To provide a recording liquid feed path, recording liquid container, and recording liquid feed device having the same, as well surface modifying method for the recording liquid feed device to feed efficiently a recording liquid for ejection through a feed tube. If the interior of the feed tube is not rendered hydrophilic as shown in FIG. 3A, air which has passed through a wall of the feed tube forms a bubble, which bubble adheres to an inner surface of the feed tube and obstructs a flow of the recording liquid. But if the inner surface of the feed tube is rendered hydrophilic to form a hydrophilic surface as shown in FIG. 3B, the recording liquid is conducted along the hydrophilic surface at the inner surface portion of the feed tube with the bubble adhered thereto, so that the adhesion area of the bubble to the feed tube inner surface is reduced and the bubble floats from the inner surface. Consequently, when the recording liquid is fed, the bubble can be removed easily by the flow of the recording liquid and thus the flow of the recording liquid can be prevented from being obstructed by the bubble.