Today’s invention is for wearers of shoelaces.
Laces have a tendency to be made of material which forms good knots.
Their frictional surface is a disadvantage, however, when trying to feed aglets through eyelets.
It’s especially problematic when the laces bind against one another -either when opening the lacing to put the shoes on or when your feet swell and the laces lock locally against one another (causing circulation problems and pain).
The proposed solution is to create laces with a low-friction coating everywhere except for the end-sections involved in bows etc. This could be achieved by coating the central section of laces in a layer of ptfe-type material.