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 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.
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.
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.
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.
The latest graphene coating news:
UK-based cycling brand AbsoluteBlack has added a new graphene chain lube product to its portfolio, which comes with considerable promises of efficiency, impressive watt savings, and a rather high price.
The cycling brand's newly developed hydrocarbon lubricant contains graphene, and AbsoluteBlack claims that its formulation has outstanding durability per application, delivering reduced friction for prolonged periods of use.
Graphene supplier and product manufacturer Nano Graphene (d/b/a GrapheneCA) has announced that its antibacterial products have shown to be 99.9% effective in making various surfaces bacteria proof according to ASTM E2180 testing protocol for determining antimicrobial activity of polymeric materials. This follows GrapheneCA's April 2020 launch of its online store to sell these new “Dr. Nano” anti-bacterial coatings.
GrapheneCA’s Dr. Nano Flooring and Dr. Metal product lines have been shown in an independent laboratory test to provide exceptional antimicrobial protection of different surfaces. The coatings demonstrated exceptional activity against gram-positive and gram-negative, antibiotic-resistant bacteria that can cause severe respiratory infections, among other things. The proprietary formula in the graphene-improved, water-based epoxy coatings blocks the metabolism of microorganisms by restricting cellular respiration and cell division on surfaces.
Nano Graphene, AKA GrapheneCA, an engineering and technology company offering graphene based products and solutions, has announced the launch of its online store to sell its new “Dr. Nano” anti-bacterial coating. GraphenCA did not openly specify that this is a graphene-based product, but we assume so as GrapheneCA is a developer of graphene-based products.
Dr. Nano is a formula developed to create anti-viral environment that would protect different surfaces for a time frame of 7 to 10 years.
Patrick Franz, the founder and chief executive of materials group PlanarTECH which is currently engaged in an equity crowdfunding campaign to expand its business and enter new markets, sees graphene as a potentially useful tool in the fight against Coronavirus.
Franz says research papers written in China over the last four years identified graphene oxide as a potentially effective anti-viral agent. Though none of the studies targeted the same pathogen responsible for the current Coronavirus outbreak, Frantz says the conclusion is that graphene oxide may offer a platform to fight a variety of viral infections (such as the SARS-CoV-2 coronavirus) and possibly in the form of a coating.
Oxford Advanced Surfaces (OAS) and 2-DTech (a Versarien subsidiary) has signed a collaboration agreement to develop a new range of products that incorporate graphene, into OAS’ proprietary Onto chemistry platform. OAS says these materials will enable it to enhance the mechanical performance and electrical and thermal conductivity of its products.
OAS says that its Onto chemistry platform delivers a range of versatile and reliable chemical surface treatments that are used to improve the adhesion of paints, coatings and adhesives to composite materials and engineering plastics. OAS aims to introduce a range of new products enhanced with graphene to address a wide range of applications and new materials challenges encountered in both its current and potentially new markets.