Description

#528 CONTACT LENS PITCH is a formulated pitch, used as an industry standard for blocking of contact lenses, to provide high tensile strength with easy removal.

Application

Depending on application, #528 CONTACT LENS PITCH can be applied in two basic methods:

1. Pre-melt #528 CONTACT LENS PITCH in a controlled heating vessel, and apply or pour molten pitch to blocking plate or lap, and then mount the workpiece.
2. Pre-heat the blocking plate or lap and work piece, and wipe the pitch across the heated tool and mount the workpiece.

#528 CONTACT LENS PITCH can be removed from the parts by using UPI’s UNICLEAR or UNICLEAR II. For best results, please consult with UPI technical staff to recommend optimal processing conditions.

Benefits

• Excellent tensile strength
• Easy removal

Physical Characteristics

• Appearance: Black Solid Stick
• Softening Point (°C): 54 ± 3
• Melting Point (°C): 72 ± 3
• Ball Penetration Test (70F, 500 g weight, 1hr) (in): 0.011 ± 0.005

Availability