Plywood is a multilayer material consisting of at least 3 layers of coniferous or deciduous veneer. Adhesive compounds based on synthetic resins are used to glue the layers together. These substances increase water resistance and mechanical strength of the material.
Is plywood environmentally friendly? Which types can we use for interior decoration, and which are preferable for exterior works? In order to answer these questions, let's consider the main characteristics of the material.
CLASSES OF ECO PLYWOOD
Adhesives with urea-formaldehyde or phenol-formaldehyde resins are used to glue the veneer layers. The ecological compatibility of plywood is determined in accordance with European standards. Materials are divided into three categories:
1. E0 - up to 5 mg per 100 g of product;
2. E1 - up to 10 mg per 100 g of dry plate;
3. E2 - the discharge varies from 10 to 30 mg per 100 g.
Accordingly, the less formaldehyde there is in plywood, the better ecological properties it has.
ECO PLYWOOD TYPES
The products are divided into types depending on the raw materials and the adhesive composition which are used for their production. They are indicated by letter marking. The most common types are:
- Exterior plywood (WBP). It consists of softwood or hardwood veneer, which is treated with phenol-formaldehyde resins, after that it is pressed and cut into specified sizes. The material is characterized by resistance to moisture, high strength and resistance to deformation. Scopes of application are external and internal works.
- Interior plywood (MR). Urea-formaldehyde adhesive is used for bonding and treatment. Interior plywood has higher thickness and water resistance than bakelized plywood. However, it has excellent ecological properties. It is used for interior finishing of non-residential premises.
- Plywood glued with lignin-based natural resins. The high Ecological compatibility of plywood also determines the scope of application - interior decoration of living accommodations.
Buyers often compare ecological compatibility of plywood and chipboard for interior works - flooring, construction of walls, etc. The bottom line is that chipboards are cheaper. However, the same synthetic adhesives are used to glue them. Thus, the difference is only in the price and technical characteristics of the products.
The chemical substances are also used for production of plywood laminates:
- melamine film forms durable waterproof coating on the surface of the material;
- phenolic film based on phenol-formaldehyde resins creates water-repellent, wear-resistant surface.
Review Special plywood