• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.61-64
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• 2000

FT-IR/ATR analysis shows that the oriental lacquer coating network degrades mostly in the unsaturated side chain. The rate of increase in carbonyl intensity (a measure of photodegradation) during the accelerated weathering test was substantially different for the unstabilized and stabilized samples; adding 2 wt% HALS into the oriental lacquer formulation enhanced photostabilization up to three times. Weight loss measurements, another indication of photodegradation, and SEM analysis support this conclusion. Despite the presence of the photo-stabilizer, the other properties of the lacquer were not significantly affected. In particular, the curing behavior of purified lacquer (PL) and HALS-stabilized samples is similar, although the in-situ DETA analysis showed that addition of HALS can slightly retard the cure reaction rate in oriental lacquer coating. It is hypothesized that this cure retardation may be related to the salt formation between HALS and acid of oriental lacquer.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.04a
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• pp.380-390
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• 2007

The purpose of this study is to make a functional Hanji treated with an oriental lacquer which has various functionalities. The raw oriental lacquer produced in China was used in this study This lacquer was diluted with ethanol and terpene in different solvent ratios. The diluted lacquer in the solvents had two layers. The upper layer was solvent soluble and the lower contained precipitates. Hanji was treated with the solvent solubles and the mixture containing precipitates, and then properties of the Hanji were evaluated. The oriental lacquer consisted of 25.04% of water, 60% of urushiol, 3.13% of nitrogen-containing compounds, and 5.66% of gum. The pH of oriental lacquer was 5.3 and the viscosity was 1680 cP. The average weight, thickness, and density of Hanji treated with oriental lacquer tended to gradually decreased as the lower concentration of lacquer was used and as the solvent soluble was treated. Tensile strength of the treated Hanji decreased when the diluted lacquer was used and Hanji treated with terpene dilutes at the ratio of lacquer to solvent of 1:5 (v/v) showed higher tensile strength than ones treated with ethanol dilutes. The folding endurance decreased as the less concentrated lacquer was used and the highest value was obtained when 1:40 (v/v) of lacquer to solvent ratio in both ethanol and terpene mixture. Absorption ratio was higher in the Hanji treated with ethanol mixture, treated with the lacquer in higher concentration, and treated with ethanol mixture. Hanji treated with ethanol dilutes at 1:20 (v/v) and the lower ratio of lacquer to solvent showed a hydrophobic property. Amount of the bound dye materials tended to be decreasing as the concentration of lacquer becomes lower and it was higher in Hanji treated with ethanol mixture than with terpene mixture. Color of Hanji treated with the solvent diluted mixture was Y to YR-type, whereas that of Hanji treated with raw oriental lacquer was Y-type, terpene

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.70-76
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• 2007

The raw oriental lacquer produced in China was used in this study. This lacquer was diluted with ethanol and terpene in different solvent ratios. The diluted lacquer in the solvents had two layers. The upper layer was solvent soluble and the lower contained precipitates. Hanji was treated with the solvent solubles and the mixture containing precipitates, and then properties of the Hanji were evaluated. The average weight, thickness, and density of Hanji treated with oriental lacquer tended to gradually be decreased as the lower concentration of lacquer was used and as the solvent soluble was treated. Tensile strength of the treated Hanji decreased when the diluted lacquer was used and Hanji treated with terpene dilution at the ratio of lacquer to solvent of 1:5 (v/v) showed higher tensile strength than ones treated with ethanol dilution. The folding endurance decreased as the less concentrated lacquer was used and the highest value was obtained when 1:40 (v/v) of lacquer to solvent ratio in both ethanol and terpene mixture. Absorption ratio was higher in the Hanji treated with ethanol mixture, treated with the lacquer in lower concentration, and treated with ethanol mixture. Hanji treated with ethanol dilution at 1:20 (v/v) and the lower ratio of lacquer to solvent showed a hydrophobic property. Amount of the bound dye materials tended to be decreasing as the concentration of lacquer became lower and it was higher in Hanji treated with ethanol mixture than with terpene mixture.

• Journal of Pharmacopuncture
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• v.5 no.1 s.8
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• pp.159-169
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• 2002

Objective: It will be examined in this research whether Lacquer poison can be used as an distinguished treatment to cure incurable diseases by considering literature existing and various papers. Method: I studies origin, alias, species, toxicity, effect, treatment, component, medical action and contraindication of Rhus vemiciflua stokes through various kinds literatures. Results: Sap of Rhus vemiciflua stokes that is used for medical purposes, has an effect on anti-tumor, anti-oxidation, hangover cure, and gastritis suppression. Even though urushiol and fIavonoids, the main ingredient of lacquer, has medical cure effects. but urushiol results in a dermatropic allergy. Sincc xylem of a Rhus vemiciflua stokes, however. does not induce the allergy but has medical efficacy, research on this topic is needed.

• Journal of Radiation Industry
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• v.12 no.4
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• pp.333-336
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• 2018

Natural lacquer was cured at room temperature at a relative humidity of 60% at $27^{\circ}C$ to obtain a lacquer film. Photolysis of lacquer was investigated by irradiating 1~75 kGy of gamma ray to this lacquer film. No significant changes were observed in the range of 1~10 kGy radiation. As the radiation doses were increased, the white spots were increased in the scanning electron microscope photographs. The increase of the white dots of the lacquer surface shows that the lacquer is degradation by radiation. As a result of IR spectral analysis of the lacquer surface with increasing irradiation dose, there was no significant change in $3,445cm^{-1}$ hydroxide group, $2,900cm^{-1}$ hydrocarbon group, and $993cm^{-1}$ triene group. However, the $1,745cm^{-1}$ carbonyl group was found to increase, and the $1,715cm^{-1}$ unsaturated hydrocarbon group and the $1,463cm^{-1}$ methylene group showed a tendency to decrease.

• Macromolecular Research
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• v.14 no.6
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• pp.617-623
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• 2006

In order to achieve an oriental lacquer (OL) film with a thick consistency, UV-curable silicone acrylate (SA) was added to OL by a dual curing process. The addition of 5 wt% UV-curable SA to the OL fomulation enabled the preparation via a single drying step of a $77{\mu}m-thick$ film exhibiting excellent surface properties. FTIR-ATR was used to investigate the effect of UV-curable SA on the behavior of film formation during curing, and the relaxation behavior of the produced films was investigated by dielectric spectroscopy. Dielectric properties were measured in the frequency range $10^{-2}-10^5\;Hz$ at various temperatures between -100 and $200^{\circ}C$. The results demonstrated that OL modified by UV-curable SA has a higher glass transition temperature and stronger secondary relaxation at a lower temperature than the conventional OL system. The OL film modified with UV-curable SA was presumed to be harder at the surface and tougher than conventional OL film.

• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.715-719
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• 1997

In order to study the dielectric properties of the oriental lacquer films, three different films have been prepared differing purification and curing procedures. Dielectric properties were measured in the frequency range of 1 Hz to 105 Hz at various temperatures between - 50 ℃ and 150 ℃. The DEA using 1 Hz showed that glass transition and secondary relaxation temperatures of oriental lacquer film are very time dependent. In addition, the frequency-independent negative peak between 25 ℃ and 45 ℃ was observed, which could represent the formation of crosslink by laccase enzyme during heating. On the contrary, the high temperature cured film showed a hardly noticeable negative peak at the temperature range. The relationship between thermodynamic properties and chemical structures has been discussed based on the analysis of the dielectric relaxation behavior using the Cole-Cole plot and the dielectric relaxation intensity.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.87-90
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• 2008

The purpose of this experiment is to understand a possibility for the techniques of collecting the Korean Rhus lacquer by the traditional method(Hwachil) against the diminishing lacquer industry. Hwachil method, making use of fire to collect lacquer, is practiced at only some areas, but the lacquer is very efficacious for foods and oriental medicine. A comparative experiment between traditional method and new machine method by processing unit 5 kg of lacquer tree was made to improve Hwachil method technically. The results showed that the machine method produced more about 45% of lacquer than the traditional one. The traditional method, moreover, needed intense labour quality and high leveled techniques, which caused to bring physical sufferings. In comparison with the traditional method for the collecting time required, the machine one showed to take more than minutes per a unit. But the machine method was easy and convenient to handle the machine without special techniques.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1169-1180
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• 2005

First, I read all the materials, including Dongeuibogam(Encyclopedia Medica Koreana), classical writings on Lacca sinica exsiccata, herbal writings on lacquer poison, and herbal books on how to treat lacquer poison. And then after 1 examined all the details on qi and taste of Lacca sinica exsiccata, its efficacy, detoxification, lacquer poison, and its effects on body symptom, 1 got the following results. The order of frequency that Lacca sinica exsiccata is used in Dongeuibogam is pressure-feeling, blood circulation, and insect biting. Its way of intake is not so much through herb-boiling or powdered medicine as through hand-made pills. When medicine is used in the form of pills, the Lacca sinica exsiccata is more included among other ingredients. When old doctors treated pressure-feeling in the chest, they mixed up other herbs, with not putting more emphasis on the efficacy of lacquer 010 doctors believed that toxicity of Lacca sinica exsiccata is not having its own poison, but having biased dominance in the use of its qE and taste. The way or detoxification or Lacca sinica exsiccata is used in the order of crab-boiled water, egg, Xanthoxylum piperitum, Perilla frutescens, Astar tataricus, a weeping willow, iron-tempered water, and Allium toberosum. Special point in detoxificating lacquer poison is that they used medicines for well-ciruculating pulmonary stream, medicines for promoting to urinate or discharge by helping large colons to move, medicines for making the lacquer scar small, medicines for helping digest, and medicines for improving vessel function in the poisoned area. With the above results, the more profound study, based on the crab-boiled water and egg, is expected to go on to increase the effect on the one hand, and to make the new way of lessening or removing the toxicity of lacquer with more safe use on the other hand.

• Journal of Conservation Science
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• v.26 no.3
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• pp.247-258
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• 2010

We conducted optical microscopy, infra-red spectroscopy and SEM-EDS analysis of the lacquer layers on the wooden coffins excavated from King Muryeong's Tomb. We found four varnishing methods according to the sub-materials of lacquer layers: The lacquer of wooden coffins with black paint layer on the surface were classified with two groups; single layer and three layers. The lacquer of wooden coffins without black paint layer on the surface were classified with two groups; single layer and two layers. IR spectra of the laquer were same as those of the oriental laquer. The SEM-EDS analysis showed that the lacquer layers were mixed with iron, copper and calcium.