December 8, 2004History ------------
Soap has been around for 5000 years. Both
Egyptians and Babylonians used soap for personal cleaning. Soap then was a mixture of rendered animals fats and ashes.
Although its basic principles remain same, it is now made using a sophisticated chemical and manufacturing process.
Do you know that during middle ages use of soap was considered unnatural? Some historians suggest rejection of soap, and associated lack of hygiene, may have contributed to Black Death that ravaged Europe.
Even intolerance has been linked to soap. Some Europeans rejected soap at this time because it was considered a devilish product. Therefore it has been suggested that cultures who continued using this amazing substance may have been prejudiced against.
Even today people think it is a mystery product that they imagine full of numerous secret ingredients boiled up in a caldron. While not a magical product it is definitely a substance that has helped transform society. It is something we use every day to make our busy lives easier and safer.
Detergent is not soap ----------
Prior to World War II laundry was cleaned with soap or soap flakes. After war detergent became predominant laundry cleaning choice. It was less expensive, more convenient, and worked better with new-fangled washing machines.
Unlike soap, detergent lent itself to high speed processes that allowed it to be mass produced in huge quantities for an ever-expanding market.
With time consumers also demanded variations of detergents that would not have been possible with soap based products. Low suds, high suds, high efficiency, phosphate free, cold water types, fruit scented, non scented, baby specific, liquid form, crystal form, and a multitude of other types are all common today.
How clothes are cleaned ------------
"Put clothes in washing machine ... add detergent ... start machine to let water enter ... and then walk away". That is all most people know about washing their clothes.
People do not realize that detergent is only a minor part of cleaning process. The proper cleaning of clothes involves many complex interactions.
In fact did you know it is water in washing machine that does most of cleaning, not detergent? Primarily, it is water mixing with dirt on clothes that lifts off soiling matter and holds it in suspension. Then as washing machine is draining water finishes job by carrying dirt away with it.
Question: So, if water does work, why do we need detergent?
Answer: Because detergent makes it all happen more efficiently.
Water appears to be one large body of fluid. Actually it's not. In fact it is made up of miniscule balls of water because of a phenomenon called surface tension. The best analogy I can use is that surface tension is like shell around an egg. The natural state of water are these tight little balls. And, because of their surface tension they do not want to mix with other balls of water. So to alleviate this problem we introduce detergent into this environment.
The main job of detergent is to break down this surface tension.
Once surface tension is broken water will mix better with other water molecules. This will allow all water balls to flow into a large homogeneous mass that can then be put to work.
By lowering its surface tension water can be made to penetrate clothing fabric rather than slide off its surface. Therefore, detergent makes water more efficient.
Some people describe it as making ater "slippery". Still others refer to it as making water "wetter". Whatever description result is that water can attack dirt more aggressively. The water gets into clothing fibres, loosens dirt, and then holds it until it can be washed away.
Additionally, detergent helps keep dirt suspended within water. This is necessary to prevent particles of dirt from reattaching to fabric. Without detergent this could happen every time water-dirt mixture came into contact with clothing.
The last thing we need for a good wash is impart some energy into water. That is a fancy way of saying we need to make it move. That is job of agitator inside washing machine.
By making water roll it is tumbling water against clothes. This drives water-detergent mixture into clothes and makes them clean faster. Think of it as same principle used by our ancestors when they wet clothes in river and then banged them against a rock to loosen dirt.
