JP5172165B2 - Gas removal filter medium, composite filter and filter element - Google Patents

Description

  The present invention relates to a filter used by being mounted on an air conditioner in a living environment such as an automobile or a home air cleaner, and in particular, a gas removal filter medium and a composite filter for simultaneously removing aldehyde gas, acid gas and alkaline gas. About. The present invention also relates to a filter element in which a gas removal filter medium or a composite filter is pleated.

  In living spaces such as residential rooms and offices in buildings, the interior materials and furniture used there contain a lot of chemical substances such as adhesives, and these chemicals such as toluene and formaldehyde It is known that volatile substances are generated. It is also known that acidic gases such as sulfur dioxide, nitrogen dioxide and acetic acid gas are generated as exhaust gas from automobiles and the like. These volatile substances and acid gases increase the occurrence of allergies represented by sick house syndrome and chemical hypersensitivity, and allergy countermeasures are an urgent issue. Therefore, for example, for housing and buildings, the Building Standards Law has been revised to limit the use of building materials such as plywood that volatilizes a lot of chemical substances, make the ventilation system mandatory, and allow the standard for formaldehyde to be 80 ppb. Legislation is being developed.

  In addition, it is known that volatile substances are generated from interior materials in the interior of automobiles where people spend a lot of time. There is a need for measures such as selecting materials that generate less volatile substances. However, it is inevitable to use adhesives that generate more or less volatile substances when assembling automobiles, and it is difficult to reduce the concentration of volatile substances in the interior of an automobile where the living space is narrow compared to the house. . In addition, it is possible to reduce the concentration of volatile substances by introducing outside air and ventilating, but acidic gases such as sulfur dioxide, nitrogen dioxide and acetic acid gas contained in the exhaust gas by the automobile itself, There was a problem that air was supplied into the car interior.

  Furthermore, it is known that when a car is left under a hot sun in summer or the like, the interior of the car rises to a temperature exceeding 80 ° C. on the dashboard and the room exceeding 60 ° C. At this high temperature, a very large amount of volatile substances are generated from the interior materials and adhesives, which causes a big problem that the passenger is exposed to a high concentration of volatile substances.

  Furthermore, in living spaces such as residential rooms, building offices, and automobile interiors, alkaline gases such as ammonia gas are generated from animals and plants and humans themselves, and alkaline gases such as rot odors caused by microorganisms and mold odors caused by molds. Occurred and caused odors and odors.

  On the other hand, a filter having a deodorizing function that holds a particulate adsorbent such as activated carbon is used in houses and automobiles against volatile substances, acid gases, alkaline gases, and the like. A multilayer deodorizing filter medium is known. Patent Document 1 describes the use of impregnated carbon obtained by attaching a chemical deodorant to the surface of a granular material having a physical adsorption action such as activated carbon or zeolite. For example, as chemical deodorants constituting the powder for acidic odor, alkali metal carbonates such as potassium carbonate, potassium hydrogen carbonate, sodium carbonate and sodium hydrogen carbonate, and amine compounds such as ethanolamine, hexamethylenediamine and piperazine Further, it is described that phosphoric acid, sulfuric acid, nitric acid, malic acid, citric acid, ascorbic acid and the like can be used as the chemical deodorant constituting the powder for alkaline odor.

  However, even if activated carbon, zeolite, or the above-mentioned impregnated coal is used, the filter removal efficiency is extremely low for formaldehyde and acetaldehyde, which may cause irritation of the eyes during operation and lead to an accident. Met. In addition, a technique for removing acid gas and alkaline gas together with aldehyde gases such as formaldehyde and acetaldehyde is not known, and a technique for removing these harmful substances together has been demanded.

Japanese Patent Laid-Open No. 11-57467

  The present invention relates to a filter that is used by solving the above-mentioned problems and installed in an air conditioner in a living environment such as an automobile or a domestic air cleaner, and more particularly, an aldehyde gas such as formaldehyde or acetaldehyde (hereinafter simply referred to as an aldehyde). It is an object of the present invention to provide a gas removal filter medium and a composite filter capable of removing an acid gas and an alkaline gas together, sometimes referred to as a gas). It is another object of the present invention to provide a filter element in which a gas removal filter medium or a composite filter is pleated.

In the invention according to claim 1, the means for solving the above-described problem has a gas removal particle layer in which gas removal particles having an average particle diameter of 0.147 to 1.65 mm are connected by a thermoplastic resin. And a gas removal filter medium having a thickness of 0.2 to 4 mm, wherein the gas removal particles include at least acid gas removal particles and alkaline gas removal particles, and the acid gas removal particles. Is attached after mixing potassium carbonate and / or potassium hydrogen carbonate and 2-amino-2 -hydroxymethyl- 1,3-propanediol as an acid gas remover, and the mass of the potassium carbonate and the above the sum of the mass of potassium hydrogen carbonate is 1 to 3.5 wt% based on the total weight of the acid gas removal particles, the 2-amino-2-hydroxymethyl-1,3-pro The diol has a mass of 2 to 7% by mass based on the total mass of the acid gas removal particles, and phosphoric acid as an alkaline gas removal agent is 1 to 3% of the total alkaline gas removal particles. It is a filter medium for gas removal characterized by adhering to 5 mass%.
The invention according to claim 1 relates to a filter used by being mounted on an air conditioner in a living environment such as an automobile or a home air cleaner, and can remove both acid gas and alkaline gas together with aldehyde gas. It is possible to provide a filter medium for gas removal.

Further, the invention according to claim 1 has an advantage that it is possible to efficiently remove acid gas and alkaline gas together with aldehyde gas at a particularly low cost.

Further, according to the first aspect of the invention, each gas removal particle can remove acid gas or alkaline gas together with aldehyde gas, so that the aldehyde removal particles and the acid gas removal particles are mixed. There is no need to mix the particles for aldehyde removal with the particles for alkaline gas removal, and there is no need to consider the dispersibility of the gas removal particles when they are mixed. Or since an aldehyde and alkaline gas can be removed, there exists an advantage that the more outstanding removal efficiency can be obtained.

In the invention according to claim 2, wherein the gas removal particle layer, according to claim 1 and a layer comprising an a layer consisting of at least the acid gas removal particles wherein the alkaline gas removing particles, characterized in that formed by stacking It is a filter medium for gas removal, and acid gas removal particles and alkaline gas removal particles are less likely to come into direct contact with each other, so that the acid gas removal agent and alkaline gas removal agent adhering to the gas removal particles are mutually neutralized. There is an advantage that the deactivation is reduced and the gas removal efficiency can be reliably increased.

Further, in the invention according to claim 1, wherein the acid gas removal agent is potassium carbonate and / or potassium hydrogen carbonate, the alkaline gas removing agent is gas removal filter material is phosphoric acid, aldehydes such as formaldehyde and acetaldehyde There is an advantage that it is particularly excellent in efficiently removing acid gas and alkaline gas together with gas at low cost.

In the invention according to claim 1, 2 - amino-2 -hydroxymethyl- 1,3-propanediol is attached to the acidic gas removing particles, and it is possible to perform better aldehyde gas removal. There is an advantage of being.

In the invention according to claim 3 , the gas removal particles according to claim 1 or 2 , wherein an average particle diameter of the gas removal particles is 0.1 to 1.0 times a thickness of the gas removal filter medium. There is an advantage that it is suitable for performing a pleating process because the average particle diameter of the gas removal particles is 0.1 to 1.0 times the thickness of the gas removal filter medium. .

According to a fourth aspect of the present invention, there is provided a filter element in which the gas removal filter medium according to any one of the first to third aspects is pleated, and the gas removal filter medium is pleated. Therefore, there are advantages that the life is extremely long and the pressure loss is also lower than in the case of the plate shape.

The invention according to claim 5 is a composite filter comprising the gas removal filter medium according to any one of claims 1 to 3 and a dust removal filter medium for removing dust, wherein the gas By stacking or laminating dust removal filter media upstream of the removal filter media to form a composite filter, it prevents dust from directly accumulating on the gas removal filter media, and aldehyde gas and acid gas related to the gas removal filter media , And the effect of preventing reduction in alkaline gas removal efficiency.

The invention according to claim 6 is a filter element characterized in that the composite filter according to claim 5 is formed by pleat folding, and since the composite filter is processed by pleat folding, In comparison, there are advantages that the life is extremely long and the pressure loss is also low.

  The present invention relates to a filter used by being mounted on an air conditioner in a living environment such as an automobile or a home air cleaner, and in particular, gas removal capable of removing acid gas and alkaline gas together with aldehyde gas. Filter media and composite filters can be provided. In addition, it is possible to provide a filter element in which a gas removal filter medium or a composite filter is pleated.

  Hereinafter, preferred embodiments of a gas removal filter medium, a composite filter, and a filter element according to the present invention will be described in detail.

  The filter medium for gas removal of the present invention is a sheet-like material having a gas removal particle layer in which gas removal particles are connected by a thermoplastic resin and having a thickness of 0.2 to 4 mm. The gas removal filter medium preferably has a breathable cover material on one side or both sides of the gas removal particle layer. The gas removal filter medium may be a composite filter having a dust removal filter medium for removing dust on one or both sides of the gas removal particle layer.

  As a form of the gas removal filter medium, for example, as shown in FIG. 1, gas removal comprising gas removal particles (3) and resin bodies (10) and (10 ′) connecting the gas removal particles (3). There is a gas removal filter medium (13) in which a breathable cover material (5) is laminated and integrated on both surfaces of the particle layer (8). In this example, the resin body (10) is provided on one side or both sides of the gas removal particle layer (8) in which the gas removal particles (3) are connected by a resin body (10 ′) made of heat-adhesive fibers to form a sheet. The air-permeable cover material (5) is bonded together.

  In order to obtain the gas removal particle layer (8) having such a structure, for example, the gas removal particles (3) are held in the voids of a mat-like material made of a resin component having air permeability and heat adhesion. Then, after that, the gas removal particles (3) can be adhered to the mat-like material by heat treatment. Further, for example, the gas removal particles (3) are held in the voids of the mat-like material made of a resin component having air permeability and heat-melting property, and then the mat-like material is melted by heat treatment, It can be obtained by connecting the gas removal particles (3). Examples of such a mat-like material having air permeability include porous materials such as nonwoven fabrics, woven fabrics, membranes, filter papers, sponges, etc. Among them, nonwoven fabrics are preferable because they have high air permeability. In the case of a non-woven fabric, for example, a non-woven fabric including an adhesive fiber composed of one component having a melting point of 160 ° C. or lower, or an adhesive composite fiber composed of two or more components including a low melting point component of 160 ° C. or lower can be applied. . In the present invention, the mat-like material is a resin body that connects the gas removal particles.

  As another method for obtaining the gas removal particle layer (8) having the above structure, for example, a mixture obtained by mixing a fiber having a short fiber length with heat adhesiveness or heat melting property and gas removal particles (3) is air permeable. The sheet material is deposited on the cover material (5) to form a sheet-like material, and then the sheet-like material is subjected to heat treatment so that the fibers exhibit adhesiveness or the fibers are melted to form a resin body. This resin body can be obtained by connecting the gas removal particles (3). In addition, when this method is used, the fiber length is preferably 1 to 15 mm, and more preferably 2 to 10 mm.

  As another form of the gas removal filter medium, for example, as illustrated in FIG. 2, a gas removal particle (3) and a resin body (hereinafter referred to as a connecting portion) for connecting the gas removal particle (3) (1) ), (1 ′), (10), and (10 ′) and an aggregated resin body (hereinafter referred to as a resin agglomerated part) (2) and (2 ′) on both sides of the gas removal particle layer (8) In addition, there is a gas removal filter medium (13) in which breathable cover materials (5) and (5 ′) are laminated and integrated. In this example, the gas removal particles (3) are connected by the resin bodies (1), (1 ′), (10), or (10 ′) to the gas removal particle layer (8) that is formed into a sheet shape. Cover materials (5) and (5 ') are laminated and integrated. More specifically, the gas-removed particles (3) are formed on one surface of the web composed of the connecting part (1) made of hot melt resin and the resin agglomerated part (2) via the resin agglomerated part (2). Is fixed.

  As another form of the gas removal filter medium, for example, as illustrated in FIG. 3, the gas removal particles (3) and (3 ′) are connected to the gas removal particles (3) and (3 ′). Gas composed of the bodies (1), (1 ′), (1 ″), (10), (10 ′) and (10 ″) and the aggregated resin bodies (2), (2 ′) and (2 ″) There is a gas removal filter medium (13) in which breathable cover materials (5) and 5 'are laminated and integrated on both surfaces of the removal particle layer 8. In this example, the gas removal particles (3) and (3' ) Are joined by the resin bodies (1), (1 ′), (1 ″), (10) and (10 ′) to form a laminated unit (4) and (4 ′) Are further laminated, and in this laminate, breathable cover materials (5) and (5 ′) are resin bodies (1), (1 ′), (10), and ( 10 ′) and agglomerated resin bodies (2), (2 ′) and (2 ″). More specifically, it is composed of a plurality of lamination units (4), and the lamination unit (4 ) Is attached to one surface of the web composed of the connecting part (1) made of hot melt resin and the resin agglomerated part (2), and the gas removal particles (3) are fixed via the resin agglomerated part (2). Thus, the other surface of the web and the gas removal particles (3 ′) constituting the other laminated unit (4 ′) are fixed to each other via the resin agglomerated portion (2 ″).

  Moreover, as a method for obtaining a gas removal filter medium having such a structure, for example, when the lamination unit (4) has two or more layers as shown in FIG. 3, gas removal is performed on the surface of the hot melt nonwoven fabric (10). After arranging the particles (3), a resin agglomerated part (2) is formed at the part where the hot melt nonwoven fabric and the gas removing particles are in contact with each other by heat treatment, and the resin agglomerated part (2) and the hot melt resin are connected. A first step of forming a web composed of the portion (1), and a second step of forming the laminated unit (4) by leaving only the gas removal particles fixed to the web among the gas removal particles. Then, the hot melt nonwoven fabric (10 ″) is laminated in contact with the gas removal particles (3) of the lamination unit (4), and then the gas removal particles (3 ′) are arranged on the surface of the hot melt nonwoven fabric (10 ″). After the first step and the second There is successively carried out method and steps. In addition, instead of the hot-melt nonwoven fabrics (10) and (10 ′) serving as both surfaces of the gas removal particle layer 8, a sheet in which the hot-melt nonwoven fabric is attached to the cover materials (5) and (5 ′) is used. In addition, a gas removal filter medium (13) in which the air-permeable cover materials (5) and (5 ′) are laminated and integrated can be obtained.

  As another form of the gas removal filter medium, for example, a gas permeable cover material is laminated and integrated on both sides of a gas removal particle layer formed by joining gas removal particles with a heat-fusible resin body to form a sheet. There is a gas removal filter medium. In order to obtain the gas removal particle layer having such a structure, for example, after mixing the gas removal particles and the heat-fusible resin powder, the gas removal particle layer is sandwiched between cover materials and used as a gas removal filter medium by heat treatment. There is.

  In the case of the above-described configuration shown in FIG. 2 or FIG. 3, gas with excellent pressure against formaldehyde, low molecular weight aldehyde, acid gas and alkaline gas is obtained because the surface of the gas removal particles is effectively used with low pressure loss. Removal efficiency can be exhibited. Further, the gas removal filter medium having such a structure has an advantage that it is easy to pleat because it has excellent flexibility while the gas removal particles are present at a high density.

〔式（１）中、Ｒ_１はメチル基またはヒドロキシメチル基、Ｒ_２はメチル基、エチル基またはヒドロキシメチル基である。〕 The gas removal particles applied to the present invention are used for removing unpleasant odorous substances in living environment, or remove gaseous pollutants contained in air or atmosphere in semiconductor or liquid crystal production facilities or clean rooms. The solid particles that can be used to adsorb gaseous substances or can be changed to substances that easily adsorb gaseous substances are used as acidic gas removing agents, alkaline gas removing agents, or the following general formula (1) The compounds represented by are attached alone or in admixture. Here, the solid particles to which the acidic gas removing agent is attached are referred to as acidic gas removing particles, and the solid particles to which the alkaline gas removing agent is attached are referred to as alkaline gas removing particles. It is necessary to include removal particles and alkaline gas removal particles. Further, some or all of the gas removal particles (that is, the acid gas removal particles, the alkaline gas removal particles, or the solid particles) (one or more of these three types) have the following general formula ( The compound represented by 1) is adhered.

Wherein (1), R ₁ is a methyl group or hydroxymethyl group, R ₂ is a methyl group, an ethyl group or a hydroxymethyl group. ]

  As the above-mentioned acidic gas removing agent, for example, alkali metal carbonates such as potassium carbonate, potassium hydrogen carbonate, sodium carbonate and sodium hydrogen carbonate, and amine compounds such as ethanolamine, hexamethylenediamine and piperazine are preferable. In addition, potassium carbonate and / or potassium hydrogen carbonate, which is excellent in acid gas removal ability, is more preferable. Moreover, as the above-mentioned alkaline gas removing agent, for example, phosphoric acid, sulfuric acid, nitric acid, malic acid, citric acid, ascorbic acid and the like are preferable, and among these, phosphoric acid having excellent alkaline gas removal ability is more preferable. Moreover, it is preferable that the acidic gas removing agent is potassium carbonate and / or potassium hydrogen carbonate and the alkaline gas removing agent is phosphoric acid.

Moreover, as a specific example of the compound represented by the above-mentioned general formula (1), for example, 2-amino-2-methyl-1-propanol represented by the following formula (2) in which R ₁ and R ₂ are methyl groups There is.

A specific example is 2-amino-2-methyl-1,3-propanediol in which R ₁ is a hydroxymethyl group and R ₂ is a methyl group. Further, there is 2-amino-2-ethyl-1,3-propanediol represented by the following formula (3), wherein R ₁ is a hydroxymethyl group and R ₂ is an ethyl group.

Further, as a specific example, 2 - amino-2 -hydroxymethyl- 1,3-propanediol represented by the following formula (4), in which R ₁ and R ₂ are hydroxymethyl groups, tris (hydroxymethyl) ) Aminomethane can be mentioned.

In the present invention, 2-amino-2-methyl-1-propanol, 2-amino-2-ethyl-1,3-propanediol and 2-aminodiol are considered in consideration of the availability of raw materials and cost. Amino-2 -hydroxymethyl- 1,3-propanediol is preferred, and 2-amino-2 - ethyl-1,3-propanediol and 2-amino-2 -hydroxymethyl- 1 which are more reactive with aldehydes. , 3-propanediol is more preferred. Moreover, when both are compared, it is also possible to employ 2-amino-2-ethyl-1,3-propanediol, which is superior in terms of solubility in water. It is also preferable to employ 2 - amino-2 -hydroxymethyl- 1,3-propanediol, which does not have a problem of re-dissolving due to adhesion of moisture or the like and leaving the solid particles.

In the present invention, the compound of the above general formula (1), the acidic gas removing agent, and the alkaline gas removing agent are included in the solid particles. Examples of such solid particles include activated carbon, zeolite, There are chemical adsorbents, ion exchange resins, catalysts such as photocatalysts, and the like, and one or two or more of these can be selected as appropriate. In the present invention, it is preferable to select activated carbon having excellent ability to adsorb various gaseous substances. Further, for example, when activated carbon is selected, a porous material having a specific surface area of 200 m ² / g or more is preferable, 500 m ² / g or more is more preferable, and 800 m ² / g or more is more preferable.

  In the present invention, the particle diameter of the gas removal particles needs to be 0.147 mm (100 mesh) to 1.65 mm (10 mesh) in order to realize both high efficiency and low pressure loss. The average particle size is more preferably 0.212 mm (70 mesh) to 1.0 mm (16 mesh). If gas removal particles with a fine average particle diameter of less than 0.147 mm (100 mesh) are used, the initial gas removal efficiency can be increased with respect to aldehyde gas, acid gas, and alkaline gas, but the pressure loss is large. The problem of becoming. In addition, when gas removal particles having a coarse average particle diameter exceeding 1.65 mm (10 mesh) are used, initial gas removal efficiency becomes insufficient with respect to aldehyde gas, acid gas, or alkaline gas. There is.

  In the present invention, the compound represented by the general formula (1) is attached to the gas removal particles (that is, the acid gas removal particles, the alkaline gas removal particles, or the solid particles). The total of the mass of the removal agent, the mass of the alkaline gas removal agent, and the mass of the compound represented by the following general formula (1) includes 0.02 to 20 mass% with respect to the mass of the entire gas removal particles. It is preferable. Moreover, it is more preferable to contain 0.5-15 mass% in the said solid particle, and it is still more preferable to contain 1-10 mass%. If it is less than 0.02% by mass, the removal efficiency of aldehyde gas, acid gas or alkaline gas may be insufficient. If it exceeds 20% by mass, the removal efficiency of aldehyde gas, acid gas or alkaline gas is excellent, but solid particles The function of the device itself may be reduced. For example, the removal efficiency of organic gases such as toluene (excluding aldehyde gas) may be reduced.

  Moreover, as long as the said gas removal particle contains the compound of the above-mentioned general formula (1), an acidic gas removal agent, and an alkaline gas removal agent by adhesion etc., the compound of general formula (1) The content ratio is not particularly limited, but considering the ability to remove aldehyde gas and the ability to remove organic gas other than aldehyde gas, it is preferable to include 0.01 to 19% by mass with respect to the mass of the entire gas-removed particles, It is more preferable to contain 0.5-15 mass%, and it is still more preferable to contain 1-12 mass%. If it is less than 0.01% by mass, the removal efficiency of aldehyde gas may be insufficient. If it exceeds 19% by mass, the removal efficiency of aldehyde gas is excellent, but organic gas such as toluene (excluding aldehyde gas) is removed. Efficiency may be reduced.

  Moreover, as long as the said gas removal particle is contained in the said solid particle by adhesion etc. by the adhesion | attachment etc. of the compound of the above-mentioned General formula (1), an acid gas removal agent, and an alkaline gas removal agent, the ratio which an acid gas removal agent is contained in Is not particularly limited, but it is preferable to include 0.01 to 12% by mass, and more preferably 0.5 to 10% by mass with respect to the total mass of the gas-removed particles, considering the acid gas removal ability. 1 to 8% by mass is more preferable. If it is less than 0.01% by mass, the acid gas removal efficiency may be insufficient. If it exceeds 12% by mass, the acid gas removal efficiency will approach the limit. On the other hand, since the content of the compound of the general formula (1) decreases, the ability to remove aldehyde gas may decrease.

  Moreover, as long as the said gas removal particle contains the compound of the above-mentioned General formula (1), an acidic gas removal agent, and an alkaline gas removal agent by adhesion etc. in the said solid particle, the ratio in which an alkaline gas removal agent is contained Is not particularly limited, but when considering the ability to remove alkaline gas, it is preferably included in an amount of 0.01 to 12% by mass, more preferably 0.5 to 10% by mass, based on the total mass of the gas removal particles 1 to 8% by mass is more preferable. If the amount is less than 0.01% by mass, the alkaline gas removal efficiency may be insufficient. If the amount exceeds 12% by mass, the alkaline gas removal efficiency will approach the limit, and further improvement in efficiency cannot be expected. On the other hand, since the content of the compound of the general formula (1) decreases, the ability to remove aldehyde gas may decrease.

  In the present invention, in order to attach the compound of the general formula (1) and the acidic gas removing agent to the solid particles, for example, the compound of the general formula (1) and the acidic gas removing agent are preferably separately or mixed. Is placed as a 0.5-40% aqueous solution, more preferably as a 1-30% aqueous solution, even more preferably as a 1-20% aqueous solution, and the aqueous solution is sprayed on the solid particles and then dried. Can be obtained.

In the present invention, in order to adhere the compound of the general formula (1) and the alkaline gas removing agent to the solid particles, for example, the compound of the general formula (1) and the alkaline gas removing agent are separately or mixed. And preferably 0.5 to 40% aqueous solution, more preferably 1 to 30% aqueous solution, still more preferably 1 to 20% aqueous solution, and the aqueous solution is sprayed on the solid particles. It can be obtained by drying. In addition, you should avoid mixing an acidic gas removal agent and an alkaline gas removal agent, and adhering to the said solid particle. This is because when an acid gas removing agent and an alkaline gas removing agent are mixed, these removing agents are deactivated by a neutralization reaction, and the gas removing ability of each removing agent may be reduced. Further, when the compound of the general formula (1) and the alkaline gas removing agent are mixed, the removing agent may be deactivated by reacting with each other in some cases, and the gas removing ability of each removing agent may be reduced. For example, when 2-amino-2 -hydroxymethyl- 1,3-propanediol is selected as the compound of the general formula (1) and phosphoric acid is selected as the alkaline gas removal agent, the gas removal depends on the mixing ratio. In such a case, it is desirable to avoid mixing the compound of the general formula (1) and the alkaline gas removing agent because the capacity may be lowered.

  The gas removal particles are not particularly limited to the form of adhesion as long as the solid particles contain the compound of the general formula (1), the acid gas removal agent, and the alkaline gas removal agent by adhesion or the like. For example, the compound of the general formula (1), the acid gas removing agent, and the alkaline gas removing agent may be separately or mixed and adhered to one or more of the solid particles. Further, for example, the gas removal particles are composed of two or more kinds of solid particles, and the compound of the general formula (1), the acid gas removal agent, and the alkaline gas removal agent are separately or mixed with only one kind of solid particles. It is also possible to adhere. For example, as shown in FIG. 3, when there are two or more stacking units, the compound of the general formula (1), the acidic gas removing agent, and the alkaline gas removing agent are attached to the entire gas removing particles. As long as it is contained in the solid particles, it is possible to change the adhesion ratio of the compound of the general formula (1), the acidic gas removing agent, and the alkaline gas removing agent in each laminated unit. Moreover, the said gas removal particle | grains can also contain another chemical | medical agent, unless the effect by this invention is impaired besides the compound of General formula (1). In general, agents that remove different substances may react with each other when mixed with each other, and the effect may be lost. However, the compound of the general formula (1) and the acid gas removing agent react with each other. Since there is no property, it can be mixed and dissolved, and since the adhering process only needs to be performed once, there is a great time and economic merit.

  As more specific embodiments, for example, as illustrated in FIG. 4 and FIG. 5, solid particles (3a) containing only the compound of the general formula (1) and solid particles (3b) containing only the acidic gas removing agent ) And solid particles (3c) containing only an alkaline gas removal agent, and as a result, a form containing 0.02 to 20% by mass with respect to the mass of the entire gas removal particles is possible. Further, for example, as illustrated in FIG. 6, solid particles (3ab) containing a material in which a compound of general formula (1) and an acid gas removing agent are mixed in advance, and solid particles (3c) containing only an alkaline gas removing agent As a result, a form containing 0.02 to 20% by mass with respect to the total mass of the gas removal particles is possible. If it is the latter form, since it becomes possible for each gas removal particle to remove acidic gas (or alkaline gas) with aldehyde gas, the particle for aldehyde gas removal and the particle for acid gas removal are mixed. It is not necessary to use such a time-consuming process, and more than one gas can be removed by individual particles, resulting in fewer gas removal spots due to particle dispersibility and better removal efficiency compared to the former There is an advantage that can be obtained.

  Further, it is preferable that the gas removal particle layer is formed by laminating at least a layer made of the acid gas removal particles and a layer made of the alkaline gas removal particles. Here, the layer composed of the acid gas removing particles is a solid particle (3b) containing only the acid gas removing agent or a solid particle (3ab) containing a substance obtained by previously mixing the compound of the general formula (1) and the acid gas removing agent. ). The layer made of the alkaline gas removing particles may be solid particles (3c) containing only the alkaline gas removing agent. With such a structure, the acid gas removing particles and the alkaline gas removing particles are less likely to come into direct contact with each other, so that the acid gas removing agent and the alkaline gas removing agent attached to the gas removing particles are neutralized with each other. As a result, the deactivation is reduced, and there is an advantage that the gas removal efficiency can be reliably increased. More specifically, as illustrated in FIG. 7, a layer (4) composed of solid particles (3ab) containing a substance obtained by previously mixing a compound of the general formula (1) and an acid gas remover, and an alkaline gas remover Examples thereof include a gas removal filter medium in which a layer (4 ′) made of solid particles (3c) containing only gas is laminated.

  The thickness of the gas removal filter medium of the present invention needs to be 0.2 to 4 mm, preferably 0.3 to 3 mm, preferably 0.4 to 2 mm, in consideration of performing pleating. Is more preferable, and it is still more preferable that it is 0.5-2 mm. If it is less than 0.2 mm, the removal efficiency of aldehyde gas and acid gas becomes insufficient. On the other hand, when the length exceeds 4 mm, when pleating is performed, there are many portions (hereinafter referred to as dead space) which do not contribute to the filtration of the gas or have very little contribution, and on the contrary, the removal efficiency of aldehyde gas and acid gas is increased. It becomes insufficient. Moreover, as a relationship between the average particle diameter of the gas removal particles and the thickness of the filter medium for gas removal, the average particle diameter of the gas removal particles is 0.1 to 1.0 times the thickness of the filter medium for gas removal. It is preferable. The average particle diameter of the gas removal particles is more preferably 0.2 to 0.8 times the thickness of the gas removal filter medium. The thickness is a value obtained by the test method specified in JIS L1913-1998 6.1.2A method.

  In the gas removal filter medium of the present invention, the proportion of the gas removal particles and the thermoplastic resin is preferably 60 to 95% by mass of the gas removal particles and 40 to 5% by mass of the thermoplastic resin. More preferably, the gas removal particles are 70 to 92% by mass and the thermoplastic resin is 30 to 8% by mass, the gas removal particles are 80 to 90% by mass, and the thermoplastic resin is 20 to 10% by mass. More preferably, it consists of. When the gas removal particles are less than 60% by mass, the removal efficiency of aldehyde gas or acid gas may be lowered. Further, when the thermoplastic resin is less than 5% by mass, there is a problem that the gas removal particles cannot be sufficiently connected and the gas removal particles fall off.

  The composite filter of the present invention is a composite filter in which the gas removing filter medium and a dust removing filter medium for removing dust are laminated. By stacking or laminating a dust removing filter medium upstream of the gas removing filter medium to form a composite filter, it is possible to prevent dust from directly depositing on the gas removing filter medium. There is an effect of remarkably preventing a decrease in the removal efficiency of the acid gas.

  The aspect of the filter material for removing dust is not particularly limited as long as it is a breathable material. For example, a fiber base material such as a woven fabric, a knitted fabric, a net, or a non-woven fabric can be applied. Among these, a non-woven fabric is particularly preferable because it can efficiently use the total area of the fiber surface widely and has many small voids formed by the fibers.

  The nonwoven fabric (hereinafter referred to as the nonwoven fabric substrate) as the fiber substrate is not particularly limited, and the structure of the nonwoven fabric substrate is typically a fiber length of 15 to 100 mm and a crimp number of 5 to 30 / inch. Generally called a dry method, in which a fiber called a staple fiber is formed on a fiber web using a card machine or an air array device, and then the constituent fibers are bonded together using an adhesive fiber or an adhesive. There is a nonwoven fabric obtained by a manufacturing method. Since the nonwoven fabric by the dry method has many fibers oriented in the thickness direction, there is an advantage that the thickness is large and the thickness is not easily crushed. In addition, the staple fiber is crimped so that it can be opened by a card machine or the like, so that it becomes a bulky nonwoven fabric base material and has an advantage of excellent repulsive force in the thickness direction against compression. is there.

  Moreover, the nonwoven fabric formed not only by a dry method but by the manufacturing method of arbitrary nonwoven fabrics, for example, a wet method, a spun bond method, a melt blow method, an electrostatic spinning method, a flash spinning method etc. is applicable. In the case of the wet method, for example, from a slurry containing fibers made of thermoplastic resin using a paper machine of a horizontal long net method, an inclined wire type short net method, a circular net method, or a long net / circular net combination method. A method of rolling up the fiber sheet can be employed. Specifically, there is a method in which constituent fibers are bonded to a fiber sheet after paper making using an adhesive. Alternatively, there is a method in which adhesive fibers made of a thermoplastic resin are mixed in a slurry, and after the paper making, the constituent fibers are bonded to each other using the adhesive fibers.

  In the case of the spunbond method, for example, a fiber made of a thermoplastic resin is spun from a nozzle to form a fiber fleece made of a long fiber, and then the fiber fleece is pressed between a heating roll having irregularities and a smooth roll. However, there is a method of forming a nonwoven fabric base material in which fibers made of a thermoplastic resin are partially fused. Further, for example, there is a method in which a fiber made of a thermoplastic resin is spun from a nozzle to form a fiber fleece made of a long fiber, and then the constituent fibers are bonded together using an adhesive made of a thermoplastic resin. Alternatively, there is a method in which core-sheath type long fibers made of two kinds of resin components having different melting points are spun from a nozzle, and then the constituent fibers are bonded by bonding using a low melting point sheath component as an adhesive component. Also, when a fiber made of thermoplastic resin is spun from a nozzle to make a fiber fleece made of a long fiber, an adhesive staple fiber made of a thermoplastic resin is blown into the fiber fleece in which the long fiber and the short fiber are integrated. Then, there is a method of bonding the constituent fibers by bonding. In the case of a nonwoven fabric substrate using staple fibers, since many fibers are oriented in the thickness direction, there is an advantage that the thickness is large and the thickness is not easily crushed. In addition, there is an advantage of excellent repulsive force in the thickness direction against compression.

  In the case of electrostatic spinning or flash spinning, for example, a fiber made of a thermoplastic resin is spun from a nozzle into a fiber fleece, and then the constituent fibers are bonded using an adhesive made of a thermoplastic resin. There is a way to join.

  Moreover, in these nonwoven fabric manufacturing methods, it is also possible to use a method in which fibers are entangled with each other by the action of a needle or a water flow to bond the fibers to the formed fiber web, fiber sheet, or fiber fleece. Moreover, it is also possible to use together the method of couple | bonding fibers by heat sealing | fusion entirely or partially using a heating roll.

  The fibers constituting the nonwoven fabric substrate are not particularly limited, and synthetic fibers made of thermoplastic resin, semi-synthetic fibers such as rayon, natural fibers such as cotton and pulp fibers, or inorganic fibers such as metals can be applied. Although it is possible, in view of durability and workability, it is preferable to include fibers made of a thermoplastic resin. The fibers made of thermoplastic resin include synthetic fibers that are generally used in the production of nonwoven fabrics. For example, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, polyamide fibers such as nylon 6 and nylon 66, polypropylene, and polyethylene. And the like, polyolefin fibers such as polyacrylonitrile, acrylic fibers such as polyacrylonitrile, and polyvinyl alcohol fibers. Moreover, when further improving the filtration performance of a filter, it is preferable to apply polyolefin fiber excellent in charging property among these fibers.

  Further, the fiber made of a thermoplastic resin can be a heat-adhesive fiber. Examples of heat-bondable fibers include fibers composed of a single resin component that has a lower melting point than other fibers and can be bonded to other fibers, and other fibers that have a lower melting point than other fibers. There are composite fibers having low melting point components that can be made on the fiber surface. Such composite fibers include, for example, core-sheath type and side-by-side type composite fibers having a low melting point component on the fiber surface, and the material thereof is, for example, copolymer polyester / polyester, copolymer There are composite fibers made of a combination of fiber-forming polymers such as polypropylene / polypropylene, polypropylene / polyamide, polyethylene / polypropylene, polypropylene / polyester, and polyethylene / polyester. In addition, the ratio which occupies for the whole nonwoven fabric base material of the said heat bondable fiber can be used in arbitrary ratios, unless the effect of this invention is impaired.

  Moreover, 0.1-30 dtex is preferable, as for the average fineness of the fiber in the said nonwoven fabric base material, 0.5-20 dtex is more preferable, and 0.5-10 dtex is still more preferable.

  As described above, it is possible to make a composite filter using various nonwoven fabric base materials according to the purpose of use, but considering the application of pleating to the composite filter, the thickness of the composite filter of the present invention is: It is preferably 0.2 to 4 mm, more preferably 0.4 to 3 mm, and still more preferably 0.6 to 2 mm. If it is less than 0.2 mm, the removal efficiency of aldehyde gas or acid gas may be insufficient, and if it exceeds 4 mm, it does not contribute to gas filtration or contributes when pleated. There may be an extremely small portion (hereinafter referred to as a dead space), and the removal efficiency of aldehyde gas or acid gas may be insufficient.

The surface density of the fiber base material is preferably from 5 to 100 g / ^{m 2,} and more preferably 10 to 80 g / ^{m 2.}

  The filtration performance of the dust removing filter medium preferably functions as a coarse dust removing filter. Specifically, in the test method defined in ASHRAE 52.-1992, using SAE FINE dust, When evaluated by the method, when the test condition is a wind speed of 0.25 m / sec, the particle collection average efficiency is preferably 50 to 99%, the particle collection average efficiency is preferably 60 to 99%, It is more preferable that the collection average efficiency is 70 to 99%. When the average particle collection efficiency is less than 50%, the coarse dust removal is insufficient, and when the average particle collection efficiency exceeds 99%, the pore diameter of the filter medium for dust removal becomes too fine. In some cases, the pressure loss before and after the filter material for dust removal reaches a limit and the life is shortened, and the filter cannot be used as a filter for removing coarse dust. SAE FINE dust is dust that conforms to the test dust specified in A2 (fine) of ISO12103-1 (1997). Further, in the test method defined in JIS B9908 Type 1, when the evaluation is performed by a counting method using atmospheric dust of 0.3 μm, the particle collection average efficiency is 5 to 5 when the test condition is a wind speed of 0.1 m / sec. It is preferably 50%, the particle collection average efficiency is preferably 10 to 50%, and the particle collection average efficiency is more preferably 20 to 50%.

  The pressure loss of the dust removing filter medium is preferably as small as possible while ensuring the above-mentioned filtration performance. The initial pressure loss (Pa) is 0.05 to 10 Pa when measured at a wind speed of 0.1 m / sec. Is preferable, 0.1-7 Pa is more preferable, and 0.5-5 Pa is still more preferable.

  Considering the above requirements, it is preferable to use a nonwoven fabric base material having an effect of excellent dust removal efficiency even if the thickness is small, as the nonwoven fabric base material of the dust removing filter medium used for the composite filter. A melt blown nonwoven fabric is a preferred form for such a nonwoven fabric substrate. Specifically, the average fiber diameter of the melt blown nonwoven fabric is preferably 0.1 to 50 μm, more preferably 0.5 to 40 μm, and still more preferably 1 to 30 μm. The material is preferably made of polypropylene resin, and further charged by corona charge or the like, and the counting method efficiency is 5 to 40%, preferably 10 to 30% (atmospheric dust 0.3 to 0.5 μm, wind speed 10 cm / It is preferable to use the filter medium for removing dust of s).

  In the filter element of the present invention, the gas removal filter medium is pleated, or the composite filter is pleated. Specifically, as illustrated in FIG. 8 or FIG. 9, the filter element of the present invention has a filter material for gas removal or a composite filter (21) pleated, and the pleated shape is formed by the shape retaining member (22a). The filter element (20) is held. FIG. 8 also illustrates an example in which the shape retaining member (22b) is mounted in the direction of arrow A on the end surface of the pleated filter (21) that intersects the pleated ridgeline direction. The pleating process of the gas removal filter medium or the composite filter is not limited as long as it is folded into a zigzag shape. This folding method is a method using a pleating machine such as a reciprocating type or a rotary type, or a zigzag shape. There is a method of pressing with a die.

  The shape-retaining member is not particularly limited as long as the pleated shape can be maintained. For example, a sheet-like material such as a woven or knitted fabric, a nonwoven fabric, a synthetic resin sheet, a foamed sheet, paper, a metal material, or a composite thereof. Can be applied. Of these, non-woven fabrics are particularly preferable because they are excellent in strength, excellent in cushioning properties when the filter element is attached to the rigid frame, and excellent in sealing performance with the rigid frame. Specifically, these sheet-like materials can be attached to an end surface intersecting with the pleated ridge line direction by heat-sealing or adhering via an adhesive or an adhesive sheet. The shape-retaining member is not limited to a sheet-like member, and can be formed by foaming by attaching a foamable resin or the like. Further, the shape retaining member can be mounted not only on the end face intersecting with the pleated line direction but also on an end face parallel to the pleated line direction.

  Before or after the pleating process, as illustrated in FIG. 8 or FIG. 9, the gas removing filter medium or the composite filter (21) is parallel to the direction intersecting the pleated ridge line direction with an interval. It is also preferable to provide a separator (24) to which a linear resin is attached to prevent the slope of the pleat mountain from coming into contact and forming a dead space. As shown in these figures, it is preferable that the linear resin is intermittently provided at the peak of the pleat and not at the valley of the pleat. It is also a preferable aspect to provide on both surfaces.

  The filter element preferably has a large number of pleats (23) as illustrated in FIG. 8, and specifically, as shown in FIG. 5-150 mm is preferable, 8-100 mm is more preferable, and 10-60 mm is still more preferable. Moreover, 1-20 mm is preferable, as for the pitch P of a pleat (23), 2-15 mm is more preferable, and 3-10 mm is still more preferable. Moreover, it is preferable that ratio P / H of pitch P (mm) and height H (mm) is 0.05-0.7, it is preferable that it is 0.05-0.5, 0.05 More preferably, it is -0.3. If the P / H is less than 0.05, the pleat angle becomes too small, and the pleat angle is widened by the wind pressure and adheres to adjacent pleats, resulting in a dead space, which reduces the aldehyde gas removal effect. There is. Moreover, when P / H exceeds 0.5, the number of pleats decreases, the area of the entire filter medium decreases, and the aldehyde gas and acid gas removal effect may decrease. If the height of the pleats exceeds 150 mm, the pleat angle becomes too small, and the pleat angle is widened by the wind pressure and adheres to the adjacent pleats, resulting in a dead space. On the contrary, the effect of removing aldehyde gas and acid gas is reduced. May end up.

  The overall size of the filter element is such that the dimension of one side of the air inflow surface is 80 to 500 mm in the case of a filter element that is used by being mounted on an air conditioner in a living environment such as an automobile or a home air cleaner. Is preferable, 100 to 400 mm is more preferable, and 150 to 300 mm is still more preferable. Moreover, 5-100 mm is preferable, 8-50 mm is more preferable, and 10-30 mm is still more preferable. Also, in the case of filter elements used as aldehyde gas removal filters such as package filters, fan coil units, central air conditioning filter units, etc. in air purifiers installed in buildings, factories, offices, etc. The dimension of one side is preferably 200 to 1500 mm, more preferably 300 to 1000 mm, and still more preferably 400 to 700 mm. Moreover, 10-500 mm is preferable, 20-400 mm is more preferable, and 30-300 mm is still more preferable.

  When the filter element is applied to an air conditioner, the filter element can be used by being mounted on a rigid frame. The rigid frame is not particularly limited as long as it is a rigid material, and wood, metal, plastic, or the like is applied, and wood is preferable when incinerated and discarded after several washing and regeneration.

  The gas removal performance of the filter element can be evaluated by DIN 71460 Part II. Specifically, for the aldehyde gas, the removal efficiency in one pass is measured using 3 ppm of acetaldehyde gas. The acetaldehyde gas removal efficiency is preferably 20% or more, more preferably 30% or more, and still more preferably 40% or more. In addition, for other organic gases, the behavior is often different from that of aldehyde gas. For this reason, the removal efficiency in one pass is measured by using 80 ppm gas of toluene, typically toluene gas. The removal efficiency of this toluene gas is preferably 50% or more, more preferably 60% or more, and further preferably 70% or more. Moreover, with respect to acidic gas, the removal efficiency in one pass is measured using 30 ppm gas of sulfur dioxide. The removal efficiency of this sulfur dioxide gas is preferably 25% or more, more preferably 30% or more, and further preferably 50% or more.

  As described above, according to the present invention, the present invention relates to a filter that is used by being mounted on an air conditioner in a living environment such as an automobile or a home air cleaner, and in particular, efficiently removes acid gas together with aldehyde gas at low cost. It has become possible to provide a filter medium for gas removal and a composite filter that can be used. In addition, it is possible to provide a filter element in which a gas removal filter medium or a composite filter is pleated.

  Examples of the present invention will be described below, but these are only suitable examples for facilitating the understanding of the present invention, and the present invention is not limited to the contents of these examples.

(Dust removal filter media pressure drop test method)
As the initial pressure loss (Pa), a value measured at a wind speed of 0.1 m / sec is used.

(Dust removal filter medium filtration performance test method-counting method)
In the test method stipulated in JIS B 9908 Type 1, 0.3 μm of atmospheric dust is supplied at a wind speed of 0.1 m / sec to determine the particle collection average efficiency (%).

(Aldehyde gas removal performance test)
In the test method specified in DIN 71460 Part II, after adjusting the test air so that the acetaldehyde concentration is 3 ppm, the test air is supplied at an air volume of 280 m ³ / hr to improve the initial removal efficiency of acetaldehyde gas ( %) To obtain the aldehyde gas removal efficiency. For detection of the aldehyde gas concentration, a multi-gas monitor 1302 manufactured by B & K is used.

(Organic gas removal performance test)
In the test method specified in DIN 71460 Part II, after adjusting the test air so that the toluene concentration becomes 80 ppm, the test air is supplied at an air volume of 280 m ³ / hr to improve the initial removal efficiency of toluene gas ( %) To determine the organic gas removal efficiency. For detection of the concentration of toluene gas, an FT-IR analyzer EQINOX55 manufactured by BRUKER is used.

(Acid gas removal performance test)
In the test method stipulated in DIN 71460 Part II, after adjusting the test air so that the sulfur dioxide concentration becomes 30 ppm, the test air is supplied at an air volume of 280 m ³ / hr, and the initial removal efficiency of sulfur dioxide gas (%) To obtain the acid gas removal efficiency. A multi-gas monitor type 1302 manufactured by B & K is used for detecting the concentration of sulfur dioxide gas. In addition, the time when the sulfur dioxide gas removal efficiency decreased and reached 10% was defined as the sulfur dioxide removal life. Subsequently, the multiplication factor of the sulfur dioxide removal life of each example was obtained with respect to the sulfur dioxide removal life of Example 1.

(Alkaline gas removal performance test)
In the test method specified in DIN 71460 Part II, after adjusting the test air so that the ammonia concentration becomes 30 ppm, the test air is supplied at an air volume of 280 m ³ / hr to improve the initial removal efficiency of ammonia gas ( %) To obtain the alkaline gas removal efficiency. For detection of ammonia gas concentration, a multi-gas monitor 1302 manufactured by B & K is used. The time when the ammonia gas removal efficiency was reduced to 10% was defined as the ammonia removal life. Next, the ratio of the ammonia removal life of each example to the ammonia removal life of Example 1 was determined.

(Raw material adjustment 1a)
2 - amino-2 -hydroxymethyl- 1,3-propanediol represented by the following formula (4), in which R ₁ and R ₂ are hydroxymethyl groups in potassium carbonate and the general formula (1) described above, Dissolved in water to give 1.2%, 3%, 4%, 8.5% aqueous solutions. Then, after spraying this aqueous solution on commercially available activated carbon particles classified to a particle size of 0.25 to 0.5 mm, the activated carbon particles were dried to give 2-amino-2 -hydroxymethyl- 1,3-propanediol and carbonic acid. Four types of gas removal particles A, B, C and D having different potassium adhesion ratios were obtained. In these gas removal particles A, B, C and D, potassium carbonate is 1% by mass, 2.5% by mass, 3.5% by mass and 8.5% by mass with respect to the total mass of each gas removal particle. It was made to adhere in the ratio. In addition, 2-amino-2 -hydroxymethyl- 1,3-propanediol was attached at a ratio of 2% by mass, 5% by mass, 7% by mass, and 15% by mass.

(Raw material adjustment 1b)
Potassium bicarbonate and 2 - amino-2 -hydroxymethyl- 1,3-propanediol represented by the above formula (4) were dissolved in water to obtain a 4% aqueous solution. Next, this aqueous solution was sprayed on commercially available activated carbon particles classified to a particle size of 0.355 to 0.85 mm, and then the activated carbon particles were dried to obtain gas removal particles E. The gas removal particles E have a ratio of 3.5% by mass of potassium bicarbonate and 7% by mass of 2 - amino-2 -hydroxymethyl- 1,3-propanediol with respect to the mass of the entire gas removal particles. Attached.

(Raw material adjustment 1c)
Potassium carbonate, potassium hydrogen carbonate and 2 - amino-2 -hydroxymethyl- 1,3-propanediol represented by the above formula (4) were dissolved in water to give a 4% aqueous solution. Subsequently, after spraying this aqueous solution on commercially available activated carbon particles classified into particle diameters of 0.25 to 0.5 mm, the activated carbon particles were dried to obtain gas removal particles F. The gas removal particles F include 1.8% by mass of potassium carbonate, 1.7% by mass of potassium hydrogen carbonate, 2-amino-2 -hydroxymethyl- 1 with respect to the total mass of the gas removal particles. , 3-propanediol was deposited in a proportion of 7% by weight.

(Raw material adjustment 2a)
Phosphoric acid was dissolved in water to obtain 1.2%, 3%, 4%, and 8.5% aqueous solutions. Subsequently, after spraying this aqueous solution on commercially available activated carbon particles classified to a particle size of 0.25 to 0.5 mm, the activated carbon particles are dried, and four kinds of gas removal particles A ′ and B ′ having different adhesion ratios of phosphoric acid. , C ′ and D ′ were obtained. In these gas removal particles A ′, B ′, C ′ and D ′, phosphoric acid is 1% by mass, 2.5% by mass, 3.5% by mass and 8.% by mass with respect to the total mass of each gas removal particle. It was made to adhere in the ratio of 5 mass%.

(Raw material adjustment 2b)
Phosphoric acid was dissolved in water to make a 4% aqueous solution. Subsequently, this aqueous solution was sprayed on commercially available activated carbon particles classified to a particle size of 0.355 to 0.85 mm, and then the activated carbon particles were dried to obtain gas removal particles E ′. Phosphoric acid was attached to the gas removal particles E ′ at a ratio of 7% by mass with respect to the mass of the gas removal particles as a whole.

(Raw material adjustment 3)
A thermoplastic polyamide-based resin (melt index at 190 ° C .: 80) is melt-spun to form a spider web-shaped hot melt nonwoven fabric with a surface density of 20 g / m ² , and immediately, a fiber diameter of 10 to 30 μm and a surface density of 20 g. / M ² , thickness 0.12 mm, pressure loss 1.0 Pa (wind speed 10 cm / s) is attached to a spunbonded nonwoven fabric made of polyester fiber, and a hot melt nonwoven fabric is adhered to a cover material A having a surface density of 40 g / m ² Got.

(Raw material adjustment 4)
A melt blown nonwoven fabric made of a polypropylene resin having a fiber diameter of 3 to 30 μm, a surface density of 20 g / m ² , a thickness of 0.5 mm, and a pressure loss of 2 Pa (wind speed of 10 cm / s) was obtained by a melt blow method. Furthermore, charging processing by corona charge was performed to obtain a dust removing filter medium A having a counting method efficiency of 20% (atmospheric dust 0.3 to 0.5 μm, wind speed 10 cm / s).

Example 1
As shown in FIG. 7, on the surface of the hot melt nonwoven fabric (10) of the cover material A having a surface density of 40 g / m ² to which the hot melt nonwoven fabric prepared in the raw material preparation 2 is adhered, the gas removal particles A obtained in the raw material preparation 1a (3ab) is dispersed so that the surface density is 130 g / m ² . Subsequently, a steam treatment of about 5 Kg / cm ² is performed for about 7 seconds from the cover material (5) side (hot melt nonwoven fabric (10) side), and the hot melt nonwoven fabric (10) is plasticized and melted. The gas removal particles (3ab) were fixed to the web composed of the connecting portion (1) and the resin agglomerated portion (2), via the resin agglomerated portion (2). Subsequently, there were almost no gas removal particles other than the fixed gas removal particles. However, by removing the gas removal particles other than the fixed gas removal particles just in case, the gas removal particles (3ab) become A first layer unit (4) adhered according to the particle size and bonded to the cover material (5) was obtained. Further, the hot-melt nonwoven fabric (10 ″) having a surface density of 20 g / m ² is stacked on the stacked unit (4) in this state, and the gas removal particles A obtained by the raw material preparation 2a so as to have a surface density of 140 g / m ^2. '(3c) The second layer unit (4') was formed through spraying, steam treatment, and removal of gas removal particles that were not fixed for safety.
Next, cover material A (5 ′) having a surface density of 40 g / m ² to which the hot melt nonwoven fabric prepared in raw material preparation 2 is adhered is placed so that the hot melt nonwoven fabric (10 ′) side is in contact with the laminated unit (4 ′). Layered on the laminated unit (4 ′), and subjected to steam treatment at about 5 Kg / cm ² for about 7 seconds from the sheet material (5 ′) side (hot melt nonwoven fabric (10 ′) side), and hot melt nonwoven fabric (10 ') Is plasticized and melted, and activated carbon particles (3c) are formed on the web composed of the connecting portion (1') made of hot melt resin and the resin agglomerated portion (2 ') via the resin agglomerated portion (2'). ) Was fixed to obtain a gas removal filter medium (13) having an areal density of 370 g / m ² and a thickness of 1.0 mm.

  Next, using the obtained gas removing filter medium, as shown in FIG. 8, the filter element (21) has a filter element (21) whose overall size is 225 mm on the shape retaining member side × 235 mm on the side perpendicular to the shape retaining member. In addition, after forming the pleats so that the pleat height H is about 29 mm, the pleat height is about 6 mm, and the number of ridges is 37, hot melt is applied to one side of the frame material (24) made of nonwoven fabric. A frame member (24) bonded with a resin sheet was prepared, and the frame member (24) was fixed in the direction of arrow A shown in FIG. 8 to obtain a filter element. The evaluation results of Example 1 are shown in Table 1.

(Examples 2 and 3 and Reference Example 1 )
In Example 1, the gas removal particles B, C and D prepared in the raw material preparation 1a were used in place of the gas removal particles A, and the gas removal prepared in the raw material preparation 2a instead of the gas removal particles A ′. Filter elements of Examples 2 and 3 and Reference Example 1 were obtained in the same manner as Example 1 except that the particles B ′, C ′ and D ′ were used. Table 1 shows the evaluation results of Examples 2 and 3 and Reference Example 1 .

(Comparative Example 1)
In Example 1, in place of the gas removal particles A, neither potassium carbonate, potassium hydrogen carbonate, phosphoric acid nor 2 - amino-2 -hydroxymethyl- 1,3-propanediol was adhered, particle size 0.25 A filter element of Comparative Example 1 was obtained in the same manner as in Example 1 except that commercially available activated carbon particles classified to ˜0.5 mm were used. The evaluation results of Comparative Example 1 are shown in Table 1.

(Example 5)
As shown in FIG. 7, on the surface of the hot melt nonwoven fabric (10) of the cover material A having a surface density of 40 g / m ² to which the hot melt nonwoven fabric prepared in the raw material preparation 2 is adhered, the gas removal particles E obtained in the raw material preparation 1b (3ab) is dispersed so that the surface density is 140 g / m ² . Subsequently, a steam treatment of about 5 Kg / cm ² is performed for about 7 seconds from the cover material (5) side (hot melt nonwoven fabric (10) side), and the hot melt nonwoven fabric (10) is plasticized and melted. The gas removal particles (3ab) were fixed to the web composed of the connecting portion (1) and the resin agglomerated portion (2), via the resin agglomerated portion (2). Subsequently, there were almost no gas removal particles other than the fixed gas removal particles. However, by removing the gas removal particles other than the fixed gas removal particles just in case, the gas removal particles (3ab) become A first layer unit (4) adhered according to the particle size and bonded to the cover material (5) was obtained. Further, the hot-melt nonwoven fabric (10 ″) having a surface density of 20 g / m ² is stacked on the stacked unit (4) in this state, and the gas removal particles E obtained by the raw material adjustment 2b so as to have a surface density of 180 g / m ^2. '(3c) The second layer unit (4') was formed through spraying, steam treatment, and removal of gas removal particles that were not fixed for safety.
Next, cover material A (5 ′) having a surface density of 40 g / m ² to which the hot melt nonwoven fabric prepared in raw material preparation 2 is adhered is placed so that the hot melt nonwoven fabric (10 ′) side is in contact with the laminated unit (4 ′). Layered on the laminated unit (4 ′), and subjected to steam treatment at about 5 Kg / cm ² for about 7 seconds from the sheet material (5 ′) side (hot melt nonwoven fabric (10 ′) side), and hot melt nonwoven fabric (10 ') Is plasticized and melted, and activated carbon particles (3c) are formed on the web composed of the connecting portion (1') made of hot melt resin and the resin agglomerated portion (2 ') via the resin agglomerated portion (2'). ) Was fixed to obtain a gas removal filter medium (13) having an area density of 420 g / m ² and a thickness of 1.1 mm. The evaluation results of Example 4 are shown in Table 2.

(Example 6)
In Example 1, a filter element of Example 6 was obtained in the same manner as in Example 1 except that instead of the gas removal particle A, the gas removal particle F (3ab) prepared in the raw material preparation 1c was used. The evaluation results of Example 5 are shown in Table 2.

(Example 7)
The dust removal filter medium A obtained in the raw material preparation 3 was laminated on the cover material (5 ′) side of the gas removal filter medium (13) obtained in Example 1. Next, this laminate is passed between a pair of rolls consisting of a heated embossing roll having unevenness and a heating roll having a smooth surface, and is heat-pressed to have a partial fused portion on the surface of the dust removing filter medium A. A composite filter was obtained.
The thickness of this composite filter was 1.3 mm, and the surface density was 390 g / m ² .
Next, using the obtained composite filter, a filter element was obtained in the same manner as in Example 1. The evaluation results of Example 7 are shown in Table 3.

(Examples 8 and 9 and Reference Example 2 )
In Example 7, the same procedure as in Example 7 was used except that the gas removal filter medium obtained in Examples 2 and 3 and Reference Example 1 was used instead of the gas removal filter medium obtained in Example 1. The filter elements of Examples 8 and 9 and Reference Example 2 were obtained. The evaluation results of Examples 8 and 9 and Reference Example 2 are shown in Table 3.

(Comparative Example 2)
In Example 7, the filter element of Comparative Example 2 was used in the same manner as in Example 7 except that the gas removing filter medium obtained in Comparative Example 1 was used instead of the gas removing filter medium obtained in Example 1. Got. The evaluation results of Comparative Example 2 are shown in Table 3.

(Examples 11 and 12)
In Example 7, the gas removal filter medium obtained in Examples 5 and 6 was used in place of the gas removal filter medium obtained in Example 1, and the filter medium of Example 5 had a pleat crest spacing of about 6. Filter elements of Examples 11 and 12 were obtained in the same manner as Example 7 except that 5 mm and 35 peaks were obtained. The evaluation results of Examples 11 and 12 are shown in Table 4.

Table 1

Table 2

Table 3

Table 4

As is apparent from Tables 1 and 3, Examples 1 to 3 obtained from the filter medium for gas removal containing potassium carbonate, phosphoric acid and 2-amino-2 -hydroxymethyl- 1,3-propanediol in the gas removal particles. Comparative Examples 1 and 2 obtained from the filter medium for gas removal which does not contain potassium carbonate, phosphoric acid and 2-amino-2 -hydroxymethyl- 1,3-propanediol in the gas removal particles. The aldehyde gas removal rate is remarkably superior to that of the filter element. In addition to the removal of aldehyde gas, the removal rate of acid gas and alkaline gas is remarkably excellent. Moreover, the filter elements of Examples 1 to 3 and 7 to 9 also retain the effect of removing toluene. Moreover, the filter medium for gas removal of the reference examples 1 and 2 which contains potassium carbonate and 23.5 mass% which exceeded 20 mass% in 2 - amino-2 -hydroxymethyl- 1,3-propanediol in gas removal particle | grains. In this case, although the toluene removal efficiency is slightly lowered, it can be said that the aldehyde gas removal rate is superior to the filter elements of Comparative Examples 1 and 2. Moreover, it can be said that the removal rate of acidic gas and alkaline gas is remarkably excellent. In addition, it was confirmed that the filter elements of Examples 7 to 9 obtained from the composite filter in which the dust removal filter media were laminated had an excellent effect of low pressure loss.

Further, as is apparent from Tables 2 and 4, a gas removal filter medium containing potassium hydrogen carbonate, phosphoric acid and 2-amino-2 -hydroxymethyl- 1,3-propanediol in the gas removal particles, or potassium carbonate, The filter elements of Examples 5, 6, 11 and 12 obtained from a gas removal filter medium comprising potassium hydrogen carbonate, phosphoric acid and 2-amino-2 -hydroxymethyl- 1,3-propanediol in the gas removal particles, The aldehyde gas removal rate is remarkably superior to the filter elements of Comparative Examples 1 and 2 obtained from a gas removal filter medium that does not contain these compounds in the gas removal particles. In addition to the removal of aldehyde gas, the acid gas removal rate is remarkably excellent. In addition, the filter elements of Examples 5, 6, 11, and 12 also retain the toluene removal effect. In addition, it was confirmed that the filter elements of Examples 11 and 12 obtained from the composite filter in which the dust removal filter media were laminated had an excellent effect of low pressure loss.

Further, as is clear from Tables 1 to 4, the filter elements of Examples 2-3 and 5-6 have a significantly higher removal rate of sulfur dioxide gas than the filter elements of Example 1. Although it cannot be said, it was recognized that the removal life of sulfur dioxide gas was remarkably long. Moreover, although the filter element of Examples 7-9, 11-12 does not say that the removal rate of sulfur dioxide gas is remarkably high compared with the filter element of Example 7, about the removal lifetime of sulfur dioxide gas Was found to be significantly longer.

Further, as apparent from Tables 1 to 4, it can be said that the filter elements of Examples 2 to 3 and 5 to 6 have a remarkably high ammonia gas removal rate as compared with the filter element of Example 1. Although it was not, it was recognized that the removal life of ammonia gas was significantly increased. In addition, it cannot be said that the filter elements of Examples 7 to 9, 11 to 12 have a remarkably high ammonia gas removal rate compared to the filter element of Example 7, but the ammonia gas removal life is remarkably high. It was recognized that it was getting longer.

It is a cross-sectional schematic diagram which shows an example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a cross-sectional schematic diagram which shows another example of the filter medium for gas removal of this invention. It is a perspective view which shows an example of the filter element of this invention. In addition, it is a diagram illustrating a mode in which the shape retaining member is mounted in the direction of arrow A. It is a principal part enlarged view of the filter element of this invention. It is a schematic cross section of the filter element of the present invention.

Explanation of symbols

1,1 ', 1 "connecting part (resin body)
2,2 ', 2 "resin agglomerated part (resin body)
3,3 ′ Gas removal particles 3a Gas removal particles (solid particles containing only the compound of general formula (1))
3b Gas removal particles (solid particles containing only acid gas removal agent)
3c Gas removal particles (solid particles containing only alkaline gas removal agent)
3ab gas removal particles (solid particles containing compound of general formula (1) and acid gas removal agent)
4, 4 'Laminate unit 5, 5' Cover material 8 Gas removal particle layer 10, 10 ', 10 "Hot melt resin (hot melt nonwoven fabric) (resin body)
13 Gas removing filter medium 20 Filter element 21 Gas removing filter medium or composite filter 22a Shape retaining member 22b Shape retaining member 23 Fold 24 Separator

Claims (6)

Gas removal that has a gas removal particle layer in which gas removal particles having an average particle diameter of 0.147 to 1.65 mm are connected by a thermoplastic resin and is a sheet-like material having a thickness of 0.2 to 4 mm The gas removal particles include at least acid gas removal particles and alkaline gas removal particles. The acid gas removal particles include potassium carbonate and / or potassium hydrogen carbonate as an acid gas removal agent and 2 -Amino-2 -hydroxymethyl- 1,3-propanediol is admixed after being mixed, and the sum of the mass of the potassium carbonate and the mass of the potassium hydrogen carbonate is the total mass of the acid gas removing particles. a 1 to 3.5 mass% for the mass of the 2-amino-2-hydroxymethyl-1,3-propanediol to the total mass of the acid gas removal particles 2 to 7% by mass, wherein the alkaline gas removing particles have phosphoric acid as an alkaline gas removing agent attached to 1 to 3.5% by mass with respect to the entire alkaline gas removing particles. Filter media.   2. The gas removal filter medium according to claim 1, wherein the gas removal particle layer is formed by laminating at least a layer made of the acid gas removal particles and a layer made of the alkaline gas removal particles.   The gas removal filter medium according to claim 1 or 2, wherein the average particle diameter of the gas removal particles is 0.1 to 1.0 times the thickness of the gas removal filter medium.   A filter element, wherein the gas removal filter medium according to claim 1 is pleated.   A composite filter comprising the gas removing filter medium according to claim 1 and the dust removing filter medium for removing dust.   6. A filter element, wherein the composite filter according to claim 5 is pleated.

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