PAPER making! FROM THE PUBLISHERS OF PAPER TECHNOLOGY INTERNATIONAL ® Volume 8, Number 1, 2022
convert paperboards into packages since it enables folding along well-defined lines. The creasing process relies on purpose-made damage that is initiated in the paperboard structure: delamination. However, creasing might also cause in-plane cracks, which must be avoided. In this laboratory study, three paperboards were creased at six different depths, respectively. Two mechanical tests were performed to characterize the creases at standard climate (23°C and 50% RH): 2-point folding, to examine the bending force and short-span in-plane tensile test to evaluate the strength. The results were normalized with the values for the uncreased boards, which gave the relative strength ratios: relative creasing strength (RCS) and relative tensile strength (RTS). When the relative strengths were evaluated against the normative shear strains, a creasing window was formed. This window has an upper limit given by the RTS values, corresponding to the in-plane cracks, and a lower limit given by the RCS values, corresponding to the delamination damage initiated in the paperboard during creasing. It was observed that both the RCS and RTS values exhibit a linear relation against normative shear strain. From this, it was concluded that performing tests at two creasing depths might be sufficient to estimate the lower, and upper, limits for the creasing window in future studies. Finally, the effect of moisture was investigated by creasing, folding and tensile testing at 23°C and 90% RH, which showed that moisture had no clear effect on the RCS or the RTS values. TISSUE “ Application of additives to manufacture quality towel grade tissue paper with accelerated productivity ”, Sanjeev Kumar Jain, Dharam Dutt & R.K. Jain, Materials Today Proceedings , (2021) online. Nowadays in paper business sector there is only tissue paper business where growth rate is in double digits since five years consecutively which motivates and encourage entrepreneurs to take up the business with more vigor. Tissue paper is generally categorized in four grades - Napkin grade paper, Toilet grade paper, Facial grade paper and Towel grade paper. Due to higher consumption of towel grade tissue paper at several outlets like offices, educational institutions, aesthetic purposes, common toiletries and hospitalities. This towel grade is being used for wiping wet hands, to meet out these requirements we need to develop high strength in towel grade tissue paper. This study is being conducted to high strength in towel grade tissue paper with application of DSR and WSR. Chemical additives play essential role in production performance of towel grades tissue paper. A significant amount of their tensile strength are retained by wet and dry strength resins. Mixed bleached pulp was collected from pulp mill of a well-known industry. It was refined to different degrees of freeness (°SR) i.e. 25, 30 and 35. Handsheets of pulp refined to different extent, were prepared and physical properties investigated. Based on the specific energy consumption of refiner and the pulp strength properties obtained, pulp freeness with 35°SR were selected for further study. DSR was added in three different doses i.e. 2.0, 3.0 & 4.0 kg/ton and WSR in dosages of 15, 25 & 35 kg/t of pulp. Breaking length and wet strength were enhanced by 32 % and 42 % respectively. On account of this, significant reduction in paper breaks observed on paper machine, which further improved machine runability, reducing downtime. Productivity of machine was enhanced along with supreme quality of towel (interfold) grade tissue paper. “Computational Simulation Tools to Support the Tissue Paper Furnish Management: Case Studies for the Optimization of Micro/Nano Cellulose Fibers and Polymer- Based Additives”, Flávia P. Morais, Ana M. M. S. Carta , Maria E. Amaral & Joana M. R. Curto, Polymers , Vol.13(22), (2021). Tissue paper production frequently combines two main types of raw materials: cellulose fibers from renewable sources and polymer-based additives. The development of premium products with improved properties and
Technical Abstracts
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