Patent ID: 7579081

Claim:
An opacifying particle comprising a pigment particle having an average particle diameter of from 0.005 to 5 microns and an index of refraction of at least 1.8; a first polymer attached to the surface of the pigment particle via a silane residue, wherein the first polymer is an addition polymer of at least one ethylenically unsaturated monomer; and a shell comprising a second polymer, the second polymer being formed from at least one ethylenically unsaturated monomer comprising at least one water-soluble monomer selected from the group consisting of an ethylenically unsaturated alcohol-functional monomer, an ethylenically unsaturated inorganic acid-functional monomer, an ethylenically unsaturated carboxylic acid-functional monomer, an ethylenically unsaturated amide-functional monomer, an ethylenically unsaturated amine-functional monomer, and a combination thereof, which substantially encapsulates the pigment particle having the attached first polymer.