JP2014036921A - Filter medium for desiccant rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter medium for a desiccant rotor that has high dehumidification efficiency and superior processability of the desiccant rotor.SOLUTION: A filter medium for a desiccant rotor 2 is formed of a porous sheet made containing a moisture absorbent and an organic fiber, the porous sheet containing a non-hygroscopic inorganic filler that is an alumina hydrate or alumina.

Description

  The present invention relates to a filter material for a dehumidifying rotor capable of absorbing and releasing moisture.

  Conventionally, a dehumidifying rotor that can be rotated and continuously heated and regenerated has been proposed. The dehumidifying rotor will be described below. FIG. 1 is a schematic diagram of a typical dehumidifying rotor system. A cylindrical honeycomb structure carrying a hygroscopic agent such as zeolite, activated alumina, silica gel, lithium chloride, or calcium chloride is installed around the core material 1 so that the opening surface of the structure has a cylindrical cross section. Then, the dehumidifying rotor 2 is obtained. The dehumidifying rotor 2 is driven to rotate in the direction of the arrow 3 with the core 1 as the central axis, and the air to be dried 6 containing moisture is cooled by a cooling coil (precooler) 4 and passes through the dehumidifying rotor 2. As a result, moisture is absorbed and removed, and dry air 8 is obtained. On the other hand, the regenerating air 9 for regenerating the dehumidifying rotor 2 is heated to a temperature suitable for regenerating the rotor by the regenerating heater 5 to become heated regenerating air 10, and the heated regenerating air 10 removes moisture from the dehumidifying rotor 2. As a result, the dehumidification rotor 2 is regenerated, and the high-humidity exhaust air 11 containing moisture is obtained. The dry air 8 and the exhaust air 11 thus obtained are supplied to a predetermined space according to the purpose of use.

  The temperature of the high-temperature air that regenerates the dehumidifying rotor is about 80 to 200 ° C., and the dehumidifying rotor is required to have high heat resistance. Moreover, since a heat source is installed in the vicinity, it is necessary to have a high degree of flame retardancy. Therefore, conventionally, an inorganic material having high heat resistance and nonflammability has been used for the dehumidifying rotor. For example, a mixture of molecular sieves, a hygroscopic agent, with kaolin, colloidal silica, and organic resin emulsion added is coated on a carrier such as a wire mesh, metal foil, glass fiber sheet, or asbestos paper, dried, and then impregnated with ethyl silicate. A rotational regeneration type dehumidifier obtained by decomposing and curing, heating at 250 ° C. or higher and burning off the organic resin emulsion has been proposed (for example, see Patent Document 1). In addition, in a continuous dry dehumidifier that involves heating regeneration, an inorganic binder such as colloidal silica, colloidal alumina, colloidal titanium, metal alkoxide, bentonite, and sepiolite is added to and mixed with zeolite as a hygroscopic agent, and the mixture is extruded. There has been proposed a dehumidifying member obtained by forming into a honeycomb shape and then firing at about 800 ° C. (see, for example, Patent Document 2). An inorganic fiber paper made by adding a small amount of pulp and binder to silica-alumina ceramic fibers is formed into a honeycomb shape, and the honeycomb formed body is laminated and bonded in a cylindrical shape at a high temperature. In addition, a honeycomb-like adsorption rotor obtained by immersing a sol obtained by mixing an inorganic sol silica or alumina aqueous sol in a zeolite, which is a hygroscopic agent, after removing the organic matter and drying at a high temperature has also been proposed (for example, patents). Reference 3). In addition, a honeycomb-shaped adsorption rotor is proposed in which activated silica gel or active metal silicate gel that combines moisture adsorption and odor adsorption is formed and bonded to a honeycomb molded body made of inorganic fiber paper mainly composed of ceramic fibers. (For example, see Patent Document 4).

  The above dehumidifying rotor is a non-combustible member having a high degree of heat resistance made of only an inorganic material, and effectively functions as a dehumidifying rotor that is rotationally driven and continuously heated and regenerated. However, when considering the application of a dehumidification rotor to home appliances, home use, etc., depending on the use (eg, dehumidification of the interior of a building or room), regeneration at a high temperature is not necessarily required, or the heat resistance of the product housing From the viewpoint of safety, energy saving and safety, there are various circumstances such as difficulty in adopting a regeneration system at a high temperature, and heat resistance and nonflammability as that of an inorganic dehumidification rotor are not essential elements. Rather, because pottery is hard and brittle, it is extremely weak and fragile to impact, and high-temperature heat treatment such as baking is performed to remove or reduce the organic components, so the adsorption characteristics of the hygroscopic agent may be deteriorated and the material selection There is a limitation, the fixing strength of the hygroscopic agent is insufficient only with inorganic materials, a certain amount of powder falling is unavoidable, it is difficult to control the thickness of the base material constituting the dehumidification rotor and the thin layer, and control the pressure loss of the dehumidification rotor And because it is a ceramic manufacturing method that makes it difficult to reduce pressure loss, volume change is likely to occur in the dehumidification rotor during high-temperature heat treatment such as firing, resulting in reduced yield due to poor dimensional accuracy, cracks, etc. Various drawbacks of inorganic dehumidification rotors, such as expensive members, have been seen as close-ups and problems, and there has been an increasing demand for these improvements.

  Further, in the desiccant air conditioning system, the dehumidification rotor rotates at a low speed of 10 to 30 rph, but the air in the moisture absorption zone and the regeneration zone mixes with each other around the dotted line A that is the interface between the adsorption zone and the regeneration zone. Therefore, heated air 10 enters the adsorption zone and inhibits dehumidification, dehumidified air 8 enters the regeneration zone and lowers the temperature of heated air 10, and air containing moisture desorbed from dehumidification rotor 2. 11 enters the adsorption zone, raising the humidity and temperature of the moist outside air 7, resulting in a problem that the dehumidifying performance is lowered. Since the inorganic dehumidification rotor has a dense structure, this air mixing is difficult to occur. However, in the organic dehumidification element having a large gap and a sparse structure, the dehumidification performance is deteriorated due to the air mixing.

  In order to solve these problems, we are studying humidity control sheets in which a porous sheet and a non-porous sheet are laminated. When a non-porous sheet is laminated on one side of a porous sheet, the porous sheet The dehumidifying performance on one side is remarkably reduced, and when sandwiched with a porous sheet around a non-porous sheet, the thickness increases, so there is a disadvantage that pressure loss increases when processed into a rotor (for example, , See Patent Document 5).

  In addition, attempts to make a porous adsorbent film by kneading an adsorbent with a thermoplastic resin have been made conventionally (see, for example, Patent Documents 6 to 8). However, in a film in which an adsorbent is kneaded into a thermoplastic resin in this way, the adsorbent is covered with a thin film layer made of a thermoplastic resin, thereby preventing contact with moisture and other adsorbents, and adsorbing There was a problem that the original adsorption performance of the agent could not be fully exhibited.

JP 54-19548 A JP-A 63-240921 JP-A-6-226037 Japanese Patent Laid-Open No. 5-115737 JP 2010-184184 A Special table 2004-526569 gazette JP 2006-116501 A JP 2006-346888 A

  An object of the present invention is to provide a filter material for a dehumidification rotor having high dehumidification efficiency, excellent honeycomb processability, and appropriate pressure loss.

The present invention
(1) A filter material for a dehumidification rotor comprising a porous sheet comprising a hygroscopic agent and an organic fiber, wherein the porous sheet contains a non-hygroscopic inorganic filler,
(2) The dehumidifying rotor filter medium according to (1), wherein the non-hygroscopic inorganic filler is alumina hydrate,
(3) The filter material for a dehumidification rotor according to (1) or (2), wherein the porous sheet contains 5 to 40% by mass of a non-hygroscopic inorganic filler,
(4) The filter medium for a dehumidification rotor according to any one of (1) to (3), wherein the non-hygroscopic inorganic filler has an average particle size of 1.0 to 100.0 μm,
(5) The filter medium for a dehumidification rotor according to any one of (1) to (4), wherein the air permeability resistance is 100 sec / 100 ml or more.
It is.

  The dehumidifying rotor filter medium of the present invention is a dehumidifying rotor filter medium comprising a porous sheet containing a hygroscopic agent and organic fibers, and the porous sheet contains a non-hygroscopic inorganic filler, thereby removing the dehumidifying rotor. The heat capacity of the filter medium can be reduced, the air resistance can be increased, and surprisingly, the dehumidification performance can be remarkably improved. Further, the filter medium for a dehumidifying rotor carrying a moisture absorbent has good dimensional stability and good rigidity, so that the honeycomb processability is also excellent.

  Also, by using alumina hydrate or alumina as the non-hygroscopic filler, the compatibility with the hygroscopic agent and the organic fiber is good, so the dispersibility of the dispersion carried on the sheet is improved, and coating (impregnation) is performed. Improves the surface properties and improves the dehumidifying performance.

  In addition, the non-hygroscopic filler is preferably contained in an amount of 5 to 40% by mass of the filter material for the dehumidifying rotor, and if it is within this range, the effect of being excellent in dehumidifying amount and appropriate pressure loss can be obtained.

  Furthermore, the average particle diameter of the non-hygroscopic filler is preferably 1.0 to 100.0 μm, and when it is within this range, streaky streaks are not generated on the surface of the filter medium for the dehumidifying rotor during coating (impregnation). The surface property is improved and the dehumidifying performance is improved.

  Furthermore, the air permeability resistance of the filter medium for the dehumidification rotor is preferably 100 sec / 100 ml or more, air leakage from the filter medium surface can be eliminated, the pressure loss can be reduced, and the dehumidification performance can be improved.

It is a schematic diagram which shows a typical dehumidification rotor system.

  Hereinafter, components related to the filter medium for a dehumidification rotor of the present invention (hereinafter, may be abbreviated as “filter medium”) will be described in detail.

  The filter material for a dehumidifying rotor of the present invention is composed of a porous sheet containing a hygroscopic agent, organic fibers, and a non-hygroscopic inorganic filler.

  As the hygroscopic agent, a super absorbent polymer, an organic hygroscopic agent such as carboxymethylcellulose, sepiolite, zeolite, bentonite, attapulgite, diatomaceous earth, diatomaceous earth shale, activated carbon, porous silica, aluminum hydroxide, fibrous titanium oxide, allophane, Inorganic moisture absorbents such as imogolite and amorphous aluminosilicate can be used. The content of the hygroscopic agent in the filter medium for the dehumidifying rotor is preferably 30 to 80% by mass, more preferably 40 to 75% by mass, and 50 to 70% by mass with respect to the porous sheet. Further preferred. If it is less than 30% by mass, the desired dehumidification efficiency may not be obtained. If it exceeds 80% by mass, it becomes extremely difficult to support the filter medium for the dehumidification rotor, and the control of the thickness becomes difficult. In some cases, workability may be reduced.

  Organic fibers include olefin resins, polyester resins, polyvinyl acetate resins, ethylene vinyl acetate copolymer resins, polyamide resins, acrylic resins, polyvinyl chloride resins, polyvinylidene chloride resins, polyvinyl ether resins, polyvinyl ketone resins, Thermosetting resins such as polyether resins, polyvinyl alcohol resins, diene resins, and polyurethane resins, phenol resins, melamine resins, furan resins, urea resins, aniline resins, unsaturated polyester resins, alkyd resins, etc. It is a fiber made of resin. In addition, plant fibers such as wood pulp, cocoon, cocoon, cocoon, kenaf, bamboo, linter, bagasse, esparto, sugarcane, etc., or refined ones of these can be used. Semi-synthetic fibers such as acetate, fluororesin fibers such as polytetrafluoroethylene (PTFE), silicone resin fibers, and the like can also be used. In the present invention, metal fibers such as stainless steel and nickel wool, carbon fibers, ceramic fibers, glass fibers, and the like can be used as long as the processability during the production of the filter medium for the dehumidifying rotor is not lost.

  Non-hygroscopic inorganic filler is a definition of inorganic filler that has very little moisture absorption, such as adsorption capacity, hygroscopicity, and moisture absorption speed, compared to inorganic fillers used as ordinary hygroscopic agents. In terms of desiccant quality (JIS Z 0701) The corresponding moisture absorption (%) was 1.5 or less at 20% relative humidity, 5 or less at 50% relative humidity, and 25 or less at 90% relative humidity.

(Expression 1) Moisture absorption rate (%) = (W1-W0) / W0 × 100
* W1 = weight of sample absorbed (g), W0 = dry weight of sample (g)

  Non-hygroscopic inorganic fillers include oxide fillers such as alumina, silica (silicon oxide), titania, zirconia, magnesia, zinc oxide and iron oxide, nitride ceramics such as silicon nitride, titanium nitride and boron nitride, Silicon carbide, calcium carbonate, aluminum sulfate, barium sulfate, potassium titanate, talc, kaolin clay, kaolinite, halloysite, pyrophyllite, montmorillonite, sericite, mica, amicite, bentonite, asbestos, calcium silicate, silicic acid Examples thereof include ceramics such as magnesium and silica sand, and glass particles. These can be used alone or in combination of two or more. Among these, it is preferable to use alumina hydrate or alumina from the viewpoint of improving the dehumidifying performance.

  The content of the non-hygroscopic inorganic filler is preferably 5 to 40% by mass, more preferably 10 to 30% by mass, and further preferably 15 to 25% by mass with respect to the porous sheet. preferable. When the amount is less than 5% by mass, it is difficult to obtain the effect of the present invention that lowers the heat capacity of the filter medium for the dehumidifying rotor, increases the air resistance, and remarkably improves the dehumidifying performance. Moreover, since the dimensional stability of the dehumidification rotor filter medium carrying the moisture absorbent is good and good rigidity is obtained, it is difficult to obtain the effect of excellent honeycomb processability. If it exceeds 40% by mass, the dehumidification amount may decrease and the pressure loss may deteriorate.

  The average particle size of the non-hygroscopic inorganic filler is preferably 1.0 to 100.0 μm, more preferably 1.5 to 50.0 μm, and further preferably 2.0 to 10.0 μm. . When the average particle size is less than 1.0 μm, there may be a problem that the fibers fall off from the fibers constituting the porous sheet. When the average particle size exceeds 100.0 μm, streaky streaks may occur on the surface of the dehumidification rotor filter medium during coating (impregnation). The average particle diameter in the present invention refers to the “arithmetic average value of particle diameter” defined in JIS Z 8901: 2006 “Test Powder and Test Particles”.

  As a method for producing a porous sheet, a method for producing a porous sheet containing a hygroscopic agent, organic fibers and a non-hygroscopic inorganic filler by a papermaking method or a dry method, paper, dry nonwoven fabric, wet nonwoven fabric, woven fabric, It contains a hygroscopic agent and organic fibers prepared by a paper making method or a dry method, by applying (impregnating) a hygroscopic agent and a non-hygroscopic inorganic filler to a base material containing organic fibers such as fabrics. Applying (impregnating) a non-hygroscopic inorganic filler to a base material to be formed, coating a hygroscopic agent on a base material containing organic fibers and non-hygroscopic inorganic filler prepared by a papermaking method or a dry method Examples of the method include (impregnation) and inclusion. A plurality of methods may be combined.

  In the method of containing a hygroscopic agent or a non-hygroscopic inorganic filler by coating (impregnation), a solution or dispersion containing a hygroscopic agent or a non-hygroscopic inorganic filler is used as the coating liquid. As the medium, water or a mixed solution of water and an organic solvent such as alcohol or ketone can be preferably used. For coating methods, various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, short dwell coaters, die coaters, comma coaters, reverse roll coaters, kiss coaters, dip coaters, curtain coaters, extrusion coaters, micro gravure coaters The method of coating on a porous base material using various coating apparatuses, such as, can be mentioned. In the impregnation method, an impregnation apparatus such as a size press can be used.

  The hygroscopic agent and the non-hygroscopic inorganic filler can be contained in the porous sheet using a binder. As the binder, acrylic resin, styrene-acrylic copolymer, styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate-vinyl chloride copolymer, Polypropylene, polyester, phenoxy resin, phenol resin, butyral resin, and the like can be used. Among these, the use of an acrylic resin binder is more preferable because it increases the hardness of the filter medium, improves the honeycomb processability, and prevents the hygroscopic agent and the non-hygroscopic inorganic filler from falling off.

  In the present invention, it is more preferable to subject the porous sheet obtained by the above-described method to a thermal calendar treatment. By this treatment, it becomes possible to increase the sheet strength while maintaining a high content ratio of the hygroscopic agent, and to obtain a filter material for a dehumidification rotor with high dehumidification efficiency and low pressure loss without impairing honeycomb processability. be able to.

  Thermal calendering is composed of a combination of rolls such as a metal roll and a metal roll, a metal roll and a resin roll, a metal roll and an elastic roll, and the nonwoven fabric is passed through a nip portion where at least one roll is heated. The thickness, hardness, and smoothness of the nonwoven fabric after the treatment can be controlled by the heating temperature of the roll and the nip pressure. In the present invention, although it depends on the type of the nonwoven fabric and the hygroscopic agent, it is usually preferable to perform the treatment at a heating temperature of 60 to 150 ° C. and a nip pressure of 0.5 to 5 MPa.

  In the present invention, the air resistance of the dehumidification rotor filter medium is preferably 100 sec / 100 ml or more. In the case of 100 sec / 100 ml or more, air leakage from the filter medium surface can be eliminated, pressure loss can be reduced, and dehumidification performance can be improved.

In the present invention, the basis weight of the dehumidification rotor filter medium is preferably 50 to 300 g / m ² and the thickness is preferably 50 to 300 μm. More preferably, they are 100-250 g / m < ² >, 100-250 micrometers, More preferably, they are 150-200 g / m < ² >, 150-200 micrometers. If the basis weight and thickness are reduced outside this range, the intended moisture absorption efficiency may not be obtained, and the honeycomb processability may be reduced. Conversely, when the basis weight and thickness are high, although dehumidification performance is obtained, problems such as increased pressure loss may occur.

  Next, the rotor processing of the filter medium for the dehumidifying rotor of the present invention will be described below. The filter medium for a dehumidification rotor of the present invention can be processed into a honeycomb and formed into a honeycomb structure and used as a dehumidification rotor. The honeycomb structure according to the present invention is a structure composed of cell walls having pores, and as a specific example, a single-sided structure manufactured in accordance with “Exterior Corrugated Cardboard” described in JIS-Z1516-1995. Corrugated honeycomb structure composed of corrugated cardboard, hexagon honeycomb structure composed of hexagonal cells, honeycomb structure composed of square cells, honeycomb structure composed of triangular cells, and honeycomb structure formed by assembling hollow cylindrical cells Examples include structures. Here, the cell shape such as a hexagon or a square is not necessarily a regular polygon, and may be an irregular shape such as a rounded corner or a bent side.

  Further, a method of manufacturing a honeycomb structure formed using the filter material for a dehumidifying rotor of the present invention by cutting it into a disk shape by a method such as die cutting, and swirling a single-sided cardboard formed using the filter material for a dehumidifying rotor of the present invention The method etc. which make it into a shape are mentioned.

  The honeycomb structure not only has a high open area ratio and excellent air permeability, but also has a large surface area, and therefore effectively functions as a dehumidifying rotor having a large capacity of adsorption performance. In addition, conventional inorganic dehumidification rotors are earthenware-like, hard and brittle, so they are extremely weak and fragile to impact, and high-temperature heat treatment such as firing is performed to remove or reduce organic components. There is a risk of deterioration and restrictions on material selection. With inorganic materials alone, the fixing strength of the hygroscopic agent is insufficient, and a certain amount of powder falling is unavoidable.Thickness control and thinning of the substrate constituting the dehumidification rotor are possible. It is difficult to control the pressure loss of the dehumidification rotor and it is difficult to reduce the pressure loss, so that the volume of the dehumidification rotor easily changes during high-temperature heat treatment such as firing, resulting in poor dimensional accuracy. There was a series of problems such as high cost due to yield reduction due to cracks, etc., but the honeycomb structure formed using the filter material for the dehumidification rotor of the present invention solved these problems. Rukoto is possible.

  Hereinafter, the present invention will be described in detail with reference to examples. However, the present invention is not limited to the examples without departing from the gist of the present invention.

[Preparation of Substrate 1]
As organic fibers, 100 parts by mass of polyester fiber (fineness 0.55 dtex, fiber length 5 mm) and 60 parts by mass of core-sheath type heat-fusible polyester fiber (fineness 2.2 dtex, fiber length 5 mm) are added and mixed in water. An aqueous dispersion of 0.3% by weight fiber was prepared. Next, appropriate amounts of polyaluminum chloride and cationic polyacrylamide were added as a flocculant to prepare a 0.3% by mass aqueous dispersion for preparing a nonwoven fabric.

Using a circular paper machine, a web having a basis weight of 40 g / m ² and a thickness of 0.1 mm is wet-made from the produced aqueous dispersion, and subjected to pressure and heat treatment with a cylinder dryer, whereby the substrate 1 which is a wet nonwoven fabric is obtained. Produced.

[Preparation of Substrate 2]
Polyester fiber (fineness 2.2 decitex, fiber length 50 mm) / polyester fiber (fineness 4.4 decitex, fiber length 50 mm) = 80/20 mass ratio is defibrated and mixed to produce a 28 g / m ² web. The web was impregnated with an acrylic resin emulsion in terms of an active ingredient at 12 g / m ² and dried to give strength, thereby preparing a substrate 2 which was a dry nonwoven fabric having a basis weight of 40 g / m ² and a thickness of 0.3 mm.

Example 1
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), an aqueous slurry (coating solution) containing 20 parts by mass of alumina hydrate (trade name: C20, manufactured by Daimei Chemical Industry Co., Ltd., average particle size 2.3 μm) which is a non-hygroscopic inorganic filler. Prepared and coated on the substrate 1 with a blade coater so that the dry coating amount is 60 g / m ² on one side, and subjected to thermal calendering (temperature: 110 ° C., nip pressure: 5 MPa). A filter medium for a dehumidifying rotor of Example 1 having an amount of 160 g / m ² and a thickness of 160 μm was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 2
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 84 parts by mass, binder (acrylic resin emulsion) 10 parts by mass (solid) Min), an aqueous slurry (coating solution) containing 6 parts by mass of alumina hydrate (trade name: C20, manufactured by Daimei Chemical Industry Co., Ltd., average particle size 2.3 μm) which is a non-hygroscopic inorganic filler. A double-sided coating is applied to the substrate 1 with a blade coater so that the dry coating amount is 60 g / m ² on one side, and a thermal calendar treatment (temperature: 110 ° C., nip pressure: 5 MPa) is applied. A filter medium for a dehumidifying rotor of Example 2 having an amount of 160 g / m ² and a thickness of 160 μm was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 3
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 40 parts by mass of binder (acrylic resin emulsion) (solid) Minute), 50 parts by mass of alumina hydrate (trade name: C20, manufactured by Daimei Chemical Co., Ltd., average particle size 2.3 μm), and an aqueous slurry (coating solution) is prepared. A dry press coating amount is 160 g / m ² with a size press, heat calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 200 g / m ² and thickness 200 μm is applied. The filter material for a dehumidification rotor of Example 3 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 4
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), alumina hydrate (trade name: C06, manufactured by Daimei Chemical Co., Ltd., average particle size 0.7 μm), 16 parts by mass, alumina hydrate (trade name: C20, manufactured by Daimei Chemical Co., Ltd.) Prepare an aqueous slurry (coating solution) containing 4 parts by weight of an average particle size of 2.3 μm and apply double-sided coating on the base material 1 with a blade coater so that the dry coating amount is 60 g / m ² on one side. Then, a heat calender treatment (temperature: 110 ° C., nip pressure: 5 MPa) was performed to obtain a filter material for a dehumidification rotor of Example 4 having a basis weight of 160 g / m ² and a thickness of 160 μm.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 5
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), alumina (polishing fine powder A (molten alumina) # 3000, Technorise Co., Ltd., average particle size 5.0 μm) 20 parts by mass, an aqueous slurry (coating liquid) is prepared, No. ² was coated with a size press so that the dry coating amount was 120 g / m ^{2, and} was subjected to thermal calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 160 g / m ² , thickness 200 μm. The filter material for dehumidification rotors of Example 5 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 6
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), alumina (polishing fine powder A (molten alumina) # 1500, manufactured by Technorise Co., Ltd., average particle size 10.0 μm), 20 parts by mass, and an aqueous slurry (coating liquid) is prepared. No. ² was coated with a size press so that the dry coating amount was 120 g / m ^{2, and} was subjected to thermal calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 160 g / m ² , thickness 200 μm. The filter material for dehumidification rotors of Example 6 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 7
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), titanium oxide (trade name: Taipei (registered trademark), manufactured by Ishihara Sangyo Co., Ltd., average particle size: 1.0 μm), 20 parts by weight, and an aqueous slurry (coating solution) is prepared. 1 was coated on both sides with a blade coater so that the dry coating amount was 60 g / m ² on one side, and was subjected to thermal calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 160 g / m ² , A filter medium for a dehumidifying rotor of Example 7 having a thickness of 160 μm was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 8
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Minute) and 20 parts by mass of glass particles (average particle size 100 μm), and an aqueous slurry (coating solution) is prepared so that the dry coating amount is 120 g / m ² on the substrate 2 by a size press. And a heat calender treatment (temperature: 110 ° C., nip pressure: 5 MPa) was performed to obtain a filter material for a dehumidification rotor of Example 8 having a basis weight of 160 g / m ² and a thickness of 200 μm.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Comparative Example 1
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 90 parts by mass, binder (acrylic resin emulsion) 10 parts by mass, An aqueous slurry (coating solution) is prepared and coated on the substrate 1 with a blade coater so that the dry coating amount is 55 g / m ² on one side, and a thermal calendar treatment (temperature: 110 ° C.). , Nip pressure: 5 MPa) to obtain a filter material for a dehumidifying rotor of Comparative Example 1 having a basis weight of 150 g / m ² and a thickness of 200 μm.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Comparative Example 2
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 90 parts by mass of binder (acrylic resin emulsion) (solid) The aqueous slurry (coating solution) containing the component is prepared, and applied to the substrate 2 with a size press so that the dry coating amount becomes 110 g / m ² , and the thermal calendar treatment (temperature: 110). The filter medium for a dehumidification rotor of Comparative Example 2 having a basis weight of 150 g / m ² and a thickness of 200 μm was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 9
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore size 3 nm, specific surface area 820 m ² / g), 85 parts by mass, binder (acrylic resin emulsion) 10 parts by mass (solid) Min), an aqueous slurry (coating solution) containing 5 parts by mass of alumina hydrate (trade name: C20, manufactured by Daimei Chemical Industry Co., Ltd., average particle size 2.3 μm) Double-side coating is performed with a blade coater so that the dry coating amount is 60 g / m ² on one side, heat calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 160 g / m ² , thickness 160 μm. The filter material for dehumidification rotors of Example 9 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 10
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 30 parts by mass, binder (acrylic resin emulsion) 10 parts by mass (solid) Minute), 60 parts by mass of alumina hydrate (trade name: C20, manufactured by Daimei Chemical Co., Ltd., average particle size 2.3 μm), and preparing an aqueous slurry (coating liquid). Are coated with a blade coater so that the coating amount is 60 g / m ² on one side, and subjected to thermal calendering (temperature: 110 ° C., nip pressure: 5 MPa), basis weight 160 g / m ² , thickness 160 μm. The filter material for dehumidification rotors of Example 10 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

Example 11
[Preparation of filter material for dehumidification rotor]
Hygroscopic agent (trade name: Mizuka Soap (registered trademark) S-0, manufactured by Mizusawa Chemical Industry Co., Ltd., average pore diameter 3 nm, specific surface area 820 m ² / g), 70 parts by mass of binder (acrylic resin emulsion) (solid) Min), alumina (trade name: Polished fine powder KOA, manufactured by Technorise Co., Ltd., average particle size 110.0 μm), and an aqueous slurry (coating liquid) is prepared. Applying on both sides so that the coating amount is 70 g / m ² on one side with a coater, applying a heat calendering process (temperature: 110 ° C., nip pressure: 5 MPa), and carrying out a basis weight of 160 g / m ² and a thickness of 160 μm The filter material for the dehumidification rotor of Example 11 was obtained.

[Production of dehumidification rotor]
A single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm is produced from the produced filter medium for a dehumidifying rotor by a corrugating machine, and this is wound up into a spiral shape, and a cylindrical rotor having an inner diameter of 90 mm, an outer diameter of 350 mm, and a thickness of 200 mm A shaped dehumidifying rotor was produced.

[Air permeability resistance of filter media]
The air permeation resistance is an index indicating the degree of air escape from the surface of the sheet. If the air easily escapes from the sheet surface, leaks are likely to occur when the sheet is corrugated to form a rotor, and the air in the moisture absorption zone and the regeneration zone is mixed. Therefore, heated air enters the adsorption zone and inhibits dehumidification, dehumidified air enters the regeneration zone and lowers the temperature of the heated air, and air containing moisture desorbed from the dehumidification rotor enters the adsorption zone. The problem arises that the humidity and temperature of the wet outside air are increased and the dehumidifying performance is lowered. The evaluation was performed by the Oken type tester method according to the JIS P8117 paper and paperboard-air permeability and air resistance resistance test method using the filter media for the dehumidification rotor of Examples and Comparative Examples.

  In Examples 1 to 8 and 10, the air resistance was 100 sec / 100 ml or more. Comparative Examples 1-2 and Examples 9 and 11 had low air resistance.

  As mentioned above, the filter material for a dehumidification rotor and the dehumidification rotor of an Example and a comparative example were evaluated according to the following performance test. The results are shown in Table 2.

[Evaluation method and evaluation of specific heat capacity of filter medium]
Specific heat capacity is the amount of heat required to raise the unit temperature of a substance under conditions of constant pressure or volume. If the specific heat capacity is high, the substance is hard to warm, and if the specific heat capacity is low, the substance is easy to warm. Evaluation was performed according to the specific heat capacity measuring method of JIS K7123-1987 plastic.

  However, since the filter medium contained a hygroscopic agent, it was determined that the filter medium was easily affected by moisture. Therefore, the measurement was performed after the filter medium was left in a dryer preheated to 90 ° C. for 2 hours.

  Examples 1-8, 10 and 11 had a low specific heat capacity. In Comparative Examples 1-2 and Example 9, the specific heat capacity was high because the amount of the non-hygroscopic inorganic filler added was as small as 0 to 4% by mass.

[Evaluation method and evaluation of corrugating workability]
Using the filter material for the dehumidification rotor of the examples and comparative examples, a corrugated machine was used to produce a single-sided cardboard having a height of 1.9 mm and a pitch of 3.2 mm, and the resulting corrugated shapes were classified into four stages and evaluated. went.

◎: Corrugated honeycomb structure is firm and hard and does not collapse at all ○: Corrugated honeycomb structure is firm Δ: Corrugated honeycomb structure collapses when force is applied ×: Corrugated honeycomb structure Could not be molded

  In each of the filter media of Examples 1 to 9 and Comparative Examples 1 and 2, the corrugated honeycomb structure was firm. In the filter medium of Example 10, although the corrugated honeycomb-like structure was firm, the amount of the non-hygroscopic inorganic filler was large, so the thickness of the filter medium was too thick and the corrugate workability was slightly inferior. Furthermore, since the filter medium of Example 11 used a non-hygroscopic inorganic filler having a large particle size, the smoothness of the filter medium surface was lost, and the corrugated honeycomb structure was crushed.

[Evaluation method and evaluation of dehumidification amount]
The dehumidification rotor produced by the Example and the comparative example evaluated the dehumidification amount on condition of the following using the dehumidification rotor system of FIG. The evaluation condition is that the rotational speed of the dehumidifying rotor 2 is 30 rph, and the indoor air (dried air 6 containing moisture) is cooled by a cooling coil (precooler) 4 so that the surface wind speed is 2 m / sec. (25 ° C., mass absolute humidity 16 g / kg (DA)). The temperature and humidity at the dehumidification side outlet of the dry air 8 coming out from the dehumidification rotor 2 was measured, and the dehumidification amount (C) was determined from the difference between the dehumidification inlet mass absolute humidity (A) and the dehumidification outlet mass absolute humidity (B). (Formula 2 below).

(Formula 2)
Dehumidification amount (C) g / kg (DA) = Dehumidification inlet mass absolute humidity (A) -Dehumidification outlet mass absolute humidity (B)

◎: Dehumidification amount is 12 g / kg (DA) or more ○: Dehumidification amount is 9 g / kg (DA) or more and less than 12 g / kg (DA) Δ: Dehumidification amount is 6 g / kg (DA) or more, 9 g / kg (DA Less than x): Dehumidification amount is less than 6 g / kg (DA)

  The dehumidification rotor produced in Examples 1-11 showed favorable dehumidification amount. In comparison between Examples 1 to 4 and 9 to 10, the dehumidification performance of the dehumidification rotors of Examples 1 to 4 in which the content of the non-hygroscopic inorganic filler is 5 to 40% by mass with respect to the porous sheet is excellent. Among them, the dehumidification rotors of Example 1 and Example 4 have a good balance of the content ratio of the hygroscopic agent and the non-hygroscopic inorganic filler, and the non-hygroscopic inorganic filler is filled between the fibers of the porous sheet. Good results were shown. On the other hand, since the dehumidification rotors of Comparative Examples 1 and 2 did not contain a non-hygroscopic inorganic filler, a good dehumidification amount could not be obtained. Even when a non-hygroscopic inorganic filler having no hygroscopic property was added, when the filter medium for a dehumidifying rotor of the present invention was used, a surprising result was obtained that the dehumidifying performance was improved. From the comparison of Examples 1 and 4 to 8, it was shown that when the non-hygroscopic inorganic filler is alumina hydrate or alumina, the dehumidifying performance is excellent. In Examples 9 and 11 in which the air permeability resistance was less than 100 sec / 100 ml, it was shown that the dehumidifying performance slightly decreased.

  The filter material for a dehumidification rotor of the present invention can be used for a desiccant air conditioning system. Further, it can be used for dehumidification and transpiration of refrigerators, freezers, refrigerated showcases, frozen showcases, etc., dehumidification, humidification, heat exchange elements, etc. of electrical products.

1 Core material 2 Dehumidification rotor 3 Rotation direction of dehumidification rotor 4 Cooling coil (precooler)
5 Regenerative heater 6 Dried air containing moisture 7 Dried air 8 containing cooled moisture 8 Drying air 9 Regenerating air 10 Heated regenerating air 11 Exhaust air

Claims (5)

  A filter material for a dehumidification rotor comprising a porous sheet comprising a hygroscopic agent and an organic fiber, wherein the porous sheet contains a non-hygroscopic inorganic filler.   The filter material for a dehumidification rotor according to claim 1, wherein the non-hygroscopic inorganic filler is alumina hydrate or alumina.   The filter medium for a dehumidification rotor according to claim 1 or 2, wherein the porous sheet contains 5 to 40% by mass of a non-hygroscopic inorganic filler.   The filter medium for a dehumidification rotor according to any one of claims 1 to 3, wherein the non-hygroscopic inorganic filler has an average particle diameter of 1.0 to 100 µm.   The filter medium for a dehumidification rotor according to any one of claims 1 to 4, wherein the air permeability resistance is 100 sec / 100 ml or more.

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