Parylene vs Traditional Coatings: Which is Right for You?

October 2, 2025 Parylene

When it comes to protecting sensitive electronics, medical devices, and mission-critical components, the choice of coating can define long-term performance. Two common options are Parylene coating and traditional conformal coatings such as acrylics, silicones, and urethanes. Each offers unique benefits — but which is right for your application?

For an overview of vapour-deposited protection and where it fits within modern electronics manufacturing, see our Parylene coating solutions.

What Makes Parylene Different?

Parylene is applied using a vapour deposition process, producing a pinhole-free, highly uniform film that coats every exposed surface — including hidden spaces and complex geometries.

This process helps deliver:

Exceptional moisture barrier performance
Ultra-thin yet durable protection
Strong resistance to chemicals, solvents, and temperature extremes

Because it forms a truly conformal layer, Parylene is often selected where reliability cannot be compromised.

Our Parylene coating services are used where uniform coverage, low thickness, and high reliability are critical.

Where Traditional Conformal Coatings Excel

Traditional conformal coatings are typically applied by brushing, spraying, or dipping. They remain highly effective in many environments and offer practical advantages such as:

Faster application and curing (process dependent)
Lower cost compared to Parylene (in many cases)
Easier rework and repair during production

For applications where cost sensitivity or rapid turnaround is key, traditional coatings can be the most commercially sensible option.

For applications where cost, speed, or rework access are priorities, our liquid conformal coating solutions remain a highly effective option.

Making the Right Choice

The right choice depends on your environment and performance requirements. If your device must endure harsh conditions or complex 3D coverage requirements, Parylene coating can provide unmatched protection. For less demanding applications, traditional conformal coatings may strike the best balance between performance, reworkability, and budget.

The right choice depends on environment, geometry, and compliance requirements, which is why many manufacturers engage our coating services for application-specific guidance and discuss the options.

SCH Services Ltd: Your Coating Partner

At SCH Services Ltd, we provide both Parylene and liquid conformal coating solutions — helping you select the right option for your project. Whether you need high-performance protection or cost-effective coverage, our expertise ensures your product is protected for the long term.

Learn more: Parylene coating services

Parylene coating providing invisible protection for electronic components against moisture and environmental damage

The Hidden Protector: How Parylene Safeguards What You Don’t See

September 29, 2025 Parylene

When it comes to protecting modern electronics and critical components, the greatest threats are often the ones you cannot see. Microscopic cracks, invisible moisture, and environmental contaminants all pose silent risks to performance and long-term reliability. This is where Parylene coating excels — acting as an ultra-thin, invisible shield that delivers durable, long-term protection.

Learn more about SCH Services’ specialist Parylene coating services here.

The Power of Parylene Coating

Unlike traditional conformal coating methods that are brushed, dipped, or sprayed, Parylene is applied using a specialised vapour deposition process. This process allows the coating to polymerise directly onto the surface, forming a uniform, pinhole-free layer that fully encapsulates components.

The result is a truly conformal barrier that coats not only visible surfaces but also sharp edges, internal geometries, and hidden crevices that liquid-applied coatings often struggle to reach.

Invisible Moisture Protection

Moisture remains one of the leading causes of electronic failure. Even minimal condensation can lead to corrosion, leakage currents, or short circuits. Parylene provides exceptional moisture resistance by forming a continuous microscopic film that significantly reduces water vapour ingress.

This makes Parylene particularly effective in harsh, humid, or environmentally demanding applications where traditional coatings may degrade or fail over time.

Why Industries Rely on Parylene

Industries such as aerospace, automotive, medical devices, and consumer electronics rely on Parylene because of its proven performance and reliability. It is lightweight, chemically resistant, biocompatible, and stable across a wide temperature range — making it suitable for applications where failure is not acceptable.

SCH Services Ltd – Your Partner in Invisible Protection

At SCH Services Ltd, we specialise in both liquid and Parylene conformal coating services, providing tailored solutions to meet specific environmental and performance requirements. Whether protection is needed against moisture, chemicals, or long-term environmental exposure, Parylene offers reliable defence against unseen threats.

Because in many applications, the best protection is the protection you never notice.

For detailed information on Parylene coating capabilities, applications, and process control, visit our Parylene coating services page.

Comparison between liquid conformal coating and Parylene vapour deposition on electronic assemblies

What Is Parylene Coating and Why Is It Different From Other Conformal Coatings?

September 15, 2025 Parylene

In electronics and advanced manufacturing, protecting sensitive components from moisture, chemicals, and environmental stress is critical. Conformal coatings play a vital role in ensuring long-term reliability, but not all coatings perform in the same way. Among available technologies, Parylene stands out as a unique and highly effective solution.

What Is Parylene?

Parylene is a family of thin, transparent polymer coatings applied using a chemical vapour deposition (CVD) process. Unlike liquid conformal coatings that are sprayed, brushed, or dipped, Parylene is deposited as a vapour inside a vacuum chamber. This enables it to coat all exposed surfaces — internal and external — with a uniform, pinhole-free film.

The most common Parylene variants include:

Parylene N – Excellent dielectric properties, often used in high-frequency applications.
Parylene C – The most widely used type, offering strong moisture and chemical resistance.
Parylene F (AF-4) – Enhanced high-temperature and chemical resistance.

How Parylene Differs From Other Conformal Coatings

Application method – Vapour deposition in a vacuum environment ensures even coverage without pooling, meniscus effects, or edge build-up.
Coverage – Parylene penetrates tight gaps, coats under components, and reaches complex geometries that liquid coatings cannot.
Film properties – Ultra-thin (typically 1–50 µm), transparent, flexible, and biocompatible.
Performance – Superior resistance to moisture, chemicals, and many extreme environments.
Cleanliness – A dry, solvent-free process that leaves no residues, making it ideal for medical, aerospace, and high-reliability electronics.

Where Is Parylene Used?

Medical devices – Catheters, stents, pacemakers, sensors, and implantable electronics.
Aerospace and defence – Flight electronics, sensors, and mission-critical systems.
Automotive – EV electronics, sensors, and ADAS components.
Consumer electronics – Wearables, IoT devices, and microelectronics.

Why Choose SCH for Parylene?

At SCH Services Ltd, we combine over 30 years of coating expertise with a complete Parylene offering that supports both outsourced coating and in-house capability.

Subcontract coating services – ISO-controlled, production-ready Parylene coating.
Turnkey Parylene systems – Complete equipment, dimers, training, and long-term technical support.
Reliable materials supply – Official European distribution supporting quality and continuity.

Whether you need immediate coating capacity or a fully validated in-house process, SCH provides the knowledge, equipment, and materials to ensure long-term success.

If you would like to discuss whether Parylene is the right solution for your application, get in touch with SCH. To explore SCH’s complete Parylene capability, including services, equipment, dimers, and technical support, visit our Parylene solutions page.

Requirements for setting up a conformal coating facility

July 24, 2017 Blog, conformal coating

Conformal coating application and inspection at SCH Services

The set up of a conformal coating production line regardless of the application method has many similar characteristics.

Any coating facility will need the basic requirements put in place that would be standard for any piece of electronic manufacturing process. These include ESD systems, facilities for the machines, the environmental requirements and the normal Health & Safety (HSE) considerations.

Also, the conformal coating production line, whether it is an operator manually brush coating printed circuit boards (PCBs) or an inline robotic spray coating process is typically made up of several stages. These stages are shown below:

Conformal coating process chart illustrating key stages and controls

Not all the stages are mandatory or may be required. However, each should be considered on an individual basis.

Planning to set up a conformal coating facility?

Explore our Conformal Coating Processes Hub and read the detailed guide: How to set up a conformal coating production line. The article covers equipment selection, process flow, quality control and scale-up considerations for reliable, repeatable coating operations.

Prefer to talk it through? Our engineers can review your requirements and help you plan a coating facility that fits your volumes, materials and compliance needs.

Contact SCH to discuss your conformal coating setup ›

Three key points you should know about polyurethane conformal coatings when using them for protecting electronic circuit boards

July 12, 2017 alternative, Blog, conformal coating

SCH Services UK conformal coating facility and operations

A polyurethane (urethane for short and designated UR by IPC) conformal coating is part of the organic family of coating materials that also includes the acrylic and epoxy coatings.

Here are three key facts to consider when examining polyurethane conformal coatings:

Most conformal coatings provide good humidity and moisture protection although some are slightly better in performance than others. UR type coatings are just as good on average as acrylic materials.
A polyurethane coating has traditionally been used to protect electronic circuit boards against chemical attack due to their excellent chemical resistance. This protection allows electronic circuit boards to survive in highly aggressive environments and atmospheres such as the aerospace, military and industrial sectors. However, it does make repair a little more difficult as chemical resistance to a coating means more difficult to remove.
Times are changing and whereas acrylic conformal coatings used to dominate 70-80% of the market, there is a shift in emphasis towards alternative materials due to higher specifications for protecting electronics. Many new conformal coatings (UV cure, two part thin film coatings) now comprise of urethane resin bases and are becoming more popular in high volume sectors such as automotive electronics. This is because the urethane resin lends itself to this type of technology more easily than the acrylic based resins.

Want to find out more about polyurethane conformal coating?

What are conformal coating masking boots and why do they save you money?

July 7, 2017 Blog, masking boots

Conformal coating application and masking process at SCH Services facility

Reusable conformal coating masking boots are a highly cost-effective alternative to traditional masking tape.

Many components on printed circuit boards must remain uncoated during the conformal coating process. The purpose of masking is to prevent migration of coating materials into connectors, contacts, and defined keep-out areas where coating would cause functional or reliability issues.

Custom-made masking boots provide a major labour-saving advantage during both the masking and de-masking stages of conformal coating. Unlike tape-based masking, these boots are fully reusable and are simply fitted over components such as connectors, plugs, and sockets prior to coating.

Reusable conformal coating masking boots can be designed as simple push-fit caps for standard connectors or as more sophisticated custom geometries for complex or high-density assemblies, as shown in the examples below.

They provide reliable, repeatable protection across all major conformal coating application methods, including:

Batch and selective robotic spraying (reducing the need for complex programming)
Vertical and horizontal dip coating
Vapour deposition processes such as Parylene coating

Reusable masking boots used in conformal coating operations at SCH Services

Three reasons to switch from masking tape to reusable masking boots

Switching from tape-based masking to reusable masking boots can reduce total masking costs by up to 80%:

Faster application – masking boots can be applied 4–5× quicker than masking tape.
Faster removal – de-masking boots is significantly quicker and cleaner than removing tape.
Lower defect risk – masking boots are far less prone to leakage, reducing rework compared to tape.

The result is a rapid reduction in labour cost, improved process consistency, and fewer coating-related defects when compared to traditional masking tape methods.

Need expert advice on masking PCBs before conformal coating?

Effective PCB masking is critical to prevent coating ingress into connectors, test points, keep-out zones and mechanical interfaces. Poor masking choices can lead to coating defects, rework, reliability issues and unnecessary cost.

SCH supports customers with practical masking strategies tailored to your assembly, coating chemistry and production volume — from reusable masking boots and tapes to liquid masking systems and process optimisation.

If your assemblies also require preparation before coating, you can learn more about our subcontract PCB cleaning and coating services, or speak directly with our engineers to review your masking and coating requirements.

Contact SCH to discuss your PCB masking and conformal coating needs ›

What are the different methods available for cleaning electronic circuit boards?

June 29, 2017 Blog, conformal coating

SCH Services conformal coating facility and production environment

The topic of cleaning printed circuit board assemblies (PCBAs) effectively before application of conformal coating can be daunting. This is because the process of cleaning circuit boards can be difficult especially with so many variables to consider.

When considering cleaning the circuit you need to assess many factors including:

The board and component compatibility with the cleaning method
The ability of the cleaning method to remove the contamination effectively from the circuit
Any residues the cleaning process may leave behind that may be harmful to the circuit in the long term.
The reasons for cleaning the circuit (e.g. contamination removal, adhesion promotion etc.)?

After considering these factors you can compare with the processes available.

The main methods of cleaning printed circuit boards

The main methods of cleaning used in everyday electronics processing before conformal coating application can include:

Aqueous washing
Semi-aqueous washing
Solvent & chemical washing
Plasma surface cleaning

These processes can be mixed, the method can be varied but the fundamental concepts still apply.

However, whatever method you choose you still have to consider that the key to success in cleaning circuit boards is similar to the success made with conformal coating. You need to match the cleaning process, the cleaning materials and the circuit board together. If you do this then this will give you the best results for cleaning the circuit board assembly.

Want to find out more about cleaning?

Five key facts about Parylene when protecting printed circuit board assemblies

June 20, 2017 alternative, Blog, Parylene

Large industrial Parylene coating equipment featuring KR1200HS and KR1500HSU systems for high-volume medical, aerospace and electronics manufacturing

Here are five key facts about Parylene that are critical in understanding this process:

The Parylene conformal coating process is a very specialised vapour deposition application method using specialist vacuum chamber systems. This differs significantly to all of the other liquid conformal coatings available on the market that are applied by spraying, brushing and dipping.
Parylene coating is completely conformal and uniform to the surface of the Printed Circuit Board (PCB) or product. It is also pinhole free. Therefore, components with sharp edges, points, flat surfaces, crevices or exposed internal surfaces are coated uniformly without voids.
Parylene coating provides an excellent moisture and gas barrier due its very low permeability. This means that electronics circuit boards coated in Parylene generally are more “waterproof” than the same electronics coated in a liquid conformal coating.
Parylene is unaffected by solvents (it has very high chemical resistance) and is very effective against salt attack.
Parylene has excellent electrical properties. This includes having low dielectric constant and loss with good high-frequency properties, good dielectric strength, and high bulk and surface resistance.

Find more in-depth details about Parylene materials, deposition principles, masking methods, thickness measurement and core application concepts at our Parylene Basics Hub now.

Or, if you’re interested in moving towards a Parylene process click through to our Parylene Solutions, Parylene equipment and Parylene subcontract services pages.

Want to find out more about Parylene?

Nexus article on, “Outsourcing your conformal coating project – The key points”

June 8, 2017 Blog, conformal coating

Outsourcing your conformal coating project - The key points on subcontracting to an external company

Nexus, the independent conformal coating resource, recently published an article on subcontracting your conformal coating services out to a third party.

I thought it would be useful to signpost people to this article and republish the points they raised since getting it right can be so critical in outsourcing. Nexus identified that there are, “three key points to consider when choosing a subcontractor“.

These three key areas were:

Quality
Turnaround time
Price

They stated that,

“if you get these three key areas correct then you have succeeded. Everyone will be happy and there are no more problems with conformal coating.”

(Source: Nexus).

However, within each of these areas, they outlined a lot of questions that should be asked to ensure you get it right. Those points were examined in detail with some real insight into subcontract services.

Want to find out more about subcontract conformal coating services?

Find out how we can help you with your conformal coating process now. Contact us now to discuss your needs and let us explain how we can help you.

What is a fluoropolymer nano coating and how can it protect my circuit board?

June 6, 2017 alternative, Blog, Fluoropolymer

What is a fluoropolymer nano coating and how can it protect my circuit board?

A fluoropolymer Nano-coating is an ultra-thin film comprised of fluorocarbons and characterised by carbon-fluorine bonds.

Chemically inert, fluorocarbons are not susceptible to Van der Waals force. This means that films formed using these materials are non-stick (hydrophobic and water repellent) and friction reducing.

Also, due to the fluorine bonds, these Nano-coatings demonstrate a high level of chemical resistance to acids, bases and most solvents. This makes them excellent materials for protecting electronic circuits at certain circumstances.

What properties of the Nano-coatings are used to protect circuit boards?

Fluoropolymer coatings have very specialised properties. However, for electronics the main properties that are useful include:

Being highly hydrophobic (water repellent)
Having a high moisture barrier
Having a high chemical resistance
Having high dielectric properties
Providing high corrosion resistance
Providing good abrasion / wear resistance

These properties are excellent for protecting circuit board assemblies in harsh environments.