Method for manufacturing an embossed sheet comprising a ply of water-soluble material

A method for manufacturing an embossed sheet comprising at least one first ply of tissue, at least one second ply of tissue, and at least one ply of water-soluble material arranged between said at least one first ply of tissue and said at least one second ply of tissue,

• the method comprising the steps of:
• embossing said at least one first ply of tissue to form protuberances on one surface of said at least one first ply of tissue;
• embossing said at least one second ply of tissue to form protuberances on one surface of said at least one second ply of tissue;
• humidifying summits of the protuberances of at least part of the protuberances on said at least one first ply of tissue and on said at least one second ply of tissue;
• and
• simultaneously joining the at least one ply of water-soluble material to said at least one first ply of tissue and to said at least one second ply of tissue to cause a local dissolution of the surface of the at least one ply of water-soluble material upon its contact with the humidified summits.