• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.457-463
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• 2013

PURPOSE. The purpose of this study was to compare the effect of a diode laser and traditional irrigants on the bond strength of self-adhesive cement. MATERIALS AND METHODS. Fifty-five incisors extracted due to periodontal problems were used. All teeth were instrumented using a set of rotary root canal instruments. The post spaces were enlarged for a No.14 (diameter, 1.4 mm) Snowlight (Abrasive technology, OH, USA) glass fiber reinforced composite post with matching drill. The teeth were randomly divided into 5 experimental groups of 11 teeth each. The post spaces were treated with the followings: Group 1: 5 mL 0.9% physiological saline; Group 2: 5 mL 5.25% sodium hypochlorite; Group 3: 5 mL 17% ethylene diamine tetra acetic acid (EDTA), Group 4: 37% orthophosphoric acid and Group 5: Photodynamic diode laser irradiation for 1 minute after application of light-active dye solution. Snowlight posts were luted with self-adhesive resin cement. Each root was sectioned perpendicular to its long axis to create 1 mm thick specimens. The push-out bond strength test method was used to measure bond strength. One tooth from each group was processed for scanning electron microscopic analysis. RESULTS. Bond strength values were as follow: Group 1 = 4.15 MPa; Group 2 = 3.00 MPa; Group 3 = 4.45 MPa; Group 4 = 6.96 MPa; and Group 5 = 8.93 MPa. These values were analysed using one-way ANOVA and Tukey honestly significant difference test (P<.05). Significantly higher bond strength values were obtained with the diode laser and orthophosphoric acid (P<.05). There were no differences found between the other groups (P> .05). CONCLUSION. Orthophosphoric acid and EDTA were more effective methods for removing the smear layer than the diode laser. However, the diode laser and orthophosphoric acid were more effective at the cement dentin interface than the EDTA, Therefore, modifying the smear layer may be more effective when a self-adhesive system is used.

• Journal of Conservation Science
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• v.34 no.3
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• pp.143-155
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• 2018

In this study, we investigated the properties and manufacturing methods of soil mural finishing layers fabricated using animal glue, starch adhesive(wheat paste), and Dobak glue. We assessed the workability and weatherproofing properties of the earthen plaster and finishing layers fabricated using concentrations of 3%, 5%, 7% and 10% for each adhesive. The results showed that a mixture using 3% or 5% starch adhesive or 3% Dobak glue was suitable for constructing the finishing layer. For finishing layers made with animal glue, earthen plaster had poor workability. It was dry and easily broken as the concentrations of animal glue increased. However, specimens made with low concentrations of animal glue did not exhibit surface deterioration after a freezing-thawing test. Therefore, animal glue mixtures could possibly be used for constructing finishing layers in concentrations lower than 3%. Mixtures containing starch adhesive produced plasters with good workability. Additionally, starch adhesive enhanced compression strength. However, when starch adhesive was mixed at concentrations above 7%, the surface exhibited roughening and staining in freezing-thawing tests. When Dobak glue was used in mixtures, it enhanced compression strength, but concentrations above 5% produced specimens with surface cracking. For concentrations of 3%, there were no cracks and the specimens were stable after freezing-thawing tests, so concentrations below 3% of Dobak glue are suitable for constructing finishing layers. We expect this study will be useful for restoring the traditional technology of soil mural finishing layers and suggest using adhesives to construct the finishing layer.

• Korean Journal of Heritage: History & Science
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• v.49 no.4
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• pp.114-125
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• 2016

Lacquer is one of the most widely used natural resin in East Asia since Neolithic Age. As a major ingredient of lacquerware, lacquer is waterproof, insect-proof and rot-proof to be durable and anti-abrasion, generally utilized for mainly painting purpose. According to lacquerware excavated from several sites of Japan and China, lacquerware seems to appear in Neolithic Age. On the other hand in case of excavation research in Korea, lacquerwares are found after the Bronze Age. The initial purpose of lacquer is estimated to be adhesive, regarding the literatures mentioning bitumen(Yeoksceong ), animal glue(Kyeo) and egg alumen(Nanbaek). Especially piece of jar coffin unearthed in Pyeongtaek Daechu-ri site had trace of restoration by lacquer and hemp as an evidence of lacquer for adhesion in Pre-Three Kingdoms period. Since then a trend to restore the broken ceramics with lacquer and decorate with golden foil lasted especially in Joseon Dynasty. In the field of gold plated lacquer method, mother-of-pearl inlaying technique for lacquerware and restoration of buildings, lacquer is still used as adhesive. Due to matter of reversibility lacquer is being avoided for conservation and restoration of cultural heritage. Lacquer as a traditional material for adhesive since ancient times, however, has advantage in adhesion strength and durability. Because synthetic resin adhesive has problem of emission of volatile organic compounds and aging over time, lacquer receives attention recently. On the contrary, by combination adhesive from mixing lacquer and animal glue, already proved the possibility of applicability and chemical modification. A research to utilize lacquer as modern paint or functional material is also conducted continuously also in China and Japan. To put traditional material into practical use and modernize, chemical research from the molecular level of the lacquer is necessary in the near future.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.633-640
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• 1994

The tensile bond strength to dentin was measured for three glass-ionomer cement and composite resin combinations: two light-curing glass-ionomer cements(Vitrebond and XR - Ionomer) and one traditional glass - ionomer cement(Ketac - Bond), two adhesive systems(Scotchbond, and XR - Bonding System), and a corresponding composite resin. The bond strength of this "sandwich" was also compared with that of the same cements used in bulk. Vitredbond showed a significantly higher bond strength in bulk than did the other two cements. Of the sandwiches, the XR - Iomomer and XR - Bond combination showed a bond strength significantly higher than that of the Vitrebond and Scotchbond or Ketac- bond and Scotchbond combination. The fracture of the bond was mainly adhesive for Vitrebond, cohesive for XR - Ionomer when used in bulk and adhesive - cohesive when used in a sandwich, and cohesive for Ketac-Bond.

• Journal of Conservation Science
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• v.30 no.3
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• pp.307-315
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• 2014

The gold textile is Korean traditional weaving technique using the gold thread since 5th century. The making technique of gold thread was written in various references, but it is severed because the gold thread weaving equipment and sumptuous moods were forbidden in the early 18th century. There are some studies of traditional gold thread which are mainly about conservation treatment of cleaning and strength. To restore traditional gold thread, investigation of material and manufacturing technique is vitally required. The gold threads are composed of gold leaf, adhesive and base sheet. Gold leaf and base sheet are available for investigation because they are exposed to the surface, whereas adhesive is not easy to investigate because it is not exposed to the surface. In this study, samples are made of pure and impure gold, animal glue and lacquer, and various types of Hanji based on domestic and foreign references to compare materials for gold threads. As a result of morphological character and stability evaluation, the optimum materials for the restoration of gold threads are pure gold, animal glue and Dochimji(smoothing paper by beating). This study is expected to be basic data for manufacturing gold threads techniques and modernization of traditional gold threads hereafter research.

• Journal of Adhesion and Interface
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• v.17 no.3
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• pp.89-95
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• 2016

An environmentally friendly water-based pressure sensitive adhesive (PSA) was designed in an attempt to replace the solvent-based adhesive for dry lamination used in flexible food packaging films. Instead of using a low molecular weight surfactant, which may have variable material properties, a high molecular weight dispersant was used for emulsification. A polymeric nano-dispersant (PND) was synthesized using solution polymerization, and it was used as a micelle seed in the surfactant, resulting in the synthesis of a core/shell grafted acrylic adhesive. The shell and core exhibited different $T_g$ values, so that the initial adhesion strength and holding power were complemented by the film's flexibility, which is required to provide good adhesion of thin films. Results showed that the PSA designed in this study using the PND instead of traditional low molecular weight surfactant had adhesive properties applicable to the flexible packaging with appropriate tack.

• Journal of Conservation Science
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• v.25 no.1
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• pp.39-47
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• 2009

This paper reports a study on physical properties of the traditional adhesives for developing natural adhesives. This is to certify that the superiority of tradition through systematic surveys and experiments as well. We used three kinds of starches differing fermentation time(7 years, 4 years 8 months, and 2 years 8 months) which are fermented from wheat flour starches. The amylose contents, total sugar contents, crystallinity, particle size and shape, viscosity, pH, and adhesive strength were examined. The effect of fermentation time on physical properties of fermented wheat flour were studied. It was found that fermentation time effect various physical properties such as total sugar contents, amylose contents, crystallinity, viscosity, and so on.

• Journal of Conservation Science
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• v.29 no.1
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• pp.25-33
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• 2013

This study aims to investigate the film performance by physical properties of glue and gelatin in traditional paint(Dancheong). To do this, homemade, commercial glue and gelatin was selected and evaluated water reaction and weatherproof. The result, the highest gel strength, gelatin was better than acrylic acid ester resin, when compared with hygroscopic property and adhesive property. And that was better than in any others, when compared with water-proofing.

• Journal of Sericultural and Entomological Science
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• v.47 no.1
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• pp.41-47
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• 2005

Kayagum is a traditional musical instrument in Korea. Kayagum strings are usually made of raw silk. It needs good vibration and durability. This study was carried out to increase durability of the strings by chemical treatment and manufacture of silk/polyester and silk/wild silk compound yarn. In this study, we used MKW-810(water solube acrylic adhesive)and polyvinyl alcohol as a adhesive. Before the twisting, the raw silk wet on the string manufacture process. The adhesive reagent were added in this process. And compound yarn were prepated by domestic silk, polyester and wild silk(antheraea pernyi) for make of Kayagum strings, respectively. The result are as follows. 1. Tenacity and elongation of the strings are almost same between none and chemical treatment. However number of extension cycling to breaks of the strings was largely increased by chemical treatment. Number of extension cycling to breaks of the strings is very important and useful item to check durability of the strings. The stiffness of the strings were almost same between none and adhesive treatment 2. Tenacity of the silk/polyester strings is largely decreased by increasing of polyester portion, but elongation of the silk/polyester strings increased. However tenacity of the silk/polyester(mono filament) strings are higher than that of silk strings. 3. Tenacity of the domestic silk/wild silk strings is largely decreased by increasing of wild silk portion, but elongation of the domestic silk/wild silk strings is almost same among silk and domestic silk/wild silk strings.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.4
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• pp.44-53
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• 2014

This research were aimed at developing starches which have high preservability and high bonding strength from corn starch, modified cationic and oxidized corn starches, as compared to the fermented wheat starch. On the lining that attaching the base paper on the back of the work with paste, the coating weight was determined by the solid contents of the paste rather than the viscosity of paste. Adhesive strength and stiffness were also determined by the solid contents of the paste. Corn starch had lower solid contents, higher viscosity, and higher adhesive strength than other starches. In the iodine stain to the surface of peeled base paper off, paste deeply penetrated into the traditional Hanji than modern Hanji. And oxidized starch paste deeply penetrated into the paper layer than the cationic starch.