Bonded abrasive shellac

Bond Type. Most bonded abrasive products are produced with either a vitreous (glass or ceramic) or a resinoid (usually phenoHc resin) bond. Bonding agents such as mbber, shellac, sodium siHcate, magnesium oxychloride, or metal are used for special appHcations. 

Bonded abrasives Phenolics Epoxy Alkyd Natural rubber SBR Shellac Polyimide Grinding wheel... 

Modem civilization would not be possible without bonded abrasive products. By the year 1825 sand, emeiy, and even diamond were being bonded together with shellac for use in abrasive sticks and wheels. Rubber bonded wheels were introduced in 1857, the sodium silicate and the vitrified bond just after the Civil War, and the phenolic resin bond in 1923. The metal bond was introduced for diamond wheels in 1940. 

Shellac dissolved in alcohol or mixed with alkalines is rarely used any longer due to prevalence of resin bonds with similar characteristics of flexibility for abrasives such as cutoff wheels. 

The bond in abrasive wheels may be ceramic, silicate of soda, resin, shellac, rubber, or magnesium oxychloride. 

Natural resins have been used as adhesives. Shellac is used in bonding mica splittings to form micaboard and used in abrasives. Gum arable is used in remoistenable adhesives. Copal gums are used in spirit-soluble lino cements. 

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