Oriental lacquer

Strain gages may be applied to the test unit at all points where high stresses are anticipated, provided that the configuration of the units permits such techniques. The use of finite element analysis, models, brittle lacquer, etc., is recommended to confirm the proper location of strain gages. Three-element strain gages are recommended in critical areas to permit determination of the shear stresses and to eliminate the need for exact orientation of the gages. 

Figure 5 shows the XPS angular dependence of the fracture surface of a sample. The ratios of the ester carbonyl carbon and ether carbon to the total amount of carbon are plotted on the ordinate. The 30O angle means that the thickness measured is assumed to be about a half of that with an angle of 60°. The results show that the concentration of the ester bond observed on the interfacial substrate surface decreases toward the fracture interface, suggesting that the hydrocarbon groups are oriented toward the outside (lacquer side). The concentration of the ether group (a component of the lacquer) on the interfacial substrate surface is about one-third that on the interfacial lacquer surface, and it is presumed that the lacquer remained like islands on the substrate surface at an area ratio of 1 3. 

Sodium ion-selective field-effect transistors (Na+ ISFETs) were prepared by using three different types of polymeric matrix materials, such as polyvinyl chloride, bio-compatible polymer (polyurethane) and Urushi (natural oriental lacquer). Their electrochemical characteristics were discussed in connection with their characteristics of polymeric matrix membranes. 

Other compound coatings. A number of other compoimds can be induced to crystallise in a submicroscopic platelet form imitating aragonite, and suspended in a variety of lacquers or resins, which can be applied in the same way as essence d orient. 

Impey, O.R. and Tregear, M. (1983). Oriental Lacquer. Ashmolean Museum. 

Lacquer differs entirely from varnish and lac, although the terms may be mistakenly interchanged in the literature. Varnish is a natural resin dissolved in a solvent. After the solution has been applied, the solvent volatilizes, leaving a shiny glaze. Lac is the deposit of the Coccus lacca insect, which is collected from certain trees in East India. This deposit is refined and dissolved in a solvent. Both varnish and lac coatings are much less stable than the coating found on oriental lacquer ware. 

This discussion has been intended to provide a review of the technical study of oriental lacquer. This unique material varies greatly in composition, methods of manufacture, and artistic style. Because of this, it offers a wide variety of exciting problems to solve. A bibliography of selected papers has been included as a guide for further study. In addition to this, a detailed annotated bibliography on technical analysis of lacquer, containing in excess of 380 entries, will be published soon (60). 

H. Linhui and Z. Tianya, Proc. Internal. Symp. Oriental Lacquers, 1993, pi, (published, May 1995). 

J. Kumanotani, Proc. Internat. Symp. Oriental Lacquers, May 1993, p59. 

To establish authenticity of oil paintings and works of art, an examination of the surface-coating resin and pigment may be reqnired. In older objects, resins may be oleoresins, wood rosin, amber, dammar, shellac, oriental lacquers, or other natural resins. 

As an example, a fluorocarbon surface layer can be obtained by dissolving a small amount (less than 1%) of a polymerizable fluorosurfactant in a lacquer and cross-linking the surfactant monolayer formed at the surface. Figure 17.31 shows two fluorocarbon surfactants, one polymerizable (a) and the other non-reactive (b), used in such an experiment. The surfactants were added to a poly(methyl methacrylate) (PMMA) lacquer. PMMA is more polar than the hydrocarbon part of the surfactant so the surfactant orients at the film-air interface with... 

J. Kumanotani, Heterogeneity in the Surface of Oriental Lacquer Films, Xllth Internal. Conf. Org. Coat. Sci. and Technol., July 7-11, 1986, Athens, Greece, p. 195. 

Urushiol yu- rii-she- 61, ii-, - ol [ISV, fr. Japanese urushi lacquer -f ISV -ol] (1908) n. A mixture of pyrocatechol derivatives with saturated or unsaturated side chains of 15 or 17 carbon atoms that is an oily toxic irritant principle present in poison ivy and some related plants (genus Rhus) and in oriental lacquers derived from such plants. Langenheim JH (2003) Plant resins chemistry, evolution ecology and ethnobotany. Timber Press, Portland, OR Paint pigment, drying oils, polymers, resins, naval stores, cellulosics esters, and ink vehicles, vol 3. American Society for Testing and Material, Conshohocken, PA, 2001. 

Qin M, Mitchell JD, Vogl O. Oriental lacquer. 10. The South East Asian lacquer. J Macromol SciA Pure Appl Chem. 1996 33 1791-1803. 

Snyder DM. An overview of oriental lacquer art and chemistry of the original high-tech coating. J Chem Educ. 1989 66 977-80. 

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