Literally, a Sealant is a viscous material which becomes solid after application. The main uses of a sealant are either to form a protection barrier, to seal two substrates together, or to fill gaps or holes. Basically this is a material which has the adhesive and cohesive properties to form a seal.

Sealants form a "bridge" between the surfaces and offer several advantages like versatility, chemical resistance, and weather resistance. Main market applications are building and construction, transportation and Do-It-Yourself.

Sealants are classified according to their physical properties: Elastic sealants have high recovery (over 70%), plastic sealants display only slight or no recovery at all (up to 20%) and Elasto-plastic and plasto-elastic sealants with properties in between.