Method for producing fiberboard containing ultramicro amount of residual formaldehyde

Abstract

The invention relates to the technical field of manufacturing of artificial fiberboards, in particular to a method for producing a fiberboard containing an ultramicro amount of residual formaldehyde. The method for producing the fiberboard comprises the technological steps of preparation of adhesive, manufacturing of wood fibers, adhesive application, drying, mat formation and pre-pressing, hot pressing and obtaining of a finished product. According to the method, forest logging residues or wood processing residues or bagasse or other materials are used as raw materials for producing the fiberboard, waste materials are changed into valuable things, and full utilization of wood resources is effectively achieved; the adhesive used for producing the fiberboard is adhesive containing only a micro amount of residual formaldehyde, in this way, environmental friendliness and safety are achieved, and the fiberboard has good water resistance and high bonding strength; the fiberboard produced by using the adhesive hardly contains residual formaldehyde and high in binding powder; the content of substances harmful to human bodies is low, the substances harmful to the human bodies hardly exist, and thus harm to the human bodies is reduced; in addition, the internal structure of the board is uniform, the density is proper, the dimensional stability is high, the quality is stable, and the service life is long.

Description

technical field [0001] The invention relates to the technical field of manufacturing fiberboards for decoration materials and building materials, in particular to a production method for fiberboards with ultrafine formaldehyde residues. Background technique [0002] With the progress of society and the continuous improvement of human awareness of environmental protection, man-made panels are gradually replacing natural wood in areas such as architectural decoration. Density board, also known as fiberboard, is a man-made board made of wood fiber or other plant fiber and applied with urea-formaldehyde resin or other suitable adhesives. According to its density, it can be divided into high-density board, medium-density board and low-density board. MDF is soft, impact-resistant, and easy to reprocess. It is a good material for making furniture abroad. However, because the national standard for high-density boards is several times lower than the international standard, the use q...

AI Technical Summary

Problems solved by technology

However, the traditional fiberboard production process has the following defects: ① Due to the use of traditional adhesives, the formaldehyde emission of the finished board cannot meet the standard requirements, and the product requirements can only be met after ammonia treatment, and the amino acid residue in the finished board causes environmental pollution; Adding additives in the hot grinding section will change the index ratio of the adhesive. At the same time, it is difficult to achieve a stable addition ratio, the stability of the adhesive will change, and the difficulty in controlling the formaldehyde emission of the finished board will increase.

[0004] Most of the fiberboards currently on the market can release formaldehyde to meet the national standard requirements (in 2001, the country promulgated the "Limits for Formaldehyde Release in Wood-based Panels and Their Products for Interior Decoration Materials" GB18580-200l, and the release of free formaldehyde is ≤ 1.5 mg / L, can be directly used indoors, decoration materials with free formaldehyde emission ≤ 5.0mg / L must be decorated before being used indoors), but there are still harmful substances released, decoration used in home, office, activities and other places Materials or supplies, such as floors, furniture, wallpapers, ceilings, wooden doors and windows, paints, etc. Although the release of harmful substances from each product will meet the national standard requirements, several decoration materials are used together in the same space and released together. The harmful substances will greatly exceed the national standard, which will seriously threaten the health of the people

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