How much isopropanol is effective but safe for viny?


I make my own cleaning fluid using isopropanol and distilled water but am aware that some think IPA is not good for vinyl. Since  the contact time is quite limited I think that it is probably OK to use a small amount as a solvent for greasy contaminants. What do you thing know is a safe level? 25  percent, 10 per Cent , or some other level??

rrm
@ invictus005 - what are you trying to clean out of the grooves?  Water is the universal solvent.  
I’m surprised nobody commented alcohol is ten times more expensive than soapy water.
Yeah, it’s a dealbreaker. 91% is a $1 a bottle at Walgreens. If you can’t afford that, you should be in a different hobby, like collecting cans maybe.