U-Seal 209 Primerless | High Viscosity One-Component Polyurethane Adhesive for Direct Glass Bonding and Structural Bonding, No Primer Needed

U-Seal 209 Primerless is a high-performance, flexible, one-component polyurethane adhesive designed for direct automotive glass replacement and general assembly. The product offers excellent resistance to UV rays, weathering, and aging. Thanks to its exceptional adhesion properties, the adhesive can be applied without the need for a primer on glass, ceramic coatings, and painted metals.

• One-component polyurethane

• Solvent-free, odorless

• No primer required for glass, ceramic coatings, and painted metals

• Suitable for both cold and warm temperature applications

• Exceptional thixotropy, high coverage, non-sagging

• High modulus – maintains torsional stiffness and improves vehicle NVH (Noise, Vibration, Harshness) values

• Capable of withstanding high dynamic pressure

• UV-resistant, weatherproof, aging-resistant, and excellent color stability

• Suitable for use with integrated antennas

Application

U-Seal 209 Primerless is specially designed for windshield bonding in the automotive glass replacement market, as well as side and rear windows for passenger cars, trucks, tractors, and specialized vehicles. The product is ideal for direct glass bonding on vehicles requiring high slip modulus and non-conductive properties. Additionally, it is used for bonding fiberglass-reinforced plastic components (roofs, side panels, and front panels) on vehicles. This adhesive is suitable for all applications requiring strong elastic-structural bonding between different materials (automotive paint, metal sheets, fiberglass, and reinforced plastics) that must withstand mechanical pressure or high temperatures.

Drive-Away Time (DAT)

• Safe drive-away time: 1 hour

• For vehicles equipped with airbags for both the driver and passengers

U-Seal 209 Primerless complies with Federal Motor Vehicle Safety Standard 212 and meets all long-term durability requirements according to N.P.T. laboratory data.

Technical Data

Instructions for Use

Place the adhesive cartridge into a manual or pneumatic caulking gun (equipped with a telescopic piston). Surfaces to be bonded must be thoroughly cleaned, dry, and free from dust or grease. Pre-treat the windshield and its bonding surface according to NPT’s application guidelines, using a cleaning solution or specific activator from NPT’s product line, and apply the black U-PRIMER 130 primer. It is recommended to perform preliminary adhesion tests on the supporting surface. Specific guidelines for primer use can be provided by sending surface samples to our laboratory.

Do not allow curing in the presence of curing silicone sealants. Avoid contact with alcohol and other solvent-based cleaning agents during curing. When applying the sealant, avoid air entrapment. Since the curing system relies on moisture, ensure sufficient exposure to air. Bonded components may require additional holding or support during curing. Shaping and finishing should be done while the sealant is still tacky.

Cleaning Instructions

Clean used tools with acetone or solvent. When the adhesive is uncured, it can be wiped off with paper or cloth. Once the adhesive has cured, it can only be removed mechanically. Avoid direct skin contact by wearing latex, rubber, or polyethylene gloves. If the adhesive contacts skin, remove immediately and wash with soap and water.

Storage Instructions

U-Seal 209 Primerless can be stored for 12 months in its original (unopened) packaging at temperatures between 10°C and 25°C in a dry, cool place. The storage temperature should not exceed 25°C for extended periods. Keep away from damp areas, direct sunlight, and heat sources.