Corrosion inhibitors

Claim 1

A CORROSION INHIBITOR COMPOSITION COMPRISING (1) AN ALKYL ACID PHOSPHATE SALT OF AN N-ALKYL-DIAMINOALKANE IN WHICH THE ALKYL GROUP OF THE ACID PHOSPHATE CONTAINS FROM ABOUT 6 TO ABOUT 20 CARBON ATOMS AND THE ALKYL GROUP OF SAID DIAMINOALKANE CONTAINS FROM ABOUT 8 TO ABOUT 18 CARBON ATOMS, AND (2) FROM ABOUT 0.1% TO ABOUT 25% BY WEIGHT, BASED ON SAID SALT, OF THE MIXED CONDENSATION PRODUCT OF (A) ONE EQUIVALENT OF AN NALKYL-DIETHANOLAMINE CONTAINING FROM 8 TO 18 CARBON ATOMS IN THE ALKYL GROUP AND N-METHYL-DIETHANOLAMINE WITH (B) ONE EQUIVALENT OF THE REACTION PRODUCT OF A TERPENE HAVING THE FORMULA C10H16 AND A BOILING POINT RANGING FROM ABOUT 150* TO ABOUT 185*C. WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF AN ALPHA, BETA-UNSATURATED POLYCARBOXYLIC ACID, ANHYDRIDE AND ESTER THEREOF, SAID TERPENE AND SAID COMPOUND HAVING BEEN REACTED AT A TEMPERATURE OF FROM ABOUT 150* TO ABOUT 300*C. TO FORM SAID REACTION PRODUCT, SAID N-ALKYLDIETHANOLAMINE AND N-METHYL-DIETHANOLAMINE HAVING BEEN CONDENSED WITH SAID REACTION PRODUCT AT A TEMPERATURE OF FROM ABOUT 80* TO ABOUT 200*C. TO FORM SAID MIXED CONDENSATION PRODUCT, AND SAID N-ALKYL-DIETHANOLAMINE BEING UTILIZED IN THE CONDENSATION IN A CONCENTRATION OF FROM ABOUT 0.2 TO ABOUT 0.4 EQUIVALENTS PER 1 EQUIVALENT OF SAID REACTION PRODUCT.