I kind of smell numbers don't articulate, which is why I said you need to be accurate.
If that 100K stays in company account as working capital, and you don't call this transaction a dilution, then it can only be a loan from your personal to this entity. Then because you have a partner, you need to specify the term of this loan.
Intuitively this is a dilution. 10W for 20%, varies your holding at 40W then. And there is no capital gain necessary.