**Physicochemical Properties**  
Sodium dodecyl benzene sulfonate, with the English name *sodium dodecyl benzene sulfonate* and abbreviated as SDBS, is a white or light yellow powdery or flaky solid. It is non-volatile, highly soluble in water, forming a semi-transparent solution upon dissolution. It exhibits stable chemical properties in alkalis, dilute acids, and hard water, and is slightly toxic. It is a commonly used anionic surfactant.  

**Surfactant**  
Sodium dodecyl benzene sulfonate is an anionic surfactant and a highly typical sulfonate, possessing functions such as detergency and emulsification. It can be used as a detergent, among other applications, though its hard water resistance is relatively weak. Its performance improves when used in combination with chelating agents. It has a wide range of applications, with a typical use being in laundry detergents.  

**Detergent Action**  
Alkylbenzene sulfonate is a yellow oily substance that, upon purification, can form hexagonal or oblique square flaky crystals. It is slightly toxic but has been recognized as a safe chemical raw material by international safety organizations. Sodium alkylbenzene sulfonate can be used in fruit and tableware cleaning, with the largest application being in detergents. Due to large-scale automated production, it is inexpensive. The sodium alkylbenzene sulfonate used in detergents comes in two structures: branched (ABS) and linear (LAS). The branched structure has low biodegradability and can cause environmental pollution, whereas the linear structure is easily biodegradable, with a biodegradability rate of over 90%, resulting in minimal environmental impact.  

Sodium dodecyl benzene sulfonate is neutral, sensitive to water hardness, not easily oxidized, highly foaming, and possesses strong detergency. It mixes well with various additives and is cost-effective, with a mature synthesis process and wide application, making it an outstanding anionic surfactant. Sodium dodecyl benzene sulfonate exhibits significant detergency against particulate dirt, protein-based dirt, and oily stains, especially excelling in cleaning particulate dirt from natural fibers. Its detergency increases with rising washing temperatures and is more effective against protein-based dirt than nonionic surfactants, while also producing abundant foam.  

However, sodium dodecyl benzene sulfonate has two drawbacks: first, its hard water resistance is poor, and its detergency can decrease with increasing water hardness. Therefore, detergents primarily using it as the active ingredient must be combined with an appropriate amount of chelating agents. Second, it has strong degreasing power, which can cause some skin irritation during handwashing, and washed clothes may feel less soft. It is advisable to use cationic surfactants as softeners during rinsing.  

In recent years, to achieve better overall washing performance, sodium dodecyl benzene sulfonate has often been combined with nonionic surfactants such as fatty alcohol polyoxyethylene ether (AEO). Its primary use is in formulating various types of liquid, powdery, and granular detergents, scouring agents, and cleaning products.