um, if you mean what kind of dye, there are only 3 types of dye and the 3 are, Azo metal, Phthalocyanine and cyanine. every manufacturer doesnt have their own dye, they use one of these 3. i believe some manufacturers use a mix of azo and Phthalocyanine for a more stable and affordable disc.
prodisc probably uses Phthalocyanine, as i believe most DVD manufacturers use this. i believe Taiyo Yuden and MCC media are the only 2 that are known to use azo only in their media.
thats a very good scan, for Prodisc. their media is absolute CRAP these days, though. im guessing those are fairly old, as prodisc was pretty good. if they arent old, consider yourself lucky that you got GOOD prodisc.