Japan Company Background

What is Teviron & Neoron?

In 1938, a Japanese company called Teijin, a billion dollar fibre, plastics, and pharmaceutical conglomerate founded since 1918, began research into fibres that can generate negative static charge beneficial to health.

This led to Nefful (founded in Japan in 1973) the world’s market leader in Negative Ion Clothing. Teviron, invented in 1956 after 18 years of research, is the commercial name of the fibre that creates high negative static. Born after years of further research and development, Neoron is the next-generation negative static fabric with the same functionality with brighter colours and softer texture.

Japan, a country where its people have the highest life expectancy than any other country in the world, according to the CIA World Fact book is consistently ranked as one of the healthiest nations in the world with many innovative products that improve health and extend lifespan.

Previously, Teviron was only available to the citizens of Japan. In other words, if you were to visit Japan and wanted to buy Teviron clothing, you would need to have a valid Japanese ID in order to qualify to make a purchase! Today, Nefful has 6 global offices and independent distributors in more than 20 countries. 

The technology to produce the Teviron and Neoron fibre is very complex and weaving the fibre into each article of clothing takes anywhere between 3-6 months. All Teviron and Neoron negative ion clothing are still made ONLY in Japan and is GUARANTEED that the standard of quality is maintained (especially since the unique fabrics are not the easiest to work with due to their very soft texture).

The uniqueness of Teviron and Neoron:

  • Excellent Heat Regulation 

  • Superior Moisture and Water Permeability 

  • Safety / Non-inflammability

  • Generates High Density of Negative Ions


Excellent Heat Regulation

Teviron, in comparison to some of the more common fibres such as wool or cotton, excels in keeping our body temperature at the 98.6ºF (37ºC) so that it doesn’t fluctuate with the changes in our environment. This is very important in keeping us warm and prevention from getting sick.

In the chart below, Teijin Ltd. Osaka Research Center tested temperature differences between covered and uncovered parts of the skin on subjects. Axis Y represents temperature differences; Axis X represents room temperature.

While each material didn’t show great differences less than 25°C (perfect for warm summer temperatures and hot countries near the equator), but as the temperature dropped, especially at -5°C, showed significant differences. Teviron has shown excellent temperature preservation as the temperature drops.

This is why Teviron undergarments were chosen by the famous Japanese Mountaineer Team to the Himalayas and also by a group of Japan challengers to the Arctic Circle. If undergarments and bedding do not provide sufficient heat insulation, we will feel icy cold, causing blood vessels to constrict, restricting the nutrients and oxygen sent out to the cells.


Superior Moisture and Water Permeability 

Superior water permeability allows moisture to be wicked away from the body, and quickly evaporates therefore keeping one dry and comfortable. Teviron is a material that does not absorb ANY moisture. In other words, 0% liquid absorption.

Without this type of technology, one’s skin will remain wet, which can increase the sensation of being cold. This also causes the constriction of one’s blood vessels which in turn will restrict the nutrients and oxygen sent to the cells of the body.

The below chart is Teijin’s experiment result. It shows when we perspire, cotton will absorb the moisture and makes one feel sticky or uncomfortable; however, Teviron’s absorption is zero, so perspiration can be vaporized quickly, leaving one dry and fresh.

The below chart is another of Teijin’s experiment report. A person was wearing specialized garment (half side cotton and the other side Teviron), the report shows humidity rate after test subject did some exercise and was perspiring. On the cotton side, it took 40 minutes to restore dryness. On the Teviron side, it only took about 10 minutes; which shows superior moisture and water permeability.

The below chart is a research report done by Carl Marx City Fiber Engineering Institute in East Germany. It shows that during the same time frame, Teviron’s transfusion of liquid is apparently higher than other fibres and perspiration can vaporize rapidly. Only Teviron has this outstanding moisture and water permeability feature.


Safety / Non-inflammability

Teviron is recognized by the Japanese Fire Retardant Association as a fire retardant product simply because of its low flammability consisting of non-inflammable content, making it very safe to use. It has a very high burning temperature which is measured by LOI (Limited Oxygen Index).

If the LOI of a material is less than 24, it would make it highly flammable. The LOI of cotton is 19-21, wool is 24-25 while Teviron’s LOI is much higher at 35-37. Teviron has a burning temperature of 503ºC (937.4ºF) compare to wool at 500ºC (932ºF).

A person was reportedly able to escape a burning home in Japan by covering herself with a Teviron blanket as she dashed out of the house.

**It is important to note that the fire retardancy is only applicable to Teviron and not other materials that may be blended into the clothing or bedding products.

Fire Resistance Association
Fire Resistance Association


Generates High Density of Negative Ions

In this test conducted by Japan’s “Fibre Industry Testing Institute”, a comparison was made between major fibres’ electrostatic to prove Teviron carried negative charges.

When Teviron rubs against other materials or skin, it generates negative ions proven to beneficial for health.