Art Paper for Large Wood Relief Block Printing – A Paper Development Study

Wood relief block printing was developed in China in the seventh century and is used today for many art printing applications. The presented research project describes the development of an art paper product applicable for large wood relief block printing from laboratory scale to large semi commercial production of art paper for printing image sizes of up to 44-inch (1118 mm) by 96-inch (2400 mm) at outdoor steam roller printing events or smaller indoor printing press applications. The improvement of the paper properties from laboratory development, small laboratory paper machine and semi commercial paper machine run for the production of the final art paper showed an improvement throughout the process development for the optical and mechanical paper properties and exceeded the set values set by the artist using the art paper. The produced art paper with a basis weight of 260 g/m² and a thickness of 171 µm is produced from a mixture of 70% northern bleached hardwood Kraft pulp and 30% northern bleached softwood Kraft pulp. The ISO brightness of the art paper off-white (egg-shell) colour was at 63.2% and the ISO color value for L, a, b. at 90.8, 1.1, and 12.6 respectively. The art papers surface roughness and porosity as a parameter for ink attachment and penetration is for the top side 2179 ml/min and for the bottom side (wire side) 2326 ml/min, whereas porosity was measured at 1668 ml/min. Bending stiffness in machine direction and cross machine direction was measured at 157mN and 70 mN respectively. Burst strength was measured at 2.24 kPA·m²/g.

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Effect of machine speed on formation and strength efficiency in twin-wire roll forming of never-dried unbleached softwood kraft pulp

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2018-3038 ◽

2018 ◽

Vol 33 (2) ◽

pp. 271-278

Author(s):

Bengt Nordström ◽

Lennart Hermansson

Keyword(s):

Tensile Strength ◽

Kraft Pulp ◽

Roll Forming ◽

Favorable Effect ◽

Paper Properties ◽

Difference Curve ◽

Insignificant Effect ◽

Wide Range ◽

Softwood Kraft Pulp ◽

Machine Speed

Abstract There is a constant drive to increase machine speed in the production of kraftliner and most other major paper grades, but the separate effect of the machine speed on the paper properties has been unclear. The effect of machine speed in twin-wire roll forming of never-dried unbleached softwood kraft pulp was evaluated here in a pilot machine investigation by examining three machine speed levels (500, 750, and 1000 m/min) over a series of jet-to-wire speed differences. Similar headbox consistency and draw from wire section to winding were employed at the different machine speed levels. An increase in the machine speed had a favorable effect on formation and Z-strength efficiency over a wide range of jet-to-wire speed differences, whereas the machine speed had an insignificant effect on tensile strength efficiency and tensile stiffness efficiency. For all properties, the overall shape of the jet-to-wire speed difference curve remained similar when changing the machine speed.

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The Effects of Recombinant Cellulomonas fimi β-1,4-glycanases on Softwood Kraft Pulp Fibre and Paper Properties

Progress in Biotechnology - Biotechnology in the Pulp and Paper Industry - 8th ICBPPI ◽

10.1016/s0921-0423(02)80033-8 ◽

2002 ◽

pp. 301-310 ◽

Cited By ~ 3

Author(s):

Shawn D. Mansfield ◽

Neil R. Gilkes ◽

R. Antony J. Warren ◽

Douglas G. Kilburn

Keyword(s):

Kraft Pulp ◽

Paper Properties ◽

Cellulomonas Fimi ◽

Pulp Fibre ◽

Softwood Kraft Pulp

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Effect of reduced pulp xylan content on wet end chemistry and paper properties — a pilot scale study

TAPPI Journal ◽

10.32964/tj13.2.29 ◽

2014 ◽

Vol 13 (2) ◽

pp. 29-37 ◽

Cited By ~ 1

Author(s):

KATJA LYYTIKÄINEN ◽

ESA SAUKKONEN ◽

MARKKU VÄISÄNEN ◽

JUSSI TIMONEN ◽

KAJ BACKFOLK

Keyword(s):

Kraft Pulp ◽

Scale Up ◽

Pilot Scale ◽

Partial Replacement ◽

Paper Machine ◽

Charge Balance ◽

Paper Properties ◽

Birch Kraft Pulp ◽

Positive Effect ◽

Xylan Content

In this scale-up study, we examined the effects of using varying amounts of fibers with reduced xylan content in paper. Bleached birch kraft pulp was partially or fully replaced by alkali-extracted pulp, and the effects of this replacement on the wet end chemistry of the paper machine and the resulting paper properties were determined. Our results show that paper properties can be maintained or improved when optimizing the partial replacement of bleached birch kraft pulp with alkali-extracted pulp. The incorporation of alkali-extracted pulp in paper machine stock had a positive effect on first pass retention and retention of chemicals. However, careful optimization of chemical dosages is required because of the altered charge balance in the wet end.

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Softwood kraft pulp fines: application and impact on specific refining energy and strength properties

Cellulose ◽

10.1007/s10570-020-03467-1 ◽

2020 ◽

Vol 27 (17) ◽

pp. 10359-10367

Author(s):

Daniel Mandlez ◽

Lukas Zangl-Jagiello ◽

Rene Eckhart ◽

Wolfgang Bauer

Keyword(s):

Tensile Strength ◽

Linear Relationship ◽

Apparent Density ◽

Kraft Pulp ◽

Strength Properties ◽

Air Permeability ◽

Research Interest ◽

Paper Properties ◽

Softwood Kraft Pulp ◽

Breaking Length

AbstractAlong with the emergence of micro and nanofibrillated celluloses and their application in papermaking, the influence of the so called fines fraction of pulps on both process and product properties has received increasing research interest in recent years. Several researchers have experimented with primary and/or secondary pulp fines to assess their effects on paper properties with not always consistent results. Our work focuses on the targeted application of the primary fines fraction of an unbleached softwood kraft pulp. The primary fines are separated from the pulp to be subsequently added to achieve blends of $$5\%, 9\%$$ 5 % , 9 % and $$12\%$$ 12 % primary fines content. These blends were then refined in a PFI mill to evaluate the effect of the primary fines on refining as well as on paper properties of hand sheets prepared from these pulps. It is shown that the addition of primary fines enhances tensile strength in the unrefined and slightly refined state, while the maximum tensile strength of the highly refined reference pulp is not increased. A slightly increased dewatering resistance (Schopper Riegler) at comparable air permeability (Gurley) for a given tensile strength was also observed. The linear relationship between tensile index and apparent sheet density seems to be affected in the unrefined and slightly refined state where the breaking length of the fines enriched samples is higher for a given apparent density.

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Three-dimensional visualization and characterization of paper machine felts and their relationship to their properties and dewatering performance

TAPPI Journal ◽

10.32964/tj20.7.23 ◽

2021 ◽

Vol 20 (7) ◽

pp. 423-435

Author(s):

CAROLINE FRISCHMON ◽

JOHN XU ◽

SHRI RAMASWAMY

Keyword(s):

Size Distribution ◽

Structural Characteristics ◽

Three Dimensional ◽

Structural Features ◽

Chemical Compositions ◽

Water Removal ◽

Paper Machine ◽

Machine Direction ◽

Paper Properties ◽

Permeability Characteristics

Polymeric felts are commonly used in the papermaking process on the paper machine wet end, in the press section, and in the dryer section. They provide an important function during paper manufacturing, including as a carrier or support; as a filter media assisting with water removal on the paper machine; in retention of fibers, fines, and fillers; and in some applications, such as tissue and towel, to impart key structural features to the web. These felts can have highly interwoven complex internal structures comprised of machine direction and cross-machine direction yarns of varying sizes and chemical compositions. Here, we present a non-intrusive three-dimensional (3D) image visualization method using advanced X-ray computed tomography (XRCT). This method was used to characterize the complex 3D felt structure and determine the water removal characteristics of some commonly used paper machine felts. The structural features analyzed include porosity; specific pore-yarn interfacial surface area; 3D pore size distribution; 3D fiber or yarn-size distribution; and their variations through the thickness direction. The top, middle, and bottom layers of the felt have very different structures to assist with water removal and impart paper properties. The size distribution of the yarns, as well as the pores in the different layers of the felt, are also inherently different. These structural features were non-intrusively quantified. In addition, variation in the structural characteristics through the thickness of the felts and its potential role in papermaking is explored. In addition to the 3D structural characteristics, permeability characteristics and water removal characteristics, including rewetting of select felt samples, have also been experimentally determined. It is interesting to observe the relationship between key structural features and permeability and water removal characteristics. These relationships can provide additional insights into press felt design, as well as ways to improve product properties and the dewatering efficiency and productivity of the paper machine.

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Optimization of elemental chlorine-free bleaching for a softwood kraft pulp • part 2: economic analysis of chemical and steam consumption

TAPPI Journal ◽

10.32964/tj9.9.47 ◽

2010 ◽

Vol 9 (9) ◽

pp. 47-53 ◽

Cited By ~ 2

Author(s):

BRIAN N. BROGDON

Keyword(s):

Chlorine Dioxide ◽

Previous Investigation ◽

Kraft Pulp ◽

Energy Costs ◽

Alkaline Extraction ◽

Stage Versus ◽

Kraft Pulps ◽

Steam Consumption ◽

Elemental Chlorine ◽

Softwood Kraft Pulp

Our previous investigation [1] re-analyzed the data from Basta and co-workers (1992 TAPPI Pulping Conference) to demonstrate how oxidative alkaline extraction can be augmented and how these changes affect chlorine dioxide consumption with elemental chlorine-free (ECF) sequences. The current study manipulates extraction delignification variables to curtail bleaching costs with a conventional U.S. Southern softwood kraft pulp. The economic advantages of ~0.35% to 0.65% H2O2 peroxide reinforcement in a 70°C (EOP)-stage versus 90°C (EO)-stage are predisposed to the brightness targets, to short or long bleach sequences, and to mill energy costs. Minimized bleaching costs are generally realized when a 90°C (EO) is employed in D0(EO)D1 bleaching, whereas a 70°C (EOP) is economically advantageous for D0(EOP)D1E2D2 bleaching. The findings we disclose here help to clarify previous ECF optimization studies of conventional softwood kraft pulps.

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An effective method for determining the retention and distribution of cellulose nanofibrils in paper handsheets by dye labeling

TAPPI Journal ◽

10.32964/tj17.03.157 ◽

2018 ◽

Vol 17 (03) ◽

pp. 157-164 ◽

Cited By ~ 3

Author(s):

Shengdan Wang ◽

Wenhua Gao ◽

Kefu Chen ◽

Jinsong Zeng ◽

Jun Xu ◽

...

Keyword(s):

Correlation Coefficient ◽

Congo Red ◽

Kraft Pulp ◽

Cellulose Nanofibrils ◽

Standard Curve ◽

Congo Red Dye ◽

Mechanical Disintegration ◽

Softwood Kraft Pulp ◽

White Water ◽

Red Dye

Cellulose nanofibrils (CNF) were prepared by cellulase in conjunction with mechanical disintegration from the bleached softwood kraft pulp and labelled by Congo red dye. The labelled CNF were used to investigate the retention and distribution of CNF in paper handsheets. The retention of the labelled CNF was obtained by measuring the absorbance of white water using an ultraviolet-visible spectrophotometer. The results showed that this method for measuring the retention was rapid, feasible, and sensitive, owing to the high correlation coefficient R2 (0.9993) of the standard curve. The labelled CNF showed even distribution in paper handsheets. The colorimetric values of paper handsheets were explored with a residual ink analyzer.

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