Wbp is the abbreviation for "water boiled proof". "water boiled proof" means weather-resistant, boiling-resistant or steam-treated. If plywood coated with wbp glue, it can be used outdoor for a long time (even permanent) with the characteristic of weather resistant waterproof and moisture-proof. Similar to MR glue, WBP glue is not the name of a certain type of glue. WBP is the characteristic of a certain type of glue. If a glue has the characteristics of weather-resistant, water-resistant, this glue can be called wbp glue.
A simple method to detect wbp commercial plywood and wbp film faced plywood is to boil the sample of plywood in water. If the sample does crack after a long time in boiling water, we can say that this plywood has characteristic of weather-resistant and water-resistant properties. And this plywood is wbp plywood (that is, type l plywood).
There are two types of wbp glue, melamine glue and phenolic glue. In general, ordinary melamine plywood can be kept in boiling water for about 4 hours. Good melamine plywood can be kept in boiling water for more than 10 hours or even 20 hours. Ordinary phenolic plywood can be kept in boiling water for about 24 to 72 hours. The best phenolic glue is permanent glue which is very difficult to crack in boiling water.
It should be noted that quality of plywood not only depend on the quality of wbp glue, but also depend on the production process and the quality of core board.
Generally speaking, Wbp glue is used for outdoor plywood such as marine plywood, film faced plywood, structural plywood, billboard plywood etc which need characteristic of weather-resistant and water-resistant. However WBP can also be used for indoor plywood, such as plywood for furniture, plywood for kitchen use, plywood for floor covering, etc which require high quality of weather-resistant and boil-resistant plywood.