Presspboard is a type of pressed cardboard in which the raw material is paper between 0.1 mm and 50 mm thick. The surface of the pressboard is smooth, easily machined and has dielectric resistance. Another name for pressboard is gasket paper.
Pressboard - properties
Pressboard has high mechanical strength against abrasion and bending. It is also smooth and flexible and has a high dielectric strength. Pressboard is distinguished by its high resistance to electrical breakdown. The material can also withstand short-term thermal loads of up to 350°C. Pressboard can be punched and also partially moulded.
Below are the parameters for 1.6-3.0 mm thicknesses of pressboard, in accordance with EN 60641-3-1:
|Parameter||Pressboard 1.6-3.0 mm|
|Longitudinal tensile strength [MPa]||≥ 105|
|Transverse tensile strength [MPa]||≥ 80|
|Electrical resistance in air [kV/mm]||≥ 11|
|Electrical resistance in oil [kV/mm]||≥ 35|
The use of pressboard
Pressboard is used as an insulating material in electrical engineering. It is used to insulate electrical conductors in motors, oil transformers and other electrical equipment. As a material, it is used for the manufacture of coil skeletons and is also used as interlayer insulation and core insulation. Pressboard is used to make various types of gaskets and is also used in bookbinding (e.g. for covers, office supplies, boxes).
Pressboard - production
Pressboard employs fine fibre raw materials in the form of cotton semi-mass, hard pulp and waste paper. The thinnest pressboard is produced on flat-sheet machines, while the most popular - up to a thickness of 5 mm - is made on corrugated or round-sheet machines. Large thicknesses of pressboard are made by gluing several sheets together. To achieve a smooth effect, the material is treated by pressing and honing in a friction calender and then polished with agate stones. The characteristics and material properties of pressboard are defined in DIN 7733 and IEC 641.
Types of pressboard
Pressboard is a type of paper, available for sale as sheets in brown in various sizes and thicknesses. It is also available in gasket form. As pressboard is made from cellulose, depending on the type of cellulose, it will differ in its specific properties.
Pressboard - where to buy?
Do you want to buy pressboard from a reliable source? Welcome to Voltrog! We sell sheets in thicknesses from 0.1 mm to 50 mm in various sizes. On special request, we prepare gaskets made of pressboard. If you're wondering where to buy pressboard, go to contact of our company - we are a direct distributor of pressboard.
Check also: Mylar film.