• Conservation Science in Museum
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• v.10
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• pp.75-88
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• 2009

The purpose of this study is to determine the lifetime of acrylic resin Paraloid^TM B-72(EMA copolymer), which is widely used as a coating for metallic artifacts to prevent corrosion. Lifetime factor with temperature, selected chromaticity as the test parameter for lifetime prediction. The found result is that the temperature is the most crucial factor influencing the prediction of the lifetime of the EMA copolymer coated iron surface against corrosion. The simulation results, based on Arrhenius Equation, showed that the lifetime prediction of the EMA coated iron surface was 24.5 years at 16℃, 17.1 years at 20℃, and 12.0 years at 24℃, respectively.

• Journal of Conservation Science
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• v.20
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• pp.81-88
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• 2007

For the conservation of wooden coffin from King Muryeong's Tomb we examined weight change, shrinkage rate, color changes, and permeation expansion according to the permeation pretreatment chemicals by producing experimental samples with similar physical properties. The result shows Dammar 2 %(in xylene) as the most excellent treatment for protecting deformation by contraction and strengthening materials which are also maintaining its original colors of wood. Therefore, we could get strengthening conservation treatments of dried wooden coffin materials by using Dammar.

• Conservation Science in Museum
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• v.13
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• pp.51-58
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• 2012

The Conservation Science Team of the National Museum of Korea has carried out the conservation on the mandolin-type bronze sword that was excavated from Weolnae-dong, Yeosu as had been requested by the Research Center of Dolmens in Northeast Asia. The mandolin-type bronze sword from Weolnae-dong, Yeosu is accounted to be the longest one among all the bronze swords of the same type that have ever been excavated until now and it was in a treated condition with the primary conservation treatment already achieved. Due to the corrosion in progress, it was in a very brittle condition being in two separate parts of the upper and lower parts. With the upper part exposed and the lower part with earth, they were urgently collected. The Conservation Science Team carried out the conservation treatment on them by connecting the lower part of the mandolin-type bronze sword to the upper part after making the lower part exposed, and then by using an estimated restoration method for lost portions. When carrying out the conservation treatment, the glass fibers of 10 wt% Paraloid B-72 (in Xylene) was used as a method for strengthening the brittle artifact, and a non-destructive analysis was carried out to identify the ingredients using the X-ray fluorescence spectrometer.

• Journal of Conservation Science
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• v.26 no.3
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• pp.325-334
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• 2010

In order to clarify the effect of consolidant, the artificial porous material with low intensity was manufactured using granite powder and Portland cement. We have prepared four kinds of alkoxysilane system consolidants, a acrylic resin and a epoxy resin and investigated about characteristics before and after consolidation. As a result of the research, Silres BS OH 100 was effective for density and surface hardness. SS-101 with hydrophobicity and Site SX-RO with hydrophilicity had the good durability over salts weathering. On the other hand, Syton HT-50 and Paraloid B72 were easily destructed by salt weathering because they were concentrated on surface area by the low penetration depth. Araldite 2020 was the most effective consolidant for improvement of physical properties.

• Journal of Conservation Science
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• v.17 s.17
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• pp.19-32
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• 2005

The exterior of Korean traditional wooden buildings have been painted with Danchung of painting method using glue and pigments. However because of losing traditional techniques and materials through the period of colonization and industrialization, many problems are occurring today. Especially after several years from painting, occurrence of scalings and flakings in painting layer is a serious problem. To improve weathering resistance of painting layer caused by stress from the difference of swelling and shrinkage between painting layer and wood plate, was examined by weathering tests. The stress is due to the hydrophilic property of wood, mechanical properties(tensile property and stress relaxation) of painting layer, and priming methods by various binders such as glue, acrylic emulsion(Primal AC-3444), acrylic resin(Paraloid B-72). Because stress relaxation of acrylic emulsion of which glasf transition temperature is below room temperature$(7^{\circ}C)$ is high, painting layers with acrylic emulsion generate no scalings and flakings and are in the most durable state in all weathering tests. Priming method which starts from low concentration to high concentration, is more effective to improve durability than other priming methods.

• Journal of Adhesion and Interface
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• v.14 no.3
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• pp.128-134
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• 2013

This study investigated the natural adhesives for ceramics conservation that can be used as a substitution for synthetic resins. Samples were prepared by mixing lacquer with animal glue and the structure and adhesion properties of the samples were analyzed. The structure analysis with FT-IR showed that carbonyl (C=O), amine (N-H) and aromatic (C=C) bonds are increased by adding animal glue on lacquer. Comparing to the viscosity and tensile strength of the sample to the Paraloid B-72 and Araldite rapid type, these natural adhesives can be a substitution for the synthetic resins. Through methodical and intensive study, we expect practical uses of this eco-friendly natural adhesives for ceramics conservation.

• 보존과학연구
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• s.34
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• pp.50-61
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• 2013

The Grave encapsulated by lime soil mixture were excavated with clothing and hemp shoes from the Choseon Dynasty in Gooam, Sacheon. Hemp shoes have wood in the center and their surroundings were made of complex materials including herbaceous ones but the front part was lost or became very fragile. We analyzed the hemp shoes and pre-test of consolidant for conservation treatment of hemp shoes. As a result of analyzing, three kinds of plants were identified. For hemp shoes, Oryza spp, hemp, and one kind of dicotyledones were used and it was analyzed that fabrics attached to the back of Dogaengi was cotton. Conservation methods for pre-test of consolidant, Polyethylene Glycol, Paraloid-B72, Dammar gum, Methyl Cellulose and Silicone resin was selected. The solution was sprayed twice in a 24-hour duration. Properties of consolidant was measured; color difference, glossiness difference, folding streangth and tensile streangth. By comparing the results, PEG was confirmed to the most suitable as consolidant. For the conservation treatment, cleaning and strengthening was conducted. For strengthening treatment, PEG 4000 was selected given that the shoes were made of complex materials. The PEG impregnation method was applied with the PEG 4000 concentration gradually changing from 5% to 80% for reinforcement. Then humidity- controlled drying in order to avoid any rapid environment change.

• Journal of Conservation Science
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• v.30 no.1
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• pp.27-32
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• 2014

The sample book was printed in 1935. Since the books in the early twentieth century were printed using acidic paper, the color of the paper would change to brown over time due to iron corrosion. In addition to corroding iron cores, the acidity of the paper (pH 3.2) also made the paper brown and fragile, as was true in the case of the sample book. To clean the paper of the sample book and to make it strong, we replaced the iron core and performed wet cleaning on the paper to remove contaminants. Then we pressed the sample book dry, and subsequently linening every page with Minoshi($4g/m^2$). Generally, book conservator rebinding the book using wires or threads: however we have devised a new method to rebind the book using colored iron cores. To color the iron core brown, they were dipped in an aqueous coloring solution ($H_2O$, $C_2H_5OH$, $CuSO_4{\cdot}5H_2O$, $FeCl_3{\cdot}6H_2O$); subsequently, a 20% paraloid B-72 was applied to protect the colored iron cores from corrosion.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.150-171
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• 2013

The most important part of conservation treatment of murals is to preserve them against the risk of a damage by injecting fixative into them when the painting loses its cohesion or powderization of pigments occurred due to occurrence of cracks inside the painting layer. However, studies on the stability of fixative used for painting layers of murals are still insufficient. This study manufactured a mural as a specimen and colored it with four kinds of pigments including oyster shell white, cinnabar, malachite and red clay and applied four kinds of fixative, including, Paraloid $B-72^{(R)}$, Caparol-$binder^{(R)}$, glue and Hydoxypropyl $cellulose^{(R)}$. artificially generated environmental changes in temperature, humidity and ultraviolet rays which may occur after the completion of conservation treatment. Then the changes in physical properties were observed in multifaceted ways such as color stability, contact angle, brilliance, adhesive strength and surface. As a result, this study found that ultraviolet rays and hot?humid environment have a large impact on color stability causing changes in brightness and chroma of all painting layers where the fixative were applied, except for oyster shell white and are considered the main factors of decomposition by accelerating the aging process of fixatives applied. In comparison to the synthetic resins that were also tested in this study, the traditional glue showed satisfactory results in terms of color stability and influence preservation and the hydrophile property. As it showed exceptionally outstanding adhesive strength in all painting layers in the aspect of adhesive strength, it is considered to be highly stabile for the fixation treatment of painting layers of mural.

• Conservation Science in Museum
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• v.24
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• pp.117-132
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• 2020

The painting layer of Payathonzu temple mural paintings in the ruins of Bagan Myanmar has been damaged due to various reasons. In this study, the applicability of Neem resin, a traditional Myanmar adhesive, as a fixative on the painting layer was examined. Cow glue and Paraloid B-72 were selected as fixatives in the comparison group, and pseudo-specimens with conditions similar to the original mural paintings were produced to examine the changes before and after applying the fixatives and according to the deterioration experiments. As a result of conducting the experiments and comparing the fixatives, it was found that changes on the surface such as smudge, yellowing and gloss are greater with the application of higher concentration of Neem resin than with other fixatives. However, such changes were relatively small under the condition of 4% concentration. It was also confirmed that chromaticity and glossiness vary greatly between before- and after-application of the fixatives but that such discrepancies tend to decrease at 4% concentration compared to other concentrations. As for fixation strength, it was found that the fixation capacity of Neem resin on the base and painting layers is overall higher than other fixatives as the concentration is increased. Therefore, the applicability of 4% concentration of Neem resin as a fixative on the painting layer was confirmed considering the low surface changes according to environmental factors, low color discrepancy and glossiness, and characteristics of excellent fixation strength. It is believed that the findings of this study could be used as basic data for the preservation of Payathonzu temple mural paintings in the future.