Restoration of the silhouette “Emperor Nicholas I and the Cadet Bubnov”

В статье представлено описание реставрации силуэта «Император Николай I и кадет Бубнов», переданного наряду с другими силуэтами в лабораторию научной реставрации графики из отдела истории русской культуры Государственного Эрмитажа. Композиция предмета состоит из бумажного силуэта в рамке золотого цвета, наклеенного на черный глянцевый фон, бумажную и картонную подложки. Данный силуэт передан в реставрацию из-за повреждений, имеющих тенденцию к развитию и неблагоприятных как для состояния сохранности бумаги-основы, так и для красочных слоев. Исследования бумаги позволили выявить визуально незаметный слой свинцовых белил на поверхности силуэта. В процессе реставрации была открыта исторически значимая надпись «Подарок Мейбаумъ 4. 28 августа 1835». Мы можем предположить, что надпись указывает на автора силуэта, воспитанника Первого кадетского корпуса Мейбаума, либо на его родственника, подарившего силуэт. С каждым элементом предмета проведены реставрационные мероприятия. Основная часть работ выполнена над бумажным силуэтом, имеющим не только пятна, но и разрывы вследствие деформации бумажной основы и картона. Особенностями оформления композиции после реставрации является инкапсулирование силуэта в полиэфирную пленку, предотвращающую взаимодействие свинцовых белил с воздухом, и крепление всех элементов конструкции по верхнему краю. После реставрации сохранен авторский замысел: инкапсулированный силуэт на черном глянцевом фоне, окаймленный рамкой золотого цвета, крепится к бумажной подложке. The article presents a description of the restoration of the silhouette “Emperor Nicholas I and the Cadet Bubnov” which was transferred along with other silhouettes to the Laboratory for Scientific Restoration of Graphics from the Department of the History of Russian Culture of the State Hermitage Museum. The composition of the subject consists of a paper silhouette in a gold frame, pasted on a glossy black background, paper and cardboard backings. This silhouette was handed over for restoration due to damages that tended to develop and were unfavorable both for the state of preservation of the base paper and for the paint layers. The paper studies made it possible to reveal a visually imperceptible layer of lead white on the silhouette surface. During the restoration process, the historically significant inscription “Gift of Meibaum 4. August 28, 1835” was discovered. We can assume that the inscription points to the author of the silhouette, a student Meibaum studied in the First Cadet Corps, or to his relative who donated the silhouette. Restoration procedures have been carried out with each element of the object. The main part of the work has been done on a paper silhouette, which had not only spots, but also tears due to the deformation of the paper support and cardboard. The features of the composition design after restoration are the encapsulation of the silhouette in a polyester film, which prevents the interaction of lead white with air, and the fastening all structural elements along the upper edge. After the restoration the author's idea has been kept: the encapsulated silhouette on a black glossy background, bordered by the golden frame, is attached to a paper backing.

SAFETY OF PAPER PACKAGING MATERIALS WITH POLYMER COATINGS

Background. Packaging materials that are intended for contact with food are subject to the strictest requirements for their safety. When choosing packaging material for such products, first of all it is necessary to ensure the required level of sanitary and hygienic characteristics. The aim of the study is to assess the safety of moisture-resistant waterproof and moisture-resistant and water-resistant waterproof PPM (paper packaging materials) with a polymer coating. Materials and methods.The object of the study is PPM, made by processing the base paper with coatings based on PVA (polyvinyl alcohol) and PAAEX (polyamidamine-pichlorohydrin). The safety of the developed packaging materials was assessed by organoleptic and physicochemical methods for the presence of foreign tastes and odors, the level of migration of vinyl acetate and epichlorohydrin, the content of zinc, lead, cadmium and microbiological indicators by standard methods. Results. Packaging paper must meet the requirements of current regulations in terms of quality, and its use is allowed subject to compliance with state sanitary norms. Studies of organoleptic characteristics of extracts of paper packaging materials did not reveal the presence of foreign tastes and odors. Determination of the amount of migration of harmful substances, namely vinyl acetate and epichlorohydrin, showed that the transition of the components of the solutions, which are impregnated with paper materials is within acceptable limits. The content of zinc and lead was 25 and 3 times less than the maximum allowed by regulations. The microbiological parameters of the developed paper packaging materials meet the regulatory requirements and allow their use for food packaging. Conclusion. Developed new types of paper packaging materials on the level of migration of toxic compounds (vinyl acetate, epichlorohydrin), heavy metal content and microbiological indicators meet the requirements for packaging both food and non-food products of pharmaceutical, medical, cosmetic and other industries.

Preparation of Modified PVA Copolymer by DAAM/ADH and Cross-Linking Mechanism for Paper

Herein, a novel modified polyvinyl alcohol(DA-IPVA) used as sizing agent was prepared by using diacetone acrylamide(DAAM) as graft monomer and N-(isobutoxymethyl)acrylamide(IBMA) as self-cross-linking monomer. The effect of the amount of DAAM on the properties of emulsion, film and sizing paper was discussed. The surface micro-structure of the sizing paper was characterized by SEM and AFM. The addition of DAAM/ADH and IBMA endowed DA-IPVA with cross-linked active group and increased cross-linking density and hydrophobicity after ADH was added into the emulsion and the cross-linking structure was formed. The enhancing mechanism of surface sizing agent for paper was revealed. The DA-IPVA can be cross-linked on the surface and inside of the paper to form a dense network structure, which improves the bonding force between the fibers. When the mole fraction of DAAM of the cross-linking monomer is 8%, the surface sizing performance of the paper is obviously improved compared with the base paper. The dry and wet strength is increased by 266.5% and 334.3% respectively, and the folding resistance is increased 2946.67%. This study can have a profound impact on the development of the technology of cross-linking surface sizing agent for paper.

Discussion on the Design and Performance of the Whole Packaging Box of Environmentally Friendly Packaging Materials

More and more designers and companies in the packaging industry begin to pay attention to research on environmentally friendly packaging design. From studying the additional functions of packaging to starting to study the environmentally friendly materials of packaging, as well as the “zero-pollution” packaging advocated today, the traditional form and mode of packaging has changed. This article aims to study the design of the overall packaging box of environmentally friendly packaging materials and discuss its performance. In this paper, the platform construction method and the modulus definition classification method are used to calculate the positive axis stiffness of the single-layer board. The effect of coating process on the wear resistance of paper-based materials was studied, the wear resistance of box board base paper and coated box board under different temperatures and different humidity conditions was compared, and the optimal design variable value range was set. The experimental results show that after the first level of optimization, the overall mass of the structure is reduced from the initial 39.42 kg to 31.18 kg and the optimization efficiency is 20.90%; the maximum relative deformation of the flap structure has increased from 0.143 mm to 0.198 mm, despite having the maximum tension. The opening displacement has increased, but it still meets the sealing deformation requirements. The design and performance discussion of the overall packaging box of environmentally friendly packaging materials have been completed relatively well.

A Scientific Analysis of Gold Threads Used in Donggungbi-Wonsam(Ceremonial Robe Worn by a Crown Princess, National Folklore Cultural Heritage No.48)

This study identified material properties through scientific analysis on Jikgeumdan(satin with gold threads) from Donggungbi-Wonsam and the gold threads used in the embroidery. The Donggungbi-Wonsam’s base of gold threads were estimated to have used mulberry fiber’s Korean paper(Hanji) because non-wood-based fibers were observed. The X-ray spectrometer showed that the Tongsuseulan of Donggungbi-Wonsam was a flat gold thread of pure gold and Jikgeumdan of flat silver thread of its Saekdong and Hansam. High sulfur levels were detected in the flat silver thread, which appeared to have formed silver sulfide by either manufacturing process using sulfur or conservation environment. he dragon insignia’s embroidery is also described as two types twisted gold threads; pure gold and alloying-gold and silver. while dragon insignia’s border line is decorated with a twisted gold thread of pure gold. In particular, it was investigated that adhesives such as an animal glue, a protein-based compound by gas chromatography mass spectrometry. Additionally, XRF and Raman spectroscopy analysis on the mixture substances between the metal surface and the base paper of gold threads identified talc and quartz in the gold threads and Seokganju(hematite) in the flat silver threads.

Printability of paper and paperboard surface treatment with gum rosin and derivatives

Purpose This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway. Design/methodology/approach The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured. Findings The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m2, respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface. Originality/value The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

CRACKING PHENOMENA OF COATINGS ON LABEL PAPERS

"The phenomenon of paper coating cracking when folded was studied. Coating mixtures were compared according to their composition, applied on different base paper, to find which combinations of the constituents of the base paper and the paper coating results in a lower tendency towards fold cracking of the coating layer. It was shown that the appropriate selection of pigments (calcium carbonate, kaolin) and binders (starch, latex), whose elastic behavior extensively influences the deformation of paper under physical and mechanical stress, is of central importance. The choice of the base paper plays a significant role as well, it should have the longest and the most numerous cellulose fibers possible in order to avoid fiber breaks and inter- and intra-fiber connections. The content of inorganic substances has the greatest negative effect on deteriorating the physical-mechanical properties of the studied label papers, leading to the deposition of inorganic substances at the joints between the cellulose fibers and reducing their bonding."

Improving the Barrier Properties of Packaging Paper by Polyvinyl Alcohol Based Polymer Coating—Effect of the Base Paper and Nanoclay

The poor barrier properties and hygroscopic nature of cellulosic paper impede the wide application of cellulosic paper as a packaging material. Herein, a polyvinyl alcohol (PVA)-based polymer coating was used to improve the barrier performance of paper through its good ability to form a film. Alkyl ketene dimer (AKD) was used to enhance the water resistance. The effect of the absorptive characteristics of the base paper on the barrier properties was explored, and it was shown that surface-sized base paper provides a better barrier performance than unsized base paper. Nanoclay (Cloisite Na+) was used in the coating formulation to further enhance the barrier performance. The results show that the coating of PVA/AKD/nanoclay dispersion noticeably improved the barrier performance of the paper. The water vapor transmission rate of the base paper was 533 g/m2·day, and it decreased sharply to 1.3 g/m2·day after the application of a double coating because of the complete coverage of the base paper by the PVA-based polymer coating. The coated paper had excellent water resistance owing to its high water contact angle of around 100°. The grease resistance and mechanical properties of the base paper also improved after coating. This work may provide inspiration for improving the barrier properties of packaging paper through the selection of a suitable base paper and coating formulation.

Influence of coating grammage on the utility properties of coated papers

Influence of coating grammage on the utility properties of coated papers.The paper coating offers the opportunity to create a product with high added value, the potential of which has been recognized by both paper mills and polygraphs.Indeed, paraffin coatings have excellent barrier, sliding and strength properties, and also increase the quality and durability of the print. This paper presents the results of the research on the influence of the coating weight on the functional properties of the coated paper. To this end, a commercially available paper was coated with a paraffin emulsionusing various Mayer rods and then tested using standard mechanical, surface, and water absorption tests. It was found that the coating of the base paper, regardless of the amount of the applied mixture, significantly influences its hydrophobic, surface, and strength properties. Papers with the highest coating weight allowed to obtain a paper with increased strength and high surface smoothing. The completed coatings significantly increased the water barrier, regardless of their thickness