CS252355B1 - Pressed fibreboard of flat or shaped version - Google Patents

Abstract

The purpose of the solution is to reduce the consumption deficit trees with higher natural content resins while maintaining favorable physical and mechanical properties products while improving aesthetic appearance of products. That purpose of the invention is achieved by being superficial layers are formed in a thickness of 2 to 30% from the ridge of thatch to each side of the product from the fibrous mass of woody species with natural content resins and together with the central layer are pressed in a single pressing procedure.

Description

The invention relates to a fibreboard of a planar or shaped design of a special composition of surface layers having hydrophobic properties.

Currently manufactured planar and shaped fibreboard have the same composition throughout their cross-section. In order to reduce the hydrophilic properties of the lignocellulosic raw materials used, which are transferred to the finished product causing enormous swelling and high water absorption, paraffin, synthetic resins or other hydrophobic substances are added in amounts usually up to 2% by weight of the product and often in larger quantities. In addition to the cost of this measure, the added paraffin leaches to a considerable extent on the surface of the product during compression and causes difficulty in particular in gluing, laminating, varnishing and other surface treatments. In such cases, the surface layers are abraded in an amount of up to 20% of the molding depth, which reduces production capacity and increases production costs, including increasing the energy consumption by the proportion attributable to the abrading of the surface layers. However, even this treatment does not achieve a complete perfect state since the paraffin is distributed throughout the molding material.

The aforementioned drawbacks of the prior art are eliminated by a planar or molded fibreboard of the type consisting of three layers of fibrous mass of trees, the surface layers being of fibrous resinous wood, such as pine, spruce and others. an amount of 2 to 30% of the total thickness of the fibrous carpet with a resin content of 0.5 to 7.0% and a central layer of 40 to 90 fiber thickness. it forms a layer of wood fibers treated with paraffin or other hydrophobic substances.

Advantages of the special composition of movable thatch are that the consumption of deficient tree species with higher content of natural resins, rosins is reduced, while

Claims (2)

Fibreboard of planar or shaped design, characterized in that it consists of three layers of fibrous mass of woody species, the surface layers being formed of fibrous resinous wood such as pine, spruce and others, in an amount of 2 flooding effects on the physical and mechanical properties of the products. This solution allows reduction, respectively. completely eliminating the application of paraffin, which has beneficial effects on surface treatment with substances diluted with various solvents, which also dissolve the paraffin and leach to the surface, making it difficult and prolonging their drying out. The novelty of thatch lies in the newly designed special composition, in which the surface layers are made of wood with a high natural content. resins. Example 1 Fibreboard or molded moldings of 3.2 mm thickness made so that the surface layers, the face and the back side are formed when the fibrous carpet is laid in 1 mm thickness of pine wood fiber without the use of paraffin. The central layer is made of beech wood or various 1.2 mm thick paraffin-treated mixtures which are pressed together in a single pressing process. Example 2 Fibreboard of 8 mm thickness made with a lion and a 2 mm thick backside and spruce fibers without the addition of paraffin. The central layer is made of oak or other hardwood fiber, possibly of mixtures of different types of fiber with a thickness of 4 millimeters, treated with drying oils or other hydrophobic material, which are pressed together in one pressing process. The products according to the invention are characterized by a high aesthetic appearance with higher physical and mechanical properties and can be applied lucratively to other production lines of fibreboard in a dry manner, virtually without the extra investment costs. BACKGROUND OF THE INVENTION up to 30% of the total fibrous carpet depth with a resin content of 0.5 to 7.0% and a central layer of 40 to 90% thickness is formed by a layer of wood fibers treated with paraffin or linseed hydrophobic material.