In recent years, awareness of the global conservation movement has been spreading rapidly. In the wake of the Kyoto Protocol, consumers have become increasingly conscious of the need to reduce their carbon footprint and are demanding more environmentally friendly products. In line with this trend, Fuji Xerox has been actively promoting research and development on how to replace the plastic parts in copy machines and printers with more environmentally friendly materials.

Existing oil-based plastics emit large amounts of carbon dioxide when discarded. On the other hand, biomass plastics produced from raw organic materials such as corn emit significantly less carbon dioxide. This is because the plants absorb carbon gases in the atmosphere through photosynthesis and the absorbed carbon gases are then used to produce plastic materials. As a whole, the amount of carbon gases emitted during disposal can be offset by the amount of carbons absorbed. This is known as “carbon neutral” (see Figure 1).

Figure 1: The “Carbon Neutral” Concept

Nonetheless, biomass plastics face many challenges with respect to durability and safety. For example, some exhibit brittleness against external shock and poor flame resistance. As a result, biomass plastics have not been adopted in high-durability electrical products, including copy machines.

To overcome these challenges, Fuji Xerox has succeeded in developing a new biomass plastic. This new plastic contains upwards of 30 percent by weight of a resin material, polylactic acid (PLA), that is derived from corn. Despite this relatively high inclusion level compared to other plastics, we have achieved the same strength and flame resistance found in conventional plastics. This new plastic has obtained the “Biomass Plastics Mark” of the Japan BioPlastics Association (JBPA) and is already being used in Fuji Xerox products.

One of the greatest challenges we faced in developing a new biomass plastic revolved around the hard and brittle nature of polylactic acid (PLA). Fuji Xerox thus used a polymer alloy technology that mixes PLA with oil-based plastics. Initially, PLA was difficult to blend with oil-based plastics. For example, using simple blending, the oil-based plastic was granulated and dispersed in PLA (see Photo 1), resulting in insufficient strength. To overcome this problem, we developed new additives and new kneading and molding technologies to blend both materials homogenously. This was our greatest breakthrough in new technology development. Looking at this new biomass plastic under a microscope, you can see that PLA and the oil-based plastic are homogenously blended (see Photo 2). In this way, it has become possible to produce a high-strength plastic that contains large amounts of plant-based PLA.

Biomass plastics still have more challenges to overcome. Although their environmental features are highly regarded, they still cost more to produce than oil-based plastics, and this has been a stumbling block in promoting the further expansion of biomass plastics. Accordingly, Fuji Xerox will continue to pursue cost-reduction activities, thus clearing the way to the widespread adoption of biomass plastics.

Photo 1		Photo 2
This shows the internal structure of a polymer alloy when PLA (black area) and an oil-based plastic (white area) are simply blended. Since the brittle PLA disperses around the oil-based plastic, sufficient strength cannot be obtained.		This shows the internal structure of a polymer alloy when PLA and an oil-based plastic are blended under the new conditions. The PLA (tiny white particles) is encapsulated by the oil-based plastic (black area).