Non-edible plant based bioplastic featuring Japanese lacquerware

In order to create the new cellulose-based bioplastic, NEC developed a unique technology for mixing additives to adjust coloration and light reflectance of the material, enabling, for the first time, the realisation of optical properties, similar to the deep and shiny "Urushi black" colour of high-grade Japanese lacquerware.

The new plastic balances a high level of environmental friendliness and decorativeness and makes it possible to mass produce products of various shapes and patterns using the usual moulding process for ordinary plastics.

Masatoshi Iji, Research Fellow, IoT Devices Research Laboratories NEC Corporation commented: "In response to the depletion of resources and food shortage problems, the need for non-edible-plant-based plastics is increasing. In addition to NEC's history in the development of a unique cellulose-based plastic using non-edible plant materials for use in durable electronic products, we have now developed a new bioplastic that, in addition to high functionality, realises the decorativeness of Japanese lacquerware, which is highly evaluated throughout the world, and illustrates a beauty well beyond what petroleum-based plastics can provide."

This development was carried out in collaboration with the Kyoto Institute of Technology's Future-Applied Conventional Technology Centre, which is known for its outstanding achievements in future-applied conventional technology research and Dr. Yutaro Shimode, a prominent Japanese lacquerware artist.

The development process involved, first, the fabrication by Dr. Shimode of a Japanese lacquerware ‘Urushi craft’ model (transparent resin plate repeatedly coated with Japanese lacquer and polished by hand) that served as the standard for the advanced optical properties exhibited by high-quality Japanese lacquerware. Scientific analysis was performed on Japanese lacquerware at the Kyoto Institute of Technology.

Based on the results, NEC then developed an optimised technology for modifying and mixing of the additives.

Going forward, NEC will pursue business partnerships aimed at commercialising the new bioplastic in durable products and high-grade materials that require a high level of decorativeness, such as the interior components of luxury cars.

Key features of the ‘Urushi black’ bioplastic:

1. Use of non-edible plant materials that are readily available as the main ingredient.

The new bioplastic uses cellulose resin produced from cellulose that is widely available from non-edible plant resources, such as grasses, the stalks of cereal crops and wood, and has the potential to be used as a substitute for petroleum.

2. Realises the advanced optical properties (Urushi black) of high-grade Japanese lacquerware.

Black colouring agents and highly refractive organic ingredients were mixed with the above cellulose resin as special additives to adjust the resin's coloration and light reflectance properties.

By dispersing the additives into fine particles, NEC became the first to achieve the advanced optical properties exhibited by high-grade Japanese lacquerware. The new bioplastic was able to exhibit the deep and shiny ‘Urushi black’ colour characteristic of Japanese lacquerware, at a quality similar to the high-grade ‘Urushi craft’ model fabricated by Dr. Yutaro Shimode.

3. The new bioplastic can be mass-produced into products of various shapes using the moulding process for ordinary plastics.

Conventionally; lacquerware is produced by coating the surface of substrates with lacquer and polishing them. For this newly developed bioplastic, the materials can be heated, melted, and injected into moulds (mirror-finishing) to form shapes (injection moulding), as with ordinary plastics. This makes it possible to mass-produce the bioplastic into products of various shapes and patterns.

NEC is scheduled to present this technology at the 24^th Material Processing Technical Conference, to be held at Waseda University in Tokyo from 25^th to 26^th November 2016.