Trial Purpose:
To evaluate alternative cleaners for removing mold release agent from polycarbonate lenses.
Date Run:
02/02/2005Experiment Procedure:
Seven alternatives chemistries were selected from the laboratory's database of test results based on client supplied information. Water was also used as a control. Six of the products were diluted to 5% using DI water in 600 ml beakers. The seventh product (Solsafe 245) was used at full strength. All products were heated to 130 F in a Crest 40 kHz ultrasonic unit filled with tap water. Each was also degassed for 5 minutes. Each lens was analyzed using contact angle goniometry prior to cleaning. Three measurements were made for each lens. One supplied part was immersed into a cleaning solution and cleaned for 5 minutes, followed by a DI water spray rinse at room temperature for 15 seconds and dried using air blow off at room temperature for 30 seconds. Following drying, the lenses were analyzed again using goniometry.
Two parts cleaned by client with current solvent were also analyzed (after cleaning only).
Trial Results:
The seven cleaning products all lowered the contact angle readings. Water cleaning resulted in an increase in the contact angle, signifying that the lens was dirtier after being subjected to the DI water cleaning. The table lists the initial contact angles, final angles, average values for both as well as the difference in the readings for each lens cleaned.
| Coupon # / Part Description | Initial Reading | Final Reading | Aver Initial Reading | Aver Final Reading | Difference |
| 60-3 | 58 | 55 | |||
| Aquavantage 1400 | 74 | 55 | |||
| 75 | 58 | 69 | 56 | 13 | |
| 60-4 | 50 | 55 | |||
| Shopmaster LpH | 70 | 65 | |||
| 75 | 65 | 65 | 62 | 3 | |
| 60-31 | 52 | 50 | |||
| Daraclean 283 | 70 | 50 | |||
| 55 | 48 | 59 | 49 | 10 | |
| 60-14 | 65 | 50 | |||
| Polyspray Jet 790 xs | 75 | 48 | |||
| 52 | 51 | 64 | 50 | 14 | |
| 3x | 61 | 50 | |||
| Valtron SP 2200 | 80 | 60 | |||
| 80 | 65 | 74 | 58 | 15 | |
| x4 | 62 | 58 | |||
| Beyond 2002 | 68 | 65 | |||
| 60 | 60 | 63 | 61 | 2 | |
| 3-111 | 62 | 55 | |||
| Solsafe 245 | 69 | 70 | |||
| 68 | 55 | 66 | 60 | 6 | |
| iv-4 | 50 | 70 | |||
| Water | 65 | 65 | |||
| 73 | 70 | 63 | 68 | -6 | |
| Benchmark 12 | 65 | 48 | |||
| Water | 80 | 65 | |||
| 78 | 65 | 74 | 59 | 15 | |
| Benchmark F12 1 | 58 | 64 | |||
| Valtron SP 2200 | 75 | 59 | |||
| 70 | 55 | 68 | 59 | 8 | |
| Benchmark F12 2 | 65 | 60 | |||
| Solsafe 245 | 65 | 64 | |||
| 64 | 62 | 65 | 62 | 3 | |
| 7 | 20 | ||||
| Current Solvent | 63 | ||||
| 55 | 46 | ||||
| 8 | 44 | ||||
| Current Solvent | 60 | ||||
| 25 | 43 |
Success Rating:
Results successful using TACT (time, agitation, concentration, and temperature, as well as rinsing and drying) and/or other cleaning chemistries examined.Conclusion:
Four of the seven products lowered the contact angle by more than 10 degrees. The lenses cleaned with the current solvent had lower average contact angle measurements then the alternative products. However, the readings for the current solvent were more inconsistent than the alternative products. The current solvent readings ranged from 20 to 63. After analysis was completed it was noted that some of the lenses had water spots on the back side of lens. These could be eliminated with better rinsing drying. All lenses will be sent back to client for analysis.
