Patent ID: 8012283

Claim:
A method for producing a fiber-reinforced resin composition comprising: supplying a plurality of fiber bundles into an enclosed space having a box-shape within an impregnation chamber, in which enclosed space having a box-shape threshold plates are provided, some of the plurality of fiber bundles passing between the threshold plates along at least part of longitudinal sides of the impregnation chamber; supplying a molten thermoplastic resin from a plurality of resin flow inlets into the enclosed space, the plurality of resin flow inlets being almost symmetrically positioned relative to the direction of progress of the fiber bundles on opposing faces of the impregnation chamber, so that the pressure of resin flow from the resin flow inlets of one opposed face is almost the same as the pressure of resin flow from the resin flow inlets of the other opposed face; contacting the molten thermoplastic resin with the fiber bundles in the impregnation chamber to impregnate the fiber bundles with the molten thermoplastic resin; and withdrawing the fiber bundles impregnated with the molten thermoplastic resin from the impregnation chamber.