3. Resenes
These are oxygenated compounds, but are not affected either by alkalies or acids. In fact, they are more or less neutral substances being devoid of characteristic functional groups, and, therefore, do not exhibit any characteristic chemical properties. Interestingly, they are immune to oxidizing agents and variant climatic conditions, a fact which essentially attributes the resins containing them one of their major plus points for the manufacture of varnishes. A few important examples of resenes are as follows:
Dracoresene – Derived from the scales of the fruit of Dragon’s Blood i.e., Daemonorops draco Bl. (and other species) belonging to the natural order (Arecaceae).
Masticoresene – Derived from Mastic-an oleo-resin obtained from Pistacia lentiscus Linn belonging to family: Anacardiaceae.
Fluavil – Obtained from Gutta-percha and also from the bark of various trees. Guttapercha is hard and has a very low elasticity. X-ray diffraction studies have
