Plaster material manufacturing method and plaster material

Abstract

To provide a plaster material manufacturing method and a plaster material, enabling a powder of a gypsum board to be easily dissolved in water as well as shortening a drying time after application of the plaster material.SOLUTION: A gypsum board having been through pulverization is fired at 120°C to 190°C into hemihydrate gypsum and soluble anhydrous gypsum, and plaster of paris is pulverized to obtain a gypsum powder. Then, the gypsum powder, a slaked lime, a paste, and a fiber material are blended, and water 9 is added thereto to form a plaster material. Then, by converting to hemihydrate gypsum, etc., the solubility to water 9 is elevated and subjecting it to hydration reaction, heat is generated from an inside of a wall surface, thereby shortening its drying time.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a plaster material to be applied to a wall surface, and to the plaster material. More specifically, the present invention relates to a method for manufacturing a plaster material that contains calcium sulfate, a raw material for gypsum boards, as an ingredient, and to the plaster material. [Background technology]

[0002] Generally, plaster materials are applied to wall surfaces and are manufactured with ingredients such as slaked lime, glue, and fiber materials. By applying such plaster materials to wall surfaces, the slaked lime can provide moisture absorption and fire resistance, and the wall surface can be given an uneven surface to give it a design look, so it is often used in traditional Japanese houses.

[0003] Incidentally, in such plaster materials, in addition to slaked lime and the like, plaster materials have been proposed that contain plaster powder made by crushing waste plasterboard (see Patent Documents 1 and 2). If such waste plasterboard could be utilized, the amount of industrial waste could be reduced and the material costs of plaster materials could be reduced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-296211 [Patent Document 2] JP 2005-314200 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when such gypsum board contains gypsum powder, the following problems arise.

[0006] In other words, when gypsum board is crushed and reused as waste material, gypsum dihydrate, the raw material of gypsum board, is poorly soluble in water, so even if it is powdered and added to water, it becomes difficult to uniformly mix the gypsum dihydrate gypsum powder.

[0007] In addition, when applying plaster to a wall, the plaster is generally applied to a surface that has been primed and then left to dry, but depending on the season and weather, it can take several weeks for the plaster to completely dry. Therefore, in order to shorten the drying time, it is necessary to apply the plaster on a hot day or a day with many dry days, which limits the days on which it can be applied.

[0008] Therefore, the present invention has been made with attention to the above-mentioned problems, and aims to provide a manufacturing method for plaster material that makes gypsum board powder more easily soluble in water and shortens the drying time after the plaster material is applied, and to provide said plaster material. [Means for solving the problem]

[0009] In other words, in order to solve the above-mentioned problems, the present invention provides a method for producing plaster material by carrying out the steps of calcining crushed gypsum board to turn it into calcined gypsum, pulverizing the calcined gypsum to turn it into gypsum powder, mixing the gypsum powder with slaked lime, a glue, and a fibrous material to produce a mixture, and adding water to the mixture to produce the plaster material.

[0010] In this way, waste gypsum boards can be reused to reduce the amount of industrial waste, and by making calcined gypsum into hemihydrate gypsum or soluble anhydrous gypsum, the water solubility can be increased. Furthermore, when such calcined gypsum reacts with water, the hydration reaction can generate heat from inside the wall, shortening the drying time of the plaster material.

[0011] In addition, in such an invention, when the gypsum board is fired, it is heated at 120° C. to 190° C. to convert it into hemihydrate gypsum or soluble anhydrous gypsum.

[0012] In this way, the calcined gypsum can be easily hydrated, and the heat from the hydration reaction can shorten the drying time. Furthermore, when the gypsum hemihydrate returns to gypsum dihydrate, it becomes needle-like crystals, which strengthens the bond between the needle-like crystals and the fibrous material, etc., and prevents cracks from occurring when the slaked lime is dried.

[0013] Furthermore, the fiber material used is made of chopped pineapple fiber or banana fiber.

[0014] In this way, the leaves of the pineapple and banana plants can be reused after the fruits have been consumed, reducing the amount of waste from the farm.

[0015] Alternatively, fibers obtained by shredding collected clothing can be used as the fibrous material.

[0016] In this way, discarded clothing can be reused, and the amount of waste can be reduced.

[0017] The mixture also contains glass powder.

[0018] In this way, it will be possible to reuse discarded empty colored bottles of beer, wine, whiskey, etc., as well as waste glass from automobiles and glass from solar panels.

[0019] The slaked lime and gypsum powder are mixed in a weight ratio of 1:8 to 1:2.

[0020] By mixing it in this ratio, it is possible to achieve the appropriate viscosity, making it possible to use the plaster material to shape the wall surface. Effect of the Invention

[0021] According to the present invention, the plaster material is manufactured by the steps of calcining the crushed gypsum board to make calcined gypsum, pulverizing the calcined gypsum to make gypsum powder, mixing the gypsum powder with slaked lime, a glue agent, and a fibrous material to produce a mixture, and adding water to the mixture to produce the plaster material, so that the amount of industrial waste can be reduced by reusing the waste gypsum board, and the water solubility can be increased by making the calcined gypsum into hemihydrate gypsum, soluble anhydrous gypsum, etc. Furthermore, when the calcined gypsum reacts with water, the hydration reaction can generate heat from the inside of the wall surface, and the drying time of the plaster material can be shortened. [Brief description of the drawings]

[0022] [Figure 1] A conceptual diagram showing a process of mixing raw materials for a plaster material in one embodiment of the present invention. [Diagram 2] A flowchart showing the manufacturing process of the plaster material in the same embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0024] The plaster material 1 in this embodiment contains gypsum board 2 as a waste material as a component, and as shown in Fig. 1, the gypsum board 2 is crushed and then calcined to generate gypsum powder 22 of calcined gypsum 23 such as hemihydrate gypsum or soluble anhydrous gypsum, and this gypsum powder 22 is mixed with slaked lime 5, coloring material 8, adhesive 6, fiber material 7, etc. in water 9. By making the gypsum powder 22 into hemihydrate gypsum or soluble anhydrous gypsum in this way, the solubility of the gypsum powder 22 in water 9 is increased, making it easier to mix uniformly, and when the gypsum powder 22 is applied to the wall surface after adding water 9, the hydration reaction of the calcined gypsum 23 generates heat from the inside of the wall surface, shortening the drying time. Hereinafter, this embodiment will be described in detail.

[0025] First, the gypsum board 2 is made from gypsum dihydrate (calcium sulfate) having two molecules of crystal water, and waste gypsum board 2 is used here. When using such waste material, the paper 24 on the surface is peeled off in advance. The peeled off paper 24 is made reusable as waste paper or the like.

[0026] Incidentally, when peeling off the paper 24 from the plaster board 2 in this manner, if the paper 24 is strongly attached to the plaster, it may be difficult to completely peel off the paper 24, and some of the paper 24 may remain behind.

[0027] When removing the remaining paper 24 from the gypsum board 2, first, the paper is crushed to a certain size using a coarse crusher 3. As the coarse crusher 3, a device in which rollers having protrusions on the surface rotate inwardly to crush the paper, or a beating device that crushes the gypsum board 2 while beating the gypsum board 2, etc., are used. Next, the coarsely crushed gypsum pieces 21 are put into a fine crusher 4 to be made into powdered gypsum powder 22. The particle diameter of the gypsum powder 22 is set to a range of 0.2 μm to 100 μm, preferably 0.2 μm to 10 μm. If the gypsum powder is crushed to such a size, when a wall surface is formed by the plaster material 1, a fine pattern can be formed, and later, when water 9 is added to cause a hydration reaction, the reaction time can be shortened and heat can be generated quickly. Then, the coarsely crushed or finely crushed gypsum powder 22 is passed through a sieve, a centrifuge, etc. to separate and remove foreign matter.

[0028] The gypsum powder 22 from which the foreign matter has been removed in this manner is then placed in a calcination furnace and heated until it becomes hemihydrate gypsum or anhydrous gypsum. When hemihydrate gypsum is produced by this incineration, it is heated within the range of 120°C to 150°C, while when soluble anhydrous gypsum is produced, it is heated within the range of 180°C to 190°C. When heated to 300°C or higher, the dihydrate gypsum becomes insoluble anhydrous gypsum, but since this anhydrous gypsum does not undergo a hydration reaction, if a hydration reaction is to occur, a setting accelerator is added.

[0029] Meanwhile, the other raw material of this plaster material 1, slaked lime 5, is made by adding water 9 to calcium oxide obtained by burning limestone, which is calcium carbonate, and slakes it, and is used in a finely pulverized form, just like the gypsum powder 22 of the gypsum board 2. This slaked lime 5 reacts with carbon dioxide in the air and solidifies itself back into hard limestone, which can cause cracks due to drying. For this reason, fiber materials 7 and the like are used to prevent cracks.

[0030] This fiber material 7 is fiber obtained by cutting straw, pineapple, banana, or the like to a certain length. For example, when using pineapple or banana fiber, the fiber is made from the leaves remaining after the fruit is eaten.

[0031] Moreover, since the plaster material 1 obtained by mixing this slaked lime 5 and gypsum powder 22 becomes white, if coloring is required, a coloring material 8 is mixed in.

[0032] Here, glass powder is used as the coloring material 8. As the glass powder, crushed bottles of wine, whiskey, beer, etc., collected by color are used. The size of the crushed glass pieces is set to about 0.2 μm to 10 μm when the plaster material 1 is to be uniformly colored, while the size is set to about several millimeters to several centimeters when the presence of glass is to be emphasized. When glass is used as the coloring agent, sharp edges are rounded to prevent injury by the edges. To round the edges, the edges are rounded by colliding the glass pieces with a mixer or the like to make the surface rough, or by using a grinder or the like.

[0033] The adhesive 6 has high water retention to prevent water shortage during work and has moderate viscosity to make it paste-like, and seaweed adhesive is used here. Examples of seaweed adhesives include ginkgo grass, horn-shaped seaweed, and funori seaweed, which are mixed in powder form like other materials such as slaked lime 5 and gypsum powder 22.

[0034] Such gypsum powder 22, slaked lime 5, glass, adhesive 6, etc. are mixed in a certain weight ratio, and water 9 is added to this to form a paste for use.

[0035] At this time, the ratio of the slaked lime 5 and the gypsum powder 22 to be mixed is 8:1 to 2:1 by weight, and preferably 5:1 to 3:1. At this time, if the ratio of the slaked lime 5 is increased, the drying time can be extended, and conversely, if the ratio of the gypsum powder 22 is increased, the amount of heat generated when gypsum hemihydrate returns to gypsum dihydrate when water 9 is added, and the drying time can be shortened.

[0036] Next, the process of applying the plaster material 1 thus constructed to a wall surface will be described with reference to the flow chart of FIG.

[0037] First, when producing plaster material 1, the paper 24 is peeled off from the plasterboard 2 that is to be used as waste material, and the plasterboard 2 from which the paper 24 has been peeled off is placed in a coarse crusher 3 and coarsely crushed into pieces of several centimeters to several tens of centimeters in size (step S1).

[0038] Then, the coarsely pulverized gypsum pieces 21 are placed in a fine pulverizer 4 and pulverized until the particle diameter falls within a range of 0.2 μm to 100 μm, preferably 0.2 μm to 10 μm (step S2).

[0039] Then, in order to remove foreign matter from the finely pulverized gypsum powder 22, a sieve or a centrifuge is used to remove foreign matter such as residual paper and glue (step S3).

[0040] Next, the gypsum powder 22 from which the foreign matter has been removed is placed in a calcination furnace and heated within a range of 120°C to 150°C to convert it into hemihydrate gypsum, or, if it is to convert it into soluble anhydrous gypsum, it is heated within a range of 180°C to 190°C (step S4).

[0041] In parallel with this, the prepared slaked lime 5, adhesive 6, glass powder as coloring material 8, and fiber material 7 are placed in a container and mixed uniformly in powder form together with gypsum powder 22 (step S5).

[0042] When mixing this slaked lime 5, gypsum powder 22, adhesive 6, fiber material 7, and coloring material 8, the weight ratio of slaked lime 5 to gypsum powder 22 is 8:1 to 2:1, preferably 5:1 to 3:1.

[0043] Then, after mixing the slaked lime 5, gypsum powder 22, coloring material 8, adhesive 6, and fibrous material in the above ratio, water 9 is added thereto and stirred (step S6).

[0044] Then, the plaster material 1 becomes paste-like, and the calcined gypsum 23 such as hemihydrate gypsum and soluble anhydrite contained therein dissolves in the water 9.

[0045] The plaster material 1 to which water 9 has been added in this manner is applied to the wall surface using a spatula, trowel or the like (step S7).

[0046] At this time, the hemihydrate gypsum generates heat through the hydration reaction, and the heat allows the water to evaporate from the wall surface. The hydration reaction also causes the gypsum to become needle-shaped crystals, which bond strongly to the hydrated lime 5, the fiber material 7, and the glass powder. This prevents the hydrated lime 5 from cracking, and strengthens the bond with the glass, preventing the glass from falling.

[0047] The plaster material 1 is then dried by heat generated from within the wall and by the outside air temperature, and the wall surface is completed.

[0048] Thus, according to the above embodiment, the plaster material 1 is manufactured by the steps of calcining the crushed gypsum board 2 to make the calcined gypsum 23, pulverizing the calcined gypsum 23 to make the gypsum powder 22, mixing the gypsum powder 22 with the slaked lime 5, the adhesive 6, and the fiber material 7 to produce a mixture, and adding water 9 to the mixture to produce the plaster material 1. This makes it possible to reduce the amount of industrial waste by reusing the waste gypsum board 2, and to increase the water solubility by making the calcined gypsum 23 into hemihydrate gypsum or soluble anhydrous gypsum. In addition, when the calcined gypsum 23 reacts with the water 9, the hydration reaction can generate heat from inside the wall surface, and the drying time of the plaster material 1 can be shortened.

[0049] The present invention is not limited to the above-described embodiment, but can be embodied in various forms.

[0050] For example, in the above embodiment, hemihydrate gypsum or soluble anhydrous gypsum is used, but it is also possible to heat it to 300°C or higher to turn it into insoluble calcined gypsum, and at that time, foreign matter such as paper 24 remaining in the gypsum powder 22 is burned off.

[0051] In the above embodiment, crushed glass pieces are used as the coloring material 8, but other materials such as pigments may be used. Alternatively, in the case of a wall made of a single white plaster material, it is not necessary to use such a coloring material 8.

[0052] Furthermore, in the above embodiment, fibers such as floss, pineapple, and banana are used as the fiber material 7, but it is also preferable to use fibers remaining after shredding for spinning, or fibers for clothing and the like that use these fibers. [Explanation of symbols]

[0053] 1. Plaster material 2. Gypsum board 21...Gypsum piece 22...Gypsum powder 23. Plaster of Paris 24...Paper 3... Coarse crusher 4. Fine grinding machine 5. Slaked lime 6. Sizing agent 7. Textile materials 8...Coloring material

Claims

1. A step of calcining the crushed gypsum board to produce calcined gypsum; A step of crushing the calcined gypsum into gypsum powder; Mixing the gypsum powder with slaked lime, a glue, and a fibrous material to produce a mixture; adding water to the mixture to form a stucco material; A method for producing a plaster material comprising the steps of:

2. The step of calcining the gypsum board to form calcined gypsum is 2. The method for producing a plaster material according to claim 1, comprising the step of heating the gypsum board at 120°C to 190°C to convert it into hemihydrate gypsum or soluble anhydrous gypsum.

3. 2. The method for manufacturing a plaster material according to claim 1, wherein the fiber material is made by crushing pineapple fiber or banana fiber.

4. 2. The method for producing a plaster material according to claim 1, wherein the fibrous material is made by shredding collected clothing.

5. 2. The method for manufacturing a plaster material according to claim 1, wherein the mixture contains glass powder.

6. 2. The method for producing a plaster material according to claim 1, wherein the slaked lime and the gypsum powder are mixed in a weight ratio of 1:8 to 1:2, respectively.

7. A gypsum powder obtained by pulverizing the calcined gypsum obtained by heating a gypsum board; Slaked lime powder; A powder of adhesive; A fiber material; A plaster material containing

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