Method of producing a contactless chip card or a contact/contactless hybrid chip card with improved flatness

A method of manufacturing a contactless chip card or a contact/contactless hybrid chip card having an antenna support, two card bodies on either side of said antenna support and an electronic module or a chip linked to the antenna comprising:

• a first lamination step comprising fusing two homogeneous sheets of thermoplastic on each side of said antenna support by pressing at a temperature sufficient for the material of which the sheets are made to soften and to flow wholly so as to eliminate any differences in thickness from the antenna support and to form a plasticised antenna support having even faces, and
• a second lamination step carried out after a period of time corresponding to the period of time necessary for said sheets of thermoplastic to be solidified, said second step comprising fusing by hot pressing two plastic layers making up the card bodies onto the even faces of said plasticised antenna support.