JP2014196380A - Method for manufacturing coated heat storage microcapsule, method for manufacturing heat storage material, and adsorbent with heat storage function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a coated heat storage microcapsule having high solvent resistance and high water resistance, positively maintaining the heat storage function, and capable of easily and stably manufacturing a granulated heat storage material, to provide a method for manufacturing a heat storage material, and to provide an adsorbent with a heat storage function.SOLUTION: A method for manufacturing a coated heat storage microcapsule 3B comprises: a first coating step of mixing a dispersion liquid containing a heat storage microcapsule and a hydrophilic polymer compound 5 to produce a coated heat storage microcapsule 3A having a coating film of the hydrophilic polymer compound 5 formed on the surface of the outer shell of the heat storage microcapsule; and a second coating step of mixing a dispersion liquid 3b containing the coated heat storage microcapsule 3A and a phenol resin 6 to produce a mixed dispersion liquid 3c and then manufacturing a coated heat storage microcapsule powder 4 having formed on at least a part of the surface of the coated heat storage microcapsule 3A a coated portion 7 to which the phenol resin 6 adheres by spraying and drying the mixed dispersion liquid 3c.

Description

  The present invention relates to a method for producing a coated thermal storage microcapsule in which a coating portion is formed on a thermal storage microcapsule in which a phase change substance that absorbs and releases latent heat according to a temperature change is enclosed in an outer shell made of a polymer compound The present invention relates to a method for producing a heat storage material obtained by granulating a coated heat storage microcapsule produced by the production method, and an adsorbent with a heat storage function obtained by mixing a heat storage material produced by the production method and an adsorbent.

The adsorbent that is a porous body has a characteristic that the adsorption capacity increases as the temperature decreases, and the adsorption capacity decreases as the temperature increases. Therefore, in order to improve the adsorption / desorption performance of the adsorbent, a technique for suppressing temperature change of the adsorbent by suppressing heat generation / endotherm has been desired.
In order to suppress such heat generation and heat absorption, a heat storage material including a heat storage microcapsule in which a phase change material that absorbs and releases latent heat according to a temperature change is enclosed in an outer shell, and an adsorbent Adsorbents with a heat storage function that are used in contact with each other are disclosed (see Patent Documents 1 to 5).

  Using such an adsorbent with a heat storage function, for example, to prevent vaporized fuel (organic solvent) such as gasoline supplied to an internal combustion engine such as a vehicle from being released to the outside (in the atmosphere, etc.) However, at this time, the absorption of latent heat by the heat storage material and the deterioration of the release performance may become a problem due to the organic solvent, moisture in the air, or the like. Specifically, when the organic solvent breaks or permeates the outer shell of the heat storage microcapsule, the phase change material enclosed in the outer shell may leak to the outside, and the moisture in the air, etc. However, even if the outer shell of the heat storage microcapsule is deteriorated, the outer shell may be destroyed, and the phase change material enclosed in the outer shell may leak to the outside. In addition, there is a possibility that the outer shell is destroyed when the phase change material enclosed in the outer shell expands and contracts according to the temperature change. In such a case, the heat storage function of the heat storage microcapsule may be lowered, and the adsorption / desorption performance of the heat storage function-attached adsorbent may be reduced.

  Therefore, for example, as a method for producing a heat storage microcapsule used for an adsorbent with a heat storage function, polyvinyl alcohol is added to a capsule dispersion liquid containing heat storage microcapsules (see Patent Documents 1 and 2), and water is added to polyvinyl alcohol. Addition of crosslinking agents such as reactive melamine resin and polyfunctional epoxy resin (see Patent Documents 1 and 3), addition of cationic polyacrylamide and addition of buffering agents and dispersants (see Patent Document 4), cationic self-crosslinking A method for producing a coated heat storage microcapsule in which polyvinyl alcohol is added in addition to a resin having a property (see Patent Document 5) to form a coating portion of polyvinyl alcohol on the surface of the outer shell of the heat storage microcapsule is disclosed. It is disclosed to improve water resistance, durability and solvent resistance.

  In addition, for example, after the heat storage microcapsule is manufactured by the method for manufacturing the heat storage microcapsule, the periphery of the contact portion between the heat storage microcapsules is combined with a molding binder and formed into a granulated heat storage material, and then the granulated heat storage material is removed. A technique has been disclosed in which a coating layer is formed by coating a surface portion with a coating binder, and a coating granulation heat storage material on which the coating layer is formed is subjected to a reaction promotion treatment that accelerates the polymerization reaction of the coating binder ( Patent Document 6), improving water resistance, durability, and solvent resistance is disclosed.

JP 2001-058126 A JP 2008-221046 A JP 2008-132425 A JP 2008-184524 A JP 2006-176761 A International Publication No. 2009/145020

  However, according to the method for producing a heat storage microcapsule described in Patent Documents 1 to 5 above, a coating portion made of polyvinyl alcohol or the like is formed on the surface of the outer shell of the heat storage microcapsule to improve water resistance and solvent resistance. However, it is desired to have higher water resistance and solvent resistance. Moreover, according to the above-mentioned Patent Document 6, a heat storage microcapsule can be bonded with a molding binder to produce a granulated heat storage material, but when the granulated heat storage material is manufactured, it is easier and more stable to granulate. It was necessary to develop possible heat storage microcapsules.

  The present invention has been made in view of the above-mentioned problems, and the object thereof is to provide a high heat resistance and water resistance, and to reliably maintain heat storage performance, and to more easily and stably granulate heat storage material. It is in the point which provides the technique regarding the manufacturing method of the coating thermal storage microcapsule which can manufacture, the manufacturing method of the thermal storage material using the coating thermal storage microcapsule, and the adsorption material with a thermal storage function.

In order to achieve the above object, a method for producing a coated thermal storage microcapsule according to the present invention is formed by encapsulating a phase change material that absorbs and releases latent heat in accordance with a temperature change in an outer shell made of a polymer compound. A method for producing a coated thermal storage microcapsule in which a coating portion is formed on the thermal storage microcapsule, the characteristic means being
First, a dispersion containing the heat storage microcapsule and a hydrophilic polymer compound are mixed to produce a film heat storage microcapsule in which a coating of the hydrophilic polymer compound is formed on the surface of the outer shell of the heat storage microcapsule. A coating process;
A dispersion containing the film heat storage microcapsule and a phenol resin are mixed to form a mixed dispersion, the mixture dispersion is spray-dried, and the phenol is applied to at least a part of the surface of the film of the film heat storage microcapsule. And a second coating step for producing a coated heat storage microcapsule powder on which a coating portion formed by adhering a resin is formed.

According to this characteristic means, in the first coating step, the dispersion liquid containing the heat storage microcapsules and the hydrophilic polymer compound are mixed to form a coating film of the hydrophilic polymer compound on the surface of the outer shell of the heat storage microcapsule. Coated film heat storage microcapsules are produced. As a result, a film made of a hydrophilic polymer compound having excellent flexibility, film-forming properties, and gas barrier properties is formed on substantially the entire surface of the outer shell of the heat storage microcapsule. A dispersion containing capsules can be produced.
Next, in the second coating step, the dispersion containing the coating heat storage microcapsules generated in the first coating step and a phenol resin are mixed to produce a mixed dispersion, and the mixed dispersion is spray-dried to form a coating. A coated heat storage microcapsule powder in which a coating portion formed by adhering a phenol resin to at least a part of the surface of the coating film of the heat storage microcapsule is manufactured. As a result, a coated heat storage microcapsule powder in which a phenol resin having excellent solvent resistance and water resistance is attached to at least a part of the surface of the film of the film heat storage microcapsule can be obtained.
That is, a coated heat storage microcapsule powder comprising a coating portion in which a coating of a hydrophilic polymer compound is formed on the surface of the outer shell of the heat storage microcapsule, and a phenol resin is adhered and formed on at least a part of the surface of the coating You can get a body.

Specifically, for example, as shown in FIG. 1, in the first coating step, the capsule dispersion 3 a including the heat storage microcapsules 3 and the hydrophilic polymer compound 5 are mixed to form a capsule mixture 3 b. In the capsule heat storage microcapsule 3A in the capsule dispersion 3b, the hydrophilic polymer compound 5 (polyvinyl alcohol) is uniformly coated (coated) over substantially the entire surface of the outer shell 2.
Thereafter, for example, as shown in FIG. 2, in the second coating step, the capsule dispersion 3b and the aqueous solution of the phenol resin 6 are mixed to form a mixed dispersion 3c, and the mixed dispersion 3c is spray-dried. Provided on the surface of the outer shell 2 is a coating made of a hydrophilic polymer compound 5 that covers substantially the entire surface of the outer shell 2, and a coating portion 7 in which a phenol resin 6 is attached to at least a part of the surface of the coating. The coated heat storage microcapsule powder 4 composed of a plurality of coated heat storage microcapsules 3B can be obtained. The coated thermal storage microcapsule powder 4 is an aggregate in which a plurality of coated thermal storage microcapsules 3B are aggregated by the phenol resin 6 of the coating portion 7 of the coated thermal storage microcapsule 3B functioning as a binder during spray drying. It is in powder form. And the coating | coated part 7 which consists of the hydrophilic high molecular compound 5 and the phenol resin 6 exists in the whole surface or a part of this aggregate | assembly. In other words, the covering portion 7 exists between the adjacent ones of the plurality of aggregates, and the gaps and spaces generated between the adjacent ones of the aggregates are reduced by the covering portion 7.

Therefore, the coated heat storage microcapsule powder is entirely or partially coated with the hydrophilic polymer compound and phenol resin constituting the coating portion, and the adjacent coated heat storage microcapsules are covered with the phenol resin of the coating portion. Since they are combined to form an aggregate, the gaps and spaces between adjacent aggregates are reduced and relatively tightly coupled, and even if an organic solvent or the like enters, it is blocked by the covering portion. Direct contact with the surface of the outer shell is difficult.
Therefore, the coating part formed on the surface of the coated heat storage microcapsule powder can have excellent flexibility, film forming property, gas barrier property, solvent resistance and water resistance, especially for absorption and release of latent heat. In addition, it has the strength to withstand the expansion and contraction that accompanies it. In addition, it can prevent the organic solvent from coming into direct contact with the surface of the outer shell even under conditions where the organic solvent is present, and prevent the leakage of phase change substances. It is possible to stably produce a coated thermal storage microcapsule.

  The further characteristic means of the manufacturing method of the coated heat storage microcapsule according to the present invention is that the hydrophilic polymer compound is polyvinyl alcohol.

  According to this feature means, the hydrophilic polymer compound contains a large amount of hydroxyl groups in the hydrophilic polymer compound and also contains polyvinyl alcohol, which is a thermoplastic resin. It can be even higher. Further, even when the phase change material expands / contracts due to a temperature change, the polyvinyl alcohol can follow the expansion / contraction to prevent the outer shell from being destroyed and the phase change material to leak out better.

  The further characteristic means of the manufacturing method of the covering thermal storage microcapsule which concerns on this invention is the said hydrophilic in the ratio of 0.5 mass% or more and 15.0 mass% or less with respect to the said thermal storage microcapsule in the said 1st coating process. It is in the point which mixes a high molecular compound.

According to the present characteristic means, the mixing ratio of the hydrophilic polymer compound to the heat storage microcapsule is in the range of 0.5% by mass or more and 15.0% by mass or less in terms of the solid content ratio. While preventing a decrease in the amount of heat stored per unit mass of the heat storage microcapsule, it is possible to reliably form the coating portion and prevent a decrease in solvent resistance and water resistance.
When the ratio exceeds 15.0% by mass, the hydrophilic polymer compound covers the surface of the outer shell of the thermal storage microcapsule thickly, resulting in a decrease in thermal conductivity and excessive curing of the outer shell surface. In addition, there is a risk that the amount of heat stored per unit mass of the coated heat storage microcapsule powder may be reduced. On the other hand, when it is less than 0.5% by mass, the surface of the outer shell of the heat storage microcapsule is sufficient. It may be difficult to form a film, and solvent resistance and water resistance may be reduced.

  Further characteristic means of the method for producing a coated heat storage microcapsule according to the present invention is that the phenol resin is a phenol resin aqueous solution, and the viscosity of the phenol resin aqueous solution is in the range of 1 mPa · s to 2000 mPa · s, More preferably, it is in the range of 1 mPa · s or more and 1200 mPa · s or less, and more preferably 1 mPa · s or more and 1000 mPa · s or less.

According to the present feature means, since the phenol resin is a phenol resin aqueous solution, it can be easily mixed into the dispersion, and can be uniformly coated or dispersed on the surface of the film of the film heat storage microcapsule.
In addition, the viscosity of the aqueous phenol resin solution is in the range of 1 mPa · s to 2000 mPa · s, which is relatively low in viscosity, and its operation is unknown, but in the [tetrahydrofuran (THF) immersion test] described later. As will be explained, it is considered that phenolic resin can be uniformly coated or dispersed on the surface of the coating film of the heat storage microcapsule, thereby improving the tetrahydrofuran resistance (solvent resistance) of the coated heat storage microcapsule powder. .
If the viscosity exceeds 2000 mPa · s, there is a risk that the phenol resin adhering to the surface of the film of the film heat storage microcapsule will be excessively distributed in the second coating step, and that the spray nozzle (not shown) Since the possibility that the spray holes are blocked increases, it is not preferable. For the same reason, it is more preferable that the viscosity does not exceed 1200 mPa · s, and further more preferable not to exceed 1000 mPa · s.

  A further characteristic means of the method for producing a heat storage microcapsule according to the present invention is that, in the production of the mixed dispersion in the second coating step, 0.1% by mass or more and 3.0% by mass with respect to the film heat storage microcapsule. It is in the point which mixes the said phenol resin by the ratio of% or less, More preferably, it exists in the point which mixes a phenol resin by the ratio of 0.1 to 0.9 mass%.

According to this characteristic means, since the mixing ratio of the phenol resin to the film heat storage microcapsule is in the range of 0.1% by mass or more and 3.0% by mass or less in terms of solid content, the thermal conductivity is reduced and the film is coated. While preventing a decrease in the amount of heat stored per unit mass of the heat storage microcapsule, it is possible to reliably form a coating portion made of a hydrophilic polymer compound and a phenol resin to prevent a decrease in solvent resistance.
When the mixing ratio exceeds 3.0% by mass, the phenolic resin covers the surface of the coating film of the heat storage microcapsule thickly, which may cause a decrease in thermal conductivity and excessive curing of the coating surface. In addition, the heat storage amount per unit mass of the coated heat storage microcapsule powder may be reduced. On the other hand, when it is less than 0.1% by mass, the surface of the outer shell of the heat storage microcapsule has sufficient hydrophilicity. It may be difficult to form a covering portion made of a molecular compound and a phenol resin, and solvent resistance may be reduced.

  In order to achieve the above object, the characteristic means of the method for manufacturing a heat storage material according to the present invention is the coated heat storage microcapsule powder manufactured by the method for manufacturing a coated heat storage microcapsule according to any one of the above characteristic means. And a molding binder containing a phenol resin are mixed, molded into granules, and provided with a heat storage material granulation step for generating a granulated heat storage material.

According to this characteristic means, in the heat storage material granulation step, when the coated heat storage microcapsule powder provided with the coating portion and the molding binder containing the phenol resin are mixed, the coated heat storage microcapsule includes the surface of the outer shell. In addition to a coating made of a hydrophilic polymer compound formed on substantially the entire surface of the coating, a coating portion in which a phenol resin is attached to at least a part of the surface of the coating is already formed. And phenol resin as a molding binder can be mixed smoothly and satisfactorily. That is, as described later in [Observation test of mixing state at the time of addition of molding binder in heat storage material granulation step], both the covering portion and the molding binder are configured to contain a phenol resin, The coated heat storage microcapsule powder and the molding binder can be mixed in a well-familiar state, and good mixing in a quick and uniform mixed state can be realized. On the other hand, if a phenol resin is not present in the coating portion of the coated heat storage microcapsule powder and only polyvinyl alcohol (an example of a hydrophilic polymer compound) is present, the phenol resin is used as a molding binder. When mixing and granulating the granulated heat storage material, the coated heat storage microcapsule powder and the phenol resin become relatively large dumplings (so-called “dama”), and subsequent mixing becomes difficult or impossible. .
Therefore, the mixing state at the time of mixing the coated heat storage microcapsule powder and the molding binder containing the phenol resin can be made smooth and satisfactory.

  In addition, in the heat storage material granulation process, the coated heat storage microcapsule powder provided with the coating portion and the molding binder containing the phenol resin are mixed and molded into a granule to produce a granulated heat storage material. In this case, it is possible to maintain a state in which the phenolic resin of the covering portion and the phenolic resin as the molding binder are loosely bonded. For example, by using an extrusion molding machine, the coated heat storage microcapsule powder and the molding binder can be maintained. Even when the mixture is extruded, it is possible to satisfactorily prevent the extruded mixture from being broken or broken due to its own weight. Therefore, the granulation of the granulated heat storage material can be performed reliably and satisfactorily. That is, as will be described later in [Observation test of molding state in heat storage material granulation step], since both the coating portion and the molding binder include a phenol resin, the coated heat storage microcapsule powder And molding and granulation can be performed smoothly and satisfactorily in a state in which the binder for molding is well adapted. On the other hand, suppose that if the coating part in the coated heat storage microcapsule powder does not have phenol resin and only polyvinyl alcohol is present, and attempts to mold and granulate using phenol resin as a molding binder, for example, When the mixture of the heat storage microcapsule powder and the molding binder is extruded, the extruded mixture is easily cut by its own weight, making molding and granulation difficult or impossible.

As a result, the coating portion formed on the surface of the outer shell of the heat storage microcapsule has improved performance so as to have excellent flexibility, film forming property and gas barrier property by providing a coating with a hydrophilic polymer compound. In addition, the phenolic resin adheres to at least a part of the surface of the coating in the covering portion, so that the mixing property and molding when the coated microcapsule powder is mixed with the phenolic resin that is a molding binder The heat storage performance of the granulated heat storage material obtained as a result can be improved reliably.
Therefore, it is possible to quickly and reliably mix the coated heat storage microcapsule powder and the phenolic resin-containing molding binder to achieve a smooth and good mixing state, and to reliably mold and granulate the granulated heat storage material. It can be carried out.

  A further characteristic means of the method for producing a heat storage material according to the present invention is to provide a coated granulated heat storage material having a coating layer formed by coating the outer peripheral surface portion of the granulated heat storage material with a coating binder containing a phenol resin. It is in the point provided with the coating process to produce.

  According to this characteristic means, in the coating step, the outer peripheral surface portion of the granulated heat storage material molded with the molding binder is coated with the coating binder made of a phenol resin, and the coated granulation heat storage material is formed with the coating layer. Therefore, even if an organic solvent or moisture comes into contact with the coated granulated thermal storage material, the coating layer prevents the organic solvent or moisture from entering the coated granulated thermal storage material, The destruction of the outer shell can be prevented. In particular, since the molding binder contains a phenolic resin and the coating binder also contains a phenolic resin, both binders are familiar and the coating layer can be formed more reliably.

  The further characteristic means of the manufacturing method of the heat storage material which concerns on this invention exists in the point provided with the heating process which heats the said coating granulation heat storage material at the temperature higher than the temperature in the said heat storage material granulation process.

According to this characteristic means, the heating step of heating the coated granulated heat storage material at a temperature (for example, 140 ° C. or more and 185 ° C. or less) higher than the temperature (for example, about 90 ° C. to 120 ° C.) in the heat storage material granulation step. As it is provided, the polymerization reaction of the binder for the coating containing the phenol resin constituting the coating layer is promoted to increase the degree of polymerization (decrease the pores), the coating layer can be densified, and the mechanical strength of the coating layer can be increased. While improving, it can exhibit high immersion resistance with respect to an organic solvent, and can prevent destruction of the outer shell of the coated heat storage microcapsule.
The heating temperature is set to 140 ° C. or higher in order to further promote the further polymerization reaction of the coating binder to eliminate the uncured portion, while the heating temperature is set to 185 ° C. or lower in the coated heat storage microcapsule. This is to suppress thermal decomposition of the coated thermal storage microcapsule due to the expanded phase change material and the inner pressure rising to destroy the outer shell. For the same reason, the heating temperature is more preferably set to 150 ° C. or higher and 180 ° C. or lower.

  In order to achieve the above object, the adsorbent with a heat storage function according to the present invention includes the granulated heat storage material manufactured by the method for manufacturing a heat storage material according to any one of the above characteristic means, and the adsorbent. It is in the point which mixes.

  According to this characteristic configuration, even if the adsorbent adsorbs / desorbs the object to be adsorbed to cause a temperature change, and the adsorption / desorption performance decreases, the heat storage material absorbs or releases the temperature change as latent heat. Therefore, the temperature change of the adsorbent can be suppressed, and the adsorption / desorption performance of the adsorbent can be prevented from being lowered.

Schematic diagram mainly showing the first coating step of the method of manufacturing the coated thermal storage microcapsule Schematic diagram mainly showing the second coating step of the method for manufacturing the coated thermal storage microcapsule Conceptual diagram showing the manufacturing process of granulated heat storage material Conceptual diagram showing the manufacturing process of coated granulated heat storage material Conceptual diagram showing the molding process of adsorbent with heat storage function

  A method for producing a coated heat storage microcapsule powder (an example of a coated heat storage microcapsule) and a method for producing a granulated heat storage material (an example of a heat storage material) according to the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the method for producing a coated thermal storage microcapsule powder includes a phase change material 1 that absorbs and releases latent heat in response to a temperature change inside an outer shell 2 made of a polymer compound. This is a method for producing a coated heat storage microcapsule powder 4 in which a covering portion 7 is formed on a heat storage microcapsule 3 that is enclosed.
More specifically, the capsule dispersion 3a (an example of the dispersion) containing the heat storage microcapsules 3 and the hydrophilic polymer compound 5 are mixed and allowed to stand for several hours to several days, and the outer shell of the heat storage microcapsules 3 is obtained. A heat storage microcapsule 3A having a first coating step for generating a film heat storage microcapsule 3A in which a film of the hydrophilic polymer compound 5 is formed on the surface of the film 2; The phenol dispersion 6 is mixed with the capsule dispersion 3b containing the mixture to produce a mixture dispersion 3c. The mixture dispersion 3c is spray-dried, and the phenol resin 6 is applied to at least a part of the surface of the film of the film heat storage microcapsule 3A. It is a manufacturing method of the coating thermal storage microcapsule powder 4 provided with the 2nd coating process which manufactures the coating thermal storage microcapsule powder 4 in which the coating | coated part 7 formed by adhering was formed. .

  Moreover, as shown in FIGS. 3-5, the manufacturing method of the granulation heat storage material which concerns on this invention is the coating heat storage microcapsule powder 4 manufactured by the manufacturing method of the coating heat storage microcapsule powder 4, and a phenol resin. The heat storage material granulation process which mixes with the molding binder 8 containing, shape | molds it in a granule, and produces | generates the granulation heat storage material 9 (refer FIG. 3), and the granulation heat storage material 9 with the binder 10 for a coating containing a phenol resin. A coating step for coating the outer peripheral surface portion of the substrate and generating a coated granulated heat storage material 12 (an example of the granulated heat storage material) on which the coating layer 11 is formed, and a heating step for heating the coated granulation heat storage material 12 ( 4).

  Furthermore, the manufacturing method of the adsorbent 14 with a heat storage function is a manufacturing method of the adsorbent 14 with a heat storage function formed by mixing the coated granulated heat storage material 12 and the adsorbent 13 as shown in FIG.

[Method for producing thermal storage microcapsules]
First, the manufacturing method of the covering thermal storage microcapsule powder 4 containing the thermal storage microcapsule 3 is demonstrated.

[Heat storage microcapsule 3]
As shown in FIG. 1, the heat storage microcapsule 3 is configured by a microcapsule formed by enclosing a phase change material 1 that absorbs and releases latent heat according to a temperature change in an outer shell 2 made of a polymer compound. The
The phase change material 1 is not particularly limited as long as it is a compound that absorbs and releases latent heat in accordance with the phase change, but the temperature at which the phase change occurs corresponding to the use of the adsorbent 14 with a heat storage function (for example, the melting point). The compound can be selected according to the freezing point, for example, an organic compound and an inorganic compound having a melting point of about −150 ° C. to 100 ° C., preferably about 0 ° C. to 60 ° C. for a canister (not shown). Consists of. Specific examples include straight-chain aliphatic hydrocarbons such as tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, eicosane, heikosan, docosan, natural wax, petroleum wax, LiNO ₃ .3H ₂ O, Na ₂ SO _4.・ Hydrates of inorganic compounds such as 10H ₂ O and Na ₂ HPO ₄ · 12H ₂ O, fatty acids such as capric acid and lauric acid, higher alcohols having 12 to 15 carbon atoms, ester compounds such as methyl palmitate, etc. Can be used. In addition, as a phase change, phase changes, such as between solid-liquid, can be illustrated.
The phase change material 1 may be used in combination of two or more compounds selected from the above. When two or more kinds of phase change materials 1 are used in combination, the difference in temperature causing the phase change of each phase change material 1 is about 0 ° C. to 100 ° C., preferably 0 ° C. to 15 ° C. for canisters. A combination is preferred.
Further, in order to prevent the supercooling phenomenon of the phase change material 1, a compound having a melting point higher than that of the phase change material 1 may be added as necessary.

  Then, a capsule dispersion liquid containing the heat storage microcapsules 3 using the phase change material 1 as a core material and microcapsules by a known method such as a coacervation method or an in-situ method (interface reaction method). Generate as 3a. For example, the phase change material 1 is emulsified in a medium using an emulsifier such as a surfactant, and an initial condensate (prepolymer) corresponding to a desired polymer compound (resin etc.) described later is added thereto, Capsule dispersion (slurry) of heat storage microcapsule 3 having outer shell (resin wall, etc.) 2 and having phase change material 1 enclosed in outer shell 2 by heating to about 70 ° C. and proceeding the polymerization reaction 3a can be prepared (see FIG. 1).

As the outer shell 2 of the heat storage microcapsule 3, a known polymer compound can be used without particular limitation. For example, formaldehyde-melamine resin, melamine resin, formaldehyde-urea resin, urea resin, urea-formaldehyde-polyacryl An acid copolymer, polystyrene, polyvinyl acetate, polyacrylonitrile, polyethylene, polybutyl methacrylate, gelatin and the like can be used. Preferably, a thermosetting resin, particularly a melamine resin is used.
The weight ratio of the outer shell of the heat storage microcapsule 3 to the phase change material 1 (outer shell: phase change material) is not particularly limited, but is usually about 40:60 to 5:95, preferably 30:70 to 10:90. Degree.
The average particle diameter of the heat storage microcapsule 3 can be selected as appropriate from the required heat storage amount and capsule strength, but it can prevent destruction of the heat storage microcapsule 3 while ensuring the desired heat storage performance. An average particle diameter of about tens of μm is preferable.

  The capsule dispersion liquid 3a containing the heat storage microcapsule 3 generated as described above and the hydrophilic polymer compound 5 are mixed, and the surface of the outer shell 2 of the heat storage microcapsule 3 is made of the hydrophilic polymer compound 5. The film thermal storage microcapsule 3A in which is formed is generated (first coating step). In the present embodiment, as shown in FIG. 1, the hydrophilic polymer compound 5 is first added to the capsule dispersion 3 a and allowed to stand for several hours to several days, and the surface of the outer shell 2 of the heat storage microcapsule 3 is left. A film of the hydrophilic polymer compound 5 is formed over substantially the entire surface, and a capsule dispersion liquid 3b including a film heat storage microcapsule 3A on which the film is formed is generated.

  As the hydrophilic polymer compound 5, in addition to known cationic polymer compounds and anionic polymer compounds, nonionic surfactants can be used, and nonionic interfaces such as polyvinyl alcohol and carboxymethylcellulose can be used. It is preferred to use an activator. In particular, it is preferable to use a polymer polyhydric alcohol among nonionic surfactants, and it is particularly preferable to use polyvinyl alcohol. As the hydrophilic polymer compound 5, it is preferable to use a liquid polymer compound. In this case, substantially the entire surface of the outer shell 2 of the heat storage microcapsule 3 can be easily and uniformly coated, and the capsule dispersion 3a Mixing with can be facilitated. These hydrophilic polymer compounds 5 may be used singly or in combination of two or more.

  The mixing ratio of the hydrophilic polymer compound 5 to the capsule dispersion 3a is in the range of 0.5% by mass or more and 15.0% by mass or less, more preferably 1. It shall be in the range of 0 mass% or more and 10.0 mass% or less. If the amount exceeds 15.0% by mass, the surface of the outer shell 2 of the heat storage microcapsule 3 may be thickly covered. On the other hand, if the amount is less than 0.5% by mass, the target solvent resistance may decrease. There is.

  Thereafter, an aqueous solution of the phenol resin 6 is mixed with the capsule dispersion liquid 3b including the film heat storage microcapsule 3A coated with the hydrophilic polymer compound 5 to produce a mixed dispersion liquid 3c, and the mixed dispersion liquid 3c is spray-dried. Then, the coated heat storage microcapsule powder 4 in which the coating portion 7 formed by attaching the phenol resin 6 to at least a part of the surface of the coating film of the coating heat storage microcapsule 3A is manufactured (second coating step). Thereby, a film of the hydrophilic polymer compound 5 is formed on the surface of the outer shell 2 of the heat storage microcapsule 3, and the phenol resin 6 is attached to at least a part of the film of the hydrophilic polymer compound 5. The adhesion of the phenolic resin 6 to the coating of the hydrophilic polymer compound 5 may cover the entire coating of the hydrophilic polymer compound 5, but for the purpose of easily and stably producing a granulated heat storage material, The state which covers a part may be sufficient.

As the phenol resin 6, a known phenol resin that functions as a binder (binder) can be used. These phenol resins may be used alone or in combination of two or more.
Moreover, as the phenol resin 6, it is preferable to use an aqueous solution of the phenol resin 6. In this case, the phenol resin 6 can be uniformly coated or dispersed on the surface of the coating film of the coating heat storage microcapsule 3A. Moreover, mixing with the dispersion liquid 3b containing the film thermal storage microcapsule 3A can be facilitated. As the aqueous solution of the phenol resin 6, a known aqueous phenol resin solution can be used. When the aqueous solution of the phenol resin 6 is used, the viscosity thereof is in the range of 1 mPa · s to 2000 mPa · s, more preferably 1 mPa · s to 1200 mPa · s, still more preferably 1 mPa · s to 1000 mPa · s, Preferably, it is in the range of 1 mPa · s to 10 mPa · s. When the viscosity exceeds 2000 mPa · s, there is a possibility that the uneven distribution of the phenol resin 6 adhering to the surface of the coating film of the coating heat storage microcapsule 3A becomes too large in the second coating step described later, and a spray nozzle (not shown) ) Is not preferable because it is likely to be clogged, and for the same reason, it is more preferable that the viscosity does not exceed 1200 mPa · s, and more preferable that it does not exceed 1000 mPa · s.

  The mixing ratio of the phenol resin 6 to the capsule dispersion 3a is in the range of 0.1% by mass to 3.0% by mass, more preferably 0.1% by mass to 0.9% by mass in terms of solid content. Within the range, more preferably within the range of 0.3 mass% or more and 0.7 mass% or less. If it exceeds 3, 0% by mass, the phenolic resin 6 may cover the surface of the coating film of the thermal storage microcapsule 3A thickly, leading to a decrease in thermal conductivity and excessive curing of the coating surface. There is a possibility that the amount of heat stored per unit mass of the heat storage microcapsule powder 4 may be reduced. On the other hand, if the amount is less than 0.1% by mass, sufficient hydrophilic polymer compound on the surface of the outer shell 2 of the heat storage microcapsule 3 It is difficult to form the covering portion 7 made of 5 and the phenol resin 6, and the solvent resistance may be lowered.

  As shown in FIG. 1, in the first coating step, the film heat storage microcapsule 3A in the capsule dispersion 3b is, for example, the capsule dispersion 3a including the heat storage microcapsule 3 and the hydrophilic polymer in the first coating step. By mixing the compound 5 with the capsule mixed solution 3b, the coating film heat storage microcapsule 3A in the capsule dispersion 3b has the hydrophilic polymer compound 5 (polyvinyl alcohol) almost entirely on the surface of the outer shell 2. It has a form in which it is uniformly coated (coated). In this case, as described above, since the mixing ratio of the hydrophilic polymer compound 5 is appropriately set, the thickness of the coating film is substantially uniform.

As shown in FIG. 2, in the second coating step, the capsule dispersion 3b and the aqueous solution of the phenol resin 6 are mixed to form a mixed dispersion 3c, and the mixed dispersion 3c is spray-dried to thereby form the outer shell 2 A plurality of coating heat storages provided with a coating made of a hydrophilic polymer compound 5 covering substantially the entire surface of the outer shell 2 on the surface, and a coating portion 7 having a phenol resin 6 attached to at least a part of the surface of the coating The coated heat storage microcapsule powder 4 composed of the microcapsules 3B can be obtained. At this time, the spray drying is performed by spray drying at a predetermined temperature with a known spray drying device (not shown) to generate the heat storage microcapsule powder 4.
The coated thermal storage microcapsule powder 4 is an aggregate in which a plurality of coated thermal storage microcapsules 3B are aggregated by the phenol resin 6 of the coating portion 7 of the coated thermal storage microcapsule 3B functioning as a binder during spray drying. It is in powder form. And the coating | coated part 7 which consists of the hydrophilic high molecular compound 5 and the phenol resin 6 exists in the whole surface or a part of this aggregate | assembly. In other words, the covering portion 7 exists between the adjacent ones of the plurality of aggregates, and the gaps and spaces generated between the adjacent ones of the aggregates are reduced by the covering portion 7.
Specifically, as shown in FIG. 2, the coated heat storage microcapsule powder 4 is entirely or partially coated with the hydrophilic polymer compound 5 and the phenol resin 6 constituting the coating portion 7, and the coating Since the adjacent coated heat storage microcapsules 3B are joined together by the phenol resin 6 of the part 7 to form an aggregate, the gaps and spaces between the adjacent aggregates are reduced and relatively tightly coupled. Even if an organic solvent or the like enters, it is difficult to directly contact the surface of the outer shell 2 by being blocked by the covering portion 7.
Therefore, the coating part 7 formed on the surface of the coated heat storage microcapsule powder 4 can have excellent flexibility, film forming property, gas barrier property, solvent resistance and water resistance, and in particular, absorption of latent heat and It has the strength to withstand the expansion and contraction associated with the release, and it can well prevent the organic solvent from coming into direct contact with the surface of the outer shell 2 even under the condition where the organic solvent is present. The coated heat storage microcapsule powder 4 that can be satisfactorily prevented can be stably produced.

[Production method of granulated heat storage material]
Next, the heat storage material granulation step of further mixing the coated heat storage microcapsule powder 4 and the molding binder 8 containing the phenol resin and forming the granulated heat storage material 9 into a granule, and the phenol resin A coating step for coating the outer peripheral surface portion of the granulated heat storage material 9 with the coating binder 10 to generate a coated granulation heat storage material 12 on which the coating layer 11 is formed, and a heating step for heating the coated granulation heat storage material 12 The manufacturing method of the granulation heat storage material provided with these is demonstrated.

[Granulated heat storage material 9]
In the heat storage material granulation step, as shown in FIG. 3, the coated heat storage microcapsule powder 4 is provided with a relatively small amount of a phenol resin as a molding binder 8 (if necessary, a solvent such as water is also used. Addition) is added, mixed, kneaded, and molded, granulated, and dried (for example, about 90 ° C.) by a known extrusion molding machine to produce a granular granulated heat storage material 9.
Here, although details will be described later, when the coated heat storage microcapsule powder 4 provided with the coating portion 7 and the molding binder 8 containing phenol resin are mixed, in the present invention, the coated heat storage microcapsule 3A includes In addition to the coating made of the hydrophilic polymer compound 5 formed on substantially the entire surface of the shell 2, a covering portion 7 in which the phenol resin 6 is attached to at least a part of the surface of the coating is already formed. Therefore, mixing of the coated heat storage microcapsule powder 4 and the phenol resin as the molding binder 8 can be performed smoothly and satisfactorily.

  Although details will be described later, since the coated heat storage microcapsule powder 4 provided with the coating portion 7 and the molding binder 8 containing phenol resin are mixed and molded into granules, the granulated heat storage material 9 is generated. In this molding, the state in which the phenol resin 6 of the covering portion 7 and the phenol resin as the molding binder 8 are gently bonded can be maintained, and the coating is performed by an extrusion molding machine (not shown). Even when the mixture of the heat storage microcapsule powder 4 and the molding binder 8 is extruded, the extruded mixture can be satisfactorily prevented from being broken or broken due to its own weight. Granulation can be performed reliably and satisfactorily.

As the relatively small predetermined amount, 1 to 20% by mass of the molding binder 8 can be mixed with the coated heat storage microcapsule powder 4. If the amount is less than 1% by mass, the strength of the granulated heat storage material 9 is reduced, and when the granulated heat storage material 9 is destroyed, the heat storage effect is reduced and the granulated heat storage material 9 is bonded by the molding binder 8. It is not preferable because voids are excessively generated between the coated thermal storage microcapsules 3B, and the density is lowered and the thermal storage effect per unit volume is decreased. When the mass is larger than 20% by mass, the amount of thermal storage microcapsules relative to the molding binder 8 is relative. This is not preferable because the heat storage amount decreases. In addition, for the same reason, the predetermined amount is preferably 3 to 18% by mass, and more preferably 5 to 15% by mass.
In this way, the granulated heat storage material 9 in which the amount of the molding binder 8 added is relatively small, as shown in the enlarged view of FIG. 3, the area around the contact portion between the plurality of coated heat storage microcapsules 3B is the molding binder. 8 are combined into a granular shape.
As the molding binder 8, a known phenol resin that functions as a binder can be used as long as it is the same type of phenol resin as the phenol resin 6 mixed in the second coating step, and a phenol resin aqueous solution is particularly preferable. Other resins that function as binders can also be added.
The shape of the granulated heat storage material 9 is not particularly limited, but can be molded into any shape such as pellets (columnar or spherical), disks, blocks, honeycombs, and the like. Further, the average particle diameter is not particularly limited, but can be generally selected from about 0.1 mm to 4 mm, preferably about 0.3 mm to 3.5 mm, more preferably about 0.5 mm to 3.0 mm.

[Coated granulation heat storage material 12]
In the coating process, as shown in FIG. 4, a known amount of phenol resin (necessary as a coating binder 10), which is a relatively small amount, is applied to the outer peripheral surface portion of the granular granulated heat storage material 9 using a known coating apparatus. According to the above, a solvent such as water is added) and sprayed to produce a coated granulated heat storage material 12 in which the coating layer 11 is formed. Therefore, once the outer shape of the granulated heat storage material 9 is formed with the molding binder 8 and the outer shape is reliably formed, the coating layer 11 can be formed on the outer peripheral surface portion of the granulation heat storage material 9. Even if the coating layer 11 is formed so as to completely cover the outer peripheral surface portion, the amount of the coating binder 10 can be relatively reduced, and the coating can be performed relatively easily.
As the predetermined amount which is a relatively small amount, 1 to 10% by weight of the coating binder 10 can be mixed with the granulated heat storage material 9, and if it is less than 1% by weight, the alcohol resistance and gasoline resistance are reduced. When the amount is more than 10% by mass, the amount of heat storage microcapsules with respect to the molding binder 8 and the coating binder 10 is relatively decreased, and the amount of heat storage is decreased, which is not preferable. In addition, for the same reason, the predetermined amount is preferably 1 to 8% by mass, and more preferably 2 to 6% by mass. Moreover, the film thickness of the coating layer 11 formed as described above is about 0.5 to 15 μm, and when it is less than 0.5 μm, the solvent resistance such as alcohol resistance is lowered, and when it exceeds 15 μm, the heat storage amount is reduced. A decrease occurs and is not preferable. For the same reason, it is preferably 1 to 10 μm, more preferably about 1 to 8 μm.
As the coating binder 10, as in the case of the molding binder 8, a known phenol resin that functions as a binder can be used as long as it is the same type of phenol resin 6 as the phenol resin 6 mixed in the second coating step. In particular, an aqueous phenol resin solution is preferable. Other resins that function as binders can also be added.

In the heating process, as shown in FIG. 4, the coating granulated heat storage material 12 is subjected to a heat treatment.
The heat treatment can be performed in a temperature range of 140 ° C. or more and 185 ° C. or less, and more preferably 150 ° C. or more and 180 ° C. or less. In addition, this temperature range is a temperature range higher than the temperature (for example, about 90 degreeC-120 degreeC) in a thermal storage material granulation process. Here, the heating temperature is set to 140 ° C. or higher in order to further advance the polymerization reaction of the coating binder 10 and eliminate the uncured portion, while the heating temperature is set to 185 ° C. or lower in the coated heat storage microcapsule powder 4. This is to suppress the thermal decomposition of the coated heat storage microcapsule 3B caused by the expansion of the phase change material 1 encapsulated in the coated heat storage microcapsule 3B forming the inner shell and the destruction of the outer shell 2. For the same reason, the heating temperature is more preferably set to 150 ° C. or higher and 180 ° C. or lower.
Thereby, even when the degree of polymerization of the coating binder 10 constituting the coating layer 11 is low, at least the polymerization reaction of the coating binder 10 is promoted, and the minute holes existing in the coating layer 11 are blocked. A denser coating layer 10 can be formed. The dense coating layer 11 has a high mechanical strength and exhibits an organic solvent, particularly high immersion resistance, and prevents the outer shell 2 of the coated heat storage microcapsule 3B constituting the coated heat storage microcapsule powder 4 from being broken. can do. In this heat treatment, not only the polymerization reaction of the coating binder 10 is promoted, but also the molding binder 8, the phenol resin 6 constituting the covering portion 7, and the outer shell 2 of the heat storage microcapsule 3 are constituted at the same time. Polymerization reaction of the polymer material 2 to be promoted can also be promoted, and each can have a denser structure.

[Method of manufacturing adsorbent with heat storage function]
The manufacturing method of the adsorbent 14 with a heat storage function formed by mixing the coated granulated heat storage material 12 and the adsorbent 13 will be described.

[Adsorbent 13]
The adsorbent 13 can be a known adsorbent capable of adsorbing gas or the like, and in the case of a canister, a known adsorbent capable of adsorbing a vaporized fuel such as gasoline can be used. For example, activated carbon, zeolite , Silica gel, alumina, titania, organometallic complexes (copper fumarate, copper terephthalate, copper cyclohexanedicarboxylate, etc.) or a mixture thereof can be used.
Gases and the like that are adsorbed by the adsorbent 13 include methane, methane-based gas (natural gas, digestion gas, etc.), ethane, propane, dimethyl ether, CO ₂ , hydrogen sulfide, oxygen, nitrogen, NO _x , SO _x , CO, acetylene, ethylene, ammonia, methanol, ethanol, water, chloroform, aldehyde, etc. are exemplified, but when the adsorbent 13 is filled in a canister case, gasoline, which is a transpiration fuel, It becomes a mixture of alcohol (ethanol etc.) and gasoline.
The adsorbent 13 may be obtained by pulverizing activated carbon or the like, or may be used as a granular adsorbent 13 obtained by mixing the crushed material with a binder and molding it into granules. As this binder, the molding binder 8 can be used as in the case of the granulated heat storage material 9. In addition, the magnitude | size of the granular adsorbent 13 can be formed in the same magnitude | size and shape as the said granulated heat storage material 9. FIG.

[Adsorbent 14 with heat storage function]
The adsorbent 14 with a heat storage function is configured by mixing the coated granulated heat storage material 12 and the adsorbent 13, but the mixing method is not particularly limited. For example, the coated granulated heat storage material 12 and the granular adsorbent 13 may be mixed evenly. Further, as shown in FIG. 4, the adsorbent 14 with a heat storage function may be formed by mixing and granulating the coated granulated heat storage material 12 and the granular adsorbent 13 and then integrally forming the binder 15. As the binder 15, a known binder can be used, but it is preferable to use the same type of binder as the molding binder 8 (for example, an aqueous phenol resin solution). The shape of the formed adsorbent 14 with a heat storage function is not particularly limited. For example, the adsorbent 14 with a heat storage function can be molded into an arbitrary shape such as a pellet (columnar or spherical), a disk, a block, or a honeycomb. The average particle diameter is not particularly limited, but is usually about 0.5 mm to 4 mm, preferably about 0.5 mm to 3.6 mm, more preferably about 1 mm to 3 mm when used in a canister.

Hereinafter, this method will be specifically described with reference to examples.
Example 1
6.5 g of 37% formaldehyde aqueous solution and 10 g of water were added to 5 g of melamine powder and the pH was adjusted to 8, followed by heating to about 70 ° C. to obtain a melamine-formaldehyde initial condensate aqueous solution. While stirring 80 g of hexadecane as phase change material 1 in 100 g of sodium salt aqueous solution of styrene maleic anhydride copolymer adjusted to pH 4.5, the above melamine-formaldehyde initial condensate aqueous solution is vigorously stirred. After addition and emulsification, the pH was adjusted to 9 and encapsulation was performed. At this stage, a capsule dispersion liquid 3a including a heat storage microcapsule 3 in which hexadecane as the phase change material 1 was sealed inside the outer shell 2 made of melamine resin was obtained.
First, polyvinyl alcohol as the hydrophilic polymer compound 5 is added to the capsule dispersion liquid 3a at a solid content ratio of 1% by mass (the mass of the solid content of polyvinyl alcohol relative to the heat storage microcapsule 3 which is the solid content of the capsule dispersion liquid 3a). The capsule dispersion liquid 3b containing the film heat storage microcapsule 3A in which a polyvinyl alcohol film is formed over substantially the entire surface of the outer shell 2 of the heat storage microcapsule 3 is added and mixed at a ratio). Obtained (first coating step).
Thereafter, a phenol resin 6 (phenol resin aqueous solution) having a viscosity of 10 mPa · s (solid content at 25 ° C .: about 40% by mass) is added to the capsule dispersion 3b at a solid content ratio of 0.5% by mass (of the capsule dispersion 3b). The mixture dispersion liquid 3c was obtained by adding and mixing at a solid mass content of the phenol resin in the phenol resin aqueous solution with respect to the coating heat storage microcapsule 3A, which is a solid content (second coating step).
This mixed dispersion 3c is spray-dried under conditions of an intake temperature of 250 ° C. and an exhaust temperature of 105 ° C., and a coating made of polyvinyl alcohol covering the substantially entire surface of the outer shell 2 on the surface of the outer shell 2 made of melamine resin, and A coated heat storage microcapsule powder 4 composed of a plurality of coated heat storage microcapsules 3B provided with a coating portion 7 having a phenol resin 6 attached to at least a part of the surface of the coating was obtained (second coating step). The coated heat storage microcapsule powder 4 is an aggregate in which a plurality of coated heat storage microcapsules 3B are aggregated by the phenol resin 6 of the coating portion 7 of the coated heat storage microcapsule 3B functioning as a binder. .

(Example 2)
Example 1 except that in the second coating step, the viscosity of the phenol resin 6 added to the capsule dispersion liquid 3b containing the film heat storage microcapsules 3A was 1200 mPa · s (solid content at 25 ° C .: about 70% by mass). In the same manner as above, a coated heat storage microcapsule powder 4 including a plurality of coated heat storage microcapsules 3B on which the coating portion 7 was formed was obtained.

(Comparative Example 1)
The phenol resin 6 is added to the capsule dispersion liquid 3b including the film heat storage microcapsule 3A in which a polyvinyl alcohol film is formed over substantially the entire surface of the outer shell 2 of the heat storage microcapsule 3 obtained in the first coating step. Otherwise, a heat storage microcapsule powder in which a polyvinyl alcohol film was formed on the surface of the outer shell 2 made of melamine resin was obtained in the same manner as in Example 1 except that the capsule dispersion 3b was spray-dried.

The coated heat storage microcapsule powder 4 of Examples 1 and 2 is mixed with 10% by mass of a phenol resin (phenolic resin aqueous solution) as a molding binder 8 and formed into pellets having a diameter of 2 mm by an extrusion molding machine. A grain heat storage material 9 was obtained. After drying the granulated heat storage material 9 at 120 ° C., the granulated heat storage material 9 is coated with 4% by mass of a phenol resin (phenol resin aqueous solution) as a coating binder 10 dissolved in water and ethanol. A grain heat storage material 12 was obtained. These coating granulated heat storage materials 12 were heat-treated at 160 ° C. for 2 hours.
Similarly, the heat storage microcapsule powder of Comparative Example 1 was subjected to heat treatment by obtaining a granulated heat storage material, obtaining a coated granulation heat storage material.

[Tetrahydrofuran (THF) immersion test]
The coated heat storage microcapsule powder 4 according to Examples 1 and 2 obtained by the above method and the heat storage microcapsule powder according to Comparative Example 1 were immersed in a predetermined amount of tetrahydrofuran for 12 hours or more, and the filtrate was separated. A part of the filtrate was extracted, and the normal hexadecane content, which is a phase change substance, was measured with a gas chromatograph mass spectrometer (Shimadzu Corporation: model number GC2010 / GCMS-QP2010A). The results are listed in Table 1 below.
In addition, the normal hexadecane content (leakage amount) in Table 1 is the ratio of the leak weight of normal hexadecane to the weight of the heat storage microcapsule powder, and the numerical values in Table 1 are when the leak amount of Comparative Example 1 is 100 The ratio of the leakage amount of each of Examples 1 and 2 in FIG.

From this result, when the comparison of Example 1 and Comparative Example 1 and the comparison of Example 2 and Comparative Example 1 were performed, the polyvinyl alcohol was added to the outer shell 2 of the heat storage microcapsule 3 as in Examples 1 and 2. The coated heat storage microcapsule powder 4 in which a film is formed and the phenolic resin 6 is attached to at least a part of the surface of the film is formed on the outer shell 2 of the heat storage microcapsule 3 as in Comparative Example 1. It can be confirmed that the leakage amount of normal hexadecane is clearly smaller than that of the heat storage microcapsule powder in which only the alcohol film is formed.
Therefore, in the heat storage microcapsule powder 4 of Examples 1 and 2 according to the present invention, it was confirmed that the solvent resistance was improved.
Moreover, when the coated heat storage microcapsule powder 4 of Example 1 and Example 2 is compared, leakage of normal hexadecane is higher in Example 1 where the viscosity of the added phenol resin 6 is lower than in Example 2 where the viscosity is higher. It can be confirmed that the amount is obviously small. This is because the low-viscosity phenolic resin is likely to be uniformly coated or adhered to the polyvinyl alcohol coated on substantially the entire surface of the outer shell 2 of the heat storage microcapsule 3, so that the coating portion 7 is uniformly coated or adhered. This is thought to be due to the fact that it is adhered.
Therefore, it was confirmed that the solvent resistance was further improved by adding the phenol resin 6 having a low viscosity.

[Observation test of mixing state when adding binder 8 for molding in heat storage material granulation process]
10% by mass of phenol resin (phenol resin aqueous solution) as a molding binder 8 is added to each of the coated heat storage microcapsule powder 4 of Examples 1 and 2 and the heat storage microcapsule powder of Comparative Example 1, and after the addition The mixed state (particle size of the mixture) was observed. The results are listed in Table 2 below. The predetermined time is usually the time for completing the mixing of the powder, and this time is set to 10 minutes.

From this result, when adding and mixing the phenol resin as the molding binder 8 to the heat storage capsule powder in the heat storage material granulation step, the outer shell 2 of the heat storage microcapsule 3 as in Examples 1 and 2. The coated heat storage microcapsule powder 4 in which a film of polyvinyl alcohol is formed on the surface and the phenolic resin 6 is attached to at least a part of the surface of the film is more external to the heat storage microcapsule 3 as in Comparative Example 1. It can be confirmed that the heat storage microcapsule powder in which only the coating film of polyvinyl alcohol is formed on the shell 2 can be mixed more smoothly and satisfactorily and can be prevented from becoming difficult to mix.
That is, in Examples 1 and 2, since both the coating portion 7 and the molding binder 8 are configured to include a phenol resin, the coated heat storage microcapsule powder 4 and the molding binder 8 are in a well-familiar state. Mixing is possible, and good mixing can be realized in a quick and uniform mixing state. On the other hand, in Comparative Example 1, since the phenol resin is not present on the surface of the outer shell of the heat storage microcapsule and only the polyvinyl alcohol is present, it is mixed using the phenol resin as a molding binder. The microcapsule powder and the phenol resin are in a relatively large dumpling shape (so-called “dama”), and subsequent mixing is difficult or impossible.
Therefore, when adding the phenol resin as the molding binder 8 to the coated heat storage microcapsule powder 4 of Examples 1 and 2 according to the present invention to produce the granulated heat storage material 9, the coated heat storage microcapsule powder 4 It was confirmed that the coating part 7 containing the phenolic resin 6 can be reliably and satisfactorily mixed.

[Observation test of molding state in heat storage material granulation process]
A mixture obtained by adding 10% by mass of a phenol resin (phenol resin aqueous solution) as a molding binder 8 to each of the coated heat storage microcapsule powder 4 of Examples 1 and 2 and the heat storage microcapsule powder of Comparative Example 1, Molding and granulation were performed at a predetermined speed using an extrusion molding machine. The discharge rate of the mixture discharged from the molding port of the extrusion molding machine and the ease of cutting by the dead weight of the mixture were observed. The results are listed in Table 3 below.

As a result, in Example 1, since the mixture maintained a granular form of 2 to 3 mm from the powder form, it was smoothly discharged from the molding port and was hardly cut.
In Comparative Example 1, as compared with Example 1, the discharge speed from the molding port decreased, and the mixture was often cut when it was discharged from the molding port.
In Example 2, compared with Comparative Example 1, it was smoothly discharged from the molding port. There was little cutting by the weight of the molding.

Therefore, when adding the phenol resin as the molding binder 8 to the coated heat storage microcapsule powder 4 of Examples 1 and 2 according to the present invention to produce the granulated heat storage material 9, the coated heat storage microcapsule powder 4 Since the coating part 7 containing the phenolic resin 6 is present, molding and granulation can be performed reliably and satisfactorily.
That is, in Examples 1 and 2, since both the coating portion 7 and the molding binder 8 are configured to include a phenol resin, the coated heat storage microcapsule powder 4 and the molding binder 8 are in a well-familiar state. Molding and granulation can be performed smoothly and satisfactorily. On the other hand, in Comparative Example 1, when the phenolic resin is not present on the surface of the outer shell of the heat storage microcapsule and only the polyvinyl alcohol is present, molding and granulation are attempted using the phenolic resin as a molding binder. When the mixture of the heat storage microcapsule powder and the molding binder is extruded, the extruded mixture is easily cut by its own weight, making molding and granulation difficult or impossible.

[Cool thermal shock test]
The coating granulation heat storage material 12 subjected to the heat treatment in Examples 1 and 2 and the coating granulation heat storage material subjected to the heat treatment in Comparative Example 1 are repeatedly subjected to a heat history so as to straddle the phase change temperature. A treatment for causing the phase change between the phase and the solid phase a predetermined number of times was performed, and the weight retention after treatment (= mass after treatment / mass before treatment) was evaluated. The results are listed in Table 4 below.

As a result, the weight retention ratios of Examples 1 and 2 were larger values than the weight retention ratio of Comparative Example 1. Even when the thermal shock test was performed, the weight reduction was small.
This is because the coating part 7 containing the phenolic resin 6 is formed on the surface of the outer shell 2 of the thermal storage microcapsule 3 so that the coated thermal storage microcapsule powder 4 and the phenolic resin as the molding binder 8 in the thermal storage material granulation step. And the mixing in the coating granulation heat storage material 12 (granulation heat storage material 9) is reduced, and the stress change due to expansion and contraction of the heat storage microcapsule 3 due to thermal history can be effectively suppressed. Conceivable.
Therefore, the coating granulation heat storage material 12 of Examples 1 and 2 is considered to have improved water resistance, solvent resistance, and durability as compared with the coating granulation heat storage material of Comparative Example 1.

[Another embodiment]
(1) In the above embodiment, in the first coating step, the capsule dispersion liquid 3a including the heat storage microcapsule 3 is used to form a film of the hydrophilic polymer compound 5 on the surface of the outer shell 2 of the heat storage microcapsule 3. The capsule dispersion 3b mixed with the hydrophilic polymer compound 5 may be configured to generate powder of the heat storage microcapsule 3A in which a film is formed on the heat storage microcapsule 3 by spray drying. In the coating step, the mixed dispersion 3c can be generated by mixing the powder of the film heat storage microcapsule 3A and the dispersion medium, redispersing the film heat storage microcapsule 3A, and mixing with the phenol resin 6. .

(2) In the said embodiment, although the use of the coating granulation heat storage material 12 is not specifically limited, Especially the adsorption material 14 with the heat storage function which mixed the said coating granulation heat storage material 12 and the granular adsorbent 13 is used. It can also be used for a canister (not shown).
Here, the canister is generally used when a vehicle is stopped in order to prevent vaporized fuel (organic solvent) such as gasoline supplied to an internal combustion engine such as a vehicle from being released to the outside (such as in the atmosphere). In this case, excess vaporized fuel is adsorbed by the adsorbent in the case, and the air is introduced into the case as a purge gas during running, etc., and the adsorbed vaporized fuel is desorbed and supplied again to the internal combustion engine or the like. is there.
In a canister, since the adsorbent with a heat storage function filled in the case of the canister is in contact with a vaporized fuel such as gasoline and in contact with moisture contained in the atmosphere, the solvent resistance and water resistance against the vaporized fuel. Sex is required.

  The manufacturing method of the thermal storage microcapsule, the manufacturing method of the thermal storage material, and the adsorbent with the thermal storage function according to the present invention can be used as a technique that has high solvent resistance and water resistance and can reliably maintain the thermal storage performance.

1 Phase change material 2 Outer shell (polymer compound)
3 Thermal storage microcapsule 3A Film thermal storage microcapsule (thermal storage microcapsule)
3B coated thermal storage microcapsule (thermal storage microcapsule)
3a Capsule dispersion (dispersion)
3b Capsule dispersion (dispersion)
3c Mixed dispersion 4 Coated heat storage microcapsule powder 5 Hydrophilic polymer (coating)
6 Phenol resin 7 Covering part 8 Molding binder 9 Granulated heat storage material (heat storage material)
10 Coating Binder 11 Coating Layer 12 Coating Granulation Heat Storage Material (Granulation Heat Storage Material)
13 Adsorbent 14 Adsorbent with heat storage function 15 Binder

Claims (9)

A method for producing a coated thermal storage microcapsule in which a coating portion is formed on a thermal storage microcapsule in which a phase change material that absorbs and releases latent heat according to a temperature change is enclosed in an outer shell made of a polymer compound,
First, a dispersion containing the heat storage microcapsule and a hydrophilic polymer compound are mixed to produce a film heat storage microcapsule in which a coating of the hydrophilic polymer compound is formed on the surface of the outer shell of the heat storage microcapsule. A coating process;
A dispersion containing the film heat storage microcapsule and a phenol resin are mixed to form a mixed dispersion, the mixture dispersion is spray-dried, and the phenol is applied to at least a part of the surface of the film of the film heat storage microcapsule. A method for producing a coated heat storage microcapsule comprising: a second coating step for producing a coated heat storage microcapsule powder having a coating portion formed by adhering a resin.   The method for producing a coated heat storage microcapsule according to claim 1, wherein the hydrophilic polymer compound is polyvinyl alcohol.   3. The coated thermal storage micro of claim 1, wherein in the first coating step, the hydrophilic polymer compound is mixed at a ratio of 0.5 mass% to 15.0 mass% with respect to the thermal storage microcapsule. Capsule manufacturing method.   The said phenol resin is phenol resin aqueous solution, The viscosity of the said phenol resin aqueous solution exists in the range of 1 mPa * s or more and 2000 mPa * s or less, The manufacture of the coating thermal storage microcapsule as described in any one of Claims 1-3. Method.   The said phenol resin is mixed in the ratio of 0.1 to 3.0 mass% with respect to the said film thermal storage microcapsule in the case of the production | generation of the said mixed dispersion liquid in a said 2nd coating process. The manufacturing method of the coating thermal storage microcapsule as described in any one.   The coated heat storage microcapsule powder produced by the method for producing a coated heat storage microcapsule according to any one of claims 1 to 5 is mixed with a molding binder containing a phenol resin, and molded into a granule, The manufacturing method of the thermal storage material provided with the thermal storage material granulation process which produces | generates a granulated thermal storage material.   The heat storage material according to claim 6, further comprising a coating step of coating the outer peripheral surface portion of the granulated heat storage material with a coating binder containing a phenol resin to generate a coated granulation heat storage material in which a coating layer is formed. Production method.   The manufacturing method of the heat storage material of Claim 7 provided with the heating process which heats the said coating granulation heat storage material at the temperature higher than the temperature in the said heat storage material granulation process.   An adsorbent with a heat storage function obtained by mixing the granulated heat storage material manufactured by the method for manufacturing a heat storage material according to any one of claims 6 to 8 and an adsorbent.

Images