Role of Particle Deposition and Adhesion in Detergency

From knowledge of the hydrodynamic force required for particle removal one could calculate the force of adhesion. The force of adhesion could be compared with the attractive force calculated from Hamaker s equation. The results showed that the force of adhesion was about two orders of magnitude lower than the theoretical value calculated from the van der Waals attraction. 

It was concluded from the above results that the latex particles are not perfectly smooth ( hairy surface) and hence not in intimate contact with the surface. 

To formulate a good detergent, one has to understand the various processes involved Wetting, removal of dirt, liquid soiling, prevention of redeposition of dirt. 

Below a brief description of the above processes is given, followed by the main topic of the section, namely particle deposition and adhesion and the role of polymers. 

The best wetting agents are not necessarily the best detergents. For best wetting one needs to lower the dynamic surface tension (which is the value at very short periods of time since the process occurs over very short time scales). This requires molecules with shorter chain alkyl chains (Cg) and surfactants with short relaxation times for the micelles (usually high HLB molecules). 

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