Method and device for warming and hardening filter rods

摘要

Heating and hardening cigarette filters comprising a filter material and a hot-melt adhesive binder comprises passing a single layer of individual filters through a hot air oven to heat the filters to a temperature just above the melting point of the binder and then through a cooler to harden the binder. An independent claim is also included for apparatus for heating and hardening cigarette filters, comprising a conveyor for transporting the filters through an oven and cooler as above.