Patent ID: 8689513

Claim:
Floor covering comprising panels, each panel comprising: a core of polyurethane, said core comprising filling materials, a glass fiber mat provided in an upper portion of a center of the core and extending horizontally through the core, two cover layers on an upper side of the core, comprised of: an upper wear layer made of a wear resistant transparent plastic material, and a décor layer beneath the wear layer formed by a printed décor film, complementary and mutually engaging locking profiles at connected lateral edges thereof, the lateral edge of one of said locking profiles including a lower protrusion that comprises a trough-shaped receiving portion on an upper side thereof, said receiving portion having a generally trapezoid shaped cross-section and being delimited towards an end of the protrusion by an elevated portion, and above the receiving portion, an upper lateral edge portion being generally vertical and comprising a flexible detent that is angled relative to vertical, the lateral edge of the other locking profile being provided with a protrusion facing in a downward direction at the lateral edge thereof adapted to be received within the receiving portion of the one said locking profile by being depressed in a vertical direction into the receiving portion, the other said locking profile including a depression shaped complementary to said angled flexible detent for engagement therewith, wherein at least one of said panels includes a milled-out portion at an upper side of a lateral edge thereof, with the cover layers thereat being excavated completely over a width of the milled-out portion so that a bottom of the milled-out portion is formed by the material of the core, such that a groove with a rectangular cross section and approximately vertical sidewalls is formed between the two said connected panels, being delimited laterally by the sidewalls of upper edges of the said connected panels.