KR101516981B1 - Mineral wool fiber composition having improved saline solubility and construction material containing the mineral wool fiber obtained therefrom - Google Patents

Abstract

The present invention relates to a mineral wool fiber composition having improved salt solubility and a building material containing mineral wool fibers obtained from the mineral wool fiber composition. More particularly, the present invention relates to a mineral wool fiber composition having improved heat resistance and fiber properties, To a building material such as a ceiling board containing a mineral wool fiber obtained from the mineral wool fiber composition and an inorganic insulation material which is environmentally friendly and inexpensively producible.

Description

TECHNICAL FIELD The present invention relates to a mineral wool fiber composition having improved salt solubility and a building material containing mineral wool fibers obtained from the mineral wool fiber composition.

The present invention relates to a mineral wool fiber composition having improved salt solubility and a building material containing mineral wool fibers obtained from the mineral wool fiber composition. More particularly, the present invention relates to a mineral wool fiber composition having improved heat resistance and fiber properties, To a building material such as a ceiling board containing a mineral wool fiber obtained from the mineral wool fiber composition and an inorganic insulation material which is environmentally friendly and inexpensively producible.

Mineral wool is a man-made mineral fiber (MMMF) product obtained by melting a silicate-based ore at a high temperature of 1,500 ~ 1,700 ° C and then using a high-speed spinning power of spinner. It is generally used as a mat, blanket, bulk or cover and has excellent heat insulation, fire retardancy and heat resistance and is used for various purposes such as heat insulation, insulation, sound absorption, soundproofing . It is also used as a ceiling board by wet-forming mineral wool fibers. When used in a ceiling panel, unlike mineral wool, which is generally used as a building / industrial interior material, it is directly exposed to the user. Therefore, human non-harmfulness of mineral wool fibers can be more important factor.

According to the International Agency for Research on Cancer (IARC) classification of carcinogenic substances, mineral wool fibers are classified as Group 3, not classifiable as to carcinogenicity to humans. However, if the broken fibers are absorbed and accumulated by the respiration into the lungs, there is a possibility of affecting the human body. Therefore, by increasing the solubility of the fibers in human body fluids (water containing a certain concentration of salt), it is possible to minimize the risk to the human body by allowing the accumulated fibers to be easily discharged outside the body. However, even if the saline solubility is improved, the basic properties of mineral wool should be maintained. That is, it is important that heat resistance should be provided so that the actual use temperature of the mineral wool can reach 700 to 800 ° C., the fiber must have a certain degree of fiber diameter, and the amount of the fine fiber shot should be minimized to improve the heat insulating performance Do.

Many researches have been carried out to find such optimal conditions. Among them, the decrease in the content of Al ₂ O _{3 in} the mineral wool fibers can improve the solubility of the fibers in the body fluids. Korean Patent Laid-Open Publication No. 2011-0097010 discloses a composition for preparing a bio-soluble ceramic fiber for a high temperature insulation material having a relatively high SiO ₂ content and a relatively low CaO and Al ₂ O ₃ content. This composition is excellent in salt solubility and exhibits excellent heat resistance in an ultra-high temperature environment of 1200 占 폚 or more, but has a high production cost and a relatively high content of microfibrillated particles and is therefore unsuitable for use in general industrial insulation materials and ceiling board production.

On the other hand, mineral wool (bale wool), which is mainly used for ceiling panels, is mainly made up of steel slag, which is a by-product of the steel industry. The iron slag is a by-product after iron is separated from iron ore. It has a characteristic that CaO content is about 40% higher and iron content is less than 1%. Also, because the Al ₂ O ₃ content of the iron slag is about 11% and Al ₂ O ₃ is essentially contained, it is difficult to design the above-mentioned low Al ₂ O ₃ composition in the mineral wool in which the iron slag is used as the main material. The existing low-alumina process has limitations in improving the salt solubility in the melting process, and is a difficult condition to realize in reality. Therefore, it is required to develop a mineral wool composition that is harmless to human body even if it is directly exposed to users when it is applied to general building materials such as a building insulation material and a ceiling board because Al ₂ O ₃ contains a certain part and exhibits improved salt solubility.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide a polyurethane foam which has heat resistance and fiber properties equivalent to those of existing products and is easily dissolved in body fluids, (Iron slag), which is a byproduct produced in the iron ore industry, can be produced as a main raw material. Therefore, it is possible to produce mineral wool fibers which are advantageous in terms of environmental friendliness and production cost And to provide a building material such as a ceiling board and an inorganic thermal insulation material containing the composition.

The present invention to solve the above technical problem is, SiO ₂ 32 ~ 48 _{wt%, Al 2 O 3 10 ~} 23 % by weight, CaO 23 ~ 40% by weight, MgO 2 ~ 8 wt%, and Na ₂ O and K ₂ O of from 1 to 4% by weight based on the total weight of the composition.

According to another aspect of the present invention, there is provided a mineral wool fiber characterized by being obtained by fiberizing the salt-soluble mineral wool fiber composition.

According to another aspect of the present invention, there is provided a building material including the mineral wool fiber, such as a ceiling board, an inorganic insulation material, and the like.

When the salt-soluble mineral wool composition according to the present invention is applied to a general building material, particularly a ceiling board, dust that may be generated during work such as repairing / replacing due to construction of a ceiling board or breakage / repair is sucked into the human body It is easily dissolved in body fluids and can be removed from the body. Further, the salt-soluble mineral wool composition of the present invention can be achieved by using iron slag, which is a by-product of the iron ore industry, as the main raw material, thus being environmentally friendly and advantageous in terms of production cost.

Hereinafter, the present invention will be described in detail.

Mesh formed of oxide SiO ₂ serves to form the basic structure of the mineral wool fibers. The composition of the present invention contains 32 to 48 wt%, preferably 39 to 44 wt% of SiO ₂ in 100 wt% of the total. If the content of SiO _{2 in the} composition is less than 32 wt%, the water resistance is lowered, and the fiber structure is likely to collapse substantially at the stage of manufacturing a wet building material (for example, a ceiling board). When the SiO ₂ content is more than 48 wt% And an increase in the amount of microfibrillated particles (shot).

The intermediate oxide, Al ₂ O ₃ , increases the viscosity of the glass melt near the liquidus line to control the crystallization of the glass and improve the water resistance of the fiber. The composition of the present invention contains 10 to 23% by weight, preferably 14 to 22% by weight, of Al ₂ O ₃ in 100% by weight of the whole. If the content of Al ₂ O _{3 in the} composition is less than 10% by weight, the water resistance of the composition is deteriorated. If the composition is more than 23% by weight, the salt solubility of mineral wool fibers may be decreased.

In one embodiment of the present invention, when no alumina source is used, the Al ₂ O ₃ content may be in the range of 13 to 15.5 wt%, and when a separate alumina source is used, the Al ₂ O ₃ content may be in the range of 20 to 23 wt% have.

CaO and MgO are alkaline earth metal oxides (RO) which play a role in improving salt solubility and have a positive effect on the fiberization, such as reducing the viscosity of the glass melt and improving the chemical durability. The effect of MgO on salt solubility can be said to be larger than that of CaO. The composition of the present invention contains 23 to 40% by weight of CaO and 2 to 8% by weight of MgO, preferably 25 to 36% by weight of CaO and 4 to 6% by weight of MgO in 100% by weight of the whole. If the content of the alkaline earth metal oxide is less than the lower limit, the melt viscosity may increase to increase the shot content or increase the fiber diameter. On the contrary, if the content exceeds the upper limit, the difference between the fiberization temperature and the crystallization temperature decreases There is a possibility that the crystallization progresses during the fiberization operation and the smooth fiberization can not be performed.

Na ₂ O and K ₂ O are alkaline metal oxides (R ₂ O), which act as a melting agent for smoothly progressing melting by generating non-crosslinked oxygen, and also improve salt solubility. The composition of the present invention comprises 1 to 4% by weight of the sum of Na ₂ O and K ₂ O in the total 100% by weight, preferably 1.5 to 3.5% by weight of the sum of Na ₂ O and K ₂ O. Na ₂ O and K ₂ O may each be included in the composition in an amount of 0 to 4 wt%, preferably 0.5 to 3.5 wt% of Na ₂ O and 0.5 to 3.5 wt% of K ₂ O, It is not. If the sum of Na ₂ O and K ₂ O in the composition is less than 1 wt%, the solubility of the salt is lowered, and if it exceeds 4 wt%, the water resistance of the fiber is lowered.

The total content of the modified oxides CaO, MgO, Na ₂ O and K ₂ O is preferably 30 to 50% by weight based on 100% by weight of the total composition in terms of improvement in salt solubility.

The salt-soluble mineral wool composition of the present invention may further contain other components such as iron oxide (FeO or Fe ₂ O ₃ ), TiO ₂ and the like in addition to the above-mentioned components, though not intentionally. In the case of iron oxide (FeO or Fe ₂ O ₃ ), 0 to 5% by weight may be included in 100% by weight of the total composition. In the case of TiO ₂ , 0 to 3% by weight may be included in 100% by weight of the composition.

According to one embodiment of the present invention, the composition of the present invention can be produced by using a byproduct slag (iron slag), which is a byproduct generated in the iron ore industry, as a main raw material. In this case, the content of iron oxide (FeO or Fe ₂ O ₃ ) in the composition is preferably 0 to 5 wt% (more preferably 0 to 3 wt%) by using not less than 70 wt% of the raw material, ).

The salt-soluble mineral wool composition according to the present invention can be prepared in the same manner as a conventional method for producing a mineral wool composition. For example, it is possible to melt by using the heat of combustion of cokes in Cupola, and it may be melted by electric resistance heat using an electric melting furnace using anisotropic graphite electrode. However, The present invention is not limited thereto.

There are various methods of making the molten mineral wool molten metal into a fiber, but the conventional method can also be applied. For example, a method of dropping a melt onto the surface of a spinner wheel in the form of a disk rotating at high speed, and simultaneously blowing strong wind around the spinner wheel, and making the melt to be long in a fiber shape by the centrifugal force, . However, this is not limited to the above method.

The salt-soluble mineral wool fiber of the present invention obtained as described above preferably has a dissolution rate constant of not less than 250 ng / cm 2 · hr (more preferably not less than 300 ng / cm 2 · hr) for a physiological saline solution having a pH of 4.5 ± 0.1 (For example, 300 to 450 ng / cm 2 · hr), the average fiber diameter is 7 μm or less (for example, 4-7 μm), the shot content after passing through the 35 mesh is 4 wt% Is not more than 3.5% by weight).

The salt-soluble mineral wool fiber of the present invention satisfying the above characteristics has heat resistance and fiber characteristics equivalent to those of conventional products and is excellent in salt solubility even if it is inhaled into human body. Therefore, it is easily dissolved in body fluids and discharged and removed from the body And can be suitably used for general building materials such as a ceiling board and an inorganic insulation material.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the scope of the present invention is not limited thereto.

Examples 1 to 7 and Comparative Examples 1 to 5

A mineral wool fiber composition was prepared by the ingredients and contents shown in Table 1 (Examples) and Table 2 (Comparative Example). The produced mineral wool fiber composition was melted in an electric furnace, dropped through a tapping hole having a diameter of about 50 mm at the bottom side of the melting furnace, and dropped into a fiberizer rotating at a high speed. Using a centrifugal force of a spinner Mineral wool fibers were produced by the method of producing fibers. The fibers listed in Table 1 and Table 2 were evaluated for the fibers produced in this manner.

[Table 1] (content of ingredients:% by weight)

[Table 2] (content of ingredients:% by weight)

According to the above Table 1, the dissolution rate constant (Kdis) for the fiber-treated fiber in the Examples was 250 ng / cm 2 · hr or more, and the salt solubility to the artificial body fluid was excellent. Also, it was confirmed that the heat shrinkage ratio has a heat resistance higher than an appropriate level.

According to the above Table 2, in Comparative Examples 1 and 2, the content of Al ₂ O ₃ was low and the salt solubility was relatively low. Al ₂ O ₃ is an intermediate oxide, and when it is not contained at an appropriate level, it becomes a main cause of deterioration of salt solubility. In particular, in the case of Comparative Example 2, the content of SiO ₂ was higher than the content of Al ₂ O ₃ , indicating that the fiber content and shot content were high. In Comparative Example 3, the SiO ₂ content was high and the viscosity was increased due to the increase of the SiO ₂ content. However, the molten metal was rapidly cooled during the falling of the molten steel, resulting in an increase in the fiber diameter and the shot content. Also, it is considered that the solubility is lowered due to the decrease of relative oxide content. In Comparative Example 4, the Al ₂ O ₃ content was as high as 25.4 wt%, and the solubility was drastically deteriorated. In Comparative Example 5, the content of Na ₂ O + K ₂ O was high and the solubility was low.

≪ Measurement of physical properties &

1. Dissolution rate constant (K _dis )

In order to evaluate the solubility of the fibers prepared in Examples and Comparative Examples in body fluids, the dissolution rate constants of artificial body fluids were determined in the following manner. The solubility of the glass fiber in the salt is evaluated on the basis of the solubility of the fiber in the artificial body fluid. The dissolution rate constant (Kdis) is calculated using the following Equation (1) Respectively.

&Quot; (1) "

_{K dis = [d o ρ (} 1 - M / M o) 0.5)] / 2t

d _o : initial average fiber diameter (탆), rho: initial density of fiber (g / cm ³ )

M _o : mass of initial fiber (mg), M: mass of fiber remaining (mg)

t: Experiment time (hr)

The content (g) of the composition component contained in 1 L of the artificial body fluid used for measuring the dissolution rate constant of the fiber is as follows.

The glass fibers of the Examples and Comparative Examples were placed between thin layers between a 0.2 μm polycarbonate membrane filter fixed with a plastic filter support (Air Monitoring Cassette), and the artificial body fluid was filtered between the filters to set the dissolution rate Respectively. During the experiment, the temperature of the artificial body fluid was adjusted to 37 ° C, the flow rate to 135 ml / day, and the pH was maintained at 4.5 ± 0.1 using HCl. In order to accurately measure the solubility of fibers occurring over a long period of time, artificial body fluids filtered at specific intervals (4, 7, 11, 14, 21 days) were inductively coupled plasma (ICP) Coupled Plasma Spectrometer) was used to analyze the dissolved ions, and the dissolution rate constant (K _dis ) was determined using the above-described equation (1).

2. Heat shrinkage factor

In order to measure the heat shrinkage of mineral wool fibers, fibers were prepared as pad type specimens and used in the experiment. First, 220 g of fiber was thoroughly dipped in a 0.2% starch solution, poured into a 300 * 300 mm mold, the spun fibers were leveled, the surface deviation was reduced, and the pad was drained through the bottom of the mold. The pad was sufficiently dried for 24 hours or more in an oven at 100 ° C. and cut into a size of 100 × 100 × 25 mm to prepare a test piece. Platinum pins were used to mark the measurement points. Then, using a vernier caliper, The pads were placed in a furnace heated to 1000 ° C., heated for 1 hour, and then cooled at room temperature. The distance between the measurement points of the cooled specimen was measured to compare the measurement results before and after the heat treatment, and the linear contraction ratio was calculated using the following Equation (2).

&Quot; (2) "

Heat linear shrinkage _{(%) = (l 0 -l} 1) / l 0 × 100

Where l ₀ is the initial distance (mm) between specimen marks, and l ₁ is the length (mm) between specimen marks after heating.

3. Shot Contents

In the process of fiber fibrillation, it is called "shot". Shot content was measured by the following method. After measuring the weight of the sieve, 50 g of the fiber was weighed and weighed. The fibers were torn into pieces and placed in a blender so that the shots inside the fibers did not fall off. After stirring for 30 seconds with a blender, the mixture was filtered through a 35 mesh sieve to continuously pass water through the sieve so that only the shot could remain. Finally, the remaining shots were dried in a 120 ° C dryer for about 3 hours and weighed. Shot contents were obtained using Equation (3) below.

&Quot; (3) "

Shot Contents (%) = w ₁ / w ₀ 100

Where w ₀ is the weight (g) of the shot containing fibers, and w ₁ is the weight (g) of the shot excluding the fibers.

4. Fiber diameter

The fiber diameter was measured using an optical microscope, and the measurement method was as follows. First, a small amount of fiber was placed on a slide glass, and a drop of the slide dispersion was dropped and mixed. Cover glass was covered and then dried at room temperature for about 6 hours to prepare a prepalat (sample). A total of five prepara- tats were prepared, and the measurement was started by adjusting the magnification to x200 through a microscope. Fibers were randomly selected to measure the fiber diameter, and fiber diameter was measured in 100 pieces of each of the preparats to ensure randomness. The final measured fiber diameter was recorded and averaged to obtain an average fiber diameter.

Claims (8)

32 to 48 wt% of SiO ₂ , 10 to 23 wt% of Al ₂ O ₃ , 23 to 40 wt% of CaO, 2 to 4.7 wt% of MgO, 1 to 4 wt% of Na ₂ O and K ₂ O, 3% < / RTI > by weight of a salt-soluble mineral wool fiber composition,
characterized in that the dissolution rate constant for an artificial body fluid having a pH of 4.5 ± 0.1 is 300 ng / cm 2 · hr or more, the average fiber diameter is 7 μm or less, and the shot content after passing through 35 mesh is 4%
Mineral wool fiber for construction materials. The mineral wool for construction material according to claim 1, characterized in that the total content of CaO, MgO, Na ₂ O and K ₂ O in the salt-soluble mineral wool fiber composition is 30 to 50 wt% fiber. The mineral wool fiber for building material according to claim 1, wherein the iron slag is used in an amount of 70 wt% or more of the raw material in the salt-soluble mineral wool fiber composition. A building material comprising the mineral wool fiber for construction material according to any one of claims 1 to 3. The building material according to claim 4, which is a ceiling board. The building material according to claim 4, characterized by being a heat insulating material. delete delete