In consideration of the environment, Canon promotes activities to reduce environmental impact in all three stages of the product lifecycle: Produce, Use, and Recycle. As the basis of its efforts, Canon also focuses on the development of unique environmental technologies.
High-Performance Bio-Based Plastics [Produce]
Development of Industry's Largest MFD External Parts Using Bio-Based Plastics
More and more attention is being paid to bio-based plastics, made from raw materials extracted from plants, for its benefits in terms of reducing environmental impact. However, their applications have been limited due to the fact that they offer less flame retardancy, shock resistance, heat resistance and moldability than conventional petroleum based plastics. It has only been possible to use bio-based plastics in small internal components of office MFDs.
In 2008, Canon, in collaboration with Toray Industries, Inc. established new material design and molding technologies, and succeeded at developing high-performance bio-based plastic with significantly improved material properties. The flame retardancy of this new plastic is the world's first bio-based plastic applicable for use in multifunction office systems to achieve 5V classification under the UL 94 flammability testing program.*1 With this new material now capable of being used on exterior product components, Canon has employed it in its imageRUNNER ADVANCE series of MFDs.
In 2010, Canon and Toray developed the largest*2 external components made from bio-based plastic to be used in the copier and MFD industry. These components, manufactured with Canon's advanced plastic injection metal mold technology, used in the manufacturing of large components, and Toray's material design technologies, are used in Canon digital production printers.
These parts are approximately 11 times as large as the parts used in the imageRUNNER ADVANCE series, and 6.5 times heavier.
Bio-based plastics are environmentally friendly, producing approximately 20% less CO2 during its production when compared with petroleum-based plastics. Canon is continuing with further technological development, making improvements to bio-based plastics in order to expand their range of applications and usage.
- *1 UL 94 standard
A safety standard set forth by Underwriters Laboratories of the United States and widely used in the grading of the flammability of materials. In accordance with this standard, plastics may be graded, in order of flammability, as 5V, V-0, V-1, V-2, or HB. Of these, 5V represents the most stringent set of conditions, and plastic having achieved the corresponding level of performance can be used as casing materials for large items of office equipment and home appliances.
- *2 As of August 10, 2011. According to research by Canon and Toray.
Technologies for Replacing Volatile Organic Compounds [Produce]
Reducing VOCs in the Manufacturing Process
Organic solvent-based paint and cleaning agents are commonly used in a variety of parts processing. Canon is no exception, using organic solvents in the painting and cleaning processes for external components used in printers, cameras, and other products. These solvents produce VOC (Volatile Organic Compound) gases when used, creating a need to reduce emission levels.
Canon has been working on significantly reducing VOCs emissions by switching to low-VOC cleaners and paints, and introducing solvent recovery equipment.*3 The company has developed VOCs-free water-soluble paint, and is already moving away from traditional VOC solvents in its painting process, using water-based paint with water as the main solvent for certain parts found in Canon compact digital cameras.
Canon has also significantly limited emissions in the cleaning process by switching to cleaners using low-diffusion VOCs that enable easy gas recovery and by introducing production equipment with recovery and recycling functions. Furthermore, the company is switching to low-VOC cleaning agents.
- *3 Solvent recovery equipment
Used for recovering and concentrating low-density VOC emissions, the technology enables the recovery of 90% or more of VOC emissions. High-density VOC emissions are liquefied and recycled during the cleaning process.
Cleaner-Free Developing Technology [Produce]
Creating Smaller, More Energy Efficient MFDs
In MFDs, after toner is transferred from the photosensitive drum to the intermediate transfer belt, some toner still remains on the photosensitive drum. Although this residual toner carries an uneven electric charge, Canon employed a supplementary charged brush to reapply a charge, reducing unevenness and stabilizing the amount of residual toner that is reclaimed by the developing roller.
Doing away with the need for the residual toner cleaning mechanisms required in previous devices, this cleaner-free system makes possible more compact MFDs. The reclaimed toner, which had been disposed of in the past, is reused for increased efficiency.
Furthermore, the imageRUNNER ADVANCE series of office MFDs uses low-melt-point toner, which enables fixing at a lower temperature than in the past for improved energy efficiency. With conventional supplementary charged brushes, however, the brush can become dirty, which could lead to poor imaging performance. Canon resolved this problem with an additional supplementary rotating fur brush that further enhances the performance of the cleaner-free system.
This cleaner-free system has contributed to the realization of more compact and more energy efficient imageRUNNER ADVANCE series MFDs.
Ozone-Free Electrical Charging Technology [Use]
Reducing Ozone Emissions to Approximately 1/1000 or Less
Electrophotographic products such as laser printers and MFDs make use of an electrically charged photosensitive drum to generate images. The conventional corona charging method involves the application of voltages ranging from about 5 to 10 kV, which results in corona discharge*4 and generates ozone (O3).
Eliminating the generated ozone required the introduction of an ozone filter, coupled with an airflow structure that reliably directs ozone to the filter.
To address this problem, Canon developed a roller charging method that charges the photosensitive drum by applying a voltage generated through the superposing of an AC voltage over a DC voltage to a conductive roller. Compared to the corona discharge method, which discharges into the air, this new method reduces ozone generation to levels no higher than about 1/1000, and voltage to about one-fifth of previous levels. The adoption of this technology eliminates the need for special systems to deal with ozone, enabling the realization of smaller laser printers and MFDs.
- *4 Corona discharge
A discharge phenomenon that occurs when voltage is applied to a pointed (needle) electrode and produces a light (corona) that can be seen in darkness.
Toner Fixing Technology [Use]
Dramatically Reduced Power Consumption in Standby Mode
In laser printers and MFDs, toner is fixed to the paper by heat and pressure via the fixing roller. With conventional fixing roller systems, the roller must be kept hot at all times by a heater located inside the roller, even when in standby mode.
On-Demand Toner-Fixing Technology (SURF)
Canon's on-demand toner-fixing technology employs a linear ceramic heater and a fixing film sleeve with high thermal conductivity and low thermal capacity. The thin fixing film is brought into contact with a ceramic heater, which operates only when the fixing film rotates, fixing the image by applying heat to the toner through the film. This mechanism eliminates the need for power while in standby and, in some products, realizes zero power consumption by the fixing unit when in standby.
For color office machines, Canon developed color on-demand toner-fixing technology. The fixing belt uses a 3-layer structure in which a rubber layer, which improves the fixing of toner, is sandwiched between a base layer of monochrome fixing film and a surface layer. The base layer is made of either resin or metal, with the appropriate material chosen for each product in accordance with different product needs.
Induction Heating Fixing Technology
"Induction Heating (IH)*5 toner fixing" uses a fixing roller consisting of a thin-walled metal pipe with a thin coating. The roller is heated using induction heating by applying a high-frequency electrical current through a coil built into the roller. Because the self heating roller is subject to thermal change, ensuring durability had posed a challenge. Following an examination of the thermal properties of materials and the mechanical characteristics of the technology, Canon achieved an improved roller-holding method and fixing unit structure, and completed a highly durable fixing roller. To ensure stable temperature control, the company also developed a low-loss, high-frequency inverter power supply. This technology reduces standby times to one-tenth of previous wait times while cutting energy consumption by about 55% compared with previous systems (based on an in-house comparison).
- *5 Induction Heating (IH)
A heating method found in electric rice cookers and other cooking appliances that makes use of magnetic induction.
Toner Cartridge Recycling Technology [Reusage]
Achievement of Recovery with No Landfill Use
Canon led the way for the toner cartridge industry all over the world in the realization in 2002 of a material recycling plant wherein various stages from toner-cartridge crushing to material separation and conversion into plastic pellets*6 are carried out automatically. Plastic is the most commonly used material in the outer casing of toner cartridges, and after this has been separated with very high accuracy based on aspects such as color and weight, it is converted into pellets, enabling its reuse in new toner cartridges.
This closed-loop recycling that Canon has achieved provides for the semi-permanent usage of plastic materials. Meanwhile, metals separated from the crushed material can also be put to use in other applications, making recovery possible without the need for landfill disposal.
- *6 Pellet: small homogenous particles or nurdles.