| 摘要 |
Foamable aqueous compositions can be used to form light-blocking and light-colored foamed, opacifying elements with one or more dry foamed layers. The compositions contain: (a) 0.05 to 20 weight % of porous particles comprising a continuous polymeric phase and a first set of discrete pores, the porous particles having a mode particle size of 2 to 50 μιη; (b) at least 20 weight % of a binder material (that can be curable); (c) 0.1 to 30 weight % of one or more additives including dispersants, plasticizers, inorganic or organic pigments or dyes, thickeners, flame retardants, biocides, fungicides, optical brighteners, tinting colorants, metal flakes, and inorganic or organic fillers; (d) water; and (e) at least 0.001 weight % of an opacifying colorant different from (c), which opacifying colorant absorbs electromagnetic radiation. The foamable aqueous composition can be aerated, disposed on a porous substrate, dried, and crushed on that porous substrate. |
