Phenolic Resins

Phenol Formaldehyde Liquid Resin AL 421

Phenol Formaldehyde Liquid Resin AL 421 is a thermosetting liquid resin, which meets all the requirements for a WBP (Water Boil Proof) type adhesive. The powdered hardener filler is added to the liquid prior to use.
The adhesive produces a water-resistant bond and used in hot bonding only.


  • Glue for manufacture of WBP plywood
  • Glue for block board
  • Glue for other wooden products for exterior use with high humidity and moisture


AppearanceReddish-brown liquid
Viscosity at 30˚C, cps50 - 100
Solid Content at 3h/105˚C, %43 - 46
Specific gravity at 30˚C1.200 - 1.240
pH at 30˚C12.0 - 14.5
Gel Time at boiling water (Reactivity)45 - 65 minutes


Store in a cool and dry place. At 20ᴼC it may be stored for about 3 months and for shorter duration at higher temperatures depending on the initial viscosity. The limiting factor is the viscosity which will increase as a function of time. The rate of viscosity increase is dependent on temperature, and consequently the storage time will be related to the temperature at which the resin is stored.

If the storing conditions are extremely unfavorable the resin may gelatinize in the drums and will thus be unfit for use.


AL 421 is available in HDPE drums at a weight of 240kg each.