Glue

Adhesion relies on both mechanical interlocking (adhesive penetration into porous wood) and chemical bonding. Effective adhesives penetrate cell walls and form strong van der Waals and hydrogen bonds; the ideal bond strength is so high that failure occurs in the wood substrate rather than at the adhesive layer (“wood‑failure”)

Proper application includes controlling glue viscosity, gelation time, pot life, pH, and solid content, as standardized tests (e.g., viscosity flow cup, rotational viscometer) are used to assure consistency and performance in production adhesive batching

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Also, production pressing parameters—especially press pressure—affect the glue-line thickness (GLT). Research shows optimum strength and board density occur around a press pressure of ~10 kg/cm², which minimizes GLT and maximizes mechanical performance using MUF adhesive.