A 100% solids sealant based on polyisobutylene polymer formulated to impart reinforcement, resist degradation from ultraviolet light, and provide low moisture permeability.
- Excellent adhesion to glass and metal through a wide temperature range.
- Features an extremely low moisture vapor transmission rate.
- Extremely low argon permeance.
- Non-fogging (100% solids).
- Consistent quality.
- Retains flexibility through a wide temperature range to compensate for thermal movement of the insulating glass unit.
- Resists degradation from ultraviolet light and oxidation.
- Available in both black and gray.
- JS-780 is available in pre-extruded strands for applying to spacer bars and in bulk (slug form) for application by various type extruders.
- Pre-extruded Strands: 1/8”, 3/32”, 1/16” diameter
- Slugs: 7.5”D x 9.5” H (15 lb/7 kg)
- 4.5”D x 7”H (4 lb/2 kg)
- 9.5”D x 10.5”H (27 lb/12kg)
- Drums: Steel 55 gallon
JS-780 is used as the primary seal on insulating glass units while providing the main moisture vapor seal between the glass and metal spacer. JS-780 must be used with a secondary seal designed to provide structural strength.
|Moisture Vapor Transmission Rate
0.13/m²/d, 0.060” fi lm, 100° F, 100% RH
|ASTM F 1249|
|ASTM E 2189
|Low Temperature Flexibility
Passes - 40° F, 1/2” mandrel
|ASTM D 3111|
|Weight per Gallon (Specific Gravity)
Black: 8.75 lb/U.S. gal (1.05 g/cc)
Gray: 9.67 lb/U.S. gal (1.16 g/cc)
|Tensile Adhesion Strength
|Argon Permeance &
3 cc/100 in.²/d, 0.31” fi lm
120 cc mil/100 in.²/d
|ASTM D 1434|