| 摘要 |
Multi-layered polymer particles are provided to ensure improved hiding power and be useful as an opacity agent in paints, paper coatings, and molding compositions. A multi-layered polymer particle comprises a core and at least one hard shell layer formed on the core, wherein the core consists of an inorganic pigment core particle having a refractive index of 1.8 or more, and an alkali-swellable polymer that covers the core particle and is able to form pores after drying. The core particle is at least one inorganic pigment selected from titanium dioxide, zinc oxide, lithopone, or antimony oxide. The alkali-swellable polymer is a copolymer of a monomer mixture consisting of 50-80wt% of at least one ethylenically unsaturated monomer and 20-50wt% of at least one hydrophilic acid monomer. |
