Electronics Cleaning Chemicals: Solving Common Challenges & Their Solutions

Electronic devices require regular cleaning to operate properly and safely, which can be challenging due to component delicacy and the chemical reactions that cause contamination. That’s where isopropyl alcohol for cleaning electronics comes in. It’s a common general-purpose cleaning chemical that rapidly evaporates and can be used to safely clean circuit boards, connectors, and screens.

Explore our guide to learn about using alcohol cleaner for electronics and other cleaning chemicals too.

What are some of the tell-tale signs that your electronics are contaminated? Look out for:

• Poor performance: Dust and grime sticking to electronics dampens current due to increased resistance. This draws more electrical energy and risks malfunctions
• Overheating: Increased resistance generates heat, increasing cooling energy needs and fire risk. Contaminants also prevent heat dissipation and block airflow
• Corrosion: Flux residue and electronics etching chemicals can attract moisture, corroding the metal available to transmit electricity and increasing resistance
• Current leakage or shorts: Ionic contamination creates conductive metal lines (dendritic growth) on printed circuit boards (PCBs). They cause current leakage and eventually short circuits when they reach an adjacent circuit point
• Poor coating adhesion: As with paint, conformal coating can fail to hold in contaminated areas

Isopropyl alcohol for cleaning electronics is a common general-purpose cleaning chemical. It’s a flammable, colourless liquid with a distinctive scent. It easily penetrates dirt, flux residue, and oils on various surfaces — though it can damage rubber and silicone seals. IPA rapidly evaporates, important for electronics since cleaner residues can interfere with signals and cause electrical shorts.

Use IPA for cleaning PCBs, connectors, peripherals, and screens (provided you dilute it 50/50 with water). Its fast drying time makes it a good general-purpose cleaner for expedient cleaning of electronics to minimise downtime.

Is isopropyl alcohol rubbing alcohol? Yes, at 70% strength. Undiluted IPA is not generally safe for home cleaning use, but it’s excellent for cleaning industrial electronics. 

RS stocks IPA tins, pourable bottles, and spray bottles (with straws for precision cleaning). For delicate cleaning, apply IPA using a cotton or foam swab and gently scrub the area.

Contact cleaners are for cleaning dust, grease, dirt, and oxidation from electrical contact points like switches, connectors, relays, circuit breakers, and battery terminals: any sliding electrical contact points that can be disconnected.

A contact cleaner for electronics can be solvent-based or water-based. Solvent-based cleaners have stronger cleaning and quicker-drying abilities but are more environmentally hazardous to dispose of. Simple solvent-based contact cleaners include rubbing alcohol and acetone. Both are effective, quick-drying, and residue-free, but can damage the plastics and seals used to encase electronics.

Speciality electronics contact cleaners can be non-conductive, non-flammable, and even safe for live electronics, though that often carries health and environmental risks. Contact cleaners usually come in spray bottles with precision straw attachments.

Soldering is the joining of electronic contacts, especially in circuit boards. Flux is essential in soldering. What is flux? It’s a chemical applied during soldering to repel oxides, help the solder flow, and make it wet enough to adhere to the metal surface. If flux residue isn’t removed afterwards, it can become acidic and draw in moisture, leading to corrosion.

We offerflux removersin spray bottles, wipes, application pens, and pour bottles, which let you finely apply it using a cotton swab. IPA can also often handle flux removal. You can also clean PCB flux automatically in batches using solvent immersion, ultrasonic cleaning, and water-based flux remover spraying (essentially a PCB dishwasher).

The flux remover strength, cleaning method, and cleaning duration depend on the flux. R, RA, and RMA fluxes come off easiest using standard flux removers or IPA. Cleaning ‘no-clean’ flux or flux from higher-temperature soldering (as with lead-free soldering) requires a stronger remover and additional scrubbing. Aqueous flux can require a water-based flux remover.

The best cleaning chemicals for greases or oils on electronics can be IPA or contact cleaners. IPA-based electronics cleaning solvents may be designed for degreasing specifically. Other IPAs and contact cleaners may be well-suited for removing grease, though ensure they won’t damage the base material.

Vapour degreaser machines are often used in crucial medical and aerospace electronics applications. They use a boiling and condensation cycle. A specialised solvent is heated in a lower sump to create a dense cloud of hot vapour. When cooler electronic parts enter the vapour, the gas condenses on them, dissolving contaminants, which drop off down into a tank. 

Let’s quickly compare these solutions for cleaning electronics:

Harsh solvents can embrittle and crack rigid plastic electronics housings. Products using acetone or toluene can be destructive to acrylic or polycarbonate materials, unlike solvents based on alcohol or hydrocarbons.

Electronics cleaners can also deform or dissolve rubber seals — further exposing the electronics to contaminants. The seal’s material affects how it withstands electronics cleaning chemicals. Rubber and silicone seals are prone to deformation and wear, while Teflon seals fare better.

When introducing electronics cleaning products, thoroughly test their effects on electronic components and their adjacent supporting parts.

Start with compressed air or light brushing to remove most dust and debris. Use short air bursts at a safe distance to prevent damage.

Flux residue removal is essential after soldering work. Use IPA or a PCB cleaning spray meant for flux removal, provided it’s suited for your flux. For stronger fluxes (or large PCB volumes), consider an automated cleaning system that uses solvent baths, ultrasonics, or a spraying cycle.

Flux residue won’t evaporate, though. It needs to be sprayed off the PCB completely or picked up with a swab. Your cleaning work might spread flux residue around and leave trace amounts elsewhere that could still corrode. It’s important to be thorough when removing flux and to inspect the PCB afterwards.

Cleaning corrosion and oxidation are more difficult to deal with. They indicate damage that cleaning can’t fix. You’ll need to neutralise this using white vinegar, potassium hydroxide, or a baking soda paste. Apply gently with a cotton swab, wait a few minutes, and gently scrub the problematic deposits away. Rinse residue with distilled water and then rinse with IPA to rapidly remove moisture (to prevent further corrosion).

For cleaning switches, connectors, or relays, you’ll need a contact cleaner for electronics. Choose one based on what you’re cleaning and its contamination: dirt, oils, greases, or oxidation. Severe cleaning chemicals can damage adjacent plastics, however.

Start by safely disconnecting the power, unless the equipment and the contact cleaner allow cleaning while energised. Use a cotton swab, brush, or lint-free cloth to apply the cleaner and gently rub away contamination.

Apply pressurised contact cleaners gently, increasing pressure gradually, to avoid damaging electrical contacts. Avoid aggressive scrubbing, though wire brushes and sandpaper can be used carefully to break through stubborn corrosion and dirt.

Allow adequate drying time before reconnecting power. Water-based contact cleaners need more drying time, though they can be flushed away with water to help speed things up. 

If you select the wrong cleaner or don’t rinse it away, this can leave residues that cause further damage.

Ionic residues, including the severe white residue, appear due to adverse reactions between the cleaner, the flux, and the base materials. This ionic contamination leads to dendritic growth, current leakage, and short circuits.

Organic residues carry milder risks (mostly aesthetic and coating adhesion ones) and come from improper cleaning techniques or selecting the wrong flux remover.

Test whether a drop of water or IPA dissolves the residue, respectively indicating ionic and organic. Accordingly, choose a strong, compatible water - or solvent-based cleaner. Spray it on, scrub the residue off with a swab or brush, rinse with the same cleaner, and ensure it drains or dries without new residue.

Always consider the health and safety risks of these chemicals.

• Flammability: PCB cleaning sprays, especially IPA, can be extremely flammable. Use them far from sparks and flames
• Inhalation: If you’re experiencing headaches or dizziness, stop using these chemicals and reassess them
• Chemical contact: Wear PPE for your skin and eyes
• Environmental: Electronics cleaners previously depleted the ozone layer due to their Freon content. Since the global phase-out of these substances, you must now check for the cleaners' smog-causing volatile organic compounds and their global warming potential (GWP). To ensure compliance, study the regulations set by the Environment Agency in England (or its equivalents in Scotland, Wales, and Northern Ireland) and adhere to the Fluorinated Greenhouse Gases (F-Gas) Regulation for any residual or substitute high-GWP chemicals

Keep safety data sheets (SDS) and a cleanup plan for each chemical in use.

The rubbing and wiping of electronics during cleaning generates static, and even tiny static discharges can be imperceptible to humans but catastrophic for PCB components. It’s vital to stay grounded while cleaning electronics.

Wear an ESD wrist strap and anti-static gloves, stand on an ESD-safe mat, and use ESD-safe tools, all of which RS stocks.

For every electronics cleaner you select, think about the types of contaminants you need to remove, what the base materials can withstand, how you’ll thoroughly remove the cleaner when you’re done, and the safety and environmental concerns. This will keep your crucial electronics running reliably, efficiently, and safely.