Naphthalene Ball

Updated: 2026-08-11

Overview

Naphthalene balls are a common household and industrial chemical primarily composed of naphthalene. They are widely recognized for their use as moth repellents, protecting fabrics and stored items from insect damage. The distinct pungent odor of naphthalene sublimating at room temperature makes it effective for pest control. Historically, naphthalene balls have been used since the early 20th century. They are manufactured by compressing naphthalene into small, spherical shapes, which slowly release vapors. While effective, their use has declined in some regions due to health and environmental concerns.

Physical and Chemical Properties

Naphthalene balls are white, crystalline solids with a characteristic odor. They sublimate readily at room temperature, transitioning directly from a solid to a gas, which is key to their pest-repellent properties. The molecular structure consists of two fused benzene rings, making it a simple polycyclic aromatic hydrocarbon. Chemically, naphthalene is relatively stable but flammable. It has low solubility in water but dissolves well in organic solvents like ethanol and benzene. The sublimation process is temperature-dependent, accelerating in warmer environments.

Main Applications

The primary use of naphthalene balls is as a moth repellent in closets, storage boxes, and other enclosed spaces. They are also employed in the textile industry to protect wool and other natural fibers from moth larvae. Additionally, naphthalene balls serve as a deodorant in toilets and garbage bins due to their strong odor. In industrial settings, naphthalene is used as a raw material in the production of phthalic anhydride, which is further processed into plastics, dyes, and resins. However, stricter regulations have limited some of these applications due to environmental and health risks.

Safety and Storage

Naphthalene balls pose significant health risks if mishandled. Inhalation or ingestion can lead to symptoms like nausea, vomiting, and, in severe cases, hemolytic anemia. Long-term exposure has been linked to cataracts and liver damage in animal studies. Proper storage is critical to minimize risks. Naphthalene balls should be kept in airtight containers, away from food, children, and pets. They should also be stored in cool, dry places to prevent rapid sublimation and reduce fire hazards due to their flammability.

B2B Procurement Guide

For businesses procuring naphthalene balls, it is essential to verify the product's purity and compliance with local pesticide regulations. Suppliers should provide Material Safety Data Sheets (MSDS) detailing handling and disposal guidelines. Bulk purchasing can reduce costs, but storage capacity and shelf life must be considered. Buyers should also explore alternatives like para-dichlorobenzene-based mothballs or natural repellents if regulatory or environmental concerns are a priority.