Pine oil has mild antiseptic and disinfectant properties and a distinct aroma that characterizes Dettol and other products made with pine oil, according to Science Direct.
Castor oil soap is a product made from castor bean oil. The soap contains a high concentration of ricinoleic acid, the active ingredient in castor oil. The ricinoleic acid is essential for holding the other active ingredients in Dettol in cohesive solution until it is diluted with water for use, per the RSC.
Caramel coloring and water are the other ingredients in Dettol. Caramel gives Dettol its yellowish-brown color and the water acts as a diluent, binding the other ingredients together.
Dettol Antiseptic Ingredients
Dettol works by disruption of the cell wall and stopping the function of enzymes.
However, some pharmacists say, Savlon is an antiseptic brand that contains two antiseptics, cetrimide and chlorhexidine gluconate and is better than dettol. Savlon solution is very mild and doesn't irritate the skin. It is better for children as it is mild.
This paper deals with some chemicals and their effect on viruses: https://pdf.sciencedirectassets.com/272390/1-s2.0-S0195670100X01181...
However, some microbes have developed resistance to these chemicals too.
Bacteria resistent to the main biocides Chloroxylenol (Dettol), Cetrimide and Chlorhexidine (Savlon). The exact mechanism of resistance will vary between each resistant bacteria, but bacterial resistance have been found for all of these common biocides.
Overview of resistances:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC88911/
Examples of reported resistance
Chloroxylenol- and tricloshttp://jcp.bmj.com/content/jclinpath
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1146054/pdf/jclinpath0...
Acquired resistance to chlorhexidine - is it time to establish an ‘...
Adaptation to Biocides Cetrimide and Chlorhexidine in Bacteria from...