo sposobnost razgradnje azo barvil, fluorescentnega barvila, škroba, celuloze, emulzije lateksa in alkil keten dimerov. Nato smo sestavili smiselne kombinacije najaktivnejših sevov in jih testirali v modelni tehnološki vodi. Analizirali smo prisotnost inokuliranih bakterij v kombinacijah po izpostavitvi v modelni tehnološki vodi, da bi ugotovili negativne in pozitivne interakcije med posameznimi sevi. Odločili smo se za kombinacijo sevov Xanthomonas sp., Cellulosimicrobium sp. Aeromonas sp., Klebsiella sp. in Agromyces sp.. The paper industry consumes and pollutes a large amount of water. With the help of bioaugmentation, the amount of unwanted substances present in the white water could be reduced and thus water consumption would be reduced. The main emphasis of this master degree thesis is to choose the best combination of bacteria that degrades the substances present in the white water of the wood-free paper mills and therefore has great potential for use in biological treatment. Individual bacteria isolated from the white water of wood-free paper mills were first identified and tested for their ability to degrade the substances that are present in the white water of wood-free paper mills. Their ability to degrade azo dyes, fluorescent dye, starch, cellulose, latex emulsion, and alkyl keten dimers was tested. Then meaningful combinations of most active strains were assembled and tested in synthetic white water. The presence of inoculated bacteria in combination after exposure in synthetic white water was analyzed to determine the negative and positive interactions between individual strains. A combination of strains Xanthomonas sp., Cellulosimicrobium sp., Aeromonas sp., Klebsiella sp. and Agromyces sp. was choosen.

Magistrsko delo se navezuje na dve raziskovalni področji, in sicer 3D-računalniško grafiko in obogateno resničnost s kombinacijo njunega prikazovanja na mobilnih napravah. Naloga predstavlja izdelavo treh različnih interaktivnih 3D-modelov, ki temeljijo na realistično risani podobi domačih živali in jih je mogoče prikazati s pomočjo obogatene resničnosti na mobilnih napravah. Živali se prikazujejo v izdelani aplikaciji Obogatene živali z osnovnim uporabniškim vmesnikom. Prikazovanje temelji na načelu vzorčne metode, kjer govorimo o zaznavanju med mobilno napravo in obogatenim papirjem. Slednje predstavlja slikovno tarčo v obliki natisnjene interaktivne kartice. Ko kamera mobilne naprave prepozna tarčo, prikaže izbrano žival na mobilnem zaslonu, kjer dobimo rezultat nadgradnje resničnega sveta s 3D-liki. Ob prikazu 3D-lika na zaslonu je s pomočjo uporabniškega vmesnika možno vsako posamezno žival spoznati še v okviru treh različnih animiranih gibanj. Prvi del magistrskega dela je bil izveden v programu Blender, kjer smo ustvarili vse tri živalske 3D-like. Najprej smo morali živali zmodelirati v prepoznavno 3D-obliko, ki smo jim v nadaljevanju prilepili teksture. Sledila je postavitev sistema kosti in animacijskih kontrol, na temelju katerega smo like animirali. Po tem koraku smo delo prenesli v program Unity. V njem smo pripravili platformo, ki omogoča prikazovanje živalskih likov v načinu obogatene resničnosti. Končni rezultati celotnega dela so ustrezno izdelani živalski liki v obliki animiranih 3D-modelov, ki jih je mogoče prikazati v načinu obogatene resničnosti na mobilnih napravah z uporabo interaktivnih kartic. Izbrani parametri testiranja so pokazali, da prihaja do določenih razlik pri predvajanju med obema mobilnima napravama glede na izbrano stopnjo subdivizije 3D-lika. Pri zaznavanju na temelju svetlosti, oddaljenosti in naklona med slikovno tarčo in mobilno napravo je najboljša uporabniška izkušnja dosežena, če je slikovna tarča zajeta iz razdalje 15–20 cm in iz pogleda ptičje perspektive ob dobrih svetlobnih pogojih. This master's thesis is related to two research areas, namely 3D computer graphics and augmented reality, with a combination of their presentation on mobile devices. The thesis presents the creation of three different interactive 3D models based on a realistically drawn image of domestic animals, which can be displayed on mobile devices using augmented reality. The textured animals' models are displayed in an application called Augmented Animals (sl. Obogatene živali) with a simple user interface. The usability of the application is demonstrated by its detection of the image target, i.e. a printed interactive card, which proves the interaction between the mobile device and the augmented paper. When the mobile camera recognizes the target, it displays the selected animal on the screen. The result is an enhancement of the real environment with animated 3D characters. By displaying a 3D character on the screen and interacting with the user interface, the presentation of each animal in three different animated movements is enabled. The first part of this thesis was carried out using the Blender program, where we created all three 3D animal characters. First, we had to model all of the animals from their initial templates into a recognizable 3D shape, to which we then pasted the textures. This was followed by the construction of a system of bones and animation controls, based on which we were able to make animal animations. After this step, we transferred the project to the Unity program, where we constructed an application that is able to show characters in augmented reality. The final result of the entire process are adequately developed animal characters in form of animated 3D models, which can be displayed in the augmented reality mode on mobile devices using interactive cards. The selected testing parameters showed that there are certain differences in presentation between the two mobile devices depending on the selected 3D character subdivision level. However, in terms of detection based on light conditions, distance and inclination between the image target and the mobile device, the best user experience is achieved if the image target is captured from a distance of 15–20 cm, on a bird's eye view and under good lighting conditions.