immaterial vs unsubstantial

immaterial and unsubstantial both are adjectives.

Word	Noun	Adjective	Verb	Adverb
immaterial	No	Yes	No	No
unsubstantial	No	Yes	No	No

immaterial (adjective)	unsubstantial (adjective)
not consisting of matter	lacking material form or substance; unreal
of no importance or relevance especially to a law case
without material form or substance
not pertinent to the matter under consideration
(often followed by `to') lacking importance; not mattering one way or the other