When he visited Niigata University of Pharmacy and Applied Life Sciences in the city of Niigata in 2017, researcher Yusuke Suga of Dai Nippon Printing Co., Ltd. (DNP) was wondering what need a university had for a new type of stylish plastic bottle covered with a functional film that he and his research partner developed.
The High Pressure Sterilized Draft Sake Consortium, led by the university, had just developed a revolutionary brewing technology to apply high pressure - not the conventional method of using heat - to deactivate microorganisms such as yeasts in draft sake to retain its fresh and elegant flavor and allow it to be transported at room temperature. The consortium’s demonstration project was aimed at promoting overseas exports of draft sake at a time when Niigata Prefecture, one of Japan’s rice-producing centers, has been stung by declining domestic rice and sake consumption. If draft sake can be shipped overseas without its taste being compromised, it will potentially fetch premium prices among overseas consumers.
One major stumbling block, however, lay with the sake’s bottle. When subjected to high pressure, glass and can containers break or deform. Professor Toru Shigematsu of the consortium considered using polyethylene terephthalate (PET) bottles, but these bottles do not usually conjure up impressions of high-end beverages. Shigematsu became interested in Suga’s PET bottle after being informed about it by a DNP salesperson in Niigata.
“Professor Shigematsu instantly said ‘It’s very good’ and ‘We can do it with this one,’” Suga recalled. “On my way back from the university, I was still wondering if this PET bottle was really suitable for draft sake. But no matter how many times I thought about it, the conclusion was the same: our bottle was absolutely perfect for this project.”
Complex bottles with frosted glass effect
Suga is a prudent person who is not readily convinced until he finds theoretical arguments that back up his conclusions. He found plenty of sound reasons in this case: The bottle - which is molded after a test tube-like PET preform covered with a colored functional film is inflated - is recyclable, light, easy to carry, stretchable, flexible and has excellent light-shielding and gas barrier capabilities. Immediately after his visit, the project picked up steam and the consortium adopted a classic design - black film with a traditional “kiriko” texture - for the draft sake called “Awanama.” The product became available in October 2018 and also has been exhibited at international trade fairs.
On a separate project, a bottle with a different design was selected for the Shirataki Shuzo brewery’s mainstay sake brand “Jozen Mizu no Gotoshi,” which also went on sale for the domestic market in October 2018. The bottle resembles the shape of its glass version but is embellished with a white film to enhance its light-shielding capability, and is intended for people wanting to drink sake during outdoor and leisure activities.
Pursuing novel PET bottles
Since joining DNP in 2008 after obtaining a master’s degree in organic chemistry from Chiba University, Suga has handled the development and later the sales of PET bottles with his boss and research partner, Takuma Miyawaki. When Suga joined DNP, the technology for making PET bottles had pretty much matured. In 1997, DNP was the first company in Japan to adopt for practical use the “In-line Molding Method,” in which the company ships bottle preforms to clients’ factories for inflating and molding before they are filled with a beverage. As of September 2018, DNP held the top share in the market for this kind of system: One-third of PET-bottle beverages sold in Japan were made with DNP’s aseptic filling system.
In 2013, 15 years after the system was established, Suga thought of developing a novel PET bottle by adding a film to cover the bottle preform. He began his research with Miyawaki, now manager of the new PET bottle project team, in which Suga is a member.
Initially, the research did not proceed smoothly and Suga experienced many failures in his search for suitable materials for an outer film and sure-fire ways to mold them. Suga believed that a container covered by a colored film would make it possible to hold contents that had not been adopted for ordinary PET bottles. It is, therefore, desirable to have light-shielding and gas barrier functions. “I experimented with everything I could find and even bought materials online,” he said.
Making bottles look sophisticated was not at the forefront of his mind, Suga says, but his luck changed months later when he accidentally found an experimental bottle had an imprint of a large fragment from a broken PET bottle that had been left inside the mold unnoticed. “I realized that the bottle can have a good external appearance if we make metal molds with patterns or some kind of design.”
But challenges remained. The most difficult task was bringing the bottle in line with strict guidelines set by the Council for PET Bottle Recycling. Under these guidelines, PET bottles must be transparent and their labels must be easily peeled off. Recycling is essential at a time when plastic garbage is posing a growing menace to the environment.
Teaming up with Miyawaki was crucial for solving such problems, Suga said. “I am very conservative and try to find reasons for any failure to fortify my theories for future use, while Mr. Miyawaki is a man of action and wants to try everything he can think of first,” Suga said. “We have very different personalities, but we are partners despite our 11-year age difference.”
In collaboration with another DNP development team, they succeeded in making the new PET bottle, whose surface is adorned with stylish holograms.
Responses in Paris and Hong Kong
At the 5th Salon du Sake European Fair for Sake and Japanese Beverages in Paris, France in 2018
Suga attended Salon du Saké, an international fair for Japanese sake in Paris, in early October, and the HKTDC Hong Kong International Wine & Spirits Fair as part of a delegation featuring consortium, public relations and other members to promote Awanama in the two cities. He received positive feedback from consumers and business operators.
“The greatest joy I felt since we developed the new PET bottle was when I directly received money from a Paris restaurant owner who bought five bottles of Awanama,” Suga said. “I always want to see results of my research efforts incorporated in products. The owner praised my bottle, too, after tasting the sake.”
“The new PET bottle is my biggest project at DNP,” Suga said. “The bottle has been adopted for two sake brands, but we must increase color variations of the outer film and take other steps to better cater to our clients’ needs. We want to use the bottle for beer, but doing so requires overcoming technological challenges such as enhancing the light-shielding and gas barrier functions. It can also be used for cosmetics and amenities, so its applications are limitless.”
DNP plans to strengthen development and sales of the new PET bottle, aiming to reach over ¥1 billion in sales in fiscal 2020.
- * Publication date : March 29, 2019
- * DNP department names, product specifications and other details are correct only at the time of writing. They are subject to change without prior notice.