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Developing environmentally friendly barrier coatings as an alternative to petroleum-based polymer packaging is a challenge. Cellulose nanofibres (CNF) films have exhibited great potential as water and gas barrier layers. Recycled paper was multi-layer coated with three commercial CNF (mechanical (M-CNF), TEMPO (T-CNF) and carboxymethylated (C-CNF)) using two metering systems (wound rod and blade micrometer) and two drying methods (tension-free contact drying and air drying). The coatability and rheological behaviour of the CNF suspensions were analysed. The gas, water and grease barrier properties of the CNF coated papers were determined and compared with the results of paper coated with cationic starch. The three CNF suspensions and the starch suspension were successfully coated using both metering systems. In the multi-layer coating, air drying yielded higher coat weights than contact drying, and the difference was more noticeable in M-CNF and T-CNF coated samples. A lack of uniformity observed in CNF coatings increased with the number of coating layers. M-CNF coated samples had a whitish surface with a uniform appearance, but coating was insufficiently compact to provide barrier properties. T-CNF coating exhibited a cracked surface and consequently provided no barrier properties. Drying stresses caused breakage of T-CNF coating, which could be explained by the drop in apparent viscosity at much lower rheological shear stresses in the T-CNF suspension. C-CNF showed successful coatability and provided barrier properties to paper with both metering systems and drying methods. Air permeance decreased considerably and the water wettability of the paper decreased by 60% compared to the reference paper, even with a single coating layer (about 1 g·m−2). In addition, a greaseproof paper (grease resistance >1800 s and kit no >10) was obtained with multi-layer C-CNF coating. Although water vapour permeability at 90 % RH and 20 °C decreased slightly with a single layer of CN

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality.

Es wurde eine Machbarkeitsstudie durchgeführt um festzustellen ob der Ersatz von fluorhaltigen Chemikalien bei einer Papierverpackung mit Lebensmittelkontakt für den Erhalt einer Fettbarriere möglich ist bzw. ob weiterführende Forschungen in diesem Gebiet sinnvoll sind. Die Studie sollte die wichtigsten Eigenschaften des Papiers charakterisieren um festzustellen welche Rolle das Fluor spielte und wo es im Papierfaserverbund vorliegt. Charakterisiert wurden mechanische und morphologische Eigenschaften, sowie das Abstoßungsvermögen polarer und apolarer Flüssigkeiten. Mechanisch physikalische Prüfverfahren, EDX-ESEM, Kontaktwinkelbestimmungen und Bestimmung der Adsorptionskapazität einzelner Zellstoffe wurden hierfür eingesetzt. Das Ziel der Studie war es, in einer Entscheidungsmatrix Vorteile und Nachteile möglicher Alternativen zu Fluorchemikalien darzustellen. Anhand der Matrix sollte entschieden werden, in welche Richtung weiter geforscht werden könnte.*****A feasibility study was performed to asses if fluorochemicals, which are used to produce paper packaging for foodstuff with a fat and grease barrier, could be replaced resp. if investing in further research is reasonable. The study should characterize and analyze the prominent properties of the paper to determine the role and distribution of fluorine in the fiber compound. Characterized were mechanical and morphological properties as well as repellence against polar and apolar liquids. To determine these attributes mechanic physical testing methods, EDX-ESEM, contact angle measurements and determinations of adsorption capacities of different cellulose pulp were done. The goal of the study was to present a decision matrix which listed possible surrogates for fluorochemicals. The outcome of this decision matrix could highline the direction of the further research and investments.

In this study, antimicrobial packaging was prepared by mixing colloidal silver nanoparticles with cellulose nanofiber (CNF) and depositing this hybrid coating (CNF/Ag) as a layer on different paper substrates. The CNF/Ag-coated papers were then characterized by scanning electron microscopy (SEM). In addition, their antimicrobial activity, and barrier and strength properties were assessed. SEM showed deposition of Ag nanoparticles on the surface of CNF and formation of a relatively smooth, dense coating layer on the paper surface. The results also demonstrated that the CNF/Ag coating exhibited good antibacterial activity against Escherichia coli (Gramnegative) and Staphylococcus aureus (Gram-positive) bacteria. Although the coating coverage was influenced by paper surface characteristics and coat weights, almost all properties (except water absorption of greaseproof paper) including the water vapor transmission rate, oil resistance, and tensile strength of the CNF/Ag-coated papers were improved in comparison with uncoated papers, Postprint (published version)

This letter presents the design, simulation, fabrication, and characterization of an LC-resonator-based chipless RFID tag. The ID-generating circuit is designed based on a reconfigurable LC resonance circuit. Phase position modulation (PPM) coding is used for the enhancement of the coding capacity. The tag has been realized on packaging paper using all printing technique. In fabrication, overprinting process has been investigated as an effective pathway for the improvement of the conductivities. The tag with 4.25-bit coding capacity has been examined using a sweeping frequency signal transmitted from a vector network analyzer, and experimental results confirm the feasibility of the proposed chipless tag. With further optimizations, the tag can be used in the item-level tracking and identification applications, especially for the management of paper tickets and banknotes., QC 20130503