JPH1179859A - Nonflammable board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonflammable board having a strength, a surface hardness, water resistance, resistance to refrigeration and defrosting, and flexibility, further having processing suitability for the improvement or the like of a design by processing the board to form a curved surface shape by a means of a secondary molding such as a hot pressing, and including no asbestos fiber. SOLUTION: This nonflammable board is obtained by suspending a mixture consisting essentially of 5-20 wt.% mineral fiber having <=1, 000 μm fiber length, 70-90 wt.% aluminum hydroxide having <=50 μm particle diameter, 3-13 wt.% binder comprising powder or emulsion type phenolic resin and acrylic resin in terms of solid, 0.5-2.0 wt.% polyolefin-based heat-sealable fiber having 1-5 mm fiber length, in water to provide an aqueous slurry, carrying out the paper- making of the slurry to provide a single layer wet board, and drying the wet board containing the phenolic resin in unhardened state, and has 1,000-5,000 g/m<2> weight and 2-10 mm thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a board having incombustibility, flexibility, strength, surface hardness, dimensional stability, water resistance and freeze-thaw resistance, which is used as a material for the inside and outside of a building. And a board adapted to the inner and outer wall materials.

[0002]

2. Description of the Related Art Conventionally, calcium silicate plate, slag cement plate, gypsum slag cement plate, pulp cement plate and the like have been used as incombustible inner and outer wall materials having bending strength, surface hardness and water resistance as inner and outer wall materials. . However, although this kind of non-combustible boards have good performance in strength, non-combustibility, etc., they are not at a satisfactory level in workability, nail retention, freeze-thaw resistance, etc. At present, it is used as a flat inner and outer wall except in cold regions because it lacks workability such as processing into a curved shape to enhance designability. Also, some boards contain asbestos fibers, and measures against carcinogens are also necessary, which limits the range of use.

[0003]

SUMMARY OF THE INVENTION The present invention is nonflammable and has strength, surface hardness, water resistance, freeze-thaw resistance, and flexibility.
It is another object of the present invention to provide a board that does not contain asbestos fibers, which has processability such as processing into a curved surface shape by means of secondary molding such as a heat press to enhance designability.

[0004]

As means for solving the above-mentioned problems, the invention of claim 1 is characterized in that 5 to 20% by weight of mineral fibers having a fiber length of 1000 μm or less, 70 to 90% by weight of aluminum hydroxide having a particle size of 50 μm or less, Alternatively, a binder composed of a phenolic resin and an acrylic resin in the form of an emulsion is mainly composed of 3 to 13% by weight of solid content and 0.5 to 2.0% by weight of a polyolefin-based heat-fusible fiber having a fiber length of 1 to 5 mm. The resulting mixture is suspended in water to obtain an aqueous slurry, and a wet board obtained by drying the slurry in a single layer and drying the phenolic resin in an uncured state is 1000 to 1000.
5000 g / m ² , a board having a thickness of ² to 10 mm,
According to a second aspect of the present invention, the board of the first aspect is used alone or a decorative face material is laminated via an adhesive sheet, and the binder is softened and hardened by a secondary molding means such as a hot press. A flat or curved board having excellent properties, strength, surface hardness, dimensional stability, water resistance, and freeze-thaw resistance was found. Hereinafter, components constituting the board of the present invention and a manufacturing method thereof will be described in detail below.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[Mineral fiber] The mineral fiber used in the present invention is a mineral fiber having an average fiber diameter of 3 to 7 µm, which is substantially free of shots and whose fiber length is adjusted to 1000 µm or less. Mineral fibers typically SiO ₂ 35 to 50 wt%, Al ₂ O ₃ 10~1
5 wt%, CaO15~35 wt%, MgO5~20 wt%, FeO0~7 wt%, MnO, TiO _2, K
Iron ore slag, chromium slag, nickel slag, and other iron slags containing 0 to 5% by weight of trace components such as ₂ O, Na ₂ O, and S; Granular cotton, such as slag wool and rock wool, obtained by melting a raw material obtained by blending natural stones in an electric furnace or a cupola furnace and fiberizing the raw material with a spinner comprising a high-speed rotating body. Such granular cotton has an average fiber diameter of 3 to
7 μm, a monofilament having a fiber length of 30 to 40 mm or less is aggregated to form a granular form having a particle size of about 5 to 50 mm.
Non-fibrillated particles called shots of at least
% By weight. A board obtained by using such mineral fiber granular cotton without treatment is not uniform, lacks smoothness, and has poor appearance performance due to the presence of pills and shots due to unfibrillation of short fibers, resulting in poor practicality. Absent. The present invention solves the above-mentioned problems by using a high-speed rotating blade to cut granular cotton dispersed in water by means of a pulper, a mixer, or the like, and then cut the fibers and shots in a stream of water flowing out from a cylindrical lower portion. Is introduced into a shot separator having a water sieving function to separate shots, and mineral fibers having an adjusted fiber length substantially containing no shots are used. The fiber length can be adjusted in the range of 100 to 3000 μm by varying the number of rotations of the high-speed rotating blades and the processing time. In general, when the rotation speed is high and the processing time is long, the fiber length becomes short. In the de-shot, a shot having a small particle diameter can be removed by reducing the flow rate of water, but the processing step becomes long and is not economical. It is economical to remove shots having a particle size of 100 μm or more, and a board having a uniform and good appearance can be obtained substantially without a negative effect due to shots. The blending ratio of the mineral fiber having substantially no shot in the adjusted fiber length is 5 to 20% by weight.
If the content is less than 10% by weight, the retention of the raw materials of the other main components in the papermaking process is poor, and the shape retention during the transfer of the wet board from the papermaking to the drying process is insufficient, and the appearance and strength, dimensional stability, fire resistance The reason is that a board having good performance such as properties cannot be obtained, and if it exceeds 20% by weight, the mixing ratio of other main components such as aluminum hydroxide described below decreases, and satisfactory incombustibility cannot be obtained. .

[Aluminum Hydroxide] Aluminum hydroxide, which is the second main component used in the present invention, is a component imparting incombustibility and fire resistance similarly to mineral fibers, and has a particle size of 50 μm or less. 70 to 90% by weight.
If the particle size exceeds 50 μm, the basis weight is 1000 g to 5000
This is due to the lack of uniformity in the thickness direction, retention on wet boards, and surface smoothness of the board obtained in the papermaking of the board g. The compounding ratio is 70% by weight.
If it is less, the board's incombustibility cannot be satisfied,
On the other hand, if the content exceeds 90% by weight, the mixing ratio of the mineral fiber and the binder described below decreases, and the strength, dimensional stability,
This is because satisfactory performance such as water resistance cannot be obtained.

[Polyolefin-based heat-fusible fiber] The polyolefin-based heat-fusible fiber, which is the third main component used in the present invention, can be used together with mineral fibers to improve the papermaking properties of the board from the papermaking to drying steps. The shape retention during transfer, and furthermore, in the drying step and the step of secondary molding using a dry uncured board, the heat-fusible fiber partially heat-fuses and acts as a bonding material for the board. It has the effect to show the effect. Such fibers include, for example, polyethylene fibers, polypropylene fibers or polyethylene / polypropylene composite fibers. As a type that is heat-fused while maintaining the fiber shape, it is preferable to use fibers in which polyolefins having different melting points are composited. Examples of such fibers include polyethylene-polypropylene composite fibers. The reason for limiting the fiber length to 1 to 5 mm is that if the fiber length is shorter than 1 mm, the papermaking property and the shape retention during transfer are insufficient, and if the fiber length is longer than 5 mm, the formation of the obtained board decreases. This is because a board having a smooth surface cannot be obtained. The reason for setting the blending ratio to 0.5 to 2% by weight is as follows.
If the amount is less than 0.5% by weight, cracks and the like are likely to occur in the obtained board which is not at a satisfactory level in terms of papermaking properties and transportability, and the yield is reduced. On the other hand, if it exceeds 2% by weight, nonflammability is impaired.

[Binder] The binder which is the fourth main component used in the present invention comprises a phenolic resin binder and an acrylic resin binder. As the phenolic resin, a novolak-type phenolic resin obtained by subjecting a phenol and an aldehyde to a condensation reaction at a temperature of 60 ° C. or higher using an acid or alkali catalyst, a powder type obtained by dehydration drying and pulverization with a resol-type phenol resin, or An emulsion type phenol resin emulsified with an emulsifier is applicable.
As the powder type phenolic resin, those having a softening temperature of 45 ° C. or more and a particle size of 100 to 500 mesh are preferable from the viewpoint of papermaking dispersibility. As the emulsion type phenol resin, an aqueous emulsion type containing a solid content of 40% by weight or more can be used.

The acrylic resin used in combination with the phenolic resin as the binder used in the present invention is methyl acrylate, methyl methacrylate and alkyl acrylate which have a glass transition point at room temperature to 100 ° C. and have a flexibility in a temperature range not lower than room temperature. Aqueous emulsion type containing a solid content of 20% by weight or more can be used. The binder composed of the phenolic resin and the acrylic resin is in the range of 3 to 13% by weight in terms of solid content, but if it is less than 3% by weight, the obtained board has good nonflammability, but strength and flexibility. If it is not at a satisfactory level in terms of water resistance, water resistance and dimensional stability, and if it exceeds 13% by weight, strength, flexibility, water resistance and dimensional stability will be good, but nonflammability will be impaired. %
Must be: Further, the mixing ratio of the acrylic resin is preferably in the range of 30 to 70% by weight based on the phenolic resin in view of the secondary molding processability of the dried and uncured board and the flexibility of the board.

The main components used in the present invention are as described above, and a fixing aid such as acrylamide and a sulfuric acid band and a water repellent such as paraffin wax, wax emulsion and silicone emulsion are added to the main component mixture. When added within the range of weight%, the water resistance is further improved. In addition, calcium carbonate, clay, and the like do not impair the purpose of the present invention.
Powdered inorganic fillers such as mica, talc, silica, magnesium hydroxide, vermiculite, perlite, and glass balloons, and lightweight aggregates can be appropriately added and blended. An aqueous slurry is obtained by suspending the raw material mixture comprising the above components in water, and a single layer having a basis weight of 1000 to 5000 g /
m ² , molded into a board having a thickness of ² to 10 mm, but the board obtained in this way has no components such as cellulose fiber, which have a negative effect on water resistance, etc. Therefore, performances such as water resistance, dimensional stability, and freeze-thaw resistance can be greatly improved.

In the method for producing a board of the present invention obtained by single-layer papermaking, it is necessary to satisfy the following conditions. First, an aqueous slurry having a concentration of 2 to 8% by weight obtained by mixing and dispersing a raw material mixture composed of the constituents of the present invention with water in a pulper or a mixing tank is used in a long net type, a circular net type, or a combined long net / circular net type (rotofore). Ma) Single-layer papermaking with a papermaking machine to produce a basis weight of 1
2,000 to 5,000 g / m ² , ² to 10 mm thick paper is formed into a board, and then the phenolic resin as a binder component is dried in an uncured state at a temperature of 120 ° C. or less by a multi-cylinder dryer, and the board is dried (undried). Cured board). Since the board is rich in flexibility, it can be dried by a multi-cylinder dryer.

In the dry board of the present invention, since the phenolic resin as a binder is in an uncured state, the dry board is laminated with a single layer or a decorative face material via an adhesive sheet such as a butyral-modified phenol resin sheet, Temperature 120-200
The secondary molding can be performed under the conditions of ° C., a press pressure of 5 to 30 kg / m ² , and a time of 10 to 30 minutes. Under these molding conditions, the acrylic resin as a binder softens, and the phenolic resin is cured while also melting the polyolefin fiber, so that it has processing suitability such as flat plate molding, embossed flat plate molding, and curved surface molding. Both the appearance and the shape have characteristics that enable molding requiring designability.

Accordingly, the board of the present invention has nonflammability, strength and flexibility at the stage of secondary molding, excellent dimensional stability, surface hardness, workability, water resistance, freeze-thaw resistance, and natural veneer. Decorative paper such as decorative paper, decorative film, etc. can be laminated, and boards with flat and curved shapes can be manufactured by hot press molding means, and when applied to the inner and outer walls and ceiling of buildings, walls and ceilings with excellent design properties Can be finished to the site.

[0014]

EXAMPLES Hereinafter, the method for producing a board of the present invention and the performance of a secondary molded article using the board will be described in detail with reference to examples. [Example 1] The preparation of raw materials was performed using a standard disintegrator (JIS P-8).
029) and 43.75 g of de-shot rock wool (average fiber length 500 μm) and P
3.8 g of E · PP composite fiber was added and disintegrated for 5 minutes. After 5 minutes, 153.16 g of aluminum hydroxide and phenol resin 8.
75 g was added and disintegrated for 1 minute. After the disintegration, the raw materials were transferred to another container, and 19.44 g (8.74 g of solid content) of an acrylic emulsion was added and dispersed by stirring. Next, a water repellent agent3.
65 g (1.10 g of solid content was added and the mixture was stirred and dispersed.
A sulfuric acid band was added to this raw material to adjust the pH to 4.5. The board is made of a square sheet machine (25 cm x 2
5 cm). At this time, a 55 mesh wire was used. The press was limited to coaching when creating the board. The board was dried in an oven at 105 ° C. for 2 hours to obtain a nonflammable board of the present invention.

[Example 2] The preparation of the raw materials was performed using a standard disintegrator (J
ISP-8029) and de-shoot rock wool (average fiber length 500 μm)
1.88 g and 3.28 g of the PE / PP composite fiber were put and disintegrated for 5 minutes. Five minutes later, 175.00 g of aluminum hydroxide and 8.75 g of phenol resin were added, and the mixture was disintegrated for one minute. After the disintegration, the raw materials were transferred to another container, and 19.44 g (8.74 g of solid content) of an acrylic emulsion was added and dispersed by stirring. Next, 3.65 g (solid content: 1.10 g) of a water repellent was added, and the mixture was stirred and dispersed. Add a sulfuric acid band to this raw material,
The pH was adjusted to 4.5. The board was formed by a square sheet machine (25 cm × 25 cm). At this time, the wire used was 55 mesh. Pressing was limited to coaching during board preparation. Dry the board in the oven 1
Drying was performed at 05 ° C. for 2 hours to obtain a noncombustible board of the present invention.

Example 3 The preparation of the raw materials was performed using a standard disintegrator (J
ISP-8029), de-shot rock wool (average fiber length 500 μm)
0.94 g and 3.28 g of the PE / PP composite fiber were put therein and disintegrated for 5 minutes. Five minutes later, 192.50 g of aluminum hydroxide and 4.38 g of phenol resin were added and disintegrated for one minute. After disaggregation, the raw materials were transferred to another container, and 14.56 g (6.56 g of solid content) of an acrylic emulsion was added thereto, followed by stirring and dispersion. Next, 3.65 g (solid content: 1.10 g) of a water repellent was added, followed by stirring and dispersion. Add a sulfuric acid band to this raw material,
The pH was adjusted to 4.5. The board was formed by a square sheet machine (25 cm × 25 cm). At this time, a 55 mesh wire was used. The press was limited to coaching when creating the board. Dry the board in the oven 1
Drying was performed at 05 ° C. for 2 hours to obtain a noncombustible board of the present invention.

[Examples 4 to 6] The non-combustible boards of the present invention having the basis weight and thickness shown in Table 2 were obtained by changing the pressing conditions using the components of Example 2.

Comparative Examples 1 to 3 Comparative boards were obtained in the same manner as in Example 1 using the components shown in Table 3.

The performance of the non-combustible board of the present invention obtained in Examples 1 to 3 was measured and is shown in Table 1.

[0020]

[Table 1]

The performance of the non-combustible boards of the present invention obtained in Examples 4 to 6 was measured and is shown in Table 2.

[0022]

[Table 2]

The performances of the boards obtained in Comparative Examples 1 to 3 were measured and are shown in Table 3.

[0024]

[Table 3]

[0025]

Example 7 A dried but uncured board of Example 2 was applied to a polyvinyl butyral-modified phenolic resin-based adhesive sheet (thickness: 20).
μm) and natural veneer such as white oak (0.2 m thick)
m) were laminated and subjected to heat press molding at 150 ° C., 20 kg / cm ² for 20 minutes using a hot plate having a flat plate shape and a curved surface shape of R = 300. The resulting board was finished in a flat and curved shape with natural veneer decorative paste, and was nonflammable and excellent in design. The nail retention was also good.

[0026]

Comparative Example 4 A comparative board was obtained in the same manner as in Example 2 except that aluminum hydroxide having an average particle size of 100 μm was used. This board was poor in papermaking properties, in particular, the composition in the thickness direction was non-uniform, the appearance was poor, and the strength and flexibility were about 1/2 to 2/3 of the non-combustible board of the present invention obtained in Example 2.

[Test Method] Fire protection: Evaluated according to JIS A-1321. Flexural strength: evaluated according to JIS A-6307. Water coverage: 24 hours immersion of sample at 30 cm below water surface Freezing and thawing resistance: -20 ° C in air, 2 hrs frozen, 10 ° C in water
Freezing and thawing resistance was evaluated by delamination and appearance abnormality (cracks, cracks) on the substrate with 2 cycles of thawing as one cycle.

[0028]

As is clear from the above description, the board manufactured by the method of the present invention has a secondary formability, a uniform and good appearance, and a non-flammable and flexible basis weight of 1000 to 1000.
The production of a board of 5000 g / m ² became possible. or,
A board obtained through secondary molding by means such as a hot press has excellent properties such as nonflammability, strength, water resistance, freeze-thaw resistance, dimensional stability, and surface hardness. In addition, it is possible to provide a board suitable for construction of ceilings, inner and outer walls, etc. of a building where design is required, which can be processed into a curved shape laminated with a decorative surface material.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C08J 5/10 CFB C08J 5/10 CFB

Claims (2)

[Claims] 1. A mineral fiber having a fiber length of 1000 μm or less.
Aluminum hydroxide 7 having 20% by weight and a particle size of 50 μm or less
0 to 90% by weight, 3 to 13% by weight of a solid material of a binder made of a phenolic resin and an acrylic resin in powder or emulsion form, and a polyolefin-based heat-fusible fiber having a fiber length of 1 to 5 mm 0.5 to 2 An aqueous slurry is obtained by suspending a mixture containing 0.0% by weight as a main component in water, and a wet board obtained by forming the slurry into a single layer and drying the phenolic resin in an uncured state is obtained.
g / m ² , a board having a thickness of ² to 10 mm. 2. A non-combustible and flexible material obtained by laminating the board according to claim 1 alone or by laminating a decorative surface material via an adhesive sheet and softening and curing the binder by secondary molding means such as a hot press. Flat or curved board with excellent strength, surface hardness, dimensional stability, water resistance and freeze-thaw resistance.