I have never heard of Washi. It's very interesting to learn about this tree and paper made out of it. It must have been very exciting for you to visit the factory as you're using the paper. I also didn't know about plastic used in Japanese paper. I am not sure about paper in Switzerland but I will investigate to learn more as I'm trying to put as little burden on the environment as I can :)
Thank you for sharing and have a nice day!