JPH07285193A - Reinforcing fiber-containing inorganic board and its manufacturing method - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a reinforcing fiber-containing inorganic plate material having high bending strength and few cracks, and its manufacturing method. [Structure] The plate material 2 containing the reinforcing fibers 3 is formed on the one plate surface side of the plate material 2 with a high density and is oriented in the longitudinal direction of the plate material.
It has a reinforcing fiber layer 2A, and has a second reinforcing fiber layer 2B oriented in the longitudinal direction of the plate and having a low density on the other plate surface side, and between the first and second reinforcing fiber layers 2A, 2B. It has an intermediate reinforcing fiber layer 2C oriented free or in the longitudinal direction of the plate material, and the layers 2A, 2B, 2C are integrated. In addition, the plate material 2 transfers the reinforcing fiber 3 to the sheet 4 side by dehydrating the slurry S in the hopper 7 to the lower side of the sheet 4 immediately below the hopper 7 and is oriented in the sheet longitudinal direction as the sheet 4 advances. The reinforcing fiber layer 2A is formed, while the second reinforcing fiber layer 2B in which the reinforcing fibers 3 are oriented in the sheet longitudinal direction is formed through the resistance of the gate 7B of the hopper 7, and the first and second reinforcing fiber layers are formed. In the middle of 2A and 2B, a third reinforcing fiber layer 2C having a free orientation or an orientation intersecting the longitudinal direction of the sheet is formed to form each of the layers 2 above.
It is made by integrating A, 2B and 2C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing fiber-containing inorganic plate material used for outer wall materials, roof tiles and the like, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, there is a flow-on type manufacturing method as a method of manufacturing a reinforcing fiber-containing inorganic plate material such as an outer wall material or a roof tile. This flow-on type manufacturing method has a relatively high solid content concentration of 20 to 45% and a single layer on a circular sheet having water permeability that advances a slurry containing reinforcing fibers in the longitudinal direction. Of the same thickness, and this slurry is decompressed and dehydrated by suction means provided on the lower surface of the sheet to form a continuous plate-shaped raw plate, which is cut to a predetermined size and then cured to obtain a plate-shaped plate. (See, for example, Japanese Patent Application Laid-Open No. 4-153004), the suction means connects a plurality of movable suction boxes on the lower surface side of the seat in the seat moving direction so as to move in synchronization with the seat. It is configured by setting.

In this flow-on system, unlike a papermaking method in which a thin slurry attached to a papermaking sheet is wound around a making roll many times (for example, JP-A-4-47905), a slurry having a relatively high concentration is prepared. Since it is suddenly supplied on the sheet in a desired thickness, there is an advantage that a building element in which delamination does not easily occur can be obtained.

[0004]

When a large number of movable suction boxes are connected in the sheet advancing direction to form the suction means, the water absorption holes provided in the top plate of the box cannot be provided too close to the edges, and therefore the movable suction boxes are movable. At both ends of the suction box in the seat advancing direction, the dehydration effect is inevitably lower than that at the center in the same direction.

However, in the conventional flow-on type manufacturing method, the slurry supplied onto the sheet is suddenly depressurized and dehydrated by the suction means composed of such a movable suction box group. The slurry thickness differs between the both end portions and the central portion, which may cause a so-called waviness phenomenon in which the slurry thickness periodically changes in the sheet advancing direction.

When the slurry whose supply thickness is cyclically changed in this way is dehydrated under reduced pressure by the suction means, the thickness of the raw plate after dehydration is also cyclically changed, and as a result, the thickness of the building plate material as the final product is also non-uniform. It becomes a cause to deteriorate the product quality. Further, in the past, since the slurry in the hopper is placed on the sheet without being dehydrated at the beginning of the supply, for example, when the water content at the time of blending is high and the consistency of the slurry is high, the shape of the slurry at the beginning of the supply Is likely to change, and the slurry supply thickness may change due to a slight vibration of the sheet, and this point also causes the corrugation phenomenon.

When the slurry in the hopper is directly supplied onto the sheet, when the specific gravity of the reinforcing fibers mixed in the slurry is small, the reinforcing fibers float up while the slurry stays in the hopper, and the reinforcing fibers rise on the sheet. The desired content of reinforcing fibers may not be reached when the slurry is deposited on the. Furthermore, the conventional fiber-containing inorganic board material produced by the flow-on method has an indeterminate orientation of the reinforcing fibers and has no directionality, and the aspect ratio of the fiber orientation (the fibers are oriented in the longitudinal direction of the board material is Vertical orientation, horizontal orientation is the orientation that intersects with the longitudinal direction, and horizontal-to-vertical ratio refers to the ratio) and is either vertical orientation or horizontal orientation. The bending strength of was not sufficient.

Therefore, according to the present invention, a reinforcing fiber-containing inorganic plate material in which the reinforcing fiber has a small aspect ratio and the reinforcing fiber is oriented in a substantially cross beam shape in plan view to enhance the bending strength, and the slurry supply thickness is An object of the present invention is to provide a manufacturing method capable of reliably preventing a waving phenomenon that periodically changes.

[0009]

The present invention achieves the above-mentioned object in a reinforcing fiber-containing inorganic plate material 2 in which reinforcing fibers 3 are joined and integrated in an inorganic layer 4 obtained by dehydrating and hardening a slurry S. In order to do so, the following technical measures are taken. That is, the reinforcing fiber-containing inorganic plate material of the present invention according to claim 1 has, on one plate surface side of the plate material 2, a high-density first reinforcing fiber layer 2A oriented in the plate material longitudinal direction, and On the plate surface side, there is provided a second reinforcing fiber layer 2B having a low density and oriented in the longitudinal direction of the plate material, and between the first and second reinforcing fiber layers 2A and 2B is free or has an orientation intersecting the longitudinal direction of the plate material. The intermediate reinforcing fiber layer 2C, and each of the layers 2
It is characterized in that A, 2B and 2C are integrated.

Further, according to the present invention, the hopper 7 having the gate 7B on the water-permeable sheet 4 which advances in the longitudinal direction.
In order to achieve the above-mentioned object, in the method for producing a reinforced fiber-containing inorganic plate material 2 in which the inorganic slurry S mixed with the reinforcing fibers 3 is supplied via, and the slurry S is dehydrated and cured below the sheet 4. The following technical measures are taken.

That is, in the method of the present invention according to claim 2, the slurry S in the hopper 7 is dehydrated to a position below the sheet 4 just below the hopper 7 to transfer the reinforcing fibers 3 to the sheet 4 side and the sheet 4 side. To form the first reinforcing fiber layer 2A oriented in the sheet longitudinal direction, while forming the second reinforcing fiber layer 2B in which the reinforcing fibers 3 are oriented in the sheet longitudinal direction through the resistance by the gate 7B of the hopper 7. In addition, in the middle of the first and second reinforcing fiber layers 2A and 2B, a third reinforcing fiber layer 2C having a free or orientation intersecting the sheet longitudinal direction is formed to integrate the layers 2A, 2B and 2C. It is a feature.

Further, in the method of the present invention according to claim 3, the means for dewatering the slurry S in the hopper 7 below the sheet 4 immediately below the hopper 7 is provided with an opening 7A of the hopper 7 having an open bottom. A support plate 17 with water absorption holes 17A that supports and guides the sheet 4 in the traveling direction of the sheet 4 with the opening 7A, and dehydrates the head height H of the slurry S in the hopper 7. It is characterized by that.

Further, in the method of the present invention according to claim 4, the means for dehydrating the slurry S in the hopper 7 to the lower side of the sheet 4 immediately below the hopper 7 is the opening 7A of the hopper 7 having an open bottom. It is a fixed suction box 8 having a support plate 17 with a water absorption hole 17A for supporting and guiding the sheet 4 in the traveling direction of the sheet 4 with the opening 7A.

Further, the method of the present invention according to claim 5 is characterized in that the slurry S in the hopper 7 is dehydrated by pressurizing it toward the sheet 4.

[0015]

The reinforcing fiber-containing inorganic plate material according to the present invention has a stronger bending strength because the reinforcing fiber 3 has a lateral-to-longitudinal ratio of less than 1 and is orientated in a grid pattern in a plan view. Further, according to the manufacturing method of the present invention, the slurry S retained in the hopper 7 is supplied onto the sheet 4 while being dehydrated below the sheet 4, so that the slurry S immediately after the supply has already been dehydrated to some extent. For this reason, it is harder and less likely to be deformed than when mixed.

Therefore, even if the sheet is then hung on the movable suction box group 5 having a different water absorption effect depending on the plane position or the sheet 4 is vibrated, the slurry thickness does not change so much. Further, when the slurry S sheet 4 accumulated in the hopper 7 is dehydrated below, the reinforcing fibers 3 are pulled toward the sheet 4, so that even the reinforcing fibers 3 having a low specific gravity can be reliably collected in the vicinity of the sheet 4. .

[0017]

Embodiments of the present invention will be described in detail below with reference to the drawings. 1A and 1B illustrate a manufacturing apparatus 1 for carrying out the method of the present invention and an inorganic plate material 2 containing reinforcing fibers which can be obtained by the method of the present invention. A plate material 2 in which reinforcing fibers 3 such as glass and pulp are integrally bonded to an inorganic layer 4 such as an inorganic material such as cement, silica sand, fly ash and an inorganic lightweight aggregate such as pearlite is provided on one plate surface side thereof. A first reinforcing fiber layer 2A having a high density of fibers 3 oriented in the plate material longitudinal direction and a second reinforcing fiber layer 2 having a low density of fibers 3 oriented in the plate material longitudinal direction on the other plate surface side.
The intermediate layer between B and the first and second reinforcing fiber layers 2A and 2B is formed by integrating the respective layers of the intermediate reinforcing fiber layer 2C in which the fibers 3 are in a free orientation or an orientation intersecting the longitudinal direction of the plate material.

In the first and second reinforcing fiber layers 2A and 2B, not only all of the fibers 3 are longitudinally oriented but also most of the fibers 3 are longitudinally oriented and some of them are horizontally oriented. May be present, the point is that it means that the amount of vertical alignment is larger than that of horizontal alignment,
On the other hand, in the intermediate reinforcing fiber layer 2C, free orientation means that the direction of the fiber 3 has at least one of vertical and horizontal directions, or cross orientation, and cross orientation means that there may be some oblique orientation. In any case, the intermediate reinforcing fiber layer 2C is sandwiched between the first and second reinforcing fiber layers 2A and 2B, so that the reinforcing fibers 3 are arranged in a vertical and horizontal cross girders in a plan view. 2, the bending strength is high.

With reference to FIG. 1 (A), a method for producing the above-mentioned reinforcing fiber-containing inorganic plate material 2 will be described with reference to the apparatus. The manufacturing apparatus 1 includes an endless sheet 4 having a water permeability and an upper surface to which slurry is supplied, and a large number of movable suction boxes 5 for depressurizing and dehydrating the slurry from a lower surface of the sheet 4 in a frame framed on the floor. An annular belt 6 advancing in contact with the upper surfaces of the left and right (width direction) ends of the sheet 4, a supply hopper 7 for supplying slurry to the upper surface of the sheet 4, and a sheet located below the hopper 7 and It is configured by providing a stationary fixed type suction box 8 that contacts the lower surface of 4.

The sheet 4 is formed by annularly forming a water-permeable long strip-shaped flexible member such as felt or woven cloth, which is guided by a plurality of guide rolls 9 and installed on the floor. Is driven so that the upper side circulates in the longitudinal direction (direction of arrow A in FIG. 1). Sheet 4
The front and rear parts of the frame are rotatably supported by large-diameter front and rear sprockets 11 and 12 which are rotatable about a horizontal axis 10 parallel to the seat width direction, and are conveyed around the sprockets 11 and 12. The movable suction boxes 5 are arranged on the outer peripheral side of the chain 13 and in the chain longitudinal direction.

The front sprocket 11 on the downstream side is rotationally driven via a chain by a motor provided on the upper part of the frame,
By the rotation of the front sprocket 11, the movable suction boxes 5 come into contact with the lower surface of the seat 4 and the seat 4 moves.
It circulates in the same direction and at the same speed. Suction rails having a hollow cross section are installed along the traveling direction of the chain 13 on the left and right sides of the upper end of each gate frame located between the front and rear sprockets 11 and 12, the inside of which is decompressed by a Nash pump or the like (not shown). The movable suction boxes 5 circulated by the sprockets 11 and 12 slidably move on the suction rails 14.

Each movable suction box 5 is composed of a hollow box body having a large number of water absorption holes on its top plate, and has long holes in the seat advancing direction communicating with decompression holes provided on the suction rails 14 on both left and right sides of the bottom plate. I have it. Therefore, the inside of each suction box 5 is depressurized at a substantially constant pressure due to the communication of the depressurization hole and the long hole while sliding on the suction rail 14, and the material supplied to the upper surface of the seat 4 is The water is vacuum-dewatered from the lower side of the sheet 4 through the water absorption holes of the suction box 5.

The belt 6 is for identifying the width of the slurry-like material supplied to the upper surface of the sheet 4, and is made of a material having water-tightness and elasticity such as synthetic rubber, and is shown in the figure. Although not shown, a projecting part having a rectangular cross section is provided on the upper surface in the center of the width direction of the strip-shaped part that comes into contact with the upper surface of the sheet 4 to form a T-shaped cross section. A pair of left and right pulleys 15 for guiding the belt 6 are provided separately from the lower part of each gate frame and the upper part of the gate frame located at the front and rear ends, and a guide roll 9 supporting the seat 4. 1
The belt 6 guided by 5 is driven by the drive motor at the same speed and in the same direction as the seat 4 so that the belt-shaped portions on both sides in the width direction of the seat 4 contact the upper surfaces of both ends in the width direction of the seat 4, It is moved circularly.

A plurality of press rolls 16 are continuously provided in the front-rear direction above the front end of the frame, and the material passing under the rolls 16 is subjected to depressurization dehydration by the movable suction box 5 as well as pressure reduction of each press roll 16. Is further dehydrated by. The hopper 7 that supplies the slurry S onto the sheet 4 is
It is arranged on the downstream side (front side) of the movable suction box 5, the bottom of the hopper 7 is an opening 7A, and the outlet on the lower one side has a gate 7B. A suction box 8 is fixed immediately below the hopper 7.

As shown in FIG. 2, the suction box 8 is composed of a top plate 17 having a large number of water absorption holes 17A, a side plate 18A which cooperates with the top plate 17 to form a hollow box chamber 18 therein, and the like. The hollow box chamber 18 can be decompressed by a pump 19 or the like, and here, the dehydration means 20 is provided.
The top plate 17 is a support plate that substantially prevents the slack of the sheet 4 and guides and supports the sheet 4 in the sheet advancing direction. When the sheet 4 advances in its longitudinal direction (i), the hopper 7
The slurry S staying in the sheet 4 is dehydrated by cooperating with the gate 7B and supplying the slurry S onto the sheet 4 to a constant thickness.

That is, the slurry S staying in the hopper 7 at the head height H dewaters the water in the slurry S by suction with the pump 19, and the fibers 3 in the slurry S are dewatered by the flow of the water by this dewatering. While moving to the sheet 4 side, most of the fibers 3 are vertically oriented by the progress of the sheet 4, while most of the fibers 3 on the surface side are also vertically oriented due to the resistance by the gate 7B. In the above, the fibers 3 are relatively free to move and oriented in the longitudinal, lateral, diagonal, or other directions.

Here, the dehydration of the slurry S and its layer thickness are almost fixed before reaching the movable suction box 5, and even if dehydrated by the movable suction box 5, the fibers 3 hardly move in this step. , Where the back side (sheet 4 side) has a high fiber density and is oriented vertically,
The surface side (gate side) has a low fiber density and is oriented in the longitudinal direction, and the intermediate layer is laminated with the fiber orientation being free orientation. In the movable suction box 5, dehydration is added and strip-shaped reinforcing fibers are added. It becomes a green plate, and this green plate is completely cured through the subsequent curing step and the like, and cut into a fixed size to obtain a plate material 2 shown in FIG. 1 (B).

Dehydration immediately below the hopper 7 is performed by the pump 19
Although forced dehydration (vacuum dehydration) is most desirable,
A support plate 17 having a large number of water absorption holes 17A as shown in FIG.
It is also possible to provide natural dehydration by providing the head height H of the slurry S. At this time, sewage and the like is collected outside the installation by the drainage guide means 21 such as a chute or a gutter. Further, the upper lid of the hopper 7 can be dehydrated more quickly and surely by adding a pressure means 22, such as a pressure plunger or a pump, in a closed state.

Next, a concrete example will be described. The cement composition was 47% by weight of cement, 40% by weight of silica sand as silica content, 12% by weight of pulp fiber as reinforcing fiber, and 1% by weight of expanded polystyrene particles. ~ 45% of the slurry S is adjusted, the slurry S is put into the hopper 7 from the chute, and the seat 4 is advanced in the arrow A direction, and the movable suction box 5 is also moved in the arrow A direction at the same speed as the sheet 4. Advanced.

The slurry in the hopper 7 is the sheet 4
And the gate 7B flow out to the upstream side, and the thickness is regulated by the gate 7B, and the sheet 4 is supplied onto the sheet 4 proceeding to the upstream side. At this time, the slurry S retained in the hopper 7 is depressurized and dewatered downward by the dewatering means 8 provided immediately below the hopper 7 and on the lower surface side of the sheet.
The sheet 7 is unevenly distributed in a high density on the side, and most of it is oriented in the vertical direction by the progress of the sheet 4. On the other hand, in the gate 7B, due to its resistance, it is oriented in a low density but in the vertical direction. The movable suction box 5 was made to reach the movable suction box 5 in a state where the fibers were oriented obliquely and laminated.

The slurry S immediately after being supplied to the hopper 7 has already been dehydrated to some extent, and is harder and less likely to be deformed than when it was mixed. Therefore, after that, even when the movable suction box 5 group having a different water absorption effect depending on the plane position is reliably prevented from being excessively changed in the slurry thickness, and when the sheet 4 is vibrated, the slurry thickness is not changed. The plate material 2 having the aspect ratio shown in Table 1 below could be obtained by the subsequent curing step and the like.

[0032]

[Table 1]

As is clear from Table 1 above, the aspect ratio is 1
It can be made smaller and the bending strength can be increased, and the fibers can be prevented from unidirectionally cracking in a plan view, and the second reinforcing layer has a low fiber density. Pressing became easy, cracks were prevented from occurring during pressing, and the finish was improved.

The bending strength in Table 1 was tested by cutting out each part as a core. Further, the horizontal / aspect ratio with parentheses in Table 1 shows the plate material manufactured by arranging the supply hopper on the movable suction box.

[0035]

As described in detail above, the reinforcing fiber-containing inorganic plate material according to the present invention has a high bending strength, few cracks, and a substantially constant layer thickness, which is useful as an outer wall material. Is. Further, according to the method of the present invention, it is possible to continuously produce the reinforcing fiber-containing inorganic plate material having the above-mentioned advantages.

[Brief description of drawings]

FIG. 1A is an overall configuration diagram of an apparatus used in a method of the present invention, and FIG. 1B is a perspective view of a plate material.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is an enlarged view of an essential part showing another embodiment.

[Explanation of symbols]

 2 Plate Material 2A First Reinforcing Fiber Layer 2B Second Reinforcing Fiber Layer 2C Intermediate Reinforcing Fiber Layer 4 Sheet 7 Hopper 7B Gate 8 Dehydrating Means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area E04F 13/14 102 B 9127-2E

Claims (5)

[Claims] 1. A reinforcing fiber-containing inorganic plate material (2) in which reinforcing fibers (3) are bonded and integrated in an inorganic layer (4) obtained by dehydrating and hardening a slurry (S), wherein the plate material (2) Has a high-density first reinforcing fiber layer (2A) oriented in the plate longitudinal direction on one plate surface side, and has a low density second oriented fiber layer (2A) oriented on the other plate surface side. It has a reinforcing fiber layer (2B), and an intermediate reinforcing fiber layer (2C) between the first and second reinforcing fiber layers (2A) and (2B) that is free or has an orientation intersecting the longitudinal direction of the plate material. ,
A reinforcing fiber-containing inorganic plate material, characterized in that the layers (2A), (2B), and (2C) are integrated. 2. An inorganic slurry (S) in which reinforcing fibers (3) are mixed through a hopper (7) having a gate (7B) on a water-permeable sheet (4) which advances in the longitudinal direction.
In the method for producing the reinforcing fiber-containing inorganic plate material (2), in which the slurry (S) is dehydrated below the sheet (4) and cured, the slurry (S) in the hopper (7) is supplied to the hopper (7). ) Immediately below the sheet (4) to dehydrate the reinforcing fiber (3) to the sheet (4) side and the first reinforcing fiber layer (2A) oriented in the longitudinal direction of the sheet as the sheet (4) advances. ), While said hopper (7)
The second reinforcing fiber layer (2B) in which the reinforcing fibers (3) are oriented in the longitudinal direction of the sheet is formed through the resistance of the gate (7B) of the second reinforcing fiber layer (2A) (2).
In the middle of B), a third reinforcing fiber layer (2C) having a free orientation or an orientation intersecting the longitudinal direction of the sheet is formed to form each layer (2A).
(2B) (2C) is integrated, The manufacturing method of the inorganic fiber board material containing a reinforcing fiber characterized by the above-mentioned. 3. A means for dewatering the slurry (S) in the hopper (7) to a position below the sheet (4) immediately below the hopper (7) is an opening (7) of the hopper (7) having an open bottom.
Water absorption hole (17A) for supporting and guiding the sheet (4) in the traveling direction of the sheet (4) between A) and the opening (7A).
The supporting plate (17) provided with the reinforcing fiber-containing inorganic plate material according to claim 2, wherein the supporting plate (17) is dehydrated at a head height (H) of the slurry (S) in the hopper (7). Production method. 4. A means for dehydrating the slurry (S) in the hopper (7) below the seat (4) immediately below the hopper (7) is provided with an opening (7) of the hopper (7) having an open bottom.
Water absorption hole (17A) for supporting and guiding the sheet (4) in the traveling direction of the sheet (4) between A) and the opening (7A).
The method for producing a reinforced fiber-containing inorganic plate material according to claim 2, which is a fixed suction box (8) having a supporting plate (17) attached thereto. 5. The production of a reinforcing fiber-containing inorganic plate material according to claim 3 or 4, wherein the slurry (S) in the hopper (7) is dehydrated by pressurizing it toward the sheet (4). Method.