Why Is 70 Isopropyl Better Than 90?

Isopropyl alcohol, also known as rubbing alcohol, is a widely-used disinfectant and antiseptic. It is commonly used to clean and sanitize surfaces, equipment, and tools in various industries, including healthcare, food processing, and electronics. Isopropyl alcohol comes in different concentrations, and the most common ones are 70% and 90%. Many people assume that the higher the concentration, the better the alcohol, but that is not always the case. In fact, 70% isopropyl alcohol is often considered better than 90%. In this article, we will explore the reasons why.

1. Better Antimicrobial Activity

One of the main reasons why 70% isopropyl alcohol is better than 90% is that it has better antimicrobial activity. Antimicrobial activity refers to the ability of a substance to kill or inhibit the growth of microorganisms such as bacteria, viruses, and fungi. According to studies, 70% isopropyl alcohol is more effective at killing these microorganisms than 90%. The reason for this is that the lower concentration allows the alcohol to penetrate the cell walls of the microorganisms more effectively, causing damage to their proteins and nucleic acids, and ultimately killing them. On the other hand, 90% isopropyl alcohol evaporates too quickly to penetrate the cell walls, reducing its antimicrobial activity.

2. Less Flammability

Another advantage of 70% isopropyl alcohol over 90% is that it is less flammable. Flammability refers to the ability of a substance to catch fire and burn. Isopropyl alcohol is a highly flammable substance, and it can easily catch fire if exposed to a spark or flame. However, the flammability of alcohol decreases as its concentration decreases. Therefore, 70% isopropyl alcohol is less flammable than 90%, making it safer to handle and store.

3. Less Irritating to the Skin

Isopropyl alcohol can be irritating to the skin, especially if used frequently or in high concentrations. The higher the concentration, the more irritating it can be. Therefore, 90% isopropyl alcohol can be more irritating to the skin than 70%. In fact, 70% isopropyl alcohol is often used in hand sanitizers and other skin disinfectants because it is less irritating to the skin. It evaporates more slowly than 90%, giving it more time to penetrate the skin and kill the microorganisms, without causing too much dryness or irritation.

4. More Versatile

Finally, 70% isopropyl alcohol is more versatile than 90%. The lower concentration makes it suitable for a wider range of applications, including cleaning electronic devices, removing sticky residues, and disinfecting surfaces. It can also be used as a solvent for oils, waxes, and gums, making it useful in various industries. On the other hand, 90% isopropyl alcohol is too strong for some applications, and it can damage certain materials, such as plastics and rubber.

In conclusion, 70% isopropyl alcohol is better than 90% for several reasons.

It has better antimicrobial activity, is less flammable, less irritating to the skin, and more versatile.
Therefore, when choosing an isopropyl alcohol for your needs, consider the concentration carefully and opt for 70% if possible.
Remember to always handle isopropyl alcohol with care, as it is a flammable and potentially hazardous substance.

Frequently Asked Questions About Why 70 Isopropyl Is Better Than 90

What is isopropyl alcohol?

Isopropyl alcohol, also known as rubbing alcohol, is a common household disinfectant that is used to clean and sanitize surfaces. It is a colorless, flammable liquid that is made from propene, a byproduct of petroleum refining.

Why is 70% isopropyl alcohol better than 90%?

Although 90% isopropyl alcohol has a higher concentration of alcohol, it evaporates too quickly to effectively kill bacteria and viruses on surfaces. 70% isopropyl alcohol has a slower evaporation rate, which allows it to penetrate and kill bacteria and viruses more effectively.

Can 70% isopropyl alcohol be used for disinfecting surfaces?

Yes, 70% isopropyl alcohol is an effective disinfectant that can be used to clean and sanitize surfaces. It is commonly used in hospitals, clinics, and other healthcare settings to disinfect medical equipment and surfaces.

Are there any precautions to take when using 70% isopropyl alcohol?

Yes, it is important to use 70% isopropyl alcohol in a well-ventilated area and avoid inhaling the fumes. It is also flammable, so it should be kept away from open flames and sources of heat. Additionally, it should not be ingested or applied to the skin in large amounts.

You might be interested in: Is Spray Painting As Good As Brush Painting?