DOCSLIB.ORG

Electrical and Dielectric Properties of Uncoated and Coated Wood-Free Paper for Electrophotography

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Electrical and Dielectric Properties of Uncoated and Coated Wood-Free Paper for Electrophotography Petri Sirviö | Electrical and Dielectric Properties of Uncoated and Coated Wood-Free Paper for Electrophotography | 2016 Electrophotography for Paper SirviöWood-Free Petri | Electrical and Dielectric and Coated of Uncoated Properties Petri Sirviö Electrical and Dielectric Properties of Uncoated and Coated Wood-Free Paper for Electrophotography 9 789521 234163 ISBN 978-952-12-3416-3 Electrical and Dielectric Properties of Uncoated and Coated Wood-Free Paper for Electrophotography Petri Sirviö Laboratory of Physical Chemistry Faculty of Science and Engineering Åbo Akademi University Åbo, Finland 2016 Supervised by Professor Jouko Peltonen, Professor Emeritus Jarl B. Rosenholm and Adjunct Professor Kaj Backfolk Laboratory of Physical Chemistry, Åbo Akademi University, Turku, Finland Reviewed by Professor Øyvind W. Gregersen Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim, Norway and Professor Arved C. Hübler Institute of Print and Media Technology, Chemnitz University of Technology, Chemnitz, Germany Dissertation opponent Professor Øyvind W. Gregersen Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim, Norway ISBN 978-952-12-3416-3 Painosalama Oy – Turku, Finland 2016 PREFACE The research summarized in this thesis has been conducted as a part of the research programs of Stora Enso Oyj to develop paper and board substrates for the electrophotographic printing processes in partnerships with several universities. The main part of the summarized research work has been done in Stora Enso’s R&D facilities and in cooperation with Åbo Akademi University and Vilnius University. I would like to thank the personnel involved in these institutions for their advice, expertise, and knowledge. In particular, I would like to thank professors Jarl B. Rosenholm and Jouko Peltonen from Åbo Akademi University, professor Kaj Backfolk from Lappeenranta University, and professors Jonas Sidaravicius and Robertas Maldzius from Vilnius University. The level of knowledge and experience accumulated into this group is indeed convincing and I am proud to have had the opportunity to work in such teams during the scientific part of my career. I would also like to thank all the authors and co- authors in the publications included in this thesis as well as those in the supporting publications. I am grateful for all the interesting work we have done, for all the interesting discussions, and for all that we have learned. Stora Enso Oyj is acknowledged for its vision of exploring new areas. The Finnish Funding Agency for Innovation TEKES is acknowledged for the financial support for this research. Finally, I would like to thank my wife Leena for her crucial support, which has made everything possible. I wish to dedicate this work to her. 3 CONTENTS ABSTRACT.............................................. ........................................................................................... 6 SVENSK SAMMANFATTNING ....................................................................................................... 7 LIST OF PUBLICATIONS ................................................................................................................. 8 SUPPORTING PUBLICATIONS ....................................................................................................... 9 1. INTRODUCTION ...................................................................................................................... 11 2. OBJECTIVES ............................................................................................................................. 12 3. LITERATURE REVIEW ........................................................................................................... 12 3.1 Effect of substrate topography on toner transfer ...................................................................... 12 3.2 Electrical resistivity and dielectric properties of paper and the effect of electric field on electrical resistivity......................................................................................................................... 13 3.3 Charging and charge decay of paper ........................................................................................ 15 3.4 Effect of coating ....................................................................................................................... 16 4. EXPERIMENTAL ...................................................................................................................... 17 4.1 Materials ................................................................................................................................... 17 4.1.1 Paper samples and coating formulations for determining the effect of roughness on toner transfer ........................................................................................................................................ 17 4.1.2 Paper samples for resistivity, charging, charge decay, and dielectric measurements ....... 18 4.2 Methods .................................................................................................................................... 19 4.2.1 Measurement of paper topography, roughness, print quality, and toner transfer .............. 19 4.2.2 Measurement of paper resistivity....................................................................................... 20 4.2.3 Measurement of charge acceptance and charge decay of paper ........................................ 20 4.2.4 Measurement of dielectric properties of paper .................................................................. 21 5. RESULTS AND DISCUSSION ................................................................................................. 22 5.1 Effects of substrate topography and moisture content on electrophotographic toner transfer . 22 5.2 Electrical resistivity/conductivity of paper............................................................................... 26 5.2.1 Dependency on electric field ............................................................................................. 26 5.2.2 Effect of NaCl and moisture content ................................................................................. 29 5.2.3 Effect of temperature ......................................................................................................... 31 5.2.4 Effects of coat weight and base paper on conductivity ..................................................... 33 5.3 Dielectric properties of paper ................................................................................................... 35 5.3.1 Influence of moisture and ion contents .............................................................................. 35 5.3.2 Influence of temperature .................................................................................................... 38 4 5.3.3 Influence of coating ........................................................................................................... 41 5.4 Charging and charge decay of paper ........................................................................................ 42 5.4.1 Charge acceptance ............................................................................................................. 42 5.4.2 Charge decay ..................................................................................................................... 43 5.4.3 Temperature vs. charging and charge decay ...................................................................... 45 6. CONCLUSIONS ........................................................................................................................ 48 7. REFERENCES ........................................................................................................................... 50 Publications I - VI 5 ABSTRACT The print substrate influences the print result in dry toner electrophotography, which is a widely used digital printing method. The influence of the substrate can be seen more easily in color printing, as that is a more complex process compared to monochrome printing. However, the print quality is also affected by the print substrate in grayscale printing. It is thus in the interests of both substrate producers and printing equipment manufacturers to understand the substrate properties that influence the quality of printed images in more detail. In dry toner electrophotography, the image is printed by transferring charged toner particles to the print substrate in the toner transfer nip, utilizing an electric field, in addition to the forces linked to the contact between toner particles and substrate in the nip. The toner transfer and the resulting image quality are thus influenced by the surface texture and the electrical and dielectric properties of the print substrate. In the investigation of the electrical and dielectric properties of the papers and the effects of substrate roughness, in addition to commercial papers, controlled sample sets were made on pilot paper machines and coating machines to exclude uncontrolled variables from the experiments. The electrical and dielectric properties of the papers investigated were electrical resistivity and conductivity, charge acceptance, charge decay, and the dielectric permittivity and losses at different frequencies, including the effect of temperature. The objective was to gain an understanding of how the electrical and dielectric properties are affected by normal variables in papermaking,
Load more

Recommended publications
  • DOI: 10.1002/ ((Please Add Manuscript Number)) Article Type: Full Paper
    DOI: 10.1002/ ((please add manuscript number)) Article type: Full Paper, Novel applications of nonwood cellulose for blood typing assays. Prof. Jasmina. Casals-Terré*1, Josep Farré-Lladós1, Allinson. Zuñiga1,2, Prof. Maria Blanca Roncero2, Prof Teresa Vidal2 1 Technical University of Catalonia, Mechanical Engineering Department, MicroTech Lab,Terrassa, Spain 2 Technical University of Catalonia, CELBIOTECH Paper Engineering Research Group, Terrassa, Spain * Corresponding Author: Address: MicroTech Laboratory, Department of Mechanical Engineering, Technical University of Catalonia, Terrassa 08222, Spain. E-mail. [email protected] Keywords: Sisal-based paper, Lab-on-a-Chip, sisal, paper-based microfluidics, blood typing test, Point-of-Care Testing (POCT). Abstract Paper-based microfluidics devices can create a new healthcare model. Cellulose is carbohydrate polymer biocompatible and hydrophilic. These characteristics enhance the development of user- friendly diagnostic devices, but the link between paper manufacturing process and performance of the devices is still unclear. Previous studies focused on either commercial papers or lab papers from wood-cellulose fibers, with different basis-weight. This work introduces the effect of refining process and lab paper from non-wood-cellulose fibers, focusing on sisal fibers to overcome the aforementioned challenge. Structural characteristics of paper, such as basis-weight and degree of refining, are optimized and correlated with blood typing test resolution. Unrefined sisal paper of 50 g/m2 and 100 g/m2 basis-weight exhibit a higher gray intensity level than refined paper, and also maximal capillary rise and a pore size suitable for blood grouping tests. Two different blood types were evaluated with results consistent with the traditional methods, testifying the usefulness of this methodology.
    [Show full text]
  • Nanofibrillated Cellulose Applied As Reinforcement for Short-Fiber Paper
    NANOFIBRILLATED CELLULOSE APPLIED AS REINFORCEMENT FOR SHORT-FIBER PAPER Daniele Cristina Potulski1*, Lívia Cássia Viana2, Ana Namikata da Fonte3 Mayara Elita Carneiro4, Graciela Ines Bolzon de Muniz5, Umberto Klock6 Universidade Federal do Paraná. Curitiba, Paraná, Brasil – [email protected]* ; [email protected] ; [email protected] ; [email protected] ; [email protected] 2 Universidade Federal do Tocantins. Gurupi, Tocantins, Brasil – e-mail: [email protected] Received for publication: 02/05/2018 - Accepted for publication: 31/10/2019 __________________________________________________________________________________________________ Resumo Nanocelulose aplicada como reforço para papel de fibra curta. Este trabalho teve como objetivo avaliar a influência da adição de diferentes porcentagens de celulose nanofibrilada sobre as propriedades mecânicas e físicas do papel feito a partir da polpa de fibras curtas. A celulose nanofibrilada foi obtida a partir de polpa Kraft de Eucalyptus sp. branqueada, submetida a três diferentes passes no moinho: 2, 10 e 20 passes. Os papéis foram produzidos com a adição de celulose nanofibrilada nas porcentagens de 3, 6 e 9%. Os resultados mostraram que a adição de celulose nanofibrilada aumentou as propriedades mecânicas: índice de tração, índice de arrebentamento e índice de rasgo. A porosidade e a densidade aparente diminuíram. A adição de 9% de celulose nanofibrilada, obtida a partir de 2 passes, proporcionou os melhores resultados com aumento da resistência à tração, arrebentamento e rasgo de 111, 114 e 70%, respectivamente, em comparação aos papéis normais. A melhoria das propriedades mecânicas do papel está relacionada à rede muito densa de ligações de hidrogênio, resultando em maior área de superfície obtida após a desfibrilação.
    [Show full text]
  • The Reference Measurements of the Paper Laboratory
    Saimaa University of Applied Sciences Technology Imatra Degree Programme in Paper Technology Petri Penttinen THE REFERENCE MEASUREMENTS OF THE PAPER LABORATORY Thesis 2012 ABSTRACT Petri Penttinen The Reference Measurements of the Paper Laboratory, 55 pages, 9 appen- dices Saimaa University of Applied Sciences, Imatra Unit of technology, Degree Programme in Paper Technology Bachelor’s Thesis 2012 Supervisor: Lecturer Esko Lahdenperä The purpose of this bachelor’s thesis was to create a basis for reference meas- urements of papers and boards used in the paper laboratory of Saimaa Univer- sity of Applied Sciences in Imatra. Testing was focused to the most common physical properties of paper and board. The aim for the reference measure- ments was to setup a database of product properties. This database is later used as reference material when new properties of other products are meas- ured. In the theory part of the work is introduced the laboratory environment, quality systems, and the physical properties of the papers and boards that are meas- ured. Also the test methods of these properties are explained. As the reliability of the testing is very important, in this work is also thought about the things that may cause uncertainty and errors to the results. In the experimental part of the work is performed the basic- and strength prop- erties of the specific papers and boards that were selected. The samples used consist of the paper and board grades manufactured in Stora Enso Imatra and M-real Simpele mills, and of the own samples made of birch, eucalyptus, pine and spruce pulps. These industrial manufactured paper and board types are commonly used with the student works and they can be found from the paper laboratory.
    [Show full text]
  • Relationship of Solid Ink Density and Dot Gain in Digital Printing
    International Journal of Engineering and Technical Research (IJETR) ISSN: 2321-0869, Volume-2, Issue-7, July 2014 Relationship of Solid Ink Density and Dot Gain in Digital Printing Vikas Jangra, Abhishek Saini, Anil Kundu gain while meeting density requirements. As discussed Abstract— Ours is the generation which is living in the age of above Dot gain is the measurement of the increase in tone science and technology. The latest scientific inventions have value from original file to the printed sheet. given rise to various technologies in every aspect of our life. Newer technologies have entered the field of printing also. II. MATERIALS AND METHODS Digital printing is one of these latest technologies which have further revolutionized entire modern printing industry in many Densitometer is used for measuring density of ink ways. It also facilitates working on large variety of surfaces, on the paper. Densitometer can be classified according to besides these factors digital printing have grown widely and type of materials they are designed to measure i.e. opaque made a special impact in print market. The presented analysis and transparent. Density of opaque materials is measured by system is used for study of print quality in Digital Printing. reflected light with a device called reflection type densitometer. Density of transparent materials is measured Index Terms— Digital Printing, Dot Gain, Solid ink density, by transmitted light with a device called transmission type Coated Paper and Uncoated Paper. densitometer. In order to measure the print quality i.e. solid ink density (SID) and dot gain (DG) on coated and uncoated I.
    [Show full text]
  • Dell™ C1760nw/C1660w Color Printer User's Guide
    Dell™ C1760nw/C1660w Color Printer User's Guide Regulatory Model: Dell C1760nw/Dell C1660w Contents Before Beginning . 11 A Notes, Cautions, and Warnings . 13 1 Dell™ C1760nw/C1660w Color Printer User's Guide . 15 Conventions. 15 2 Finding Information . 17 3 Product Features . 19 4 About the Printer . 21 Front View . 21 Rear View . 22 Space Requirements . 23 Operator Panel . 23 Securing the Printer . 24 Ordering Supplies . 25 Printer Setup . 27 5 Connecting Your Printer . 29 Connecting Printer to Computer or Network . 29 Direct Connection . 29 Wireless Connection . 30 Ethernet Connection (Dell C1760nw Color Printer only) . 34 Reconfiguring the Wireless Setting . 35 Template Last Updated - 2/7/2007 Contents 1 Turning On the Printer. 36 6 Setting Up Your Printer . 37 Setting Initial Settings on the Operator Panel (Dell™ C1660w Color Printer Only) . 37 Printer Setup Using the Software and Documentation Disc. 38 7 Setting the IP Address . 39 Assigning an IP Address . 39 The Operator Panel . 39 The Tool Box . 40 Verifying the IP Settings . 41 The Operator Panel . 41 The System Settings Report . 41 The Ping Command . 41 8 Loading Paper . 43 Loading Print Media in the Multipurpose Feeder (MPF) . 43 Loading Print Media in the Priority Sheet Inserter (PSI) (Dell C1760nw Color Printer only) . 48 9 Installing Printer Drivers on Computers Running ® Windows . 51 Identifying Printer Driver Pre-install Status . 51 Changing the firewall settings before installing your printer . 51 Direct Connection Setup . 51 For installing host-based printer driver . 51 For installing XML Paper Specification (XPS) printer driver . 52 Network Connection Setup . 54 Network Printer Setup on a Local Network .
    [Show full text]
  • Formability of Paper and Its Improvement N C O H I N S
    IENCE SC • VTT SCIENCE • T S E Formability of paper and its improvement N C O H I N S O I Paper and paperboard are the most utilized packaging materials in V Dissertation L • O S the world. This is due to such features as: renewability, G T 94 Y H • R biodegradability, recyclability,sustainability and unmatched G I E L S H printability. However, paper packaging is inferior to plastics in 94 E G A I R H C respect to moisture sensiivity, and limited ability to be converted H into advanced 3D shapes with added The ability of paper and paperboard to be formed into 3D shapes is described as formability, and in the fixed blank forming processes formability is governed by the extensibility of paper. The primary objective of this thesis is to improve the formability of Formability of paper and its improvement paper by increasing its extensibility. An additional objective is the characterization of formability as a mechanical property of paper and the development of a testing platform for the evaluation of formability. The formability (extensibility) of paper was improved using a set of methods which included: mechanical treatment of fibres, spraying of agar and gelatine, in-plane compaction of paper and unrestrained drying. Extensibility of paper was increased from 4% points (untreated fibres) to 15–18% points (mechanical treatment and addition of polymers), and up to 30% (in one direction) after compaction. This corresponds to tray-like shapes with a depth of 2–3 cm, depending on the curvature. Such values of formability are the highest reported so far in the scientific literature.
    [Show full text]
  • Cellulose-Based Electrical Insulation Materials Dielectric and Mechanical Properties REBECCA HOLLERTZ
    Cellulose-based electrical insulation materials Dielectric and mechanical properties REBECCA HOLLERTZ Doctoral thesis KTH Royal Institute of Technology School of Chemical Science and Engineering Department of Fibre and Polymer Technology ISBN 978-91-7729-327-9 TRITA – CHE-report 2017:21 ISSN 1654-1081 Tryck: US-AB, Stockholm, 2017 The following papers are reprinted with permission from: Paper I: Springer Papers II, III, VII and VIII: IEEE Transactions on Dielectric and Electrical Insulation AKADEMISK AVHANDLING Som med tillstånd av Kungliga Tekniska högskolan i Stockholm framläggs till offentlig granskning för avläggande av teknologie doktorsexamen fredagen den 12 maj 2017, kl. 10.00 i F3, Lindstedtsvägen 26, KTH, Stockholm. Avhandlingen försvaras på engelska. Fakultetsopponent: Professor Markus Biesalski, TU Darmstadt, Tyskland Copyright© Rebecca Hollertz, 2017 ABSTRACT The reliability of the generation and distribution of electricity is highly dependent on electrical insulation and is essential for the prosperity of our society and a ubiquitous part of our everyday life. The present study shows how some important material properties affect the electrical properties of cellulose-based electrical insulation systems which are used together with mineral oil in high-voltage transformers. Among other things, the effects of paper density and of the lignin content of the fibres on the dielectric response and charge transport of the papers have been studied. The underlying mechanisms of the inception and propagation of streamers, responsible for the most costly failures in transformers, at the oil-solid interface have been investigated and the important role of paper morphology on streamer propagation has been demonstrated. With papers, in contrast to films of synthetic polymers and microfibrillated cellulose, the branching of streamers increased and the length of slow negative streamers decreased.
    [Show full text]
  • Peer-Review Article
    PEER-REVIEWED ARTICLE bioresources.com IMPROVEMENT OF RECYCLED PAPER’S PROPERTIES FOR THE PRODUCTION OF BRAILLE PAPER BY IMPREGNATION WITH LOW GRADE CELLULOSE ACETATE: OPTIMIZATION USING RESPONSE SURFACE METHODOLOGY (RSM) Mei Chong Soo, Wan Rosli Wan Daud, and Cheu Peng Leh* Paper dust is a kind of cellulosic waste that is generated by converting operations in paper mills. It was derived to a low-grade cellulose acetate in this study. Papers made from recycled fiber were then impregnated with the resultant cellulose acetate. Effects of impregnation conditions on the paper properties were statistically investigated by employing central composite design (CCD) based response surface methodology (RSM). Four response variables, namely density, burst index, smoothness, and rate of surface wettability were analyzed. Polynomial estimation model of each response was developed as functions of three independent variables, which are pressing temperature (T), dipping time (D), and concentration of cellulose acetate (C). The paper which was impregnated based on the calculated optimum condition (T: 163 oC, D: 2.8 minutes, and C: 2.7 percent), possessed a density of 0.5450 g/cm3, rate of surface wettability of 0.012o/s, burst index of 2.84 kPa m2/g, and paper smoothness of 475 mL/min. There was no significant difference between the experimental values and the predicted values calculated from estimation models. The cellulose acetate impregnated Braille papers made from recycled fibre was found to have better properties than those of commercial Braille paper in terms of rate of surface wettability and burst index. Keywords: Braille paper; Cellulose acetate impregnation; Recycled paper; Response surface methodology Contact information: Bio-resource, Paper and Coating Divisions, School of Industrial Technology, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia * Corresponding author: [email protected] INTRODUCTION Cellulose acetate is a kind of thermoplastic, and it is one of the most important and widely used cellulose derivatives (Ibrahem et al.
    [Show full text]
  • The Effect of the Virgin Fibers to the Properties of Different Paper Products
    https://doi.org/10.24867/GRID-2020-p13 Original scientific paper THE EFFECT OF THE VIRGIN FIBERS TO THE PROPERTIES OF DIFFERENT PAPER PRODUCTS Tibor Czene 1 , László Koltai 2 1 Óbuda University, Doctoral School on Materials Sciences and Technologies, Budapest, Hungary 2 Óbuda University, Rejtő Sándor Faculty of Light Industry and Environmental Engineering, Budapest, Hungary Abstract: The products from paper are widely used materials with several benefits. The corrugated paper keeps items protected through long-distance logistic processes and constant shipping and handling. The corrugated boxboards are ideal options for any industry’s shipping, packaging and storage needs. Papers and cardboards are quite low cost and also provide environmental-friendly solutions, using recyclable materials such as used corrugated cartons and old newspapers. Recycling offers a reduction in environmental impact in densely populated regions and a large production of paper and board products. Generally, the use of recycled fiber produces paper with poorer mechanical properties due to the decrease in the interfiber bonding. The recycled pulp must be treated to restore its bonding strength, for which there are six methods possible: mechanical treatment, chemical additives, chemical treatment, fractionation, papermaking process modification and blending with virgin fiber. Although some mills produce 100% recycled paper, the majority augment their used pulp with some virgin fiber. Paper properties can be tailored within some ranges by modifying the properties of fibers, but the influence of fine quality on structure, strength and optical properties of paper can be even greater. The properties of papers are essentially determined by their raw materials. Most of these raw materials are made from 100% recycled fiber, but as the quality of the waste fiber varies, different chemicals must be used to provide the desired or expected properties.
    [Show full text]
  • Sampling and Testing Untreated Paper Used for Electrical Insulation1
    Designation: D 202 – 97 (2002)e1 An American National Standard Standard Test Methods for Sampling and Testing Untreated Paper Used for Electrical Insulation1 This standard is issued under the fixed designation D 202; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense. 1 e NOTE—Editorial changes made to footnotes 13-15, and Section 1 September 2002. 1. Scope synthetic, organic, or inorganic; fillers that are natural, syn- 1.1 These test methods cover procedures for sampling and thetic, organic, or inorganic; and flexible polymeric binder testing untreated paper to be used as an electrical insulator or materials. as a constituent of a composite material used for electrical 1.2 The procedures appear in the following sections: insulating purposes. ASTM or TAPPI Reference 1.1.1 Untreated papers are thin, fibrous sheets normally laid Procedure Sections (Modified) down from a water suspension of pulped fibers (usually Absorption (Rise of Water) 78 to 83 ... cellulosic), which may contain various amounts of nonfibrous Acidity-Alkalinity-pH 45 to 54 E 70 Air Resistance 98 to 101 D 726 ingredients, and which are calendared, if required, to obtain Aqueous Extract Conductivity 55 to 64 ... desired thickness and density. Nevertheless, these test methods Ash Content 40 to 44 D 586 are applicable, generally although not invariably, to papers Bursting Strength 102 to 107 D 774 Chlorides (Water-Extractable) 165 to 183 ..
    [Show full text]
  • Introduction to Stock Prep Refining Introduction to Stock Prep Refining 2016 Edition
    Introduction to Stock Prep Refining Introduction to Stock Prep Refining 2016 Edition Table of Contents Page 1. Introduction . 3 2. Trees, Wood and Fiber . 4 3. Pulping for Paper & Paperboard Manufacturing . 8 4. Structure of Paper & Role of Refining . 11 5. Pulp Quality Measurements . 14 6. Paper Quality Measurements . 17 7. Theory of Refining: i) Qualitative Analysis . 20 ii) Quantitative Analysis . 23 8. Refiner Plate Selection: i) Correct Amount of Refining (Specific Energy Input) . 25 ii) Correct Intensity of Refining (Specific Edge Load) . 27 9. Flow Considerations in a Stock Preparation Refiner . 30 10. Conclusion . 31 Appendix A – No load power in a stock prep refiner . 32 Appendix B – Flow considerations in a stock prep refiner . 34 Appendix C – Case study and sample calculations . 40 2 1. Introduction The purpose of this manual is to present an easy to understand description of the stock preparation refin- ing process. Useful methods for analyzing the process will be presented, together with guidelines for the proper selection of refiner fillings and operation of refiners. It is difficult to learn about pulp refining without first knowing something about the overall process of papermaking. This introductory manual will provide a very brief discussion of the process of converting trees into finished paper products. To include such a broad scope of information requires a certain degree of simplification. Nevertheless, the big picture is very helpful when considering pulp refining applications, identifying process problems and recognizing the real economic opportunities of an optimized system. The refining technologist must learn how to select refiner fillings and operate refiners so as to optimize the performance of the paper being produced using available raw materials.
    [Show full text]
  • Evaluation of Currency and Stamp Papers
    NBSIR 75-670 Evaluation of Currency and Stamp Papers E. L. Graminski and E. E. Toth Paper Evaluation Section Institute for Materials Research February 20, 1975 Progress report covering the period July 1 - December 31, 1974 Prepared for Bureau of Engraving and Printing U.S. Department of the Treasury Washington, D. C. 20401 NBSIR 75-670 EVALUATION OF CURRENCY AND STAMP PAPERS E. L. Graminski and E. E. Toth Paper Evaluation Section Institute for Materials Research February 20, 1975 Progress report covering the period July 1 - December 31, 1974 NOTE: This document has been prepared for the use of the Bureau of Engraving and Printing. Responsibility for its further use rests with that agency. Prepared for Bureau of Engraving and Printing U S . Department of the Treasury Washington, D.C. 20401 U. S. DEPARTMENT OF COMMERCE, Frederick B. Dent, Secretary NATIONAL BUREAU OF STANDARDS. Richard W. Roberts. Director CONTENTS Pa9 e 1. SUMMARY . ... ..... 1 1.1 Mechanical Refining, Wet Pressing, and Modification of Paper with Acrylic Resins . 1 1.2 Modification of Currency Paper 2 2. THE EFFECT OF MECHANICAL TREATMENT ON THE STIFFNESS RETENTION OF PAPER WHEN FLEXED ..... 3 2 . 1 Background 3 2 . 2 Experimental 3 2.3 Results and Discussion 5 2.3.1 The Importance of Apparent Density to the Retention of Stiffness with Flexing 6 2.3.2 The Relationship Between Paper Modulus and Paper Stiffness 7 2.4 Achievement of Maximum Density for Currency Paper 9 2.5 Analysis of the Modification of Currency r aper with Acrylic Resins 11 3. MODIFICATION OF CURRENCY PAPER WITH ACRYLIC RESINS BY THE SATURATION TECHNIQUE 13 3.1 Background 13 3.2 Experimental 13 3.3 Results and Discussion 14 4.
    [Show full text]