Spacer sheet and total heat exchange element

Abstract

To provide a spacing member and a total heat exchanger wherein the generation of condensation water is prevented.SOLUTION: The present invention discloses sheets for spacing members of a total heat exchanger, wherein the total heat exchanger has a plurality of partition members, and spacing members that form an air passage between the plurality of partition members and hold the space between the partition members. The sheets for spacing members include cellulose fiber as the main component and further include a moisture absorbent and a surfactant.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a spacing member sheet and a total heat exchange element. [Background technology]

[0002] Conventionally, heat exchangers have been known as devices for ventilating without impairing the effectiveness of cooling or heating. In heat exchangers, heat is exchanged between two types of airflow, intake air and exhaust air, during ventilation. Total heat exchange elements are widely used for heat exchangers. Total heat exchange elements have a structure in which sheet-like partition members are alternately bonded together with corrugated spacing members interposed therebetween. The corrugated spacing members form air flow paths between the partition members, thereby separating an intake air path that introduces outdoor air into the room from an exhaust air path that discharges indoor air to the outside.

[0003] These spacing members are required to have high moisture absorption properties in order to exchange sensible heat (temperature) and latent heat (humidity) at the same time while blocking the ventilation of the air intake and exhaust paths. For this reason, spacing members made of paper substrates with moisture absorbents are used. When moisture absorbents are held in spacing members, they can easily absorb moisture inside, allowing for smooth movement of water vapor and efficient exchange of latent heat (humidity).

[0004] For example, Patent Documents 1 and 2 disclose total heat exchange elements having partition members and spacing members each having a water-soluble moisture absorbent. Patent Document 1 discloses a technique of adding a water-soluble moisture absorbent to the spacing members as well in order to prevent the water-soluble moisture absorbent contained in the partition members from being washed away. Patent Document 2 uses spacing members that have water-retentive properties and are impregnated with a water-absorbent resin. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2008 / 041327 [Patent Document 2] International Publication No. 2009 / 004695 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the total heat exchange elements of the prior art, there was a problem that condensation water was generated on the spacing members, etc. depending on the usage environment. The generation of such condensation water causes serious problems such as tracking in devices having the total heat exchange elements, and therefore improvement was required.

[0007] Therefore, in order to solve the problems of the conventional technology, the present inventors have carried out studies with the aim of providing a spacing member and a total heat exchange element in which the generation of condensation water is suppressed. [Means for solving the problem]

[0008] As a result of intensive research to solve the above problems, the inventors discovered that by adding a moisture absorbent and a surfactant to a spacing member sheet containing cellulose fiber as the main component, a spacing member sheet in which the generation of condensation water is suppressed can be obtained. Specifically, the present invention has the following configuration.

[0009] [1] A spacing member sheet for a total heat exchange element, which is used in a total heat exchange element having a plurality of partition members and a plurality of spacing members that form air flow paths between the plurality of partition members and maintain the spacing between the partition members, It contains cellulose fiber as its main component, A spacing member sheet further comprising a moisture absorbent and a surfactant. [2] Cobb absorbency: 30-100g / m 2 The spacing member sheet according to [1], [3] The spacing member sheet according to [1] or [2], wherein the moisture absorbent is at least one selected from the group consisting of calcium chloride and lithium chloride. [4] The moisture absorbent content is per 1 m of spacing sheet. 2The spacing member sheet according to any one of [1] to [3], which weighs 2 to 30 g per sheet. [5] The spacing member sheet according to any one of [1] to [4], wherein the surfactant is a nonionic surfactant. [6] A spacing member sheet according to any one of [1] to [5], A sheet containing cellulose fiber as its main component, A method for manufacturing a spacing member sheet, which comprises applying or impregnating a sheet with a solution containing a moisture absorbent and a surfactant. [7] A total heat exchange element comprising a plurality of spacing members made of the spacing member sheet according to any one of [1] to [5] and a plurality of partition members, The spacing member forms an air flow path between the plurality of partition members and maintains the spacing between the partition members. This is a total heat exchange element. [Effects of the Invention]

[0010] According to the present invention, it is possible to obtain a spacing member sheet in which the generation of condensation water is suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram illustrating the structure of a total heat exchange element. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments or specific examples, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0013] (total heat exchange element) The present invention relates to a total heat exchange element including a plurality of partition members and a plurality of spacing members that form air flow paths between the partition members and maintain the spacing between the partition members. Here, the spacing members contain cellulose fiber as a main component and further contain a moisture absorbent and a surfactant. Because the total heat exchange element of the present invention has the above configuration, the generation of condensation water inside is suppressed.

[0014] Fig. 1 is a schematic diagram illustrating the structure of a total heat exchange element 10 according to this embodiment. As shown in Fig. 1, the total heat exchange element 10 is composed of a plurality of partition members 1 and a plurality of spacing members 2 that form air flow paths between the plurality of partition members 1 and maintain the spacing between the partition members 1. The partition members 1 are flat plates with a square, diamond, or other shape, and the spacing members 2 are corrugated plates formed with a waveform such as a sawtooth wave or a sine wave whose projected planar shape matches the shape of the partition members 1. The spacing members 2 are shaped, for example, like the core of cardboard and are formed by corrugating.

[0015] The ridges and valleys of the wave-shaped spacing member 2 are joined to the partition member 1 with an adhesive or the like. The spacing member 2 is joined to the partition member 1 on one side with the partition member 1 in between, with the wave-shaped ridges extending in a first direction (for example, the vertical direction), and on the other side with the wave-shaped ridges extending in a second direction (for example, the horizontal direction). In other words, two spacing members 2 adjacent to each other with the partition member 1 in between are stacked alternately so that the direction of the wave-shaped ridges on one side and the direction of the wave-shaped ridges on the other side are perpendicular to each other.

[0016] The spacing member 2 and the partition member 1 can be joined using an adhesive or a thermal bonding method that does not use an adhesive. Among these, the method using an adhesive is preferred because it can firmly bond the spacing member 2 and the partition member 1. As the adhesive, known adhesives such as polyvinyl alcohol adhesives and polyvinyl acetate adhesives can be used. A moisture absorbent may also be blended into the adhesive. Examples of moisture absorbents that can be blended include calcium chloride, magnesium chloride, and lithium chloride. Furthermore, the adhesive may also be blended with an anti-mold agent, a thickener, etc.

[0017] Between the spacing member 2, whose ridge lines of the waveforms are oriented in a first direction (for example, the vertical direction), and the partition members 1 on both sides, a plurality of first air flow paths 4 are formed along the first direction. Furthermore, between the spacing member 2, whose ridge lines of the waveforms are oriented in a second direction (for example, the horizontal direction), and the partition members 1 on both sides, a plurality of second air flow paths 5 are formed along the second direction. Note that arrow 6 in FIG. 1 indicates the direction of air flow in the first air flow paths 4, and arrow 7 in FIG. 1 indicates the direction of air flow in the second air flow paths 5.

[0018] Spacing members 2 whose corrugated ridge lines are oriented in a first direction and spacing members 2 whose corrugated ridge lines are oriented in a second direction are alternately stacked with the partition member 1 in between so that the ridge lines are perpendicular to each other, and therefore the first air flow paths 4 and the second air flow paths 5 are also formed so that their extending directions are perpendicular to each other. For example, supply air flows through the first air flow path 4 and exhaust air flows through the second air flow path 5, and heat exchange occurs between the supply air and exhaust air via the partition member 1 and spacing member 2.

[0019] It is preferable that the first direction and the second direction are perpendicular to each other, but the crossing angle between the first direction and the second direction may be adjusted as appropriate depending on the shape of the partition member 1. The crossing angle between the first direction and the second direction may be, for example, 30° to 150°. For example, if the partition member 1 is square, the crossing angle between the first direction and the second direction is preferably 90°, and if the partition member 1 is diamond-shaped, the crossing angle between the first direction and the second direction is preferably close to the angle at which lines connecting the midpoints of opposing sides of the partition member 1 intersect.

[0020] The average pitch of the corrugations of the spacing member 2 is preferably 1.5 to 8 mm, more preferably 2 to 7 mm, and even more preferably 4 to 6.5 mm. The average height of the corrugations of the spacing member 2 is preferably 1 to 5 mm, more preferably 1.3 to 4 mm, and even more preferably 1.5 to 3.5 mm. When the average pitch and average height of the corrugations of the spacing member 2 are equal to or greater than the preferred lower limit values, ventilation of the first air flow path 4 and the second air flow path 5 is more easily ensured. When the average pitch and average height of the corrugations of the spacing member 2 are equal to or less than the preferred upper limit values, contact between the gas passing through the first air flow path 4 and the second air flow path 5 and the partition member 1 is more easily ensured, and heat exchange efficiency is more easily ensured.

[0021] The total heat exchange element 10 is manufactured by alternately laminating the spacing member sheets with both sides of the corrugated ridge lines and valley lines adhered to the partition member sheets, and then cutting them into a predetermined shape. During lamination, spacing member sheets whose corrugated ridge lines are oriented in a first direction and spacing member sheets whose corrugated ridge lines are oriented in a second direction are alternately laminated with the partition member sheets sandwiched between them.

[0022] (Spacing material sheet) The spacing member sheet is a sheet for forming the above-mentioned corrugated spacing member. That is, the spacing member sheet is a spacing member sheet for a total heat exchange element used in a total heat exchange element including a plurality of partition members and a plurality of spacing members that form air flow paths between the plurality of partition members and maintain the spacing between the partition members, and is a flat sheet before the corrugated shape of the spacing member is formed. The spacing member sheet contains cellulose fiber as a main component and further contains a moisture absorbent and a surfactant. By containing the moisture absorbent in the spacing member sheet, it is also possible to prevent the moisture absorbent from leaking from the partition members into the spacing members.

[0023] The spacing member sheet contains cellulose fiber as a main component. Here, "main component" refers to a component that accounts for 50% by mass or more of the total mass of the spacing member sheet. The spacing member sheet is preferably made of pulp containing cellulose fiber. Examples of pulp containing cellulose fiber include wood pulp and non-wood pulp. Examples of wood pulp include softwood pulp and hardwood pulp. Examples of non-wood pulp include hemp pulp, kenaf pulp, and bamboo pulp. As wood pulp, softwood pulp is preferred, as it can further improve base paper strength and CO2 barrier properties, and softwood kraft pulp (NBKP) is more preferred. Furthermore, these pulps may be used alone or in combination of two or more.

[0024] The wood pulp may be one that has been subjected to a cooking process and / or a bleaching process. Generally, wood pulp that has been subjected to various cooking processes and bleaching processes to remove components other than cellulose from raw wood is used. In this embodiment, the cooking process and bleaching process are not particularly limited, and known methods can be used as appropriate.

[0025] The spacing member sheet may further contain fibers other than cellulose fibers, such as synthetic fibers such as rayon fibers, polyethylene fibers, polypropylene fibers, and polyester fibers.

[0026] The spacing member sheet contains a moisture absorbent. Examples of moisture absorbents include inorganic acid salts, organic acid salts, polyhydric alcohols, and ureas. For example, examples of inorganic acid salts include lithium chloride, calcium chloride, and magnesium chloride. Examples of organic acid salts include sodium lactate, calcium lactate, and sodium pyrrolidone carboxylate. Examples of polyhydric alcohols include glycerin, ethylene glycol, triethylene glycol, and polyglycerin. Examples of ureas include urea and hydroxyethyl urea. Among these, it is preferable that the moisture absorbent is at least one selected from the group consisting of calcium chloride and lithium chloride. Note that calcium chloride and magnesium chloride are flame retardant, and therefore, if one or more of these moisture absorbents are retained, the flame retardancy of the spacing member sheet can be enhanced.

[0027] The moisture absorbent may be retained in at least a partial region of the spacing member sheet, but is preferably retained in at least a partial region of both sides of the spacing member sheet, and more preferably retained in the entire region of both sides of the spacing member sheet. The state in which the moisture absorbent is retained on the surface of the spacing member sheet may mean that the moisture absorbent is attached to the surface of the spacing member sheet, or that the moisture absorbent has penetrated into gaps between fibers near the surface of the spacing member sheet. When the moisture absorbent has penetrated into gaps between fibers near the surface of the spacing member sheet, the concentration in the thickness direction of the spacing member sheet may be uniform, or may have a concentration gradient in which the concentration decreases from the surface of the spacing member sheet toward the inside. From the perspective of improving the moisture permeability of the spacing member sheet, it is preferable that the spacing member sheet has a moisture absorbent concentration gradient in which the concentration decreases from the surface of the spacing member sheet toward the inside.

[0028] The moisture absorbent content in the spacing material sheet is 2 The content of the moisture absorbent in the spacing member sheet is preferably 2 g or more, more preferably 3 g or more, and even more preferably 5 g or more per 1 m of the spacing member sheet. 2The moisture absorbent content in the spacing member sheet is preferably 30 g or less, more preferably 20 g or less, and even more preferably 15 g or less per unit area. The moisture absorbent content in the spacing member sheet is calculated as an anhydrous equivalent. By setting the moisture absorbent content within the above range, condensation on the spacing member in the total heat exchange element can be more effectively suppressed. When calcium chloride is used as the moisture absorbent, calcium chloride is highly hygroscopic and typically retains water of crystallization, making it difficult to calculate the dry mass of the moisture absorbent. Therefore, the calcium chloride content can be calculated by multiplying the wet moisture content of an aqueous calcium chloride solution by the concentration of calcium chloride as an anhydrous solution. The concentration of calcium chloride (anhydrous) in an aqueous calcium chloride solution can be determined by EDTA titration.

[0029] When calcium chloride is used as a moisture absorbent, the calcium chloride content is 2 The content of the moisture absorbent in the spacing member sheet is preferably 2 g or more, more preferably 3 g or more, and even more preferably 5 g or more per 1 m of the spacing member sheet. 2 The calcium chloride content is preferably 30 g or less, more preferably 20 g or less, and even more preferably 15 g or less per 1000 sq m. By setting the calcium chloride content within the above range, moisture absorption and desorption performance and flame retardancy can be improved. Furthermore, by setting the calcium chloride content within the above range, condensation on the spacing member can be more effectively suppressed.

[0030] The spacing member sheet contains a surfactant. Examples of the surfactant include anionic surfactants such as alkyl sulfate ester salts, polyoxyethylene alkyl sulfate ester salts, alkylbenzene sulfonates, and α-olefin sulfonates; cationic surfactants such as alkyltrimethylammonium chloride, dialkyldimethylammonium chloride, and benzalkonium chloride; amphoteric surfactants such as trimethylglycine, alkyldimethylaminoacetic acid betaine, and alkylamidodimethylaminoacetic acid betaine; and nonionic surfactants such as ethylene oxide adducts of acetylene glycol, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene glycol and other polyoxyethylene polyoxypropylene ethers, fatty acid esters such as fatty acid sorbitan esters and polyethylene glycol fatty acid esters, alkyl monoglyceryl ethers, alkyl polyglucosides, and fatty acid diethanolamides. Among these, nonionic surfactants are preferred.

[0031] The content of the surfactant in the spacing member sheet is not particularly limited, but it is preferable that the surfactant content in 1 m of the spacing member sheet is 2 Preferably, the surfactant content is 10 g or less, more preferably 5 g or less, and even more preferably 2 g or less per unit area. The lower limit of the surfactant content in the spacing member sheet can be, for example, 0.01 g. By setting the surfactant content within the above range, it is possible to more effectively prevent condensation from occurring on the spacing members in the total heat exchange element. Furthermore, by incorporating a surfactant into the spacing member sheet, the amount of chemical solution absorbed into the spacing member sheet base paper is increased, and as a result, the amount of moisture absorbent retained can also be efficiently increased.

[0032] The spacing member sheet may contain optional components within a range that does not impair the effects of the present invention. Examples of optional components include sizing agents, paper strength agents, colorants, humidity conditioners, mildew inhibitors, and flame retardants. The optional components may be attached to the surface of the spacing member sheet or may be embedded in the gaps between the fibers of the spacing member sheet.

[0033] The Cobb absorbency of the spacing sheet is 30g / m 2 It is preferable that the weight is 35 g / m or more. 2 More preferably, it is 40 g / m or more. 2 It is more preferable that the Cobb water absorbency of the spacing member sheet is 100 g / m or more. 2 Preferably, it is 95 g / m or less. 2 More preferably, it is 90 g / m or less. 2 It is even more preferable that the Cobb water absorbency of the spacing member sheet is a value measured in accordance with JIS P 8140, except that the contact time is 30 seconds. By setting the Cobb water absorbency of the spacing member sheet within the above range, the water retention capacity of the spacing member sheet can be increased, and as a result, the generation of condensation water on the spacing member sheet can be more effectively suppressed.

[0034] The moisture absorption rate of the spacing member sheet is preferably 10% or more, more preferably 12% or more, and even more preferably 15% or more. The moisture absorption rate of the spacing member sheet is preferably 50% or less, more preferably 40% or less, and even more preferably 30% or less. The moisture absorption rate of the spacing member sheet is a value calculated using the following formula. Moisture absorption rate (%)=(BA) / A×100 Here, A is the bone-dry mass of the spacing member sheet when it is placed under conditions of 23°C and 50% relative humidity for 24 hours, conditioned, placed in a weighing bottle (with lid), and dried at 105°C for 1 hour, and B is the conditioned mass when the bone-dried spacing member sheet is placed in a constant temperature and humidity chamber at 20°C and 65% relative humidity for 3 hours.

[0035] The basis weight of the spacing member sheet is 40 g / m 2 It is preferable that the weight is 45 g / m or more. 2 More preferably, it is 50 g / m or more. 2 It is more preferable that the basis weight of the spacing member sheet is 200 g / m or more. 2 Preferably, it is 150 g / m or less.2 More preferably, it is 120 g / m or less. 2 It is even more preferable that the basis weight of the spacing member sheet is less than or equal to 100%. By setting the basis weight of the spacing member sheet within the above range, the thermal conductivity increases and the heat exchange efficiency can be improved. Furthermore, by setting the basis weight of the spacing member sheet within the above range, the water retention can be increased, and the generation of condensation water can be more effectively suppressed. The basis weight of the spacing member sheet is measured in accordance with JIS P 8124 (2011).

[0036] The thickness of the spacing member sheet is preferably 0.03 mm or more, more preferably 0.04 mm or more, and even more preferably 0.05 mm or more. The thickness of the spacing member sheet is preferably 0.2 mm or less, more preferably 0.15 mm or less, and even more preferably 0.12 mm or less. By setting the thickness of the spacing member sheet within the above range, a spacing member sheet that is lightweight yet has excellent mechanical strength can be obtained. Furthermore, by setting the thickness of the spacing member sheet within the above range, the number of stacked spacing members in the total heat exchange element can be increased, thereby further improving heat exchange efficiency. The thickness of the spacing member sheet is measured in accordance with JIS P 8118 (2014).

[0037] (Partition material sheet) The partition member sheet contains cellulose fibers as a main component. Here, "main component" refers to a component that accounts for 50% by mass or more of the total mass of the partition member sheet. The partition member sheet is preferably made of pulp containing cellulose fibers. Examples of pulp containing cellulose fibers include the pulps described above.

[0038] The partition member sheet may further contain fibers other than cellulose fibers, such as synthetic fibers such as rayon fibers, polyethylene fibers, polypropylene fibers, and polyester fibers.

[0039] The partition member sheet preferably contains a moisture absorbent. Examples of the moisture absorbent include those mentioned above. Note that calcium chloride and magnesium chloride have flame retardancy, and therefore, when one or more of these moisture absorbents are held in the sheet, the flame retardancy of the partition member sheet can be enhanced.

[0040] The content of moisture absorbent in the partition material sheet is 2 The content of the moisture absorbent in the sheet for a partition member is preferably 1 g or more, more preferably 2 g or more, and even more preferably 3 g or more per m of the sheet for a partition member. 2 Preferably, the moisture absorbent content is 10 g or less, more preferably 9 g or less, and even more preferably 8 g or less per sheet. The moisture absorbent content in the above-mentioned partition member sheet is an anhydrous equivalent. By setting the moisture absorbent content within the above range, it is possible to more effectively prevent condensation from occurring on the partition member in the total heat exchange element.

[0041] The partition member sheet may contain optional components within a range that does not impair the effects of the present invention. Examples of optional components include sizing agents, paper strength agents, colorants, humidity conditioners, mildew inhibitors, surfactants, flame retardants, polymer resins, etc. The optional components may be attached to the surface of the partition member sheet or may be embedded in the gaps between the fibers of the partition member sheet.

[0042] The basis weight of the partition sheet is 10 g / m 2 It is preferable that the content is 15 g / m or more. 2 The basis weight of the sheet for partition members is more preferably 70 g / m or more. 2 Preferably, it is 40 g / m or less. 2It is more preferable that the basis weight of the partition member sheet is less than or equal to 100%. By setting the basis weight of the partition member sheet within the above range, the thermal conductivity increases and the heat exchange efficiency can be improved. Furthermore, by setting the basis weight of the partition member sheet within the above range, the water retention can be increased, and the generation of condensation water can be more effectively suppressed. The basis weight of the partition member sheet is measured in accordance with JIS P 8124 (2011).

[0043] The thickness of the partition member sheet is preferably 0.008 mm or more, more preferably 0.01 mm or more. The thickness of the partition member sheet is preferably 0.05 mm or less, more preferably 0.03 mm or less. By setting the thickness of the partition member sheet within the above range, a lightweight partition member sheet with excellent mechanical strength can be obtained. Furthermore, by setting the thickness of the partition member sheet within the above range, the number of stacked partition members in the total heat exchange element can be increased, thereby further improving the heat exchange efficiency. The thickness of the partition member sheet is measured in accordance with JIS P 8118 (2014).

[0044] The air permeability of the sheet for partition members is preferably 5000 seconds or more, which improves the gas barrier properties of the partition members.

[0045] To improve gas barrier properties, the partition member sheet may have a coating layer containing a polymer resin on one or both sides of the paper substrate. In this case, examples of the polymer resin include polyvinyl alcohol (PVA). The coating layer is formed by applying a coating liquid containing the polymer resin to the partition member sheet and drying it. The partition member sheet may be porous, and in this case, at least a portion of the coating layer is present in the gaps between the fibers below the surface of the partition member sheet. Alternatively, a portion of the coating layer may be present on the surface of the partition member sheet.

[0046] (Method of manufacturing spacer sheet) The spacing member sheet is produced by applying or impregnating a paper substrate (base paper for spacing member sheet) with a solution (chemical) containing a moisture absorbent and a surfactant. The above-mentioned optional components may be added to the solution (chemical) as needed. When preparing the solution (chemical), it is preferable to mix 0.01 to 10 parts by mass of surfactant per 100 parts by mass of moisture absorbent. By mixing a surfactant, it is possible to more effectively prevent condensation water from forming on spacing members in total heat exchange elements. Furthermore, by mixing a surfactant, it is possible to efficiently adhere the absorbent to the spacing member sheet.

[0047] The paper base material can be produced by papermaking a papermaking raw material containing cellulose fibers. The papermaking raw material may contain other fibers or internal additives as necessary. Any known method can be used to make the papermaking raw material.

[0048] The application or impregnation of the solution (chemical) containing the moisture absorbent and surfactant can be carried out by a known method. For example, after papermaking raw materials are made and dried in a papermaking machine, the solution (chemical) may be applied to the paper substrate in-line using a coating device (size press, gate roll coater, rod coater, blade coater, etc.) in the papermaking machine, and then dried. Alternatively, after the paper substrate is made and dried, the solution (chemical) may be applied to or impregnated into the paper substrate offline using a coating device or impregnation device provided separately from the papermaking machine, and then dried.

[0049] The amount of solution (chemical) to be applied or impregnated is preferably set so that the contents of the moisture absorbent and surfactant in the resulting spacer sheet are within their respective preferred ranges. For example, the amount of solution (chemical) to be applied or impregnated is 10 g / m 2 It is preferable that the content is 20 g / m or more. 2 More preferably, it is 30 g / m or more. 2 It is more preferable that the amount of solution (chemical solution) applied or impregnated is 50 g / m or more. 2 It is preferable that:

[0050] After the solution (chemical) is applied and dried, the resulting spacing member sheet may be subjected to a calendering treatment. Calendering increases the density of the spacing member sheet and reduces its thickness. Increasing the density of the spacing member sheet improves its gas barrier properties, and reducing the thickness of the spacing member sheet improves its thermal conductivity and heat exchange efficiency. There are no particular limitations on the calendering equipment used for the calendering treatment, and known equipment such as a machine calender, soft nip calender, super calender, or gross calender can be used as appropriate.

[0051] The method for manufacturing the sheet for the partition member is not particularly limited, but it can be obtained, for example, by applying and impregnating paper made from highly beaten pulp, such as glassine paper, with a moisture absorbent, and then drying it. [Example]

[0052] The features of the present invention will be explained in more detail below with reference to examples and comparative examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[0053] Example 1 30 parts by mass of calcium chloride (calcium chloride dihydrate, manufactured by Tokuyama Corporation), 0.1 mass of surfactant A (nonionic surfactant (SN Wet 985, manufactured by San Nopco)), and 70 parts by mass of water were placed in a stainless steel container and mixed. Base paper for the spacing member sheet was immersed in the mixed liquid (chemical solution) to impregnate the base paper with the chemical solution. After that, a mangle was used to squeeze out the excess liquid impregnated into the base paper, and the base paper was dried in a drying oven at 105°C to obtain a spacing member sheet. Note that the base paper for the spacing member sheet was bleached kraft paper (manufactured by Oji Materia, basis weight 60 g / m 2 , 130 × 130 mm) was used.

[0054] (Examples 2 to 6 and Comparative Example 1) A spacing member sheet was obtained in the same manner as in Example 1, except that the formulation of the chemical solution was changed as shown in Table 1. As surfactant B, a nonionic surfactant (Venatar NS8, manufactured by Kotani Chemical Co., Ltd.) was used.

[0055] (Measurement and Evaluation) (Chemical solution impregnation amount) The amount of chemical solution impregnated in the spacing member sheets obtained in the examples and comparative examples was calculated from the difference in mass before and after chemical solution impregnation. The content of the moisture absorbent is expressed as an anhydrous calcium chloride equivalent value.

[0056] (Cobb absorbency) The Cobb water absorbency of the spacing member sheet was measured in accordance with JIS P 8140. The contact time was 30 seconds.

[0057] (moisture absorption rate) The spacing member sheets obtained in the examples and comparative examples were subjected to the conditions of 23°C and 50% relative humidity. After 24 hours of conditioning, the sample was placed in a weighing bottle (with a lid) and dried at 105°C for 1 hour, and the bone dry mass (A) was measured. The sample was then placed in a thermo-hygrostat at 20°C and 65% relative humidity for 3 hours, and the conditioned mass (B) was measured. The moisture absorption rate (%) was then calculated using the following formula: Moisture absorption rate (%)=(BA) / A×100

[0058] (Condensation occurrence evaluation (sheet)) The spacing member sheets obtained in the examples and comparative examples were hung in a thermo-hygrostat at 40°C and a relative humidity of 95% for 1 hour, and the occurrence of water droplets on the surface of the spacing member sheets was visually evaluated. ○: No condensation occurs ×: Condensation occurred

[0059] [Table 1]

[0060] Example 7 A chemical solution was obtained in the same manner as in Example 1, except that the compounding amount of the chemical solution was changed as shown in Table 2. This chemical solution was supplied to an impregnation coater, and impregnation coated onto base paper for a spacer sheet. Thereafter, the base paper was dried in a drying oven at 105°C to obtain a spacer sheet.

[0061] (Comparative Examples 2 and 3) A spacing member sheet was obtained in the same manner as in Example 7, except that the amount of the chemical solution was changed as shown in Table 2.

[0062] (Evaluation: Condensation occurrence evaluation (paste)) In addition to the above evaluation items, the spacing member sheets obtained in Example 7 and Comparative Examples 2 and 3 were evaluated for the occurrence of condensation when they were used as laminates. The laminates were produced as follows. First, the spacing member sheet was folded into pleats at 4 mm intervals to form a pseudo-honeycomb. Next, the mountain-folded portion of the pseudo-honeycomb structure was attached to a partition member made of glassine paper impregnated with calcium chloride using an adhesive (EVA) to obtain a one-sided laminated sheet for evaluation. This single-layered sheet (paste) for evaluation was placed in a constant temperature and humidity chamber at 40°C and a relative humidity of 95%. The sheet was left hanging for 24 hours, and the occurrence of water droplets on the surface of the one-tiered sheet was visually evaluated. ○: No condensation occurs ×: Condensation occurred

[0063] [Table 2]

[0064] Compared to the Comparative Examples, the Examples had improved water retention without inhibiting hygroscopicity, and as a result, the occurrence of condensation was suppressed. Furthermore, a comparison of Example 7 with Comparative Examples 2 and 3 revealed that the addition of a surfactant increased the amount of calcium chloride adhered, even when the calcium chloride concentration in the impregnation solution was low. [Explanation of symbols]

[0065] 1 Partition member 2 Spacing members 4 First air flow path 5 Second Air Flow Path 10 Total heat exchange element

Claims

1. A spacing member sheet for a total heat exchange element, which is used in a total heat exchange element including a plurality of partition members and a plurality of spacing members that form air flow paths between the plurality of partition members and maintain the spacing between the partition members, The spacing member sheet contains cellulose fibers as a main component, and the proportion of the cellulose fibers relative to the total mass of the spacing member sheet is 50% by mass or more; further comprising a moisture absorbent and a surfactant; Cobb water absorption: 30 to 100 g / m ２ A sheet for spacing members.

2. 2. The spacing member sheet according to claim 1, wherein the surfactant is at least one selected from alkyl sulfate salts, polyoxyethylene alkyl sulfate salts, alkylbenzene sulfonates, α-olefin sulfonates, alkyltrimethylammonium chloride, dialkyldimethylammonium chloride, benzalkonium chloride, trimethylglycine, alkyldimethylaminoacetic acid betaine, alkylamidodimethylaminoacetic acid betaine, an ethylene oxide adduct of acetylene glycol, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene glycol, fatty acid sorbitan ester, polyethylene glycol fatty acid ester, alkyl monoglyceryl ether, alkyl polyglucoside, and fatty acid diethanolamide.

3. 3. The spacing member sheet according to claim 1, wherein the moisture absorbent is at least one selected from the group consisting of calcium chloride and lithium chloride.

4. The content of the moisture absorbent is ２ The spacing member sheet according to any one of claims 1 to 3, wherein the weight is 2 to 30 g per sheet.

5. A method for manufacturing the spacing member sheet according to any one of claims 1 to 4, A sheet containing cellulose fiber as its main component, A method for manufacturing a spacing member sheet, which comprises applying or impregnating a sheet with a solution containing a moisture absorbent and a surfactant.

6. A total heat exchange element comprising a plurality of spacing members made of the spacing member sheet according to any one of claims 1 to 4 and a plurality of partition members, The spacing member forms an air flow path between the plurality of partition members and maintains a distance between the partition members.

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