Edited by Cori Watkins, contributing editor, Plastics Decorating

Summer is here, and there is something universally refreshing about enjoying an ice-cold beverage while kicking back, relaxing and cooling down. Ren-Flex Packaging (Ren-Flex), based in Johannesburg, South Africa, had just this scene in mind when creating its visually striking cooler boxes that featured a large, digitally printed in-mold label, providing a branded keepsake that captivated the local community and sports fans worldwide with its customized designs. Ren-Flex was honored with the Judges’ Choice Award for these uniquely themed, durable cooler boxes in the 2024 IMDA Awards Competition.

Ren-Flex has delighted its customers by providing individualized cooler boxes that could be customized for local events, corporate branding, sports teams and more. Four of the boxes submitted for the awards competition included:

• South African Flag. Promoted at the largest country-wide supermarket group after success in sports, raising the South African patriotism rankings.
• Springbok. Featuring South Africa’s rugby team, which has won the most World Cup trophies since the inception of the tournament in 1987.
• Community Golf Day. Sending each golfer at a local event home with a prize to keep the drinks cool while golfers enjoyed a fun-filled day.

Big Label, Bigger Impact
Ren-Flex’s molding partner PENFLEX introduced the company to the idea of a large-format label, recognizing that Ren-Flex possessed the advanced printing and diecutting capabilities necessary to successfully produce such a product. By handling every aspect of the project in-house, Ren-Flex ensured a truly unique and local supply and manufacturing process.

The in-mold label (IML) film first was digitally printed on a 760 mm x 1,100 mm web using an HP25000 digital press, whereby consecutive labels could differ in artwork. The CMYK inks ensured vivid, high-quality graphics. After printing the labels, the Schober rotary diecutting machine was used to precisely cut three cooler box labels per frame, with a die size of 960 mm x 740 mm. This is a very large label that is required to lay flat once inserted into the molding machine label cassette.

For a textured, durable finish, the high-density IML film was laminated after printing with a variety of biaxially oriented polypropylene (BOPP) clear substrates. This lamination step was performed on a SEN solventless laminator. The film preparation, curing and lamination process was critical throughout all stages to ensure ink adhesion, lamination tension and final result after diecutting. The transparent lamination protected the printed IML film from scratches and abrasions and presented a lush, gloss finish.

In addition to the large label size – the 944 mm x 253 mm label was designed to cover all four panels of the cooler box with one continuous graphic – each corner presented a degree change as the cooler box was designed with a taper from bottom to top. The exact placement of the label was crucial as the gap size of “label joint” at the side of the cooler box was managed by the label position in the mold, as well as by monitoring the mold temperature to minimize the shrink of the label.

While the cooler boxes were a swimming success, there were a few hiccups in the initial stages of the construction process when the design presented challenges. Achieving precise alignment of the artwork across the entire label was critical during the diecutting process, ensuring that the graphics remained perfectly positioned and were not skewed when molding. Additionally, the lamination process caused the labels to curl, creating complications for the molding robotics during label delivery to the mold. To address these issues, Ren-Flex developed a specialized set of lamination parameters to maintain label flatness during packing, ensuring seamless integration into the production process.

Why IML?
The production goal for the cooler boxes was to print as many label variants as possible with the least quantity accounted for each variant, in an effort to flood retail markets with variety and style. In-mold labeling provided a perfect solution as the labels could be switched out for each individual cooler box style without changing other production parameters.

The durability of the IML also was important, as the cooler box would be roughly handled throughout all of its different applications and uses. Ren-Flex did not want the artwork to be damaged during usage. And, with the coolers storing and transporting ice and cold beverages in outdoor settings where heat would create condensation on the outside of the cooler box, the IML with transparent lamination protected the cooler branding from water damage.

New Designs on Tap
The Ren-Flex cooler box is a keepsake that will last well and will be shared by many at BBQs, beach parties and sports gatherings. Customers across all purchasing entities love the appearance and quality of the popular cooler boxes. Monthly orders have become necessary to accommodate the increase in sales and changing marketing trends, and more than 100 different designs have been manufactured to date, with different quantities for each.

Building on the success of the current designs and box colors, trials are being conducted for a metallic look, soft-touch feel and transparent features to allow the cooler box’s molded resin color to be revealed through the label. These exciting new designs will be available soon. Additionally, brands will have the opportunity to create and feature variable artwork across their product ranges on Ren-Flex cooler boxes, allowing the recipients to load their Ren-Flex cooler boxes with all of their favorite refreshments, chill out and savor the lingering summer heat in ultimate style!