Environmentally friendly phenolic resin powder, model ZY960/ZY960A, is made from water-soluble phenolic resin through spray drying. It is a high-performance thermosetting adhesive suitable for producing plywood/LVL and other engineered wood products of different strength grades from hard/soft veneer materials.
Recommended activation times at different temperatures:
| temperature | 15°C | 30°C |
| activation time (Hours) | 6 | 4 |
Veneer Preparation:
The veneer surface should be smooth and clean, free of dust and resinous substances. The veneer thickness should be uniform.
A moisture content of 6%-12% is recommended; higher moisture content increases the risk of blistering, delamination, glue seepage, and insufficient glue application.
Glue Application:
Depending on the veneer quality, the amount of glue applied to both sides is 320-400 g/m². Thicker veneers require more glue than thinner veneers.
Assembly:
The time from glue application and assembly to pre-pressing should be as short as possible, ideally within 2 hours.
Faster pre-pressing yields better results, preventing glue drying and subsequent bonding defects.Pre-pressing:
Experience shows that a pressure of 7-12 kg/cm² is optimal, with a pre-pressing time of 30-60 minutes.
In low ambient temperatures, the pre-pressing time can be appropriately extended.
Hot Pressing:
The hot pressing pressure is (10±2) kg/cm² when the tree species density is below 550 kg/m², and (14±2) kg/cm² when the density is above 550 kg/m².
The hot pressing time is the time added to the time it takes for heat to transfer from the press plate to the core layer,
in addition to the basic curing time of the adhesive (3 minutes/130-135°C).
For softwood, taking poplar as an example, the heat transfer time is approximately 1-1.1 min/mm at a hot pressing temperature of (130-135)°C.
For hardwood, taking birch as an example, the heat transfer time is approximately 1.6-1.8 min/mm at a hot pressing temperature of (130-135)°C.
When the veneer moisture content is 10-12%, a pressure holding and degassing time of 3-5 minutes is required.
Precautions:
1: The prepared adhesive must be used within 6 hours.
2: Hot pressing temperature should be above 130°C.
3: Different types of wood and strength grades require different glue mixing ratios
