WO2022116973A1 - High-dust-holding capacity and electrostatic dissipation glass fiber filter material, and preparation method therefor - Google Patents

Abstract

A high-dust-holding capacity and electrostatic dissipation glass fiber filter material, comprising an upper surface layer (1), a middle layer (2) and a lower surface layer (3), wherein the upper surface layer (1) is a large-aperture layer having a thickness of 0.2-0.3 mm and an average aperture of 18-50 μm; the middle layer (2) is a pyroelectric fiber layer having a thickness of 0.1-0.2 mm and an average aperture of 8-20 μm; the lower surface layer (3) is a small-aperture layer having a thickness of 0.1-0.2 mm and an average aperture of 1-9 μm; and the upper surface layer (1), the middle layer (2) and the lower surface layer (3) are formed by respectively slurrying each layer of fibers followed by slurry distribution through a three-layer headbox, dehydrating, and drying. The glass fiber filter material, which has a three-layer gradient aperture structure, has a high dust holding capacity and is resistant to layering, and charged particles passing through the pyroelectric fiber layer are not charged or carry extremely few charges under the action of pyroelectric fibers, so that the generation of static electricity in an electronic product production workshop is reduced.

Description

A kind of high dust-holding, static dissipative glass fiber filter material and preparation method thereof technical field

The invention relates to the technical field of glass fiber filter materials, in particular to a high dust-holding capacity, static dissipative glass fiber filter material and a preparation method thereof.

Background technique

With the rapid development of the semiconductor and optoelectronic industries, the production workshops of electronic products have higher and higher requirements for anti-static and air cleanliness. If the air cleanliness does not meet the standard, it will directly cause pollution to the products and affect the performance, yield, and air quality of the products. reliability and longevity. The presence of static electricity will cause dielectric breakdown, resulting in device damage, and easily lead to fire and explosion accidents. Static electricity is also harmful to the human body. Static electricity can absorb a large amount of dust in the air and accumulate toxic substances and bacteria. Long-term exposure to static electricity will make people restless, headache, chest tightness, and difficulty breathing, causing bronchial asthma and arrhythmia.

In order to reduce the generation of static electricity, it is clearly stipulated in the electrostatic protection design of the electronic production workshop that the environmental humidity is not less than 50%; on the premise of not causing damage to the product, it is allowed to spray the preparation or water with humidifying equipment. In addition, hydrofluoric acid is used in the production of electronic products. Hydrofluoric acid is volatile and reacts with the boron element in the glass fiber wool. The generated boron fluoric acid is deposited on the surface of electronic components, which will cause breakdown of electronic components. . GB12158 stipulates that the surface resistivity of electrostatic conductors is equal to or less than 1×10 ⁷ Ω, the surface resistivity of electrostatic subconductors is 1×10 ⁷ ～1×10 ¹¹ Ω, and the surface resistivity of electrostatic non-conductors is equal to or greater than 1×10 ¹¹ Ω.

Electromechanical systems such as purifying air conditioners are an important means to ensure that the air cleanliness of electronic product production workshops meets the specified requirements. Glass fiber filter material has extremely high filtration efficiency, excellent chemical stability and low resistance, and is the preferred filter material for purifying air conditioners However, the existing ordinary glass fiber has no anti-static function, is not resistant to moisture, has high boron content, low dust holding capacity, and has a low service life when used for air purification in electronic product production workshops.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-dust-holding, static-dissipative glass fiber filter material and a preparation method thereof. The glass fiber filter material of the present invention has high dust-holding capacity, anti-static, anti-moisture, long service life, and is especially suitable for electronic products Dust filter in production workshop.

The technical scheme adopted in the present invention is:

A high-dust-holding, static-dissipative glass fiber filter material, comprising an upper layer, a middle layer and a lower layer, the upper layer is a large aperture layer, the thickness is 0.2-0.3 mm, and the average aperture is 18-50 μm; The fiber layer has a thickness of 0.1 to 0.2 mm and an average pore diameter of 8 to 20 μm; the lower layer is a small pore size layer with a thickness of 0.1 to 0.2 mm and an average pore diameter of 1 to 9 μm; the upper layer, the middle layer and the lower layer are composed of fibers of each layer. After pulping, the pulp is distributed through a three-layer headbox, dehydrated and dried to form.

Further, the substrates of the large aperture layer are glass fiber wool and chopped glass fibers with a boron oxide content of less than 2%, and the mass ratio of the glass fiber wool to the chopped glass fibers is (40-92):(2-60).

Further, the base material of the electricity-releasing fiber layer is glass fiber wool and chopped glass fibers with a boron oxide content of less than 2%, and electricity-releasing fibers; the mass ratio of glass fiber wool, electricity-releasing fibers, and chopped glass fibers is: ( 40～92):(2～40):(0～20).

Furthermore, the electricity-releasing fibers are at least one of carbon fibers, steel fibers, copper fibers or nickel fibers, and the electricity-releasing fibers have a diameter of 2-8 μm and a length of 2-15 mm.

Further, the base material of the small aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of less than 2%, and the mass ratio of the glass fiber cotton and chopped glass fiber is: (75～98): (2～15) .

The preparation method of the above-mentioned high-dust-tolerant and static-dissipative glass fiber filter material comprises the following steps:

6.1. Pulping:

Prepare large-aperture layer slurry, disperse glass fiber wool and chopped glass fiber in water according to the mass ratio (40-92): (2-60), adjust the pH of the system to 2.5-4.5, beat and dissolve, and obtain a beating degree of 10 ~34°SR, a suspension with a concentration of 0.9 to 1.4 wt%;

Prepare electricity-releasing fiber layer slurry, disperse glass fiber wool, electricity-releasing fiber and chopped glass fiber in water according to the mass ratio: (40～92):(2～40):(0～20), and adjust the pH of the system to be At 2.5 to 4.5, beating and dissolving to obtain a suspension with a beating degree of 15-39°SR and a concentration of 0.9-1.4wt%;

Prepare small pore size layer slurry, glass fiber wool and chopped glass fiber are dispersed in water according to the mass ratio: (75～98):(2～15), and when the pH of the system is adjusted to 2.5～4.5, beating and dispersing are obtained to obtain a beating degree of 35 ~70°SR, a suspension with a concentration of 0.9 to 1.4 wt%;

6.2. Distributing pulp in headbox: transport each layer of pulp prepared in step 6.1 to the upper, middle and lower layers of the three-layer headbox respectively, so that the pulp of the small aperture layer is evenly distributed in the wire part at a concentration of 0.1-0.2wt% In the bottom layer, the slurry of the electricity-releasing fiber layer is evenly distributed in the upper layer of the small aperture layer with a concentration of 0.1-0.2wt%, and the slurry of the large-aperture layer is evenly distributed in the upper layer of the electricity-releasing fiber layer with a concentration of 0.2-0.3wt%, forming a three-layer structure. Structured wet paper sheets;

6.3. Dehydration forming: the wet paper sheet with three-layer structure is naturally dehydrated and vacuum dewatered to form a wet paper sheet with a moisture content of 55-75%;

6.4. Drying: Wet paper with moisture content of 55-75% is multi-cylinder drying or air-dried to form glass fiber filter material with moisture content of 0.2-1.5%.

Further, before the headbox distributing step, it also includes the steps of filtering and diluting with water the large-aperture layer fiber slurry, the electricity-releasing fiber layer slurry and the small-aperture layer slurry in step 6.2, respectively. The slurry is diluted with water to a concentration of 0.2-0.3 wt %, the electricity-releasing fiber layer slurry is diluted with water to a concentration of 0.1-0.2 wt %, and the small pore size layer slurry is diluted with water to a concentration of 0.1-0.2 wt %.

Further, before the drying step, a sizing step is also included, and the adhesive is applied to the wet paper sheet by a curtain type or a spray type, and the adhesive agent accounts for 2-9% of the total mass of the absolutely dry fibers.

Further, the adhesive is at least one of pure acrylic emulsion, silane-modified acrylic emulsion, polyvinyl alcohol or melamine emulsion.

Further, the drying step also includes the step of applying a waterproofing agent, and when the moisture content of the wet paper sheet is 10-25 wt%, a fluorocarbon, silicone or environmentally friendly PFOA-free waterproofing agent is applied, and the waterproofing agent accounts for 0.5% of the total mass of the dry fiber. ~2%.

Beneficial effects of the present invention:

1. The glass fiber filter material of the present invention has a three-layer structure, the windward surface layer is a large pore size layer with an average pore size of 18-50 μm, the middle layer is a charge-releasing fiber layer with an average pore size of 8-20 μm, and the air outlet surface layer is an average pore size layer. The small pore size layer with a pore size of 1 to 9 μm, the large pore size layer is thicker, and the middle layer and the small pore size layer form a gradient structure in which the pore size and thickness decrease layer by layer from the air inlet direction to the air outlet direction, and the large pore size layer intercepts during filtration. Larger-sized particles and smaller-sized particles pass through the large pore size layer and are trapped in the middle layer or the small pore size layer, the pores of the entire filter material can be fully utilized, the dust holding capacity of the filter material can be improved, and the filter material has a lower pore size. The filter resistance is increased, and the service life of the filter material is improved. The middle layer is the charge-releasing fiber layer. Since the charge-releasing fibers can eliminate or dissipate static electricity, the charged particles passing through the charge-releasing fiber layer are not charged or have very little charge under the action of the charge-releasing fibers, thereby reducing the amount of electrons. The generation of static electricity in the production workshop of the product.

2. The glass fiber filter material of the present invention is formed by pulping each layer of fibers separately and then distributing the pulp through a three-layer headbox, dehydrating and drying. The pulping conditions of each layer of fibers are controlled respectively to obtain three kinds of pulps with different beating degrees and concentrations, and three-layer headbox is used for pulping. Enhancement effect, under the action of pressure and tension, the fibers of each layer are embedded in each other in the vertical direction, forming a multi-layer filter material with a gradient structure. The multi-layer headbox is used to manufacture the filter material with tighter bonding between the fibers of each layer, more continuous transition of the joint, higher moisture removal efficiency, and not easy to delaminate.

3. The glass fiber filter material of the present invention adopts boron-free or low-boron glass fiber cotton and chopped glass fiber, which can reduce the probability that the glass fiber filter material reacts with hydrofluoric acid to generate borofluoric acid, and prevents the generation of boron. The deposition of fluoric acid on the surface of electronic components causes breakdown failure of electronic components.

4. The application of the waterproofing agent can make the glass fiber filter material of the present invention have better moisture resistance, adapt to the working conditions of the electronic product production workshop, and improve the service life of the filter material.

Description of drawings

FIG. 1 is a schematic diagram showing the structure of the high-dust-holding, static-dissipative glass fiber filter material of the present invention.

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

Example 1

Referring to FIG. 1, the present embodiment provides a high-dust-holding, static-dissipative glass fiber filter material, which is composed of an upper layer 1, an intermediate layer 2 and a lower layer 3. The upper layer 1 is a large pore size layer with a thickness of 0.2 mm and an average thickness of 0.2 mm. The pore size is 19 μm; the middle layer 2 is a charge-releasing fiber layer with a thickness of 0.1 mm and an average pore size of 10 μm; the lower layer is a small pore size layer with a thickness of 0.1 mm and an average pore size of 8 μm. The substrates of the large aperture layer are glass fiber wool and chopped glass fibers with a boron oxide content of 1.8%, and the mass ratio of the glass fiber wool to the chopped glass fibers is 40:4. The base material of the charge-releasing fiber layer is glass fiber wool and charge-releasing fibers with a boron oxide content of 1.8%; the mass ratio of glass fiber wool and charge-releasing fibers is 40:2. The electricity-releasing fibers are carbon fibers with a diameter of 2 μm and a length of 3 mm. The base material of the small aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of 1.8%, and the mass ratio of the glass fiber wool and the chopped glass fiber is 75:15.

The glass fiber filter material preparation method of embodiment 1 is:

(1) Pulping:

Prepare large pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 40:4, and adjust the pH of the system to 2.5 for beating and dispersing to obtain a suspension with a beating degree of 20°SR and a concentration of 0.9wt% liquid;

Prepare electricity-releasing fiber layer slurry, disperse glass fiber wool and electricity-releasing fiber in water at a mass ratio of 40:2, adjust the pH of the system to 2.5 for beating and dispersing, and obtain a suspension with a beating degree of 30°SR and a concentration of 0.9wt% liquid;

Prepare small pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 75:15, and adjust the pH of the system to 2.5 for beating and dispersing to obtain a suspension with a beating degree of 35°SR and a concentration of 0.9wt% ;

(2) Sizing: dilute the fiber slurry of the large pore size layer with water to a concentration of 0.2 wt %, the slurry of the electricity-releasing fiber layer with water to a concentration of 0.1 wt %, and the slurry of the small pore size layer with water to a concentration of 0.1 wt %;

(3) Slurry distribution in the headbox: The diluted slurry of each layer is transported to the upper, middle and lower layers of the three-layer headbox respectively, so that the slurry of the small aperture layer is evenly distributed on the bottom layer of the mesh at a concentration of 0.1wt%, releasing The electric fiber layer slurry is uniformly distributed on the upper layer of the small pore size layer with a concentration of 0.1wt%, and the large pore size layer slurry is uniformly distributed on the upper layer of the electricity-releasing fiber layer with a concentration of 0.2wt%, forming a wet paper sheet with a three-layer structure;

(4) Dehydration forming: the wet paper sheet with three-layer structure is formed into a wet paper sheet with a moisture content of 55% after natural dehydration and vacuum dehydration;

(5) Sizing: The pure acrylic emulsion, which accounts for 2% of the total mass of the dry fiber, is applied to the wet paper sheet by curtain sizing, and the moisture content is 60% by vacuum dehydration;

(6) Drying: let the wet paper sheet with a moisture content of 60% pass through a multi-cylinder dryer, and dry it at 90° C. for 25 minutes, so that the moisture content of the wet paper sheet is 25 wt%, and 0.5% of the total dry fiber mass of fluorine The carbon water repellent was evenly applied to the paper sheet with a moisture content of 25 wt%; the paper sheet with the water repellent agent was passed through a multi-cylinder dryer and dried at 150 ° C for 25 minutes to obtain a high dust-holding, static dissipative glass with a moisture content of 1.5%. fiber filter.

Example 2

This embodiment provides a high-dust-tolerant, static-dissipative glass fiber filter material, which is composed of an upper layer 1, an intermediate layer 2 and a lower layer 3, the upper layer 1 is a large aperture layer, the thickness is 0.25mm, and the average aperture is 30μm; The middle layer 2 is a charge-releasing fiber layer with a thickness of 0.12 mm and an average pore size of 15 μm; the lower layer is a small pore size layer with a thickness of 0.12 mm and an average pore size of 5 μm. The base material of the large aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of 1.6%, and the mass ratio of the glass fiber wool to the chopped glass fiber is 60:12. The base material of the electricity-releasing fiber layer is glass fiber wool and electricity-releasing fibers with a boron oxide content of 1.6%; the mass ratio of the glass fiber wool and electricity-releasing fibers is 60:10, and the electricity-releasing fibers are 3 μm in diameter and 6 mm in length of steel fibers. The base material of the small aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of 1.6%, and the mass ratio of the glass fiber wool and the chopped glass fiber is 80:12.

The glass fiber filter material preparation method of embodiment 2 is:

(1) Pulping:

Prepare large-pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 60:12, adjust the pH of the system to 3, beat and dissolve, and obtain a suspension with a beating degree of 13°SR and a concentration of 1wt% ;

Prepare electricity-releasing fiber layer slurry, disperse glass fiber wool and electricity-releasing fiber in water at a mass ratio of 60:10, adjust the pH of the system to 3 for beating and dispersing, and obtain a suspension with a beating degree of 25°SR and a concentration of 1wt% ;

Prepare small aperture layer slurry, glass fiber wool and chopped glass fiber are dispersed in water at a mass ratio of 80:3, and when the pH of the system is adjusted to 3, beating and dispersing are obtained to obtain a suspension with a beating degree of 40°SR and a concentration of 1wt%;

(2) Sizing: the fiber slurry of the large pore size layer is diluted with water to a concentration of 0.24wt%, the slurry of the electricity-releasing fiber layer is diluted with water to a concentration of 0.12wt%, and the slurry of the small pore size layer is diluted with water to a concentration of 0.12wt%;

(3) Headbox pulping: After dilution, each layer of pulp is transported to the upper, middle and lower layers of the three-layer headbox, and the pulp of the small aperture layer is evenly distributed on the bottom layer of the mesh at a concentration of 0.12wt%, and the electricity-releasing fibers The layer slurry is uniformly distributed on the upper layer of the small pore size layer with a concentration of 0.12wt%, and the large pore size layer slurry is uniformly distributed on the upper layer of the charge-releasing fiber layer with a concentration of 0.24wt%, forming a wet paper sheet with a three-layer structure;

(4) Dehydration forming: the wet paper sheet with three-layer structure is formed into a wet paper sheet with a moisture content of 65% after natural dehydration and vacuum dehydration;

(5) Sizing: The silane-modified acrylic emulsion, which accounts for 4% of the total mass of the dry fiber, is applied to the wet paper sheet by curtain sizing, and the moisture content is 62% by vacuum dehydration;

(6) Drying: let the wet paper sheet with a moisture content of 62% pass through a multi-cylinder dryer, and dry it at 80°C for 30 minutes, so that the moisture content of the wet paper sheet is 20 wt%, and the organic The silicon water repellent was evenly applied to the paper sheet with a moisture content of 20 wt%; the paper sheet with the water repellent agent was passed through a multi-cylinder dryer and dried at 140° C. for 30 minutes to obtain a high dust-holding, electrostatic dissipative glass with a moisture content of 0.8%. fiber filter.

Example 3

This embodiment provides a high-dust-tolerant and static-dissipative glass fiber filter material, which is composed of an upper layer 1, an intermediate layer 2 and a lower layer 3, and the upper layer 1 is a large aperture layer with a thickness of 0.28 mm and an average aperture of 40 μm; The middle layer 2 is a charge-releasing fiber layer with a thickness of 0.15 mm and an average pore size of 12 μm; the lower layer is a small pore size layer with a thickness of 0.13 mm and an average pore size of 3 μm. The base material of the large aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of 1.5%, and the mass ratio of the glass fiber wool to the chopped glass fiber is 80:35. The base material of the charge-releasing fiber layer is glass fiber wool with boron oxide content of 1.5%, chopped glass fiber and charge-releasing fiber; the mass ratio of glass fiber wool, charge-releasing fiber and chopped glass fiber is 80:10:10. The electricity-releasing fibers are copper fibers with a diameter of 5 μm and a length of 9 mm. The base material of the small aperture layer is glass fiber wool and chopped glass fiber with a boron oxide content of 1.5%, and the mass ratio of the glass fiber wool and the chopped glass fiber is 85:10.

The glass fiber filter material preparation method of embodiment 3 is:

(1) Pulping:

Prepare large-pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 80:35, and adjust the pH of the system to 3.5 for beating and dispersing to obtain a suspension with a beating degree of 11°SR and a concentration of 1.2wt% liquid;

Prepare the slurry of the electricity-releasing fiber layer, disperse the glass fiber wool, electricity-releasing fiber and chopped glass fiber in a mass ratio of 80:10:10, disperse them in water, and adjust the pH of the system to 3.5 for beating and dispersing to obtain a beating degree of 28° SR, a suspension at a concentration of 1.2 wt%;

Prepare small pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 85:10, and adjust the pH of the system to 3.5 for beating and dispersing to obtain a suspension with a beating degree of 50°SR and a concentration of 1.2wt% ;

(2) Sizing: the fiber slurry of the large pore size layer is diluted with water to a concentration of 0.28wt%, the slurry of the electricity-releasing fiber layer is diluted with water to a concentration of 0.15wt%, and the slurry of the small pore size layer is diluted with water to a concentration of 0.13wt%;

(3) Headbox distributing slurry The diluted slurry of each layer is transported to the upper, middle and lower layers of the three-layer headbox, so that the slurry of the small pore size layer is evenly distributed on the bottom layer of the mesh with a concentration of 0.13wt%, releasing electricity. The fiber layer slurry is uniformly distributed on the upper layer of the small pore size layer with a concentration of 0.15wt%, and the large pore size layer slurry is uniformly distributed on the upper layer of the electricity-releasing fiber layer with a concentration of 0.28wt%, forming a wet paper sheet with a three-layer structure;

(4) Dehydration forming: the wet paper sheet with three-layer structure is formed into a wet paper sheet with a moisture content of 70% after natural dehydration and vacuum dehydration;

(5) Sizing: the polyvinyl alcohol emulsion, which accounts for 6% of the total mass of the dry fiber, is applied to the wet paper sheet by means of spray sizing, and the water content is 65% by vacuum dehydration;

(6) Drying: let the wet paper sheet with a moisture content of 65% pass through an air dryer, and dry it at 90° C. for 40 minutes, so that the moisture content of the wet paper sheet is 15 wt%, and 1.5% of the total mass of the dry fiber is made of silicone The water-repellent agent was uniformly applied to the paper sheet with a moisture content of 15 wt%; the paper sheet with the water-repellent agent applied was passed through an air dryer and dried at 180° C. for 20 minutes to obtain a high-dust-holding, static-dissipative glass fiber filter with a moisture content of 0.2%. material.

Example 4

This embodiment provides a high-dust-tolerant, static-dissipative glass fiber filter material, which is composed of an upper layer 1, an intermediate layer 2 and a lower layer 3, and the upper layer 1 is a large aperture layer with a thickness of 0.3 mm and an average aperture of 48 μm; The middle layer 2 is a charge-releasing fiber layer with a thickness of 0.2 mm and an average pore size of 20 μm; the lower layer is a small pore size layer with a thickness of 0.2 mm and an average pore size of 1 μm. The substrates of the large aperture layer are glass fiber wool and chopped glass fibers with a boron oxide content of 1.3%, and the mass ratio of the glass fiber wool to the chopped glass fibers is 92:60. The base material of the charge-releasing fiber layer is glass fiber wool with boron oxide content of 1.3%, chopped glass fiber and charge-releasing fiber; the mass ratio of glass fiber wool, charge-releasing fiber, and chopped glass fiber is 92:40:2. The electricity-releasing fibers are nickel fibers with a diameter of 8 μm and a length of 15 mm. The substrates of the small aperture layer are glass fiber wool and chopped glass fibers with a boron oxide content of 1.3%, and the mass ratio of the glass fiber wool to the chopped glass fibers is 98:2.

The glass fiber filter material preparation method of embodiment 4 is:

(1) Pulping:

Prepare large pore size layer slurry, disperse glass fiber wool and chopped glass fiber in water at a mass ratio of 92:60, and adjust the pH of the system to 4 for beating and dispersing to obtain a suspension with a beating degree of 10°SR and a concentration of 1.4wt% liquid;

Prepare the slurry of the electricity-releasing fiber layer, disperse the glass fiber wool, the electricity-releasing fiber and the chopped glass fiber in a mass ratio of 92:40:2, and disperse them in water. When the pH of the system is adjusted to 4.5, beating and dispersing are obtained, and the beating degree is 15°. SR, a 1.4 wt% suspension;

Prepare small pore size layer slurry, glass fiber wool and chopped glass fiber are dispersed in water in a mass ratio of 98:2, and when the pH of the system is adjusted to 4, beating and dispersing are obtained to obtain a suspension with a beating degree of 70°SR and a concentration of 1.4wt% ;

(2) Sizing: the fiber slurry of the large pore size layer is diluted with water to a concentration of 0.3wt%, the slurry of the electricity-releasing fiber layer is diluted with water to a concentration of 0.2wt%, and the slurry of the small pore size layer is diluted with water to a concentration of 0.2wt%;

(3) Headbox pulping: After dilution, each layer of pulp is transported to the upper, middle and lower layers of the three-layer headbox, and the pulp of the small aperture layer is evenly distributed on the bottom layer of the mesh at a concentration of 0.2wt%, and the discharge fibers The layer slurry is uniformly distributed on the upper layer of the small pore size layer with a concentration of 0.2wt%, and the large pore size layer slurry is uniformly distributed on the upper layer of the electricity-releasing fiber layer with a concentration of 0.3wt% to form a wet paper sheet with a three-layer structure;

(4) Dehydration forming: the wet paper sheet with three-layer structure is formed into a wet paper sheet with a moisture content of 75% after natural dehydration and vacuum dehydration;

(5) Sizing: The acrylic emulsion and melamine emulsion, which account for 9% of the total dry fiber mass, are applied to the wet paper sheet in a ratio of 1:1 by means of spray sizing, and dehydrated by vacuuming to a moisture content of 70%. %;

(6) Drying: let the wet paper sheet with a moisture content of 70% pass through an air dryer, and dry it at 70 ° C for 90 minutes, so that the moisture content of the wet paper sheet is 10 wt%, which will account for 2% of the total dry fiber mass. The PFOA-free water repellent was evenly applied to the paper sheet with a moisture content of 10wt%; the paper sheet with the water repellent agent was passed through an air dryer and dried at 160°C for 15 minutes to obtain a high dust-holding, static dissipative glass with a moisture content of 0.5%. fiber filter.

The commercially available filter material 1 is a F9W single-layer glass fiber filter material with a thickness of 0.4 mm.

The commercially available filter material 2 is an H11W single-layer glass fiber filter material with a thickness of 0.5 mm.

The commercially available filter material 3 is a 49W single-layer glass fiber filter material with a thickness of 0.55 mm.

The commercially available filter material 4 is an H14W single-layer glass fiber filter material with a thickness of 0.65 mm.

Performance Testing:

1. The filtration performance of the glass fiber filter material of the embodiment of the present invention and the commercially available glass fiber filter material are respectively tested, according to the test standard CRAA431.3, using TSI8130 (0.3μm@5.3cm/s).

2. Conduct electrical conductivity tests on the glass fiber filter material of the embodiment of the present invention and the commercially available glass fiber filter material respectively. According to GB12158 standard, ZC-90E high insulation resistance measuring instrument (detection voltage 500V) is used.

The test results are shown in Table 1-2 below.

Table 1 Test results of glass fiber filter material filtration performance

Filtration efficiency (%)

Filter resistance (Pa)

Example 1	88	65
Commercial filter material 1	88	82
Example 2	99	130
Commercial filter material 2	99	168
Example 3	99.99	260
Commercial filter media 3	99.99	350
Example 4	99.997	294
Commercial filter material 4	99.996	380

Table 2 Test results of surface resistivity and dust holding capacity of glass fiber filter material

	Surface Resistivity (Ω)	Dust holding capacity (g/m 2 )
Example 1	8.32×10 9	140

Commercial filter material 1	4.63×10 13	115
Example 2	5.28×10 8	145
Commercial filter material 2	3.51×10 13	110
Example 3	9.47×10 8	150
Towel purchase filter material 3	5.78×10 12	105
Example 4	2.04×10 7	155
Towel purchase filter material 4	7.32×10 12	100

It can be seen from the test results in Tables 1 and 2 that under the same filtration efficiency, the filtration resistance of the glass fiber filter materials prepared in Examples 1 to 4 is 22% to 25% lower than that of the commercially available filter materials, and the dust holding capacity is lower than that of the commercially available filter materials. The filter material is increased by 20% to 50%. The glass fiber filter materials prepared in Examples 1 to 4 are all electrostatic subconductors, and the commercially available filter materials are all electrostatic nonconductors.

The glass fiber filter material prepared in Example 1 was used in the purification air-conditioning system of the electronic product production workshop, and the fan operating power of the purification air-conditioning system was reduced by about 10%; and the replacement cycle of the glass fiber filter material was extended from the original half a year to 8 More than a month, the number of electrostatic sparks in the workshop has dropped to about 50% of the original.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. A high-dust-holding, static-dissipative glass fiber filter material is characterized in that it comprises an upper layer, a middle layer and a lower layer, the upper layer is a large aperture layer, the thickness is 0.2-0.3 mm, and the average aperture is 18-50 μm; The layer is a charge-releasing fiber layer with a thickness of 0.1-0.2mm and an average pore diameter of 8-20μm; the lower layer is a small pore size layer with a thickness of 0.1-0.2mm and an average pore diameter of 1-9μm; the upper layer, the middle layer and the lower layer The fibers of each layer are pulped separately and then distributed through a three-layer headbox, dewatered and dried to form.
2. The high-dust-holding, static-dissipative glass fiber filter material according to claim 1, wherein the base material of the large pore size layer is glass fiber wool and chopped glass fiber with a boron oxide content of less than 2%, glass fiber wool and chopped glass fiber The mass ratio of glass fiber is (40～92):(2～60).
3. The high-dust-holding, static-dissipative glass fiber filter material according to claim 1, wherein the base material of the charge-releasing fiber layer is glass fiber cotton and chopped glass fibers with a boron oxide content of less than 2%, and charge-releasing fibers; The mass ratio of glass fiber wool, charge-releasing fiber and chopped glass fiber is: (40～92):(2～40):(0～20).
4. The high-dust-holding, static-dissipative glass fiber filter material according to claim 3, wherein the discharge fiber is at least one of carbon fiber, steel fiber, copper fiber or nickel fiber, and the diameter of the discharge fiber is 2 ~8μm, length is 2~15mm.
5. The high-dust-tolerant and static-dissipative glass fiber filter material according to claim 1, wherein the base material of the small pore size layer is glass fiber wool and chopped glass fiber with a boron oxide content of less than 2%, glass fiber wool and chopped glass fiber. The mass ratio of glass fiber is: (75～98):(2～15).
6. The method for preparing a high-dust-holding, static-dissipative glass fiber filter material according to any one of claims 1 to 5, wherein the method comprises the following steps:

   6.1. Pulping:

   Prepare large aperture layer slurry, disperse glass fiber wool and chopped glass fiber in water according to the mass ratio (40～92): (2～60), adjust the pH of the system to be 2.5～4.5, beat and dissolve, and obtain a beating degree of 10 ~34°SR, a suspension with a concentration of 0.9 to 1.4 wt%;

   Prepare electricity-releasing fiber layer slurry, disperse glass fiber wool, electricity-releasing fiber and chopped glass fiber in water according to the mass ratio: (40～92):(2～40):(0～20), and adjust the pH of the system to be At 2.5 to 4.5, beating and dissolving to obtain a suspension with a beating degree of 15-39°SR and a concentration of 0.9-1.4wt%;

   Prepare small pore size layer slurry, glass fiber wool and chopped glass fiber are dispersed in water according to the mass ratio: (75～98):(2～15), adjust the pH of the system to be 2.5～4.5, beat and dissolve, and obtain a beating degree of 35 ~70°SR, a suspension with a concentration of 0.9 to 1.4 wt%;

   6.2. Headbox pulp distribution: transport each layer of pulp prepared in step 6.1 to the upper, middle and lower layers of the three-layer headbox respectively, so that the pulp of the small aperture layer is evenly distributed in the wire part at a concentration of 0.1-0.2wt% In the bottom layer, the slurry of the electricity-releasing fiber layer is evenly distributed in the upper layer of the small aperture layer with a concentration of 0.1-0.2wt%, and the slurry of the large-aperture layer is evenly distributed in the upper layer of the electricity-releasing fiber layer with a concentration of 0.2-0.3wt%, forming a three-layer structure. Structured wet paper sheets;

   6.3. Dehydration forming: the wet paper sheet with three-layer structure is formed by natural dehydration and vacuum dehydration to form a wet paper sheet with a moisture content of 55-75%;

   6.4. Drying: Wet paper with a moisture content of 55-75% is multi-cylinder drying or air-dried to form a glass fiber filter material with a moisture content of 0.2-1.5%.
7. The preparation method according to claim 6, characterized in that, before the headbox distributing step, the step further comprises, respectively, the large-aperture-layer fiber slurry, the charge-releasing fiber-layer slurry, and the small-aperture layer slurry in step 6.2. In the steps of filtration and dilution with water, the fiber slurry of the large pore size layer is diluted with water to a concentration of 0.2-0.3wt%, the slurry of the electricity-releasing fiber layer is diluted with water to a concentration of 0.1-0.2wt%, and the slurry of the small pore size layer is diluted with water to a concentration of 0.1-0.2 wt% concentration.
8. The preparation method according to claim 6, characterized in that, before the drying step, it further comprises a step of sizing, and the adhesive is applied to the wet paper sheet by a curtain type or a spray type, and the adhesive accounts for 2-9% of the total mass of the dry fiber. %.
9. The preparation method according to claim 8, wherein the adhesive is at least one of pure acrylic emulsion, silane-modified acrylic emulsion, polyvinyl alcohol or melamine emulsion.
10. The preparation method according to claim 6, characterized in that, the drying step further comprises the step of applying a water repellent, and when the moisture content of the wet paper sheet is 10-25 wt %, a fluorocarbon, silicone or environmentally friendly PFOA-free water repellent is applied , the water repellent accounts for 0.5 to 2% of the total mass of the dry fiber.

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