Technical field
[0001]
　The present invention is excellent in collecting performance, hardly clogged with low pressure loss, to pay off excellent filter cloth and a manufacturing method thereof and a bag filter for bag filter in property.
Background technique
[0002]
　Dust collector is provided with a flat filter cloth that is sewn into a cylindrical shape (bag filter). The dust collector, a powder (dust) to the dust collecting target according filtration cloth filter cloth surface primary deposition, after collecting, and flicked the powder was collected by pulsing the filter cloth.
[0003]
　Such filter cloth, low pressure loss, it is desired that excellent Katsume clogging without 払落 and resistance at high collection efficiency, thus far, various filter cloth have been proposed. For example, the fiber layer of the filter cloth surface that a dense structure, such as those with layered structure of fine fibers have been proposed to filter cloth surface (e.g., see Patent Documents 1-3).
[0004]
　However, excellent collection performance, less likely to be clogged with a low pressure loss, filter cloth for bag filter was excellent in brushing property has not been much proposed so far.
CITATION
Patent Literature
[0005]
Patent Document 1: JP-A-9-187611 JP
Patent Document 2: JP-A 9-313832 Patent Publication
Patent Document 3: JP 2000-140530 JP
Summary of the Invention
Problems that the Invention is to Solve
[0006]
　The present invention has been made in consideration of the above situation, and its object is excellent collection performance, hardly clogged with low pressure loss, dust removal properties superior bag filter for filter cloth and a manufacturing method thereof and also It is to provide a bag filter.
Means for Solving the Problems
[0007]
　The present inventors have result of intensive investigations to achieve the above object, a nonwoven fabric comprising ultrafine fibers having a specific fiber diameter, by laminating a base fabric, excellent collection performance, clogging at low pressure loss difficult, it found that the filter cloth for bag filter was excellent in brushing can be obtained, and have completed the present invention by overlaying a further intensive study.
[0008]
　Thus, a filter cloth for bag filter comprising a "non-woven fabric and the base fabric according to the present invention,
　the nonwoven fabric, filter cloth for bag filter, wherein the fiber diameter D includes ultrafine fibers of 200 ~ 2000 nm . "it is provided.
[0009]
　At that time, in the ultrafine fiber is preferably L / D ratio of fiber length L to the fiber diameter D is within the range of 100 to 2,500. Further, it is preferable that the ultrafine fiber is a polyester fiber or polyphenylene sulfide fiber. Further, in the polyester fibers, it is preferable elongation is 60% or less than 60%. Further, it is preferable that the ultrafine fibers on the nonwoven fabric is contained 3-50 wt%. Further, it is preferable that the nonwoven fabric is a spun lace nonwoven fabric. Further, the nonwoven fabric is preferably has a multilayer structure. Also, the basis weight in the nonwoven fabric is 10 ~ 90 g / m 2 is preferably in the range of. Further, it is preferable that the thickness in the non-woven fabric is in the range of 0.2 ~ 0.6 mm. Further, it is preferable that the porosity is in the range of 90 to 97% in the nonwoven fabric. Further, the base fabric, basis weight 40 ~ 120 g / m 2 comprising a scrim is preferably a needle-punched nonwoven. The base fabric is, basis weight 100 ~ 400 g / m 2 is preferably a spunbonded nonwoven.
[0010]
　Further, according to the present invention, after the fiber diameter D to obtain ultrafine fibers of 200 ~ 2000 nm by dissolving and removing the sea component of the formed sea-island type composite fiber with a sea component and the island component, the ultrafine fibers to obtain a nonwoven fabric using, laminating the nonwoven to a substrate, method of manufacturing the filter cloth for the bag filter is provided.
[0011]
　Further, according to the present invention, by using a filter cloth for the bag filter, bag filter the spun lace nonwoven fabric is arranged on the dust inlet side is provided. At that time, it is preferable that by performing sewing or pleating.
Effect of the invention
[0012]
　According to the present invention, excellent collection performance, hardly clogged with low pressure loss, the dust removal excellent filter cloth and a manufacturing method thereof and a bag filter for bag filter also can be obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013]
In [1] the present invention, it is a view schematically showing a state in which the nonwoven fabric is arranged on the dust inlet side. The arrows indicate the traveling direction of the dust.
DESCRIPTION OF THE INVENTION
[0014]
　It will be described in detail embodiments of the present invention. Microfine fiber in the present invention is 200 ~ 2000 nm (preferably 200 ~ 1000 nm, more preferably 400 ~ 800 nm) having a fiber diameter D of. 該繊 fiber diameter D is a single fiber diameter of microfine fibers. 該繊 fiber diameter may be reduced is large and the collection performance than 2000 nm. Conversely, 該繊 fiber diameter is likely to have low dispersibility of ultrafine fibers than 200nm decreases the collection performance decreases.
[0015]
　Fiber diameter of the can with a transmission electron microscope TEM, can be measured by photographing a single fiber cross-section photograph magnification of 30,000. At that time, the TEM has a length-measuring function can be measured by utilizing the length measurement function. In addition, in the absence of the length measurement function TEM, to expand copy the photos taken, may be measured by a ruler in consideration of the scale.
[0016]
　At that time, if the cross-sectional shape of the single fiber is a modified cross-section other than round cross-section, the fiber diameter is assumed to use a diameter of the circumscribed circle of the cross section of single fiber.
[0017]
　The microfine fibers may be long fibers, but short fibers are preferred for obtaining an excellent collection performance to enhance the dispersibility. At that time, it is preferable as the fiber length (cut length) is in the range of 0.3 ~ 20 mm. Further, it is preferable that a ratio L / D of the fiber length L to the fiber diameter D 200 ~ 4000 (more preferably 800 to 2500) in the range of. The ratio between L / D is smaller than 200 entanglement among the fibers by high-pressure water may be reduced. Conversely, collecting performance and strength become cohesive fiber mass Dispersible poor and the ratio L / D is greater than 4000 may be reduced.
[0018]
　The is not particularly limited as the fiber type of ultrafine fiber preferably polyester fibers or polyphenylenesulfide (PPS) fibers.
[0019]
　The polyester for forming the polyester fibers, polyethylene terephthalate (hereinafter also referred to as "PET".), Polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, to these as the main repeating unit, and isophthalic acid 5- aromatic dicarboxylic acids and adipic acid such as sulfoisophthalic acid metal salts, hydroxycarboxylic acid condensate, diethylene glycol and trimethylene glycol and aliphatic dicarboxylic acid and ε- caprolactone sebacic acid, tetramethylene glycol, and hexamethylene glycol copolymers of glycol component and the like are preferable. Polyester and which are material recycling or chemical recycling, as described in JP 2009-091694, biomass i.e. it may be a polyethylene terephthalate obtained by using a monomer component obtained material of biological origin as raw materials. Furthermore, as described in JP 2004-211268 and JP 2004-270097 JP, or a polyester obtained by using a catalyst containing a specific phosphorus compound and titanium compound.
[0020]
　Further, the polyester fibers are drawn yarn, undrawn yarn may be either semi-drawn yarn. Further, to elongation may be less than 60% or 60% or more. Incidentally, the polyester drawn yarn is usually elongation is less than 60%, polyester undrawn yarn is usually, elongation of 60% or more.
[0021]
　The polyphenylene sulfide (PPS) polyarylene sulfide resin to form fibers, any one may be used as long as it belongs to the called category polyarylene sulfide resin. The polyarylene sulfide resin, as a structural unit, for example, p- phenylene sulfide unit, m- phenylene sulfide unit, o- phenylene sulfide units, phenylene sulfide sulfone units, phenylene sulfide ketone units, phenylene sulfide ether unit, diphenylene sulfide units , substituent-containing phenylene sulfide unit, branched structure-containing phenylene sulfide unit, can be mentioned those consisting etc. among them, p- phenylene sulfide units 70 mol% or more, those containing particularly 90 mol% or more preferably, further poly (p- phenylene sulfide) is more preferable.
[0022]
　Further, the port polyphenylene sulfide fibers drawn yarn, undrawn yarn may be either semi-drawn yarn. Further, to elongation may be less than 60% or 60% or more. Incidentally, polyphenylene sulfide drawn yarn is usually, elongation is less than 60%, polyphenylene sulfide undrawn yarn is usually, elongation of 60% or more.
[0023]
　Method for producing the ultrafine fiber is not particularly limited, the methods disclosed in WO 2008/130019 pamphlet is preferable. That, and the island components made of fiber-forming thermoplastic polymer, tends polymer was dissolved in an alkali aqueous solution than the fiber-forming thermoplastic polymer consisting of (hereinafter. Also referred to as "readily soluble polymer") subjected to alkali reduction processing to the composite fibers having a sea component is preferably obtained by dissolving and removing the sea component.
[0024]
　Here, the alkali aqueous solution readily soluble polymer that forms the sea component, the dissolution rate ratio fiber-forming thermoplastic polymer forming the island components is 200 or more (preferably 300 to 3000), good island separability next preferred.
[0025]
　The easily soluble polymer to form the sea component, particularly good polyesters of fiber-forming, aliphatic polyamides, can be mentioned as preferred examples of polyolefins such as polyethylene and polystyrene. Taking further examples, polylactic acid, ultrahigh molecular weight polyalkylene oxide condensation polymer, copolyesters of polyalkylene glycol compound and 5-sodium sulfoisophthalic acid is preferably more soluble in an alkali aqueous solution. Here, the alkali aqueous solution, potassium hydroxide, refers to such as sodium hydroxide solution. In addition to this, and the sea component, as the combination of the solution which dissolves the 該海 components, formic acid to aliphatic polyamides such as nylon 6 and nylon 66, trichlorethylene for polystyrene and polyethylene (especially high-pressure low-density polyethylene and linear hydrocarbon solvents hot toluene and xylene for Jo low density polyethylene), the hot water for polyvinyl alcohol or ethylene-modified vinyl alcohol-based polymer can be cited as an example.
[0026]
　Among the polyester polymer, 5-sodium sulfoisophthalic acid 6-12 mol% and a molecular weight of 4000 to intrinsic viscosity polyethylene glycol obtained by polymerizing 3-10 weight% Co the 12000 0.4-0.6 polyethylene terephthalate-based copolymer of polymerization polyester is preferred. Here, 5-sodium sulfoisophthalic acid contributes to the melt viscosity increased and hydrophilic polyethylene glycol (PEG) improves the hydrophilicity. Further, PEG as the molecular weight is large, there is a hydrophilic increasing effect thought to be due to its higher-order structure, since the reactivity becomes worse blend system, problems arise in terms of heat resistance and spinning stability I fear there is. Further, when the copolymerization amount is more than 10 wt%, the melt viscosity may deteriorate.
[0027]
　On the other hand, the hardly soluble polymer forming the island component, polyamides, polyesters, polyolefins, polyphenylene sulfide (PPS) and the like as a preferable example. Specifically, in applications that require mechanical strength and heat resistance, the polyesters, polyethylene terephthalate (hereinafter also referred to as "PET".), Polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, these are the main repeating unit, isophthalic acid and 5-sulfoisophthalic acid metal salt aromatic dicarboxylic acids and adipic acid such as, hydroxycarboxylic acid condensate such as aliphatic dicarboxylic acids and ε- caprolactone sebacic acid, diethylene glycol Ya trimethylene glycol, tetramethylene glycol, copolymers of glycol component such as hexamethylene glycol, and the like are preferable. Also, the polyamides, nylon 6, aliphatic polyamides such as nylon 66 are preferable. On the other hand, polyolefins and can hardly attacked by acid or alkali or the like, there are features such as use as a relatively low binder component after removal as ultrafine fibers to the melting point, high density polyethylene, medium density polyethylene, high-pressure process low density polyethylene, linear low density polyethylene, isotactic polypropylene, ethylene-propylene copolymers, may be mentioned as preferred examples of ethylene copolymers of vinyl monomers such as maleic anhydride. Especially polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate isophthalate copolymer of not more than 20 mole% terephthalate isophthalate, polyethylene naphthalate, polyesters etc., or nylon 6, aliphatic polyamides such as nylon 66 s is is provided with the heat resistance and mechanical properties due to high melting point, compared to the ultrafine fibrillated fibers of polyvinyl alcohol / polyacrylonitrile mixed spun fibers, preferably applicable to applications that require heat resistance and strength. Incidentally, the island component is not limited to a round cross-section, it may be a modified cross-section such as triangular cross-section and flat cross section.
[0028]
　The polymer forming the polymer and island component to form the sea component, to the extent that does not affect the physical properties of microfine fibers after spinnability and extraction, if necessary, organic fillers, antioxidants, heat stabilizers agents, light stabilizers, flame retardants, lubricants, antistatic agents, rust inhibitors, crosslinking agents, foaming agents, fluorescent agents, surface smoothing agents, surface gloss modifiers, release modifiers such as fluororesin, various additives and the like It may safely be contained agent.
[0029]
　In the sea-island type composite fiber of the, it preferably has a melt viscosity of the sea component is larger than the melt viscosity of the island component polymer at the time of melt spinning. According to some cases in relation also combined weight ratio of the sea component becomes less and less than 40%, it is easy to prevent the bonding of the island together.
[0030]
　Preferred melt viscosity ratio (sea / island) is in the range of 1.1-2.0, especially 1.3-1.5. It is likely to bonding island component upon melt spinning when this ratio is less than 1.1, whereas when exceeding 2.0 may deteriorate the spinning tension since the viscosity difference is too large.
[0031]
　Then the number of islands is preferably 100 or more (more preferably 500-2000) is. Moreover, the sea-island composite weight ratio (sea: island) is 20: 80-80: preferably the range of 20. With such a range, it is possible to reduce the thickness of the sea component between the islands, it is easy to dissolve and remove the sea component, the conversion to microfine fibers of the island component is facilitated preferred. Here too thick thickness of the sea component in the case where the ratio of the sea component exceeds 80%, while in the case of less than 20% is too small an amount of the sea component, joined to the islands is likely to occur.
[0032]
　The spinneret used for melt spinning, it is possible to use an arbitrary one such as those having a hollow pin group and micropores group for forming the island component (pinless). For example, join a sea component flow that is designed to flow channel in the form of filling the hollow pin and micropores from extruded island component and between them, in a spinneret such sea-island cross-section is formed by compressing this good. The discharged sea-island type composite fiber is solidified by cooling air, the undrawn yarn taken off by rotating rollers or ejector is set to a predetermined take-off speed (that birefringence Δn is 0.05 or less preferred.) Obtaining . This drawing speed is not particularly limited, is preferably 200 ~ 5000 m / min. It is less than 200 meters / min there is a fear that productivity is lowered. Further, there is a possibility that the spinning stability exceeds 5000 m / min is reduced.
[0033]
　The resulting undrawn yarn was may be subjected as it is cutting process or a subsequent extraction process as required (alkali reduction processing), after the drawn yarn through a stretching step and heat treatment step, cutting step or subsequent extraction step may be subjected to (alkali reduction processing). At that time, to the stretching step may be another extension method which performs spinning and drawing in a separate step, it may be used a straight extension method performed immediately after stretching spun in one step. The order of cutting process and the extraction process may be reversed.
[0034]
　Such cutting, it is preferable to cut the undrawn yarn or stretch yarn as it is or the like in a guillotine cutter or a rotary cutter in the tow by bundling a ten to 900 million units units.
[0035]
　When the ultrafine fibers is subjected to alkali reduction processing to the sea-island type composite fibers, the ratio of the fiber and the alkali liquid (bath ratio) is preferably 0.1 to 5%, more from 0.4 to 3% it is preferable that. Although large contact the fiber and an alkali solution is less than 0.1%, there is a possibility that the process of the waste water is difficult. On the other hand, too many fibers amount exceeds 5%, there is a possibility that entanglement occurs between fibers during alkali reduction processing. It should be noted that the bath ratio is defined by the following equation.
Bath ratio (%) = (fiber mass (gr) / aqueous alkaline solution weight (gr)) × 100
　Further, it is preferable that the processing time of the alkali reduction processing is from 5 to 60 minutes, further 10 to 30 minutes It is preferred. In less than 5 minutes may become insufficient alkali reduction. On the other hand, there is a risk that also reduced to the island component exceeds 60 minutes.
[0036]
　Further, in the alkali reduction processing, it is preferred that the alkali concentration is from 2.0 to 10.0%. If it is less than 2.0%, it becomes alkali insufficient, there is a possibility that loss speed is very slow. On the other hand, caustic exceeds 10.0% proceeds too, there is a risk to be reduced to the island portion.
[0037]
　The method of caustic, a sea-island type composite fibers were placed in an alkali solution, a predetermined condition, from the time, through a dehydration step after caustic treatment in time, again, it was put into water, acetic acid, such as oxalic acid neutralized using organic acids, a method to finally dehydrated promoting dilution, or after processing a predetermined time caustic, then dehydrated promote subjected to neutralization treatment before, and further injecting water dilution a method in which the like. In the former, for processing in batch, but it can perform the production in small amounts (processing), a little low productivity because it takes time for the neutralization process. The latter is susceptible to a semi-continuous production, there is a problem that requires a lot of water for many acid-based solution and diluted at the time of neutralization. The processing facilities not in any way be limited, from the viewpoint of preventing the fibers falling off during dehydration, the aperture ratio as disclosed in Japanese Patent No. 3,678,511 (area ratio of the opening portion per unit area) of 10 to it is preferred to use a mesh-like material is 50% (e.g. non-alkaline-hydrolyzable bag). Very poor omission of moisture in the opening ratio is less than 10%, exceeds 50%, there is a possibility that the separation of the fibers occurs.
[0038]
　Furthermore, after the alkali reduction processing, a dispersing agent in order to enhance the dispersibility of the fibers (e.g., Takamatsu Oil & Fat Co., Ltd. Model YM-81) to the fiber surface, from 0.1 to 5 relative to the fiber weight. 0 it is preferable to weight percent adhesion.
[0039]
　In the bag filter for filter cloth of the present invention, the nonwoven fabric wherein may ultrafine fibers only consist of, but said comprises ultrafine fibers 3 to 50 wt%, and fibers with a fiber diameter is greater than the ultrafine fibers 50 ~ it is preferably contained 97 wt%. When the content of the ultrafine fibers is less than 3 wt%, the collection performance may decrease. Conversely, when the content of the ultrafine fibers is greater than 50 wt%, the pressure loss may increase. Further, the nonwoven fabric may have a multilayer structure, each layer, the ultrafine fibers preferably contain a layer weight versus 3-50% by weight.
[0040]
　Said ultrafine fibers the nonwoven fabric, if the fiber diameter constitute de greater fibers than the microfine fibers (other fibers), other fibers, single fiber fineness of 0.05 ~ 2.2 dtex (more preferably 0.1 ~ 0.9dtex) fibers are preferred. Single fiber fineness of other fibers is small and the pressure loss may be larger than 0.05Dtex. When the single fiber fineness of other fibers conversely is larger than 2.2 dtex, or a lack of strength becomes insufficient entanglement between fibers by high-pressure water in making the spun lace nonwoven fabric, a non-uniformity of pore size resulting brushing with the result powder cause of clogging (dust) and is likely to be reduced.
[0041]
　As the type of such other fibers, polyester fibers, polyphenylene sulfide (PPS) fibers, polyamide fibers, polyolefin fibers, such as rayon are preferable.
[0042]
　In the nonwoven fabric having a basis weight ~ 90 g 10 / m 2 (more preferably 20 ~ 50 g / m 2 is preferably) in the range of. Said purpose with the 10 g / m 2 when less than the variation of the pore size is increased, resistance dropped collecting performance and payment may be deteriorated. Conversely, said purpose with the 90 g / m 2 there is a possibility that a large pressure loss than increases.
[0043]
　Further, in the nonwoven fabric preferably has a thickness in the range of 0.2 ~ 0.6 mm. It said thickness may be reduced small and the collection performance than 0.2 mm. Conversely, (sometimes referred to as "pressure loss".) And said thickness is greater than 0.6mm pressure loss which may increase.
[0044]
　Further, in the nonwoven fabric, it is preferable that the porosity is in the range of 90 to 97%. Void ratio is liable to increase is small and pressure loss than 90%. Conversely, if the porosity is greater than 97%, there is a possibility that dust in the gap is not even eliminated by entering backwashing.
[0045]
　Manufacturing method of the nonwoven fabric is not particularly limited as long as it is a method for entangling the fibers by high pressure water jet. Among them, after Papermaking forming a wet paper by using the ultrafine fiber in enhancing the dispersibility of the ultrafine fibers, a method of entangling fibers by high pressure water jet is preferred.
[0046]
　Type of the nonwoven fabric is not particularly limited, but is preferably a spun lace nonwoven fabric. At that time, it may be obtained spunlaced nonwoven fabric having a multilayer structure by then sequentially introduced providing a plurality of papermaking slurry. For example, to obtain a paper making slurry for the first layer, than papermaking slurry for the first layer was prepared a paper making slurry for the second layer low content of ultrafine fibers, a spun lace nonwoven fabric having a multilayer structure by sequentially turned Te more layers of content of ultrafine fibers suppresses the HSS when dust enters the dust inlet side, it is possible to improve the collection performance while suppressing the pressure loss preferred.
[0047]
　In the bag filter for filter cloth of the present invention, as shown in FIG. 1, the nonwoven fabric is laminated to the base fabric.
[0048]
　At that time, a needle punched nonwoven preferably comprises a scrim as a base fabric. Against wind pressure of the dust flow and backwash pulses by scrim, it is possible to reduce the dimensional change.
[0049]
　The basis weight of such scrim 40 ~ 120 g / m 2 is preferably in the range of. Said purpose with the 40 g / m 2 when less than, which may cause the blow leakage plastically deformed against wind pressure. Conversely said purpose with the 120 g / m 2 or a resistance to needle in large and needlepunching process than the scrim itself may become a cause of increase in pressure loss.
[0050]
　Such scrim, for example, a flat tissue fabric composed of long fibers or short fibers of a single fiber fineness 1.0 ~ 3.0dtex (5 ~ 20 fastest ply yarn preferably fiber length 20 ~ 80 mm) is preferred. Fibers type, polyester fiber, polyphenylene sulfide (PPS) fiber, meta-type, or para-aromatic polyamide fibers are preferred.
[0051]
　Further, the needle polyester fiber as a fiber constituting the non-scrim in punched nonwoven fabric, polyphenylene sulfide fibers, meta-type wholly aromatic polyamide fibers, such as para-type wholly aromatic polyamide fibers are preferred.
[0052]
　In the bag filter for filter cloth of the present invention, the spunbond nonwoven fabric is preferred as the base fabric. The basis weight of such spun bonded nonwoven fabric 100 ~ 400 g / m 2 is preferably in the range of. Said purpose with the 100 g / m 2 there is a possibility that deformation occurs due to wind pressure by insufficient rigidity when forming smaller and pleats than. Conversely said purpose with the 400 g / m 2 greater than that there is a possibility that pressure loss becomes large. Preferably polyester fibers or polyphenylenesulfide fibers as the fibers constituting such spunbonded nonwoven fabric.
[0053]
　In the bag filter for filter cloth of the present invention, as a method of laminating a nonwoven fabric substrate can be a known method. For example, thermal bonding method, a chemical bonding method using an adhesive may be any such sewing.
[0054]
　In the bag filter for filter cloth of the present invention, the nonwoven fabric such as is because it is laminated to the base fabric, excellent collection performance, is excellent in resistance flicked hardly clogged with low pressure loss.
[0055]
　Next, the bag filter of the present invention comprises using the above filter cloth for bag filter, wherein the nonwoven fabric is a bag filter comprising disposed on the dust inlet side. Ingress of dust by the nonwoven fabric which is disposed on the dust inlet side is suppressed, excellent collection performance, is excellent in resistance flicked hardly clogged with low pressure loss.
[0056]
　In such bag filters, it can be suitably used such as the dust collector a bag-shaped bag filter or a bag filter of the cartridge type is subjected to sewing (for example, a bag-like sewing) or pleating.
Example
[0057]
　It explained in detail below Examples and Comparative Examples of the present invention, but the present invention is not limited thereto. Each measurement items in Examples were measured by the following method.
(1) Fiber diameter D
　using a transmission electron microscope TEM (with length measurement function), and taking the fiber cross-section photograph magnification of 30,000 was measured fiber diameter D (nm). However, the fiber diameter D is (mean value of n number 5) with the diameter of the circumscribed circle of the single fiber cross-section.
(2) Fiber length L
　by a scanning electron microscope (SEM), the ultra-fine short fiber before the sea component is dissolved and removed (short fiber A) and a state laid on a substrate, the fiber length L of 20 to 500 times the (mm) was measured (average value of n number 5). At that time, it was measured fiber length L by utilizing the length measurement function of the SEM.
(3) basis weight
　basis weight (g / m based on JIS P8124 (meters basis weight measurement method of paper) 2 was measured).
(4) Thickness
　The thickness (mm) of was measured according to JIS P8118 (method of measuring the thickness and density of paper and paperboard). Measuring load is 75 g / cm 2 at, measured at n = 5, the average value was obtained.
(5) porosity
　the basis weight and thickness, the density of the polyethylene terephthalate (PET) fibers 1.36 g / cm 3 as was calculated from the following equation.
Porosity (%) = 100 - (((basis weight) / (thickness) /1.36) ×
100) (6) PF value
　of the following formula from the pressure loss and the collection rate, performance index of the filter calculated.
PF value = -log (0.3 micron transmittance (%) / 100) / (pressure loss (Pa) /9.8) × 100
(7) Dust retention
　amount: DHC concentration JIS8 or dust 1 g / m 2 , the inflow was introduced into the filter at a rate 10 cm / sec, the pressure loss is measured dust weight are retained by the filter at that time and the time to reach 2 kPa, 1 m 2 in terms of dust holding amount per.
(8) Melt viscosity
　after the polymer after drying treatment was set to an orifice set at ruder temperature of 5 minutes melt holding time of spinning, extrusion under a load of several levels, plotted shear rate and melt viscosity at that time to. The data on the basis of the shear rate - to create a melt viscosity curve, the shear rate has read a melt viscosity at the time of of 1,000 sec-1.
(9) alkali reduction rate ratio
　of the polymer of the sea component and the island components, respectively, discharge diameter 0.3 mm, a circular hole of length 0.6mm from a nozzle having 24 holes, taken off at 1000 ~ 2000 m / min spinning speed created a multi-filament of 83 dtex / 24 filaments by drawing an undrawn yarn was obtained as residual elongation is in the range 30-60%. With 1.5 wt% NAOH solution 80 ° C. This, as a bath ratio of 100, was calculated reduction rate from the dissolution amount and dissolution time.
(10) Air Permeability
　accordance JIS L1096-1990, the test piece through 15cm × weft 15cm were collected 3 points per 1m width of the sample, the amount of air passing through a test piece by Frazier method (cc / cm 2 · sec) It was measured, and the average value was calculated.
(11) bag filter performance test
　filtration performance was according to JIS Z8901-1. The following measurement conditions measurement results from clogging the difficulty by, was to determine the brushing property.

filtration speed: 2.0 m / min
cutting filter cloth size: 500 mm × 500 mm
effective filtering area (suction surface): 0.09 m 2 (300 mm × 300 mm)
Dust concentration: 5.0 g / m 3
and払落air pressure: 500kPa
払落and time: 50ms
払落and conditions initial performance: △ drop If you pay reached P = 1000Pa. 30 times
　　　　　brushed off at five-second intervals: aging. 5000 times
　　　　　stabilization process: △ drop If you pay reached P = 1000Pa. 10 times
　　　　　stabilized after performance: △ P = 30 times dropping Once payment reached 1000Pa
use powder: JIS 10 kinds fly ash average particle diameter: 3.77Myuemu
　　　　　particle size 10μm or less: 96.6%
Performance Measurement: Pressure loss (Pa) and exhaust concentration (mg / m 3 )
　　[example 1]
　island melt viscosity at components 285 ° C. is 120 Pa · sec polyethylene terephthalate, polyethylene with an average molecular weight of 4000 melt viscosity of 135Pa · sec at 285 ° C. in a sea component glycol 4 wt%, the 5-sodium sulfoisophthalic acid using 9 mol% copolymerized modified polyethylene terephthalate, sea: island = 10: spun using a 90 die island number 400 in a weight ratio of the spinning speed It was taken off at 1500m / minute. Alkali reduction rate difference was 1000 times. After stretching it to 3.9 times, and cut to 1000μm in guillotine cutter, to obtain a microfine fiber A Yogai island type composite fibers. This was reduced by 10% at 75 ° C. in 4% NaOH aqueous solution, the present fiber was a microfine fiber A (fiber diameter 700 nm, fiber length 1 mm, aspect ratio 1400, a round cross-section).
[0058]
　Then, the A20 wt% ultrafine fibers, basis weight 10 g / m made of 80 wt% polyethylene terephthalate staple fibers of single fiber fineness 0.1 dtex × fiber length 5 mm 2 and the first layer of a single fiber fineness 0.1 dtex × fiber length 5mm polyethylene terephthalate short fibers 50% by weight and the single fiber fineness 0.8 dtex × fiber length 7mm basis weight 20 g / m rayon 50% by weight of 2 total basis weight 30 g / m and a second layer of 2 to obtain a spun lace nonwoven fabric It was.
[0059]
　At that time, the paper making slurry comprising components of the first and second layers respectively individually adjustable, is introduced into the headbox of a paper machine, to adjust the slurry supply amount and the white water supply amount so that a predetermined basis weight, laminated after forming the wet paper web was performed entangling process at a high pressure jet water pressure 100 kPa.
[0060]
　Then, the aim of voids increase, at a hot air temperature of 145 ~ 155 ° C., it was carried out air-through heat treatment processing.
[0061]
　On the other hand, single fiber fineness 2.2 dtex × fiber length 51 mm, through a short fiber made of a polyester fiber crimped number 11.5 Ke /2.54cm the card and web of cross wrap laminate. Then, the laminated web 2 rolls prepared, basis weight 80 g / m on the intermediate 2 across the scrim, basis weight 520 g / m 2 to obtain a needle-punched nonwoven. Here, scrim, composed 10th ply yarn consisting of polyester staple fibers (single fiber fineness 2.2 dtex × fiber length 51 mm), weaving density is flat tissue fabric 12 /2.54cm both circumstances.
[0062]
　The resulting spunlaced nonwoven fabric and needle punched nonwoven fabric, the spinning spray method an adhesive resin, bonded laminate, at further 0.99 ° C., subjected to calender heat treatment, the surface was smooth. The evaluation results are shown in Table 1.
[0063]
　　[Example 2]
　In Example 1, the ultrafine fibers A20 wt% and a single fiber fineness 0.1dtex polyethylene terephthalate × fiber length 5mm short fibers 80 wt% of the fiber diameter 700 nm × fiber length 1 mm (aspect ratio = 1400) consisting basis weight 30 g / m 2 except that to obtain a single layer of spunlace nonwoven fabric in the same manner as in example 1. The evaluation results are shown in Table 1.
[0064]
　　[Example 3]
　Island melt viscosity at 285 ° C. to components of 120 Pa · sec polyethylene terephthalate, 4 wt% melt viscosity of polyethylene glycol having an average molecular weight of 4000 is 135Pa · sec at 285 ° C. in the sea component, 5- sodium sulfoisophthalic acid using 9 mol% copolymerized modified polyethylene terephthalate, sea: island = 10: spun using a 90 die island number 400 in a weight ratio of was taken off at a spinning rate of 1500 m / min. Alkali reduction rate difference was 1000 times. Without stretching it, and cut to 1000μm in guillotine cutter, to obtain a microfine fibers B Yogai island type composite fibers. This was reduced by 10% at 75 ° C. in 4% NaOH aqueous solution, the present fiber was microfine fibers B (a fiber diameter 1.2 [mu] m, fiber length 1 mm, aspect ratio 850, a round cross-section).
[0065]
　Then, the B30 wt% ultrafine fibers, basis weight 10 g / m made of 70 wt% polyethylene terephthalate staple fibers of single fiber fineness 0.1 dtex × fiber length 5 mm 2 and the first layer of a single fiber fineness 0.1 dtex × fiber length 5mm polyethylene terephthalate short fibers 50% by weight and the single fiber fineness 1.2 dtex × fiber length 5mm polyethylene terephthalate short fibers 50 basis weight 20 g / m consisting wt% of 2 total basis weight 30 g / m composed of the second layer of 2 except that to obtain a spun lace nonwoven fabric in the same manner as in example 1. The evaluation results are shown in Table 1.
[0066]
　　[Example 4]
　The same as the ultrafine fiber A15 wt% as in Example 1, the same as the ultrafine fiber B15 wt% as in Example 3, single fiber fineness 0.1 dtex × fiber length 5mm polyethylene terephthalate basis weight consisting of short fibers 70% by weight of 10 g / m 2 and the first layer of a single fiber fineness 0.1 dtex × fiber length 5mm polyethylene terephthalate short fibers 50 wt% and a basis weight 20 g / m made of rayon 50% by weight of single fiber fineness 0.8 dtex × fiber length 7mm of 2 total basis weight 30 g / m composed of the second layer 2 to obtain a spun lace nonwoven fabric, other is as in example 1. The evaluation results are shown in Table 1.
[0067]
　　Example 5
　The same as ultrafine fibers A30 wt% as in Example 1, basis weight 10 g / m made of 70 wt% polyethylene terephthalate staple fibers of single fiber fineness 0.1 dtex × fiber length 5 mm 2 and the first layer of Example 1 the same ultrafine fiber A10 wt%, polyethylene terephthalate monofilament fineness 0.1 dtex × fiber length 5mm short fibers 40% by weight, basis weight 20 g / m rayon 50% by weight of single fiber fineness 0.8 dtex × fiber length 7 mm 2 the second layer total basis weight 30 g / m composed of a of 2 to obtain a spun lace nonwoven fabric, other is as in example 1. The evaluation results are shown in Table 1.
[0068]
　　[Example 6]
　In Example 1, a spunbond nonwoven fabric made Porisuteru fibers of single fiber fineness 1.7 dtex (basis weight 250 g / m as the substrate 2 is bonded laminated), further performing the calender treatment 0.99 ° C. with clearance 2mm and, except for the surface smoothing it was the same as in example 1. The evaluation results are shown in Table 1.
[0069]
　　[Comparative Example 1]
　In Example 1, single fiber fineness 0.1 dtex × basis weight 10 g / m made of polyethylene terephthalate staple fibers 100 wt% of the fiber length 5 mm 2 in the same manner except that the first layer of Example 1 did. The evaluation results are shown in Table 1. From DHC measurement result, long time to reach 2000 Pa, actually dust it can be seen that entering the interior of the spun lace nonwoven fabric and Nipan nonwoven.
[0070]
　　[Example 7]
　In Example 1, the ultrafine fiber A60 wt% and single fiber fineness 0.1 dtex × basis weight 10 g / m made of polyethylene terephthalate staple fibers 40 wt% of the fiber length 5 mm 2 , except that the first layer of It was the same as in example 1. The evaluation results are shown in Table 1. Initial pressure loss is increased.
[0071]
　　[Comparative Example 2]
　Except that no use spunlace nonwoven fabric in the same manner as in Example 1. The evaluation results are shown in Table 1. The initial pressure loss is low, many dust penetration into the nonwoven fabric, because it is difficult dust brushing properties, in long-term operation, the pressure loss is increased, the life is decreased.
[0072]
　　[Comparative Example 3]
　except for using the PTFE film in place of the spun lace nonwoven fabric in the same manner as in Example 1. The evaluation results are shown in Table 1. A a high collection rate, but the pressure loss is high, was poor in energy saving.
[0073]
　　Example 8
　using Example 1 samples was measured in accordance filtration performance JIS Z8901-1. Less initial blow leakage, also small increase in pressure loss, since the residual dust after stabilization treatment is small, to form a dust cake layer in operation early, it by backwashing pulse, release and easily reproduced, excellent energy saving properties, was long-lived.
[0074]
　　[Comparative Examples 4 and 5]
　Comparative Example 4 using the sample of Comparative Example 2, Comparative Example 5 was measured in accordance filtration performance using a sample of Comparative Example 3 in JIS Z8901-1.
[0075]
　　Example 9
　island component 295 melt viscosity at ° C. is 130 Pa · sec polyphenylene sulfide, melt viscosity at 295 ° C. in the sea component of polyethylene glycol having an average molecular weight of 4000 is 145 Pa · sec 4 wt%, 5 sodium sulfoisophthalic acid using 9 mol% copolymerized modified polyethylene terephthalate, sea: island = 30: in a weight ratio of 70 using a die of the island number 400 spun and taken off at a spinning rate of 1500 m / min. Alkali reduction rate difference was 1000 times or more. After stretching it to 3.5 times, and cut to 1000μm in guillotine cutter, to obtain ultrafine fibers C Yogai island type composite fibers. This was reduced by 10% at 75 ° C. in 4% NaOH aqueous solution, the present fiber was a ultrafine fiber C (fiber diameter 700 nm, fiber length 1 mm, aspect ratio 1400, a round cross-section).
[0076]
　Then, C30 wt% ultrafine fibers and a basis weight 10 g / m made of polyphenylene sulfide short fibers 70 wt% of the single fiber fineness 0.9 dtex × fiber length 5 mm 2 and the first layer of a single fiber fineness 0.9 dtex × fiber length 5mm polyphenylene sulfide short fibers 50% by weight and the single fiber fineness 0.8 dtex × fiber length 7mm basis weight 20 g / m rayon 50% by weight of 2 total basis weight 30 g / m and a second layer of 2 to obtain a spun lace nonwoven fabric It was. At that time, the paper making slurry comprising components of the first and second layers respectively individually adjustable, is introduced into the headbox of a paper machine, to adjust the slurry supply amount and the white water supply amount so that a predetermined basis weight, laminated after forming the wet paper web was performed entangling process at a high pressure jet water pressure 100 kPa. Then, the aim of voids increase, at a hot air temperature of 145 ~ 155 ° C., it was carried out air-through heat treatment processing.
[0077]
　On the other hand, single fiber fineness 2.2 dtex × fiber length 51 mm, through a short fiber made of a polyester fiber crimped number 11.5 Ke /2.54cm the card and web of cross wrap laminate. Then, the laminated web 2 rolls prepared, basis weight 80 g / m on the intermediate 2 across the scrim, basis weight 520 g / m 2 to give a needle-punched nonwoven. Scrim is constituted by a 10th ply yarn consisting of polyester staple fibers (single fiber fineness 2.2 dtex × fiber length 51 mm), weaving density is flat tissue fabric 12 /2.54cm both circumstances.
[0078]
　The resulting spunlaced nonwoven fabric and needle punched nonwoven fabric, by a method of spinning spraying an adhesive resin, bonded laminate, at further 180 ° C., subjected to calender heat treatment, the surface was smooth. The evaluation results are shown in Table 2.
[0079]
　　Example 10
　island component 295 melt viscosity at ° C. is 130 Pa · sec polyphenylene sulfide, melt viscosity at 295 ° C. in the sea component of polyethylene glycol having an average molecular weight of 4000 is 145 Pa · sec 4 wt%, 5 sodium sulfoisophthalic acid using 9 mol% copolymerized modified polyethylene terephthalate, sea: island = 30: in a weight ratio of 70 using a die of the island number 800 spun and taken off at a spinning rate of 1500 m / min. Alkali reduction rate difference was 1000 times or more. After stretching it to 3.1 times, and cut to 1000μm in guillotine cutter, to obtain a microfine fiber D Yogai island type composite fibers. This was reduced by 10% at 75 ° C. in 4% NaOH aqueous solution, the present fiber was a microfine fiber D (fiber diameter 400 nm, fiber length 1 mm, aspect ratio 1400, a round cross-section).
[0080]
　Fiber diameter 400 nm × fiber length 1mm and microfine fibers D40% by weight of (aspect ratio = 1400), single fiber fineness 0.9 dtex × fiber length 5mm polyphenylene sulfide short fibers 60 wt% basis weight 30 g / m consists of 2 monolayers of except that to obtain a spun lace nonwoven fabric in the same manner as in example 9. The evaluation results are shown in Table 2.
[0081]
　　[Examples 11 and 12]
　Example 11, using the samples of Example 9, Example 12 filtration performance using a sample of Example 10 was measured according to JIS Z8901-1.
[0082]
[Table 1]

[0083]
[Table 2]

Industrial Applicability
[0084]
　According to the present invention, excellent collection performance, hardly clogged with low pressure loss, the dust removal excellent filter cloth and a manufacturing method thereof and a bag filter for bag filter to properties is provided, the industrial value is extremely it is large.
DESCRIPTION OF SYMBOLS
[0085]
A non-woven
ground fabric

claims
[Claim 1]
　A filter cloth for bag filter comprising a nonwoven fabric and the base fabric,
　the nonwoven fabric, filter cloth for bag filter, wherein the fiber diameter D includes ultrafine fibers of 200 ~ 2000 nm.
[Claim 2]
　In the above ultrafine fiber is in the range of the ratio L / D of 200 to 4000 fiber length L to the fiber diameter D, the filter cloth for bag filter of claim 1.
[Claim 3]
　The ultrafine fiber is a polyester fiber or polyphenylene sulfide fiber, filter cloth for bag filter of claim 1 or claim 2.
[Claim 4]
　In the polyester fiber, elongation is 60% or less than 60%, the filter cloth for bag filter of claim 3.
[Claim 5]
　The nonwoven fabric wherein the ultrafine fibers are contained 3-50 wt%, a bag filter for filter cloth according to any one of claims 1-4.
[Claim 6]
　The nonwoven fabric is a spun lace nonwoven fabric, filter cloth for bag filter according to any one of claims 1 to 5.
[Claim 7]
　The nonwoven fabric has a multilayer structure, the filter cloth for bag filter according to any one of claims 1 to 6.
[8.]
　The basis weight of 10 ~ 90 g / m in the nonwoven fabric 2 is in the range of, bag filter for filter cloth according to any one of claims 1 to 7.
[Claim 9]
　Wherein is in the range of 0.2 ~ 0.6 mm thick in the nonwoven fabric, a bag filter for filter cloth according to any one of claims 1-8.
[Claim 10]
　The porosity is in the range of 90-97% in the spun lace nonwoven fabric, filter cloth for bag filter according to any one of claims 6-9.
[Claim 11]
　The base fabric is, basis weight 40 ~ 120 g / m 2 comprising a scrim, a needle punched nonwoven fabric, a bag filter for filter cloth according to any one of claims 1 to 10.
[Claim 12]
　The base fabric is, basis weight 100 ~ 400 g / m 2 spunbond nonwoven fabric, a bag filter for filter cloth according to any one of claims 1 to 10.
[Claim 13]
　After the fiber diameter D to obtain ultrafine fibers of 200 ~ 2000 nm by dissolving and removing the sea component of the formed sea-island type composite fiber with a sea component and island component to obtain a nonwoven fabric using ultrafine fibers, the laminating nonwoven fabric substrate, a manufacturing method of a bag filter for filter cloth according to claim 1.
[Claim 14]
　Using the bag filter for filter cloth according to any one of claims 1 to 12, bag filter wherein the nonwoven fabric is arranged on the dust inlet side.
[Claim 15]
　It becomes subjected to sewing or pleated, bag filter of claim 14.