Use of a polymer material on the basis of modified hydrocolloids as covering material

Polymeric microcapsule wall material comprising a modified hydrocolloid with a content of.gtoreq.0.1 mass % (m-%) of polymerizable or cross-linkable groups of the general formula:

• ##STR6## in which X stands for --CO--, --COO--, --OCO--, --CONH--, ##STR7## R.sup.1 is a hydrogen atom, a hydroxy, nitrile, halogen, or C.sub.1 -C.sub.8 -alkyl residue;
• R.sup.2 is a saturated or unsaturated, at least bivalent hydrocarbon residue R.sup.3 is a hydrogen atom, a hydroxy group or a C.sub.1 -C.sub.4 alkyl residue;
• n stands for 0 or 1;
• and
• these groups being linked over a linking member with the backbone of the hydrocolloid.