The Excess of Cleaning Detergent Left on Clothes after Washing

Table of Contents









Effects on environment

Applications of Experiment

Future Research




        We come in contact with detergents everyday voluntarily or involuntarily. Consequently, residue and deposits of detergents can be found virtually anywhere. In our everyday life, they can be found virtually anywhere including our clothes, bodies, beds, towels and even the food that we consume. This is mainly due to the overuse of detergents under the belief that more detergents results in cleaner and newer clothes. However, despite its prevalent use, the knowledge of the components in detergent, its presence in our daily lives and its effects are widely unknown or ignored. Laundry detergent is a type of detergent that is added when one is washing laundry to help get the laundry cleaner. It is often colloquially called laundry soap or simply detergent or soap and it helps wash the fabric in a manner rather comparable to the way soap helps wash hands, other parts of the body, or other things cleaner than washing with water alone. Laundry detergent has traditionally been a powdered or granular solid, but the use of liquid laundry detergents has gradually increased over the years, and these days use of liquid detergent equals or even exceeds use of solid detergent. There are many different kinds or brands of laundry detergent sold, each with its own instructions on how to use it and what amount to use written on the container it comes in. These days, some brands of laundry detergent claim to be more concentrated and can be added in smaller amounts. The detergent can be added onto the laundry or to the wash water at the start of the wash, or it can be added beforehand or soon after starting the wash into a special compartment in a washing machine made for that purpose, to be flushed into the wash by the wash water. The detergent is soluble in water and makes the water wash the laundry better along with agitation or tumbling. The detergent does its work and is needed during the initial "Wash" cycle to separate the dirt or soil out from the fabric. The purpose of the rinse which follow is to rinse the detergent residue from the laundry as well as to remove the dirt suspended in the wash water by replacing the initial wash water with fresh water.

Surfactants is an ingredient found in almost every detergents which is the key that helps in dirt and oil removal. Surfactants reduce the surface tension of water by adsorbing at the air-water interface. They also reduce the interfacial tension between oil and water by adsorbing at the liquid-liquid interface. Surfactants typically have somewhat long molecules which may or may not have a electric charge. Surfactants with uncharged molecules are non-ionic surfactants. Surfactants with positively charged molecules (or ions) are cationic surfactants. Surfactants with negatively charged molecules (or ions) are anionic surfactants. Surfactants with both positively and negatively charged part in the same molecule are zwitterionic surfactants. Most brands of laundry detergent have anionic or nonionic surfactants or a mixture of the two, although cationic surfactants have been used more in laundry detergents. In granular solid detergents, the surfactant is soaked into the solid ingredients. There is usually a limit on how much liquid surfactant can soak into powder or granular solids before making the solid detergent moist and mushy.

Laundry detergents may also have ingredients to help control the pH of the wash water. For example, solid detergents usually contain sodium carbonate (soda ash) or sodium bicarbonate to maintain pH by neutralizing any acidic materials that may enter the wash water. Some other ingredients which solid detergents may have include sodium silicate or some form of sodium phosphate such as trisodium orthophosphate, monosodium orthophosphate, or a form of tripolyphosphate. Some laundry detergents have enzymes to help in stain removal while other detergents have fabric softeners. Perfume or color ingredients are sometimes added for better smell or to give a detergent some color.

As well, there are two different types of washing machines: the North American and the European. The dominating European machine which is widely used throughout Europe and Asia, performs with a multi-rinse system (1 cleaning cycle with 2 or more rinse cycles). Comparably, the less prevalent North American machine which is comparable to the dominance of the European machine, uses the one clean one rinse system. This experiment will compare the single and multi rinse system with different brands of detergents.

             In this experiment, one will observe the amount of detergent left over in clothes after washing with both the European and North American machines. This is a prevalent problem because as mentioned above, we are in contact with these clothing for all or most of our daily lives. Continous use of excess detergents, even if it is the recommended amount for the brand, can lead to diverse problems both large and small. Minor affects would include itchy and dry skin to major affects which include severe dry skin and even allergies. By discovering the amount of detergent left on clothing after wash, we can reduce the amount to better suit our skin or add more rinse cycles to produce more detergent-free clothing.