PROCESS FOR PROVIDING A SURFACE WITH A BARRIER AND A SUBSTRATE BEING PRODUCED ACCORDING TO THE PROCESS

摘要

The present invention relates to a process for providing a substrate with a barrier wherein the process comprises the steps of applying a coating mixture to the surface of the substrate, at least partly drying the coated surface of the substrate and applying a barrier activating solution to the at least partly dried coated surface in order to form a barrier on the surface of the substrate, wherein the coating mixture comprises at least one water soluble polymer and at least one kind of nano-particle. The present invention also relates to a process for forming a film with barrier properties and a paper or board produced according the process.