Resin particles, method for producing resin particles, molded article, automobile part, electronic device part, fiber

Abstract

Provided is a resin particle, a method for producing a resin particle, a molded article, an automobile component, an electronic device component, and a fiber, the resin particle being capable of molding a molded article exhibiting a tensile fracture strength equal to the extent of the tensile fracture strength of a resin contained in the resin particle. The resin particle of the present invention is a resin particle containing a microcapsule containing a heat accumulating material and a thermoplastic resin, the content of the heat accumulating material being 70% by mass or less relative to the total mass of the resin particle, and the capsule wall of the microcapsule containing at least one resin selected from the group consisting of polyurethaneurea, polyurethane, and polyurea.

Description

TECHNICAL FIELD

[0001] The present application relates to a resin particle, a method for producing a resin particle, a molded article, an automobile component, an electronic device component, and a fiber. BACKGROUND

[0002] From the viewpoint of protecting functional materials such as heat-accumulating materials, perfumes, dye curing agents, and pharmaceutical ingredients contained in microcapsules, there is a possibility of providing new values to users. In particular, microcapsules containing a phase change material (PCM) and functioning as heat-accumulating materials that store heat generated outside are attracting attention.

[0003] In recent years, attempts have been made to produce resin particles containing microcapsules containing heat-accumulating materials. In Patent Literature 1, specifically, particles of microcapsules containing heat-accumulating materials and having a capsule wall composed of melamine resin are disclosed. Also, in Patent Literature 2, a granulate obtained using microcapsules containing heat-accumulating materials and polyvinyl alcohol is disclosed.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Laid-Open No. 2019-137723

[0007] Patent Literature 2: Japanese Patent Application Laid-Open No. 2007-284517 SUMMARY

[0008] PROBLEMS TO BE SOLVED BY THE INVENTION

[0009] On the other hand, it is desirable that the tensile fracture strength of a molded article obtained using resin particles containing microcapsules containing heat-accumulating materials and resin is equal to the tensile fracture strength of the resin contained in the resin particles. In other words, it is desirable to provide resin particles that can be molded into a molded article exhibiting a tensile fracture strength equal to the extent of the tensile fracture strength of a molded article formed using the resin contained in the resin particles and not containing microcapsules containing heat-accumulating materials.

[0010] As a result of the present inventors and others evaluating the above-described properties using the particles described in Patent Literature 1 and the granulate described in Patent Literature 2, it was found that the above-described requirements were not sufficiently satisfied.

[0011] In view of the above-described actual situation, the present application aims to provide resin particles that can be molded into a molded article exhibiting a tensile fracture strength equal to the extent of the tensile fracture strength of the resin contained in the resin particles.

[0012] Also, the present application provides a resin particle manufacturing method, a molded article, an automobile component, an electronic device component, and a fiber.

[0013] Means for solving technical problems

[0014] As a result of intensive studies by the present inventors on the above problems, it has been found that the above problems can be solved by the following configuration.

[0015] (1) A resin particle comprising a microcapsule containing a heat storage material and a thermoplastic resin,

[0016] The content of the heat storage material is 70% by mass or less relative to the total mass of the resin particle,

[0017] The capsule wall of the microcapsule contains at least one resin selected from the group consisting of polyurethane urea, polyurethane, and polyurea.

[0018] (2) The resin particle according to (1), wherein

[0019] The capsule wall of the microcapsule contains polyurethane urea.

[0020] (3) The resin particle according to (1) or (2), wherein

[0021] The total content of the microcapsule and the thermoplastic resin is more than 90% by mass relative to the total mass of the resin particle.

[0022] (4) The resin particle according to any one of (1) to (3), wherein

[0023] The resin contained in the capsule wall of the microcapsule has a structure represented by the formula (Y) described later.

[0024] (5) The resin particle according to any one of (1) to (4), wherein

[0025] The resin contained in the capsule wall of the microcapsule is a resin obtained by reacting:

[0026] an aromatic or alicyclic diisocyanate;

[0027] a compound having 3 or more active hydrogen groups in one molecule; and

[0028] a polymethylene polyphenyl polyisocyanate.

[0029] (6) The resin particle according to (5), wherein

[0030] The compound having 3 or more active hydrogen groups in one molecule is a polyol having a molecular weight of 500 or less.

[0031] (7) The resin particle according to any one of (1) to (6), wherein

[0032] The resin contained in the capsule wall of the microcapsule is formed using:

[0033] an adduct of an aromatic or alicyclic diisocyanate and a compound having 3 or more active hydrogen groups in one molecule, that is, a polyisocyanate A having 3 or more functional groups; and

[0034] a polyisocyanate B selected from an aromatic diisocyanate and a polymethylene polyphenyl polyisocyanate.

[0035] (8) The resin particle according to any one of (1) to (7), wherein

[0036] The capsule wall of the microcapsule has a thermal decomposition temperature of 200°C or higher.

[0037] (9) The resin particle according to any one of (1) to (8), wherein

[0038] The capsule wall of the microcapsule has a thickness of 0.10 to 5.0 μm.

[0039] (10) The resin particle according to any one of (1) to (9), wherein

[0040] The microcapsule has an average inner diameter of 200 μm or less.

[0041] (11) The resin particle according to any one of (1) to (10), wherein

[0042] The thermoplastic resin has a melting point of 110°C or higher.

[0043] (12) The resin particle according to any one of (1) to (11), wherein

[0044] The thermoplastic resin is a non-water-soluble resin.

[0045] (13) A method for producing a resin particle, which is the method for producing the resin particle according to any one of (1) to (12), wherein

[0046] The thermoplastic resin is melt-kneaded in an extruder, the microcapsule is added to the melt of the thermoplastic resin in the extruder and further melt-kneaded, the strand extruded through the extruder is cut, and thereby the resin particle is produced.

[0047] (14) A molded article which is molded using the resin particle according to any one of (1) to (12).

[0048] (15) An automobile part molded using the resin particles described in any one of (1) to (12).

[0049] (16) An electronic device part molded using the resin particles described in any one of (1) to (12).

[0050] (17) A fiber molded using the resin particles described in any one of (1) to (12).

[0051] Effects of the Invention

[0052] According to the present application, it is possible to provide resin particles that enable molding of a molded article exhibiting a tensile fracture strength equal to the extent of the tensile fracture strength of the resin contained in the resin particles.

[0053] Further, according to the present application, it is possible to provide a method for producing resin particles, a molded article, an automobile part, an electronic device part, and a fiber. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 is a partial schematic view of an SEM image of a cross section of the resin particles. DETAILED DESCRIPTION

[0055] In the present specification, a numerical range represented by "~" indicates a range including the lower limit value and the upper limit value of the numerical values recited before and after the "~".

[0056] In the numerical ranges recited in stages in the present specification, the upper limit value or the lower limit value recited in a certain numerical range can be replaced with the upper limit value or the lower limit value of another numerical range recited in stages. Also, in the numerical ranges recited in the present specification, the upper limit value or the lower limit value recited in a certain numerical range can be replaced with the values shown in the examples.

[0057] The various components described later can be used singly or can be used in a mixture of two or more. For example, the polyisocyanate described later can be used singly or can be used in a mixture of two or more.

[0058] As a feature point of the resin particles of the present application, it can be cited that the capsule wall of the microcapsule contains a prescribed resin, and the content of the heat storage material is equal to or less than a prescribed value.

[0059] It was found that by selecting a prescribed resin as the material of the capsule wall of the microcapsule, the decrease in the tensile fracture strength was suppressed. Also, it was found that in the case where the content of the heat storage material was excessive, the tensile fracture strength of the obtained molded article decreased, and by setting the content to be equal to or less than a prescribed value, the decrease in the tensile fracture strength was suppressed.

[0060] The resin particle of the present application contains: a microcapsule containing a heat storage material (hereinafter, also simply referred to as "microcapsule"); and a thermoplastic resin.

[0061] Hereinafter, first, the components contained in the resin particle are described in detail.

[0062] <Microcapsule>

[0063] The microcapsule has a core portion and a capsule wall for containing a core material (a material to be contained (also referred to as a contained component)) forming the core portion.

[0064] The microcapsule contains a heat storage material as a core material (a contained component). Since the heat storage material is contained in the microcapsule, the heat storage material can stably exist in a phase state corresponding to the temperature.

[0065] (Heat storage material)

[0066] The kind of the heat storage material is not particularly limited, and a material that undergoes a phase change corresponding to a temperature change can be used, and a material that can repeatedly undergo a phase change between a solid phase and a liquid phase accompanying melting and solidification corresponding to a temperature change is preferable.

[0067] The phase change of the heat storage material is preferably based on a phase change temperature possessed by the heat storage material itself, and in the case of a phase change between a solid phase and a liquid phase, a melting point is preferable.

[0068] As the heat storage material, for example, any one of a material that can store heat generated outside a molded article manufactured using the resin particle as sensible heat, a material that can store heat generated outside a molded article manufactured using the resin particle as latent heat (hereinafter, also referred to as "latent heat storage material"), a material that undergoes a phase change accompanying a reversible chemical change, and the like can be used. The heat storage material is preferably a material that can release stored heat.

[0069] Among them, from the viewpoint of easiness of control of the amount of heat that can be accepted and the size of the heat, as the heat storage material, a latent heat storage material is preferable.

[0070] The latent heat storage material refers to a material that stores heat generated outside a molded article manufactured using the resin particle as latent heat. For example, it refers to a material that, in the case of a phase change between a solid phase and a liquid phase, repeatedly undergoes a change between melting and solidification at a melting point determined depending on the material as a phase change temperature, thereby performing heat acceptance and release based on latent heat.

[0071] In the case of a phase change between a solid phase and a liquid phase, the latent heat storage material can use the heat of fusion at the melting point and the heat of solidification at the solidification point to store or release heat accompanying a phase change between a solid and a liquid.

[0072] The types of latent heat storage materials are not particularly limited and can be selected from compounds with melting points that are capable of phase change.

[0073] Examples of materials that can be used for latent heat storage include, for example, ice (water); inorganic salts; aliphatic hydrocarbons such as paraffin (e.g., isoparaffins, n-alkanes); fatty acid esters such as tri(octanoic / capric)glycerides, methyl myristate (melting point 16–19°C), isopropyl myristate (melting point 167°C), and dibutyl phthalate (melting point -35°C); alkyl naphthalene compounds such as diisopropylnaphthalene (melting point 67–70°C); and 1-phenyl-1-xylylethane (melting point low). Aromatic hydrocarbons including diarylalkane compounds (melting point -50℃), alkylbiphenyl compounds such as 4-isopropylbiphenyl (melting point 11℃), triarylmethane compounds, alkylbenzene compounds, benzylnaphthalene compounds, diarylinyl alkyl compounds, and arylindane compounds; natural animal and vegetable oils such as camellia oil, soybean oil, corn oil, cottonseed oil, rapeseed oil, olive oil, coconut oil, castor oil, and fish oil; mineral oil; diethyl ethers; aliphatic diols; sugars; sugar alcohols, etc.

[0074] The phase change temperature of heat storage materials is not particularly limited, as long as it is appropriately selected in accordance with the type of heat-generating element, the heating temperature of the heat-generating element, the temperature after cooling or the holding temperature, and the cooling method.

[0075] The heat storage material is preferably selected from materials that have a phase change temperature (preferably melting point) in the target temperature region (e.g., the operating temperature of the heating element; hereinafter also referred to as the "thermal control region").

[0076] The phase change temperature of the heat storage material varies depending on the thermal control region, preferably 0–80°C, and more preferably 10–70°C.

[0077] From the viewpoint that molded articles made using resin particles have better heat storage properties, aliphatic hydrocarbons are preferred as latent heat storage materials, and paraffin wax is more preferred.

[0078] The melting point of aliphatic hydrocarbons (preferably paraffin) is not particularly limited, but from the viewpoint of suitability for various applications, it is preferably above 0°C, more preferably above 15°C, and even more preferably above 20°C. The upper limit is not particularly limited, but it is preferably below 80°C, more preferably below 70°C, even more preferably below 60°C, and particularly preferably below 50°C.

[0079] From the viewpoint that molded articles manufactured using resin particles have better heat storage properties, linear aliphatic hydrocarbons are preferred as aliphatic hydrocarbons. The number of carbon atoms in the linear aliphatic hydrocarbon is not particularly limited, but is preferably 14 or more, more preferably 16 or more, and even more preferably 17 or more. The upper limit is not particularly limited, but is preferably 30 or less, more preferably 28 or less, and even more preferably 26 or less.

[0080] As the aliphatic hydrocarbon, a straight-chain aliphatic hydrocarbon having a melting point of 0°C or higher is preferable, and a straight-chain aliphatic hydrocarbon having a melting point of 0°C or higher and a carbon number of 14 or more is more preferable.

[0081] As the straight-chain aliphatic hydrocarbon (straight-chain paraffin) having a melting point of 0°C or higher, for example, n-tetradecane (melting point 6°C), n-pentadecane (melting point 10°C), n-hexadecane (melting point 18°C), n-heptadecane (melting point 22°C), n-octadecane (melting point 28°C), n-nonadecane (melting point 32°C), n-eicosane (melting point 37°C), n- heneicosane (melting point 40°C), n-docosane (melting point 44°C), n-tricosane (melting point 48 to 50°C), n-tetracosane (melting point 52°C), n-pentacosane (melting point 53 to 56°C), n-hexacosane (melting point 57°C), n-heptacosane (melting point 60°C), n-octacosane (melting point 62°C), n-nonacosane (melting point 63 to 66°C), and n-triacontane (melting point 66°C) can be listed.

[0082] In the case where the straight-chain aliphatic hydrocarbon is used as the heat storage material, the content of the straight-chain aliphatic hydrocarbon is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, and particularly preferably 98% by mass or more, with respect to the content of the heat storage material. As the upper limit, 100% by mass can be listed.

[0083] As the inorganic salt, for example, an inorganic hydrated salt is preferable, and a hydrated compound of a chloride of an alkali metal (for example, sodium chloride 2 hydrate, etc.), a hydrated compound of an acetate of an alkali metal (for example, sodium acetate hydrate, etc.), a hydrated compound of an alkali metal sulfate (for example, sodium sulfate hydrate, etc.), a hydrated compound of a thiosulfate of an alkali metal (for example, sodium thiosulfate hydrate, etc.), a hydrated compound of an alkali earth metal sulfate (for example, calcium sulfate hydrate, etc.), and a hydrated compound of a chloride of an alkali earth metal (for example, calcium chloride hydrate, etc.) can be listed.

[0084] As the aliphatic diol, 1,6-hexanediol and 1,8-octanediol can be listed.

[0085] As the sugar and sugar alcohol, xylitol, erythritol, galactitol, and dihydroxyacetone can be listed.

[0086] The heat storage material can be used singly or in a mixture of two or more. By using one kind singly or using a plurality of heat storage materials having different melting points, the temperature region in which the heat storage property appears and the heat storage amount can be adjusted according to the use.

[0087] By mixing the heat storage material having a melting point at the center temperature at which the heat storage action of the heat storage material is to be obtained and the heat storage material having a melting point before and after the heat storage material, it is possible to expand the temperature region in which heat can be stored. By way of example, in the case where paraffin is used as the heat storage material, paraffin a having a melting point at the center temperature at which the heat storage action of the heat storage material is to be obtained is used as the center material, and paraffin a and other paraffins having a number of carbon atoms before and after paraffin a are mixed, whereby it is possible to design the molded product manufactured using the resin particles to have a wide temperature region (heat control region).

[0088] The content of the paraffin having a melting point at the center temperature at which the heat storage action is to be obtained is not particularly limited, but is preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more, and particularly preferably 98% by mass or more, with respect to the total mass of the heat storage material. As the upper limit, 100% by mass can be given.

[0089] In the case where paraffin is used as the heat storage material, one kind of paraffin can be used alone, or two or more kinds can be mixed and used. In the case where a plurality of paraffins having different melting points are used, it is possible to expand the temperature region in which heat storage is exhibited.

[0090] In the case where a plurality of paraffins are used, the content of the main paraffin is not particularly limited from the viewpoint of the temperature region in which heat storage is exhibited and the amount of heat storage, and is preferably 80 to 100% by mass, more preferably 90 to 100% by mass, and further preferably 95 to 100% by mass, with respect to the total mass of the paraffins.

[0091] In addition, the "main paraffin" refers to the paraffin having the largest content among the plurality of paraffins contained. The content of the main paraffin is preferably 50% by mass or more with respect to the total mass of the paraffins.

[0092] Furthermore, the content of the paraffin is not particularly limited, but is preferably 80 to 100% by mass, more preferably 90 to 100% by mass, and further preferably 95 to 100% by mass, and particularly preferably 98 to 100% by mass, with respect to the total mass of the heat storage material (preferably, latent heat storage material).

[0093] Furthermore, the paraffin is preferably a linear paraffin, and more preferably substantially contains no branched paraffin. This is because, by containing a linear paraffin and substantially containing no branched paraffin, the heat storage property is further improved. As a reason for this, it is presumed that the association of the molecules of the linear paraffin with each other is inhibited by the branched paraffin.

[0094] The content of the heat storage material in the resin particles is 70% by mass or less with respect to the total mass of the resin particles.

[0095] From the viewpoint that the tensile strength at break of the molded article obtained using the resin particles of the present application is more excellent (hereinafter, also referred to as "the viewpoint that the effect of the present application is more excellent"), it is preferable that the content of the heat storage material in the core material is 50% by mass or less, more preferably 40% by mass or less. The lower limit is not particularly limited, and from the viewpoint that the heat storage property of the molded article is more excellent, it is preferable that the content of the heat storage material is 10% by mass or more, more preferably 20% by mass or more.

[0096] The content of the heat storage material in the microcapsule is not particularly limited, and from the viewpoint of the heat storage property and the heat resistance of the microcapsule, it is preferable that the content of the heat storage material is 40 to 95% by mass, more preferably 60 to 85% by mass.

[0097] (Other components)

[0098] As the core material of the microcapsule, other components than the above-mentioned heat storage material can be contained. As the other components that can be contained in the microcapsule as the core material, for example, additives such as solvents, ultraviolet absorbers, light stabilizers, antioxidants, paraffin, deodorants, and flame retardants can be exemplified.

[0099] The content of the heat storage material in the core material is not particularly limited, and from the viewpoint that the heat storage property of the molded article manufactured using the resin particles is more excellent, it is preferable that the content of the heat storage material is 80 to 100% by mass, more preferably 90 to 100% by mass, with respect to the total mass of the core material.

[0100] The microcapsule can contain a solvent as the core material.

[0101] As the solvent in this case, the above-mentioned heat storage material whose melting point deviates from the temperature region (heat control region; for example, the operating temperature of a heat generating body) used in the molded article manufactured using the resin particles can be exemplified. That is, the solvent refers to a solvent that does not undergo phase transition in a liquid state in the heat control region, in distinction from the heat storage material that causes phase transition in the heat control region to generate an endothermic / exothermic reaction.

[0102] The content of the solvent in the core material is not particularly limited, but it is preferable that the content of the solvent is less than 30% by mass, more preferably less than 10% by mass, further preferably 1% by mass or less, with respect to the total mass of the core material. The lower limit is not particularly limited, and 0% by mass can be exemplified.

[0103] (Capsule wall (wall portion))

[0104] The microcapsule has a capsule wall that contains the core material.

[0105] The material that forms the capsule wall in the microcapsule can exemplify at least one resin selected from the group consisting of polyurethane urea, polyurethane, and polyurea. Among them, from the viewpoint that the effect of the present application is more excellent, it is preferable that the material is polyurethane urea.

[0106] Further, the polyurethane is a polymer having a plurality of urethane bonds, and is preferably a reaction product of a polyol and a polyisocyanate.

[0107] Further, the polyurethane is a polymer having a plurality of urethane bonds, and is preferably a reaction product of a polyol and a polyisocyanate.

[0108] Further, the polyurethane is a polymer having a plurality of urethane bonds, and is preferably a reaction product of a polyol and a polyisocyanate.

[0109] Further, in the case where the polyurethane urea is obtained by reacting the polyol and the polyisocyanate, a part of the polyisocyanate is reacted with water to become a polyamine, and the polyurethane urea can be obtained.

[0110] The capsule wall of the microcapsule preferably has urethane bonds. The capsule wall having urethane bonds can be obtained, for example, using the above-described polyurethane urea or polyurethane.

[0111] The urethane bond is a bond having high motility, and thus can impart thermoplasticity to the capsule wall. Further, the softness of the capsule wall can be easily adjusted. Therefore, it is difficult to hinder the properties of the resin in the resin particles, and it is easy to suppress the decrease in the tensile strength.

[0112] The polyurethane, the polyurea, and the polyurethane urea are preferably formed using a polyisocyanate.

[0113] The polyisocyanate is a compound having two or more isocyanate groups, and examples thereof include aromatic polyisocyanates and aliphatic polyisocyanates.

[0114] Examples of the aromatic polyisocyanate include m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, 3,3'-dimethoxy-biphenyl diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-diisocyanate, 4-chloroxylene-1,3-diisocyanate, 2-methylxylene-1,3-diisocyanate, 4,4'-diphenylpropane diisocyanate, and 4,4'-diphenylhexafluoropropane diisocyanate.

[0115] As the aliphatic polyisocyanate, for example, trimethylene diisocyanate, hexamethylene diisocyanate, propylene- 1, 2-diisocyanate, butylene- 1, 2-diisocyanate, cyclohexylene- 1, 2-diisocyanate, cyclohexylene- 1, 3-diisocyanate, cyclohexylene- 1, 4-diisocyanate, dicyclohexylmethane-4, 4'-diisocyanate, 1, 4-bis (isocyanatomethyl) cyclohexane, 1, 3-bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate, lysine diisocyanate, and hydrogenated xylene diisocyanate can be exemplified.

[0116] Further, the above-mentioned examples illustrate 2-functional aromatic polyisocyanates and aliphatic polyisocyanates, but as the polyisocyanate, 3-functional or more polyisocyanates (for example, 3-functional triisocyanates and 4-functional tetraisocyanates) can also be exemplified.

[0117] More specifically, as the polyisocyanate, the trimer of the above-mentioned 2-functional polyisocyanate, i.e., a buret body or isocyanurate body, an adduct of a polyol such as trimethylolpropane and a 2-functional polyisocyanate, a formalin adduct of benzisocyanurate, a polyisocyanate having a polymerizable group such as methacryloxyethyl isocyanate, and lysine triisocyanate can also be exemplified.

[0118] As for the polyisocyanate, it is described in "Polyurethane Resin Handbook" (edited by Keiji Iwata, published by NIKKAN KOGYO SHIMBUN, LTD. (1987)).

[0119] Among them, as the polyisocyanate, a 3-functional or more polyisocyanate is preferred.

[0120] As the 3-functional or more polyisocyanate, for example, a 3-functional or more aromatic polyisocyanate and a 3-functional or more aliphatic polyisocyanate can be exemplified.

[0121] As the 3-functional or more polyisocyanate, an adduct (addition product) of a 2-functional polyisocyanate and a compound having 3 or more active hydrogen groups in one molecule (for example, a 3-functional or more polyol, a polyamine, or a polythiol, etc.), i.e., a 3-functional or more polyisocyanate (adduct type 3-functional or more polyisocyanate) and a trimer of a 2-functional polyisocyanate (biuret type or isocyanurate type) are also preferred.

[0122] As the 3 or more functional polyisocyanate of the adduct type, for example, TAKENATE (registered trademark) D-102, D-103, D-103H, D-103M2, P49-75S, D-110N, D-120N, D-140N, D-160N (all of which are manufactured by Mitsui Chemicals, Inc.), Desmodur (registered trademark) L75, UL57SP (manufactured by Sumika Bayer Urethane Co., Ltd.), Coronate (registered trademark) HL, HX, L (manufactured by Nippon Polyurethane Industry Co., Ltd.), P301-75E (manufactured by Asahi Kasei Corporation), and Barnock (registered trademark) D-750 (manufactured by DIC Corporation) can be exemplified.

[0123] Among them, as the 3 or more functional polyisocyanate of the adduct type, TAKENATE (registered trademark) D-110N, D-120N, D-140N, D-160N manufactured by Mitsui Chemicals, Inc. or Barnock (registered trademark) D-750 manufactured by DIC Corporation is preferable.

[0124] As the 3 or more functional polyisocyanate of the isocyanurate type, for example, TAKENATE (registered trademark) D-127N, D-170N, D-170HN, D-172N, D-177N, D-204, D-204EA-1, D-262, D-268, D-370N, D-376N (all of which are manufactured by Mitsui Chemicals, Inc.), SUMIDUR N3300, Desmodur (registered trademark) N3600, N3900, Z4470BA (manufactured by Sumika Bayer Urethane Co., Ltd.), Coronate (registered trademark) HX, HK (manufactured by Nippon Polyurethane Industry Co., Ltd.), Duramate (registered trademark) TPA-100, TKA-100, TSA-100, TSS-100, TLA-100, TSE-100 (manufactured by Asahi Kasei Corporation) can be exemplified.

[0125] As the polyisocyanate of the biuret type, for example, TAKENATE (registered trademark) D-165N, NP1100 (manufactured by Mitsui Chemicals, Inc.), Desmodur (registered trademark) N3200 (manufactured by Sumika Bayer Urethane Co., Ltd.), Duramate (registered trademark) 24A-100 (manufactured by Asahi Kasei Corporation) can be exemplified.

[0126] Also, as the polyisocyanate, a polymethylene polyphenyl polyisocyanate is also preferable.

[0127] As the polymethylene polyphenyl polyisocyanate, a compound represented by formula (X) is preferable.

[0128] [Chemical Formula 1]

[0129]

[0130] In formula (X), n represents the number of repeating units. As the number of repeating units, an integer of 1 or more is represented, and from the viewpoint that the effects of the present application are more excellent, it is preferable that n be an integer of 1 to 10, and more preferably an integer of 1 to 5.

[0131] As the polyisocyanate containing a polymethylene polyphenyl polyisocyanate, for example, MILLIONATE MR-100, MILLIONATE MR-200, MILLIONATE MR-400 (manufactured by TOSOH CORPORATION), WANNATE PM-200, WANNATE PM-400 (manufactured by Wanhua Chemical Group Co., Ltd.), Cosmonate M-50, Cosmonate M-100, Cosmonate M-200, Cosmonate M-300 (manufactured by Mitsui Chemicals, Inc.), and VORANATE M-595 (manufactured by Dow Chemical Company) can be exemplified.

[0132] The polyol is a compound having 2 or more hydroxyl groups, and for example, a low molecular polyol (for example, an aliphatic polyol, an aromatic polyol), a polyether-based polyol, a polyester-based polyol, a polylactone-based polyol, a castor oil-based polyol, a polyolefin-based polyol, and a hydroxyl group-containing amine-based compound can be exemplified.

[0133] Further, low molecular polyol means a polyol having a molecular weight of 500 or less. For example, 2-functional low molecular polyols such as ethylene glycol, diethylene glycol, and propylene glycol; 3-functional or more low molecular polyols such as glycerol, trimethylolpropane, hexanetriol, pentaerythritol, and sorbitol can be exemplified.

[0134] Further, from the viewpoint of controlling the softness of the microcapsule and further suppressing the reduction of the tensile breaking strength and the viewpoint of improving the heat resistance, as the above polyol, a low molecular polyol is preferred, a 3-functional or more low molecular polyol is more preferred, and a 3-functional low molecular polyol is further preferred.

[0135] Further, as the hydroxyl group-containing amine-based compound, for example, an amino alcohol can be exemplified as an oxyalkylated derivative of an amino compound. As the amino alcohol, for example, an oxirane or oxrane adduct of an amino compound such as ethylenediamine, i.e., N,N,N',N'-tetra[2-hydroxypropyl]ethylenediamine, N,N,N',N'-tetra[2-hydroxyethyl]ethylenediamine, and the like can be exemplified.

[0136] Polyamine is a compound having two or more amino groups (primary or secondary amino groups), and aliphatic polyamines such as diethylenetriamine, triethylenetetramine, 1,3-propanediamine, tetraethylenepentamine, and hexamethylenediamine; an epoxy compound adduct of an aliphatic polyamine; alicyclic polyamines such as piperazine; and heterocyclic diamines such as 3,9-bis-aminopropyl-2,4,8,10-tetraoxaspiro-(5,5)undecane can be exemplified.

[0137] Further, from the viewpoint of improving the heat resistance of the resin, as the above polyamine, a low molecular polyamine is preferred, a 3-functional or more low molecular polyamine is more preferred, and a 3- to 4-functional low molecular polyamine is further preferred.

[0138] Further, low molecular polyamine means a polyamine having a molecular weight of 500 or less.

[0139] Further, from the viewpoint of reducing the exudation of the heat storage material even when a molded product molded using the resin particles is exposed to a high-temperature environment, it is preferred that the resin contained in the capsule wall has a structure represented by Formula (Y).

[0140] In the case where the compound represented by the above Formula (X) is used as a raw material of a polyisocyanate, the structure represented by Formula (Y) corresponds to a structure contained in the obtained resin.

[0141] [Chemical Formula 2]

[0142]

[0143] In formula (Y), n represents the number of repeating units. As the number of repeating units, an integer of 1 or more is represented, and from the viewpoint of more excellent effects of the present application, it is preferable that n be an integer of 1 to 10, and more preferably an integer of 1 to 5.

[0144] wherein, from the viewpoint that even if the molded product molded using the resin particles is exposed to a high-temperature environment, the exudation of the heat storage material is less, it is preferable that the resin contained in the capsule wall be a resin formed by reacting an aromatic or alicyclic diisocyanate, a compound having 3 or more active hydrogen groups in one molecule, and a polymethylene polyphenyl polyisocyanate.

[0145] Further, as the above-mentioned aromatic or aliphatic diisocyanate, from the viewpoint of heat resistance, it is preferable that an aromatic diisocyanate be used. Also, as the compound having 3 or more active hydrogen groups in one molecule, a polyol is preferable, and a low-molecular polyol is more preferable.

[0146] In particular, it is preferable that the resin contained in the capsule wall be formed using an adduct of an aromatic or alicyclic diisocyanate and a compound having 3 or more active hydrogen groups in one molecule, that is, a polyisocyanate A having 3 or more functions (hereinafter, also referred to simply as "polyisocyanate A"), and a polyisocyanate B selected from an aromatic diisocyanate and a polymethylene polyphenyl polyisocyanate (hereinafter, also referred to simply as "polyisocyanate B").

[0147] That is, the capsule wall is preferably a capsule wall containing the above-mentioned resin (at least one resin selected from a polyurea, a polyurethane urea, and a polyurethane) formed using the above-mentioned polyisocyanate A and polyisocyanate B.

[0148] By using the above-mentioned polyisocyanate A and polyisocyanate B, the effects of the present application are more excellent. Also, by using the above-mentioned polyisocyanate A and polyisocyanate B, the destruction of the microcapsules is suppressed under high-temperature conditions.

[0149] Further, as the polyisocyanate A, an adduct of a polyol and a polyisocyanate is used, and in the case where it is reacted with the polyisocyanate B, the same as the reaction product of a polyol and a polyisocyanate, as a result, a polyurethane urea is obtained in most cases.

[0150] Further, as the polyisocyanate B, an aromatic diisocyanate can be used alone, a polymethylene polyphenyl polyisocyanate can be used alone, or both can be used in a mixture. Among them, as the polyisocyanate B, a mixture of an aromatic diisocyanate and a polymethylene polyphenyl polyisocyanate is preferable.

[0151] The mass ratio of the polymethylene polyphenyl polyisocyanate to the aromatic diisocyanate (mass of the polymethylene polyphenyl polyisocyanate / mass of the aromatic diisocyanate) in the above mixture is not particularly limited, and is preferably 0.1 to 10, more preferably 0.5 to 2, and further preferably 0.75 to 1.5.

[0152] The viscosity of the polyisocyanate B is not particularly limited, and is preferably 100 to 1000 mPa-s from the viewpoint of more excellent effects of the present application.

[0153] In addition, the above viscosity is a viscosity at 25°C.

[0154] In the case where the polyisocyanate A and the polyisocyanate B are used in combination, the mass ratio of the polyisocyanate A to the polyisocyanate B (mass of the polyisocyanate A / mass of the polyisocyanate B) is not particularly limited, and is preferably 98 / 2 to 20 / 80, more preferably 90 / 10 to 30 / 70, and further preferably 85 / 15 to 40 / 60.

[0155] In the case where the above mass ratio is within the above range, the effects of the present application are more excellent.

[0156] The mass of the capsule wall in the microcapsule is not particularly limited, and is preferably 5 to 60 mass%, and more preferably 15 to 40 mass% with respect to the total mass of the microcapsule.

[0157] (Properties of the microcapsule)

[0158] The average particle diameter of the microcapsule is not particularly limited, and is preferably 1 to 500 μm, more preferably 1 to 200 μm, further preferably 1 to 100 μm, and particularly preferably 2 to 50 μm. The appearance of a molded product is more excellent in the case where the particle diameter of the microcapsule is small.

[0159] The average inner diameter of the microcapsule is not particularly limited, and is preferably 200 μm or less, more preferably 1 to 100 μm, and further preferably 2 to 50 μm from the viewpoint of more excellent effects of the present application. The inner diameter of the microcapsule indicates the diameter of the core.

[0160] The average particle diameter and the average inner diameter of the microcapsule can be controlled by changing the dispersion conditions in the emulsification step in the method described below with respect to the production method of the microcapsule described later.

[0161] The average particle diameter and the average inner diameter of the microcapsule can be measured by the following method.

[0162] First, a molded product produced using resin particles or a cross-section slice of the resin particles is produced, and the cross-section thereof is observed at 1000 times by a scanning electron microscope (SEM). Figure 1is a partial schematic view of an SEM image of a cross section of the resin particles 13. From the SEM image of the cross section, the interior of the microcapsules 10 (the contents 10b), the capsule wall 10a, and the thermoplastic resin 12 are observed distinctly. From the microcapsules 10 present in the field of view observed, the particle diameters and the inner diameters of 20 microcapsules, in order from the largest microcapsule 10, are measured, and the average is found by performing an arithmetic average of these. This operation is performed in five fields of view, the average of the averages found at each place is found, and the value obtained is taken as the average particle diameter and the average inner diameter of the microcapsules. In addition, when the microcapsules are observed, the inner diameter measured above is the longest inner diameter.

[0163] The thickness of the capsule wall of the microcapsule (wall thickness) is not particularly limited, and is preferably 10.00 μm or less, more preferably 5.00 μm or less, and further preferably 2.00 μm or less, from the viewpoint that the effects of the present application are more excellent. On the other hand, since the strength of the capsule wall can be maintained by having a certain degree of thickness, the wall thickness is preferably 0.01 μm or more, more preferably 0.10 μm or more, and further preferably 0.2 μm or more, from the viewpoint that even if the molded article molded using the resin particles is exposed to a high-temperature environment, the exudation of the heat storage material is less.

[0164] The wall thickness refers to the average found by finding the wall thickness (μm) of each of 20 microcapsules and performing an average.

[0165] Specifically, a cross section slice of the molded article produced using the resin particles or the resin particles is produced, the cross section thereof is observed using an SEM, and with respect to microcapsules of a size of the average particle diameter ± 10% calculated by the above-described measurement method, 20 microcapsules are selected. The cross section of each of these selected microcapsules is observed and the wall thickness is measured, and the average of the 20 microcapsules is calculated, whereby the wall thickness of the microcapsule is found.

[0166] When the average particle diameter of the above-described microcapsule is taken as Dm [unit: μm] and the thickness of the capsule wall of the above-described microcapsule is taken as δ [unit: μm], the ratio of the thickness of the capsule wall of the microcapsule to the average particle diameter of the microcapsule (δ / Dm) is preferably 0.300 or less, more preferably 0.200 or less, and further preferably 0.100 or less.

[0167] From the viewpoint that the strength of the microcapsule can be maintained, the lower limit value of δ / Dm is preferably 0.001 or more, more preferably 0.005 or more, and further preferably 0.010 or more.

[0168] The glass transition temperature of the capsule wall of the microcapsule is not particularly limited, and is preferably 150°C or higher, or the capsule wall does not exhibit a glass transition temperature. That is, the glass transition temperature of the material constituting the capsule wall of the microcapsule is preferably 150°C or higher, or the material constituting the capsule wall of the microcapsule does not exhibit a glass transition temperature.

[0169] In addition, in the case where the capsule wall of the microcapsule exhibits a glass transition temperature, the temperature thereof is preferably 160°C or higher, more preferably 180°C or higher, and further preferably 200°C or higher, from the viewpoint of more excellent heat resistance. In the case where the capsule wall of the microcapsule exhibits a glass transition temperature, the upper limit of the temperature thereof is not particularly limited, and is generally 250°C or lower, in many cases, the thermal decomposition temperature of the capsule wall of the microcapsule.

[0170] Among them, from the viewpoint of more excellent heat resistance, it is preferable that the capsule wall of the microcapsule does not exhibit a glass transition temperature.

[0171] In addition, the fact that the capsule wall of the microcapsule does not exhibit a glass transition temperature means that the capsule wall of the microcapsule (the material constituting the capsule wall of the microcapsule) does not exhibit a glass transition temperature from 25°C to a temperature obtained by subtracting 5°C from the thermal decomposition temperature of the capsule wall described later (thermal decomposition temperature - 5°C). That is, it means that it does not exhibit a glass transition temperature in the range of "25°C" to "(thermal decomposition temperature (°C) - 5°C)".

[0172] The method of making the glass transition temperature of the capsule wall of the microcapsule 150°C or higher or making the capsule wall not exhibit a glass transition temperature is not particularly limited, and is adjusted by appropriately selecting the raw material at the time of manufacturing the microcapsule. For example, since polyurea has a property of exhibiting a high glass transition temperature, a method of constituting the capsule wall with polyurea can be exemplified. Also, a method of increasing the crosslinking density in the material constituting the capsule wall can be exemplified. Furthermore, a method of introducing an aromatic ring group (for example, a benzene ring group) in the material constituting the capsule wall can be exemplified.

[0173] As a method of measuring the glass transition temperature of the capsule wall of the microcapsule, the following method can be exemplified.

[0174] Ethyl acetate was added to the microcapsule, and stirred at 25°C for 24 hours. Then, the obtained solution was filtered, and the obtained residue was vacuum-dried at 60°C for 48 hours, thereby obtaining a microcapsule in which nothing was contained in the inside (hereinafter, also simply referred to as "measurement material"). That is, the capsule wall material of the microcapsule, which is the measurement object of the glass transition temperature, was obtained.

[0175] Next, the thermal decomposition temperature of the obtained measurement material was measured using a thermogravimetric differential thermal analysis device TG-DTA (device name: DTG-60, SHIMADZU CORPORATION). In addition, the thermal decomposition temperature refers to the temperature at which the measurement material is heated from room temperature at a constant rate of temperature increase (10°C / min) in a thermal gravimetric analysis (TGA) in an atmospheric environment, and the amount of the measurement material before heating is reduced by 5% by mass. The temperature at which the amount is reduced by 5% by mass is taken as the thermal decomposition temperature (°C).

[0176] Next, the glass transition temperature of the measurement material was measured using a differential scanning calorimeter DSC (device name: DSC-60a Plus, SHIMADZU CORPORATION) and using a sealed pan at a rate of temperature increase of 5°C / min and in the range of 25°C to (thermal decomposition temperature (°C) - 5°C). As the glass transition temperature of the capsule wall of the microcapsule, the value at the time of heating in the second cycle was used.

[0177] The thermal decomposition temperature of the capsule wall of the microcapsule is not particularly limited, and from the viewpoint of more excellent heat resistance, it is preferably 200°C or higher, more preferably 220°C or higher, and further preferably 230°C or higher.

[0178] The thermal decomposition temperature of the capsule wall refers to the temperature at which the capsule wall is reduced by 5% by mass. The measurement method can be exemplified by the method using a thermogravimetric differential thermal analysis device TG-DTA (device name: DTG-60, SHIMADZU CORPORATION) performed when measuring the glass transition temperature described above.

[0179] The content of the microcapsule in the resin particles is not particularly limited, and the content of the heat storage material is adjusted to the range described above. More specifically, from the viewpoint of more excellent effects of the present application and the viewpoint of more excellent heat storage properties of the resin particles, the content of the microcapsule is preferably 10 to 85% by mass, more preferably 20 to 80% by mass, further preferably 25 to 75% by mass, and particularly preferably 35 to 65% by mass, with respect to the total mass of the resin particles. If the amount of the microcapsule in the resin particles is large, the heat storage amount is excellent, and if the amount of the microcapsule is small, the tensile fracture strength of the molded product obtained using the resin particles is more excellent.

[0180] (Method for producing microcapsule)

[0181] The method for producing the microcapsule is not particularly limited, and a publicly known method can be used.

[0182] For example, an interfacial polymerization method including the following steps can be exemplified: a step of preparing an emulsion by dispersing an oil phase containing a heat storage material and a capsule wall material in an aqueous phase containing an emulsifier (emulsification step); and a step of forming a capsule wall by polymerizing the capsule wall material on the interface between the oil phase and the aqueous phase, thereby forming microcapsules (encapsulation step).

[0183] In addition, the capsule wall material refers to a material that can form a capsule wall.

[0184] Hereinafter, each step of the interfacial polymerization method will be described in detail.

[0185] In the emulsification step of the interfacial polymerization method, an emulsion is prepared by dispersing an oil phase containing a heat storage material and a capsule wall material in an aqueous phase containing an emulsifier. In addition, the capsule wall material contains at least a polyisocyanate and at least one compound selected from a polyol and a polyamine.

[0186] The emulsion is formed by dispersing an oil phase containing a heat storage material and a capsule wall material in an aqueous phase containing an emulsifier.

[0187] The oil phase contains at least a heat storage material and a capsule wall material, and can further contain a solvent and / or an additive, etc., as necessary. From the viewpoint of excellent dispersion stability, as the solvent that can be contained in the oil phase, a non-water-soluble organic solvent is preferable, and ethyl acetate, methyl ethyl ketone, or toluene is more preferable.

[0188] The aqueous phase can contain at least an aqueous medium and an emulsifier.

[0189] As the aqueous medium, water and a mixed solvent of water and a water-soluble organic solvent can be exemplified, and water is preferable. "Water-soluble" means that the solubility of the object substance in 100 mass% of water at 25°C is 5 mass% or more.

[0190] The content of the aqueous medium is not particularly limited, and is preferably 20 to 80 mass%, more preferably 30 to 70 mass%, and further preferably 40 to 60 mass%, relative to the total mass of the emulsion which is a mixture of the oil phase and the aqueous phase.

[0191] As the emulsifier, a dispersant, a surfactant, and a combination thereof can be exemplified.

[0192] As the dispersant, a publicly known dispersant can be used, and polyvinyl alcohol is preferable.

[0193] As the surfactant, a nonionic surfactant, an anionic surfactant, a cationic surfactant, and an amphoteric surfactant can be exemplified. The surfactant can be used alone or in combination of two or more.

[0194] The content of the emulsifier is preferably more than 0 mass% and 20 mass% or less, more preferably 0.005 to 10 mass%, further preferably 0.01 to 10 mass%, particularly preferably 1 to 5 mass%, with respect to the total mass of the mixture of the oil phase and the water phase, i.e., the emulsion.

[0195] The water phase can contain, as needed, other components such as ultraviolet absorbers, antioxidants, and preservatives.

[0196] The dispersion refers to the dispersion of the oil phase as oil droplets in the water phase (emulsification). The dispersion can be performed using a method generally used in the dispersion of the oil phase and the water phase (e.g., a homogenizer, a Manton-Gaulin high-pressure homogenizer, an ultrasonic disperser, a dissolver, a Keddy Mill, and other publicly known dispersion devices).

[0197] The mixing ratio of the oil phase and the water phase (mass of the oil phase / mass of the water phase) is preferably 0.1 to 1.5, more preferably 0.2 to 1.2, further preferably 0.4 to 1.0.

[0198] In the encapsulation step, the capsule wall material is polymerized at the interface between the oil phase and the water phase to form a capsule wall, thereby forming microcapsules.

[0199] The polymerization is preferably performed under heating. The reaction temperature in the polymerization is preferably 40 to 100°C, more preferably 50 to 80°C. Also, the reaction time of the polymerization is preferably about 0.5 to 10 hours, more preferably about 1 to 5 hours.

[0200] In the polymerization, it is preferable to add an aqueous solution (e.g., water, an aqueous acetic acid solution, etc.) to reduce the collision probability of the microcapsules with each other, in order to prevent the microcapsules from coagulating with each other.

[0201] Also, it is preferable to perform sufficient stirring.

[0202] In addition, a coagulation-preventing dispersant can be added to the reaction system in the polymerization.

[0203] In addition, a charge adjusting agent such as nigrosine or other arbitrary auxiliary agent can be added to the reaction system in the polymerization, as needed.

[0204] <Thermoplastic Resin>

[0205] The resin contained in the resin particles is not particularly limited, and publicly known thermoplastic resins can be exemplified.

[0206] As the thermoplastic resin, for example, AS (acrylstyrene) resin, ABS (acrylstyrene butadiene styrene) resin, polyethylene resin, polyester resin (polyether ester elastomer, etc.), polypropylene resin, ethylene-propylene copolymer, polyvinylidene chloride, polyamide, acetal resin, polycarbonate resin, polyphenylene sulfide resin, polyether imide resin, aromatic polyether ketone resin, polysulfone resin, fluorine resin (polyvinylidene fluoride, etc.), polyamide imide resin, and acrylic resin can be exemplified. Among them, polypropylene resin, polyethylene resin, ABS (acrylstyrene butadiene styrene) resin, or polyester resin is preferable.

[0207] The melting point of the thermoplastic resin is not particularly limited, and from the viewpoint of more excellent heat resistance of the molded product, it is preferably 110°C or higher, more preferably 130°C or higher. The upper limit is not particularly limited, and from the viewpoint of more excellent moldability of the molded product, it is preferably 300°C or lower, more preferably 250°C or lower.

[0208] As a method for measuring the melting point of the thermoplastic resin, differential scanning calorimeter DSC or the like can be exemplified.

[0209] As the thermoplastic resin, from the viewpoint of more excellent effects of the present application, a non-water-soluble resin is preferable.

[0210] The "non-water-soluble" in the non-water-soluble resin means that the solubility of the object substance of 100 mass% with respect to water at 25°C is less than 5 mass%.

[0211] The content of the thermoplastic resin in the resin particles is not particularly limited, and the content of the heat storage material can be adjusted to the above range. More specifically, from the viewpoint of more excellent effects of the present application and more excellent heat storability of the resin particles, the content of the thermoplastic resin is preferably 15 to 85 mass%, more preferably 20 to 80 mass%, further preferably 20 to 75 mass%, particularly preferably 35 to 65 mass% with respect to the total mass of the resin particles. The more the content of the thermoplastic resin in the resin particles, the more excellent the tensile fracture strength of the molded product obtained using the resin particles, and the less the content, the more excellent the heat storage amount.

[0212] <Other components>

[0213] The resin particles can contain other components than the microcapsules and the thermoplastic resin described above.

[0214] As the other components, for example, fillers, stabilizers, oxidation-reduction agents, molding aids, decomposition inhibitors, lubricants, release agents, coloring agents such as pigments, dispersants, and plasticizers can be exemplified.

[0215] The filler is not particularly limited, and for example, inorganic fillers such as glass, silica, wollastonite, aluminum hydroxide, kaolin, titanium oxide, alumina, mica, talc, carbon, and potassium titanate, and metal fillers such as copper can be exemplified. The above-mentioned fillers can be in the form of particles, fibers, and whiskers.

[0216] <Resin particles>

[0217] The resin particles contain the above-mentioned microcapsules and a thermoplastic resin.

[0218] The shape of the resin particles is not particularly limited, and the size thereof is also not particularly limited.

[0219] As the shape of the resin particles, a cylindrical shape or a prismatic shape is preferable, and a cylindrical shape is more preferable. For example, a cylindrical particle having a height of 0.01 to 100 mm (preferably 0.05 to 10 mm) and a diameter of 0.01 to 50 mm (preferably 0.05 to 30 mm) is more preferable.

[0220] The heat storage amount of the resin particles is preferably high, and is preferably 40 J / g or more, more preferably 50 J / g or more, and further preferably 70 J / g or more. The upper limit is not particularly limited, and is mostly 300 J / g or less.

[0221] The heat storage amount can be measured by a differential scanning calorimeter (DSC).

[0222] The tensile breaking strength of the resin particles is preferably a value close to the original tensile breaking strength of the thermoplastic resin, and the difference between the tensile breaking strength of the resin particles and the tensile breaking strength of the thermoplastic resin contained in the resin particles is preferably 0 to 20 MPa or less, more preferably less than 0 to 10 MPa, and further preferably less than 0 to 5 MPa.

[0223] <Method for producing resin particles>

[0224] The method for producing the resin particles is not particularly limited, and publicly known methods can be exemplified.

[0225] For example, a method in which the microcapsules and the resin are melt-kneaded in an extruder, and the extruded thread is cut to become particles can be exemplified.

[0226] It is preferable that the microcapsules use powder microcapsules. As a method for obtaining powder of the microcapsules, for example, a method in which a solvent is removed from a dispersion liquid of the microcapsules obtained by the above-mentioned interfacial polymerization method to obtain powder of the microcapsules can be exemplified. As a method for removing the above-mentioned solvent, for example, a method in which a spray drier is used to obtain powder of the microcapsules from the dispersion liquid of the microcapsules can be exemplified.

[0227] Among them, from the viewpoint of further suppressing the breakage of the microcapsules during melt kneading, a method in which the thermoplastic resin is melt-kneaded in an extruder, the microcapsules are added to the melt of the thermoplastic resin in the extruder, and further melt-kneading is performed, and the strand extruded from the extruder is cut to produce the resin particles is preferred.

[0228] The above method can be implemented by using an extruder provided with a plurality of raw material supply ports. For example, melt-kneading can be performed by supplying a thermoplastic resin to an extruder provided with a plurality of raw material supply ports, supplying microcapsules to the extruder from a raw material supply port located on the downstream side of the raw material supply port from which the thermoplastic resin is supplied, and further melt-kneading, and the strand extruded from the extruder is cut to produce the resin particles.

[0229] The above method corresponds to a method in which the microcapsules are fed to an extrusion molding machine and mixed with a thermoplastic resin in a softened state. Side feeding refers to a method in which a feeder that supplies the microcapsules and a feeder that supplies the thermoplastic resin are provided separately, and is fed to the thermoplastic resin that is preliminarily kneaded in the extruder.

[0230] As the extruder, a publicly known device can be used, and for example, a publicly known extrusion molding machine (for example, a twin-screw extruder) can be cited.

[0231] <Shaped article>

[0232] A shaped article is obtained by molding using the resin particles of the present application.

[0233] In the shaped article that is molded, the microcapsules and the thermoplastic resin are contained.

[0234] The molding method using the resin particles is not particularly limited, and a publicly known molding method can be used. For example, extrusion molding, injection molding, blow molding, compression molding, press molding, molding by a 3D printer, and the like can be cited.

[0235] As the shaped article molded using the resin particles of the present application, for example, automobile parts, electronic device parts, and fibers (clothing) can be cited.

[0236] As the automobile parts, for example, engine casings, battery casings, heat exchangers, interior parts, and intake system piping of vehicles can be cited.

[0237] As the electronic device parts, for example, frame bodies and battery casings can be cited.

[0238] Example

[0239] The following describes examples and comparative examples and further concretely explains the features of the present application. The materials, amounts, proportions, processing contents, processing sequences, and the like shown in the following examples can be appropriately changed without departing from the gist of the present application. Therefore, the scope of the present application is not to be construed as being limited by the specific examples shown below.

[0240] <Example 1>

[0241] As the heat accumulating material, 100 parts by mass of eicosane (manufactured by Sasol Limited.) was dissolved in 120 parts by mass of ethyl acetate to obtain a solution A. Further, 25 parts by mass of a trimethylolpropane adduct of toluene diisocyanate (BURNOCK D-750, containing 25% of ethyl acetate, manufactured by DIC Corporation) was added to the solution A being stirred to obtain a solution B. Further, 170 parts by mass of a 3% by mass aqueous solution of polyvinyl alcohol (KURARAY POVAL KL-318, manufactured by KURARAY CO., LTD.) was added to the solution B to perform emulsion dispersion. To the emulsion after the emulsion dispersion, 300 parts by mass of water was added, and while stirring, the temperature was raised to 70°C, and after stirring for 1 hour, the temperature was lowered. Further, water was added to the obtained solution to adjust the concentration, and a microcapsule liquid containing the heat accumulating material having a solid content concentration of 20% was obtained.

[0242] The capsule wall of the microcapsule contains polyurethane urea.

[0243] The average particle diameter of the obtained microcapsule was 5 μm.

[0244] As shown in the following structural formula, the above BURNOCK D-750 corresponds to an adduct of aromatic diisocyanate and trimethylolpropane, i.e., a 3-functional polyisocyanate.

[0245] [Chemical Formula 3]

[0246]

[0247] Next, the microcapsule liquid containing the heat accumulating material prepared above was powderized using a spray dryer (Mini Spray Dryer B-290, manufactured by BUCHI Corporation) to obtain a powder of the microcapsule containing the heat accumulating material.

[0248] Using a twin-screw extruder (2D25S) having a first raw material feeding port disposed on the upstream side and a second raw material feeding port disposed on the downstream side, under the condition that the melting temperature was 200°C, as a thermoplastic resin, 100 parts by mass of a polypropylene resin (Novatec PP MA-3, manufactured by Japan Polypropylene Corporation) was fed to the twin-screw extruder from the first raw material feeding port, and the polypropylene resin was melted. At this time, 100 parts by mass of the powder of the microcapsule containing the heat accumulating material described above was fed to the twin-screw extruder from the second raw material feeding port, and the powder of the microcapsule containing the heat accumulating material was fed to the melt of the thermoplastic resin. The melt obtained in the twin-screw extruder was extruded from a die to become a strand, and by cutting the strand, it became a pellet to produce a cylindrical resin pellet (3 mm in diameter and 3 mm in height).

[0249] Using the resin pellet described above, a plate of a molded product having a length of 150 mm, a width of 50 mm, and a thickness of 1 mm was produced by injection molding.

[0250] <Examples 2 to 25>

[0251] As shown in Table 1 described later, except for changing the types and amounts of use of the polyisocyanate A, the polyisocyanate B, the heat accumulating material, and the resin, and the respective properties (particle diameter, wall thickness, δ / D, glass transition temperature, thermal decomposition temperature) of the microcapsule, the resin pellet and the plate were produced in the same order as in Example 1.

[0252] In addition, in Examples 2 to 25, the polyisocyanate A and the polyisocyanate B were used in a predetermined mass ratio instead of BURNOCK D-750 used in Example 1. The total mass of the polyisocyanate A and the polyisocyanate B was the same as the amount of use of BURNOCK D-750 used in Example 1.

[0253] <Comparative Example 1>

[0254] The resin pellet was produced in the order of Example 1 of Patent Document 1. Using the produced resin pellet, the plate was produced in the same order as in Example 1.

[0255] In addition, the capsule wall of the microcapsule used in Comparative Example 1 was composed of a melamine resin.

[0256] <Comparative Example 2>

[0257] The resin pellet was produced in the order of Example 6 of Japanese Patent Application Publication No. 2019-218518. Using the produced resin pellet, the plate was produced in the same order as in Example 1.

[0258] In addition, in Comparative Example 2, a porous body (silica) was used as the heat storage material particles.

[0259] [Comparative Example 3]

[0260] Resin particles were produced in the order of Example 10 of Patent Document 2, except that the heat storage material used was changed to paraffin (eicosane). Using the resin particles produced, a sheet was produced in the same order as Example 1.

[0261] In addition, in Comparative Example 3, the content of the heat storage material was 74 mass% relative to the total mass of the resin particles.

[0262] In Table 1, "D-120N" indicates TAKENATE D-120N. TAKENATE D-120N corresponds to an adduct of an alicyclic diisocyanate and trimethylolpropane, i.e., a 3-functional polyisocyanate, as shown in the following structural formula.

[0263] [Chemical Formula 4]

[0264]

[0265] In Table 1, "MR-100" indicates MILLIONATE MR-100, "MR-200" indicates MILLIONATE MR-200, and "MR-400" indicates MILLIONATE MR-400. MILLIONATE MR-100, MILLIONATE MR-200, and MILLIONATE M-400 all correspond to a mixture of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate (corresponding to the compound represented by Formula (X)).

[0266] In Table 1, the column of "mass ratio (A / B)" indicates the ratio of the mass of polyisocyanate A relative to the mass of polyisocyanate B.

[0267] In Table 1, the column of "amount (relative to the capsule) [mass%]" in the column of "heat storage material" indicates the content (mass%) of the heat storage material relative to the total mass of the microcapsules.

[0268] In Table 1, the column of "particle diameter (μm)" indicates the average particle diameter (μm) of the microcapsules.

[0269] In Table 1, the column of "wall thickness" indicates the wall thickness of the capsule wall of the microcapsules.

[0270] In Table 1, the column of "inner diameter (μm)" indicates the average inner diameter (μm) of the microcapsules.

[0271] In Table 1, the column of "δ / D" indicates the ratio of the number average wall thickness (μm) of the microcapsules, i.e., δ, relative to the average particle diameter (μm) of the microcapsules, i.e., D.

[0272] In Table 1, the column of "thermal decomposition temperature [°C]" indicates the thermal decomposition temperature (°C) of the capsule wall of the microcapsule.

[0273] In Table 1, the column of "kind" of the column of "resin" indicates the kind of the thermoplastic resin.

[0274] In Table 1, the column of "amount [mass %]" of the column of "resin" indicates the content (mass %) of the thermoplastic resin with respect to the total mass of the resin particles.

[0275] In Table 1, the column of "amount of heat storage material (with respect to the resin particles) [mass %]" indicates the content (mass %) of the heat storage material with respect to the total mass of the resin particles.

[0276] In Table 1, "PP" of the column of "resin" indicates Novatec PP MA-3 (manufactured by Japan Polypropylene Corporation, melting point 170°C, polypropylene resin), "PE" indicates Novatec HD HJ360 (melting point 132°C, polyethylene resin), "ABS" indicates Toyorak 600-309 (manufactured by TORAY INDUSTRIES, INC., melting point 130 to 150°C, ABS resin), "elastomer" indicates Hytrel 3046 (manufactured by Du Pont Company, melting point 160°C, polyether ester resin), and "PVA" indicates polyvinyl alcohol.

[0277] In addition, the polypropylene, the polyethylene, the ABS resin, and the polyether ester resin correspond to the non-water-soluble resin.

[0278] <Evaluation>

[0279] (Heat storage amount)

[0280] The heat storage amount of the resin particles produced in the examples and the comparative examples was measured based on a differential scanning calorimeter (DSC7020, manufactured by Hitachi High-Tech Science Corporation).

[0281] (Heat resistance (bleeding))

[0282] After the plate produced in the examples and the comparative examples was subjected to a treatment at 80°C for 4 hours, whether or not bleeding (leakage) was observed was confirmed by visual observation, and the evaluation was performed in accordance with the following criteria.

[0283] A: No bleeding was confirmed.

[0284] B: Slight bleeding was confirmed.

[0285] C: Obvious bleeding was confirmed.

[0286] (tensile strength at break)

[0287] The tensile strength at break was measured according to JIS K7161 for each of the sheets produced in the examples and comparative examples.

[0288] Also, using each of the resins used in each of the examples and comparative examples, a molded product, i.e., a comparative sheet, having a length of 150 mm, a width of 50 mm, and a thickness of 1 mm was produced by injection molding. Using the comparative sheet, the tensile strength at break was measured according to JIS K7161 for each of the comparative sheets.

[0289] The tensile strength at break of the sheet produced in each of the examples and comparative examples and the tensile strength at break of the comparative sheet corresponding to each of the examples and comparative examples were compared to find the difference between the two, and evaluated according to the following criteria.

[0290] A: less than 5 MPa

[0291] B: 5 MPa or more and less than 10 MPa

[0292] C: 10 MPa or more

[0293] [Table 1]

[0294]

[0295] As shown in Table 1, it was confirmed that the resin particles of the present application exhibited the desired effects.

[0296] From the comparison between Example 1 and the other examples, it was confirmed that the effects were more excellent in the case where the resin had a polymethylene polyphenyl polyisocyanate structure.

[0297] From the comparison between Examples 2 to 6, it was confirmed that the effects were more excellent in the case where the mass A / B was 90 / 10 to 30 / 70 (preferably 85 / 15 to 40 / 60).

[0298] From the comparison between Example 4 and Example 7, it was confirmed that the effects were more excellent in the case of an aromatic diisocyanate.

[0299] From the comparison between Examples 16 to 19, it was confirmed that the effects were more excellent in the case where the thickness of the capsule wall of the microcapsule was 0.10 to 5.0 μm.

[0300] From the results of Example 15, it was confirmed that the effects were more excellent in the case where δ / D was 0.100 or less.

[0301] From the results of Example 23, the tensile elastic strength was more excellent in the case where the content of the thermoplastic resin was 35% by mass or more relative to the total mass of the resin particles.

[0302] From the results of Example 25, it was confirmed that the heat storage material is excellent in heat storage property when the content of the heat storage material is 20% by mass or more relative to the total mass of the resin particles.

[0303] Explanation of symbols

[0304] 10 - microcapsule, 10a - capsule wall, 10b - content, 12 - thermoplastic resin, 13 - resin particle.

Claims

1. A resin particle which is a resin particle comprising a microcapsule containing a heat accumulating material and a thermoplastic resin, the content of the heat accumulating material is 70 mass% or less relative to the total mass of the resin particle, the capsule wall of the microcapsule contains at least one resin selected from the group consisting of polyurethane urea, polyurethane and polyurea, the resin contained in the capsule wall of the microcapsule is formed using an adduct of an aromatic or alicyclic diisocyanate and a compound having 3 or more active hydrogen groups in one molecule, i.e., a polyisocyanate A having 3 or more functions, and a polyisocyanate B, the polyisocyanate B is a polymethylene polyphenyl polyisocyanate, or a mixture of an aromatic diisocyanate and a polymethylene polyphenyl polyisocyanate.

2. The resin particle according to claim 1, wherein the capsule wall of the microcapsule contains polyurethane urea.

3. The resin particle according to claim 1 or 2, wherein the total content of the microcapsule and the thermoplastic resin is more than 90 mass% relative to the total mass of the resin particle.

4. The resin particle according to claim 1 or 2, wherein the resin contained in the capsule wall of the microcapsule has a structure represented by formula (Y), n represents an integer of 1 or more.

5. The resin particle according to claim 1 or 2, wherein the compound having 3 or more active hydrogen groups in one molecule is a polyol having a molecular weight of 500 or less.

6. The resin particle according to claim 1 or 2, wherein the thermal decomposition temperature of the capsule wall of the microcapsule is 200°C or more.

7. The resin particle according to claim 1 or 2, wherein the thickness of the capsule wall of the microcapsule is 0.10 μm to 5.0 μm.

8. The resin particle according to claim 1 or 2, wherein the average inner diameter of the microcapsule is 200 μm or less.

9. The resin particle according to claim 1 or 2, wherein the melting point of the thermoplastic resin is 110°C or more.

10. The resin particle according to claim 1 or 2, wherein the thermoplastic resin is a non-water-soluble resin.

11. A method for producing the resin particle according to any one of claims 1 to 10, wherein the thermoplastic resin is melt-kneaded in an extruder, the microcapsule is added to the melt of the thermoplastic resin in the extruder and further melt-kneaded, the strand extruded through the extruder is cut, and thereby the resin particle is produced.

12. A molded article which is molded using the resin particle according to any one of claims 1 to 10.

13. An automobile part which is molded using the resin particle according to any one of claims 1 to 10.

14. An electronic device part which is molded using the resin particle according to any one of claims 1 to 10.

15. A fiber which is molded using the resin particle according to any one of claims 1 to 10. ​

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