So, what is a surfactant?

Surfactants are substances that when added to a liquid, reduce its surface tension. Detergents are one type of surfactant, and when they are added to liquids, they increase its spreading and wetting properties. Basically, surfactants make water “wetter,” making it better able to penetrate and lift away grime and dirt from surfaces.

Detergents, like Dawn Dish Soap contain a surfactant, or mixture of surfactants, which lowers the surface tension of a liquid.

If you are using a home brew cleaner for your Ultrasonic, keep reading.

Surfactants Make Cavitation More Effective in Ultrasonic Cleaners

To begin with, let’s take a brief look at how ultrasonic cleaning operates. This cleaning technique uses a piezoelectric transducer to generate vibrations. This generates ultrasonic sound waves that travel through a liquid bath.

When ultrasonic waves move through water, they cause the liquid to rapidly alternate between expansion and compression. During the expansion phase, which is also referred to as the “rarefaction cycle,” small vacuum bubbles are created, which then violently collapse when the rarefaction cycle ends.

These vacuum bubbles are known as cavitation bubbles, and they are the driving force behind ultrasonic cleaning.

As these cavitation bubbles violently implode, they discharge streams of plasma at velocities exceeding 500 miles per hour. These streams then remove and agitate the oils and dirt particles on the surface of the watch parts being cleaned without causing harm to the surface underneath.

How Surfactants and Ultrasonic Cleaning Work Together

Increasing cavitation levels enhances the cleaning power by reducing surface tension. Adding a detergent to the ultrasonic cleaner, which is typically water based, amplifies the efficiency of the ultrasonic cleaning process.

Professional Ultrasonic cleaning solutions lower surface tension in cleaning tanks by using surfactants. This enables small bubbles to hold more energy and makes ultrasonic cleaning more efficient. Since surfactants are formulated to lower surface tension instead of breaking chemical bonds, they are generally mild and environmentally friendly.

Therefore, using a detergent that contains surfactants is recommended.

Here are some common detergents that contain surfactants

Tide: Tide is a popular laundry detergent that contains a variety of surfactants, including linear alkylbenzene sulfonates (LAS) and alcohol ethoxylates.

Gain: Gain is another laundry detergent that contains surfactants, including LAS and ethoxylated fatty acids.

Dawn: Dawn is a dishwashing detergent that contains surfactants, including alkyl sulfates and ethoxylated alcohols.

Palmolive: Palmolive is another dishwashing detergent that contains surfactants, including sodium lauryl sulfate and alkyl ether sulfates.

All: All is a laundry detergent that contains surfactants, including LAS and alcohol ethoxylates.

Persil: Persil is a laundry detergent that contains surfactants, including LAS and alcohol ethoxylates.

Seventh Generation: Seventh Generation is a brand that makes a variety of cleaning products, including laundry detergent and dishwashing detergent, that contain surfactants such as sodium lauryl sulfate and alcohol ethoxylates.

These are just a few examples of common detergents that contain surfactants. There are many other brands and products that also use surfactants in their formulas.

Types of Surfactants that can be used in Ultrasonic Cleaners

  1. Alkylphenol ethoxylates (APEs): APEs are non-ionic surfactants that are commonly used in ultrasonic cleaners. They are effective at removing a variety of contaminants, including oils, greases, and waxes.
  2. Sodium dodecyl sulfate (SDS): SDS is an anionic surfactant that is commonly used in ultrasonic cleaners. It is effective at removing proteins, oils, and other organic compounds.
  3. Polyethylene glycol (PEG): PEG is a non-ionic surfactant that is effective at removing a wide range of contaminants, including oils, greases, and particulate matter.
  4. Ethanolamines: Ethanolamines are a class of surfactants that are effective at removing a variety of contaminants, including oils, greases, and inorganic salts.
  5. Citric acid: Citric acid is a mild acid that can be used as a surfactant in ultrasonic cleaners. It is effective at removing mineral deposits and other inorganic contaminants.

When choosing a surfactant for use in an ultrasonic cleaner, it’s important to consider factors such as the type and amount of contaminants to be removed, the type of object being cleaned, and the specific cleaning performance requirements. It’s also important to follow the manufacturer’s instructions for adding surfactants to the ultrasonic cleaner, as improper use can lead to reduced cleaning performance or equipment damage.