Tim,
Regarding ILFORD ILFOTOL, I worked with some people over at the Steve Hoffman site developing alternative cleaning solutions for the Degritter. My book Section XIV.7 summarizes the testing. Of the cleaning solutions tested, ILFORD ILFOTOL produced the most foam (the Degritter is very sensitive to producing foam); so much that we were never able to get a low enough concentration. So, at this point its not a big surprise that at the higher concentration you are seeing foam.
You may be better off with Tergitol 15-S-9 at 0.015% which would be 3X the critical micelle concentration. (EDIT - note that the 0.2 micron absolute filter you are using will remove bacteria) And quoting my book: Chapter VIII:
"VIII.2.2....Surfactants when they are first added to water collect at the surface lowering the surface tension. There is a concentration when the surface tension will not decrease any further, and this point is known as the “critical micelle concentration” (CMC).
VIII.2.3 When the surfactant concentration is greater than the CMC, the surfactant forms aggregate cylindrical and spherical type structures called “micelles” as illustrated Figure 29. As the micelle forms, the surfactant hydrophilic heads position themselves so they are exposed to the water, while the lipophilic tails are grouped together in the center of the structure protected from the water. Micelles are what provide the detergency of a surfactant.
The book in Chapter XIV provides a number of different chemistries for ultrasonics depending on whether its for pre-clean (XIV.9.4) for final clean (XIV.10); and to others who are reading, the best cleaning is achieved with a final DIW rinse. All surfactants regardless of concentration can leave 'some' residue if not rinsed. Whether you will hear it is something else entirely.
Otherwise, one of problems is that almost every equipment application requires some customizing WRT to chemistry and parameter; essentially you have to 'dial-in' what works best for your particular application.
Feel free to ask questions, I will do my best to answer, but Tim this is your thread. If you feel that I am interfering, my apologies, and I will withdraw.
Take care,
Neil Antin
Regarding ILFORD ILFOTOL, I worked with some people over at the Steve Hoffman site developing alternative cleaning solutions for the Degritter. My book Section XIV.7 summarizes the testing. Of the cleaning solutions tested, ILFORD ILFOTOL produced the most foam (the Degritter is very sensitive to producing foam); so much that we were never able to get a low enough concentration. So, at this point its not a big surprise that at the higher concentration you are seeing foam.
You may be better off with Tergitol 15-S-9 at 0.015% which would be 3X the critical micelle concentration. (EDIT - note that the 0.2 micron absolute filter you are using will remove bacteria) And quoting my book: Chapter VIII:
"VIII.2.2....Surfactants when they are first added to water collect at the surface lowering the surface tension. There is a concentration when the surface tension will not decrease any further, and this point is known as the “critical micelle concentration” (CMC).
VIII.2.3 When the surfactant concentration is greater than the CMC, the surfactant forms aggregate cylindrical and spherical type structures called “micelles” as illustrated Figure 29. As the micelle forms, the surfactant hydrophilic heads position themselves so they are exposed to the water, while the lipophilic tails are grouped together in the center of the structure protected from the water. Micelles are what provide the detergency of a surfactant.
The book in Chapter XIV provides a number of different chemistries for ultrasonics depending on whether its for pre-clean (XIV.9.4) for final clean (XIV.10); and to others who are reading, the best cleaning is achieved with a final DIW rinse. All surfactants regardless of concentration can leave 'some' residue if not rinsed. Whether you will hear it is something else entirely.
Otherwise, one of problems is that almost every equipment application requires some customizing WRT to chemistry and parameter; essentially you have to 'dial-in' what works best for your particular application.
Feel free to ask questions, I will do my best to answer, but Tim this is your thread. If you feel that I am interfering, my apologies, and I will withdraw.
Take care,
Neil Antin