Varnish dammar

Polybutadiene Vinyl acetate/butyl acrylate copolymer Vinyl chloride/ethylene copolymer binder, paper treatment Silica, colloidal binder, paper varnishes Dammar... 

A varnish is often appHed on top of the paint layers. A varnish serves two purposes as a protective coating and also for an optical effect that enriches the colors of the painting. A traditional varnish consists of a natural plant resin dissolved or fused in a Hquid for appHcation to the surface (see Resins, natural). There are two types of varnish resins hard ones, the most important of which is copal, and soft ones, notably dammar and mastic. The hard resins are fossil, and to convert these to a fluid state, they are fused in oil at high temperature. The soft resins dissolve in organic solvents, eg, turpentine. The natural resin varnishes discolor over time and also become less soluble, making removal in case of failure more difficult (see Paint and FINNISH removers). Thus the use of more stable synthetic resins, such as certain methacrylates and cycHc ketone resins, has become quite common, especially in conservation practice. 

Damm, m. dam, dike, bank (Med.) perineum Dammar-finiis, m. dammar varnish, -harz, n dammar resin, dammar, dammen, v.t. dam, dam up, stop up curb. Dammerde, /. mold, humus (Founding) pit sand. 

Dammar Trees of family Dipterocapacaea Torch fuel varnish... 

Natural resins Pine resins, sandarac, copals, mastic, dammar, amber, frankincense, benzoe, styrax, myrrh, (plant resins) shellac (animal resin) tar and pitch (from thermal treatment of plant resins or wood) Varnishes, coatings, waterproofing materials, paint binders, ingredients of cosmetic and pharmaceutical preparations... 

Dammar resin was introduced into Europe in the nineteenth century, mainly as a paint varnish It is still used today since it has good optical properties and low acidity. It is derived from various species (the genus Hopea and Shorea of the Dipterocarpaceae family). It is characterised by tetracyclic triterpenoids of the dammarane series and contains minor amounts of pentacyclic triterpenoids of the series of olanane, ursane and hopane. It also contains a polymeric fraction named polycadinene or [S-resene. Dammar resin triterpenoids undergo oxidation with ageing, as described for the components of mastic resin. 

S. Zumbuhl, R. Knochenmuss, S. Wiilfert, F. Dubois, M.J. Dale, and R. Zenobi, A Graphite Assisted Laser Desorption/Ionisation Study of Light induced Aging in Triterpene Dammar and Mastic Varnishes, Anal. Chem., 70, 707 715 (1998). 

G.A. Van der Doelen, K.J. Van den Berg, and JJ. Boon, A Comparison of Weatherometer Aged Dammar Varnishes and Aged Varnishes from Paintings, in Proceedings of the Conference Art et Chimie La couleur, J. Goupy and J.P. Mohen (Eds), Paris, France, 1998, CNRS Editions, Paris, 2000, pp. 146 149. 

J. Boon, and G. Van der Doelen, Advances in the Current Understanding of Aged Dammar and Mastic Triterpenoid Varnishes on the Molecular Level, in Postprints of Fimis, Material Aesthetik Geschichte, International Kolloquium, AdR, Braunschweig, 1998, pp. 92 104. 

In addition to GC/MS, high performance liquid chromatography (HPLC/MS) has been used to analyse natural resins in ancient samples, particularly for paint varnishes containing mastic and dammar resins [34]. A partial limitation of chromatographic techniques is that they do not permit the analysis of the polymeric fraction or insoluble fraction that may be present in the native resins or formed in the course of ageing. Techniques based on the direct introduction of the sample in the mass spectrometer such as direct temperature resolved mass spectrometry (DTMS), direct exposure mass spectrometry (DE-MS) and direct inlet mass spectrometry (DI-MS), and on analytical pyrolysis (Py-GC/MS), have been employed as complementary techniques to obtain preliminary information on the... 

In the nineteenth century dammar, a soft resin derived from trees of southern Asia was introduced in Europe and used for making colourless varnish. Mixed with oil of turpentine it has become the preferred varnish for oil painting, due to its superior optical properties and better ageing stability than the other natural resins. 

The terpenoid resins commonly used as artists materials were colophony, Venice turpentine, mastic, dammar, copals and sandarac, and most of the scientific literature concerning the identification of Old Master varnishes and the study of their degradation focuses on these resins. 

Figure 8. Oxidative gain in weight of film of dammar varnish prepared from xylene solution. , under daylight fluorescent lamps at 240 ft-c intensity and 90°F, 20% r.h. , partially protected from the light in aust-free box.

Open-pore wood varnish DBP/blown castor oil (0.5 1), melamine resin, dammar or ketone resin NC PL resin = 1 0.5 1... 

Naturally drying oils, including dammar, Japanese lacquer and shellac, are suitable for lacquers and varnishes because they dry quickly, although the film... 

The first online TLC-MS attempt in the field of triterpenoids was done only in 2005 in the study of the photo-oxidation of natural di- and triterpenoid resins used as paint varnishes [10], The resinous samples were applied onto a cellulose-coated TLC plate, which afterward was subjected to direct MALDI-TOF-MS analysis without any development. The plates were only sprayed with a saturated ethanol solution of 2,5-dihydroxybenzoic acid as matrix to assist the ionization of compounds. Triterpenoids were observed as protonated molecules or as sodium clusters. Dammaradienone, dammaradienol, nor-a-amyrone, and dammarenolic, oleanonic, and ursonic acid were detected in dammar resin moronic acid, masticadienonic acid, and 3-0-acetyl-3-epi(iso)masticadienonic acid were found in mastic resin and diterpenoid abietane and pimarane acids were present in colophony. The induced aging process produced oxidized triterpenoids, which were observed in the MS spectra... 

Feller, R. L. (1966). First description of dammar picture varnish translated. Bull. American Group... 

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