Resin composition, molded article, and use thereof

Abstract

Provided is a resin composition that contains, as a phase transition material, a heat storage compound having process heat resistance that can be handled even when the resin composition is melt-kneaded with a resin at a relatively high temperature and having a property of not leaking from the resin when formed into a molded body, can control a warm feeling, and can provide a molded body excellent in moldability, brittleness resistance, and lightweight properties.SOLUTION: A resin composition comprising a thermoplastic resin (A), a heat storage compound (B) having a flash point of 155 °C or higher, and a porous inorganic compound (C) having an oil absorption of 4.0g / g or more, wherein the resin (A) comprises 0 to 80 parts by mass of a resin (A1) having a density, MFR, and durometer D hardness within specific ranges and 100 to 20 parts by mass of a resin (A2) having a density, durometer A hardness, tensile elongation at break, and melting temperature within specific ranges, and the content of the (B) is less than 700 parts by mass when the content of the (C) is 100 parts by mass.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a molded article thereof and uses thereof, and more particularly to a thermoplastic resin composition capable of controlling temperature sensation, a molded article thereof and uses thereof. [Background technology]

[0002] A conventional concept is to add a phase-change material with a large heat capacity to resin, making it difficult for the material to change temperature even in the high temperatures of midsummer or the low temperatures of midwinter, and making it difficult to feel hot or cold when touched. This is due to the mechanism by which energy is consumed in the phase transition (solid → liquid, liquid → solid), and by maintaining the phase transition temperature for a certain period of time, it is possible to slow down the rise or fall of temperature. Examples based on this concept include sheets that give a cooling sensation and materials that suppress the temperature rise in steering wheels and instrument panels, which become hot inside cars in the summer.

[0003] Patent Document 1 discloses a resin composition containing the above-mentioned phase transition material, which is a heat storage resin composition containing a thermoplastic resin having a heat of crystalline fusion (ΔHm) of 100 J / g or less and heat storage microcapsules, and having a heat of crystalline fusion (ΔHm) of 50 J / g or more.

[0004] Furthermore, Patent Document 2 discloses a resin pellet containing heat storage material particles, which comprises a thermoplastic resin and heat storage material particles dispersed in the thermoplastic resin and containing a heat storage substance, and in which the particle diameter and other factors of the heat storage material particles satisfy specific conditions. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-116570 [Patent Document 2] Japanese Patent Application Publication No. 2019-218518 Summary of the Invention [Problem to be solved by the invention]

[0006] Resin compositions containing phase change materials such as heat storage compounds are required to have high heat resistance depending on the application. However, the inventions of Patent Documents 1 and 2 both suffer from the problem of insufficient heat resistance due to the low melting point of the thermoplastic resin. Furthermore, when using a highly heat-resistant thermoplastic resin, it may be necessary to melt-knead the phase change material and the thermoplastic resin at relatively high temperatures (e.g., temperatures above 150°C). Therefore, the phase change material is required to have heat resistance that can withstand the process temperatures used when melt-kneading with the resin. Furthermore, excellent moldability is also required, enabling the production of molded articles in various shapes depending on the application. Furthermore, the resulting molded articles are required to have properties such as brittle resistance and light weight, as well as the ability for the phase change material to not leak (bleed out) from the resin. However, such considerations have not been fully addressed in the prior art.

[0007] The present invention aims to provide a resin composition that contains a heat storage compound as a phase change material that has process heat resistance that can withstand even when melt-kneaded with a resin at relatively high temperatures, and that has the property of not leaking (bleeding out) from the resin when formed into a molded article, and that can control the temperature sensation and can give a molded article that is excellent in processability, moldability, brittleness resistance, and light weight, as well as a molded article made from the resin composition, and uses thereof. [Means for solving the problem]

[0008] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, they have found that the above-mentioned problems can be solved by a resin composition containing a specific thermoplastic resin, a heat storage compound, and a porous inorganic compound in specific amounts, and have completed the present invention. Examples of embodiments of the present invention are shown below.

[0009] [1] 100 parts by mass of thermoplastic resin (A), 10 to 100 parts by mass of a heat storage compound (B) (different from the component (A)) having a flash point of 155°C or higher; 1.5 to 20 parts by mass of a porous inorganic compound (C) having an oil absorption of 4.0 g / g or more; Including, The thermoplastic resin (A) is 0 to 80 parts by mass of a thermoplastic resin (A1) satisfying the following requirements (a-1) to (a-3); and 100 to 20 parts by mass of a thermoplastic resin (A2) that satisfies the following requirements (a-1) and (a-4) to (a-6) (the total amount of the thermoplastic resins (A1) and (A2) being 100 parts by mass), A resin composition, wherein the content of the heat storage compound (B) is less than 700 parts by mass when the content of the porous inorganic compound (C) is taken as 100 parts by mass: (a-1) A density measured in accordance with the method described in ASTM D 1505 of 0.80 to 1.0 g / cm 3 is in the range of; (a-2) The melt flow rate (MFR) measured in accordance with the method described in ISO 1133 at 190°C under a load of 2.16 kg is in the range of 10 to 40 g / 10 min; (a-3) The Durometer D hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90; (a-4) The Durometer A hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90; (a-5) The tensile elongation at break measured in accordance with the method described in JIS K6251 is in the range of 800 to 1200%; (a-6) The melting point (Tm) measured by a differential scanning calorimeter (DSC) is 100°C or higher.

[0010] [2] The resin composition according to item [1], wherein the content of the heat storage compound (B) is 60 to 95 parts by mass. [3] The resin composition according to item [1] or [2], wherein the heat storage compound (B) contains a fatty acid ester. [4] The resin composition according to any one of items [1] to [3], wherein the heat storage compound (B) has a crystalline heat of fusion ΔHm of 150 J / g or more.

[0011] [5] The resin composition according to any one of items [1] to [4], wherein the porous inorganic compound (C) comprises at least one compound selected from the group consisting of silica, alumina, and carbon. [6] The resin composition according to any one of items [1] to [5], wherein the porous inorganic compound (C) has an oil absorption of 4.5 g / g or more and 10.0 g / g or less.

[0012] [7] The resin composition according to any one of items [1] to [6], wherein the porous inorganic compound (C) is hydrophobic silica. [8] The resin composition according to any one of items [1] to [7], wherein the content of the porous inorganic compound (C) is 1.5 parts by mass or more and less than 14 parts by mass.

[0013] [9] A molded article made of the resin composition according to any one of items [1] to [8].

[10] A building material comprising the resin composition according to any one of items [1] to [8].

[11] A pillow filling material comprising the resin composition according to any one of items [1] to [8].

[0014]

[12] A method for producing the resin composition according to any one of items [1] to [8], comprising a step of kneading the thermoplastic resin (A), the heat storage compound (B), and the porous inorganic compound (C) at a temperature of 150°C or higher. [Effects of the Invention]

[0015] The resin composition of the present invention can be produced by melt-kneading at a relatively high temperature. Furthermore, by using the resin composition of the present invention, a molded article can be produced that has the property of preventing leakage (bleed-out) of the heat storage compound (phase transition material) from the resin, allows temperature control, and is excellent in processability, moldability, brittle resistance, and light weight. [Brief explanation of the drawings]

[0016] [Figure 1]FIG. 1 is a diagram showing the results of an evaluation of the effect of suppressing the rate of temperature rise / fall performed in an example. DETAILED DESCRIPTION OF THE INVENTION

[0017] The present invention will be described in detail below. [Resin composition] The resin composition according to the present invention comprises: 100 parts by mass of a thermoplastic resin (A) described below, 10 to 100 parts by mass of a heat storage compound (B) (different from the component (A)) having a flash point of 155°C or higher; 1.5 to 20 parts by mass of a porous inorganic compound (C) having an oil absorption of 4.0 g / g or more; Including, The content of the heat storage compound (B) is less than 700 parts by mass when the content of the porous inorganic compound (C) is taken as 100 parts by mass.

[0018] <Thermoplastic resin (A)> The thermoplastic resin (A) used in the present invention contains 0 to 80 parts by mass of a thermoplastic resin (A1) that satisfies the following requirements (a-1) to (a-3), and 100 to 20 parts by mass of a thermoplastic resin (A2) that satisfies the following requirements (a-1) and (a-4) to (a-6) (the total amount of the thermoplastic resins (A1) and (A2) being 100 parts by mass). (a-1) The density measured in accordance with the method described in ASTM D 1505 is 0.80 to 1.0 g / cm 3 The range is. (a-2) The melt flow rate (MFR) measured in accordance with the method described in ISO 1133 at 190°C under a load of 2.16 kg is in the range of 10 to 40 g / 10 min. (a-3) The Durometer D hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90. (a-4) The Durometer A hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90. (a-5) The tensile elongation at break measured in accordance with the method described in JIS K6251 is in the range of 800 to 1200%. (a-6) The melting point (Tm) measured by a differential scanning calorimeter (DSC) is 100°C or higher.

[0019] The density in requirement (a-1) is preferably 0.81 to 0.97 g / cm 3 , more preferably 0.82 to 0.96 g / cm 3 When the densities of the thermoplastic resins (A1) and (A2) are within the above ranges, a molded article with excellent lightness can be obtained.

[0020] The MFR in requirement (a-2) is preferably 11 to 39 g / 10 min, more preferably 12 to 38 g / 10 min. When the MFR of the thermoplastic resin (A1) is within the above range, the resulting resin composition has excellent moldability.

[0021] The Durometer D hardness (instantaneous value) in requirement (a-3) is preferably 40 to 85, more preferably 48 to 82, and even more preferably 55 to 80. When the Durometer D hardness (instantaneous value) of the thermoplastic resin (A1) is within the above range, when the resin composition is heated and kneaded in a twin-screw extruder, strand-cut, and pelletized, the strands are cooled quickly, making it less likely that poor cutting will occur.

[0022] The Durometer A hardness (instantaneous value) in requirement (a-4) is preferably 35 to 85, more preferably 38 to 82, and even more preferably 40 to 80. When the Durometer A hardness (instantaneous value) of the thermoplastic resin (A2) is within the above range, embrittlement is unlikely to occur even when the porous inorganic compound (C) is added within the specified range.

[0023] The tensile elongation at break in requirement (a-5) is preferably 800 to 1200%, more preferably 850 to 1150%, and even more preferably 900 to 1100%. When the tensile elongation at break of the thermoplastic resin (A2) is within the above range, embrittlement is unlikely to occur even when the porous inorganic compound (C) is added within the specified range.

[0024] The melting point (Tm) in requirement (a-6) is preferably 100 to 200° C., more preferably 110 to 190° C., and even more preferably 130 to 180° C. When the melting point (Tm) of the thermoplastic resin (A2) is within the above range, bleeding out of the heat storage compound (B) can be suppressed and processability is excellent.

[0025] The thermoplastic resin (A1) is not particularly limited as long as it satisfies the above requirements (a-1) to (a-3), and the thermoplastic resin (A2) is not particularly limited as long as it satisfies the above conditions (a-1) and (a-4) to (a-6). Examples include olefin-based resins, styrene-based resins, acrylic-based resins, polyester-based resins, polyvinyl chloride-based resins, polyamide-based resins, polycarbonate-based resins, polylactic acid-based resins, polyimide-based resins, polysulfone-based resins, and aromatic polyketone-based resins. These resins can be used alone or in combination of two or more, and commercially available products may also be used. Of the above, olefin-based resins are preferred, and olefin-based thermoplastic elastomers are more preferred.

[0026] A preferred example of the olefin-based thermoplastic elastomer is a dynamically crosslinked product of ethylene-α-olefin-non-conjugated polyene copolymer [I] having 3 to 20 carbon atoms (hereinafter also referred to as "ethylene-α-olefin-non-conjugated polyene copolymer [I]") and polyolefin resin [II].

[0027] The dynamically crosslinked product may be obtained by dynamically crosslinking one kind of ethylene-α-olefin-non-conjugated polyene copolymer [I] or one kind of polyolefin resin [II], or may be obtained by dynamically crosslinking a plurality of kinds of ethylene-α-olefin-non-conjugated polyene copolymers [I] or a plurality of kinds of polyolefin resins [II].

[0028] In this specification, dynamic crosslinking means that the ethylene-α-olefin-non-conjugated polyene copolymer [I] and the polyolefin resin [II] are kneaded in a molten state to crosslink at least a part of the carbon-carbon double bonds in the ethylene-α-olefin-non-conjugated polyene copolymer [I].

[0029] Ethylene-α-olefin-non-conjugated polyene copolymer[I] The ethylene-α-olefin-non-conjugated polyene copolymer [I] contains a structural unit (a) derived from ethylene, a structural unit (b) derived from an α-olefin having 3 to 20 carbon atoms, and a structural unit (c) derived from a non-conjugated polyene.

[0030] The molar ratio (a) / (b) of the constituent unit (a) to the constituent unit (b) in the ethylene-α-olefin-non-conjugated polyene copolymer [I] is preferably 50 / 50 to 95 / 5, more preferably 60 / 40 to 80 / 20, and even more preferably 65 / 35 to 75 / 25.

[0031] On the other hand, the specific amount of the structural unit (c) derived from the non-conjugated polyene in the ethylene-α-olefin-non-conjugated polyene copolymer [I] is preferably 2 to 20 mass % based on the total amount of the ethylene-α-olefin-non-conjugated polyene copolymer [I].

[0032] Specific examples of the α-olefin having 3 to 20 carbon atoms constituting the ethylene-α-olefin-non-conjugated polyene copolymer [I] include propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, and the like.

[0033] Among them, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene are included. The ethylene-α-olefin-non-conjugated polyene copolymer [I] may contain only one type of α-olefin-derived structural unit (b), or may contain two or more types.

[0034] The non-conjugated polyene constituting the ethylene-α-olefin-non-conjugated polyene copolymer [I] may be any compound having no conjugated structure and two or more carbon-carbon double bonds. Specific examples thereof include linear non-conjugated dienes such as 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4,5-dimethyl-1,4-hexadiene, 7-methyl-1,6-octadiene, 8-methyl-4-ethylidene-1,7-nonadiene, and 4-ethylidene-1,7-undecadiene; methyltetrahydroindene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, and 5-bis(2-methyl-2-propanediene). Cyclic non-conjugated dienes such as 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, and 4-ethylidene-8-methyl-1,7-nanodiene are also included.

[0035] Among these non-conjugated polyenes, 5-ethylidene-2-norbornene (ENB) and 5-vinyl-2-norbornene (VNB) are particularly preferred. The ethylene-α-olefin-non-conjugated polyene copolymer [I] may contain only one type of non-conjugated polyene-derived structural unit (c), or may contain two or more types.

[0036] The ethylene-α-olefin-non-conjugated polyene copolymer [I] may be so-called oil-extended rubber, which is prepared by blending a softener, preferably a mineral oil-based softener, during its production. The mineral oil-based softener may be any conventionally known mineral oil-based softener, and examples thereof include paraffin-based process oil.

[0037] The ethylene-α-olefin-non-conjugated polyene copolymer [I] can be produced by a conventionally known method.

[0038] Polyolefin resin [II] The polyolefin resin [II] may be any polyolefin-based resin substantially free of unsaturated bonds in the main chain. Specific examples include homopolymers of α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene; and copolymers thereof. When the polyolefin resin [II] is a copolymer, it is preferable that the content of any one of the α-olefins is 90 mol% or more.

[0039] In particular, the polyolefin resin [II] is preferably a propylene-based polymer (II-1) containing propylene as the main component, or an ethylene-based polymer (II-2) containing ethylene as the main component.

[0040] Examples of the propylene polymer (II-1) include a propylene homopolymer, a random copolymer of propylene and an α-olefin having 2 to 10 carbon atoms (e.g., ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, etc.), a block copolymer of a propylene homopolymer and an amorphous or low-crystalline propylene-ethylene random copolymer, etc. However, the amount of structural units other than propylene is preferably 10 mol % or less of the total amount of structural units.

[0041] The propylene polymer (II-1) may be one polymerized by a known polymerization method, or may be one that is manufactured and sold as a polypropylene resin.

[0042] Furthermore, the propylene polymer (II-1) preferably has an isotactic stereostructure, but may have a syndiotactic structure, a mixture of these structures, or may partially contain an atactic structure.

[0043] On the other hand, examples of the ethylene polymer (II-2) include ethylene homopolymers and random copolymers of ethylene and an α-olefin having 3 to 10 carbon atoms (e.g., propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, etc.). In the ethylene polymer (II-2), the amount of structural units other than ethylene is preferably 10 mol % or less of the total amount of structural units.

[0044] The ethylene polymer (II-2) may be one polymerized by a known polymerization method, or may be one manufactured and sold as high-pressure low-density polyethylene, linear low-density polyethylene, high-density polyethylene, or the like.

[0045] -Method for preparing dynamically crosslinked polymer The dynamically crosslinked product can be prepared by kneading (dynamic crosslinking) the above-mentioned ethylene-α-olefin-non-conjugated polyene copolymer [I] and polyolefin resin [II], and, if necessary, adding a known crosslinking agent, crosslinking aid, and softener. Commercially available products may also be used. For dynamic crosslinking, either a closed-type or an open-type device may be used, but a closed-type device is preferred.

[0046] Dynamic crosslinking is preferably carried out under an atmosphere of an inert gas such as nitrogen or carbon dioxide. The temperature during dynamic crosslinking is usually in the range of from the melting point of the polyolefin resin [II] to 300°C, preferably 150 to 270°C, more preferably 170 to 250°C. The kneading time is preferably 1 to 20 minutes, more preferably 1 to 10 minutes. The shear rate at this time is preferably 10 to 50,000 sec -1 , more preferably 100 to 20,000 seconds -1 is.

[0047] Examples of kneading devices used for dynamic crosslinking include mixing rolls, intensive mixers (for example, Banbury mixers, kneaders), single-screw or twin-screw extruders, etc., with non-open devices being preferred, and twin-screw extruders being particularly preferred.

[0048] <Heat storage compound (B)> The heat storage compound (B) used in the present invention is used as a phase transition material and is a compound having a flash point of 155°C or higher, preferably 156°C or higher and 300°C or lower, more preferably 157°C or higher and 290°C or lower, and even more preferably 158°C or higher and 280°C or lower (provided that it is a compound other than the component (A)). By having a flash point within the above range, it can be incorporated into a resin composition without thermal decomposition even when melt-kneaded with the component (A) and the like at high temperatures of 150°C or higher, and an excellent phase transition effect can be exhibited.

[0049] The heat of crystalline fusion ΔHm of the heat storage compound (B) is preferably 150 J / g or more, more preferably 160 J / g or more and 300 J / g or less, even more preferably 170 J / g or more and 290 J / g or less, and particularly preferably 180 J / g or more and 280 J / g or less. When the heat of crystalline fusion ΔHm of the heat storage compound (B) is within the above range, the above-mentioned effects are enhanced.

[0050] Examples of the heat storage compound (B) include compounds having a non-bulky chain structure that does not contain cyclic or multiple bonds, a structure containing hydrocarbons, and a structure containing hydrogen bonding units such as carbonyl groups and hydroxyl groups. More specifically, examples include fatty acid esters, aliphatic alcohols, and fatty acids. Of these, fatty acid esters are preferred, and fatty acid esters in which the substituents on both ends of the ester are chain-like are more preferred.

[0051] Examples of fatty acid esters include isocetyl myristate, octyldodecyl myristate, isocetyl isostearate, cetyl 2-ethylhexanoate, methyl stearate, isocetyl stearate, 2-ethylhexyl palmitate, isotridecyl stearate, butyl stearate, dodecyl stearate, myristyl myristate, cetyl myristate, methyl palmitate, hexadecyl palmitate, stearyl stearate, and docosyl docosanoate. Among these, methyl stearate, stearyl stearate, myristyl myristate, cetyl myristate, methyl palmitate, and docosyl docosanoate are preferred.

[0052] The aliphatic alcohol preferably has 20 or more carbon atoms, for example, behenyl alcohol, and the fatty acid preferably has 20 or more carbon atoms, for example, behenic acid.

[0053] The heat storage compound (B) can be appropriately selected depending on the desired phase transition temperature (heat retention temperature), and one type may be used alone, or two or more types may be used in combination.

[0054] <Porous inorganic compound (C)> The oil absorption of the porous inorganic compound (C) used in the present invention is 4.0 g / g or more, preferably 4.5 g / g or more and 10.0 g / g or less, more preferably 5.0 g / g or more and 9.5 g / g or less, and even more preferably 5.0 g / g or more and 9.0 g / g or less. When the oil absorption of the porous inorganic compound (C) is within the above range, a larger amount of the heat storage compound (B) can be retained, and therefore bleeding out of the heat storage compound (B) from the resin when the compound is formed into a molded article can be suppressed.

[0055] The average particle size of the porous inorganic compound (C) is preferably 1 μm or more and 100 μm or less, more preferably 1 μm or more and 50 μm or less, and even more preferably 2 μm or more and 30 μm or less. When the average particle size of the porous inorganic compound (C) is within the above range, the above-mentioned effects are further enhanced. The average particle size is a value measured using an apparatus and an analytical method suitable for measuring particle size, for example, a value measured by a laser diffraction / scattering method.

[0056] The porous inorganic compound (C) is not particularly limited as long as it is a porous inorganic compound having the above oil absorption amount, but from the viewpoint of having excellent heat resistance, for example, silica, alumina, carbon, etc. can be mentioned. These can be used alone or in combination of two or more. Among them, silica is preferred, and from the viewpoint of being able to further enhance the oil absorption effect, hydrophobic silica is more preferred.

[0057] Furthermore, the porous inorganic compound (C) is preferably one that is less likely to volatilize and ignite than the heat storage compound (B) alone when the temperature reaches or exceeds the melting point (melting peak temperature) of the heat storage compound (B) while holding the heat storage compound (B). Examples of such a preferred porous inorganic compound (C) include "AEROS" manufactured by THILIUM and "AIRICA" manufactured by Tokuyama Corporation.

[0058] <Composition> The content of each component in the resin composition of the present invention is such that the content of the heat storage compound (B) is 10 to 100 parts by mass and the content of the porous inorganic compound (C) is 1.5 to 20 parts by mass relative to 100 parts by mass of the thermoplastic resin (A).

[0059] The lower limit of the content of the heat storage compound (B) is preferably 40 parts by mass, more preferably 60 parts by mass, and the upper limit is preferably 95 parts by mass, more preferably 90 parts by mass. When the content of the heat storage compound (B) is within the above range, it is possible to exhibit heat and cold storage performance while maintaining processability and suppressing the possibility of bleed-out. Furthermore, the lower limit of the content of the porous inorganic compound (C) is preferably 4 parts by mass, more preferably 8 parts by mass, and the upper limit is preferably 19 parts by mass, more preferably 18 parts by mass.

[0060] In the thermoplastic resin (A), when the total amount of the thermoplastic resins (A1) and (A2) is taken as 100 parts by mass, the thermoplastic resin (A1) is used in an amount of 0 to 80 parts by mass, preferably 5 to 60 parts by mass, and more preferably 10 to 40 parts by mass, and the thermoplastic resin (A2) is used in an amount of 100 to 20 parts by mass, preferably 95 to 40 parts by mass, and more preferably 90 to 60 parts by mass. The thermoplastic resin (A1) is an optional component, but is preferably incorporated from the viewpoint that when the resin composition is heated and kneaded in a twin-screw extruder, strand-cut, and pelletized, the strands are cooled quickly and cutting defects are less likely to occur.

[0061] Furthermore, when the content of the porous inorganic compound (C) is 100 parts by mass, the content of the heat storage compound (B) is less than 700 parts by mass, preferably 100 parts by mass or more and 650 parts by mass or less, and more preferably 200 parts by mass or more and 600 parts by mass or less.

[0062] By ensuring that the content of each component satisfies the above conditions, when a molded article is formed, the heat storage compound (B) does not leak (bleed out) from the resin, a sufficient phase transition effect is obtained, and a molded article with excellent brittle resistance and light weight can be obtained.

[0063] <Optional ingredients> In addition to the above-described components (A) to (C), the resin composition of the present invention may contain optional additives such as slip agents, nucleating agents, fillers, antioxidants, weather stabilizers, colorants (including thermochromic materials), foaming agents, pigments, dyes, antistatic agents, and flame retardants, within the range that does not impair the effects of the present invention.

[0064] <Method of manufacturing resin composition> The method for producing the resin composition of the present invention includes a step of kneading the thermoplastic resin (A), the heat storage compound (B), the porous inorganic compound (C), and, if necessary, any optional components at a temperature of 150° C. or higher, preferably 152° C. or higher and 300° C. or lower, more preferably 154° C. or higher and 260° C. The kneading time is usually 1 to 20 minutes, preferably 1 to 10 minutes.

[0065] As the kneading device, a mixing roll, an intensive mixer (for example, a Banbury mixer or a kneader), a single-screw or twin-screw extruder, etc. can be used, but a non-open type device is preferred.

[0066] [Molded body] The molded article of the present invention is made from the resin composition of the present invention described above. Various known molding methods can be used. Specific examples include extrusion molding, press molding, injection molding, calendar molding, and blow molding. Furthermore, the molded article, such as a sheet, obtained by the molding method can be subjected to secondary processing such as thermoforming, or laminated with other materials to form a molded article. Furthermore, it can also be made into a granular molded article, such as a bead-shaped one, or a cylindrical molded article.

[0067] The uses of the molded article of the present invention are not particularly limited, and it is suitable for various well-known uses, such as automobile parts, civil engineering and building materials, electrical and electronic parts, daily necessities, sanitary products, films and sheets, foams, etc. In particular, it is useful as a material for steering wheels and instrument panels that become hot inside cars in the summer, interior wall materials, bathtub materials, wearable materials, apparel materials, shoes, various ice insulation materials, ice insulation containers, heat insulation materials, filling materials for ice insulation neck pillows, filling materials for pillows, and heat insulation containers. [Example]

[0068] The present invention will be explained in more detail below based on examples, but the present invention is not limited to these examples in any way.

[0069] [material] The components of the resin compositions produced in the examples and comparative examples are as follows: <Thermoplastic resin> A1-1: Prime Polymer "Neozex (registered trademark) 20201J" (linear medium-density polyethylene, density: 0.919 g / cm 3 , MFR (190℃, 2.16 kg load): 20 g / 10 min, Durometer D hardness (instantaneous value): 49) A1-2: Prime Polypro (registered trademark) F329RA manufactured by Prime Polymer Co., Ltd. (linear medium-density polyethylene, density: 0.900 g / cm 3 , MFR (190℃, 2.16kg load): 15g / 10min, Durometer D hardness (instantaneous value): 62) A2-1: Mitsui Chemicals, Inc.'s "Milastomer (registered trademark) 6010NST" (a cross-linked thermoplastic elastomer mainly composed of olefin-based rubber (EPT) and olefin-based resin (PP), density: 0.880 g / cm 3 Durometer A hardness (instantaneous value): 70, tensile elongation at break: 1000%, melting point (Tm): 160°C) A2'-2: "Tafmer (registered trademark) DF7350" manufactured by Mitsui Chemicals, Inc. (density: 0.870 g / cm 3 Durometer A hardness (instantaneous value): 70, tensile elongation at break: 1000%, melting point (Tm): 55°C) A'-1: Polyvinyl chloride (density: 1.2 g / cm 3 Durometer A hardness (instantaneous value): 70)

[0070] <Heat storage compounds (phase change materials)> B-1: Kao Corporation's "Exepar SS" (stearyl stearate, flash point: 258°C, ΔHm: 234 J / g) B-2: Kao Corporation's "Exepar MY-M" (myristyl myristate, flash point: 239°C, ΔHm: 229 J / g) B-3: NOF Corp. "Sperm Acetate" (cetyl myristate, flash point: 228°C, ΔHm: 241 J / g) B-4: NOF Corporation "Unistar M-2222SL" (docosyl docosanoate, flash point: 270°C, ΔHm: 224 J / g) B-5: TOENOL #2018-65 manufactured by Toei Chemical Co., Ltd. (methyl stearate, flash point: 172°C, ΔHm: 206 J / g)

[0071] <Porous inorganic materials> ·C-1: Hydrophobic silica (“AEROS” manufactured by THILIUM, oil absorption: 7g / g) ·C'-2: Activated carbide ("Sumirei" manufactured by Taniguchi Shokai Co., Ltd., oil absorption: 3.4g / g)

[0072] [Examples 1 to 5 and Comparative Examples 1 to 17] The amounts (parts by mass) of thermoplastic resin, heat storage compound (phase transition material), and porous inorganic material shown in Table 1 were kneaded for 5 minutes using a Labo Plastomill ("80C100" manufactured by Toyo Seiki Seisaku-sho, Ltd.) at a temperature of 150°C (240°C for Comparative Example 11 only) and a torque rotation speed of 30 rpm. After kneading, the kneaded product was promptly recovered. The resulting kneaded product was cut into small pieces with scissors, approximately 0.5 cm x 0.5 cm x 0.5 cm in size.

[0073] A Teflon (registered trademark) sheet and a mold were placed in that order on a stainless steel plate (hereinafter also referred to as "SUS plate"), and the cut material obtained above was spread in the holes of the mold. After the cut material was spread, the Teflon (registered trademark) sheet and the SUS plate were stacked in that order. The Teflon (registered trademark) sheet was used to prevent the kneaded material from sticking to the SUS plate during heat pressing. The molds used were 6.5 cm long, 6.5 cm wide, and three thicknesses (1 mm, 2 mm, and 5 mm).

[0074] The obtained laminate was hot-pressed for 5 minutes in a compression molding machine ("ASF-10" manufactured by Shinto Metal Industries Co., Ltd.) at a temperature of 150°C (240°C for Comparative Example 11 only) and a pressure of 10 MPa. It was then quickly transferred, sandwiched between SUS plates, to a compression molding machine ("NSF-37" manufactured by Shinto Metal Industries Co., Ltd.) and cooled at a pressure of 10 MPa for 5 minutes. After cooling, the SUS plates and Teflon (registered trademark) sheet were removed from the mold to obtain a hot-pressed sheet sample with the thickness listed in Table 1. The produced hot-pressed sheet samples were evaluated as follows.

[0075] <Bleed out> The heat-pressed sheet sample obtained above was sandwiched between clean paper on the top and bottom so that the 6.5 cm x 6.5 cm surface was parallel to the clean paper, and then sandwiched between SUS plates on the top and bottom. The sample was then heat-pressed for 5 minutes using a compression molding machine ("ASF-10" manufactured by Shinto Metal Industries Co., Ltd.) at a temperature of 100°C and a pressure of 10 MPa. After heat pressing, the heat-pressed sheet sample was quickly peeled off from the clean paper. The condition of the clean paper was checked, and if there were no marks on the area where the sheet was placed, it was evaluated as "Good: No leakage", and if there were marks, it was evaluated as "Poor: Leakage".

[0076] <Brittleness resistance> The heat-pressed sheet sample obtained above was cut to a length of 1.0 cm and a width of 6.5 cm to prepare test pieces for tensile testing. The tensile elongation of the test pieces was measured using a Tensilon universal testing machine (model: RTG-1225) at a tensile speed of 300 mm / min and a chuck distance of 50 mm. The tensile elongation value at the time the test piece broke was calculated as follows: elongation (%) = elongation value (mm) / chuck distance (mm). Based on the measured elongation, the test piece was evaluated according to the following criteria. 〇: Greater than 10% △: 5~10% ×: Less than 5%

[0077] <Heat retention> Approximately 5 mg of the heat-pressed sheet sample was cut out and measured using a differential scanning calorimeter (DSC) under the following conditions. Measurement device: X-DSC7000 (SII) Temperature: Start from -40°C, increase to 100°C, hold at 100°C for 1 minute, then decrease to -40°C Heating rate and cooling rate: 3°C / min Measurement atmosphere: Nitrogen Pretreatment: None Bread: Simple sealed bread

[0078] From the melting peak obtained by the measurement, information on the melting enthalpy ΔH (J / g) of the heat storage compound (phase change material) was obtained. Based on the obtained ΔH value, evaluation was made according to the following criteria. 〇: Greater than 50 J / g △: 25~50J / g ×: Less than 25 J / g

[0079] <Lightweight> The weight of the heat-pressed sheet sample obtained above was measured using a precision balance, and the value divided by the volume of the heat-pressed sheet obtained was used as the density. Based on the obtained density value, it was evaluated according to the following criteria. 〇:0.9g / cm 3 less than △: 0.9 g / cm 3 More than 1g / cm 3 less than ×:1g / cm 3 End

[0080] <Processability evaluation method> The above laminate was heat-pressed for 5 minutes in a compression molding machine ("ASF-10" manufactured by Shinto Metal Industries, Ltd.) at a temperature of 150°C and a pressure of 10 MPa. Then, while sandwiched between SUS plates, it was quickly transferred to a compression molding machine ("NSF-37" manufactured by Shinto Metal Industries, Ltd.) and cooled for 10 seconds at a pressure of 10 MPa. After cooling, the SUS plates and Teflon (registered trademark) sheet were removed from the mold, and the heat-pressed sheet was evaluated for recoverability. Cases where the sheet could be recovered without losing its shape were evaluated as "◎", cases where the sheet could be recovered with slight deformation were evaluated as "○", and cases where the sheet could not be recovered due to deformation were evaluated as "×".

[0081] <Overall rating> If there was no "x" in any of the evaluation results, the overall evaluation was rated as "O." If there was even one "x" or if the product could not be produced, the overall evaluation was rated as "x."

[0082] [Table 1]

[0083] The overall evaluation of the examples was "good", but the overall evaluation of the comparative examples was "poor".

[0084] <Evaluation of the effect of suppressing the rate of temperature rise / fall> The composition of Example 5 was evaluated for its effect of suppressing the rate of temperature increase and decrease due to the inclusion of a heat storage compound. The polystyrene foam container, heat press sheet, temperature data logger, and thermo-hygrostat used in the evaluation were as follows. The evaluation method will be described later.

[0085] <Styrofoam containers> Container type: "IC-4" (manufactured by Callux) Container size: Outer dimensions 192 x 210 x 198 mm, inner dimensions 152 x 152 x 160 mm <Heat press sheet sample (1)> Composition: same as in Example 5 -Production size: 15 x 15 cm, thickness 5 mm Number of sheets produced: 2 Preparation method: The same method as described in Example 1 was followed, except for the sample size. <Heat press sheet sample (2)> Composition: same as Comparative Example 11 -Production size: 15 x 15 cm, thickness 5 mm Number of sheets produced: 2 Preparation method: The method described in Example 1 was followed, except for the sample size. <Temperature data logger> "Super Thermochron" (KN Laboratories) ≪Constant temperature and humidity machine≫ "LHU-113" (manufactured by Espec Corporation)

[0086] Evaluation Method Two heat-pressed sheets (1) or two overlapping heat-pressed sheets (2) were placed at the bottom of a polystyrene foam container. To position the temperature data logger near the center of the polystyrene foam container's interior, a string approximately 10 cm long was prepared. One end of the string was attached to the polystyrene foam lid with cellophane tape, and the temperature data logger was then attached to the other end of the string with cellophane tape. The polystyrene foam lid was then attached to the polystyrene foam container and sealed with masking tape. The polystyrene foam container containing the heat-pressed sheets and temperature data logger was placed in a thermo-hygrostat and subjected to two temperature cycles: 35°C for 6 hours and 20°C for 6 hours. The temperature changes were compared. The results are shown in Figure 1.

[0087] It was found that in the polystyrene foam container equipped with heat press sheet (1), the rate of temperature rise was slower above 25°C, and the rate of temperature fall was slower below 23°C, compared to the polystyrene foam container equipped with heat press sheet (2).

[0088] From the above, it is believed that by using the product of the present invention containing a heat storage compound, the rate of temperature change can be suppressed, and by applying it to building materials (flooring and wall materials, for example), it is expected that the effect of making it easier to maintain a comfortable room temperature can be expected.

Claims

1. 100 parts by mass of thermoplastic resin (A); 10 to 100 parts by mass of a heat storage compound (B) (different from the component (A)) having a flash point of 155°C or higher; 1.5 to 20 parts by mass of a porous inorganic compound (C) having an oil absorption of 4.0 g / g or more; Including, The thermoplastic resin (A) is 0 to 80 parts by mass of a thermoplastic resin (A1) satisfying the following requirements (a-1) to (a-3); and 100 to 20 parts by mass of a thermoplastic resin (A2) that satisfies the following requirements (a-1) and (a-4) to (a-6) (the total amount of the thermoplastic resins (A1) and (A2) being 100 parts by mass), A resin composition in which the content of the heat storage compound (B) is less than 700 parts by mass when the content of the porous inorganic compound (C) is 100 parts by mass: (a-1) A density of 0.80 to 1.0 g / cm as measured in accordance with the method described in ASTM D 1505 ３ is in the range of (a-2) The melt flow rate (MFR) measured in accordance with the method described in ISO 1133 at 190°C under a load of 2.16 kg is in the range of 10 to 40 g / 10 min; (a-3) Durometer D hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90; (a-4) Durometer A hardness (instantaneous value) measured in accordance with the method described in ISO 7619 is in the range of 30 to 90; (a-5) The tensile elongation at break measured in accordance with the method described in JIS K6251 is in the range of 800 to 1200%; (a-6) The melting point (Tm) measured by a differential scanning calorimeter (DSC) is 100°C or higher.

2. The resin composition according to claim 1, wherein the content of the heat storage compound (B) is 60 to 95 parts by mass.

3. The resin composition according to claim 1 , wherein the heat storage compound (B) comprises a fatty acid ester.

4. The resin composition according to claim 1, wherein the heat storage compound (B) has a heat of crystalline fusion ΔHm of 150 J / g or more.

5. The resin composition according to claim 1, wherein the porous inorganic compound (C) comprises at least one compound selected from the group consisting of silica, alumina, and carbon.

6. The resin composition according to claim 1, wherein the porous inorganic compound (C) has an oil absorption of 4.5 g / g or more and 10.0 g / g or less.

7. The resin composition according to claim 1 , wherein the porous inorganic compound (C) comprises hydrophobic silica.

8. The resin composition according to claim 1, wherein the content of the porous inorganic compound (C) is 1.5 parts by mass or more and less than 14 parts by mass.

9. A molded article made of the resin composition according to any one of claims 1 to 8.

10. A building material comprising the resin composition according to any one of claims 1 to 8.

11. A pillow filler comprising the resin composition according to any one of claims 1 to 8.

12. A method for producing the resin composition according to any one of claims 1 to 8, comprising a step of kneading a thermoplastic resin (A), a heat storage compound (B), and a porous inorganic compound (C) at a temperature of 150°C or higher.

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