A composite
powder containing microstructured particles obtainable by means of a method in which large particles are combined with
small particles, whereinthe large particles have an average particle
diameter within the range from 0.1 μm to 10 mm,the large particles comprise at least one
polymer,the
small particles are arranged on the surface of the large particles and / or distributed inhomogeneously within the large particles,the
small particles comprise sphere-shaped
precipitated calcium carbonate particles having an
average diameter within the range from 0.05 μm to 50.0 μm, wherein the sphere-shaped
calcium carbonate particles are obtainable by means of a method in whicha. a
calcium hydroxide suspension is initially charged,b.
carbon dioxide or a
carbon dioxide-containing gas mixture is introduced into the suspension from step a. andc.
resultant calcium carbonate particles are separated off,with 0.3% by weight to 0.7% by weight of at least one aminotrisalkylenephosphonic acid being further added.Preferred
application areas of the composite
powder encompass its use as additive, especially as
polymer additive, as additive substance or starting material for compounding, for the production of components, for applications in medical technology and / or in
microtechnology and / or for the production of foamed articles.The invention therefore also provides components obtainable by
selective laser sintering of a composition comprising a composite
powder according to the invention, except for implants for uses in the field of
neurosurgery,
oral surgery, jaw
surgery, facial
surgery, neck
surgery,
nose surgery and ear surgery as well as
hand surgery,
foot surgery,
thorax surgery, rib surgery and
shoulder surgery.The invention also provides the sphere-shaped
calcium carbonate particles which can advantageously be used to produce the composite particles according to the invention, and the use thereof.