Klucel is a family of non-ionic cellulose ethers. They feature a remarkable combination of properties which make them quite interesting to book conservators for use as consolidants. Klucel is soluble in water below 38 C, and insoluble in water above 40 C. It is also soluble in many polar organic solvents, including methyl alcohol, ethyl alcohol, and isopropyl alcohol (95%). It is insoluble in toluene, xylene, and trichloethylene. Klucels are highly surface-active, and extremely flexible without plasticizers in films and coatings. Light cream in color, solutions are clear, smooth, and remarkably free from gels and fibers. They are heat sealable and are not tacky at high humidity. Once prepared, Klucel E has a low viscosity, forming a thin fixative or glue. Viscosity in 10% solution is 150-700. Glass transition temperature is 120 C. 7 mPas.