Creating Products That Contribute to the Environment

The NGK Group considers contributing to society through business activities to be one of its most important missions. For nearly a century since its founding, NGK has made use of accumulated technologies to develop and provide products and technologies that reduce burdens on the global environment.

Development and Distribution of Products Contributing to Environmental Protection

Under our fourth Five-Year Environmental Action Plan initiated in fiscal 2016, NGK has set a goal of increasing sales of products that contribute to environmental protection by 60% compared with fiscal 2013 (and maintaining the sales percentage for products contributing to environmental protection at over 50% of all products).
In fiscal 2020, sales of products that contribute to environmental protection increased by 44% over fiscal 2013, which fell short of our fiscal year goal of 60%. Demand was down from forecasts due to factors such as a cooling down of the global economy from the effects of the COVID-19 pandemic.
We have a total of nine products that contribute to environmental protection, including two registered last fiscal year: gallium nitride (GaN) wafers and micro-lenses for ultraviolet LEDs. We are currently developing other products that contribute to environmental protection; for example, zinc rechargeable batteries, fuel cells, and subnano-ceramic membranes.

Definition of NGK Products That Contribute to Environmental Protection

  • Certified or awarded by third-party institutions
  • Control or reduce impact on the Earth’s environment
  • Reduce impact on the local environment

Sales Growth for Products Contributing to Environmental Protection (NGK Group)

Growth in sales of products contributing to environmental protection. Sales of products that contribute to environmental protection increased by 44% over fiscal 2013, which fell short of our fiscal year goal of 60%.

Figures are indexed with fiscal 2013 set at 100.

NGK Group Products Contributing to Environmental Protection


Picture of HONEYCERAM, ceramic substrate for catalytic converters. NGK’s HONEYCERAM eliminates a total of 4 million metric tons of NOx per annum.

HONEYCERAM is a ceramic substrate for catalytic converters to purify harmful contents in the exhaust of automobiles. It carries a catalyst that detoxifies harmful substances by chemical reaction, and its honeycomb structure provides a greater contact surface area for the exhaust and thus gives better purifying performance.
Since the launch of mass production in 1976, over 1.5 billion units have been shipped of this essential ceramic product for purifying exhaust. NGK’s HONEYCERAM eliminates a total of four million metric tons of NOx per annum*1, equivalent to double the annual NOx emissions in Japan*2.

  • Assumption based on installation of exhaust gas system in new cars that are not equipped with such systems
  • Source: OECD Environmental Statistics (2012)
NGK’s HONEYCERAM eliminates a total of 4 million metric tons of NOx per annum.

Diesel Particulate Filters (DPF)

Picture of diesel particulate filters. With a pore structure, they remove 99% of particulate matter from diesel exhaust gas.

The DPF is a porous ceramic filter used worldwide in the exhaust systems of diesel vehicles. With a pore structure, the filter ensures particulate matter (PM) is captured to purify the exhaust emitted from diesel vehicles. NGK is the only company to produce two types of DPFs based on both cordierite and silicon carbide. NGK’s ceramic technologies support further developments for diesel vehicles.
The honeycomb structure, where the inlet and outlet of the through-holes are alternately sealed, enables the thin ceramic walls to efficiently capture PM while exhaust passes through.

With a pore structure, they remove 99% of particulate matter from diesel exhaust gas.

Gasoline Particulate Filters (GPF)

Picture of gasoline particulate filters, which remove particulate matter emitted from gasoline engines.

GPFs are ceramic filters that remove particulate matter (PM) from the exhaust of gasoline-powered vehicles.
We developed this filter based on diesel particulate filter (DPF) technology, and succeeded in producing a GPF that can achieve high performance (captures more PM) and low pressure loss (lower fuel costs and higher output) at the same time through the use of our proprietary micropore creation and control technologies. We were the first to commercialize a GPF in 2012, and commenced mass production in January 2016 at one of our subsidiaries.
As automobile emission regulations throughout the world become stricter, we expect that demand for GPFs will increase. To respond to this demand increase, we are boosting production capacity.

In-Vehicle High-Precision NOx Sensors

Picture of in-vehicle high-precision NOx sensors. The nitrogen oxide concentration in the exhaust gas is measured with high precision in real time.

NGK developed the world’s first in-vehicle sensor to measure concentrations of nitrogen oxides (NOx) in exhaust in real time with high precision.
Specifically, the sensor is capable of measuring NOx concentration at the parts per million (ppm) level and can thus detect even very small amounts of the noxious substance. The sensor supports precise control of the exhaust purification device used in diesel vehicles, which leads to a reduction in NOx emissions and helps to promote the use of clean diesel vehicles.

NAS Batteries

Picture of NAS battery. Utilizing its large capacity to full advantage, it stabilizes fluctuations in the output of renewable energy such as wind and solar power by appropriately storing and discharging the electricity provided.

Providing clean energy that burns no fossil fuels and releases no CO2 emissions, renewable energy is on the rise worldwide. The NAS battery stabilizes fluctuations in the output of renewable energy such as wind and solar power—which are susceptible to weather conditions—by appropriately storing and discharging the electricity provided.
Increases in the amount of renewable energy depending on the season or time of day lead to electricity surpluses that make it difficult to constantly balance electricity supply and demand. NAS batteries use their high capacity to store excess electricity and enable supply–demand balance, thus making more widespread use of renewable energy practical.

Worldwide installations of NAS batteries, which have a total measured output of 580 MW and a discharge capacity of 4,000 MWh. Installed at over 200 facilities across the globe, they are the world’s most popular grid-scale battery storage.

Note: As of June 2021

Low-Level Radioactive Waste Treatment Systems

Picture of low-level radioactive waste treatment system to safely treat low-level radioactive waste generated at nuclear power stations.

NGK has developed a wide range of systems to safely treat low-level radioactive waste generated from nuclear facilities and has supplied these systems to nuclear power stations and related facilities across Japan. The systems are developed utilizing NGK’s proprietary treatment technology and high-performance filter-based dust collection technology.
We undertake a variety of engineering projects including design, manufacturing and site construction, and also provide a long-term maintenance service to deliver stable and high-level radioactive decontamination. NGK thereby provides essential support for the safe and stable operation of nuclear facilities.
In addition, we focus on the development of new systems for treating various types of radwaste expected to be generated from the decommissioning and dismantling of aging nuclear reactors.

Importance of Treating Radioactive Waste

When treating and disposing of waste generated in radiation-controlled areas, including nuclear power stations, it is critically important to prevent the spread of radioactivity via the release of radioactive matter. This requires special treatment and disposal methods that differ from those for general waste.

Wavelength Control Drying Systems

Picture of wavelength control drying system, which reduces drying time to less than half that of conventional methods.

Our wavelength control drying system uses a proprietary heater unit developed in-house to promote the evaporation of solvents.
This system uses specific infrared frequencies to effectively facilitate evaporation, shortening drying time to approximately ½ to ⅓ of that required for conventional drying methods using heat, and reducing power consumption by 30 to 50%. It is also possible to suppress binder segregation, which is an expression of variations in concentration that occur due to drying of the soluble component in films during drying, by 30 to 40% (in-house binder segregation study).

Gallium Nitride (GaN) Wafers

Picture of FGAN gallium nitride wafers, which make possible high-output and high-efficiency semiconductor lasers.

This low-defect density gallium nitride (GaN) wafer uses NGK’s original crystal growth method covering the entire wafer. With the Minamata Convention on Mercury going into effect in August 2017, there is expected to be high demand for high-output, high-efficiency semiconductor lasers using GaN wafers as a substitute for ultra-high-pressure mercury lamps. They are expected to see use in light sources for projectors, stadium lighting, car headlamps, and other products.
We see applications for the gallium nitride (GaN) wafer in high-frequency devices for next-generation 5G wireless base stations, and power devices key to realizing a low-carbon society such as inverters for electric vehicles and power conversion equipment for photovoltaic power.

Micro-Lenses for Ultraviolet LEDs

Picture of micro-lenses for ultraviolet LEDs. Quartz glass lenses are used for ultraviolet LEDs, which replace mercury lamps.

Micro-lenses for UV LEDs are transparent quartz glass lenses developed by NGK that are used in UV LEDs in place of mercury lamps. Mercury lamps are currently used in light sources used in applications such as the sterilization of water and air. However, factors such as the Minamata Convention going into effect are increasing the likelihood that mercury lamps will be banned and sparking interest in UV LEDs that do not use mercury. NGKs micro-lenses for UV LEDs are characterized by a cavity that holds a UV LED chip, a feature that improves UV LED efficiency and lowers costs.

Environmental Labeling and Declarations

Because the majority of products handled by the NGK Group are B2B products, environmental labeling is not applicable; however, we work to accommodate customer preferences with regard to this on a product-by-product basis.