A process for preparing a polyurethane containing composite element by means of vacuum technology

Mold for producing composite elements comprising a bottom mold part (3) and an upper mold part (4), a first sealing circle (1) and a second sealing circle (2), wherein a mold cavity (5) is formed in the closed state of the mold caused by the circumferential first sealing circle (1) is limited and wherein circumferentially limited by the through the first sealing circle (1) mold cavity (5) has an evacuable vacuum space (6) is formed, which is delimited by the first sealing circle (1) and second sealing circle (2) ,