Filament for an oral care implement and oral care implement

A filament for an oral care implement has a longitudinal axis and a substantially cross-shaped cross-sectional area extending in a plane substantially perpendicular to the longitudinal axis. The cross-shaped cross-sectional area has four projections and four channels. The projections and channels are arranged in an alternating manner. Each channel has a concave curvature formed by neighboring and converging projections. The concave curvature has a radius, and each projection is end-rounded thereby forming a curvature. The curvature has a diameter, and the ratio of the diameter of the curvature of the projection to the radius of the curvature of the channel is from about 0.2 to about 1.5. (Fig. 2) 28 ---42 46 Fig. 2