Polymeric preform for a blow molded plastic article
A polymeric preform that can be blow molded into a plastic article includes an open neck portion, a body portion with a sidewall, and a closed end opposite the neck portion with a thickness of not more than 70 percent of the thickness of the sidewall. The thickness of the closed end is preferably in the range of 30 percent to 70 percent of the thickness of the sidewall, and more preferably between 30 percent to 50 percent of the sidewall thickness. This reduces the volume or amount of material needed to form the preform without adversely impacting the structural integrity or physical properties of a container formed from the preform. According to one presently preferred aspect of the invention, the preform is compression molded.
1 . A method of making a preform for blow molding a plastic container, which includes compression molding a preform to have an open neck portion, a body portion with a sidewall and a closed end with a thickness of not more than 70% of the thickness of said sidewall.
2 . The method set forth in claim 1 wherein the thickness of the closed end is in the range of 30% to 70% of the thickness of the sidewall.
3 . The method set forth in claim 2 wherein the thickness of the closed end is in the range of 30% to 50% of the thickness of the sidewall.
4 . The method set forth in claim 1 wherein the sidewall has a non-uniform thickness along its axial extent and thickness of the closed end is in the range of 30% to 70% of the thickest portion of the sidewall.
5 . The method set forth in claim 4 wherein the thickness of the closed end is in the range of 30% to 50% of the thickest portion of the sidewall.
6 . A polymeric preform that can be blow molded into a plastic article includes a body having a sidewall, an open end and a closed end at an end of the sidewall opposite to the open end, the thickness of the closed end being not more than 70% of the thickness of the sidewall.
7 . The preform set forth in claim 6 wherein the thickness of the closed end is in the range of 30% to 70% of the thickness of the sidewall.
8 . The preform set forth in claim 7 wherein the thickness of the closed end is in the range of 30% to 50% of the thickness of the sidewall.
9 . The preform set forth in claim 6 wherein the sidewall has a non-uniform thickness along its axial extent and thickness of the closed end is in the range of 30% to 70% of the thickest portion of the sidewall.
10 . The preform set forth in claim 9 wherein the thickness of the closed end is in the range of 30% to 50% of the average thickness of the sidewall.
11 . A compression molded preform as set forth in claim 6 .
12 . The preform set forth in claim 6 wherein the thickness of the sidewall is between 2.5 and 5 millimeters.
13 . The preform of claim 12 wherein the thickness of the closed end is between 0.75 and 3.5 millimeters.
14 . The preform set forth in claim 6 wherein the thickness of the sidewall is between 3 and 4 millimeters.
15 . The preform of claim 14 wherein the thickness of the closed end is between 0.9 and 2.8 millimeters.