New gel coat formulation

Abstract

New gel coat composition, in particular new marine gel coat compositions, a process for their manufacture as well as their use to coat surfaces of articles exposed to light, water and solvents. The gel coats incorporate a precipitated silica having A BET surface of from 150 to 250 M 2 /g A SiO 2 content of more than or equal to 98.5% by weight A Na 2 O content of less than or equal to 0.5% by weight.

1 . A cured or uncured gel coat composition comprising at least one resin and 0.1 to 15 wt %, based on the total weight of the composition, of at least one precipitated silica having
 A BET surface of from 150 to 250 m 2 /g   A SiO 2  content of more than or equal to 98.5% by weight   A Na 2 O content of less than or equal to 0.5% by weight.   
   
   
       2 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a conductivity of less than or equal to 450 μS/cm. 
   
   
       3 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a mean particle size of from 0.1 to 14 μm. 
   
   
       4 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a BET surface of from 170 to 200 m 2 /g. 
   
   
       5 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a SiO 2  content of from 99.0 to 99.9% by weight. 
   
   
       6 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a Na 2 O content of form 0.01 to 0.5% by weight. 
   
   
       7 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a conductivity of from to 1 to 150 μS/cm. 
   
   
       8 . A gel coat composition according to  claim 1 , wherein the at least one precipitated silica has a mean particle size of from 2 to 8.5 μm. 
   
   
       9 . An uncured gel coat composition according to  claim 1  comprising at least one unsaturated polyester resin. 
   
   
       10 . An uncured gel coat composition according to  claim 1 , comprising at least one unsaturated polyester resin having a weight average molecular weight of 1,300 to 110,000. 
   
   
       11 . A gel coat composition according to  claim 1 , further comprising at least one inorganic pigment and/or at least one organic pigment. 
   
   
       12 . A gel coat composition according to  claim 1 , wherein said resin is cured. 
   
   
       13 . A cured gel coat composition according to  claim 1 , comprising at least one polyester resin. 
   
   
       14 . A process for preparing a gel coat composition according to  claim 1 , comprising combining said at least one silica with at least one unsaturated polyester resin to form a gel coat composition, followed by optionally curing said composition. 
   
   
       15 . A process for preparing a gel coat composition according to  claim 14 , comprising curing said composition. 
   
   
       16 . A process for preparing a gel coat composition according to  claim 15 , comprising applying said gel coat composition to an article, followed by curing. 
   
   
       17 . A process for preparing a gel coat composition according to  claim 16 , wherein the article is selected from the group consisting of watercrafts, wind mills, swimming pools, tubs, showers, sanitary ware, tanks, pipes, tanks, ducts, fume stacks, build panels, ships, electrical parts, aircraft components, and electronic components. 
   
   
       18 . An article coated with a gel coat composition according to  claim 1 . 
   
   
       19 . An article according to  claim 18 , wherein said gel coat composition is cured. 
   
   
       20 . An article according to  claim 19 , wherein said article is fiber-reinforced. 
   
   
       21 . An article according to  claim 19 , wherein the article is selected from the group consisting of watercrafts, wind mills, swimming pools, tubs, showers, sanitary ware, tanks, pipes, tanks, ducts, fume stacks, build panels, ships, electrical parts, aircraft components, and electronic components. 
   
   
       22 . An article according to  claim 19 , wherein the gel coat comprises a polyester resin and wherein the article is a watercraft hull.