You are here

What is a coating?

A coating is a covering that is applied to the surface of an object. The purpose of applying the coating may be decorative, functional, or both. Coatings are ubiquitous and can be found on walls, furniture, on all sorts of wires and printed circuits, the outside of houses and cars, and much more. In addition, the decorative duties of coatings span quite a broad spectrum.

Decorative coatings are mainly used for their color, texture or other visual property. Functional coatings are applied to change the surface properties of the substrate, such as adhesion, wettability, corrosion resistance, wear resistance and more. In some cases, the coating adds an entirely new property such as a magnetic response or electrical conductivity and forms an essential part of the finished product.

Coatings may be used in various processes, that are roughly divided into: vapor deposition, spraying, chemical and electrochemical techniques, roll-to-roll coating processes and other, less prominent techniques.

What is graphene?

Graphene is a two dimensional layer of carbon atoms, arranged in the form of a honeycomb lattice. It is touted as a “miracle material” because it is endowed with an abundance of astonishing traits - this thin, one atom thick substance is the lightest, strongest, thinnest material known to man, as well as the best heat and electricity conductor ever discovered - and the list does not end there. Graphene is the subject of relentless research and is thought to be able to revolutionize whole industries, as researchers work on many different kinds of graphene-based materials - each one with unique qualities and purpose.

Graphene structure photo

Graphene for coatings

The vast selection of extraordinary properties that graphene possesses can open the door to many interesting types of coatings, paints, inks and more. Graphene's high resistivity can make for durable coatings that do not crack and are resistant to water and oil; its excellent electrical and thermal conductivity can be used to make various conductive paints, and a strong barrier effect can contribute to extraordinary anti-oxidant, scratch-resistant and anti-UVA coatings.

Graphene enables a wide array of functional coatings and paints, for many possible applications. Among these can be high performance adhesives enabled by graphene's high adhesion property, anti-bacterial coatings, solar paints (capable of absorbing solar energy and transmitting it), paints that provide isolation for houses, anti-rust coatings, anti-fog paints and UV ray blockers, non-stick coatings for various domestic applications (like frying pans and countertops) and even a much-hyped possibility (currently under scientific examination) of a coating that turns a regular wall into a screen.

Commercial activity

Graphene-enhanced products are yet to reach widespread commercialization. Nonetheless, given graphene’s impressive array of properties and the vigorous R&D that is taking place, graphene-enhanced coatings should not be too far away.

The Sixth Element Materials, a Chinese company that focuses on R&D, mass production and sales of graphene and related materials, showcased its graphene-zinc anti-corrosion primer used for offshore wind power tower, that can come at a competitive price compared with zinc rich epoxy primer.

Garmor, the University of Central Florida spin-off formed to develop a new graphene oxide flakes production process, has developed graphene oxide-based coatings useful for limiting UV radiation damage to sensors and polymers. Garmor's transparent GO-films are reportedly derived from a commercially-viable and scalable process that can be readily implemented with minimal constraints.

Garmor GO coating imageFour layers of GO coating on polycarbonate

The Spain-based Graphenano announced the launch of a graphene-based series of paints and coatings called Graphenstone in 2014. These are said to be very strong and also acts as a protective layer against environmental damage. Graphenstone is made from a graphene powder and limestone powder.

Graphenstone cans photo

The British Electro Conductive Products released a sprayable transparent conductive coating based on a CNT and graphene platelets (GNP) hybrid material. TBA are targeting the food, electronics, pharmaceuticals and petrochemicals markets.The new ATEX-compliant product is available as a clear, anti-static aerosol, and it should also be available as bulk paint. Its application will safeguard electronic equipment used in explosive environments and bring it up to European standards.

Further reading

Latest Graphene coating news

A new graphene oxide coating to improve the performance of lithium-sulfur batteries

Mar 21, 2017

Researchers at Yale University have developed an ultra-thin coating material, based on graphene oxide, that has the potential to extend the life and improve the efficiency of lithium-sulfur batteries. The newly developed material is a dendrimer-graphene oxide composite film, that can be applied to any sulfur cathode.

GO coating to improve Li-sulfur batteries performance image

The researchers state that sulfur cathodes coated with the material can be stably discharged and recharged for more than 1,000 cycles, enhancing the battery’s efficiency and number of cycles. In addition, they said “the developed film is so thin and light it will not affect the overall size or weight of the battery, and thus it will function without compromising the energy and power density of the device”.

Thomas Swan launches a high-performance graphene intermediate product for coatings

Mar 15, 2017

Thomas Swan logoThomas Swan has announced the launch of a high-performance graphene intermediate product for coatings formulators. The new Elicarb Graphene product is a cost effective, stable, easy to handle dispersion of Elicarb Materials Grade Graphene powder for formulation into epoxy-based coating formulations. The product is available now in liter quantities for testing and evaluation.

Thomas Swan has established a 20 tonne per year capability for the manufacture of Elicarb Graphene and Elinova Boron Nitride products at its UK manufacturing site in Consett, County Durham. Elicarb Graphene Epoxy Dispersion is a high performance intermediate product which is intended for further optimization and incorporation into customers’ existing proprietary coating systems. The graphene dispersion is targeted at improving corrosion resistance, thermal conductivity, chemical barrier and mechanical resistance in industrial coatings.

Graphene Batteries Market Report

Applied Graphehe Materials updates on progress of its graphene work

Mar 05, 2017

Applied Graphene Materials logoApplied Graphene Materials, in a recent update, said it made "significant progress" in all of its core markets of composites, coatings, oils and lubricants. Among the reported highlights of its work is its graphene-enhanced epoxy prepreg system MTC9800 to be shown at the JEC World exhibition later this month, after a year and half collaboration with SHD Composites.

In addition, the company has recently completed the first phase of a development project investigating the application of its graphene for resin infused Aerospace structures. During 2016 it continued work on its development program with Airbus Defence and Space, a division of Airbus Group SE, although details of this work are still subject to a non-disclosure agreement.

Graphene coating on copper wires may help prevent electromigration and help minimize future electronics

Feb 21, 2017

As electronics keep shrinking in size, several problems arise. One of these is that the copper wires that connect transistors to form complex circuits need to be very thin, but carry so much current that can cause them to break apart due to atoms being knocked out of place. One way of solving this, studied by a group led by Stanford University, is to wrap copper with graphene. The group found that this can alleviate this major problem called electromigration.

stanford team solve electromigration problem with graphene coating image

This was presented at a recent IEEE meeting that addressed the coming problems for copper interconnects and debated ways of getting around them. Growing graphene around copper wires can help prevent electromigration, and also seems to bring down the resistance of the copper wires. Generally speaking, the narrower the wire, the higher its resistance. “Interconnects have had to shrink while increasing the current densities by 20 times,” said Intel Fellow Ruth Brain at the meeting.

Grafoid develops GPURE Graphene-based membrane technologies for industrial markets

Feb 19, 2017

Grafoid logoGrafoid has announced the development of the GPURE Membrane Platform, consisting initially of six next generation GPURE Graphene-Polymer membrane technologies intended for industrial markets.

GPURE Graphene-Polymer membranes include:

  • GPURE (A) - A high performing, free-standing membrane developed for water desalination applications
  • GPURE (B) - A stable, large area membrane developed for wastewater filtration suitable for very high temperature operating applications
  • GPURE (C) - A large area free-standing membrane developed for water filtration pre-treatment and may be suitable for use in gas separation applications and may be used as a lightweight component for automotive and sports equipment applications
  • GPURE (D) - A large area membrane that may be used for gas separation and sensing applications
  • GPURE (E) - A large area membrane intended for use in gas separation applications
  • GPURE (F) - May be applied as a graphene varnish for wood surfaces to protect against moisture, UV light and high temperatures