Makanai Makanai

Innovative Resin Glass
Boasting Exceptional
Beauty and Strength

Ishikawa Jyushi Kogyo

Business operator: Ishikawa Jyushi Kogyo K.K.
Project manager: Robert Amakasu

These drinking vessels have the look and feel of glass, yet are actually resin-based products made from a new material called tritan. Plakira, the original brand by Ishikawa Jyushi Kogyo K.K., is more than 250 times stronger than glass, making it very difficult to break no matter how hard it’s dropped. It’s also heat resistant up to over 100 degrees Celsius and cold resistant as low as –30 degrees Celsius. The shape and color of the material remains unchanged even when put in the dishwasher or used with alcohol or bleach. Its lightness and durability make it perfect for the outdoors, barbeques and home parties.

But it’s not just the functionality of the material that has it in the spotlight. The company has succeeded in developing proprietary technology to make the material transparent and realize a variation in thickness, which were considered difficult with resin. The simple design featuring gentle curvature gives it a high-quality feel. Skilled artisans provide the final touches manually to ensure even higher quality, including a last polish to give it that extra luster and a burner finish for the rim. This enables the company to allay the concerns that come with plastic tableware — that is, being thought of as cheap-looking and fake — for an article of rare beauty that people will want to use for many years. The product adds new value to the world of tableware.

Plakira Manufacturing Highlights

  • No Other Notebook Like It on Earth

    Polishing the mold

    The mold that the resin is poured into is designed and manufactured in-house. With the assistance of a business partner, skilled artisans have to meticulously polish the mold over the course of an entire day to remove any unevenness. The mold is given a mirror finish to make sure that the vessels are extremely transparent. This is one of the most important processes behind the Plakira brand.

  • Original Ink - The More You Use It, the More It Becomes a Part of You

    Finishing the rim using a burner

    The melted plastic, which has been heated for three hours at 80 degrees Celsius, is poured into the mold all at once and then solidified via a process known as injection molding. The part where the resin flows into (“gate”) is removed after the molding and then the vessel is polished until the joints become invisible. In particular, the rim, which comes into contact with the mouth, is heated with a burner to make it smooth. The time and effort given to the vessels by the skilled artisans are directly connected to their high quality.

  • Konnyaku Gains Global Attention

    The vessel won’t break, no matter how hard it’s bent

    Tritan is a state-of-the-art co-polyester resin developed by U.S.-based Eastman Chemical Company. It boasts exceptional impact resistance and won’t break or crack even when run over by a car. Since it doesn’t contain any environmental hormones, it can safely be used by children. This safety has been highly acclaimed and tritan-made tableware has been introduced to a number of places such as leading restaurants and hotels.

  • All Eyes on Japan's Unique Washi

    A large variety of sizes

    The broad lineup of products includes wine and beer glasses and mugs. The popular “Yuragi Tumbler” is perfect as a gift that comes with a lifetime non-breakable guarantee and is available in many color variations. Having a thick base and very thin rim gives rise to an exquisite gradation that provides a beautiful finish.


Takuma Hirose

Tsutomu Ishikawa

Tsutomu Ishikawa is executive director of Ishikawa Jyushi Kogyo K.K. After graduating from the Department of Systems Innovation, Graduate School of Engineering, The University of Tokyo in 2007, he entered P&G Japan, where he was in charge of business planning and sales and distribution strategy for Japan and abroad. He has been in his current job since August 2016 and is tasked with the branding of Plakira.

Aiming to Have Plastic Tableware Seen in a More Positive Light

For half a century, Ishikawa Jyushi Kogyo has been engaged in the production of plastic products such as tableware, industrial components and Buddhist altar fittings. The company harbored a strong desire to change the deeply rooted perception of plastic tableware as a throwaway item. An encounter with the new material tritan has opened up a whole new world of possibilities.

With the aim of creating an unprecedented product durable enough to be used for many years and an aesthetically pleasing design that people won’t tire of after 10 years of use, Ishikawa Jyushi Kogyo teamed up with the Kanazawa-based venture firm secca inc. to develop the product over a five-year period. Molding technology and know-how built up in the plastics industry were leveraged to overcome the issue of air bubbles and impurities getting mixed up in the material.

A clever mold design and production method served to enhance transparency while success was also achieved in making the rim a mere 1.5 mm thick. With Plakira, aesthetic beauty, right down to the minute details, has caused a big stir. The product is now used in a number of different places that include restaurants and luxury hotels in Japan and beach resorts overseas. Going forward, the company is looking to expand its sales channel into North America to take advantage of the thriving outdoor culture as well as to further advance the product. In addition to expanding the product offerings, Ishikawa Jyushi Kogyo is passionate about pursuing development that challenges subtleties that provide a little more sparkle.

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The company secca inc. supervised the design of Plakira. Attention has been drawn to its unique manufacturing method that combines cutting-edge digital technology and traditional craftsmanship. There is a commitment to functional beauty even to the handle of a cup. With the “Yuragi Tumbler,” the rim was given an undulating wave shape and the bottom inside was designed in a triangular shape to allow air to pass through for easy drying even when stacked one on top of the other or turned upside down. The company utilized 3D computer aided design (CAD) and 3D printing for repeated trials and verifications to ensure a well-thought-out and exceptionally minimalist design.



Kaga-shi, Ishikawa

Ishikawa Prefecture boasts a rich food culture typified in Kaga cuisine as well as tea ceremony culture. A manufacturing culture has taken hold here, with blossoming traditional crafts such as Kutani ware and Wajima lacquerware. One doesn’t have to go far to get a feel for the history of the area’s craftsmanship with the beautiful Tsuzumi Gate of Kanazawa Station. Since its earliest days, Ishikawa Jyushi Kogyo has been involved in the production of tableware that is closely entwined with food culture.



Ishikawa Jyushi Kogyo K.K.

Established in 1947, Ishikawa Jyushi Kogyo started with the sale of base wood for Yamanaka lacquerware before shifting to the production of plastic lacquerware for mass-produced items such as chopsticks and plates. Since then, the company has handled a wide range of plastic products that include industrial components and Buddhist altar fittings in addition to tableware goods, taking charge of the entire production process from design through mold production, molding and processing. In 2011, the company launched its own brand, Plakira.