Water-dilutable stone impact protection paint and compensation paint, their use and process for their production

Abstract

Disclosed is the preparation of a water-dilutable stone impact protection and of a compensation paint and its use and processes for their production, especially in the automobile industry. The water-dilutable stone impact protection paint contains 20 to 60 wt % binder and 2 to 10 wt % pigments and possibly uncoagulated overspray of water-soluble base paints and the compensation paint contains 40 to 80 wt % binder.

1 . A water-dilutable stone chip protection paint, comprising overspray of water soluble base coats and additional binders, pigments, organic solvents and additives.  
     
     
         2 . The water-dilutable stone chip protection paint of  claim 1  comprising booth waste water with uncoagulated overspray of water soluble base coats.  
     
     
         3 . The water-dilutable stone chip protection paint of  claim 1  or  2  comprising booth waste water upgraded to a solids concentration of from about 10 to 35% by weight, as well as additional binders, pigments, organic solvents and additives.  
     
     
         4 . The water-dilutable stone chip protection paint of any of the preceding claims containing uncoagulated overspray of water soluble base coats of different color shades.  
     
     
         5 . The water-dilutable stone chip protection paint of any of the preceding claims wherein the additional binder is a water compatible blocked isocyanate, a polyurethane resin, polyester resin or melamine resin.  
     
     
         6 . The water-dilutable stone chip protection paint of any of the preceding claims wherein the solvents being added are partly or completely miscible with water.  
     
     
         7 . The water-dilutable stone chip protection paint of any of the preceding claims characterized in that it does not detach itself upon predetermined mechanical load or only from the electrocoat layer.  
     
     
         8 . The water-dilutable stone chip protection paint of any of the preceding claims characterized by having a high rebound resilience.  
     
     
         9 . The water-dilutable stone chip protection paint of any of the preceding claims wherein the binder has elastomeric properties after baking.  
     
     
         10 . The water-dilutable stone chip protection paint of any of the preceding claims characterized in that it comprises from 20 to 60% by weight binders and from 2 to 10% by weight pigments.  
     
     
         11 . The water-dilutable stone chip protection paint of  claim 10  wherein the ratio of binders to pigments is between 5:1 and 12:1.  
     
     
         12 . The water-dilutable stone chip protection paint of any of the preceding claims wherein said pigment is an effect pigment, in particular aluminum bronze.  
     
     
         13 . The water-dilutable stone chip protection paint of the preceding claims wherein said binder is a water compatible blocked isocyanate, a polyurethan, polyester and/or melamine resin.  
     
     
         14 . The water-dilutable stone impact protection paint of  claim 13  wherein said polyester resin has an average molecular weight of from 5,000 to 10,000; exhibits sufficient carboxylic groups which impart to the polyester resin, after neutralization with bases, sufficient water-dilutable characteristics; and contains functional groups, in particular hydroxyl groups, making the polyester resin crosslinkable.  
     
     
         15 . The water-dilutable stone chip protection paint of  claim 13  or  14 , wherein said polyester resin has a OH number of from 20 to 80, in particular of from 30 to 60 and an acid number of from 10 to 50, in particular of from 15 to 35.  
     
     
         16 . The water-dilutable stone chip protection paint of  claims 13  to  15  wherein said polyester resin has a glass transition temperature (Tg) of from −20 to +30° C.  
     
     
         17 . The water-dilutable stone chip protection paint of any of  claims 13  to  16  wherein the polyester is a polycondensation product of a diol and a dicarboxylic acid in the presence of a component containing more than 2 functional groups  
     
     
         18 . The water-dilutable stone chip protection paint of  claim 17  wherein the diol is selected from the group consisting of 1,6-hexanediol, neopentyl glycol, 1,4-dimethylolcyclohexane, hydroxypivalic neopentyl glycol ester (HPN), perhydrogenated bisphenol A, trimethylolpropane and trimethylolpropane monoallyl ether.  
     
     
         19 . The water-dilutable stone chip protection paint of  claim 17  or  18  wherein the dicarboxylic acid is selected from the group consisting of adipic acid, phthalic acid, isophthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid or their possible anhydrides, in particular from the group of dimeric fatty acids.  
     
     
         20 . The water-dilutable stone chip protection paint of any of  claims 17  to  19  wherein the component containing more than 2 functional groups is a triol, a tricarboxylic acid, a monohydroxydicarboxylic acid, in particular a dihydroxymonocarboxylic acid.  
     
     
         21 . The water-dilutable stone chip protection paint of  claim 20  wherein said component containing more than 2 functional groups is trimellithic acid, trimethylolpropane, in particular dimethylolpropionic acid.  
     
     
         22 . The water-dilutable stone chip protection paint of any of the preceding claims additionally comprising organic solvents and additives.  
     
     
         23 . The water-dilutable stone chip protection paint of any of the preceding claims wherein the components to be added to the overspray are added completely or partly in form of a compensation paint.  
     
     
         24 . The water-dilutable stone chip protection paint of  claim 23  wherein the compensation paint comprises form 40 to 80% by weight binders.  
     
     
         25 . The water-dilutable stone chip protection paint of  claim 23  or  24  wherein the compensation paint additionally comprises up to 20% by weight pigments.  
     
     
         26 . The water-dilutable stone chip protection paint of any of  claims 23  to  25  wherein the ratio of binders to pigments in the compensation paint is between 10:1 and 15:1  
     
     
         27 . A process for the preparation of a water-dilutable stone chip protection paint of any of  claims 1  to  26  wherein overspray of water soluble base coats resulting from the application of the coat by spray painting techniques is used.  
     
     
         28 . The process of  claim 27  wherein uncoagulated overspray of water soluble base coats is used.  
     
     
         29 . The process of  claim 27  or  28  wherein spraybooth waste water is used, concentrated to a solid content of from 10 to 35% by weight by removal of water and comprising uncoagulated overspray of water soluble base coats.  
     
     
         30 . The process of any of  claims 27  to  29  wherein overspray of water soluble base coats having different color shades is used.  
     
     
         31 . The process of any of  claims 27  to  30  comprising adding the necessary components in the form of a compensation paint having a solid concentration of from 20 to 80% by weight.  
     
     
         32 . The process of  claim 31  characterized in that the necessary components are binders, pigments, organic solvents and additives.  
     
     
         33 . The use of a water-dilutable stone chip protection paint of any of  claims 1  to  26  for lacquering motorcar bodies having an electro-dip primer coat, a second so-called primar surfacer layer and a third layer comprising a water soluble base coat and a clear coat layer, characterized in that the surfacer layer is replaced by a stone chip protection layer of the stone chip protection paint of any of  claims 1  to  26 , said protection layer having a thickness of from 10 to 20 μm.  
     
     
         34 . The use of a water-dilutable stone chip protection paint of any of  claims 1  to  26  for lacquering motorcar bodies having an electro-dip primer coat, a stone chip protection layer consisting of the stone chip protection paint of any of  claims 1  to  26  in a thickness of from 10 to 20 μm and a clear coat layer.  
     
     
         35 . The use of a water-dilutable stone chip protection paint of any of  claims 1  to  26  for preparing a stone chip protection layer of motorcar bodies having an electro-dip primer coat, a second so-called primar surfacer layer, a third layer comprising a water soluble base coat and a clear coat layer, characterized in that the surfacer layer is replaced by a stone chip protection layer of the stone chip protection paint of any of  claims 1  to  26 , said protection layer having a thickness of from 10 to 20 μm.  
     
     
         36 . The use of a water-dilutable stone chip protection paint of any of  claims 1  to  26  for preparing a stone chip protection layer of motorcar bodies by applying an electro-dip primer coat (KTL), baking said electro-dip primer coat, applying the stone chip protection paint of any of  claims 1  to  26 , drying said stone chip protection paint at a temperature of from 50 to 90° C., applying a base coat, drying said base coat at a temperature of from 50 to 100° C., applying a clear coat, said three layers are baked simultaneously at a temperature of from 130 to 160° C.