Phenolic plywood is somewhat of a misnomer.It should more realistically be called "phenolic faced plywood," phenolic faced plywood, or "phenolic covered plywood." The veneer core plywood isn't made of a phenolic resin but's generally birch plywood. It is "phenolic" because both surface veneers are soaked in phenolic resin before attaching them to the plywood. This creates an extremely stable, smooth, durable, highly water-resistant, and attractive surface.
These face veneers can be wood (normally birch) or thick paper, like the core veneers. In either case, they are limited to the core plays under pressure, creating a permanent bond. The actual material doesn't matter so much as it is merely the carrier for the phenolic rosin. A thick layer of this is unnecessary, as it is a coating. If a thicker layer of the phenolic film were to be thick paper was used, there would be no additional advantage.
Some people refer to the phenolic coating of plywood as "resin-impregnated plywood," although this is inaccurate. The other layers are regular hardwood veneers.
As wither high-grade or marine-grade hardwood plywood, many are made with thin veneer layers. Depending on the manufacturer, a 3/4″ sheet of phenolic plywood will likely have either 13 or 15 layers.
What is Phenolic?
Phenolic was the first synthetic plastic resin, created in 1907, and the material used to create Bakelite. Before other plastics existed, electric light switches and other electronic devices were molded from Bakelite.
It is a thermosetting plastic, meaning that it sets into shape by a chemical reaction that produces heat. This allowed Bakelite to be molded in low-pressure molds. In contrast, most of today's plastics are thermoforming, melting, and forming by heat. This requires expensive injection molding machines and molds that withstand high pressure and temperature.
This difference explains how phenolic can coat an engineered wood product while more used chemicals and modern plastics cannot. Since it is molded to the plywood veneer as a liquid, it can soak into the wood fibers, bonding entirely with them.
To attempt to do that with chemicals or a thermoforming plastic would require an adhesive that could bond to both the plastic and the wood fibers (those are hard to find), unlike phenolic, which acts as its adhesive.
Phenolic plywood is primarily manufactured in Scandinavian countries out of Scandinavian Birch. While it is used more extensively in European countries, it is slowly gaining in popularity in the US, primarily for store and shop fixtures, where the smooth surface is a distinct advantage. It is somewhat more expensive than other types of plywood, roughly the same price as marine grade plywood, which is manufactured to similar specifications.
Since it is a primarily European product, don't be surprised to find it in metric sizes or five-foot square sheets. However, most companies provide it in standard four-foot by eight-foot sheets for use here in the USA. Some companies offer 24″ x 48″ project panels, which are, at least, easier to ship. Another option is custom cut sheets, which are available online.
