Method for producing a toothbrush handle having an inner cavity

A toothbrush handle produced by a method comprising:

• a) providing an extrusion blow mold having a longitudinal axis and a cavity, the cavity having a surface that defines a cross-sectional area;
• wherein the cavity has at least one of a maximum cross-sectional area, bordered by two smaller cross-sectional areas along the longitudinal axis of the blow mold or a minimum cross sectional area bordered by two greater cross-sectional areas along the longitudinal axis of the blow mold;
• b) extruding a parison comprising a first thermoplastic material and a second thermoplastic material, the parison includes an interior cavity and an outer surface, wherein the outer surface defines a cross-sectional area of the parison;
• c) expanding the parison using a fluid to contact the cavity surface and produce a toothbrush handle having an inner cavity;
• and
• the toothbrush handle comprising:
• d) a terminal end, connector end, outer surface, inner cavity, and longitudinal axis;
• e) the inner cavity having a surface defining a cross-sectional area;
• wherein the inner cavity has at least one of a greater cross-sectional area, bordered by two lesser cross-sectional areas along the longitudinal axis of the toothbrush or a lesser cross sectional area bordered by two greater cross-sectional areas along the longitudinal axis of the toothbrush;
• f) the outer surface defining an outer surface cross-sectional area;
• g) a wall formed from the outer surface and inner cavity surface;
• h) the toothbrush handle comprising a single unitary component;
• and
• wherein the toothbrush handle has a specific gravity below about 0.60 g/cm3 and
• wherein the toothbrush handle deforms less than about 10 mm under a 5.0N force applied as determined by ASTM D 790.