Filter material for reducing pressure drop of automobile air conditioning filter and preparation method thereof

Abstract

The present invention belongs to the technical field of filter materials for industrial dust removal. The present invention discloses a filter material for reducing the pressure drop of an automobile air conditioning filter and a preparation method thereof. The filter material for the automobile air conditioning filter comprises, in sequence, a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer. The coarse filter layer and the medium filter layer are first composited into a primary filter material by ultrasonic welding. The welding points of the ultrasonic welding are uniformly distributed linearly along the transverse direction of the primary filter material to form embossing. The embossing coincides with the folds made when the filter is manufactured, and the spacing between the embossings is 10 to 60 mm. One side of the medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in sequence by adhesive composite. The filter material for the automobile air conditioning filter manufactured by the present invention not only enhances the solidity of the material at the folds after folding, but also reduces the pressure drop of the manufactured automobile air conditioning filter and increases the air permeability.

Description

Technical Field

[0001] The invention belongs to the technical field of filter materials for industrial dust removal, and in particular to the technical field of filter materials for automobile air conditioning filters. Background Art

[0002] The core component of an automotive cabin air filter is the filter material, which is generally composed of two or more layers. When multiple layers are laminated, ultrasonic lamination or adhesive lamination is performed directly. Ultrasonic lamination bonds the multiple layers of filter material at the weld points, ensuring uniform distribution of weld points. This creates resistance at these weld points. Not all materials are suitable for ultrasonic lamination. For example, materials containing activated carbon will exhibit poor filter strength if only ultrasonic lamination is used. Adhesive lamination of filter material securely bonds the two adjacent layers. However, for lamination of more than two layers, multiple adhesive laminations are required to achieve a secure bond. This results in a higher adhesive content in the filter material, leading to higher costs and significantly increased resistance.

[0003] Ultrasonic lamination or adhesive lamination will generate resistance at the bonding point, resulting in increased resistance of the filter material and reduced air permeability of the filter after it is made. At the same time, creases created during the filter folding process will also increase resistance and reduce the filter's air permeability. Summary of the Invention

[0004] In response to the above problems, the present invention provides a filter material for reducing the pressure drop of an automobile air-conditioning filter. The filter material adopts a combination of ultrasonic welding and adhesive bonding. The ultrasonic welding points are linearly and evenly distributed along the transverse direction of the primary filter material to form embossing. The embossing coincides with the folding marks when the filter is made, thereby reducing the pressure drop of the filter and improving the air permeability.

[0005] The technical solution adopted by the present invention is: a filter material for reducing the pressure drop of an automobile air-conditioning filter, comprising a coarse-efficiency filter layer, a medium-efficiency filter layer, an activated carbon layer, a nanofiber filter membrane and a support layer; the coarse-efficiency filter layer and the medium-efficiency filter layer are composited into a primary filter material by ultrasonic welding, and the welding points of the ultrasonic welding are linearly and evenly distributed along the transverse direction of the primary filter material to form embossing, the embossing coincides with the folding marks when the filter is made, and the spacing between the embossings is 10 to 60 mm; one side of the medium-efficiency filter layer of the primary filter material is bonded together with the activated carbon layer and the support layer loaded with the nanofiber filter membrane by adhesive composite in sequence.

[0006] Preferably, the size of the ultrasonic welding spot is 0.8 to 1.5 mm 2 , the horizontal spacing is 2 to 20 mm.

[0007] Preferably, the coarse filter layer is one of PET wet-laid staple fiber skeleton cloth, PET dry-laid filament skeleton cloth, PET spunbond non-woven fabric, PP spunbond non-woven fabric, and PP spunlace non-woven fabric.

[0008] Preferably, the medium-efficiency filter layer is one of PP electrostatic cotton and PP melt-blown cloth, with a gram weight of 20 to 60 g / m2.

[0009] Preferably, the activated carbon in the activated carbon layer is one or more of coconut shell activated carbon, fruit shell activated carbon, wood activated carbon, and coal activated carbon, the iodine value is 800-1100 mg / g, the average particle size of the activated carbon is 30-60 mesh, and the amount of activated carbon is 20-400 g / m2.

[0010] Preferably, the support layer is one of PET hot-rolled spunbond non-woven fabric, PET wet-laid short-fiber skeleton fabric, and PET dry-laid long-fiber skeleton fabric.

[0011] The present invention also provides a method for preparing the filter material for reducing the pressure drop of an automobile air conditioning filter, comprising the following steps:

[0012] (1) The coarse filter layer and the medium filter layer are firstly composited into a primary filter material by ultrasonic welding. The ultrasonic welding speed is 0.5-10 m / min, the frequency is 15-40 kHz, and the pressure is 0.1-0.6 MPa. The ultrasonic welding points are uniformly distributed linearly along the transverse direction of the primary filter material to form embossing. The embossing coincides with the folding marks when the filter is made, and the spacing between the embossings is 10-60 mm.

[0013] (2) preparing a nanofiber spinning solution with a mass concentration of 3% to 19%, spinning the nanofiber using electrospinning technology, with the support layer as the receiving substrate, the spinning voltage of 40 to 90 kV, the receiving distance of 190 to 250 mm, and the speed of 0.1 to 6 m / min, to produce a nanofiber filter membrane;

[0014] (3) spraying glue on the nanofiber filter membrane prepared in step (2) to evenly spread the activated carbon on the nanofiber filter membrane to form an activated carbon layer;

[0015] (4) Spraying glue on one side of the medium-efficiency filter layer of the primary filter material obtained in step (1) and compounding it on the activated carbon layer obtained in step (3) to obtain a filter material for reducing the pressure drop of the automobile air conditioning filter.

[0016] Preferably, the glue in steps (3) and (4) is ethylene-vinyl acetate copolymer, and the amount used is 2-10 g / m2.

[0017] Preferably, the material used for the nanofiber spinning solution in step (2) is one or more of polyvinyl alcohol, polyurethane, polyacrylonitrile, polyvinylidene fluoride, and polyamide.

[0018] Beneficial effects

[0019] 1. The present invention adopts a composite method combining ultrasonic welding and adhesive bonding, which can reduce the amount of adhesive used and reduce the resistance of the filter material used in the automobile cabin filter, thereby improving the air permeability of the automobile cabin filter.

[0020] 2. The present invention comprehensively considers the composite process of multi-layer materials and the folding process in the filter manufacturing process, and makes the ultrasonic welding points during the composite of the initial filter material coincide with the folds when the filter material is folded, which effectively reduces the resistance after the composite of the multi-layer materials and improves the air permeability of the automobile air conditioning filter. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to specific examples so that those skilled in the art can better understand the present invention and implement it, but the examples are not intended to limit the present invention.

[0022] The filter material for reducing the pressure drop of an automobile cabin filter prepared in the embodiment and the filter material in the comparative example were made into automobile cabin filters of the same specifications, and the filtration efficiency and pressure drop were tested for comparison.

[0023] Example 1

[0024] A filter material for reducing the pressure drop of an automobile air conditioning filter comprises a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer. The coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material. The ultrasonic welding points are evenly distributed linearly along the transverse direction of the primary filter material to form embossing. The embossing coincides with the folding marks made when the filter is manufactured, and the spacing between the embossings is 10 mm. One side of the medium filter layer of the primary filter material is sequentially bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane by adhesive. The area of ​​the ultrasonic welding point is 0.8 mm. 2 The coarse filter layer is made of PET wet-laid staple fiber fabric, and the medium filter layer is made of PP electrostatic cotton, weighing 60g / m2. The activated carbon layer is coconut shell activated carbon with an iodine value of 1100mg / g, an average particle size of 40 mesh, and a dosage of 400g / m2. The support layer is made of PET hot-rolled spunbond nonwoven fabric.

[0025] The method for preparing the filter material for reducing the pressure drop of the automobile air conditioning filter comprises the following steps:

[0026] (1) PET wet-laid staple fiber skeleton cloth and PP electrostatic cotton were first composited into primary filter material by ultrasonic welding. The ultrasonic welding speed was 0.5 m / min, the frequency was 15 kHz, and the pressure was 0.6 MPa. The ultrasonic welding points were linearly and evenly distributed along the transverse direction of the primary filter material to form embossing. The embossing coincided with the folding marks when making the filter, and the spacing between the embossings was 10 mm.

[0027] (2) A nanofiber spinning solution with a polyvinyl alcohol mass concentration of 3% was prepared, and the spinning was performed using electrospinning technology. PET hot-rolled spunbond non-woven fabric was used as the receiving substrate. The spinning voltage was 40 kV, the receiving distance was 190 mm, and the speed was 0.1 m / min to obtain a nanofiber filter membrane.

[0028] (3) Spray ethylene-vinyl acetate copolymer glue on the nanofiber filter membrane prepared in step (2) at a dosage of 10 g / m2, and evenly spread coconut shell activated carbon on the nanofiber filter membrane to form an activated carbon layer.

[0029] (4) Spraying ethylene-vinyl acetate copolymer glue on one side of the PP electrostatic cotton of the primary filter material obtained in step (1) in an amount of 10 g / m2, and compounding it on the activated carbon layer obtained in step (3) to obtain a filter material for reducing the pressure drop of the automobile air conditioning filter.

[0030] The cabin air filter made of the above materials was tested in accordance with GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test". The dust was A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 93.46%, and the pressure drop is 92.1Pa.

[0031] Comparative Example 1

[0032] A filter material for reducing the pressure drop of an automobile air conditioning filter comprises a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer. The coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material, with the ultrasonic welding points evenly distributed across the surface of the primary filter material. The medium filter layer of the primary filter material is sequentially bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane using adhesive. The ultrasonic welding point area is 0.8mm. 2 The coarse filter layer is made of PET wet-laid staple fiber fabric, and the medium filter layer is made of PP electrostatic cotton, weighing 60g / m2. The activated carbon layer is coconut shell activated carbon with an iodine value of 1100mg / g, an average particle size of 40 mesh, and a dosage of 400g / m2. The support layer is made of PET hot-rolled spunbond nonwoven fabric.

[0033] The preparation method of the filter material for reducing the pressure drop of the automobile air conditioning filter is the same as that of Example 1, except that during the process of ultrasonic welding to form the primary filter material, the ultrasonic welding points are evenly distributed on the surface of the primary filter material.

[0034] According to GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test", the above materials are made into automotive cabin filters of the same specifications. The dust is A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 93.33%, and the pressure drop is 105.8Pa.

[0035] Example 2

[0036] A filter material for reducing the pressure drop of an automobile air conditioning filter, comprising a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer in sequence; the coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material, with the ultrasonic welding points uniformly distributed linearly along the transverse direction of the primary filter material to form embossing, which coincides with the folds made when the filter is manufactured, with a spacing of 60mm between the embossings; one side of the medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in sequence by adhesive compounding. The area of ​​the ultrasonic welding point is 1.5mm 2 The coarse filter layer is made of PET dry-laid filament fabric, and the medium filter layer is made of PP meltblown fabric, weighing 20g / m2. The activated carbon layer is coal-based activated carbon with an iodine value of 800mg / g and an average particle size of 60 mesh. The amount of activated carbon used is 20g / m2. The support layer is made of PET wet-laid staple fiber fabric.

[0037] The method for preparing the filter material for reducing the pressure drop of the automobile air conditioning filter comprises the following steps:

[0038] (1) PET dry filament skeleton cloth and PP meltblown cloth are first composited into primary filter material by ultrasonic welding. The ultrasonic welding speed is 10m / min, 40kHz, and the pressure is 0.1MPa. The ultrasonic welding points are linearly and evenly distributed along the transverse direction of the primary filter material to form embossing. The embossing coincides with the folding marks when making the filter, and the spacing between the embossings is 60mm.

[0039] (2) A nanofiber spinning solution with a polyurethane mass concentration of 19% was prepared, and the spinning was performed using electrospinning technology. PET wet-laid staple fiber skeleton cloth was used as the receiving substrate. The spinning voltage was 90 kV, the receiving distance was 250 mm, and the speed was 6 m / min to obtain a nanofiber filter membrane.

[0040] (3) Spraying ethylene-vinyl acetate copolymer glue on the nanofiber filter membrane prepared in step (2) at a spraying amount of 2 g / m2, and evenly spreading coal-based activated carbon on the nanofiber filter membrane to form an activated carbon layer.

[0041] (4) Spraying ethylene-vinyl acetate copolymer glue on one side of the PP melt-blown cloth of the primary filter material obtained in step (1) at a spraying amount of 2 g / m2, and compounding it on the activated carbon layer obtained in step (3) to obtain a filter material for automobile air conditioning filter.

[0042] The cabin air filter made of the above materials was tested in accordance with GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test". The dust was A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 92.83%, and the pressure drop is 63.2Pa.

[0043] Comparative Example 2

[0044] A filter material for reducing the pressure drop of an automobile air conditioning filter comprises, in sequence, a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer. The coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material, with the ultrasonic welding points evenly distributed across the surface of the primary filter material. The medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in sequence through adhesive bonding. The ultrasonic welding point area is 1.5mm 2 The coarse filter layer is made of PET dry-laid filament fabric, and the medium filter layer is made of PP meltblown fabric, weighing 20g / m2. The activated carbon layer is coal-based activated carbon with an iodine value of 800mg / g and an average particle size of 60 mesh. The amount of activated carbon used is 20g / m2. The support layer is made of PET wet-laid staple fiber fabric.

[0045] The preparation method of the filter material for reducing the pressure drop of the automobile air conditioning filter is the same as that of Example 2, except that during the process of ultrasonic welding to form the primary filter material, the ultrasonic welding points are evenly distributed on the surface of the primary filter material.

[0046] According to GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test", the above materials are made into automotive cabin filters of the same specifications. The dust is A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 92.94%, and the pressure drop is 78.4Pa.

[0047] Example 3

[0048] A filter material for reducing the pressure drop of an automobile air conditioning filter, comprising a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer in sequence; the coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material, with the ultrasonic welding points uniformly distributed linearly along the transverse direction of the primary filter material to form embossing, which coincides with the folds made when the filter is manufactured, with a spacing of 40 mm between the embossings; one side of the medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in sequence by adhesive compounding. The ultrasonic welding point area is 1.2 mm 2The coarse filter layer is made of PET spunbond nonwoven fabric, and the medium filter layer is made of PP meltblown fabric, with a grammage of 30g / m2. The activated carbon layer is composed of coconut shell activated carbon, fruit shell activated carbon, and wood activated carbon, with an iodine value of 1000mg / g, an average particle size of 30 mesh, and an activated carbon dosage of 120g / m2. The support layer is made of PET dry-laid long-fiber skeleton fabric.

[0049] The method for preparing the filter material for reducing the pressure drop of the automobile air conditioning filter comprises the following steps:

[0050] (1) PET spunbond nonwoven fabric and PP meltblown fabric were first composited into primary filter material by ultrasonic welding. The ultrasonic welding speed was 6 m / min, the frequency was 20 kHz, and the pressure was 0.3 MPa. The ultrasonic welding points were uniformly distributed linearly along the transverse direction of the primary filter material to form embossing. The embossing coincided with the folding marks when making the filter, and the spacing between the embossings was 40 mm.

[0051] (2) A nanofiber spinning solution with a polyacrylonitrile mass concentration of 7% was prepared, and the spinning was carried out using electrospinning technology. PET dry-process long-fiber skeleton cloth was used as the receiving substrate. The spinning voltage was 70 kV, the receiving distance was 230 mm, and the speed was 4 m / min to produce a nanofiber filter membrane.

[0052] (3) Spraying ethylene-vinyl acetate copolymer glue on the nanofiber filter membrane prepared in step (2) at a glue dosage of 6 g / m2, and evenly spreading coconut shell activated carbon and fruit shell activated carbon on the nanofiber filter membrane to form an activated carbon layer;

[0053] (4) Spray ethylene-vinyl acetate copolymer glue on one side of the medium-efficiency filter layer of the primary filter material obtained in step (1), with the glue amount being 6 g / m2, and compound it on the activated carbon layer obtained in step (3) to obtain a filter material for automobile air conditioning filter.

[0054] The cabin air filter made of the above materials was tested in accordance with GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test". The dust was A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 95.45%, and the pressure drop is 76.7Pa.

[0055] Comparative Example 3

[0056] A filter material for reducing the pressure drop of an automobile air conditioning filter comprises, in sequence, a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane, and a support layer. The coarse filter layer and the medium filter layer are ultrasonically welded together to form a primary filter material, with the ultrasonic welding points evenly distributed across the surface of the primary filter material. The medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in sequence by adhesive bonding. The ultrasonic welding point area is 1.2mm 2 The coarse filter layer is made of PET dry-laid filament fabric, and the medium filter layer is made of PP meltblown fabric, weighing 20g / m2. The activated carbon layer is coal-based activated carbon with an iodine value of 800mg / g and an average particle size of 60 mesh. The amount of activated carbon used is 20g / m2. The support layer is made of PET wet-laid staple fiber fabric.

[0057] The preparation method of the filter material for reducing the pressure drop of the automobile air conditioning filter is the same as that of Example 3, except that during the process of ultrasonic welding to form the primary filter material, the ultrasonic welding points are evenly distributed on the surface of the primary filter material.

[0058] According to GB / T 32085.1-2015 "Automotive Cabin Filter Part 1 Dust Filtration Test", the above materials are made into automotive cabin filters of the same specifications. The dust is A2 ash. 3 / h air volume, the filtration efficiency for particles with a geometric diameter of 0.3μm is 95.81%, and the pressure drop is 91.2Pa.

Claims

1. A method for preparing a filter material for reducing the pressure drop of an automobile air conditioning filter, characterized in that: The steps include: (1) The coarse filter layer and the medium filter layer are firstly composited into a primary filter material by ultrasonic welding. The ultrasonic welding speed is 0.5~10m / min, the frequency is 15~40kHz, and the pressure is 0.1~0.6MPa. The ultrasonic welding points are uniformly distributed linearly along the transverse direction of the primary filter material to form embossing. The spacing between the embossings is 10~60mm, which coincides with the folding marks when the filter is made. (2) preparing a nanofiber spinning solution with a mass concentration of 3%-19%, and spinning the nanofiber using electrospinning technology, with the support layer as the receiving substrate, the spinning voltage of 40-90 kV, the receiving distance of 190-250 mm, and the speed of 0.1-6 m / min to obtain a nanofiber filter membrane; (3) spraying glue on the nanofiber filter membrane prepared in step (2) to evenly spread the activated carbon on the nanofiber filter membrane to form an activated carbon layer; (4) Spraying glue on one side of the medium-efficiency filter layer of the primary filter material obtained in step (1) and compounding it on the activated carbon layer obtained in step (3) to obtain a filter material for reducing the pressure drop of the automobile air conditioning filter.

2. The method for preparing a filter material for reducing the pressure drop of an automobile cabin filter according to claim 1, wherein: The glue described in steps (3) and (4) is ethylene-vinyl acetate copolymer, and the amount used is 2-10 g / m2.

3. The method for preparing a filter material for reducing the pressure drop of an automobile cabin filter according to claim 1, wherein: The material used for the nanofiber spinning solution in step (2) is one or more of polyvinyl alcohol, polyurethane, polyacrylonitrile, polyvinylidene fluoride, and polyamide.

4. The filter material for reducing the pressure drop of an automobile cabin filter obtained by the preparation method according to any one of claims 1 to 3, characterized in that: It includes a coarse filter layer, a medium filter layer, an activated carbon layer, a nanofiber filter membrane and a support layer; the coarse filter layer and the medium filter layer are composited into a primary filter material by ultrasonic welding, and the welding points of the ultrasonic welding are linearly and evenly distributed along the transverse direction of the primary filter material to form embossing; the embossing coincides with the folding marks when making the filter, and the spacing between the embossings is 10~60mm; one side of the medium filter layer of the primary filter material is bonded to the activated carbon layer and the support layer loaded with the nanofiber filter membrane in turn by adhesive composite.

5. The filter material for reducing the pressure drop of an automobile cabin filter according to claim 4, characterized in that: The welding point area of ​​the ultrasonic welding is 0.8~1.5mm², and the horizontal spacing is 2~20mm.

6. The filter material for reducing the pressure drop of an automobile cabin filter according to claim 4, characterized in that: The coarse filter layer is one of PET wet-laid staple fiber skeleton cloth, PET dry-laid filament skeleton cloth, PET spunbond non-woven fabric, PP spunbond non-woven fabric, and PP spunlace non-woven fabric.

7. The filter material for reducing the pressure drop of an automobile cabin filter according to claim 4, characterized in that: The medium-efficiency filter layer is one of PP electrostatic cotton and PP melt-blown cloth, with a gram weight of 20-60g / ㎡.

8. The filter material for reducing the pressure drop of an automobile cabin filter according to claim 4, characterized in that: The activated carbon in the activated carbon layer is one or more of coconut shell activated carbon, fruit shell activated carbon, wood activated carbon, and coal activated carbon, the iodine value is 800-1100 mg / g, the average particle size of the activated carbon is 30-60 mesh, and the amount of activated carbon is 20-400 g / m2.

9. The filter material for reducing the pressure drop of an automobile cabin filter according to claim 4, characterized in that: The supporting layer is one of PET hot-rolled spunbond non-woven fabric, PET wet-laid short-fiber skeleton fabric and PET dry-laid long-fiber skeleton fabric.