Non conductive paint limits the flow of heat or electrical current
Non conductive paint refers to a coating which is a poor conductor of heat or electricity. These coatings are used as electrical or thermal insulators throughout industries – they protect surfaces from overheating and systems from short circuits. In principle, most organic coatings that do not contain metal flakes or have a metallic finish can be used as electrically non conductive paint. For thermal non conductivity, coatings that do not let heat penetrate are used.
In this article we will take a closer look at non conductive paint and its uses as well as the different types of non conductive coating and the possibilities regarding application methods.
4 main types of non conductive coating
Non conductive paint is most often needed on metal surfaces due to metal’s high electrical and thermal conductivity. However, many other substrates such as carbon fibre can be treated with non conductive paint. It is also suitable for concrete, as concrete is slightly conductive and floors require anti static coating in factories and workshops. Non conductive paint for concrete is usually a part of an ESD flooring system which consists of conductive and non conductive coating layers depending on the more specific requirements.
Non conductive coatings exist is various types. Here we will outline the most common ones.
- Polymer coatings – such as polypropylene, PVC and polyethylene are common non conductive coatings in industrial and offshore applications. Next to insulating from electric charge they also have a thermally insulating nature. Therefore, they are suitable for example for pipelines that deal with temperature fluctuation. Yet they, especially PVC coatings, are also common insulators on wires. These are rubber-like thermoplastic coatings.
- Epoxy resin coatings – epoxy is a hard wearing industrial coating which functions as non conductive paint on floors, areas around machinery and on smaller scale in circuit boards of appliances and consumer electronics as a conformal coating.
- Ceramic plasma sprayed coatings – ceramic coatings are the most common means of industrial electrical and thermal insulation in industries such as automotive, aviation and machine building. This non conductive spray coating may also be needed when repairing cars, especially parts exposed to heat.
- Phosphate coating – is a pretreatment non conductive coating for metal used mainly for preventing galvanic action and therefore, corrosion. For the best results a phosphated surface should receive another coat of non conductive paint.
Even though these coatings are used as non conductive paint, some of them can also be modified to increase a surface’s electrical conductivity.
How to choose the most effective non conductive paint for your project
Choosing a non conductive paint or coating is dependent on the nature of your project. The choice between paints (epoxy and polymer) and other coatings (ceramic and phosphate) is rather easy: if long lasting thermal insulation is needed, you should choose for ceramics. If you need a pretreatment for similar purposes, phosphating is a suitable option. Both of these make the surface also electrically non conductive.
When electrical non conductivity is required on metal and other materials an epoxy or polymer coating may be suitable. Polymer coatings are further divided into many types, which makes the choice more difficult. If you are looking for an epoxy or polymer non conductive paint pay attention at least to the following factors.
- Substrate material – not all coatings are suitable for all substrates. Make sure to get a product that is specifically meant for your substrate.
- Environment – exterior or interior? Temperature, exposure to chemicals, abrasion and other hazards all affect the choice of non conductive paint. For example epoxy does not deal well with UV radiation or flexible surfaces, polyurethane has lower chemical resistance than epoxy and acrylics tend to lack durability.
- Application method – only thermoplastic coatings are suitable for dipping metal in fluidised bed, epoxies exist as powders and liquids and PTFE can only be applied as a liquid coating.
- End use – hand tools usually receive a thermoplastic coating, floors make use of epoxy or polyurethane, circuit boards are protected with non conductive spray paint based on epoxy or plastic-like coatings.
Some well known non conductive paint products in the UK
A standard aerosol non conductive coating spray costs about £30,-. Naturally there are also more expensive and higher quality options for both industrial and domestic use. One well known brand in the UK is Techspray which sells non conductive spray paint for electronics and applications alike. Another non conductive coating brand is Electrolube which focuses more on industrial products.
Another known non conductive paint is PlastiDip – especially familiar to those who have ever been busy fixing their computer. PlastiDip is a coating available in different sizes for different prices – from 250 millilitres (about £6.00) to 60 litres (about £830.00). An aerosol spray solution costs about £6.20 for 400ml. PlastiDip is often the go-to coating due to its flexibility, soft touch and comfort, resistant to different weather conditions and functionality between -30°C and +200°C. It is also easy to remove, or peel off of many surfaces.
Find non conductive coating suppliers in the United Kingdom
If you are looking for non conductive coating manufacturers, suppliers or other specialists in the UK, feel free to contact us. Our experts are here to help and happy to assist you in finding the best non conductive paint for your project.