| 摘要 |
A multiple layer sheet structure (10) suitable for making tubular squeeze containers, such as for dentifrice, incorporates a uniaxially oriented polypropylene layer (16) within 1.5 mils (0.038 mm) of a surface of the structure destined to be the exterior of the container. Preferably the polypropylene is coextruded with low density polyethylene (12), and an intervening adhesive polymer (14) to form a three layer coextruded film substructure. The substructure is then uniaxially oriented at a stretch ratio of 3/1 to 4/1 and then laminated to the other layers (18 to 30) of the multiple layer structure, the low density polyethylene layer (12) forming one of the exterior surfaces of the sheet structure. Lap-seamed tubes are formed from the sheet structure with the uniaxially oriented layers (12 to 16) at the outer surface of the tube, and with the direction or orientation running along the length of the tube. |
