JP6094745B2 - Sorbent coating liquid, sorbent-carrying metal plate coated with the sorbent coating liquid, and heat exchanger having the sorbent-carrying metal plate - Google Patents

Description

The present invention relates to a sorbent coating liquid, a sorbent-carrying metal plate formed by applying the sorbent coating liquid, and a heat exchanger having the sorbent-carrying metal plate.

Conventionally, an adsorption heat exchanger such as an adsorption refrigerator or an adsorption air conditioner is known as an application of a metal plate carrying an adsorbent. This type of adsorption heat exchanger is disclosed in, for example, Patent Documents 1, 2, and 3.

As the adsorbent supported on the metal substrate of the adsorption heat exchanger, an inorganic adsorbent such as silica gel or zeolite is used in Patent Document 1, and a polymer sorbent is used in Patent Documents 2 and 3. Yes.

The organic polymer sorbents disclosed in Patent Documents 2 and 3 have the property of swelling and shrinking by absorbing and releasing moisture. Due to this flexible structure, the moisture absorption performance is not reduced due to the structural destruction due to repeated moisture absorption and release seen in inorganic materials. Moreover, a large amount of water can be absorbed as compared with the inorganic adsorbent.

However, since organic polymer sorbents have the property of swelling when they contain water, when preparing a sorbent coating film by preparing a coating solution using a solvent containing a lot of water, There is a problem that cracks occur in the sorbent coating film formed by the volume change from the swelling of the organic polymer sorbent to the contracted state during drying. Moreover, there was a problem that the adhesion with the substrate was poor and the sorbent coating film was peeled off under conditions such as submersion. In contrast to the former problem, Patent Document 3 discloses a method in which an organic polymer sorbent is supported on a heat exchanger in a contracted state, which is used as an alcohol solvent main solvent. However, the amount of water in the slurry must be strictly controlled. Moreover, in this example, the problem regarding the adhesion to the substrate to be carried is not discussed.

JP-A-5-322364 JP 2006-200850 A JP 2010-270972 A

As described above, the sorbent-supporting metal plate using the organic polymer sorbent has a problem of cracking or peeling of the sorbent layer. The present invention was devised in view of the current state of the prior art, and the purpose thereof is a sorbent coating liquid that does not cause cracking and peeling problems, and a metal plate formed by applying the coating liquid, A further object is to provide a heat exchanger.

As a result of diligent investigations, the present inventors have found that the above object can be achieved by the presence of a cationic polymer having a charge opposite to that of the organic polymer sorbent in a solvent system containing a large amount of water. The headline, the present invention has been reached.

That is, the present invention is achieved by the following means.
(1) Organic polymer sorbent particles composed of an organic polymer having a carboxyl group and a crosslinked structure, a sorption containing a cationic polymer, a binder resin, alcohol and water adhering to the surface of the sorbent Agent coating solution.
(2) The sorbent coating solution according to (1), comprising 100 to 500 parts by weight of water with respect to 100 parts by weight of the organic polymer sorbent.
(3) The sorbent coating solution according to (1) or (2), wherein the cationic polymer is a cationic urethane resin.
(4) The sorbent coating solution according to any one of (1) to (3), wherein the binder resin is a neutral urethane resin or a weak anionic urethane resin.
(5) The sorbent coating solution according to any one of (1) to (4), which contains polyvinyl alcohol.
(6) A sorbent-supporting metal plate having a sorbent layer formed on the metal plate by applying the sorbent coating solution according to any one of (1) to (5), and sorption A sorbent-supporting metal plate, comprising an anionic primer layer between the agent layer and the metal plate.
(7) A heat exchanger having the sorbent-carrying metal plate according to (6).

By using the present invention, even in a solvent system containing a large amount of water, the amount of binder used to suppress cracking of the sorbent layer to be formed can be reduced. It is possible to suppress a decrease in the moisture absorption amount and moisture absorption rate of the adhesive particles. For this reason, it is effective for a batch type dehumidification system that absorbs a large amount of moisture for a long time, a desiccant rotor that repeatedly absorbs and releases moisture in a short time, and the like. Furthermore, by reducing the hydration of the organic polymer sorbent particle surface, the adhesion to the binder and the adhesion to the substrate are improved, and a more uniform sorbent layer can be formed. .

● About Sorbent The organic polymer sorbent particles employed in the present invention have a carboxyl group in the molecule and have a crosslinked structure. The carboxyl group present in the organic polymer sorbent particles has a characteristic of chemically adsorbing moisture in the air. The carboxyl group is preferably in a salt form, and the cations forming a pair are not particularly limited, and examples thereof include alkali metals such as Li, Na, K, Rb, and Cs, Be, Mg, Ca, Sr, Ba, and the like. Alkaline earth metals, other metals such as Cu, Zn, Al, Mn, Ag, Fe, Co, and Ni, organic cations such as NH ₄ and amine, and the like can be mentioned. Of these, alkali metal and alkaline earth metal cations are preferred from the viewpoint of moisture absorption / release rate.

The amount of carboxyl group is preferably 1 to 10 mmol / g, more preferably 3 to 10 mmol / g. When the carboxyl group amount is less than 1 mmol / g, sufficient moisture absorption / release performance may not be obtained. When the carboxyl group amount exceeds 10 mmol / g, the organic polymer sorbent particles absorb water and swell greatly. Furthermore, since the volume change due to swelling and shrinkage becomes very large in the obtained sorbent layer, the durability of the sorbent layer becomes insufficient. Here, when the sorbent having a cross-linked structure contains a salt-type carboxyl group, the carboxyl group amount represents the mol amount of the carboxyl group relative to the polymer weight when all the carboxyl groups of the polymer are acid-type. Is.

Further, the crosslinked structure of the organic polymer sorbent particles reduces moisture swelling or particle swelling that occurs when water is absorbed. Such a crosslinked structure is not particularly limited as long as it is not physically or chemically modified in accordance with moisture absorption or desorption, and any of such as crosslinking by covalent bond, ionic crosslinking, interaction between polymer molecules, or crosslinking by crystal structure, etc. The thing of the structure of may be sufficient. Among these, a crosslinked structure by a covalent bond is most preferable from the viewpoint of strength and stability.

There is no limitation on the degree of crosslinking of the organic polymer sorbent particles, but the organic polymer sorbent particles absorb water or absorb moisture, as described in the production method described later, When the crosslinked structure is introduced by copolymerization of a crosslinking monomer, the degree of crosslinking calculated by the following formula is preferably 8 or more.
Crosslinking degree = crosslinking monomer (mol) / total monomer (mol) × 100

The particle diameter of the organic polymer sorbent particles employed in the present invention is preferably 1 to 60 μm. Especially, a thing with a particle diameter of 5-50 micrometers is preferable. When the particle diameter is too small, the amount of the binder resin for binding the respective particles increases, so that the coating of the binder resin covers the particles, resulting in a decrease in the moisture absorption rate. On the other hand, if the particle size is too large, the dispersibility of the particles in the solvent in the coating solution will be reduced, making uniform coating difficult, and reducing the hygroscopic performance by reducing the surface area of the organic polymer sorbent particles. Will occur.

Examples of the method for producing organic polymer sorbent particles having a crosslinked structure as described above include the following methods.
(1) Method of copolymerizing monomer having carboxyl group and crosslinking monomer (2) Method of hydrolyzing copolymer of monomer capable of deriving carboxyl group and crosslinking monomer (3) Reactive crosslinking agent for polymer having carboxyl group (4) A method in which a polymer having a functional group capable of deriving a carboxyl group is crosslinked with a reactive crosslinking agent and hydrolyzed.

In the method (1), examples of the monomer having a carboxyl group include monomers having a carboxylic acid group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, vinylpropionic acid, and carboxylates of these monomers. Etc.

In the method (2), examples of monomers capable of deriving a carboxyl group include monomers having a nitrile group such as acrylonitrile and methacrylonitrile; carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, and vinyl propionic acid. Examples thereof include anhydrides, ester derivatives and amide derivatives of monomers having a group. The functional group of these monomers is converted into a carboxyl group by undergoing hydrolysis.

The crosslinking monomer is not particularly limited as long as it has two or more double bonds in the molecule. For example, glycidyl methacrylate, N-methylolacrylamide, triallyl isocyanurate, triallyl cyanurate, divinylbenzene, Examples thereof include crosslinkable vinyl compounds such as hydroxyethyl methacrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and methylenebisacrylamide. Among these, the cross-linked structure by triallyl isocyanurate, triallyl cyanurate, divinylbenzene, and methylene bisacrylamide is also used for hydrolysis to introduce carboxyl groups to be applied to cross-linked copolymers containing them. It is desirable for use in the case of obtaining a carboxyl group through a hydrolysis step.

As for hydrolysis, a method of heat-treating a cross-linked copolymer obtained by copolymerization in a basic aqueous solution such as an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or sodium carbonate or ammonia. Can be adopted. Here, since the carboxyl group produced | generated by hydrolysis forms a cation and a salt corresponding to the chemical | medical agent used for a hydrolysis, it is desirable to select the chemical | medical agent used for a hydrolysis also considering a desired salt type. In addition, it is also possible to change the salt type of a carboxyl group by performing a treatment with an acid or a metal salt aqueous solution after hydrolysis.

In the method (4), the polymer having a functional group capable of deriving a carboxyl group is obtained by, for example, copolymerizing a monomer capable of deriving a carboxyl group and a monomer having a functional group capable of reacting with a reactive crosslinking agent. Can be obtained. The monomer having a functional group capable of reacting with the reactive crosslinking agent is selected according to the type of the reactive crosslinking agent used. As a specific method, for example, in a nitrile polymer in which the content of a vinyl monomer having a nitrile group is 50% by weight or more, the nitrile group is reacted with a hydrazine compound, polyamine, formaldehyde, or the like to crosslink, The method of hydrolyzing the nitrile group etc. which were not concerned in bridge | crosslinking similarly to the method of said (2) can be mentioned.

Cationic polymer A cationic polymer has at least one or more primary to tertiary amino groups or quaternary ammonium groups in the molecule, and is positively charged when the polymer chain is ionized in an aqueous solution. It can be a polymer. This positively charged polymer is ionically bonded to the surface of the organic polymer sorbent particles that are anionic polymers, and as a result, the hydration of the organic polymer sorbent particles is reduced, and the binder It is considered that the adhesion with the resin component can also be improved.

The cationic polymer covers the surface of the organic polymer sorbent particles, thereby reducing the hydration of the particles and improving the adhesion between the binder resin and the particles. Those having a quaternary ammonium group that is easily charged as a functional group are preferred. Further, when the cationic polymer is water-soluble or redispersible, there is a concern about the water resistance of the sorbent layer. Therefore, an aqueous emulsion that does not redisperse in water after drying is preferable. Among these, a cationic urethane resin excellent in adhesion to the binder resin, moisture permeability, and the like is preferable.

The addition amount of the cationic polymer is 1 to 30 parts by weight and particularly preferably 5 to 20 parts by weight with respect to 100 parts by weight of the sorbent. When the addition amount is decreased, the adhesion is lowered, and conversely, when the addition amount is increased, the ratio of the organic polymer sorbent particles is decreased, and thus the moisture absorption rate of the formed sorbent layer is lowered.

● Binders With only cationic polymers, the ability to bond organic polymer sorbent particles is weak, the sorbent layer formed becomes brittle, and it is difficult to maintain the sorbent layer under submerged conditions. There are cases. For this reason, the binder resin preferably has adhesion between the organic polymer sorbent particles and the cationic polymer and also has adhesion with the primer layer applied on the metal plate. Further, the binder resin is preferably one that can follow the volume change with respect to the shrinkage during drying and the swelling during wetness of the organic polymer sorbent particles in the formed sorbent layer. What is 50 degrees C or less is preferable. Examples of such a resin that can be a binder resin include urethane resins, acrylic resins, and epoxy resins. From the viewpoint that it is difficult to form an aggregate with a cationic polymer in a coating solution, the resin is neutral or weakly anionic. Resins are preferred. Among these, a water-based urethane resin that is excellent in adhesion and moisture permeability and has good dispersibility in the coating liquid is particularly preferable.

The ratio of the binder resin is 20 to 100 parts by weight, particularly preferably 30 to 50 parts by weight, based on 100 parts by weight of the organic polymer sorbent particles. If the ratio of the binder resin is too large, the binder resin portion that covers the organic polymer sorbent particles may increase, resulting in a decrease in the moisture absorption rate. If the ratio is too small, the sorbent layer may be cracked or the adhesiveness may be decreased. May cause.

If the coating amount of the sorbent coating solution is reduced, it becomes difficult to form a homogeneous sorbent layer. However, by adding a polymer with good adhesion and film-forming properties such as polyvinyl alcohol to the binder resin, sorption can be achieved. The film forming property of the agent coating solution can be improved. If polyvinyl alcohol is used, the addition amount is 1 to 10 parts by weight, preferably 2 to 8 parts by weight, based on 100 parts by weight of the organic polymer sorbent particles. If the amount added is too large, the viscosity of the sorbent coating solution may become too high, making it difficult to apply, or reducing the moisture absorption rate. On the other hand, if the amount is too small, the effect of improving the film forming property will be sufficient. It may not be obtained.

● Alcohol and water The alcohol solvent is added mainly for the purpose of diluting the sorbent coating liquid, defoaming and improving the drying speed. The type of alcohol used in preparing the sorbent coating liquid is not particularly limited, but the higher the alcohol, the more easily the water-dispersed resin is dissolved, and the viscosity of the coating liquid increases and the coating property increases. Therefore, it is preferable that ethanol and methanol, which are lower alcohols, are used as the main components. In consideration of wettability with the base material, ethanol is preferable.

The alcohol content in the sorbent coating liquid is 20 to 500 parts by weight, particularly 100 to 300 parts by weight, based on 100 parts by weight of the organic polymer sorbent particles. On the other hand, the water contained in the sorbent coating liquid is derived from the cationic polymer and the binder resin component, and the total amount of water added when adjusting the sorbent coating liquid is 100 wt. The amount is 100 to 500 parts by weight, preferably 100 to 300 parts by weight. If too much water is contained in the sorbent coating solution, the sorbent layer that is previously supported in the case of coating with two or more coats, the adhesiveness with the substrate is lowered, the drying speed is lowered, This causes a problem that it becomes difficult to run out of liquid due to water absorption and swelling.

About Coating Solution The sorbent coating solution of the present invention comprises the organic polymer sorbent particles, the cationic polymer, the binder resin, water, and alcohol as essential components. In addition to the essential components, antibacterial agents, preservatives, and the like may be added as long as the moisture absorption performance is not impaired. As a method for preparing the sorbent coating liquid, organic polymer sorbent particles are dispersed in a dispersion medium composed of water and alcohol, and then a cationic polymer is added and stirred sufficiently, and then a binder resin is added. The method of compounding is mentioned. When other additives are used, they can be added after the above-mentioned preparation.

● Metal plate The material of the metal plate is not particularly limited, and examples include an aluminum plate, an iron plate, a stainless steel plate, and a copper plate. When using a metal plate carrying a sorbent layer for a heat exchanger or the like, it is particularly preferable to use an aluminum plate because of its high thermal conductivity, light weight and low cost. With respect to the application method of the sorbent coating liquid described above, centrifugal separation from impregnation, application using a bar coder, a blade, or the like, or a spraying method of the sorbent coating liquid may be mentioned. The coating amount is not particularly limited, but if the coating amount is too large, cracking of the sorbent layer is likely to occur, or conversely, if the coating amount is too small, it becomes difficult to form a uniform sorbent layer. That is, as a carrying amount after drying, 20 to 200 g / m ² is preferable, and 50 to 150 g / m ² is more preferable.

-About an anionic primer layer An anionic primer layer improves the adhesiveness of the sorbent layer to a metal plate. That is, when the anionic primer layer is not provided on the metal plate, the wettability with respect to the sorbent coating liquid is poor and uniform application is difficult. Furthermore, the adhesion between the formed sorbent layer and the metal plate is also lowered.

Moreover, even in the case of a metal plate having an anionic primer layer, if the cationic polymer is not added to the sorbent coating solution, the adhesion between the metal plate and the sorbent layer is greatly reduced. Therefore, it is assumed that the sorbent layer and the anionic primer layer exhibit adhesion by electrical attraction.

The method for forming the anionic primer layer on the metal plate is not particularly limited, and a method such as coating can be employed. Here, the anionic primer to be applied to the metal plate is desirably applied so as to cover the entire surface of the metal plate, and the application amount is preferably 1 to 15 g / m ² , more preferably ^{2 to} 10 g / m ² . a m ^2.

The anionic primer forming such an anionic primer layer preferably has both adhesion to the metal plate and adhesion to the sorbent layer, and has both water resistance and corrosion resistance. Specific examples include urethane resins, acrylic resins, and epoxy resins.

About heat exchanger As the heat exchanger of the present invention, for example, a heat exchanger in which a sorbent-supporting metal plate produced by the above method is processed into fins and assembled together with other members, or a shape And a heat exchanger in which a sorbent layer is supported by the above-described method. The shape of the heat exchanger is not particularly limited. For example, a rotor type obtained by winding a corrugated metal plate, a block type obtained by stacking, or an interval of 0.5 to 5.0 mm. A structure in which a heat transfer tube is penetrated through a large number of arranged fins is exemplified.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In addition, unless otherwise indicated, the part and percentage in an Example are shown on a weight basis. First, an evaluation method for each characteristic and a notation method for evaluation results will be described.

[Average particle size]
Using a laser diffraction particle size distribution analyzer “SALD-200V” manufactured by Shimadzu Corporation, water was used as a dispersion medium, and the average particle size was determined from the particle size distribution expressed on a volume basis.

[Amount of carboxyl group]
1 g of a well-dried sample is precisely weighed (X [g]), 200 ml of water is added thereto, and 1N hydrochloric acid aqueous solution is added to adjust the pH to 2 while heating to 50 ° C. All of the carboxyl groups were converted to H-type carboxyl groups, and then a titration curve was obtained with a 0.1 N NaOH aqueous solution according to a conventional method. From the titration curve, the consumption amount of NaOH aqueous solution (Y [ml]) consumed by the H-type carboxyl group was determined, and the amount of carboxyl group contained in the sample was calculated by the following formula.
Amount of carboxyl group [mmol / g] = 0.1 Y / X

[Saturated moisture absorption]
First, the saturated moisture absorption rate of the sorbent layer refers to a value obtained by the following method. A sorbent layer is formed on an aluminum plate (including primer treatment) (Wp [g]) whose weight has been measured in advance by the same method as in the example, and the sorbent-carrying aluminum plate is used as a measurement sample. The sorbent-carrying aluminum plate is dried with a hot air dryer at 120 ° C. for 1 hour and weighed (Wds [g]), and then the sample is adjusted to a relative humidity of 65% RH at a temperature of 20 ° C. The sample is left in the vessel for 16 hours and the weight of the absorbed sample is measured (Wws [g]). Based on the above results, the saturated moisture absorption rate is calculated by the following equation.
Saturated moisture absorption (wt%) = {(Wws−Wds) / (Wds−Wp)} × 100

[Moisture absorption speed]
The moisture absorption rate was measured as follows. A sorbent layer was applied to a 5 × 8 cm aluminum plate so as to have an application amount of 50 g / m ² to obtain a sample for moisture absorption rate. The obtained sample is dried at 120 ° C. for 1 hour, and then moisture-absorbed for 1 minute in a constant temperature and humidity chamber at 20 ° C. and 65% RH. After drying at this time, the amount of moisture absorption was measured from the difference in sample weight after moisture absorption for 1 minute.

[Residual rate of sorbent layer due to submersion (adhesion of sorbent layer)]
The residual ratio in submersion as an index representing the adhesion of the sorbent layer to the substrate is measured as follows. The sorbent layer is supported on a 5 × 8 cm size aluminum plate (including primer treatment) (Wp [g]) so that the coating amount is 50 g / m ² , dried at 120 ° C. for 1 hour, and then dried weight Is measured (Wds1 [g]). The obtained sorbent-carrying aluminum plate was immersed in a 50 ° C. water bath for 1 hour and then dried at 120 ° C. for 1 hour five times, and then the dry weight was measured ( Wds2 [g]). Based on the above results, the remaining rate is calculated by the following equation.
Residual rate (%) = {(Wds2-Wp) / (Wds1-Wp)} × 100
This value is a numerical value representing the water resistance of the sorbent-carrying aluminum plate, and it can be determined that the higher the value, the higher the water resistance. In addition, the surface state of the sorbent layer before and after the test was evaluated visually according to the following criteria, and the water resistance was comprehensively evaluated including the shape maintenance of the sorbent layer.
◎: No cracking ○: Little cracking △: There are a few cracks ×: Many cracks

[Production of organic polymer sorbent particles]
A monomer mixture consisting of 55 parts of acrylonitrile, 10 parts of methyl acrylate, and 35 parts of divinylbenzene is added to 300 parts of an aqueous solution containing 0.5 part of ammonium persulfate, and then 0.6 part of sodium pyrosulfite is added, followed by polymerization with a stirrer. Polymerization was carried out in a tank at 65 ° C. for 2 hours. 15 parts of the obtained particles are dispersed in 85 parts of water, 10 parts of sodium hydroxide are added thereto, and after hydrolysis reaction at 90 ° C. for 2 hours, washing, dehydration and drying are performed, and an organic polymer is obtained. System sorbent particles were obtained. The degree of crosslinking of the particles was 19, the average particle size was 30 μm, and the amount of carboxyl groups was 6.3 mmol / g.

[Example 1]
To 100 parts by weight of the organic polymer sorbent particles dried at 120 ° C. for 16 hours or more, 130 parts by weight of water and 127 parts by weight of ethanol are added and stirred. 33 parts by weight of a water-dispersed urethane resin, Superflex 620 (solid content 30%, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a cationic polymer was added to this mixed solution and stirred for 1 hour. To this, 77 parts by weight of water-dispersed neutral urethane resin diluted to 40% solids, Superflex E-2000 (50% solids, glass transition point -38 ° C., manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added. Stirring was performed to obtain a coating solution. The ratio of water in the coating solution was 200 parts by weight with respect to 100 parts by weight of the organic polymer sorbent particles.

Next, the aluminum plate was coated with Superflex 170 (Daiichi Kogyo Seiyaku Co., Ltd.), which is an anionic urethane resin, as an anionic primer so that the supported amount was 5 g / m ² .
The sorbent coating solution was applied onto the aluminum plate so as to have the coating amount shown in Table 1 using a bar coder. After coating, preliminary drying was performed at room temperature, followed by drying at 120 ° C. for 1 hour to obtain a sorbent-carrying aluminum plate. The evaluation results of the obtained sorbent-carrying aluminum plate are shown in Table 1. As can be seen from Table 1, the obtained sorbent-carrying aluminum plate had few cracks in the sorbent layer and had a good surface state even after the submergence test.

[Example 2]
To 100 parts by weight of the organic polymer sorbent particles dried at 120 ° C. for 16 hours or more, 105 parts by weight of water and 168 parts by weight of ethanol are added and stirred. 34 parts by weight of a water-dispersed urethane resin, Superflex 620 (solid content 30%, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as a cationic polymer was added to this mixed solution and stirred for 1 hour. To this was added 75 parts by weight of a water-dispersed neutral urethane resin diluted to 40% solids, Superflex E-2000 (50% solids, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and then 30% of a 10% polyvinyl alcohol aqueous solution. Part was added and sufficiently stirred to obtain a coating solution. Using the obtained coating solution, a sorbent-carrying aluminum plate was produced in the same manner as in Example 1. The sorbent-carrying aluminum plate obtained as shown in Table 1 showed high adhesion as in Example 1, and had a good surface state even after the submergence test. Further, in Example 2, the surface state was better than that in Example 1 even in the low adhesion amount region with an application amount of 25 / m ² , and the film forming property was high.

[Example 3]
99 parts by weight of water and 160 parts by weight of ethanol are added to 100 parts by weight of organic polymer sorbent particles dried at 120 ° C. for 16 hours or more and stirred. To this mixed solution, 67 parts by weight of a 15% polyallylamine aqueous solution was added and stirred for 1 hour. To this, 75 parts by weight of water-dispersed neutral urethane resin diluted to 40% solids, Superflex E-2000 (50% solids, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was added and sufficiently stirred to obtain a coating solution. It was. Using the obtained coating solution, a sorbent-carrying aluminum plate was produced in the same manner as in Example 1. As shown in Table 1, the obtained sorbent-carrying aluminum plate is almost free from cracks in the sorbent layer after coating and drying as in Examples 1 and 2, and even when the submergence test is repeated. The layer did not peel off. In addition, when the submergence test was repeated, cracking was likely to occur in the sorbent layer compared to Examples 1 and 2, but this was because the polyallylamine, which is a water-soluble polymer, was subjected to an organic polymer system by submergence test. This is thought to be due to desorption from the surface of the sorbent particles.

[Comparative Example 1]
A sorbent-carrying aluminum plate was produced in the same manner as in Example 1 except that the aluminum plate was not subjected to primer treatment. As shown in Table 1, the obtained sorbent-supporting aluminum plate had a surface state almost equivalent to that of Example 1, but in the submergence test, the sorbent layer was completely peeled off and an anionic primer treatment was performed. In the absence, it was confirmed that the sorbent layer and the aluminum plate had no adhesion.

[Comparative Example 2]
To 100 parts by weight of organic polymer sorbent particles dried at 120 ° C. for 16 hours or more, 155 parts by weight of water and 135 parts by weight of ethanol are added and stirred. To this mixed solution, 75 parts by weight of water-dispersed neutral urethane resin diluted to 40% solids, Superflex E-2000 (50% solids, manufactured by Daiichi Kogyo Seiyaku) was added to obtain a coating solution. As in Example 1, the ratio of water in the coating solution was 200 parts by weight with respect to 100 parts by weight of the organic polymer sorbent particles. A sorbent-carrying aluminum plate was produced according to Example 1 using the obtained coating solution. As shown in Table 1, since the sorbent-carrying aluminum plate obtained in Comparative Example 2 does not use a cationic polymer, many cracks in the sorbent layer were observed in the drying process. Moreover, by repeating the submergence test, the sorbent layer was further made brittle, and detachment from the substrate was observed.

[Comparative Example 3]
To 100 parts by weight of the organic polymer sorbent particles dried at 120 ° C. for 16 hours or more, 130 parts by weight of water and 103 parts by weight of ethanol are added and stirred. To this was added 100 parts by weight of a water-dispersed urethane resin, Superflex 620 (solid content 30%, manufactured by Daiichi Kogyo Seiyaku) as a cationic polymer, and the mixture was stirred for 1 hour to obtain a coating solution. A sorbent-carrying aluminum plate was produced according to Example 1 using the obtained coating solution. As shown in Table 1, the sorbent-carrying aluminum plate obtained in Comparative Example 3 had a good surface condition of the sorbent layer at the time of coating and drying as in Example 1, but the submergence test By repeating the above, it was observed that organic polymer sorbent particles dropped out from the sorbent layer. This is presumably because the binder polymer is not added and the cationic polymer alone is weak in bonding organic polymer sorbent particles.

Claims (7)

Organic polymer sorbent particles comprising an organic polymer having a carboxyl group and a crosslinked structure, a sorbent coating containing a cationic polymer, a binder resin, alcohol and water adhering to the surface of the sorbent liquid. The sorbent coating solution according to claim 1, comprising 100 to 500 parts by weight of water with respect to 100 parts by weight of the organic polymer sorbent. The sorbent coating solution according to claim 1, wherein the cationic polymer is a cationic urethane resin. The sorbent coating liquid according to any one of claims 1 to 3, wherein the binder resin is a neutral urethane resin or a weak anionic urethane resin. Polyvinyl alcohol is contained, The sorbent coating liquid in any one of Claims 1-4 characterized by the above-mentioned. It is a sorbent carrying | support metal plate which has a sorbent layer formed by apply | coating the sorbent coating liquid in any one of Claims 1-5 on a metal plate, And between a sorbent layer and a metal plate A sorbent-carrying metal plate characterized by having an anionic primer layer. A heat exchanger comprising the sorbent-carrying metal plate according to claim 6.