KR20020076428A - A gypsum board having fire resistance - Google Patents

Abstract

PURPOSE: Provided are refractory gypsum boards with improved hardness, fireproofing and reinforcing effect by adding ceramic fibers and silica to conventional gypsum boards. CONSTITUTION: The refractory gypsum boards comprise 1-5pts.wt. of ceramic fibers based on Al2O3-SiO2 or Al3O3-SiO2-ZrO2, being safe in a range of 1000-1400deg.C, 5-15pts.wt. of SiO2 having 0-30% water and up to 100mesh size, 60-95pts.wt. of gypsum hemihydrate, 1-7pts.wt. of gypsum hardeners such as Al2(SO4)3, K2SO4 and gypsum hydrate, 0.2-2pts.wt. of starch, and optionally 0.1-10pts.wt.(based on 100pts.wt. of gypsum board) of glass fibers for improving strength of gypsum boards.

Description

Fireproof Gypsum Board {A gypsum board having fire resistance}

The present invention relates to a refractory gypsum board, and more particularly, to manufacture a refractory gypsum board by mixing a certain amount of ceramic fibers and silica powder when manufacturing a refractory gypsum board used as a building material, compared to conventional products The present invention relates to a fireproof gypsum board that is robust and has excellent fire resistance, reinforcement, and the like.

In general, fireproof gypsum board is used in a field where fire resistance is particularly required among gypsum boards that are installed in the main structural part of a building, such as a fireproof building, a sound insulation partition wall, or an elevator hall partition wall.

Refractory gypsum board is installed in the main structural parts such as partitions, columns, beams, etc. of the building to protect buildings and human life in the event of a fire. It prevents it from becoming. The propagation degree of flame depends on the fireproof performance of gypsum board and the system of gypsum board construction. Especially, considering the light weight, convenience of construction, and economic efficiency, the propagation performance of gypsum board itself determines the propagation degree of flame.

Conventional gypsum board used aluminum sulfate, sulphate sulfate, Gypsum dihydrate fine powder and the like as Gypsum hemihydrate and hardening accelerator, starch, fiber material, admixture as adhesion aid, and separately to impart fire resistance. Vermiculite, clay, glass fibers or other inorganic fibers were added as an adjuvant and mixed with calcined gypsum to produce a fire-resistant gypsum board.

However, vermiculite added to impart the fire resistance is mainly used expanded vermiculite or unexpanded vermiculite. In the case of expanded vermiculite, the thermal insulation effect of preventing heat transfer to the inside when exposed to flame is excellent, but the plaster is There is a problem that can not compensate for the crack as it shrinks. In the case of unexpanded vermiculite, the interlayer water of the vermiculite having a three-layered layered structure escapes when exposed to high temperature, causing the expansion of swelling under water vapor pressure. However, if the particle size, particle size distribution and input amount are not put in proportion to the degree of gypsum shrinkage, the gypsum board itself is stressed by the expansion force, causing easy cracking and weakening of fire resistance. Therefore, when the unexpanded vermiculite is added to provide fire resistance, it may have an adverse effect without great care.

Bentonite is mainly used as a clay refractory material, and the main mineral is montmorillonite, which is a viscous clay having a strong viscosity generated by decomposition of the glass component of volcanic ash. The clay added to the refractory gypsum board itself is sinterable at 800 ° C. or higher, which combines with gypsum to maintain shape at high temperatures and not to collapse easily. However, when clay is added, it causes cracks as the temperature rises, so that the shrinkage force and sintering performance are so high that the cracks are large and cracks do not occur in the steel studs where the gypsum board is fixed. There is a defect that occurs. Due to this cracking property, when used in combination with gypsum, the fire resistance is not constant and the fire resistance in the center of the gypsum board is often weakened. In addition, clays have disadvantages such as supply and demand problems due to the decrease in strength of gypsum hardening body due to the increase in the amount of coma due to the viscous force during molding and the high price and dependence on imports.

Glass fiber is mainly applied as a reinforcing material. It is effective mainly at low temperature, but its function is weak at high temperature necessary for fire resistance test. Particularly, the reason why glass fiber is added to the gypsum board is that shrinkage occurs due to moisture escape in the gypsum when the gypsum hardener is heated. In this case, the glass fiber acts as a binder to provide a reinforcing function to maintain the shape of the gypsum board. The heat-resistant temperature of the glass fiber is 800 ℃, but in the case of the refractory heating test, it rises to 842 ℃ after 30 minutes, and thus, the effect is lost. In general, when the refractory heating time is 1 hour, 925 ℃, 10 hours after 2 hours, the glass fiber is limited as a reinforcing material in the refractory test.

As such, the conventional refractory gypsum board is composed of vermiculite, clay, glass fiber, gypsum and other admixtures. Although gypsum board manufactured by injecting vermiculite, clay, or glass fiber is improved in fire resistance performance compared to general gypsum board without refractory auxiliary materials, it is difficult to handle raw materials and constitutes a fire resistant system due to the limitation of fire performance. In order to do this, there is an inevitable problem of increasing the thickness of the wall or increasing the number of layers.

As such, the conventional fireproof gypsum board may have cracks due to incomplete physical properties, weak fire resistance, high cost, and weak physical properties, resulting in structurally robust, improved fire protection and reinforcement. The development of fire-resistant gypsum board is urgently required.

Therefore, the present invention uses a ceramic fiber and silica powder which is excellent in fire resistance and reinforcing function in order to improve the above problems, structurally robust compared to the conventional, fire-resistant gypsum significantly improved fire and performance The purpose is to provide a board.

The present invention is a refractory gypsum board composed of a component containing hemihydrate gypsum, gypsum hardener and starch, comprising: 1 to 5 parts by weight of ceramic fibers, 5 to 15 parts by weight of silica, 60 to 95 parts by weight of gypsum, and 1 to 1 plaster of gypsum. It is characterized by the refractory gypsum board containing 7 weight part and 0.2-2 weight part of starches.

Referring to the present invention in more detail as follows.

The refractory gypsum board according to the present invention contains ceramic fiber, silica powder, gypsum, gypsum hardener, starch, fiber material, admixture, and each of these components will be described in more detail as follows.

Ceramic fiber used in the present invention forms a stable network structure in the refractory gypsum board to reduce the shrinkage of the gypsum board when the volume shrinkage due to the separation of the crystal water at high temperature as well as maintain the basic board structure at high temperature By maintaining the strength of the gypsum board to improve the fire resistance performance of the gypsum board, the ceramic fiber used in the present invention is a high temperature heat-resistant fiber with a safe use temperature of 1,000 ~ 1,400 ℃ preferably alumina-silica-based, alumina- Silica-zirconia type | system | group etc. are preferable, and the usage-amount is preferable to use 1-5 weight part. If the amount is less than 1 part by weight, the improvement of the fire resistance performance by the use of the ceramic fiber is lowered, and if it exceeds 5 parts by weight, it is not economical, it is difficult to dissociate the ceramic fiber into water during the manufacture of gypsum board, and the workability during the process There is a problem of deterioration.

In addition, since the silica powder used in the present invention is present in the gypsum board while the granular silica powder maintains a uniform dispersion state with the gypsum, the gypsum exhibits a local reverse stress when the volume shrinks due to the crystallization of the crystal at high temperature. By maintaining the strength of the gypsum board at high temperatures by reducing the pressure, not only improves the fire resistance performance of the gypsum board, but also serves to improve the mechanical properties of the gypsum board as a particle-reinforced composite.

The silica powder used in the present invention preferably has a water content of 0 to 30%, a SiO ₂ component of 85 to 100%, and a particle size of 80% or more to pass through 100 mesh. In order to improve the kneading property, it is preferable to screen and exclude so that agglomerates of 100 mm or more in diameter are not introduced. In addition, the amount of silica powder used in the fireproof gypsum board according to the present invention is preferably 5 to 15 parts by weight, and if the amount is less than 5 parts by weight, the effect of reducing the strength deterioration due to the use of the silica powder is low and the improvement of the fire resistance is not large. If it exceeds 15 parts by weight, there is no economy, and there is a problem of lowering the strength of the gypsum board.

Gypsum used in the present invention refers to _semi -hydrated gypsum (CaSO ₄ 1/2 / 2H ₂ O) calcined raw material gypsum at a temperature of 140 ~ 200 ℃, usually contains 5.5 ~ 7.5% of crystal water, the manufactured gypsum board High (CaSO ₄ · 2H ₂ O), usually 21 ± 3% of crystal water. The semi-hydrated gypsum has the property of being hardened by adding water, and acts to maintain the strength and physical properties of the gypsum board by combining with the ceramic fiber and silica powder, which are refractory materials according to the hardening, and the amount used is 60 to 95 parts by weight. It is preferable.

Gypsum hardening agent plays a role in promoting the hydration reaction when gypsum and water meet the hydration process, preferably, finely divided aluminum sulfate, sulphate sulfate and dihydrate gypsum itself. It is preferable to use a part.

Starch serves to bind the refractory material and gypsum well to the gypsum board base material, preferably acid treated corn starch, the amount is preferably 0.2 to 2 parts by weight.

In addition, the present invention may add 0.1 to 10 parts by weight of glass fiber to the refractory gypsum board in order to improve the strength of the gypsum board at room temperature or low temperature, the glass fiber used in the present invention is to cut long fibers It is preferable that fiber length is 6-15 mm as used or cut | disconnected previously. If the amount is less than 0.1 parts by weight, the effect of improving the strength of the gypsum board is low, and if it exceeds 10 parts by weight, there is a problem in that it is not economical and greatly decreases workability in the manufacture of gypsum board.

In addition, the present invention may be used in addition to the above components and various admixtures with the fiber material commonly used in the manufacture of gypsum board, the fiber material serves as a reinforcing auxiliary role separately from the glass fiber, preferably using pulp, admixture Denotes a blowing agent, a plaster retardant, a water reducing agent, a waterproofing agent and the like. The blowing agent in the admixture may mainly use an anionic surfactant. In addition, gypsum retardants and water-reducing agents slow the hardening of gypsum and reduce the amount of coma. In addition, other commonly used dispersants may be added. The waterproofing agent may be added to the refractory gypsum board according to the present invention in order to have the waterproofing performance as an additional function in addition to the fireproofing performance. The waterproofing solution mainly comprising a paraffin wax emulsion having a solid content of 45 ± 5% and a pH of 6-11 is added to the fireproof plaster board according to the present invention. These admixtures are mixed with water and air beforehand and foamed, and then added to a mixer during manufacture of gypsum board.

As mentioned above, gypsum boards and gypsum products have excellent heat resistance as building materials, which usually contain 40% of Calcium Sulfate and 21% of Calcium Sulfate. This is because it has a thermal stability below, and the crystallized water leaves at 45 to 200 ° C., resulting in a semi-hydrated gypsum having 5.5 to 7.5% of the crystal water. However, hemihydrate gypsum is completely decomposed into CaO and SO ₃ above 1,180 ° C through 3,2,1 anhydrous gypsum at 200 to 1180 ° C. In other words, gypsum board exists in the form of dihydrate gypsum, and as heat is applied, 21% of the crystal moisture is gradually transformed to water vapor state and is released. Eventually, it causes volume shrinkage by 21%. There is a problem. Therefore, the present invention uses the ceramic fiber and silica powder having excellent mechanical properties and high temperature properties, and the fibrous ceramic fiber and granular silica powder control the microstructure of the gypsum board at a high temperature, respectively. There is.

Although this invention is demonstrated in detail based on an Example, this invention is not limited to an Example.

Example 1

As shown in Table 1, 0.3 parts by weight of glass fiber, 3 parts by weight of ceramic fiber, 10 parts by weight of silica (water content of 0 to 30%) and 86.7 parts by weight of gypsum gypsum were transferred to a molding line, based on 100 parts by weight of the mixture. 90 parts by weight of water, 6 parts by weight of gypsum hardener and 0.2 parts by weight of starch were mixed to prepare a gypsum board according to a conventional manufacturing method.

Physical properties of the prepared gypsum board was measured by the method shown in Table 1, the results were as shown in Table 1 bending fracture load was 73.7kgf, flame resistance was 8 hours 51 minutes. These physical properties increased the bending failure load by more than 10kgf and the flame resistance performance was 8 hours compared to the conventional gypsum board (Comparative Example 1), which had no bending reinforcement load of 61.4kgf and flame resistance of 2 minutes 45 seconds. The result of the increase of more than 30 minutes shows that the fire resistance is excellent.

Example 2

As shown in Table 1, 0.3 parts by weight of glass fiber, 3 parts by weight of ceramic fiber, 10 parts by weight of silica (water content of 0 to 30%) and 81.7 parts by weight of hemihydrate gypsum were transferred to a molding line, based on 100 parts by weight of the mixture. 90 parts by weight of water, 6 parts by weight of gypsum hardener, 0.2 parts by weight of starch, and 5 parts by weight of a waterproofing solution were mixed to prepare a gypsum board according to a conventional manufacturing method.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 69.4kgf, and the flame resistance was 8 hours and 24 minutes. These physical properties can be seen that the excellent fire resistance performance compared to Comparative Example 1, it was confirmed that the water-absorbing performance was added as a total absorption rate of 4% as an additional function.

Example 3

As shown in Table 1, 3 parts by weight of ceramic fibers, 15 parts by weight of silica (0 to 30% of water content) and 76.7 parts by weight of gypsum gypsum were transferred to a molding line, and 90 parts by weight of water and gypsum based on 100 parts by weight of the mixture. 6 parts by weight of hardener and 0.2 parts by weight of starch were mixed to prepare a gypsum board according to a conventional manufacturing method.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 56.4kgf, and the flame resistance was 7 hours 41 minutes. These physical properties were found to be excellent in fire resistance compared to Comparative Example 1.

Comparative Example 1

As shown in Table 1, as a conventional gypsum board, 100 parts by weight of hemihydrate gypsum is moved to a molding line, and based on 100 parts by weight of this hemihydrate gypsum, 90 parts by weight of water, 6 parts by weight of a plaster hardener, and 0.2 parts by weight of starch are mixed. The gypsum board was manufactured by the method.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 61.4 kgf, and the flame resistance was 2 minutes 45 seconds.

Comparative Example 2

As shown in Table 1 above, 0.3 parts by weight of glass fiber and 99.7 parts by weight of gypsum gypsum were transferred to a molding line, and 90 parts by weight of water, 6 parts by weight of a plaster hardener, and 0.2 parts by weight of starch were mixed based on 100 parts by weight of the mixture. The gypsum board was manufactured by the method.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 67.2 kgf, and the flame resistance was 4 minutes 37 seconds. Flame resistance slightly increased in Comparative Example 1, but was still below the reference value of 8 minutes.

Comparative Example 3

As shown in Table 1, 0.3 parts by weight of glass fiber, 3 parts by weight of vermiculite, 10 parts by weight of clay and 86.7 parts by weight of semi-hydrated gypsum were transferred to a molding line, and 100 parts by weight of water and gypsum hardener 6 based on 100 parts by weight of the mixture. By weight, 0.2 parts by weight of starch was mixed to prepare a gypsum board in a conventional manner.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 65.9kgf, and the flame resistance was 38 minutes 22 seconds. Compared with Comparative Example 1, the strength was slightly increased and the flame resistance exceeded the standard value, but the fire resistance was still insufficient. In addition, the viscosity of the slurry mixed with gypsum was included in the formulation, the viscosity was increased and the workability due to the increased viscosity was confirmed that the amount of coma increased.

Comparative Example 4

As shown in Table 1 above, 0.3 parts by weight of glass fibers, 10 parts by weight of silica powder and 89.7 parts by weight of semi-hydrated gypsum were transferred to a molding line, and based on 100 parts by weight of the mixture, 90 parts by weight of water, 6 parts by weight of a plaster hardener, and starch 0.2 The gypsum board was manufactured by the conventional method by mixing the parts by weight.

The physical properties of the manufactured gypsum board were measured by the method shown in Table 1, and the results were as shown in Table 1, the bending fracture load was 60.3kgf, and the flame resistance was 45 minutes 52 seconds. Compared with Comparative Example 1, the flame resistance exceeded the reference value, but it was confirmed that the strength decreased.

As shown in Table 1, it was confirmed that the refractory gypsum boards of Examples 1 to 3 were much better in flame resistance than Comparative Examples 1 to 4.

As described above, in the present invention, in manufacturing a fireproof gypsum board having excellent flame resistance, unlike the conventional art, by appropriately blending ceramic fibers and silica powder, various physical properties are excellent and the flame resistance is significantly improved. .

In addition, when constructing a building with a fireproof gypsum board according to the present invention, the fireproof performance is superior to that of a conventional gypsum board, so that the thickness can be thinner or the number of layers of attachment can be reduced compared to the conventional gypsum board. There is.

Claims (5)

In the refractory gypsum board composed of a component containing hemihydrate gypsum, gypsum hardener and starch, 1 to 5 parts by weight of ceramic fiber, 5 to 15 parts by weight of silica, 60 to 95 parts by weight of gypsum and 1 to 7 parts by weight of gypsum hardener Refractory gypsum board comprising 0.2 to 2 parts by weight of starch. The refractory gypsum board according to claim 1, wherein 0.1 to 10 parts by weight of glass fiber is added to 100 parts by weight of the refractory gypsum board. The refractory gypsum board according to claim 1, wherein the ceramic fiber has a safe use temperature of 1000 to 1400 ° C. The refractory gypsum board according to claim 1 or 3, wherein the ceramic fiber is alumina-silica-based or alumina-silica-zirconia-based. The refractory gypsum board according to claim 1, wherein the silica powder has a water content of 0 to 30% and a particle size of 80 to 100% through 100 mesh.