This is a play on the word immaterial, which means (Of no importance or relevance; inconsequential or irrelevant. Also, another definition is, having no material body or form.). So let's take the word immaterial and simply add an apostrophe after the "I" and before the first "M". What happens to the word? It forms an almost sculptural meta type word that now appears to be saying: I'MMATERIAL, as if it is saying I'm material, or real. There is an implied irony here as the one of the definitions of Immaterial is having no form, but when we look at the image, I'MMATERIAL appears (pun intended) to be disappearing or vanishing from the space it's held within. Can you see it too?