Introducing Panasonic’s Sustainable Plastic Alternative

The use of petroleum-derived plastic has increased exponentially over recent decades, reaching some 300 million tons per year and making it one of the most pressing environmental issues. Despite growing awareness of the dangers posed by plastic, including ecological pollution and carbon emissions, the global recycling rate of this material is a mere 9%.

Panasonic is committed to helping mitigate these issues. In 2015, the company began exploring ways of reducing usage of petroleum-derived plastics, and central to this is its development of sustainable alternatives to plastic, created with cellulose fiber sourced from plants.

A frontrunner among these is “kinari,” a versatile material with the potential to revolutionize manufacturing while helping to realize a sustainable, “circular society.” Born after a team of environmentally conscious engineers hit upon the idea of amalgamating biomass, kinari is an all-new, high-density material composed of cellulose fiber taken from a variety of “waste” plant materials and bonded together by a minimal amount of oil-based resin.

“Extensive testing shows that
kinari has no downsides when compared to plastics”

Extensive testing shows that kinari has no downsides when compared to plastics. Moreover, it possesses remarkable versatility in terms of the forms it can take—it may be formulated to be simultaneously lighter and stronger than plastic, or alternatively given a pliable quality. An incredibly wide potential for finishing and coloring, meanwhile, may challenge consumers’ ideas of how sustainable materials can look and feel. The material has already been used to create products ranging from sleek and modern, to ones inspired by nature.

It is kinari’s unique production process that gives it such flexibility. “In other cellulose-derived materials, white elements of the fiber will be given a brown-ish tinge by the high temperature heating which is part of the formulation process, and this limits scope for coloring,” says Masashi Hamabe of Panasonic Holdings Corporation Dept., Manufacturing Innovation Division.

“For kinari, however, we use lower temperatures that preserve this whiteness, and thus allow the material to be given light and delicate hues. Further, by carefully controlling temperature during the molding process, it is possible for kinari to manifest the color, texture and smell of the waste material used for that batch.”

This quality has resulted in some users mistaking an item made with kinari for real wood, while others have held products made with kinari up to their noses in order to breathe in the heady aroma—according to Hamabe’s colleague Satoshi Wada of Panasonic Production Engineering Co., Ltd., Mold & Die Business Center/Technology Department.

“Some users mistake
an item made with kinari for real wood”

The word “kinari” is a Japanese term meaning “unbleached cloth,” and as a brand name it reflects the material’s blank canvas-style potential to take on a myriad of appearances, textures, and colors. “It also evokes the abundant forestry that is characteristic of Japan,” says Hamabe.

The kinari production process is an appropriately eco-friendly one. Previously, making material from cellulose fiber has required soaking source “ingredients” in water, to create fibers. This technique emits enormous amounts of CO₂, and uses considerable energy, when fibers are dried and combined with resin to hold them together. The kinari team, however, has developed a method in which source materials are broken into fibers in melted resin, without the need for water. This innovative process reduces CO₂ emissions by 1.8 kg per kilogram, compared to cellulose fiber materials produced using water.

Another key advantage kinari offers over other plant-based plastic substitutes is that such materials are typically made with the same crops used for foodstuffs. This has been a factor in the global rise in food prices over recent years, something now a major concern even in wealthier nations. Instead of contributing to pressure on the food supply chain, kinari’s core element of cellulose fiber is derived from a diverse range of waste substances, including used coffee grounds, excess trees cleared from woodland and residues from sake brewing.

This cellulose fiber comprises the bulk of kinari’s formulations, with the project’s engineers making steady progress on the material’s ratio of biomass versus oil-derived resin. Back in 2019, kinari comprised 55% cellulose fiber. In 2021, 70% biomass content was achieved, with that figure reaching 90% the following year.

Ultimately, the kinari team is striving towards a 100% biomass formulation that will eliminate the need for petroleum-based resin entirely—the cellulose-fiber biomass instead binding itself together. This is proving to be perhaps the greatest challenge in kinari’s development.

The kinari team is taking a two-pronged approach to achieving circularity in production, use and recycling. When a product made from kinari reaches the end of its lifespan, the intention is for it to be recyclable via a choice of either natural biodegradation, or alternatively recycled via a proprietary, hi-tech process to form further supplies of kinari.

The first method, biological recycling, is already possible—as verified by a third-party organization, when mixed with industrial compost kinari is reincorporated into the earth in a period of nine months. From there it may be reused as a plant resource.

The second technique, material recycling, is something the kinari team is presently working hard to develop. “A fully closed-loop society is something we are aiming to achieve with kinari,” says Hamabe. Material recycling, together with the complete elimination of oil-based resin from kinari’s composition, should bring the team closer to that goal.

For businesses, kinari offers a plug-and-play alternative to plastic that may be easily adopted. “Manufacturers can switch to kinari without having to invest in new equipment,” says Wada. “With extensive experimentation, we have developed a material that allows items to be manufactured in the same manner as plastic.”

Only a few short years into its development, kinari is already capturing the imaginations of both Japanese domestic and international brands across a broad spectrum of industries. Some have already collaborated with Panasonic to develop products made using kinari, and report that their customers have praised the nature-like qualities of these items.

Japanese beverage giant Asahi, for example, worked with the kinari team to create a distinctive “Forest Tumbler” whose “woody” character complements the foaminess of the firm’s best-selling beer. The tumbler was designed to replace single-use plastic cups at Asahi-sponsored events, and has also been released to the domestic consumer market. A soap dispenser and soap dish, created with Osaka-based K-WORLD ism, offer similarly wood-like textures.

“kinari is capturing the imaginations of
both Japanese domestic and international brands”

The plant-based kinari takes on a sleek, contemporary form in products created by Madrid-born, eco-conscious fashion brand ECOALF, whose slogan “Because There Is No Planet B” resonates with the kinari team’s own commitment to sustainability. ECOALF has used kinari for fasteners, buttons and other parts in the label’s Act collection, exclusive to Japan and released in 2022. ECOALF’s Japanese stores have been using hangers made from kinari.

“Interest in kinari from overseas companies is coming mainly from advanced economies in Europe and Asia, where previously widespread use of plastic is being reined in by new laws and regulations,” says Wada.

A tie-up with Fukuchiyama City in Kyoto Prefecture, meanwhile, underlines the importance of educating the next generations on sustainability and the SDGs. At Fukuchiyama City Elementary and Junior High School, kinari will be utilized both for students’ bento boxes and other lunchtime tableware and as a teaching material for learning about the environment, from fall 2023.

The cellulose fiber content of the kinari to be adopted by the school is taken from trees felled from local woodland. This illustrates the potential of kinari as a sustainable material whose flexible range of “ingredients” can be sourced from a given region, and the resulting kinari then used to manufacture products in the same locality.

Beyond these incipient but already well-received consumer goods, kinari also has potential for industrial and architectural usage. Ami Okabe of Panasonic Holdings Corporation, Manufacturing Innovation Division, is enthusiastic about the material’s scope for outdoor applications. “In agricultural or fishery usage, plastic carries the risk of microplastics being released into the environment,” she explains. “A biodegradable material, however, can avoid the accumulation of plastic in the natural world.”

“A biodegradable material can
avoid the accumulation of plastic in the natural world”

Under its new environmental policy, named Panasonic GREEN IMPACT (PGI), the company is seeking to increase the number of its businesses related to the circular economy. In 2021, Panasonic initially had six businesses related to the circular economy; however, the number has been steadily increasing over the years towards the final target of 13 businesses by 2024. Ryuji Shimono, General Manager, Quality & Environment Division, Panasonic Operational Excellence Co., Ltd., sums up the significance of the company’s efforts to develop cellulose-based alternatives to plastic. “Our cellulose fiber-based materials, we believe, are a realization of the integrated approach of decarbonization, the circular economy and nature-positive worldview that is needed to attain a sustainable, carbon-neutral society,” he says.

“Through our development of fully biodegradable materials that utilize plant fibers to help advance the move away from plastics and fossil extracts,” adds Shimono, “we are contributing to Panasonic GREEN IMPACT’s mission of realizing both a sustainable global environment, and a better life for all.”