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The main aim of the present research is to examine the effect of progressive deinking and reprinting on the paper properties of inkjet-printed paper. A typical office copy paper was selected as the base paper and printed using an inkjet printer having at least 50 % ink coverage. Thereafter, it was deinked and reprinted thrice, and its paper properties were measured. The paper properties that were measured were roughness, porosity, opacity, brightness, specular gloss, whiteness, bursting strength, tearing resistance, tensile strength, contact angle, deinkability efficiency, visible dirt area, ink elimination factors, and color differences. The results showed that in comparison to the base paper, the progressively deinked and reprinted paper samples showed an increase in roughness, porosity, opacity, tearing resistance, dirt area, and color difference. On the other hand, there was a decrease in brightness, gloss, whiteness, burst strength, tensile strength, contact angle, deinkability efficiency, and ink elimination factors. The experiment shows that the progressively deinked and reprinted papers can be compared to the base paper in the major paper properties. [ABSTRACT FROM AUTHOR]

A novel paper multifunctional protective solution was prepared by mixing berberine modified trimethoprimed carboxymethyl cellulose (TMP-DCMC-BBR), KH-791 modified nano-SiO2 (KH791-SiO2) and hydroxypropyl starch phosphate (HPDSP), and the mechanical properties, optical properties, antibacterial properties, aging resistance, acid and alkali resistance of the paper coated with the protective solution were investigated. It is shown that the paper coated with the multifunctional protective liquid showed good mechanical properties, and has little influence on optical properties of the paper. At the same time, it had good antibacterial properties, aging resistance and acid and alkali corrosion resistance, and there is no obvious change in paper appearance, no decolorization and ink diffusion, which is in line with the principle of "repairing the old as the old and keeping the original appearance". Moreover, the compound solution has certain reversibility and can absorb a certain degree of ultraviolet rays, so as to weaken the damage of ultraviolet rays to the paper. It is an ideal multifunctional protective liquid for paper and has broad application prospects in paper protection. [ABSTRACT FROM AUTHOR]

A small framed display panel holds a selection of paper and media common in works on paper plus a set of Blue Wool Standards. The selection of materials and design of the panel including two types of glazing are presented, and the purpose of the panel as a tool for explaining the effects of light on materials is discussed. At the centre of the panel are watercolour samples prepared using primary colours in mixed washes that illustrate hue shift resulting from selective fading of one colourant. [ABSTRACT FROM AUTHOR]

The pulp and paper industry is increasingly seeking a sustainable and conscientious development, minimizing the environmental impacts caused by it. Therefore, reducing efficiently the number of stages used in the bleaching process can mean less consumption of water and chemical reagents, contributing to the reduction of harmful waste to the environment. Thus, this study sought to evaluate the pulp quality and some physical-mechanical properties (smoothness, tear and tensile indexes) of two new bleaching sequences A*DP and A*E*DP and compare them with the reference D0(E+P)D1P. To do so, industrial eucalyptus Kraft pulp pre-delignified with oxygen was used. The bleached pulp was refined to 1200, 1800 and 2400, in PFI mill and tested according to TAPPI standards to determine smoothness, tear and tensile indexes. Based on the results obtained, it was verified that the sequences studied are viable for using in bleaching plants, which allowed a reduction in the chlorine dioxide consumption and presented satisfactory smoothness, tear and tensile indexes for paper. [ABSTRACT FROM AUTHOR]

The ash condensation ability of the cigarette paper is an important factor affecting the cigarette grades. In this study, we put forward an effective method of improving this ability. Xanthan gum was successfully synthesized, applied as an ash integrator in the dip-coating process of cigarette paper production, and showed good performance. Cationic guar gum, cellulose phosphate and Hydroxyapatite (HAP) have been added in the pulp and showed better performance of the ash condensation property. The ash become much whiter and the scatter of the ash have been suppressed. Moreover, the further addition of HAP would result in a worse combustion efficiency, leading to the burning out of the cigarette in early time. [ABSTRACT FROM AUTHOR]

A novel macro-RAFT emulsifier was synthesized with S, S'-bis(α, α'-dimethyl-α"-acetic acid)-trithiocarbonate (BDATT), M13-10 (self-made emulsifier) and acrylate monomer, which was further used to prepare surface sizing agent. On the other hand, M13-10 was synthesized with iso-tridecanol polyoxyethylene ether, sodium methoxide and sulfamic acid as the starting materials. The hydrophilicity of macro-RAFT emulsifier and the performance of surface sizing agent were affected by BDATT used as the chain transfer agent and M13-10 as the hydrophilic monomer. So, the CMC and HLB of the emulsifier prepared with different M13-10 content and BDATT content, were compared, as well as the particle size of the prepared surface sizing agent, and the cobb, bursting resistance, tensile resistance, folding endurance and roughness of paper sized. The results reveal that surface sizing agent with macro-RAFT emulsifier of which the amount of M13-10 is 7 w% and the amount of BDATT is 2.5 w% demonstrates the best sizing effect on paper with the contact angle of 119°, the surface water absorption (cobb) of 48.8 g/m2, the bursting strength of 285 kPa, the folding endurance of 19 and the tensile strength of 59.6 kN/m. [ABSTRACT FROM AUTHOR]

This work has been conducted to investigate the effect of accelerated ageing on the filler-free (control) handsheets and the ones having Precipitated Calcium Carbonate (PCC) and Zeolite (Clinoptilolite) fillers. The diagnosis approach of this work has been based on the use of the techniques of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD). The FT-IR technique has allowed identifying the changes in cellulose components of handsheets. Likewise, the XRD technique has provided to diagnose the changes in crystallinity of the handsheets and fillers. The results found out that PCC and Zeolite fillers could be easily added to the structure of the paper network by changing various experimental variables. The loss of C−O functional groups and the formation of carbonyl groups in handsheets has been analysed by accelerated ageing. The spectroscopy results confirmed that usage of zeolite filler has a retarding and structurally improving effect on the glycosidic linkages. Recent findings have been provided new insights into the role of the synergistic effect of the combination of PCC and zeolite fillers in the decelerating of certain ageing mechanism. [ABSTRACT FROM AUTHOR]

The grey silverfish Ctenolepisma longicaudatum is a new and serious pest spreading rapidly across Europe. Compared to the silverfish Lepisma saccharinum, it does not depend on relative humidity above 70% and thrives also in new museum buildings, modern storage depositories, apartments, and office buildings. Especially collections of graphic art, modern art on paper, photographs, but also archives and libraries are increasingly affected by this pest. Damage of paper objects has been reported by different authors and institutions across Europe. As these animals live in inaccessible cracks and crevices inside the buildings, we investigated the spread of microorganisms on living grey silverfish, to show a potential additional threat posed by this pest. In 8 locations in Austria living animals were collected with traps and placed for 10 min on agar plates which were incubated for 2 weeks. After incubation of 50 agar plates, between 2 and 20 colonies of fungi were growing on each plate. The most dominant fungal genera were Cladosporium (Cladosporium cladosporioides clade) and Penicillium (Penicillium glabrum, Penicillium decumbens); also, species of the genera Aspergillus, Alternaria, Botrytis, Bartalinia, Byssochlamis, Chaetomium and Mycothypha were found. The diversity of fungi reflects the common fungal community of museums and archives. The spores and mycelial fragments of the fungi are obviously travelling on the legs and bodies of the silverfish. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers isolated from unbleached pulp are characterized by different surface properties due to presence of lignin at their surface, in addition to lower cost than isolated from bleached pulp. In the current work, the effect of cellulose nanofibers isolated from unbleached neutral sulfite and bleached soda rice straw pulps (so called UBCNF and BCNF) on improving paper sheet properties of unbleached and bleached rice straw pulp (so called UBP and BP) was studied. The effect on mechanical properties (tensile strength, burst strength, and tearing resistance) and physical properties (porosity and water vapor permeability) was studied. Scanning electron microscopy (SEM) was used to assist in explaining the obtained results. The result showed that using BCNF and BP resulted in better improvement in mechanical properties and also more effective in reducing porosity of paper sheets than in case of using UBCNF and UBP. These results indicated stronger bonding between nanofibers and pulps' fibers in case of using BCNF and BP (surfaces rich in cellulose hydroxyl groups) than in case of UBCNF and UBP (surfaces rich in lignin). Water vapor permeability of paper sheets made from unbleached or bleached pulps did not significantly affect by the addition the nanofibers. [ABSTRACT FROM AUTHOR]

The dimensional stability of paper products is a well-known problem, affecting multiple engineering applications. The macroscopic response of paper to moisture variations is governed by complex mechanisms originating in the material at all length-scales down to the fiber-level. Therefore, a recently-developed method, based on Global Digital Height Correlation of surface topographies is here exploited to measure the full-field hygro-expansion of single fibers, i. e. a surface strain tensor map over the full field of view is obtained as function of time. From the strain field, the longitudinal and transverse hygro-expansion and principle strains can be calculated. Long- and intermediate-duration dynamic tests are conducted on softwood and hardwood fibers. A large spread in the softwood fiber's transverse and longitudinal hygro-expansion coefficient ratio was found, while hardwood fibers behave more consistently. Computing the principle strain ratios reduces this spread, as it takes into account the variations of the deformation direction, which is directly affected by the micro-fibril angle (MFA). Furthermore, long-duration tests allow identification of the half-times at which the fibers equilibrate. Finally, the determined major strain angles for all fibers are consistent with the MFA ranges reported in the literature. [ABSTRACT FROM AUTHOR]

Paper has been the most significant carrier of written information for many centuries. To prolong the life expectancy of papers, the polyurethane based on nanosilica was used to strengthen the paper fibers in this work. The relation between the mass concentration of polyurethane based on nanosilica and the specific properties of papers (e. g., folding endurance, tensile strength, tearing strength, whiteness and glossiness) were investigated. In addition, the effect of polyurethane based on nanosilica on the acid/alkali resistance and ageing resistance were studied. The results showed that polyurethane based on nanosilica could significantly improve the mechanical properties and ageing resistance of papers. [ABSTRACT FROM AUTHOR]

This study examined the use of Plantago psyllium seed husk flour as paper additive with the aim of improving the properties of cellulose sheet. The husk flour was added in 5 wt%, 10 wt%, 20 wt% and 30 wt% to the cellulose suspensions and its effect on the handsheet properties was studied. The results showed that the direct addition of husk flour highly improves the mechanical properties of the handsheets like tensile index (with up to 400 %), burst index (with up to 600 %) and tear index (with up to 1200 %). Cobb and contact angle tests with distilled water showed that the handsheets containing husk flour are more hydrophobic compared to the unmodified handsheets. The Cobb-Unger and contact angle tests with oil revealed that the additive reduces the oil absorbency of the handsheets as well, at the highest by 86 %. Additionally, the water vapor and especially the air barrier properties were improved. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant capacity test showed that the modified handsheets had free radical scavenging properties. The direct addition of Plantago psyllium seed husk flour can be a promising, easy and green method to improve the mechanical and barrier properties, oil and water resistance of cellulose sheets. [ABSTRACT FROM AUTHOR]

The focus of this research is the stabilisation of paper with Verdigris, a green copper pigment. Due to its corrosive effects on paper, many important documents, paintings and maps are in danger. The efficiency of several commercially available deacidification agents on paper samples with Verdigris was tested, including magnesium-based Bookkeeper® dispersion, nano calcium hydroxide containing Nanorestore® and CaLoSiL® dispersions as well as a recently developed dispersion of nano calcium carbonate. The antioxidant tetrabutylammonium bromide was tested either alone or in combination with nano calcium based deacidification agents. The effect of the treatments was evaluated using colour, tensile strength, degree of polymerization and pH measurements. The results indicate that acidic degradation does not play a major role during accelerated degradation of paper containing Verdigris with moderately acidic pH value and that oxidative decay could be the main culprit of the decay. The method described, which involves the use of antioxidant tetrabutylammonium bromide in combination with calcium carbonate based deacidification dispersion, was proved to have a superior effect against degradation of paper with Verdigris in comparison to the treatments which involve deacidification agents only. Nano calcium hydroxide based deacidification agents result in high pH values of the paper samples and therefore cannot be advised for use on paper documents. [ABSTRACT FROM AUTHOR]

Coatings are generally applied for opacity, smoothness and gloss on the paper surface. Pigments such as CaCO3, Kaolin-Clay and Zeolite are used, and natural or synthetic binders are used. In this study, coatings using the CaCO3, Kaolin-Clay and Zeolite pigments on 80 gr/m2 high grade papers were made. PVOH was used as binder. Following coating, papers were processed through supercalendaring and printed with inkjet printer. Using INGEDE method 11p. recycling process printed papers were deinked. The optical properties of the recycled papers obtained after the deinking treatment, were compared with the unprinted papers. At the end of the study, the effect of coating on paper surface and the recycling performances of the inkjet printed papers were revealed. It was determined that the papers in which zeolite was used as a pigment were better, in terms of both surface properties and recycling performance when surface properties and recycling performance of coated papers were examined. When all the results were compared, it was found that the performances of coatings for which zeolite was used were much better than coatings such as CaCO3 and Kaolin-Clay, both in terms of surface coating properties such as opacity, roughness and gloss and recycling results such as brightness. [ABSTRACT FROM AUTHOR]

In conservation, the practical ability to implement treatment on objects of cultural heritage requires skills as an essential part of conservation expertise and constitutes an fundamental part of learning in conservation education. The acquisition of practical skills, which include cognitive and practical elements, is governed by laws that are primarily explained by means of organizational psychology and medicine where they have evolved in the form of step models. Stages of explicit and implicit knowledge are distinguished as well as factual-theoretical and practical-performative knowledge. Forms of learning are, in addition to guided learning, the experiment, the emergency, case studies and implicit forms of problem solving. The development of the expert can also be traced by the development of practical skills in five stages from beginner to expert. The stages of skills acquisition can be explained by reference to the European Qualifications Framework for Lifelong Learning (EQF) and the skill levels defined by the European Confederation of Conservator-Restorers' Organizations (E.C.C.O.). [ABSTRACT FROM AUTHOR]

The restorer Johann Michael von Hermann (1793–1855), famous in the early nineteenth century, has long fallen into oblivion. A recent discovery of his work associated with old master prints at the Staatliche Graphische Sammlung München has allowed a close study of his methods and skills as well as those of his pupil Ludwig Albert von Montmorillon (1794–1854), providing a fresh perspective on the early history of paper conservation. Von Hermann's method of facsimile inserts was praised by his contemporaries, before Max Schweidler (1885–1953) described these methods in 1938. The present article provides biographical notes on both nineteenth century restorers, gives examples of prints treated by them and adds a chapter of conservation history crediting them with a place in the history of the discipline. In summary, this offers a surprising insight on how works of art used to be almost untraceably restored by this team of Munich-based restorers more than 150 years before Schweidler. [ABSTRACT FROM AUTHOR]

Using disposable screen-printed electrodes is a convenient way of monitoring environmental pollution, production process control etc. Usually, commercially available screen-printed electrodes are used, but more and more studies are being carried out in the field of printing electrodes on thinner, low-cost and versatile substrates, including paper. In the present research, the comparison of screen-printed electrodes printed on different paper-based materials is presented. Two unique and innovative invasive plant-based papers made from (1) Japanese knotweed, (2) Canadian and Giant goldenrod and (3) commercially available cardboard were used as a printing material for the electrodes. The selected paper substrates were characterized, and screen-printed electrodes were printed. The influence of substrates' properties and pre- or post-treatment of the screen-printed electrodes on the electrochemical behaviour is thoroughly analyzed. The results indicate that the printing substrate (roughness) had the most significant influence on the cyclic voltammetry response. Comparing pre- and post-treatment of screen-printed electrodes, it was shown that grinding influenced the electrochemical activity significantly, while corona discharge does not have as significant influence. Besides, it was shown that the invasive plant-based papers are viable alternatives to commercially available papers and can be used as low-cost and eco-friendly alternatives for disposable screen-printed electrodes. [ABSTRACT FROM AUTHOR]

A composite filler was developed by pre-flocculation of fiber fines and precipitated calcium carbonate (PCC) particles with flocculants such as cationic polyacrylamide (cPAM) and bentonite. The composite filler was compared with a conventional loading method in terms of physical properties of handsheet and filler retention. The handsheets using the composite filler showed higher strength properties than that using a conventional loading at a similar paper ash content level, implying that paper ash content can be increased maintaining same level of paper strength. Optical properties such as opacity and brightness of the paper with the composite were quite similar with the paper with the conventional loading. Filler retention of the composite filler was slightly higher than that of the conventional loading even though retention aids were not used for the composite filler. Paper formation of the composite filler was better than the case of the conventional loading. However, the sheet with the composite filler showed lower bulk than that with the conventional loading. Conclusively, the composite filler technology by pre-flocculation of fines and filler has a potential to be utilized to produce a high loaded paper. [ABSTRACT FROM AUTHOR]

This study analyzed the effect that pulp fibers have on the surface softness component of hygiene paper. The surface softness component has more of an influence on the evaluation of subjective softness results than the bulk softness component. Using the surface softness measurement technique, this study aimed to evaluate the effect that fibers have on the softness of hygiene paper substrate via objective numerical values to measure the surface softness component of hand sheets composed of various pulp species. The results indicate that coarseness effects had the largest effect on softness among the various fiber characteristics, such as average fiber length, width and coarseness. As fiber coarseness increased, a rough surface formed, which resulted in an increase in the mean deviation from the average friction (MMD). Nonwood fibers had long fiber length and low coarseness, which enables the production of hygiene paper with high strength and softness. This study hopefully could lead to the development of various process technologies that may improve the softness of hygiene paper products. [ABSTRACT FROM AUTHOR]

In this study we have evaluated the suitability of laboratory testing methods to predict inkjet printing results. We have developed and used testing liquids that are spanning the operational window of industrial High Speed Inkjet (HSI) printers while still covering the maximum possible range of viscosity and surface tension. First we correlated liquid penetration measured with ultrasound (ULP) and direct absorption (ASA) to print through from HSI prints. The best correlation (R² É 0.7) was found for the sized paper. For papers with increasing liquid penetration speed we found a decreasing ability of both testing methods to predict print through, for the strong absorbing paper the correlation drops to R² É 0.2. Second we correlated contact angle and drop diameter to the dot area from HSI prints. Contact angle turned out to be a better predictor for printed dot area than drop diameter. Evaluating the change in contact angle over time we found the highest correlation to the dot area in the print when measuring the contact angle as soon as possible, in our case 1 ms after deposition of the drop on the paper. We also compared contact angle with microliter drops to picoliter drops, which are in the size scale of the actual inkjet droplet. To our great surprise correlations for microliter drops were equal or better than for picoliter drops, particularly for highly absorbing papers. Thus in order to predict dot spreading on paper our results suggest to measure the contact angle with microliter drops. Overall we found that, using laboratory testing methods, print through and dot spreading for HSI printing can be quite well predicted for slow absorbing papers but not very well for fast absorbing papers.

Surface characterization is important and has many applications in the paper industry. Surface characterization requires both surface roughness and surface friction. The relationship between the two has not been fully established for paper and paperboard. It has been a common practice that only the average property and the standard deviation with the coefficient of variation (COV) are reported for surface roughness and friction measurements. This practice, however, provides few information on surface structure and can lead to wrong judgments because two samples having the same average and the COV can have different physical properties. To avoid such mistake, a new surface characterization method has been developed. To this end, surface roughness- and frictionprofiles have been obtained using a latest version of Kawabata surface tester (Model: KES-SESRU, Kato Tech, Kyoto Japan). This new version uses the same stylus for both measuring surface roughness and friction under the same operating conditions. It was found that a correlation between the surface roughness and surface friction was very low. This indicates that they should be independent of each other. Therefore, both should be determined for surface characterization.

In conservation, the practical ability to implement treatment on objects of cultural heritage requires skills as an essential part of conservation expertise and constitutes an fundamental part of learning in conservation education. The acquisition of practical skills, which include cognitive and practical elements, is governed by laws that are primarily explained by means of organizational psychology and medicine where they have evolved in the form of step models. Stages of explicit and implicit knowledge are distinguished as well as factual-theoretical and practical-performative knowledge. Forms of learning are, in addition to guided learning, the experiment, the emergency, case studies and implicit forms of problem solving. The development of the expert can also be traced by the development of practical skills in five stages from beginner to expert. The stages of skills acquisition can be explained by reference to the European Qualifications Framework for Lifelong Learning (EQF) and the skill levels defined by the European Confederation of Conservator-Restorers' Organizations (E.C.C.O.). [ABSTRACT FROM AUTHOR]

The restorer Johann Michael von Hermann (1793–1855), famous in the early nineteenth century, has long fallen into oblivion. A recent discovery of his work associated with old master prints at the Staatliche Graphische Sammlung München has allowed a close study of his methods and skills as well as those of his pupil Ludwig Albert von Montmorillon (1794–1854), providing a fresh perspective on the early history of paper conservation. Von Hermann's method of facsimile inserts was praised by his contemporaries, before Max Schweidler (1885–1953) described these methods in 1938. The present article provides biographical notes on both nineteenth century restorers, gives examples of prints treated by them and adds a chapter of conservation history crediting them with a place in the history of the discipline. In summary, this offers a surprising insight on how works of art used to be almost untraceably restored by this team of Munich-based restorers more than 150 years before Schweidler. [ABSTRACT FROM AUTHOR]

The growth of oyster mushroom (Pleurotus ostreatus) on pulp and paper industry wastes was studied. Specifically, the question was investigated whether solid-state fermentation of P. ostreatus on paper-mill deinking sludge and primary sludge substrates is appropriate for production of enzymes, relevant to the pulp and paper industry. Following fermentation, extracellular protein was extracted and the specific activities of four enzymes were determined, namely, the cellulase, xylanase, lipase and peroxidase. Furthermore, the effects of the pH of the extraction buffer on these enzyme activities were determined, along with the effects of the incubation time. The data show that P. ostreatus can grow on solid wastes from the pulp and paper industry, which could help to minimize the waste volume and to decrease the ecological impact. Furthermore, the solid wastes in focus are good substrates for the production of commercially interesting enzymes. [ABSTRACT FROM AUTHOR]

Paper documents with severe iron gall ink corrosion are difficult to handle. While a defined treatment for the chemical stabilisation exists already, methods to improve the mechanical stabilisation have yet to be developed. The degradation of the selected objects was so advanced that the documents needed special attention concerning handling and mechanical re-enforcement. After a calciumphytate-calciumhydrogen treatment, documents were lined with light weight Japanese paper and gelatine. A workflow for treating severely degraded iron gall ink documents was developed. Since the removal of objects from the silk screen frames after the wet treatment proved to be too difficult, a PE-board was introduced as an alternative washing support. Most synthetic fleeces such as Hollytex or Paraprint adhere to its granulated surface by mechanical means. This makes PE-board a practical support during any wet treatment of paper-based objects. [ABSTRACT FROM AUTHOR]

The attractive structural and mechanical properties of cellulose substrates (paper, cloth, and thread), including passive fluid transport, biocompatibility, durability, and flexibility, have attracted researchers in the past few decades to explore them as alternative microfluidic platforms. The incorporation of electrochemical (EC) sensing broadened their use for applications such as clinical diagnosis, pharmaceutical chemical analyses, food quality, and environmental monitoring. This article provides a review on the microfluidic devices constructed on paper, cloth, and thread substrates. It begins with an overview on paper-based microfluidic devices, followed by an in-depth review on the various applications of EC detection incorporated on paper-based microfluidic devices reported to date. The review on paper-based microfluidic devices attempts to convey a few perspective directions that cloth- and thread-based microfluidic devices may take in its development. Finally, the research efforts on the development and evaluation, as well as current limitations of cloth- and thread-based microfluidic devices are discussed. Microfluidic devices constructed on paper, cloth, and thread substrates are still at an early development stage (prototype) requiring several improvements in terms of fabrication, analytical techniques, and performance to become mature platforms that can be adapted and commercialized as real world products. However, they hold a promising potential as wearable devices. [ABSTRACT FROM AUTHOR]

The Cyrillic books Menology for May (1705), The Bible (1822) and Mirror (1816) were consigned for conservation to the Conservation Laboratory at the National Library in Skopje. The first two books were printed in Moscow, while the third book was issued in Vienna, although it originates from the territory of the former Ottoman Empire, present-day Republic of Macedonia. In order to design a conservation protocol, papers and inks used in the books were characterized and their condition was assessed. Micro-chemical tests were used in order to identify the type of paper fibres and materials added to the paper pulp. FTIR was applied to confirm the findings for the sizing and fillers found in the paper support. Inorganic pigments were analysed by micro-Raman spectroscopy. The original paper in the Russian books was made of rags with less than 5% lignin content present, whereas the paper in Mirror was made of raw and unbleached hardwood. Distinct types of sizing have been identified: gelatine/alum in Menology for May and Mirror and gelatine/rosin in The Bible. The pigments identified are lamp black, vermilion, Prussian blue and calcite. The study elucidates which internal and external factors could cause further decay of the books and will help in making informed decisions concerning the further preservation of the objects. [ABSTRACT FROM AUTHOR]

Silver-clay nanohybrids based on silver nanoparticles (AgNPs) with montmorillonit (MMT) and milled MMT, shortly AgMMTnano and AgMMTmilled, have been prepared to improve the performance of antibacterial properties of paper. The results obtained by dynamic light scattering indicated the presence of silver particles in the nanometer range, which have a great accumulation tendency. The results of AAS and ICP-AES tests showed that nanosilver amount in the AgMMTmilled was doubled compared to the AgMMTnano, but according to the EDX results, the amount of nanosilver in paper treated with the former was less than in the latter. FE-SEM images showed that the dimensions of deposited nanosilver on the surface of clay were smaller than in case of AgNPs alone. Papers treated with nanohybrids had better antibacterial properties compared to that prepared by naked nanosilver. It was also found that the antibacterial property of papers treated with AgMMTnano were more stable during three-stage tests compared to those with AgMMTmilled. Nanohybrids with Ag conc. more than 15 ppm, especially hybrids with Ag conc. of 50 ppm, result in a significant improvement in antibacterial properties of paper. It can be concluded that silver-clay nanohybrid with a 25-ppm concentration of nanosilver could be the best and most economic antibacterial component. [ABSTRACT FROM AUTHOR]

Electron Paramagnetic Resonance (EPR) is a technique devoted to the identification and characterization of paramagnetic species, i.e. chemical species with unpaired electrons. Very common paramagnetic species which can be detected through EPR in historic paper are Fe(III), Mn(II), Cu(II) ions and radicals, where Fe(III), Cu(II) and radicals play a relevant role in paper degradation. Specifically, Fe(III) is almost ubiquitous in historic paper. Here we propose an overview of the EPR signals in historic and artificially aged paper, and in particular, we would like to show how a deep analysis of EPR signals from paper could provide useful information about the paper's origin and unique indications of the degradation and oxidation level of the paper. [ABSTRACT FROM AUTHOR]

Reconstituted parchment is, besides Japanese paper and parchment, a feasible and widely used material for filling in losses in parchment. This study investigates changes in haptic and visual qualities of the material caused by modifications with different ingredients like paper and parchment fibres. Additionally, selected procedures processing parchment to parchment powder were examined. As a brief introduction, the paper gives an overview over the existing types of reconstituted parchment that are used traditionally in parchment conservation. In addition it attempts to clarify the terminology for this material. Parchment powder was produced with simple and readily available equipment, by different methods: sanding, grating, grinding, shredding, milling and ice-crushing. The different types of home-made powder were compared to a pre-fabricated parchment powder obtained from a parchment maker. The test series showed that the type of preparation of parchment powder influences the fibre texture which in turn affects the material's properties visually and haptically. While all methods are clearly more time-consuming than buying ready-touse material, some preparations, e.g. grating, shredding and ice-crushing, showed superior properties. [ABSTRACT FROM AUTHOR]

The in-plane shear strengths (IPSS) of copy paper, filter paper, and sack paper were obtained from an asymmetric four-point bending (AFPB) test. Rectangular tabs of medium-density fibreboard (MDF) were bonded to the paper specimen. The length of the clearance between the tabs was varied, and the influence of the clearance on the IPSS value was investigated. The IPSS obtained from the AFPB test was compared with that obtained from a 35° off-axis tension (OAT) test, which was proposed in a previous study. The IPSS values obtained from the AFPB tests on the copy paper and sack paper were significantly lower than those obtained from the 35° OAT tests because of the localised buckling caused by the negative principal stress. In contrast, the IPSS values obtained from the AFPB and OAT tests on the filter paper were in agreement when the clearance length was >5 mm because the buckling effect was excluded. [ABSTRACT FROM AUTHOR]

This paper establishes mixed multiplicity formulas concerning the relationship between mixed multiplicities of modules and mixed multiplicities of rings via rank of modules. [ABSTRACT FROM AUTHOR]

The off-axis tensile strength (OATS) of copy paper, filter paper, and sack paper was obtained from dog-bone specimens. The relationship between OATS and the off-axis angle (OAA) was predicted under several failure conditions. Additionally, the shear strengths (SS) of these papers were evaluated based on the results of OAT tests. The OATS could be accurately predicted under several Hill-type failure conditions. An equation for deriving the in-plane SS of these papers was proposed based on the tensile strength of the specimen with a 35° OAA, in which the contribution of the shear stress component was maximum. [ABSTRACT FROM AUTHOR]

Paper diagnostics are devices made of paper and cellulosic materials to recognize and quantify biomolecules and chemical agents affecting health. There has been a rapid increase in interest for paper-based diagnostic methods in recent years. This is because paper is cheap, widely available, easily engineered, biodegradable, combustible, biocompatible, sterilizable, hydrophilic, and easy to functionalize and process into diagnostic devices. Paper is a very attractive substrate to develop as a low-cost diagnostic platform. Paper can serve four functions in a diagnostic: 1) transport and measurement of sample and analytes, 2) reaction support, 3) separation of reactants from products, and 4) communication of results. When an aqueous analyte, such as blood, saliva, urine or feces is tested using a paper diagnostics analytical device (PAD), the fluid is driven by capillary flow induced by the porous and hydrophilic structure of the cellulose fibers, causing wicking through the paper inter-fiber space. Should hydrophobic barriers be formed onto or within paper, microfluidic systems can be created, allowing for the passive transport of the analyte. This article has four sections. The first presents paper as a composite and highlights its properties and attributes with respect to modern paper diagnostics needs. Functional printing is presented as a technology to manufacture paper diagnostics. The second section analyzes paper diagnostic design. PADs based on one dimension (1D), 2D and 3D flow, the methods of reporting, and the principles of detection are reviewed. The third section investigates applications in health and medicine for paper diagnostics in terms of clinical diagnostics, physiological disorders, and pathogenic diseases. The last section presents an analytical perspective of some of the critical issues. It is the objective of this article to analyze paper as a viable technology for producing low-cost medical analysis and to delimit the range of applications and potential best suited to paper diagnostics. [ABSTRACT FROM AUTHOR]

The article presents a case study on the treatment of an etching that had been bleached in the past with 4% hydrogen peroxide and had suffered colour reversion in the form of foxing and discolouration. It states that staining could have been caused by the action of hydrogen peroxide on iron particles in the paper. The extensive rinsing treatment reportedly diminished the foxing stains.

The article discusses the development of high intensity discharge (HID) lamps application for light bleaching art works on paper. It describes the construction of a light bleaching unit using HID lamps, and cites key functionalities of the system. It discusses methods of bleaching for their principal working parameters including immersion bleaching, bleaching on the slant washing board, and on a moist blotter.

Paper material produced after about 1850 contains additives that cause progressive acidification of the cellulose matrix, which can result in severe degradation of the material and simultaneous deterioration in its strength properties. This problem has affected whole stocks of libraries and archives, in response to which the process of 'mass deacidification' has been developed. In this study, the structure and chemistry of the active reagent used in the main variant of this process has been identified as magnesium n-propoxycarbonate. The reagent, introduced in an inert fluorinated solvent, neutralizes acids in the paper matrix and simultaneously deposits a reserve of alkaline magnesium salts that counteract re-acidification. At the same time, it is much less alkaline than the magnesium alcoholates so that alkali-induced degradation reactions of cellulose (β-alkoxy elimination) are avoided. [ABSTRACT FROM AUTHOR]

Mixtures of stickies-containing and stickies-free pulps were investigated for their deposition potential in an attempt to better understand the interactions of dissolved and colloidal material (DCM) when mixing two different pulps. The filtered pulp mixtures were tested in a deposition apparatus which measures both the dynamic fluid as well as impact deposition by an established optical scanning method. A pulp filtrate of model stickies led to deposition according to the proportion of stickies-containing pulp in the mixture. Other mixtures of pulps, however, led to deposition that differed from the predicted value. It is theorised that pulp fibres present in the mixture could adsorb the polysaccharides that would otherwise keep the colloidal system electrostatically stable. This destabilisation was most prominent at lower proportions of the stickies-free pulp suspensions used for mixing. These results show that care must be taken when mixing different pulps for paper and board production, as even a small amount of replacement pulp can lead to destabilisation of DCM and formation of deposits. Furthermore, special care must be taken when mixtures of pulps are used to validate stickies measurements. [ABSTRACT FROM AUTHOR]

The activation parameter developed is based on the fiber wall thickness distribution, fiber curl distribution, and water retention value of the unrefined fibers. The mechanical properties of paper that contain chemical pulp depend, among other things, on the free fiber segment activation between fiber-fiber crossings that is created during drying. Experimental data revealed that the degree of fiber swelling is responsible together with the fiber shape factor (curl) and fiber wall thickness for the extent of fiber network activation. The amount of bonding between fibers also affects fiber segment activation. Based on the experimental data, it was deduced that interfiber bonding ability of fibers, characterized as the water retention value, was mainly responsible for the development of handsheet density. Tensile index development was more affected by the morphology of fibers, which was the main determinant for high activation potential of fibers. Factor analysis was used to identify the main causes of variation for a refining data set of 20 Eucalyptus grandis samples. Three independent descriptors were found to be responsible for the majority of the variation: the bonding and activation factor, the factor of microcompressions, and the factor of fiber wall thickness and fiber curl. The activation parameter developed in this study can be used to determine the effect of fiber segment activation and inter-fiber bonding on the inplane mechanical properties of paper. [ABSTRACT FROM AUTHOR]

Ozone bleaching is a common practice in pulping, and also of eucalyptus, where it is usually applied in combination with bleaching sequences based on oxygen, hydrogen peroxide, or chlorine dioxide. Ozone has been proven to be a highly efficient and competitive bleaching chemical in terms of delignification efficiency, low costs, and reducing ecological impact. The objective of the present work was to evaluate technology with ozone/alkaline extraction (Z/E) and ozone/chlorine dioxide (Z/D) for bleaching of eucalyptus kraft pulp. Primarily, the impact of these bleaching steps on refinability and quality of pulp should be investigated. As reference, the sequence D*(EP)D (hot chlorine dioxide, extraction in presence of hydrogen peroxide, chlorine dioxide) was selected, which is considered as the state-of-the-art bleaching in elemental chlorine free (ECF) bleaching technology. Various bleaching sequences with ozone in their first step (Z/D(EP)DP, Z/D(EP)DD, Z/EDP, Z/EDD and A*Z/EDP) were found to provide kraft pulps of similar brightness and in similar yield as the reference sequence D*(EP)D. The kappa number, viscosity, and the contents of glucose and xylose, and hexenuronic acid of the pulps were also similar. In addition, the Z sequences resulted in a substantial reduction of the total chlorine dioxide consumption (more than 30.3% in all cases). The A*Z/EDP sequence, which proved to be the most efficient, yielded 87.5% ClO2 reduction. The studied bleaching sequences also resulted in substantially improved brightness reversal with regard to the reference sequence. The sequence A*Z/EDP was also the most efficient as regards the removal or organochlorines (OX) from the pulp and their reduction in the effluents (AOX). Ozone bleaching sequences improved paper strength, especially with the A*Z/EDP sequence. [ABSTRACT FROM AUTHOR]

The article presents a study on the viability of using aqueous solutions of sodium percarbonate as a new method for bleaching discolored paper. Appositely prepared oxidized papers and authentic discolored papers were analyzed to examine the advantages and drawbacks of sodium percarbonate treatments. Results suggest that sodium percarbonate solutions can be a valid substitute to hydrogen peroxide solutions in brightening discolored mechanical pulp papers because it is more stable when stored, safe to use and has low environmental impact.

The article examines the impact of two humidification and flattening methods for albumen prints on the surface characteristics of the albumen. The two methods include a Gore-Tex® sandwich and the use of a humidity chamber. For humidification process, variables include the length of time and levels of relative humidity and the parameters measured include the changes in number and/or size of the cracks. It was found that a 10-minute exposure to the Gore-Tex® sandwich method resulted to a significant change to the cracks. Meanwhile, in humidity chamber, there is no change in cracks even after 24 hours. After evaluating several flattening methods after humidification, it was found that the "hard-soft sandwich" developed by Homburger and Korbel is the most effective.

AbstractThe aim of the present study was to determine the effect of a variety of abnormal fibres on the mechanical properties of paper made from Norway spruce, Picea abies(L.) Karst. Fibres representing abnormality were obtained from trees treated by irrigation and fertilisation. Moreover, fibres from compression wood and its accompanying opposite wood were isolated. The effect of dislocations on paper quality was studied on four mixtures (20, 40, 60 and 80% fibres with induced dislocations) of untreated/compressed fibres. Two more groups consisting of control untreated samples and samples with 100%-induced dislocations were also included in the test. The mechanical properties of the paper were tested and the results were compared to those of control samples. Abnormal fibres reduced the desired mechanical properties of the final paper concerning tensile strength, modulus of elasticity and tear-tensile index. Irrespective of the type of treatment, all morphological changes introduced in fibre cell walls appear to directly affect changes in the mechanical properties of the paper. Control samples had a tear index of 25 compared to 10 mN m2g-1of samples containing 100% dislocations. It is obvious that 20% of dislocations, an amount that is expected to be induced in pulp under mechanical processing and transport, will contribute to a decrease in tear index with an average of 3 mN m2g-1, i.e., 10% of the total value. [ABSTRACT FROM AUTHOR]

AbstractSamples of two historical papers from the late 17th and early 18th centuries were irradiated with a 350-nm ?maxlight source. Atomic force microscopy examination of untreated samples of these laid paper sheets revealed notable surface inhomogeneity. Diffuse brightness values show that irradiation resulted in an initial decrease followed by a rapid increase in brightness with increasing irradiation time from 0.5 to 28 h. The bleaching effect then slowed, following a logarithmic path that did not plateau within 197 h of irradiation time. Irradiated sheets stored for 3 months exhibited brightness reversion of 7%. Fluorescence also decreased with irradiation time if excitation wavelengths of 320, 350, and 400 nm were applied for samples exposed to narrow-band irradiation at 350 nm. The fold endurance decreased by 34–72% after 197 h of irradiation. Changes in tear and tensile values were less dramatic. The Z-direction ultrasonic velocity decreased after 197 h of irradiation; however, the ultrasonic conductivity partially recovered during 9 months of storage. [ABSTRACT FROM AUTHOR]

The article presents a study for the assessment of how much of the cellulose ether used by conservators can actually be dissolved from paper samples. Cellulose ethers used in the study included ethylcellulose, methylcellulose and hydroxyl propyl methylcellulose supplied by Dow Chemical Co. Quality writing paper were used for preparing paper samples.

The article discusses the theoretical and practical principles of the methodology and the criteria used for the evaluation of paper conservation treatments. A method for the accelerated aging of the samples is employed in most of the cases to demonstrate the future effects of the intervention. The most popular method from the mechanical properties is folding endurance, while from the chemical properties is pH. Colorimetry contributes to the evaluation process.

The article provides insights into the kinetics of paper degradation. The most important parameter to evaluate the degradation of paper is the number of scissions, which can be estimated by the degree of polymerization. The presence of potential degradation sites should always be verified by comparing the value of the viscometric degree of polymerization before and after reduction.

The wide-line 1H nuclear magnetic resonance (NMR) spectrum of paper in equilibrium with ambient humidity consists of super-imposed relatively broad and narrow lines. The narrower line is of the order of 2 kHz wide at half the maximum height, while the broader line is of the order of 40 kHz in width at half height. On the basis of these line widths, the narrow line is assigned to water sorbed to the paper, and the broad line to the polymeric constituents of the paper. It was not possible to distinguish between the various polymeric components of paper contributing to the 1H NMR spectra. A modified Goldman-Shen pulse sequence was used to generate a spatial magnetisation gradient between the polymer and water phases. The exchange of magnetisation between protons associated with water and those associated with the macromolecules in paper was observed. The exchange of magnetisation is discussed within a heat transfer model for homonuclear dipolar coupling, with exchange being characterised by a spin-diffusion coefficient. Consideration of the magnitude of the initial rate of the exchange process and estimates of the spin-spin relaxation times based on 1H line widths indicate that some water must exist in a sufficiently immobile state as to allow homonuclear dipolar interactions between adjacent polymer and water protons. Thus, water sorbed onto paper must exist in at least two states in mass exchange with each other. This observation allows certain conclusions to be drawn about the ratio of free/bound water as a function of moisture content and the dispersal of water within the polymer matrix. [ABSTRACT FROM AUTHOR]