PAPERmaking! FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 2, Number 1, 2016
content. These fines, having a high surface area, restrict the free drainage of water and retain bound water within the pressed sheet but contribute little to the hydrogen bonding potential of the fibre slurry. The advantage of higher freeness, achieved by selective hydrolysis of excess fines through enzymes, can be used for enhancement of the drainage rate, leading to increased paper production. In this study, monocomponent cellulase treatment of recycled pulp for drainage improvement as a result of selective and controlled hydrolysis is investigated. The effectiveness of specific types of enzyme activity, endoglucanase or cellobiohydrolase, is studied. The increased solubilisation of amorphous cellulose mediated by endoglucanase treatments improved pulp drainability by 11 –25 %, along with providing better paper properties such as tensile index and smoothness. Cellulase-assisted refining of bleached softwood kraft pulp for making water vapor barrier and grease-resistant paper, Peng Lu et al , Cellulose , 23 (1). The effect of cellulase pretreatment of bleached softwood kraft fibre before laboratory refining on the water vapour barrier and grease resistance properties of handsheets was investigated in this work. The role of cellulase pretreatment in reducing the WVTR and grease-stained areas was revealed on morphological observation by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, as well as water contact angle testing. TESTING Detailed analysis of the UV-adjustment techniques used in paper and graphic industries, Li Yang, Color Research & Application , online. Many commercial materials (papers and boards) contain optical brightening agents also known as fluorescent whitening agents. Adequate adjustment of the UV content of a measurement device (e.g., spectrophotometer) is essential for accurate colour measurement. As specified in the ISO standards, the UV content is adjusted against an assigned value of an international reference transfer standard, for example, CIE whiteness (D65/10°) for the CIE illuminant D65 or ISO brightness for the C illuminant. Because of the simplicity, these approaches have gained great popularity in papermaking industry. Yet, there has been little evidence indicating how accurate the total spectral radiance factor corresponding to the single assigned value is reproduced. Hence, we present a method that quantitatively evaluates the accuracy of the UV-adjustment technique, through comparing the total spectral radiance factors obtained from UV adjustment with the assigned ones. A novel cup with a pressure-adjusting mechanism for high-temperature water vapor transmission rate measurements, Shinya Iizuka et al , Polymer Testing , online. Water vapour transmission rate measurements with the conventional cup method do not yield accurate values at high temperatures because the film specimens deform and are damaged owing to air expansion in the cup. This article describes a new cup with a pressure-adjusting mechanism allows measurements at 85°C and prevents specimen deformation and damage. WASTE TREATMENT Saccharification of newspaper waste after ammonia fiber expansion or extractive ammonia, Salvatore Montella et al , ABM Express , online. The lignocellulosic fractions of municipal solid waste (MSW) can be used as renewable resources due to the widespread availability, predictable and low pricing and suitability for most conversion technologies. In particular, after the typical paper recycling loop, the newspaper waste (NW) could be further valorised as feedstock in biorefinering industry since it still contains up to 70% polysaccharides. In this study, two different physicochemical methods -
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Technical Abstracts
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