Also aliphatic glycidyl epoxy resins usually have a low viscosity compared to aromatic epoxy resins. In composite materials, epoxy, polyester or phenolic resins are common. These derivatives form products such as acrylic fibers, glasses, paints, resins, and polymers. These species are used as curing agents in epoxy resins. It dissolves ethyl cellulose, polyvinyl butyral, many oils, alkaloids, gums and natural resins. It is also a precursor to monomers for other resins and polymers. Chemists had begun to recognize that many natural resins and fibers were polymers. Succinic acid is a precursor to some polyesters and a component of some alkyd resins. Epichlorhydrin is a raw material for epoxy resins. Green composites are classified as a biocomposite combined by natural fibers with biodegradable resins. Paint consists of three main components&colon; pigments, resins or binders, and water or solvents. One particular risk associated with epoxy resins is sensitization. Silicones are often prepared from silicone resins via room temperature vulcanization. Any hydroxyls are the result of incomplete conversion to the amine-terminated polymer resins. In general, the polymer is in the form of a filament fabricated from virgin resins.