The effects of coating colours on base papers

Purpose The purpose of this paper is to investigate the influences of coating colours and their contents on the fundamental properties of base papers and also evaluate these results in terms of mechanical and wood-free papers. Design/methodology/approach A design research approach has been based on the application of various coating colours and analysis of mechanical and optical tests results of the coated mechanical and wood-free base papers. Findings This study is confirmed that the coating colours can be easily applied to the surface of the papers. The experimental data have revealed that significant improvements exist in the values of tear resistance (strength), brightness and opacity of the mechanical base papers, especially by the application of the coating colours including kaolin pigment. The results show that mechanical papers can also be used in areas with high brightness expectations by applying coating colour. Originality/value The originality of this work is based on understanding and comparing the effects of applying similar coating formulations on mechanical and wood-free base papers.

Investigation of the Deformation and Strength Properties of Elastomeric Compositions with Urea-Based Additives

The effect of blocked diisocyanates on the elastic-strength properties of elastomeric compositions based on SKI-3 isoprene rubber has been investigated. The synthesized additives are 2-isocyanato-4-phenylcarbamidotoluene (IPCT) and 2,4-diphenylcarbamidotoluene (DPCT). Tests were carried out to determine the physical and mechanical (conditional tensile strength, elongation at break, hardness) properties depending on the type and dosage of additives. It was found that samples with synthesized additives have strength and elongation at break higher than those of a sample without additives by 30 % and 200 %, respectively. There was also an increase in the tear resistance of all samples compared to the control (from 49.9 to 81.9 kN/m). An assumption is made about the formation of a network of physical connections, which provides an increase in these indicators. TMA analysis results showed a wider temperature range for reversible deformations (up to 180 °С).

Tear Resistance and Morphology Study of Tree Pruning Waste Papers: Effect of Soda Pulping Concentration

With the aim to explore the use of tree pruning waste as replacement material in papermaking, a study was conducted to investigate the effect of soda pulping concentration on the tear resistance and surface morphology of the fabricated papers. By varying the sodium hydroxide concentration from 5% to 25%, tree pruning waste papers with different tear resistance and surface morphology were fabricated. The tree pruning waste papers with the optimum tear resistance (73049.68 mN) was produced when the pulping medium was prepared at 20% sodium hydroxide concentration. As confirmed by the morphology study, the pulp fibres with improved interlocking surface morphology was produced at 20% sodium hydroxide concentration. Beyond that, fibre fibrillation had took place and exerted negative impact on the tear resistance of the papers. The present study confirms the use of tree pruning waste as an alternative in papermaking. Nonetheless, the soda pulping concentration must be properly regulated in order to maximize the performance of the fabricated paper products.

ANALISYS OF PAPER RESISTANCE TWO PRODUCT MATTPAPER

Paper is the most widely used print media, made with cellulose fibers derived from tree wood and non-fiber. The existence of paper is a tool that is quite important in human civilization and its needs continue to increase from year to year. The tear resistance of paper greatly affects the printing process. The value of tear resistance is influenced by several factors, namely the size of the fiber, besides that it is also influenced by the number of bonds between the fibers, grammar, humidity, moisture content, fiber direction, adhesive on the paper. The purpose of this final project is to determine the value of paper tear resistance which is better between two types of 120 gram Mattpaper paper products, namely New Victory Luxe and Nevia products and also to determine the effect of paper tear resistance on the printing process. The writing method used is descriptive method with data collection / observation, testing and literature techniques. Based on the results of the tear resistance test with the Elmendorf test method, which is to test the tear resistance of a paper, the tear resistance value of Nevia paper products is better than New Victory Luxe paper products.Keywords—Resistance, Paper, Mattpaper

The utilization of sugarcane bagasse, cassava peels and corn husks in handmade paper production

High demands for trees as the raw material of paper can disrupt the stability of the environment. It is necessary to find alternatives from other materials which are more environmentally friendly. This study aims to determine the quality of paper made from combining sugarcane bagasse with cassava peels or with corn husks using PVAc or tapioca starch adhesives. A completely randomized 2 x 2 factorial design with five times replication was used. The parameters tested were the tensile and tear resistance of the paper using a micrometer and a universal testing machine. A sensory analysis from panelists was also conducted. The combination of J1P1 produced a paper with the highest tensile strength (11.30 MPa) and the highest tear strength (1.82 MPa). The combination of J2P2 produced a paper with the lowest tensile strength (10.35 MPa) and the lowest tear strength (1.62 MPa). Variance analysis showed that the type of adhesive used showed a significant result on both tensile and tear resistance but material choices and interaction between materials and adhesive choices was not significantly different from the result on both tensile and tear resistance. Sensory testing shows that the combination of J1P1 was preferred the most. It can be concluded that the combination of J1P1 appeared to be the best combination.Keywords: Handmade paper, sugarcane bagasse, cassava peels, corn husk, PVAc tapioca starch, adhesive

Impact of Laser Intensities at Various DPI and Pixel Time on the Properties of Denim Garments

This paper investigates the changes in the properties of denim garments with respect to laser intensities of different DPI and Pixel Time. The laser added value to denim garments can fade the outer surface and the yarn portion significantly. In this research, DPI 20 and 25 along with Pixel Time 100, 150 and 200 were applied on samples to investigate the fabric weight, absorbency, crease recovery, tear resistance, tensile strength, pilling and abrasion resistance. For each of the cases, increased DPI and Pixel Time had much greater impact than other parameters on the denim garment samples. After treatment, the fabric sample indicated around 10-30% in weight reduction. The absorbency property of the sample on the other hand showed that higher DPI and Pixel Time required less time to absorb the water on the fabric surface. Furthermore, fabric crease recovery property reduced sharply where maximum 33% crease could not recover after laser exposure. For both tear resistance and tensile strength, especially warp way direction, property reduced more compared to weft way direction due to higher fading effects. After 12,000 cycles, both pilling and abrasion resistance property demonstrated significant reduction for higher laser intensities.

TO THE PROBLEM OF THE INFLUENCE OF THE SCALE EFFECT ON THE TRUE TEAR RESISTANCE OF STEELS

The paper describes the effect of the size of parts on their strength properties, in particular, on the value of the true tensile strength of steels. The use of the obtained dependence for the scale factor allows using the method developed by the authors for determining the true tensile strength of steels for parts of various sizes.