Patent ID: 6676847
Filing Date: 2004-01-13
Classification: C09K,C23F

Abstract:
An acid based antifreeze composition consisting essentially of:a. a major amount of a water soluble liquid alcohol freezing point depressant; b. from about 0.8 to about 10.0 weight percent of a monobasic carboxylic acid compound or the alkali metal salt thereof; c. a salt which is at least one selected from the group consisting of sodium nitrate, potassium nitrate, magnesium nitrate, calcium nitrate, lithium nitrate, sodium nitrite, potassium nitrite, magnesium nitrite, calcium nitrite, lithium nitrite and combinations thereof in an amount of from 0.001 to about 10.0 percent by weight; d. from about 0.01 to about 10.0 weight percent of an azole compound having at least three nitrogen molecules selected from the group consisting of tolytriazole, hydrocarbyl triazole, benzotriazole, mercaptobenzothizole, pyrazoles, isooxazoles, isothiazoles, thiazoles, thiadiazole salts, 1,2,3-benzotriazole, 1,2,3-tolyltriazole, sodium 2-mercaptobenzothiazole, and combinations thereof; e. from about 0.001 to about 5.0 weight percent of a molybdate compound; f. a silicone-silicate copolymer in an amount of about 0.01 to about 10.0 percent by weight; and g. from about 0.001 to about 5.0 percent by weight by weight of a polyvinylpyrrolidone.