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Particle board, also known as particleboard, chipboard, and low-density fiberboard, is an engineered wood product manufactured from wood chips and a synthetic resin or other suitable binder, which is pressed and extruded. [1] Particle board is often confused with oriented strand board (OSB, also known as flakeboard, or waferboard), a different type of fiberboard that uses machined wood flakes and offers more strength.
Particle board is cheaper, denser and more uniform than conventional wood and plywood and is substituted for them when cost is more important than strength and appearance. Particleboard can be made more appealing by painting or the use of wood veneers on visible surfaces. Though it is denser than conventional wood, it is the lightest and weakest type of fiberboard, except for insulation board. Medium-density fibreboard and hardboard, also called high-density fiberboard, are stronger and denser than particleboard. Different grades of particleboard have different densities, with higher density connoting greater strength and greater resistance to failure of screw fasteners.
A significant disadvantage of particleboard is its susceptibility to expansion and discoloration from moisture absorption, particularly when it is not covered with paint or another sealer. Therefore, it is rarely used outdoors or in places where there are high levels of moisture, except in bathrooms, kitchens and laundries, where it is commonly used as an underlayment shielded beneath a moisture resistant continuous sheet of vinyl flooring.
In dry environments, veneered particleboard is preferred over veneered plywood because of its stability, lower cost, and convenience.
The history of particleboard is unclear. The nineteenth century saw many attempts to make use of sawmill by-products, including sawdust and wood chips, by manufacturing composite boards; conceptual references to processes of manufacturing wood composites similar to particleboard date from 1887. [2] In 1935, Farley and Loetscher Manufacturing Co. became the first plant to manufacture particleboard. [3] A particleboard industry developed over the course of the 1940s. [4]
In 1932, Luftwaffe pilot and inventor Max Himmelheber patented a process for making particleboard without fully impregnating wood fibers with adhesive, distinguishing it from earlier wood composites. [5] This particleboard could be produced with waste products such as planer shavings, off-cuts or sawdust, hammer-milled into chips and bound together with a phenolic resin. Hammer-milling involves smashing material into smaller and smaller pieces until they can pass through a screen. Most early particleboard manufacturers used similar processes, though often with slightly different resins.
It was found that better strength, appearance and resin economy could be achieved by using more uniform, manufactured chips. Producers began processing solid birch, beech, alder, pine and spruce into consistent chips and flakes; these finer layers were then placed on the outside of the board, with its core composed of coarser, cheaper chips. This type of board is known as three-layer particleboard.
More recently,[ when? ] graded-density particleboard has also evolved. It contains particles that gradually become smaller as they get closer to the surface.
Particleboard or chipboard is manufactured by mixing particles or flakes of wood or jute-stick together with a resin and forming the mixture into a sheet. The raw material is fed into a disc chipper with between four and sixteen radially arranged blades. The chips from disk chippers are more uniform in shape and size than from other types of wood chippers. The particles are then dried, and any oversize or undersized particles are screened out.
Resin is then sprayed as a fine mist onto the particles. Several types of resins are used in the process. Amino-formaldehyde based resins are the best performing based on cost and ease of use. Urea melamine resins offer water resistance with more melamine offering higher resistance. It is typically used in external applications, with the coloured resin darkening the panel. To further enhance the panel properties, resorcinol resins can be mixed with phenolic resins, but that is more often used with marine plywood applications.
Panel production involves other chemicals including wax, dyes, wetting agents and release agents, to aid processing or make the final product resistant to water, fire or insects.
After the particles pass through a mist of resin sufficient to coat all surfaces, they are layered into a continuous carpet. This 'carpet' is then separated into discrete, rectangular 'blankets' which will be compacted in a cold press. A scale weighs the flakes, and they are distributed by rotating rakes. In graded-density particleboard, the flakes are spread by an air jet that throws finer particles further than coarse ones. Two such jets, reversed, allow the particles to build up from fine to coarse and back to fine.
The formed sheets are cold-compressed to reduce thickness and make them easier to transport. Later, they are compressed again, under pressures between 2 and 3 megapascals (290 and 440 psi) and temperatures between 140 and 220 °C (284 and 428 °F) to set and harden the glue. The entire process is controlled to ensure the correct size, density and consistency of the board.
The boards are then cooled, trimmed and sanded. They can then be sold as raw board or surface improved through the addition of a wood veneer or laminate surface.
Particle board has had a huge influence on furniture design. In the early 1950s, particle board kitchens started to come into use in furniture construction but, in many cases, it remained more expensive than solid wood. A particle board kitchen was only available to the very wealthy.[ citation needed ] Once the technology was more developed, particle board became cheaper.
Some large companies base their strategies around providing furniture at a low price. To do this, they use the least expensive materials possible. In almost all cases, this means particle board, medium-density fibreboard (MDF), or the like. However, in order to maintain a reputation for quality at low cost, manufacturers may use higher grades of particle board, e.g., higher density particle board, thicker particle board, or particle board using higher-quality resins. One may note the amount of sag in a shelf of a given width in order to draw the distinction.
In general, the much lower cost of sheet goods (particle board, medium density fiberboard, and other engineered wood products) has helped to displace solid wood from many cabinetry applications.
Safety concerns exist for both manufacturing and use. Fine dust and chemicals are released when particleboard is machined (e.g., sawing or routing). Occupational exposure limits exist in many countries recognizing the hazard of wood dusts. [6] Cutting particle board can release formaldehyde, carbon monoxide, hydrogen cyanide in the case of amino resins, and phenol in the case of phenol formaldehyde resins. [7]
The other safety concern is the slow release of formaldehyde over time. In 1984 concerns about the high indoor levels of formaldehyde in new manufactured homes led the United States Department of Housing and Urban Development to set construction standards. Particleboard (PB), medium-density fibreboard (MDF), oriented strand board (OSB), and laminated flooring have been major sources of formaldehyde emissions. In response to consumer and woodworker pressure on the industry, PB and MDF became available in "no added formaldehyde" (NAF) versions, but were not in common use as of 2015 [update] . Many other building materials such as furniture finish, carpeting and caulking give off formaldehyde, as well as urea-formaldehyde foam insulation, which is banned in Canada for installation in a residential closed cavity wall. [8] Formaldehyde is classified by the WHO as a known human carcinogen. [9]
Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that are glued together with adjacent layers, having their wood grain rotated up to 90° to one another. It is an engineered wood from the family of manufactured boards, which include medium-density fibreboard (MDF), oriented strand board (OSB), and particle board.
Engineered wood, also called mass timber, composite wood, human-made wood, or manufactured board, includes a range of derivative wood products which are manufactured by binding or fixing the strands, particles, fibres, or veneers or boards of wood, together with adhesives, or other methods of fixation to form composite material. The panels vary in size but can range upwards of 64 by 8 feet and in the case of cross-laminated timber (CLT) can be of any thickness from a few inches to 16 inches (410 mm) or more. These products are engineered to precise design specifications, which are tested to meet national or international standards and provide uniformity and predictability in their structural performance. Engineered wood products are used in a variety of applications, from home construction to commercial buildings to industrial products. The products can be used for joists and beams that replace steel in many building projects. The term mass timber describes a group of building materials that can replace concrete assemblies.
Oriented strand board (OSB) is a type of engineered wood similar to particle board, formed by adding adhesives and then compressing layers of wood strands (flakes) in specific orientations. It was invented by Armin Elmendorf in California in 1963. OSB may have a rough and variegated surface with the individual strips of around 2.5 cm × 15 cm, lying unevenly across each other, and is produced in a variety of types and thicknesses.
Medium-density fibre (MDF) is an engineered wood product made by breaking down hardwood or softwood residuals into wood fibre, often in a defibrator, combining it with wax and a resin binder, and forming it into panels by applying high temperature and pressure. MDF is generally denser than plywood. It is made up of separated fibre but can be used as a building material similar in application to plywood. It is stronger and denser than particle board.
In materials science, a thermosetting polymer, often called a thermoset, is a polymer that is obtained by irreversibly hardening ("curing") a soft solid or viscous liquid prepolymer (resin). Curing is induced by heat or suitable radiation and may be promoted by high pressure or mixing with a catalyst. Heat is not necessarily applied externally, and is often generated by the reaction of the resin with a curing agent. Curing results in chemical reactions that create extensive cross-linking between polymer chains to produce an infusible and insoluble polymer network.
Phenol formaldehyde resins (PF) are synthetic polymers obtained by the reaction of phenol or substituted phenol with formaldehyde. Used as the basis for Bakelite, PFs were the first commercial synthetic resins (plastics). They have been widely used for the production of molded products including billiard balls, laboratory countertops, and as coatings and adhesives. They were at one time the primary material used for the production of circuit boards but have been largely replaced with epoxy resins and fiberglass cloth, as with fire-resistant FR-4 circuit board materials.
Norbord Inc. was a Canadian company that manufactured wood-based panels and became the world's largest producer of oriented strand board (OSB). Norbord also manufactured particleboard, medium-density fibreboard (MDF) and related value-added products. Norbord had assets of approximately $1.7 billion and employs approximately 2,600 people at 17 plant locations in the United States, Canada and Europe.
Glued laminated timber, commonly referred to as glulam, is a type of structural engineered wood product constituted by layers of dimensional lumber bonded together with durable, moisture-resistant structural adhesives so that all of the grain runs parallel to the longitudinal axis. In North America, the material providing the laminations is termed laminating stock or lamstock.
Pressed wood, also known as presswood, is any engineered wood building and furniture construction material made from wood veneers, wood shavings and particles, sawdust or wood fibers bonded together with an adhesive under heat and pressure.
Hardboard, also called high-density fiberboard (HDF), is a type of fiberboard, which is an engineered wood product. It is used in furniture and in the construction industry.
Laminated veneer lumber (LVL) is an engineered wood product that uses multiple layers of thin wood assembled with adhesives. It is typically used for headers, beams, rimboard, and edge-forming material. LVL offers several advantages over typical milled lumber: Made in a factory under controlled specifications, it is stronger, straighter, and more uniform. Due to its composite nature, it is much less likely than conventional lumber to warp, twist, bow, or shrink. LVL is a type of structural composite lumber, comparable to glued laminated timber (glulam) but with a higher allowable stress.A high performance more sustainable alternative to lumber, Laminated Veneer Lumber (LVL) beams, headers and columns are used in structural applications to carry heavy loads with minimum weight.
Urea-formaldehyde (UF), also known as urea-methanal, so named for its common synthesis pathway and overall structure, is a nontransparent thermosetting resin or polymer. It is produced from urea and formaldehyde. These resins are used in adhesives, plywood, particle board, medium-density fibreboard (MDF), and molded objects. In agriculture, urea-formaldehyde compounds are one of the most commonly used types of slow-release fertilizer.
Kitchen cabinets are the built-in furniture installed in many kitchens for storage of food, cooking equipment, and often silverware and dishes for table service. Appliances such as refrigerators, dishwashers, and ovens are often integrated into kitchen cabinetry. There are many options for cabinets available at present.
In woodworking, veneer refers to thin slices of wood and sometimes bark that typically are glued onto core panels to produce flat panels such as doors, tops and panels for cabinets, parquet floors and parts of furniture. They are also used in marquetry. Plywood consists of three or more layers of veneer. Normally, each is glued with its grain at right angles to adjacent layers for strength. Veneer beading is a thin layer of decorative edging placed around objects, such as jewelry boxes. Veneer is also used to replace decorative papers in wood veneer HPL.
Fiberboard or fibreboard is a type of engineered wood product that is made out of wood fibers. Types of fiberboard include particle board or low-density fiberboard (LDF), medium-density fiberboard (MDF), and hardboard or high-density fiberboard (HDF).
Hexion Inc. or Hexion is a chemical company based in Columbus, Ohio. It produces thermoset resins and related technologies and specialty products.
Waferboard belongs to the subset of reconstituted wood panel products called flakeboards. It is a structural material made from rectangular wood flakes of controlled length and thickness bonded together with waterproof phenolic resin under extreme heat and pressure. The layers of flakes are not oriented, which makes it easier to manufacture. Waferboard is used as a material to build cheap furniture. This type of furniture is usually laminated.
Columbia Forest Products is the largest manufacturer of hardwood veneer and hardwood plywood in the United States. Founded in 1957, it is headquartered in Greensboro, North Carolina. It specializes in decorative, interior veneers and plywood panels that are used in high-end cabinetry, fine furniture, architectural millwork and commercial fixtures. The company distributes its products primarily through a network of wholesale distributors, mass merchandisers and OEMs. Since 1976, the company has been completely employee-owned and currently has 10 manufacturing facilities throughout the U.S. and Canada. At the end of 2006, Columbia converted all of its standard hardwood plywood production to produce formaldehyde-free panels called PureBond. In 2007 Columbia added PureBond formaldehyde-free particleboard to its product range.
Founded in 1873, the Dieffenbacher Group, located in Eppingen in the administrative district of Heilbronn in Baden-Württemberg, is a family-run enterprise in the field of mechanical engineering, plant systems engineering, and construction. They develop and manufacture press systems and complete production systems for the wood composites, automobile, aerospace and recycling industries.
Molded plywood is the term for two- or three-dimensionally shaped products from multiple veneer layers that are glued together through heat and pressure in a pressing tool. The veneer layers are arranged crosswise at an angle of 90 degrees. Molded wood is used for flat furniture components such as seats, backrests and seat shells. When the veneer layers are arranged in the same direction, it is called laminated wood. It is used for armrests and chair frames. After pressing, the blanks are processed mechanically. A particular feature is the ability to produce different variations of shapes from the blanks. Due to its immense strength and low weight, molded wood is particularly suitable for interior decoration, seating furniture, bed slats, skateboards and vehicle construction.
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| Fuelwood | |
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