Hydrogenated product of block copolymer, resin composition, gel composition, cable filler, cable, cosmetic, lubricating oil, grease, and method for producing hydrogenated product of block copolymer

Abstract

The present invention provides: a hydrogenated product of a block copolymer which has a low glass transition temperature and exhibits suitable flexibility, rubber elasticity, and elongation properties even in a low temperature range; a resin composition; and a method for producing the hydrogenated product of a block copolymer. The hydrogenated product of a block copolymer contains a polymer block (A) including a structural unit derived from an aromatic vinyl compound and a polymer block (B) including a structural unit derived from a conjugated diene compound. The hydrogenated product of a block copolymer satisfies conditions (1) to (3) indicated below. (1) The structural unit derived from a conjugated diene compound in the polymer block (B) has a structural unit derived from butadiene and a structural unit derived from isoprene, and does not have any structural units derived from farnesene. (2) The glass transition temperature of the hydrogenated product of a block copolymer is -50ºC or less. (3) When the weight average molecular weight of the hydrogenated product of a block copolymer is denoted by x and the crystallization temperature is denoted by y (ºC), the hydrogenated product of a block copolymer satisfies 5.8x / 100,000 - y > 17.

Description

Hydrogenated block copolymer, resin composition, gel composition, cable filler, cable, cosmetic, lubricating oil, grease, and method for producing hydrogenated block copolymer

[0001] The present invention relates to a hydrogenated block copolymer, a resin composition, a gel composition, a cable filler, a cable, a cosmetic, a lubricating oil, a grease, and a method for producing the hydrogenated block copolymer.

[0002] Hydrogenated styrene-based elastomers, such as hydrogenated styrene-based elastomers, are known as hydrogenated block copolymers (hereinafter also referred to as "hydrogenated block copolymers") that contain a polymer block (A) composed of structural units derived from an aromatic vinyl compound and a polymer block (B) composed of structural units derived from a conjugated diene compound. Hydrogenated styrene-based elastomers are sometimes required to exhibit flexibility even at low temperatures. It is known that hydrogenated styrene-based elastomers containing a polymer block composed of structural units derived from a conjugated diene compound and a component with a low glass transition temperature (Tg), such as a hydrogenated product of butadiene or isoprene (hereinafter sometimes referred to as "hydrogenated product"), generally exhibit flexibility even at low temperatures. If the Tg of hydrogenated styrene-based elastomers could be further lowered, the hydrogenated styrene-based elastomers would be able to behave as rubber even at lower temperatures, thereby satisfying the demand for rubbers with better cold resistance. Furthermore, in applications where an elastomer is added to a resin to impart impact resistance or heat shock resistance to the resin, it is believed that by lowering the Tg of the elastomer, the physical properties of the resin, such as impact resistance and heat shock resistance, can be improved in the low temperature range.

[0003] When 1,4-bonded butadiene segments (hereinafter sometimes referred to as "1,4-butadiene segments") in a polymer are hydrogenated, the hydrogenated 1,4-butadiene segments have an ethylene structure. Therefore, if a polymer block consisting of structural units derived from a conjugated diene compound is composed solely of 1,4-butadiene segments, the polymer block is likely to crystallize and lose flexibility. Therefore, in existing styrene-based elastomers, the butadiene contains, for example, approximately 40% 1,2-bonded butadiene segments (hereinafter sometimes referred to as "1,2-butadiene segments") to increase the degree of vinylation, thereby preventing the majority of the polymer block consisting of structural units derived from a conjugated diene compound from crystallizing. However, because the Tg of hydrogenated 1,2-polybutadiene is higher than that of hydrogenated 1,4-polybutadiene, hydrogenated styrene-based elastomers containing a large amount of 1,2-butadiene segments have a high Tg, making it difficult to improve physical properties at low temperatures. Furthermore, the chain structure of the hydrogenated 1,4-butadiene segment is thought to partially crystallize. Since a long chain structure increases the crystallization temperature, it crystallizes at low temperatures, which tends to reduce the flexibility and impact resistance of the styrene-based elastomer. Furthermore, the mobility of the non-crystallized portion surrounding the crystalline portion is reduced by the influence of the low-mobility crystalline portion. Therefore, this crystallization of the butadiene segment is also thought to be related to the increase in Tg of the hydrogenated block copolymer. Therefore, there is a need for a new method that differs from the existing method of incorporating a large amount of 1,2-butadiene segments to improve properties at lower temperatures.

[0004] Hydrogenated block copolymers containing farnesene-derived monomer units are known (see, for example, Patent Document 1). Patent Document 1 describes that the hydrogenated block copolymers improve vibration damping, flexibility, rubber elasticity, and weather resistance. Patent Document 2 describes the addition of tetrahydrofuran (THF) during polymerization of isoprene and butadiene to obtain hydrogenated block copolymers having a styrene-hydrogenated (isoprene / butadiene)-styrene structure.

[0005] International Publication No. WO 2013 / 183570 International Publication No. WO 2017 / 159800

[0006] The hydrogenated block copolymer of Patent Document 1 does not take into consideration the improvement of properties such as flexibility, rubber elasticity, and mechanical strength in the temperature range around or below -40°C. Therefore, the hydrogenated block copolymer described in Patent Document 1 leaves room for improvement in this temperature range. Furthermore, using a large amount of farnesene tends to lead to increased costs and reduced mechanical strength. For this reason, a new method that does not require farnesene is needed. Patent Document 2 aims to achieve both flexibility and low-temperature impact resistance in a mixture obtained by adding a hydrogenated block copolymer to polypropylene. For this reason, a large amount of THF is added when producing the hydrogenated block copolymer of Patent Document 2, resulting in a large vinyl bond content in the resulting hydrogenated block copolymer. As a result, the Tg of the hydrogenated block copolymer is generally around -40°C, which is a relatively high Tg, and there is still room for improvement in improving properties at lower temperatures. Thus, there is a need for hydrogenated styrene-based elastomers that exhibit good properties such as flexibility, rubber elasticity, and mechanical strength at lower temperatures.

[0007] Furthermore, in gel compositions containing an oil component and a hydrogenated block copolymer, which are used in lubricating oils such as greases and engine oils, cosmetics, and the like, there is a demand for further improving the compatibility between the oil component and the hydrogenated block copolymer in order to further improve the properties, such as the thickening properties, of the compositions used in these applications.

[0008] Therefore, an object of the present invention is to provide a hydrogenated block copolymer having a low glass transition temperature and exhibiting good flexibility, rubber elasticity, and elongation properties even at low temperatures, a resin composition using the same, and a method for producing the hydrogenated block copolymer. Another object of the present invention is to provide a gel composition having excellent thickening properties by further improving the compatibility between an oil component and the hydrogenated block copolymer.

[0009] The present inventors have found that the above-mentioned problems can be solved by providing a hydrogenated block copolymer comprising a polymer block (A) containing a structural unit derived from an aromatic vinyl compound and a polymer block (B) containing a structural unit derived from a conjugated diene compound, wherein the structural unit derived from the conjugated diene compound in the polymer block (B) is specified, and have thus completed the present invention.

[0010] The present invention relates to the following items [1] to

[23] . [1] A hydrogenated block copolymer comprising a polymer block (A) containing structural units derived from an aromatic vinyl compound and a polymer block (B) containing structural units derived from a conjugated diene compound, the hydrogenated block copolymer satisfying the following conditions (1) to (3): (1) The structural units derived from the conjugated diene compound of the polymer block (B) contain structural units derived from butadiene and structural units derived from isoprene, and do not contain structural units derived from farnesene. (2) The glass transition temperature of the hydrogenated block copolymer is −50° C. or lower. (3) When the weight-average molecular weight of the hydrogenated block copolymer is x and the crystallization temperature of the hydrogenated block copolymer is y (° C.), the relationship 5.8x / 100,000−y>17 is satisfied. [2] The hydrogenated block copolymer according to item [1] above, wherein the content of the polymer block (A) in the hydrogenated block copolymer is 5 to 70% by mass. [3] The hydrogenated block copolymer according to [2] above, wherein the content of polymer block (A) in the hydrogenated block copolymer is 8 to 33 mass%. [4] The hydrogenated block copolymer according to any one of [1] to [3] above, wherein the vinyl bond content in polymer block (B) is 25 mol% or less. [5] The hydrogenated block copolymer according to [4] above, wherein the vinyl bond content in polymer block (B) is 18 mol% or less. [6] The hydrogenated block copolymer according to any one of [1] to [5] above, wherein the content of structural units derived from butadiene in polymer block (B) is 10 to 90 mol%. [7] The hydrogenated block copolymer according to [6] above, wherein the content of structural units derived from butadiene in polymer block (B) is 15 to 70 mol%. [8] The hydrogenated block copolymer according to [6] above, wherein the content of structural units derived from butadiene in polymer block (B) is 30 to 85 mol%. [9] The hydrogenated block copolymer according to any one of [1] to [8] above, wherein the hydrogenated block copolymer has a heat of crystallization of 20 J / g or less.

[10] The hydrogenated block copolymer according to any one of [1] to [9] above, wherein the weight-average molecular weight of the hydrogenated block copolymer is 30,000 to 500,000.

[11] The hydrogenated block copolymer according to any one of [1] to

[10] above, wherein the hydrogenation rate of the polymer block (B) is 90 mol % or more.

[12] The hydrogenated block copolymer according to any one of [1] to

[11] above, further satisfying the following condition (4): (4) Inverse gate decoupling. １３The linkage rate of 1,4-bonds of the hydrogenated butadiene, expressed as the proportion of the peak appearing at 29.2 ppm among peaks derived from 1,4-bonds of the hydrogenated butadiene obtained by C-NMR measurement, is less than 50%.

[13] The hydrogenated block copolymer according to any one of [1] to

[12] above, having a tensile break elongation of 300% or more as measured in accordance with JIS K 6251 (2017).

[14] The hydrogenated block copolymer according to any one of [1] to

[13] above, having a shear storage modulus G' at -40°C of 200 MPa or less as measured by a complex shear viscosity test at a frequency of 1 Hz in accordance with JIS K7244-10 (2005).

[15] A resin composition comprising, as component (a), a hydrogenated product of the block copolymer according to any one of the above items [1] to

[14] , and as component (b), one or more oil components selected from the group consisting of mineral oil, vegetable oil, and ethylene / α-olefin copolymer oligomer, wherein the content ratio (a) / (b) of component (a) to component (b) is 1 / 99 to 99 / 1 by mass.

[16] A resin composition comprising, as component (a), a hydrogenated product of the block copolymer according to any one of [1] to

[14] above, and, as component (c), one or more selected from the group consisting of polyethylene, polypropylene, styrene-based resin, polyphenylene ether, polyester resin, polycarbonate, polyacetal, polyamide, polyarylene sulfide, polyarylate, polyimide, polyether ether ketone, and liquid crystal polyester, wherein the content ratio (a) / (c) of component (a) to component (c) is 1 / 99 to 99 / 1 by mass.

[17] A gel composition comprising, as component (α), a hydrogenated product of the block copolymer according to any one of claims 1 to 14, and a base oil (β).

[18] A cable filler comprising the gel composition according to

[17] above.

[19] A cable comprising the gel composition according to

[17] above.

[20] A cosmetic comprising the gel composition according to

[17] above.

[21] A lubricating oil comprising the gel composition according to the above

[17] .

[22] A grease comprising the gel composition according to the above

[17] .

[23] A method for producing a hydrogenated block copolymer according to any one of [1] to

[14] above, comprising: a first step of conducting a polymerization reaction using at least an aromatic vinyl compound, butadiene, and isoprene as monomers in the presence of a polymerization initiator to obtain a block copolymer comprising a polymer block (A) containing structural units derived from the aromatic vinyl compound and a polymer block (B) containing structural units derived from the butadiene and the isoprene; and a second step of hydrogenating the block copolymer, wherein at least one of the following elements (i) to (vi) is performed in the first step: (i) the average feed rate when feeding the butadiene and isoprene to the reaction system is 50 kg / h / mol or less; (ii) the polymerization temperature is 55 to 80°C; and (iii) 0.3 mass% or less of a vinylating agent is added to the reaction system, based on the total mass of the raw material compounds. (iv) The time for feeding the butadiene and isoprene to the reaction system is set to 2.5 hours or more. (v) When the amount of polymerization initiator added is P (mol) and the amount of unreacted conjugated diene monomer is Q (mol), the ratio Q / P during polymerization of polymer block (B) is 100 or less. (vi) The mass ratio of the butadiene and isoprene when fed to the reaction system is varied depending on the timing of adding them to the reaction system.

[0011] The present invention provides a hydrogenated block copolymer having a low glass transition temperature and exhibiting good flexibility, rubber elasticity, and elongation properties even at low temperatures, a resin composition using the same, and a method for producing the hydrogenated block copolymer. The present invention also provides a gel composition having excellent thickening properties by further improving the compatibility between an oil component and the hydrogenated block copolymer.

[0012] Hereinafter, embodiments of the present invention will be described. The present invention also includes any embodiment in which the matters described in this specification are arbitrarily selected or arbitrarily combined. In this specification, preferred definitions can be selected arbitrarily, and combinations of preferred definitions can be considered more preferable. In this specification, the expression "XX to YY" means "XX or more and YY or less." In this specification, for preferred numerical ranges (e.g., ranges of content, etc.), lower and upper limits described in stages can be independently combined. For example, from the description "preferably 10 to 90, more preferably 30 to 60," the "preferable lower limit (10)" and the "more preferable upper limit (60)" can be combined to form "10 to 60."

[0013] [Hydrogenated Block Copolymer] The hydrogenated block copolymer according to the first embodiment of the present invention is a hydrogenated block copolymer comprising a polymer block (A) containing structural units derived from an aromatic vinyl compound and a polymer block (B) containing structural units derived from a conjugated diene compound, and satisfies the following conditions (1) to (3): (1) The structural units derived from the conjugated diene compound of polymer block (B) contain structural units derived from butadiene and structural units derived from isoprene, and do not contain structural units derived from farnesene. (2) The glass transition temperature of the hydrogenated block copolymer is −50° C. or lower. (3) When the weight-average molecular weight of the hydrogenated block copolymer is x and the crystallization temperature of the hydrogenated block copolymer is y (° C.), the relationship 5.8x / 100,000−y>17 is satisfied.

[0014] As specified by condition (1), the use of butadiene and isoprene as monomers for constituting polymer block (B) suppresses the continuous bonding of structural units derived from butadiene, making it easier to prevent crystallization of butadiene segments. Furthermore, not using farnesene as the monomer reduces the cost of the hydrogenated block copolymer and also makes it easier to prevent a decrease in the mechanical strength of the hydrogenated block copolymer. However, as a result of extensive research, the present inventors have found that in previously proposed hydrogenated block copolymers, the structural units derived from butadiene and the structural units derived from isoprene are unevenly distributed in the polymer block (B). They have found that reducing this uneven distribution can improve properties in the low-temperature range. Furthermore, as specified by condition (3), the present inventors have found that uneven distribution of structural units derived from butadiene is suppressed when the weight-average molecular weight x of the hydrogenated block copolymer and the crystallization temperature y (°C) of the hydrogenated block copolymer satisfy the relationship 5.8x / 100,000−y>17. In the case of a hydrogenated block copolymer having a large weight-average molecular weight, the amount of polymerization initiator used during production is generally small, so the amount of conjugated diene relative to the amount of polymerization initiator is large, and uneven distribution of structural units derived from butadiene is likely to occur. However, if the randomness of the structural units derived from butadiene and the structural units derived from isoprene is increased, the crystallization of the polymer block (B) is likely to be suppressed. Therefore, if the uneven distribution of the structural units derived from butadiene is suppressed, it is considered that the above condition (3) is satisfied.

[0015] Increasing the molecular weight of a block copolymer to enable its application in various applications also increases the molecular weight of polymer block (B), which is a polymer block other than the two ends of the block copolymer. Therefore, when a hydrogenated block copolymer is produced under conventional production conditions, the ethylene chain length after hydrogenation, based on the chain of structural units derived from butadiene, tends to be longer (i.e., the randomness tends to be lower). As a result, the crystallization temperature (Tc) of the hydrogenated block copolymer also tends to be higher. Therefore, by using Tc without taking into account the influence of molecular weight, the above condition (3) is made into a relational expression that reflects the presence of polymer block (B) exhibiting good low-temperature properties. A hydrogenated block copolymer satisfying condition (3) can be obtained, for example, by the procedure described below in the "Method for Producing Hydrogenated Block Copolymers" section.

[0016] By satisfying the above conditions (1) and (3), the condition specified in the above condition (2) is more likely to be satisfied in addition to the conditions (1) and (3), resulting in improved properties such as flexibility, impact resilience, and mechanical strength in the low-temperature range. Furthermore, when the hydrogenated block copolymer is used with an oil component to form a gel composition, compatibility between the hydrogenated block copolymer and the oil component is thought to be further enhanced, and good thickening properties are obtained when the gel composition is used in greases, cable fillers, cosmetics, and the like. To make it easier to satisfy the above condition (2), in the above condition (3), the value of "5.8x / 100,000-y" is preferably 18 or greater, more preferably 19 or greater, even more preferably 20 or greater, even more preferably 25 or greater, and particularly preferably 30 or greater. The upper limit of the value of "5.8x / 100,000-y" is not particularly limited, but is typically 200 or less, and may be 100 or less, or may be 50 or less. In this specification, the Tg of the hydrogenated block copolymer is measured using a differential scanning calorimeter (DSC). Specifically, the Tg is defined as the temperature at which a baseline shift occurs in a DSC curve created using DSC. More specifically, the Tg of the hydrogenated block copolymer is measured according to the method described in the Examples.

[0017] The hydrogenated product of the block copolymer preferably further satisfies the following condition (4), from the viewpoint of reducing the uneven distribution of the structural units derived from butadiene and the structural units derived from isoprene in the polymer block (B) and increasing the randomness of the structural units derived from butadiene and the structural units derived from isoprene: (4) Inverse gate decoupling １３ The conjugation rate of 1,4-bonds in the hydrogenated butadiene, which is expressed as the ratio of the peak appearing at 29.2 ppm among the peaks attributable to 1,4-bonds in the hydrogenated butadiene obtained by C-NMR measurement, is less than 50%. １３ It refers to the ratio of the peak appearing at 29.2 ppm to all peaks derived from 1,4-bonds of hydrogenated butadiene, obtained by C-NMR measurement. The linkage rate of 1,4-bonds of the hydrogenated butadiene is specifically measured by the method described in the Examples.

[0018] In the above condition (4), from the viewpoint of increasing the randomness of the structural units derived from butadiene and the structural units derived from isoprene, the conjugation rate of 1,4-bonds in the hydrogenated butadiene is preferably 49% or less, more preferably 48% or less, even more preferably 45% or less, and still more preferably 40% or less. There is no particular lower limit, but from the viewpoint of ease of production, it is, for example, 1% or more. In other words, the conjugation rate of 1,4-bonds in the hydrogenated butadiene is preferably 1% or more and less than 50%.

[0019] Furthermore, the hydrogenated block copolymer according to the second embodiment of the present invention is a hydrogenated block copolymer comprising a polymer block (A) containing structural units derived from an aromatic vinyl compound and a polymer block (B) containing structural units derived from a conjugated diene compound, and satisfies the following conditions (I) to (III): (I) The structural units derived from the conjugated diene compound of the polymer block (B) contain structural units derived from butadiene and structural units derived from isoprene, and preferably do not contain structural units derived from farnesene. (II) The glass transition temperature of the hydrogenated block copolymer is −50° C. or lower. (III) Inverse gate decoupling. １３ The linkage rate of 1,4-bonds of the hydrogenated butadiene, which is expressed by the ratio of the peak appearing at 29.2 ppm among peaks derived from 1,4-bonds of the hydrogenated butadiene obtained by C-NMR measurement, is less than 50%.

[0020] Inverse gate decoupling, as defined in condition (III) above １３By reducing the linkage rate of 1,4-bonds in hydrogenated butadiene, which is expressed as the proportion of the peak appearing at 29.2 ppm among peaks derived from 1,4-bonds in hydrogenated butadiene obtained by C-NMR measurement, below a specific rate, uneven distribution of butadiene-derived structural units is suppressed, the randomness of butadiene-derived structural units and isoprene-derived structural units is increased, and crystallization of polymer block (B) is more easily suppressed. Regarding condition (I), similar to the above-mentioned condition (1), by using butadiene and isoprene as monomers for constituting polymer block (B), continuous bonding of butadiene-derived structural units is suppressed, and crystallization of butadiene segments is more easily prevented. Furthermore, by satisfying the above-mentioned conditions (I) and (III), it becomes easier to satisfy the condition specified in the above-mentioned condition (II) in addition to conditions (I) and (III), and as a result, various properties such as flexibility, impact resilience, and mechanical strength in the low temperature range can be improved. Furthermore, when the hydrogenated block copolymer is used together with an oil component to form a gel composition, it is believed that the compatibility between the hydrogenated block copolymer and the oil component is further enhanced, and when the gel composition is used as a gel composition for grease, cable filler, cosmetics, etc., good thickening properties are obtained.

[0021] Each component constituting the hydrogenated block copolymer will be described below. Unless otherwise specified, the following description applies to both the first and second embodiments. The first and second embodiments may also be collectively referred to as "the present embodiment."

[0022] <Block Copolymer> The hydrogenated block copolymer is obtained by hydrogenating a block copolymer. The hydrogenated block copolymer according to an embodiment of the present invention comprises a polymer block (A) containing structural units derived from an aromatic vinyl compound and a polymer block (B) containing structural units derived from a conjugated diene compound. As defined by the above conditions (1) and (I), the structural units derived from the conjugated diene compound in the polymer block (B) have structural units derived from butadiene and structural units derived from isoprene. The polymer block (B) will be described in detail later.

[0023] Furthermore, as defined by the above conditions (2) and (II), the Tg of the hydrogenated block copolymer is −50° C. or lower. From the viewpoint of ensuring impact resistance and rubber elasticity at lower temperatures, the Tg of the hydrogenated block copolymer is preferably −53° C. or lower, more preferably −55° C. or lower, even more preferably −57° C. or lower, and even more preferably −59° C. or lower. There is no particular restriction on the lower limit of the Tg of the hydrogenated block copolymer, but from the viewpoint of ease of production, it is, for example, −80° C. In other words, the Tg of the hydrogenated block copolymer is preferably −80 to −50° C. The Tg of the hydrogenated block copolymer can be set within the above range, for example, by reducing the content of structural units derived from butadiene in polymer block (B) of the hydrogenated block copolymer to suppress crystallization of the hydrogenated butadiene.

[0024] (Polymer Block (A)) The polymer block (A) contains structural units derived from an aromatic vinyl compound (hereinafter sometimes abbreviated as "aromatic vinyl compound units"). From the viewpoint of mechanical properties, the content thereof is preferably more than 70 mol%, more preferably 80 mol% or more, even more preferably 85 mol% or more, still more preferably 90 mol% or more, particularly preferably 95 mol% or more, and may be substantially 100 mol%. In other words, the content of aromatic vinyl compound units in the polymer block (A) is preferably more than 70 mol% and 100 mol% or less.

[0025] Examples of the aromatic vinyl compound include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, β-methylstyrene, 2,6-dimethylstyrene, 2,4-dimethylstyrene, α-methyl-o-methylstyrene, α-methyl-m-methylstyrene, α-methyl-p-methylstyrene, β-methyl-o-methylstyrene, β-methyl-m-methylstyrene, β-methyl-p-methylstyrene, 2,4,6-trimethylstyrene, α-methyl-2,6-dimethylstyrene, α-methyl-2,4-dimethylstyrene, β-methyl-2,6-dimethylstyrene, β-methyl-2,4-dimethylstyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 2,6-dichlorostyrene, 2,4-dichlorostyrene, and α-chloro-o-chlorostyrene. , α-chloro-m-chlorostyrene, α-chloro-p-chlorostyrene, β-chloro-o-chlorostyrene, β-chloro-m-chlorostyrene, β-chloro-p-chlorostyrene, 2,4,6-trichlorostyrene, α-chloro-2,6-dichlorostyrene, α-chloro-2,4-dichlorostyrene, β-chloro-2,6-dichlorostyrene, β-chloro-2,4-dichlorostyrene, o-t-butylstyrene, m-t-butylstyrene, p-t-butylstyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-chloromethylstyrene, m-chloromethylstyrene, p-chloromethylstyrene, o-bromomethylstyrene, m-bromomethylstyrene, p-bromomethylstyrene, styrene derivatives substituted with a silyl group, indene, vinylnaphthalene, etc. These aromatic vinyl compounds may be used alone or in combination of two or more. Among these, from the viewpoint of the balance between production costs and physical properties, styrene, α-methylstyrene, p-methylstyrene, and mixtures thereof are preferred, and styrene is more preferred.

[0026] However, as long as the purpose and effects of the present invention are not hindered, polymer block (A) may contain less than 30 mol % of structural units derived from unsaturated monomers other than aromatic vinyl compounds (hereinafter, sometimes abbreviated as "other unsaturated monomer units"). Examples of such other unsaturated monomers include at least one selected from the group consisting of butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 1,3-hexadiene, isobutylene, methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β-pinene, 8,9-p-menthene, dipentene, methylenenorbornene, and 2-methylenetetrahydrofuran. When polymer block (A) contains such other unsaturated monomer units, the bonding form is not particularly limited and may be either random or tapered. The content of the structural units derived from the other unsaturated monomers in the polymer block (A) is preferably 10 mol % or less, more preferably 5 mol % or less, and even more preferably 0 mol %.

[0027] The hydrogenated block copolymer may have at least one polymer block (A). When the hydrogenated block copolymer has two or more polymer blocks (A), the polymer blocks (A) may be the same or different. In this specification, "different polymer blocks" means that the polymer blocks differ in at least one of the monomer units constituting the polymer blocks, the weight-average molecular weight, the stereoregularity, and, if multiple monomer units are present, the ratio of the monomer units and the copolymerization form (random, gradient, block). From the viewpoint of easily ensuring rubber elasticity, the hydrogenated block copolymer preferably has two polymer blocks (A).

[0028] The weight average molecular weight (Mw) of the polymer block (A) is not particularly limited, but from the viewpoints of mechanical strength and moldability, the weight average molecular weight of at least one polymer block (A) among the polymer blocks (A) contained in the hydrogenated block copolymer is preferably 3,000 to 60,000, more preferably 6,000 to 55,000, even more preferably 7,000 to 50,000, still more preferably 7,500 to 40,000, particularly preferably 8,000 to 35,000, and most preferably 8,000 to 30,000. From the viewpoint of fluidity and impact resistance, the weight average molecular weight of at least one polymer block (A) is preferably 3,000 to 60,000, more preferably 3,500 to 15,000, even more preferably 4,000 to 10,000, still more preferably 4,200 to 9,000, particularly preferably 4,300 to 8,000, and most preferably 4,500 to 7,000.

[0029] The "weight average molecular weight" in the present specification and claims is a weight average molecular weight calculated in terms of standard polystyrene obtained by gel permeation chromatography (GPC), and the detailed measurement method can be the same as that described in the Examples. In the case of a triblock copolymer having the A1-B-A2 structure, the total weight average molecular weight of the polymer blocks "A1" and "A2" is the weight average molecular weight of the block copolymer. １ The weight average molecular weight of the polymer block "A2" can be calculated by subtracting the weight average molecular weight of the deactivated initial polymer block "A1" from the total content of the polymer blocks "A1" and "A2" confirmed by H-NMR measurement and the weight average molecular weight of the initial polymer block "A1" that has been deactivated by GPC measurement.

[0030] The content of polymer block (A) in the hydrogenated block copolymer (when a plurality of polymer blocks (A) are present, the total content thereof) is preferably 5 to 70 mass%, more preferably 8 to 33 mass%, even more preferably 10 to 25 mass%, and still more preferably 15 to 22 mass%, from the viewpoint of ensuring impact resistance and rubber elasticity at lower temperatures. Furthermore, from the viewpoint of mechanical properties, the content is preferably 5 to 70 mass%, more preferably 15 to 50 mass%, even more preferably 20 to 40 mass%, and still more preferably 25 to 35 mass%. The content of polymer block (A) in the hydrogenated block copolymer is, １ This is a value determined by H-NMR measurement, and more specifically, is measured according to the method described in the Examples.

[0031] (Polymer Block (B)) In the hydrogenated product of the block copolymer according to the first embodiment, the polymer block (B) contains structural units derived from a conjugated diene compound (hereinafter, sometimes abbreviated as "conjugated diene compound units"). The conjugated diene compound units have structural units derived from butadiene and structural units derived from isoprene, but do not have structural units derived from farnesene. The Tg of polyethylene having a structure equivalent to that obtained by hydrogenating a 1,4-butadiene segment is said to be about -120°C. Therefore, if hydrogenated butadiene is used as the polymer block (B) consisting of structural units derived from a conjugated diene compound and crystallization can be further prevented, it is expected that a hydrogenated block copolymer with a low Tg can be obtained. Therefore, by using isoprene as a monomer for constituting the polymer block (B), continuous bonding of structural units derived from butadiene is suppressed, making it easier to prevent crystallization of butadiene, and as a result, it is easier to suppress crystallization of the polymer block (B). However, according to the studies of the present inventors, it has been found that if the structural units derived from butadiene and the structural units derived from isoprene are unevenly distributed in the polymer block (B), the bonding units derived from butadiene are likely to be continuously bonded, and the polymer block (B) is likely to crystallize. It has also been found that, as a result, the properties in the low temperature region cannot be sufficiently improved. Therefore, as specified in the above condition (3), when the weight-average molecular weight x of the hydrogenated block copolymer and the crystallization temperature y (°C) of the hydrogenated block copolymer satisfy a specific relationship, the uneven distribution of the structural units derived from butadiene is suppressed, the randomness of the structural units derived from butadiene and the structural units derived from isoprene is increased, and the crystallization of the polymer block (B) is easily suppressed.

[0032] Furthermore, in the hydrogenated block copolymer according to the second embodiment, the polymer block (B) contains conjugated diene compound units, and the conjugated diene compound units have structural units derived from butadiene and structural units derived from isoprene, and preferably do not have structural units derived from farnesene. As specified in the above condition (III), the hydrogenated block copolymer according to the second embodiment has a 1,4-bond sequence rate of the hydrogenated butadiene in the hydrogenated block copolymer within a specific range, thereby suppressing uneven distribution of the structural units derived from butadiene, increasing the randomness of the structural units derived from butadiene and the structural units derived from isoprene, and making it easier to suppress crystallization of the polymer block (B).

[0033] In the hydrogenated product of the block copolymer according to the first embodiment, the polymer block (B) may or may not contain structural units derived from conjugated diene compounds other than butadiene, isoprene, and β-farnesene, as long as the purpose and effects of the present invention are not hindered. From the viewpoint of easily achieving the desired performance, it is desirable that the polymer block (B) does not contain structural units derived from conjugated diene compounds other than butadiene, isoprene, and β-farnesene (i.e., it contains only structural units derived from butadiene and isoprene as conjugated diene compound units). From the viewpoint of flexibility and rubber elasticity, the total content of conjugated diene compound units in the polymer block (B) is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. There is no particular upper limit and it can be 100% by mass. In other words, the total content of conjugated diene compound units in the polymer block (B) is preferably 60 to 100% by mass. The total content of the conjugated diene compound units in polymer block (B) is, in terms of molar amount, preferably 30 mol% or more, more preferably 50 mol% or more, even more preferably 65 mol% or more, still more preferably 80 mol% or more, particularly preferably 90 mol% or more, and most preferably substantially 100 mol%. In other words, the total content of the conjugated diene compound units in polymer block (B) is preferably 30 to 100 mol%.

[0034] In the hydrogenated product of the block copolymer according to the first embodiment, the content of structural units derived from butadiene in the polymer block (B) is preferably 10 to 90 mol%, more preferably 15 to 70 mol%, and even more preferably 20 to 60 mol%, from the viewpoint of suppressing crystallization of the polymer block (B) and improving low-temperature properties. Furthermore, from the viewpoint of increasing the butadiene content to increase entanglement of hydrogenated block copolymers and thereby improving strength, the content is preferably 10 to 90 mol%, more preferably 30 to 85 mol%, even more preferably 40 to 80 mol%, and particularly preferably 45 to 75 mol%.

[0035] In the hydrogenated block copolymer according to the first embodiment, the mixing ratio (mass ratio) of the conjugated diene compounds [butadiene / isoprene] is not particularly limited as long as the effects of the present invention are not impaired, but is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 80 / 20, and even more preferably 30 / 70 to 70 / 30. The mixing ratio [butadiene / isoprene], expressed as a molar ratio, is preferably 6 / 94 to 96 / 4, more preferably 12 / 88 to 92 / 8, even more preferably 24 / 76 to 83 / 17, and particularly preferably 35 / 65 to 75 / 25.

[0036] In the hydrogenated product of the block copolymer according to the second embodiment, the polymer block (B) may or may not contain structural units derived from conjugated diene compounds other than butadiene and isoprene, as long as the purpose and effects of the present invention are not hindered. Examples of the conjugated diene compounds other than butadiene and isoprene include β-farnesene and myrcene. From the viewpoint of easily achieving the desired performance, it is desirable that the polymer block (B) does not contain structural units derived from conjugated diene compounds other than butadiene and isoprene. From this viewpoint and from the viewpoint of cost, it is desirable that the polymer block (B) does not contain structural units derived from β-farnesene.

[0037] In the hydrogenated product of the block copolymer according to the second embodiment, the preferred numerical ranges of the total content of conjugated diene compound units in the polymer block (B), the content of structural units derived from butadiene in the polymer block (B), and the mixing ratio of the conjugated diene compounds [butadiene / isoprene] (mass ratio, molar ratio) are the same as those explained for the polymer block (B) of the hydrogenated product of the block copolymer according to the first embodiment.

[0038] Furthermore, in the hydrogenated product of the block copolymer according to the first and second embodiments, the polymer block (B) may contain structural units derived from polymerizable monomers other than conjugated diene compounds, provided that the purpose and effects of the present invention are not hindered. In this case, the content of structural units derived from polymerizable monomers other than conjugated diene compounds in the polymer block (B) is preferably 70 mol% or less, more preferably 50 mol% or less, even more preferably 35 mol% or less, and particularly preferably 20 mol% or less. There is no particular restriction on the lower limit of the content of structural units derived from polymerizable monomers other than conjugated diene compounds, but it may be 0 mol%, 5 mol%, or 10 mol%. In other words, the content of structural units derived from polymerizable monomers other than conjugated diene compounds in the polymer block (B) is preferably 0 to 70 mol%.

[0039] Preferred examples of the other polymerizable monomer include aromatic vinyl compounds such as styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-t-butylstyrene, 2,4-dimethylstyrene, vinylnaphthalene, and vinylanthracene, as well as at least one compound selected from the group consisting of methyl methacrylate, methyl vinyl ether, N-vinylcarbazole, β-pinene, 8,9-p-menthene, dipentene, methylenenorbornene, 2-methylenetetrahydrofuran, 1,3-cyclopentadiene, 1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,3-cyclooctadiene, etc. Of these, styrene, α-methylstyrene, and p-methylstyrene are more preferred, and styrene is even more preferred.

[0040] When the polymer block (B) contains a structural unit derived from a polymerizable monomer other than a conjugated diene compound, the bonding form is not particularly limited and may be either random or tapered, but is preferably random.

[0041] The hydrogenated block copolymers according to the first and second embodiments need only have at least one polymer block (B). When the hydrogenated block copolymer has two or more polymer blocks (B), the polymer blocks (B) may be the same or different. When the polymer block (B) has two or more types of structural units, the bonding form thereof may be random, tapered, completely alternating, partially block-like, block, or a combination of two or more thereof. From the viewpoint of easily ensuring impact resistance and rubber elasticity at low temperatures, the hydrogenated block copolymer preferably has three or fewer polymer blocks (B), more preferably two or fewer polymer blocks (B). When the hydrogenated block copolymer is used for applications where rubber elasticity is important, the hydrogenated block copolymer still more preferably has one polymer block (B). When the hydrogenated block copolymer has two or more polymer blocks (B), the polymer blocks (B) may be the same or different.

[0042] There are no particular limitations on the bond form of the conjugated diene compound as long as it does not impair the objects and effects of the present invention. For example, the bond forms of butadiene and isoprene can be 1,2-bonds and 1,4-bonds in the case of butadiene, and 1,2-bonds, 3,4-bonds and 1,4-bonds in the case of isoprene. Only one type of these bond forms may be present, or two or more types may be present.

[0043] The content of the polymer block (B) in the hydrogenated block copolymer according to the first and second embodiments (when a plurality of polymer blocks (B) are present, the total content thereof) is preferably 30 to 95% by mass, more preferably 67 to 92% by mass, even more preferably 75 to 90% by mass, and still more preferably 78 to 85% by mass, from the viewpoint of ensuring impact resistance and rubber elasticity at lower temperatures. Furthermore, from the viewpoint of mechanical properties, the content is preferably 30 to 95% by mass, more preferably 50 to 85% by mass, even more preferably 60 to 80% by mass, and still more preferably 65 to 75% by mass. The content of the polymer block (B) in the hydrogenated block copolymer is, １ This is a value determined by H-NMR measurement, and more specifically, is measured according to the method described in the Examples.

[0044] (Vinyl Bond Content of Polymer Block (B)) Of the bonding forms of the structural units constituting the polymer block (B), the 1,2-bond derived from butadiene and the 1,2-bond and 3,4-bond derived from isoprene are defined as vinyl bonds, and the content of vinyl bond units is defined as the vinyl bond content. The vinyl bond content of the polymer block (B) is the ratio of the 3,4-bond units and 1,2-bond units in the isoprene structural units and the 1,2-bond units in the butadiene structural units to all structural units derived from butadiene and isoprene. In the hydrogenated block copolymers according to the first and second embodiments, the total vinyl bond content in the polymer block (B) is preferably 25 mol% or less, more preferably 20 mol% or less, even more preferably 18 mol% or less, still more preferably 16 mol% or less, and particularly preferably 14 mol% or less, from the viewpoint of lowering Tg. Furthermore, from the viewpoint of suppressing crystallization, it is preferably 3 mol% or more, more preferably 5 mol% or more, even more preferably 8 mol% or more, and particularly preferably 10 mol% or more. In other words, the vinyl bond content in the polymer block (B) is preferably 3 to 25 mol %. Here, the vinyl bond content can be determined by the method described in the Examples below. １ This is a value calculated by H-NMR measurement.

[0045] The total weight average molecular weight of the polymer blocks (B) in the hydrogenated block copolymers according to the first and second embodiments is, from the viewpoint of impact resistance at low temperatures, preferably 15,000 to 800,000, more preferably 20,000 to 200,000, even more preferably 30,000 to 150,000, particularly preferably 50,000 to 130,000, and most preferably 70,000 to 100,000 before hydrogenation. Furthermore, from the viewpoint of rubber elasticity and mechanical properties, the total weight average molecular weight of the polymer blocks (B) is, from the viewpoint of rubber elasticity and mechanical properties, preferably 15,000 to 800,000, more preferably 50,000 to 600,000, even more preferably 60,000 to 400,000, particularly preferably 65,000 to 350,000, and most preferably 70,000 to 300,000 before hydrogenation.

[0046] In the hydrogenated block copolymer, it is desirable that the polymer block (B) does not contain structural units derived from an aromatic vinyl compound. If the polymer block (B) contains structural units derived from an aromatic vinyl compound, the impact resistance and rubber elasticity at low temperatures may decrease.

[0047] (Bonding Mode Between Polymer Block (A) and Polymer Block (B)) The hydrogenated block copolymer is not limited in terms of the bonding mode between the polymer block (A) and the polymer block (B), and may be linear, branched, radial, or a combination of two or more of these. Among these, the bonding mode between the polymer block (A) and the polymer block (B) is preferably linear. Examples of such a bonding mode include, when polymer block (A) is represented by "A" and polymer block (B) is represented by "B," a diblock copolymer represented by A-B, a triblock copolymer represented by A-B-A or B-A-B, a tetrablock copolymer represented by A-B-A-B, a pentablock copolymer represented by A-B-A-B-A or B-A-B-A-B, and an (A-B)nX copolymer (X represents a coupling agent residue, and n represents an integer of 3 or greater). Among these, linear triblock copolymers or diblock copolymers are preferred, and A-B-A triblock copolymers are preferably used from the viewpoints of flexibility, ease of production, and the like. Herein, when polymer blocks of the same type are linearly bonded via a bifunctional coupling agent or the like, the entire bonded polymer blocks are treated as a single polymer block. Accordingly, including the above examples, polymer blocks that should strictly be expressed as Y-X-Y (X represents a coupling residue) are expressed as a whole as Y, unless it is particularly necessary to distinguish them from a single polymer block Y. In this specification, polymer blocks of this type containing coupling agent residues are treated as described above. Therefore, for example, a block copolymer containing a coupling agent residue and that should strictly be expressed as A-B-X-B-A (X represents a coupling agent residue) is expressed as A-B-A and treated as an example of a triblock copolymer.

[0048] The hydrogenation rate of the polymer block (B) is preferably 90 mol% or more. In other words, it is preferable that 90 mol% or more of the carbon-carbon double bonds in the polymer block (B) are hydrogenated. Here, the hydrogenation rate of the polymer block (B) is based on the amount of double bonds before hydrogenation. A high hydrogenation rate of the polymer block (B) results in excellent heat resistance and weather resistance. From the same viewpoint, the hydrogenation rate of the polymer block (B) is more preferably 91 mol% or more, more preferably 92 mol% or more, even more preferably 93 mol% or more, and particularly preferably 95 mol% or more. There is no particular restriction on the upper limit of the hydrogenation rate, but the upper limit may be substantially 100 mol%, 99.8 mol%, 99.5 mol%, or 99 mol%. In other words, the hydrogenation rate of the polymer block (B) is preferably 90 to 100 mol%. The hydrogenation rate is calculated by calculating the content of carbon-carbon double bonds in the structural units derived from the conjugated diene compound in the polymer block (B) after hydrogenation, as follows: １ The value was determined by H-NMR measurement, more specifically, the value was measured according to the method described in the Examples.

[0049] (Content of Polymer Block (A) and Polymer Block (B)) From the viewpoint of easily achieving the intended performance, the total content of polymer block (A) and polymer block (B) in the hydrogenated block copolymer is preferably 95% by mass or more, more preferably 98% by mass or more, even more preferably 99% by mass or more, and may be 100% by mass. Note that the hydrogenated product of the block copolymer preferably consists of only block copolymer (A) and block copolymer (B), but unavoidable impurity components may be contained.

[0050] (Weight Average Molecular Weight (Mw) of Hydrogenated Block Copolymer) The weight average molecular weight (Mw) of the hydrogenated block copolymer, as determined by gel permeation chromatography in terms of standard polystyrene, is not particularly limited, but is preferably 30,000 to 500,000 from the viewpoint of a balance between heat resistance and moldability. From the viewpoint of heat resistance, the lower limit of the weight average molecular weight (Mw) of the hydrogenated block copolymer is more preferably 60,000 or more, even more preferably 70,000 or more, particularly preferably 80,000 or more, even more particularly preferably 85,000 or more, and most preferably 90,000 or more. Furthermore, when moldability is important, the upper limit of the weight average molecular weight (Mw) of the hydrogenated block copolymer is more preferably 450,000 or less, even more preferably 400,000 or less, even more preferably 350,000 or less, particularly preferably 330,000 or less, more particularly preferably 320,000 or less, and most preferably 300,000 or less. Furthermore, the hydrogenated block copolymers according to the first and second embodiments of the present invention exhibit good flexibility, rubber elasticity, and elongation properties even at low temperatures, and are therefore preferably used as resin modifiers for improving the impact resistance of other resins. When the hydrogenated block copolymer is used as such a resin modifier, in order to facilitate obtaining superior impact resistance, the upper limit of the weight average molecular weight (Mw) of the hydrogenated block copolymer is preferably 250,000 or less, more preferably 200,000 or less, even more preferably 180,000 or less, even more preferably 150,000 or less, particularly preferably 130,000 or less, more particularly preferably 120,000 or less, and most preferably 110,000 or less. The weight average molecular weight of the hydrogenated block copolymer can be adjusted to the above range, for example, by adjusting the amount of monomer relative to the polymerization initiator.

[0051] The hydrogenated block copolymer may have one or more functional groups, such as a carboxyl group, a hydroxyl group, an acid anhydride group, an amino group, or an epoxy group, in the molecular chain and / or at the molecular terminal, or may have no functional groups, as long as the object and effects of the present invention are not impaired.

[0052] (Physical Properties of Hydrogenated Block Copolymer) The hydrogenated block copolymer may have a crystallization temperature of 0°C or lower, or may have no crystallization temperature. When the hydrogenated block copolymer has a crystallization temperature of 0°C or lower or no crystallization temperature, flexibility and rubber elasticity are improved. From the viewpoint of improving flexibility and rubber elasticity, if the hydrogenated block copolymer has a crystallization temperature, the crystallization temperature is more preferably −5°C or lower, even more preferably −10°C or lower, even more preferably −15°C or lower, still more preferably −20°C or lower, even more preferably −25°C or lower, and particularly preferably −30°C or lower. There is no particular restriction on the lower limit of the crystallization temperature, but it may be, for example, −70°C. In other words, if the hydrogenated block copolymer has a crystallization temperature, it is preferably −70 to 0°C. In this specification, the crystallization temperature of the hydrogenated block copolymer is measured by thermal analysis using DSC, specifically, by the method described in the Examples. The crystallization temperature of the hydrogenated block copolymer can be set as described above, for example, by adjusting the polymerization conditions of the diene monomer.

[0053] The heat of crystallization of the hydrogenated block copolymer may be 20 J / g or less, or may not have a crystallization temperature. When the heat of crystallization of the hydrogenated block copolymer is 20 J / g or less or does not have a crystallization temperature, flexibility and rubber elasticity are improved. From the viewpoint of improving flexibility and rubber elasticity, the heat of crystallization is more preferably 15 J / g or less, even more preferably 10 J / g or less, even more preferably 6 J / g or less, and particularly preferably no crystallization peak is present. The lower limit of the heat of crystallization is not particularly limited, but is, for example, 1 J / g. In other words, when a crystallization peak is present, the heat of crystallization of the hydrogenated block copolymer is preferably 1 to 20 J / g. Herein, the heat of crystallization of the hydrogenated block copolymer is measured by thermal analysis using DSC, specifically, by the method described in the Examples. The heat of crystallization of the hydrogenated block copolymer can be set as described above, for example, by adjusting the polymerization conditions of the diene monomer.

[0054] The tensile elongation at break of the hydrogenated block copolymer, measured in accordance with JIS K 6251 (2017), is preferably 300% or more, more preferably 400% or more, even more preferably 500% or more, and even more preferably 530% or more, from the viewpoint of ensuring good elongation properties. There is no particular upper limit to the tensile elongation at break, but from the viewpoint of ease of production, it is, for example, 1,000%. In other words, the tensile elongation at break of the hydrogenated block copolymer is preferably 300 to 1,000%. The tensile elongation at break is measured in more detail according to the method described in the Examples.

[0055] The shear storage modulus G' at -40°C of the hydrogenated block copolymer, measured by a complex shear viscosity test in accordance with JIS K7244-10 (2005) at a frequency of 1 Hz, is preferably 200 MPa or less, more preferably 100 MPa or less, even more preferably 50 MPa or less, still more preferably 25 MPa or less, particularly preferably 15 MPa or less, and most preferably 10 MPa or less, from the viewpoint of flexibility at low temperatures. There is no particular restriction on the lower limit of the shear storage modulus G', but from the viewpoint of mechanical strength, it is, for example, 0.1 MPa. In other words, the shear storage modulus G' at -40°C of the hydrogenated block copolymer is preferably 0.1 to 200 MPa. The shear storage modulus G' is measured in more detail according to the method described in the Examples.

[0056] The peak-top intensity of the loss tangent tanδ of a hydrogenated block copolymer measured in accordance with JIS K7244-10 (2005) under the conditions of a strain of 1%, a frequency of 1 Hz, a measurement temperature of -80 to 0°C, a heating rate of 3°C / min, and shear mode indicates that the greater the value, the better the flexibility at low temperatures. A value of 0.3 or higher indicates that sufficient flexibility at low temperatures can be obtained. The tanδ peak-top intensity is preferably 0.3 or higher, more preferably 0.5 or higher, and even more preferably 0.6 or higher. Furthermore, the peak-top temperature of the loss tangent tanδ of a hydrogenated block copolymer measured in accordance with JIS K7244-10 (2005) under the conditions of a strain of 1%, a frequency of 1 Hz, a measurement temperature of -80 to 0°C, a heating rate of 3°C / min, and shear mode is preferably -40°C or lower, more preferably -45°C or lower, and even more preferably -50°C or lower, from the viewpoint of ensuring sufficient flexibility and rubber elasticity in the low-temperature range. Although there is no particular restriction on the lower limit of the peak top temperature of the loss tangent tan δ, from the viewpoint of ease of production, it is, for example, −70°C. In other words, the peak top temperature of the loss tangent tan δ of the hydrogenated block copolymer is preferably −70 to −40°C. The peak top intensity of tan δ refers to the value of tan δ when the tan δ peak is at its maximum. The peak top temperature of tan δ refers to the temperature when the tan δ peak is at its maximum. The peak top temperature of tan δ and the peak top intensity of tan δ of the hydrogenated block copolymer are specifically measured by the methods described in the Examples. In order to set these values ​​within the above ranges, for example, the ratio of isoprene, which is the monomer for constituting the polymer block (B), can be adjusted.

[0057] [Resin Composition] A first embodiment of the resin composition of the present invention is a resin composition containing, as component (a), a hydrogenated product of the block copolymer described above, and, as component (b), one or more oil components selected from the group consisting of mineral oil, vegetable oil, and ethylene / α-olefin copolymer oligomer, wherein the mass ratio (a) / (b) of components (a) to (b) is 1 / 99 to 99 / 1. In one aspect, the total content of components (a) and (b) in the composition is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% by mass or more. Examples of mineral oils include paraffinic oil, naphthenic oil, and aromatic oil. Examples of vegetable oils include peanut oil and rosin.

[0058] By containing the hydrogenated block copolymer as component (a) and an oil component as component (b), the resin composition can have high strength and oil retention properties even in a low temperature range around −20° C. and below.

[0059] The content ratio (a) / (b) of component (a) to component (b) in the resin composition is, in terms of mass ratio, preferably 1 / 99 to 80 / 20, more preferably 3 / 97 to 70 / 30, even more preferably 4 / 96 to 60 / 40, and still more preferably 5 / 95 to 55 / 45, from the viewpoint of achieving both the mechanical properties and low-temperature characteristics of the resin composition.

[0060] A second embodiment of the resin composition of the present invention is a resin composition containing, as component (a), a hydrogenated product of the block copolymer, and as component (c), one or more selected from the group consisting of polyethylene, polypropylene, styrene-based resin, polyphenylene ether, polyester resin, polycarbonate, polyacetal, polyamide, polyarylene sulfide, polyarylate, polyimide, polyether ether ketone, and liquid crystal polyester, wherein the content ratio (a) of component (a) to component (c), (a) / (c), is 1 / 99 to 99 / 1 by mass. In one aspect, the total content of component (a) and component (c) in the resin composition is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, even more preferably 85% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% by mass or more.

[0061] By containing the hydrogenated block copolymer described above as component (a), the resin composition can have improved impact resistance and heat shock resistance in the low temperature range of around −20° C. and below, compared to component (c), which is the resin component before the addition of component (a).

[0062] The content ratio (a) / (c) of component (a) to component (c) in the resin composition is, in terms of mass ratio, preferably 1 / 99 to 50 / 50, more preferably 3 / 97 to 30 / 70, even more preferably 4 / 96 to 25 / 75, and still more preferably 5 / 95 to 20 / 80, from the viewpoint of achieving both the mechanical properties and low-temperature characteristics of the resin composition.

[0063] Furthermore, when a resin composition containing the above-mentioned components (a) and (c) is used in an application where impact resistance is important, it is more preferable that the resin composition further contains an ethylene-α-olefin copolymer rubber (d).

[0064] <Ethylene-α-olefin copolymer rubber (d)> The ethylene-α-olefin copolymer rubber (d) is a copolymer of ethylene and an α-olefin.

[0065] (α-Olefin) The α-olefin constituting the ethylene-α-olefin copolymer rubber (d) is not particularly limited, and examples thereof include α-olefins having 3 to 20 carbon atoms (hereinafter referred to as "C3 to C20"). The C3 to C20 α-olefins may have either a linear structure or a branched structure, and examples thereof include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-hexadodecene, 4-methyl-1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, diethyl-1-butene, trimethyl-1-butene, 3-methyl-1-pentene, and ethyl-1-pentene. , propyl-1-pentene, dimethyl-1-pentene, methylethyl-1-pentene, diethyl-1-hexene, trimethyl-1-pentene, 3-methyl-1-hexene, dimethyl-1-hexene, 3,5,5-trimethyl-1-hexene, methylethyl-1-heptene, trimethyl-1-heptene, dimethyloctene, ethyl-1-octene, methyl-1-nonene, vinylcyclopentene, vinylcyclohexene, vinylnorbornene, etc. These may be used alone or in combination of two or more. Among these, from the viewpoints of impact resistance and tensile elongation at break, C4 to C8 α-olefin comonomers are preferred, and at least one selected from the group consisting of propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene is more preferred. From the viewpoint of impact resistance, at least one selected from the group consisting of propylene, 1-butene, and 1-octene is even more preferred, with 1-octene being particularly preferred. On the other hand, from the viewpoint of moldability, at least one selected from the group consisting of propylene, 1-butene, and 1-octene is even more preferred, with propylene being particularly preferred. When the α-olefin constituting the ethylene-α-olefin copolymer rubber (d) is propylene and the component (c) is polypropylene, it is also a preferred embodiment to prepare the polypropylene, which is the component (c), using multistage polymerization.More specifically, one preferred embodiment of the present invention is to polymerize an isotactic polypropylene resin in the first stage of polymerization, polymerize an ethylene-propylene copolymer in the second stage, and then mix these.

[0066] The content of the α-olefin in the ethylene-α-olefin copolymer rubber (d) is not particularly limited, but is preferably 5 to 50 mass%, more preferably 20 to 45 mass%. When the content of the α-olefin in the ethylene-α-olefin copolymer rubber (d) is equal to or more than the lower limit, low-temperature hardening resistance and flexibility tend to be good, and when it is equal to or less than the upper limit, rigidity tends to be good.

[0067] Two or more kinds of ethylene-α-olefin copolymer rubbers may be used as the ethylene-α-olefin copolymer rubber (d). In this case, from the viewpoint of further improving impact resistance, tensile elongation at break, and rigidity, for example, two or more kinds of ethylene-α-olefin copolymer rubbers having different densities may be used in combination.

[0068] The melt flow rate (MFR) of the ethylene-α-olefin copolymer rubber (d) is not particularly limited, but is preferably 0.1 to 50 g / 10 min, more preferably 0.3 to 35 g / 10 min. When the melt flow rate (MFR) of the ethylene-α-olefin copolymer rubber (d) is equal to or higher than the lower limit, the processability tends to be good, and when it is equal to or lower than the upper limit, the mechanical properties tend to be good.

[0069] The molecular weight distribution (Mw / Mn; Mw is the weight average molecular weight, Mn is the number average molecular weight) of the ethylene-α-olefin copolymer rubber (d) is not particularly limited, but is preferably 1.3 to 5.0.

[0070] The density of the ethylene-α-olefin copolymer rubber (d) is not particularly limited, but is preferably 0.850 to 0.910 g / cm ３ , more preferably 0.855 to 0.885 g / cm ３When the density of the ethylene-α-olefin copolymer rubber (d) is equal to or higher than the lower limit, the rigidity tends to be good, and when it is equal to or lower than the upper limit, the impact resistance and tensile elongation at break tend to be good.

[0071] The catalyst used in preparing the ethylene-α-olefin copolymer rubber (d) is not particularly limited, and examples thereof include catalysts that can easily produce a highly molecular weight α-olefin copolymer under processing conditions (e.g., titanium-, metallocene-, or vanadium-based catalysts). These may be used alone or in combination of two or more. Among these, metallocene catalysts and titanium chloride are preferred from the viewpoint of stability of structure control.

[0072] The polymerization form of the ethylene-α-olefin copolymer rubber (d) is not particularly limited, and may be a random copolymer of ethylene and an α-olefin, a block copolymer of ethylene and an α-olefin, etc. Specific examples include, but are not limited to, "TAFMER (registered trademark)" manufactured by Mitsui Chemicals as a random copolymer rubber of ethylene and 1-butene, "ENGAGE (registered trademark)" manufactured by Dow as a random copolymer rubber of ethylene and 1-octene, and "INFUSE (registered trademark)" manufactured by Dow as a block copolymer rubber of ethylene and 1-octene.

[0073] The content of the ethylene-α-olefin copolymer rubber (d) in the resin composition is not particularly limited, but is preferably 1 to 50 parts by mass, more preferably 5 to 40 parts by mass, even more preferably 8 to 30 parts by mass, and particularly preferably 10 to 20 parts by mass, relative to 100 parts by mass of the component (c). When the content of the ethylene-α-olefin copolymer rubber (d) is equal to or greater than the lower limit, the impact resistance and tensile elongation at break tend to be good, and when it is equal to or less than the upper limit, the rigidity tends to be good.

[0074] Furthermore, when the resin composition contains component (a), component (c), and component (d), from the viewpoint of the balance between rigidity and impact resistance, it is more preferable that the resin composition contains polyethylene as component (c). The polyethylene is not particularly limited, and examples thereof include polyethylenes such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE). These may be used alone or in combination of two or more. Among these, polyethylenes such as medium-density polyethylene (MDPE) and high-density polyethylene (HDPE) are preferred, and high-density polyethylene (HDPE) is particularly preferred, from the viewpoint of obtaining higher rigidity while maintaining the impact resistance of the resin composition.

[0075] When the resin composition contains polyethylene, the content of polyethylene in the resin component of the resin composition is not particularly limited, but from the viewpoints of impact resistance, tensile elongation at break, and rigidity, it is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 22% by mass or less, particularly preferably 20% by mass or less, preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and particularly preferably 7% by mass or more.

[0076] The resin composition may contain, as resin components other than the components (a) to (d), hydrogenated resins such as hydrogenated coumarone-indene resins, hydrogenated rosin resins, hydrogenated terpene resins, and alicyclic hydrogenated petroleum resins, tackifying resins such as aliphatic resins composed of olefin and diolefin polymers, and other polymers such as hydrogenated polyisoprene, hydrogenated polybutadiene, butyl rubber, polyisobutylene, and polybutene, provided that the effects of the present invention are not impaired. When the resin composition contains resin components other than the components (a) to (d), the content of the components other than the components (a) to (d) in the composition is preferably 50% by mass or less, although this is not particularly limited. In this case, the content of the hydrogenated block copolymer according to the embodiment of the present invention in the composition is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% by mass or more, from the viewpoints of impact resistance and rubber elasticity at low temperatures.

[0077] <Additives> Examples of components other than the resin component that can be contained in the resin composition include, but are not limited to, additives such as antioxidants, ultraviolet absorbers, light stabilizers, heat-shielding materials, antiblocking agents, pigments, dyes, softeners, crosslinking agents, crosslinking aids, crosslinking accelerators, fillers, reinforcing materials, lubricants, antistatic agents, flame retardants, foaming agents, water repellents, waterproofing agents, electrical conductivity imparting agents, thermal conductivity imparting agents, electromagnetic wave shielding agents, fluorescent agents, and antibacterial agents. These additives may be used alone or in combination of two or more.

[0078] Examples of antioxidants include phenol-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants. Examples of ultraviolet absorbers that can be used include benzotriazole-based ultraviolet absorbers, hindered amine-based ultraviolet absorbers, and benzoate-based ultraviolet absorbers, as well as triazine-based compounds, benzophenone-based compounds, malonic acid ester compounds, and oxalic acid anilide compounds. Examples of light stabilizers include hindered amine-based light stabilizers. Examples of heat-shielding materials include glass containing heat-shielding particles with heat-shielding function and organic dye compounds with heat-shielding function. Examples of particles with heat-shielding function include oxide particles such as tin-doped indium oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, tin-doped zinc oxide, and silicon-doped zinc oxide, LaB ６Examples of suitable anti-blocking agents include inorganic particles having heat-shielding properties, such as lanthanum hexaboride particles. Examples of suitable organic dye compounds having heat-shielding properties include diimonium dyes, aminium dyes, phthalocyanine dyes, anthraquinone dyes, polymethine dyes, benzenedithiol ammonium compounds, thiourea derivatives, and thiol metal complexes. Examples of suitable anti-blocking agents include inorganic particles and organic particles. Examples of suitable inorganic particles include oxides, hydroxides, sulfides, nitrides, halides, carbonates, sulfates, acetates, phosphates, phosphites, organic carboxylates, silicates, titanates, borates, and hydrated compounds thereof, as well as composite compounds and natural mineral particles containing these elements, of Group IA, IIA, IVA, VIA, VIIA, VIIIA, IB, IIB, IIIB, and IVB elements. Examples of suitable pigments include organic pigments and inorganic pigments. Examples of organic pigments include azo pigments, quinacridone pigments, and phthalocyanine pigments. Examples of inorganic pigments include titanium oxide, zinc oxide, zinc sulfide, carbon black, lead pigments, cadmium pigments, cobalt pigments, iron pigments, chromium pigments, ultramarine, and Prussian blue. Examples of dyes include azo dyes, anthraquinone dyes, phthalocyanine dyes, quinacridone dyes, perylene dyes, dioxazine dyes, anthraquinone dyes, indolinone dyes, isoindolinone dyes, quinoneimine dyes, triphenylmethane dyes, thiazole dyes, nitro dyes, and nitroso dyes. Known softeners such as phosphate esters, low-molecular-weight polyethylene glycols, and hydrocarbon synthetic oils such as liquid polybutene, liquid polyisoprene or its hydrogenated products, and liquid polybutadiene or its hydrogenated products can be used. These may be used alone or in combination of two or more types.

[0079] Examples of the crosslinking agent include a radical generator, sulfur, and sulfur compounds. Examples of the radical generator include organic peroxides such as dialkyl monoperoxides such as dicumyl peroxide, di-t-butyl peroxide, and t-butylcumyl peroxide; diperoxides such as 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, bis(t-butyldioxyisopropyl)benzene, 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, and n-butyl-4,4-bis(t-butylperoxy)valerate; benzoyl group-containing peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, and 2,4-dichlorobenzoyl peroxide; monoacyl alkyl peroxides such as t-butylperoxybenzoate; percarbonates such as t-butylperoxyisopropyl carbonate; and diacyl peroxides such as diacetyl peroxide and lauroyl peroxide. These may be used alone or in combination of two or more. Among them, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and dicumyl peroxide are preferred from the viewpoint of reactivity. Examples of sulfur compounds include sulfur monochloride and sulfur dichloride. Other crosslinking agents that can be used include combinations of p-quinonedioxime and lead dioxide, and p,p'-dibenzoylquinonedioxime and trimead tetroxide.

[0080] As the crosslinking aid, known crosslinking aids can be used, and examples thereof include polyfunctional monomers such as trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, trimellitic acid triallyl ester, 1,2,4-benzenetricarboxylic acid triallyl ester, triallyl isocyanurate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, polyethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, divinylbenzene, glycerol dimethacrylate, and 2-hydroxy-3-acryloyloxypropyl methacrylate; stannous chloride, ferric chloride, organic sulfonic acid, polychloroprene, and chlorosulfonated polyethylene. One type of crosslinking aid may be used alone, or two or more types may be used in combination.

[0081] Examples of the crosslinking accelerator include thiazoles such as N,N-diisopropyl-2-benzothiazole-sulfenamide, 2-mercaptobenzothiazole, and 2-(4-morpholinodithio)benzothiazole; guanidines such as diphenylguanidine and triphenylguanidine; aldehyde-amine-based reaction products or aldehyde-ammonia-based reaction products such as butyraldehyde-aniline reaction product and hexamethylenetetramine-acetaldehyde reaction product; imidazolines such as 2-mercaptoimidazoline; thiocarbanilide, diethylurea, dibutylthiourea, and trimethylthiourea. thioureas such as diorthotolylthiourea; dibenzothiazyl disulfide; thiuram monosulfides or thiuram polysulfides such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, pentamethylenethiuram tetrasulfide; thiocarbamates such as zinc dimethyldithiocarbamate, zinc ethylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, tellurium diethyldithiocarbamate; xanthogenates such as zinc dibutylxanthogenate; zinc oxide, etc. The crosslinking accelerators may be used alone or in combination of two or more.

[0082] Examples of fillers include inorganic fillers such as talc, clay, mica, calcium silicate, glass, hollow glass spheres, glass fiber, calcium carbonate, magnesium carbonate, basic magnesium carbonate, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, zinc borate, dawsonite, ammonium polyphosphate, calcium aluminate, hydrotalcite, silica, diatomaceous earth, alumina, titanium oxide, iron oxide, zinc oxide, magnesium oxide, tin oxide, antimony oxide, barium ferrite, strontium ferrite, carbon fiber, activated carbon, hollow carbon spheres, calcium titanate, lead zirconate titanate, and silicon carbide; organic fillers such as wood flour and starch; conductive fillers such as carbon black, graphite, and carbon nanotubes; and metal fillers such as silver powder, copper powder, nickel powder, tin powder, copper fiber, stainless steel fiber, aluminum fiber, and iron fiber. Among these, talc, calcium carbonate, glass fiber, and carbon fiber are preferred, and talc and glass fiber are more preferred, from the viewpoint of the balance between rigidity and impact resistance. When a filler is contained, its content is not particularly limited, but is preferably 5 to 30 parts by mass, more preferably 10 to 25 parts by mass, and particularly preferably 15 to 23 parts by mass, relative to 100 parts by mass of the total resin components in the resin composition. If the filler content is equal to or greater than the lower limit, the rigidity and impact resistance tend to be good, and if it is equal to or less than the upper limit, the impact resistance and tensile elongation at break tend to be good.

[0083] There are no particular restrictions on the content of the additives contained in the resin composition, and it can be adjusted appropriately depending on the type of additive, etc. When the resin composition contains the additives, the content of the additives may be, for example, 50% by mass or less, 45% by mass or less, or 30% by mass or less, or 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more, relative to the total mass of the resin composition. In other words, the content of the additives is preferably 0.01 to 50% by mass relative to the total mass of the resin composition.

[0084] <Physical Properties of Resin Composition> (Tensile Strength) The tensile strength of the resin composition can be, for example, 0.10 MPa or more, 0.20 MPa or more, 0.30 MPa or more, or even 0.40 MPa or more. There is no particular upper limit to the tensile strength, but it is usually 50.0 MPa or less, and may be 1.0 MPa or less. In other words, the tensile strength of the resin composition is, for example, 0.10 to 50.0 MPa. By having the tensile strength of the resin composition within the above range, a resin composition with good mechanical properties can be obtained. Note that the tensile strength in this specification refers to a value measured according to a method in accordance with JIS K 6251 (2017), specifically, a value measured according to the measurement method described in the examples.

[0085] (Tensile Properties) The tensile properties of the resin composition include a tensile modulus of elasticity of, for example, 100 MPa or more, 350 MPa or more, 500 MPa or more, or even 700 MPa or more. There is no particular upper limit to the tensile modulus, but it is typically 2,000 MPa or less, and may be 1,000 MPa or less. The tensile properties of the resin composition include a yield stress of, for example, 5 MPa or more, 10 MPa or more, 15 MPa or more, or even 20 MPa or more. There is no particular upper limit to the yield stress, but it is typically 60 MPa or less, and may be 50 MPa or less. The tensile properties of the resin composition include a tensile elongation at break of, for example, 100% or more, 200% or more, 300% or more, or even 400% or more at 23°C. There is no particular upper limit to the tensile elongation at break of, for example, 1,000% or less, and may be 600% or less. Furthermore, the tensile elongation at break at -20°C can be, for example, 30% or more, 50% or more, 70% or more, or even 100% or more. There is no particular upper limit to the tensile elongation at break at -20°C, but it is usually 350% or less, and may be 300% or less. By having the tensile properties of the resin composition within the above range, a resin composition with good mechanical properties can be obtained. Note that the tensile properties in this specification refer to values ​​measured according to a method in accordance with JIS K 7161 (2014), specifically, values ​​measured according to the measurement method described in the examples.

[0086] The higher the oil retention rate of the resin composition, the better. For example, it is 50% or more, preferably 60% or more, and more preferably 70% or more, at both room temperature and low temperature. There is no particular upper limit to the oil retention rate, but it is usually 95% or less, and may be 90% or less. When the oil retention rate of the resin composition is within the above range, it can exhibit high stability during long-term storage. In this specification, the oil retention rate refers to a value calculated by placing a resin composition of a predetermined size at a predetermined temperature for a predetermined period of time and measuring the change in weight, and specifically refers to a value measured by the measurement method described in the examples.

[0087] The Charpy impact strength of the resin composition is, for example, 5 kJ / m ２ and 10 kJ / m or more. ２ Above, 15kJ / m ２ or more, and even 20 kJ / m ２ There is no particular upper limit to the Charpy impact strength, but it is usually 80 kJ / m ２ less than 70 kJ / m ２ The Charpy impact strength of the resin composition may be within the above range, making it less susceptible to fracture due to impact. Note that the Charpy impact strength in this specification refers to a value measured using an impact strength measuring device on a test piece prepared in accordance with JIS K 7111-1 (2012), and specifically refers to a value measured using the measurement method described in the examples.

[0088] The flexural strength of the resin composition can be, for example, 10 MPa or more, 15 MPa or more, 18 MPa or more, or even 20 MPa or more. There is no particular upper limit to the flexural strength, but it is usually 50 MPa or less, and may be 40 MPa or less. The flexural modulus of the resin composition can be, for example, 500 MPa or more, 700 MPa or more, 800 MPa or more, or even 900 MPa or more. There is no particular upper limit to the flexural modulus, but it is usually 1,500 MPa or less, and may be 1,200 MPa or less. By having the flexural strength and flexural modulus of the resin composition within the above ranges, a resin composition with good mechanical properties can be obtained. Note that the flexural strength and flexural modulus in this specification refer to values ​​measured in accordance with JIS K 7171 (ISO 178), specifically, values ​​measured by the measurement method described in the examples.

[0089] The melt flow rate (MFR) of the resin composition measured at 23°C under a load of 2.16 kg according to JIS K 7210:2014 can be, for example, 2.5 g / 10 min or more, 3.0 g / 10 min or more, 3.5 g / 10 min or more, or even 4.0 g / 10 min or more. There is no particular upper limit for the MFR, but it is usually 20 g / 10 min or less, and may be 10 g / 10 min or less. By having the MFR of the resin composition within the above range, good fluidity can be ensured. In this specification, MFR refers to a value measured according to JIS K 7210:2014, specifically, a value measured by the measurement method described in the examples.

[0090] [Gel Composition] The gel composition according to the embodiment of the present invention contains, as component (α), the hydrogenated product of the block copolymer according to the embodiment described above and a base oil (β). Below, the base oil (β), other components, the composition of the gel composition, the physical properties of the gel composition, etc. will be described.

[0091] <Base Oil (β)> Examples of the base oil (β) used in the gel composition according to this embodiment include mineral oil, synthetic oil, vegetable oil, and the like. Mineral oils include paraffinic mineral oils obtained by conventional refining methods such as solvent refining and hydrogenation refining; naphthenic mineral oils; waxes (gas-to-liquid wax) produced by the Fischer-Tropsch process; and mineral oils produced by isomerizing wax. Synthetic oils include hydrocarbon synthetic oils and ether synthetic oils. Examples of hydrocarbon synthetic oils include α-olefin oligomers or hydrogenated products thereof, such as polybutene, polyisobutylene, 1-octene oligomer, 1-decene oligomer, and ethylene-propylene copolymer; alkylbenzenes; alkylnaphthalenes; and the like. Ether synthetic oils include polyoxyalkylene glycols and polyphenyl ethers. Vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, and peanut oil. The mineral oils, synthetic oils, and vegetable oils used as the base oil (β) are classified into Groups I, II, III, IV, and V in the base oil classification of the American Petroleum Institute (API).

[0092] The base oil (β) may be one selected from mineral oil, synthetic oil, and vegetable oil, or may be a mixture of two or more mineral oils, two or more synthetic oils, two or more vegetable oils, or one or more mineral oils, synthetic oils, and vegetable oils. When the gel composition is used as part or all of the cable filler described below, mineral oil is preferred from the viewpoint of obtaining a gel composition having a viscosity suitable for cable fillers even when the blending ratio of the hydrogenated block copolymer as component (α) in the gel composition is low, and at least one selected from paraffinic mineral oils and naphthenic mineral oils is more preferred. Furthermore, paraffinic mineral oils are even more preferred from the viewpoint of improving the dropping point of the gel composition by making the polymer block (A) in the hydrogenated block copolymer less susceptible to plasticization. Furthermore, paraffinic mineral oils classified as Group II and Group III are preferred because they have low sulfur content and high saturates, and mineral oils classified as Group II are particularly preferred.

[0093] When the gel composition is used as part or all of a cosmetic product, the base oil (β) may be one selected from mineral oils, synthetic oils, and vegetable oils, or may be a mixture of two or more mineral oils, two or more synthetic oils, and two or more vegetable oils, or a mixture of one or more mineral oils, synthetic oils, and vegetable oils, but from the viewpoint of purity, mineral oils or synthetic oils of Groups III, IV, and V are preferred. Poly-α-olefins (abbreviated as PAO) classified in Group IV can also be used.

[0094] When the gel composition is used as part or all of a lubricating oil, the base oil (β) may be one selected from mineral oil, synthetic oil, and vegetable oil, or may be a mixture of two or more mineral oils, two or more synthetic oils, and two or more vegetable oils, or one or more mineral oils, synthetic oils, and vegetable oils, but mineral oil is preferred from the viewpoint of economy.

[0095] When the gel composition is used as part or all of a grease, the base oil (β) may be one selected from mineral oil, synthetic oil, and vegetable oil, or may be a mixture of two or more mineral oils, two or more synthetic oils, and two or more vegetable oils, or one or more mineral oils, synthetic oils, and vegetable oils. Base oils classified as Group I, Group II, and Group III are preferred because raw materials are readily available, and base oils classified as Group II and Group III are more preferred because they have low sulfur content and high saturated content. The base oils classified as Group II and Group III are more preferably mineral oils classified as Group II and Group III, and even more preferably mineral oils classified as Group II. Poly-α-olefins (abbreviated as PAO) classified as Group IV can also be used.

[0096] The kinematic viscosity at 40°C of the base oil (β) can be appropriately selected depending on the intended use of the resulting grease composition, but is preferably 5 to 1,000 mm ２ / s, more preferably 10 to 500 mm ２ / s, more preferably 20 to 200 mm ２ / s, particularly preferably 25 to 50 mm２ / s.

[0097] When the gel composition is used as part or all of a grease, the content of the base oil (β) is preferably 70 to 99 mass%, more preferably 75 to 99 mass%, even more preferably 80 to 99 mass%, and particularly preferably 85 to 99 mass%, based on 100 mass% of the total amount of the gel composition.

[0098] The base oil (β) preferably contains paraffin or a combination of paraffin and naphthene, and the mass ratio of paraffin to naphthene [paraffin / naphthene] is preferably 10 / 90 to 100 / 0. When the mass ratio of paraffin to naphthene is within the above range, the polymer block (A) in the hydrogenated block copolymer is less likely to be plasticized. When the gel composition according to this embodiment is used as part or all of a cable filler, from the viewpoint of improving the dropping point of the gel composition, the mass ratio of paraffin to naphthene [paraffin / naphthene] is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 90 / 10, even more preferably 30 / 70 to 90 / 10, even more preferably 40 / 60 to 90 / 10, even more preferably 50 / 50 to 90 / 10, even more preferably 60 / 40 to 90 / 10, and particularly preferably 60 / 40 to 80 / 20.

[0099] When the gel composition according to this embodiment is used as part or all of a cosmetic or lubricating oil, the base oil (β) preferably contains paraffin or a combination of paraffin and naphthene, and the mass ratio of paraffin to naphthene [paraffin / naphthene] is preferably 10 / 90 to 100 / 0, more preferably 20 / 80 to 100 / 0, even more preferably 30 / 70 to 100 / 0, even more preferably 40 / 60 to 100 / 0, even more preferably 50 / 50 to 100 / 0, even more preferably 60 / 40 to 100 / 0, and particularly preferably 70 / 30 to 100 / 0.

[0100] When the gel composition according to the present embodiment is used as part or all of a grease, from the viewpoints of the availability of the base oil (β), economic efficiency, and the oxidation stability of the grease, the mass ratio of paraffin to naphthene [paraffin / naphthene] is preferably 10 / 90 to 100 / 0, more preferably 20 / 80 to 100 / 0, even more preferably 30 / 70 to 100 / 0, even more preferably 40 / 60 to 100 / 0, even more preferably 50 / 50 to 100 / 0, even more preferably 60 / 40 to 100 / 0, even more preferably 70 / 30 to 100 / 0, and particularly preferably 70 / 30 to 90 / 10.

[0101] The viscosity index of the base oil (β) is preferably 70 or more, more preferably 80 or more, even more preferably 90 or more, particularly preferably 100 or more, and is preferably 150 or less, more preferably 145 or less, even more preferably 140 or less, even more preferably 135 or less, particularly preferably less than 120.

[0102] <Other Components> The gel composition according to the present embodiment may contain, as necessary, other components such as antioxidants, surfactants, pour point depressants, antifoaming agents, gelling agents, viscosity index improvers, thickeners, water absorbents, flame retardants, fillers, tackifying resins, thixotropic agents, petroleum waxes, metal deactivators, copper passivators, friction modifiers, rust inhibitors, detergent dispersants, extreme pressure agents, thickeners, etc. These additives may be used alone or in combination of two or more.

[0103] When the gel composition used as a grease contains a thickener, the content of the thickener in the gel composition can be adjusted as appropriate so that the worked penetration, mixing stability, oil separation rate, and aqueous water resistance of the grease fall within the desired ranges, but is preferably 1 to 40% by mass, more preferably 2 to 30% by mass, even more preferably 3 to 20% by mass, even more preferably 4 to 18% by mass, even more preferably 5 to 16% by mass, and particularly preferably 6 to 12% by mass. When the content of the thickener in the gel composition is within the above range, the grease tends to have an excellent balance between performance and economy.

[0104] <Content of Hydrogenated Block Copolymer> The content of the hydrogenated block copolymer as component (α) in the gel composition according to this embodiment is preferably 0.10 to 30.00 parts by mass, more preferably 0.25 to 27.00 parts by mass, even more preferably 0.50 to 25.00 parts by mass, even more preferably 0.75 to 23.00 parts by mass, even more preferably 0.75 to 20.00 parts by mass, and particularly preferably 0.75 to 18.00 parts by mass, relative to 100 parts by mass of the hydrogenated block copolymer and base oil (β) combined.

[0105] When the gel composition according to the present embodiment is used as a cable filler, the content of the hydrogenated block copolymer as component (α) in the gel composition is preferably 1 to 20 parts by mass, more preferably 2 to 18 parts by mass, even more preferably 4 to 16 parts by mass, even more preferably 6 to 14 parts by mass, and particularly preferably 7 to 13 parts by mass, relative to 100 parts by mass of the total of the hydrogenated block copolymer and the base oil (β). When the content of the hydrogenated block copolymer (a) in the gel composition is within the above range, it becomes easy to fill the gel composition as a cable filler into a protective tube or a cable during cable production. Furthermore, when the gel composition according to the present embodiment is used as a cosmetic, the content of the hydrogenated block copolymer as component (α) in the gel composition is preferably within the same range as when used as a cable filler. When the content of the hydrogenated block copolymer in the gel composition is within the above range, it becomes easy to fill the cosmetic composition into a container during cosmetic production or to use the cosmetic composition.

[0106] When the gel composition according to this embodiment is used as a lubricating oil, the suitable content of the hydrogenated block copolymer as component (α) in the gel composition is preferably 0.1 to 10.0 parts by mass, more preferably 0.2 to 5.0 parts by mass, even more preferably 0.3 to 4.0 parts by mass, even more preferably 0.4 to 3.0 parts by mass, and particularly preferably 0.5 to 2.0 parts by mass, per 100 parts by mass of the hydrogenated block copolymer and the base oil (β) combined. When the content of the hydrogenated block copolymer in the gel composition is within this range, the lubricating oil tends to have an excellent balance between performance and economy.

[0107] When the gel composition according to this embodiment is used as a grease, the suitable content of the hydrogenated block copolymer as component (α) in the gel composition is preferably 0.1 to 10.0 parts by mass, more preferably 0.2 to 5.0 parts by mass, even more preferably 0.2 to 4.5 parts by mass, even more preferably 0.3 to 4.0 parts by mass, even more preferably 0.5 to 4.0 parts by mass, even more preferably 1.0 to 4.0 parts by mass, even more preferably 1.5 to 4.0 parts by mass, and particularly preferably 1.8 to 3.5 parts by mass, per 100 parts by mass of the hydrogenated block copolymer and the base oil (β) combined. When the content of the hydrogenated block copolymer in the gel composition is within the above range, the grease tends to have an excellent balance between performance and economy.

[0108] <Content of Base Oil (β)> The content of the base oil (β) in the gel composition is preferably 70.00 parts by mass or more, more preferably 73.00 parts by mass or more, even more preferably 75.00 parts by mass or more, and particularly preferably 77.00 parts by mass or more, relative to 100 parts by mass of the total of the hydrogenated block copolymer as component (α) and the base oil (β), and the upper limit is preferably 99.90 parts by mass, more preferably 99.75 parts by mass, even more preferably 99.50 parts by mass, and particularly preferably 99.25 parts by mass.

[0109] When the gel composition according to this embodiment is used as a cable filler, the content of the base oil (β) in the gel composition is preferably 80 parts by mass or more, more preferably 83 parts by mass or more, and particularly preferably 86 parts by mass or more, per 100 parts by mass of the hydrogenated block copolymer as component (α) and the base oil (β) combined, and the upper limit is preferably 99 parts by mass or less, more preferably 97 parts by mass or less, and particularly preferably 94 parts by mass or less. When the content of the base oil (β) in the gel composition is within the above range, when the gel composition is used as a cable filler during cable production, the gel composition can be easily filled into a protective tube or a cable.

[0110] When the gel composition according to this embodiment is used as a cosmetic product, the content of the base oil (β) in the gel composition is preferably at least 80 parts by mass, more preferably at least 83 parts by mass, and particularly preferably at least 86 parts by mass, relative to 100 parts by mass of the hydrogenated block copolymer as component (α) and the base oil (β) combined, and the upper limit is preferably not more than 99 parts by mass, more preferably not more than 97 parts by mass, and particularly preferably not more than 94 parts by mass. When the content of the base oil (β) in the gel composition is within the above range, it becomes easier to fill the cosmetic composition into a container or to use it during the production of the cosmetic product.

[0111] When the gel composition according to this embodiment is used as a lubricating oil, the content of the base oil (β) in the gel composition is preferably 90 parts by mass or more, more preferably 95 parts by mass or more, and particularly preferably 96 parts by mass or more, per 100 parts by mass of the hydrogenated block copolymer as component (α) and the base oil (β), and the upper limit is preferably 99.9 parts by mass or less, more preferably 99.8 parts by mass or less, and particularly preferably 99.7 parts by mass or less. When the content of the base oil (β) in the gel composition is within the above range, the lubricating oil tends to have an excellent balance between performance and economy.

[0112] When the gel composition according to this embodiment is used as a grease, the content of the base oil (β) in the gel composition is preferably 90.0 parts by mass or more, more preferably 95.0 parts by mass or more, and particularly preferably 96.0 parts by mass or more, relative to 100 parts by mass of the total of the hydrogenated block copolymer (a) and the base oil (β), and the upper limit is preferably 99.9 parts by mass or less, more preferably 99.8 parts by mass or less, and particularly preferably 99.7 parts by mass or less. When the content of the base oil (β) in the gel composition is within the above range, the grease tends to have an excellent balance between performance and economy.

[0113] <Characteristics of Gel Composition> (Dropping Point) By using the hydrogenated block copolymer of this embodiment, the dropping point of the gel composition (the temperature at which the gel composition changes from semi-solid to liquid) can be, for example, 195°C or higher, and can also be 197°C or higher, 200°C or higher, or even 205°C or higher. There is no particular upper limit to the dropping point, but it is usually 400°C or lower, and may be 300°C or lower. When the dropping point of the gel composition is within the above range, when used as a cable filler, it is likely to exhibit the property that the gel composition as a filler will not flow out from the protective tube or cable over a wide range of temperatures, even if the protective tube is damaged. Furthermore, it is likely to be used as a gel composition with excellent shape retention in a wide range of applications other than cable filler. The dropping point in this specification refers to a value measured using a method in accordance with JIS K 2220:2013.

[0114] (Consistency) By adjusting the consistency of the gel composition containing the hydrogenated block copolymer of this embodiment to 360 to 430, when the gel composition according to this embodiment is used as a cable filler, it is possible to obtain a gel composition with an appropriate hardness that easily protects the inside. From the above viewpoint, the consistency of the gel composition is preferably 370 to 420, and more preferably 375 to 390. Note that the consistency in this specification refers to a value measured according to a method in accordance with JIS K 2220:2013.

[0115] (Viscosity) When the gel composition according to the embodiment of the present invention is used as a cable filler, the viscosity of the gel composition is 50 s. －１The viscosity under this shear rate condition is preferably 500 mPa·s or more, more preferably 1,000 mPa·s or more, even more preferably 2,000 mPa·s or more, even more preferably 3,000 mPa·s or more, even more preferably 3,500 mPa·s or more, and particularly preferably 4,000 mPa·s or more, from the viewpoint of preventing the gel composition serving as a filler from flowing out from the inside if the protective tube or cable is damaged, and is preferably 300,000 mPa·s or less, more preferably 50,000 mPa·s or less, even more preferably 30,000 mPa·s or less, and particularly preferably 20,000 mPa·s or less, from the viewpoint of easily filling the protective tube or cable with the gel composition during cable production. Note that the viscosity in this specification refers to a value measured with a rheometer.

[0116] When the gel composition according to this embodiment is used as a cosmetic product, the gel composition is －１ From the viewpoint of facilitating filling of the cosmetic composition into a container during the production of the cosmetic product or use, the viscosity under the shear rate condition is preferably from 500 mPa·s to 100,000 mPa·s, more preferably from 1,000 mPa·s to 50,000 mPa·s, even more preferably from 2,000 mPa·s to 40,000 mPa·s, even more preferably from 4,000 mPa·s to 30,000 mPa·s, still more preferably from 9,000 mPa·s to 30,000 mPa·s, and particularly preferably from 15,000 mPa·s to 25,000 mPa·s.

[0117] (Kinematic Viscosity) When the gel composition according to this embodiment is used as a lubricating oil, its kinematic viscosity at 40°C is 40 to 300 mm ２ / sec is preferable, and 50 to 150 mm ２ The kinematic viscosity at 100°C is preferably in the range of 3 to 30 mm / sec. ２ / sec is preferable, and 4 to 20 mm ２ When the kinematic viscosity is within the above range, fuel consumption can be reduced. The kinematic viscosity is a value measured in accordance with JIS K2283:2000.

[0118] (Worked Penetration) When the gel composition according to this embodiment is used as a grease, the worked penetration is preferably 85 to 475, more preferably 130 to 430, even more preferably 175 to 385, even more preferably 220 to 340, and particularly preferably 265 to 295. A low worked penetration can enhance the thickening effect. The worked penetration can be measured according to the method described in the examples.

[0119] (Increase in Consistency) When the gel composition according to this embodiment is used as a grease, the increase in consistency is preferably 50 or less, more preferably 45 or less, even more preferably 40 or less, and particularly preferably 35 or less. A small increase in consistency can improve shear stability. The increase in consistency is expressed as the difference between the blending stability and the worked consistency. Both the blending stability and the worked consistency can be measured according to the methods described in the examples.

[0120] (Oil Separation Rate) When the gel composition according to this embodiment is used as a grease, the oil separation rate is preferably 5.0% by mass or less, more preferably 4.0% by mass or less, and particularly preferably 3.0% by mass or less. A low oil separation rate can improve oil retention. In this specification, the oil separation rate can be measured according to the method described in the examples.

[0121] (Water Washing Resistance) When the gel composition according to this embodiment is used as a grease, its water washing resistance is preferably 20.0% by mass or less, more preferably 15.0% by mass or less, and particularly preferably 10.0% by mass or less. A low water washing resistance makes it possible to realize a gel composition that is less susceptible to softening and deterioration of adhesion due to moisture. In this specification, the water washing resistance can be measured according to the method described in the examples.

[0122] (Viscosity Index) When the gel composition according to the present embodiment is used as a lubricating oil, from the viewpoint of easily suppressing changes in viscosity due to temperature, the viscosity index is preferably 100 or more, more preferably 130 or more, and particularly preferably 150 or more. In this specification, the viscosity index can be measured according to the method described in the examples.

[0123] (High-temperature, high-shear viscosity) When the gel composition according to this embodiment is used as a lubricating oil, the high-temperature, high-shear viscosity thereof is preferably 1.5 mPa·s or more, more preferably 2.0 mPa·s or more, and particularly preferably 2.5 mPa·s or more, from the viewpoint of easily improving the protection of engines, etc. In this specification, the high-temperature, high-shear viscosity can be measured according to the method described in the examples.

[0124] (Kinematic viscosity after shear) When the gel composition according to this embodiment is used as a lubricating oil, the kinematic viscosity after shear is 5 mm ２ / sec or more is preferable, and 7 mm ２ / sec or more is more preferable, and 10 mm ２ / sec or more is particularly preferred. A high kinematic viscosity after shearing can result in a gel composition that is less susceptible to molecular scission due to shearing. In this specification, the kinematic viscosity after shearing can be measured according to the method described in the Examples.

[0125] (MRV Viscosity) When the gel composition according to this embodiment is used as a lubricating oil, its low-temperature pumping viscosity (MRV viscosity (-30°C)) is preferably 200,000 mPa·s or less, more preferably 180,000 mPa·s or less, and particularly preferably 150,000 mPa·s or less. A low MRV viscosity allows high performance to be exhibited even in low-temperature environments. In this specification, the MRV viscosity can be measured according to the method described in the examples.

[0126] [Cable Filler, Cable] A cable filler according to an embodiment of the present invention includes the gel composition according to the embodiment of the present invention described above, or may include only the gel composition. The gel composition according to an embodiment of the present invention has a viscosity suitable for use as a cable filler, allows the gel composition to be easily filled into a protective tube or cable during cable production, has a high dropping point, and exhibits the property of preventing the filler from flowing out from the inside over a wide range of temperatures even if the protective tube or cable is damaged, and can also prevent water from penetrating into the inside. Therefore, the gel composition according to an embodiment of the present invention is suitable as an internal cushioning material for cables such as optical fiber cables and electric wire cables.

[0127] A cable according to an embodiment of the present invention includes a gel composition according to an embodiment of the present invention, and is, for example, filled between a protective tube and a cable or around an optical fiber core in a cable with the gel composition. As described above, the gel composition of the present invention has sufficient elasticity to protect cables and the like, can be easily filled into a protective tube or a cable, has a viscosity that prevents the filler from flowing out from the inside if the protective tube or the cable is damaged, and can prevent water from entering the inside even if the protective tube or the cable is damaged, so that the cable can be particularly suitably used as an optical fiber cable.

[0128] [Cosmetics] Cosmetics according to embodiments of the present invention include a gel composition according to embodiments of the present invention, or may include only the gel composition. The gel composition according to embodiments of the present invention can be used in a cosmetic composition constituting a cosmetic according to embodiments of the present invention. Examples of cosmetics include hair makeup products such as shampoo, hair setting gel or lotion, blow-drying lotion, fixing and styling agent, etc.; skin makeup products such as foundation, eye shadow, blusher, concealer, compact powder, and makeup base, etc.; lip makeup products such as lipstick, liquid lipstick, and lip gloss, cleansing products such as facial cleanser and makeup remover, etc.; cream products such as petrolatum cream, hand cream, and ultrasound diagnostic cream, etc.

[0129] [Lubricant] The lubricant according to the embodiment of the present invention contains the gel composition according to the embodiment of the present invention, and may contain only the gel composition. The gel composition according to the embodiment of the present invention can be used in a lubricant composition constituting the lubricant according to the embodiment of the present invention. Examples of lubricants include engine oils, automatic transmission fluids, gear lubricants, and hydraulic oils.

[0130] [Grease] The grease according to the embodiment of the present invention contains the gel composition according to the embodiment of the present invention, and preferably contains only the gel composition. The gel composition according to the embodiment of the present invention can be used in the grease composition constituting the grease according to the embodiment of the present invention. Examples of the grease include grease for sliding members.

[0131] A sliding member to which the grease for sliding members is applied has the grease on its sliding surface, and the sliding surface slides in the presence of the grease composition. The sliding member is preferably one whose sliding surface is coated with the grease composition.

[0132] The sliding member preferably contains at least one selected from metal and resin. That is, the material of the sliding member is preferably at least one selected from metal and resin. The sliding member may be a metal sliding member, a resin sliding member such as plastic or rubber, or a sliding member manufactured using both metal and resin.

[0133] The sliding member is not particularly limited as long as it is used with grease applied to the sliding surface, and examples thereof include door panels, instrument panels, door locks, gears, outboard joints, inboard joints, universal joints, flexible joints, belt tensioners, fixing belts, pressure belts, pads, timing belts, conveyor belts, body seals for sunroofs, glass runs, weather strips, oil seals, packings, wiper blades, doctor blades, charging rollers, developing rollers, toner supply rollers, transfer rollers, heat rollers, pressure rollers, cleaning blades, Examples include paper feed rollers, transport rollers, intermediate transfer belts, intermediate transfer drums, heat belts, solenoid valves, electric valves, crankshafts, compressor shafts, slide bearings, oil pump gears, pistons, piston rings, piston pins, gaskets, guide rails, seatbelt buckles, brake pads, brake pad clips, brake shims, brake insulators, hinges, screws, pressure pads, air cylinders, electric cylinders, electric actuators, and other sliding members for automobiles, copiers, printers, and industrial machinery (including semiconductor manufacturing equipment and light emitting device / display manufacturing equipment).

[0134] The grease is also suitable as a grease composition for a rotating sliding member that performs rotational motion. The rotating sliding member is not particularly limited as long as it is accompanied by rotational motion, and examples thereof include bearings, gears, rotary shafts, belts, heat rollers, steering rollers, etc.

[0135] The applications of the sliding member are not particularly limited, and the sliding member can be used in, for example, home appliances, ships, railways, aircraft, machinery (including industrial production equipment), structures, automobile repair, automobiles, construction, building materials, textiles, leather, stationery, woodworking, furniture, miscellaneous goods, steel plates, cans, electronic substrates, electronic components, printing, and the like. Among these, the sliding member is useful for applications in automobiles and industrial machinery. That is, the sliding member is preferably an automobile part or an industrial machinery part. Similarly, the grease according to one aspect of the present invention described above can be suitably used for applications in automobiles and industrial machinery. Furthermore, as described above, the grease according to one aspect of the present invention is also useful for reducing noise, and therefore can be suitably used, for example, in mechanical devices or drive devices equipped with motors, and more specifically, can be suitably used for motor parts.

[0136] [Other Uses of Gel Composition] The gel composition according to the embodiment of the present invention can also be used as an asphalt modifier, an adhesive, a pressure-sensitive adhesive, a resin modifier, a compatibilizer, a sealant, a coating material, a molded product, a fiber / nonwoven fabric, a drilling fluid, and the like.

[0137] [Method for Producing Hydrogenated Block Copolymer] A method for producing a hydrogenated block copolymer according to an embodiment of the present invention comprises: a first step of conducting a polymerization reaction using at least an aromatic vinyl compound, butadiene, and isoprene as monomers in the presence of a polymerization initiator to obtain a block copolymer comprising a polymer block (A) containing structural units derived from the aromatic vinyl compound and a polymer block (B) containing structural units derived from the butadiene and the isoprene; and a second step of hydrogenating the block copolymer. In the first step, at least one of the following elements (i) to (vi) is implemented: (i) the average feed rate when feeding the butadiene and isoprene to the reaction system is set to 50 kg / h / mol or less; (ii) the polymerization temperature is set to 55 to 80°C; (iii) 0.3 mass% or less of a vinylating agent is added to the reaction system, relative to the total mass of the raw material compounds; and (iv) the time for feeding the butadiene and isoprene to the reaction system is set to 2.5 hours or more. (v) When the amount of polymerization initiator added is P (moles) and the amount of unreacted conjugated diene monomer is Q (moles), the ratio Q / P during polymerization of polymer block (B) is not more than 100. (vi) The mass ratio of butadiene and isoprene when fed to the reaction system is varied depending on the timing of their addition to the reaction system.

[0138] By carrying out at least one of the above elements (i) to (vi) in the first step, the randomness of the butadiene-derived structural units and the isoprene-derived structural units in the polymer block (B) can be easily increased, and the properties of the hydrogenated product of the block copolymer in the low temperature region can be improved.

[0139] Specifically, as defined in the above element (i), by preventing the average feed rates of butadiene and isoprene from being too high, it becomes easier to prevent the reaction of butadiene and isoprene from becoming biased.

[0140] Furthermore, as defined in the above element (ii), by appropriately increasing the polymerization temperature, it becomes easier to prevent the difference between the reaction rate of butadiene and the reaction rate of isoprene from becoming too large, which in turn makes it easier to increase the randomness of the structural units derived from butadiene in the polymer block (B).

[0141] Furthermore, as defined in the above element (iii), the use of a small amount of vinylating agent tends to reduce the difference in reaction rate between isoprene and butadiene, and tends to increase the randomness of the structural units derived from butadiene in the polymer block (B). In this case, from the viewpoint of easily avoiding a sudden increase in the vinyl bond amount in the resulting block copolymer due to the addition of the vinylating agent, it is preferable to use tetrahydrofuran as the vinylating agent used in element (iii).

[0142] Furthermore, as defined in the above element (iv), by setting the time for feeding butadiene and isoprene to the reaction system to 2.5 hours or longer, the influence of the difference in reaction rate between the two monomers is easily alleviated, and as a result, the randomness of the structural units derived from butadiene in the polymer block (B) is easily increased.

[0143] Furthermore, as defined in the above element (v), when the amount of polymerization initiator added is P (moles) and the amount of unreacted conjugated diene monomer is Q (moles), polymerization is carried out with Q / P set to 100 or less, thereby preventing the supply of a conjugated diene compound from causing an excessive increase in unreacted monomers in the reaction system. This prevents butadiene from reacting preferentially, and as a result, the randomness of the structural units derived from butadiene in the polymer block (B) is likely to increase.

[0144] Furthermore, as defined in the above element (vi), by varying the mass ratio of butadiene and isoprene when feeding them to the reaction system depending on the time of introduction into the reaction system, it is possible to delay the reaction of the component that tends to react preferentially. Specifically, by making the mass ratio of butadiene, which has a high reaction rate, small in the early stage of introduction into the reaction system and increasing it from the middle to late stages, the influence of the reaction rate with isoprene is mitigated, and as a result, it becomes easier to increase the randomness of the structural units derived from butadiene in the polymer block (B). The above first step and second step will be described below.

[0145] (First Step) In the first step, the block copolymer can be produced by, for example, solution polymerization, emulsion polymerization, or solid-phase polymerization. Among these, solution polymerization is preferred, and known methods such as ionic polymerization (e.g., anionic polymerization, cationic polymerization), and radical polymerization can be used. Among these, anionic polymerization is preferred. In the anionic polymerization, at least one compound selected from the group consisting of an aromatic vinyl compound and a conjugated diene compound is sequentially added in the presence of a solvent, an anionic polymerization initiator, and, if necessary, a Lewis base to obtain a block copolymer, and a coupling agent is added, if necessary, to cause the reaction. Here, from the viewpoint of easily mitigating the influence of the difference in reaction rate between butadiene and isoprene, it is preferred to feed the conjugated diene monomer such that the Q / P ratio during polymerization of the polymer block (B) is 100 or less, as defined in the above element (v), where P (mol) is the amount of polymerization initiator added and Q (mol) is the amount of unreacted conjugated diene monomer.

[0146] Examples of organolithium compounds that can be used as polymerization initiators for anionic polymerization include methyllithium, ethyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, pentyllithium, etc. Examples of dilithium compounds that can be used as polymerization initiators include naphthalenedilithium, dilithiohexylbenzene, etc.

[0147] Examples of the coupling agent include dichloromethane, dibromomethane, dichloroethane, dibromoethane, dibromobenzene, phenyl benzoate, methyldimethoxysilane, trimethoxysilane, tetramethoxysilane, methyltrimethoxysilane, isobutyltrimethoxysilane, and γ-glycidoxypropyltrimethoxysilane. The amounts of these polymerization initiators and coupling agents used are determined appropriately depending on the desired weight-average molecular weight of the target block copolymer. Typically, initiators such as alkyllithium compounds and dilithium compounds are preferably used in a proportion of 0.01 to 0.2 parts by mass per 100 parts by mass of the total of the monomers used in the polymerization, such as the aromatic vinyl compound and the conjugated diene compound. When a coupling agent is used, it is preferably used in a proportion of 0.001 to 0.8 parts by mass per 100 parts by mass of the total of the monomers.

[0148] The solvent is not particularly limited as long as it does not adversely affect the anionic polymerization reaction, and examples thereof include aliphatic hydrocarbons such as cyclohexane, methylcyclohexane, n-hexane, and n-pentane; and aromatic hydrocarbons such as benzene, toluene, and xylene. The polymerization reaction is typically carried out at a temperature of 0 to 100°C, preferably 10 to 70°C, for typically 0.5 to 50 hours, preferably 1 to 30 hours. From the viewpoint of easily mitigating the influence of the difference in reaction rate between butadiene and isoprene, as specified in the above element (ii), the polymerization temperature is preferably 55 to 80°C, more preferably 57 to 75°C, and even more preferably 58 to 72°C. From the same viewpoint, as specified in the above element (iv), the time for feeding butadiene and isoprene to the reaction system is 2.5 hours or more, more preferably 3 hours or more, even more preferably 4 hours or more, and even more preferably 5 hours or more.

[0149] Furthermore, the content of 3,4-bonds and 1,2-bonds (vinyl bond amount) in the polymer block (B) can be increased by adding a Lewis base as a cocatalyst (vinylating agent) during polymerization. Examples of the Lewis base include ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, and 2,2-di(2-tetrahydrofuryl)propane (DTHFP); glycol ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether; amines such as triethylamine, N,N,N',N'-tetramethylenediamine, N,N,N',N'-tetramethylethylenediamine (TMEDA), and N-methylmorpholine; and metal salts such as sodium or potassium salts of aliphatic alcohols, such as sodium t-butylate, sodium t-amylate, and sodium isopentylate, or dialkylsodium cyclohexanolate, or sodium or potassium salts of alicyclic alcohols, such as sodium mentholate. Among the above Lewis bases, tetrahydrofuran and DTHFP are preferred from the viewpoints of impact resistance and thermal stability, and tetrahydrofuran is more preferred from the viewpoint of mitigating the effect of the difference in reaction rate between butadiene and isoprene. These Lewis bases may be used alone or in combination of two or more.

[0150] The amount of Lewis base added is determined by the extent to which the vinyl bond content of the butadiene-derived structural units and isoprene-derived structural units constituting the polymer block (B) is controlled. Therefore, while there are no strict limitations on the amount of Lewis base added, it is generally preferred to use a range of 0.1 to 1,000 mol, preferably 1 to 100 mol, per mol of lithium contained in the alkyllithium compound or dilithium compound used as the polymerization initiator. Furthermore, when a vinylating agent is used for the purpose of mitigating the effects of the difference in reaction rate between butadiene and isoprene, the amount used is, as defined in element (c) above, preferably 0.3% by mass or less, more preferably 0.25% by mass or less, even more preferably 0.2% by mass or less, even more preferably 0.15% by mass or less, particularly preferably 0.1% by mass or less, and most preferably 0.05% by mass or less, relative to the total mass of the raw material compounds. The lower limit of the amount of vinylating agent used may be, for example, 0.01% by mass or more, or 0.02% by mass or more. Of course, the polymerization reaction can be carried out without adding a Lewis base. In particular, from the viewpoint of facilitating the reduction of the glass transition temperature of the hydrogenated product of the block copolymer, it is preferable not to add a Lewis base in the first step.

[0151] Butadiene and isoprene may be supplied to the reaction system at the same mass ratio at all times, or may be supplied at different mass ratios depending on the timing of supply, as defined in the above element (vi). In the former case, control in the production of the block copolymer is easy, and in the latter case, it is easy to adjust the difference in the reaction rate of the monomers.

[0152] In the polymerization of polymer block (B) in the first step, the average feed rate of the conjugated diene compound (hereinafter sometimes referred to as the "average diene feed rate") is, as defined in element (i) above, preferably 50 kg / h / mol or less, more preferably 30 kg / h / mol or less, even more preferably 20 kg / h / mol or less, and still more preferably 15 kg / h / mol or less per mole of active terminal, from the viewpoint of ensuring the randomness of the structural units derived from butadiene and the structural units derived from isoprene in polymer block (B). There is no particular restriction on the lower limit of the average diene feed rate, but from the viewpoint of productivity, it is, for example, 0.1 kg / h / mol per mole of active terminal. In other words, in the polymerization of polymer block (B) in the first step, the average feed rate of the conjugated diene compound is preferably 0.1 to 50 kg / h / mol. In this specification, the term "average diene feed rate" refers to the value obtained by dividing the mass of the entire conjugated diene compound by the time required to feed the entire conjugated diene compound (diene feed time) and the number of moles of active ends, and is expressed in units of kg / h / mol. The number of moles of active ends is the value obtained by dividing the amount (g) of monomers used in the polymerization of polymer block (A) by the weight-average molecular weight of polymer block (A).

[0153] In the first step, after polymerization, an active hydrogen compound such as an alcohol, a carboxylic acid, or water is added to terminate the polymerization reaction.

[0154] (Second Step) In the second step, for example, a hydrogenated copolymer is obtained by carrying out a hydrogenation reaction (hydrogenation reaction) in an inert organic solvent in the presence of a hydrogenation catalyst. The hydrogenation reaction can be carried out at a hydrogen pressure of typically 0.1 to 20 MPa, preferably 0.5 to 15 MPa, and more preferably 0.5 to 5 MPa, a reaction temperature of typically 20 to 250°C, preferably 50 to 180°C, and more preferably 70 to 180°C, and a reaction time of typically 0.1 to 100 hours, and preferably 1 to 50 hours. Examples of hydrogenation catalysts that can be used to carry out the hydrogenation reaction of polymer block (B) while suppressing nuclear hydrogenation of the aromatic vinyl compound include Raney nickel; Ziegler catalysts composed of a combination of a transition metal compound with an alkylaluminum compound, an alkyllithium compound, or the like; and metallocene catalysts. From the same viewpoint as above, among these, Ziegler catalysts are preferred, Ziegler catalysts comprising a combination of a transition metal compound and an alkylaluminum compound are more preferred, and Ziegler catalysts comprising a combination of a nickel compound and an alkylaluminum compound (Al / Ni-based Ziegler catalysts) are even more preferred.

[0155] The hydrogenated block copolymer thus obtained can be obtained by pouring the polymerization reaction liquid into methanol or the like, stirring, filtering, and then heating or drying under reduced pressure, or by pouring the polymerization reaction liquid into hot water together with steam to remove the solvent by azeotropy (so-called steam stripping), followed by heating or drying under reduced pressure.

[0156] [Method for Producing Resin Composition] The method for producing the resin composition is not particularly limited, and known methods can be used. For example, the resin composition can be produced by mixing the hydrogenated product of the block copolymer (component (a)) and the oil component (component (b)) using a mixer such as a Henschel mixer, V-blender, ribbon blender, tumbler blender, or conical blender, or by mixing and then melt-kneading using a single-screw extruder, twin-screw extruder, kneader, or the like. Even when the resin composition contains additives such as those described above in addition to components (a) to (d), the resin composition can be produced by mixing the additives in addition to components (a) and (b) using the mixer described above, or by mixing and then melt-kneading using the apparatus described above. Resin compositions containing components (a) and (b), and optionally, component (d), can also be produced in the same manner.

[0157] [Method for Producing Gel Composition] The gel composition according to the embodiment of the present invention can be produced using a production method well known in the art. For example, it can be produced by mixing the hydrogenated block copolymer as component (α), the base oil (β), and other components as needed. The mixing can be carried out using a well-known mixing device. More specifically, the gel composition can be produced by mixing the hydrogenated block copolymer, the base oil (β), and other components as needed at 100 to 200°C under air or nitrogen for 0.1 to 10 hours, and then cooling under vacuum as needed.

[0158] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples in any way.

[0159] [Example 1] <Production of hydrogenated block copolymer TPE-1> A pressure vessel that had been purged with nitrogen and dried was charged with 50 kg of cyclohexane (solvent) dried over molecular sieves A4 and 0.137 kg of a 10.5% by mass cyclohexane solution of sec-butyllithium as an anionic polymerization initiator (effective amount of sec-butyllithium added: 14.4 g). After heating the pressure vessel to 70°C, 1.1 kg of styrene (1) was added and polymerized for 30 minutes, followed by the addition of 0.012 kg of tetrahydrofuran as a Lewis base. 4.5 kg of butadiene and 5.7 kg of isoprene were added over 5 hours (i.e., a diene feed time of 5 hours, an average diene feed rate of 9 kg / h / mol), followed by polymerization for 1 hour. Thereafter, 1.1 kg of styrene (2) was added and polymerized for 30 minutes. Methanol was then added to terminate the reaction, yielding a reaction solution containing a polystyrene-polybutadiene / polyisoprene-polystyrene triblock copolymer. A Ziegler hydrogenation catalyst formed from nickel octylate and trimethylaluminum was added to the reaction solution under a hydrogen atmosphere, and the mixture was reacted for 5 hours under conditions of a hydrogen pressure of 1 MPa and 80° C. After allowing the reaction solution to cool and release the pressure, the catalyst was removed by washing with water, and the mixture was dried in vacuo to obtain a hydrogenated product of a polystyrene-polybutadiene / polyisoprene-polystyrene triblock copolymer (TPE-1).

[0160] Examples 2 to 6 Production of Hydrogenated Block Copolymers TPE-2 to TPE-6 Hydrogenated polystyrene-polybutadiene / polyisoprene-polystyrene triblock copolymers (hydrogenated block copolymers TPE-2 to TPE-6) were produced in the same manner as in Example 1, except that the raw materials and their amounts were as shown in Table 1. However, for TPE-6, the polymerization temperature was 60°C, the diene feed time was 3 hours, and the average diene feed rate was 41 kg / h / mol. Furthermore, for TPE-3, tetrahydrofuran was not added when feeding the conjugated diene compound.

[0161] Examples X7 to X8 Production of Hydrogenated Block Copolymers TPE-7 to TPE-8 Hydrogenated polystyrene-polybutadiene / polyisoprene diblock copolymers (hydrogenated block copolymers TPE-7 to TPE-8) were produced in the same manner as in Example 1, except that the raw materials and their amounts used were as shown in Table 1, the polymerization temperature was 60°C (Example X7) or 50°C (Example X8), and styrene (2) was not added. The average diene feed rates in Examples X7 to X8 were 14 kg / h / mol and 13 kg / h / mol, respectively.

[0162] Comparative Examples 1 to 4 Production of Hydrogenated Block Copolymers TPE-1' to TPE-4' Hydrogenated block copolymers TPE-1' to TPE-4' were produced in the same manner as in Example 1, except that the raw materials and their amounts used were as shown in Table 1, the diene feed time was 2 hours, and the polymerization temperature was 50°C. The average diene feed rates in Comparative Examples 1 to 4 were 24 kg / h / mol, 19 kg / h / mol, 62 kg / h / mol, and 20 kg / h / mol, respectively. In Comparative Examples 1 to 3, tetrahydrofuran was not added when feeding the conjugated diene compound. In Comparative Example 4, only butadiene was used as the conjugated diene compound.

[0163] Comparative Examples X5 to X7 Production of Hydrogenated Block Copolymers TPE-5' to TPE-7' Hydrogenated block copolymers TPE-5' to TPE-7' were produced in the same manner as in Example 1, except that the raw materials and their amounts used were as shown in Table 1, the polymerization temperature was 50°C (Comparative Examples X5 to X6) or 60°C (Comparative Example X7), and styrene (2) was not added. The average diene feed rates in Comparative Examples X5 to X7 were 13 kg / h / mol, 13 kg / h / mol, and 14 kg / h / mol, respectively. In Comparative Examples X5 to X7, tetrahydrofuran was not added when feeding the conjugated diene compound. In Comparative Example X5, only isoprene was used as the conjugated diene compound.

[0164]

[0165] <Physical Properties of Hydrogenated Block Copolymers> The physical properties of hydrogenated block copolymers TPE-1 to TPE-8 and TPE-1' to TPE-7' were measured according to the following measurement methods. The results are shown in Table 2 together with the composition of each hydrogenated block copolymer. Note that "-" in Table 2 indicates that the measurement was not possible because the hydrogenated block copolymer could not be molded. Furthermore, for hydrogenated block copolymer TPE-5' of Comparative Example X5, no crystallization peak could be detected, and therefore the "crystallization temperature" and "crystallization heat" below could not be measured. Therefore, "-" is entered in the corresponding section of Table 2 and in the "5.8x 100000-y" column. ＊ In addition, the polymer block (B) of the hydrogenated block copolymer TPE-5' does not have a structural unit derived from butadiene, and therefore the "1,4Bd sequence ratio" described below cannot be measured. Therefore, the corresponding section in Table 2 is marked with "- ＊＊ "It says:

[0166] (Content of Polymer Block (A) and Polymer Block (B)) The hydrogenated block copolymer was dissolved in CDCl ３ Dissolve in １ H-NMR measurement [apparatus: "AVANCE 400 Nanobay" (manufactured by Bruker), measurement temperature: 30°C] was performed, and the content of polymer block (A) was calculated from the peak intensity attributable to styrene. The content of polymer block (B) was calculated by subtracting the content of polymer block (A) from 100% by mass.

[0167] (Amount of vinyl bond in polymer block (B)) The block copolymer before hydrogenation was ３ Dissolve in １ H-NMR measurement was carried out [apparatus: "AVANCE 400 Nanobay" (manufactured by Bruker), measurement temperature: 30°C]. The amount of vinyl bonds was calculated from the ratio of the peak area corresponding to the 3,4-bond unit and 1,2-bond unit in the isoprene structural unit and the 1,2-bond unit in the butadiene structural unit to the total peak area of ​​structural units derived from butadiene and isoprene.

[0168] (Hydrogenation rate of polymer block (B)) The hydrogenated block copolymer was３ Dissolve in １ H-NMR measurement [apparatus: "AVANCE 400 Nanobay" (manufactured by Bruker), measurement temperature: 30°C] was carried out, and the hydrogenation rate was calculated from the ratio of the peak area of ​​butadiene or isoprene derived from residual olefins to the peak area of ​​hydrogenated butadiene and hydrogenated isoprene.

[0169] (Weight-average molecular weight (Mw)) The weight-average molecular weight (Mw) of the hydrogenated block copolymer, calculated in terms of polystyrene, was determined by gel permeation chromatography (GPC) measurement under the following conditions. Furthermore, the Mw of the polymer block (A) was determined from the peak derived from the deactivated initial polymer block (A) by the same measurement. <<GPC measurement device and measurement conditions>> Device: GPC device "HLC-8020" (manufactured by Tosoh Corporation) Separation column: Two "TSKgel G4000HX" columns manufactured by Tosoh Corporation were connected in series. Eluent: Tetrahydrofuran Eluent flow rate: 0.7 mL / min Sample concentration: 5 mg / 10 mL Column temperature: 40°C Detector: Refractive index (RI) detector Calibration curve: Prepared using standard polystyrene

[0170] (tan δ and shear storage modulus G' at -40°C of hydrogenated block copolymer) For the following measurements, the hydrogenated block copolymers obtained in the examples and comparative examples were pressurized at a temperature of 230°C and a pressure of 10 MPa for 3 minutes to produce a single-layer sheet having a thickness of 1.0 mm. The single-layer sheet was cut into a disk shape to serve as a test sheet. For the measurements, a strain-controlled dynamic viscoelasticity apparatus "ARES-G2" (manufactured by TA Instruments) with a disk diameter of 8 mm was used as a parallel plate oscillatory rheometer in accordance with JIS K7244-10 (2005). The gap between the two flat plates was completely filled with the test sheet, and the sample was subjected to vibration in shear mode at a frequency of 1 Hz with a strain of 1%. The temperature was raised from −80° C. to 0° C. at a constant rate of 3° C. / min, and the maximum value of the peak intensity of tan δ (peak top intensity) of the hydrogenated block copolymer at measurement temperatures from −80 to 0° C., the temperature at which the maximum value was obtained (peak top temperature), and the shear storage modulus G' of the hydrogenated block copolymer at −40° C. were determined.

[0171] (Glass Transition Temperature (Tg)) The Tg of the hydrogenated block copolymer was measured by raising the temperature from −100° C. to +350° C. at a rate of 10° C. / min using a DSC250 manufactured by TA Instruments, and the position of the shift in the baseline of the DSC curve (specifically, the intersection of the line midway between the baselines before and after the onset of a change in specific heat and the DSC curve) was defined as the Tg.

[0172] (Crystallization Temperature and Heat of Crystallization) The crystallization temperature and heat of crystallization of the hydrogenated block copolymer were determined in accordance with JIS K7121 (2012) and JIS K7122 (2012) using a DSC250 manufactured by TA Instruments, with the temperature being changed in the following order: heating step 1, cooling step, and heating step 2. The crystallization temperature was determined from the peak temperature of the DSC curve obtained in the cooling step, and the heat of crystallization was determined from the peak area. The peak area was calculated by using the line passing through the two points on the DSC curve, peak temperature +80°C and peak temperature +50°C, as the baseline. Heating step 1: heating from 40°C to 180°C at a heating rate of 10°C / min. Cooling step: cooling from +180°C to -100°C at a cooling rate of 10°C / min. Heating step 2: heating from -100°C to +180°C at a heating rate of 10°C / min.

[0173] (5.8x / 100,000-y) The value of "5.8x / 100,000-y" was calculated, where x is the weight average molecular weight of the hydrogenated block copolymer measured by the above procedure and y (°C) is the crystallization temperature of the hydrogenated block copolymer.

[0174] (1,4-bond sequence rate of hydrogenated butadiene) The hydrogenated products of the block copolymers obtained in each example and comparative example were subjected to inverse gate decoupling. １３ C-NMR measurement was carried out, and the ratio of the peak appearing at 29.2 ppm among the peaks derived from the 1,4-bonds of the hydrogenated butadiene obtained by the measurement was calculated, and this was taken as the linkage rate of 1,4-bonds of the hydrogenated butadiene (1,4Bd linkage rate).

[0175] (Tensile Strength and Tensile Breaking Elongation) The hydrogenated block copolymers obtained in each Example and Comparative Example were pressed at a temperature of 230°C and a pressure of 10 MPa for 3 minutes to produce a single-layer sheet having a thickness of 1.0 mm. This sheet was punched into the shape of a JIS No. 3 dumbbell-shaped test piece, and the tensile strength and tensile breaking elongation were measured in accordance with JIS K 6251 (2017). Higher values ​​for tensile strength and tensile breaking elongation indicate better tensile properties.

[0176]

[0177] As shown in Table 2, in the hydrogenated block copolymers of Examples 1 to 6 and X7 to X8, the structural units derived from the conjugated diene compound in the polymer block (B) contain structural units derived from butadiene and structural units derived from isoprene, and do not contain structural units derived from farnesene. Furthermore, the glass transition temperature of the hydrogenated block copolymer is −50°C or lower. Furthermore, the weight-average molecular weight x of the hydrogenated block copolymer and the crystallization temperature y (°C) of the hydrogenated block copolymer satisfy the relationship 5.8x / 100,000−y>17. In other words, the hydrogenated block copolymers of Examples 1 to 6 and X7 to X8 satisfy the above-mentioned conditions (1) to (3). Furthermore, it can be seen that the hydrogenated block copolymers of Examples 1 to 6 have low crystallization temperatures and low heats of crystallization, and exhibit good flexibility and rubber elasticity in the low-temperature range. Furthermore, the hydrogenated block copolymers of Examples 1 to 5, which also satisfy the relationships of conditions (I) to (III), generally have low values ​​of shear storage modulus G' at -40°C and 1 Hz, demonstrating excellent rubber elasticity and flexibility in the low temperature range. The hydrogenated block copolymers of Examples X7 and X8 have a diblock polymer structure, and have lower tensile strength and tensile elongation at break than the hydrogenated block copolymers of Examples 1 to 6. However, when compared with Comparative Examples X7 and X6, which have a diblock polymer structure but do not satisfy condition (3), the tensile elongation at break is higher, the tensile strength is equal to or greater, and the shear storage modulus G' at -40°C and 1 Hz is lower.

[0178] On the other hand, the hydrogenated block copolymers of Comparative Examples 1 and 2, which satisfy the above conditions (1) and (2) but not condition (3), and which satisfy the above conditions (I) and (II) but not condition (III), have smaller tensile elongation at break than the hydrogenated block copolymers of Examples 1 to 5. Furthermore, the hydrogenated block copolymer of Comparative Example 1 has a larger shear storage modulus G' at -40°C and 1 Hz than the hydrogenated block copolymers of Examples 1 and 2, which have similar contents of polymer block (A). In other words, it is found that the hydrogenated block copolymers of Comparative Examples 2 and 4 have inferior rubber elasticity and flexibility in the low temperature range compared to the hydrogenated block copolymers of Examples 3 to 5, which have similar contents of polymer block (A). Furthermore, the hydrogenated block copolymers of Comparative Examples 2 and 4 have lower peak-top intensities of tan δ and larger shear storage modulus G' at -40°C and 1 Hz than the hydrogenated block copolymers of Examples 3 to 5, which have similar contents of polymer block (A). In other words, it is found that the rubber elasticity and flexibility are inferior to those of the hydrogenated block copolymers of Examples 3 to 5 in the low temperature range.

[0179] The hydrogenated block copolymer of Example 6, which satisfied the above conditions (1) to (3), (I) and (II), but not (III), and the hydrogenated block copolymer of Comparative Example 3, which satisfied the above conditions (1) and (2) but not (3), and which satisfied the above conditions (I) and (II), but not (III), were poorly moldable and could not be molded. Therefore, it was not possible to measure the tan δ peak-top temperature, tan δ peak-top strength, shear storage modulus G' at -40°C and 1 Hz, tensile strength, and tensile elongation at break. However, as is clear from a comparison of the hydrogenated block copolymer of Example 6 with the hydrogenated block copolymer of Comparative Example 3, the former has a lower crystallization temperature and heat of crystallization than the latter, and exhibits better flexibility and rubber elasticity in the low-temperature range. Furthermore, as shown in Table 3, when these hydrogenated block copolymers were added to an oil component to form a resin composition, the former exhibited higher tensile strength.

[0180] [Example 7] and [Comparative Example 5] Hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples and oils were prepared according to the formulations shown in Table 3. These materials were left at 110°C for 90 minutes, and then kneaded at 110°C and 70 rpm for 5 minutes in a Laboplastomill 10S100 (manufactured by Toyo Seiki Seisakusho Co., Ltd.) to obtain a resin composition. <Oil-1> Diana Process Oil PW-32 (paraffinic oil, manufactured by Idemitsu Kosan Co., Ltd.)

[0181] (Tensile strength) The obtained resin composition was pressed at a temperature of 160 ° C. and a pressure of 2 MPa for 2 minutes to produce a single-layer sheet having a thickness of 2.0 mm. This sheet was punched into the shape of a JIS No. 3 dumbbell-shaped test piece, and the tensile strength was measured according to JIS K 6251 (2017) under the conditions of a chuck distance of 10 mm, a chuck pressure of 0.25 MPa, and a tensile speed of 500 mm / min. The results are shown in Table 3.

[0182] (Oil Retention Rate) The resulting resin composition was pressed at 160°C and 2 MPa for 2 minutes to produce a single-layer sheet with a thickness of 2.0 mm. This sheet was punched out to a diameter of 40 mm, and both sides were sandwiched between filter paper (ADVANTEC No. 5C φ70 mm, manufactured by Advantec Toyo Co., Ltd.), and then sandwiched between glass plates to form a sample. This sample was placed in an environment of 23°C and -30°C, and the filter paper was replaced with new one every 7 days for 28 days. The oil retention rate ((M1 / M0) x 100) was calculated from the weight (M0) of the resin composition sheet before the test and the weight (M1) of the resin composition sheet after 28 days. The results are shown in Table 3.

[0183]

[0184] As shown in Table 3, the resin composition of Example 7 exhibits a higher tensile strength than the resin composition of Comparative Example 5, and also has a higher oil retention rate at 23°C and -30°C than the resin composition of Comparative Example 5. In other words, it can be seen that the resin composition using the hydrogenated block copolymer (TPE-6) that satisfies the above-mentioned conditions (1) to (3) exhibits better mechanical properties and is excellent in oil retention at room temperature and low temperature, compared to the resin composition using the hydrogenated block copolymer (TPE-3') that satisfies the above-mentioned conditions (1) and (2) but does not satisfy condition (3).

[0185] [Examples 8-9] and [Comparative Example 6] Hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples and the following resins were prepared according to the formulations shown in Table 4. These materials were kneaded for 3 minutes at 200°C and 70 rpm in a Laboplastomill 10S100 (manufactured by Toyo Seiki Seisakusho Co., Ltd.) to obtain resin compositions. <PP-1> Prime Polypro J107G (homopolypropylene, manufactured by Prime Polymer Co., Ltd.) <POE-1> ENGAGE 8200 (polyolefin elastomer, manufactured by The Dow Chemical Company) <HDPE-1> SHE150 (high-density polyethylene, manufactured by Braskem)

[0186] (Tensile Properties) Each of the obtained resin compositions was injection molded into an ISO 527-2-1BA dumbbell test piece using a tabletop injection molding machine ("Mini-Jet Pro", manufactured by Thermo Fisher Scientific) to prepare a test piece. After storing the test piece at 23 ° C. for 16 hours, the tensile modulus (23 ° C.), yield stress (23 ° C.), and tensile elongation at break (23 ° C.) were measured using an autograph manufactured by Shimadzu Corporation in accordance with JIS K 7161 (2014). In addition, after storing the test piece at -20 ° C. for 16 hours, the yield stress (-20 ° C.) and tensile elongation at break (-20 ° C.) were measured by performing the same measurements. The results are shown in Table 4.

[0187] (Charpy impact strength) Each of the obtained resin compositions was injection molded into a size of 10 mm long x 80 mm wide x 4 mm thick using a tabletop injection molding machine ("Mini-Jet Pro", manufactured by Thermo Fisher Scientific), and notched according to JIS K 7111-1 (2012) to prepare a test specimen. After storing the test specimen at 23 ° C. for 16 hours, the Charpy impact strength (23 ° C.) was measured using an impact strength measuring instrument. The results are shown in Table 4.

[0188]

[0189] As shown in Table 4, the resin compositions of Examples 8 and 9 exhibit a higher tensile elongation at break (23 ° C) than the resin composition of Comparative Example 6. Furthermore, the resin composition of Example 8 exhibits a higher tensile elongation at break (-20 ° C) than the resin composition of Comparative Example 6. Furthermore, the resin compositions of Examples 8 and 9 exhibit higher impact strength than the resin composition of Comparative Example 6. In other words, it can be seen that resin compositions using hydrogenated block copolymers (TPE-1, TPE-2) satisfying the above-mentioned conditions (1) to (3) and conditions (I) to (III) have improved tensile elongation at break and impact strength compared to resin compositions using hydrogenated block copolymers (TPE-1') that satisfy the above-mentioned conditions (1) and (2) but not condition (3), and that satisfy the above-mentioned conditions (I) and (II) but not condition (III).

[0190] [Examples 10-11] and [Comparative Examples 7-8] According to the formulations shown in Table 5, the hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples and the above HDPE-1 were kneaded in a Laboplastomill 10S100 (manufactured by Toyo Seiki Seisaku-sho, Ltd.) at 200°C and 70 rpm for 3 minutes to obtain resin compositions.

[0191] (Flexural Modulus and Flexural Strength) Each of the obtained resin compositions was injection molded using an injection molding machine ("EC75SX", manufactured by Toshiba Machine Co., Ltd.) to prepare a JIS multipurpose test piece A1. Using the central portion (length 80 mm x width 10 mm x thickness 4 mm) of the test piece, a flexural strength test was performed using a universal testing machine (manufactured by Instron, Model 5566) based on JIS K 7171 (ISO 178), and the flexural modulus [MPa] and flexural strength [MPa] were measured. The results are shown in Table 5.

[0192] (Melt flow rate) For each of the obtained resin compositions, the flow rate (g / 10 min) of the sample was measured using a melt indexer under conditions of a temperature of 23° C. and a load of 2.16 kg in accordance with JIS K 7210: 2014. The results are shown in Table 5.

[0193] (Charpy Impact Strength) The Charpy impact strength (23°C) of each of the obtained resin compositions was measured in the same manner as described above. In addition, the Charpy impact strength (0°C) and the Charpy impact strength (-23°C) were measured in the same manner, but at measurement temperatures of 0°C and -20°C. The results are shown in Table 5.

[0194]

[0195] As shown in Table 5, the resin composition of Example 10 using TPE-7 had values ​​of flexural modulus, flexural strength, and MFR equivalent to or greater than those of the resin composition of Comparative Example 7 using TPE-5', and also had significantly improved Charpy impact strength in the temperature range from near room temperature to low temperatures. Furthermore, the resin composition of Example 11 using TPE-8 also had values ​​of flexural modulus, flexural strength, and MFR equivalent to or greater than those of the resin composition of Comparative Example 8 using TPE-6', and also had improved Charpy impact strength in the temperature range from near room temperature to low temperatures. These results show that resin compositions using hydrogenated block copolymers (TPE-7, TPE-8) that satisfy the above-mentioned conditions (1) to (3) and conditions (I) to (III) have bending properties and fluidity that are equal to or better than resin compositions using hydrogenated block copolymers (TPE-5') that do not satisfy conditions (1), (3), (I), and (III), and resin compositions using hydrogenated block copolymers (TPE-6') that do not satisfy conditions (3) and (III), and that can improve impact resistance over a wide temperature range from near room temperature to low temperatures.

[0196] [Examples 12-13] and [Comparative Examples 9-10] The hydrogenated block copolymers obtained in the above Examples and Comparative Examples and the following oil components were prepared according to the formulations shown in Table 6. The hydrogenated block copolymers and base oils were mixed under nitrogen using a Three-One Motor manufactured by Shinto Chemical Industry Co., Ltd. at 150°C for 3 hours, and then cooled to room temperature to obtain a precursor mixture. The obtained precursor mixture was mixed with lithium grease using a stainless steel spatula at 80-90°C for 30 minutes. The mixture was then cooled to room temperature to obtain a gel composition. <Lithium Grease> - Monotaro Corporation, "Otokomae Monotaro (registered trademark) Lithium Grease" (Consistency number: No. 2, thickener: lithium soap, thickener content: 10% by mass, base oil: mineral oil, base oil content: 85-90% by mass) <Base Oil> - Sanwa Chemical Industry Co., Ltd., "Samic (registered trademark) G-150" (Group II mineral oil)

[0197] (Worked Penetration and Penetration Increase) The penetration (worked penetration) of each obtained gel composition was measured in accordance with item 7 of JIS K 2220:2013. In addition, the mixing stability of each obtained gel composition was measured in accordance with item 15 of JIS K2220:2013, and the difference between the mixing stability and the worked penetration was defined as the penetration increase. The results are shown in Table 6.

[0198] (Oil Separation Rate) The oil separation rate of each gel composition obtained was measured in accordance with JIS K2220:2013, item 11. The results are shown in Table 6.

[0199] (Water resistance after washing) The water resistance after washing of each of the obtained gel compositions was measured in accordance with JIS K2220:2013, item 16. The results are shown in Table 6.

[0200]

[0201] As shown in Table 6, the gel composition of Example 12, which used TPE-8, a hydrogenated block copolymer satisfying conditions (1) to (3), had the same oil separation rate and water-washing resistance as the gel composition of Comparative Example 9, which used TPE-6', a hydrogenated block copolymer that did not satisfy condition (3), but had a lower worked penetration and a relatively low consistency increase, thereby providing properties more suitable for a grease gel composition. Also, as shown in Table 6, the gel composition of Example 13, which used TPE-7, a hydrogenated block copolymer that satisfied conditions (1) to (3), had the same oil separation rate and water-washing resistance as the gel composition of Comparative Example 10, which used TPE-7', a hydrogenated block copolymer that did not satisfy condition (3), but had a lower worked penetration and a relatively low consistency increase, thereby providing properties more suitable for a grease gel composition. These results are presumably due to the improved compatibility between TPE-8, a hydrogenated block copolymer that satisfies conditions (1) to (3), and oil, resulting in an improved thickening effect at temperatures above room temperature.

[0202] [Examples 14-15] and [Comparative Examples 11-12] According to the formulations shown in Table 7, the hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples, and the following components were prepared. These materials were mixed under nitrogen using a Three-One Motor manufactured by Shinto Chemical Co., Ltd. at 150°C for 3 hours. The mixture was then cooled to room temperature to obtain a gel composition. <Base oil> - "SAMIC (registered trademark) G-150" (Group II mineral oil) manufactured by Sanwa Chemical Industry Co., Ltd. <Pour point depressant> - VISCOPLEX 1-330 manufactured by EVONIK

[0203] (Kinematic Viscosity) The kinematic viscosity of each of the obtained gel compositions was measured at 40° C. and 100° C. in accordance with JIS K2283: 2000. The results are shown in Table 7.

[0204] (Viscosity Index) The viscosity index of each gel composition obtained was measured in accordance with JIS K2283: 2000. The results are shown in Table 7.

[0205] (High-temperature, high-shear viscosity at 150° C.) The high-temperature, high-shear viscosity at 150° C. of each of the obtained gel compositions was measured or calculated in accordance with Japan Petroleum Institute's petroleum testing standard JPI-5S-36. The results are shown in Table 7.

[0206] (Kinematic viscosity after shearing) The kinematic viscosity (100°C) of each gel composition obtained was measured by the diesel injector method in accordance with Japan Petroleum Institute's petroleum testing standard JPI-5S-29. The results are shown in Table 7.

[0207] (MRV Viscosity at −30° C.) The low-temperature pumping viscosity at −30° C. (MRV viscosity (−30° C.)) of each of the obtained gel compositions was measured in accordance with ASTM D 4684. The results are shown in Table 7.

[0208]

[0209] As shown in Table 7, the gel composition of Example 14, which used TPE-8, a hydrogenated block copolymer satisfying conditions (1) to (3), had comparable kinematic viscosity, viscosity index, high-temperature high-shear viscosity, and kinematic viscosity after shear at 40 ° C. and 100 ° C., compared to the gel composition of Comparative Example 11, which used TPE-6', a hydrogenated block copolymer that did not satisfy condition (3). However, the MRV viscosity at -30 ° C. was significantly lower. Furthermore, the gel composition of Example 15, which used TPE-7, a hydrogenated block copolymer that satisfied conditions (1) to (3), had comparable kinematic viscosity, viscosity index, high-temperature high-shear viscosity, and kinematic viscosity after shear at 40 ° C. and 100 ° C., compared to the gel composition of Comparative Example 12, which used TPE-7', a hydrogenated block copolymer that did not satisfy condition (3). However, the MRV viscosity at -30 ° C. was significantly lower. Therefore, the gel compositions of Examples 14 and 15 had advantageous properties for engine oil gel compositions with excellent low-temperature properties.

[0210] [Example 16] and [Comparative Example 13] According to the formulations shown in Table 8, the hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples and the following oil components were prepared. These materials were mixed under nitrogen at 150°C for 3 hours using a Three-One Motor manufactured by Shinto Chemical Industry Co., Ltd. The mixture was then cooled to room temperature to obtain a gel composition. <Base oil> - "Samic (registered trademark) G-150" (Group II mineral oil) manufactured by Sanwa Chemical Industry Co., Ltd.

[0211] (Viscosity) The viscosity of each gel composition obtained (25°C, 50 sec) －１ ) was measured at 25°C for 50 seconds using a rheometer (R / S+ RHEOMETER, manufactured by BROOKFIELD). －１ More specifically, about 30 mL of the gel composition was placed in a sample chamber (manufactured by BROOKFIELD, MB3-25F), which was then attached to a rheometer body equipped with a spindle (manufactured by BROOKFIELD, CC3-25). －１ The measurement was then performed for 300 seconds at 1 s and the temperature was stabilized. －１ From the 50s －１ After raising it for 120 seconds, －１ from 1s －１ (2) The shear rate was reduced to 1 s －１ From the 50s －１ After raising it for 120 seconds, －１ from 1s －１ (3) The shear rate was then reduced to 1 s －１ From the 50s －１ After raising it for 120 seconds, －１ from 1s －１ The shear rate in (3) was reduced to 1 s －１ From the 50s －１ The measurement was performed over a 120-second period. －１ The viscosity under the shear rate condition is the viscosity of the gel composition (25°C, 50 sec －１ The results are shown in Table 8.

[0212]

[0213] As shown in Table 8, the gel composition of Example 16, which used TPE-8, a hydrogenated block copolymer satisfying conditions (1) to (3), and the gel composition of Example 17, which used TPE-8, a hydrogenated block copolymer not satisfying condition (3), had higher viscosity at 25°C and had advantageous properties for use as a cable filler, compared to the gel composition of Comparative Example 13, which used TPE-6', a hydrogenated block copolymer not satisfying condition (3). This is presumably because the compatibility of the hydrogenated block copolymer TPE-8, which satisfies conditions (1) to (3), with oil is improved, resulting in an improved thickening effect at temperatures above room temperature.

[0214] [Example 17] and [Comparative Example 14] According to the formulations shown in Table 9, the hydrogenated products of the block copolymers obtained in the above Examples and Comparative Examples, and the following components were prepared. These materials were mixed under nitrogen at 150°C for 3 hours using a Three-One Motor manufactured by Shinto Chemical Co., Ltd. The mixture was then cooled to room temperature to obtain a gel composition. <PAO> - Poly-α-olefin (Durasyn 166 manufactured by INEOS Oligomers)

[0215] (Viscosity) The viscosity of each gel composition obtained (25°C, 50 sec) －１ The results are shown in Table 9.

[0216]

[0217] As shown in Table 9, the gel composition of Example 17, which used TPE-8, a hydrogenated block copolymer that satisfies conditions (1) to (3), had a higher viscosity at 25°C than the gel composition of Comparative Example 14, which used TPE-6', a hydrogenated block copolymer that does not satisfy condition (3), and thus possessed advantageous properties for a cosmetic gel composition. This is presumably due to the improved compatibility of the hydrogenated block copolymer TPE-8, which satisfies conditions (1) to (3), with oil, resulting in an improved thickening effect at temperatures above room temperature.

[0218] The hydrogenated block copolymer and resin composition of the present invention can be used for automobile casings, various automobile-mounted parts and housings, etc. They can also be used in various electrical appliances in the home appliance field, such as televisions, various recorders such as Blu-ray recorders and HDD recorders, projectors, game consoles, digital cameras, home video cameras, antennas, speakers, electronic dictionaries, IC recorders, fax machines, copy machines, telephones, door phones, rice cookers, microwave ovens, oven ranges, refrigerators, dishwashers, dish dryers, induction cooking heaters, hot plates, vacuum cleaners, washing machines, chargers, sewing machines, irons, dryers, electric bicycles, air purifiers, water purifiers, electric toothbrushes, lighting fixtures, air conditioners, outdoor units of air conditioners, dehumidifiers, and humidifiers. The gel composition of the present invention is also useful as a material for cable fillers used in cables such as optical fiber cables, greases, engine oils, cosmetics, lubricating oils, asphalt modifiers, adhesives, pressure-sensitive adhesives, resin modifiers, compatibilizers, sealants, coating materials, molded products, fibers / nonwoven fabrics, drilling fluids, and the like.

Claims

1. A hydrogenated block copolymer comprising a polymer block (A) containing a structural unit derived from an aromatic vinyl compound and a polymer block (B) containing a structural unit derived from a conjugated diene compound, the hydrogenated block copolymer satisfying the following conditions (1) to (3): (1) The structural units derived from a conjugated diene compound in the polymer block (B) contain structural units derived from butadiene and structural units derived from isoprene, but do not contain structural units derived from farnesene. (2) The glass transition temperature of the hydrogenated product of the block copolymer is −50° C. or lower. (3) When the weight average molecular weight of the hydrogenated block copolymer is x and the crystallization temperature of the hydrogenated block copolymer is y (° C.), the relationship 5.8x / 100,000−y>17 is satisfied.

2. The hydrogenated block copolymer according to claim 1, wherein the content of the polymer block (A) in the hydrogenated block copolymer is 5 to 70 mass %.

3. The hydrogenated block copolymer according to claim 2, wherein the content of the polymer block (A) in the hydrogenated block copolymer is 8 to 33 mass %.

4. 2. The hydrogenated block copolymer according to claim 1, wherein the amount of vinyl bonds in the polymer block (B) is 25 mol % or less.

5. 5. The hydrogenated block copolymer according to claim 4, wherein the amount of vinyl bonds in the polymer block (B) is 18 mol % or less.

6. 2. The hydrogenated block copolymer according to claim 1, wherein the content of structural units derived from butadiene in the polymer block (B) is 10 to 90 mol %.

7. 7. The hydrogenated block copolymer according to claim 6, wherein the content of the structural unit derived from butadiene in the polymer block (B) is 15 to 70 mol %.

8. 7. The hydrogenated block copolymer according to claim 6, wherein the content of structural units derived from butadiene in the polymer block (B) is 30 to 85 mol %.

9. 2. The hydrogenated block copolymer according to claim 1, wherein the hydrogenated block copolymer has a heat of crystallization of 20 J / g or less.

10. 2. The hydrogenated block copolymer according to claim 1, wherein the weight average molecular weight of the hydrogenated block copolymer is 30,000 to 500,000.

11. 2. The hydrogenated block copolymer according to claim 1, wherein the hydrogenation rate of the polymer block (B) is 90 mol % or more.

12. The hydrogenated block copolymer according to claim 1 , further satisfying the following condition (4): (4) Inverse gate decoupling １３ The linkage rate of 1,4-bonds of the hydrogenated butadiene, expressed as the ratio of a peak appearing at 29.2 ppm among peaks derived from 1,4-bonds of the hydrogenated butadiene obtained by C-NMR measurement, is less than 50%.

13. The hydrogenated block copolymer according to claim 1, having a tensile elongation at break measured in accordance with JIS K 6251 (2017) of 300% or more.

14. The hydrogenated block copolymer according to claim 1, having a shear storage modulus G' at -40°C of 200 MPa or less, as measured by a complex shear viscosity test at a frequency of 1 Hz in accordance with JIS K7244-10 (2005).

15. As component (a), a hydrogenated product of the block copolymer according to claim 1; A resin composition comprising, as component (b), one or more oil components selected from the group consisting of mineral oils, vegetable oils, and ethylene / α-olefin copolymer oligomers, A resin composition in which the content ratio (a) / (b) of component (a) to component (b) is 1 / 99 to 99 / 1 in terms of mass ratio.

16. As component (a), a hydrogenated product of the block copolymer according to claim 1; A resin composition comprising, as component (c), one or more selected from the group consisting of polyethylene, polypropylene, a styrene-based resin, polyphenylene ether, a polyester resin, polycarbonate, polyacetal, polyamide, polyarylene sulfide, polyarylate, polyimide, polyether ether ketone, and a liquid crystal polyester, A resin composition in which the content ratio (a) / (c) of component (a) to component (c) is 1 / 99 to 99 / 1 in terms of mass ratio.

17. A gel composition comprising as a component (α) the hydrogenated product of the block copolymer according to claim 1 and as a base oil (β).

18. A cable filler comprising the gel composition of claim 17.

19. A cable comprising the gel composition of claim 17.

20. A cosmetic product comprising the gel composition of claim 17.

21. A lubricating oil comprising the gel composition of claim 17.

22. A grease comprising the gel composition of claim 17.

23. A method for producing a hydrogenated product of the block copolymer according to any one of claims 1 to 14, comprising the steps of: a first step of performing a polymerization reaction using at least an aromatic vinyl compound, butadiene, and isoprene as monomers in the presence of a polymerization initiator to obtain a block copolymer comprising a polymer block (A) containing a structural unit derived from the aromatic vinyl compound and a polymer block (B) containing a structural unit derived from the butadiene and a structural unit derived from the isoprene; and a second step of hydrogenating the block copolymer; The method for producing a hydrogenated block copolymer, comprising carrying out at least one of the following steps (i) to (vi): (i) The average feed rate when the butadiene and isoprene are fed to the reaction system is set to 50 kg / h / mol or less. (ii) The polymerization temperature is set to 55 to 80°C. (iii) Adding 0.3% by mass or less of a vinylating agent to the reaction system based on the total mass of the raw material compounds. (iv) The time for feeding the butadiene and isoprene to the reaction system is 2.5 hours or longer. (v) When the amount of the polymerization initiator added is P (mol) and the amount of the unreacted conjugated diene monomer is Q (mol), Q / P during polymerization of the polymer block (B) is 100 or less. (vi) The mass ratio of butadiene and isoprene when being fed to the reaction system is varied depending on the time of feeding them to the reaction system.