What’s the difference between a nano-ceramic and a nano-coating?

Simon Mercer talks through the basics of silicon dioxide-based nano-coating technology and how it’s used to extend the serviceable life and looks of many surfaces

As nano-coatings grow in popularity and availability in numerous sectors, the term “nano-ceramics” has entered the space – particularly in association with the automotive sector, where these terms are often interchangeable. So, what is a nano-ceramic, what are their benefits and how do they sit within the nano-coatings category?

Nanotechnology was first researched in 1959 and became a practical engineering science in 1981. Over the past 40 years, it has been rapidly developed for use in a wide range of different industries such as aerospace, communications, and more recently antibacterial applications. In fact, many of us come into contact with nanotechnology coatings every day without realising.

The glass industry was one of the first to seize upon the advantages of ‘easy clean’ and the dirt repellent benefits that nano-coatings offered end-users as a way to differentiate their products. Now much of the shower glass sold in the UK will have been treated with a nano-coating; the effect can be seen in the beading/shedding of water and prevention of limescale adherence.

Coatings have been developed to ease cleaning and maintenance in many areas of life. Within the urban environment, they have been developed to preserve and protect some of our oldest stone buildings from weathering and environmental pollution, maintaining these structures for future generations. They can also provide graffiti and chewing gum resistance to more modern concrete structures – allowing both to be removed relatively easily, reducing the need for harsh chemicals.

Nano-coatings are not just used to protect hard surfaces such as granite worktops, car bodywork or glass, they are also used to protect fabrics – extending their serviceable life with stain resistance and water repellence. These are performance features that we are most familiar within our everyday lives when we purchase sofas, carpets and coats.

In short, nano-coatings offer a wide range of benefits to many industries, in general, reducing wear and tear, cleaning time and expense as well as extending the functional life of surfaces.

In a time when the word ‘nano’ has become a fashionable marketing prefix to describe phones, computers and even a cryptocurrency, what does it have to do with coatings? To begin to understand nanotechnology and the dimension of coating finishes it can create, the first hurdle is comprehending the size of the molecular structures that are used. These are measured in nanometers (nm), typically silicon dioxide-based nano-coatings are approx. 120 mn, this is around 80,000 times thinner than human hair; as a visual guide, a piece of paper is nearly 100,000 nm thick.

Nano-Care coatings are based on nanoscale molecules of silicon dioxide (Si02), hydrogen and nitrogen. State-of-the-art technology combines these elements to produce a ‘glass-like coating’ that can adhere to natural, synthetic or metallic substrates. The coating becomes part of the substrate – enhancing performance and delivering new functionality to the surface.

In many instances, the new or enhanced functionality is often the ability to repel liquids/water, dirt, scratches and resist UV radiation. Due to the permanent and inert nature of the coatings’ bond to the surface, they are highly abrasion-resistant. For any such coating, mechanical, weathering and abrasion resistance information should be readily available, ideally to an ISO standard.

From this first generation of silicon dioxide-based technology, an innovation through the addition of nano-scale ceramic particles which have been combined with the base active ingredient has been commercialised – and it is this group which are described as, and are true ‘nano-ceramics’.

These offer enhanced ‘hardness’ to the protective layer; this is measured on the Moh scale of mineral hardness rated 1-10 (as for pencils). These coatings are designed to prevent scratches and to maintain the aesthetics of the original surface. They are commonly used within the automotive and transport sectors to maintain bodywork and interior surfaces against everyday wear and tear.

The following summarises the main key features of nano-ceramics:

• Non-stick: water and dirt repellence offers long-term protection and facilitates cleaning
• Graffiti and stain protection: barrier properties of ultra-dense ceramic and quartz structures protect from dirt and contamination ingress
• Scratch protection: surfaces are more resistant to wear and tear
• Corrosion prevention: ultra-density halts rust at source.
• UV-protection: anti-aging preserves valuable surfaces
• High temperature resistance: No change in characteristics under intensive heat (up to 1000 degrees)
• The perfect finish: Colour enhancements and gloss bring outstanding aesthetics to surfaces
• Easy-to-apply: Perfect finish is achieved without the need for special training

While the terms ‘nano-coating’ and ‘nano-ceramic’ may be used interchangeably in marketing material, the bottle never lies, a true nano-ceramic will always have the following characteristics due to the chemical constitution:

• Ammonium hydroxide smell – Polysilazanes can only be manufactured using it
• Sensitivity to humidity – they react with air humidity to create a chemical bond
• Sold in pressure-resistant aluminium or glass bottles
• No ethanol solvent odour – this is used in silane or polysiloxane technology with only a fraction of the durability and protection

A nano-ceramics coatings’ ability to preserve the functional life of a surface is a benefit that is coming more to the fore with the drive for greater sustainability within manufacturing processes and extending the usable life of products; while also reducing the need for costly replacements or environmentally damaging cleaning solutions.

Simon Mercer is with Signo-Nanocare UK Ltd.