Medium-density fiberboard (MDF) is an engineered wood product formed by breaking down softwood into wood fibres, often in a defibrator, combining it with wax and a resin binder, and forming panels by applying high temperature and pressure. It is made up of separated fibers, (not wood veneers) but can be used as a building material similar in application to plywood. It is much more dense than normal particle board. Currently MDF is substituting particle board and wood fibreboard in world furniture and construction industry.
MDF/HDF is an engineered, machineable product with great structural integrity and high ecological compatibility. It offers some significant advantages over material like PB and wood fiber board, including superior dimensional stability and greater versatility in terms of shaping. MDF could be installed in the premises with 80% of humidity against 60% of humidity for natural wood. MDF/HDF is widely used for the furniture, doors and laminated flooring fabrication.
The key MDF benefit is a perfect correlation between thickness and hardness: the thickness could vary from 4 to 22 mm. The MDF surface is flat, smooth, uniform and dense which greatly simplifies the MDF panels machining.
Wood particle board (particleboard – PB)
Wood particle board, or particleboard (PB), is an engineered wood product manufactured from wood particles, such as wood chips, sawmill shavings, or even saw dust, and a synthetic resin or other suitable binder, which is pressed and extruded. Particleboard is a composite material.
Particleboard is manufactured by mixing wood particles or flakes together with a resin and forming the mix into a sheet. The raw material to be used for the particles is fed into a disc chipper with between four and sixteen radially arranged blades. The particles are first dried, after which any oversized or undersized particles are screened out. Resin, in liquid form, is then sprayed through nozzles onto the particles. Once the resin has been mixed with the particles, the liquid mixture is made into a sheet. The sheets formed are then cold-compressed to reduce their thickness and make them easier to transport. Later, they are compressed again, under pressures between two and three megapascals and temperatures between 140 °C and 220 °C. The boards are then cooled, trimmed and sanded. They can then be sold untreated, covered in a wood veneer or laminated with paper.
There are PB panels of very low (350-450 kg/m³), low (450-650 kg/m³), average (650-750 kg/m³) and high (700-800 kg/m³) density with one, three and five layers. It is not recommended to use PB panels in moister places and premises.
Particleboard is a widely used material for the fabrication of cabinet furniture, interior decorations, roof and partition constructions, etc. PB tightly “holds” nails and screws, could be easily machined (cut, drilled, milled, etc.), glued and painted. One more PB benefit is a low price. That is why particleboard is the most widely used material for the fabrication of economy-class furniture: the majority of office furniture is made of PB.
With some of its physical-mechanical properties PB even surpasses natural wood: particleboard swells less than natural wood, is low- inflammable, does not buckle and has thermal and soundproof properties.
PB disadvantages: the presence of formaldehyde resins extracting a certain quantity of formaldehyde. The particleboard is also heavier and less stronger than natural wood.
There are two types of particleboard: Å1 and Å2. E1 is ecologically clean product with low formaldehyde extraction. Å2 is prohibited to use for the production of furniture for children. The most ecologically clean is particleboard made in Austria and Germany.
Wood fiber board
Wood fiber board is a type of engineered wood product that is made out of wood fibers impregnated with synthetic resins which are hot pressed. The raw materials for wood fiber board are wood chips and hogged chips. To improve wood fiber board performance characteristics, paraffin and colophony (to increase waterproof) as well as synthetic resins (to increase the strength) are into the wood pulp.
The wood fiber board types are as follows:
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extra-hard bards (density - 950 kg/m³);
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hard (850 êã/ì³) and semi-hard (400 kg/m³) boards;
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insulating-finishing boards (250 kg/m³);
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insulating boards (up to 250 kg/m³) .
Wood fiber board is very resistant to the humidity difference. Back sides of the majority cabinets and cupboards as well as drawer bottoms are made of wood fiber board. One more fiber board benefit is low price.
Plus: low price and high durability
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