Patent ID: 7419112

Claim:
A refining surface of a refining member adapted for use with a refiner for defibrating a lignocellulose-containing material, the refiner comprising at least two adjacently-disposed refining members arranged coaxially relative to each other along an axis, wherein at least one of the refining members is configured to rotate in a rotational direction about a shaft arranged along the axis, and the at least two refining members are configured to receive the lignocellulose-containing material in a refining gap therebetween, the refining gap defining a refining plane, such that the material is defibrated by the respective refining surface of each refining member within the refining gap, the refining surface of the refining member parallel to the refining plane comprising: a plurality of first bar portions defining first grooves between adjacent first bar portions, each first groove having a bottom surface, each first bar portion extending between opposing first and second radial edges of the refining surface and having a leading surface, an opposed trailing surface, each with respect to the rotational direction, and an upper surface, each of the leading and trailing surfaces being configured to extend away from the bottom surfaces of the respective first grooves such that the upper surface of each first bar portion is substantially planar and parallel to the refining plane; and the upper surface of each first bar portion having a plurality of second bar portions defining second grooves between adjacent second bar portions, each second bar portion extending between two adjacent first grooves, the first bar portions being wider than the second bar portions, and each second bar portion being between about 1 mm and about 3 mm wide.