Finnish packaging provider Walki Wisa has developed a new wafer material called WalkiLid, which dairy producer Valio has now switched to.
The material was developed by laminating paper with several different polymer layers. This process has created a reinforced material which the company claims is strong, tough and provides a good seal.
"Despite this, the lid is easier to open than traditional lid material," said Antti Viitala, Walki Wisa's marketing manager.
The company also claims that the WalkiLid can be used for many different kinds of dairy and food products, such as yoghurt, ice cream, quark, salads, marmalade, sweets and treacle.
Following several years' development work, WalkiLid is now a finished product, according to its manufacturer, a view which is confirmed by Valio: "We've played an active part in the development work and, in our view, WalkiLid works perfectly on the later models of packaging machines we have adopted," said development manager Leo Junkkarinen.
Valio already uses WalkiLid at several of its dairies as lid material for sour milk, yoghurt, cottage cheese and smetana. At its dairy plant in Kouvola, Finland, the material is used for production of all low-fat sour milk, while at the company's other dairies it currently accounts for only part of production.
"A paper-based lid material is more sensitive than aluminium to temperature changes during heat sealing. We are therefore going over to paper lids as we modernise or renew our machines," Junkkarinen explained.
Environmental reasons also lie behind Valio's decision to go over to a new lid material.
"The gradual phasing out of the use of aluminium is clearly in tune with the spirit of our environmental programme," said development manager Leo Junkkarinen.
But there are also many user-related and marketing reasons in favour of a change.
"WalkiLid has better printability and enables us to produce more attractive and informative packaging," pointed out Pirjo Huhtala, Valio's marketing manager.
From the customer's point of view, it is also a clear advantage to have a lid material which is more durable, more resistant to being punctured and easier to open.
"With WalkiLid there's no risk of cutting your hands," said Junkkarinen, referring to his own experience of handling dairy products in a catering environment.
Walki Wisa, a UPM-Kymmene unit, specialises in paper-based packaging materials. Its biggest customers are the paper, board, steel and insulating material industries. Walki Wisa has a turnover of approximately €300 million and some 1,000 employees. Total production capacity is around 300,000 tonnes per year and all of its factories are ISO 9000-certified.