Understanding your laundry detergent

December 8, 2004 History ------------ Soap has been around for 5000 years. Both the Egyptians and Babylonians used soap for personal cleaning. Soap then was a mixture of rendered animals fats and ashes. Although its basic principles remain the same, it is now made using a sophisticated chemical and manufacturing process. Do you know that during the middle ages the use of soap was considered unnatural? Some historians suggest the rejection of soap, and the associated lack of hygiene, may have contributed to the 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 the war detergent became the predominant laundry cleaning choice. It was less expensive, more convenient, and worked better with the new-fangled washing machines. Unlike soap, detergent lent itself to the 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 the clothes in the washing machine ... add the detergent ... start the machine to let the water enter ... and then walk away". That is all most people know about washing their clothes. People do not realize that the detergent is only a minor part of the cleaning process. The proper cleaning of clothes involves many complex interactions. In fact did you know it is the water in the washing machine that does most of the cleaning, not the detergent? Primarily, it is the water mixing with the dirt on the clothes that lifts off the soiling matter and holds it in suspension. Then as the washing machine is draining the water finishes the job by carrying the dirt away with it. Question: So, if the water does the work, why do we need the detergent? Answer: Because the 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 the 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 the surface tension is broken the water will mix better with other water molecules. This will allow all the water balls to flow into a large homogeneous mass that can then be put to work. By lowering its surface tension the water can be made to penetrate the clothing fabric rather than slide off its surface. Therefore, the detergent makes the water more efficient. Some people describe it as making the water "slippery". Still others refer to it as making the water "wetter". Whatever the description the result is that the water can attack the dirt more aggressively. The water gets into the clothing fibres, loosens the dirt, and then holds it until it can be washed away. Additionally, the detergent helps keep the dirt suspended within the water. This is necessary to prevent particles of dirt from reattaching to the fabric. Without the detergent this could happen every time the water-dirt mixture came into contact with the clothing. The last thing we need for a good wash is impart some energy into the water. That is a fancy way of saying we need to make it move. That is the job of the agitator inside the washing machine. By making the water roll it is tumbling the water against the clothes. This drives the water-detergent mixture into the clothes and makes them clean faster. Think of it as the same principle used by our ancestors when they wet the clothes in the river and then banged them against a rock to loosen the dirt. Detergent and hard water --------------- One of the things that affects the cleaning process is water hardness. When detergent is used in hard water it produces soap scum. Yes, the same stuff that makes that ring inside your bathtub. The harder the water, the more soap scum. Water hardness is a measure of its mineral content. So, the more minerals, the more soap scum. The more scum, the less concentrated the detergent. Therefore, if your water is hard you need to compensate by using more detergent per load of laundry. Conversely, the softer the water the less detergent is required to clean the clothes. If you read the detergent box it will usually indicate how much detergent is needed for different water hardness. Unsure of your water hardness? Telephone your municipality or water provider and ask for the water hardness level. It is quoted in grains. That is, 2-4 grains is soft, 4-6 grains is medium, and above 6-8 grains is hard water. If you don't know your water hardness, then experiment. Cut back on your detergent. If the clothes still come out clean, cut back further. Detergent quantity per load ---------------- Do not assume that the amount of detergent suggested on the box is correct for you. The manufacturer is offering general guidelines based upon many variable factors. Load size, dirt content, detergent type, machine type, water hardness, or water temperature all effect the amount required. Some experimentation is required to find how much detergent you should use per load. Also, use a measuring cup to dispense your detergent. The plastic measuring cup that comes in the detergent box is there for a reason. Once the perfect amount of detergent required is determined continue to use this same amount for every load. Simply use a marker to draw a line on the measure so your amount per load will be consistent. Remember, simply dumping out a quantity of detergent from the box is a very bad idea. It is not only wasteful but will contribute to poor and irregular cleaning results. New products -------------- In recent years the front-loading washer has become common. They have attracted much attention because they use substantially less water and electricity. A front loader uses about 40% less water and 50% less electricity. The clothes no longer are suspended in a large tub of water. Instead they roll inside a horizontal tub and only pass through water when at the bottom of the tub. The clothes are constantly being picked up and then dropped into the water. This tumbling action takes the place of the agitator used in a top load machine. Along with the introduction of the front-loader has come a new generation of laundry detergent. It is called high-energy, or high-efficiency detergent. Generally referred to as HE detergent. This type of detergent produces very little suds. A low sudsing detergent is necessary for a front loader washer. If suds were present theywould form a cushion at the bottom of the tub, between the clothes and the water. This would drastically reduce the cleaning action of the water. Also, the front-loader machines generally require less detergent per load of laundry. Some sources indicate this is because less water needs less detergent to obtain the same water to detergent ratio. Other sources suggest it is because the HE detergent is more concentrated, and so less is needed to produce the same cleaning action. Although more expensive the detergent used by front-loaders can last a long time. For this reason it is often suggested it be stored in a warm, dry location. If exposed to moisture from the air it can clump up. If this is then placed into a front-loaders dispenser it may not break down properly resulting in a poor wash. The Future ----------------- What will the future bring to the field of laundry detergent and clothes cleaning? Manufacturers have been hinting at a type of washing machine that requires no detergent. Some think it will take the form of a microwave washer. The dirt is radiated to the point where it is virtually vaporized. Sounds like something out of Star Trek. Others suggest washers may use electrically charged particles to do the cleaning. The dirt would be given an electrical charge different from the clothing. In this way the dirt can then be drawn away from the fabric and then disposed of into a filter. At this point in time these things seem rather far-fetched and theoretical. Of course the same is always said until someone learns how to turn a crazy theory into a practical device. For more information about detergent check out http:// www.armandhammer.com http:// www.tide.com