Trial Purpose:
To identify additional products for the coating removal
Date Run:
09/02/2003Experiment Procedure:
One product that was partially successful in the previous trial was diluted to 20% using DI water in a 600 ml beaker. Four semi-aqueous products were used at full strength in 600 ml beakers. Three acidic aqueous products were also selected for evaluation. Two were used at full strength and the third was used diluted to 3 percent using DI water in a 600 ml beaker. All eight products were heated to 120 F using a Crest 40 kHz ultrasonic tank filled with water and degassed for 5 minutes. One lens was placed in each solution and cleaned for 30 minutes. Observations were made at 5, 10, 15, 20 and 30 minutes. Parts were rinsed in DI water for 15 seconds at room temperature and dried using air blow off also at room temperature.
Trial Results:
Westech was the only product to remove the coating from the front of the lens. Kyzen Ionx FCR, Inland Tech EP 921 and Dynamold Solvents DS 104 all effected the coating on the back. The table below lists the observations made during the cleaning process.
| Cleaner | 5 min | 10 min | 15 min | 20 min | 30 min |
| Multi-Kleen | no sign of cleaning | same | same | same | not tested |
| Ionox FCR | became hazy | some peeling; became cloudy when rinsed | cloudy | some flaking | same |
| EP 921 | became hazy | some peeling; became cloudy | some could be rubbed off when rinsed | air blew off some of the flakes | same |
| SC Supersolve | no sign of cleaning | same | same | same | not tested |
| DS 104 | became hazy | flakey with air blowing off some | cloudy | peeling off | same |
| Westech 4712 | tiny spots on front | same | starting to remove coating | same | majority of coating on front was removed with air blow off |
| Citranox | no sign of cleaning | same | same | same | same |
| Geo Guard 3015 | no sign of cleaning | same | few spots developing | same | no change |
Success Rating:
A follow up test, usually based on company input.Conclusion:
Chem Tech Westech CT-4712 removed nearly all of the coating from the front side of the lens. All eight lenses are being returned to client for inspection at their facility.
