JP2010184981A - Heat storage rubber material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat storage rubber material obtained by kneading with microcapsules internally encapsulating a heat storage material and having the less reduction of heat storage function due to the leakage of the heat storage material which is the material encapsulated in the microcapsules, especially on being used repeatedly. <P>SOLUTION: By producing an olefin-based heat storage rubber material by the disclosed method, it is possible to provide the olefin-based heat storage rubber material obtained by kneading with the microcapsules internally encapsulating the heat storage material, and decreasing the reduction of the heat storage function due to the leakage of the heat storage material. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat storage rubber material containing microcapsules enclosing a latent heat storage material.

  In recent years, as comfort and energy-saving measures in the living environment have been demanded, architectural and civil engineering materials, air conditioning systems, interior materials such as vehicles, mechanical equipment, electrical and electronic equipment, cold and warm products, interior products such as curtains and carpets, In bedding, clothing goods, daily goods, etc., materials containing a latent heat storage material having a temperature control function and a constant temperature holding function have been proposed.

  A latent heat storage material capable of storing and releasing latent heat with a phase change between a liquid and a solid causes the latent heat storage material to flow out when liquid. To prevent this, it is used after taking measures such as putting it in a container. An example of the countermeasure is a microcapsule containing a latent heat storage material, and a heat storage resin composition or a heat storage rubber material containing the microcapsule has been proposed (see, for example, Patent Documents 1 to 5). A heat storage acrylic resin composition containing microcapsules enclosing a latent heat storage material and a heat storage sheet-like molded body using the same have also been proposed (see, for example, Patent Document 6). However, these heat storage rubber materials and the like have problems that the latent heat storage material leaks out (bleeds out) due to repeated use, and deterioration and shape change of the rubber material are observed.

JP 2005-23229 A JP 2003-261716 A JP-A-63-178191 No. 6-25914 JP 2000-314187 A JP 2007-31610 A

  In heat storage rubber materials kneaded with microcapsules containing latent heat storage materials, there is little leakage of latent heat storage materials, which are microcapsule inclusions, and there is little deterioration and shape change of rubber materials when used repeatedly. It is to provide a rubber material.

In order to solve the above problems, the inventors have found the following invention.
(1) In a heat storage rubber material containing a microcapsule containing a latent heat storage material, in a heat cycle test in which a cycle is held at -10 ° C, 10 minutes and 130 ° C, 10 minutes, A regenerative rubber material characterized by having a latent heat reproducibility after 500 cycles of 80% or more with respect to the latent heat amount of the regenerative rubber material.
(2) The heat storage rubber material according to the above (1), wherein the latent heat reproducibility of the heat storage component in the heat storage rubber material with respect to the latent heat amount of the microcapsules enclosing the latent heat storage material is 90% or more,
(3) The heat storage rubber material according to the above (1), wherein the rubber material is nitrile rubber, isoprene rubber or olefin rubber,
(4) The heat storage rubber material according to the above (1), wherein the resin constituting the microcapsule film is urea formalin resin or melamine formalin resin.

  ADVANTAGE OF THE INVENTION According to this invention, when repeatedly used, the heat storage rubber material which has few leakage of the latent heat storage material which is a microcapsule inclusion, and there is little deterioration of a rubber material and a shape change can be provided.

  The heat-storing rubber material of the present invention comprises a rubber material containing microcapsules enclosing a latent heat storage material. Rubber materials include natural rubber, isoprene rubber such as isoprene rubber, butadiene rubber such as styrene butadiene rubber and butadiene rubber, diene special rubber such as nitrile rubber, nitrile butadiene rubber, chloroprene rubber and hydrogenated nitrile rubber, ethylene Olefin rubber such as propylene rubber, ethylene propylene diene rubber, acrylic rubber, butyl rubber, halogenated butyl rubber, polyether rubber such as epichlorohydrin rubber and ethylene oxide-epichlorohydrin rubber, polysulfide rubber such as polysulfide rubber, polyester Polyurethane rubber such as urethane rubber, polyether urethane rubber, vinylidene fluoride rubber, fluorosilicone rubber, tetrafluoroethylene-propylene rubber, fluorophosphazene rubber, tetra Ruoroechiren - fluororubber such as perfluoro vinyl ether rubbers, polydimethyl silicone rubber, methyl vinyl silicone rubber, methylphenyl silicone rubber, silicone rubber such as fluorosilicone rubber. You may use these individually or in combination of 2 or more types. Among these, in order to obtain a heat storage rubber material with little leakage of the latent heat storage material that is contained in the microcapsule when repeatedly used, and less deterioration and shape change of the rubber material, nitrile rubber, isoprene rubber or olefin It is preferable to use a base rubber. In particular, it is particularly preferable to use ethylene-propylene diene rubber, which is a polyolefin-based rubber, because the latent heat reproducibility A described below can be further increased.

  In applications such as mechanical equipment and electrical / electronic equipment, it is generally disliked that an electrical contact failure or the like is caused by outgas generation derived from rubber or resin material used. For this reason, when a heat storage rubber material is used for these applications, it is preferable to use a rubber material other than silicone rubber because outgas is hardly generated.

  If necessary for the above rubber materials, vulcanizing agents, vulcanization accelerators, crosslinking agents, anti-aging agents, antioxidants, plasticizers, foaming agents, flame retardants, tackifiers, lubricants, peptizers (elementary) In addition to kneading accelerators, colorants, curing agents, foaming agents, dispersants, solvents, and the like, various fibers such as cotton, nylon, polyester, vinylon, glass, and carbon may be mixed.

  The microcapsules enclosing the latent heat storage material include an encapsulation method by a composite emulsion method (Japanese Patent Laid-Open No. 62-1452), a method of spraying a thermoplastic resin on the surface of the heat storage material particles (JP 62-45680), A method of forming a thermoplastic resin on the surface of the heat storage material particles in the liquid (JP-A-62-149334), a method of polymerizing and coating the monomer on the surface of the heat storage material particles (JP-A-62-2225241), interfacial polycondensation It can be produced by a method described in a process for producing a polyamide-coated microcapsule by reaction (Japanese Patent Laid-Open No. 2-258052).

  As microcapsule film, polystyrene, polyacrylonitrile, polyamide, polyacrylamide, ethylcellulose, polyurethane, aminoplast resin obtained by techniques such as interfacial polymerization method and in situ method, and coacervation of gelatin and carboxymethylcellulose or gum arabic Synthetic or natural resins using the method are used. In order to apply the heat storage material rubber material of the present invention, heat resistance is necessary, and in order to further increase the latent heat amount reproduction rate A described below, a microcapsule having a thermosetting resin film is preferable, In particular, a microcapsule using a urea formalin resin or a melamine formalin resin film by an in situ method is preferable.

  The latent heat storage material is appropriately selected according to the intended use. For example, a latent heat storage material having a melting point / freezing point of about 55 to 65 ° C. is selected if the temperature rise to 60 ° C. or higher is suppressed in applications such as mechanical equipment and electrical / electronic equipment. Examples of latent heat storage materials include paraffins, inorganic eutectics and inorganic hydrates, fatty acids such as docosanoic acid, aromatic hydrocarbon compounds such as benzene, ester compounds such as methyl octadecanoate, behenyl alcohol, polyethylene glycol, etc. Compounds such as alcohols are used, and chemically and physically stable compounds are used. Moreover, you may mix 2 or more types of latent heat storage materials from which melting | fusing point differs, and if necessary, a supercooling inhibitor, a specific gravity regulator, a deterioration inhibitor, etc. can be added.

  The average particle diameter of the microcapsules enclosing the latent heat storage material according to the present invention is preferably 10 μm or less, particularly preferably 5 μm or less, in order to prevent destruction due to physical pressure. The average particle size of the microcapsules is the type and concentration of the emulsifier, the temperature of the emulsified liquid during emulsification, the emulsification ratio (volume ratio of the water phase to the oil phase), the operation of the atomizer called emulsifier, disperser, etc. Conditions (such as the number of rotations of stirring, time, etc.) are adjusted as appropriate to set the desired average particle size. Exceeding this average particle diameter is not preferable because the microcapsules are easily broken by an external pressure, and are liable to float or settle when the specific gravity of the latent heat storage material is significantly different from that of the dispersion medium.

  In addition, the average particle diameter in this invention says a volume average particle diameter. The volume average particle diameter represents the average particle diameter of the microcapsule particles in terms of volume, and in principle, particles of a certain volume are sieved in order from the smallest, and the particles corresponding to 50% of the volume are separated. It means the particle size at the time. The volume average particle size can be measured by actual measurement by microscopic observation or the like, but can be automatically measured by using a commercially available electrical or optical particle size measuring device, and the dispersion liquid in the examples described later can be measured. The volume average particle diameter is measured using a particle size measuring device Coulter Multisizer II type manufactured by Beckman Coulter, USA.

  In general, microcapsules containing a latent heat storage material are obtained in a dispersion state. However, considering the ease of kneading with a rubber material and the heating process, the microcapsules are subjected to dehydration or drying, and the microcapsules are converted into solids, powders. Easy to use body and granule. The average particle size of the microcapsule powder is measured by using a laser diffraction particle size distribution measuring device. The average particle diameter of the solid or granulated microcapsule is represented by the average value of the length diameter measured with a measuring instrument such as calipers.

  In the thermal cycle test of the present invention, a heat storage rubber material is set in a thermal shock tester, and heat storage is performed under the heat cycle condition where -10 ° C, 10 minutes holding and 130 ° C, 10 minutes holding is one cycle. The heat storage material inside the microcapsule containing the heat storage material incorporated in the rubber material is melted and solidified for a plurality of cycles. Then, the latent heat amount (melting or coagulation heat amount) of the heat storage rubber material in the heat storage rubber material before and after the heat cycle test was measured using a differential scanning calorimeter (device name: DSC7, manufactured by PerkinElmer, USA) before the test. When the latent heat reproducibility A showing the ratio of the latent heat amount after 500 cycle tests to 80% or more is 80% or more, there is little leakage of the latent heat storage material that is the inclusion of microcapsules, and the deterioration and shape change of the rubber material Less. The latent heat reproduction rate A is more preferably 90% or more. The leakage of the latent heat storage material of the heat storage rubber material after the thermal cycle test and the deterioration and deformation of the rubber material are visually confirmed.

  In the present invention, the latent heat reproducibility B (%) of the heat storage rubber material with respect to the microcapsules containing the latent heat storage material for the heat storage rubber material includes the microcapsules and microcapsules containing the latent heat storage material. The amount of latent heat (melting or coagulation heat amount) per mass with the heat storage rubber material is measured using a differential scanning calorimeter (device name: DSC7, manufactured by PerkinElmer, USA), and determined by the formula 1 below.

  When the latent heat reproducibility B of the heat storage component in the heat storage rubber material with respect to the amount of latent heat of the microcapsule enclosing the latent heat storage material is 90% or more, the leakage of the latent heat storage material that is the microcapsule inclusion is small, Deterioration and shape change of rubber material are reduced.

  The heat storage rubber material of the present invention includes: 1. a process for preparing a microcapsule containing a latent heat storage material; 2. Mixing and molding a rubber material and microcapsules; In order to give rubber elasticity to a molded product to increase physical strength, it can be manufactured by a process of heating and crosslinking (vulcanization). Furthermore, the obtained heat storage rubber material can be used by cutting into a desired shape and size as required. Since these processes greatly affect the properties of the rubber material, the material used and the production method are selected according to the purpose of use.

  In step 2, a mixing device such as a commonly used mixer or kneader, such as a Banbury mixer or a kneader, can be used for mixing the microcapsules enclosing the latent heat storage material and the rubber material.

  The mixing time of the microcapsules enclosing the latent heat storage material and the rubber material is appropriately selected depending on the mixing apparatus and the mixing condition, but in order to further increase the latent heat reproduction rate A, the mixing time is preferably within 20 minutes. Within 6 minutes is more preferable.

  The pressure at the time of mixing is appropriately selected so that damage to the microcapsules is reduced in consideration of the mixing device and the mixing condition.

  The mixture of the microcapsules enclosing the latent heat storage material and the rubber material is molded using a mold or a molding machine, and subjected to a heating and crosslinking (vulcanization) process. The temperature of the heating / crosslinking (vulcanization) process varies depending on the type of rubber material, the crosslinking agent, whether or not a vulcanizing agent is added, and the type of additive. For example, when sulfur is added and vulcanized 40 to 200 ° C is preferable. In order to further increase the latent heat reproduction rate A, it is preferable to set the temperature to 160 ° C. or lower. Further, the heating / crosslinking (vulcanization) process time for increasing the latent heat amount reproduction rate A is preferably within 10 minutes, and more preferably within 5 minutes.

  When adding and kneading a solvent to the microcapsules enclosing the latent heat storage material and the rubber material, drying is performed as necessary to skip the solvent before performing the heating / crosslinking (vulcanization) step. For this solvent drying, an apparatus suitable for solvent drying such as a vacuum dryer or an explosion-proof dryer is used.

  The microcapsule content ratio in the heat storage rubber material of the present invention is preferably in the range of 10 to 90% by mass, and more preferably in the range of 30 to 70% by mass. When it exceeds 90% by mass, rubber elasticity and strength may be poor, and when it is less than 10% by mass, heat storage performance may be poor.

  Examples of the present invention will be described below, but the heat storage rubber material of the present invention can be applied without being limited only to these examples. Further, in the examples, percentages and parts without particular notice are based on mass.

Example 1
After adding 15.4 parts by mass of a 37% by mass aqueous formaldehyde solution and 40 parts by mass of water to 12 parts by mass of melamine powder, the pH was adjusted to 8, followed by heating to 70 ° C. to obtain an aqueous melamine-formaldehyde condensate aqueous solution. Stearyl stearate heated to 70 ° C. as a latent heat storage material while 100 parts by mass of sodium salt aqueous solution of 10% by mass styrene-maleic anhydride copolymer adjusted to pH 4.5 was heated to 70 ° C. (Product name: EXCEPARL SS, manufactured by Kao Corporation, melting point: 56 to 66 ° C.) 80 parts by mass were added with vigorous stirring, and emulsification was performed until the average particle size became 3.0 μm to obtain an emulsion. After adding the total amount of the above melamine-formaldehyde initial condensate aqueous solution to the obtained emulsion and stirring at 70 ° C. for 2 hours, the pH was raised to 9 and water was added to form a latent heat with a dry solid content concentration of 40%. A microcapsule dispersion 1 containing a heat storage material was obtained.

  This microcapsule dispersion 1 was dried with a spray dryer to a moisture content of 3% by mass or less to obtain a microcapsule powder 1 having an average particle size of 50 μm. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes with a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) was added, and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 92%, and the latent heat amount reproduction rate B was 91%.

  In addition, the latent heat amount reproduction rate A is set at −10 ° C. by setting a heat storage rubber material (5 cm × 5 cm) in a thermal shock tester (device name: small thermal shock device TSE-11, manufactured by Espec Corp.). Operate 500 cycles under the heat cycle condition where holding for 10 minutes, holding at 130 ° C. for 10 minutes is one cycle, and using a differential scanning calorimeter (device name: DSC7, manufactured by PerkinElmer, USA) Determined by measurement.

Example 2
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of isoprene rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) was added and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 92%, and the latent heat amount reproduction rate B was 93%.

Example 3
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of this microcapsule powder, 100 parts by mass of ethylene propylene diene rubber (EPDM) raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes in a closed kneader, a vulcanization accelerator ( Product name: Noxeller NS, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd. (3 parts by mass) was added and kneaded in the same manner for 3 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 95%, and the latent heat amount reproduction rate B was 97%.

Example 4
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a butyl rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS, 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) was added, and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 90%, and the latent heat amount reproduction rate B was 90%.

Example 5
7.5 parts by mass of urea is added to 125 parts by mass of an aqueous sodium salt solution of 5% by mass ethylene-maleic anhydride copolymer adjusted to pH 3.0, and heated to 70 ° C. 80 parts by mass of stearyl stearate (trade name: Exepal SS, manufactured by Kao Corporation, melting point 56-66 ° C.) heated to 70 ° C. as a latent heat storage material was added with vigorous stirring, and the average particle size was Emulsification was carried out to 3.0 μm to obtain an emulsion. To this emulsion, 19 parts of a 37% formaldehyde aqueous solution and 25 parts of water were added, followed by heating and stirring at 70 ° C. for 2 hours to carry out an encapsulation reaction. Then, the pH of the dispersion was adjusted to 9, and water was added. Thus, a microcapsule dispersion 2 containing a latent heat storage material having a dry solid content concentration of 40% was obtained.

  This microcapsule dispersion 2 was dried with a spray dryer to a moisture content of 3% by mass or less to obtain a microcapsule powder 2 having an average particle size of 50 μm. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes with a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) was added, and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 91%, and the latent heat amount reproduction rate B was 92%.

Example 6
The same microcapsule powder as in Example 1 was used. 100 parts by mass of the microcapsule powder and 100 parts by mass of polyol (trade name: Actol MN-3050: manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) and 1 part by mass of tin octylate as a catalyst are kneaded for 3 minutes in a closed kneader. Then, 50 parts by mass of tolylene diisocyanate (toluene-2,4-diisocyanate / toluene-2,6-diisocyanate = 80/20) was added and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Next, press heating was performed at a heating temperature of 90 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. About this heat storage rubber material, latent heat reproduction A was 80%, and latent heat reproduction B was 84%.

Example 7
As a latent heat storage material, stearyl stearate heated to 70 ° C. (trade name: Exepal SS, manufactured by Kao Corporation, melting point 56-66 ° C.) 34 parts by mass, methyl methacrylate 6 parts by mass and divinylbenzene 0.1 mass Part was dissolved. Next, 0.2 parts by mass of benzoyl peroxide was added, and the mixture was placed in a 0.5% by mass aqueous solution of partially saponified polyvinyl acetate heated to 70 ° C., and emulsified with vigorous stirring until the average particle size became 3.0 μm. To obtain an emulsion. The emulsion is placed in a polymerization vessel, subjected to a polymerization reaction at 80 ° C. for 7 hours in a nitrogen atmosphere, then the polymerization vessel is cooled to room temperature, water is added, and a latent heat storage material having a dry solid content concentration of 30% is added. To obtain a microcapsule dispersion 3.

  The microcapsule dispersion 3 was dried with a spray dryer to a moisture content of 3% by mass or less to obtain a microcapsule powder 3 having an average particle size of 50 μm. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes with a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) was added, and kneaded for 3 minutes in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed for 3 minutes at a heating temperature of 150 ° C. to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 80%, and the latent heat amount reproduction rate B was 85%.

Example 8
The same microcapsule powder as in Example 7 was used. 100 parts by mass of this microcapsule powder, 100 parts by mass of a polyol (trade name: Actol MN-3050, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) and 1 part by mass of tin octylate as a catalyst are kneaded for 1 minute in a closed kneader. After that, 50 parts by mass of tolylene diisocyanate (toluene-2,4-diisocyanate / toluene-2,6-diisocyanate = 80/20) was added and kneaded in the same manner for 1 minute to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press heating was performed for 3 minutes at a heating temperature of 90 ° C. to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 80%, and the latent heat amount reproduction rate B was 90%.

Example 9
A heat storage rubber material was obtained in the same manner as in Example 8, except that the same microcapsule powder as in Example 5 was used. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 83%, and the latent heat amount reproduction rate B was 91%.

Example 10
The same microcapsule powder as in Example 7 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 1 minute in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Co., Ltd.) were added and kneaded for 1 minute in the same manner to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed for 1 minute at a heating temperature of 150 ° C. to obtain a heat storage rubber material having a thickness of 1 mm. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 80%, and the latent heat amount reproduction rate B was 91%.

Example 11
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene are kneaded for 10 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Industry Co., Ltd.) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded product was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 160 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 89%, and the latent heat amount reproduction rate B was 90%.

Example 12
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene are kneaded for 10 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Industry Co., Ltd.) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Next, press vulcanization was carried out at a heating temperature of 160 ° C. for 15 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 85%, and the latent heat amount reproduction rate B was 87%.

Example 13
A heat storage rubber material was obtained in the same manner as in Example 2 except that the heating temperature during press vulcanization was set to 190 ° C. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 87%, and the latent heat amount reproduction rate B was 89%.

Example 14
A heat storage rubber material was obtained in the same manner as in Example 2 except that the heating time during press vulcanization was 15 minutes. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 85%, and the latent heat amount reproduction rate B was 88%.

Example 15
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of this microcapsule powder, 100 parts by mass of ethylene propylene diene rubber (EPDM) raw material, 1 part by mass of powdered sulfur and 100 parts by mass of toluene were kneaded for 10 minutes in a closed kneader, a vulcanization accelerator ( Trade name: Noxeller NS, manufactured by Ouchi Shinsei Chemical Co., Ltd.) 3 parts by mass was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 190 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 83%, and the latent heat amount reproduction rate B was 88%.

Example 16
The same microcapsule powder as in Example 1 was used. After 105 parts by mass of this microcapsule powder, 100 parts by mass of ethylene propylene diene rubber (EPDM) raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene were kneaded for 3 minutes in a closed kneader, a vulcanization accelerator ( 3 parts by mass of a trade name: Noxeller NS, manufactured by Ouchi Shinsei Chemical Co., Ltd.) was added and kneaded in the same manner for 3 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Next, press vulcanization was carried out at a heating temperature of 190 ° C. for 15 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 87%, and the latent heat amount reproduction rate B was 87%.

Example 17
A heat storage rubber material was obtained in the same manner as in Example 4 except that the heating temperature during press vulcanization was set to 165 ° C. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 88%, and the latent heat amount reproduction rate B was 88%.

Example 18
A heat storage rubber material was obtained in the same manner as in Example 4 except that the kneading time in the closed kneader was 11 minutes each. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 88%, and the latent heat amount reproduction rate B was 89%.

Example 19
A heat storage rubber material was obtained in the same manner as in Example 4 except that the press time during press vulcanization was 11 minutes. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 88%, and the latent heat amount reproduction rate B was 88%.

Example 20
A heat storage rubber material was obtained in the same manner as in Example 4 except that the press time during press vulcanization was 10 minutes. For this heat storage rubber material, the latent heat amount reproduction rate A was 88%, and the latent heat amount reproduction rate B was 90%.

Comparative Example 1
The same microcapsule powder as in Example 1 was used. 100 parts by mass of the microcapsule powder, 100 parts by mass of a polyol (trade name: Actol MN-3050, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) and 1 part by mass of tin octylate as a catalyst are kneaded for 10 minutes in a closed kneader. Then, 50 parts by mass of tolylene diisocyanate (toluene-2,4-diisocyanate / toluene-2,6-diisocyanate = 80/20) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Next, press heating was performed at a heating temperature of 100 ° C. for 15 minutes to obtain a urethane heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 75%, and the latent heat amount reproduction rate B was 86%.

Comparative Example 2
The same microcapsule powder as in Example 5 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene are kneaded for 10 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Industry Co., Ltd.) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Next, press vulcanization was carried out at a heating temperature of 190 ° C. for 15 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to the heat storage rubber material, the latent heat amount reproduction rate A was 73%, and the latent heat amount reproduction rate B was 85%.

Comparative Example 3
The same microcapsule powder as in Example 7 was used. After 105 parts by mass of the microcapsule powder, 100 parts by mass of a nitrile rubber raw material, 1 part by mass of powdered sulfur, and 100 parts by mass of toluene are kneaded for 10 minutes in a closed kneader, a vulcanization accelerator (trade name: Noxeller NS 3 parts by mass of Ouchi Shinsei Chemical Industry Co., Ltd.) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press vulcanization was performed at a heating temperature of 190 ° C. for 5 minutes to obtain a heat storage rubber material having a thickness of 1 mm. With respect to this heat storage rubber material, the latent heat amount reproduction rate A was 77%, and the latent heat amount reproduction rate B was 85%.

Comparative Example 4
The same microcapsule powder as in Example 7 was used. 100 parts by mass of this microcapsule powder and 100 parts by mass of polyol (trade name: Actol MN-3050: manufactured by Mitsui Chemicals Polyurethane Co., Ltd.) and 1 part by mass of tin octylate as a catalyst were kneaded for 10 minutes in a closed kneader. Then, 50 parts by mass of tolylene diisocyanate (toluene-2,4-diisocyanate / toluene-2,6-diisocyanate = 80/20) was added and kneaded in the same manner for 10 minutes to obtain a kneaded product. The obtained kneaded material was set in a 20 cm × 20 cm mold and dried in a vacuum dryer at 60 ° C. for 12 hours to completely remove toluene. Subsequently, press heating was performed for 3 minutes at a heating temperature of 90 ° C. to obtain a heat storage rubber material having a thickness of 1 mm. Regarding this heat storage rubber material, the latent heat amount reproduction rate A was 78%, and the latent heat amount reproduction rate B was 90%.

  Table 1 shows the results of visually confirming the latent heat reproduction ratios A and B and the leakage and shape change of the heat storage material of the heat storage rubber material after the heat cycle test. Of the items of leakage of heat storage materials in Table 1, those with no leakage are indicated with ◎, those with very little leakage are indicated with ○, those with little leakage are indicated with Δ, and those with large leakage are indicated with ×. In addition, in the items of deformation and deterioration of the heat storage rubber material, those without deformation or deterioration are indicated by ◎, those with a little are indicated by ○, those with a little are indicated by Δ, and those with a large are indicated by ×.

  From Table 1, the heat storage rubber material of the example whose latent heat amount reproduction rate A is 80% or more was good without leakage or shape deformation of the heat storage material. On the other hand, in the heat storage rubber material of the comparative example in which the latent heat reproduction rate A is less than 80%, leakage of the heat storage material and deformation and deterioration of the heat storage rubber material were confirmed more than in the examples.

Claims (4)

  In a heat storage rubber material containing a microcapsule containing a latent heat storage material, a heat storage rubber before the test in a heat cycle test in which one cycle is held at -10 ° C, 10 minutes and 130 ° C, 10 minutes. A regenerative rubber material characterized in that the latent heat reproducibility after 500 cycles with respect to the latent heat amount of the material is 80% or more.   The heat storage rubber material according to claim 1, wherein a latent heat amount reproduction rate of the heat storage component in the heat storage rubber material with respect to the amount of latent heat of the microcapsule enclosing the latent heat storage material is 90% or more.   The heat storage rubber material according to claim 1, wherein the rubber material is nitrile rubber, isoprene rubber or olefin rubber.   The heat storage rubber material according to claim 1, wherein the resin constituting the film of the microcapsule is urea formalin resin or melamine formalin resin.