Alpha Packaging has recently introduced four 32-ounce narrow-neck bottles that are made using a 2-stage blow moulding process. Each of the new 32-ounce bottles represent the largest size in Alpha’s four most popular polyethylene terephthalate (PET) liquid lines: Boston Rounds, Cosmo Rounds, Modern Rounds and Capri Ovals.
These bottles are typically used for large quantities of hand sanitizers, liquid soaps, shampoos and conditioners, and other liquids used around the home or in larger institutional settings. The overflow for each bottle exceeds 1000ml (1 litre), so they are ideal for items marketed as either 32 liquid ounces or litre-size.
All four bottles are made from the same 50-gram, 28-410 pre-forms on 2-stage (reheat and blow) machinery at Alpha’s Salt Lake City plant. Reheat and blow is a stretch blow moulding process in which a plastic pre-form is injection moulded in one process, and then at a later time, that pre-form is fed into a machine, reheated, and stretch blow moulded in a second step. Often, pre-forms are made by one company and purchased by another company to make the finished bottle. However, in the case of these 50-gram pre-forms, Alpha manufactures both the pre-form and the bottles in its 2-stage process.
Alpha’s 50-gram pre-forms are available in standard colours of clear, light amber, cobalt blue and white for any of the four styles of narrow-neck bottles. Minimums for coloured bottles are 50,000 pieces; clear bottles have a one-pallet minimum.
The 2-stage process has several advantages over Alpha’s usual single-stage injection stretch blow moulding (ISBM) process, especially for the larger bottles Alpha is using it for. According to Bob Wilson, Director of Alpha Technology Centre, “The 2-stage stretch blow moulding process offers the ability to produce fairly lightweight containers with very high impact resistance, which is ideal for these large PET bottles,” he says.
The bottles are featured in Alpha's online catalogue as well as in their WEBpackaging catalogue, in the PET Narrow Neck Bottles" section.