Cooperative Extension Service Purdue University Lafayette, Indiana
Mimeo F-42 December, 1962
PARTICLEBOARD INDUSTRY-- FACTS AND REFERENCES
Introduction
This publication presents a general summary of facts and references about the fastest growing segment of the forest products industry in this county--particleboard manufacture. In spite of a great effort for completeness, the bibliography does not encompass all literature on this subject. Undoubtedly, many foreign language documents and articles not included here exist.
Definition
Wood particleboards are relatively dense material (density range of 26 to 50 lbs. per cu. ft.), usually in panel form, made from dry wood particles that have been coated with a binder, formed, and bonded to shape by pressure and heat.
Denser boards, those in the 51 to 75 pounds per cubic foot density range, are classified as hardboards, and those boards (density of 15 to 25 lbs. per cu. ft.) that are not as dense as particleboard are called insulation board.
History
1941 - The first recorded particleboard plant was opened in Bremen, Germany.
1943 - A French patent was granted for a three-layered board developed by Fahrni. This board had coarse particles in the core and thin flat particles on the outer surfaces.
1945 - Particleboard production was
introduced to the United States.
1949 - The Bartrev horizontal continuous compression type process that produced board in a continuous sheet was developed in London, England.
1951 - Boards produced by the Kreibaum vertical extrusion system became available. This system was developed in West Germany.
Production Methods
In general, there are three primary particleboard manufacturing processes:
1.	flat-pressed (also known as the multi-platen process);
2.	the vertical extrusion process;
3.	the horizontal extrusion process. These three production processes differ principally in the method of pressure application during fabrication.
The flat-pressed or multi-platen method is a batch-type of production utilizing press equipment similar in appearance, construction, and operation to a modern heated plywood press. To produce a board utilizing this system, resin coated chips are formed into mats and loaded into a press. The resin is cured under pressure (usually 175psi and upwards) for 5 to 18 minutes at 250 to 400°F. At the completion of the press cycle, the board is removed from the press. Usually the flat-platen presses are large hydraulic presses with 1 to 20 openings. In this country, the platens are commonly heated with hot water. The 4 by 8 foot size of board comprises the