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Super water-repellent material

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HIREC - Hydrophobic Coating Series


Super Water-Repellent Material, HIREC, Drastic reduction of water film attenuation
, Countermeasures against snow and ice related-field troubles

"CountingSheep" The Times Square Show 2011 400KB PDF Download




The super water-repellent material HIREC, developed by NTT Advanced Technology Corporation, is a dramatic new concept in the field of water-repellent materials.

Up until now, water-repellent coatings afforded a maximum contact angle between an object and water droplets of approximately 100°. The Super Water-Repellent Material HIREC provides a contact angle of 150° or more, resulting in higher performance and long-term stability. On top of that, this breakthrough coating also demonstrates superior effectiveness in preventing adhesion of snow, ice, and other substances besides water. The Super Water-Repellent Material HIREC is expected to contribute to higher performance and durability, while maintaining the attractiveness of products in a wide range of fields, particularly communications equipment.

Powerful water-repellent properties that fend off water


The most important feature of the Super Water-Repellent Material HIREC is that it keeps water away. Super water-repellent properties are completely different from the properties of waterproofing that prevent water from permeating. HIREC repels water and shows excellent water-repellent properties with a contact angle of 150° or more between an object and water droplets. When water droplets fall on HIREC-coated surfaces, they instantaneously disperse into smaller droplets, as if they are repelled. The water droplets remaining on the coated surfaces are round and maintain a spherical shape as if they are standing-up. These excellent properties of HIREC are expected to bring a wide range of benefits to various industries and everyday life.

Watch water being repelled below.
Water flowing into a HIREC-coated sink model.

Windows Media Video(4.9MB)

  Coated HIREC on the tea strainer.

Windows Media Video(42.2MB)


"Snow and ice adhesion resistant properties" reduce adhesion and prevent the formation of icicles

The Super Water-Repellent Material HIREC is effective in preventing snow and ice from sticking to surfaces and is also effective in preventing the formation of icicles. In snowy regions where snow and ice cause hazardous conditions, the super water-repellent material HIREC can be counted on as a very effective solution.



Selected to match your use, HIREC Series brings a new level of higher performance.

A broad lineup of high repellent HIREC has been developed for a wide range of uses and applications. You can select the product that best meets your needs.

Troubled by water, snow, ice or icicles? We can propose new preventative measures for you.

( 2 coat type )

HIREC100HIREC 100 contains a small amount of titanium dioxide, which serves as a photo-catalyst, keeping coated surfaces like new. With this antifouling character, deterioration due to air pollution is greatly reduced. The recommended coating thickness is approx 30 µm and the repelling character will be maintained for approx 3 years. The coating is opaque. (can be colored)

Object Purpose Data
Water Snow Ice •Antenna (parabola, radome, etc.)
•Steel mast
•Radar etc.
•Requires undercoating(30µn;m) •Film thickness:30µn;m •possible coating area:
3m2/kg by air spary
5m2/kg by brush

HIREC 1100

HIREC100Touch-up Spray for HIREC 100.

For touch-up of HIREC100

Object Purpose Data
Water Snow Ice For the easy touch-up of HIREC 100 Net:220ml

(1 coat type)

HIREC100 As HIREC 450 has high adhesion to a wide range of materials, the base coat isn't required. It is very effective to prevent the accumulation of ice. The coating is semi-translucent white.
( HIREC 450 has no antifouling character, so the repellent characteristic will be reduced if the surface deteriorates.)

Object Purpose Data
Water Snow Ice •Antenna (parabola, radome, etc.)
•Plastic (acrylic, ABS, etc.)
•Metal (except copper)
•Undercoat not required
•Film thickness:15µn;m
possible coating area:6m2/kg by air spary


HIREC100 For touch-up of HIREC450
(The spray gas has been changed to LPG. )

Object Purpose Data
Water Snow Ice For the easy touch-up of HIREC 450 Net: 145ml



Examples of Applications

Demonstration [1] Water can be dipped using a tea strainer.

DemonstrationWhen water was poured into a tea strainer coated with this super water-repellent material, it was evident that the water remained in the strainer.

Demonstration [2] HIREC easily separates oil and water.

DemonstrationWhen the solution of oil and water (separated with the oil floating above the water) was poured into a tea strainer coated with the super water-repellent material, the oil went through the tea strainer first. Afterwards, when water was poured into the tea strainer, the water remained in the strainer. This demonstrates that HIREC can easily separate oil and water.

Demonstration [3] HIREC easily distinguishes the water level of a river.

DemonstrationThe water level of a river was being observed from a short distance, photographed and monitored with a wooden measuring device. Monitoring is generally carried out using an infrared camera so that it can be done at night. In clear weather, the surface of the water can be easily identified since the temperature of the water and the temperature of the water level is different. However, in rainy weather, identifying the water level is difficult. When the measuring device gets wet, its temperature becomes almost the same as the temperature of the water level. This condition is shown in the uncoated plate on the right side of the following thermo image. The plate on the left side, which was coated with HIREC did not get wet in the rain due to its water-repelling properties. The water temperature and the temperature of the water level measuring device were different, enabling identification of the water level inside the red circle.

<< Optical image >> << Thermo image >>
Demonstration Demonstration
Left:a HIREC-coated plate
Right:an un-coated plate


Demonstration [4] HIREC's Insulating Properties.

Demonstration When a HIREC-coated copper wire was immersed in water, it was unaffected by the resistance of water.

When two copper wires were affixed to a glass plate coated with HIREC and immersed in water, the space between the copper wires exhibited no change in resistance. The space was tested using a mega-ohm-meter (resistance-measuring device.)

For example, when HIREC is coated over a printed circuit board, it prevents insulation degradation due to condensation, etc.

* HIREC's insulation properties are above 1,000 mega-ohms.



Handling of HIREC Spray

Handling instructions 125KB PDF Download
Handling points 84KB PDF Download
Spraying time and coating intervals 89KB PDF Download