JP2825696B2 - Manufacturing method of inorganic building board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an inorganic building board used as a base material for an inner wall or the like, and in particular, has a performance almost equivalent to a gypsum board, is lighter than a gypsum board, and is manufactured with simple equipment. The present invention relates to a method for producing an inorganic building board that can be made.

[0002]

2. Description of the Related Art Generally, as a base material for an inner wall or the like, a nail holding force, a bending strength, an impact strength and a fire resistance of a certain value or more are required.
It is required to have performances such as water resistance, moisture resistance, and cutting performance. For this reason, a gypsum board has been conventionally used, but the gypsum board has a specific gravity of 0.74 or more, and a certain thickness is required in terms of bending strength, and is a base plate. They are often used in large versions, and are too heavy for transport and construction. Further, the production of gypsum board requires many large-scale facilities such as a firing furnace, a forming machine, and a drying furnace.

[0003] In order to solve one of the above disadvantages, for example, a lightweight high-strength inorganic plate and a method for producing the same are disclosed in, for example, JP-A-56-41880 or JP-A-56-41881. As a result, the bending strength, the water absorption and the like are improved.

[0004]

However, in the above-described method, the weight is reduced by only about 10% in weight, and there is a problem that it is still heavy and is inconvenient for transportation and construction.

[0005] In view of the above problems, the present invention provides a method for manufacturing an inorganic building board, which has almost the same performance as gypsum board and can provide an inorganic building board lighter than a gypsum board with simple manufacturing equipment. The purpose is to:

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for uniformly dispersing a mixture containing mineral fibers, an inorganic powder, and a powdered synthetic resin binder as essential components. Is formed, and then a mineral fiber, a hard inorganic foam, and a mixture containing a powdered synthetic resin binder as essential components are evenly spread on the upper surface of the lower layer portion to form a middle layer portion,
On the upper surface of the middle layer, a mixture containing mineral fiber, inorganic powder, and powdered synthetic resin binder as essential components is evenly sprayed to form an upper layer. And a method for producing an inorganic building board.

The mineral fibers forming the lower layer include, for example, rock wool, slag wool, mineral wool,
Glass fiber and the like can be mentioned, and these alone,
Alternatively, two or more kinds can be used in combination. And
The composition ratio of mineral fibers in the lower layer is 20 to 60% by weight.
It is preferred that When the content is 20% by weight or less, the form of the mat cannot be maintained, and therefore, the inorganic powdery material described later cannot be held, and the bending strength as the final inorganic building board is low. If there is, the amount of the inorganic powder added becomes small, and the desired surface hardness and overall hardness as the base plate cannot be obtained.

The inorganic powder forming the lower layer is used to increase the hardness and to increase the screwing performance while maintaining fire resistance. For example, calcium carbonate, silica sand, micro silica, slag, aluminum hydroxide And the like. The composition ratio of the inorganic powder in the lower layer portion is
The content is preferably 30 to 70% by weight based on the relative proportion to the mineral fiber. The particle size of the inorganic powder is about 1
The strength is the largest when 50 μm particles are used, but those having an average particle diameter of 20 μm to 300 μm can be used.

The powdery synthetic resin binder forming the lower layer portion is
It is for linking and integrating the mineral fiber and the inorganic powdery material, and examples thereof include powdery synthetic resins such as melamine resin and phenolic resin. These may be used alone or in combination of two or more. it can. The composition ratio of the powdery synthetic resin binder in the lower layer is preferably 15% by weight or less. If the content is 15% by weight or more, there is a possibility that the specification as a quasi-noncombustible material may be deviated.

Further, in addition to the powdery synthetic resin, pulp, synthetic fiber,
A sizing agent, a flocculant and the like are added.

In general, the more organic fibers, the better the bending strength. Therefore, it is effective in terms of strength to mix organic fibers such as pulp into a part of the mineral fibers constituting the lower layer. It is also effective in terms of cost. In addition, in order to obtain an inorganic building board as a noncombustible material, it is necessary to make the total amount of organic components 7% by weight or less,
Since the total amount of the binder is regulated, it is necessary to add a larger amount of mineral fiber than the quasi-noncombustible material to obtain a certain strength.

The mixture forming the lower layer can be obtained by uniformly mixing the mineral fiber, the inorganic powder, the binder for the powdered synthetic resin, and the like. (Less than about 20% by weight) of water. The sprayed water has the effect of facilitating the flow of the binder and improving the heat conduction to the middle layer during hot pressing.

The mixture forming the lower layer is uniformly spread on the conveyor, and the method of spraying can be arbitrarily selected from existing methods.

The middle layer is formed from mineral fibers, rigid inorganic foam, and a powdered synthetic resin binder. Among them, the mineral fiber forming the middle layer part is for connecting hard inorganic foams described later, and examples thereof include rock wool, slag wool, mineral wool, glass fiber, and the like. They can be used alone or in combination of two or more. Mineral fibers must be added in an amount of at least 20% by weight or more in order to connect the hard inorganic foam. However, if the mineral fiber is too large, the amount of the hard inorganic foam to be added becomes relatively small and the weight cannot be reduced. It is preferably at most 60% by weight.

The hard inorganic foam forming the middle layer is for reducing the weight while maintaining the compressive strength, and examples thereof include pearlite, shirasu foam, silica flower, glass foam and the like. Or in combination of two or more. The composition ratio of the hard inorganic foam in the middle layer is preferably 30 to 70% by weight. When the content is 30% by weight or less, the strength is improved because the ratio of the mineral fibers is relatively increased, but the effect of lowering the specific gravity is not obtained. Is small, and the connection between the hard inorganic foams becomes insufficient.

The powdery synthetic resin binder for forming the middle layer is for linking and integrating the hard inorganic foam and the fibrous material, and examples thereof include powdery synthetic resins such as melamine resin and phenol resin. These can be used alone or in combination of two or more.

In order to obtain an inorganic building board as a quasi-incombustible material, the total amount of organic components in the middle layer is preferably 15% by weight or less. For this reason, it is necessary to consider that the total amount of the organic components including the powdery synthetic resin binder is also in the above-mentioned range even in the middle layer. Further, in order to obtain an inorganic building board as a non-combustible material, it is necessary to make the total amount of organic components 7% by weight or less as in the case of the lower layer portion described above.
Therefore, it is necessary to add a larger amount of mineral fibers than the quasi-noncombustible material.

The mixture for forming the middle layer may be a simple mixture of the mineral fiber, the hard inorganic foam, the powdered synthetic resin binder, and the like. An amount (up to about 20% by weight) of water may be mixed while spraying. Then, the mixture forming the middle layer portion is sprayed on the upper surface of the lower layer portion so as to have a uniform thickness. The method of spraying can be arbitrarily selected from existing methods.

Next, the mixture forming the upper layer portion is the same as the mixture forming the lower layer portion, but is not necessarily the same, and the material, composition, and thickness may be varied as necessary. . Then, the mixture forming the upper layer portion is uniformly sprayed and laminated on the upper surface of the middle layer portion deposited on the lower layer portion, thereby obtaining a laminate.

The step of compressing and integrating the laminate in a heated state is a step of melting and curing the binder and extruding air between the particles to make them adhere to each other. Biting into each other promotes integration of the lower layer, the middle layer and the upper layer.

[0021]

EXAMPLES (Example 1) 40 parts by weight of rock wool, 40 parts by weight of calcium carbonate,
As a binder, 15 parts by weight of powdered phenol, 5 parts by weight of pulp, and a small amount of a sizing agent were mixed while spraying 15% by weight of water with respect to the total weight of the above-mentioned composition to obtain a mixture. As shown in FIG. 1, the lower layer 3 was formed by spraying the mixture from the first hopper 1 onto the conveyor 2 to a thickness of 8 mm.

On the other hand, 35 parts by weight of rock wool, 45 parts by weight of perlite, 15 parts by weight of powdered phenol, 5 parts by weight of pulp, and a small amount of a sizing agent were mixed with 15% by weight of water based on the total weight of the above composition. The mixture was sprayed and mixed to obtain a mixture, and the mixture was sprayed from the second hopper 4 onto the upper surface of the lower layer 3 to form a middle layer 5 having a thickness of 17 mm.

Next, a mixture having the same composition as that of the lower layer 3 is sprayed on the upper surface of the middle layer 5 from the third hopper 6 to a thickness of 8 m.
m by forming the upper layer part 7,
After obtaining the deposit 8 of this, the deposit 8 is
/ Cm ^{2 with} a continuous belt press 9 to press and integrate to a total thickness of 9 mm, and cut it to an appropriate length with a cutter 10 to obtain an inorganic building board 11 having an overall specific gravity of 0.45, which was used as a sample.

Example 2 45 parts by weight of rock wool, 45 parts by weight of calcium carbonate,
As a binder, 10 parts by weight of powdered phenol and a small amount of a sizing agent were mixed while spraying 15% by weight of water with respect to the total weight of the above-mentioned composition to obtain a mixture, as shown in FIG. Was spread on the conveyor 2 so as to have a thickness of 12 mm, and passed through a leveling roll 12 to form a lower layer portion 3 having a thickness of 12 mm.

On the other hand, 40 parts by weight of rock wool, 50 parts by weight of perlite, 10 parts by weight of powdered phenol, and a small amount of a sizing agent were added in an amount of 15 parts based on the total weight of the composition.
Weight percent water while mixing to obtain a mixture,
The mixture was sprayed from the hopper 4 onto the upper surface of the lower layer portion 3 so as to have a thickness of 20 mm, and passed through a leveling roll 13 to form a middle layer portion 5 having a total thickness of 32 mm.

Next, a mixture of the same composition obtained in the same manner as the lower layer 3 is sprayed on the upper surface of the middle layer 5 from the third hopper 6 to a thickness of 12 mm to form the upper layer 7. After obtaining a deposit 8 having a total thickness of 44 mm, the deposit 8 is pressed and integrated with a continuous belt press 9 at 180 ° C. and 5 kg / cm ² until the total thickness becomes 12 mm. Cut to length and overall specific gravity 0.40
Was obtained as a sample.

Comparative Examples Commercial gypsum boards having the same outer dimensions as those of Examples 1 and 2 were used as samples of Comparative Examples 1 and 2, respectively.

Test Examples The results of tests performed on each sample of the inorganic building boards obtained in Examples 1 and 2 and commercially available gypsum boards (Comparative Examples 1 and 2) are shown below. Example 1 Comparative Example 1 Example 2 Comparative Example 2 Dimensions 910 × 1820 910 × 1820 910 × 1820 910 × 1820 Thickness 9 9 12 12 Specific gravity 0.45 0.74 0.40 0.74 Weight per sheet (kg) 6.7 11.0 7.9 14.7 songs Bending strength (kgf / cm ² ) 50 50 45 40 Bending strength after water absorption (kgf / cm ² ) 8 6 7 6 Surface hardness (kgf / cm ² ) 170 220 150 220 Visible penetration (kgf) 16 27 16 30 Fire protection Semi-combustible pass Semi-combustible pass Non-combustible pass Non-combustible pass

The test results were obtained based on the following method. Flexural strength: based on JIS 5907-1977. Flexural strength after water absorption: After immersion in water for 24 hours, JIS
Based on the test method according to 5907-1977. Surface strength: Based on JIS HARDNESS TESTER. Screw penetration force: Based on a test method according to JIS A5910. Fire protection: Based on JIS A1321.

As is apparent from the above measurement results, the specific gravities of Examples 1 and 2 were about 40, respectively, compared with Comparative Examples 1 and 2.
% Or less. The fact that the specific gravity is smaller than 40% means that
For example, when the standard size gypsum board is about 11 kg, the inorganic building board according to the present invention of the same size is 6.
It will be around 7kg. For this reason, in the case of a gypsum board, even if only about half of the loadable capacity of a truck or the like is available due to weight restrictions, the inorganic building board of the present application can load the full loadable capacity of a truck or the like. As a result,
Not only can logistics costs be greatly reduced, but also manual transportation and assembly work to the construction site becomes easier. In addition, since the bending strengths of Examples 1 and 2 were almost equal to those of Comparative Examples 1 and 2, it was found that, similarly to the gypsum board, they did not easily deform and were easy to use.

Examples 1 and 2 are smaller in surface hardness and screw penetration force than Comparative Examples 1 and 2. However, in general, when the surface hardness is 150 (kgf), dents and the like hardly occur. No problem. Further, the screw penetration force is required to be at least 2.5 times the weight of the inorganic building board. However, since the inorganic building board according to the present invention itself is lightweight, there is no practical problem in this respect. Therefore, it was found that the inorganic building board according to the present application can be used almost as well as a commercially available gypsum board, and is about 40% or more lighter than a commercially available gypsum board.

[0032]

As is apparent from the above description, according to the method for manufacturing an inorganic building board according to the present invention, a lightweight middle layer is sandwiched between a hard and dense upper layer and a lower layer. The resulting inorganic building board is obtained. Therefore, according to the present invention, an inorganic building board having substantially the same performance as gypsum board and lighter than gypsum board can be obtained. Further, according to the manufacturing method of the present invention, in the manufacturing process, large-scale manufacturing equipment such as a firing furnace, a forming machine, and a drying furnace required for manufacturing the gypsum board is unnecessary. Further, although a small amount of water is used, since the whole is of a dry type, the heat and pressure equipment can be small, so that it can be manufactured with simple manufacturing equipment. In particular, since all layers are formed by a dry method, a paper machine or the like is not required as compared with a case of manufacturing by a wet method, and drying time and drying cost can be reduced, and manufacturing can be performed at low cost. And even when pressed during molding, the hard inorganic foam itself of the intermediate layer is not compressed,
The voids located around the hard inorganic foam are filled, and the hard inorganic foams or the hard inorganic foam and the mineral fibers are in close contact with each other. For this reason, the deformation of the spring bag or the like hardly occurs, and sufficient strength can be obtained even with a small amount of resin, so that there is an effect that a lightweight and high-strength inorganic building board can be obtained.

[Brief description of the drawings]

FIG. 1 is a process chart showing Example 1 according to the present invention.

FIG. 2 is a process chart showing Example 2 according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 1st hopper, 2 ... Conveyor, 3 ... Lower part, 4 ... Second hopper, 5 ... Middle part, 6 ... Third hopper, 7 ... Upper part, 8 ... Laminate, 9 ... Continuous belt press, 11 ... Inorganic building boards.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-285078 (JP, A) JP-A-54-117520 (JP, A) JP-A-2-279536 (JP, A) JP-A-4- 125106 (JP, A) JP-A-51-56824 (JP, A) JP-A-55-71139 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) C04B 32/00 B28B 1 / 16

Claims (1)

(57) [Claims] 1. A lower layer is formed by uniformly spraying a mixture containing mineral fibers, an inorganic powder, and a powdered synthetic resin binder as essential components. Then, a mineral fiber, a hard inorganic foam, And, a mixture containing a powdered synthetic resin binder as an essential component is evenly sprayed on the upper surface of the lower layer portion to provide a middle layer portion,
On the upper surface of the middle layer, a mixture containing mineral fiber, inorganic powder, and powdered synthetic resin binder as essential components is evenly sprayed to form an upper layer. A method for producing an inorganic building board, characterized in that: