JP2016142067A - Building board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a building board that hardly causes the breakage of a skin layer even when a strong force is imposed thereon from a fixture for fixing the inorganic building board having a core layer and the skin layer.SOLUTION: A building board 1 comprises a core layer 2 which is formed from a molding material including a hydraulic inorganic material, and a skin layer 3 which is formed from a molding material including a hydraulic inorganic material and which coats the core layer 2. Absolute dry specific gravity of the skin layer is greater than that of the core layer. The skin layer comprises an outermost part on one surface that is directed in a thickness direction of the core layer. The outermost part has strength high enough to prevent breakage even when a force of 135 N per 20 mmis applied thereto.SELECTED DRAWING: Figure 1

Description

  The present invention generally relates to a building board, and more particularly to a building board formed of a molding material mainly composed of a hydraulic inorganic material and having a core layer and a skin layer covering the core layer.

  2. Description of the Related Art Conventionally, inorganic building boards made of materials such as cement and gypsum have been used for various building materials such as outer walls of buildings. Such building boards are formed in various structures from various materials. For example, in Patent Document 1, a base material layer mainly composed of a cement-based inorganic material and a silicic acid-containing substance, and a base material layer mainly composed of a cement-based inorganic material and a silicic acid-containing substance are formed. An inorganic plate consisting of a surface layer is described. Furthermore, when a building board as described in Patent Document 1 is installed in a building, for example, a fixing tool such as a nail, a screw, or a bolt is driven from the building board to the trunk of the building.

JP 2004-123399 A

  When negative pressure is applied to a building board installed in a building by strong wind or the like, as described in Patent Document 1, when the building board includes a plurality of layers, the outermost layer of the building board is strong from the fixture. There was a case that it was damaged by applying force. Also, the outermost layer of the building board may be damaged when a fixture such as a nail, a screw, or a bolt is driven into the building board.

  The present invention has been made in view of the above points, and even if a strong force is applied to an inorganic building board having a core layer and a skin layer from a fixture for fixing the building board, the skin layer is damaged. The purpose is to provide a difficult building board.

The building board according to the present invention includes a core layer formed from a molding material containing a hydraulic inorganic material,
A skin layer that covers the core layer is formed from a molding material containing a hydraulic inorganic material,
The absolute dry specific gravity of the skin layer is larger than the absolute dry specific gravity of the core layer,
The skin layer includes an outermost portion on one surface facing the thickness direction of the core layer,
The outermost portion has a strength that does not break even when a force of 135 N per 20 mm ² is applied.

  In the present invention, even if a strong force is applied from a fixture for fixing an inorganic building board having a core layer and a skin layer, the building board can be provided in which the skin layer is not easily damaged.

It is sectional drawing which shows an example of the building board which concerns on this invention. FIG. 2A is a cross-sectional view showing an example of a state in which a building board is installed in a building. FIG. 2B is a cross-sectional view showing an example of a state in which the outermost building board installed in the building is damaged. It is sectional drawing which shows the modification of the building board which concerns on this invention. It is an outline top view of the metal mold | die with which the extrusion machine used for manufacture of the building board which concerns on this invention, and the extrusion molding machine was equipped. FIG. 6 is a schematic cross-sectional view of a mold provided in the extruder shown in FIG. 5. FIG. 6A is a schematic plan view of a hollow molded body used in the present invention. FIG. 6B is a schematic side view of the hollow molded body shown in FIG. 6A.

  Hereinafter, modes for carrying out the present invention will be described.

  First, the structure of the building board 1 which concerns on this embodiment is demonstrated.

  Although the shape of the building board 1 is not specifically limited, For example, it is a planar view rectangular shape. The building board 1 may be provided with a fitting portion for fitting with another building board 1 as necessary.

  As shown in FIG. 1, the building board 1 includes a core layer 2 formed from a molding material containing a hydraulic inorganic material, and a skin layer 3 formed from a molding material containing a hydraulic inorganic material covering the core layer 2. Is provided.

  The core layer 2 includes a surface facing the thickness direction (hereinafter referred to as a first surface 21) and a second surface 22 facing the opposite direction to the first surface 21. The skin layer 3 covers the entire core layer 2. A portion on the first surface 21 in the skin layer 3 is referred to as an outermost portion 31.

  In this embodiment, when the absolute dry specific gravity of the core layer 2 and the absolute dry specific gravity of the skin layer 3 are compared, the absolute dry specific gravity of the skin layer 3 is larger than the absolute dry specific gravity of the core layer 2. As a result, the core layer 2 can be reduced in weight so that the entire building board 1 can be reduced in weight, and the skin layer 3 can be made denser than the core layer 2 and the strength of the skin layer 3 can be made higher than that of the core layer 2. Can do. The absolute dry specific gravity of the skin layer 3 is preferably 0.8 or more. Although the upper limit of the absolute dry specific gravity of the skin layer 3 is not specifically limited, For example, it is 2.0. The absolute dry specific gravity of the core layer 2 is not specifically limited, For example, it exists in the range of 0.7-1.9.

The outermost portion 31 of the skin layer 3 has a strength that does not break even when a force of 135 N per 20 mm ² is applied. Thereby, the strength of the outermost part 31 of the skin layer 3 can be sufficiently ensured.

  When the building board 1 is installed in a building, for example, as shown in FIG. 2A, a fixing tool 6 such as a nail, a screw, or a bolt penetrates the building board 1 and is driven into the trunk edge 5 of the building. When a negative pressure is applied to the building board 1 installed in the building by a strong wind or the like, a strong force is applied to the outermost part 31 of the skin layer 3 from the fixture 6. When a strong force is applied to the outermost part 31 from the fixing tool 6 in this way, as shown in FIG. 2B, damage may occur such that the periphery of the outermost part 31 where the fixing tool 6 is driven is depressed. In addition, when a strong force is applied from the fixture 6 to the outermost portion 31 of the skin layer 3 when the fixture 6 is driven into the building board 1, the outermost portion 31 may be damaged as shown in FIG. 2B. is there.

However, since the building board 1 of the present embodiment has a strength that does not break even when the outermost portion 31 of the skin layer 3 is applied with a force of 135 N per 20 mm ² , the strength of the outermost portion 31 of the skin layer 3 is sufficiently secured. ing. For this reason, even if a negative pressure is applied to the building board 1 by a strong wind or the like and a strong force is applied from the fixture 6 to the outermost part 31, the outermost part 31 is not easily damaged as shown in FIG. 2B. Furthermore, even when a strong force is applied from the fixture 6 to the outermost portion 31 when the fixture 6 is driven into the building board 1, the outermost portion 31 is hardly damaged as shown in FIG. 2B. In particular, when the absolute dry specific gravity of the skin layer 3 is 0.8 or more and the thickness of the outermost part 31 is 1.5 mm or more, the outermost part 31 is particularly difficult to break.

  Next, the building board 1 will be described in more detail.

  As described above, the core layer 2 of the building board 1 is formed from a molding material containing a hydraulic inorganic material. In this specification, the molding material used for forming the core layer 2 is referred to as a core material. The core material can contain, for example, an inorganic main material, an inorganic admixture, an organic admixture, a reinforcing fiber, and water.

  The inorganic main material is made of a compound containing at least one of silicon and calcium. The inorganic main material is mainly composed of cement, which is a hydraulic inorganic material. The inorganic main material can further contain one or more materials selected from the group consisting of fly ash, silica fume, and silica powder.

  Examples of the inorganic admixture include mica and sodium silicate.

  Examples of the organic admixture include methyl cellulose and organic foam particles. The organic foamed particles can contain, for example, one or more materials selected from the group consisting of styrene resins, vinylidene chloride resins, and acrylonitrile resins.

  The reinforcing fiber includes, for example, pulp and polypropylene fiber.

  In addition to the above raw materials, the core material may further contain an inorganic foam. The inorganic foam can contain, for example, one or more materials selected from the group consisting of pearlite, fly ash balloon, and vermiculite.

  The ratio of each substance contained in the core material is not particularly limited. For example, the core material contains 73 to 97% by weight of an inorganic main material, 1 to 20% by weight of an inorganic admixture, It is preferable that the admixture is contained in the range of 1 to 3.5% by weight and the reinforcing fiber is contained in the range of 1 to 3.5% by weight.

  As described above, the skin layer 3 of the building board 1 is formed from a molding material containing a hydraulic inorganic material. In this specification, the molding material used for forming the skin layer 3 is referred to as a skin material. This skin material can contain, for example, an inorganic main material, an inorganic admixture, an organic admixture, reinforcing fibers, and water. The skin material may further contain an additive.

  The inorganic main material, the inorganic admixture, the organic admixture, and the reinforcing fiber included in the skin material are, for example, the inorganic main material, the inorganic admixture, the organic admixture, and the reinforcing fiber included in the core material. Is the same.

  The ratio of each substance contained in the skin material is not particularly limited. For example, the skin material contains 69.5 to 97.5% by weight of the inorganic main material and 1 to 20% by weight of the inorganic admixture. Of these, the organic admixture is preferably contained in the range of 1 to 3.5% by weight, and the reinforcing fibers are preferably contained in the range of 1 to 7% by weight.

  An uncured molded body (green sheet) is produced by molding the core material and the skin material. The uncured molded body is cured, cured, and further dried, whereby the building board 1 including the core layer 2 and the skin layer 3 is obtained.

  In the step of curing the uncured molded body, for example, one or more types of curing selected from the group consisting of room temperature curing, steam curing, and autoclave curing are performed. In this embodiment, it is particularly preferable to perform steam curing.

  The conditions for this steam curing are, for example, that the temperature is in the range of 40 to 90 ° C., and the curing time is preferably in the range of 6 to 48 hours.

  After curing the molded body, the molded body is dried. The drying method is not particularly limited, and examples include hot air drying and far-infrared drying. By drying the molded body, the ratio of water (water content) contained in the molded body can be adjusted. The moisture content of the molded body is preferably in the range of 3 to 20%. In this case, the molded body can be made light and difficult to break, and deformation such as warpage and shrinkage due to drying shrinkage of the molded body can be reduced.

In the present embodiment, the outermost portion 31 of the skin layer 3 is 20 mm ² by an appropriate method such as selection of components contained in the skin material, adjustment of the amount of components, adjustment of curing conditions, adjustment of the moisture content of the skin layer 3. Even if a force of about 135 N is applied, the strength can be adjusted so as not to break.

In particular, the absolute dry specific gravity of the skin layer 3 is preferably 0.8 or more. As a result, high strength is imparted to the outermost portion 31 of the skin layer 3, and it is possible to achieve strength that does not break even when a force of 135 N is applied per 20 mm ^{2 of} the outermost portion 31. The absolute dry specific gravity of the skin layer 3 is preferably 2.0 or less. In this case, the building board 1 can be lightened and the building board 1 can be easily handled. The absolute dry specific gravity of the skin layer 3 can be adjusted, for example, by changing the ratio of water, organic foam particles, and inorganic foam contained in the skin material.

In particular, the thickness of the outermost part 31 of the skin layer 3 is preferably 1.5 mm or more. As a result, high strength is imparted to the outermost portion 31 of the skin layer 3, and it is possible to achieve strength that does not break even when a force of 135 N is applied per 20 mm ^{2 of} the outermost portion 31. The thickness of the outermost part 31 is preferably 1/3 or less of the total thickness of the building board 1. In this case, ensuring the strength of the outermost part 31 and reducing the weight of the entire building board 1 by reducing the weight of the core layer 2 can be achieved.

  Furthermore, the outermost 31 described above can be obtained by any method such as adjustment of the kind and blending amount of the reinforcing fibers included in the core material and skin material, preparation of curing conditions for the uncured molded article, and preparation of the specific gravity of the building board 1. Can be achieved.

  In addition, the structure of the building board 1 is not restricted to what is shown in FIG. For example, the interface between the core layer 2 and the skin layer 3 may have an uneven shape. The uneven shape may be, for example, an uneven shape in which a plurality of uneven portions having a square cross section are arranged, a zigzag shape in which a plurality of uneven shapes having a triangular cross section are arranged, or a plurality of uneven portions having an arc shape in a cross section. A wave shape may be sufficient. In this case, delamination between the core layer 2 and the skin layer 3 due to the frost damage phenomenon can be suppressed.

  As in the building board 1 shown in FIG. 3, a plurality of hollow holes 7 may be formed in the core layer 2. That is, the building board 1 may have a hollow structure. When the building board 1 has a hollow structure, the building board 1 can be further reduced in weight.

  A sealer and a paint for surface finishing may be applied to the surface of the building board 1, that is, the surface of the skin layer 3, as necessary.

  Hereinafter, the manufacturing method of the building board 1 of this embodiment is demonstrated in detail.

  The building board 1 shown in FIG. 1 is manufactured by, for example, extruding a core material and a skin material with an extruder 10. FIG. 4 shows an outline of the extruder 10.

  The extrusion molding machine 10 of FIG. 4 includes a first extruder 11 and a second extruder 12. The first extruder 11 extrudes the skin material, and the second extruder 12 extrudes the core material. The first extruder 11 and the second extruder 12 are connected to the mold 100.

  As shown in FIG. 4, the mold 100 includes an inflow port 103 at the front end and an extrusion port 104 at the rear end. The inlet 103 is connected to the first extruder 11. For this reason, the skin material flows into the inlet 103 from the first extruder 11.

  FIG. 5 shows a schematic sectional view of the mold 100. The mold 100 includes an upper mold 101, a lower mold 102, a core 105, a flow path 106, a flow path 107, and a flow path 108. The upper mold 101 and the lower mold 102 are stacked so as to face each other in the vertical direction.

  A cavity is formed inside the mold 100. A core 105 is provided in the cavity. The flow path 106 is between the lower surface of the upper mold 101 and the upper surface of the core 105 that appear in the cross-sectional view of FIG. 5, and the flow path 107 is between the upper surface of the lower mold 102 and the lower surface of the core 105. It is. The channel 106 and the channel 107 are connected to the inlet 103. For this reason, the skin material flows through the channel 106 and the channel 107.

  Further, as shown in the sectional view of FIG. 5, the thickness of the core 105 gradually decreases from the vicinity of the inlet 103 toward the inlet 103. Further, the end of the core 105 on the side of the extrusion port 104 gradually decreases in thickness toward the extrusion port 104. The tip of the core 105 on the extrusion port 104 side is disposed so as to face the extrusion port 104. The upper surface of the tip portion of the core 105 is formed as a flat inclined surface 111 toward the tip, and the lower surface of the tip portion of the core 105 is formed as a flat inclined surface 112 toward the tip.

  As shown in the sectional view of FIG. 5, a flow path 108 is formed inside the core 105. This flow path 108 is connected to the second extruder 12. Specifically, the flow path 108 in the core 105 is connected to the second extruder 12 via the pipe 17. For this reason, the core material kneaded by the second extruder 12 flows into the flow path 108. A rectangular opening 110 that communicates with the flow path 108 is formed at the tip of the core 105.

  As shown in the cross-sectional view of FIG. 5, the flow path 106, the flow path 107, and the flow path 108 are joined at the extrusion port 104 side with respect to the flow path 106 and the flow path 107 in the mold 100. The part 109 joins. For this reason, the extrusion port 104 is connected to the channel 106, the channel 107, and the channel 108.

  Hereafter, the procedure in which the building board 1 is manufactured with said extrusion molding machine 10 is demonstrated.

  First, the skin material is introduced into the inlet 13 of the first extruder 11 shown in FIG. 4, and the core material is introduced into the inlet 15 of the second extruder 12 shown in FIG. The skin material and the core material are respectively conveyed while being kneaded by the screw 14 provided in the first extruder 11 and the screw 16 provided in the second extruder 12.

  Next, the core material flows from the second extruder 12 into the flow path 108 through the pipe 17. Further, the skin material flows from the first extruder 11 through the inlet 103 into the flow path 106 and the flow path 107.

  Next, the core material that has passed through the flow path 108 reaches the opening 110. The core material discharged from the opening 110 is formed into a plate shape in accordance with the shape of the opening 110. In addition, the skin material that has passed through the flow path 106 and the skin material that has passed through the flow path 107 merge at the merge portion 109. Thereby, the outer side of the core material formed into a plate shape is wrapped with the skin material.

  Next, the core material and the skin material are extruded from the extrusion port 104 while the core material is wrapped by the skin material. By cutting the core material and the skin material at an arbitrary length, an uncured molded body (green sheet) is formed. A building board 1 including the core layer 2 and the skin layer 3 is manufactured by curing and curing the uncured molded body.

  Moreover, when manufacturing the building board 1 which has a hollow structure as shown in FIG. 3, the hollow formation body 200 shown, for example in FIG. 6A and FIG. 6B is used. The hollow formed body 200 includes a main body portion 201 and a plurality of protruding rods 202. The plurality of protruding rods 202 are arranged in a line at a predetermined interval and are provided in parallel to each other. The dimensions of the plurality of protruding bars 202 are all the same. The hollow formed body 200 has a dimension that can be disposed inside the flow path 108.

  The hollow forming body 200 is provided, for example, in the flow path 108 of the core 105 shown in FIG. In this case, some of the plurality of protruding rods 202 protrude from the opening 110. A building board 1 having a hollow structure as shown in FIG. 3 is formed by providing a core 105 in which a hollow formed body 200 is provided in a flow path 108 in a mold 100 and performing extrusion molding using the mold 100. Is manufactured.

  Hereinafter, the present invention will be specifically described by way of examples.

(Examples 1-4, Comparative Examples 1 and 2)
A core material and a skin material were prepared by blending an inorganic main material, an inorganic admixture, an organic admixture, a reinforcing fiber, and water in the proportions shown in Table 1 below. In addition, the water content in Table 1 is the ratio of water to the total solid content in each of the core material and the skin material.

  Using the core material and the skin material, a molded body was produced using the first extruder 11, the second extruder 12, and the extruder 1 including the mold 100 shown in FIG. After this molded body was cured by steam curing at 60 ° C. for 24 hours, the moisture content was further adjusted to 10% by a dryer, thereby having dimensions of 480 mm in width, 16 mm in thickness, and 3100 mm in length. And the building board 1 provided with the core layer 2 and the skin layer 3 as shown in FIG. 1 was manufactured. The outermost part 31 of the building board 1 has a thickness shown in Table 1 below.

(Evaluation)
About the construction board 1 of Examples 1-4 and Comparative Examples 1 and 2, the absolute dry specific gravity of the core layer 2 and the skin layer 3 was measured by the Archimedes method. The results are shown in Table 1 below.

  About the building boards 1 of Examples 1-4 and Comparative Examples 1 and 2, the strength of the outermost part 31 was evaluated. In order to evaluate this strength, the following nail pull-out test was conducted.

  First, a nail having a body diameter of 2.4 mm, a head diameter of 5.0 mm, and a length of 45 mm was driven from the outermost part 31 of the building board 1 to penetrate. Next, with the building board 1 fixed, the tip of the nail was clamped and fixed with a chuck, and a load was applied from the head of the nail to the outermost portion 31 by pulling the chuck toward the tip of the nail. . Then, as shown in FIG. 2B, the maximum load applied to the outermost portion 31 was measured before the occurrence of a breakage in which the periphery of the portion where the nail was driven in the outermost portion 31 was depressed. As a result, the case where the maximum load was 135 N or more was judged as ◯, and the case where the maximum load was less than 135 N was judged as x. The determination results are shown in Table 1 below together with the maximum load value.

  As shown in Table 1, as for the building board 1 of Examples 1-4, the maximum load is 135 N or more. For this reason, the building board 1 of Examples 1-4 can ensure the intensity | strength of the outermost part 31 fully. On the other hand, the building board 1 of the comparative examples 1 and 2 whose maximum load is less than 135 N cannot ensure the strength of the outermost part 31.

  In particular, when the building board 1 of Example 3 in which the absolute dry specific gravity of the skin layer 3 is 0.80 and the building board 1 of Comparative Example 1 in which the absolute dry specific gravity of the skin layer 3 is less than 0.80, The strength of the outermost part 31 is higher in the building board 1 of Example 3.

  In particular, when the building board 1 of Example 4 in which the thickness of the outermost part 31 is 1.5 mm and the building board 1 of Comparative Example 2 in which the thickness of the outermost part 31 is less than 1.5 mm are compared, The strength of the outermost part 31 is higher in the building board 1.

That is, an embodiment satisfying the condition that “the absolute density of the skin layer 3 is larger than the absolute density of the core layer 2 and the outermost portion 31 has a strength that does not cause damage even when a force of 135 N per 20 mm ² is applied”. The building board 1 of 1-4 can fully ensure the intensity | strength of the outermost part 31 rather than the building board 1 of the comparative examples 1 and 2 which are not satisfy | filling these conditions. Therefore, the building board 1 of Examples 1-4 has a negative pressure applied to the building board 1 by a strong wind or the like, and even if a strong force is applied from the fixture 6 to the outermost part 31, the outermost part 31 is not easily damaged. Even when a strong force is applied to the outermost part 31 when the fixture 6 is driven into the outermost part 1, the outermost part 31 is not easily damaged.

1 Building Board 2 Core Layer 21 Side 3 Skin Layer 31 Outermost

Claims (2)

A core layer formed from a molding material containing a hydraulic inorganic material;
A skin layer that covers the core layer is formed from a molding material containing a hydraulic inorganic material,
The absolute dry specific gravity of the skin layer is larger than the absolute dry specific gravity of the core layer,
The skin layer includes an outermost portion on one surface facing the thickness direction of the core layer,
A building board having a strength that prevents the outermost portion from being damaged even when a force of 135 N per 20 mm ² is applied. The absolute dry specific gravity of the skin layer is 0.8 or more,
The building board, wherein the outermost thickness is 1.5 mm or more.

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