top of page
Gentoo logo.png


Gentoo is an advanced protective coating that offers durability and chemical resistance. It is easy to apply and clean, and can withstand even the toughest environments. With its exceptional wear resistance, high performance, low sliding angle, and flexibility, Gentoo outperforms other coatings.

Gentoo is a transparent coating that repels not only water and oils, but also acids and bases. This makes it a great choice for protecting against corrosion, enhancing wear resistance, and creating an effective barrier against chemical damage.

What is Gentoo?

Galvanic corrosion, also known as "different metal corrosion," occurs when different materials come into contact underwater. This causes one metal to corrode faster as the anode, while the other corrodes more slowly as the cathode, even if both metals wouldn't corrode on their own. It is a common and highly destructive form of corrosion.

To combat corrosion, including galvanic corrosion, NanoTech Solutions Norway has developed a sol-gel technology called Gentoo. Gentoo is a durable, transparent, and hydrophobic coating that acts as a thin repellent and barrier. It provides corrosion protection by creating a dense barrier and repelling water from the coating's surface. Despite its thinness (4-6 microns on average), Gentoo is extremely hard, flexible, and offers exceptional protection.

The hydrophobic surface treatment is a transparent coating made of a hybrid organic-inorganic matrix that uses silane-modified polymer chemistry. This treatment combines the benefits of organic polymer coatings, such as flexibility, impact resistance, durability, abrasion resistance, corrosion protection, and UV resistance, with a low surface energy to enhance hydrophobicity.

This ultra-thin coating system, with a thickness of less than 5 μm, can be applied to various surfaces including painted, untreated metallic, and polymer surfaces. It can be applied using common techniques such as flow coating, brush, or spray. Despite being transparent, the hydrophobic treatment does not alter the appearance of the surface it is applied to. Instead, it enhances water repellency, improves corrosion resistance, withstands mechanical wear and impact damage, reduces salt accumulation, and resists weathering over time.

The request concerns:

Preparation of coatings and data

Gentoo is a straightforward, transparent coating system that has self-orienting fluorine groups on its surface. These fluorine groups are securely bonded into the coating and offer long-lasting water-repellent properties. The good news is that the low concentration of fluorine groups needed for this hydrophobic effect does not affect the adhesion to the surface.

The hybrid nature of Gentoo also includes silane functionalities, which allow for strong bonding between the coating and the surface substrate. This results in excellent adhesion to metallic, treated, and painted surfaces. The organic component of Gentoo adds flexibility and durability to the coating system. All these features work together to create a highly durable coating with outstanding water-repellent properties and abrasion resistance. You can find more details about the key attributes of this hydrophobic coating system in Table 1.

Table 1

Key features of Gentoo


Hydrophobicity and runoff

Corrosion protection

Flexibility and durability

Thickness and weight


Environmental durability

> 110 ° contact angle and <5 ° runoff angle.

Excellent water repellent properties. Reduces corrosion and extends the life of metal components.

Shows excellent flexibility via a tough cross-linked polymer matrix and durability.

The surface treatment is extremely thin (1-5 μm) and light.

Robust adhesion to metallic (aluminium, steel, etc.) substrates, glass, polymer (acrylic, polycarbonate) and paints (polyurethane, latex, acrylic).

Excellent resistance to degradation due to salt spray and UV exposure.


Apply in a single coat using spray, flow or brush methods with minimal surface preparation.

Material properties

Stability for storage



Heat resistance

Stripping stability

Wear and tear


Wet tape paint (adhesion)

FOD or tile resistance

Weather resistance

Water resistance

Chemical resistance

Test method

ASTM D1200

MIL-PRF-32239, 85285;



ASTM D2244, D522,


MIL-PRF-32239 med 

Cee Bee A-235

ASTM D1044, D2486

ASTM D3359

ASTM G154 Cycle 2 QUV-B,




fuel JP-8


Minimum 4 hours

6-12 months, 1.67 - 46.1°C;

37.8, 25, 4.4°C @ 3 months. ea.

Contact angle 105 + 3°;

Drainage 10 + 2°

No cracks

ΔE <1.0, no cracks after

1 h at 121.2°C


5B at 6H hardened or

mechanically ground and complete

hardened paint

Identical or better than


1000 hours with Dgloss <20,

DE <1.0

No effect

No / minimal effect,

better than control


PASSPORT; 6 hours at 23.9°C

PASS; 12 months


PASS; 1/4 "mandrel; cracks

on 1/8 "with paint, but no cracks on Gentoo

PASS; No change CA / WS, gloss or DE

PASS; Cee Bee A-235 stripper








Δ Transparency <5%

Δ Dis <3%

(per 150 cycles)

HSS Common Test Protocol,

ASTM D3359

5B at RT, 49 ° C at 96 hours

and 65 ° C at 168 hours

ASTM D3170,

corrosion evaluation TBD

Pot life (after mixing)

Gentoo properties
Shelf life
Physical properties
Fluid resistance

In connection with these tables, Gentoo has been applied by flow, spray or dip method on the following substrates; Glass, polycarbonate, acrylic, silicone, Nitronic® 50 stainless steel, aluminum alloys, anodized 7075-T6 aluminum, Alodine® and 316 stainless steel.


Treated substrates were air-cured at room temperature (~20°C) or cured at 90°C for 15-60 minutes, depending on application requirements. Coating thickness was measured at 4-6 μm depending on the substrate and application method. Three samples were used for each test and the results were the average of the tests.

Hydrophobicity and transparency

Gentoo's hydrophobic properties and light transmission properties when applied to glass substrates, are shown in Table 2. The treatment shows contact angles of > 110° and an average runoff angle of ~ 3-11 °, depending on water droplet size. Gentoo does not affect the transparency of the substrate, and shows negligible haze and maintains 100% clarity.

Table 2

Hydrophobicity and transparency of coatings


Contact angle

Runoff angle (120 μL drop)






6 °

3 °


Runoff angle (50 μL droplet)

Transparency (%)

Glass substrate
Glass substrate with Gentoo
Test method

Chemical resistance

Gentoo was also rated for liquid resistance when applied on MIL-PRF-23377 epoxy primer with MIL-PRF-85285D gray urethane lacquer, LHE Zn-Ni coated 4130 steel panels according to MIL-PRF-85285D liquid immersion testing and High-strength Steel Joint Test Protocol. For MIL-PRF-85285D liquid penetration testing, coated panels are cured, stored in a desiccator for at least 16 hours, and weighed before immersion in the following solvents for 7 days at 37.8°C: Flight-de-icing / Anti-icing liquid (SAE AMS 1424 ), cleaning agent (degreaser), aerospace equipment (MIL-PRF-87937) and paint remover, PR-3500 epoxy paint remover.

Glass substrate

121 ± 3°C (250 ± 5°F)

66 ± 3°C (150 ± 5°F)

Room temperature

24 hours

24 hours

7 days

Table 3

MIL-PRF-85285D - Test fluids and conditions


Lubricating oil (in accordance with


Hydraulic fluid (in accordance with


JP-8 fuel (in accordance with


Liquid temperature
Immersion fluid
Time of immersion

Gentoo showed no blistering or coating failure and maintained hydrophobic performance after immersion in anti-icing fluid, cleaning agent (degreaser), lubricating oil, hydraulic fluid and JP-8 fuel. 


Gentoo was removed using PR-3500 epoxy paint remover, as planned. Commercially available superhydrophobic coatings were also evaluated, and those coatings lost all superhydrophobic and hydrophobic performance after immersion in all liquids, and were completely removed when immersed in most liquids, with the exception of anti-icing fluids. 

More information about Gentoo

Gentoo provides significant extra compared to other competing coatings with a hydrophobic effect. Especially when evaluated with standardized accelerated corrosion test methods and chemical resistance. Download the reports using the links below (eng).

bottom of page