Norland Optical Adhesive 138 is a clear liquid adhesive that will cure when exposed long wavelength ultraviolet light. NOA 138 is recommended for bonding for glass to glass. Adhesion is also good to cellulose acetate butyrate. NOA 138 is cured by ultraviolet light between 315 to 395 nm. Full cure requires 6 Joules/cm². The adhesive exhibits oxygen inhibition when used as a coating. To overcome this the adhesive must be cured under an inert atmosphere, such as nitrogen.

Typical Properties of NOA 138
Refractive Index 1.38
Temperature Range -15 C to 90° C
Viscosity @ 25C 45-60 cps
Spectral Transmission NOA 138

Keep NOA 138 in a cool (5-22°C) dark place. If refrigerated, allow the adhesive to come to room temperature before using.

Care should be taken in handling the this material. The material Safety Data Sheet should be read for this product. Prolonged contact with skin should be avoided and affected areas should be washed thoroughly with copious amounts of soap and water. If adhesive gets into eyes, flush with water for 15 minutes and seek medical attention.