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The use of mineral-based fillers tends to reduce the mechanical properties of paper, which can limit their application. The filler surface modification is a significant treatment to overcome this limitation. This research aims to offer a novel modified mineral-based filler to provide its industrial application. The surface of precipitated calcium carbonate (PCC) was modified with xylan (XS), which is a type of hemicellulose, a polysaccharide consisting mainly of xylose residues. It is used as a filler at different filler dosage levels in paper pulp. Modified PCC(MPCC) was characterized with Fourier transform infrared spectroscopy, Thermogravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction and Field-emission scanning electron microscopy analyses. The analysis demonstrated that the MPCC filler surface was coated with XS successfully. The effect of PCC and MPCC-filled hand-sheet paper physical, chemical and optical properties were studied. The experimental results showed that the mechanical (tensile, burst, tear strength) and optical (brightness, opacity) of hand-sheet paper filled with MPCC were significantly improved compared with unmodified PCC-filled paper at the same ash content. The filler retention of PCC and MPCC fillers in paper was investigated, and the MPCC filler showed better filler retention properties in paper stock than the PCC filler. [ABSTRACT FROM AUTHOR]

A small framed display panel holds a selection of paper and media common in works on paper plus a set of Blue Wool Standards. The selection of materials and design of the panel including two types of glazing are presented, and the purpose of the panel as a tool for explaining the effects of light on materials is discussed. At the centre of the panel are watercolour samples prepared using primary colours in mixed washes that illustrate hue shift resulting from selective fading of one colourant. [ABSTRACT FROM AUTHOR]

The main aim of the present research is to examine the effect of progressive deinking and reprinting on the paper properties of inkjet-printed paper. A typical office copy paper was selected as the base paper and printed using an inkjet printer having at least 50 % ink coverage. Thereafter, it was deinked and reprinted thrice, and its paper properties were measured. The paper properties that were measured were roughness, porosity, opacity, brightness, specular gloss, whiteness, bursting strength, tearing resistance, tensile strength, contact angle, deinkability efficiency, visible dirt area, ink elimination factors, and color differences. The results showed that in comparison to the base paper, the progressively deinked and reprinted paper samples showed an increase in roughness, porosity, opacity, tearing resistance, dirt area, and color difference. On the other hand, there was a decrease in brightness, gloss, whiteness, burst strength, tensile strength, contact angle, deinkability efficiency, and ink elimination factors. The experiment shows that the progressively deinked and reprinted papers can be compared to the base paper in the major paper properties. [ABSTRACT FROM AUTHOR]

A novel paper multifunctional protective solution was prepared by mixing berberine modified trimethoprimed carboxymethyl cellulose (TMP-DCMC-BBR), KH-791 modified nano-SiO2 (KH791-SiO2) and hydroxypropyl starch phosphate (HPDSP), and the mechanical properties, optical properties, antibacterial properties, aging resistance, acid and alkali resistance of the paper coated with the protective solution were investigated. It is shown that the paper coated with the multifunctional protective liquid showed good mechanical properties, and has little influence on optical properties of the paper. At the same time, it had good antibacterial properties, aging resistance and acid and alkali corrosion resistance, and there is no obvious change in paper appearance, no decolorization and ink diffusion, which is in line with the principle of "repairing the old as the old and keeping the original appearance". Moreover, the compound solution has certain reversibility and can absorb a certain degree of ultraviolet rays, so as to weaken the damage of ultraviolet rays to the paper. It is an ideal multifunctional protective liquid for paper and has broad application prospects in paper protection. [ABSTRACT FROM AUTHOR]

The pulp and paper industry is increasingly seeking a sustainable and conscientious development, minimizing the environmental impacts caused by it. Therefore, reducing efficiently the number of stages used in the bleaching process can mean less consumption of water and chemical reagents, contributing to the reduction of harmful waste to the environment. Thus, this study sought to evaluate the pulp quality and some physical-mechanical properties (smoothness, tear and tensile indexes) of two new bleaching sequences A*DP and A*E*DP and compare them with the reference D0(E+P)D1P. To do so, industrial eucalyptus Kraft pulp pre-delignified with oxygen was used. The bleached pulp was refined to 1200, 1800 and 2400, in PFI mill and tested according to TAPPI standards to determine smoothness, tear and tensile indexes. Based on the results obtained, it was verified that the sequences studied are viable for using in bleaching plants, which allowed a reduction in the chlorine dioxide consumption and presented satisfactory smoothness, tear and tensile indexes for paper. [ABSTRACT FROM AUTHOR]