at portulano, i use the available leaf, and that is DAP DAP
mind you , i use dap dap leaf as an abraisive with toothpaste.
the anti-fogging objective is utilised by lowering the surface tension of water in the mask so that water molecules won't clump up (to form dews) lowering the surface tension allows water molucules to be evenly spreadout on the mask surface.
this is achieved IF the MASK glass surface is CLEAN. hence the use of toothpaste (with tartar) removes most dirt residues the dapdap leaf helps "scrub" the dirt residues.
the sap of plants helps lower the surface tension of water. in the stems of plants it helps alot to have low surface tension to utilise the "seepage" of water throughout the plant cells. if you notice okra sap, it is madulas...... slimy.
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