KR930009344B1 - Manufacture of mineral fiber board - Google Patents

Abstract

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Description

Moisture resistant rockwool ceiling board

1 is a perspective view of a moisture resistant rockwool ceiling board according to the present invention.

2 is a cross-sectional view taken along the line A-A of FIG.

Figure 3 is an explanatory view showing a process of molding the pattern of rockwool ceiling plate according to the present invention.

Figure 4a is a cross-sectional view of a conventional directional wet rock surface ceiling plate, (b) is a cross-sectional view of the natural patterned semi-wet rock surface ceiling plate of the present invention.

5 is a perspective view of a molding die used in the present invention.

6 is a schematic view of a manufacturing apparatus for producing the ceiling plate material of the present invention.

7a, b, c or schematic diagram showing various operating positions of the surface smoothing roll of the manufacturing apparatus of the present invention for finishing the surface of the dried ceiling plate.

8 is a manufacturing process diagram of the present invention.

9 is a graph showing the drying temperature of the dryer and the curing temperature of the center of the specimen.

* Explanation of symbols for the main parts of the drawings

1: forming mold 2: conveyor belt

3: screw type dough 4: mixer

5: screw 6: extruder

7: thickness control means 8, 9: pattern molding machine

10 dryer 11 surface smoothing roll

The present invention relates to a rockwool ceiling plate, a manufacturing method and a manufacturing apparatus of the interior materials of the building, in particular by the semi-wet method to have an excellent moisture resistance to be used even in high temperature and humidity places such as indoor swimming pool, kitchen, washbasin The present invention relates to a moisture resistant rockwool top plate having excellent non-combustibility, light weight, heat insulation, sound absorption characteristics, and the like as a rockwool top plate.

In general, the sound absorption rate (NRC) in the physical properties of the rock wool ceiling plate depends on the pore characteristics of the material, so that the sound absorption incident on the material enters the pore velocity of the material, the more the sound absorption rate becomes better.

That is, in order to allow a lot of unnecessary sound into the material, there must be a lot of open holes on the surface of the ceiling material, and an appropriate density, that is, a pore property, must be formed so that a lot of the sound can disappear.

If the density is too high, the sound is blocked and reflected, resulting in high noise. If the density is too low, the sound is transmitted and transmitted to other places, and the intensity is lowered, resulting in problems in handling the product. Should be maintained. In addition, it is not only excellent flame retardancy enough to disturb the propagation of fire without generating harmful gases in the fire, but also directly visible to the eyes as a finishing material of the ceiling, the beauty of the surface is required. In addition, the resistance to moisture, that is, moisture resistance is also very important as a ceiling plate material. The place where a large amount of moisture occurs according to the hot and humid season or place in the summer season causes moisture absorption in indoor swimming pools, kitchens, washbasins, etc., resulting in deterioration of the appearance and properties of rockwool ceiling plates. As a specific example, color change due to surface condensation, warpage (SAG) due to moisture absorption, and the like become fatal defects as a ceiling plate material.

In the conventional method of manufacturing rockwool top plate material by wet method, the raw material is made into 2-5% slurry state and dehydrated to form wet plate, and it is cut and surface ground to the required standard through drying process. It was common to make the desired product by pattern pressing, and water repellent and other raw materials were added in the raw material mixing process as needed. However, the rock wool ceiling plate by the wet method has a disadvantage that the pattern is limited by artificially creating a needle hole or insect pattern after drying, the pattern is monotonous and thus the aesthetic appeal is low and the sound absorption rate is relatively low.

Related patents of rockwool ceiling boards with improved moisture resistance include Japanese Patent No. 87-27570, which uses 2-10% of phenol resin, melamine resin, and water-resistant PVA resin as a re-wetting binder. Sodium polycarbonate, potassium polyacrylate salt, alkali metal chloride of sodium silicate, etc. are added at the time of annealing using 3-20 wt%, which is gelled in water and can be fixed to the fixed part of the fiber, but white water There is a disadvantage in that the productivity is reduced due to less spillage, and above all, as the manufacturing method by the wet method, the pattern molding by generating the pattern after the primary drying is greatly limited, and as can be clearly seen in the following detailed description, the manufacturing method and the semi-wet manufacturing method of the present invention The way is quite different. In addition, the method presented in Japanese Patent No. 87-128978 is also a wet method, which is manufactured by mixing the wet plate to have a moisture content of 40-70% (drying standard). However, it is known that water absorption is increased by preventing migration of starch. As phosphorus starch, there is no choice but to expose the limit to moisture resistance, in particular to warpage (SAG).

In addition, Japanese Patent No. 87-78139 and the like are also limited to the method of manufacturing a wet rock surface ceiling plate. U.S. Patent Nos. 3243340, 4444594, and 3146516, etc., are also obtained by a wet method by a partial coating method for reducing warpage, such as 2 '× 4' manufactured by a semi-wet method as in the present invention. Even in sufficiently large dimensions, there is little bending property and, moreover, the property is different from the characteristic of having complete moisture resistance.

Although it will be described in detail later, the present invention is different from the fiber arrangement state of the rock wool ceiling plate material by the wet method and the fiber arrangement state by the semi-wetting method. It overcomes the problems and gives excellent moisture resistance and water resistance for the first time by the anti-wetting method, and provides the ceiling plate with excellent non-flammable, light-absorption, and excellent sound absorption.

An object of the present invention is to provide a ceiling plate produced by a semi-wet method. Another object of the present invention is to form a pattern by the pattern molding before drying the ceiling plate material which is easy to form the pattern and has a width and depth enough to feel a natural and sufficient three-dimensional feeling state To provide.

Yet another object of the present invention is to provide a ceiling plate material that can feel the excellent aesthetics because it is easy to mold the pattern by the pattern molder before drying and has a width and depth enough to feel a natural and sufficient three-dimensional feeling It is.

It is still another object of the present invention to provide a ceiling plate member having a porous sound absorbing characteristic due to a granular structure and having an excellent sound absorbing force having a width and depth of a pattern sufficient to have sound absorbing power.

Still another object of the present invention is to provide a ceiling plate member having a width and depth of a pattern sufficient to have an excellent sound absorbing power and a porous type by a granular structure, and thus having an excellent sound absorbing power.

Another object of the present invention is to provide a ceiling plate material having almost no bending property even in sufficiently large dimensions and having excellent moisture resistance.

It is still another object of the present invention to provide a ceiling plate having almost no bending property even in sufficiently large dimensions and having excellent moisture resistance.

The present invention is described in detail as follows.

A schematic description of the raw materials used in the present invention is as follows.

The overall blending ratio of the raw materials used to make the dough primarily by using a binder, water-resistant and powdery phenolic resins as a main ingredient, and inorganic fillers and other additives to granular rock wool having a constant particle size as a main material is expressed as a dry weight ratio. As follows.

TABLE 1

The granularity used is 73-76% of 2-5 mesh remaining rock, 2-5% of 5-6 mesh remaining rock, 2-5% of 6-7 mesh remaining rock, and 16-26% of remaining rock surface below 7 mesh. 2-18 mesh remaining rock wool 14-18%, 5-6 mesh remaining rock wool 8-12%, 6-7 mesh remaining rock wool 4-10%, less than 7 mesh remaining rock wool 55-70% Can be adjusted to use. In using the raw material rock wool particle size, the pattern forming state changes according to the kneading conditions and time, and the density is different. It is preferable to adjust the particle size of the granular rock surface of the final dough to be 1-3mm.

The raw material used was a powdered phenolic resin as a binder.

This is a phenol-formaldehyde resin containing a hardening agent of hexamethylenetetramine as a white or pale yellow fine powder. It is a thermosetting noblock type phenolic resin with excellent adhesiveness and strength, good releasability and excellent moisture resistance. The phenolic resin itself has a melting point of 80-90 ° C, a curing time (155 ° C) of 45-55 seconds, a water content of 0.8% or less, and a particle size of 100-300 mesh. The particle size of the resin is important, and if it is too thick, there is a problem in strength distribution because it is not evenly mixed, and if it is too fine, the resin moves in the direction of water movement due to the vapor pressure inside the plate during drying, which rises to the surface and consequently the surface is hard The interior will cause a decrease in strength. Therefore, care should be taken as granularity is an important issue.

Normally, when using a noblock phenolic resin, hexamine, which is a curing agent, is soluble in water, so it becomes thermoplastic like a resol type resin. Hardening does not dissolve in the solvent and does not melt even when heated. In addition to phenolic resins, waterborne binders such as corn starch, tapioca, and PVA alone or mixed use may cause problems under extreme conditions of water. Therefore, it is not recommended to use a mixture of water-soluble binders and phenolic resins. There may be many types of inorganic fillers used. That is, gypsum, dolomite, calcium carbonate, acidic whiteness, clays, and the like can be used, but a limited amount of organic fillers can be used for expressing strength while using a limited amount of organic binders. As described below, it is preferable to use clay having high compatibility and good dry strength when using guar gum as a thickener. In order to prevent severe dry shrinkage, it is recommended to use a proper amount of gypsum mixed.

The clay used in the present invention was used as the clay with the name "MS M-end di (Mississippi M & D, less than M & D quot;) calculated in the vicinity of the Mississippi River Basin Gypsum is the common half of gypsum (CaSO _4, 1 / 2H ₂ O) M & D clays have very low dry swelling properties, so the shrinkage is very low compared to other clays, and the bond strength of clays is very high at high temperatures. Normal clays do not show plastic bonds at 600-650 ℃, but M & D clays show plastic bonds, so the risk of destruction of the ceiling plate in the event of a fire is very small.

The main constituent mineral of M & D clay is kaolinite (Al ₂ O ₃ , 2SiO ₂ , 2H ₂ O), and the average particle diameter is 8.94 μm. The chemical composition is SiO ₂ : 62.3% Al ₂ O ₃ : 32.2% Fe ₂ O ₃ : 1.3% MgO: 0.9% CaO: 0.9% Na ₂ O: 0.3% K ₂ O: 0.7% TiO ₂ : 0.1%.

Physical properties include 5.9% loss of ignition, 1.1 times of swelling, PH 8.94, 6.02% of dry shrinkage, 40.08kgf / cm2 of compressive strength, 28.73Kgf / cm2 of bending strength. As an inorganic filler, M & D clay: half-hydrated gypsum can be used in the range of 2: 1-1: 2, which greatly reduces the shrinkage rate of the specimen during drying and exhibits self-firing bond even at 600-650 ℃ during fire. Interferes with fire propagation. Thickener is a very important to use as a viscosity control agent of the dough material for forming the desired pattern, but there are many natural and synthetic polymers, but in the present invention, stable and cold water soluble guar-gum was used. The structure is composed of every other D-mannose has D-galactose, that is, D-mannose: D-galactose = 2: 1, the molecular weight is about 200,000-300,000. A highly sensitive solution can be obtained, the stability of the dispersed particles is high and it is for cold water.

Because it is nonionic, it does not affect salts and shows compatibility over a wide range of electrolyte concentrations. When sensitive to boron, 1% boron solution is added dropwise to the guar-gum 1% solution to crosslink to form a gel to obtain a higher viscosity. It is stable even at relatively high temperatures, up to 90-95 ° C and does not cause the original viscosity change. Therefore, in the present invention, the borax 1% solution was used by adding about 0.4-1% to the 1% guar-gum solution.

Figure 6 shows a manufacturing apparatus for manufacturing the ceiling plate material of the present invention, the conveyor belt (2) for transporting the molding die 1 in close proximity to the ground is installed, and the screw-type dough (top) on one side of the conveyor belt ( A mixer 4 rotatably mounted and an extruder 6 rotatably mounted with a plurality of screws 5 below the outlet of the mixer, and the raw material thickness adjusting means adjacent to the outlet of the extruder. (7) is provided, and the first and second pattern molders (8), (9) dryers (10) and surface smoothing rolls (11) are installed in the rotational direction of the conveyor belt.

The method for manufacturing a moisture resistant rockwool top plate according to the present invention is described in the applicant's previously filed application No. 89-20490, but in order to aid the understanding of the present invention, the raw material treatment and manufacturing process are used here again. When described in detail with the drawings as follows.

As shown in FIG. 6, the granulated rock wool having the particle size adjusted is placed in the mixer 4, and the medium agent solution, the gelatinized starch, and the inorganic filler are added thereto. The raw material dough kneaded for 3-5 minutes by the screw-type dough sphere 3 rotatably mounted in the mixer is introduced into the extruder 6 in which the plurality of screws 5 are rotatably mounted. At this time, the extruder 6 installs screws 5 in 3-10 independent pipes to rotate the screws to push the raw materials to the feeder outlet, and the raw material dough is pushed out to the outlet of the raw material extruder 6 to the thickness of the raw material. The thickness is adjusted by the adjusting means 7 and supplied to the mold 1 on which the separating paper or aluminum foil is disposed. The frame filled with the raw material is then transferred to the right side of the drawing by the conveyor belt to remove the raw material slightly thicker than the frame by the primary pattern molder 8 and adjusted to the desired thickness by the secondary pattern molder 9. At the same time, a desired pattern is obtained. In order to prevent a pattern from being produced by the primary pattern molder 8, the angle is smaller than that of the secondary pattern molder. In general, the angle of the primary pattern molder is about 20-40 ° and The angle is between 30 and 60 degrees.

What is important here is that the pattern-formers perform a linear reciprocating motion. This reciprocating speed is directly related to the speed of the mold. When the speed of the mold is usually 2-10M / Min, the reciprocating speed of the patterned molders is about 50-300 times. In addition, the shape of the contact part of the raw material is closely related to the pattern molding, but various shapes can be used, but the angle α of the pattern forming machine, which is the secondary pattern molding machine, is 30-60 ° as shown in detail in the enlarged view. The contact area t of 2-4mm is helpful for pattern formation. When the angles of α and t are significantly different from each other, the pattern protrudes upward or the frequency of generation of the pattern is different, which makes the surface pattern undesirable. The patterned wet plate is generally smoothed, but some of the patterns may be protruded upwards, so that the wet plate is moved to the surface dryer 10 to dry the surface in the surface dryer and slightly by the surface smoothing roll 11. It is possible to obtain a flat wet plate by pressing only the protruding pattern, and to apply the product by drying and surface grinding or by applying the surface without grinding. As shown in FIG. 5, the mold used herein operates the pattern molders 8 and 9 so that the height of the front and rear partition walls A is at least 2 mm higher than the height of the partition walls B on both sides. By the flow of the surface of the dough is facilitated to facilitate the pattern molding as well as to increase the use efficiency of the dough. In addition, the surface smoothing operation in the dough mold, rather than the surface coating in the surface dryer (10) and the surface through the smoothing process by the roll (11) to open the surface (open hole) ) Is more present, which helps to improve sound absorption.

The reason for the excellent sound absorption of the object according to the present invention is that the overall cracks or openings are randomly generated on the plate surface as shown in the enlarged view of part B of FIG. 2, so that the sound is separated between the porous sound-absorbing characteristics of the rock surface and the cracks. When hit, it exhibits a resonator-type sound absorption characteristic in which sound energy is consumed as frictional heat in the vicinity of the resonance frequency, resulting in a higher sound absorption rate than conventional wet rock ceiling plates. The size of the surface pattern may vary slightly depending on the temperature of the raw dough, the viscosity, and the granularity of the granular rock surface. and c are also shown. In general, it is possible in position (b), but if it is slightly larger or smaller than the desired pattern, the pattern size of the final object can be adjusted within the same category by the positions (a) and (c). If the internal temperature of the dryer is too high during drying, the moisture drying speed on the surface will be high, but the viscosity of the dough will make it difficult to discharge moisture inside the raw material, resulting in poor drying or deterioration of the function of guar gum or resin. It is especially important to properly maintain the internal temperature of the.

Drying conditions in the present invention are as follows. For clarity, FIG. 9 shows the drying temperature of the dryer and the curing temperature program inside the specimen. If the wet plate is kept at 230 ℃ for 2 hours and 20 minutes, the internal temperature of the dryer drops to about 130 ℃ because of the water vapor during the first hour.Then, if the drying time is over 2 hours and 20 minutes, 200 When the temperature was restored, the internal moisture content of the wet plate was high, but browning of the external surface began to appear. If the dryer's set temperature is adjusted to 150 ℃ and kept for 2 hours and 40 minutes, the dryer's internal temperature is finally maintained at about 150 ℃ and the wet plate's internal temperature is maintained at about 70-75 ℃. The peak of the internal central temperature of the specimen is shown beyond this temperature range. At this time, the moisture content of the wet plate is about 7-10%, but until now hardening of the powdery phenolic resin has not been made. At this point, when the specimen is put into another dryer maintained at about 200 ° C., the specimen is completely dried and cured at the same time. The time required is about 30 minutes. When exiting the final dryer, the core temperature inside the specimen reaches about 160-170 ° C, resulting in complete curing. Thus, the cross-section of the finished state by smoothing the surface of the dried product or surface coating as it is is shown in Fig. 2, and the sound insulation is applied by attaching paper or aluminum foil to the back side before and after drying the raw material. -10% improvement

In this way, the surface of the rockwool top plate obtained by the manufacturing method of the present invention is a novel and natural enough to feel a three-dimensional appearance of the cracked state, so as to obtain an excellent aesthetic that can be used as a high-grade ceiling plate material. Randomly cracked pattern on the front of the plate has a sufficient depth as shown in the cross-sectional view of FIG. 2, but there is no abnormality in strength expression, and the inside thereof is delicate and irregular in shape, so that excellent sound absorption can be expected. In addition, the description of the resistance to warpage (SAG), that is, the moisture resistance characteristics, even in a sufficiently large dimension by the semi-wetting method will be described with reference to the following examples.

Example 1

This example is shown to compare the physical properties of the general wet rock surface ceiling plate with the physical properties of Example 3 of the present invention. The physical properties were measured while replacing the input amount of starch used as a binder in the mixing ratio of general wet rock surface top plate with liquid phenolic resin. Since the liquid phenolic resin is dispersed in water, the ratio of phenolic resin was adjusted by the amount of water remaining on the wet plate after dehydration, and 10% of the amount of phenol solids was added as a curing agent for curing the phenolic resin.

Drying conditions: The molded specimens were dried at a constant temperature in a hot air drier at 100 ° C., and then cured at 200 ° C. for 30 minutes for curing of the phenol resin, and then measured for physical properties.

[Properties]

TABLE 2

As can be seen in Table 2, when the liquid phenolic resin is used, the absorption rate is lowered from 200% to about 80% compared to the use of starch, but the strength of the body is sharply reduced. This is because the phenolic resin, which was dispersed in the substrate, is dried and hardened by moving to the surface of the substrate with moisture, but the surface becomes hard, but the inside loses the bonding strength and degrades the physical properties of the product. Therefore, it has been proved that general wet blending and the use of liquid phenolic resins are not suitable because they are largely inadequate in sound absorption and warpage (SAG) properties, which are the main points of the present invention.

Example 2

Example of the mixing of hot water soluble resin with phenol resin

According to the general wet method, the rock wool ceiling plate bonded by hardening of phenol using powdered phenolic resin showed excellent absorption rate and absorption strength, but the optimum ratio of each phenolic resin and hot water soluble resin (starch, etc.) was selected. In order to determine the physical properties as shown in the present invention, the physical properties were measured while changing the mixing ratio of the noblock-based phenolic resin and hot water soluble resin (starch).

Slurry Concentration: 4%

Specimen Size: 17 ^t × 2 '× 4'

Density: 350Kg / m ³

Drying conditions: After dehydration and molding, the specimen adjusted to a moisture content of 60% was dried in a constant temperature in a hot air dryer at 100 ° C., and then cured at 200 ° C. for 30 minutes to cure the phenol resin.

[Properties]

Table 3 shows the results of the physical properties that appear while changing the mixing ratio of the phenol resin and the hot water soluble resin (starch).

TABLE 3

As can be seen from the above table, in order to have a dry strength, absorption rate and absorption strength close to the target properties, when the phenol resin is added 6% or more and the amount of starch is added 5-7%, the above conditions can be satisfied, but the sound absorption rate and warpage In terms of characteristics, it is not suitable as mentioned in the text.

Example 3

Embodiment of the Invention

Mixing Method: After adding granular rock wool to the mixing dough, add filler and binder (gypsum, M & D clay, phenolic resin) and stir for 10 seconds to disperse the filler evenly within the granular rock surface, and then add solution (guar-gum, water). And stirred for 3 minutes.

[Molding conditions]

Specimen Size: 15 ^t × 2 '× 4'

Molding method: After supplying the dough to the mold and transporting it to the conveyor, the dough supplied to the mold by the primary pattern molder accumulated only a certain amount, and then dried by forming a crack pattern with the secondary pattern molder.

Drying condition: By the drying and curing temperature program shown in the text of the present invention

[Property Test]

[Bending test]

Test condition: 32.3 ℃ -90% RH-24hr

[result]

As shown in Example 3, it can be seen that according to the composition and the manufacturing method of the present invention, it is possible to manufacture a semi-wet rockwool ceiling plate having excellent drying and absorption strength and excellent sound absorption and moisture resistance.

Claims (4)

50-70 wt% of granulated rock wool, 25-35 wt% of inorganic filler, 4-15 wt% of powdered phenolic resin, and 0.5-3 wt% of organic additive. The method of claim 1, wherein the granular rock surface is 2-5 mesh residual rock surface 73-76%, 5-6 mesh residual rock surface 2-5%, 6-7 mesh residual rock surface 2-5%, 7 mesh or less residual rock surface 16- 2-25 mesh residual rock surface 14-18%, 5-6 mesh residual rock surface 8-12%, 6-7 mesh residual rock surface 4-10%, 55% to 7 mesh residual rock surface Moisture resistant rock wool ceiling material characterized in that the granular rock surface granularity in the final dough is 1-3mm. The moisture-resistant rockwool ceiling board according to claim 1, wherein the powdered phenol resin is a water-insoluble noblock type phenol resin containing hexamethylenetetramine. The moisture-resistant rockwool ceiling board according to claim 1 or 3, wherein the powdered phenol resin has a particle size of 100-300 mesh.