Isopropyl alcohol(IPA CAS67-63-0), also known as 2-propanol or rubbing alcohol, is a colorless, flammable organic compound with a pungent alcoholic odor. It is widely used as a disinfectant and antiseptic for various purposes, such as cleaning wounds, sterilizing medical equipment, and sanitizing surfaces. But how long does it take for isopropanol to dry after applying it?
Factors affecting drying time
The drying time of isopropyl alcohol depends on several factors, such as the concentration, temperature, humidity, air flow, and amount of alcohol used. Generally, the higher the concentration of alcohol, the faster it evaporates. For example, 70% 2-propanol dries faster than 50% isopropyl alcohol. Similarly, the higher the temperature and air flow, the quicker the alcohol evaporates. On the other hand, the higher the humidity and amount of alcohol used, the slower the alcohol dries.
According to the CDC, isopropanol has a vapor pressure of 33 mm Hg at 20°C (68°F), which means that it readily evaporates at room temperature. However, this also means that it can lose its effectiveness over time if not stored properly in a tightly closed container.
Average drying time
The average drying time of 2-propanol varies depending on the application method and purpose. For example, if you use a cotton swab or a spray bottle to apply a thin layer of 70% 2-propanol to a small area of skin or a metal surface, it may take only a few seconds to dry. However, if you use a cloth or a sponge to apply a large amount of 90% isopropyl alcohol to a large area of fabric or wood, it may take several minutes to dry.
According to Wikipedia, isopropanol has a boiling point of 82.6°C (180.7°F) and a flash point of 11.7°C (53.1°F) in an open cup. This means that it can ignite easily if exposed to an open flame or a spark before it dries completely.
Therefore, it is important to wait until the alcohol has dried completely before using or storing any items that have been treated with it.
Table 1: Estimated drying time of isopropyl alcohol based on concentration and application method
| Concentration | Application method | Drying time |
|---|---|---|
| 70% | Cotton swab | <10 seconds |
| 70% | Spray bottle | <30 seconds |
| 70% | Cloth | <1 minute |
| 90% | Cotton swab | <5 seconds |
| 90% | Spray bottle | <15 seconds |
| 90% | Cloth | <5 minutes |
Note: These are approximate values and may vary depending on other factors such as temperature, humidity, air flow, and amount of alcohol used.
2-propanol manufacturers
Isopropyl Alcohol Suppliers
Extended Reading
Visit Wikipedia of Isopropanol
Isopropyl alcohol is electrically non-conductive when pure!
70% isopropyl alcohol for sanitizing
How to Use 70% Isopropyl Alcohol for Sanitizing