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В статті розглянуто результати досліджень міцнісних характеристик відбитків, припресованих плівкою. Різноматність технологій оздоблення дозволяє реалізовувати у виданні задум художника чи дизайнера, надає оригінальності, сприяє його просуванню на ринку. Одним із найрозповсюдженіших способів покращення зовнішнього вигляду друкованих видань є технологія припресування плівкою. Останнім часом процеси припресування плівок використовують не тільки на поліграфічних підприємствах, де є великоформатне устаткування, а й в малих друкарнях, які виготовляють поліграфічну продукцію малими накладами, друкуючи цифровим способом друку. На якість процесу припресування плівкою істотно впливають властивості паперу, фарби, плівки, відсоток накладання фарби при цифровому друці, технологічні режими обладнання. Щоб звести до мінімуму виникнення дефектів, потрібно враховувати всі фактори, що впливають на технологічний процес. Крім того, видання характеризуються терміном служби, який визначається механічною міцністю на згинання після технологічних операцій бігування, фальцювання, тиснення й характеризує довговічність видання. Особливу увагу приділяється технологічним режимам ламінаторів, а саме температурі каландрів, швидкості, силі притискування. Залежно від методу друку, цифрового обладнання, до складу фарби (тонеру), можуть входити складники, хімічний склад яких значно погіршує адгезію плівки. Низьку адгезію плівки до задрукованого паперу зумовлюють такі причини: несумісність фарби (тонеру) та клею; наявність компонентів, чутливих до дії високих температур; неправильний вибір параметрів проведення технологічного процесу припресування. Дослідження на міцність відбитка після процесу припресування плівкою дозволили отримати результати, які підтверджують, що при цифровому друці на якість припресування плівкою мають вплив властивості паперу, фарби (тонеру) й технологічні режими обладнання. The research’s results on strength characteristics of laminating imprints are described in the article. The technology of decoration unevenness allows to realize the artist or the designer idea in the publication, gives a unique view, promotes it’s in the market. One of the most common ways of improving the appearance of imprints is apply the laminated films’ technology. Recently, this process is used not only in polygraphic enterprises, where there is large-format equipment but also in small printing offices, which produce printing products with small copes amount, printing by digital printing. The quality of the laminating process is significantly affected by the paper’s quality and properties, ink, film, the overprinting percentage in digital printing, equipment technological aspects. To minimize the occurrence of defects, it is necessary to take into account all the factors, influencing for technological process. In addition, the publications are characterized by the age of service, which is determined by the mechanical flexural strength after machining operations of joint forming, folding, pressing and characterizing the publication’s useful life. The special attention is paid to the laminating aspects, namely the temperature of calenders, the speed, the force of compression. Depending on the printing method, digital equipment, the ink (toner) may include components whose chemical composition significantly affects the film’s adhesion. The low film’s adhesion to the imprint is caused by the following reasons: the incompatibility of the ink (toner) and glue; the presence of components sensitive to the effects of high temperatures; incorrect parameters choice for conducting the laminating process. The research on the print strength after the film laminating process allowed to obtain results confirming that the digital printing affects by the paper’s properties, ink (toner) and the equipment’s technological aspects in the digital print quality. Представлены результаты исследований прочности оттисков, напечатанных цифровым способом печати и припрессованых пленкой. На основе проанализированных исследований показано влияние на прочностные характеристики оттиска бумаги, краски (тонера), технологических режимов оборудования.

A heightened need to control the spread of infectious diseases prompted the current work in which functionalized and innovative antimicrobial tissue paper was developed with a hydrophobic spray-coating of chitosan (Ch) and cellulose nanocrystals (CNCs) composite. It was hypothesized that the hydrophobic nature of chitosan could be counterbalanced by the addition of CNC to maintain fiber formation and water absorbency. Light-weight tissue handsheets were prepared, spray-coated with Ch, CNC, and their composite coating (ChCNC), and tested for antimicrobial activity against Gram-negative bacteria Escherichia coli and a microbial sample from a human hand after using the rest room. Water absorption and strength properties were also analyzed. To activate the surface of cationized tissue paper, an oxygen/helium gas atmospheric plasma treatment was employed on the best performing antimicrobial tissue papers. The highest bactericidal activity was observed with ChCNC-coated tissue paper, inhibiting up to 98% microbial growth. Plasma treatment further improved the antimicrobial activity of the coatings. Water absorption properties were reduced with Ch but increased with CNC. This "self-disinfecting" bactericidal tissue has the potential to be one of the most innovative products for the hygiene industry because it can dry, clean, and resist the infection of surfaces simultaneously, providing significant societal benefits.

This article describes a study on the viability of using waste from the paper industry: biomass boiler ash and green liquor dregs to fabricate mortars and concretes. Both types of ash were characterized by obtaining their chemical and mineralogical composition, their organic matter content, granulometry, adsorption and other common tests for construction materials. Seven different mortars were fabricated, one for reference made up of cement, sand, and water, three in which 10, 20, or 30% of the cement was replaced by biomass ash, and three others in which 10, 20, or 30% of the cement was replaced with dregs. Test specimens were fabricated with these mortars to conduct flexural and compression tests. Flexural strength is reduced for all the mortars studied. Compressive strength increases for the mortars fabricated with biomass ash and decreases for the mortar with dregs. Finally, 5 concretes were made, one of them as a reference (neither biomass ash nor dregs added), two of them with replacements of 10 and 20% of biomass ash instead of cement and another two with replacements of 10 and 20% of dregs instead of cement. The compressive and tensile splitting strength increase when a 10% of ash is replaced and decrease in all the other cases. The modulus of elasticity always decreases.

This study investigates the feasibility of using recycled high density polyethylene (rHDPE), polypropylene (rPP) and old newspaper (rONP) fiber to manufacture experimental composite panels. The panels were made through air-forming and hot press. The effects of the fiber and coupling agent concentration on tensile, flexural, internal bond properties and water absorption and thickness swelling of wood-fiber plastic composites were studied. The use of maleated polypropylene as coupling agent improved the compatibility between the fiber and both plastic matrices and mechanical properties of the resultant composites compared well with those of non-coupled ones. Based on the findings in this work, it appears that recycled materials can be used to manufacture value-added panels without having any significant adverse influence on board properties. It was also found that composites with rHDPE provided moderately superior properties, compared with rPP samples.

The technical properties of three layered cement-bonded boards (CBBs) made from wastepaper and sawdust were investigated. The CBBs were produced at three density levels of 1000, 1200 and 1300 kg/m3 and at four cement/particle ratios of 2.0:1, 2.5:1, 3.0:1 and 3.5:1 on a weight to weight basis. The technical properties evaluated were modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swelling (TS). The MOR values ranged from 4.85 to 11.69 MPa and MOE values ranged from 2.80 to 5.57 GPa. The mean values of WA and TS after 24 h of water soaking of the CBBs ranged from 18.18% to 40.49% and 3.55% to 12.13%, respectively. MOR and MOE of the CBBs increased with increase in board density, but MOR decreased with the increase in cement/particle ratio. On the other hand, WA and TS decreased with increase in board density and cement/particle ratio. CBBs produced from wastepaper and sawdust at cement/particle ratios of 3.0:1 and 3.5:1 are suitable for building construction such as paneling, ceiling and partitioning.

This study evaluates whether the mechanical properties of modulus of rupture (MOR) and modulus of elasticity (MOE) of wood-fiber cement (WFC) sheets are correlated with the nondestructive parameters of stress wave velocity and density of the material. Longitudinal stress wave technique was used to evaluate WFC nondestructively using a total of 117 specimens (measuring each 241 x 51 mm) obtained from 39 WFC sheets. The aim was to establish the correlation between dynamic versus static MOE of the material for predicting the actual mechanical property. Even though short dimension specimens were used, results obtained were encouraging. A correlation coefficient (R) of 0.828 was found when the static MOE of the material was used as a function of nondestructive parameters. A multivariate linear regression analysis using the specimen's density, wave velocity, and dynamic MOE provided the strongest correlation to the static MOE. The correlation observed for MOR as a function of static MOE is within the normal range obtained for wood composites. A nondestructive evaluation (NDE) using full size WFC sheets is recommended and can probably improve the relationship between the static and the predicted MOE.

This study evaluates the usage of waste newspaper as a supplement raw material for laboratory-made single-layer particle-boards. The boards were made of various ratios (75/25, 50/50, 25/75 and 0/100) of waste paper flakes to wood particles mixtures (wt/wt). The effects of press temperature and maleic anhydride on the properties of the boards were determined. Evaluated properties were modulus of rupture, modulus of elasticity, internal bonding strength, and thickness swelling. Panels made from waste newspaper satisfied the modulus of rupture, modulus of elasticity and internal bonding strength requirements of European Norms standards. Performing a statistical analysis of the results, press temperature and maleic anhydride content were found to be positively effective on the mechanical properties at a 95% confidence level. The results from this study indicated that technically waste paper could be a potential substitute material for particleboard manufacture.