Stretch rod for a stretch blow molding machine
View Patent ↗A multilayer plastic container comprises a layer of a polypropylene and an intermediate layer directly adjacent the layer of polypropylene wherein at least one of the polypropylene and intermediate layers comprises an adhesive such as maleic anhydride incorporated therein to adhere the layer of polypropylene to the layer of EVOH.
1. A stretch blow molding stretchrod comprising an elongated rod and a tip fixed to the end of the elongated rod, the tip defining a backside and an arcuate stretching surface for engaging a preform, the backside comprising a surface variation to increase the surface area of the tip backside.
2. A stretch blow molding stretchrod comprising an elongated rod portion and a tip portion located at an end of the elongated rod portion, the tip portion defining a backside and an arcuate stretching surface for engaging a preform, the backside of the tip portion comprising surface variations.
3. The stretchrod of claim 2 , the surface variations comprising at least one hole defined by the tip portion backside.
4. The stretchrod of claim 2 , the surface variations comprising at least one groove defined by the tip portion backside.
5. The stretchrod of claim 2 , the surface variations comprising at least one fin extending from the tip portion backside.
6. The stretchrod of claim 2 , wherein the stretchrod is comprised of aluminum.
7. A stretch blow molding stretchrod comprising an elongated rod portion and a tip portion located at an end of the elongated rod portion, the tip portion defining a backside and an arcuate stretching surface for engaging a preform, the tip backside having surface variations, and the arcuate stretching surface having a diameter and the rod portion have a diameter, the diameter of the arcuate stretching surface being greater than the diameter of the rod portion.
8. The stretchrod of claim 7 , wherein the surface variations comprise at least one hole defined by the tip portion backside.
9. The stretchrod of claim 7 , wherein the surface variations comprise at least one groove defined by the tip portion backside.
10. The stretchrod of claim 7 , wherein the surface variations comprise at least one fin extending from the tip portion backside.
11. A stretch blow molding apparatus for blow molding preforms, the stretch blow molding apparatus comprising a stretchrod comprising an elongated rod portion and a tip portion located at an end of the elongated rod portion, the tip portion defining a backside and an arcuate stretching surface for engaging a preform, the backside of the tip portion comprising surface variations.
12. The stretchrod of claim 11 wherein the surface variations comprise at least one hole defined by the tip portion backside.
13. The stretchrod of claim 11 , wherein the surface variations comprise at least one groove defined by the tip portion backside.
14. The stretchrod of claim 11 , wherein the surface variations comprise at least one fin extending from the tip portion backside.
15. The stretchrod of claim 11 , wherein the stretchrod is comprised of aluminum.