Soap Vs Detergent : What is the difference?

Why use soap instead of detergent for cleaning?

When I first got into the laundry soap business with my husband, I kept referring to it as laundry detergent. Each time, I referred to the soap as detergent, my husband would interrupt me and say, “Tess, it’s a soap not a detergent.” Well, that baffled me a bit because I didn’t really see why the distinction mattered. In my research, I realized that soap and detergent have been used interchangeably for decades, when in fact, they are quite different from each other.

Soap Vs detergent: What’s the difference?

The simple answer is a soap is made out of fats, oil and water while a detergent is a synthetically produced surfactant. A better answer would be soap is made from organic chemicals and detergents are made from inorganic chemicals.

But, the most important answer would be an explanation of the way soaps and detergents work. Soaps react differently with dirt and oil molecules in water than detergents. While detergents bond with oil and grease molecules by pulling at them, soaps cause an acid-base reaction by breaking down dirt and grease molecules into fatty acids. Since, soap particles dissolve into ions, it makes it easier to penetrate deeper into fabric and completely dissolve any dirt particles. This makes soap a better cleaning agent than a detergent. Furthermore, a soap is eco-friendlier because it is biodegradable and does not contain toxic chemicals.

Another factor for consideration is the Ph (Potential of Hydrogen) level of soaps and detergents. Detergents cause an imbalance in Ph levels. Letting it sit for extended periods of time on skin or clothes absorbs natural oils causing dryness and damage to our skin.

These distinctions are important because it greatly helps us from being victim to the numerous ‘green-washing’ marketing out there. For example, Charlie’s Soap has no soap! Nor are its ingredients as ‘natural’ as they claim to be, buts that’s a topic for another post.

Back to soap and detergents.

The first synthetic detergent was formulated by German chemists during the First World War because they were falling short of soap making supplies. This idea was brought to America by Robert Duncan, a process engineer working for Procter and Gamble. P&G invested in this research to formulate synthetic ‘soap’ because they realized that hard water, found mainly in mountainous regions, interfered with the cleaning process of soap and left residue on the clothes. Dreft was first introduced by Procter and Gamble in 1933. After some research and development, they added ‘builders’ to the ‘surfactant’, preservatives for a longer shelf life and artificial fragrance to hide its peculiar smell. The initial Dreft formula was highly inadequate and would not clean heavily soiled clothes. Cleverly, it was marketed as a detergent made especially for ‘delicate clothing’ and ‘baby laundry’. It took chemical engineers at P&G more than 13 years to come up with a better formula a.k.a. Tide. This breakthrough was made by adding Sodium Tripolyphosphate, an inorganic chemical we now know contaminates our water, is toxic to aquatic organisms and is an allergen which causes breakouts of hives and skin rashes on sensitive skin.

Today, soaps are better cleaners than detergents because of the lower amount of suds or foam they produce. High efficiency washers require a low sudsing cleaning agent. Apparently, in the 1960’s, widespread use of detergent led to piles of discolored detergent foam rising eight feet high at the foot of the Niagara Falls. In short, for all intents and cleaning purposes, a good soap is all that is needed to cut grease, remove stains and live a non-toxic life.

References

http://www.acs.org/content/acs/en/education/whatischemistry/landmarks/tidedetergent.html

http://www.chemistry.co.nz/deterghistorypart2.htm

http://www.newworldencyclopedia.org/entry/Soaps_and_Detergents