September 2024

Soaps & detergents are cleansing products that may include bar soaps and liquid gels for cleaning the hands, face or body; detergent powders or cakes for laundry cleaning purposes; household cleansers for cleaning household items such as furniture, glass, plastic items, etc; and dish cleaning products for washing kitchen utensils and dishes. Surface active agents are the prime ingredients of soaps and detergents. Other than these surface active agents, all soaps and detergents are made using a variety of ingredients that are added in soap and detergent products to give them specific properties and characteristics.

Ingredients of Soaps and Detergents

Soaps Ingredients Soaps are prepared by the alkaline hydrolysis of fats and oils or the saponification process. This soap manufacturing process also produces a by-product ‘glycerol’ which is useful in foods, as an antifreeze, as a tobacco-moistening agent, and in the manufacturing of nitroglycerine and dynamite. The ingredients of soaps and detergents and their percentage (percent of total by weight) used can be listed as follows

• Surfactants (30-70%)
• Plasticizers and binders (20-50%)
• Lather enhancers (0-5%)
• Fillers and binders (5-30%)
• Water (5-12%)
• Fragrance (0-3.0%)
• Opacifying agents (0-0.3%)
• Dyes and pigments (less than 1%)

Properties & Functions of Soaps Ingredients

All the detergent ingredients impart different properties and functions to soaps and detergents. There are certain other specific ingredients that are added in specialty soaps and detergents depending on the action or characteristics desired in the end product. For example, toilet soaps may contain antimicrobial agents to kill or inhibit bacteria which can cause odor or disease. Some other personal cleaning products may be made using abrasives for removing stubborn greasy dirt.

Glycerin is added as an ingredient of soap as an emollient and texture enhancer in personal cleaning products, especially moisturizing soaps or beauty soaps. Sorbitol is another emollient, which is used along with glycerin to help make glycerin soaps more transparent. For making an opaque toilet soap, titanium dioxide can be added to it.

Bleaches, detergent boosters, fillers and builders are laundry cleaning agents that are added to enhance the effectiveness of laundry detergents and soaps and provide special attributes and functions to these laundry cleaning products. The laundry cleaning agents brighten and whiten fabrics and help remove the stubborn stains. These laundry detergent ingredients also convert the soils into colorless, soluble particles which can be removed by detergents and are carried away in the wash water.

Know more about all types of ingredients of soaps and detergents:

The manufacturing of soaps and detergents is a complex process that involves different activities and processes. The size and complexity of these processes and activities may range from small manufacturing plants that employ a small number of people to those with hundreds and thousands of workers. products may range from all purpose products to that are used for a specific application or requirement.

Selection of Raw Materials for Soap Manufacturing

The first phase in the manufacturing of soaps and detergents is the selection of raw materials. Raw materials are selected on the basis of various factors, including – cost, human and environmental safety, compatibility with other ingredients, and the performance characteristics and appearance of the final product. While the actual production process may vary from company to company and manufacturer to manufacturer, there are some steps, which are common to all types of cleaning products.

Saponification Process for Soap Manufacturing

Saponification processes are chemical soap manufacturing processes that produce soap from fatty acid derivatives. Saponification process for soap manufacturing involves hydrolysis of esters under basic conditions to form an alcohol and the salt of a carboxylic acid (carboxylates). Saponifiable substances are the soaps and detergent ingredients that can be converted into soap.

In Saponification soap manufacturing processe, vegetable oils and animal fats are used for making soaps. Triesters or Triglycerides are the greasy materials derived from these diverse fatty acids. Soap manufacturing is doen in a one-step or a two-step process. In the one-step soap manufacturing process, the triglyceride is treated with a strong base, for example, lye, that accelerates cleavage of the ester bond and releases the fatty acid salt and glycerol. This one step soap manufacturing process is the key industrial method for producing glycerol. Sometimes soaps may be precipitated by salting it out with saturated sodium chloride. For soap manufacturing, triglycerides are highly purified but saponification process includes other base hydrolysis of unpurified triglycerides. For example the conversion of the fat of a corpse into adipocere, sometimes known as “grave wax.” This soap manufacturing process is more common where the amount of fatty tissue is high, the agents of decomposition are absent or are negligibly present, and the burial ground is particularly alkaline.

Soap Manufacturing Processes for Different Soap Types

Manufacturing of soaps and detergents can be broadly categorized into Five main types –

Detergent fillers are the materials, which are added in detergents to alter their physical characteristics and properties. The objective of adding fillers to detergents is to make detergents fluid or to turn the fluidized detergents in powder form. Generally the fillers are bulk components in various detergents with their primary role to modify and alter the physical properties of the material.

We can also define detergent fillers as additives that can be added in detergents (along with bleaches, bleach activators, antistatic agents, fabric softners, optical brighteners and antiredeposition agents) to improve the cleansing performance.

Materials
The different materials that can be used as fillers in detergents, include –

• Sodium sulfate
• Sodium chloride
• Borax
• Alcohols
• Anti-foaming agents

Borax can be used in solid detergents to make the detergent powder free-flowing. Alcohols can be added in liquid detergents to increase the solubility of compounds and to reduce the freezing point of mixture. The addition of anti-foaming agents help in lowering the production of foam thereby making the presence of detergents in wastewater less obvious. Sodium chloride or sodium sulphate can also be used as fillers. Sodium sulfate comes at an economical price and has some cleansing effect, especially when it is mixed with a cleansing agent. Corrosion inhibitors, such as sodium silicate can be added to increase the lifetime of the washing machines. Generally the usual content of fillers in detergents is about 5-45%.

Typically, a detergent is a mixture of various substances and is generally made by compounding the different ingredients, sometimes in the form of a slurry and is then spray-dried to yield free-flowing granules. A detergent contains following ingredients, in varying proportions, usually like –

• A surfactant (detergent) (8-18%)
• A builder (20-45%) e.g. phosphates or zeolites
• A bleach (15-30%) e.g. sodium perborate
• A fluorescer – ‘whiter than white’ (0.1%)
• A filler (5-45%) e.g. sodium sulphate
• The detergent also contains water (4-20%) and may also contain up to 0.75% enzyme

Fillers in Cosmetics
Along with detergents, fillers are also widely used in soap and cosmetic products. In these products, fillers are used as binding agents, which are used to give hardness to the soap cake, free-flowing properties to the powders, and more. Some of the applications include uses in talcum powder, detergents and washing powder.

Applications
Detergent fillers have found uses in various applications, such as –

• Detergents
• Soaps and cosmetics
• Dishwasher components
• Household appliances
• Washing machine parts
• Electrical applications

Both soaps and detergents are cleansing products that we frequently use in our daily lives. We use these products to clean our skin and hands wash our clothes without really paying any attention to how they work or is there any difference between them. Although both the soap and detergents perform same action, i.e. cleansing, there is a significant difference between them. We can differentiate the soaps and detergents on the basis of several factors, like – Ingredients, structure, properties, and more.

Mentioned below are some factors, on the basis of which we can differentiate soaps and detergents –

Soaps and Detergents Ingredients

Although both are surfactants (or surface active agents that means a washing compound, which mixes with grease and water), soaps and detergents are not the same thing. Soap manufacturing process is different from that of detergent making. Soaps are usually manufactured using natural materials while detergents are generally synthetic that were developed during World War II, when there was scarcity of oils that are used to make soaps.

Soaps Ingredients

Usually labeled as beauty, facial, or cleansing bar soaps, true soaps are generally produced with natural products (soap and lye) and require very less energy in the manufacturing process. It is possible to make soaps without having leftover by-products, which tend to go to the landfill, and the soap, which flows down the drain while cleaning is biodegradable. These soaps have a pH of 9.5 to 10 (alkaline) that makes them effective cleansing agents and eliminates the requirement for harmful antibacterial chemicals and preservatives.

However, some manufacturers use beef tallow (fat), in soap making, as this is an unused byproduct of meat processing, which can be obtained very cheaply. While saponified beef tallow can be used to make a satisfactory soap, there are some substances in tallow, which that do not saponify, and may cause acne and skin breakouts.

Superior quality soaps are produced with oils, like – palm, castor, coconut, or olive oils, and retain the natural glycerin, rather removing it and selling it for profit, which bulk manufacturers generally do.

Detergents Ingredients

Detergents are generally made from petroleum products with surfactants, foaming agents and alcohol being their primary constituent. To remove the disagreeable odour of these chemicals, detergents are heavily scented with cheap, synthetic and artificial fragrances. Detergents ingredients also include preservatives and antibacterial agents (to increase their shelf life) that make the detergents frequent causes of allergies and reactions. Soap Structure

StructureAll of the soaps are fatty acid salts, which can be categorized by

• A long hydrocarbon chain, that may be monounsaturated (have a double bond, like sodium oleate), polyunsaturated (more than one double bond) or saturated (no double bonds)
• A carboxylate group at the end

Any surfactant (or surface-active agent), that is not soap is a detergent.

Soap Detergent Difference- Properties in Hard Water

The most important difference between a soap and detergent is their behavior in water. A big drawback of washing with soap is that it forms a scum in hard water, which is not easy to clean and is known to turn laundry into a hue.

Soaps form a scum in hard water, which is not easy to rinse away and is known to turn laundry, a grayish hue. The insoluble film that soap leaves can leave a residue on the laundry same like as would see in a shower stall where hard water is present. On the other hand, detergents react less to minerals in water hence does not leave this residue. In case you are living in an area, where the water is soft, a soap will work satisfactorily, but even then a gradual build-up of calcium and magnesium ions (also called ‘curd’) will be left on the fabric.

Another important difference between soaps and detergents is the sensitivity of soaps to acidic conditions. On putting a soap into an acidic (pH

The protonation of oleate ion to form oleic acid forms an uncharged, insoluble molecule that is not surface-active.

The protonated soap molecule does not have a charged head, and so it becomes insoluble in water. The soap molecules precipitate out thereby producing a cloudy mixture that leads to the formation of a scum. Hence, we can say soaps are not suitable for uses in acidic conditions.

Related Articles