Patent ID: 7582238
Filing Date: 2009-09-01
Classification: B29C,B63B

Abstract:
1. A method of forming a surfboard using a two-shot rotational molding process comprising: adding a first polyethylene material into a mold, said mold having one or more ventilation holes located therein; heating the first polyethylene material in the mold while rotating the mold for a pre-determined period of time and at a predetermined temperature to form a skin, said first polyethylene material being in a form comprising at least a powder form, wherein the first polyethylene material forms the skin as substantially solid without any substantial air voids; adding a polyethylene mixture into the mold, wherein the polyethylene mixture comprises a blend of a second polyethylene material and a foaming agent, said second polyethylene material being in a form comprising at least a pellet form and/or a micropellet form, wherein the second polyethylene material is the same as the first polyethylene material; and heating the polyethylene mixture inside the mold while rotating the mold for a pre-determined period of time and at a predetermined temperature to form a foam core; and cooling said mold for a predetermined amount of time wherein either a main body of a surfboard or an entire surfboard is then formed, and wherein the foam core transitions from the skin as a single unit with the skin and made of the same polyethylene material.