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US 4,904,393 AGranted
Method for controlling overspray in paint spray booths
AssigneeW. R. Grace & Co.-Conn.
InventorsDavid B. Mitchell, Thomas P. Curran
Life of this patent
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Abstract
A composition and method for detackifying paint spray booth water containing particles from paint spray is disclosed which uses a reaction product of an aldehyde with either a urea or an aminotriazine or both, and at least one of; (i) a hydrolyzed polyacrylamide; (ii) certain modified tannins in further combination with diallyldialkyl quaternary ammonium polymers or polymers derived by reacting certain dialkylamines with epihalohydrins.
Claims18
A method of detackifying spray booth water containing paint particles from paint spray comprising the steps of:
- (a) adding to the spray booth water at least about 150 ppm of a polymer which is a reaction product of an aldehyde with either a urea or an aminotriazine, or both, and which has a molecular weight of at least about 5000;
- (b) adding to the spray booth water at least about 100 ppm total of a modified tannin which is a reaction product of a condensed tannin with both an aldehyde and an amino compound, together with either a diallydialkyl quaternary ammonium polymer or a polymer derived by reacting dimethylamine, diethylamine or methylethamine with an epihalohydrin;
- (c) providing a pH above about 6.5 in the spray booth water such that the polymer added in step (a) and the modified tannin added in step (b) form a pin floc which is dispersed in the spray booth water for detackification, with the polymer added in step (b) stabilizing said pin floc and improving detackification and (d) separating the floc and paint particles from said spray booth water.
Dependencies are inferred from the claim text.