JP2011000580A - Air filter medium and apparatus for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inexpensively manufacture a filter having a high performance and a stable quality by perfectly exhibiting a superfine fiber effect when manufacturing the filter by folding an air filter medium prepared by laminating and fixing a superfine fiber sheet having a fiber size of 1 μm or less onto a filter base material constituted with synthetic fiber or glass fiber so as not to be separated.SOLUTION: An apparatus for manufacturing the air filter medium comprises: an electrospinning forming part; a base material supply part; a fusion-bonding member supply part; a cover material supply part; a heating and drying part; a winding part; and a volatile solvent removing device, whereby the air filter medium is manufactured and, in particular, the air filter medium composed of the combination of four materials of the filter base material, the superfine fiber sheet, a fusion-bonding member and a cover material is inexpensively provided by continuously manufacturing the air filter medium while circulating air between an electrospinning forming device and a volatile solvent removing device and reducing an energy loss.

Description

  The present invention relates to an air filter medium in which an ultrafine fiber sheet manufactured by an electrospinning method is incorporated in a filter base material, and an apparatus for manufacturing the same.

  In general air filters used in clean rooms and general air conditioning in the semiconductor field, biochemical field, etc., various attempts have been made to filter air filters in order to increase the collection efficiency and reduce clogging or extend the service life. Yes.

  Therefore, in recent years, a method for producing ultrafine fibers has been developed, and a sheet made of an assembly of ultrafine fibers has a higher specific surface area than a sheet made of conventional fibers, and has a uniform and small pore diameter. As can be seen, filter media using ultrafine fibers have been developed.

  As one of them, it is considered to incorporate the ultrafine fiber sheet into the filter base material in order to produce a product without damaging the ultrafine fiber sheet. However, it is difficult to continuously incorporate the ultrafine fiber sheet into the filter base material at low cost, and an optimum production method is strongly desired.

  On the other hand, an electrospinning method is employed in order to use ultrafine fibers as a filter medium. In this electrospinning method, a spinning solution in which a polymer material capable of forming ultrafine fibers is dissolved in a volatile solvent is extruded from a nozzle and made into a fiber by applying an electric field to form a superfine fiber sheet on a laminate such as a filter substrate. Is the method. At this time, the volatile solvent is volatilized. However, if the concentration is high, there is a risk of explosion, and if it is scattered to the outside air, the environment is polluted, so that it is released to the outside via a scrubber.

  Here, in the electrospinning method, it is necessary to set the temperature and humidity in the apparatus within a certain range. However, in the above method, the air controlled to the constant temperature and humidity is discarded, so there is a problem of energy cost loss. There was concern.

Problems to be solved by the invention

  Accordingly, the present invention is intended to solve these problems, and a first object of the present invention is to solve the conventional disadvantages that occur when a superfine fiber sheet manufactured by an electrospinning method is incorporated in a filter substrate. It is what.

  The second object of the present invention is to provide a highly efficient air filter medium with a low pressure loss by incorporating a superfine fiber sheet produced by an electrospinning method into a filter substrate.

  The third object of the present invention is to prevent environmental pollution by volatile solvents and to reduce the energy cost for adjusting the temperature and humidity in the apparatus.

  The fourth object of the present invention is to produce a filter medium at low cost.

Means for solving the problem

  The first solving means of the present invention is characterized in that the filter medium is composed of four combinations of a filter base material, an ultrafine fiber sheet, a fused fiber sheet, and a cover material.

  The second solving means of the present invention is that the filter medium production apparatus is an electrospinning generator, a base material supply unit, a fusing member supply unit, a cover material supply unit, a heating / drying unit, a winding unit, and a volatile solvent removal. It is characterized by comprising the apparatus.

  The third solving means of the present invention is characterized in that an adsorbent having a function of adsorbing and removing a volatile solvent is incorporated in the volatile solvent removing apparatus.

  The fourth solution of the present invention is characterized in that an air conditioner is connected to the volatile solvent removing device.

  The fifth solution of the present invention is characterized in that the volatile solvent removing device and the electrospinning generator are connected by a circulating air duct.

Here, the filter substrate is composed of synthetic fibers or glass fibers having a basis weight of 40 to 100 g / m ² .

The cover material is composed of synthetic fibers or glass fibers having a basis weight of 20 to 100 g / m ² .

  Furthermore, the ultra-fine fiber sheet is formed by electrospinning. Specifically, by applying an electric field to the spinning solution supplied from the nozzle, the fiber sheet is drawn, fiberized, and dispersed on the surface of the filter substrate. It is sprayed into an ultrafine fiber sheet.

  This spinning solution is a solution in which a polymer material is dissolved. Examples of the polymer material include polyethylene glycol, polylactic acid, polyglycolic acid, polyacrylonitrile, polystyrene, polyamide, polyethylene, aramid, polyethersulfone, and polypropylene. As the solvent for the spinning solution, for example, a volatile solvent such as acetone, methanol, ethanol, propanol, toluene, benzene, cyclohexane, dimethylacetamide, dimethylformamide or the like is used. However, various polymer materials and volatile solvents are used without being limited to the above examples.

  As the fusion member, a member having an effect of adhesion by heating, such as a fusion fiber sheet, is used. As the fused fiber sheet, a thermal adhesive sheet such as polyamide, polyester, polyolefin, special olefin, polyurethane, or aramid is used. Moreover, the gist of the present invention is not changed at all even if a fusing member such as hot melt powder is used instead of the fusing fiber sheet.

  Next, the electrospinning generator has a box shape, and a nozzle for injecting a spinning solution obtained by dissolving a polymer material with a volatile solvent is disposed therein. A notch is provided facing the upper and lower portions in front of the nozzle, and the filter base material is formed to pass through the gap. The electrospinning generator is provided with an air supply connection port and an exhaust connection port.

  The base material supply unit and the cover material supply unit are obtained by winding the filter base material and the cover material around respective paper tubes.

  In the case of a sheet shape such as a fused fiber sheet, the fusing member supply unit is obtained by winding a sheet around a paper tube. In the case of a fusion member such as hot melt powder, it is uniformly dispersed using a quantitative supply device or the like.

  The winding unit has a function of winding the filter base material, the cover material, and the fusion member.

  The heating / drying section has a box shape and is provided with a heater inside, and an inlet opening and an outlet opening are formed on both sides. Further, the heating / drying section does not change the gist of the present invention even if a heating roll or the like is used.

  The volatile solvent removing apparatus contains an adsorbent having a function of adsorbing and removing the volatile solvent, such as an activated carbon filter and a blower. An air conditioner is connected to the volatile solvent removing device, and a part of air can be exhausted to the outside.

  The effect | action by the said problem-solving means is as follows. That is, when the spinning solution is ejected from the nozzle of the electrospinning generator, the blower and the winding unit of the volatile solvent removing device are driven. The spun solution thus jetted is made into ultrafine fibers and continuously laminated on the filter substrate to form a superfine fiber sheet. Next, the filter base material on which the ultra-fine fiber sheets are laminated overlaps with the fusion member and the cover material and enters the heating / drying section, and the ultra-fine fiber sheet, the filter base material, and the cover material are integrated by heat melting of the fusion member. And is wound around the winding portion as an air filter medium.

  At this time, the air exhausted from the electrospinning generator enters the volatile solvent removal device through the circulating air duct connected to the exhaust connection port, and the volatile solvent by the adsorbent installed in the volatile solvent removal device. Is removed. The air from which the volatile solvent has been removed is mixed with a small amount of air that is sent from the air conditioner and maintained at a constant temperature and humidity, and the temperature and humidity are adjusted from the air supply connection port of the electrospinning generator. Supplied to the electrospinning generator. Since the air from which the volatile solvent has been removed in this way is reused, the energy cost can be reduced. It is also possible to exchange the circulating air by exhausting the same amount of air taken from the air conditioner to the outside.

  The air filter medium is cut into a predetermined size and then folded into a zigzag shape so that the air filter medium is air-tightly attached to a quadrilateral frame by sandwiching an appropriate material separator or bead adhesive between the filter mediums, and used as an air filter. Is done.

  The air filter medium may be a combination of only a filter base and an ultrafine fiber sheet, or a combination of a filter base, an ultrafine fiber sheet and a fusion member, and a combination of a filter base, an ultrafine fiber sheet and a cover material. The gist of the present invention is not changed at all.

The invention's effect

The effects obtained when the air filter medium made according to the present invention is used as an air filter and the effects obtained when the manufacturing apparatus according to the present invention is used are as follows.
(1) Since the ultra-fine fiber sheet manufactured by the electrospinning method is incorporated into the filter medium, it is possible to collect fine particles efficiently and accurately with the ultra-fine fiber sheet. An efficient filter medium can be provided.
(2) Since the life of the filter medium is extended, the replacement cost can be reduced.
(3) Since an extreme increase in pressure loss can be suppressed, energy saving in driving operation such as a fan can be achieved.
(4) Since the filter medium is integrated into a single sheet, when the filter medium is assembled as a medium-high performance filter, quasi-HEPA filter, HEPA filter, ULPA filter, the ultra-fine fiber sheet is cracked or broken, etc. Will not cause any trouble.
(5) Since the circulating air containing the volatile solvent is a system that is reused via the volatile solvent removing device, it is possible to reduce the energy cost for generating the air whose temperature and humidity are adjusted.
(6) The filter medium manufacturing apparatus of the present invention can continuously produce a filter medium in which super fine fibers are laminated, and can reduce energy costs, so that the filter medium can be manufactured at low cost.

Schematic which shows the manufacturing apparatus of the air filter medium of this invention. Schematic which shows the air filter medium of this invention.

  Hereinafter, a filter medium and an apparatus for manufacturing the same according to an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is an overall configuration diagram of a filter medium manufacturing apparatus. Reference numeral 1 denotes a filter base material supply unit, and a sheet-like filter base material 2 is wound around the filter base material supply unit 1 to be rotatably supported. And the filter base material 2 is drawn out from the filter base material supply part 1.

  3 is an electrospinning generator, and a nozzle 4 for injecting a spinning solution in which a polymer material is dissolved in a volatile solvent is disposed. Notches 5 and 6 are provided facing the upper and lower portions in front of the nozzle 4 so that the filter substrate 2 passes through the gap. An air supply connection port 7 is formed at the bottom of the electrospinning generator, and an exhaust connection port 8 is formed at the side.

  Reference numeral 9 denotes a cover material supply unit, in which a cover material 10 is wound in a roll shape and is rotatably supported.

  Reference numeral 11 denotes a fusing member supply unit. In this example, a fusing fiber sheet 12 is wound in a roll shape and is rotatably supported.

  Reference numeral 13 denotes a winding unit having a function of winding the filter base material 2, the cover material 10, and the fused fiber sheet 12.

  Reference numeral 14 denotes a heating / drying unit, which is provided with a heater inside and has a sheet inlet opening and an outlet opening formed on both side surfaces.

  Reference numeral 15 denotes a volatile solvent removing device, and an adsorbent having a function of adsorbing and removing a volatile solvent inside, in this example, an activated carbon filter 16 and a blower 17 are built in. The device 15 includes an air supply duct 18 and a circulating air duct 19. Each end of the conditioned air duct 20 is connected. An air conditioner 21 is attached to the end of the conditioned air duct 20. An exhaust duct 22 is branched and connected from the air supply duct 18.

  The other end of the air supply duct 18 is connected to the air supply connection port 7 of the electrospinning generator 3. The other end of the circulating air duct 19 is connected to the exhaust connection port 8 of the electrospinning generator 3 so that air can circulate between the electrospinning generator and the volatile solvent removing device.

  Reference numeral 23 denotes an air volume adjusting damper attached to the air supply duct 18, the conditioned air duct 20, and the exhaust duct 21.

  Next, a method for producing a filter medium using the filter medium production apparatus will be described.

  First, the blower 17 of the volatile solvent removing device 15 is activated, and air is circulated between the electrospinning generator 3 and the volatile solvent removing device 15. At this time, the air conditioner 21 is also activated, introduced into the volatile solvent removing device 15 through the conditioned air duct 20, and the temperature and humidity conditions of the circulating air are set so as to satisfy the temperature and humidity conditions in the apparatus required for the electrospinning method. adjust.

  Next, injection of the spinning solution is started from the nozzle 4 of the electrospinning generator 3, and the winding unit 13 is driven. As a result, the filter substrate 2 passes through the notch 5 of the electrospinning generator 3 and the injected spinning solution is made into ultrafine fibers and continuously laminated on the filter substrate 2 to form the ultrafine fiber sheet 24. Formed as.

  Next, the filter base material 2 on which the superfine fiber sheets are laminated is superposed on the fusion fiber sheet 12 and the cover material 10, enters the heating / drying section, and is thermally fused to the filter base material 2, the ultrafine fiber sheet 12. The fiber sheet 24 and the cover material 10 are united together and wound up by the winding unit 13 as the air filter medium 25.

  The air filter medium 25 manufactured by the above manufacturing method is cut into a predetermined width and then folded into a zigzag shape so as to be folded, and a separator or bead adhesive made of an appropriate material is sandwiched between the filter mediums to form a square frame. Airtightly attached, medium-high performance filter, quasi-HEPA filter, HEPA filter, ULPA filter are formed.

  The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage, and a plurality of components disclosed in the embodiment. Various modifications can be made by an appropriate combination of the above.

  In the industry dealing with air conditioning filters, filters with low pressure loss, high collection efficiency and long life have been pursued. However, these performances have contradictory performances, making it difficult to create an ideal one. Therefore, the development of air conditioning filters having ideal performance in the filter industry has been attracting attention in recent years due to the development of ultra-fine fibers and the like due to technological development in the textile industry. However, it is difficult to produce continuously while maintaining the temperature and humidity conditions necessary for producing ultrafine fibers, and the cost is high. Therefore, the present invention is intended to solve these problems, and to provide an air filter medium having a high collection rate and a long life with a low pressure loss, and an apparatus for manufacturing the same, which exhibits its ultra-fine fiber effect. Thus, the present invention has extremely high utility value in the industry.

DESCRIPTION OF SYMBOLS 1 ... Filter base material supply part 2 ... Filter base material 3 ... Electrospinning generator 4 ... Nozzle 5, 6 ... Notch 7 ... Supply connection port 8 ... Exhaust Connection port 9: Cover material supply unit 10 ... Cover material 11 ... Fusion member supply unit 12 ... Fusion fiber sheet 13 ... Winding unit 14 ... Heating / drying unit 15 ..Volatile solvent removal device 16 ... activated carbon filter 17 ... blower 18 ... air supply duct 19 ... circulating air duct 20 ... conditioned air duct 21 ... air conditioning device 22 ... Exhaust duct 23 ... Air volume adjustment damper 24 ... Super fine fiber sheet 25 ... Air filter media

Claims (5)

  An air filter medium characterized by comprising four combinations of a filter base material, a microfiber sheet, a fusion member, and a cover material.   An apparatus for producing an air filter medium comprising an electrospinning generator, a base material supply unit, a fusion member supply unit, a cover material supply unit, a heating / drying unit, a winding unit, and a volatile solvent removing device .   The apparatus for producing an air filter medium according to claim 2, wherein the volatile solvent removing device contains an adsorbent having a function of adsorbing and removing the volatile solvent.   The apparatus for producing an air filter medium according to claim 2, wherein an air conditioner is connected to the volatile solvent removing device.   The apparatus for producing an air filter medium according to claim 2, wherein the volatile solvent removing device and the electrospinning generator are connected by a circulating air duct.

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