Abstract: A glycol-based antifreeze/coolant concentrate to be blended in coolant in a cooling system of a vehicle is disclosed, which can effectively inhibit occurrence of cavitation damage in the cooling system while suppressing production of nitrosoamine which is a known carcinogenic substance. A glycol-based antifreeze/coolant concentrate of the present invention contains a 0.05-8.0 wt. % p-toluate and a 0.01-1.0 wt. % molybdate.

Abstract: An antifreeze/coolant composition is disclosed, which can effectively inhibit corrosion of metals, particularly cast aluminum and cast iron, and can also inhibit cavitation damage to metals in an engine cooling system. The antifreeze/coolant composition comprises a glycol as the chief ingredient, 0.1-0.5% by weight of at least one ingredient selected from among hexanoic acid heptanoic acid and their salts, and 0.1-0.5% by weight of at least one ingredient selected from among alkylbenzoic acids having C.sub.1 -C.sub.5 alkyl and their salts.

Abstract: An antifreeze/coolant position is disclosed, which can effectively inhibit corrosion of metals, particularly cast aluminum and cast iron, and can also inhibit cavitation damage to metals in an engine cooling system. The anitifreeze/coolant composition comprises a glycol as the chief ingredient, 0.1-0.5% by weight of at least on ingredient selected from among C.sub.6 -C.sub.12 aliphatic monobasic acids and their salts, and 0.1-5.0% by weight of at least one ingredient selected from among cinnamic acid, alkylcinnamic acids, alkoxycinnanic acids and their salts.

Abstract: An antifreeze/coolant composition is disclosed, which can effectively inhibit corrosion of metals, particularly cast aluminum and cast iron, and can also inhibit cavitation damage to metals in an engine cooling system. The antifreeze/coolant composition comprises a glycol as the chief ingredient, 0.1-0.5% by weight of at least one ingredient selected from among C.sub.6 -C.sub.12 aliphatic monobasic acids and their salts, and 0.1-0.5% by weight of at least one ingredient selected from among alkoxybenzoic acids having C.sub.1 -C.sub.5 alkoxy and their salts.

Abstract: An effective metal corrosion inhibitive coolant composition having an excellent pH stabilizing property is disclosed, comprising a glycol as a main ingredient, at least one C 4-C 16 alkenylsuccinic acid or its alkali metal salt in an amount of 0.5-5.0 wt. %, and at least one benzoic acid or its derivative in an amount of 0.5-5.0 wt. %. This coolant composition is further characterized in that no phosphates, amine salts, silicates, borates, or nitrites are contained to avoid their detrimental side effects.

Abstract: Coolant compositions are disclosed which include only a minimum amount of metal corrosion inhibitor. The coolant compositions effectively inhibit: (1) metal corrosion; (2) precipitation of the included metal corrosion inhibitor; (3) oxidative deterioration of the included glycol; (4) lowering of the pH value of coolant fluid; and (5) chemical reaction with hard water components. A coolant composition of the invention includes an alkylbenzoic acid (or acids) or a salt (or salts) thereof, a hydrocarbon triazole and an alkali nitrate in addition to a glycol (or glycols) as a base, water and others. It is characteristic that the coolant compositions of the present invention do not include any aliphatic monobasic acids.

Abstract: An additive to be added to coolant or antifreeze concentrate is disclosed. The additive includes at least one ingredient selected from the group consisting of alkoxybenzoic acids and their amine salts, alkali metal salts and ammonium salts.

Abstract: A system for evaluating the metal corrosion preventiveness of a coolant is disclosed, comprising a reference electrode (1), a working electrode (2) made of an iron material, preferably cast iron, and a voltage meter (3). The voltage meter is electrically connected with the reference electrode and the working electrode such that the redox potential to be generated between the two electrodes in the coolant (C) can be measured by the voltage meter when the two electrodes are partially submerged separately in the coolant. The system can provide an evaluation of the metal corrosion preventiveness of the coolant from the measurement of the redox potential. The cast iron for the working electrode may advantageously be surface-treated by tempering means or alkalization means.

Abstract: A vibration damper of a high polymer resin sheet which contains epizoelectric ceramic powder and a cloth layer placed therein including carbon fibers, which provides excellent as well as consistent and reliable damping effects in a relatively wide temperature range and also a method for producing the vibration damper.