This is by far the most common question asked on this site. It wouldn’t be an exaggeration to say it is asked 35-50 times each week.
First of all, I do not claim to speak for any grading company and Immacuclean wasn’t created with their opinions in mind.
That said, Immacuclean is “subtractive” restoration and not additive. This means that it removes material from a book and does not add material. It is completely volatile and therefore evaporates cleanly away. It does not fluoresce or phosphoresce and is therefore not detectable by UV light.
It will quite often leave streaks of material behind after an initial application. This is microscopic paper fines and other detritus moved around during cleaning. To clear these, wipe with another pad of DI water and it should clean them up. Clean in lines perpendicular to your original wipe lines.
Lastly, at the time of this writing, several thousand books have been cleaned with immacuclean and we have never had a single report of a book coming back from CGC with a purple label. We have personally tracked over 200 books known to have been cleaned with immacuclean and all have returned with a blue label.
The this example of a book cleaned with Immacuclean returning with a blue label.
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