KR100788792B1 - A ceramic paper with epoxy binder, and Ceramic filter and Preparation method thereof using the same - Google Patents

Abstract

The present invention relates to a ceramic paper manufactured using a ceramic fiber as a main raw material, a ceramic filter using the same, and a method for manufacturing the same, wherein the ceramic paper has a fiber length of 0.1 to 10 mm and at least one selected from the group consisting of alumina and silica. Ceramic fiber containing; Organic fiber; And it is prepared from a slurry composition comprising an epoxy-based organic binder.

The ceramic paper of the present invention can increase the tensile strength and the wet tensile strength and increase the efficiency of the continuous paper manufacturing process using the water-soluble epoxy binder than the conventional acrylic binder.

Ceramic Paper, Epoxy Binder, Continuous Paper

Description

Ceramic paper using epoxy organic binder, ceramic filter using same and manufacturing method thereof {A ceramic paper with epoxy binder, and Ceramic filter and Preparation method using using same same}

1 is a perspective view schematically showing the structure of a ceramic filter according to the present invention.

Figure 2 is a graph showing a comparison of the wet-tensile strength (wet-tensile strength) for the ceramic green paper of 1 to 8 and Comparative Examples 1 to 4 in the practice of the present invention.

<Description of the symbols for the main parts of the drawings>

10: ceramic plate paper 20: ceramic corrugated paper

The present invention relates to a ceramic paper, a ceramic filter using the same, and a method for manufacturing the same. More particularly, in the manufacture of ceramic paper, an epoxy paper-based organic binder is used, and a ceramic paper having excellent handling strength, and a ceramic filter manufactured using the same, It relates to a manufacturing method.

Since the late 1970s, a diesel particulate filter (DPF) has been proposed and studied as a device for filtering particulate matter from diesel engines. The DPF can be broadly classified into honeycomb monolith filters, ceramic fiber filters, and metal filters. Of these, honeycomb monolith filters are vulnerable to high temperature thermal shock and have a short lifespan. In addition, metal filters have advantages in price and ease of fabrication, but have weak disadvantages in heat resistance and corrosion resistance. Accordingly, studies on nonwoven paper type filters made of ceramic fibers have been actively conducted in recent years.

In order to use the nonwoven paper made of ceramic fiber as a filter, the wave form is formed in the green paper state through wave form, and the surface area is increased in a single volume. However, in the case of ceramic paper composed only of ceramic fibers, since the paper itself has a small tensile force and a short fiber length, organic fibers such as cellulose fiber, nylon, kevlar (trademark), and various organic chemicals may be used to make continuous paper. It should be used to have tensile force. In addition to the process of making continuous paper, the tensile strength of the organic paper and various binders other than the ceramic fiber is required in the process of corrugating the ceramic paper.

Meanwhile, in WO 03/004438, a ceramic paper and a filter were manufactured by using a thermoplastic acrylic latex binder in a slurry made of a combination of an organic fiber including a ceramic fiber and a cellulose fiber.

However, conventionally manufactured ceramic paper contains acrylic binder as 2 to 10% as a binder and exists in the ceramic paper, and in addition to the binder which affects the handling strength (wet tensile strength) of the paper, the ceramic paper is dehydrated in water which is dehydrated during the paper manufacturing process. It caused a problem of contamination coming out. In addition, the binder containing the hydrophobic property is included in excess, so that there is a disadvantage that a penetrating solvent should be used during the subsequent immersion of the aqueous inorganic binder. In addition, the organic components present in the ceramic filter are burned away in the process of firing the inorganic binder after coating, whereby defects in the structure or local pores may be caused by the flying organic components.

In order to solve the problems in the prior art as described above, an object of the present invention is to provide a ceramic paper having hydrophilicity and equivalent or better handling strength with the use of a minimum amount of organic binder.

Another object of the present invention is to provide a ceramic filter comprising the ceramic paper and a method of manufacturing the same.

In order to achieve the above object, the present invention has a fiber length of 0.1 to 10mm, ceramic fiber comprising at least one selected from the group consisting of alumina and silica; Organic fiber; And it provides a ceramic paper prepared from a slurry composition comprising an epoxy-based organic binder.

The present invention also provides a ceramic filter having a honeycomb structure, which is made of ceramic paper having the above configuration that is corrugated.

The present invention also relates to (a) preparing a ceramic paper using a slurry solution of a ceramic fiber, an organic fiber, and an organic binder having the above-described structure and drying it; (b) corrugating and winding the dried ceramic paper to prepare a ceramic filter having a honeycomb structure, and (c) coating the ceramic filter with an inorganic binder solution; And (d) provides a method for producing a ceramic filter comprising the step of drying and firing the ceramic filter coated with the inorganic binder solution.

Hereinafter, the present invention will be described in more detail.

The present invention is to prepare a ceramic green paper by using a slurry solution of a ceramic fiber, an organic fiber, and an organic binder containing alumina or silica of 0.1 to 1mm, using an organic binder instead of an epoxy-based organic binder in the organic binder The present invention provides a ceramic paper having excellent wet tensile strength suitable for molding and handling strength capable of producing continuous paper, and a ceramic filter that can be used even at a high temperature by using the same.

The ceramic green paper used in the manufacture of the ceramic filter in the present invention can be prepared from a slurry solution comprising a ceramic fiber, an organic fiber and a small amount of organic binder.

The content of the ceramic fiber in the slurry solution is 50-80% by weight, more preferably 70-80% by weight based on the total solids of the slurry. When the content of the ceramic fiber is less than 50% by weight, it may adversely affect the strength and pore characteristics after firing. When the content of the ceramic fiber exceeds 80% by weight, the amount of the organic fiber and the organic binder is too small so that the tensile strength may drop during the wave formation step. There is.

The ceramic fiber is made of a material that can withstand about 1200 degrees or more, and uses at least one of alumina or silica, such as alumina and alumina silicate. For example, ceramic fibers use such as alumina, alumina silicate, alumina borosilicate, mullite, and the like. The ceramic fiber has a diameter of 1-20 microns, more preferably 2-7 microns in diameter, and preferably has a length of 0.1-10 mm.

The organic fiber may be selected from the group consisting of cellulose fibers, natural fibers such as hemp, nylon, rayon, polyester, polypropylene, polyethylene, aramid, synthetic fibers such as acrylic fibers, and mixtures thereof. Specific examples of the aramid fiber is Kevlar fiber manufactured by DuPont. The content of the organic fiber may be used in 5 to 50 parts by weight based on 100 parts by weight of the ceramic fiber in the slurry.

In addition, the present invention uses a smaller amount of the organic binder than the conventional one, and uses an epoxy organic binder instead of an acrylic binder.

The epoxy-based organic binder may be used a conventional epoxy resin, and the kind is not particularly limited, for example, those having a molecular weight of 4000 to 6000 can be used.

In the present invention, the content of the organic binder system is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the ceramic fiber, and if the content is less than 0.1 parts by weight, there is a problem in that a bond between the fibers is not formed, The properties of the green paper are not greatly improved, there is a problem that the waste water increases and sticks during molding.

In the present invention, a polyalkylene oxide polymer, a phenol enhancer, or the like may be used as necessary. The polyalkylene oxide polymer has a molecular weight of 100,000 to 6,000,000, and preferably has a molecular weight of 5,000,000 or more.

The phenolic enhancers include phenol-formaldehyde resins, tannin extracts, naphthol-formaldehyde condensates, poly (para-vinyl phenols), as well as those enhancers substituted with functional groups such as carboxylates, sulfonates, and phosphonates, wood The components of the tissue may be selected from the group consisting of lignin material, which is eluted during the pulping process, a mixture of the enhancer and lignin.

In addition, the slurry solution may include water, and the amount of water used in the slurry solution is not critical, and may be sufficient to keep the entire process smoothly. The present invention can remove excess water through a vacuum pump connected to the papermaking apparatus and remove excess water remaining through the press to smoothly remove water in the process.

In addition, in the slurry solution of the present invention, in order to improve adhesion of the organic binder to the ceramic fiber or the organic fiber, a conventional pH adjusting agent may be further added. The pH adjusting agent may be used without particular limitation as long as it is commonly used in the art, for example, by using alum (aluminum sulfate), it is possible to maintain the pH of the slurry solution between 5.5-6.5.

The manufacturing method of the ceramic green paper of this invention can use the papermaking method well known in the art normally, The method is not specifically limited. In one preferred embodiment, the ceramic fibers and the organic fibers are mixed to disperse the fibers, and the organic binder system having the above-described configuration is mixed to make agglomeration of the fibers, and then dried to prepare ceramic green paper. can do.

On the other hand, the present invention provides a ceramic filter by corrugating and winding the ceramic green paper. 1 is a perspective view schematically showing the structure of a ceramic filter of the present invention. In FIG. 1, reference numeral 10 denotes a ceramic plate paper, and 20 denotes a ceramic corrugated paper.

At this time, the ceramic plate-shaped paper used in the ceramic filter according to the present invention is not particularly limited as long as it is commonly used in the art (however, it is preferable that the plate-shaped paper and the corrugated paper should use only the same ceramic green paper), manufactured above Ceramic green paper can be used as it is.

The method for producing a ceramic filter of the present invention comprises: (a) preparing a ceramic paper using a slurry solution of 0.1 to 1 mm ceramic fiber, organic fiber and organic binder, followed by first drying; (b) corrugating the dried ceramic paper and (c) winding the ceramic paper in the above state and coating it with an inorganic binder solution; And (d) drying and firing the ceramic paper coated with the inorganic binder solution, thereby preparing a ceramic filter usable at high temperature.

The inorganic binder is not limited to any kind and can be used as long as it is used in the manufacture of a ceramic filter, for example, an inorganic colloidal solution selected from the group consisting of alumina sol, silica sol, and clay dispersion solution. , Aluminum phosphate solution, or mixtures thereof can be used.

The aluminum phosphate solution is used to increase the temperature and structural stability of the ceramic green paper filter structure. The aluminum phosphate solution is prepared by mixing aluminum hydroxide and phosphoric acid, and the P / Al atomic ratio in the solution may be 3 to 50. At this time, if the P / Al atomic ratio is less than 3, there is a concern that the solubility of alumina is very small and the formation of aluminum phosphate may not be smooth. If the P / Al ratio is higher than 50, phosphoric acid is excessive, so that the concentration of alumina is low so that the coating property is low and the surface of the fiber This damage can weaken the strength. The phosphoric acid serves to carbonize the organic fiber at a low temperature during firing, thereby preventing the organic fiber from burning and flying away.

In addition, if necessary, the surface may be first coated with alumina oxide powder before coating with aluminum phosphate.

In the present invention, the process of coating the ceramic green paper with the aluminum phosphate solution is not particularly limited, and may be performed, for example, by impregnation or spraying. The aluminum phosphate solution may further include a mixed solvent of water and a penetration solvent. Ethanol, isopropyl alcohol, etc. may be used as the penetration solvent, and the content of the penetration solvent may be used in an amount of 1 to 30 wt% based on water. If the content of the penetrating solvent is less than 1% by weight, the role is not smooth, and if it exceeds 30% by weight may cause the precipitation of aluminum phosphate. In addition, the content of aluminum phosphate in the total aluminum phosphate solution may be 1 to 80% by weight based on solids, and if it is less than 1% by weight, it must be repeated several times to coat the required amount, and exceeds 80% by weight. If there is an excessive amount of aluminum phosphate remains between the pores, the pore reduction phenomenon may appear and the impact resistance of the paper may be reduced.

In addition, the firing step can be carried out in a vacuum, inert gas or air, the firing temperature is preferably 800 ~ 1,100 ℃. When the firing temperature is less than 800 ° C, the organic component is not completely removed. When the firing temperature is above 1,100 ° C, the aluminum phosphate may be deformed, resulting in a decrease in strength.

Through the firing process, the organic fibers are carbonized to form pores, and the aluminum phosphate hollow fibers in the ceramic filter have two phases, Al (PO ₃ ) ₃ (aluminum metaphosphate) and AlPO ₄ (aluminum orthophosphate). It is believed to exist in mixed form.

On the other hand, the ceramic filter according to the present invention after the step of corrugating the ceramic green paper as described above, to produce a honeycomb form by bonding the corrugated ceramic waveform paper and the ceramic plate-shaped paper, the aluminum phosphate solution coating The process is preferably performed after manufacturing the ceramic filter of the honeycomb type. The waveform may be performed by using a waveform device commonly used in the art, for example, the drum of the waveform device that can be used in the present invention is each of the length of the valley and pitch of 3mm, It is desirable that the surface temperature and paper feed rate be controlled.

The ceramic filter having the honeycomb structure of the present invention thus obtained can be used as an exhaust gas filter to effectively remove particles contained in diesel exhaust gas. In addition, the ceramic filter of the present invention can also be used as a dust removal filter in power plants, chemical plants, cement plants.

Hereinafter, preferred examples and comparative examples of the present invention are described. However, the following examples are only one preferred embodiment of the present invention and the present invention is not limited to the following examples.

EXAMPLE

Example  1 to 4

2.16 g of alumina-silica fiber having an average length of 500 micrometers, 0.36 g of cellulose fiber, and 0.36 g of Kevlar fiber were added to 2000 ml of water, and vigorously stirred and dispersed using a high speed dissociator. After the fibers were well dispersed, the epoxy resin diluted to 0.5% was added at about 4 wt%, 2 wt%, 0.3 wt%, and 0.1 wt% of the total weight, respectively, and mixed well to achieve coagulation of the fibers (Table 1 Reference). After the stirring was continued gently so that the above components were mixed evenly, a ceramic green paper having a diameter of 16 cm and a thickness of 650 to 750 μm was prepared using a circular paper machine. The prepared circular paper was completely dried in a drying oven at 100 ℃.

[Table 1] (Unit: weight%)

Fiber Binder (Epoxy) pulp Kevlar Example 1 72% 4% 12% 12% 2.16 g 24 g (0.5 wt%) 0.36 g 0.36 g Example 2 74% 2% 12% 12% 2.16 g 12 g (0.5 wt%) 0.36 g 0.36 g Example 3 75.7% 0.3% 12% 12% 2.16 g 1.8 g (0.5 wt%) 0.36 g 0.36 g Example 4 75.9% 0.1% 12% 12% 2.16 g 0.6 g (0.5 wt%) 0.36 g 0.36 g

Example  5 to 8

2.16 g of alumina-silica fiber having an average length of 500 micrometers, 0.63 g of cellulose fiber, and 0.09 g of Kevlar fiber were added to 2000 ml of water, and vigorously stirred and dispersed using a high speed dissociator. After the fibers were well dispersed, the epoxy binder was added at 4 wt%, 2 wt%, 0.3 wt%, and 0.1 wt% of the total fiber weight, respectively, so that the fibers were aggregated (see Table 2). After the stirring was continued gently so that the above components were evenly mixed, a ceramic paper having a diameter of 16 cm and a thickness of 650 to 750 μm was prepared using a circular paper machine. The prepared circular paper was completely dried in a drying oven at 100 ℃.

[Table 2] (Unit: wt%)

Fiber Binder (Epoxy) pulp Kevlar Example 5 72% 4% 21% 3% 2.16 g 24 g (0.5 wt%) 0.63 g 0.09g Example 6 72% 2% 21% 3% 2.16 g 12 g (0.5 wt%) 0.63 g 0.09g Example 7 72% 0.3% 21% 3% 2.16 g 1.8 g (0.5 wt%) 0.63 g 0.09g Example 8 72% 0.1% 21% 3% 2.16 g 0.6 g (0.5 wt%) 0.63 g 0.09g

Comparative example  1 to 4

2.16 g of alumina-silica fiber having an average length of 500 micrometers, 0.36 g of cellulose fiber, and 0.36 g of Kevlar fiber were added to 2000 ml of water, and vigorously stirred and dispersed using a high speed dissociator. After the fibers were well dispersed, the acrylic emulsion binder was added to 4%, 2%, 0.3%, and 0.1% by weight of the total fiber weight, and the aluminum sulfate solution was sufficiently added to bring the pH to 5-6. . After the stirring was continued gently so that the above components were evenly mixed, ceramic green paper having a diameter of 16 cm and a thickness of 650 to 750 μm was prepared using a circular paper machine. The prepared circular paper was completely dried in a drying oven at 100 degrees.

TABLE 3

Fiber Binder (acrylic) pulp Kevlar Comparative Example 1 72% 4% 12% 12% 2.16 g 0.24 g (50 wt%) 0.36 g 0.36 g Comparative Example 2 74% 2% 12% 12% 2.16 g 0.12 g (50 wt%) 0.36 g 0.36 g Comparative Example 3 75.7% 0.3% 12% 12% 2.16 g 0.018 g (50 wt%) 0.36 g 0.36 g Comparative Example 4 75.9% 0.1% 12% 12% 2.16 g 0.006 g (50 wt%) 0.36 g 0.36 g

Wet tensile strength  Measure

For the ceramic green paper of Examples 1 to 8 and Comparative Examples 1 to 4 using a testrometric UTM (univesal testing machine M350-5CX) cut into a sample size width X length (1cm X 4cm) and sufficiently wetted with water and then load cell (load cell) Wet tensile strength was measured in 5kgf, the results are shown in Table 4 and FIG.

TABLE 4

Wet tensile strength (Force @ Peak, gf) Comparative Example 1-4 Example 1-4 Example 5-8 0.1 wt% binder 9.91 44.04 71.06 12.88 37 49.27 10.32 44.94 62.22 45.1 57.77 42.95 54.06 53.77 Average 11.0367 42.806 58.19167 0.3 wt% binder 10.95 49.3 119.76 9.95 55.15 135.62 7.32 71.47 86.39 10.91 60.08 125.62 9.7 43.54 98.4 10.2 66 Average 9.838333 57.59 113.158 Binder 2% by weight 11.79 71.73 113.29 8.64 85.36 143.44 7.94 75.26 142.63 9.23 84.65 5.57 76.32 Average 8.634 78.664 133.12 4 wt% binder 10.39 57.31 151.98 8.88 60.31 140.47 9 59.43 146.1 12.89 54.02 139.6 19.18 62.25 168.28 Average 12.068 58.664 149.286

Example  9

The same procedure as in Example 1 was conducted except that no Kevlar fiber was used.

Comparative example  5

The same procedure as in Comparative Example 1 was conducted except that no Kevlar fiber was used.

Wet tensile strength  Measure

The wet tensile strength of the ceramic green papers of Example 9 and Comparative Example 5 was measured in the same manner as described above, and the results are shown in Table 5 below.

TABLE 5

Wet tensile strength (Force @ Peak, gf) Comparative Example 5 Example 9 0.1 wt% binder 47.2 69.35 47.23 58.83 50.01 71.66 49.04 63.75 50.7 62.16 Average 48.836 65.15 0.3 wt% binder 64.49 167.38 68.04 160.55 43.85 181.42 77.26 169.16 70.22 157.87 Average 64.77 167.276 Binder 2% by weight 75.66 224.15 73.89 250.33 73.57 226.21 52.86 251.52 81.33 228.22 Average 71.46 236.086 4 wt% binder 80.89 221.33 86.23 221.68 84.98 221.12 81.67 238.76 71.6 253.98 Average 81.07 231.374

Example  10 to 13 (inorganic: organic (pulp + Kevlar ) = 3: 1)

Manufacture of Ceramic Paper

2.16 g of alumina-silica fiber having an average length of 500 micrometers, 0.63 g of cellulose fiber, and 0.09 g of Kevlar fiber were added to 2000 ml of water, and vigorously stirred and dispersed using a high speed dissociator. After the fibers were well dispersed, the epoxy resin diluted to 0.5% was added at about 4%, 2%, 0.3%, and 0.1% by weight of the total weight, respectively, and mixed well so that the fibers were aggregated (Table 6). Reference). Subsequently, polyethylene oxide diluted to 0.1% was added at 0.1% by weight of the total fiber weight to allow the fiber to aggregate. After the stirring was continued gently so that the above components were mixed evenly, a ceramic green paper having a diameter of 16 cm and a thickness of 650 to 750 μm was prepared using a circular paper machine. The prepared circular paper was completely dried in a drying oven at 100 ℃.

TABLE 6

Fiber Binder (Epoxy) pulp Kevlar PEO Example 10 72% 4% 21% 3% 0.1% 2.16 g 24 g (0.5 wt%) 0.36 g 0.36 g 3 g Example 11 74% 2% 21% 3% 0.1% 2.16 g 12 g (0.5 wt%) 0.36 g 0.36 g 3 g Example 12 75.7% 0.3% 21% 3% 0.1% 2.16 g 1.8 g (0.5 wt%) 0.36 g 0.36 g 3 g Example 13 75.9% 0.1% 21% 3% 0.1% 2.16 g 0.6 g (0.5 wt%) 0.36 g 0.36 g 3 g

Example  14 to 17

In preparing the ceramic green paper, the same method as in Example 10 was carried out, except that 0.2% of the phenol-based strengthening agent diluted to 2% was added to the total weight (see Table 7).

TABLE 7

Fiber Binder (Epoxy) pulp Kevlar PEO Pulmonary system Example 14 72% 4% 21% 3% 0.1% 0.2% 2.16 g 24 g (0.5 wt%) 0.36 g 0.36 g 3 g 0.3 g Example 15 74% 2% 21% 3% 0.1% 0.2% 2.16 g 12 g (0.5 wt%) 0.36 g 0.36 g 3 g 0.3 g Example 16 75.7% 0.3% 21% 3% 0.1% 0.2% 2.16 g 1.8g (0.5wt%) 0.36 g 0.36 g 3 g 0.3 g Example 17 75.9% 0.1% 21% 3% 0.1% 0.2% 2.16 g 0.6g (0.5wt%) 0.36 g 0.36 g 3 g 0.3 g

Wet tensile strength  Measure

Wet tensile strength was measured in the same manner as above for the ceramic green paper of Example 10-17, and the results are shown in Table 8 below.

TABLE 8

Wet tensile strength (Force @ Peak, gf) Ceramic Fiber: Organic Fiber (Cellulose + Kevlar) = 3: 1 + PEO Ceramic Fiber: Organic Fiber (Cellulose + Kevlar) = 3: 1 + PEO + Phenolic Enhancer Example 10 223.81 Example 14 294.37 233.37 313.89 220.74 285.46 237.69 297.69 249.92 320.68 Average 233.11 Average 302.42 Example 11 254.42 Example 15 221.43 277.7 204.1 227.34 221.65 259.37 191.18 258.33 192.25 Average 255.43 Average 206.12 Example 12 175.5 Example 16 210.98 188.17 231.44 188.45 232.25 185.67 234.38 185.54 224.81 Average 184.67 Average 226.77 Example 13 109.45 Example 17 85.9 109.54 104.95 107.39 117.86 109.92 120.08 101.35 105.88 Average 107.53 Average 106.93

Example  18

A filter was manufactured using the same ceramic paper as in Example 1, except that the wound ceramic filter was first and second coated using an inorganic binder as described below.

(Primary inorganic coating)

Alumina oxide powder having a size of 50 nm was prepared by mixing with water and isopropyl alcohol to have a concentration of 5%, 10% and 20%, respectively. The prepared ceramic green paper was immersed in the prepared alumina sol solution, coated, dried at 100 ° C. and finally heat treated at 1,100 ° C.

(Secondary inorganic coating)

Inorganic coating was performed on the heat-treated ceramic paper by using aluminum phosphate solution.

Aluminum phosphate was mixed with Al (OH) ₃ (manufactured by Aldrich) and H ₃ PO ₄ (85%, made by Junsei), quantitatively mixed so that the atomic ratio of P / Al was 23, and stirred while raising the temperature to 150 ° C. The Al (OH) ₃ powder was dissolved in phosphoric acid, thereby producing a high viscosity and clear solution.

In the aluminum phosphate solution for coating, the aluminum phosphate solution prepared above was dissolved in a 3: 1 mixed solvent of water and isopropyl alcohol to prepare a 20% aluminum phosphate solution. The first coated ceramic paper was dip-coated and dried at 110 ° C., and then fired at 800 ° C. under atmospheric conditions.

The load strength, average pore size and air permeability were measured using the finally obtained ceramic paper.

Example  19 to 27

A ceramic green paper was prepared in the same manner as in Example 18, except that the composition of the alumina sol of the primary coating solution and the ratio of P / Al of the secondary coating solution were changed as shown in Table 5 below. 9)

TABLE 9

Example Al ₂ O ₃ sol concentration AlPO concentration Peak load MFP Permeability 19 5% 23 176 28.7 15 20 5% 30 183 31.3 16 21 5% 35 171 34 17.3 22 10% 23 329 32.9 8 23 10% 30 385 21.1 8.8 24 10% 35 343 28.3 9.8 25 20% 23 300 33.8 10 26 20% 30 358 34.1 6.8 27 20% 35 371 30.9 4

Comparative example  6

The ceramic green paper of Example 1 was treated using the primary and secondary coating solutions prepared as follows.

 (Primary inorganic coating)

Bentonite clay powder having a size of 40-70 mm was mixed with water and isopropyl alcohol to prepare 2 wt% and 4 wt%, respectively. The ceramic green paper was immersed in the prepared clay powder solution, coated, dried at 100 ° C, and finally heat-treated at 1100 ° C.

(Secondary inorganic coating)

Inorganic coating was performed on the heat-treated ceramic paper by using aluminum phosphate solution.

Aluminum phosphate is mixed with Al (OH) ₃ and H ₃ PO ₄ to have a P / Al ratio of 23, and stirred while raising the temperature to 150 ° C. As a result, Al (OH) ₃ powder is dissolved in phosphoric acid. It was prepared to produce.

The aluminum phosphate solution for coating was dissolved in aluminum phosphate in a mixed solvent of water and isopropyl alcohol (3: 1) to synthesize a 20% solution. The first coated ceramic paper was dip-coated and dried at 110 ° C., and then fired at 800 ° C. under atmospheric conditions.

Finally, the obtained ceramic paper showed the strength of 61g load strength.

Comparative example  7

The ceramic green paper obtained in Example 1 was coated using only aluminum phosphate solution as a coating solution and heat-treated at 800 ° C. The strength showed 87g load strength value.

As described above, in the present invention, when the ceramic paper is manufactured by the wet paper manufacturing method, the wet tensile strength can be remarkably improved than the conventional acrylic binder by using a water-soluble epoxy binder instead of the conventional acrylic binder. Can be provided efficiently.

Claims (10)

A fiber length of 0.1 to 10 mm and comprising at least one member selected from the group consisting of alumina and silica; Organic fiber; And an epoxy organic binder having a molecular weight of 4000 to 6000, The content of the epoxy-based organic binder is a ceramic paper prepared from a slurry composition comprising 0.1 to 10 parts by weight with respect to 100 parts by weight of the ceramic fiber. The ceramic paper of claim 1, wherein the ceramic paper further comprises a polyalkylene oxide polymer or a phenolic enhancer. The ceramic paper according to claim 1, wherein the ceramic fiber is selected from one or more selected from the group consisting of alumina, aluminosilicate, alumino boro silicate and mullite, and comprises 50 to 80 wt% based on the total solids of the slurry. The method of claim 1, wherein the organic fiber is selected from the group consisting of cellulose fiber, hemp, nylon, rayon, polyester, polypropylene, polyethylene, aramid, acrylic fiber and mixtures thereof, the organic fiber content of the ceramic fiber 5 to 50 parts by weight of ceramic paper, based on 100 parts by weight. A ceramic filter having a honeycomb structure, which is made of a corrugated ceramic paper according to any one of claims 1 to 4 and a ceramic plate-shaped paper. The ceramic filter of claim 6, wherein the ceramic plate paper is made of the same material as the corrugated ceramic paper. A ceramic filter for exhaust gas removal having a honeycomb structure, which is made of a corrugated ceramic paper according to any one of claims 1 to 4 and a ceramic plate-shaped paper. (a) preparing a ceramic paper using a slurry solution of the ceramic fiber, the organic fiber and the organic binder according to any one of claims 1 to 4; (b) forming a ceramic filter having a honeycomb structure by corrugating the ceramic paper, placing ceramic plate-shaped paper on the lower layer, and bonding and winding the ceramic paper together; (c) coating the ceramic filter with an inorganic binder solution; And (d) drying the ceramic filter coated with the inorganic binder solution and firing at a temperature of 800 to 1100 ° C. Method of manufacturing a ceramic filter comprising a. The method of claim 8, wherein the inorganic binder comprises an inorganic colloidal solution, an aluminum phosphate solution, or a mixture thereof selected from the group consisting of alumina sol, silica sol, and clay dispersion solution. . delete

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