摘要 |
The invention relates to active ingredient-containing polymer particles comprising a vinyl polymer from 10-80% by weight monomers comprising amino and/or carboxyl groups, which is insoluble in one part of the pH range 0-10 and is soluble in another part of the range, wherein these active ingredient-containing polymer particles comprise 3-1000 parts of active ingredient per part of vinyl polymer, have a particle size in the range 20 nm-8 mum and the vinyl polymer is >50% by weight composed of polymers having a molecular weight of <100 000 daltons. |