Plywood Glue adhesive : Things you may not know about WBP Glue
In plywood industry, WBP stands for Weather and Boil Proof, the classfication of glue used to make the most durable plywood especially in moisture and water condition. WBP glues are made with melamine or phenolic resin. To be considered exterior grade or marine grade, plywood must be made with WBP glue.
WBP plywood made with regular melamine rather than phenolic resin can maintain lamination in boiling water for between four and eight hours. High quality melamine plywood can withstand boiling water for 10 to 20 hours. WBP plywood using ordinary phenolic resin glue can handle boiling water for one to three days. It should be noted that the length of time plywood can withstand boiling water without delaminating is not only dependent on the glue – it also depends on the production process and raw materials of the plywood used.
WBP is the “A” bond glue line used to bond the veneers. It is a water proof glue line produced from phenolic resins that will not deteriorate under extreme conditions. It is recognised by its black colour.
Commonly referred to as WBP (Water & Boil Proof) or A Bond when used as an adhesive in plywood, phenol formaldehyde provides the structural and moisture durability required in structural, exterior and marine grades of plywood. It is easily identified by the black line between the layers of ply.