Water soluble substrate with dissolution resistance before immersing in water

摘要

A water soluble substrate (10) comprising a first surface (12) and a second surface (14) opposite said first surface (14), said substrate (10) having at least two coating layers (21, 22) applied to at least one of said first and second surfaces (12, 14), said coating layers (21, 22) being less water soluble than said water soluble substrate (10), wherein said layers (21, 22 ) combined coating covers at least one of said first and second surfaces (12, 14), and where a lubricant (23) is applied between said two coating layers (21, 22).