CN109310936A

CN109310936A - Filter medium comprising thin staple fiber

Info

Publication number: CN109310936A
Application number: CN201780035823.XA
Authority: CN
Inventors: 斯内赫·斯瓦米纳坦; 斯维特拉娜·克鲁普尼科夫
Original assignee: Hollingsworth and Vose Co
Current assignee: Hollingsworth and Vose Co
Priority date: 2016-06-09
Filing date: 2017-06-08
Publication date: 2019-02-05
Also published as: EP3468689A4; WO2017214419A1; EP3468689A1

Abstract

Provide the filter medium comprising thin staple fiber and related components, systems, and methods associated with the filter medium.In some embodiments, filter medium may include the layer (for example, wet laid layer) of the polymer short fiber comprising average diameter relatively small (for example, less than or equal to about 1 micron).Polymer short fiber layer can be designed to assign the desired characteristic of the filter medium for example high particulate efficiency and/or fluid separative efficiency, while there is relatively minimal adverse effect to one or more characteristics important for given application of the filter medium or not adversely affect.Filter medium as described herein may be particularly useful for a variety of applications.

Description

Filter medium comprising thin staple fiber

Related application

This application claims the entitled " filter medium (Filter comprising thin staple fiber submitted on June 9th, 2016 Media Including Fine Staple Fibers) " U. S. application the 15/178th, 199 priority, the U.S. Shen It please be entitled " filter medium (the Filter Media Including comprising thin staple fiber submitted on December 15th, 2014 Fine Staple Fibers) " U. S. application the 14/569th, 909 part continuation application, wherein each piece passes through reference It is integrally incorporated herein.

Technical field

Embodiment of the present invention is generally related to can be used for a variety of applications (for example, fuel is answered comprising thin staple fiber With) filter medium, and in particular, to comprising thin staple fiber have enhancing performance characteristic filter medium.

Background technique

Filter element can be used to remove pollutant in numerous applications.Such element may include can be by the net of fiber The filter medium of formation.Web provides the porous structure for allowing fluid (for example, gas, liquid) to flow through the medium.In fluid The contaminant particle (for example, dust particles, soot particulates) contained can be trapped on web or in web.According to answering With, it can be by filter media design at having different performance characteristics, such as the fluid separative efficiency such as fuel/water separation effect of raising Rate, and/or the particle separative efficiency of raising.

In some applications, filter medium may include one or more layers comprising synthetic fibers.Although in the presence of comprising The filter medium of synthetic fibers, but the improvement of the performance characteristic (for example, efficiency) of the layer in medium will be beneficial.

Summary of the invention

Provide filter medium and associated component associated with the filter medium, system and side comprising thin staple fiber Method.In some cases, the theme of the application is related to be mutually related product, the substitution solution of particular problem, and/or knot A variety of different purposes of structure and composition.

In one group of embodiment, a series of filter mediums are provided.In some embodiments, filter medium includes the One layer, the first layer includes that avarage fiber diameter is less than or equal to about 3 microns and average length is less than or equal to about 10cm's More than first polymer short fiber.Filter medium further includes the second layer and third layer, and the second layer includes avarage fiber diameter Fiber greater than or equal to about 4 microns, wherein the third layer is non-wet laid layer.First layer, the second layer and third layer At least one surface is that surface is modified.The air penetrability of filter medium is 0.3CFM to 300CFM, fixed weight (basis weight) For 5g/m²To 1000g/m²。

In another embodiment, filter medium includes surface reforming layer, and the surface reforming layer includes average fiber Diameter is less than or equal to about 1 micron and more than first piece polymer short fiber of the average length less than or equal to about 10cm, wherein One layer of thickness is less than or equal to about 0.2mm.Filter medium further includes the second layer, and the second layer includes that avarage fiber diameter is big In or equal to about 4 microns of fiber, the wherein dry Mullen burst strength (dry Mullen burst strength) of filter medium For 0.5psi to 200psi.

In another embodiment, filter medium includes surface reforming layer, and the surface reforming layer includes average diameter More than second of more than first polymer short fiber and average diameter less than or equal to 1 micron less than or equal to about 1 micron is poly- Object staple fiber is closed, wherein the water contact angle of first layer is about 30 degree to 165 degree.Filter medium further includes the second layer, and described second Layer includes fiber of the average diameter greater than or equal to about 4 microns, and wherein the air penetrability of filter medium is 0.3CFM to 300CFM, with And determining weight is 5g/m²To 1000g/m²。

In another embodiment, filter medium includes first layer, and the first layer is less than comprising avarage fiber diameter Or equal to about 1 micron and more than first piece polymer short fiber of the average length less than or equal to about 10cm.Filter medium further includes Second non-wet laid layer and mesh layer, the second non-wet laid layer include avarage fiber diameter greater than or equal to about 4 The fiber of micron.

Additionally provide the filter element including filter medium one or more above-mentioned and as described herein.

It additionally provides using one or more above-mentioned and as described herein filter medium and/or filter element filtering fluid Method.

When considered in conjunction with the accompanying drawings, by described in detail below, this hair to each non-limiting embodiments of the invention Other bright advantages and new feature will be apparent.It include conflicting and/or not in this specification and the file that is incorporated by reference into In the case where consistent disclosure, answer subject to the present specification.If two or more file packets being incorporated by reference into Conflict and/or inconsistent disclosure relative to each other are included, then should be subject to effective date later file.

Detailed description of the invention

Non-limiting embodiments of the invention are described by way of example with reference to the accompanying drawings, these attached drawings are schematic And be not intended to drawn to scale.Each identical or almost the same component illustrated in the figure is usually by same digital representation.For For the sake of clear, come not needing diagram so that those of ordinary skill in the art understand place of the invention, be not each attached Each component is labeled in figure, nor each of each embodiment of the invention part is shown.In the accompanying drawings:

Fig. 1 is the schematic diagram for showing the section of the filter medium according to one group of embodiment, the filter medium include comprising The layer of thin staple fiber；

Fig. 2A is the schematic diagram for showing the section according to one group of embodiment including multiple layers of filter medium；

Fig. 2 B is the schematic diagram for showing the section according to one group of embodiment including multiple layers of another filter medium；

Fig. 2 C is the schematic diagram for showing the section according to one group of embodiment including multiple layers of another filter medium；

Fig. 2 D is the schematic diagram for showing the section according to one group of embodiment including multiple layers of another filter medium；

Fig. 3 A is the schematic diagram for showing the modified surface according to one of the layer of one group of embodiment；And

Fig. 3 B is the schematic diagram for showing the section of the filter medium according to one group of embodiment.

Specific embodiment

Provide filter medium and associated component associated with the filter medium, system and side comprising thin staple fiber Method.In some embodiments, filter medium may include relatively small (for example, less than or equal to about 1 micron) comprising average diameter Polymer short fiber layer (for example, wet laid layer).Polymer short fiber layer can be designed to assign filter medium institute's phase For example high particulate efficiency of the characteristic of prestige and/or high fluid separative efficiency, while to the important for given application of filter medium One or more characteristics have and relatively minimal adverse effect or not adversely affect.For example, it is short to add polymer Fibrous layer with improve fuel filter medium so that gained fuel filter element particulate efficiency and/or fuel: water separative efficiency.It can Realize that such efficiency is improved by using the glass fibre of relatively low (or zero) amount, this may be in some filtration applications It is desired.Filter medium as described herein may be particularly useful for a variety of applications, such as fuel filter, hydraulic filtering, lubricating oil mistake Filter, air filtration and water filtering.

In some typical filter medias, can be realized by adding one or more layers high particulate efficiency and/ Or fluid separative efficiency, such layer may negatively affect one or more characteristics of medium, limit the practicability of medium, And/or increase the difficulty and/or expense of manufacture filter medium.For example, being designed to that the extra play improved efficiency may be comprising less It is expected that for certain filtering fluids and/or the material (for example, glass fibre) of condition.In some cases, be designed to improve with Big thickness (the substantial of the specific extra play of the efficiency of other features (for example, small average pore size) combination of medium Thickness the pressure drop that) may cause filter medium dramatically increases.Subsequent manufacturing procedures such as pleating may also be by specific additional The thickness effect of layer.For example, there may be less pleats for thicker medium.As another example, since thickness is larger, filtering element is crossed The ratio dust containing capacity (that is, dust containing capacity of per unit thickness) of part may be decreased.In some cases, specific extra play may significant shadow Ring the easiness of filter medium manufacturer.For example, extra play may need dedicated equipment or technology to manufacture medium, need with The different equipment of equipment of other layers in filter medium is formed, and/or system needed for manufacture filter medium may be dramatically increased Make time or step.For example, being designed to that the specific extra play improved efficiency may need layering step, in some cases, layer Closing step may cause dust containing capacity to reduce due to used nip pressure (nip pressure) and adhesive.Therefore, it needs Want can to assign beneficial characteristics such as particulate efficiency and fluid separative efficiency without negatively affecting one of filter medium or more The layer of the manufacture of multiple characteristics and/or filter medium.

In some embodiments, the layer comprising thin polymer short fiber is not subjected to the one of conventional layer as described herein A or more limitation.It can be gathered by commonly using manufacturing process (for example, wet laying process) using average diameter is relatively small Object staple fiber forming layer is closed, such layer can provide high particulate efficiency and/or fluid separative efficiency, while to filter medium One or more characteristics have and relatively minimal adverse effect or not adversely affect.In some embodiments, this The thin polymer short fiber layer of sample may include the thin polymer short fiber of relative high weight percentage.For example, the layer can account in layer Total fiber greater than or equal to about 50 weight %, greater than or equal to about 75 weight %, greater than or equal to about 90 weight %, be greater than Or it is equal to about 95 weight % or 100 weight %.It is not intended to be limited to theory, it is believed that along with relative high weight percentage in layer Polymer short fiber small fiber diameter this layer can be made to have relatively high surface area, relatively small " permeability aperture refers to Number (Perm.Pore Index) " (is defined as [mean flow pore size (μm)/(permeability (CFM))^0.5]；E.g., less than or equal to About 6, less than or equal to about 5, less than or equal to about 4, less than or equal to about 3.5, less than or equal to about 3 or it is less than or equal to About 2.5) and/or relatively small thickness (for example, less than or equal to about 0.2mm), it obtains relatively high than dust containing capacity and/or high Particulate efficiency.

In some embodiments, the composition of the thin polymer short fiber in optional layer is to assign other desired spies Property.For example, certain detail polymer short fiber (for example, hydrophobic fiber) can be used to form the layer with specific wetability.With mistake The wetability of the feature of the other layer such as thin polymer short fiber layer of wetability combination can assign filter medium height in filter medium Fluid separative efficiency.In certain embodiments, the composition of thin polymer short fiber may be selected so that relatively high in addition to having Efficiency except, polymer short fiber layer may include seldom or do not include for give the undesirable material of filtration application.

In certain embodiments, one or more layers of filter medium are (for example, the layer comprising thin staple fiber, second Layer) total composition may be designed to assign beneficial characteristics, such as the fluid separative efficiency of raising.For example, in some embodiments, Filter medium may include two or more layers for being designed to improve fluid separative efficiency (for example, fuel-water separative efficiency).Layer One of (for example, layer, the second layer comprising thin staple fiber) or more person can have such at least part surface, this is extremely Few a part of surface, which is modified into, changes and/or improves wetting of the surface relative to particular fluid (for example, fluid to be separated) Property.In some such situations, feature (for example, wetability) group of layer other in the wetability of modified layer and filter medium Conjunction can assign filter medium high fluid separative efficiency.

As described herein, can in filter medium use it is relatively small (for example, micro- less than or equal to about 1 comprising average diameter Rice, less than or equal to about 500 microns) polymer short fiber layer to provide high particulate efficiency and/or high fluid separation Efficiency.The non-limiting example of filter medium including such layer is shown in Fig. 1.In some embodiments, filter medium 10 It may include first layer 15 and the second layer 20, first layer 15 includes thin polymer short fiber.In certain embodiments, layer 15 and layer 20 can direct neighbor as shown in Figure 1.

As used herein, can be with this layer of direct neighbor when being referred to as with another layer " adjacent " for one layer, or it can also There are middle layers.Mean that there is no middle layers with the layer of another layer " direct neighbor ".

In some such embodiments, thin short fiber layers be may be formed on layer 20.For example, wet-laying work can be used Skill is formed together layer 15 and layer 20.It in another example, can be by non-wet laying process (for example, melt-blown, electrostatic spinning, gas Flow networking, spunbond, spun lacing, power spin (forcespun), combing) forming layer 20, and can on non-wet laid layer forming layer 15.In some embodiments of 20 direct neighbor of wherein layer 15 and layer, resin (and/or the object between the fiber of layer can be used Reason interaction) layer is kept together, and do not use adhesive or combined process.It in other embodiments, can be through Layer 15 is attached on layer 20 by adhesive or other combined process.In some embodiments, layer 15 and layer 20 can be each other Indirect neighbor, and one or more middle layers (for example, scrim layer, mesh) separate these layers.In certain implementations In scheme, the layer comprising thin polymer short fiber can be in the upstream of the second layer, as shown in Figure 1.In other embodiments, it wraps Layer containing thin polymer short fiber can be in the downstream of the second layer.

In some embodiments, the second layer 20 can have with first layer 15 (for example, comprising thin polymer short fiber Layer) different one or more characteristics.For example, the second layer may include the average diameter fiber bigger than first layer.Some Under such circumstances, the second layer may include fiber of the average diameter greater than or equal to about 4 microns.In some cases, the second layer Not comprising any thin polymer short fiber (for example, average diameter is less than or equal to about 3 microns or less than or equal to about 1 micron Polymer short fiber).In some cases, the second layer is free of any polymer short fiber at all.In some embodiments, The second layer can have the wetability different from first layer.For example, in some embodiments, first layer can have than the second layer more Big hydrophobicity.In some such embodiments, first layer can be to be hydrophobic, and the second layer can be hydrophilic.At other In embodiment, the wetability of first layer and the second layer can be similar.In some cases, the second layer can have bigger than first layer Hydrophobicity.In some embodiments, the wetting sex differernce between layer 15 and layer 20 can make filter medium have high fluid Separative efficiency, as described in greater detail below.

In some embodiments, filter medium 10 may include be arranged in first layer 15 upstream and/or one of downstream Or more optional layer 25, as shown in Figure 1.One or more optional layers can be any suitable layer.For example, in some implementations In scheme, one or more optional layers can be supporting layer (for example, mesh), wall, scrim, basal layer, efficiency layer (for example, being mainly used for increasing the efficiency or β ratio (upstream average grain number (C of filter medium₀) and downstream average grain number (C) Ratio) layer), discharge layer (for example, layer for preventing filter medium supersaturation and liquid being allowed to be discharged) and/or capacity layer (for example, layer for retaining particulate matter and preventing other layer from blocking).In some embodiments, filter medium may include Three or more layers.For example, filter medium 10 may include layer 15, layer 20 and third layer 30, layer 15 includes thin staple fiber, is such as schemed Shown in 2A to 2B.In certain embodiments, layer 30 can be supporting layer, for providing support and intensity for filter medium, without One or more filtering features (for example, pressure drop, air penetrability, efficiency) can be negatively affected.In some cases, supporting layer can For mesh support layer (for example, synthetic mesh object, metallic mesh), such as the layer or non-fiber layer that are formed by wire rod.One In a little situations, third layer 30 can be the layer for improving one or more filtering features (for example, service life, dust containing capacity, efficiency) (for example, meltblown layer).In some such embodiments, third layer can be non-wet laid layer.No matter the function of third layer How, in some embodiments, third layer 30 can be in the upstream of layer 15.For example, layer 30 can be located at the upstream of layer 15 and layer 20, As shown in Figure 2 A.In certain embodiments, third layer 30 can be in the downstream of layer 20.For example, layer 30 can be located at layer 15 and layer 20 Downstream, as shown in Figure 2 B.

In some embodiments that wherein filter includes first layer 15, the second layer 20 and third layer 30, filter medium It may also include the 4th layer 40, as shown in Fig. 2 C to 2D.In some such embodiments, the 4th layer in composition and/or function On can be essentially identical or different from third layer 30.For example, the 4th layer can have with third layer substantially the same composition (for example, base This identical fiber type, essentially identical fiber weight percentage).In some cases, can have and third layer for the 4th layer Essentially identical function.For example, filter medium 10 may include first layer 15 (for example, layer comprising thin polymer short fiber), Two layer 25 and two scrim layers (for example, third layer and the 4th layer).In some such embodiments, a scrim layer Can be in the upstream of first layer 15, and another scrim layer can be in the downstream of first layer 15 and/or the second layer 20.In some embodiment party In case, the 4th layer can have the function essentially identical with third layer.Essentially identical function is played in wherein third layer and the 4th layer Embodiment in, third layer and the 4th layer can have identical or different composition.In some embodiments, can have for the 4th layer It is made of different from third layer.For example, the 4th layer 40 can be fibrous layer (for example, meltblown layer), and third layer 30 can be non-fibre It ties up layer (for example, line mesh).In the certain embodiments of wherein third layer and the 4th layer with different compositions, third layer and 4th layer can have the function of it is essentially identical.In some cases, there can be the function different from third layer for the 4th layer.

In some embodiments, third layer 30 (for example, supporting layer, meltblown layer) can in the upstream of first layer 15, and Four layer 40 (for example, meltblown layer, supporting layer) can be in the downstream of first layer 15.For example, third layer 30 can be in the upper of layer 15 and layer 20 Trip, and layer 40 can be in the downstream of layer 15 and layer 20, as shown in Figure 2 C.Alternatively, layer 30 can be in the downstream of layer 15 and layer 20, and layer 40 It can be in the upstream of layer 15 and layer 20.In certain embodiments, both layer 30 and layer 40 can layer 15 and/or layer 20 upstream or Downstream.For example, as shown in Figure 2 D, both layer 30 and layer 40 can be in the upstreams of layer 15.In some such embodiments, layer 30 It can be directly adjacent to each other with layer 40, as shown in Figure 2 D, or indirect neighbor each other.

As described herein, in some embodiments, filter medium may include one or more modified layers.Fig. 3 A extremely It can be seen that the example of modified layer and the filter medium including one or more modified layers in 3B.Such as Fig. 3 A illustratively institute Show, can be modified at least part (for example, at least one surface and/or inside, entire layer) of 55 pairs of layers 50 of material.? In some embodiments, layer (for example, at least one surface of layer and/or inside) can be modified to change and/or improve At least part (for example, at least one surface of layer) of layer relative to particular fluid wetability (for example, keep layer more hydrophilic, Or more hydrophobic).In an example, the water-wetted surface that water contact angle is 60 ° can be modified into water contact angle less than 60 °, such as It is 15 °.In another example, the hydrophobic surface that water contact angle is 100 ° can be modified into water contact angle greater than 100 °, for example, 130 ° or bigger.In some embodiments, at least part of modified (for example, surface is modified) changeable layer is (for example, layer One surface) hydrophily or hydrophobicity so that layer correspondingly has opposite hydrophily or hydrophobicity.For example, can be with hydrophilic Material is (for example, charged materials；Organic hydrophilic material；Inorganic material, such as aluminium oxide, silica, metal) to relative hydrophobic The surface of layer is modified, so that modified surface is hydrophilic.Alternatively, in certain embodiments, it can be with hydrophobic material to phase Hydrophilic layer is modified, so that modifying moieties (for example, at least one surface and/or inside, entire layer) are hydrophobic.One In a little embodiments, layer can have a modified surface (for example, upstream face) and a unmodified surface (for example, downstream table Face).In other embodiments, layer can have two or more modified surfaces (for example, upstream face and downstream surface). In some embodiments, entire layer can be modified.For example, can inside to layer and surface be modified.In certain realities It applies in scheme, the inside of layer can be modified, is modified without one or more outer surfaces to layer.For example, filtering Medium can undergo coating procedure (for example, chemical vapor deposition) so that layer cellular internal be coated while internal layer and/or One or more outer surfaces of bottom are not coated.

In general, any suitable layer in filter medium can be modified layer.In some embodiments, as shown in Figure 3B, Filter medium may include one or more layers, and one or more layer is in one or more surfaces and/or inside There is material at least part.For example, filter medium 10 may include first layer 15 (for example, comprising thin staple fiber), the second layer 20 and one or more optional layers 25 (for example, supporting layer, meltblown layer), first layer 15 is in first layer (for example, modified the One layer) at least one surface on and/or it is internal there is material 55, as shown in Figure 3B.In certain embodiments, filter medium It may include first layer 15 (for example, comprising thin staple fiber), have the second layer of material (for example, surface at least one surface The modified second layer) and one or more optional layers 25 (for example, supporting layer, meltblown layer).In some cases, filtering is situated between Matter may include at least one surface and/or inside has the first layer 15 (for example, comprising thin staple fiber) of material, at least The second layer (for example, surface is modified the second layer) and one or more optional layers 25 on one surface with material.One In a little situations, filter medium may include at least one surface and/or it is internal there is material first layer 15 (for example, comprising Thin staple fiber), at least one surface and/or the internal second layer (for example, modified second layer) with material and extremely On a few surface and/or inside has one or more optional layers 25 (for example, modified layer) of material.In some embodiment party In case, each layer in filter medium can be modified layer.In certain embodiments, each fibrous layer in filter medium can be Modified layer.It in some embodiments, can be to change less equal than two layers (for example, two layers, a layer) in filter medium Property layer.As described herein, modified layer can only have two surfaces on the surface with the layer of material modification, the layer with material modification, Can only have and entire layer is modified with the inside or available material of the layer of material modification.

It, can be by least the one of one or more layers in some embodiments of the wherein filter medium for fluid separation Fluid to be separated is wetting in pairs for a surface and/or inter-modification.In some such embodiments, surface is soaked And/or the internal at least part droplet coalescence that can be used for making fluid to be separated, it is moved at subsequent layer so that drop has Out required size and/or enable coalescence drop (example is separated at the wetability part (for example, surface, inside) of layer Such as, pass through gravity).In some embodiments, one or more layers of surface can be modified to repel fluid to be separated. For example, repelling the conveying that surface can substantially stop the drop of fluid to be separated, so that the drop of certain size can be suppressed It flows through with the layer for repelling surface, and separates (for example, falling off) from filtering fluid.

In some embodiments, filter medium may include having wetting surface as described above or repelling surface at least One modified layer.In certain embodiments, filter medium may include with the modified layer for soaking surface and having repulsion surface Both modified layers.

It should be understood that the configuration of layer shown in figure is only example, and in other embodiments, including other of layer The filter medium of configuration is also possible.Although for example, in Fig. 1 to 3 with particular order show first layer and the second layer (and Optional third layer, the 4th layer etc.), but in other embodiments, optional third layer can be located at first layer and the second layer Between.In other embodiments, first layer can be between the second layer and optional third layer.In other embodiment In, one or more middle layers (such as one or more unmodified layers) may be present between the two layers.Other configurations It is possible.Furthermore, it is to be understood that as used herein, term " first " layer, " second " layer, " third " layer and " the 4th " layer are Refer to the different layers in medium, and is not meant to that the specific function relative to this layer is limited.Although for example, in some realities Applying in scheme " first " layer can be described as comprising thin staple fiber, but in other embodiments, " first " layer can not include Thin staple fiber.In addition, in some embodiments, other than layer shown in figure, extra play also may be present (for example, " Five " layers, " the 6th " layer or " the 7th " layer).For example, in some embodiments, filter medium or filter device may include up to About 20 layers.It should also be understood that in some embodiments, all components not shown in figure all need to exist.For example, one In a little embodiments, filter medium may not include third layer and/or modified layer.

As described herein, in some embodiments, the layer of filter medium may include the relatively small polymer of average diameter Staple fiber.In some embodiments, the average diameter of the thin polymer short fiber in layer may be less than or equal to about 11 microns, it is small In or equal to about 10 microns, less than or equal to about 8 microns, less than or equal to about 6 microns, less than or equal to about 4 microns, be less than or Equal to about 3 microns, less than or equal to about 2 microns, less than or equal to about 1 micron, less than or equal to about 0.8 micron, be less than or wait In about 0.5 micron, less than or equal to about 0.2 micron or less than or equal to about 0.1 micron.In some cases, thin in layer The avarage fiber diameter of polymer short fiber can greater than or equal to about 0.1 micron, greater than or equal to about 0.2 micron, be greater than or wait In about 0.5 micron, greater than or equal to about 0.8 micron, greater than or equal to about 1 micron or greater than or equal to about 3 microns.It is above-mentioned The combination of range is also possible.For example, in certain embodiments, the average diameter of polymer short fiber can be to be greater than Or be equal to about 0.1 micron and less than or equal to about 11 microns, greater than or equal to about 0.1 micron and less than or equal to about 3 microns, it is big In or be equal to about 0.1 micron and less than or equal to about 1 micron, it is greater than or equal to about 0.1 micron and micro- less than or equal to about 0.8 Rice or greater than or equal to about 0.1 micron and less than or equal to about 0.5 micron.In some embodiments, polymer short fiber Average diameter less than 1 micron.

In general, polymer short fiber is discontinuous fiber.That is, polymer short fiber be typically cut into (for example, by Long filament) or be formed as discontinuous discrete fibre with specific length or length range.In some embodiments, polymer is short The length of fiber may be less than or equal to about 20cm, less than or equal to about 10cm, less than or equal to about 5cm, less than or equal to about 10mm, less than or equal to about 6mm, less than or equal to about 5mm, less than or equal to about 3mm, less than or equal to about 2mm, be less than or wait In about 1mm, less than or equal to about 0.75mm, less than or equal to about 0.5mm, less than or equal to about 0.2mm, less than or equal to about 0.1mm, less than or equal to about 0.05mm, less than or equal to about 0.02mm.In some cases, the length of polymer short fiber can Greater than or equal to about 0.005mm, greater than or equal to about 0.01mm, greater than or equal to about 0.02mm, greater than or equal to about 0.05mm, Greater than or equal to about 0.1mm, greater than or equal to about 0.2mm, greater than or equal to about 0.5mm, greater than or equal to about 0.75mm, be greater than Or be equal to about 1mm, greater than or equal to about 5mm, greater than or equal to about 10mm, greater than or equal to about 5cm or greater than or equal to about 10cm.The combination of above range be it is possible (for example, greater than or equal to about 0.005mm and less than or equal to about 20cm, be greater than or Equal to about 0.01mm and less than or equal to about 10cm, greater than or equal to about 1mm and less than or equal to about 6mm).

In general, polymer short fiber is (for example, more than first polymer short fiber, more than second polymer short fiber, third More polymer short fibers, the 4th more polymer short fibers etc.) there can be any suitable composition.It can be used for being formed polymerization The non-limiting example of the material (for example, polymer) of object staple fiber include polyester (for example, polycaprolactone), cellulose acetate, Polymethyl methacrylate, polystyrene, polyaniline, polypropylene, polyamide, Nomex (for example, contraposition Nomex, Position Nomex), polyimides (for example, polyetherimide (PEI)), polyethylene, polyether-ketone, polyethylene terephthalate Ester, nylon, polyacrylic, polyvinyl alcohol, polyether sulfone, poly- (phenylate sulfone), polysulfones, polyacrylonitrile, gathers inclined difluoro second at polyolefin Alkene, polybutylene terephthalate (PBT), poly- (lactic acid), polyphenylene oxide, polycarbonate, polyurethane, polyethyleneimine, polyaziridine, Polypyrrole, zeins, polyimides, polyvinyl butyral, phenyl-yuban, organosilicon, polyethylene glycol and Its composition or copolymer (for example, block copolymer).Those of ordinary skill in the art will be readily selected hydrophobic fiber, Hydrophilic fibers or fiber with necessary intrinsic wetability.

Polymer short fiber can have any suitable configuration.For example, in some embodiments, polymer short fiber is Homofil, however, in other embodiments, polymer short fiber is multicomponent fibre.In some cases, it polymerize Object staple fiber can be curling.In other cases, polymer short fiber is non-crimping.Other configurations are also possible.

In some embodiments, the layer comprising thin polymer fiber may include the thin short fibre of relative high weight percentage Dimension.In some embodiments, such as the total weight based on the fiber in layer, the weight percent of the thin polymer short fiber in layer Than can greater than or equal to about 0.5 weight %, greater than or equal to about 1 weight %, greater than or equal to about 3 weight %, be greater than or equal to About 5 weight %, greater than or equal to about 8 weight %, greater than or equal to about 10 weight %, greater than or equal to about 15 weight %, be greater than Or be equal to about 20 weight %, greater than or equal to about 25 weight %, greater than or equal to about 30 weight %, greater than or equal to about 35 weights Amount %, greater than or equal to about 40 weight %, greater than or equal to about 45 weight %, greater than or equal to about 50 weight %, be greater than or wait In about 60 weight %, greater than or equal to about 70 weight %, greater than or equal to about 80 weight % or greater than or equal to about 90 weights Measure %.In some cases, such as the total weight based on the fiber in layer, the weight percent of the thin polymer short fiber in layer May be less than or equal to about 100 weight %, less than or equal to about 99 weight %, less than or equal to about 98 weight %, be less than or equal to About 96 weight %, less than or equal to about 92 weight %, less than or equal to about 90 weight %, less than or equal to about 85 weight %, small In or be equal to about 80 weight %, less than or equal to about 75 weight %, less than or equal to about 70 weight %, less than or equal to about 60 weights Amount %, less than or equal to about 55 weight %, less than or equal to about 50 weight %, less than or equal to about 45 weight %, be less than or wait In about 40 weight %, less than or equal to about 35 weight %, less than or equal to about 30 weight %, less than or equal to about 25 weight %, Less than or equal to about 20 weight %, less than or equal to about 15 weight %, less than or equal to about 10 weight % or be less than or equal to About 5 weight %.The combination of above range be it is possible (for example, greater than or equal to about 0.5% and less than or equal to about 100%, it is big In or equal to about 1% and less than or equal to about 100%, greater than or equal to about 50% and less than or equal to about 100%, be greater than or wait In about 70% and less than or equal to about 100%, greater than or equal to about 90% and less than or equal to about 100%).In some embodiment party In case, the weight percent of the thin polymer short fiber in layer can be 100%.In some embodiments, above-mentioned weight percent Than the weight of total dry solid based on layer (including any resin).

In some embodiments, the layer comprising thin polymer short fiber may include other fibers (for example, in addition to carefully gathering Close the fiber except object staple fiber), as described in greater detail below.

In some embodiments, the layer comprising thin polymer short fiber can be relatively thin.In some such embodiments In, every other factor is identical, and such layer is identical as thickness or bigger but includes continuous fiber rather than thin polymer short fiber Similar layer compare, can have relatively high than dust containing capacity and/or low pressure drop.

In some embodiments, the thickness of the layer comprising thin polymer short fiber may be less than or equal to about 1mm, be less than or Equal to about 0.9mm, be less than about 0.8mm, less than or equal to about 0.7mm, less than or equal to about 0.6mm, less than or equal to about 0.5mm, less than or equal to about 0.4mm, less than or equal to about 0.3mm, less than or equal to about 0.2mm, less than or equal to about 0.1mm, less than or equal to about 0.09mm or less than or equal to about 0.08mm.In some cases, the thickness of filter medium can Greater than or equal to about 0.03mm, greater than or equal to about 0.04mm, greater than or equal to about 0.05mm, greater than or equal to about 0.06mm, Greater than or equal to about 0.07mm, greater than or equal to about 0.08mm, greater than or equal to about 0.09mm, greater than or equal to about 0.1mm, big In or be equal to about 0.2mm, greater than or equal to about 0.3mm, greater than or equal to about 0.4mm, greater than or equal to about 0.5mm or big In or equal to 0.6mm.The combination of above range be it is possible (for example, greater than or equal to about 0.03mm and less than or equal to about 1mm, greater than or equal to about 0.05mm and less than or equal to about 1mm, greater than or equal to about 0.03mm and less than or equal to about 0.2mm, greater than or equal to about 0.05mm and less than or equal to about 0.2mm).The other values of the thickness of filter medium are possible. Thickness can be in 2N/cm²It is lower to be determined according to standard ISO 534 (2011).

In some embodiments, the weight of determining of the layer comprising thin polymer short fiber can be greater than or equal to about 0.5g/m², it is big In or equal to about 1g/m², greater than or equal to about 2g/m², greater than or equal to about 5g/m², greater than or equal to about 10g/m², be greater than or Equal to about 20g/m², greater than or equal to about 30g/m², greater than or equal to about 40g/m², greater than or equal to about 50g/m², be greater than or wait In about 60g/m², greater than or equal to about 70g/m², greater than or equal to about 80g/m²Or greater than or equal to about 90g/m².Some In the case of, the fixed of filter medium may be less than or equal to about 100g/m again², less than or equal to about 90g/m², less than or equal to about 80g/ m², less than or equal to about 70g/m², less than or equal to about 60g/m², less than or equal to about 50g/m², less than or equal to about 40g/m²、 Less than or equal to about 30g/m², less than or equal to about 20g/m², less than or equal to about 10g/m², less than or equal to about 5g/m², it is small In or equal to about 2g/m²Or less than or equal to about 1g/m².The combination of above range be it is possible (for example, greater than or equal to about 0.5g/m²And less than or equal to about 100g/m², greater than or equal to about 0.5g/m²And less than or equal to about 50g/m²).Surely its heavy His value is possible.Determining weight can determine according to standard ISO 536 (2012).

Mean flow pore size can be selected as needed.For example, in some embodiments, including thin polymer short fiber Layer mean flow pore size can greater than or equal to about 0.05 micron, greater than or equal to about 0.1 micron, it is micro- greater than or equal to about 0.15 Rice, greater than or equal to about 0.2 micron, greater than or equal to about 0.5 micron, greater than or equal to about 1 micron, it is micro- greater than or equal to about 10 Rice, greater than or equal to about 25 microns, greater than or equal to about 50 microns, greater than or equal to about 75 microns, it is micro- greater than or equal to about 100 Rice or greater than or equal to about 125 microns.In some cases, the mean flow pore size of the layer comprising thin polymer short fiber May be less than or equal to about 150 microns, less than or equal to about 125 microns, less than or equal to about 100 microns, less than or equal to about 75 Micron, less than or equal to about 50 microns, less than or equal to about 25 microns, less than or equal to about 10 microns or be less than or equal to About 1 micron.The combination of above range is also possible (for example, greater than or equal to about 0.05 micron and micro- less than or equal to about 150 Rice, greater than or equal to about 0.1 micron and less than or equal to about 150 microns, greater than or equal to about 0.15 micron and be less than or equal to About 100 microns, greater than or equal to about 0.2 micron and less than or equal to about 100 microns, greater than or equal to about 1 micron and be less than or Equal to about 150 microns).The other values of mean flow pore size are also possible.Mean flow pore size can be according to standard ASTM F316 (2003) it determines.

In some embodiments, the layer as described herein comprising thin polymer short fiber and/or including such layer Filter medium can have the particular kind of relationship between mean flow pore size and permeability.Pass between mean flow pore size and permeability System is represented by [mean flow pore size (μm)/(permeability (CFM))^0.5], it is also referred to as permeability pore size index herein (Perm.Pore Index).It in other words, can be by the mean flow pore size of layer or filter medium correspondingly divided by the layer or the mistake The square root of the permeability of filter medium.In some embodiments, the layer as described herein comprising thin polymer short fiber and/or [mean flow pore size (μm)/(permeability (CFM)) of filter medium including such layer^0.5] value can be about 0.5 to about 6.0. In some embodiments, [mean flow pore size (μm)/(permeability (CFM)) of layer and/or filter medium^0.5] value be less than or Equal to about 6, less than or equal to about 5, less than or equal to about 4, less than or equal to about 3, less than or equal to about 2.5, be less than or equal to About 2, less than or equal to about 1.8, less than or equal to about 1.6, less than or equal to about 1.5, less than or equal to about 1.4, be less than or wait In about 1.2, less than or equal to about 1.0, less than or equal to about 0.9, less than or equal to about 0.8, less than or equal to about 0.7 or Less than or equal to about 0.6.In some embodiments, [the mean flow pore size (μm)/(permeability of layer and/or filter medium (CFM))^0.5] value greater than or equal to about 0.5, greater than or equal to about 0.6, greater than or equal to about 0.8, greater than or equal to about 1.0, it is big In or be equal to about 1.2, greater than or equal to about 1.5, greater than or equal to about 2.0, greater than or equal to about 3.0, greater than or equal to about 4.0 or greater than or equal to about 5.0.The combination of above range is also possible (for example, [mean flow pore size (μm)/(infiltration Rate (CFM))^0.5] value is greater than about 0.5 and less than or equal to about 3.0).Other values are also possible.

As described herein, filter medium may include layer and the second layer comprising thin polymer short fiber.In some embodiment party In case, the second layer may include relatively crude fiber.For example, in some embodiments, the average diameter of the fiber in the second layer Can greater than or equal to about 1 micron, greater than or equal to about 2 microns, greater than or equal to about 3 microns, greater than or equal to about 4 microns, it is big In or equal to about 5 microns, greater than or equal to about 6 microns, greater than or equal to about 7 microns, greater than or equal to about 8 microns, be greater than or Equal to about 9 microns, greater than or equal to about 10 microns, greater than or equal to about 12 microns, greater than or equal to about 15 microns, be greater than or wait In about 20 microns, greater than or equal to about 30 microns, greater than or equal to about 40 microns, greater than or equal to about 50 microns, be greater than or wait In about 60 microns, greater than or equal to about 70 microns, greater than or equal to about 80 microns or greater than or equal to about 90 microns.One In a little situations, the average diameter of the fiber in the second layer may be less than or equal to about 100 microns, less than or equal to about 90 microns, it is small In or be equal to about 80 microns, less than or equal to about 70 microns, less than or equal to about 60 microns, less than or equal to about 50 microns, it is small In or be equal to about 40 microns, less than or equal to about 30 microns, less than or equal to about 20 microns, less than or equal to about 18 microns, it is small In or equal to about 15 microns, less than or equal to about 12 microns, less than or equal to about 10 microns, less than or equal to about 9 microns, be less than Or equal to about 8 microns, less than or equal to about 7 microns, less than or equal to about 6 microns, less than or equal to about 5 microns or be less than Or it is equal to about 4 microns.The combination of above range is also possible (for example, greater than or equal to about 4 microns and less than or equal to about 20 Micron, greater than or equal to about 4 microns and less than or equal to about 15 microns).In some embodiments, fiber in the second layer Average diameter be greater than about 1 micron and less than or equal to about 4 microns (for example, greater than about 1 micron and less than or equal to about 2 microns, it is big In or be equal to about 2 microns and less than or equal to about 3 microns, greater than or equal to about 3 microns and less than or equal to about 4 microns).It is average The other values of fibre diameter are also possible.

In some embodiments, the second layer can be wet laid layer.In other cases, the second layer can be non-wet process At stratum reticulare.The non-limiting example of suitable non-wet laid layer include meltblown layer, airlaid layer, spunbond layer, mesh layer, Power spins layer, hydroentangled layer, needle thorn layer, carded layer or electrostatic spinning layer, power and spins layer.In certain embodiments, the second layer can be single Layer or including a plurality of sublayers (for example, 2 sublayers, 3 sublayers, 4 sublayers, 5 sublayers, 6 sublayers, 7 sublayers, 8 Sublayer, 9 sublayers, 10 sublayers).In some such embodiments, the second layer can be composite layer.

As described herein, filter medium may include comprising the layer of thin polymer short fiber, the second layer and one or more A optional layer.In some embodiments, one or more optional layers (for example, third layer, the 4th layer) can be used as filtering Jie The support of one or more layers and/or entire filter medium of matter.For example, filter medium is gone back in addition to first layer and the second layer It may include supporting layer.Supporting layer can help to for example, by during filtering improve filter medium one or more layers and/ Or the mechanical integrity of entire filter keeps or improves certain filtering features (for example, efficiency, dust containing capacity).For example, one In a embodiment, the filter medium of pleating may include supporting layer (for example, plastic web of the metal mesh of extension, extrusion), The supporting layer facilitates the construction that pleating is kept during filtering, this is at least partially because the increased Gurley of supporting layer offer is rigid Degree.Supporting layer can help to keep given filter medium shape during filtering and/or provide resistance fluid for filter medium The support of stream.For example, in some embodiments, supporting layer as described herein can mention during filtering for the filter medium of pleating For enough rigidity, so that most of or essentially all pleat keeps its relatively uniform separation.It is basic with not supporting layer Identical filter medium is compared, and keeps filter medium shape that can realize beneficial fluid flowing by filter medium during filtering Mode (for example, filter medium is relatively evenly exposed to filtering fluid), and therefore realize efficiency, dust containing capacity and the moisture of raising From efficiency.

In some embodiments, supporting layer (for example, third layer) can be mesh (for example, synthesis shape object).Certain In embodiment, mesh can have Gurley rigidity more higher than certain weavings and/or non-woven layer, and can be particularly suitable The support of resistance fluid stream is provided in the shape for keeping filter medium during filtering and/or for filter medium.Workable net The non-limiting example of shape object includes metallic mesh (for example, line mesh, stainless steel mesh) and synthetic mesh object (example Such as, plastic web, polymer mesh).In some embodiments, mesh can for weaving layer, braiding layer, welding layer, Extension layer, photochemical etching layer or electroformed layer, various meshes may originate from metal and/or plastics.In general, mesh can be loose The fabric of weaving or braiding, the hole with relatively great amount of tight spacing.

In some embodiments, filter medium may also include in addition to first layer and the second layer be designed to improve one or The layer (for example, filter layer) (for example, meltblown layer) of more filtering features.Filter layer can for example improve filter medium service life, Water separative efficiency and/or dust containing capacity.In some embodiments, filter layer may be designed to improve water separative efficiency.It is some this In the embodiment of sample, filter layer can be modified layer as described herein.However, in other embodiments, filter layer is not For modified layer.In certain embodiments, filter layer can be meltblown layer.For example, filter layer can be such meltblown layer: its fixed weight Greater than or equal to about 3g/m²And less than or equal to about 400g/m²(for example, greater than or equal to about 5g/m²And less than or equal to about 300g/m², greater than or equal to about 25g/m²And less than or equal to about 300g/m²) and air penetrability less than or equal to about 800CFM (example Such as, less than or equal to about 500CFM) and greater than or equal to about 5CFM (for example, greater than or equal to about 8CFM).

In some embodiments, the layer comprising thin polymer short fiber can be used for assigning filter medium high fluid separation Efficiency.In some such embodiments, polymer short fiber layer can be designed to have specific wetability and/or with filtering The different wetability of one or more layers (for example, second layer) in medium.Thin polymer short fiber in optional layer Composition allows to generate relative to particular fluid using the intrinsic wetting characteristics of thin polymer short fiber (for example, to be separated Fluid) expectation wetability.For example, correspondingly shape can be carried out using hydrophobic thin polymer short fiber or hydrophilic thin polymer short fiber At hydrophobic layer or hydrophilic layer.In another example, can be used has the thin polymer of different wetting short relative to particular fluid The blend of fiber forms the layer with specific wetability.

In some embodiments, it can be used one or more modified layers (for example, one comprising thin polymer short fiber A or more layer, the second layer, third layer, optional layer) assign filter medium high fluid separative efficiency.In some cases, It can be by having the stream that separate strata knot and/or repulsion from filtering fluid (for example, hydraulic fluid, fuel, water, air) The surface of body (for example, water, hydraulic fluid, oil) is modified to realize increased fluid separation.In other embodiments, surface Modification makes layer simply by fluid to be separated, which is separated in downstream layer.In some cases, it uses Material, which is modified the surface of layer to assign, is used alone the wetting characteristics that fiber is difficult to realize or cannot achieve.For example, In some embodiments, treatment conditions may limit the ability for being formed as fiber with relatively high hydrophobic material, from And exclusive use fiber is prevented to form relatively high hydrophobic surface.However, be modified by the surface to existing web, it can The hydrophobic surface for being suitable for hydrophobicity is provided using various hydrophobic materials.Similarly, certain processing and/or application limitation can Can limitation with fibers form use certain water wetted materials, however, the surface of existing web is modified can permit it is certain Water wetted material be used to assign surface desired hydrophily.

In some such embodiments, one or more modified layers can be designed to have specific wetability and/ Or the wetability different from one or more layers (for example, second layer) in filter medium.In some embodiments, including It is designed to that the filter medium for improving two or more layers of fluid separative efficiency (for example, fuel-water separative efficiency) may include At least two modified layers.In certain embodiments, the filter medium including two or more modified layers with have one or There is no the filter medium of modified layer to compare the fluid separative efficiency that there can be raising.In some embodiments, it including is designed to The filter medium for improving two or more layers of fluid separative efficiency (for example, fuel-water separative efficiency) may include at least one A modified layer (for example, two or more modified layers) and at least one substantially hydrophilic or hydrophobic layer.In certain embodiment party In case, filter medium including at least one modified layer and at least one substantially hydrophilic or hydrophobic layer with there is one or do not have There is the filter medium of modified layer to compare the fluid separative efficiency that there can be raising.

As used herein, term " wetting " and " wetability " can refer to fluid and surface interacts so that fluid is relative to table Ability of the contact angle in face less than 90 degree.Therefore, term " repulsion " and " repellency " can refer to fluid and surface interact so that Fluid is greater than or equal to 90 degree of ability relative to the contact angle on surface.

In general, the wetability of one or more layers (for example, layer comprising thin polymer short fiber) may be selected so that should The fluid (for example, water, oil) that layer repels or coalescence will be separated from filtering fluid (for example, fuel, hydraulic fluid, water, air).? Under some cases, fluid to be separated can be repelled or be coalesced in the surface of layer (for example, layer comprising thin polymer short fiber).Another Under some cases, repulsion and coalescence can occur in the inside of layer (for example, layer comprising thin polymer short fiber).In some implementations In scheme, layer (for example, layer comprising thin polymer short fiber) can be designed to repel fluid to be separated.In such situation Under, layer (for example, layer comprising thin polymer short fiber) can substantially stop the conveying of the drop of fluid to be separated, so that can Inhibit the drop of certain size to flow through such exclusion layer and separates (for example, falling off) from filtering fluid.In some embodiment party In case, layer (for example, layer comprising thin polymer short fiber) can be designed to be to soak and coalesce to want to fluid to be separated Isolated fluid.In this case, layer (for example, layer comprising thin polymer short fiber) can be used for making fluid to be separated At least part droplet coalescence so that drop have at subsequent layer remove needed for size and/or make coalescence liquid Drop can separate (for example, passing through gravity) at the layer (for example, layer comprising thin polymer short fiber).

In some embodiments, filter medium may include cohesiveness or repellency first layer as described above (for example, packet Layer containing thin polymer short fiber) and relative to particular fluid have with first layer (for example, including thin polymer short fiber Layer) different wetability the second layer.It can be by such medium designs at the liquid for coalescing and repelling fluid to be separated simultaneously Drop.In certain embodiments, first layer (for example, layer comprising thin polymer short fiber) can repel fluid to be separated, and The second layer can coalesce fluid to be separated.For example, being designed to the separation hydrophylic fluids from filtering fluid (for example, hydrophobic liquid) Filter medium may include the hydrophobic layer comprising thin polymer short fiber in the upstream of the hydrophilic second layer.Include the short fibre of thin polymer The upstream hydrophobic layer of dimension can be used for repelling and removing hydrophilic drop (for example, by falling off), and the hydrophilic second layer in downstream is available In coalesce and remove (for example, passing through gravity) filtering fluid at least part remnants hydrophylic fluids.In some cases, compared with Big hydrophylic fluids drop falls off by the inclusion of the hydrophobic layer of thin polymer short fiber in upstream, and remaining hydrophylic fluids liquid It drips and is coalesced at the hydrophilic second layer to form the larger drop removed by gravity.

In another example, it is designed to the filter medium of the separation hydrophylic fluids from filtering fluid (for example, hydrophobic liquid) It may include the hydrophilic second layer in the upstream of the hydrophobic layer comprising thin polymer short fiber.Upstream hydrophilic layer can be used for coalescing and moving (for example, passing through gravity) hydrophilic drop out, and include thin polymer short fiber downstream hydrophobic layer can be used for removing filtering stream At least part residue hydrophylic fluids in body.In some cases, hydrophylic fluids drop coalesces at the hydrophilic second layer with shape At the larger drop for passing through gravity or being removed in downstream by the inclusion of the hydrophobic layer of thin polymer short fiber.In other embodiment party In case, the layer comprising thin polymer short fiber can coalesce fluid to be separated, and the second layer can repel fluid to be separated.One In a little such embodiments, the layer comprising thin staple fiber is the hydrophilic layer in examples detailed above, and the second layer is in examples detailed above Hydrophobic layer.

In some embodiments, filter medium may include comprising thin polymer short fiber first layer and relative to specific Fluid has the second layer of the wetability similar or essentially identical to first layer.In some such embodiments, filtering is situated between Fluid to be separated can be repelled or be coalesced to matter.For example, being designed to that the filter medium for removing hydrophylic fluids from filtering fluid can wrap Include hydrophobic layer and hydrophobic second layer comprising thin polymer short fiber.Hydrophobic layer comprising thin polymer short fiber can be hydrophobic Two layers of upstream or downstream.In certain embodiments, downstream layer can be used for repelling the stream for not repelled and/or being removed by upstream layer Body fluid drips and it is made to fall off.For example, upstream layer can be designed to repel and/or remove relatively large drop, and can be by downstream Layer is designed to repel the smaller droplet by upstream layer and it is made to fall off.In another example, it is designed to move from filtering fluid The filter medium of hydrophylic fluids may include hydrophilic layer and the hydrophilic second layer comprising thin polymer short fiber out.Include thin polymer The hydrophilic layer of staple fiber can be in the upstream or downstream of the hydrophilic second layer.In certain embodiments, downstream layer can be used for coalesce and/ Or remove the fluid drop for not coalesced and/or being removed by upstream layer.For example, upstream layer can be designed to coalesce and/or remove phase To big drop, and downstream layer can be designed to coalesce and/or be shifted out through the smaller droplet of upstream layer.

In some embodiments, one or more layers (for example, layer comprising thin polymer short fiber) can be used for mentioning Height includes the filter medium of the layer comprising thin polymer short fiber and/or the ensemble average fluid separative efficiency of filter device.? In some embodiments, mean flow (for example, fuel-water) separative efficiency of filter medium can be about 20% to about 99.99% Or higher (for example, about 25% to about 99.99%, about 30% to about 99.99%, about 60% to about 99.99%).For example, at certain In a little embodiments, the mean flow separative efficiency of filter medium can at least about 20%, at least about 25%, at least about 30%, At least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, At least about 98%, at least about 99% or at least about 99.5%.In some cases, the mean flow separative efficiency of filter medium May be less than or equal to about 99.99%, less than or equal to about 99.95%, less than or equal to about 99.9%, less than or equal to about 99%, less than or equal to about 98%, less than or equal to about 95%, less than or equal to about 90%, less than or equal to about 80%, be less than Or equal to about 70%, less than or equal to about 60%, less than or equal to about 50%, less than or equal to about 40% or be less than or wait In about 30%.The combination of above range is possible (for example, at least about 60% and less than or equal to about 99.99%).Other models It is also possible for enclosing.

In certain embodiments, initial fluid separative efficiency can at least about 20%, at least about 25%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, at least about 98%, at least about 99%, at least about 99.9% or at least about 99.99%.In some cases, initial fluid Separative efficiency may be less than or equal to about 99.99%, less than or equal to about 99.9%, less than or equal to about 99%, be less than or equal to About 98% or less than or equal to about 95%.The combination of above range is possible (for example, at least about 60% and being less than or waiting In about 99.99%).Other ranges are also possible.

As used herein, mean flow separative efficiency and initial fluid separative efficiency are measured using SAEJ1488 test. The test includes making fuel (ultra-low-sulphur diesel) sample with controlled water content (2500ppm) with 0.069cm/ seconds by pump Face velocity passes through medium.Water and milk is melted into small droplet and it is made to challenge medium.Water coalesce or fall off either both, and It collects in the bottom of shell.The aqueous of sample is measured in both upstream and downstreams of medium by Karl Fischer titration Amount.Efficiency is the amount of the water removed from fuel-water mixture.Fluid separative efficiency is calculated according to (1-C/2500) * 100, Middle C is the water concentration in downstream.Starting efficiency calculates for first 10 minutes test, at the end of average efficiency is calculated as 150 minutes The average value of efficiency.In order to measure mean flow separative efficiency as described herein, being situated between for the 10th minute after test starts The upstream and downstream of matter carries out the first time measurement to sample.Then, every 20 minutes downstreams in medium carry out the survey to sample Amount.

In some embodiments, multiple layers of medium described herein can be used to pass through multiple stages including filter medium (for example, multiple alternate hydrophobic and hydrophilic stages), and/or by controlling each layer and/or the aperture in each stage, fixed weight, thickness And/or surface chemical property realizes higher mean flow separative efficiency and initial fluid separative efficiency.

As described above, in some embodiments, first layer (for example, layer comprising thin polymer short fiber) is than filtering The second layer in medium is more hydrophobic.In some such embodiments, first layer is (for example, include thin polymer short fiber Layer) surface on water contact angle can be greater than or equal to about 30 degree and less than or equal to about 165 degree (for example, being greater than or equal to About 35 degree and less than or equal to about 165 or other ranges as described herein).Water contact angle on the surface of the second layer can be big In or be equal to about 0 degree and less than or equal to about 125 degree (or other ranges as described herein), on condition that first layer (for example, wrapping Layer containing thin polymer short fiber) water contact angle be greater than the second layer water contact angle.

In general, the contact angle of first layer (for example, layer comprising thin polymer short fiber) can be selected as needed.Some In embodiment, the water contact angle on the surface of first layer (for example, layer comprising thin polymer short fiber) can be greater than or equal to About 30 degree, greater than or equal to about 35 degree, greater than or equal to about 40 degree, greater than or equal to about 50 degree, greater than or equal to about 60 degree, it is big In or equal to about 70 degree, greater than or equal to about 60 degree, greater than 90 degree, more than or equal to 100 degree, more than or equal to 105 degree, be greater than Or be equal to 110 degree, be greater than or equal to 115 degree, be greater than or equal to 120 degree, more than or equal to 125 degree, more than or equal to 130 degree, More than or equal to 135 degree, more than or equal to 145 degree, more than or equal to 150 degree, more than or equal to 155 degree or be greater than or wait In 160 degree.In some cases, water contact angle less than or equal to about 165 degree, less than or equal to about 160 degree, less than or equal to about 150 degree, less than or equal to about 140 degree, less than or equal to about 130 degree, less than or equal to about 120 degree, less than or equal to about 110 Degree, less than or equal to about 100 degree, less than or equal to about 90 degree, less than or equal to about 80 degree, less than or equal to about 70 degree, be less than Or be equal to about 60 degree, less than or equal to about 50 degree, less than or equal to about 40 degree or less than or equal to about 35 degree.Above range Combination be also possible (for example, greater than or equal to about 30 degree and less than or equal to about 165 degree).Standard can be used in water contact angle ASTM D5946 (2009) measurement.Contact angle be when drop stop on the surface of the substrate when, at three phase point substrate surface with draw The angle between the tangent line tangent with water drops surface is made.Contact angle meter can be used or angular instrument carries out the measurement.

In some embodiments, the water contact angle on the surface of the second layer less than or equal to about 125 degree, be less than or equal to About 120 degree, less than or equal to about 110 degree, less than 100 degree, less than or equal to about 90 degree, less than or equal to about 80 degree, be less than or Equal to about 70 degree, less than or equal to about 60 degree, less than or equal to about 50 degree, less than or equal to about 40 degree, less than or equal to about 30 Degree, less than or equal to about 25 degree, less than or equal to about 20 degree or less than or equal to about 15 degree.In some cases, water contacts Angle greater than or equal to about 0 degree, greater than or equal to about 5 degree, greater than or equal to about 10 degree, greater than or equal to about 20 degree, be greater than or wait In about 30 degree, greater than or equal to about 40 degree, greater than or equal to about 50 degree, greater than or equal to about 60 degree, greater than or equal to about 70 degree, Greater than 80 degree, be greater than or equal to 90 degree, be greater than or equal to 100 degree, more than or equal to 110 degree, more than or equal to 115 degree or More than or equal to 120 degree.The combination of above range is also possible.In certain embodiments, the fiber (example being present in layer Such as, polymer short fiber) by having the material of the contact angle (for example, water contact angle) in one or more ranges to be formed. As used herein, the contact angle of material according to standard ASTM D5946 (2009) of the fiber that the material is formed by being only made Plain film (flatsheet) on measurement contact angle determine that the avarage fiber diameter of fiber is 0.8 ± 0.5 micron and this is flat The weight of determining of piece is 50g/m²And MFP is 1.5 microns to 6.5 microns.

In some embodiments, the water contact angle of material described herein or layer (for example, modified layer, unmodified layer) (for example, being used to form the polymer short fiber such as material of more than first polymer short fiber and/or more than second polymer short fiber The water contact angle of material) can greater than or equal to about 30 degree, greater than or equal to about 35 degree, greater than or equal to about 40 degree, be greater than or equal to About 50 degree, greater than or equal to about 60 degree, greater than or equal to about 70 degree, greater than or equal to about 80 degree, greater than 90 degree, be greater than or equal to 100 degree, more than or equal to 105 degree, more than or equal to 110 degree, more than or equal to 115 degree, more than or equal to 120 degree, be greater than or Equal to 125 degree, be greater than or equal to 130 degree, be greater than or equal to 135 degree, be greater than or equal to 145 degree, more than or equal to 150 degree, greatly In or be equal to 155 degree or more than or equal to 160 degree.In some cases, water contact angle less than or equal to about 165 degree, be less than Or equal to about 160 degree, less than or equal to about 150 degree, less than or equal to about 140 degree, less than or equal to about 130 degree, be less than or wait In about 120 degree, less than or equal to about 110 degree, less than or equal to about 100 degree, less than or equal to about 90 degree, less than or equal to about 80 Degree, less than or equal to about 70 degree, less than or equal to about 60 degree, less than or equal to about 50 degree, it is less than or equal to about 40 degree or small In or equal to about 35 degree.The combination of above range be also it is possible (for example, greater than or equal to about 30 degree and less than or equal to about 165 degree).

It should be understood that contact angle as described herein is related to modified layer and unmodified layer.

In certain embodiments, polymer short fiber (more than first polymerization of layer (for example, first layer) as described herein Object staple fiber and/or more than second polymer short fiber) it is formed by the hydrophobicity material bigger than the hydrophobicity of the second layer.At this In the embodiment of sample, the water contact angle of the material of polymer short fiber is used to form (such as above-mentioned use material shape as At fiber plain film measured by) be greater than the water contact angle that such as measures on the surface of the second layer.

In some embodiments as described herein, layer includes more than first polymer short fiber formed by water wetted material (for example, the water contact angle for being used to form the material of first polymer staple fiber is (such as above-mentioned using the fibre being of a material that The plain film measurement of dimension) less than 90 degree).In some embodiments, layer includes more than second polymer short fiber.In certain realities It applies in scheme, more than second polymer short fiber is formed by hydrophobic material (for example, being used to form more than second polymer short fiber Material water contact angle (as it is above-mentioned measured using the plain film of fiber being of a material that) be at least 90 degree).? In some embodiments, layer includes by less hydrophobic material compared with the material for being used to form more than second polymer short fiber More than first polymer short fiber formed is (for example, be used to form the water contact angle of the material of more than first polymer short fiber (as the above-mentioned plain film using the fiber being of a material that measures) is less than being used to form second polymer staple fiber The contact angle (as the above-mentioned plain film using the fiber being of a material that measures) of material).Other configurations are also possible 's.

It should also be understood that the inherently phase relative to particular fluid can be replaced with modified layer for the embodiment above Hope wetting characteristics and without the layer of modified (for example, surface is modified).For example, in certain embodiments, having such as this paper institute The layer (for example, first layer) for the modified surface stated can have the hydrophobicity bigger than the hydrophobicity of the second layer.

In some embodiments, can have relatively high fluid separative efficiency includes comprising thin polymer short fiber The entire filter medium of layer can also have relatively high dust containing capacity.Dust containing capacity can be to be greater than or be equal to about 10g/m², be greater than Or it is equal to about 20g/m², greater than or equal to about 50g/m², greater than or equal to about 100g/m², greater than or equal to about 150g/m², be greater than Or it is equal to about 200g/m², greater than or equal to about 250g/m², greater than or equal to about 300g/m², greater than or equal to about 350g/m², it is big In or equal to about 300g/m², greater than or equal to about 350g/m², greater than or equal to about 400g/m²Or greater than or equal to about 450g/m².In some cases, dust containing capacity may be less than or equal to about 600g/m², less than or equal to about 550g/m², be less than or wait In about 500g/m², less than or equal to about 450g/m², less than or equal to about 400g/m², less than or equal to about 350g/m², be less than or Equal to about 300g/m², less than or equal to about 250g/m², less than or equal to about 200g/m², less than or equal to about 150g/m², be less than Or it is equal to about 100g/m², less than or equal to about 50g/m², less than or equal to about 25g/m²Or less than or equal to about 10g/m²。 The combination of above range is possible (for example, greater than or equal to about 10g/m²And less than or equal to about 350g/m², be greater than or equal to About 20g/m²And less than or equal to about 300g/m²).The other values of DHC are possible.Dust containing capacity can be used ISO 19438 true It is fixed.

In some embodiments, can be greater than than dust containing capacity (medium/layer dust containing capacity is divided by medium/layer thickness) or Equal to about 50g/m²/ mm, greater than or equal to about 75g/m²/ mm, greater than or equal to about 90g/m²/ mm, greater than or equal to about 100g/ m²/ mm, greater than or equal to about 200g/m²/ mm, greater than or equal to about 300g/m²/ mm, greater than or equal to about 500g/m²It is/mm, big In or equal to about 700g/m²/ mm or greater than or equal to about 900g/m²/mm.In some cases, be smaller than than dust containing capacity or Equal to about 1000g/m²/ mm, less than or equal to about 900g/m²/ mm, less than or equal to about 800g/m²/ mm, less than or equal to about 700g/m²/ mm, less than or equal to about 600g/m²/ mm, less than or equal to about 500g/m²/ mm, less than or equal to about 400g/m²/ Mm, less than or equal to about 300g/m²/ mm or less than or equal to about 100g/m²/mm.The combination of above range is possible (example Such as, greater than or equal to about 50g/m²/ mm and less than or equal to about 1000g/m²/ mm, greater than or equal to about 90g/m²/ mm and it is less than Or it is equal to about 500g/m²/mm).It is possible than the other values of DHC.

As described herein, in some embodiments, layer can be hydrophilic.As used herein, term " hydrophilic " is Refer to material of the water contact angle less than 90 degree.Therefore, " hydrophilic layer " can refer to layer of the water contact angle on the surface of the layers less than 90 degree. In some embodiments, layer can be hydrophilic so that water contact angle less than 90 degree, less than or equal to about 80 degree, be less than or Equal to about 75 degree, less than or equal to about 70 degree, less than or equal to about 65 degree, less than or equal to about 60 degree, less than or equal to about 55 Degree, less than or equal to about 50 degree, less than or equal to about 45 degree, less than or equal to about 40 degree, less than or equal to about 35 degree, be less than or Equal to about 30 degree, less than or equal to about 25 degree, less than or equal to about 20 degree or less than or equal to about 15 degree.In some implementations In scheme, water contact angle greater than or equal to about 0 degree, greater than or equal to about 5 degree, greater than or equal to about 10 degree, greater than or equal to about 15 degree, greater than or equal to about 20 degree, greater than or equal to about 25 degree, greater than or equal to about 35 degree, greater than or equal to about 45 degree or Greater than or equal to about 60 degree.The combination of above range be also it is possible (for example, greater than or equal to about 0 degree and less than 90 degree, be greater than Or be equal to about 0 degree and be less than about 60 degree).

As described herein, in some embodiments, layer can be hydrophobic.As used herein, term " hydrophobic " is Refer to that water contact angle is greater than or equal to the material of 90 degree (for example, be greater than or equal to 120 degree, be greater than or equal to 150 degree).Therefore, it " dredges Water layer " can refer to the layer that the water contact angle on the surface of layer is greater than or equal to 90 degree.It in some embodiments, can be modified by surface At hydrophobic so that water contact angle be greater than or equal to 90 degree, more than or equal to 100 degree, more than or equal to 105 degree, be greater than or wait In 110 degree, more than or equal to 115 degree, more than or equal to 120 degree, more than or equal to 125 degree, more than or equal to 130 degree, be greater than Or it is equal to 135 degree, is greater than or equal to 145 degree, is greater than or equal to 150 degree, being greater than or equal to 155 degree or more than or equal to 160 Degree.In some such embodiments, the contact angle on surface can be greater than or equal to about 150 degree.In some cases, water contacts Angle less than or equal to about 180 degree, less than or equal to about 175 degree, less than or equal to about 165 degree, less than or equal to about 150 degree, it is small In or be equal to about 135 degree, less than or equal to about 120 degree or less than or equal to about 105 degree.The combination of above range is also can (for example, be greater than or equal to 90 degree and be less than about 180 degree, greater than or equal to about 105 degree and less than about 180 degree) of energy.

In some embodiments, the layer comprising thin polymer short fiber can be used for assigning entire filter medium relatively high Primary particles efficiency and/or average grain efficiency.For example, in some embodiments, the starting efficiency of entire filter medium can Greater than or equal to about 50%, greater than or equal to about 60%, greater than or equal to about 70%, greater than or equal to about 80%, be greater than or wait In about 90%, greater than or equal to about 95%, greater than or equal to about 96%, greater than or equal to about 97%, greater than or equal to about 98%, Greater than or equal to about 99% or greater than or equal to about 99.9%, greater than or equal to about 99.99% or be about 100%.? Under some cases, the starting efficiency of entire filter medium may be less than or equal to about 100%, less than or equal to about 99.99%, be less than Or be equal to about 98%, less than or equal to about 97%, less than or equal to about 96%, less than or equal to about 90%, less than or equal to about 80%, less than or equal to about 70% or less than or equal to about 60%.The combination of above range is also possible (for example, being greater than Or be equal to about 50% and less than or equal to about 99.99%, greater than or equal to about 60% and less than or equal to about 99.99%).Filtering The other values of the starting efficiency of medium are also possible.Starting efficiency can be determined according to standard ISO 19438 (2013).As herein Described, starting efficiency can (for example, being directed to x microns or bigger of particle, wherein x be described herein under different partial sizes ) measure, and the starting efficiency of above range is applicable to a variety of partial sizes as described herein.In some embodiments In, x is 4 microns, so that the starting efficiency of above range is suitable for filtering out 4 microns or bigger of particle.

In some embodiments, the average efficiency of entire filter medium can greater than or equal to about 60%, be greater than or equal to About 70%, greater than or equal to about 80%, greater than or equal to about 90%, greater than or equal to about 95%, greater than or equal to about 96%, it is big In or equal to about 97%, greater than or equal to about 98%, greater than or equal to about 99%, greater than or equal to about 99.9%, be greater than or wait In about 99.99% or be about 100%.In some cases, the average efficiency of entire filter medium may be less than or equal to about 100%, less than or equal to about 99.99%, less than or equal to about 98%, less than or equal to about 97%, less than or equal to about 96%, Less than or equal to about 90%, less than or equal to about 80% or less than or equal to about 70%.The combination of above range is also possible (for example, greater than or equal to about 60% and less than or equal to about 100%, greater than or equal to about 70% and less than or equal to about 100%).The other values of the average efficiency of filter medium are also possible.

Filter medium as described herein can be used for the filtering of a variety of partial sizes.Can measure for capturing partial size is x (micron) Or the efficiency of the filter medium of bigger particle.(for example, root in the typical test for measurement layer or the efficiency of entire medium According to standard ISO 19438 (2013)), it can will taken on the ten of testing time equal part point in the upstream of this layer or medium under Swim selected partial size x (for example, wherein x be 1 micron, 3 microns, 4 microns, 5 microns, 7 microns, 10 microns, 15 microns, it is 20 micro- Rice, 25 microns or 30 microns) granule number.In general, partial size x means that x microns or bigger of particle will be by the layer or capture medium. The average value of upstream particle number and downstream particulate number can be obtained under selected partial size.By the average grain number (note of upstream Enter-C₀) and downstream average grain number (by-C), relationship [(1- [C/C can be passed through₀]) * 100%] determine to selected The filter efficiency test value of partial size.

As described herein, efficiency can be determined according to standard ISO 19438 (2013).The base that the test rises in 50mg/ The medium-sized test dust of ISO12103-3 is used under plinth upstream weight dust content (BUGL).Testing fluid is to be manufactured by Mobil Hydraulic air fluid AERO HFA MIL H-5606A.The test carries out under 0.06cm/ seconds face velocities until terminal pressure For 100kPa.Unless otherwise stated, the otherwise terminal pressure of dust containing capacity value as described herein and/or average efficiency value in 100kPa Lower determination.Average efficiency is at one minute intervals until reaching the average value of the efficiency value of terminal pressure measurement.Class can be used As scheme measure starting efficiency, starting efficiency refers to that medium is flat at 4 minutes, 5 minutes and 6 minutes after a test Equal efficiency measure.Unless otherwise specified, average efficiency as described herein and starting efficiency measured value refer to wherein x=4 The value of micron.

In some embodiments, the dust containing capacity of the entire filter medium including the layer comprising thin polymer short fiber can be big In or equal to about 10g/m², greater than or equal to about 20g/m², greater than or equal to about 50g/m², greater than or equal to about 100g/m², it is big In or equal to about 150g/m², greater than or equal to about 200g/m², greater than or equal to about 250g/m², greater than or equal to about 300g/m²、 Greater than or equal to about 350g/m², greater than or equal to about 300g/m², greater than or equal to about 350g/m², greater than or equal to about 400g/ m²Or greater than or equal to about 450g/m².In some cases, dust containing capacity may be less than or equal to about 600g/m², be less than or equal to About 550g/m², less than or equal to about 500g/m², less than or equal to about 450g/m², less than or equal to about 400g/m², be less than or wait In about 350g/m², less than or equal to about 300g/m², less than or equal to about 250g/m², less than or equal to about 200g/m², be less than or Equal to about 150g/m², less than or equal to about 100g/m², less than or equal to about 50g/m², less than or equal to about 25g/m²Or it is small In or equal to about 10g/m².The combination of above range is possible (for example, greater than or equal to about 10g/m²And less than or equal to about 500g/m², greater than or equal to about 50g/m²And less than or equal to about 300g/m²).The other values of DHC are possible.Dust containing capacity can It is determined using ISO 19438.

In some embodiments, the layer comprising thin polymer short fiber can be used for assigning entire filter medium relatively high Particulate efficiency and relatively high fluid separative efficiency.In some such embodiments, filter medium include comprising relative to Fluid to be separated has the layer and the second layer of the thin polymer short fiber of specific wetability.For example, including the short fibre of thin polymer The layer of dimension may include the blend that can be used for assigning two or more different thin polymer short fibers of this layer expectation wetability. For example, the layer comprising thin polymer short fiber may include hydrophobic thin polymer short fiber and hydrophilic polymer staple fiber.Hydrophobic fibre The combination of peacekeeping hydrophilic fibers can produce the packet compared with the fibrous layer individually formed by respective fiber with medium wetting characteristics Layer containing thin polymer short fiber.

It is wherein including the layer of thin polymer short fiber comprising may be selected in the embodiment of hydrophobic fiber and hydrophilic fibers The weight percent of hydrophobic fiber and hydrophilic fibers realizes desired wetability.For example, in some embodiments, such as base The weight percent of the total weight of fiber in layer, the hydrophobic thin polymer short fiber in layer can be greater than or equal to about 10 weights Amount %, greater than or equal to about 25 weight %, greater than or equal to about 30 weight %, greater than or equal to about 35 weight %, be greater than or wait In about 40 weight %, greater than or equal to about 45 weight %, greater than or equal to about 50 weight %, greater than or equal to about 55 weight %, Greater than or equal to about 60 weight %, greater than or equal to about 65 weight %, greater than or equal to about 70 weight %, greater than or equal to about 75 Weight %, greater than or equal to about 80 weight %, greater than or equal to about 85 weight % or greater than or equal to about 90 weight %.? Under some cases, based on the total weight of the fiber in layer, the weight percent of the hydrophobic thin polymer short fiber in layer is smaller than Or be equal to about 75 weight %, less than or equal to about 70 weight %, less than or equal to about 65 weight %, less than or equal to about 60 weights Amount %, less than or equal to about 55 weight %, less than or equal to about 50 weight %, less than or equal to about 45 weight %, be less than or wait In about 40 weight %, less than or equal to about 35 weight % or less than or equal to about 30 weight %.The combination of above range is can (for example, greater than or equal to about 25% and less than or equal to about 100%) of energy.In some embodiments, hydrophobic thin in layer The weight percent of polymer short fiber is 100%.In some embodiments, above-mentioned weight percent is based on layer (comprising appointing What resin) total dry solid weight.

In some embodiments, such as the total weight based on the fiber in layer, the hydrophilic thin polymer short fiber in layer Weight percent can greater than or equal to about 0 weight %, greater than or equal to about 5 weight %, greater than or equal to about 10 weight %, big In or be equal to about 15 weight %, greater than or equal to about 20 weight %, greater than or equal to about 25 weight %, greater than or equal to about 30 weights Amount %, greater than or equal to about 35 weight %, greater than or equal to about 40 weight %, greater than or equal to about 45 weight %, be greater than or wait In about 50 weight %, greater than or equal to about 55 weight %, greater than or equal to about 60 weight %, greater than or equal to about 65 weight %, Greater than or equal to about 75 weight % or greater than or equal to about 90 weight %.In some cases, based on the total of the fiber in layer Weight, the weight percent of the hydrophilic thin polymer short fiber in layer may be less than or equal to about 90 weight %, less than or equal to about 75 weight %, less than or equal to about 70 weight %, less than or equal to about 65 weight %, less than or equal to about 60 weight %, be less than Or be equal to about 55 weight %, less than or equal to about 50 weight %, less than or equal to about 45 weight %, less than or equal to about 40 weights Amount %, less than or equal to about 35 weight %, less than or equal to about 30 weight %, less than or equal to about 25 weight %, be less than or wait In about 20 weight %, less than or equal to about 15 weight %, less than or equal to about 10 weight % or less than or equal to about 5 weights Measure %.The combination of above range is possible (for example, greater than or equal to about 0% and less than or equal to about 90%).In some realities It applies in scheme, above-mentioned weight percent is based on the weight of total dry solid of layer (including any resin).

In some embodiments, including being designed to assign high fluid separative efficiency and both high particulate efficiencies The ensemble average fluid separative efficiency of the filter medium of the filter medium of layer comprising thin polymer short fiber can be about 30% to About 99.99% or higher (for example, about 40% to about 99.99%, about 50% to about 99.99%, about 60% to about 99.99%). For example, in certain embodiments, the mean flow separative efficiency of filter medium can at least about 30%, at least about 40%, extremely Few about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, at least about 98%, extremely Few about 99% or at least about 99.5%.In some cases, the mean flow separative efficiency of filter medium may be less than or equal to about 99.99%, less than or equal to about 99.95%, less than or equal to about 99.9%, less than or equal to about 99%, less than or equal to about 98%, less than or equal to about 95%, less than or equal to about 90%, less than or equal to about 80%, less than or equal to about 70%, be less than Or it is equal to about 60%, less than or equal to about 50% or less than or equal to about 40%.The combination of above range is possible.Its His range is also possible.

In some embodiments, including being designed to assign high fluid separative efficiency and both high particulate efficiencies The primary particles efficiency (for example, wherein x=4 microns) of the filter medium of layer comprising thin polymer short fiber can be greater than or equal to About 80%, greater than or equal to about 85%, greater than or equal to about 90%, greater than or equal to about 95%, greater than or equal to about 96%, it is big In or be equal to about 97%, greater than or equal to about 98%, greater than or equal to about 99% or greater than or equal to about 99.9%.One In a little situations, the primary particles efficiency of filter medium may be less than or equal to about 100%, less than or equal to about 99.99%, be less than or Equal to about 99%, less than or equal to about 98%, less than or equal to about 97%, less than or equal to about 95%, less than or equal to about 90% or less than or equal to about 85%.The combination of above range is also possible (for example, greater than or equal to about 80% and small In or be equal to about 100%, greater than or equal to about 90% and less than or equal to about 100%).The starting efficiency of filter medium other Value is also possible.

In some embodiments, the average grain efficiency (for example, wherein x=4 microns) of filter medium can be greater than or wait In about 85%, greater than or equal to about 90%, greater than or equal to about 95%, greater than or equal to about 96%, greater than or equal to about 97%, Greater than or equal to about 98%, greater than or equal to about 99% or greater than or equal to about 99.9%.In some cases, filtering is situated between The average grain efficiency of matter may be less than or equal to about 100%, less than or equal to about 99.99%, less than or equal to about 99%, be less than Or be equal to about 98%, less than or equal to about 97%, less than or equal to about 95% or less than or equal to about 90%.Above range Combination be also it is possible (for example, greater than or equal to about 85% and less than or equal to about 100%, greater than or equal to about 90% and Less than or equal to about 100%).The other values of the average grain efficiency of filter medium are also possible.

In some embodiments, the thickness of entire filter medium can greater than or equal to about 0.03mm, greater than or equal to about 0.05mm, greater than or equal to about 0.1mm, greater than or equal to about 0.2mm, greater than or equal to about 0.5mm, greater than or equal to about 1mm, Greater than or equal to about 5mm, greater than or equal to about 10mm, greater than or equal to about 15mm, greater than or equal to about 20mm, or be greater than or Equal to about 25mm.In some cases, the thickness of filter medium may be less than or equal to about 30mm, small less than or equal to about 25mm In about 20mm, less than or equal to about 15mm, less than or equal to about 10mm, less than or equal to about 5mm, less than or equal to about 1mm, or Person is less than or equal to about 0.5mm.All combinations of above range are possible (for example, greater than or equal to about 0.03mm and being less than Or it is equal to about 30mm, greater than or equal to about 0.05mm and less than or equal to about 20mm).The other values of the thickness of filter medium are can Can.The thickness of entire filter medium can be in 2N/cm²It is lower to be determined according to standard ISO 534 (2011).

Filter medium can have the service life of raising relative to certain typical filter medias.As mentioned in this article, the service life according to Standard ISO 4020 (2001) is measured.Mineral oil 4-6cST can be used at 23 DEG C as test fluid to be tested. Testing fluid includes the mixture respectively as 2 aluminum oxide of carbon black and Mira of organic pollutant and inorganic pollution.Test The flow of fluid is 36.7Lpm/m², and terminal differential pressure increases as 70kPa on clean filter medium.The diameter of test fixture For 90mm.Inorganic pollution is 20 grams of 2 aluminum oxide/20 liter mineral oil 4-6cST of Mira, and organic pollutant is 1.25 grams of charcoals Black/20 liters of mineral oil 4-6cST.Service life is determined to be in the terminal differential pressure for reaching 70kPa on the clean filter medium of contamination-free Required time in minutes.

In some embodiments, the average life span of filter medium can greater than or equal to about 3 minutes, greater than or equal to about 6 Minute, greater than or equal to about 10 minutes, greater than or equal to about 20 minutes, greater than or equal to about 40 minutes, greater than or equal to about 55 Minute, greater than or equal to about 60 minutes, greater than or equal to about 70 minutes, greater than or equal to about 85 minutes, greater than or equal to about 100 Minute, greater than or equal to about 125 minutes, greater than or equal to about 150 minutes, greater than or equal to about 175 minutes, greater than or equal to about 200 minutes or greater than or equal to about 225 minutes.In some cases, the average life span of filter medium may be less than or equal to about 250 minutes, less than or equal to about 225 minutes, less than or equal to about 200 minutes, less than or equal to about 175 minutes, be less than or wait In about 160 minutes, less than or equal to about 130 minutes, less than or equal to about 110 minutes, less than or equal to about 85 minutes, be less than or Equal to about 65 minutes, less than or equal to about 50 minutes or less than or equal to about 25 minutes.The combination of above range is also possible (for example, greater than or equal to about 3 minutes and less than or equal to about 200 minutes, greater than or equal to about 6 minutes and being less than or equal to About 250 minutes).In some embodiments, the filter medium including first layer, the second layer and third layer can have relatively high Service life (for example, greater than or equal to about 6 minutes and less than or equal to about 250 minutes).The other values of average life span are also possible. Service life can determine according to standard ISO 4020.

In some embodiments, the weight of determining of entire filter medium can be greater than or equal to about 5g/m², greater than or equal to about 10g/m², greater than or equal to about 25g/m², greater than or equal to about 50g/m², greater than or equal to about 100g/m², greater than or equal to about 150g/m², greater than or equal to about 200g/m², greater than or equal to about 300g/m², greater than or equal to about 400g/m², be greater than or equal to About 500g/m², greater than or equal to about 600g/m², greater than or equal to about 700g/m², greater than or equal to about 800g/m²Or it is greater than Or it is equal to about 900g/m².In some cases, the fixed of filter medium may be less than or equal to about 1000g/m again², less than or equal to about 900g/m², less than or equal to about 800g/m², less than or equal to about 700g/m², less than or equal to about 600g/m², be less than or equal to About 500g/m², less than or equal to about 400g/m², less than or equal to about 300g/m², less than or equal to about 200g/m², be less than or wait In about 150g/m², less than or equal to about 100g/m², less than or equal to about 50g/m²Or less than or equal to about 25g/m².It is above-mentioned The combination of range is possible (for example, greater than or equal to about 5g/m²And less than or equal to about 1000g/m², greater than or equal to about 10g/m²And less than or equal to about 800g/m²).Surely heavy other values are possible.Determining weight can be according to standard ISO 536 (2012) It determines.

In some embodiments, filter medium as described herein can have relatively high intensity.For example, in some implementations In scheme, the dry Mullen burst strength of entire filter can greater than or equal to about 0.5psi, greater than or equal to about 1psi, be greater than or Equal to about 2psi, greater than or equal to about 5psi, greater than or equal to about 10psi, greater than or equal to about 25psi, greater than or equal to about 50psi, greater than or equal to about 75psi, greater than or equal to about 100psi, greater than or equal to about 125psi, greater than or equal to about 150psi or greater than or equal to about 175psi.In some cases, dry Mullen burst strength may be less than or equal to about 200psi, less than or equal to about 175psi, less than or equal to about 150psi, less than or equal to about 125psi, less than or equal to about 100psi, less than or equal to about 75psi, less than or equal to about 50psi, less than or equal to about 25psi or less than or equal to about 10psi.The combination of above range is also possible (for example, greater than or equal to about 1psi and less than or equal to about 200psi, being greater than Or equal to about 2psi and less than or equal to about 175psi).The other values of dry Mullen burst strength are also possible.Dry Mullen burst Intensity can be determined according to normalized thyroxine 03om-97 (1997).

In some embodiments, transverse direction (cross direction) dry tensile elongation of entire filter medium can be big In or be equal to about 1%, greater than or equal to about 2%, greater than or equal to about 3%, greater than or equal to about 5%, greater than or equal to about 7%, greater than or equal to about 9%, greater than or equal to about 11%, greater than or equal to about 13% or greater than or equal to about 15%.? Under some cases, lateral dry tensile elongation may be less than or equal to about 20%, less than or equal to about 18%, less than or equal to about 15%, less than or equal to about 13%, less than or equal to about 11%, less than or equal to about 9%, less than or equal to about 7%, be less than or Equal to about 5% or less than or equal to about 3%.The combination of above range be also it is possible (for example, greater than or equal to about 1% and Less than or equal to about 20%, greater than or equal to about 2% and less than or equal to about 13%).The other values of lateral dry tensile elongation It is also possible.Lateral dry tensile elongation can use 4 inches of test span and 12 English according to normalized thyroxine 94om-96 (1996) The jaw separation speed of very little/minute determines.

In some embodiments, machine direction (machine direction) the dry tensile elongation of entire filter medium Rate can greater than or equal to about 1%, greater than or equal to about 2%, greater than or equal to about 3%, greater than or equal to about 5%, be greater than or wait In about 7%, greater than or equal to about 9%, greater than or equal to about 11%, greater than or equal to about 13% or greater than or equal to about 15%.In some cases, machine direction dry tensile elongation may be less than or equal to about 20%, less than or equal to about 18%, it is small In or be equal to about 15%, less than or equal to about 13%, less than or equal to about 11%, less than or equal to about 9%, less than or equal to about 7%, less than or equal to about 5% or less than or equal to about 3%.The combination of above range be also it is possible (for example, be greater than or Equal to about 1% and less than or equal to about 20%, greater than or equal to about 2% and less than or equal to about 13%).Machine direction dry tensile The other values of elongation are also possible.Machine direction dry tensile elongation can use 4 English according to normalized thyroxine 94om-96 (1996) The jaw separation speed of very little test span and 12 inch/minutes determines.

In some embodiments, the lateral dry tensile strength of entire filter medium can greater than or equal to about 1 pounds per inch, Greater than or equal to about 2 pounds per inch, greater than or equal to about 5 pounds per inch, greater than or equal to about 10 pounds per inch, greater than or equal to about 25 pounds per inch, greater than or equal to about 50 pounds per inch, greater than or equal to about 75 pounds per inch, greater than or equal to about 100 pounds per inch, Or greater than or equal to about 125 pounds per inch.In some cases, lateral dry tensile strength may be less than or equal to about 150 pounds/English It is very little, less than or equal to about 125 pounds per inch, less than or equal to about 100 pounds per inch, less than or equal to about 75 pounds per inch, be less than or Equal to about 60 pounds per inch, less than or equal to about 45 pounds per inch, less than or equal to about 30 pounds per inch or less than or equal to about 15 pounds per inch.The combination of above range is also possible (for example, greater than or equal to about 1 pounds per inch and less than or equal to about 150 Pounds per inch, greater than or equal to about 2 pounds per inch and less than or equal to about 125 pounds per inch).Machine direction dry tensile strength its It is also possible that he, which is worth,.Machine direction dry tensile strength can use the folder of 1 inch/minute according to normalized thyroxine 94om-96 (1996) Pawl separating rate determines.

In some embodiments, the machine direction dry tensile strength of entire filter medium can be greater than or equal to about 1 pound/English It is very little, greater than or equal to about 2 pounds per inch, greater than or equal to about 5 pounds per inch, greater than or equal to about 10 pounds per inch, be greater than or equal to About 25 pounds per inch, greater than or equal to about 50 pounds per inch, greater than or equal to about 75 pounds per inch, greater than or equal to about 100 pounds/English It is very little, greater than or equal to about 125 pounds per inch, greater than or equal to about 150 pounds per inch or greater than or equal to about 175 pounds per inch. In some cases, machine direction dry tensile strength may be less than or equal to about 200 pounds per inch, less than or equal to about 175 pounds/English It is very little, less than or equal to about 150 pounds per inch, less than or equal to about 125 pounds per inch, less than or equal to about 100 pounds per inch, be less than Or be equal to about 75 pounds per inch, less than or equal to about 60 pounds per inch, less than or equal to about 45 pounds per inch, less than or equal to about 30 Pounds per inch or less than or equal to about 15 pounds per inch.The combination of above range is also possible (for example, greater than or equal to about 1 Pounds per inch and less than or equal to about 200 pounds per inch, greater than or equal to about 2 pounds per inch and less than or equal to about 150 pounds/English It is very little).The other values of machine direction dry tensile strength are also possible.Machine direction dry tensile strength can be according to normalized thyroxine 94om- 96 (1996) are determined using the jaw separation speed of 1 inch/minute.

In some embodiments, entire filter can express advantageous air penetrability.In some embodiments, entirely The air penetrability of filter medium can greater than or equal to about 0.3CFM, greater than or equal to about 0.4CFM, greater than or equal to about 1CFM, be greater than Or equal to about 5CFM, greater than or equal to about 10CFM, greater than or equal to about 25CFM, greater than or equal to about 50CFM, be greater than or equal to About 75CFM, greater than or equal to about 100CFM, greater than or equal to about 125CFM, greater than or equal to about 150CFM, greater than or equal to about 175CFM, greater than or equal to about 200CFM, greater than or equal to about 225CFM, greater than or equal to about 250CFM or be greater than or wait In about 275CFM.In some cases, the air penetrability of entire filter medium may be less than or equal to about 300CFM, less than or equal to about 275CFM, less than or equal to about 250CFM, less than or equal to about 225CFM, less than or equal to about 200CFM, less than or equal to about 175CFM, less than or equal to about 150CFM, less than or equal to about 125CFM, less than or equal to about 100CFM, less than or equal to about 75CFM, less than or equal to about 50CFM or less than or equal to about 25CFM.The combination of above range be also it is possible (for example, Greater than or equal to about 1CFM and less than or equal to about 300CFM, greater than or equal to about 1CFM and less than or equal to about 250CFM, big In or be equal to about 0.3CFM and less than or equal to about 300CFM, greater than or equal to about 0.3CFM and less than or equal to about 250CFM). The other values of air penetrability are also possible.TAPPIT-251 can be used to determine for air penetrability.

It in some embodiments, can be relatively low across the pressure drop of entire filter medium.For example, in some embodiments In, the pressure drop across entire filter medium may be less than or equal to about 80kPa, less than or equal to about 70kPa, less than or equal to about 60kPa, less than or equal to about 50kPa, less than or equal to about 40kPa, less than or equal to about 30kPa, less than or equal to about 20kPa, less than or equal to about 10kPa, less than or equal to about 5kPa, less than or equal to about 1kPa, or less than or equal to about 0.5kPa.In some cases, the pressure drop of entire filter medium can greater than or equal to about 0.01kPa, greater than or equal to about 0.02kPa is greater than or equal to greater than or equal to about 0.1kPa greater than or equal to about 0.5kPa greater than or equal to about 0.05kPa About 1kPa, greater than or equal to about 5kPa, greater than or equal to about 10kPa, greater than or equal to about 20kPa, greater than or equal to about 30kPa, greater than or equal to about 40kPa, greater than or equal to about 50kPa, greater than or equal to about 60kPa, or greater than or equal to about 70kPa.The combination of above range is also possible (for example, greater than or equal to about 0.05kPa and less than or equal to about 80kPa, greatly In or equal to about 0.1kPa and less than or equal to about 50kPa, greater than or equal to about 0.05kPa and less than or equal to about 50kPa, greatly In or equal to about 0.01kPa and less than or equal to about 80kPa).The other values of pressure drop are also possible.Plain film pressure drop uses ISO 3968 standards (evaluation criteria of -- filter -- pressure difference relative discharge feature that is, Hydraulic fluid power) measurement.When with 0.67cm/ When the face velocity of second makes the clean hydraulic fluid of 15cSt pass through filter medium, voltage drop value is measured.

In one group of specific embodiment, filter media design is separated into effect at the high particulate efficiency of imparting and high fluid Both rates.In some embodiments, medium includes more than first polymer comprising average diameter less than or equal to about 1 micron The first layer of more than second polymer short fiber of staple fiber and average diameter less than or equal to 1 micron.In certain embodiments In, more than first polymer short fiber and more than second polymer short fiber are different.In some cases, the water of first layer Contact angle is about 30 degree to 165 degree.Medium may include the second layer comprising fiber of the average diameter greater than or equal to about 4 microns. In some embodiments, the air penetrability of filter medium is 0.3CFM to 300CFM, and determining weight is 5g/m²To 1000g/m².In addition Ground or alternatively, in some embodiments, the dust containing capacity of filter medium can be greater than or equal to about 10g/m², greater than or equal to about 20g/m², greater than or equal to about 50g/m², greater than or equal to about 100g/m², greater than or equal to about 150g/m², greater than or equal to about 200g/m², greater than or equal to about 250g/m², greater than or equal to about 300g/m², greater than or equal to about 350g/m², be greater than or equal to About 300g/m², greater than or equal to about 350g/m², greater than or equal to about 400g/m²Or greater than or equal to about 450g/m².One In a little situations, dust containing capacity may be less than or equal to about 600g/m², less than or equal to about 550g/m², less than or equal to about 500g/m²、 Less than or equal to about 450g/m², less than or equal to about 400g/m², less than or equal to about 350g/m², less than or equal to about 300g/ m², less than or equal to about 250g/m², less than or equal to about 200g/m², less than or equal to about 150g/m², less than or equal to about 100g/m², less than or equal to about 50g/m², less than or equal to about 25g/m²Or less than or equal to about 10g/m².Above range Combination be possible (for example, greater than or equal to about 10g/m²And less than or equal to about 600g/m², greater than or equal to about 50g/m² And less than or equal to about 300g/m²).The other values of DHC are possible.ISO 19438 can be used to determine for dust containing capacity.

In general, one or more layers (for example, first layer, the second layer, third layer) may include any suitable fiber.Example Such as, in some embodiments, the layer in filter medium (for example, second layer, third layer) may include synthetic fibers.Synthetic fibers It may include the synthetic fibers of any suitable type.The example of suitable synthetic fibers includes staple fiber, polyester (for example, poly- to benzene Naphthalate, polybutylene terephthalate (PBT)), it is polycarbonate, polyamide (for example, various nylon polymers), poly- Fragrant amide, polyimides, polyethylene, polypropylene, polyether-ketone, polyolefin, polyacrylic, polyvinyl alcohol, regenerated cellulose (example Such as, synthetic cellulose such as lyocell, artificial silk, acrylic compounds), polyacrylonitrile, polysulfones, polyvinylidene fluoride (PVDF), poly- second The copolymer of alkene and PVDF, the copolymer of polypropylene and PVDF, Poly-s 179, polyether sulfone, and combinations thereof.In some embodiments In, synthetic fibers are organic polymer fiber.Synthetic fibers may also include multicomponent fibre (that is, the fiber with a variety of compositions Such as bicomponent fibre) and binder fibre.In some embodiments, synthetic fibers are the form of continuous fiber.In other realities It applies in scheme, synthetic fibers are the short of the avarage fiber diameter that avarage fiber diameter is greater than thin polymer short fiber as described herein The form of fiber.Layer also may include the combination of the synthetic fibers of more than one type.It should be understood that other kinds of conjunction also can be used At fiber type.In certain embodiments, above-mentioned fiber type can be applied to the synthetic fibers of entire medium (for example, entire Medium may include one of above-mentioned synthetic fibers or more).

In some embodiments, the synthetic fibers of one or more layers (for example, first layer, the second layer, third layer) Average diameter can be greater than or be equal to about 0.1 micron, greater than or equal to about 0.3 micron, greater than or equal to about 0.5 micron, Greater than or equal to about 1 micron, greater than or equal to about 2 microns, greater than or equal to about 3 microns, greater than or equal to about 4 microns, be greater than Or equal to about 5 microns, greater than or equal to about 8 microns, greater than or equal to about 10 microns, greater than or equal to about 12 microns, be greater than or Equal to about 15 microns or greater than or equal to about 20 microns.In some cases, the average diameter of synthetic fibers is smaller than or waits In about 30 microns, less than or equal to about 20 microns, less than or equal to about 15 microns, less than or equal to about 10 microns, be less than or wait In about 7 microns, less than or equal to about 5 microns, less than or equal to about 4 microns, less than or equal to about 1.5 microns, be less than or equal to About 1 micron, less than or equal to about 0.8 micron or less than or equal to about 0.5 micron.The combination of above range is also possible (for example, greater than or equal to about 1 micron and less than or equal to about 5 microns).The other values of avarage fiber diameter are also possible.? In certain embodiments, the range of above-mentioned avarage fiber diameter can be applied to the synthetic fibers of entire medium (for example, entire medium It may include one or more interior synthetic fibers of the avarage fiber diameter in above range).

In some cases, synthetic fibers can be continuous (for example, meltblown fibers, melt spun fibre, spun-bonded fibre, quiet Electricity spinning fibre, centrifugal spinning fiber etc.).For example, the average length of synthetic fibers can greater than or equal to about 1 inch, be greater than or Equal to about 50 inches, greater than or equal to about 100 inches, greater than or equal to about 300 inches, greater than or equal to about 500 inches, be greater than Or equal to about 700 inches or greater than or equal to about 900 inches.In some cases, the average length of synthetic fibers is smaller than Or be equal to about 1000 inches, less than or equal to about 800 inches, less than or equal to about 600 inches, less than or equal to about 400 inches, Or less than or equal to about 100 inches.The combination of above range is also possible (for example, greater than or equal to about 50 inches and small In or equal to about 1000 inches).The other values of average fiber length are also possible.

In other embodiments, synthetic fibers are discrete (for example, staple fibers).For example, in some embodiment party In case, the average lengths of the synthetic fibers in one or more layers in filter medium can be greater than or equal to about 0.025mm, big In or equal to about 0.05mm, greater than or equal to about 0.5mm, greater than or equal to about 1mm, greater than or equal to about 2mm, be greater than or equal to About 4mm, greater than or equal to about 6mm, greater than or equal to about 8mm, greater than or equal to about 10mm, greater than or equal to about 12mm or Greater than or equal to about 15mm.In some cases, the average length of synthetic fibers may be less than or equal to about 25mm, be less than or equal to About 20mm, less than or equal to about 15mm, less than or equal to about 12mm, less than or equal to about 10mm, less than or equal to about 8mm, small In or equal to about 6mm, less than or equal to about 4mm, less than or equal to about 2mm, less than or equal to about 1mm or be less than or equal to About 0.5mm.The combination of above range is also possible (for example, greater than or equal to about 1mm and less than or equal to about 4mm).It is average The other values of fibre length are also possible.In certain embodiments, the range of above-mentioned average fiber length can be applied to whole The synthetic fibers of a medium.

In some embodiments, the synthesis in one or more layers (for example, first layer, the second layer, third layer) is fine The weight percent of dimension can be relatively high.For example, in some embodiments, the weight of the synthetic fibers in one or more layers Percentage can greater than or equal to about 0.5 weight %, greater than or equal to about 1 weight %, greater than or equal to about 2 weight %, be greater than or Equal to about 20 weight %, greater than or equal to about 40 weight %, greater than or equal to about 60 weight %, greater than or equal to about 80 weights Measure %, greater than or equal to about 90 weight % or greater than or equal to about 95 weight %.In some cases, one or more The weight percent of layer and/or the synthetic fibers in entire filter medium may be less than or equal to about 100 weight %, be less than or equal to About 98 weight %, less than or equal to about 85 weight %, less than or equal to about 75 weight %, less than or equal to about 50 weight %, small In or equal to about 25 weight %, less than or equal to about 10 weight % or less than or equal to about 5 weight %.The group of above range Close is also possible (for example, greater than or equal to about 2 weight % and less than or equal to about 100 weight %).One or more layers And/or the other values of the weight percent of the synthetic fibers in entire filter medium are also possible.In some embodiments, Layer includes the synthetic fibers of 100 weight %.In some embodiments, the layer of filter medium is respectively relative to layer or filter medium In fiber total amount include above range fiber.In certain embodiments, above range can be applied to the conjunction of entire medium At fiber.

In some embodiments, one or more layers (for example, layer, the second layer comprising thin polymer short fiber) And/or entire filter medium may include binder fibre.Binder fibre usually accounts for one or more layers and/or entire filter medium Small weight percent.For example, binder fibre can account for the small of the weight percent of the total fiber in layer or in entire filter medium In about 10% or be less than about 5% (for example, 2% to 5%).

In some embodiments, one or more layers in filter medium are (for example, include thin polymer short fiber Layer, the second layer) and/or entirely filter medium may include one or more of cellulose fibres, such as cork fibrous, hardwood fibre Dimension, the mixture of hardwood fiber and cork fibrous, regenerated celulose fibre are (for example, artificial silk, fibrillated synthetic cellulose fiber Such as Lyocell fibers), micron fibrillating fibre element and mechanical pulp fibre be (for example, ground wood pulp, chemically treated mechanical paper Slurry and thermomechanical pulp).Exemplary cork fibrous includes from mercerising Southern Pine (for example, mercerising Southern Pine fiber or " HPZ fibre Dimension "), northern bleached softwood kraft paper is (for example, (" robur flash of light is fine for the fiber obtained from robur flash of light (Robur Flash) Dimension ")), southern bleached softwood brown paper is (for example, (" pine is fine for Brunswick for the fiber obtained from Brunswick (Brunswick) pine Dimension ")) or chemically treated mechanical pulp (" CTMP fiber ") obtain fiber.For example, HPZ fiber can be from Tennessee State Meng The Buckeye Technologies company of Fiss obtains；Robur flashing fiber can be from Stockholm, SWE Rottneros AB is obtained；And Brunswick's pine fiber can be obtained from the Georgia-Pacific of Atlanta, Georgia ?.Exemplary hardwood fiber includes the fiber (" eucalyptus fibers ") obtained from eucalyptus.Eucalyptus fibers are purchased from such as Soviet Union of (1) Brazil Prick the Suzano Group (" Su Zhanuo fiber ") of promise；(2) the Group Portucel Soporcel of Portugal Cacia (" Cacia fiber ")；(3) the Tembec company (" Tarascon fiber ") of Quebec, CAN Temiscaming；(4) German The Kartonimex Intercell (" Acacia fiber ") of Dusseldorf；(5) Mead- in Stamford, Connecticut city Westvaco (" Westvaco fiber ")；And the Georgia-Pacific (" Leaf in (6) Atlanta, Georgia city River fiber ").

In one or more layers (for example, layer, the second layer comprising thin polymer short fiber) and/or entire filter medium Cellulose fibre average diameter can be greater than or be equal to about 1 micron, greater than or equal to about 2 microns, greater than or equal to about 3 Micron, greater than or equal to about 4 microns, greater than or equal to about 5 microns, greater than or equal to about 8 microns, it is micro- greater than or equal to about 10 Rice, greater than or equal to about 15 microns, greater than or equal to about 20 microns, greater than or equal to about 30 microns or greater than or equal to about 40 microns.In some cases, the average diameter of cellulose fibre may be less than or equal to about 50 microns, it is micro- less than or equal to about 40 Rice, less than or equal to about 30 microns, less than or equal to about 20 microns, less than or equal to about 15 microns, it is micro- less than or equal to about 10 Rice, less than or equal to about 7 microns, less than or equal to about 5 microns, it is less than or equal to about 4 microns or micro- less than or equal to about 2 Rice.The combination of above range is also possible (for example, greater than or equal to about 1 micron and less than or equal to about 5 microns).Average fibre It is also possible for tieing up the other values of diameter.

In some embodiments, cellulose fibre can have average length.For example, in some embodiments, fiber The average length of cellulose fiber can greater than or equal to about 0.5mm, greater than or equal to about 1mm, greater than or equal to about 2mm, be greater than or wait In about 3mm, greater than or equal to about 4mm, greater than or equal to about 5mm, greater than or equal to about 6mm or greater than or equal to about 8mm. In some cases, the average length of cellulose fibre may be less than or equal to about 10mm, less than or equal to about 8mm, be less than or wait In about 6mm, less than or equal to about 4mm, less than or equal to about 2mm or less than or equal to about 1mm.The combination of above range It is possible (for example, greater than or equal to about 1mm and less than or equal to about 3mm).The other values of average fiber length are also possible 's.

Type regardless of cellulose fibre, in some embodiments, for example, based on the fiber in layer or medium In total weight, one or more layers (for example, layer, the second layer comprising thin polymer short fiber) and/or entire filter medium Cellulose fibre weight percent can greater than or equal to about 0 weight %, greater than or equal to about 5 weight %, be greater than or equal to About 10 weight %, greater than or equal to about 15 weight %, greater than or equal to about 45 weight %, greater than or equal to about 65 weight % or Person is greater than or equal to about 90 weight %.In some cases, for example, the total weight based on the fiber in layer or medium, one or The weight percent of more layers and/or the cellulose fibre in entire filter medium may be less than or equal to about 100 weight %, small In or be equal to about 85 weight %, less than or equal to about 55 weight %, less than or equal to about 20 weight %, less than or equal to about 10 weights Measure % or less than or equal to about 2 weight %.The combination of above range is also possible (for example, greater than or equal to about 0 weight Measure % and less than or equal to about 100 weight %).The other values of the weight percent of cellulose fibre in one or more layers It is also possible.In some embodiments, one or more layers (for example, second layer) and/or entire filter medium include The cellulose fibre of 100 weight %.In other embodiments, one or more layers are (for example, include the short fibre of thin polymer The layer of dimension) and/or entire cellulose fibre of the filter medium comprising 0 weight %.In some embodiments, layer or medium difference Total weight relative to the fiber in this layer or medium includes the cellulose fibre of above range.In some embodiments, on State the weight that weight percent is based on total dry solid of layer (comprising any resin).

Comprising fibrillating fibre (for example, fibrillated lyocell (for example, artificial silk, lyocell), micro- in wherein layer Rice fibrillating fibre element, nanofibrillated cellulose, fibrillation synthetic fibers include nanometer fibrillation synthetic fibers (for example, by Such as polyester, Nomex, contraposition Nomex, meta position Nomex, polyimides, polyethylene, polypropylene, gathers polyamide The fibrillation of the synthetic polymer formation of ether ether ketone, polyethylene terephthalate, polyolefin, nylon and/or acrylic compounds Fiber), fibrillation natural fiber (for example, hardwood, cork)) embodiment in, the type regardless of fibrillating fibre, example Such as, the total weight based on the fiber in layer or medium, one or more layers are (for example, the layer comprising thin polymer short fiber, Two layers) and/or the fibrillating fibre in entire filter medium weight percent can greater than or equal to about 0 weight %, be greater than or Equal to about 1 weight %, greater than or equal to about 5 weight %, greater than or equal to about 10 weight %, greater than or equal to about 20 weight %, Greater than or equal to about 30 weight %, greater than or equal to about 40 weight %, greater than or equal to about 50 weight %, greater than or equal to about 60 Weight %, greater than or equal to about 70 weight % or greater than or equal to about 80 weight %.In some cases, for example, being based on layer Or the total weight of the fiber in medium, the weight hundred of one or more layers and/or the fibrillating fibre in entire filter medium Point than may be less than or equal to about 98 weight %, less than or equal to about 95 weight %, less than or equal to about 90 weight %, be less than or wait In about 80 weight %, less than or equal to about 70 weight %, less than or equal to about 60 weight %, less than or equal to about 50 weight %, Less than or equal to about 40 weight %, less than or equal to about 30 weight %, less than or equal to about 20 weight % or be less than or equal to About 10%.The combination of above range is also possible (for example, greater than or equal to about 0 weight % and less than or equal to about 98 weights Measure %, greater than or equal to about 0 weight % and less than or equal to about 80 weight %).One or more layers and/or entire filtering are situated between The other values of the weight percent of fibrillating fibre in matter are also possible.In some embodiments, layer or filter medium It may include the fibrillating fibre of 0 weight %.In some embodiments, layer or filter medium are respectively relative to the layer or filtering is situated between The total weight of fiber in matter includes the fibrillating fibre of above range.In some embodiments, above-mentioned weight percent base In the weight of total dry solid of layer (including any resin).

As known to persons of ordinary skill in the art, fibrillating fibre includes the parent for being branched off into the fibrinogen of smaller diameter Fiber, the fibrinogen of smaller diameter can further be branched off into the fibrinogen of even smaller diameter in some cases, further Branch is also possible.Branch's property of fibrinogen generates high surface area, and can increase in web fibrillating fibre with The quantity of contact point between fiber.The point contacted between the fibrillating fibre of net and other fibers and/or component it is such Increase the mechanical property (for example, flexible, intensity) and/or strainability characteristic that can help to improve web.

In some embodiments, precursor fiber can have the average diameter in micron range.For example, precursor fiber is flat Equal diameter can greater than or equal to about 1 micron, greater than or equal to about 5 microns, greater than or equal to about 10 microns, greater than or equal to about 20 Micron, greater than or equal to about 30 microns, greater than or equal to about 40 microns, greater than or equal to about 50 microns, greater than or equal to about 60 Micron or greater than or equal to about 70 microns.In some embodiments, the average diameter of precursor fiber may be less than or equal to about 75 microns, less than or equal to about 55 microns, less than or equal to about 35 microns, less than or equal to about 25 microns, less than or equal to about 15 microns, less than or equal to about 10 microns or less than or equal to about 5 microns.The combination of above range is also possible (example Such as, the average diameter of precursor fiber is greater than or equal to about 1 micron and less than or equal to about 25 microns).Other ranges are also possible 's.

In other embodiments, precursor fiber can have the average diameter in nanometer range.For example, in some implementations In scheme, the average diameter of precursor fiber be smaller than about 1 micron, less than or equal to about 0.8 micron, it is micro- less than or equal to about 0.5 Rice, less than or equal to about 0.1 micron, less than or equal to about 0.05 micron, less than or equal to about 0.02 micron, less than or equal to about 0.01 micron or less than or equal to about 0.005 micron.In some embodiments, the average diameter of precursor fiber can be greater than Or be equal to about 0.003 micron, greater than or equal to about 0.004 micron, greater than or equal to about 0.01 micron, greater than or equal to about 0.05 Micron, greater than or equal to about 0.1 micron or greater than or equal to about 0.5 micron.The combination of above range is also possible (example Such as, the average diameter of precursor fiber is greater than or equal to about 0.004 micron and less than or equal to about 0.02 micron).Other ranges It is possible.

The average diameter of fibrinogen is usually less than the average diameter of precursor fiber.According to the average diameter of precursor fiber, In some embodiments, the average diameter of fibrinogen may be less than or equal to about 25 microns, less than or equal to about 20 microns, be less than or Equal to about 10 microns, less than or equal to about 5 microns, less than or equal to about 1 micron, less than or equal to about 0.5 micron, be less than or wait In about 0.1 micron, less than or equal to about 0.05 micron or less than or equal to about 0.01 micron.In some embodiments, former The average diameter of fiber can greater than or equal to about 0.003 micron, greater than or equal to about 0.01 micron, it is micro- greater than or equal to about 0.05 Rice, greater than or equal to about 0.1 micron, greater than or equal to about 0.5 micron, greater than or equal to about 1 micron, it is micro- greater than or equal to about 5 Rice, greater than or equal to about 10 microns or greater than or equal to about 20 microns.The combination of above range is also possible (for example, former The average diameter of fiber is greater than or equal to about 0.01 micron and less than or equal to about 20 microns).Other ranges are also possible.

Fibrillation level can be measured according to any number of appropriate method.For example, can be according to by TAPPI test method Canadian Standard Freeness (CSF) as defined in the freedom of T 227om 09 (2009) paper pulp is tested to measure fibrillating fibre Fibrillation is horizontal.The test can provide average CSF value.

In some embodiments, the average CSF value of fibrillating fibre used in one or more layers can be about 5mL to about 750mL.In certain embodiments, the average CSF value of fibrillating fibre used in one or more layers can More than or equal to 1mL, greater than or equal to about 10mL, greater than or equal to about 20mL, greater than or equal to about 35mL, greater than or equal to about 45mL, greater than or equal to about 50mL, greater than or equal to about 65mL, greater than or equal to about 70mL, greater than or equal to about 75mL, be greater than Or equal to about 80mL, greater than or equal to about 100mL, greater than or equal to about 150mL, greater than or equal to about 175mL, be greater than or equal to About 200mL, greater than or equal to about 250mL, greater than or equal to about 300mL, greater than or equal to about 350mL, greater than or equal to about 500mL, greater than or equal to about 600mL, greater than or equal to about 650mL, greater than or equal to about 700mL or greater than or equal to about 750mL。

In some embodiments, the average CSF value of fibrillating fibre used in one or more layers is smaller than Or equal to about 800mL, less than or equal to about 750mL, less than or equal to about 700mL, less than or equal to about 650mL, be less than or wait In about 600mL, less than or equal to about 550mL, less than or equal to about 500mL, less than or equal to about 450mL, less than or equal to about 400mL, less than or equal to about 350mL, less than or equal to about 300mL, less than or equal to about 250mL, less than or equal to about 225mL, less than or equal to about 200mL, less than or equal to about 150mL, less than or equal to about 100mL, less than or equal to about 90mL, Less than or equal to about 85mL, less than or equal to about 70mL, less than or equal to about 50mL, less than or equal to about 40mL, be less than or wait In about 25mL, less than or equal to about 10mL or less than or equal to about 5mL.The combination of above range be also it is possible (for example, Greater than or equal to about 10mL and less than or equal to about 300mL).Other ranges are also possible.Made in one or more layers The average CSF value of fibrillating fibre can the fibril chemical fibre based on a type of fibrillating fibre or more than one type Dimension.

In some embodiments, one or more layers (for example, layer, the second layer comprising thin polymer short fiber) And/or entire filter medium substantially free of glass fibre (for example, glass fibre, less than 1 weight %, glass fibre is about 0 weight Measure % to about 1 weight %).For example, layer, the second layer and/or entire filter medium comprising thin polymer short fiber may include 0 weight Measure the glass fibre of %.Filter medium and filter device substantially free of glass fibre can be conducive to certain applications (for example, combustion Fuel-water separation, particle separation in material system) because glass fibre may fall off and leach sodium ion (for example, Na⁺), this It will lead to physical abrasion and soap formed.For example, glass fibre, which falls off, may cause fuel injector blocking (such as in high-pressure common rail In).In other embodiments, the second layer is optionally including glass fibre (for example, micro- glass fibre and/or short Cut glass fibre).

However, in other embodiments, one or more layers and/or entire filter medium in filter medium can Comprising glass fibre (for example, micro- glass fibre, short glass fiber, or combinations thereof).The average diameter of glass fibre can be such as Less than or equal to about 30 microns, less than or equal to about 25 microns, less than or equal to about 15 microns, less than or equal to about 12 microns, Less than or equal to about 10 microns, less than or equal to about 9 microns, less than or equal to about 7 microns, less than or equal to about 5 microns, be less than Or equal to about 3 microns or less than or equal to about 1 micron.In some cases, the avarage fiber diameter of glass fibre can be greater than Or be equal to about 0.1 micron, greater than or equal to about 0.3 micron, greater than or equal to about 1 micron, greater than or equal to about 3 microns or More than or equal to about 7 microns, greater than or equal to about 9 microns, greater than or equal to about 11 microns or greater than or equal to about 20 microns. The combination of above range is also possible (for example, greater than or equal to about 0.1 micron and less than or equal to about 9 microns).Average fibre It is also possible for tieing up the other values of diameter.

In some embodiments, the weight percent of glass fibre can greater than or equal to about 0 weight %, be greater than or equal to About 2 weight %, greater than or equal to about 5 weight %, greater than or equal to about 10 weight % or greater than or equal to about 15 weight %. In some cases, the weight percent of the glass fibre in layer may be less than or equal to about 26 weight %, less than or equal to about 20 Weight %, less than or equal to about 15 weight %, less than or equal to about 10 weight %, less than or equal to about 5 weight %, be less than or wait In about 2 weight % or less than or equal to about 1 weight %.The combination of above range is also possible (for example, being greater than or equal to About 0 weight % and less than or equal to about 10 weight %).The other values of the weight percent of glass fibre in layer are also possible 's.In some embodiments, the total weight for the fiber that layer or filter medium are respectively relative in this layer or filter medium includes The glass fibre of above range.In some embodiments, above-mentioned weight percent is based on the total dry of layer (including any resin) The weight of solid.

In some embodiments, other than plurality of fibers, one or more layers and/or entire filter medium may be used also Include other components such as resin, surface treatment and/or additive.In general, can be used any suitable resin desired to realize Characteristic.For example, resin can be polymer, based on water, solvent-based, dry strength and/or wet strength.In certain realities It applies in scheme, resin also may include additive, such as fire retardant, hydrophobic additive, hydrophilic additive, viscose glue, nano particle, boiling Stone, natural polymer (starch, natural gum), cellulose derivative (for example, carboxymethyl cellulose, methylcellulose, hemicellulose), Synthetic polymer (for example, phenols, latex, polyamide, polyacrylamide, urea-formaldehyde, melamine-formaldehyde, polyamide), carbon Fiber, particle, active carbon, vermiculite (vermiculate), perlite, organosilicon, surfactant, coupling agent, crosslinking agent (crosslinking agent), conductive additive, viscosity modifier, waterproofing agent, crosslinking agent (cross-linker) and/or pH Regulator, and/or diatomite.It should be understood that resin may include or can not include other components.In general, any annexing ingredient With finite quantity such as resin less than 40 weight %, resin less than 20 weight %, resin less than 10 weight %, resin it is small Exist in 5 weight %.

In some embodiments, one or more layers (for example, layer, the second layer comprising thin polymer short fiber) At least part usable resins of fiber coat and do not block substantially the hole of web.In some cases, essentially all Fiber can be coated and substantially not plugging hole.

In some embodiments, resin can be adhesive resin.Adhesive resin be not fibers form and with it is above-mentioned Binder fibre (for example, multicomponent fibre) is different.In general, adhesive resin can have any suitable composition.For example, adhesive Resin may include thermoplastic resin (for example, acrylic compounds, polyvinyl acetate, polyester, polyamide), thermosetting resin (for example, Epoxy resin, phenolic resin), or combinations thereof.In some cases, adhesive resin includes vinyl acetate resin, asphalt mixtures modified by epoxy resin Rouge, polyester resin, conjugated polyester resin, polyvinyl alcohol resin, acrylic resin (such as styrene acrylic) and phenol One of urea formaldehyde or more.Other resins are also possible.

It as described further below, can in any suitable manner include that resin is for example added to by fiber with hygrometric state. In some embodiments, resin coats fiber and for being adhering to each other fiber to promote the adherency between fiber.It can make Fiber is coated with any suitable method or equipment, for example, coated using curtain coating, rotogravure application, molten painting, dip-coating, knife roller type, Or spin coating etc..In some embodiments, adhesive precipitating when being added into fiber blends.It in the appropriate case, can be with Such as any suitable precipitating reagent (for example, epichlorohydrin, fluorocarbon) is provided to fiber by being injected in blend. In some embodiments, when being added to fiber, resin is so that one or more layers or entire filter medium dipping There is the mode of resin (for example, resin penetration is whole) to add.In Multilayer Network, individually resin can be added before combining layer Extremely each layer, or resin can be added to layer after combining layer.In some embodiments, resin for example passes through sprinkling Or any one of saturation dipping or the above method are added into fiber in dry state.In other embodiments, resin quilt It is added to wet layer.

As described above, in some embodiments, filter medium as described herein may include one or more modified layers. In general, can be used for layer surface and/or the internal any appropriate method being modified.In some embodiments, may be used By coating surface and/or inside at least part come to layer surface and/or inside be modified.In certain embodiments In, coating procedure includes to preformed fiber layer (for example, the preform by formation such as wet laying process, melt-blown process is fine Dimension net) in be introduced into the resin being dispersed in solvent or solvent mixture or material (for example, hydrophobic material, water wetted material).Coating The non-limiting example of method include using vapor deposition (for example, chemical vapor deposition, physical vapour deposition (PVD)), layer by layer deposition, Wax solidification, sol-gel process, channel mould coating machine (slot die coater), rotogravure application, silk screen coating, is applied self assembly Glue laminated squeezing coating (for example, double roller type or metering blade type size press coating machine), membrane pressure squeezing coat, blade coating, roller scraper coat, Air knife coating, roller coating, foam application, inverse roller coating, stick painting, curtain coating, composite coated (champlex coating), brushing, ratio You are scraper coating, short resident scraper coating (short dwell-blade coating), lip painting (lip coating), door roller coating It covers, the coating of door roller size press, laboratory size press coating, melt painting, dip-coating, rotor coating, spin coating, spraying (for example, EFI Apply), roller coating jaggy, roller transfer coating, liner saturation coating and saturation dipping.Other coating methods are also possible.? In some embodiments, uncompressed paint-on technique can be used that hydrophilic or hydrophobic material is applied on web.Uncompressed coating Technology can coat web, while not reduce the thickness of net substantially.In other embodiments, compression coating skill can be used Resin is applied on web by art.

In one group of embodiment, using chemical vapor deposition to the surface of layer as described herein and/or inside (for example, At least part on surface, the inside of layer and/or the entire layer of layer) to be modified may include chemical vapor deposited coatings.Changing It learns in vapor deposition, under the high level excitation of such as hot, microwave, UV, electron beam or plasma, is exposed to web and comes From gas or the gaseous reactant of liquid vapors, the gaseous reactant is deposited on web.Optionally, such as oxygen can be used The carrier gas of gas, helium, argon gas and/or nitrogen.

Other vapor deposition methods include aumospheric pressure cvd (APCVD), low-pressure chemical vapor deposition (LPCVD), Metal-organic chemical vapor deposition equipment (MOCVD), plasma auxiliary chemical vapor deposition (PACVD) or plasma enhancing Learn vapor deposition (PECVD), laser chemical vapor deposition (LCVD), photo chemical vapor deposition (PCVD), chemical vapor infiltration (CVI) and chemical beam epitaxy (CBE).

It is thin to deposit by being condensate in the expectation membrane material of evaporated form in substrate in physical vapour deposition (PVD) (PVD) Film.This method is related to physical process such as high-temperature vacuum vapor deposition and subsequent condensation or plasma sputtering bombardment, and non-chemical anti- It answers.

After applying coating to web, the dry coating of any suitable method can be passed through.Drying means it is unrestricted Property example include using light drier (photo dryer), infrared dryer, air oven, steam-heated cylinder or this The drier of field any suitable type well-known to the ordinarily skilled artisan.

In some embodiments, can coat (for example, modified) fiber at least part and substantially do not block up Fill in the hole of web.In some cases, essentially all of fiber can be coated and substantially not plugging hole.In some embodiment party In case, can be used method described herein (for example, by one or more of materials are dissolved and/or are suspended in a solvent with Form resin) hole with the resin of relative high weight percentage or material coating web without colmatation zone (for example, modified).

In general, any suitable material can be used to change the chemical property of layer (for example, modified) (for example, coming to the surface Learn property), and therefore change wetability.In some embodiments, material can be electrification.In some such embodiment party In case, the charge (for example, surface charge) of layer (for example, modified) further can promote to coalesce and/or moisturize from efficiency. For example, in certain embodiments, compared with the layer with uncharged hydrophilic modifying surface or unmodified surface, there is electrification The layer on hydrophilic modifying surface can have higher fuel-water separative efficiency and/or generate bigger coalescence drop.At other In embodiment, the charge (for example, surface) of layer (for example, modified) makes surface hydrophilic, but may not in addition promote to coalesce And/or it moisturizes from efficiency.

In general, the net charge of the modifying moieties (for example, surface, inside, entire layer) of layer can for it is negativity, positivity or in Property.In some cases, modified layer (for example, surface of layer) may include electronegative material and/or positively charged material.? In some embodiments, layer (for example, surface of layer) can be modified with neutral electrostatic characteristics material.It can be used for being modified layer The non-limiting example of material includes polyelectrolyte (for example, anion, cationic)；Oligomer；Polymer is (for example, complete Fluoroalkyl ethylmethyl acrylate, polycaprolactone, poly- [bis- (trifluoro ethoxy) phosphonitriles], the polymer with carboxylic moiety, Polymer, polyalcohol with amine moiety)；Small molecule (for example, containing carboxylate/salt monomer, with the polymerization of amine-containing monomer Object, polyalcohol)；Ionic liquid；Monomer precursor；Metal (for example, gold, copper, tin, zinc, silicon, indium, tungsten)；And gas, and combinations thereof.

In some embodiments, it can be used anionic polyelectrolyte to the surface and/or inside of layer (for example, modified) It is modified.For example, one or more of anionic polyelectrolytes can be sprayed or dip-coating to layer (for example, modified) at least It is on one surface and/or internal.The non-limiting example for the anionic polyelectrolyte that can be used for being modified surface includes poly- (2-acrylamido-2-methyl-1-propanesulfonic acid), poly- (2-acrylamido-2-methyl-1-propanesulfonic acid -co- acrylonitrile) gather (acrylic acid), poly- anetholesulfonic acid (polyanetholesulfonic), poly- (4- sodium styrene sulfonate), poly- (4- styrene sulphur Acid), poly- (4- styrene sulfonic acid), poly- (4- styrene sulfonic acid -co- maleic acid), poly- (vinylsulfuric acid ester/salt) and poly- (ethylene Base sulfonic acid, sodium), and combinations thereof.

In some embodiments, it can be used cationic polyelectrolyte to the surface and/or inside of layer (for example, modified) It is modified.Can be used for include to the non-limiting example on the surface of layer and/or the internal cationic polyelectrolyte being modified Diallyl dimethyl ammoniumchloride (PDDA), polyallylamine hydrochlorides, poly- (acrylamide -co- dimethylaminoethylacryl Acid esters/salt-methyl), poly- (acrylamide -co- diallyl dimethyl ammonium), P4VP and have ionization bone The ionene type amphipathic electrolyte of frame, and combinations thereof.

In other embodiments, modified layer may include for layer surface and/or it is internal be modified without Electric material.

In some embodiments, small molecule (for example, monomer, polyalcohol) can be used to come at least one surface to layer And/or inside is modified.For example, polyalcohol (for example, glycerol, pentaerythrite, ethylene glycol, propylene glycol, sucrose), one can be used First carboxylic acid, unsaturated dicarboxylic and/or small molecule containing one or more amine are modified at least one surface of layer. In certain embodiments, small molecule can be made to be deposited on layer (for example, modified) by coating (for example, chemical vapor deposition) On at least one surface.In some embodiments, regardless of method of modifying, on the surface of layer (for example, modified) and/or Internal small molecule can polymerize after deposition.

In certain embodiments, small molecule (such as monocarboxylic acid and/or unsaturated dicarboxylic (binary acid)) can be used To be modified at least one surface of layer.For example, in some cases, online ultraviolet polymerization can be used to make monocarboxylic acid And/or unsaturated dicarboxylic (binary acid) polymerize after deposit.It can be used for the unitary being modified at least one surface of layer The non-limiting example of carboxylic acid includes acrylic acid, methacrylic acid, crotonic acid, angelic acid, citronellic acid (cytronellic Acid), ricin acid (ricin acid), palmitoleic acid (palmitooleic acid), erucic acid, 4- vinyl benzoic acid, mountain Pears acid, geranic acid, linolenic acid and debydrogeranic acid, and combinations thereof.It can be used for being modified not at least one surface of layer The non-limiting example of saturated dicarboxylic acid (binary acid) includes that maleic acid, itaconic acid, acetylenedicarboxylic acid and maleic acid mono amide are sour, And combinations thereof.

In certain embodiments, small molecule can be amine-containing small molecule.Amine-containing small molecule can be primary amine, secondary amine or uncle Amine.In some such situations, amine-containing small molecule can be monomer.Can be used for layer (for example, modified) at least one The non-limiting example for the amine-containing small molecule (for example, amine-containing monomer) that surface is modified includes allylamine, 2- aminobenzene Based bisulfide, 4- aminophenyl propargyl ether, four formamide of 1,2,4,5- benzene, 1,2,4,5- benzene tetramine, 4,4 '-(1,1 '-connection Two oxygroup of benzene -4,4 '-diyl) diphenylamines, bis- (amino ethoxy) propane of 2,2-, the chloro- 3,5- diamino -2- pyrazine formyl of 6- The chloro- o-phenylenediamine of amine, 4-, 1,3- hexamethylene bis- (methylamines), 1,3- diamino benzylacetone, 1,4- diamino-anthraquinone, 4,4 '-diamino Benzanilide, 3,4- diaminobenzophenone, 4,4 '-diaminobenzophenones, 2,6- diamino -4- chlorine pyrimidine 1- oxidation Object, 1,5- diamino -2- methylpentane, 1,9- diamino nonane, 4,4 '-diamino octafluorobiphenyls, 2,6-diaminopurine, 2, 4- diaminotoluene, 2,6- diaminotoluene, the chloro- p-phenylenediamine of 2,5- bis-, 2,5- dimethyl -1,4- phenylenediamine, 2- dimethyl - 1,3- propane diamine, 4,9- dioxa -1,12- dodecamethylene diamine, 1,3-diaminopentane, 2,2 '-(ethylene oxygroup) bis- (second Amine), bis- (to the phenylene oxygen) diphenylamines of 4,4 '-(hexafluoroisopropyli,enes), 4,4 '-(hexafluoroisopropyli,ene) diphenylamines, 5,5 '- (hexafluoroisopropyli,ene) two ortho-aminotoluene, 4,4 '-(4,4 '-isopropylidene diphenyl -1,1 '-two oxygroup of diyl) diphenylamines, 4, 4 '-methylene-bis- (2- chloroaniline), 4,4 '-di-2-ethylhexylphosphine oxides (cyclohexylamine), 4,4 '-di-2-ethylhexylphosphine oxides (2,6- diethylaniline), 4, 4 '-di-2-ethylhexylphosphine oxides (2,6- dimethylaniline), 3,3 '-methylene dianiline (MDA)s, 3,4 '-oxygen diphenylamines, 4,4 '-(1,3- phenylenes Two isopropylidenes) dianil, 4,4 '-(1,4- phenylenediisopropylidene) dianils, 4,4 '-(two oxygroups of 1,3- phenylene) two Aniline, (1,4- butanediol) bis- (4-aminobenzoic acid ester) oligomer, 2,3,5,6- tetramethyl-p-phenylenediamine, 2,4,6- front three Base-m-phenylene diamine (MPD), 4,7,10- trioxa -1,13- tridecane diamine, three (2- amino-ethyl) amine, p dimethylamine, big ring are more Amine (cyclen), N, N '-diethyl -2- butene-1,4- diamines, N, N '-diisopropyl ethylenediamine, N, N '-diisopropyl -1,3- Propane diamine, N, N '-dimethyl -1,3- propane diamine, N, N '-diphenyl-p-phenylenediamine, 2- (amyl- 4- alkynyl) -2-Oxazoline, 1, 4,8,12- tetraazacyclododecane pentadecane, 1,4,8,11- tetraazacyclododecane tetradecane -5,7- diketone, 1- [bis- [3- (dimethylamino) third Base] amino] -2- propyl alcohol, 1,4- diazabicyclo [2.2.2] octane, 1,6- diamino hexane-N, N, N ', N '-tetraacethyl, 2- [2- (dimethylamino) ethyoxyl] ethyl alcohol, N, N, N ', N ", N "-five methyl diethylentriamine, N, N, N ', N '-tetraethyl- 1,3- propane diamine, N, N, N ', N '-tetramethyl -1,4- butanediamine, N, N, N ', N '-tetramethyl -2- butene-1,4- diamines, N, N, N ', N '-tetramethyl -1,6- hexamethylene diamine, 1,4,8,11- tetramethyl -1,4,8,11- tetraazacyclododecane tetradecane and 1,3,5- trimethyl Hexahydro -1,3,5-triazines, and combinations thereof.In certain embodiments, amine-containing monomer can spreading out for above-mentioned amine-containing small molecule Biological (for example, acrylamide), one or more functional group's (examples to form polymer can be reacted with other molecules by having Such as, unsaturated carbon-carbon bond).

In some embodiments, small molecule can be inorganic or organic hydrophobic molecule.Non-limiting example includes hydrocarbon (example Such as, CH₄、C₂H₂、C₂H₄、C₆H₆)；Fluorocarbon is (for example, CF₄、C₂F₄、C₃F₆、C₃F₈、C₄H₈、C₅H₁₂、C₆F₆)；Silane (example Such as, SiH₄、Si₂H₆、Si₃H₈、Si₄H₁₀)；Organosilan (for example, methyl-monosilane, dimethylsilane, triethylsilane)；Siloxanes (for example, dimethyl siloxane, hexamethyldisiloxane)；ZnS；CuSe；InS；CdS；Tungsten；Silicon carbide；Silicon nitride；Nitrogen oxidation Silicon；Titanium nitride；Carbon；Silicon-germanium；With alkyl-blocked hydrophobic acrylic class monomer and its halo derivatives (for example, 2- ethyl propylene Acetoacetic ester, methyl methacrylate, acrylonitrile).In certain embodiments, it is suitable to be modified for the surface to layer Hydrocarbon can have formula C_xH_y, wherein x is integer of 1 to 10, the integer that y is 2 to 22.In certain embodiments, for the table to layer The suitable silane that face is modified can have formula Si_nH_2n+2, any of them hydrogen can all be substituted into halogen (for example, Cl, F, Br, I), and wherein n is integer of 1 to 10.

As used herein, " small molecule " refer to naturally occurring or artificially generated (for example, passing through chemical synthesis) have phase To the molecule of low molecular weight.In general, small molecule is organic compound (that is, it contains carbon).Small organic molecule can contain more A carbon-carbon bond, stereocenter and other functional groups's (for example, amine, hydroxyl, carbonyl and heterocycle etc.).In certain embodiments, small The molecular weight of molecule is at most about 1000g/mol, at most about 900g/mol, at most about 800g/mol, at most about 700g/mol, extremely More about 600g/mol, at most about 500g/mol, at most about 400g/mol, at most about 300g/mol, at most about 200g/mol or extremely More about 100g/mol.In certain embodiments, the molecular weight of small molecule be at least about 100g/mol, at least about 200g/mol, At least about 300g/mol, at least about 400g/mol, at least about 500g/mol, at least about 600g/mol, at least about 700g/mol, extremely Few about 800g/mol or at least about 900g/mol or at least about 1000g/mol.The combination of above range is (for example, at least about 200g/mol and at most about 500g/mol) it is also possible.

In some embodiments, polymer can be used to be modified at least one surface of layer and/or inside.Example Such as, one or more of polymer can be applied to by paint-on technique in the surface of layer and/or at least part of inside.? In certain embodiments, polymer can be formed by monocarboxylic acid and/or unsaturated dicarboxylic (binary acid).In certain embodiments In, polymer can be graft copolymer and can be poly- in fiber and/or web by the way that polymer or oligomer to be grafted to It closes on object (for example, resinous polymer) and is formed.Graft polymers or oligomer may include that can be used in graft and fiber And/or the carboxy moiety of chemical bond is formed between the polymer in web.It can be used for being formed in fiber and/or web The non-limiting example of the polymer of graft copolymer includes polyethylene, polypropylene, polycarbonate, polyvinyl chloride, polytetrafluoroethyl-ne Alkene, polystyrene, cellulose, polyethylene terephthalate, polybutylene terephthalate (PBT) and nylon, and combinations thereof. It can be poly- by chemistry and/or radiochemistry (for example, electron beam, plasma, corona discharge, UV irradiate) method initiation grafting It closes.In some embodiments, polymer can be the polymer with the amine-containing repetitive unit of packet (for example, polyallylamine, poly- second Alkene imines gathersOxazoline).In certain embodiments, polymer can be polyalcohol.

In some embodiments, can be used gas at least one surface of layer (for example, modified) and/or it is internal into Row is modified.In some such situations, molecule in gas can on the surface of layer (for example, modified) material (for example, Fiber, resin, additive) oxygen content of the reaction to be formed in functional group (such as part of electrification) and/or increase layer surface.Official Can group non-limiting example include hydroxyl, carbonyl, ether, ketone group, aldehyde radical, acid groups, amide group, acetic acid esters/salt groups, Phosphate/salt groups, sulfite/salt groups, sulfuric ester/salt groups, amido, itrile group and nitro.It can be with layer (for example, modified ) the non-limiting example of gas of at least one surface reaction include CO₂、SO₂、SO₃、NH₃、N₂H₄、N₂、H₂, He, Ar and Air, and combinations thereof.

Fiber medium as described herein can be used for integral filter device or filter element.In some embodiments, one Or more extra play or component included together with filter medium (for example, be configured to comprising thin polymer short fiber Layer or the second layer are adjacent).The non-limiting example of extra play (for example, third layer, the 4th layer) includes meltblown layer, wet-laying Layer, spunbond layer, carded layer, airlaid layer, hydroentangled layer, power spin layer, centrifugal spinning layer or electrostatic spinning layer.In some embodiment party In case, can be stacked multiple layer by layer according to the thin polymer short fiber of the embodiment described herein, formed multilayer tablet with For medium or the element of worrying too much.

As described herein, in some embodiments, two or more layers of filter medium are (for example, comprising carefully polymerizeing The layer and the second layer of object staple fiber) it may be separately formed, and by any suitable method (for example, laminated, arrangement) or pass through It is combined using adhesive.Different process or same process can be used to be formed for two or more layers.For example, each layer can be independent Ground is by wet laying process, non-wet laying process (for example, melt-blown process, melt-spinning process, centrifugal spinning process, Static Spinning Silk technique, dry-laying process, air-laid process) or any other suitable method formed.

In some embodiments, two or more layers (for example, layer and the second layer comprising thin polymer short fiber) It can be formed by same process.In some cases, two or more layers are (for example, the layer comprising thin polymer short fiber And the second layer) can be formed simultaneously.

Different layers can be adhered to each other by suitable method.For example, each layer can on either side by adhesive that This adherency and/or each other melting engagement.Laminated and calendering process also can be used.In some embodiments, extra play can be by appointing The fiber or fiber blends of what type form via additional head box or coating machine and are suitably adhered to another layer.

Filter medium may include any appropriate number of layer, for example, at least 2 layers, at least 3 layers, at least 4 layers, at least 5 layers, extremely It is 6 layers, at least 7 layers few.In some embodiments, filter medium may include up to 20 layers.

In certain embodiments, filter medium may include one or more spies of the segment thickness through filter medium The gradient of property.For example, filter medium may include hydrophobicity or hydrophilic gradient.Such gradient can help to fluid separation (for example, fuel: water separation).In filter medium there is no in the part of gradient, which can through the part of net It is substantial constant.As described herein, in some cases, gradient is related to component (for example, the type of fiber is (such as thin polymerization Object staple fiber and/or fibrillating fibre), the material, additive, the adhesive that are modified for the surface to layer) cross filtering The different proportion of the thickness of medium.In some embodiments, component can be with the amount of another part different from filter medium Or concentration exists.In other embodiments, component is present in a part of filter medium, but is not present in filter medium Another part in.Other configurations are also possible.

In some embodiments, filter medium has one or more in two or more regions of the filter medium The gradient of multiple characteristics.E.g., including the filter medium of two layers can have the first gradient for a characteristic for crossing first layer And cross the second gradient of another characteristic of the second layer.First gradient and the second gradient in some embodiments can be identical, Or it in other embodiments can be different (for example, being characterized in that crossing the gradual change of the thickness property of filter medium and dash forward Become).Other configurations are also possible.

Suitable technique can be used in filter medium as described herein, such as uses wet laying process or non-wet-laying work Skill produces.In general, wet laying process includes mixing the fiber of one or more of seed types, for example, by a kind of The thin polymer short fiber of type is with another type of thin polymer short fiber and/or with different types of fiber (for example, closing At fiber and/or glass fibre) it mixes to provide fibre stuff.Slurry can be for for example based on aqueous slurry.At certain In a little embodiments, fiber is optional before being mixed together (for example, to realize a greater degree of uniformity in mixture) Ground is individually stored or is combined and is stored in different storage containers.

For example, simultaneously slurrying can be mixed together the first fiber in a vessel, and can be in a separate container by second Fiber mixing and slurrying.Then the first fiber and the second fiber combinations can be formed Single Fiber mixture together.It can be mixed Suitable fiber is handled via pulper before or after being combined.In some embodiments, it is being blended in The composition of fiber is handled via pulper and/or storage container before together.It is appreciated that can also be into mixture Introduce other components.Furthermore, it is to be understood that the composition of other fiber types can be used in fibre blend, such as herein The fiber type.

In certain embodiments, formed by wet laying process includes two or more layers (such as comprising carefully gathering Close object staple fiber and the second layer) medium.For example, can be by packet fibrous first in solvent (for example, aqueous solvent such as water) Dispersion (for example, slurry) be applied on the net conveyor of paper machine (for example, fourdrinier machine or rotoforming paper machine) with Form the first layer loaded by the net conveyor.While the deposited thereon first layer or later by solvent (for example, aqueous molten Agent such as water) in fibrous second dispersion (for example, another slurry) of packet be applied on first layer.Continue during the above process Ground applies vacuum to the first fiber dispersion and the second fiber dispersion to remove solvent from fiber, so that generating includes first The product of layer and the second layer.Then the dry product being consequently formed, and if it is necessary, by using known method into one Step handles (for example, calendering) to form multiple layer filter media.In some embodiments, such processing can produce across two Or more at least one characteristic of the thickness of layer gradient.

Any suitable method can be used to form slurry.In some embodiments, other add is added into slurry Add agent to help to process.It can also be the temperature was then adjusted to OK range, for example, 33 °F to 100 °F (for example, 50 °F to 85 °F). In some cases, the temperature of slurry is kept.In some cases, temperature is not adjusted actively.

In some embodiments, wet laying process use equipment similar with conventional paper technology, for example, waterpower is broken Pulp grinder, forming machine or head box, drier and optional converter.As described above, can be made in one or more pulpers Standby slurry.Slurry pumping can suitably be entered in head box after mixed slurry in pulper, slurry can be in head box With or can not be with other slurry compositions.It can add or can not add other additives.It also can be used other water by slurry Dilution so that the ultimate density of fiber in the appropriate range, for example, about 0.1 weight % to about 0.5 weight %.

Wet laying process may be particularly useful in filter medium filter medium for example as described herein formed one or The gradient of more characteristics.For example, in some cases, identical mashing pump is sent into individual head box to form filtering Different layers and/or gradient in medium.In other cases, two or more different mashing pumps can be sent into individual Layer and/or gradient different in filter medium are formed in head box.In other embodiments, first layer can be formed simultaneously And the second layer can be formed on the top, it drains and dry.

In some cases, the pH of fibre stuff can be adjusted as needed.For example, the fiber of slurry usually can be in neutral item Disperse under part.

Before slurry is sent into head box, optionally make slurry by centrifugal cleaner and/or pressurized screen to remove Remove unfiberized material.Can make or can not make slurry by other equipment (for example, refiner or fluffer) with into The dispersion of one step raising fiber.For example, fluffer can be used for smoothly or removing may be in the arbitrary point during fibre stuff formation Locate the block or protrusion that occur.Then it can be used any suitable equipment (for example, fourdrinier machine, rotoforming paper machine, circle Net paper machine or inclined wire fourdrinier machine) fiber is collected in sieve or online with rate appropriate.In some cases, Ke Yi Wet laid layer is formed on non-wet laid layer (for example, scrim).

As described herein, in some embodiments, to layer (for example, the preformed layer formed by wet laying process) Add resin.For example, make layer along suitable sieve or Netcom out-of-date, different groups for will including in resin using suitable technology (for example, polymer adhesive, acid scavenger and/or other components) (it can be individual emulsion form) is divided to be added to fiber Layer.In some cases, each component of resin is mixed into lotion before combining with other components and/or layer.Using example As the component for including in resin is pulled through layer by gravity and/or vacuum.In some embodiments, it can be diluted and be set with softened water One of component for including in rouge or more is simultaneously pumped in fibrous layer.It in some embodiments, can be by fiber pulp Resin is applied in fibre stuff by material before being introduced into head box.For example, resin can be introduced to (for example, injection) fibre stuff In and impregnate fiber and/or be deposited on fiber.In some embodiments, solvent saturation process (solvent can be passed through Saturation process) resin is added to layer.

In other embodiments, using non-wet laying process (for example, dry-laying process, air-laid process, Spinning technique such as electrostatic spinning or centrifugal spinning, melt-blown process) form all or part of filter medium (for example, second Layer).For example, in some embodiments, can be blown to synthetic fibers on conveyer belt by air in air-laid process, Then apply resin.In some embodiments, in carding process, pass through roller before applying adhesive and connect with the roller Prolongation (for example, hook, needle) operate fiber.It in some cases, can be more applicable by non-wet laying process forming layer In the highly porous medium of production.As described above, it is dry to impregnate (for example, by saturation, sprinkling etc.) with any suitable resin Layer.

In certain embodiments, the entitled " Meltblown that can be submitted such as on November 7th, 2008 by melt-blown systems Entitled " the Fine Fiber that the U.S. Publication of Filter Medium " the 2009/0120048th and on December 17th, 2010 submit Melt-blown systems forming layer described in U.S. Publication the 2012-0152824th of Filter Media and Processes " (for example, second layer), wherein each piece is incorporated herein by reference in their entirety for all purposes.In certain embodiments, may be used Pass through melt-spun work or centrifugal spinning process forming layer (for example, second layer).In some embodiments, non-wet-laying can be used Technique (such as air-laid process or carding process) comes forming layer (for example, second layer).For example, in air-laid process, Synthetic fibers can be mixed and simultaneously blow to air on conveyer belt.In some embodiments, in carding process, by roller and Prolongation (for example, hook, needle) the operation fiber being connect with the roller.In some cases, it is formed by non-wet laying process Layer can be more suitable for producing highly porous medium.As described above, can be impregnated with any suitable resin (for example, by being saturated, Sprinkling etc.) layer.In some embodiments, can be used non-wet laying process (for example, melt-blown, electrospinning) come forming layer (for example, The second layer), and wet laying process can be used to form another layer (for example, first layer).Any suitable method can be used (for example, laminated, total pleating or arrangement) carrys out combination layer.

During or after filter medium formation, filter medium can be further processed according to various known technologies.For example, can Resin is included in filter medium using coating method.It is optionally possible to use the side of such as laminated, total pleating or arrangement Method forms extra play and/or extra play is added to filter medium.For example, in some cases, by as described above wet Two layers (for example, thin short fiber layers and second layer) is formed as composite article by method net-forming process, then by any suitable Method (for example, laminated, total pleating or arrangement) combines the composite article with third layer.It is appreciated that can not only be based on each layer Component but also the filterings with feature as described herein can be formed using multiple layers of different characteristics according to appropriately combined The effect of medium come suitably customize by process as described herein formed filter medium or composite article.

In some embodiments, be further processed may include being pleated to filter medium.For example, total pleating methods can be passed through Engage two layers.In some cases, filter medium folding can be given by forming scribing line with the spacing appropriate that is spaced each other Filter medium or its each layer are suitably pleated.In some cases, filter medium can be surrounded to core around each other, or Person can be by a layer around the layer of pleating.It should be understood that any suitable pleating technology can be used.In some embodiment party In case, filter medium can be post-processed, such as carry out corrugation processing to increase the surface area in net.In other implementations In scheme, filter medium can be embossed.

It should be understood that filter medium may also include other parts in addition to one or more layers described herein.Some In embodiment, it is further processed including being incorporated to one or more structure features and/or reinforcing element.For example, can will filter Medium is combined with additional structural features (for example, polymer mesh and/or metallic mesh).In one embodiment, may be used Sieve backing is arranged on filter medium, bigger rigidity is provided.In some cases, sieve backing can help to keep beating The construction of pleat.For example, sieve backing can be the metal mesh of extension or the plastic wire of extrusion.

In some embodiments, layer as described herein can be nonwoven web.Nonwoven web may include No yield point fiber (example Such as, the random packing of fibers in net).The example of nonwoven web includes passing through wet laying process as described herein and non-wet process Net made of net-forming process.Nonwoven web may also include paper such as based on the net of cellulose.

In some embodiments, filter medium can be incorporated in various filter element to be used for a variety of filtration applications. The filter of exemplary types includes fuel filter (for example, motor vehicle fuel filter), movable hydraulic roof filter, hydraulic work Industry filter, oil strainer (for example, lubricating oil filter or HD lubricating oil filter), chemical process filters, industrial department Manage filter, medical filter (for example, blood filter), air filter and water filter.In some cases, this paper institute The filter medium stated may be used as coalescer filter medium.Filter medium is applicable to filtering gas or liquid.

In some embodiments, filtering medium layer can be pleated, is wound with core or without core, wound on for example firing Around the medium for expecting the pleating in water spacer.In certain embodiments, it can will collect bowl or other suitable components are arranged In both the upstream, downstream or upstream and downstream of medium.Collecting bowl is that/separation/is fallen off from medium after coalescing for collecting Water container.Collecting bowl can be a part of filter element or filter housings.

Layer disclosed herein comprising thin polymer short fiber and/or filter medium can be incorporated to various filter element with For a variety of applications, including hydraulic filtering is applied and non-hydraulic filtration application includes fuel applications, lubricating oil application, air applications Deng.

Filter element can also be any suitable form, such as filter, bellows, spiral wound element, the plate of pleating Frame device, plain film module, container bag, disc type pipe unit, radial filter element, panel-style filter element or slot fluid element (channel flow element).Radial filter element may include the open file mesh for being limited in two cylindrical shapes Interior pleating filter media.During use, fluid can flow to the inside of radial members from outside by the medium of pleating.

Embodiment

Certain embodiments that following embodiment is intended to illustrate the present invention, but should not be construed as limiting of the invention whole A range and entire scope of the invention is not illustrated.

Embodiment 1

This embodiment describes the double medium filtration medium that four include first layer and the second layer, first layer includes 100 weights Measure hydrophobic polyetherimide (PEI) staple fiber of average diameter less than or equal to about 1 micron of %.Filter medium 1 and 2 includes packet The second layer of containing cellulose paper pulp fiber and polyester fiber, and only in the fixed again upper difference of first layer.Filter medium 3 and 4 wraps The second layer of the synthetic fibers comprising 100 weight % is included, and only in the fixed again upper difference of first layer.First layer was for increasing The particulate efficiency and/or fuel of filter medium: water separative efficiency, and do not increase the thickness of filter medium substantially, and do not use Glass fibre.The filter medium with include the second layer identical with filter medium 1 to 4 and glass fibre comprising 0 weight % The filter medium of the first meltblown layer compare, there is relatively high fuel: water separative efficiency and/or particulate efficiency.

Double medium filtration medium is made using laboratory handsheet mold.To be used in blender the fiber of the second layer with 1000mL water mixes 2 minutes.Slurry is placed in handsheet mold, and is forming web on the net.Web is drained And it is dry.Then web is put back in handsheet mold, and another slurry for being used to form first layer is placed in the handmade paper It is shaped in mold and on the top of the second layer.Gained web is drained and dried.For filter medium 1 and 2, gained Web includes the second layer comprising cellulose pulp and polyester fiber and the first layer comprising thin PEI staple fiber.For filtering Medium 3 and 4, gained filter medium include comprising 100% synthetic fibers the second layer and comprising thin PEI staple fiber first Layer.

For filter medium 1 and 2, addition be for the ratio that the amount of the material of the second layer is 10.91g [10:37:47:5: 1] Prince George paper pulp, Porosanier paper pulp, Suzano paper pulp, polyester (7.16 microns of diameter, length 3.125mm) and kuralon SPG-056 vinal, for the material of first layer, (diameter is less than 1 micron and long for addition Spend about 1mm 100%PEI staple fiber) amount be 3.03g.For filter medium 3 and 4, amount of the addition for the material of the second layer It is fibrillation acrylic compounds paper pulp (Canadian Standard Freeness 250ml) that ratio for 10.9g is 26:21:36:16:1, poly- Ester fiber (Teijin, 7.4 microns of diameter, length 5mm), polyester fiber (12.5 microns of diameter, length 5mm), polyester (diameter 7.2 microns, length 3.125mm) and kuralon SPG-056 vinal.For the material of first layer, (diameter is small for addition In 1 micron and the 100%PEI staple fiber of length about 1mm) amount be 3.03g.

For all filter mediums, scrim layer is bonded on the surface for the first layer of top layer, is used to support.Filtering is situated between The weight of determining of the first layer of matter 2 and 3 is 10 pounds per reams of (16g/m²).The weight of determining of the first layer of filter medium 1 and 4 is 20 pounds per reams ((33gsm).In all filter mediums, the weight of determining of the second layer is 72 pounds per reams of (116g/m²).For filter medium 1 and 2, The weight of determining of scrim is 27 pounds per reams of (44g/m²).For filter medium 3 and 4, the weight of determining of scrim is 18 pounds per reams of (29g/m²)。

As the medium for control, form such filter medium comprising determine weight be 20 pounds per reams (33gsm) and The first meltblown layer that avarage fiber diameter is about 3 microns, first meltblown layer be laminated to as described above for filter medium 1 to 4 are formed by the second layer.

The multi-pass for determining efficiency and dust containing capacity has been carried out as described above filters test.Use SAEJ1488 standard (2010) the average fuel water separative efficiency and initial fuel water separative efficiency of filter medium are determined.Standard testing fluid reaches for 15 Cause/cm.

Table 1 shows the various structures characteristic of filter medium 1 to 4.For filter medium 1 and 2, the water contact angle of the second layer It is 110 °, and the water contact angle of thin PEI short fiber layers is 128 °.For filter medium 3 and 4, the water contact angle of the second layer is 115 °, and the water contact angle of thin PEI short fiber layers is 128 °.Therefore, in all filter mediums, first layer is more than the second layer It is hydrophobic.

Table 1. includes the characteristic of the filter medium of thin polymer short fiber

The embodiment shows by including that final particulate efficiency may be implemented in the two-layered medium of thin short fiber layers and the second layer Be greater than 95% and/or average fuel greater than 95%, primary particles efficiency: water separative efficiency is free of glass more than or equal to 60% Filter medium.Low interfacial tension condition is realized by the addition hydrophobicity thin short fiber layers bigger than the hydrophobicity of the second layer Relatively high water separative efficiency under (15 dynes/cm to 19 dynes/cm).It is low since drop size depends on interfacial tension Interfacial tension condition is (for example, relatively small less than about 20 dynes/cm) generation diameter is relatively difficult to isolated drop.The embodiment Show that the two-layered medium comprising thin polymer short fiber may be implemented higher compared with determining weight and the similar melt blown media of thickness Average grain efficiency and primary particles efficiency and equal or higher average water separative efficiency and initial water separative efficiency.

Embodiment 2

This embodiment describes two double medium filtration media with relatively high particulate efficiency, the two double medium filtrations are situated between Matter includes less than or equal to about 1 micron and short less than the cellulose acetate (CA) of the PEI fiber in embodiment 1 comprising average diameter The second layer of the first layer of fiber and the synthetic fibers comprising 100 weight %.Filter medium 5 and 6 includes comprising cellulose acetate The first layer of staple fiber, and only in the fixed again upper difference of first layer.

Double medium filtration medium is made using laboratory handsheet mold.To be used in blender the fiber of first layer with 1000mL water mixes 2 minutes.Slurry is placed in handsheet mold, and is forming web on the net.Web is drained And it is dry.Then web is put back in handsheet mold, and the second slurry is placed in handsheet mold and in first layer It is shaped on top.Gained web is drained and dried.Gained web includes all comprising synthetic fibers blend The weight of determining of the second layer and first layer comprising CA staple fiber, the two different top layers is 16.28gsm and 32.55gsm.Addition is used The fibrillation acrylic compounds paper pulp (Canadian standard for being 26:21:36:16:1 in the ratio that the amount of the material of the second layer is 10.9g Freedom is 250ml), polyester fiber (Teijin, 7.4 microns of diameter, length 5mm), polyester fiber (12.5 microns of diameter, it is long Spend 5mm), polyester (7.2 microns of diameter, length 3.125mm) and kuralon SPG-056 vinal.Addition is for the The total amount of one layer of material is respectively 1.51g and 3.03g so that 16.28gsm (filter medium 5) and 32.55gsm (filtering Jie is made Matter 6) layer.Scrim is laminated on the surface of first layer, is used to support.

Efficiency and dust containing capacity test are carried out as described in example 1 above.The various structures that table 2 shows filter medium 5 to 6 are special Property.

Table 2. includes the characteristic of the filter medium of thin polymer short fiber

The embodiment shows by including that final particulate efficiency may be implemented in the two-layered medium of thin short fiber layers and the second layer The filter medium without glass greater than 99.9%.

Embodiment 3

This embodiment describes three double medium filtration media with relatively high particulate efficiency, these three double medium filtrations are situated between Matter includes the blend comprising the average diameter hydrophilic synthetic staple less than or equal to about 1 micron and hydrophobic synthetic staple The second layer of first layer and the synthetic fibers comprising 100 weight %.The filter medium only acetate fiber used in first layer It is different in the ratio of plain staple fiber and polyetherimide staple fiber.The average diameter of cellulose acetate staple fiber compares polyetherimide Staple fiber it is small.

Double medium filtration medium is made using laboratory handsheet mold.To be used in blender the fiber of first layer with 1000mL water mixes 2 minutes.Slurry is placed in handsheet mold, and is forming web on the net.Web is drained And it is dry.Then web is put back in handsheet mold, and the second slurry is placed in handsheet mold and in first layer It is shaped on top.Gained web is drained and dried.Gained web includes all comprising synthetic fibers blend The second layer and in varing proportions such as 1:3,1:1 and 3:1 (that is, being filter medium 7, filter medium 8 and filter medium 9 respectively) packet The first layer of staple fiber containing PEI and CA staple fiber.Ratio of the addition for the amount of the material of the second layer to be 10.9g is 26:21: Fibrillation acrylic compounds paper pulp (Canadian Standard Freeness 250ml), polyester fiber (Teijin, the diameter 7.4 of 36:16:1 Micron, length 5mm), polyester fiber (12.5 microns of diameter, length 5mm), polyester (7.2 microns of diameter, length 3.125mm) and Kuralon SPG-056 vinal.Total amount of the addition for the material of first layer (depends on PEI and cellulose acetate Ratio) be 3.03g.Scrim is laminated on the surface of first layer, is used to support.

Efficiency and dust containing capacity test are carried out as described in example 1 above.The various structures that table 3 shows filter medium 7 to 9 are special Property.

Table 3. includes the characteristic of the filter medium of thin polymer short fiber

The embodiment shows by including that the two-layered medium of thin short fiber layers and the second layer may be implemented to low interfacial tension The final particulate efficiency of fluid is greater than 99.5%, primary particles efficiency and is greater than 99.55% and average fuel: water separative efficiency is greater than Or the filter medium without glass equal to 60%.

Embodiment 4

This embodiment describes double medium filtration medium be designed to further increase dust containing capacity and fuel: water separates another The combination of filter layer.

To in embodiment 3 filter medium 9 and 100gsm polybutylene terephthalate (PBT) (PBT) meltblown layer carry out it is whole Reason.Efficiency and dust containing capacity test are carried out as described in example 1 above.Table 4 shows the various structures characteristic of filter medium 10.

Table 4. includes the characteristic of the filter medium of thin polymer short fiber and meltblown layer

Meltblown layer further improves the dust containing capacity and fuel of double medium filtration medium: water separative efficiency.

It is described several aspects of at least one embodiment of the invention, it should be appreciated that art technology By easy progress various changes, modification and improvement for personnel.It such changes, modifications and improves it is intended that present disclosure A part, and be intended within the spirit and scope of the present invention.Therefore, foregoing description and attached drawing are only example.

Claims

1. a kind of filter medium, comprising:

First layer, the first layer include avarage fiber diameter less than or equal to about 3 microns and average length less than or equal to about More than first polymer short fiber of 10cm；

The second layer, the second layer include fiber of the avarage fiber diameter greater than or equal to about 4 microns；And

Third layer, wherein the third layer is non-wet laid layer,

Wherein at least one surface of the first layer, the second layer and the third layer is surface modification, and

Wherein the air penetrability of the filter medium is 0.3CFM to 300CFM, and determining weight is 5g/m²To 1000g/m²。

2. a kind of filter medium, comprising:

Modified layer, the modified layer include avarage fiber diameter less than or equal to about 1 micron and average length less than or equal to about More than first polymer short fiber of 10cm, wherein the thickness of first layer is less than or equal to about 0.2mm；And

The second layer, the second layer includes fiber of the avarage fiber diameter greater than or equal to about 4 microns, wherein the filter medium Dry Mullen burst strength be 0.5psi to 200psi.

3. a kind of filter medium, comprising:

Modified layer, the modified layer include more than first piece polymer short fiber peace of the average diameter less than or equal to about 1 micron Equal diameter is less than or equal to 1 micron of more than second polymer short fiber, and wherein the water contact angle of first layer is about 30 degree to 165 Degree；And

The second layer, the second layer includes fiber of the average diameter greater than or equal to about 4 microns, wherein the filter medium is saturating Gas rate is 0.3CFM to 300CFM, and determining weight is 5g/m²To 1000g/m²。

4. a kind of filter medium, comprising:

First layer, the first layer include avarage fiber diameter less than or equal to about 1 micron and average length less than or equal to about More than first polymer short fiber of 10cm；

Second non-wet laid layer, the second non-wet laid layer include avarage fiber diameter greater than or equal to about 4 microns Fiber；And

Mesh layer.

5. filter medium according to any preceding claims, wherein the thickness of the first layer less than or equal to about 0.2mm。

6. filter medium according to any preceding claims, wherein the first layer includes greater than or equal to about 50 weights Measure more than first polymer short fiber of %.

7. filter medium according to any preceding claims, wherein the water contact angle of the first layer greater than or equal to about 35 degree and less than or equal to about 165 degree.

8. filter medium according to any preceding claims, wherein the water contact angle of the first layer greater than or equal to about 90 degree.

9. filter medium according to any preceding claims, wherein the water contact angle of the second layer is less than about 90 degree.

10. according to claim 1, filter medium described in 2 or 4 to 9, wherein more than first polymer short fiber is averaged Diameter is less than or equal to about 0.5 micron.

11. filter medium according to any preceding claims, wherein the average diameter of the fiber of the second layer is greater than Or equal to about 5 microns and less than or equal to about 15 microns.

12. filter medium according to any preceding claims, wherein the first layer determines weight greater than or equal to about 5g/ m²And less than or equal to about 100g/m²。

13. filter medium according to any preceding claims, wherein the second layer includes continuous fiber.

14. filter medium according to any preceding claims, wherein the second layer includes synthetic fibers.

15. filter medium according to any preceding claims, wherein the pressure drop of the filter medium less than or equal to about 50kPa。

16. filter medium according to any preceding claims, wherein the air penetrability of the filter medium is less than or equal to About 300CFM.

17. filter medium according to any preceding claims, wherein the primary particles efficiency of the filter medium is greater than Or it is equal to about 80%.

18. filter medium according to any preceding claims, wherein the fuel of the filter medium: water separative efficiency is big In or equal to about 30%.

19. filter medium according to any preceding claims, wherein the thickness of the filter medium less than or equal to about 30mm。

20. filter medium according to any preceding claims, wherein the filter medium determine weight less than or equal to about 1000g/m²。

21. filter medium according to any preceding claims, wherein the first layer includes about 0 weight % to about 1 weight Measure the glass fibre of %.

22. filter medium according to any preceding claims, wherein the second layer includes about 0 weight % to about 1 weight Measure the glass fibre of %.

23. filter medium according to any preceding claims, wherein the filter medium includes about 0 weight % to about 1 The glass fibre of weight %.

24. a kind of filter element, including filter medium according to any preceding claims.

25. filter medium according to any preceding claims, wherein the first layer includes that more than second polymer is short Fiber.

26. filter medium according to any preceding claims, wherein more than first polymer short fiber is averaged Diameter is less than or equal to about 0.5 micron.

27. filter medium according to any preceding claims, wherein more than first polymer short fiber by than with It is formed in the more hydrophobic material of the material for forming more than second polymer short fiber.

28. filter medium according to any preceding claims, wherein more than first polymer short fiber by than with It is formed in the more hydrophilic material of the material for forming more than second polymer short fiber.

29. filter medium according to any one of claim 2 to 4, wherein more than first polymer short fiber by Water wetted material is formed.

30. filter medium according to any preceding claims, wherein more than first polymer of the first layer Staple fiber is formed by the hydrophobicity material bigger than the hydrophobicity of the second layer.

31. filter medium according to any preceding claims further includes third layer.

32. filter medium according to any preceding claims, wherein the third layer is meltblown layer.

33. filter medium according to any preceding claims, wherein the third layer is non-fibrous layer.

34. filter medium according to any preceding claims, wherein the third layer is mesh.