Does antibacterial soap work chemically?
What the comments are trying to say might go something like this.

The antibiotic triclosan that's used in almost all 'antibacterial' products works pretty quickly - by interfering with several processes in the bacterial and fungal membrane.  It doesn't need much more than contact to work.  

That being said, the longer your exposure to the antibiotic, the more thoroughly it will work.  Triclosan can penetrate the blood stream through the skin.  If you have soap suds scrubbing may or may not get the triclosan into more contact with a greater surface area as it diffuses into the skin, but probably won't affect the substantial effect it has killing surface bacteria and fungi/yeasts. 

Its worth noting that the FDA doesn't recommend the use of antibacterial soap or other antibacterial products.  Soap itself is a powerful agent for killing bacteria and other microorganisms and biocides like triclosan probably encourage the emergence of antibiotic resistant strains which present a medical risk to people.