SLEEVE MOLDING

SLEEVE MOLDING APPARATUS AND METHODS OF MAKING MULTILAYER INJECTION MOLDED PLASTIC ARTICLES IN SUCCESSIVE MOLD CAVITIES. IN A FIRST MOLDING STEP, AN INNER SLEEVE (20) IS MOLDED ON A CORE (9) IN A FIRST MOLD CAVITY (11), WHICH MAY COMPRISE A FULL BODY LENGTH SLEEVE OR ONLY A PARTIAL SLEEVE, SUCH AS AN UPPER NECK FINISH PORTION. THE SLEEVE AND CORE ARE WITHDRAWN FROM THE FIRST MOLD CAVITY WHILE THE SLEEVE IS STILL WARM, AND TRANSFERRED WITHOUT SUBSTANTIAL DELAY TO A SECOND MOLD CAVITY (12) FOR INJECTION MOLDING AN OUTER LAYER (22) WHICH BONDS TO THE INNER SLEEVE. BY TRANSFERRING THE SLEEVE (20) AT AN ELEVATED TEMPERATURE INTO THE SECOND MOLD CAVITY (12), AN IMPROVED BOND IS FORMED BETWEEN THE INNER SLEEVE AND OUTER LAYER WHICH RESISTS SEPARATION DURING A LATER REHEAT STRETCH BLOW MOLDING STEP, AND/OR IN USE OF THE RESULTING ARTICLE. IN A PREFERRED EMBODIMENT, A PASTEURIZABLE BEER CONTAINER IS PROVIDED HAVING A FINISH-ONLY SLEEVE (250) OF A PEN POLYMER. IN A SECOND EMBODIMENT, A RETURNABLE AND REFILLABLE WATER CONTAINER IS PROVIDED HAVING A FULL-LENGTH BODY SLEEVE (120) OF A PEN POLYMER. A MULTI-STATION INJECTION MOLDING APPARATUS IS PROVIDED HAVING A TRANSFER MECHANISM, SUCH AS A ROTATABLE TURRET (2) OR RECIPROCATION SHUTTLE, FOR COST-EFFECTIVE MANUFACTURE OF PREFORMS SIMULTANEOUSLY IN MULTIPLE CAVITY SETS.