Cleaning System Utilizing an Organic Cleaning Solvent and a Pressurized Fluid Solvent

Abstract

A cleaning system that utilizes an organic cleaning solvent and pressurized fluid solvent is disclosed. The system has no conventional evaporative hot air drying cycle. Instead, the system utilizes the solubility of the organic solvent in pressurized fluid solvent as well as the physical properties of pressurized fluid solvent.

1 . A process for cleaning substrates comprising:
 placing the substrates to be cleaned in a vessel,   adding organic solvent to the vessel;   cleaning the substrates with an organic solvent;   removing a portion of the organic solvent from the vessel;   adding pressurized fluid solvent to the vessel;   removing the pressurized fluid solvent from the vessel; and   removing the substrates from the vessel.   
     
     
         2 . The process of  claim 1  wherein the organic solvent comprises a cyclic terpene. 
     
     
         3 . The process of  claim 2  wherein the cyclic terpene:
 is soluble in carbon dioxide between 600 and 1050 pounds per square inch and between 5 and 30 degrees Celsius;   has a specific gravity of greater than approximately 0.800;   has a dispersion Hansen solubility parameter of between 13.0 (MPa) 1/2  and 17.5 (MPa) 1/2 ;   has a polar Hansen solubility parameter of between 0.5 (MPa) 1/2  and 9.0 (MPa) 1/2 ; and   has a hydrogen bonding Hansen solubility parameter of between 0.0 (MPa) 1/2  and 10.5 (MPa) 1/2 .   
     
     
         4 . The process of  claim 3  wherein the cyclic terpene further:
 has an evaporation rate of lower than 50 (based on n-butyl acetate=100); and   has a flash point greater than 100 degrees Fahrenheit.   
     
     
         5 . The process of  claim 4  wherein the cyclic terpene is selected from a group including α-terpene isomers; pine oil; α-pinene isomers; d-limonene; and mixtures thereof.