Best Practices for Laminating Adhesive Application

Laminating adhesive bonds the single-face web to the bottom liner at the double backer. Proper application is critical for board quality and production efficiency.

Understanding the Laminating Process:

At the double backer, laminating adhesive is applied to the flute tips of the single-face web. The bottom liner is then pressed against the adhesive-coated flutes while passing over hot plates.

Key Application Parameters:

Adhesive Weight:

• Typical range: 3-6 g/m² dry weight

• Lower weights for porous papers

• Higher weights for dense or coated papers

• Monitor consumption per MSF

Film Uniformity:

• Even coverage across full web width

• Consistent glue line width on flute tips

• No dry spots or heavy spots

Viscosity Control:

• Typical range: 30-45 Stein-Hall seconds

• Check every 2 hours minimum

• Adjust for temperature changes

Equipment Setup:

Glue Roll Gap:

• Set precisely for flute type

• Check with feeler gauge regularly

• Adjust for paper thickness changes

Doctor Roll:

• Maintains uniform glue film

• Must be parallel to glue roll

• Inspect for wear and scoring

Glue Pan Level:

• Maintain consistent level

• Too high causes dripping

• Too low causes starvation

Hot Plate Settings:

• Temperature: 150-180°C typical

• Boiler-free lines: Lower temperatures with instant adhesive

• Even temperature across width

Troubleshooting Tips:

Weak Bond:

• Increase adhesive weight

• Check gel temperature

• Verify hot plate temperature

Board Warp:

• Balance moisture between liner and single-face

• Check adhesive viscosity

• Verify even glue application

High Adhesive Consumption:

• Reduce glue roll gap

• Check doctor roll condition

• Verify viscosity is in range