Your confusion is warranted. If the x-axis values are %Transmission @ 600nm (yellow-red part of spectrum) how did the analyst gain a transmission HIGHER than 100% with their cationic polymer? Impossible. Other than that absurdity, it shows their Polyquat-74 flocced nearly out of solution at a 2:1 dilution-deposition ratio with water while at a 4:1 ratio Polyqaut-10 (my personal fave) deposited onto substrate better than theirs and guarHPTC deposited even better at a 6:1 dilution-deposition. My conclusion: try not to spend too much time under the shower head when rinsing that 2-in-1 conditioning shampoo off your hair.
It can also be mentioned that both PQ-74 and Cationic guar deposit higher amounts of polymer than PQ-10 (although, the initial transmitance for Cationic guar was 80, so it was a bit more turbid from the start than the other two).
Both curves (from PQ-10 and Cationic guar are broader) than the one from PQ-74, which might mean that they have a range of flocculation rather than a sharp peak.
Also, in this system, PQ-7 doesn’t seem to form coacervates (which is actually no surprising).
Now, it should be understood that the behavior from those graphics depends on the system tested (I’d expect something different if we increase for instance, the amount of Betaine relative to the amount of SLES, or if the secondary surfactant is substituted by a different one).
@Abdullah The vertical axis as @chemicalmatt mentioned, should be Transmittance. In the horizontal axis, the numbers indicate the parts of water per 1 part of your base shampoo (that’s the dilution factor).