Beginner Question: Get 2 Reference Voltages for Comparator using Voltage Regulators
Okay, 0.1V out of 4.5V is +/-2% or so. So a regulator with a 5% tolerance won't be good enough unless you trim it.
Here is one way (Circuitlab is declining to work, so screen cap will have to do)

R1 can be 5%, the others should be at least 1%. The precision resistor values are from the E96 series, so they can be easily purchased.
U1 is drawn as a zener diode, but it actually is a precision trimmed shunt reference IC.
You could replace R1/U1 with a series 5V regulator or reference provided the performance was good enough when you calculate the error budget.