In this section we will now study a first series of applications and end uses: panels manufacturing and primary woodworking.
Primary woodworking encompasses adhesives and binders for the production of various types of boards and panels:
1. softwood plywood ( SWPW ) made of several plies of softwood ( Douglas fir, pine tree or other cheap woods ) bonded together so that the grain of successive plies are perpendicular to each other,
2. particle boards ( PB ) made of small wood particles or chips bound together with a binder, usually UF glue,
3. medium density fiber board ( MDF ): this is a higher quality panel with a better finish because here the wood particles are tiny ground fibers, bound with UF glues but compressed at very high pressure in order to get a dense, strong, very stable and heavy panel, with a smooth surface and an excellent dimensional stability when the humidity varies,
4. Hardboard or fiber board, made with inter felted wood fibers, hard, dense and flat,
5. Hardwood plywood ( HWPW ): this is a composite panel made with hardwood facings but the core or inner plies may be softwood or particle board,
6. Oriented strand board, ( OSB ) made from strands of wood bonded together with a waterproof resin or binder. The strands are of larger sizes than for particle boards and they are oriented in perpendicular layers.