Non-aqueous solvent composition and its use as barrier liquid

Abstract

A non-aqueous solvent composition comprising 0 to 10 wt. % of N-alkyl pyrrolidone, 0 to 5 wt. % of dimethyl sulfoxide, 10 to 50 wt. % of γ-butyrolactone, 10 to 50 wt. % of at least one monoalcohol, 10 to 60 wt. % of at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, other than N-alkyl pyrrolidone, and consisting of carbon, hydrogen, oxygen and, optionally, nitrogen, and 0 to 10 wt. % of at least one additive. The non-aqueous solvent composition can be used as barrier liquid within a coating installation of an industrial mass production coating line for the application of water-borne two-component polyurethane coatings.

What is claimed is: 
     
         1 . A method of operating a coating installation of an industrial mass production coating line, wherein the method comprises:
 providing the coating installation comprising a release valve for a non-aqueous hardener component; and   filling the coating installation downstream of the non-aqueous hardener release valve with a non-aqueous solvent composition comprising:
 0 to 10 wt. % of N-alkyl pyrrolidone, 
 0 to 5 wt. % of dimethyl sulfoxide, 
 10 to 50 wt. % of γ-butyrolactone, 
 10 to 50 wt. % of at least one monoalcohol, 
 10 to 60 wt. % of at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, other than N-alkyl pyrrolidone, and consisting of carbon, hydrogen, and oxygen and, optionally, nitrogen, and 
 0 to 10 wt. % of at least one additive. 
   
     
     
         2 . The method of  claim 1 , wherein filling the coating installation downstream of the non-aqueous hardener release valve comprises entirely filling the coating installation downstream of the non-aqueous hardener release valve with the non-aqueous solvent composition. 
     
     
         3 . The method of  claim 1 , wherein the coating installation further comprises a mixer and a connection between the non-aqueous hardener release valve and an entrance of the mixer, and wherein filling the coating installation downstream of the non-aqueous hardener release valve comprises filling the connection between the non-aqueous hardener release valve and the entrance of the mixer with the non-aqueous solvent composition. 
     
     
         4 . The method of  claim 3 , wherein the coating installation further comprises storage tanks for an aqueous base component and the non-aqueous hardener component, circulation lines for the components from the respective storage tanks, and a connection between each circulating line and the mixer, wherein the connection between the circulating line for the non-aqueous hardener component and the mixer includes the non-aqueous hardener release valve, and wherein filling the coating installation downstream of the non-aqueous hardener release valve comprises filling the connection between the non-aqueous hardener release valve and the entrance of the mixer with the non-aqueous solvent composition. 
     
     
         5 . The method of  claim 4 , wherein the coating installation further comprises spray-application devices and connecting pipework downstream of the non-aqueous hardener release valve, and wherein filling the coating installation downstream of the non-aqueous hardener release valve comprises filling the mixer, the spray-application devices, and connecting pipework with the non-aqueous solvent composition. 
     
     
         6 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the at least one additive is selected from the group consisting of defoamers, wetting agents, and surfactants. 
     
     
         7 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the γ-butyrolactone makes up 25 to 35 wt. % of the non-aqueous solvent composition. 
     
     
         8 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the at least one monoalcohol makes up 25 to 35 wt. % of the non-aqueous solvent composition. 
     
     
         9 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, other than N-alkyl pyrrolidone, and consisting of carbon, hydrogen, and oxygen makes up 25 to 35 wt. % of the non-aqueous solvent composition. 
     
     
         10 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition comprising 25 to 35 wt. % of γ-butyrolactone, 25 to 35 wt. % of at least one monoalcohol, and 30 to 50 wt. % of at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, and consisting of carbon, hydrogen and oxygen. 
     
     
         11 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the monoalcohol is a C3-C8 monoalcohol. 
     
     
         12 . The method of  claim 11 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the C3-C8 monoalcohol is a saturated C3-C8 monoalcohol. 
     
     
         13 . The method of  claim 1 , wherein the coating installation downstream of the non-aqueous hardener release valve is filled with the non-aqueous solvent composition wherein the non-aqueous solvent composition is free of n-alkyl pyrrolidone. 
     
     
         14 . A method of operating a coating installation of an industrial mass production coating line, wherein the method comprises:
 providing the coating installation comprising storage tanks for an aqueous base component and a non-aqueous hardener component, circulation lines for the components from the respective storage tanks, and a connection between each circulating line and a mixer, wherein the connection between the circulating line for the non-aqueous hardener component and the mixer includes a non-aqueous hardener release valve; and   filling the connection between the non-aqueous hardener release valve and the entrance of the mixer with a non-aqueous solvent composition comprising:
 0 to 10 wt. % of N-alkyl pyrrolidone, 
 0 to 5 wt. % of dimethyl sulfoxide, 
 10 to 50 wt. % of γ-butyrolactone, 
 10 to 50 wt. % of at least one monoalcohol, 
 10 to 60 wt. % of at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, other than N-alkyl pyrrolidone, and consisting of carbon, hydrogen, and oxygen and, optionally, nitrogen, and 
 0 to 10 wt. % of at least one additive. 
   
     
     
         15 . A method of operating a coating installation of an industrial mass production coating line, wherein the method comprises:
 providing the coating installation comprising a release valve for a non-aqueous hardener component; and   filling the coating installation downstream of the non-aqueous hardener release valve with a non-aqueous solvent composition comprising:
 0 to 5 wt. % of dimethyl sulfoxide, 
 25 to 35 wt. % of γ-butyrolactone, 
 25 to 35 wt. % of at least one saturated C3-C8 monoalcohol, 
 30 to 50 wt. % of at least one organic solvent inert towards isocyanate groups, other than γ-butyrolactone, other than N-alkyl pyrrolidone, and consisting of carbon, hydrogen, and oxygen and, optionally, nitrogen, and 
 0 to 10 wt. % of at least one additive. 
 wherein the non-aqueous solvent composition is free of N-alkyl pyrrolidone.