Hydroxybenzoic acid as pH buffer and corrosion inhibitor for antifreeze containing organosiloxane-silicate copolymers

摘要

This invention relates to single-phase antifreeze or coolant concentrates comprising an alcohol, a corrosion inhibiting amount of a water-soluble organosiloxane-silicate copolymer corrosion inhibitor and an organic basic pH buffer capable of buffering pH in the range of about 9 to about 11 comprising a hydroxybenzoic acid or mixtures thereof. The concentrates are used as coolants either undiluted or upon dilution with about 25 percent to about 90 percent by weight of water based upon the total weight of the concentrate. The alcohol is preferably ethylene glycol. The coolant compositions are effective in providing protection against corrosion of all metals and alloys used in industrial heat exchangers are especially effective in inhibiting the corrosion of aluminum internal combustion engine and radiator components.