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Paperboard boxes represent a sought-after class of packaging products, where the use of recycled fibers offers a cost-effective and environmentally friendly alternative to virgin fibers. The presence of a significant proportion of recycled fibers in the paperboard leads to a number of limitations associated with the deterioration of its characteristics. In this study, the properties of coated and uncoated paperboards containing recycled fibers, wood pulp, and virgin cellulose fibers were investigated using a laboratory sample of paperboard produced from 100% recycled fibers without any chemical additives for comparison. Properties such as smoothness, bulk density, absorbency, and tensile strength, as well as colorimetric characteristics, were determined for the recycled paperboards; for the latter test, charts were printed using inkjet printing and UV-curable inks. Whiteness was calculated by three formulae (CIE, Berger, and Stensby), and all the paperboards had a relatively low whiteness (not exceeding 90 CIE), with a yellowish tint due to recycled fibers and mechanical pulp in the composition. The absence of optical brightening agents in the paperboards was experimentally confirmed. The color gamuts of the paperboards were in direct ratio to their whiteness, with the highest ones demonstrated by the coated paperboards. Color reproduction, according to the tone value increase curves, also depended on the whiteness. Uncoated paperboards demonstrated smaller color shifts than the coated ones, with the greatest increase in tone for yellow color. Coated recycled paperboards are suitable for packaging printing under the same conditions as virgin fiber boards, while uncoated boards are the recommended choice for digital printing with UV inks. [ABSTRACT FROM AUTHOR]

Purpose – This paper aims to investigate the effect of paper properties (whiteness, gloss and roughness) on colour laser printing quality. Paper characteristics have a significant influence on print quality and are crucial variables for predicting and reproducing colour. Design/methodology/approach – Six kinds of paper with different properties were selected and the effects of the paper characteristics on the printed paper were studied. Samples were printed with cyan, magenta and yellow toner with a laser printer under identical conditions. The papers and printed papers were evaluated with atomic force microscope, scanning electron microscope, gloss-meter, spectrophotometer and densitometer. Findings – Results showed that print quality is statistically dependent on paper type, and the average optical density of printed paper varied for different papers. Furthermore, the increase in the roughness and gloss of the papers in comparison to whiteness more significantly affected the optical density of paper by reducing it. Practical implications – To achieve high-quality print, laser printing paper and toner require controlled characteristics. Originality/value – For the first time, the present study evaluated the influence of paper properties on the quality of colour laser printing. [ABSTRACT FROM AUTHOR]

Calcium carbonate (CaCO3) is an essential mineral critical for various applications in many industries like plastic, rubber, paint, and paper manufacturing. However, salable CaCO3 products need to meet specific requirements. For the paint and paper manufacturing industries, the whiteness index (WI) of CaCO3 is an important property because it strongly influences the final color of paper and paint products. In this study, the effects of retention time and pulp density on the WI after attrition-scrubbing of calcite tailings were investigated. To increase the whiteness index, an attrition scrubber was used to remove impurities on the CaCO3 surface with different pulp densities—40, 45, 50, 55, 60, and 70% solids—and retention time—10, 15, 20, and 25 min—as process variables. The results of laboratory-scale experiments found that the attrition-scrubbing process improved the whiteness index of CaCO3 tailings and reduced its iron content. The optimum condition was at the pulp density of 55% solids, which was used in the pilot-scale experiments. The results of the pilot-scale tests were consistent with the laboratory-scale, indicating that the attrition-scrubbing process can be used to improve the quality of CaCO3 tailings. [ABSTRACT FROM AUTHOR]

This review article highlights progress in understanding the optical properties of paper. Paper’s appearance can be defined in terms of its opacity, brightness, color, fluorescent properties, gloss, and various quantities related to its uniformity. The phenomena that give rise to paper’s optical properties, especially its ability to scatter and absorb visible light, are highly dependent on paper’s structure and its chemical composition. In an effort to engineer low-cost products having relative high opacity and brightness, it is necessary to optimize the material selection and processing conditions. The dimensions of solid materials and void structures within the paper are key factors for optimizing the optical properties. In addition, additives including bleaching agents, mineral particles, dyes, and fluorescent whitening agents can impact paper’s optical properties Paper’s appearance depends, in subtle ways, on the processes of its manufacture.

Paper properties, including the chemical or optical characteristics influence the quality and colorimetric characteristics of final printed colors. In this study, the effect of gloss, texture, and whiteness of the paper on the printed colors were investigated. The study was applied on 10 coated papers with different texture, gloss or whiteness, and the same grammage using two inkjet printers. It was found that the reproducibility of the printer can be affected with the paper brand, and this effect is statistically dependent on the brand of printer. The kind of paper significantly influences the light fastness of the final printed colors, and this effect statistically depends on the printer. Although, the paper's properties such as gloss and whiteness affect the gamut volume, it is not totally possible to model this effect. The effect of paper on the colorimetric values of the final printed colors is statistically significant. However, the influence of the brand of printer on the color changes via the paper difference is not statistically provable. Edge frequency technique was introduced as an appropriate method for computing texture properties of papers. The texture difference computed by this method shows a suitable correlation with the color differences caused by changing the paper's texture; however, it depends on the printer's brand. Furthermore, there is a good correlation between the Edge frequency difference and the gamut volume variation for papers with different texture while the other parameters such as gloss and whiteness are the same. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 284-291, 2013 [ABSTRACT FROM AUTHOR]

In order to improve the whiteness of fly ash, the particles were coated by in-situ precipitation of calcium carbonate. After different mass ratios of calcium oxide to fly ash were mixed into water, a certain amount of carbon dioxide was bubbled into the mixture to form a precipitated calcium carbonate deposit on the surface of fly ash. With the help of scanning electron microscopy (SEM), the process and the coating mechanism of the unmodified and modified fly ash were studied. The results showed that when a 1:1 mass ratio of calcium oxide to fly ash was implemented, the whiteness of fly ash was increased from 30.3 (the original fly ash) to 74.0 (the modified fly ash). After appropriately controlling for the rate of carbon dioxide, the whiteness was improved to meet the standard for filler in the papermaking industry, and also great advantages in paper physical strength were demonstrated.

The efficiency of optical brightening agents (OBAs), also known as fluorescent whitening agents (FWAs), has long been of interest in the production of uncoated fine paper, particularly in uncoated fine paper grades containing high-yield pulp (HYP). The increasing levels of whiteness and also the increasing HYP substitution in fine papers has made OBA efficiency an important issue. This paper summarizes recent research findings in understanding and enhancing OBA efficiency in fine papers containing HYP, with focus on the main factors affecting OBA efficiency in both wet end and size press application. These factors include the base sheet brightness and whiteness of the pulp, UV competitors, OBA retention, quenching effects, and OBA migration at the size press. Some new technologies to improve OBA efficiency are discussed. [ABSTRACT FROM AUTHOR]

The optical properties of pigments used for paper coating are linked to their morphology. The light scattering through coated layers depends upon the size and the size distribution of the pigments and their packing behavior. In this report the effect of particle packing of various calcium carbonate pigments on the whiteness of the final coated paper is studied. Different grades of calcium carbonate pigments of different particle size distribution and optics were used for coating applications on base papers. Base papers of different optics were also selected. The entire study was carried out at different coat weights. It was observed that the overall scattering from the coated sheet depends upon the light scattering from the base paper as well as through the coated layer. Higher light scattering through the coated layer will lower the effect of the base paper, whether it is dark or bright. So high bright and white pigments are not only the criteria for an enhancement in the optical properties of coated paper; the particle size and size distribution should also be considered before introducing any pigment into a coating formulation. The base optics should also be chosen on the bases of the pigments' optics and their morphology. [ABSTRACT FROM AUTHOR]

It becomes apparent that Preeti's only connection to her Indian roots is the convenient fact she speaks Hindi (a production necessity perhaps, given the film's national audience) and demonstrates complete ignorance towards any of the spiritual, historical or scriptural learning Bharat is keen to instil. Recalling Preeti's ability to speak Hindi as perhaps a production strategy to make her intelligible to the audience, actress Amy Jackson is unable to speak Hindi. The similarities between the two films are striking with regards their movement from the dangerous West to the serene Punjab (remembering that Preeti narrowly escaped a rape attempt in London and Sara has been threatened with kidnap in Romania). As Indian actresses assert themselves in non-Indian film industries and exploit their racial fluidity and universal beauty aesthetic, white actresses are establishing themselves in roles beyond those previously afforded them in popular Hindi film. [Extracted from the article]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research focused on the production of a novel calcium silicate pigment made from pulverized coal fly ash and its application as a coating pigment in a size press for fiber replacement. Improved specific base paper properties of the newsprint was investigated. This novel coated fly ash based calcium silicate (FACS) pigment and conventional precipitated calcium carbonate (PCC) pigment was applied using a cylindrical laboratory coater. When a 4.3 gsm coat weight of FACS was used during the size press application, the brightness increased 10 points, whereas, when the coat weight of FACS was increased to 7.8 gsm, the brightness increased to 21 points as compared to base newsprint sheet; however, FACS brightness was lower than the PCC coated newsprint sheet. Also, there was a significant gain in other newsprint specific base properties when fly ash based pigment was used. This indicated that it is feasible to utilize a novel fly ash based pigment in the size press coating application to replace fiber in order to reduce production cost, improve specific base properties, and reduce environmental pollution. To the authors' knowledge, this is the first study reporting the application of fly ash as a coating pigment for quality enhancement of newsprint. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biotechnology-based enzymes are challenging in reducing production costs and presenting environmentally friendly technologies. The study deal with an experimental investigation of the bio-catalyst made of Carica-papaya latex in recycling used fibre pulp in industry. The experiments used a test specimen from 5 g of dry pulp mixed with 150 mL of water and a mixture composition of 3.23%. Other similar experiments applied a bio-catalyst from papaya latex by dipping 6 g of unripe papaya into the water. A heating process of the test material was performed at a temperature of 50 °C to optimise the work of enzymes in the pulping process, and then Carica papaya fruit was removed from the container after 3 min. In addition, the characterisation of test materials in the hand-sheets form was realised in dry conditions. The tests carried out include Scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared (FTIR) Spectroscopy, acidity (pH), turbidity, whiteness, and freeness. The results indicated that the addition of bio-activator in water produces bio-ions (positive and negative), which play a vital role in eroding pulp functional groups, influencing the construction of stalagmite micro valleys, and changing the surface morphology of pulp. The release of Bromide, Iodide, Chloride and Fluoride functional groups causes brightening effects and increases the degree of whiteness, impacting the pre-whitening process. Meanwhile, changes in the stalagmite micro valley and the surface morphology of the pulp cause a bulky effect and ultimately reduce the degree of freeness.

Achieving whiteness and opaqueness has been an issue in paint, ceramic, paper, and coating industries from the very beginning. In the past two decades, biomimetics, for the construction of bio-inspired functional materials, has attracted much attention. As an application of biomimetic science, various structural colored materials are investigated by many researchers. The white beetle exoskeletal scales is one of those materials that shows a brilliant white color caused by randomly arranged chitin nanofibers. This material is the inspiration for achieving light weight, efficient, and low-cost white coatings by means of a nanostructure. We used this idea in this research to apply nanofibrous polymeric layer on a substrate, paper sheet in here, and witnessed the possible achievements by varying the nanofiber layer characteristics that underpin its optical properties. We coated nylon and PAN nanofiber layers on the surface of a paper using an electrospinning method and for both polymers desirably high whiteness and opaqueness achieved. Moreover, it was observed that end-use application in printing and writing is easily attained on the nanofiber-coated paper using the common methods. Measuring the properties of the nylon nanofiber-coated paper showed that the tensile strength and hydrophilicity slightly increased depending on the nanofiber layer characteristics. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Structural race-based inequalities in Mexico cannot be denied. Anthropologists and social scientists have thoroughly documented racism at both personal and systemic levels. Following I.M. Young's framework, this paper identifies two possible pathways for the anti-racist movement in Mexico: the liability and the social connection models. The former uses guilt to assign responsibility —it requires an agent to be voluntarily and causally connected to injustice; the latter does not isolate perpetrators but assigns responsibility to all agents who contribute (voluntarily or not) by their actions to the structural processes that produce injustice. After examining the trajectory of the Mexican anti-racist movement, this paper demonstrates that activists are relying too heavily on the liability model. Furthermore, drawing from ethnographic material from Brazil and the United States, the paper suggests that this model is not only unnecessarily confrontational and ineffectual, but potentially counterproductive for the anti-racist movement, as it is prone to provoke a defensive response. In turn, this paper suggests focusing on the structural nature of racism in Mexico and developing ways to communicate this effectively, in order to foster the positive prospects of successful anti-racist activism. [ABSTRACT FROM AUTHOR]

The article focuses on the representation of whiteness in Fae Myenne Ng's Bone (1993), in particular on how the aesthetic and the socio-historical strata of the novel intersect, how by saturating the imagery of Bone with whiteness, Ng conveys the first person Chinese American narrator's positionality and the positionality of other Chinese American characters as members of the Chinese American community and members of broader American society. The images involving whiteness compose a kind of the palimpsest overwritten with personal and communal ethnic watermarks as well as repressed, surfacing and semi-articulated history of Leila's family that she channels into the narrative, having engaged in the process of mentally retracing the past events and recovering the material evidence or rather what remains of it and what she believes will lead her to definitive answers. On the level of narrative imagery, whiteness is intricately interwoven with the traumas plaguing the narrator's family. Explicitly, whiteness represents death, mourning, rejection and erasure, entailing marginalization suffered by Chinese Americans because of their non-normative racial and ethnic status. Yet, implicitly, whiteness is also a constituent element of the images which facilitate the process of healing -- mainly bones and paper. Narrative imagery involving whiteness contributes to the bridging of the past and the present, forming a bridge between generations, a kind of rivet that allows to at least partly retrieve personal wholeness and recapture the broken promises. [ABSTRACT FROM AUTHOR]

This paper reviews and revives a longstanding conversation about race and development studies, which was prominently explored in a collection of papers on race and racism in the journal Progress in Development Studies back in 2006. This revival is timely in the context of a global call to decolonise higher education. Given the central logic of race and racism in European colonialism, and the decolonial argument that colonialism continues in the production and value of knowledge, I examine the presence and absence of race and racism in discussions of decolonising higher education and in development studies. Through a systematic review and content analysis of papers published in six major development studies journals over the past 13 years, I identify where and how race is present in current development scholarship and explore the implications of this for a decolonial turn in development studies. [ABSTRACT FROM AUTHOR]

The article focuses on the representation of whiteness in Fae Myenne Ng's Bone (1993), in particular on how the aesthetic and the socio-historical strata of the novel intersect, how by saturating the imagery of Bone with whiteness, Ng conveys the first person Chinese American narrator's positionality and the positionality of other Chinese American characters as members of the Chinese American community and members of broader American society. The images involving whiteness compose a kind of the palimpsest overwritten with personal and communal ethnic watermarks as well as repressed, surfacing and semi-articulated history of Leila's family that she channels into the narrative, having engaged in the process of mentally retracing the past events and recovering the material evidence or rather what remains of it and what she believes will lead her to definitive answers. On the level of narrative imagery, whiteness is intricately interwoven with the traumas plaguing the narrator's family. Explicitly, whiteness represents death, mourning, rejection and erasure, entailing marginalization suffered by Chinese Americans because of their non-normative racial and ethnic status. Yet, implicitly, whiteness is also a constituent element of the images which facilitate the process of healing - mainly bones and paper. Narrative imagery involving whiteness contributes to the bridging of the past and the present, forming a bridge between generations, a kind of rivet that allows to at least partly retrieve personal wholeness and recapture the broken promises. [ABSTRACT FROM AUTHOR]

In this paper, I discuss the work of W. E. B. Du Bois to expose the disastrous effects of white supremacy in the U.S. and the world. While his early works suggest that white supremacy might be rehabilitated by the careful presentation of contrary evidence, in later works he catalogs the primary features of whiteness, including an infantile comportment, a pathological attachment to innocence, and an epistemic incapacity to absorb evidence of its own error. To capture the scope of the delusion of whiteness on Du Bois's account, I suggest the term "irrevocable license." The remainder of the paper uses Du Bois's account to examine the case of a "Karen"--a white woman who obliviously and inappropriately interferes with the lawful actions of a family of color--and further considers police violence against people of color as an outgrowth of white irrevocable license. [ABSTRACT FROM AUTHOR]