Picture a kid eating his school lunch or a lazy bachelor at the refrigerator. The tear-and-fold paper carton is inseparable from these images, whether it’s a child washing down tater-tots or a grown man drinking straight out of the container. Yet for a while, the gable-top container, like the slide-rule and eight-track tape, seemed destined for Americana?a product from an earlier time. Why? To quote The Graduate, "One word: plastics."

By the mid-1980s, plastic milk and juice bottles were steadily taking market share from their paper cousins. Stamford, Conn.-based International Paper (IP), one of the country’s leading paper carton manufacturers, knew it had to fight to save one of its core products from extinction. The now-ubiquitous Spout-Pak, the official moniker for that little plastic screw cap on the side of juice carton tops, was the result of that fight.

The Spout-Pak has been successful beyond IP’s wildest dreams. When the development team first pitched the idea in 1986, it projected annual sales of 50 million Spout-Pak cartons. Today, IP sells approximately 2 billion every year. Still, the development process was humbling. The team overcame initial failures, internal strife and reluctant customers. The company succeeded because it kept customer needs and manufacturing realities in mind, and most important, it accepted the lessons the market taught it along the way.

Endangered Species

Research Scientist Rod Kalberer had been at IP less than a year in 1985 when his marching orders came down from Vice President of Liquid Packaging Division Jack O’Brien: Save the gable-top carton. He didn’t receive much more direction than that.

Kalberer teamed up with two other R&D men?Bruce Thoman and the since-retired Bob Gordon. Their charge was to reverse the decade-long trend of decreasing gable-top container sales.

Despite the paper carton slump, IP was still the market leader simply because gable-top production and packaging equipment had been in place for decades and beverage packagers were loath to spend money on alterations. This gave the IP development team both an opportunity and its first project parameter: Any changes had to be cheap. "Finding a solution that you can also manufacture is the biggest challenge," says Kalberer. Ninety percent of any manufacturing changes would have to happen in IP’s factories so as not to slow down the filling process in dairies and juice plants.

Gordon sought inspiration in niche packaging markets throughout Europe and Asia. He found that some high-end Japanese sake packagers were augmenting paper containers with plastic opening devices. Over the next year, Kalberer and Gordon developed a plastic opening tab they could attach to the side of the traditional paper gable-top carton.