Dry cleaning solvents and fluids: An introductory guide

Very briefly, there are 5 major components to a dry cleaner’s service: cleaning, finishing (aka pressing), inspecting, repairing and packaging.

Other than pre-spotting (that is, targeted stain removal by a skilled technician prior to cleaning a garment in a dry cleaning machine), the dry cleaning solvent or fluid used in the cleaning process is probably the most critical part of the cleaning component.

There are primarily 5 dry cleaning solvents or fluids in use today:

Perchloroethylene (aka perc)

Perchloroethylene, a chlorinated solvent, is the most common dry cleaning solvent in use today. Used by approximately 70% of the 26,000 cleaners in the USA, perc (brand name: Dowper from Dow Chemical and PerSec from Occidental Chemical) is valued for its grease-cutting properties.

Any uniform rental operation specializing in auto repair shops would definitely want to clean in perc.

In recent years, perc has been attacked by governmental agencies, scientific bodies and environmentalists as a potential human carcinogen as well as a ground water and air pollutant. Perc is scheduled to be phased out in California in 2023.

By contrast, advocates for perc have argued that perc, used in accordance with existing environmental laws and regulations, is perfectly safe.

The debate over perc is on-going and contentious with a wealth of scientific and anecdotal evidence supporting both sides of the debate.

But health and environmental safety is not our beef with perc.

Our concern is that perc is a relatively fabric aggressive, dye stripping solvent. Way too damaging for the bespoke, made-to-measure, designer, high fashion, specialty and couture garments in which we specialize.

Synthetic petroleum

About 20% of cleaners use synthetic petroleum, a hydrocarbon solvent that’s a byproduct of the manufacture of gasoline (brand name: DF 2000 from Exxon Mobil Chemical or EcoSolv from Conoco Phillips Chemical).

Synthetic petroleum is often falsely marketed as an “organic, green, non-toxic and environmentally friendly alternative to perc”.

Here’s why synthetic petroleum should never be considered organic, green, non-toxic and environmentally friendly:

While synthetic petroleum is relatively more gentle than perc, it is, nonetheless, subject to the same federal, state and local environmental laws and regulations as perc, both in how it’s used and how it’s disposed of.

From a health and environmental point of view, hydrocarbon dry cleaning solvents are volatile organic compounds (VOCs). VOCs contribute to the formation of ozone, which, in turn, has been linked to various respiratory complications.

Many cleaners that use synthetic petroleum like to refer to themselves as “organic cleaners”.

They argue that synthetic petroleum is technically "organic" because it contains carbon.

But nuclear waste and coal slurry are also technically “organic" because they contain carbon and no rational individual would argue that nuclear waste and coal slurry is “organic”.

There is a whole lot of irony here as well.

Many cleaners who have converted from perc to synthetic petroleum love to malign perc: “We use synthetic petroleum, the good cleaning solvent, not perc, the bad cleaning solvent.


Here’s what dry cleaners who use synthetic petroleum don’t want you to know: If synthetic petroleum can be called “organic” just because it contains carbon, then perc can also be called “organic” because it too contains carbon.

And here’s what dry cleaners who use synthetic petroleum can’t answer: If synthetic petroleum is “organic, why is it subject to the same federal, state and local environmental laws and regulations as perc in terms of how it’s used and how it’s disposed of?

To suggest that synthetic petroleum is organic in the same way that a fruit or vegetable is organic is deceptive and misleading.

Actually, it’s more than that.

It’s a scam, a fraud and a hoax on the general public.

Formaldehyde dibutyl acetal

Coming soon.


Fewer than 5% of all cleaners use siloxane (brand name: Green Earth from General Electric Silicones, Dow Corning Silicones and Shin Etsu Silicones).

Siloxane is

  • Completely odorless and dermatologically friendly.

    You can even (legally) wash your face and hands in it.
  • Extremely gentle.

    So gentle, in fact, that it’s been used for decades as a base ingredient in many personal care products you drip into your eyes and rub into your skin on a daily basis. Such as shampoos, antiperspirants, deodorants and moisturizing creams. Even lipsticks.
  • Chemically inert.

    Which means that siloxane won’t “bleed” or “fade” your colors.
  • Non-toxic.

    Actually, it’s much more than just environmentally friendly. It’s biodegradable.
  • Environmentally benign.

    In the event of a major spill, siloxane degrades quickly in the environment into silica and trace amounts of water and carbon dioxide.

Contrast this to perc, synthetic petroleum or formaldehyde dibutyl acetal.

In the event of a major spill, a cleaner using siloxane will need a bucket and a mop. In the event of a major spill, a cleaner using perc, synthetic petroleum or formaldehyde dibutyl acetal will need to summon your local Fire Department’s Hazardous Materials Unit.

From a health point of view, first aid measures for siloxane state that no action is required when siloxane comes into contact with skin or is inhaled or ingested. This differs markedly from first aid measures for perc, synthetic petroleum or formaldehyde dibutyl acetal solvents (typically, wash, flush and consult a physician).

Pure liquid carbon dioxide

At room temperature and normal atmospheric conditions, carbon dioxide (CO2) is a colorless and odorless gas. When subjected to high pressure in a closed vessel such as a high pressure dry cleaning machine, CO2 transforms into a liquid. This is the principle behind CO2 cleaning.

Although CO2 is a naturally occurring and generally benign substance, there's only a handful of CO2 installations in North America. And the remaining installations are quickly disappearing.

That’s because

  • the acquisition cost of a CO2 machine is relatively high (about 2 to 3 times the cost of a similarly-sized perc, synthetic petroleum, formaldehyde dibutyl acetal or siloxane machine)
  • the cleaning performance is relatively poor (CO2 is a good rinse but removes next to no soil or stains)
  • the environmental impact is not as advertised (a CO2 machine releases 6 to 10 pounds of CO2 into the atmosphere at the end of each cleaning cycle).

From an environmental point of view, pure liquid carbon dioxide is a volatile organic compound (VOC) that contributes to global warming.

Another problem is that it’s cost prohibitive to operate a pure liquid carbon dioxide dry cleaning machine. So much so that the only manufacturer of pure liquid carbon dioxide dry cleaning machines has been a no show at every dry cleaning trade show for at least the past 10 years.

Other solvents

Every few years, another company starts promoting a new solvent that, according to their literature, "is going to revolutionize the dry cleaning industry". These solvents typically go through a familiar cycle: Hype, low to zero adoption, disappearance.

Accordingly, any discussion of these alternative solvents and solvents is beyond the scope of this Position Paper.


Let’s not forget that water is the oldest “solvent”. Water is often used in combination with dry cleaning to ensure that both water-based and soils and oil-based stains are removed from garments and household textiles.

Today, this water-based process is often called wet cleaning.

It is important to note, however, that wet cleaning is not “washing”.

Even the most technologically advanced home washing machines or professional shirt washers cannot match the capabilities of today’s specialized, computer-controlled wet cleaning equipment, where micro-processors control water temperature, cylinder speeds, mechanical action and moisture removal.

What does all this mean for you?

Now that you know the specific solvents or fluids used in dry cleaning today, it’s important to find out 3 things from your cleaner:

  • What specific dry cleaning solvent or fluid does your cleaner use?
  • What are the specific properties of that solvent or fluid?
  • What is the impact of the specific solvent or fluid on your fine garments and household textiles?

In answering these questions, forget about popular terms such as natural, sustainable, biodegradable, non-toxic, essentially non-toxic, practically non-toxic, EPA approved, non-regulated, non-ozone depleting, ozone friendly, ozone safe, VOC free, environmentally friendly, environmentally safe, environmentally preferable, environmentally superior, earth friendly, earth safe, eco friendly, eco safe, green, organic, alternative, or any other similar name your dry cleaner and/or his advertising agency can conjure up.

A ton of words that, in most cases, mean absolutely nothing.

It’s important to recognize that many cleaners use these terms to intentionally confuse or obfuscate, not to educate or enlighten. That many cleaners are purposely ambiguous about the dry cleaning solvent or fluid they use (they just don’t want you to know). And that some clean in perc and claim to clean in synthetic petroleum, while others clean in perc or synthetic petroleum and claim to clean in siloxane.

To discover this for yourself, view the website of any cleaner and try to identify the specific solvent or fluid used by that cleaner. We’d bet that 9 times out of 10 it’s undisclosed.

Now, ask yourself why?

There’s an even better way to identify the specific solvent or fluid used by a dry cleaner. Every county has an air quality control department (or similar entity) that regulates the use of perc, synthetic petroleum and formaldehyde dibuyl acetal solvents by dry cleaners in that county.

Call them and ask for a copy of your dry cleaner’s operating permit. The solvent they use will be right there – in black and white. (In the metro Phoenix area, call the Maricopa County Air Quality Department at 602-506-6201).

By the way, you won’t find our permit on file at the Maricopa County Air Quality Department.

As a dry cleaner who uses siloxane dry cleaning fluid, we’re exempt from all permitting, inspecting and record keeping requirements.

Knowing the specific solvent or fluid used, it's specific properties and it’s specific impact is critical to cutting through the fog of confusing terms in the dry cleaning marketplace.