Imagine a thin plastic container with moisture and oxygen barrier capabilities that is printed flat with high-quality flexo and litho printing. Paper Machinery Corporation, the world's leading source of forming machines for paper cups and paperboard packages, is refining the substrates used in the first ever convolute pre-printed plastic container forming machines using PMC's exclusive Barrier Plus™ technology.
The first commercial application of Barrier Plus technology was developed in collaboration with ProCal, a manufacturing company based in South Gate, CA. ProCal was searching for an innovative solution to differentiate their PicturePot containers within the garden and nursery market.
According to Gary Vollers, ProCal's president: "The difference between the Barrier Plus technology and our old manufacturing process is comparable to the performance of a Model T versus a Ferrari. Assembling the quality, pre-printed pots from a flat sheet has enabled us to reach the highest production rate with the best product in our 20-year history."
ProCal is using the high quality graphics produced by Barrier Plus technology to build brand recognition among competitive products merchandised by large all-purpose retailers. "Customer response to the new containers has been unbelievably positive, and the feedback tells us that our pots are better than anything else on the market," said Vollers. "Since replacing our equipment and upgrading technology to Barrier Plus, we've significantly increased production with the same number of employees."
Widening the scope
Paper Machinery is refining the technology to achieve several more objectives. Normal polypropylene becomes brittle when exposed to the sub-freezing temperatures usually encountered when packaging ice cream, but Barrier Plus has gotten over that hurdle. They have also achieved a sufficient moisture barrier for most applications, and the company believes that their ability to produce a formidable oxygen barrier and a flat rim will open up many opportunities.
"Until Barrier Plus, printing, die-cutting and convolute forming of preprinted polypropylene has not been achievable," said Jerry Meier, vice president of PMC. "Modifying the polypropylene material was necessary for what has traditionally been achievable on PMC machinery with polyethylene-coated paperboard."
The difference with Barrier Plus is that printing is done on polypropylene sidewall blanks, prior to forming, to produce richer and more saturated colors and sharper images. The new Barrier Plus machinery then replicates the sequence of operations that go into making two-piece paperboard cups. The sidewalls are totally sealed, the rims are tucked-and-rolled and the bottoms are 360* double-sealed.
The plastic sheet is considerably thinner than the sheet used for thermoforming. It has significant amounts of minerals added which also reduces the plastic cost. At a production speed of 225 containers per minute, the PMC forming machine produces containers more economically and utilizes less costly tooling than other forms of plastic technology.
Since ProCal pots are used to grow and transport plants, as well as maintain their presentation for retail, an attractive capability of Barrier Plus was the option of punching holes into the sidewall and bottom. Picture Pots feature quality graphic reproduction with easy-to-read, easy-to-find information. This strengthens the communication throughout the grower-to-retail cycle. Growers know which pots to use, merchants know whether to display in sun or shade, and consumers know the description of the plants purchased, eliminating the bothersome little sticks or plastic tags.