JP2009263969A - Manufacturing method of construction plate material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a construction plate material which has high nail-side resistance and nail-head penetrating force, which can sufficiently retain a nail or the like, and which can be used as a wall underlayer comprising a proof-stress wall. <P>SOLUTION: A wet mat is formed by a wet manufacturing method from slurry of which the essential ingredient is 20 to 60 wt.% of a mineral matter fiber, 10 to 20 wt.% of an organic matter fiber, 10 to 70 wt.% of an inorganic powder, and 10 to 25 wt.% of an organic binding agent-containing thermosetting resin. Then a single-layer wet plate material formed of the wet mat or a multiple-layer wet plate material can be obtained, and at least both layer sides of the multiple-layer wet plate material are formed of the wet mat. After drying the wet plate material to 20% or less of a moisture content in a temperature range where the thermosetting resin does not harden, the thermocompression press of the wet plate material is performed, and the organic binding agent is completely hardened. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a building board, and more particularly to a method for manufacturing by wet papermaking.

Conventionally, as an architectural board having excellent smoothness and high productivity, as shown in Patent Document 1, wet obtained by wet papermaking from a slurry containing mineral fiber, inorganic powder and binder as essential components There is known a building board material obtained by drying an inorganic board to a moisture content of 20% or less and then hot-pressing to completely cure the binder. And the material mainly contained mineral fiber as a fiber for obtaining bending strength, and an extremely small amount of organic fiber was added.
JP 2003-251617 A

  However, the above-mentioned conventional building board material has the property that the mineral fiber mainly contained as the fiber is “brittle”. Therefore, when this building board is fixed to the wooden shaft frame of a wooden house with nails, etc., when trying to use it as a wall base material constituting a bearing wall, the nail side resistance and the nail head penetration force are low. Etc. are difficult to hold sufficiently. As a result, there has been a problem that it cannot be used as a wall base constituting the bearing wall.

  The present invention has been made in view of the above points, and its object is to improve the method of manufacturing a building board material by increasing the nail side resistance force and the nail head penetration force of the building board material. Etc. can be sufficiently retained, and the building board material can be used as a wall base constituting the bearing wall.

  In order to achieve the above object, in the present invention, 10 to 20% by weight of organic fiber is included in the composition of the slurry before becoming a building board material.

  Specifically, in the invention of claim 1, 20 to 60% by weight of mineral fiber, 10 to 20% by weight of organic fiber, 10 to 70% by weight of inorganic powder, and thermosetting resin A wet mat is formed by wet papermaking from a slurry containing 10 to 25% by weight of an organic binder as an essential component, and at least the front and back layers are formed from the wet mat. A multilayer wet substrate is obtained. And after drying this wet board | plate material to the moisture content of 20% or less in the temperature range in which the said thermosetting resin does not harden | cure, it press-presses and hardens | cures an organic binder completely, It is characterized by the above-mentioned.

  According to the configuration of the present invention, a wet mat is formed from the slurry by wet papermaking, and a single-layer or multi-layer wet plate material is obtained from the wet mat. The wet board is dried to a moisture content of 20% or less within a temperature range where the thermosetting resin is not cured, and then the organic binder is completely cured by hot pressing to obtain a building board.

  At that time, since the organic fiber is contained in the slurry in an amount of 10 to 20% by weight, the manufactured building board material has sufficient nail side resistance force and nail swift penetration force to be used as a wall base material constituting the bearing wall. It will have something.

  As described above, according to the first aspect of the present invention, since the organic fiber is contained in an amount of 10 to 20% by weight, the nail side surface resistance sufficient for use as the wall base material constituting the bearing wall and the nail manifestation are sufficient. You can get a building board with power.

  Hereinafter, the best embodiment of the present invention will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or its application.

  FIG. 1 shows steps of a method for manufacturing a building board material according to an embodiment of the present invention. The manufacturing method of this embodiment includes a slurry generation step 1, a wet mat formation step 2, a wet plate material formation step 3, a drying step 4, and a hot-pressing step 5, and these steps 1 to 5 are performed in the order described.

(1) Slurry generation process In the first slurry generation process 1, a slurry containing mineral fibers, organic fibers, inorganic powders, and an organic binder containing a thermosetting resin is generated. . These mineral fiber, organic fiber, inorganic powder, and organic binder are dropped into water and stirred, and auxiliary additives such as a sizing agent and a flocculant are added to obtain a slurry.

(Mineral fiber)
The mineral fiber is added to obtain the bending strength of the building board and to suppress the expansion due to water absorption and moisture absorption.

  The mineral fiber is added in an amount of 20 to 60% by weight (20% by weight or more and 60% by weight or less). If it is less than 20% by weight, the bending strength is lowered. On the other hand, if it exceeds 60% by weight, the drainage at the time of papermaking deteriorates and a good wet mat cannot be obtained.

  Examples of the mineral fiber include rock wool, slag wool, mineral wool, glass fiber and the like, and these can be used alone or in combination.

(Organic fiber)
The organic fiber is added to obtain bending strength in the same manner as the mineral fiber, and to provide a nail side resistance force and a nail head penetration force sufficient for use as a wall base material constituting the bearing wall.

  The organic fiber is added in an amount of 10 to 20% by weight (10% by weight or more and 20% by weight or less). If it is less than 10% by weight, sufficient nail side resistance and nail head penetration force to be used as a wall base material constituting the bearing wall cannot be obtained, and if it exceeds 20% by weight, unevenness occurs during paper making. A good wet mat cannot be obtained.

  Examples of organic fibers include synthetic fibers such as polyester, polypropylene, and vinylon, wood fibers, and pulp, and these can be used alone or in combination.

(Inorganic powder)
The inorganic powder is added to ensure hardness. The inorganic powder is added in an amount of 10 to 70% by weight (10% by weight or more and 70% by weight or less). If the amount is less than 10% by weight, the desired hardness cannot be obtained. If the amount exceeds 70% by weight, the amount of mineral fiber and organic fiber is relatively reduced, and the desired bending strength cannot be obtained. .

  Examples of inorganic powders include calcium carbonate, aluminum hydroxide, microsilica, slag, and the like, and these can be used alone or in combination.

(Organic binder)
The organic binder is for binding mineral fibers, organic fibers, and inorganic fibers. For example, an isocyanate resin such as MDI (diphenylmethane diisocyanate), a thermosetting resin such as a phenol resin, a melamine resin, and an epoxy resin. It is essential and used in combination with a thermoplastic resin such as starch and polyvinyl alcohol. By using together a material that is gelatinized by heating in the presence of water such as starch, the mold can be retained and handled easily until the thermosetting resin is cured.

  The organic binder is added in an amount of 10 to 25% by weight (10% by weight or more and 25% by weight or less) in order to sufficiently bind mineral fiber, organic fiber, and inorganic fiber.

(2) Wet mat forming step In the next wet mat forming step 2, the produced slurry is wet-made with a long-mesh type or round net-type paper machine to form a wet mat.

(3) Wet plate material forming step In the subsequent wet plate material forming step 3, two wet mats are laminated to obtain a wet plate material composed of a laminate having a two-layer structure.

  In order to obtain shape retention and handling strength for the wet plate (laminated body), the wet plate (laminated body) is temporarily compressed at a predetermined pressure and a predetermined temperature (80 to 180 ° C.) with a heating roll or continuous press. May be.

(4) Drying step In the drying step 4, the moisture content is 20% or less in a temperature range (for example, a temperature of 80 to 250 ° C.) in which the thermosetting resin is not cured by, for example, a hot air dryer. Allow to dry. If the water content at this time exceeds 20%, the time of the hot press in the subsequent process becomes long, and the productivity is lowered. The moisture content here is
Water content = (weight before drying−total dry weight) / total dry weight × 100
And

(5) Hot-pressing step In the final hot-pressing step 5, the wet plate material (laminate) dried to the predetermined moisture content through the drying step 4 is hot-pressed at a predetermined pressure, temperature and time. The organic binder is completely cured to obtain a building board material.

Before the organic binder is completely cured in the hot-pressing step 5, an aqueous liquid or an oily liquid may be applied to the front and back surfaces of the wet plate or one (one side) thereof. This is because the flow of the binder is promoted, and the surface smoothness and surface hardness are improved. As the aqueous liquid, for example, water-soluble resins such as vinyl acetate emulsion and polyvinyl alcohol can be used in addition to fresh water. As an oily liquid, for example, an isocyanate-based or epoxy-based alcohol diluted product can be used. And as an application quantity of a liquid substance, 20-100 g / m < ² > is preferable per single side | surface. If it is less than 20 g / m ² , almost no effect is seen, and if it exceeds 100 g / m ² , it takes too much time for the coating operation.

  Since the building board thus obtained contains 10 to 20% by weight of organic fiber, it has sufficient nail side resistance and nail wiping power to be used as a wall base material constituting the bearing wall. Become.

  Incidentally, although not included in the present invention, in addition to the above-described steps, a method of pressing the obtained wet plate (laminated body) with a cold press and then releasing and drying with a dryer is also conceivable. However, in this method, when the organic fiber is contained in an amount of 10 to 20% by weight as in the present invention, the restoring force of the organic fiber is larger than that of the mineral fiber, so that the resulting product is greatly undulated. Therefore, it cannot be used as a plate material and is not practical.

(Other embodiments)
In the above embodiment, two wet mats are laminated to obtain a wet plate material composed of a laminate having a two-layer structure, but instead of a laminate in which these two wet mats are laminated, It may be a laminate in which three or more layers are laminated, and it is sufficient to obtain a multilayer wet plate material in which at least the front and back layers are made of a wet mat. Conversely, a single-layer wet plate made of a single-layer wet mat may be used.

  Next, specific examples will be described.

(Example)
35% by weight of rock wool as mineral fiber, 10% by weight of polyester fiber and 5% by weight of pulp as organic fiber, 32% by weight of calcium carbonate as inorganic powder, 10% by weight of starch, 5% by weight of phenol, Polyvinyl alcohol (2% by weight) and MDI (1% by weight) were dropped into water and stirred, and after adding a small amount of a sizing agent and a flocculant, paper was made to prepare two wet mats. A laminate having a two-layer structure was obtained by laminating these two wet mats. The moisture content of the laminate at this time was 80%. This laminate was temporarily pressed through a 6 mm-thickness distance bar by a hot press at 90 ° C. for 90 seconds. Subsequently, it dried for 10 minutes with a 150 degreeC dryer, and obtained the laminated body of 10% of water content. Finally, water of 50 g / m ² on one side was uniformly applied to each of the front and back surfaces of the laminate, and then pressed for 3 minutes at 200 ° C. through a 6 mm distance bar to obtain a building board material. .

(Comparative example)
35% by weight of rock wool as mineral fiber, 3.5% by weight of polyester fiber and 5% by weight of pulp as organic fiber, 38.5% by weight of calcium carbonate as inorganic powder, 10% by weight of starch as organic binder, phenol 5% by weight, 2% by weight of polyvinyl alcohol and 1% by weight of MDI were dropped into water and stirred. After adding a small amount of a sizing agent and a flocculant, paper was made to prepare two wet mats. These two wet mats were laminated to obtain a laminate having a two-layer structure (water content: 80%), and thereafter the same treatment as in the above example was performed.

(Measurement results of building board)
About the building board material obtained by the said Example and comparative example, the nail side resistance force and the nail head penetration force were measured. The nail side resistance was in accordance with the “woody cement board” nail side resistance test defined in JIS A5404. However, the nail was N50, and the displacement speed was 3 mm / min. On the other hand, the nail head penetration force was in accordance with NAIL WITHDRAWAL TEST defined in ASTM D1037. However, the nail was N50, and the displacement speed was 2 mm / min. The measurement results are shown in FIG. 2 that the nail side resistance force and the nail head penetration force of the example are significantly higher than those of the comparative example.

  In addition, using the building board material obtained in the above example, according to the "no load-bearing wall of wooden construction and its magnification performance test and evaluation work method" established by the Japan Building Research Institute and Building Evaluation Center, The magnification was measured. The nail was N50, the nail driving interval was 100 mm on all sides, the center was 200 mm, and the edge was 12 mm.

  As a result, the wall magnification was 3.4, and it was confirmed that the building board material of the present invention has excellent performance as a wall base constituting the bearing wall.

  INDUSTRIAL APPLICABILITY The present invention provides a building board material that has a high nail side resistance force and a nail head penetration force and can be used as a wall substrate constituting a bearing wall, and is thus extremely useful and highly industrially applicable.

FIG. 1 is a process diagram of a method for manufacturing a building board according to an embodiment of the present invention. FIG. 2 is a diagram showing the results of measuring the nail side resistance force and the nail head penetration force for the building board materials obtained in the examples and comparative examples.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Slurry production | generation process 2 Wet mat formation process 3 Wet board material formation process 4 Drying process 5 Hot-pressing process

Claims (1)

10-25 wt% organic binder comprising 20-60 wt% mineral fiber, 10-20 wt% organic fiber, 10-70 wt% inorganic powder, and thermosetting resin Forming a wet mat by wet papermaking from a slurry having the essential components as described above, to obtain a single layer wet plate made of the wet mat, or a multilayer wet plate made of at least the front and back layers of the wet mat,
The wet board is dried to a water content of 20% or less in a temperature range where the thermosetting resin is not cured, and then the organic binder is completely cured by hot-pressing. .

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