K3® – cardboard-plastic combinations

With our cardboard-plastic combinations, called K3® packaging, a cardboard wrap is applied to plastic packaging – such as a cup, tub, or bottle. K3® is becoming an increasingly popular packaging solution, and rightly so. After all, this packaging is not only convenient and features an appealing look – its sustainability characteristics are extremely attractive, too.

Sustainable materials

The materials used (unprinted PP cup and cardboard) are 100% recyclable when separated and disposed of by the consumer. If necessary, the cardboard wrap can be made from recycled cardboard or even grass paper. Greiner Packaging will use r-PET or r-PO for its packaging as soon as these materials are approved for food applications. Cardboard-plastic combinations perform extremely well when taking the entire life cycle of packaging into consideration in general: They require 32.7% less plastic material, use up to 80% recycled cardboard, and have a 17% better carbon footprint than packaging made entirely of plastic (reference value: cup – 95 mm diameter, 500 ml filling volume, direct printed, thermoformed).

Easy recyclability

Greiner Packaging makes ongoing improvements to its cardboard-plastic combinations in order to help consumers separate the cardboard and plastic correctly.

In developing K3® r100, Greiner Packaging has created a solution in which the cardboard wrap separates itself from the plastic cup during the waste collection process. This means that the cardboard and plastic can be assigned to the correct material streams during the initial sorting process before being recycled.

However, the best-case scenario is for the consumer to separate the cardboard wrap from the plastic cup and dispose of the parts properly, thereby ensuring that the cup and wrap are directed into the correct recycling streams. To make this separation process even easier and more intuitive for consumers, Greiner Packaging teamed up with Offsetdruckerei Schwarzach to develop a new tear-off system. If the wrap and cup still aren’t properly separated, the latest technologies such as digital watermarks can ensure that the individual components of the cup are correctly detected in the waste sorting plant and assigned to the appropriate recycling stream.

Look & Feel

  • Enhanced shelf impact: K3® cups attract attention! The cardboard wrap signifies a completely new approach to food packaging—an approach that will set you apart from your competitors.
  • Unique shapes and designs: Full-cup coverage and a wrap that can be printed with up to six (6) colors on both sides, delivering full 360° design capability.
  • Aluminum lamination, embossing and hot-stamping possibilities: Add a premium look and feel to your products.
  • An elegant, inviting feel: Thanks to the cardboard wrap, K3® cups are comfortable to hold and add a premium ecological touch to your packaging.
  • Enhanced insulating properties: Burnt fingers are now a thing of the past. The cardboard wrap provides a particularly pleasant feel—even if the cup contains hot content.
  • Multipacks: K3® cups are also available as multipacks

Consumer Engagement

  • Maximized marketing opportunities: Engage your customers with stickers or promotions on the inside of the cardboard wrap, display printed (children’s) games and additional product information, or even trigger the purchase impulse with printed instant win codes on the wrap’s interior. High-quality printing methods allow for sophisticated design variations.
  • Windowed and shortened wraps for increased product visibility: Give your customers a peek at what’s inside.
  • Microwaveable and freezable: K3® cups meet your customers’ demands for convenience and are easily integrated into their daily routine.


  • Reduced CO2 emissions thanks to reduced plastic content: Compared to conventional packaging, the cup’s plastic content can be decreased by up to 50%, which significantly contributes to lowering CO2 emissions during production.
  • High stability thanks to cardboard wrap: Even with a reduced plastic content, the cardboard wrap secures high stability of the cup.
  • Responsible resource consumption: Reduced plastic content combined with the use of many renewable raw materials such as recycled cardboard and virgin fiber-based cardboard. 100% protection from light when using recycled cardboard.
  • Easy separation of cardboard and plastic: The two components can be easily separated from one another thanks to perforations in the cardboard wrap. In the case of K3® r100, the components are even able to separate from each other independently on the way to the sorting system.
  • Barrier properties: With barrier technologies, Greiner Packaging has succeeded in bringing food shelf life for cups to a whole new level.

Related articles