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\u2019s 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\u2019s 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\u2019s 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\u2019Brien: Save the gable-top carton. He didn\u2019t 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\u2019s 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. That design met the team\u2019s manufacturing goals. Since the patch was only a couple of millimeters thick, it could be attached to cartons in IP\u2019s factories. The cartons could be shipped flat, assembled and run through a dairy or juice maker\u2019s fill line with little disruption. While the rest of the divisional board was lukewarm on the project, the team came armed with enough positive focus group feedback and had addressed the manufacturing concerns adequately enough to secure funding for a test rollout of the new package design. By 1987, the Pachin-Pak was ready for test marketing in Japan.Market CapThe original goal of the market test was to move a million cartons the first month. "We sold 10 at least," Thoman says. The rest sat on the shelves. "We thought the Pachin-Pak would be a showstopper because it was very inexpensive," Kalberer says. They were wrong. After a year of extensive interviews with food packagers and reading customer surveys, the message was brutally clear. "They all said it was a good idea, but give me the whole screw cap so I can shake it," Thoman says. Consumers also said they would pay extra for such a device. While that may seem obvious in retrospect, it was a revelation to a commodity company servicing a commodity industry. The initial feedback from juice and dairy packagers had been that innovation was acceptable only if the cost was minimal. IP\u2019s customer data challenged that basic notion. The development group immediately rekindled an idea that had been dismissed earlier because of cost?an injection-molded screw cap glued to the side of the carton. The concept was an immediate success in focus groups. "We literally had people jump up and down," says Thoman. After a three-month investigation of more than a dozen potential spout makers, Gordon approached West Pharmaceutical Services (formerly West Co.), a Lionville, Pa.-based manufacturer that already made the appropriate-size caps (a built-in cost savings) and required the same sterile environment as beverage packaging. One major manufacturing issue remained unresolved. Since late 1988, Kalberer and Mike Trask, gable-top product manager for filling-equipment manufacturer Cherry Burrell in Cedar Rapids, Iowa, had been trying to determine how to attach a plastic spout to a paper carton, then how to retrofit existing filling equipment. After much trial and error, Kalberer attached the spout with ultrasonic vibrations that converted electrical energy into mechanical energy in a fraction of a second. Trask describes it less technically as "mashing up the molecules of the coating and the plastic and welding them together."That was the easy part. The existing 20-foot-by-7-foot filling machines formed the bottom, applied the spout closure, filled the carton with product and sealed the top. Each machine filled 100 to 140 cartons per minute. Kalberer and Trask had to add the fourth step of attaching the plastic spout without diminishing line speed. However, the final cost of the retrofit was high?about one-third to one-half the original cost of the machines. Still Changing By the end of 1990, the first Spout-Pak cartons hit supermarket shelves. It was an immediate success. Right away, new orders came in from companies that had initially resisted the idea. In 1991, IP bought the packaging equipment division of Cherry Burrell, renaming it Evergreen Packaging Equipment. Bringing a product to market is only the start, Kalberer says. As other companies design plastic spout solutions, IP must continue to innovate. The purchase of Evergreen helped, as IP is the only carton manufacturer that owns filling machinery. The product continues to evolve as well. Throughout the 1990s, IP introduced different size containers to complement the original half-gallon size. In 1995, it attached the spout closure to the inside of the carton instead of the top, producing a better seal and allowing the juice inside to be pasteurized at a higher temperature for better freshness. In 1997, a plastic pull-ring replaced the original foil cover for an easier-to-open carton.With each of these upgrades, says Kalberer, engineering teams found ways to eliminate equipment retrofitting costs. While the Spout-Pak has revitalized gable-top sales, the paper carton is still losing ground to the plastic container, albeit at a much slower rate. The biggest reason is the dairy market. Most organic and soy milk producers have turned to the Spout-Pak, but dairies still see milk as a price-only commodity. IP\u2019s next challenge is to market the Spout-Pak to dairies. The company is championing a dairy spout called the Fresh-Cap, although Product Manager Chris Reilly admits it is essentially the same product with a different name.The Spout-Pak is helped by inroads it made in the market 10 years ago, Kalberer says, but is still succeeding only because "we continue to look at what features are important and for attributes that simplify or enhance the manufacturing process."