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Öğe Effect of oil based CMYK process inks on tearing characteristics of paper(2015) Atik, Celil; Engin, Merve; Aydemir, Cem; İmamoğlu, SamiGünlük yaşamda yırtılma direncine maruz kalan birç ok baskılı malzemeyi kullanmaktayız. Kâğıt ve baskı mürekkebi arasındaki etkileşimler lifler arası bağları ve dolayısıyla kâğıdın yırtılma direncini etkiler. Bu çalışmada Cyan, Magenta, Sarı ve Siyah renk yağ bazlı ofset proses mürekkepleri kullanılarak ya pılan zemin ton baskılarının kağıdın yırtılma direncine etkileri belirlenmeye çalışıldı. Kâğıdın statik yırtılma direnci, evrensel çekme testi cihazı kullanılarak belirlenmiştir ve yırtılma direnci modelleri incelenmiştir. Basılı kâğıtlarda yırtılma direnc inin azalması ve nispeten yakın yırtılma endeksi oranları (çapraz yön/makine yönü) gözlemlenmiştir. Yağ bazlı mürekkeplerle zemin tonlu baskı uygulaması, kâğıtların yırtılmaya başlaması için gerekli olan gücü arttırmıştır.Öğe EFFECT OF USING CALCIUM CARBONATE (CaCO3) IN SURFACE COATING ON LIQUID ABSORPTION OF PAPER AND SOME PRINTABILITY PARAMETERS(Editura Acad Romane, 2020) Kandırmaz, Emine Arman; Yenidoğan, Semiha; Aydemir, Cem; Karademir, ArifFor quality printing results that require detail, the smooth paper surface, absorbency, color and gloss are of great importance. Since the desired surface properties cannot be obtained even in well-polished paper, smooth paper surfaces can be obtained by sizing and coating processes. The aim of this study was to investigate the effect of different amounts of calcium carbonate, added into the surface coating formulation, on liquid absorbency and printability of paper. Paper coating formulations were created by adding 1%, 2.5%, 5% and 7.5% calcium carbonate to an equal amount of cationic starch binder. The obtained coating formulations were applied to the surface of standard pieces of paper with a lab coater. Water absorbency and drop contact angle of all papers (base paper and surface-treated paper) were measured by using the sessile droplet method and then their surface energies were calculated. After the gloss and color changes of the test papers were determined, test prints were applied on their surface with offset printing ink. The effect of surface treatments on the printability characteristics of the paper was examined in detail. It was emphasized that the amount of calcium carbonate used in cationic starch should be optimized with regard to the absorbency and printability of the paper.Öğe Effects of color mixing components on offset ink and printing process(Taylor & Francis Inc, 2017) Aydemir, Cem; Yenidogan, Semiha; Karademir, Arif; Arman, EmineIn printing, the most important element is to obtain the correct substrate and ink combination. Transparent white and opaque white are used for the lightening of printing inks, but they are also an important component for the mixing of inks. The primary objective of this study was to assess the result of using transparent and opaque white in mineral oil-based offset printing inks on the rheological and printability properties of these inks as well as the ideal mixing ratios in terms of print quality. Transparent and opaque white were added into the standard offset magenta ink variable ratios. Differences in ink viscosity, tack, and flow (rheological) values affect such parameters as adhesion, transferability, and printing stability in these inks. Prints were made on matt-coated papers of the same grammage with these inks, and contact angle, solid ink density, color strength, and print gloss values of these ink films were measured. Color differences (Delta E*(ab)) of inks in comparison to the standard ink were calculated and the effects of transparent and opaque white on the rheological and printability properties of the ink were presented. Finally, the ideal mixture ratios of transparent and opaque white into the ink were determined in terms of print quality and recommendations were presented.Öğe Effects of Flotation Deinking on the Removal of Main Colors of Oil-Based Inks from Uncoated and Coated Office Papers(North Carolina State Univ Dept Wood & Paper Sci, 2013) İmamoğlu, Sami; Karademir, Arif; Pesman, Emrah; Aydemir, Cem; Atik, CelilThis paper presents the results of trials to evaluate the color-stripping behaviour of offset printing colors and the effect of coating on deinking performance. Oil-based four-color inks were separately printed as base printing on coated and uncoated white poster paper, and then extensive pulping and deinking processes were carried out. Standard offset printings were conducted on paper samples using cyan, magenta, yellow, and black colors (CMYK), and the effects of deinking efficiency on the removal of each color were analysed. The pulps were made at Micro-Maelstrom Laboratory Pulper at specified conditions with and without bleaching agents. Formamidin sulfinic acid and hydrogen peroxide formulation were used as reductive and oxidative bleaching agents, respectively. Flotation deinking and thickening of pulp were practiced using Degussa flotation and thickening cell. The changes in the optical properties, such as brightness, whiteness, and color value (CIE L*, a*b*) of deinked pulp were determined. It was found that optical properties of color-stripped pulps from coated papers were better than that of uncoated office papers. However, yield was quite low in coated papers since fillers were lost during flotation process. Cyan color was found to be the most difficult one in four main color printing inks stripping out in deinking process.Öğe Effects of matte coating on the paper surface and print density(Walter De Gruyter Gmbh, 2013) Aydemir, Cem; Ozomay, Zafer; Karademir, Arif; Kandirmaz, Emine ArmanIn this work, standard laboratory printing applications with IGT (ISO 12647-2) were applied on uncoated and matte-coated papers using offset inks (DIN ISO 2846-1). Surface roughnesses of uncoated and coated sheets were recorded to be 195 and 13 ml/min, respectively. Air permanence values of uncoated and coated papers were found to be 5.6 and 0.103 mu m/Pa.s, respectively. Changes in the print densities were recorded up to 48 h. Print density changes for uncoated and matte-coated papers were surprisingly found to be in similar paths (8% in the first 4 h), although significant differences between surface roughnesses were recorded. Furthermore, paper samples showed similar behaviors for the percent volume changes, where drop volume disappeared within 6 min. It is concluded that matte coating did not have any significant effects on print density change and drop volume change.Öğe EXAMINATION OF THE IMPACT OF DRYING TECHNIQUES IN SURFACE SIZING-COATING OPERATIONS ON THE QUALITY OF PAPER AND PRINTING(Editura Acad Romane, 2019) Yenidogan, Semiha; Aydemir, Cem; Karademir, Arif; Kandirmaz, Emine ArmanIn order to improve the surface characteristics of paper, surface sizing and surface coating are applied to the surface of the paper. Filling the pores on the surface with polymerized substances and flatting the surface are aimed in both operations. Test papers are either left for air-drying or they could be heated in an oven to dry more quickly. Other drying techniques may also affect printing, as well as the optical and physical qualities of the paper. In this study, starch-based sizing and calcium carbonated-starch-based coating operations were applied separately on paper surfaces. Some of the papers were allowed to dry at room temperature, and the others were dried in an oven. When the drying process was completed, paper gloss, water absorption and wettability qualities, as well as the CIE L*a*b* color coordinates of all the papers were evaluated. In the following stage of the study, solid tone printing was applied on the surfaces of the papers - that had been subjected to different drying processes - using cyan colored ink in an IGT C1 printability tester. The effects of air-drying and oven-drying techniques in surface coating and sizing operations on the physical and printability characteristics of the paper were evaluated.Öğe The examination of vegetable- and mineral oil-based inks' effects on print quality: Green printing effects with different oils(Sage Publications Ltd, 2018) Aydemir, Cem; Yenidogan, Semiha; Karademir, Arif; Kandirmaz, Emine ArmanIntroduction: Printing inks oil selection is related to the desired nature of the varnish in the ink production. Petroleumderived mineral oils and vegetable oils can be used in offset inks. Methods: In this study, the behaviors of vegetable- and mineral oil-based inks on uncoated and coated paper surfaces were investigated in terms of printability. Solid tone test prints were done with offset printing of these inks. Print gloss of the printed samples was measured and a light fastness test was implemented on these samples in order to determine the resistance to fading. Absorption behavior and contact angles of the ink-printed films on the test papers were measured with the sessile water drop method depending on time, and surface energies were calculated. Results: On both paper types, linseed-soybean oil-based vegetable ink gave the highest brightness value. The lowest print gloss results on the paper were obtained from soybean oil-based inks. The lowest color change was recorded with mineral oil-based inks on gloss-coated papers. According to the ink-film-surface relation, when the contact angle is high, surface energy decreases and the absorbency of the ink-film is lower. Conclusions: In this study, the behaviors of vegetable- and mineral oil-based inks on different paper surfaces, and the effect on the quality of printability as well as differences, have been evaluated, taking environmental and health factors into consideration.Öğe Investigation of the evolution of hydrophobicity and wettability of paper in multi-color printing process(Editura Acad Romane, 2019) Aydemir, Cem; Karademir, Arif; İmamoğlu, Sami; Altay, Bilge Nazli; Fleming, Paul D.; Tutak, DoganOne of the keys to improving print quality is to experimentally characterize the paper surface, structure and printability to obtain quality control mechanisms. In multi-color prints, determining the differences in the acceptance of the next color ink by the surface of the paper or the ink film that was previously printed is important for print quality. The criteria, such as ink setting, adhesion, color, gloss and density, in the printing process, depend on the wettability and absorbency of the paper. The surface structure of the paper is the most important factor in determining the hydrophobic properties. In this study, wetting and absorption dynamics of the printed partially hydrophobized paper surface were investigated. The aim was to measure the effect of the printed ink film on the wetting (surface free energy) and liquid absorption behavior of the paper. Liquid absorption changes on printed/unprinted paper surfaces were measured by the sessile drop method, using a contact angle-measuring device. The surface energies of the papers were calculated and evaluated according to the surface contact angle of the droplet.Öğe Printability of papers recycled from toner and inkjet-printed papers after deinking and recycling processes(Sage Publications Ltd, 2018) Karademir, Arif; Aydemir, Cem; Tutak, Dogan; Aravamuthan, RajaBackground: In our contemporary world, while part of the fibers used in the paper industry is obtained from primary fibers such as wood and agricultural plants, the rest is obtained from secondary fibers from waste papers. To manufacture paper with high optical quality from fibers of recycled waste papers, these papers require deinking and bleaching of fibers at desired levels. High efficiency in removal of ink from paper mass during recycling, and hence deinkability, are especially crucial for the optical and printability quality of the ultimate manufactured paper. Methods: In the present study, deinkability and printability performance of digitally printed paper with toner or inkjet ink were compared for the postrecycling product. To that end, opaque 80 g/m(2) office paper was digitally printed under standard printing conditions with laser toner or inkjet ink; then these sheets of paper were deinked by a deinking process based on the INGEDE method 11 p. After the deinking operation, the optical properties of the obtained recycled handsheets were compared with unprinted (reference) paper. Then the recycled paper was printed on once again under the same conditions as before with inkjet and laser printers, to monitor and measure printing color change before and after recycling, and differences in color universe. Results: Recycling and printing performances of water-based inkjet and toner-based laser printed paper were obtained. The outcomes for laser-printed recycled paper were better than those for inkjet-printed recycled paper. Conclusions: Compared for luminosity Y, brightness, CIE a* and CIE b* values, paper recycled from laser-printed paper exhibited higher value than paper recycled from inkjet-printed paper.Öğe Printability of papers recycled from toner and inkjet-printed papers after deinking and recycling processes (vol 16, pg 76, 2017)(Sage Publications Ltd, 2018) Tutak, Dogan; Karademir, Arif; Aydemir, Cem; Aravamuthan, Raja[No Abstract Available]Öğe The use of natural (Pinus pinaster) resin in the production of printing ink and the printability effect(Wiley, 2020) Karademir, Arif; Aydemir, Cem; Yenidogan, Semiha; Arman Kandirmaz, Emine; Kiter, Rukiye G.Alkyd resins are generally used in the production of printing inks. All industries look for alternative raw materials in the production of ink with the growing inclination toward using natural products. Resins forming the vehicle of the ink to be obtained from natural resources will provide benefits for the environment, nature, and living creatures. The aim of the study was to promote the use of natural resin in the ink system. NaturalPinus pinasterresin was added into vegetable and mineral oil-based solvents in pure form with alkyd resin in different amounts and ink varnishes of different combinations were prepared. Then, printing inks were produced from these varnishes in pure and hybrid form. Following the assessment of the rheological properties of the inks prepared, printing tests were conducted to assess the printing quality parameters. Ideal mixing ratios of the natural resins in the ink were determined for printability. The environmental importance and advantages of the use of natural resins were discussed. Recommendations were given in line with the results to encourage widespread use of natural resins in near future.
