Reflecting spherical microcapsules and methods of their production

A method of producing monodisperse spherical microcapsules comprising a shell and a core, the method comprising:

• preparing a first liquid phase containing a first polymerization partner;
• preparing a second liquid phase containing a second polymerization partner, the first liquid phase not being soluble in the second liquid phase, and the second polymerization partner being configured to polymerize with the first polymerization partner under interfacial polymerization conditions;
• dispersing light reflecting solid integral particles in the first liquid phase;
• forming droplets of the first liquid phase including at least one of the light reflecting solid integral particles;
• immersing the droplets in the second liquid phase under the interfacial polymerization conditions, wherein the first polymerization partner and the second polymerization partner polymerize at the surfaces of the droplets forming shells of a polymeric material enclosing the individual droplets;
• and
• fixing the light reflecting solid integral particles to the shells;
• thereby producing monodisperse spherical microcapsules comprising the core and the shell;
• wherein the core comprises 1 to 5 light reflecting solid integral particles per microcapsule;
• and
• wherein the shell comprises the polymeric material.