Features

• 3M Optically Clear Double-Sided Acrylic Adhesive Tape
• >99% Transmission and <1% Haze Level
• Alternative to UV-Cured Optical Adhesives
• Provides a High Bond Strength to a Variety of Surfaces
• Sold in a Pack of 20 Sheets

3M's Optically Clear Double-Sided Tape provides high cohesive and peel strength to reliably bond many transparent substrates or optical devices and is an alternative to our UV-curing optical adhesive. This tape is ideal for bonding optical films together, such as a lenslet foil to a polarizer foil or glass substrate. Additionally, it can be used with bare Indium Tin Oxide (ITO) surfaces. Two thicknesses are available, 2 mils (0.050 mm) and 3 mils (0.075 mm); the thinner sheet offers slightly better transmission where as the thicker sheet is less likely to tear or break during application.

When properly applied, it can resist splashes from acetone, isopropyl alcohol, and cleaners. Furthermore, immersion in water has no measurable effect on the strength and durability of the tape’s bond. For maximum bond strength, the surfaces of the mating pieces should be thoroughly cleaned and dried.

This optically clear, double-sided tape offers high temperature resistance (see the Specs tab for details) as well as long-term durability without yellowing, delaminating, or degrading. A pressure-sensitive rotary cutter may be used to cut the sheets if necessary. See the Bonding Instructions tab for detailed instructions on how to use this tape.

Recommended Tools and Environmental Conditions for
OCA8146-2 & OCA8146-3

• Class 10K Cleanroom or Better
• Vacuum Table or Glass Table Work Station
• Clean Rubber Roller, Autoclave, and Polyester Tape
• Wipes without Free Floating Fibers, Air Ionizer Gun, and Isopropyl Alcohol

3M's Optically Clear Double-Sided Adhesive Tape (OCA) offers exceptional bonding for smooth, transparent substrates such as glass or plastic. Plastic substrates (e.g., PC and PMMA) absorb moisture and outgas when exposed to high temperature or humidity. This causes bubbles to appear in laminated parts and reduces the optical transparency. To avoid this potential problem, plastics can be baked at 85 °C for 2 - 5 hours in order to drive the moisture out of the substrate. The table to the right gives a summary of the steps in the lamination process detailed below.

Click to Enlarge

Lamination Process

Substrate Preparation

1) If using a plastic substrate, bake it at 85 °C for 2 - 5 hours. Before laminating a substrate first clean all surfaces to be bonded together. Use a soft, dust-free cloth or wipe (such as Thorlabs' CP-100 Premium Optical Cleaning Pads) and isopropyl alcohol to clean the substrate surfaces. Inspect the surfaces to ensure that they are clean, dry, and free of dust and other contaminants.

2) Secure the first substrate to a flat, clean surface with the cleaned side up. Ideally the substrate will be secured with a vacuum table, but in the absence of such, polyester masking tape can be used to secure the substrate.

Lamination

3) Remove the first liner from the OCA film. The OCAs come with three tape handles on each sheet to aid the user in removing the film without touching the OCA (see image to the right).

4) Align the OCA with the substrate and use the rubber roller to adhere the OCA onto the secured substrate. Be sure to squeeze out all the air to avoid air pockets in the lamination.

5) Remove the back side liner and align the second substrate (cleaned surface facing the OCA). Roll down on the second substrate to squeeze all the air from the laminated surfaces.

Autoclave

6) An autoclave is typically used as the final step in the lamination process. It uses heat and pressure to squeeze out any remaining air from the laminated surfaces. For the purpose of lamination, a dry autoclave must be used. See the table above for the autoclave settings. After the autoclave is complete, the lamination process if finished.