Abstract:
The present invention relates to an inorganic wood-like material, which can be used as a sheet instead of wood, characterized that the said material mainly includes magnesite, magnesium chloride, lime powder, glass fiber, talcum powder and kaolin. The method of preparing the same includes pulverizing, mixing this material in different proportion and molding the mixture to obtain the inorganic wood-like material of the present invention. The material can exhibits a laminated structure comprising wear-resistant surface layer ( 11 ), an inorganic material layer ( 12 ) and a wear-resistant bottom layer ( 13 ). The material can be used for buildings. It is non-toxic, odorless, rustless, non-inflammable and non-oxidable. Its appearance looks like wood and it is easy to be processed. The material is a good environment-protecting material and will be widely accepted by industry and commerce.

Description:
FIELD OF THE INVENTION 
     The present invention relates to building materials, more particularly, to an inorganic wood-like material as a substitute for natural wood. 
     BACKGROUND OF THE INVENTION 
     It has been well realized by more and more people that trees play an important role to the environment of human beings. In order to reduce the consume of natural wood, researchers are working for seeking wood substitutes. It is an object of the present invention to provide an inorganic wood-like material made from cheap minerals and non-toxic recycled materials to change the history of only replying on natural wood material in building industry. 
     SUMMARY OF THE INVENTION 
     The object of the invention is achieved by providing an inorganic wood-like material made of raw minerals, such as magnesite, magnesium chloride, lime powder, plant powder, glass fibre, protective mesh and processed to a sheet as a kind of man-made inorganic wood substitute. 
     The inorganic wood-like material is made of hard raw minerals. Such material is fire-resistant (non-inflammable), water-proof, anti-corrosive, non-rust, durable and non-oxidation, non-deformable and cannot be eaten by mouse and moth. The material can be planned, sawed, can bold nails and screws tightly. The surface of the sheet is easy to be processed. The certificate of fire-resistance up to 4-hours under BS476PARTZO has been issued with respect to the material of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the following drawings: 
         FIG. 1  shows an illustrating view of a first embodiment of the sheet made of the inorganic wood-like material of the present invention; 
         FIG. 2  shows an illustrating view of a second embodiment of the sheet made of the inorganic wood-like material of the present invention; 
         FIG. 3  shows an illustrating view of a third embodiment of the sheet made of the inorganic wood-like material of the present invention; 
         FIG. 4  shows various applications of the sheet made of the inorganic wood-like material of the present invention, including fire-resistant doors, prefabricated houses, garages, heat and sound insulating walls, roof-covers, plates, sandwich plates and floorings, ceilings, movable toilets, rails, enclosing walls for construction sites, and so on. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The features of the inorganic wood-like material of the invention will be described in details with reference to the accompany drawings. 
     With reference to  FIG. 1 ,  FIG. 1  shows an illustrating view of a first embodiment of the sheet made of the inorganic wood-like material of the present invention. The inorganic wood-like material comprises magnesite, magnesium chloride, lime powder, glass fibre, talcum powder and kaolin. Such raw materials are pulverized to become particles or powders and then molded to form a sheet for use. In this embodiment, the laminated structure of the sheet includes three layers from the outer side to the inner side, i.e. a wear-resistant surface layer  11 , an inorganic material layer  12 , and a wear-resistant bottom layer  13 , in which the composition and the ratio of the components of the two-wear-resistant lays are same, which comprise 45%-60% magnesite, 15%-20% magnesium chloride, 5%-10% lime powder, 0.8%-10% glass fibre, 5%-8% talcum powder, and 10%-15% kaolin (by weight percentage). Beside the above-mentioned components in the same ratio, the inorganic material layer  12  sandwiched between the wear-resistant surface layer  11  and the wear-resistant bottom layer  13  further comprises 18%-25% plant powder in order to be capable of holding nails tightly. However, the other two layers cannot contain such plant powder to ensure that they are hard and wear-resistant. 
     With reference to  FIG. 2 ,  FIG. 2  shows an illustrating view of a second embodiment of the sheet made of the inorganic wood-like material of the present invention. In this embodiment, the laminated structure of the sheet includes five layers from the outer side to the inner side, i.e. a wear-resistant layer  21 , an inorganic material layer  22 , a heat and sound insulating layer  23 , an inorganic material layer  24  and a wear-resistant bottom layer  25 . Compared with the first embodiment in  FIG. 1 , the wear-resistant surface layer  21  and the wear-resistant bottom layer  25  are the same as those layers  11  and  13 ; the inorganic material layers  22  and  24  are the same as inorganic material layer  12  of the above-mentioned embodiment. In addition, the sheet of the present embodiment further comprises a heat and sound insulating layer, so that it has an additional function of heat and sound insulation, which is advantageous over the first embodiment. The heat and sound insulating layer comprise similar components as those of inorganic material layer  12 , except that it further comprises 10%-20% glass wool. Such heat and sound insulating sheet is suitable for partition of apartment and cold storage. 
     With reference to  FIG. 3 ,  FIG. 3  shows an illustrating view of a third embodiment of the sheet made of the inorganic wood-like material of the invention. The laminated structure of the sheet comprises six layers from the outer side to the inner side, i.e. a wear-resistant layer  31 , a protective mesh layer  32 , an inorganic material layer  33 , a heat and sound insulating layer  34 , an inorganic material layer  35 , and a wear-resistant layer  36 . As compared with the second embodiment shown in  FIG. 2 , the difference is that the sheet of the third embodiment includes a protective mesh layer  32 . Therefore, it is more difficult to break the sheet of the present embodiment. When being impacted by a hard object, the sheet will not tend to smash to pieces. It is tough. The main components of each layers are similar to those layers of the embodiment in  FIG. 2 , essentially containing magnesite, magnesium chloride, lime powder, glass fibre, talcum powder, kaolin and plant stalk powder, except for the protective mesh layer  32 , which may weight about 0.5%-0.8% of the total weight of the sheet. The protective mash can be a metal net, or a glass fibre net, woven or nonwoven glass fibre cloth. Such laminated sheet is fire-resistant, water-proof, heat and sound insulating, cannot be eaten by mouse and moth, and provide enhanced protection against impact. It can be used repeatedly to form movable houses, garages, camps, enclosing walls for construction site, and so on. In order to become more sturdy, such sheet could be added 0.8%-10% enhanced additive when used as outer walls. 
     With reference to  FIG. 4 ,  FIG. 4  shows examples of the application of the sheet made of the inorganic wood-like material of the present invention. As shown, the sheet of the invention can be used to form fire-resistant doors  41 , doors  42 , indoor and outdoor stairs and rails  43 , movable toilets, houses and prefabricated houses/camps  45 , roof-covers  46 , fire-resistant plates  47 , ceilings  48 , plates, sandwich plates and floorings  49 , pallets for transportation, and so on. 
     Since the material of the present invention has distinctive advantages, it will be widely accepted by industry and commerce. 
     The method of producing the wood-like material sheet or other articles with desired shape is described below. For example, the wood-like material sheet shown in  FIG. 1  can be produced as follows. A magnesium chloride solution, such as a water solution of magnesium chloride, is prepared, which is used as a binder. No additional binder is required during the process of molding a sheet or other article from the wood-like material of the present invention. In this embodiment, magnesium chloride is dissolved in water to obtain a uniform water solution of magnesium chloride with a density of about 22-25 degrees of the Baumé hydrometer scale. For producing the wear-resistant layers  11  and  13 , a dry mixture of components such as magnesite, lime powder, glass fibre, talcum powder, and kaolin is prepared and thoroughly mixed. These components are pulverized or in powder form, the glass fibre is in the form of fine pieces as well known in the art. The percentage of the above components is determined so that the final product comprises 45%-60% magnesite, 15%-20% magnesium chloride, 5%-10% lime powder, 0.8%-10% glass fibre, 5%-8% talcum powder, and 10%-15% kaolin (by weight percentage). If desirable, other additives can be added. Then, the dry mixture is blended with the water solution of magnesium chloride with a density of about 22-25 degrees of the Baumé hydrometer scale to obtain an uniform slurry mixture. In this embodiment, the slurry mixture contains about 30% of the dry mixture and about 70% (by weight) of the water solution of magnesium chloride. If desirable other ratio can be used, for example, 25%-35% of the dry mixture and 65%-75% of the water solution of magnesium chloride are used to form a slurry mixture. The uniform slurry mixture is poured into a mold of desired shape (In this embodiment, a sheet is molded) for molding. The uniform slurry mixture can be cured in the mold at ambient temperature and pressure or to be heated to shorten the cure time. Under ambient temperature and pressure, curing process will take several hours, for example about 8 hours. While under heated condition, it takes much shorter time, for example as short as about 30 minutes, to cure the slurry mixture. 
     For producing the inorganic material layer  12 , similar process is used except that, in addition to magnesite, lime powder, glass fibre, talcum powder, and kaolin, the dry mixture further includes plant powders. The percentage of the above components is determined so that the final product comprises 45%-60% magnesite, 15%-20% magnesium chloride, 5%-10% lime powder, 0.8%-10% glass fibre, 5%-8% talcum powder, 10%-15% kaolin, and 18%-25% (by weight percentage) plant powder. The dry mixture is then mixed with the water solution of magnesium chloride with a density of about 22-25 degrees of the Baumé hydrometer scale in the above described ratio, and cured in a mold. 
     The wear-resistant layers  11 ,  13  and the inorganic material layer  12  produced above are bounded together to form the laminated structure of  FIG. 1 . They can be bounded by glue, or nail, or by other chemical or mechanical means. 
     The heat and sound insulating layer  23  shown in  FIG. 2  is produced in the same manner as the inorganic material layer  12  except that, in addition to magnesite, lime powder, glass fibre, talcum powder, kaolin, and plant powder, the dry mixture further includes glass wool. The percentage of the above components is determined so that the final product comprises 45%-60% magnesite, 15%-20% magnesium chloride, 5%-10% lime powder, 0.8%-10% glass fibre, 5%-8% talcum powder, 10%-15% kaolin, 18%-25% plant powder, and 10%-20% glass wool. The dry mixture is then mixed with the water solution of magnesium chloride with a density of about 22-25 degrees of the Baumé hydrometer scale in the above described ratio, and cured in a mold.