From the Land of Innovation: A T-shirt that Decomposes in Six Days Flat

Away from petroleum-based fabrics, comes an innovation — a fibre made from polylactic acid (PLA), a biodegradable plastic made from corn, under the brand name Highlact. Could it be the best material to replace polyester in terms of quality, cost and supply? texfash.com explores.

Long Story, Cut Short
  • There's an opportunity to replace petroleum-based fabrics with PLA using traditional Japanese skillsets.
  • PLA has been used in nonwoven fabrics, but couldn't stand a chance for apparel as it cannot stand heat beyond a point.
  • PLA has second highest consumption volume of any bioplastic of the world, and is used in a large variety of consumer products.
Highlact products will biodegrade under certain compost conditions. At a compost temperature of 68°C and a moisture content of around 50%, the compost decomposes in six days flat!
And, it withers away Highlact products will biodegrade under certain compost conditions. At a compost temperature of 68°C and a moisture content of around 50%, the compost decomposes in six days flat! HighChem Company Limited

Almost 2,400 years ago, Plato wrote in Republic: "Our need will be the real creator." Over time, the idea transmutated into the widely known English proverb: Necessity is the mother of invention. These need and invention bits rung true for Yuichi Taka.

The need was to move away from petroleum-based fabrics, and the invention (actually, innovation) has been a fibre made from polylactic acid (PLA), a biodegradable plastic made from corn, under the brand name Highlact.

But then, PLA itself was nothing new—it has second highest consumption volume of any bioplastic of the world, and is used in a large variety of consumer products such as disposable tableware, cutlery, housings for kitchen appliances. It can degrade into lactic acid, making it suitable for use as medical implants in the form of anchors, screws, plates, pins, rods, and mesh. It breaks down inside the body between six months and two years.

There was just one problem: PLA couldn't stand heat beyond a point. It has been used in nonwoven fabrics, but wouldn't stand a chance for apparel.

Taka, Director at Tokyo-headquartered HighChem, however, had ideas. "When we were being forced to change materials due to sustainability issues in the fashion industry, we thought that PLA was the best material that could replace polyester in terms of quality, cost and supply.

"PLA is a synthetic fibre derived from biomass such as corn, and we hope that we will be able to supply textured fabrics like polyester in the near future. Of course, there are some problems such as heat resistance, but research and development are ongoing by the day. As for the price issue, we are confident that the production cost will eventually decrease because our partner mill in China is expanding their production capacity by more than five times and would be supported by the Chinese government."

There's a technicality here, because technically PLA is still a polyester, a thermoplastic polyester to be precise. The Wikipedia entry on the subject points out: "Although the name 'polylactic acid' is widely used, it does not comply with IUPAC standard nomenclature, which is 'poly(lactic acid)'. The name 'polylactic acid' is potentially ambiguous or confusing, because PLA is not a polyacid (polyelectrolyte), but rather a polyester."

PLA is a synthetic fibre derived from biomass such as corn, and we hope that we will be able to supply textured fabrics like polyester in the near future. Of course, there are some problems such as heat resistance, but research and development are ongoing by the day. As for the price issue, we are confident that the production cost will eventually decrease because our partner mill in China is expanding their production capacity by more than five times and would be supported by the Chinese government.

PLA should be blended with other biodegradable materials like cotton and Tencel. After many trials and faults, HighChem reached the best mixed for blending with cotton and Tencel: cotton/PLA 70%/30% and PLA/Tencel 55%/45%.
The right blend PLA should be blended with other biodegradable materials like cotton and Tencel. After many trials and faults, HighChem reached the best mixed for blending with cotton and Tencel: cotton/PLA 70%/30% and PLA/Tencel 55%/45%. HighChem Company Limited

Beyond a name, and beyond polyester

Taka saw a chance to work on PLA, particularly the heat aspect. "We in Japan have a long history of research and development of PLA fibres (for over 40 years). And there are excellent companies with traditional technologies, such as spinning, knitting, weaving and dyeing.

"We understood that it was time to grab that big chance by promoting PLA fibres again because we face a critical situation today from greenhouse gases globally, and it would be a paradigm shift. Durable materials are good for the environment. We believe there's an opportunity to replace petroleum-based fabrics with PLA using traditional Japanese skillsets."

Taka saw two merits in PLA. First, it was a biomass-derived synthetic fibre. And second, it was biodegradable. These two factors scored over the petroleum-based fibres polyester and polyurethane. Neither can decompose for hundreds of years.

"Then, we decided that PLA should be blended with other biodegradable materials like cotton and Tencel. After many trials and faults, we reached the best mixed for blending with cotton and Tencel: cotton/PLA 70%/30% and PLA/Tencel 55%/45%," says Taka.

The inherent problems with PLA had to be surmounted.  Explains Taka: "We understand there are two problems with the heat resistance of PLA. The first is that the melting point of PLA fibre is around 170°C; so, it cannot be ironed at medium or higher temperatures. The other is that normal PLA fibres are limited to 100-110°C in the piece-dyed process. If the temperature is higher than 110°C, the fabric will become harder, and it would be impossible to be dyed in dark colours like black or navy blue."

And then, the HighChem team worked harder. "We improved Highlact's heat resistance by mixing plant-derived modifiers with the raw materials. As a result, it could be dyed under the same conditions (high temperature and high-pressure) as polyester. In addition, we found that the dyeing curves of polyester and PLA were different—it was difficult to achieve the target colours with the same dyes as polyester. Therefore, we developed new, exclusive disperse dyes for Highlact with a global dyes manufacturer. We will support dyeing problems by supplying these dyes together with the Highlact fibres to customers. We believe it is a good solution for both."

And, it withers away. Highlact biodegrades under certain compost conditions. At a compost temperature of 68°C and a moisture content of around 50%, the compost decomposes in six days flat (see pic below).

Japan has a long history of research and development of PLA fibres (for over 40 years). And there are excellent companies with traditional technologies, such as spinning, knitting, weaving and dyeing. And it was just this opportunity seized to work towards a paradigm shift, especially at a time when the earth faces a critical situation from greenhouse gases globally. And, HighChem believes there's an opportunity to replace petroleum-based fabrics with PLA using traditional Japanese skillsets.
Looking back to look ahead Japan has a long history of research and development of PLA fibres (for over 40 years). And there are excellent companies with traditional technologies, such as spinning, knitting, weaving and dyeing. And it was just this opportunity seized to work towards a paradigm shift, especially at a time when the earth faces a critical situation from greenhouse gases globally. And, HighChem believes there's an opportunity to replace petroleum-based fabrics with PLA using traditional Japanese skillsets. HighChem Company Limited
 
 
  • Dated posted: September 26, 2022
  • Last modified: September 26, 2022