JP3977507B2 - Pollutant removal device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is used for removing pollutants contained in an air flow, particularly in a semi-enclosed space having a breathing port for adjusting an internal pressure to an external pressure and facing the breathing port. The present invention relates to a contaminant removing device and a magnetic recording disk device having the same.
[0002]
[Prior art]
Magnetic recording disk devices are very sensitive to chemical contamination. Organic vapor is adsorbed on the very smooth surface of the disk and slider and changes the properties of the lubricant coated on that surface. Other chemical pollutants such as SO ₂ May cause corrosion of disk and head metallurgy, especially magnetoresistive read elements. In the past, in order to prevent the entry of such contaminated gas from the outside, the magnetic recording disk device was made in a completely sealed form. However, now that the top cover is being changed to a stainless steel press-molded plate, the volumetric distortion due to temperature changes is large in the completely sealed type, causing problems such as head crashes and case deformations. Generally, the pressure is adjusted by providing the In order to prevent entry of fine particle particles and contamination gas from the outside, a gas adsorption filter in which a gas adsorbent and a particle filter are integrated is often used for this breathing port.
The gas adsorption filter is required to have a low pressure loss. In the case of high pressure loss, it becomes impossible to pass air that can be sufficiently relaxed with respect to temperature changes when the apparatus is turned ON / OFF and pressure changes in the magnetic recording disk apparatus accompanying high-speed rotation of the spindle motor. If it does so, air will infiltrate from places with weak sealability other than a breathing opening, and will cause infiltration of a pollutant. For this reason, activated carbon sheets such as woven fabrics of activated carbon fibers are widely used for the gas adsorption filters. However, this gives a low pressure drop, but its pollutant adsorption capacity per volume is small.
With the increase in recording capacity of magnetic recording disk devices, the use environment has deteriorated due to the high-speed rotation of media and the spread of movable personal computers. The gas adsorption filter installed in the breathing port has a pollutant adsorption capacity. Higher ones are demanded. Japanese Patent Application Laid-Open No. 7-2111055 introduces a filter with improved adsorption performance. This filter is composed of a gas adsorbing fiber layer formed on a non-breathable plate, and has a function of dispersing an air flow colliding with the gas adsorbing fiber layer along the plate surface. However, in such a filter, since the fiber density per unit volume (activated carbon density) in the gas adsorbing fiber layer is usually as small as 0.26 g / cc, the contaminant adsorbing ability is still not satisfactory.
[0003]
[Problems to be solved by the invention]
It is an object of the present invention to provide a pollutant removing device contained in an air flow that has excellent pollutant removing ability and low pressure loss.
[0004]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.
That is, according to the present invention, a gas adsorbing sheet comprising a porous film of a synthetic resin and having a diffusion layer on the surface thereof is accommodated in the container so that the diffusion layer is located on the container opening side, and the container It has a structure in which the opening is sealed with a lid film having an air inlet at the center, and the pressure loss of the gas adsorption sheet is larger than the pressure loss of the diffusion layer, and further in the gas adsorption sheet An apparatus for removing contaminants contained in an air stream is provided, wherein the density of the adsorbent contained is 0.4 to 1.5 g / cc.
Further, according to the present invention, in the pollutant removing device disposed in a semi-sealed space having a breathing port for adjusting the internal pressure to the external pressure and facing the breathing port, as the pollutant removing device, A pollutant removing device contained in air flowing into a semi-enclosed space is provided, wherein the pollutant removing device is disposed and used with its air inlet facing the breathing port of the semi-enclosed space. Is done.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The contaminant removal apparatus of the present invention includes a gas adsorption sheet having a gas diffusion layer.
The gas adsorbing sheet is a sheet-like material made of a gas adsorbent, and can be obtained by forming the gas adsorbent into a sheet and fixing the sheet with a resin, an adhesive, an adhesive, or the like. In order to make the gas adsorbent into a sheet, among them, a fluororesin, particularly PTFE (polytetrafluoroethylene) can be preferably used in the form of a dispersion (dispersion) or powder. By using the fluororesin in such a form, a gas adsorbing sheet having a high adsorbent density and having the adsorbent bonded firmly can be obtained. In this case, as the gas adsorbent, activated carbon, silica gel, zeolite, various clays, alumina, iron oxide, magnesium perchlorate, ion exchange resin, various metal salts and the like can be used alone or in the form of a mixture. The gas adsorbent can be in any shape such as powder, granule, short fiber and the like. The sheet density is 0.4 g / cc or more, preferably 0.5 to 1.0 g / cc. The density of the adsorbent in the sheet is 0.4 g / cc or more, preferably 0.5 to 1.0 g / cc. The upper limit is usually 1.5 g / cc. If the packing density of the adsorbent in the sheet is too high, the pressure loss of the gas adsorbing sheet becomes too high and the function as a breathing filter is lost. In the case of the present invention, it is preferable to use an activated carbon sheet. In this case, the activated carbon sheet is obtained by joining particulate activated carbon with a resin or an adhesive to form a sheet, or activated carbon short fiber with a resin or an adhesive. And the like which are immobilized in the above are included.
[0006]
The gas adsorption sheet used in the present invention preferably has a relatively large pressure loss, and has a pressure loss of 50 mm water column or more, preferably 100 to 10,000 mm water column when an air flow with a wind speed of 5.3 cm / sec is permeated. Are advantageously used. The thickness of this gas adsorbing sheet is 10 μm to 10 mm, preferably 50 to 1000 μm.
The gas diffusion layer stacked on the front surface (respiratory side surface) of the gas adsorbing sheet is a layer that disperses the air flow hitting the front surface of the gas adsorbing sheet along the gas adsorbing sheet surface, and is made of plastic, metal (stainless steel, aluminum , Copper, etc.), carbon, ceramics, etc., or a net-like body made of yarn, non-woven fabric, woven fabric, or other fiber sheet. The thickness of the fiber or thread in this case is 1 to 1000 μm in diameter, preferably 10 to 100 μm. Moreover, the said fiber sheet can consist of a single layer or multiple layers (2-5 layers) of a net-like body, a non-woven cloth, and a fine cloth. The thickness of the fiber sheet (the thickness of the gas diffusion layer) is 10 μm to 5 mm, preferably 50 to 500 μm. The basis weight (basis weight) is 0.05 g / m. ² ~ 1000g / m ² , Preferably 1 g / m ² ~ 100g / m ² It is.
The gas diffusion layer may be laminated on the surface of the gas adsorbing sheet and partially bonded and fixed with an adhesive, or may be laminated only in an unbonded state. The pressure loss of the gas diffusion layer is 5000 mm or less, preferably 500 mm or less. In the case of the present invention, the pressure loss of the gas adsorption sheet must be larger than the pressure loss of the gas diffusion layer.
When an air flow containing a contaminated gas is applied to the surface of the gas diffusion layer of the gas adsorption sheet on which the gas diffusion layer is laminated from the right angle direction, the air flow is directed to the gas diffusion layer in the surface direction, that is, the gas adsorption sheet surface And part of the gas passes through the gas adsorbing sheet. The contaminated gas contained in the air is adsorbed by the gas adsorbent of the gas adsorbing sheet while the air is dispersed along the gas adsorbing sheet surface and while the air passes through the gas adsorbing sheet. Removed from inside.
When an air flow containing pollutant gas is applied to the gas adsorption sheet surface that does not have the gas diffusion layer, in this case, unlike the case where it is applied to the gas diffusion layer, the gas adsorption sheet surface near the peripheral edge of the gas adsorption sheet The contact rate of the air flow is lowered, and as a result, the pollutant gas removal rate is also lowered.
[0007]
In the contaminant removal apparatus of the present invention, the gas adsorption sheet having the gas diffusion layer described above is placed in a container made of a synthetic resin porous film, the gas diffusion layer is directed to the container opening side, and the gas adsorption sheet side is directed to the container. The opening is accommodated toward the bottom surface, and the opening is sealed (sealed) with a lid sheet having an air inlet at the center.
FIG. 1 shows a schematic diagram of the pollutant removal apparatus of the present invention.
In FIG. 1, 1 is a container made of a synthetic resin porous film, 2 is the peripheral edge of the container opening, 3 is a gas diffusion layer, 4 is a gas adsorption sheet, 5 is a lid film, and 6 is an air inlet. .
The lid film 5 seals (seals) the opening of the container 1 and at the same time acts as an adhesive portion for the inner wall surface of the breathing port periphery in the semi-sealed space. In this case, a portion corresponding to the breathing port of the semi-enclosed space is opened and formed in the air inlet 6.
The material of the lid film 5 is not particularly limited, and can be a synthetic resin film, a metal film, or the like. The lid film 5 and the opening peripheral edge 2 of the container 1 are bonded by a heat fusion method or an adhesive method using an adhesive or a pressure-sensitive adhesive. In addition, an adhesive layer may be formed in advance on the lower surface of the lid film 5. The lid film 5 can preferably be a double-sided adhesive tape.
[0008]
In the porous film of a synthetic resin used as a container molding material in the present invention, the average pore diameter is 0.01 to 50 μm, preferably 0.1 to 10 μm, and the porosity is 20 to 98%, preferably 70. It is -95%, The thickness is 1-5000 micrometers, Preferably it is 5-500 micrometers. The material of the film is not particularly limited and may be various materials such as polyester, polyamide, polyethylene, polypropylene, and fluorine-containing resin. In the present invention, stretched porous polytetrafluoroethylene is particularly preferable. When the porous film is formed into a container shape, it is preferable to form the container into a container shape by a suction molding method. In this case, it is not preferable that the porous film has large average pores. The gas permeability of the porous film used in the present invention is represented by the Gurley number and is 5000 seconds or less, preferably 1 to 100 seconds.
[0009]
In a stretched porous polytetrafluoroethylene film (hereinafter also simply referred to as a stretched porous PTFE film) preferably used as a container molding material in the present invention, the thickness is 1-1000 μm, preferably 3-350 μm. The pore diameter is 0.01 to 10 μm, preferably 0.1 to 1 μm, and the porosity is 20 to 98%, preferably 70 to 95%. The stretched porous PTFE film having such characteristics has sufficient mechanical strength as a container molding material, has a high gas permeation rate, and has a low pressure loss of air when passing through it.
[0010]
The stretched porous PTFE film is produced, for example, by the method described in Japanese Patent Publication No. 51-18991 and Japanese Patent Publication No. 56-17216. That is, a preform is prepared by adding and mixing a liquid lubricant, for example, hydrocarbon oil such as solvent naphtha and white oil, petroleum ether, etc., to fine powder of polytetrafluoroethylene resin having a crystallinity of about 95% or more. . The mixing weight ratio in this case is, for example, the liquid lubricant 20 with respect to the polytetrafluoroethylene 80. Next, this preform is extruded from a die into a film using an extruder. The resulting film is stretched at a high speed of 10% or more per second in an unsintered state of 327 ° C. or less with or without removing the liquid lubricant. Next, the stretched product is heat-treated at 200 to 390 ° C. in a stretched state to prevent shrinkage and obtain a desired polytetrafluoroethylene porous film. The film extruded in the extrusion step can be stretched in one or two directions in the stretching step, and a uniaxially stretched film or a biaxially stretched film can be obtained. The porous film of polytetrafluoroethylene thus obtained is composed of very fine fibrils called fibrils and granular nodules called nodes connecting them, and these fibrils and Very fine pores exist between the nodes in a continuous state, form a so-called continuous porous structure, and have high gas permeability.
[0011]
As the stretched porous PTFE film, it is preferable to use a biaxially stretched porous film produced by a biaxial stretching process rather than a uniaxially stretched process in the stretching process. This is because the biaxially stretched film can increase the porosity of the porous film, and can increase the tensile strength and tear strength.
[0012]
The porous film of a synthetic resin used as a container molding material in the present invention can be used by laminating and adhering a breathable stretchable reinforcing material on one side or both sides thereof. In the case of such a laminate film, even if the porous film is a thin layer, it can be used as a container material having sufficient strength.
The breathable stretchable reinforcing material is not particularly limited as long as it is in the form of a film or a sheet made of a synthetic resin fiber having air permeability, and the use of a fabric such as a woven fabric, a nonwoven fabric, a knitted fabric, or a net is possible. preferable. If a fabric obtained from a thermoplastic resin having a melting point lower than that of the porous PTFE film is used as the fabric, it can also serve as an adhesive by fusing it when forming a laminated film, thereby providing a strong laminate. A film can be obtained. Moreover, since such a fabric has stretchability, it does not particularly hinder the container molding by suction molding.
[0013]
When a stretched porous PTFE film is used as the container molding material, this can be one in which the skeleton constituting the porous structure is coated with an organic polymer having water repellency and oil repellency. It is known that porous PTFE loses its durability when contacted with a substance containing a surfactant, an organic solvent, and an oily component. That is, when the gas adsorption unit of the present invention is used in an atmosphere where such a substance is present, these components penetrate into the porous PTFE film and block the pores, thereby impairing the water repellency and air permeability. It was confirmed that the gas adsorbent accommodated in the interior was wetted to reduce its performance. However, by coating an organic polymer having water repellency and oil repellency on the skeleton constituting the porous structure of stretched porous PTFE, the gas adsorption unit of the present invention is made of a porous material such as a surfactant, an organic solvent, and an oil component. It can be used even in an atmosphere in which a substance that lowers the durability of PTFE is present or in an atmosphere where there is a risk of mixing.
[0014]
An organic polymer having water repellency and oil repellency that can be used for this purpose is described in JP-A-8-110071. For example, fluoroalkyl acrylate, fluoroalkyl methacrylate, AF polymer (trade name of DuPont), Cyto Top (trade name of Asahi Glass Co., Ltd.) and the like are preferably used. Moreover, the tetrafluoroethylene (TEF) copolymer described in Unexamined-Japanese-Patent No. 9-156007 can also be used. For example, a copolymer of tetrafluoroethylene and acrylate, methacrylate, acrylonitrile, alkene, particularly a fluoroacrylate / tetrafluoroethylene copolymer, a fluoroacrylate / hexafluoropropylene / tetrafluoroethylene copolymer, etc. are preferably used. .
Furthermore, the method described in the above publication can also be applied to a method of coating these organic polymers on the skeleton constituting the porous structure of expanded porous PTFE.
[0015]
Lamination of the stretched porous PTFE film and the breathable fabric is performed by stacking the stretched porous PTFE film and the breathable fabric and, for example, partially heat-sealing using a gravure pattern roll or the like to obtain a laminated sheet. To be implemented. It is also possible to perform partial adhesion using an adhesive such as urethane resin. In order not to lower the breathing function, it is necessary to minimize the area where the breathable fabric is fused or bonded to the stretched porous PTFE film.
[0016]
The laminated film may have a two-layer or three-layer structure in which a fabric is laminated on one side or both sides of a stretched porous PTFE film.
[0017]
When the porous film is molded into a container shape, in the present invention, the molding is preferably performed by applying a tensile stress to the porous film by a suction molding method. As a result, a smooth container having no wrinkles on the outer surface of the container can be obtained.
FIG. 2 shows a process chart for manufacturing the contaminant removal apparatus of the present invention.
In FIG. 2, 11 is a mold, 12 is a porous film, 1 is a container, 2 is an opening peripheral edge, 3 is a gas diffusion layer, 4 is a gas adsorption sheet, 5 is a lid film, and 6 is an air inlet. . A shows the space part formed in the metal mold | die. This space A corresponds to the space of the container.
In order to manufacture the apparatus of the present invention, the porous film 12 is placed on the upper surface of the mold 11 (FIG. (A)), and the inside of the space A is inserted through the suction hole formed in the mold at the bottom of the space A. Is sucked with a suction pump (vacuum pump) in the direction of the arrow.
In this case, the porous film 12 is heated to the softening temperature as necessary. By this suction, the porous film 12 is stretched by the tensile stress at the time of suction, and is brought into close contact with the wall surface of the mold facing the space A to be molded into the container 1 (FIG. (B)). In this case, the opening peripheral part (collar part) 2 of the container 1 is formed. The draw ratio of the porous film 12 during the suction molding is about 1.5 to 3 times.
Next, the lid film 5 is placed on the porous film 2 including the opening of the container 1 formed as described above, and is adhered to the film 2 (FIG. (C)). In this case, a gas adsorbing sheet 4 having a gas diffusion layer 3 is joined to the center of the lid film 5 via the gas diffusion layer 3.
FIG. 3 shows an external view of the pollutant removing apparatus thus formed.
[0018]
When the container is formed by suction molding, the porous film 12 is formed into a container shape in a state where tensile stress is applied, so that wrinkles are not generated on the outer surface.
In this case, when a stretched porous PTFE film rich in stretchability (flexibility) is used as the porous film, it is not particularly necessary to hold the film in a heated state at the time of suction, but the container is curved with a large curvature. When it has a part, it is preferably heated to about 400 ° C.
As described above, when an easily stretched one such as a stretched porous PTFE film is used as the porous film, heating is not particularly required. However, a porous film of a normal thermoplastic resin such as a polyethylene film or a polypropylene film may be used. In this case, the film is heated to the softening temperature, and the heated film is formed into a container shape by suction.
[0019]
The lid film 5 is not particularly limited as long as it can seal the container opening, and can be a breathable or non-breathable film. In the case of the present invention, the lid film 5 is preferably a porous film of a synthetic resin as described above, particularly a stretched porous PTFE film. The thickness of the lid film 5 is 10 to 1000 μm, preferably 50 to 300 μm. The lid film 5 can be a laminated film in which a reinforcing material is laminated and adhered.
The adhesion between the lid film 5 and the container opening peripheral edge 2 can be heat fusion, adhesion with an adhesive or a pressure-sensitive adhesive, etc., but adhesion with a pressure-sensitive adhesive is simple. Adhesion with an adhesive is performed by previously forming an adhesive layer on the lower surface of the lid film 5 and pressing the lid film 5 on the upper surface of the peripheral edge 2 of the container opening via the adhesive layer. .
[0020]
The adhesion between the lid film 5 and the gas diffusion layer 3 can be heat fusion, adhesion using an adhesive or a pressure sensitive adhesive, etc., but adhesion with a pressure sensitive adhesive is simple. Adhesion with the pressure-sensitive adhesive is carried out by forming a pressure-sensitive adhesive layer on the lower surface of the lid film 5 in advance and pressing the lid film 5 on the upper surface of the gas diffusion layer 3 via the pressure-sensitive adhesive layer. .
[0021]
The pollutant removal device of the present invention is disposed inside a semi-enclosed space having a breathing port for making the internal pressure coincide with the external pressure and facing the breathing port. In this case, the air inlet 6 of the device of the present invention is opposed to the breathing port of the semi-enclosed space, and the air flowing in from the breathing port flows into the device of the present invention from the air inlet 6.
The device of the present invention can be disposed in the semi-enclosed space by adhering the cover film 5 of the device to the inner wall surface of the breathing port peripheral portion using a double-sided adhesive tape or the like.
The air flowing from the breathing port into the semi-enclosed space in which the apparatus of the present invention is disposed passes through the apparatus of the present invention, so that contaminants contained in the air are efficiently removed.
That is, air that has flowed into the apparatus through the breathing port in the semi-enclosed space and the air inlet 6 of the apparatus of the present invention collides with the surface of the gas adsorbing sheet 4 through the gas diffusion layer 3 and the gas diffusion layer 3. The inside is dispersed in the direction of the arrow along the gas adsorbing sheet surface, flows out from the peripheral end surface of the gas diffusion layer 3 into the inner space of the container 3, and permeates the porous film forming the container wall, and is semi-sealed. It flows into the space. Further, part of the air that has flowed into the apparatus through the air inlet 6 passes through the gas adsorbing sheet and flows out into the internal space of the container 1.
When the air entering the semi-enclosed space is passed through the apparatus of the present invention as described above, the contaminant contained in the air is efficiently removed. That is, the pollutant gas in the air is adsorbed by the gas adsorbing sheet 4, and the dust in the air is trapped by the container wall and is prevented from flowing into the semi-sealed space. In this case, the air that has entered the apparatus through the air inlet 6 is mainly dispersed in the gas diffusion layer 3 having a low air resistance along the plane direction, so that the pressure loss when the air disperses the gas diffusion layer 3 is reduced. Is small. In addition, the pressure loss of the air when flowing from the space in the container 1 through the container wall into the semi-sealed space is small because the container wall is formed of a porous film having high gas permeability. Become.
[0022]
The semi-enclosed space in the present invention is a space having a breathing port composed of small through holes (its diameter is usually 1 to 5 mm) that adjusts and matches the pressure in the space to the external pressure (usually atmospheric pressure). That means. Such a semi-sealed space includes a disk storage chamber and a wafer storage case for various disks.
[0023]
【Example】
Next, the present invention will be described in more detail with reference to examples.
[0024]
Example 1
(1) Production of gas adsorption sheet
80 parts by weight of activated carbon chips having a particle size of 24-28 mesh (manufactured by Tsurumi Coal) and 20 parts by weight of polyethylene powder having an average particle diameter of 20 μm are mixed well and spread evenly in a stainless steel bat having a depth of 5 mm. This was placed in an oven at a temperature of 120 ° C. for 10 minutes, and the polyethylene powder was melted, bound with activated carbon, then taken out and cooled to room temperature to obtain an activated carbon sheet having a thickness of 5 mm. This had a sheet density of 0.7 g / cc and an activated carbon density of 0.5 g / cc. Moreover, the pressure loss when the air flow of the wind speed of 5.3 cm / sec was circulated through this was a 150 mm water column.
A 18 mm × 18 mm square sheet was hit from the activated carbon sheet and used as a gas adsorbing sheet.
The pressure loss is the pressure difference between the front surface and the back surface of the gas adsorbing sheet that occurs due to the resistance of the gas adsorbing sheet when air is passed through the gas adsorbing sheet at a wind speed of 5.3 cm / sec. Is obtained by measuring with a micro-pressure difference meter.
(2) Lamination of gas diffusion layer
A 18 mm × 18 mm square fiber sheet was laminated on one surface of the gas adsorption sheet obtained in (1) above, and was partially adhered using an adhesive to form a gas diffusion layer.
The fiber sheet is manufactured by Applied Extraction Technologies Inc. Delnet made by the company, the fiber is made of polypropylene, the part number is RO41-10PR, the weight is 44g / m ² The thickness of the fiber layer was 0.27 mm. The pressure loss when the air flow at a wind speed of 5.3 cm / second was passed through the fiber sheet was 2 mm water column. The pressure loss is the pressure difference between the front surface and the back surface of the sheet generated due to the resistance of the gas adsorbing sheet when air is passed through the fiber sheet at a wind speed of 5.3 cm / sec. It was obtained by measuring with a fine pressure difference meter.
(3) Production of container
An expanded porous PTFE film having an average pore diameter of 0.5 μm, a porosity of 80% and a thickness of 40 μm was used as a molding material, and this was molded into a container according to the process diagram shown in FIG. In this case, the mold space A was a rectangular space having a length of 20 mm, a width of 20 mm, and a depth of 10 mm, and a suction hole having a diameter of 3 mm was formed at the bottom of the mold. The suction force at the time of suction is the pressure of the vacuum system that communicates with the suction hole of the mold, and is expressed as 7.5 × 10 ^-Four It was Toll.
(4) Production of contaminant removal equipment
A circular double-sided pressure-sensitive adhesive sheet having a diameter of 30 mm and a thickness of 0.25 mm, in which a through hole having a diameter of 5 mm is formed at the center of the gas diffusion layer surface of the gas adsorption sheet having the gas diffusion layer obtained in (2) above. Used as a lid sheet and crimped to one side.
Next, the lid sheet obtained in this way is overlaid on the opening surface of the container obtained in (3) above, and is crimped to the peripheral edge (rib) of the container opening via the adhesive layer of the lid sheet. Thus, a pollutant removal apparatus having the structure shown in FIG. 1 was produced.
[0025]
Example 2
Dry blend of pulverized coconut shell activated carbon having a particle diameter of 50 μm and PTFE resin manufactured by Tsurumi Coal Co., Ltd. at a weight ratio of 60:40, extruding as a paste-like film by adding naphtha as an extrusion aid, And rolled into a 0.3 mm thick sheet. Next, the molded sheet was dried at 200 ° C. for 1 hour to remove the extrusion aid.
In this way, a gas adsorption sheet having a sheet density of 0.8 g / cc and an activated carbon density of 0.5 g / cc was obtained.
A contaminant removal apparatus was obtained in the same manner as in Example 1 except that this gas adsorption sheet was used.
[0026]
Example 3
In Example 2, a gas adsorbing sheet was obtained in the same manner except that the sheet-like material was stretched 1.5 times in the longitudinal and transverse directions at 200 ° C. This had a sheet density of 0.8 g / cc and an activated carbon density of 0.5 g / cc.
Since the gas adsorbing sheet is stretched, the air passage formed in the sheet is widened, the permeation of the gas to be adsorbed into the sheet is improved, and the gas adsorbing speed is improved.
A contaminant removal apparatus was obtained in the same manner as in Example 1 except that this gas adsorption sheet was used.
[0027]
【The invention's effect】
Each device produced as described above is composed of a high-density gas adsorbing sheet with a high gas adsorbent concentration, rather than a low-density fiber layer with a low gas adsorbent concentration. It has a high gas adsorption capacity. Further, the air flowing into the device is dispersed along the surface direction of the gas adsorbing sheet of the gas diffusion layer composed of a fiber layer having a low air resistance, and flows out from the peripheral end surface of the diffusion layer into the inner space of the container. From here, it penetrates the container wall with high gas permeability. Therefore, the pressure loss when air permeates through the apparatus of the present invention is low (usually 50 mm or less).
The device of the present invention has the above-described function, and is suitable as a contaminant removal device for a disc storage chamber having a breathing port. Contaminants are removed from the air entering the chamber through the mouth and clean air enters the disk chamber. This effectively prevents contamination by contaminants in the disk chamber.
The contaminant removal apparatus of the present invention can be preferably disposed in a magnetic recording disk device (HDD). In the contaminant removal apparatus of the present invention, a diffusion layer is formed on the gas adsorption sheet. This diffusion layer acts as a reinforcing material for the gas adsorption sheet. When the HDD is handled at home or the like, the sharp tweezers or the like may accidentally touch the gas adsorbing sheet from the air inlet of the contaminant removing device. In such a case, when a diffusion layer is formed on the gas adsorption sheet, the diffusion layer acts as a reinforcing layer or a protective layer of the gas adsorption sheet, and the tweezers are sandwiched between the gas adsorption sheet and the gas adsorption sheet It is prevented from being damaged.
[Brief description of the drawings]
FIG. 1 shows a schematic diagram of a contaminant removal apparatus of the present invention.
FIG. 2 is a manufacturing process diagram of the contaminant removal apparatus of the present invention.
FIG. 3 shows an external view of the pollutant removal apparatus of the present invention.
[Explanation of symbols]
1 container
2 peripheral edge of container opening
3 Gas diffusion layer
4 Gas adsorption sheet
5 Lid sheet
6 Air inlet
7 Mold
8 Porous film of synthetic resin

Claims (3)

A gas adsorbing sheet made of a synthetic resin porous film and having a diffusion layer on the surface thereof is accommodated in the container so that the diffusion layer is located on the container opening side, and the container opening is air-flowed at the center. It has a structure sealed with a lid film having an inlet, and the pressure loss of the gas adsorbing sheet is larger than the pressure loss of the diffusion layer, and the density of the adsorbent contained in the gas adsorbing sheet is An apparatus for removing contaminants contained in an air flow, characterized by being 0.4 to 1.5 g / cc. The contaminant removal apparatus according to claim 1, wherein the contaminant removal apparatus is disposed in a semi-enclosed space having a breathing opening for adjusting the internal pressure to the external pressure and facing the breathing opening. An apparatus for removing contaminants contained in air flowing into a semi-enclosed space, wherein the apparatus is disposed and used with its air inlet facing the breathing port of the semi-enclosed space. A magnetic recording disk device comprising the contaminant removing device according to claim 2.

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