Partial success

My Canon printer wanted from yesterday to today no longer correct print (banding, etc.). Since the print head can be quite easily removed with Canon I had this soaked before purchasing this product in Isoprophyl. But that could bring a good result.
I have therefore tried with this product and have worked exactly as directed, but konnt only obtain a minimal improvement. Whether in the middle really "miracle substances" are there? Somehow it looked more like Spüli. Well was an attempt. EVT. extends the slight improvement in some off my printer had to be disposed of, unfortunately, since a recent printhead would simply have been totally uneconomical.