JP2013022954A - Method of producing fiberboard having improved water resistance, fire resistance and physical strength - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a fiberboard having superior water resistance and fire resistance, and large physical strength using organic natural fiber.SOLUTION: There is provided the method of producing the fiberboard having improved water resistance, fire resistance and physical strength, in which organic natural fiber 4 such as fiber of wood, cotton, coconut fiber, and bagasse squeezed waste is dipped in a silicate soda solution and then dried, a magnesium chloride solution is sprayed to react in the organic natural fiber 4, and crystal of magnesium silicate 6 which is insoluble in water and incombustible is produced.

Description

  The present invention relates to a fiberboard having improved water resistance, fire resistance and physical strength by using organic natural fibers such as wood fibers, cotton, palm fruit fibers and bagasse squeezed residue.

  Conventionally, in order to improve the water resistance of the organic natural fiber as described above, a synthetic resin resistant to water is often impregnated or applied. Moreover, in order to improve fire resistance, it was a usual method to add a lot of inorganic substances.

Problems to be solved by the invention

(B) Although it was easy to improve water resistance by impregnating organic natural fibers as described above with a synthetic resin that is resistant to water, many synthetic resins are organic and weak against high temperatures. When the temperature is raised, there are disadvantages such as thermal decomposition, generation of smoke and combustion gas, and the gas is also harmful and toxic.
(B) In order to improve the fire resistance, conventionally, inorganic incombustible materials such as cinnabar and mica have been blended, and sodium oxalate has been applied or impregnated. If you add too much or mica, the organic natural fiber itself will burn, and sodium oxalate can be used to make the organic natural fiber incombustible, but sodium in sodium oxalate There are problems that ions are eluted in water and react with carbon dioxide in the air to form sodium carbonate.
The present invention has been made to solve the above problems.

Means to solve the problem

Disperse organic fibers such as wood fiber, cotton, coconut fiber, bagasse squeezed residue in water, and spread on fine mesh or cloth belt such as a wire mesh. After being molded by machining, it is dried to a moisture content of about 10% to obtain an initial dry fiberboard.
This initial dry fiberboard is immersed in a sodium oxalate solution having a molar ratio of 2 to 4 and a concentration of 10 to 50% for about 1 minute, and then sufficiently dried to obtain a secondary dry fiberboard. A magnesium chloride solution having a concentration of 10 to 50% is sprayed on the surface of the secondary dry fiberboard. Sodium oxalate contained in the secondary dried fiberboard and sprayed magnesium chloride react instantly to produce magnesium oxalate, a water-soluble and hard inorganic incombustible material. As a result of such a process, the organic natural fiber becomes a fiberboard with improved water resistance & fire resistance and physical strength.
This is a method for producing a fiberboard with improved water resistance & fire resistance and physical strength.

The invention's effect

  Even if the fiberboard is composed of organic natural fibers, sodium oxalate will penetrate into the fiber and become incombustible if it is treated with sodium oxalate solution. Problems remain such as elution of sodium ions and reaction with carbon dioxide in the air. In the present invention, by a method of spraying a magnesium chloride solution on a secondary dry fiber board and reacting with sodium silicate, the soda content is fixed and converted to a stable compound of magnesium oxalate, which is resistant to water and fire. It becomes a board. Furthermore, sodium oxalate impregnated in organic natural fibers reacted with magnesium chloride to form hard and strong magnesium oxalate crystals, which could significantly improve the physical strength of the fiberboard.

Enlarged view of the initial dry fiberboard at the initial stage of the present invention Further enlarged end view of the secondary dry fiberboard in the second stage of the present invention Enlarged view of the fiberboard at the final stage of the present invention

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below.
Organic fibers (4) such as wood fibers, cotton, palm fruit fibers, bagasse squeezed residue, etc. are dispersed in water, then spread on a fine mesh or cloth belt, and then a mold or After being formed by mechanical processing, it is dried to a moisture content of about 10% to obtain an initial dry fiberboard (1). The initial dried fiberboard (1) was immersed in a sodium oxalate solution (5) having a molar ratio of 2-4 and a concentration of 10-50% for about 1 minute, and then sufficiently dried to obtain a secondary dried fiberboard (2 ) A magnesium chloride solution having a concentration of 10 to 50% is sprayed on the surface of the secondary dry fiber board (2). The sodium oxalate (5) contained in the secondary dry fiber board (2) and the sprayed magnesium chloride cause a chemical reaction in an instant, and are insoluble in water and are incombustible inorganic oxalate (6 ) Is generated. As a result of such a process, a fiberboard (3) with improved water resistance & fire resistance and physical strength was obtained.
The present invention is a manufacturing method as described above, and specific examples will be described below.
(I) After immersing old paper such as newspapers and magazines, disperse the paper fibers in water, scoop it up with a fine mesh wire net, remove the moisture, and dry it to make a 2.5% molar ratio of 20% A fiberboard (3) having rigidity and water resistance was obtained when it was soaked in an acid soda solution (5) for 1 minute and then dried by spraying with a 15% magnesium chloride solution.
(B) After immersing and drying corrugated paper in a sodium oxalate solution having a molar ratio of 3.0 and 15%, sprayed with a 15% magnesium chloride solution becomes a highly rigid corrugated paper. When used, a packaging container that can withstand heavy objects much heavier than ordinary cardboard boxes was obtained.
As can be seen in these examples, the present invention makes it possible to use organic natural fibers that can be widely used for strong building materials and packaging containers that have both water resistance and fire resistance, in a relatively simple manner, with a low cost. The possibilities have been opened.

1. 1. Initial dry fiberboard 2. secondary dry fiberboard 3. Fibreboard with improved water and fire resistance and physical strength 4. Organic natural fiber Sodium oxalate6. Magnesium oxalate

Claims (1)

  After organic natural fibers such as wood fiber, cotton, coconut fiber, and squeezed casks are dispersed in water, they are spread on a fine mesh or cloth belt such as a wire mesh, and if necessary, a mold or Molded by machining, dried to about 10% moisture to obtain an initial dry fiberboard, and this initial dry fiberboard was immersed in a sodium oxalate solution having a molar ratio of 2 to 4 and a concentration of 10 to 50% for about 1 minute. Then, it is sufficiently dried to obtain a secondary dry fiber board, and a magnesium chloride solution having a concentration of 10 to 50% is sprayed on the surface of the secondary dry fiber board to obtain oxalic acid contained in the secondary dry fiber board. Soda and sprayed magnesium chloride reacts instantly to produce water-insoluble and hard inorganic incombustible magnesium oxalate, which is characterized by water and fire resistance and Physical strength Method for producing a fiber plate having above.

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