 The use of GCLs as a separate category of geosynthetics appears to have been in the United States in 1988 in solid waste containment as a backup to a geomembrane.The product was Claymax which is bentonite mixed with an adhesive so as to bond the clay between two geotextiles; one below (the carrier textile) and the other above (the cover textile) the bentonite in the center.About the same time a different product in Germany, Bentofix, was manufactured by placing bentonite powder between two geotextiles and then needle punching the three-components system together.