Our thoughts and comments on the carpet cleaning industry.
Wednesday, June 05, 2019
What are in all these carpet cleaning detergents, anyway, and what do they do?
What are in all these carpet cleaning detergents, anyway, and what do they do?
Chemical Ingredients in Carpet Cleaning Detergents
Here is a list of the most common chemicals used in carpet cleaning detergents in alphabetical order:
Alkaline builders
Anti-caking agents (powders)
Anti-redeposition agent
Bleaching agents
Corrosion inhibitors
Coupling agents
Dyes
Emulsifiers
Encapsulating Agents - Crystallizing chemicals
Enzyme
Fillers - water, if it’s a liquid cleaner; salt or salt cake if it’s a powder.
Foaming or defoaming agents
Fragrance (perfume)
Optical brighteners
pH Buffers
Preservative
Sequestering agents (water softeners)
Solvents
Surfactants
Thickening agents (liquids)
Hot Water Extraction Cleaning (“steam cleaning”) detergents fall into two obvious categories: powder and liquid. Powders are usually more effective cleaning agents with lower use cost than liquids, while liquids are more easily formulated for lower pH and are more easily handled, but are usually mostly water. All other things being equal, the higher the pH, the better the cleaning; the lower the pH, the better the stain removal. Bane-Clene’s LCA®-256 is a true neutral pH detergent. PCA™ Formula 5 has the lowest pH of our powders (9.2 at 0.4 oz./gal.), yet is a better detergent for most applications due to its higher level of Emulon®. For strictly commercial work, PCA™ Formula 4, with its pH of about 11 at 0.4 oz./gal., is even more effective.
Alkaline builders control the pH for best cleaning. They include the following:
Soda Ash (Sodium Carbonate):
Most powdered cleaning agents contain high levels of soda ash because it’s cheaper than most water-soluble alkaline builders.
But, Soda ash reacts with calcium water hardness to form Calcium Carbonate scale. This scale can clog nozzles, scale up the stator (resulting in failure) and leave the carpet fibers dull from a hazy film.
Soda ash is primarily used to cut costs and absorb liquid ingredients such as surfactants.
There is no soda ash added to PCA Formula 5 or PCA Formula 4.
Sodium Bicarbonate (baking soda):
Sodium bicarbonate is sometimes used in milder, near neutral powdered detergents. This is seldom used in carpet cleaning detergents.
Borax:
While borax may be found in some laundry detergents, I’ve never seen it used in carpet detergents because it’s not very soluble in water.
Sodium Metasilicate:
Sodium Metasilicate has a very high pH (over 12) in water and imparts corrosion inhibition to aluminum.
It is commonly used to make the detergent effective against cooking grease by saponifying the grease (turning it into soap).
There is no silicate added to PCA Formula 5, PCA Formula 4, Preface® traffic lane spotter or Olefin Preconditioner.
But, it is a very important ingredient in Super LCA™ and TLS® 2000 for greater effectiveness against heavily soiled carpet and greasy restaurant carpets. TLS 2000, a liquid high-pH pre-spray, contains sodium metasilicate and a solvent to help cut through cooking grease in restaurants. The pH of TLS 2000 at its recommended concentration is about 13, so it is definitely not intended for use on stain-resist residential nylon or on upholstery. However, it is extremely effective in cutting through the stubborn oils so often attached to olefin (polypropylene) fibers. We specifically designed TLS 2000 for restaurant carpets with heavy grease and other problem commercial carpets.
But, Sodium Metasilicate has some drawbacks. It reacts with water hardness to form a scale similar to that from soda ash,is much finer and is not easily removable with acid. Affected parts and nozzles frequently must be replaced rather than simply cleaned. It dissolves very slowly which can lead to clogging of the unit.
Phosphates:
Trisodium Phosphate, Disodium Phosphate, Tetrasodium Pyrophosphate and Tetrapotassium Pyrophosphate are very soluble high pH builders and grease cutters that also increase cleaning power to carpet cleaning detergents.
Anti-caking agents:
Anticaking agents are additives placed in powdered or granulated materials, such as powdered detergents and even table salt and baking powder to prevent the formation of lumps (caking).
Without anticaking agents, a powdered detergent can quickly turn into a hard block that’s hard to dissolve.
Anti-caking agents include sodium aluminosilicate, calcium carbonate, calcium silicate and precipitated silica products.
Anti-redeposition agents
A good detergent has to contain suspending agents or anti-deposition agents which keep the soil particles “suspended” in the detergent solution until the solution is pulled out of the carpet by the vacuum and air movement action.
Without good suspension, you will frequently have streaking, resulting in having to go back and reclean.
An oxidizing bleach is a chemical that gains electrons and causes the oxidation of another substance. That is, an oxidizing bleach removes color by adding oxygen (or chlorine) to a dye structure.
Examples of oxidizing bleaches are hydrogen peroxide, chlorine bleach (sodium hypochlorite), sodium perborate, sodium persulfate and sodium percarbonate.
Sodium persulfate and sodium percarbonate are the most common bleaches added to powdered detergents. They help remove stains and brighten the fabric. Powders containing oxidizing bleaches must be kept from moisture when not in use.
A reducing bleach is a chemical that loses electrons and removes oxygen from a compound.
Examples of reducing bleaches are sodium thiosulfate (photographer’s hypo), titanium stripper, sodium bisulfite and sodium hydrosulfite.
Reducing bleaches are often used in upholstery and rug “shampoos” to remove “yellowing” and to prevent “browning” of sensitive wool and cotton fibers.
Corrosion inhibitors:
Corrosion inhibitors are sometimes added to detergents to prevent corrosion of aluminum, steel and brass parts.
The most common corrosion inhibitor used is sodium metasilicate which also serves as an alkaline builder as mentioned earlier.
Corrosion inhibitors for brass, such as Benzotriazole and Amino-Alcohols, are sometimes added to detergents.
Coupling agents:
One of the problems in formulating a liquid detergent is that the chemist is putting incompatible ingredients that hate each other in a concentrated form in water.
Without a “coupling agent,” the liquid detergent will separate into layers. In some detergents, if you heat up the concentrate, you will see this occur.
The most common coupling agents are sodium xylene sulfonate and its relatives and phosphate esters.
Coupling agents rarely contribute to cleaning power.
Dyes:
While very rarely added to powdered detergents, dyes are normally added to liquid detergents.
The primary practical reason to add a dye to a detergent is to alert the user which product they are using. Sometimes we’ll hear a carpet cleaner tell another cleaner to go get the “green” or the “blue” stuff out of the van!
The biggest problem with dyes is that they can be unstable and lose their color, especially when exposed to heat and light.
Emulsifiers:
Emulsification is the process of removing those oils that do not saponify; i.e., they don’t react with alkali and turn into soap.
These oils are are motor oils, exhaust fumes, common pollution oils, lubricants, silicones, furniture polish, sun tan lotion, tobacco smoke residue, lubricating grease, oils from skin and pet hair, etc.
Emulsifiers are molecules that are also “surfactants” covered in more detail later in this article.
Emulsifiers help remove oils into water because they have two “ends” on the molecule. One “end” loves water and the other “end” loves oil.
The oil-soluble end of an emulsifier penetrates into the oil with the water-soluble portion sticks out into the water. Hundreds of these molecules surround this oil particle, break it into smaller particles and pull it into the water by changing the very nature of both the water and the oil.
A familiar example of an emulsion would be salad oil. If you mix vinegar and oil, you get two layers. No matter how hard you shake it or heat it, it separates into two layers! Yet, you can go to the grocery store and find all kinds of salad dressings that don’t separate! Why? An emulsifier is added!
The emulsifier Bane-Clene uses in most of its carpet cleaning detergents is Emulon®.
Encapsulating agents or crystallizing agents:
Crystallizing agents are added to some detergents to reduce resoiling of the carpet after cleaning.
Resoiling agents are usually resins such as styrene maleic acid derivatives or polymers.
What most people mean by “resoiling” is that the carpet became visibly dirty more quickly than it should have after it was cleaned.
Encapsulants prevent re-attachment of soil to carpet fiber during the extraction cleaning process. During the drying process, they combine with any remaining wicking residue to form non-sticky crystal structures.
Bane-Clene supplies three encapsulating products from Pro's Choice:
Protease enzymes are added to some detergents and traffic lane spotters to help remove fatty soils such as cooking grease. They are useful in cleaning restaurants.
Enzymes act as “catalysts” to help break down organic material for easier removal.
There are six basic types of enzymes for cleaners:
Protease - degrades protein based soils
Amylase - degrades starch based or carbohydrate soils
Cellulase - breaks down cotton fibers to release soils
Lipase - degrades fat-based soils
Mannanase - degrades food-based stains and
Pectinase - degrades fruit-based stains
Bane-Clene supplies two cleaning products containing enzymes:
Pro-Zyme+ Grease Digester and Protein Prespray for restaurant, kitchen, dining room carpets and
If the detergent is a liquid, it is mostly water - which does nothing! That’s why powdered detergents are more economical.
Fillers used in powders do not contribute to cleaning but add “bulk” making you think you have 20 pounds of detergent when you really only have 10 pounds.
Examples of powder fillers are salt (sodium chloride) and salt cake (sodium sulfate).
Fillers are not used in any of the Bane-Clene powdered cleaners.
Foaming or defoaming agents:
FOAM is a common problem in extraction carpet cleaning. Foam in the vacuum hose can increase drying time and greatly reduce cleaning effectiveness because it has, in effect, reduced the vacuum hose to 1/2 inch in diameter! Additionally, excessive foam can cause damage to the vacuum pump and other equipment.
Silicone emulsion defoamers are sometimes added to carpet cleaning extraction detergents to counteract the foaming properties of the emulsifiers and surfactants used.
Carpet shampoos, which are discussed later in this article, must be very foamy and have very stable foam. The most common ingredient is sodium lauryl sulfate, a very sticky compound.
Fragrance (perfume):
Fragrances, obviously, do not contribute to cleaning, but they can leave the room smelling “clean and fresh”.
Except for anti-allergen cleaning products, fragrances are nearly always in the formulas of carpet cleaning detergents and, quite often, the cleaning technician may add a separate fragrance to the cleaning solution.
Bane-Clene does supply Per-Scent® fragrance that can be added to the cleaning solution.
Optical brighteners are added by some manufacturers who don’t know that carpet manufacturers don’t approve of carpet cleaners containing optical brighteners.
Optical brighteners are highly specialized dyes which absorb invisible ultraviolet light and re-emit it as visible light, making the carpet appear brighter than it really is.
They are used by some carpet cleaning chemical manufacturers who don’t realize that their use will permanently cause the carpet to turn yellow. Since these are dyes, there is no cure for this problem.
Bane-Clene has NEVER used optical brighteners in its products.
pH Buffers:
The purpose of pH buffers is to help the cleaning solution maintain its pH level as its alkaline ingredients are neutralized by acidic soils.
Most of the “alkaline builders” covered earlier serve also as pH buffers.
Preservative:
Preservatives are chemicals added to some detergents to inhibit bacterial and fungal growth.
Microbial contamination in a cleaning product can lead to a number of problems including the development of “off-odors”, development of “off appearance” including color changes and opacity changes, and loss of performance.
Preservatives are more commonly used in near neutral household detergents than higher pH commercial products.
Paraben preservatives are found in nearly of cosmetics.
Benzisothiazolinone is the most commonly used preservative in cleaning products, usually around 0.1-0.3% concentration.
Sequestering agents:
Sequestering agents or chelating agents (water softening agents) are needed to keep the detergent more active in hard water and to help prevent scaling and clogging due to hard water.
Sequestering agents essentially surround the calcium and magnesium ions in hard water to keep them from keeping the detergent from working effectively and prevent “soap scum” film.
Virtually all carpet cleaning products contain chelating agents.
One drawback to sequestering agents is that they also “love” copper and brass and shorten the life-span of your brass fittings.
Additionally, since marble and limestone are calcium carbonate, detergents containing high levels of water softeners will dull marble and limestone floors and countertops.
The most common chelating agents used in carpet cleaning detergents are sodium citrate, EDTA (ethylene diamine tetraactic acid), NTA (Nitrilotriacetic acid) and Polyphosphates.
Solvents:
The most common solvents used in liquid carpet cleaning products are Butyl Cellosolve, Butyl Carbitol, Citrus, Propylene Glycol Ether and M-Pyrol.
Butyl Cellosolve is a water-soluble solvent that attacks both water-soluble soils and water-insoluble oils and greases and has a very characteristic odor that most users find irritating.
Butyl Cellosolve is a unique solvent that is soluble in water yet is so strong that it is commonly used in wax strippers, heavy-duty ready-to-use cleaners, all-purpose cleaners, degreasers, wax strippers, bath and tile cleaners and most window cleaners.
Additionally, some prespray additive products, such as Energy Prespray Solvent Booster from Pro’s Choice may contain aliphatic solvents such as mineral spirits.
Surfactants:
Surfactants (surface active agents) are the raw materials which really make the detergent work and are are the most important ingredient in detergents.
Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids (such as between a cleaning agent and oil) or between a liquid and a solid (such as dirt).
In wet extraction cleaning, speed of action, emulsification and good wetting are essential.
Additionally, the surfactants used must be low foaming.
Ethoxylated Alcohol, Alkyl Phenoxy Polyethoxy Ethanols and Alkyl Glucosides (made from oils and sugar) are the most common “nonionic” surfactants and Linear Alkyl Benzene Sulfonate (LAS), Sodium Lauryl Sulfate and Sodium Laureth Sulfate are the most common “anionic” surfactants.
In anionic surfactants, the head of the molecule is negatively charged. This particular type of surfactant is very good at removing oily dirt and stains unless used in very hard water. The minerals keep the anionic surfactant from working properly.
With hard water, better cleaning results are with non-ionic surfactants. These surfactant molecules have no electrical charge.
Frequently, anionic and nonionic surfactants are used together in a cleaning product to complement and boost cleaning action.
Surfactants allow water and grease to mix
Surfactants: are wetting agents that lower the surface tension of a liquid and lower the interfacial tension between two liquids.
Each surfactant molecule has a hydrophilic (water-loving) head that is attracted to water molecules AND a hydrophobic (water-hating) tail that repels water and simultaneously attaches itself to oil and grease in dirt.
With anionic surfactants, the head is negatively charged. This is the most widely used type of surfactant for laundering, dishwashing liquids and shampoos because of their excellent cleaning properties.
Non-ionic surfactants do not have an electrical charge, which makes them resistant to water hardness deactivation. They are excellent grease and oil removers. The most commonly used non-ionic surfactants are ethers of fatty alcohols.
The primary surfactant used in Bane-Clene products is Emulon®.
Thickening agents:
Thickening agents are sometimes added to make the liquid detergent seem more concentrated than they really are.
How do the ingredients in carpet shampoos and dry foams differ from those used in warm water extraction? Carpet shampoo products must have the following characteristics, which dictate their ingredients:
Very high foam levels to reduce wetting.
Very stable foam.
High lubricity to reduce damage to the carpet fibers from the brushes.
Dry to a non-sticky residue (in theory).
Therefore, a carpet shampoo must contain a very foamy chemical as its main ingredient. The most common is Sodium Lauryl Sulfate. Sometime when you’re taking a shower or bath, take a look at the ingredient statement on your hair shampoo bottle. It will say “Contains Sdium Lauryl Sulfate, Sodium Laureth Sulfate” or something similar.
Sodium Lauryl Sulfate and its relatives , Sodium Laureth Sulfate (SLES), and Ammonium Laurel Sulfate (ALS) exhibit a very high and very stable foam. They are very poor detergents (would you want your hair shampoo to be a heavy-duty industrial strength butyl degreaser?). The problem is that they dry to a soft, sticky residue that causes resoiling. Because of the resoiling problem, carpet shampoos will also have an anti-resoiling additive such as a resin, but these additives only reduce rather than eliminate resoiling. Because shampoos are actually poor detergents and, basically, simply bury the dirt, they frequently contain high levels of optical brighteners. They may contain solvents such as alcohol or Butyl Cellosolve.
TLS® 2000 Heavy-Duty Carpet Cleaning Prespray / Traffic Lane Spotter.
Free Bane-Clene Information Package
Free packet of information about Bane-Clene can be obtained by calling toll-free 1-800-428-9512 (U.S. ONLY!). Your information packet will include a full color catalog and price addendum. Packets will arrive in approximately 2 weeks through standard United States Mail.
Author: Donald W. Terry, Sr., Bane-Clene’s Chemist
Date Published: June 5, 2019
Revised by Don Terry: June 5, 2019
VIDEO: Bane-Clene Carpet Cleaning Detergents and Emulsifiers
Presented by Bane-Clene’s chemist, this video shows how PCA Formula 5, Booster and Per-Scent are used in a Bane-Clene truckmount carpet cleaning machine for the best carpet cleaning you’ve ever seen.
Free packet of information about Bane-Clene can be obtained by calling toll-free 1-800-428-9512 (U.S. ONLY!). Your information packet will include a full color catalog and price addendum. Packets will arrive in approximately 2 weeks through standard United States Mail.
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