Shoe press belt

A shoe press belt which is an independent piece with a shape of an endless loop, runnable in a shoe press through a long nip between at least one roll and a press shoe, the shoe press belt comprising:

• a base which is of an elastomeric heat-resistant material;
• a plurality of polymeric support yarns arranged in at least one yarn layer inside the base;
• and
• a first surface on the side of the press shoe, and a second surface on the side of a fibre web,
• wherein at least some of the support yarns are heat-resistant polymer yarns, the polymer structure of the material of which comprises a naphthalene group,
• wherein the structure of said heat-resistant polymer yarn comprises completely aromatic liquid crystalline polymer, the completely aromatic liquid crystalline polymer being poly(4-hydroxybenzoic acid-co-6-hydroxy-2-naphthoic acid) and the glass transition temperature Tg of said polymer material is at least 110° C.,
• wherein the shoe press belt is impermeable, and
• wherein the force required for a 2-% stretch of said heat-resistant polymer yarn is at least 10 cN/tex, 20° C.