JP4425602B2 - Hydrogenated block copolymer or film - Google Patents

Description

The present invention relates to a hydrogenated block copolymer and a composition thereof excellent in balance of physical properties such as solvent resistance, natural shrinkage, low temperature shrinkage, rigidity, transparency and impact resistance suitable for heat shrinkable films. .
In addition, the present invention is excellent in the balance of physical properties such as solvent resistance, natural shrinkage, low temperature shrinkage, rigidity, blocking resistance, hot water fusion resistance and impact resistance, and has few fish eyes (FE) due to gel. The present invention relates to a sheet film, a heat-shrinkable film, and a heat-shrinkable multilayer film.

  A block copolymer composed of a vinyl aromatic hydrocarbon and a conjugated diene, which has a relatively high vinyl aromatic hydrocarbon content, is used for injection molding applications, sheets, films, etc. by utilizing characteristics such as transparency and impact resistance. It is used for extrusion molding applications. In particular, heat-shrinkable films using block copolymer resins composed of vinyl aromatic hydrocarbons and conjugated dienes are the residual monomers and plasticizers of vinyl chloride resins used in the past, and the generation of hydrogen chloride during incineration. Since there is no problem, it is used for food packaging, cap seals, labels, etc. Properties required for heat-shrinkable films include natural shrinkage, low-temperature shrinkage, transparency, mechanical strength, suitability for packaging machines, and the like. So far, various studies have been made to improve these characteristics and obtain a good balance of physical properties.

For example, the following document 1 discloses a method for producing a heat-shrinkable film in order to improve heat shrinkability, after preheating the styrene-butadiene block copolymer within the melting point range and then stretching. The following document 2 discloses a styrene-based resin shrink film in which a specific orientation relaxation stress is maintained in a biaxially stretched film of a styrene / butadiene block copolymer in order to improve shrinkage characteristics.
In the following document 3, in order to obtain a composition having excellent mechanical properties, optical properties, stretching properties, crack resistance properties, etc., the content of the aliphatic unsaturated carboxylic acid derivative is 5 to 80% by weight, and the Vicat softening point is 90 ° C. A composition comprising a vinyl aromatic hydrocarbon-aliphatic unsaturated carboxylic acid derivative copolymer and a copolymer comprising a block of vinyl aromatic hydrocarbon and a conjugated diene, which does not exceed 1 is disclosed.

Reference 4 below discloses a heat-shrinkable film having a specific Tg in a block copolymer segment composed of a vinyl aromatic hydrocarbon and a conjugated diene in order to obtain a heat-shrinkable film having excellent shrinkage characteristics and environmental destruction resistance. It is disclosed. Reference 5 below discloses a heat-shrinkable film comprising a composition of a block copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene having a specific structure in order to obtain a heat-shrinkable film having excellent shrinkage properties and environmental destruction resistance. It is disclosed.
In the following document 6, in order to obtain a shrink film excellent in low-temperature shrinkage, optical properties, crack resistance properties, dimensional stability, etc., the vinyl aromatic hydrocarbon content is 95 to 20% by weight, and the Vicat softening point is 90 ° C. Disclosed is a low-temperature shrinkable film obtained by stretching a composition of a vinyl aromatic hydrocarbon-aliphatic unsaturated carboxylic acid derivative copolymer and a copolymer comprising vinyl aromatic hydrocarbon and a conjugated diene block. Yes.

In the following document 7, in order to improve the natural shrinkability at room temperature, a composition of a block copolymer comprising a styrene hydrocarbon and a conjugated diene hydrocarbon and a random copolymer having a specific Tg containing a styrene hydrocarbon is disclosed. A polystyrene-based heat-shrinkable film is disclosed. Reference 8 below discloses a vinyl aromatic hydrocarbon-aliphatic unsaturated carboxylic acid derivative whose Vicat softening point does not exceed 105 ° C. in order to obtain a transparent heat-shrinkable film having excellent temporal stability and impact resistance of the film. A heat-shrinkable hard film characterized by a specific heat-shrinking force is disclosed in a composition of a copolymer and a copolymer comprising a block of vinyl aromatic hydrocarbon and conjugated diene.
Reference 9 below provides a copolymer comprising vinyl aromatic hydrocarbon and conjugated diene blocks having a specific structure and molecular weight distribution, and a vinyl aromatic in order to obtain a composition that balances transparency, rigidity, and low-temperature impact. Compositions with hydrocarbon- (meth) acrylic ester copolymer resins are disclosed. To obtain a resin composition excellent in transparency and impact resistance in the following Document 10, a block copolymer having a vinyl aromatic hydrocarbon block vinyl aromatic hydrocarbon and a conjugated diene copolymer block having a specific structure; A transparent high-strength resin composition containing a copolymer of vinyl aromatic hydrocarbon and (meth) acrylic acid ester is disclosed.

In Patent Document 11 below, in order to obtain a shrink film excellent in low-temperature shrinkage, optical properties, crack resistance properties, dimensional stability, etc., the vinyl aromatic hydrocarbon content is 95 to 20% by weight, and the Vicat softening point is 90. Multilayer low temperature shrinkage having at least one composition of vinyl aromatic hydrocarbon-aliphatic unsaturated carboxylic acid derivative copolymer not exceeding ℃ and copolymer comprising vinyl aromatic hydrocarbon and conjugated diene block A film is disclosed.
In Patent Document 12 below, in order to obtain a shrink film excellent in natural shrinkage, strength, surface characteristics, waist strength, low temperature shrinkage, etc., both outer layers have a specific butadiene unit content in styrene-butadiene-styrene type block copolymer. Disclosed is a multilayer polystyrene-based heat-shrinkable film having at least three layers comprising a mixture of a polymer and a styrene-butyl acrylate, and an intermediate layer comprising a mixture of a styrene-butadiene-styrene block copolymer having a specific butadiene unit content and a styrene-butyl acrylate. Yes.

In Patent Document 13 below, in order to obtain a heat-shrinkable film excellent in any of the properties of natural shrinkage, heat-resistant fusion, transparency, and shrinkage finish, a vinyl aromatic hydrocarbon and a conjugated diene hydrocarbon are used. A block copolymer consisting of a vinyl aromatic hydrocarbon and a conjugated diene hydrocarbon, with a blend comprising a block copolymer, a copolymer of vinyl aromatic hydrocarbon and an aliphatic unsaturated carboxylic acid ester as an intermediate layer A heat-shrinkable polystyrene-based laminated film is disclosed in which a mixed polymer containing a coalescence as a main component is used as front and back layers.
Patent Document 14 listed below discloses a styrene having a specific Vicat softening point in order to obtain a heat-shrinkable film having no heat-shrinkability at low temperatures, shrinkage finish, natural shrinkage, heat, and no blocking between films. -A multilayer heat-shrinkable polystyrene system having a specific heat shrinkage ratio mainly composed of a (meth) acrylic acid ester copolymer and the inner and outer layers of a styrene-conjugated diene block copolymer having a specific Vicat softening point. A film is disclosed.

The following Patent Document 15 is characterized by a specific molecular weight distribution and a residual monomer amount in order to obtain a resin composition and film having a low processing property, storage stability, odor, and excellent rigidity and impact resistance, and a multilayer film. A copolymer resin composed of a styrene monomer and a (meth) acrylic acid ester monomer, a block copolymer resin composed of styrene and a conjugated diene, and a layer mainly composed of a high-impact polystyrene resin composition A (multilayer) heat shrinkable film is disclosed.
However, the composition of these block copolymer of vinyl aromatic hydrocarbon and conjugated diene or the block copolymer and vinyl aromatic hydrocarbon-aliphatic unsaturated carboxylic acid derivative copolymer is solvent resistant. , Natural shrinkage, low temperature shrinkage, rigidity, transparency, blocking resistance, hot water fusion resistance and impact resistance balance and gel-induced fisheye (FE) are not enough, There is no disclosure on how to improve the system, and problems in the market are still pointed out.

JP 57-34921 A JP 58-108112 A JP 59-221348 A JP-A-60-224520 JP 60-224522 A JP-A-61-25819 JP-A-4-52129 JP-A-5-104630 JP-A-6-220278 JP 7-216187 A JP 61-41544 A JP 2000-185373 A JP 2000-6329 A JP 2002-46231 A JP 2002-201324 A

  The present invention relates to a hydrogenated block copolymer and a composition thereof suitable for a heat-shrinkable film having an excellent balance of physical properties such as solvent resistance, natural shrinkage, low-temperature shrinkage, rigidity, transparency and impact resistance. For the purpose of provision.

As a result of intensive studies, the present inventors have found that the above object can be achieved by a specific block copolymer hydrogenated product, and have reached the present invention. That is, the present invention
[1] Hydrogenated block copolymer having a weight ratio of vinyl aromatic hydrocarbon to conjugated diene of 60/40 to 95/5 and a number average molecular weight of 3 to 500,000 as measured by gel permeation chromatography (GPC) The block ratio of the vinyl aromatic hydrocarbon incorporated in the hydrogenated product is 10 to 98% by weight, and the vinyl aromatic hydrocarbon polymer block in the hydrogenated product has a molecular weight of 35,000 or less. A hydrogenated block copolymer in which the proportion of a certain vinyl aromatic hydrocarbon polymer block is less than 40% by weight of the total vinyl aromatic hydrocarbon polymer block;

[2] The block copolymer as described in [1] above, wherein at least one vinyl aromatic hydrocarbon polymer block having a peak molecular weight in the molecular weight range of 35,000 to 150,000 is incorporated in the hydrogenated block copolymer. Combined hydrogenated product,
[3] The component (A) which is a hydrogenated block copolymer according to any one of [1] or [2] and a component (B) which is a vinyl aromatic hydrocarbon polymer, A composition in which the weight ratio of (A) to component (B) is 99.9 / 0.1 to 20/80;
[4] A hydrogenated block copolymer according to any one of [1] or [2], or a sheet / film comprising the composition according to [3],

[5] A hydrogenated block copolymer according to any one of [1] or [2] or a composition according to [3], which is stretched and has a heat shrinkage of 80 ° C. in the stretching direction. Is a heat-shrinkable film having a tensile elastic modulus in the stretching direction of 7000-30000 Kg / cm ² ,
[6] The block copolymer hydrogenated product according to any one of [1] or [2] above or the layer comprising the composition according to [3] above is used as at least one layer of a multilayer film, and stretched It is related with the heat-shrinkable multilayer film characterized by the heat shrinkage rate of 80 degreeC in a direction being 5 to 60%.

  The heat shrinkable film using the hydrogenated block copolymer of the present invention is excellent in the balance of physical properties such as solvent resistance, natural shrinkage, low temperature shrinkage, rigidity, transparency and impact resistance.

Hereinafter, the present invention will be described in detail. The hydrogenated block copolymer of the present invention has a weight ratio of vinyl aromatic hydrocarbon to conjugated diene of 60/40 to 95/5, preferably 65/35 to 90/10, more preferably 70/30 to 85/15. When the ratio of the vinyl aromatic hydrocarbon to the conjugated diene is 60/40 or more, a heat-shrinkable film having excellent rigidity can be obtained, and when it is 95/5 or less, a heat-shrinkable film having improved impact resistance can be obtained. The vinyl aromatic hydrocarbon content of the block copolymer hydrogenated product may be grasped by the vinyl aromatic compound content of the block copolymer before hydrogenation.
The block ratio of the vinyl aromatic hydrocarbon incorporated in the hydrogenated block copolymer of the present invention is 10 to 98% by weight, preferably 15 to 95% by weight, and more preferably 25 to 90% by weight. When the block ratio is 10% by weight or more, it is possible to obtain a heat-shrinkable film having excellent hot water fusion property and 85% by weight or less having excellent low-temperature shrinkage. In the case of obtaining a hydrogenated block copolymer with good rigidity, the block ratio of the vinyl aromatic hydrocarbon exceeds 50% by weight and is 98% by weight or less, preferably 60 to 95% by weight, more preferably 65 to 65% by weight. 90% by weight is recommended.

The block ratio of the vinyl aromatic hydrocarbon incorporated in the hydrogenated block copolymer of the present invention is determined by oxidative decomposition of the block copolymer before hydrogenation with tertiary butyl hydroperoxide using osmium tetroxide as a catalyst. Vinyl aromatic hydrocarbon polymer block component (however, average polymerization) obtained by the method (method described in IM KOLTHOFF, et al., J. Polym. Sci. 1, 429 (1946)). The vinyl aromatic hydrocarbon polymer component having a degree of about 30 or less is excluded, and the value obtained from the following equation is used.
Block ratio (% by weight) = (weight of vinyl aromatic hydrocarbon polymer block in block copolymer / weight of total vinyl aromatic hydrocarbon in block copolymer) × 100
The block copolymer hydrogenated product of the present invention is a vinyl aromatic hydrocarbon polymer having a molecular weight of 35,000 to 150,000, preferably 35,000 to 130,000, more preferably 35,000 to 100,000, and particularly preferably 40000 to 80,000. At least one block is incorporated into the block copolymer hydrogenation.

In the block copolymer hydrogenated product of the present invention, by incorporating at least one vinyl aromatic hydrocarbon polymer block having a peak molecular weight in the range of molecular weight 35,000 to 150,000, solvent resistance, natural shrinkage, A heat-shrinkable film excellent in low-temperature shrinkage and hot water resistance can be obtained.
The block copolymer hydrogenated product of the present invention is a ratio of the vinyl aromatic hydrocarbon polymer block having a molecular weight of 35,000 or less in the vinyl aromatic hydrocarbon polymer block incorporated in the block copolymer hydrogenated product. Is less than 40% by weight of the total vinyl aromatic hydrocarbon polymer block, preferably 5 to 35% by weight, more preferably 8 to 30% by weight, and particularly preferably 12 to 25% by weight. When the proportion of the vinyl aromatic hydrocarbon polymer block having a molecular weight of 35000 or less is less than 40% by weight of the total vinyl aromatic hydrocarbon polymer block, the heat shrinkage is excellent in solvent resistance, natural shrinkage and low temperature shrinkage. Can be obtained.

  In the present invention, the molecular weight of the vinyl aromatic hydrocarbon polymer block incorporated in the block copolymer hydrogenated product is the same as the vinyl aromatic used for quantification of the block ratio obtained by the oxidative decomposition method described above. The molecular weight of a hydrocarbon polymer block component is specified by gel permeation chromatography (GPC). The molecular weight of monodisperse polystyrene for gel permeation chromatography (GPC) is prepared by GPC and a calibration curve is created between the peak count and the number average molecular weight of the monodisperse polystyrene. > "Kodansha"). The peak molecular weight can be determined from the gel permeation chromatogram, and the proportion of the vinyl aromatic hydrocarbon polymer block component having a molecular weight of 35,000 or less can be determined from the area ratio of the gel permeation chromatogram. The molecular weight of the vinyl aromatic hydrocarbon block incorporated in the block copolymer hydrogenated product and the molecular weight of 35,000 or less are the weight of the vinyl aromatic hydrocarbon, the weight and weight ratio of the vinyl aromatic hydrocarbon and the conjugated diene, It can be controlled by changing the polymerization reactivity ratio, the amount of catalyst, and the like.

  The block copolymer hydrogenated product of the present invention has a number average molecular weight (polystyrene equivalent molecular weight) of 30,000 to 500,000, preferably 50,000 to 500,000, more preferably 70,000 as measured by gel permeation chromatography (GPC). It may be a range of ˜300,000 and may be a mixture of a plurality of block copolymers having different molecular weights. The preferred melt flow rate of the block copolymer (measured according to JISK-6870. Conditions are G condition, temperature 200 ° C., load 5 Kg) from the viewpoint of molding processability, 0.1-100 g / 10 min, 0.5-50 g / It is recommended that it be 10 min, more preferably 1-30 g / 10 min. The molecular weight and melt flow rate (hereinafter sometimes abbreviated as MFR) can be arbitrarily adjusted depending on the amount of catalyst used for the polymerization.

The content of the short-chain vinyl aromatic hydrocarbon polymerized moiety in which the number of vinyl aromatic hydrocarbon units is in the range of 1 to 3 with respect to the total amount of vinyl aromatic hydrocarbon constituting the hydrogenated block copolymer of the present invention is 1 to It is recommended that it be 25% by weight, preferably 3-23% by weight, more preferably 5-20% by weight. When the content of the short chain vinyl hydrocarbon polymerized moiety is in the range of 1 to 25% by weight, the rigidity is high and the natural shrinkage is good. The content of the short-chain vinyl aromatic hydrocarbon is determined by dissolving the block copolymer before hydrogenation in dichloromethane and oxidatively decomposing it with ozone (O ₃ ), and then converting the obtained ozonide to aluminum hydride in diethyl ether. Quantification is performed by performing gel permeation chromatography (GPC) measurement of vinyl aromatic hydrocarbon components obtained by reduction with lithium and hydrolysis with pure water, and calculating the area ratio of the obtained peaks. Yes (see Takayuki Tanaka, Toshiya Sato, Yasunobu Nakafumi, “Proceedings of the Society of Polymer Science” 29, 2051, 1980).

  The content of the short-chain vinyl aromatic hydrocarbon moiety is the weight of the vinyl aromatic hydrocarbon and the conjugated diene in the process of copolymerizing the vinyl aromatic hydrocarbon and the conjugated diene during the production of the block copolymer hydrogenated product, It can be controlled by changing the weight ratio, the polymerization reactivity ratio, and the like. As a specific method, a mixture of a vinyl aromatic hydrocarbon and a conjugated diene is continuously supplied to a polymerization system for polymerization, and / or a vinyl aromatic hydrocarbon and a polar compound or a randomizing agent are used. A method such as copolymerization of a conjugated diene can be employed. Examples of polar compounds and randomizing agents include ethers such as tetrahydrofuran, diethylene glycol dimethyl ether and diethylene glycol dibutyl ether, amines such as triethylamine and tetramethylethylenediamine, thioethers, phosphines, phosphoramides, alkylbenzene sulfonates, potassium and sodium. An alkoxide etc. are mentioned. The microstructure of the conjugated diene monomer unit in the block copolymer described later can be adjusted by adding a predetermined amount of a polar compound or the like.

The block copolymer hydrogenated product of the present invention comprises at least one segment composed of a vinyl aromatic hydrocarbon homopolymer and / or a copolymer composed of a vinyl aromatic hydrocarbon and a conjugated diene, and a conjugated diene homopolymer. It has at least one segment composed of a copolymer and / or a copolymer comprising a vinyl aromatic hydrocarbon and a conjugated diene. The polymer structure before hydrogenation of the block copolymer hydrogenated product is not particularly limited.
(AB) _n , A- (BA) _n , B- (AB) _{n + 1}
[(A−B) _k ] _{m + 1} −X, [(A−B) _k −A] _{m + 1} −X
[(BA) k] _{m + 1-} X, [(BA) _k- B] _{m + 1-} X

(In the above formula, segment A is a vinyl aromatic hydrocarbon homopolymer and / or a copolymer comprising vinyl aromatic hydrocarbon and conjugated diene, and segment B is a conjugated diene homopolymer and / or vinyl aromatic hydrocarbon. X is a copolymer of a conjugated diene, for example, X is a residue or polyvalent of a coupling agent such as silicon tetrachloride, tin tetrachloride, 1,3 bis (N, N-glycidylaminomethyl) cyclohexane, epoxidized soybean oil, etc. It represents a residue of an initiator such as a functional organolithium compound, where n, k, and m are integers of 1 or more, generally an integer of 1 to 5. In addition, the structure of a polymer chain that is bonded to X by a plurality May be the same or different.) A linear block copolymer hydrogenated product, a radial block copolymer hydrogenated product represented by the following formula, or any mixture of these polymer structures may be used.Further, in the hydrogenated radial block copolymer represented by the above general formula, at least one A and / or B may be bonded to X.

  In the present invention, the vinyl aromatic hydrocarbon in the copolymer of vinyl aromatic hydrocarbon and conjugated diene in segment A and segment B may be distributed uniformly or in a tapered (gradual decrease) form. Good. In the hydrogenated product of the copolymer, a plurality of portions where vinyl aromatic hydrocarbons are uniformly distributed and / or portions where tapes are distributed may coexist in the segment. Vinyl aromatic hydrocarbon content in segment A ({vinyl aromatic hydrocarbon in segment A / (vinyl aromatic hydrocarbon in segment A + conjugated diene)} × 100) and vinyl aromatic carbon in segment B The relationship between the hydrogen content ({vinyl aromatic hydrocarbon in segment B / (vinyl aromatic hydrocarbon in segment B + conjugated diene)} × 100) is greater with the vinyl aromatic hydrocarbon content in segment A. , Greater than the vinyl aromatic hydrocarbon content in segment B. The difference in the preferred vinyl aromatic hydrocarbon content between segment A and segment B is preferably 5% by weight or more.

  In the present invention, the block copolymer before hydrogenation can be obtained by polymerizing vinyl aromatic hydrocarbon and conjugated diene in a hydrocarbon solvent using an organolithium compound as an initiator. Examples of the vinyl aromatic hydrocarbon used in the present invention include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene, 1, Examples include 1-diphenylethylene, N, N-dimethyl-p-aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene, and a particularly common one is styrene. These may be used alone or in combination of two or more.

The conjugated diene is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene. 1,3-pentadiene, 1,3-hexadiene, etc., and particularly common examples include 1,3-butadiene and isoprene. These may be used alone or in combination of two or more.
In the block copolymer hydrogenated product of the present invention, (i) a copolymer block comprising isoprene and 1,3-butadiene, (ii) a copolymer block comprising isoprene and a vinyl aromatic hydrocarbon, and (iii) isoprene. And at least one polymer block selected from the group (i) to (iii) of a copolymer block comprising 1,3-butadiene and vinyl aromatic hydrocarbon is incorporated, and the weight ratio of butadiene to isoprene is The block copolymer hydrogenated product having a ratio of 3/97 to 90/10, preferably 5/95 to 85/15, more preferably 10/90 to 80/20 has a hydrogenation rate of 50% by weight or less. Produces less gel in thermoforming and processing.

In the present invention, the block copolymer before hydrogenation is obtained, for example, by anion living polymerization using an initiator such as an organic alkali metal compound in a hydrocarbon solvent. Examples of the hydrocarbon solvent include aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, and cycloheptane. In addition, alicyclic hydrocarbons such as methylcycloheptane, and aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene can be used. These may be used alone or in combination of two or more.
As the polymerization initiator, aliphatic hydrocarbon alkali metal compounds, aromatic hydrocarbon alkali metal compounds, organic amino alkali metal, which are generally known to have anionic polymerization activity for conjugated dienes and vinyl aromatic compounds. A compound or the like can be used. Examples of the alkali metal include lithium, sodium, potassium, and the like. Suitable organic alkali metal compounds are aliphatic and aromatic hydrocarbon lithium compounds having 1 to 20 carbon atoms, and one lithium per molecule. And dilithium compounds, trilithium compounds, and tetralithium compounds containing a plurality of lithium atoms in one molecule.

  Specifically, n-propyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, hexamethylene dilithium, butadienyl dilithium, isoprenyl dilithium, diisopropenylbenzene and sec-butyl lithium Examples of the reaction product include a reaction product of divinylbenzene, sec-butyllithium and a small amount of 1,3-butadiene. Furthermore, organic alkali metal compounds disclosed in US Pat. No. 5,708,092, British Patent 2,241,239, US Pat. No. 5,527,753, etc. are also used. be able to. These may be used alone or in combination of two or more.

  In the present invention, the polymerization temperature for producing the block copolymer before hydrogenation is generally -10 ° C to 150 ° C, preferably 40 ° C to 120 ° C. The time required for the polymerization varies depending on the conditions, but is usually within 10 hours, particularly preferably 0.5 to 5 hours. The polymerization atmosphere is preferably replaced with an inert gas such as nitrogen gas. The polymerization pressure is not particularly limited as long as it is carried out within a range of pressure sufficient to maintain the monomer and solvent in the liquid layer within the above polymerization temperature range. Furthermore, care must be taken not to mix impurities, such as water, oxygen, carbon dioxide, etc., that inactivate the catalyst and living polymer into the polymerization system.

  The hydrogenated block copolymer of the present invention can be obtained by hydrogenating the block copolymer before hydrogenation obtained above. The hydrogenation catalyst is not particularly limited and is conventionally known (1) A supported heterogeneous hydrogenation in which a metal such as Ni, Pt, Pd, or Ru is supported on carbon, silica, alumina, diatomaceous earth, or the like. A catalyst, (2) a so-called Ziegler-type hydrogenation catalyst using an organic acid salt such as Ni, Co, Fe, Cr or a transition metal salt such as acetylacetone salt and a reducing agent such as organic aluminum, (3) Ti, Ru, A homogeneous hydrogenation catalyst such as a so-called organometallic complex such as an organometallic compound such as Rh or Zr is used. Specific examples of the hydrogenation catalyst include Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication No. 1-337970, Japanese Patent Publication No. 1-53851, The hydrogenation catalyst described in Japanese Utility Model Publication No. 2-9041 can be used. A preferred hydrogenation catalyst is a mixture with a titanocene compound and / or a reducing organometallic compound.

As the titanocene compound, compounds described in JP-A-8-109219 can be used. Specific examples thereof include (substitution) such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. Examples thereof include compounds having at least one ligand having a cyclopentadienyl skeleton, an indenyl skeleton, or a fluorenyl skeleton. Examples of the reducing organometallic compound include organic alkali metal compounds such as organolithium, organomagnesium compounds, organoaluminum compounds, organoboron compounds, and organozinc compounds.
The hydrogenation reaction is generally carried out in a temperature range of 0 to 200 ° C, more preferably 30 to 150 ° C. The pressure of hydrogen used for the hydrogenation reaction is 0.1 to 15 MPa, preferably 0.2 to 10 MPa, and more preferably 0.3 to 7 MPa. The hydrogenation reaction time is usually 3 minutes to 10 hours, preferably 10 minutes to 5 hours. The hydrogenation reaction can be any of a batch process, a continuous process, or a combination thereof.

  In the hydrogenated block copolymer of the present invention, the hydrogenation rate of the unsaturated double bond based on the conjugated diene can be arbitrarily selected according to the purpose and is not particularly limited. When obtaining a hydrogenated block copolymer having good thermal stability and weather resistance, it exceeds 70%, preferably 75% or more, more preferably 85% of the unsaturated double bond based on the conjugated diene compound in the polymer. % Or more, particularly preferably 90% or more is recommended to be hydrogenated. Further, when obtaining a hydrogenated block copolymer having good thermal stability, the hydrogenation rate is preferably 3 to 70%, alternatively 5 to 65%, particularly preferably 10 to 60%. The hydrogenation rate of the aromatic double bond based on the vinyl aromatic hydrocarbon in the copolymer is not particularly limited, but the hydrogenation rate is 50% or less, preferably 30% or less, more preferably 20%. The following is preferable. The hydrogenation addition rate can be known by a nuclear magnetic resonance apparatus (NMR).

  In the present invention, the microstructure (cis, trans, vinyl ratio) of the conjugated diene moiety in the hydrogenated block copolymer can be arbitrarily changed by the use of the above-mentioned polar compound and the like, and is not particularly limited. In general, the vinyl bond amount can be set in the range of 5 to 90%, preferably 10 to 80%, more preferably 15 to 75%. In the present invention, the amount of vinyl bonds means the total amount of 1,2-vinyl bonds and 3,4-vinyl bonds (however, when 1,3-butadiene is used as the conjugated diene, 1,2-vinyl bonds are used. Binding amount). The amount of vinyl bonds can be grasped by a nuclear magnetic resonance apparatus (NMR).

  In the present invention, when obtaining a block copolymer hydrogenated product having particularly excellent hot water fusion property, a differential scanning calorimetry (DSC) chart of the block copolymer hydrogenated product is 20 ° C. or higher, preferably 30 ° C. As described above, a hydrogenated block copolymer having a crystallization peak in a temperature range of 45 to 100 ° C., particularly preferably 50 to 90 ° C. is preferable. The crystallization peak heat quantity is 3 J / g or more, preferably 6 J / g or more, more preferably 10 J / g or more. The hydrogenated block copolymer having a crystallization peak has a vinyl bond content in the block copolymer before hydrogenation of less than 30%, preferably 8 to 25%, more preferably 10 to 25%, particularly preferably. It can be obtained by setting to 12 to 20%. In particular, it is recommended that the block copolymer before hydrogenation contains at least one conjugated diene polymer segment having a vinyl bond content of 8 to 25%, preferably 10 to 20%, more preferably 10 to 18%. Is done.

  In the hydrogenated block copolymer of the present invention, the preferred range of the function tan δ in the dynamic viscoelasticity measurement is 70 to 120 ° C, more preferably 75 to 115 ° C, and particularly preferably 80 to 110 ° C. The function tan δ in the dynamic viscoelasticity measurement is a value measured by, for example, a rheological viscoelasticity measurement / analysis apparatus DVE-V4 manufactured by Rheology Co., Ltd. or Leo Vibron DDV-3 manufactured by Toyo Baldwin, Inc., and has a vibration frequency of 35 Hz and a heating rate. Measurement is performed using a test piece having a thickness of 0.5 to 2 mm under the condition of 3 ° C./min. The temperature showing the peak means a temperature at which the first derivative of the amount of change of the tan δ value with respect to the temperature becomes zero. The tan δ peak temperature is the weight ratio of vinyl aromatic hydrocarbon and conjugated diene, the molecular weight of the block copolymer hydrogenated product, the content of the vinyl aromatic hydrocarbon polymer block in the block copolymer hydrogenated product, the block It is adjusted depending on the content of the short chain vinyl aromatic hydrocarbon polymerized portion in which the number of vinyl aromatic hydrocarbon units in the hydrogenated copolymer is in the range of 1 to 3.

  The block copolymer hydrogenated product of the present invention (hereinafter also referred to as component (A)) is a block copolymer with a vinyl aromatic hydrocarbon polymer (hereinafter also referred to as component (B)). It can be used as a polymer composition. The weight ratio of component (A) to component (B) is 99.9 / 0.1 to 20/80, preferably 99.7 / 0.3 to 25/75, more preferably 99/1 to 30/70. It is. By combining the component (A) and the component (B) at such a weight ratio, a block copolymer composition excellent in rigidity, blocking resistance and natural shrinkage can be obtained.

In the present invention, as the vinyl aromatic hydrocarbon polymer, at least one selected from the following a) to c) can be used.
a) Styrenic polymer b) At least one aliphatic unsaturated carboxylic acid selected from vinyl aromatic hydrocarbons and aliphatic unsaturated carboxylic acids, aliphatic unsaturated carboxylic acid anhydrides and aliphatic unsaturated carboxylic acid esters Copolymer with acid or derivative thereof c) Rubber-modified styrene polymer

  The a) styrenic polymer used in the present invention is one obtained by polymerizing styrene or a monomer copolymerizable therewith (except for b). Examples of the monomer copolymerizable with styrene include α-methylstyrene, acrylonitrile, maleic anhydride and the like. Examples of the styrenic polymer include polystyrene, styrene-α-methylstyrene copolymer, acrylonitrile-styrene copolymer, and styrene-maleic anhydride copolymer. Particularly preferable styrene polymer is polystyrene. I can give you. A polymer having a weight average molecular weight of 50,000 to 500,000 can be generally used. These styrenic polymers can be used singly or as a mixture of two or more, and can be used as a rigidity improving agent.

  B) vinyl aromatic hydrocarbon and aliphatic unsaturated carboxylic acid, aliphatic unsaturated carboxylic acid anhydride, aliphatic unsaturated carboxylic acid ester selected from b) used in the present invention Examples of the aliphatic unsaturated carboxylic acid used in the copolymer with the acid or its derivative include acrylic acid, methacrylic acid, fumaric acid, itaconic acid, maleic acid, and the like, and aliphatic unsaturated carboxylic acid anhydrides. Examples thereof include fumaric anhydride, itaconic anhydride, maleic anhydride, and the like, and as the aliphatic unsaturated carboxylic acid ester, the above aliphatic unsaturated carboxylic acid and C1-C12, preferably C2-C12. Mono or diester with alcohol is mentioned. The content of the aliphatic unsaturated carboxylic acid and / or aliphatic unsaturated carboxylic acid derivative in component (ii) is generally 5 to 50% by weight, preferably 8 to 30% by weight, more preferably 10 to 25% by weight. is there. As the production method of component b), a known method for producing a styrene resin, for example, a bulk polymerization method, a solution polymerization method, a suspension polymerization method, an emulsion polymerization method or the like can be used. In general, a polymer having a weight average molecular weight of component b) of 50,000 to 500,000 can be used.

  For example, aliphatic unsaturated carboxylic acid ester of aliphatic unsaturated carboxylic acid ester-styrene copolymer is carbon such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, etc. C1 to C12, preferably C2 to C12 alcohol and acrylic acid, or methacrylic acid and C1 to C12, preferably C2 to C12 alcohol and acrylic acid, and α and β unsaturated. It is at least one selected from mono- or diesters of dicarboxylic acids such as fumaric acid, itaconic acid, maleic acid and the like and alcohols having C1-C12, preferably C2-C12. The content of the aliphatic unsaturated carboxylic acid ester in the aliphatic unsaturated carboxylic acid ester-styrene copolymer is generally 5 to 50% by weight, preferably 8 to 30% by weight, and more preferably 10 to 25% by weight. is there.

Moreover, the Vicat softening point in the aliphatic unsaturated carboxylic acid ester-styrene copolymer used for improving the low temperature shrinkage is 50 to 95 ° C, preferably 60 to 90 ° C, more preferably 65 to 85 ° C. It is recommended that The Vicat softening temperature is a value measured according to ASTM D-1525 (load: 1 Kg, heating rate: 2 ° C./min) using a test piece compression-molded to a thickness of 3 mm.
Particularly preferred aliphatic unsaturated carboxylic acid ester-styrene copolymer is a copolymer mainly composed of n-butyl acrylate and styrene, and the total amount of n-butyl acrylate and styrene is 50% by weight or more, more preferably. Is an aliphatic unsaturated carboxylic acid ester-styrene copolymer in which the total amount of n-butyl acrylate and styrene is 60% by weight or more. A heat-shrinkable film using an aliphatic unsaturated carboxylic acid ester-styrene copolymer mainly composed of n-butyl acrylate and styrene has good shrinkage and natural shrinkage.

  The c) rubber-modified styrenic polymer used in the present invention is obtained by polymerizing a mixture of a monomer copolymerizable with a vinyl aromatic hydrocarbon and an elastomer. As a polymerization method, suspension polymerization, emulsion polymerization, bulk Polymerization, bulk-suspension polymerization and the like are generally performed. Examples of the monomer copolymerizable with the vinyl aromatic hydrocarbon include α-methylstyrene, acrylonitrile, acrylic acid ester, methacrylic acid ester, maleic anhydride and the like. As the copolymerizable elastomer, natural rubber, synthetic isoprene rubber, butadiene rubber, styrene-butadiene rubber, high styrene rubber or the like is used.

  These elastomers are generally 3 to 50 parts by weight with respect to 100 parts by weight of vinyl aromatic hydrocarbon or a monomer copolymerizable therewith, or dissolved in latex or emulsion-like, bulk polymerization, bulk-suspension polymerization in latex form. Etc. A particularly preferable rubber-modified styrene polymer is an impact-resistant rubber-modified styrene polymer (HIPS). The rubber-modified styrenic polymer can be used as an agent for improving rigidity, impact resistance and slipperiness. A polymer having a weight average molecular weight of 50,000 to 500,000 can be used. The addition amount of the rubber-modified styrenic polymer is preferably 0.1 to 10 parts by weight in consideration of maintaining transparency.

As the vinyl aromatic hydrocarbon polymer used in the present invention, in particular, MFR (temperature 200 ° C. under G condition, load 5 kg) is 0.1 to 100 g / 10 min from the point of molding, preferably 0.5 to 50 g / 10 min and 1-30 g / 10 min are recommended.
In the block copolymer hydrogenated product and composition of the present invention, at least one selected from fatty acid amide, paraffin, hydrocarbon-based resin and fatty acid as a lubricant is added in an amount of 0.001 part by weight based on 100 parts by weight of the block copolymer hydrogenated product. By adding 01 to 5 parts by weight, preferably 0.05 to 4 parts by weight, more preferably 0.1 to 3 parts by weight, blocking resistance is improved.

  Examples of fatty acid amides include stearoamide, oleyl amide, erucyl amide, behen amide, mono- or bisamide of higher fatty acids, ethylene bis stearoamide, stearyl oleyl amide, N-stearyl erucamide, etc. Two or more types can be mixed and used. Examples of the paraffin and hydrocarbon resins include paraffin wax, microcrystalline wax, liquid paraffin, paraffin synthetic wax, polyethylene wax, composite wax, montan wax, hydrocarbon wax, silicone oil, etc. Two or more types can be mixed and used.

  Examples of fatty acids include saturated fatty acids, unsaturated fatty acids, N-substituted fatty acids and the like. That is, saturated fatty acids such as lauric acid, palmitic acid, stearic acid, behenic acid, hydroxystearic acid, unsaturated fatty acids such as oleic acid, erucic acid, ricinoleic acid, N-stearyl stearic acid, N-oleyl oleic acid, N- Stearyl oleic acid, N-oleyl stearic acid, N-stearyl erucic acid, N-oleyl palmitic acid, substituted fatty acids such as methylol stearic acid, methylol behenic acid, methylene bis stearic acid, ethylene biscapric acid, ethylene bis lauric acid, ethylene Saturation of bis-stearic acid, ethylene bisisostearic acid, ethylene bishydroxystearic acid, ethylene bisbehenic acid, hexamethylene bishydroxystearic acid, N, N′-distearyl adipic acid, N, N′-distearyl sebacic acid, etc. Unsaturated fatty acids such as fatty acid, ethylenebisoleic acid, hexamethylenebisoleic acid, N, N′-dioleyl adipic acid, N, N′-dioleyl sebacic acid, m-xylylene bisstearic acid, N, N There are '-distearylisophthalic acid and the like, but these can be used alone or in admixture of two or more.

The block copolymer hydrogenated composition and composition of the present invention includes at least one selected from benzophenone-based UV absorbers, benzotriazole-based UV absorbers, and hindered amine-based light stabilizers as UV absorbers and light stabilizers. The ultraviolet absorber and the light stabilizer are 0.05 to 3 parts by weight, preferably 0.05 to 2.5 parts by weight, more preferably 0.1 to 2 parts by weight, based on 100 parts by weight of the block copolymer hydrogenated product. By adding a part, light resistance is improved.
Examples of the benzophenone ultraviolet absorber include 2,4-dihydroxy-benzophenone, 2-hydroxy-4-methoxy-benzophenone, 2,2'-dihydroxy-4-methoxy-benzophenone, 2,2'-dihydroxy-4,4 '. -Dimethoxy benzophenone, 2-hydroxy-4-n-octoxy benzophenone, 2,2 ', 4,4'-tetrahydroxy benzophenone, 4-dodecyloxy-2-hydroxy benzophenone, 3,5-di-t- Butyl-4-hydroxybenzoyl acid, n-hexadecyl ester, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 1,4-bis (4-benzoyl-3-hydroxyphenoxy) butane, 1, 6-bis (4-benzoyl-3-hydroxyphenoxy) hexane etc. That.

  Examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-5′-methyl-phenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butyl-phenyl) benzo Triazole, 2- (2′-hydroxy-3′-t-butyl-5′-methyl-phenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t- Butyl-phenyl) -5-chloro-benzotriazole, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-amyl) Phenyl) benzotriazole, 2- [2′-hydroxy-3 ′-(3 ′, 4 ′, 5 ′, 6′-tetrahydrophthalimidomethyl) -5′-methylphenyl] benzotria 2-2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- [2-hydroxy-3, 5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (2-hydroxy-4-octyloxyphenyl) -2H-benzotriazole, 2- (2H-benzotriazol-2-yl) -4-methyl-6- (3,4,5,6-tetrahydrophthalimidylmethyl) phenol and the like.

  Examples of hindered amine light stabilizers include bis (2,2,6,6-tetramethyl-4-piperidyl) separate, bis (1,2,6,6,6-pentyl-4-piperidyl) separate, 1- [2- {3- (3,5-di-tert-butyl-4-hydroxydiphenyl) propionyloxy} ethyl] -4- {3- (3,5-di-tert-butyl-4-hydroxydiphenyl) ) Propionyloxy} -2,2,6,6-tetramethylpiperidine, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triasaspiro [4,5] decane- 2,4-dione, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, dimethyl-1- (2-hydroxyethyl) succinate) -4-hydroxy-2,2,6,6- Tetramethyl pipette Jin polycondensate thereof.

  Also, poly [[6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4-diyl] [(2,2,6,6-tetramethyl-4 -Piperidyl) imino] hexamethylene [[2,2,6,6-tetramethyl-4-piperidyl] imino]], poly [6-morpholino-s-triazine-2,4-diyl] [(2,2, 6,6-tetramethyl-4-piperidyl) imino] -hexamethylene [(2,2,6,6-tetramethyl-4-biperidyl) imino]], 2- (3,5-di-tert-butyl- 4-Hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), tetraxy (2,2,6,6-tetramethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate, tet Laxi (1,2,2,6,6, -pentamethyl-4-piperidyl) 1,2,3,4, -butanetetracarboxylate, 1,2,3,4-butanetetracarboxylic acid and 1,2 , 2,6,6-pentamethyl-4-piperidinol and a condensate of tridecyl alcohol.

  Furthermore, a condensate of 1,2,3,4-butanetetracarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol and tridecyl alcohol, 1,2,3,4-butanetetracarboxylic Acid, 1,2,2,6,6-pentamethyl-4-piperidinol and β, β, β, β-tetramethyl-3,9- (2,4,8,10-tetraoxaspiro [5,5] Undecane) condensate with diethanol, 1,2,3,4-butanetetracarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol and β, β, β, β-tetramethyl-3,9 -Condensation with (2,4,8,10-tetraoxaspiro [5,5] undecane) diethanol, N, N'-bis (3-aminopropyl) ethylenediamine · 2,4-bis [N-butyl- N- (1,2,2,6,6-Pendame Tyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, dibutylamine, 1,3,5-triazine, N, N-bis (2,2,6,6-tetramethyl -4-pipericyl-1,6-hexamethylenediamine / N-2,2,6,6-tetramethy-4-piperidyl) butylamine polycondensate, 1,2,2,6,6-tetramethyl-4- Pipericyl-methacrylate, 2,2,6,6-tetramethyl-4-pipericyl-methacrylate and the like.

  The block copolymer hydrogenated composition and composition of the present invention include 2- [1- (2-hydroxy-3,5-di-t-pentylphenyl) ethyl] -4,6-di-t- as a stabilizer. By adding 0.05 to 3 parts by weight, more preferably 0.1 to 2 parts by weight of pentylphenyl acrylate with respect to 100 parts by weight of the hydrogenated block copolymer, a gel suppressing effect can be obtained.

  The hydrogenated block copolymer and the block copolymer composition of the present invention include n-octadecyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-bis [(octylthio) methyl] -o-cresol, tetrakis [methylene-3- (3,5- Di-t-butyl-4-hydroxyphenyl) propionate] methane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 2, At least one phenol-based stabilizer such as 4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine; 0.05-3 parts by weight, 100 parts by weight of hydrogenated block copolymer, tris- (nonylphenyl) phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphite 2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,3,2] dioxaphosphin-6-yl] oxy] -N, N-bis [2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,3,2] dioxaphosphin-6-yl] oxy] -Ethyl] -ethanamine, tris (2,4-di-t-butylphenyl) phosphite and other organic phosphate-based and organic phosphite-based stabilizers based on 100 parts by weight of block copolymer hydrogenated product 0. It may be added 5 to 3 parts by weight.

Various polymers and additives can be added to the hydrogenated block copolymer and the composition of the present invention depending on the purpose. Suitable polymers include vinyl aromatic hydrocarbon and conjugated diene block copolymer elastomers or hydrogenated products thereof, and vinyl aromatic hydrocarbon and conjugated diene blocks different from the block copolymer hydrogenated products of the present invention. Copolymers and / or hydrogenated products thereof.
In the present invention, the block copolymer elastomer of vinyl aromatic hydrocarbon and conjugated diene or its hydrogenated product has a vinyl aromatic hydrocarbon content of less than 60% by weight, preferably 10 to 50% by weight. Those having the same structure as the block copolymer hydrogenated product can be used, and 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the block copolymer hydrogenated product of the present invention. By doing so, impact resistance, elongation, and the like can be improved.

In the hydrogenated block copolymer elastomer, the hydrogenation rate of the unsaturated double bond based on the conjugated diene can be arbitrarily selected according to the purpose and is not particularly limited. 70% or more, preferably 80% or more, more preferably 90% or more of the unsaturated double bonds based on the conjugated diene in the block copolymer elastomer may be hydrogenated, or only a part is hydrogenated. May be. When only a part is hydrogenated, the hydrogenation rate is preferably 10% or more and less than 70%, or 15% or more and less than 65%, and if desired, 20% or more and less than 60%.
The vinyl aromatic hydrocarbon and conjugated diene block copolymer different from the block copolymer hydrogenated product of the present invention and / or its hydrogenated product has a vinyl aromatic hydrocarbon content of 60 to 95% by weight, preferably Is 65 to 90% by weight, and those having the same structure as the block copolymer hydrogenated product of the present invention can be used, and 5 to 90 parts by weight based on 100 parts by weight of the block copolymer hydrogenated product of the present invention. The impact resistance, rigidity, elongation and the like can be improved by blending preferably 10 to 80 parts by weight.

  Other suitable additives include softeners such as coumarone-indene resins, terpene resins, oils, and plasticizers. Various stabilizers, pigments, antiblocking agents, antistatic agents, lubricants and the like can also be added. Examples of the antiblocking agent, antistatic agent and lubricant include fatty acid amide, ethylene bis-stearamide, sorbitan monostearate, saturated fatty acid ester of fatty acid alcohol, pentaerythritol fatty acid ester, etc. -T-butylphenyl salicylate, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzo Triazole, 2,5-bis- [5′-t-butylbenzoxazolyl- (2)] thiophene, and the like, compounds described in “Practical Handbook for Additives for Plastics and Rubber” (Chemical Industry Co., Ltd.) can be used. . These are generally used in the range of 0.01 to 5% by weight, preferably 0.05 to 3% by weight.

The block copolymer hydrogenated product of the present invention and the block copolymer composition comprising a block copolymer hydrogenated product and a vinyl aromatic hydrocarbon polymer are various molding materials such as sheets, films and injection molded products. Can be used for
The heat-shrinkable uniaxial or biaxially stretched film using the block copolymer hydrogenated product and the block copolymer composition of the present invention is obtained by converting the block copolymer hydrogenated product from a normal T die or a circular die into a flat shape. Or it extrudes at 150-250 degreeC, Preferably it is 170-220 degreeC in the shape of a tube, and the obtained unstretched product is substantially uniaxially stretched or biaxially stretched.
For example, in the case of uniaxial stretching, in the case of a film or sheet, it is stretched in the extrusion direction with a calendar roll or the like, or in a direction perpendicular to the extrusion direction with a tenter or the like, and in the case of a tube, in the extrusion direction or circumferential direction of the tube. Stretch. In the case of biaxial stretching, in the case of a film or sheet, the extruded film or sheet is stretched in the longitudinal direction with a metal roll or the like, and then stretched in the transverse direction with a tenter or the like. The tubes are stretched simultaneously or separately in the circumferential direction of the tube, that is, in a direction perpendicular to the tube axis.

  In the present invention, the stretching temperature is 60 to 160 ° C, preferably 80 to 155 ° C, more preferably 85 to 150 ° C, and the stretching ratio is 1.5 to 8 times, preferably 2 to 6 in the machine direction and / or the transverse direction. It is preferable to stretch it twice. The stretching temperature is 60 ° C. or higher from the viewpoint of breaking during stretching, and 110 ° C. or lower from the viewpoint of shrinkage characteristics. The draw ratio is 1.5 times or more from the viewpoint of heat shrinkage and 8 times or less from the viewpoint of stable production. In the case of biaxial stretching, the stretching ratios in the longitudinal direction and the transverse direction may be the same or different. The uniaxially stretched or biaxially stretched heat-shrinkable film is then subjected to heat treatment at 60 to 160 ° C., preferably 80 to 155 ° C. for a short time, for example, 3 to 60 seconds, preferably 10 to 40 seconds. It is also possible to implement means to prevent natural contraction below.

  In order to use the heat-shrinkable film thus obtained as a heat-shrinkable packaging material or a heat-shrinkable label material, the heat shrinkage rate at 80 ° C. in the stretching direction is 5 to 60%, preferably 10 It is -55%, More preferably, it is 15-50%. When the heat shrinkage ratio is within such a range, a heat shrinkable film having an excellent balance between the heat shrinkage ratio and the natural shrinkage ratio can be obtained. In the present invention, the heat shrinkage rate at 80 ° C. is a measure of low temperature shrinkage, and a uniaxially stretched film or a biaxially stretched film is a heat medium that does not impair the characteristics of molded products such as 80 ° C. hot water, silicone oil, and glycerin. It is the heat shrinkage rate in each stretching direction of the molded product when immersed in the interior for 5 minutes. In the present invention, it is recommended that the natural shrinkage rate of the heat shrinkable film itself is 2.5% or less, preferably 2.0% or less, more preferably 1.5% or less within the range of the heat shrinkage rate. The Here, the natural shrinkage ratio of the heat shrinkable film itself is a value calculated by an equation described later after leaving the heat shrinkable film in the range of the above heat shrinkage ratio at 35 ° C. for 5 days.

Furthermore, the uniaxially stretched or biaxially stretched film of the present invention needs to have a tensile elastic modulus in the stretching direction of 7000 to 30000 Kg / cm ² , preferably 10,000 to 25000 Kg / cm ² as a heat-shrinkable packaging material. The tensile modulus in the stretching direction is 7000 Kg / cm ² or more due to the problem of settling in the shrink wrapping process, and is 30000 Kg / cm ² or less due to the problem of impact resistance of the film.
When the uniaxially stretched or biaxially stretched film of the present invention is used as a heat-shrinkable packaging material, a temperature of 130 to 300 ° C., preferably 150 to 250 ° C., is used for several seconds to several minutes in order to achieve the desired heat shrinkage rate. Preferably, the heat shrinkage can be performed by heating for 1 to 60 seconds.

  The heat-shrinkable film of the present invention may be a multilayer laminate having at least two layers, preferably at least three layers. Specific examples of the usage form as the multilayer laminate include those disclosed in Japanese Patent Publication No. 3-5306. The hydrogenated block copolymer or composition of the present invention may be used for the intermediate layer and both outer layers. When the block copolymer hydrogenated product or composition of the present invention is used in a multilayer film, the layers other than the film layer using the block copolymer hydrogenated composition or the composition of the present invention are not particularly limited. The block copolymer hydrogenated product or composition of the present invention having a different composition or the like, the block copolymer other than the present invention and / or the hydrogenated product thereof, or the block copolymer other than the present invention and / or the hydrogenated product thereof. A multilayer laminate in which a composition of a product and the vinyl aromatic hydrocarbon polymer is combined may be used. In addition, polypropylene, polyethylene, ethylene polymer (ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, etc.) ionomer resin, nylon resin, polyester resin, poly Examples include at least one component selected from methyl methacrylate resin, ABS resin, the above-mentioned vinyl aromatic hydrocarbon polymer, and the like. Preferably, a block copolymer other than the present invention and / or a hydrogenated product thereof or a book is used. A block copolymer other than the invention and / or a hydrogenated product thereof and a composition of the vinyl aromatic hydrocarbon polymer, and the vinyl aromatic hydrocarbon polymer.

  In the heat-shrinkable multilayer film preferred in the present invention, the layer comprising the hydrogenated block copolymer of the present invention or the composition is at least one layer of the multilayer film, and the heat shrinkage rate at 80 ° C. in the stretching direction is 5-60. %, Preferably 10-55%, more preferably 15-50%. The hydrogenated block copolymer used in the heat-shrinkable multilayer film satisfies the requirements defined in the present invention, and has a molecular weight (polystyrene equivalent molecular weight) of 40,000 to 300,000 in gel permeation chromatography (GPC) measurement. Preferably, a block copolymer hydrogenated product having at least two peaks in the range of 45,000 to 280,000, more preferably 50,000 to 280,000 is preferable, and heat shrinkage excellent in natural shrinkage resistance and hot water fusion resistance Can be obtained.

  The block copolymer hydrogenated product that can be suitably used for the heat-shrinkable multilayer film has excellent balance of physical properties such as rigidity and impact resistance by having at least two peaks in the molecular weight range of 40,000 to 300,000. . Such hydrogenated block copolymer can be obtained by mixing block copolymers having different compositions and molecular weights of vinyl aromatic hydrocarbon and conjugated diene, or by adjusting the molecular weight and polymerizing in the same reactor. it can. Adjustment of molecular weight in the same reactor includes a method of adding an initiator a plurality of times, a method of adding a polyfunctional coupling agent to a polymerization active terminal, or a method of inactivating a part of the active terminal during polymerization. . When inactivating a part of the active terminal during the polymerization, a method of adding an active hydrogen-containing compound such as alcohol, phenolic compound, carboxylic acid, amine compound, water, ketone compound, epoxy compound or the like is common.

The ratio of the component showing at least two peaks present in the block copolymer hydrogenated product that can be suitably used for the heat-shrinkable multilayer film is such that the weight ratio of the component showing the maximum molecular weight and the other components is 10/90. ˜90 / 10, preferably 20/80 to 80/20, more preferably 70/30 to 30/70. These weight ratios can be ascertained from the weight ratio of each component to be mixed when mixing, and the polymerization conditions when polymerizing in the same reactor. Moreover, it can also grasp | ascertain from the area ratio of each component in a gel permeation chromatogram.
The heat shrinkable multilayer film of the present invention has a heat shrinkage rate of 80 ° C. in the stretching direction of 5 to 60%, preferably 10 to 55%, more preferably 15 to 50%, and a tensile elastic modulus in the drawing direction of 7000. It is also possible to obtain a heat-shrinkable multilayer film of ˜30000 Kg / cm ² , preferably 10,000 to 25000 Kg / cm ² .

The thickness of the heat-shrinkable film and heat-shrinkable multilayer film of the present invention is 10 to 300 μm, preferably 20 to 200 μm, more preferably 30 to 100 μm, and the thickness ratio between the inner layer and both surface layers is 5/95 to 45. / 55, preferably 10/90 to 35/65 is recommended.
The heat-shrinkable film of the present invention can be used for various uses such as packaging of fresh foods, confectionery, clothing, stationery, etc. by making use of the characteristics. As a particularly preferred application, letters and designs are printed on a uniaxially stretched film of a block copolymer defined in the present invention, and then the surface of a packaged object such as a plastic molded product, a metal product, a glass container, or a porcelain is thermally contracted. It can be used as a material for so-called heat-shrinkable labels that are used in close contact.

  In particular, the uniaxially stretched heat-shrinkable film of the present invention is excellent in solvent resistance, low-temperature shrinkage, rigidity and natural shrinkage. , Materials having extremely different coefficients of thermal expansion and water absorption from the block copolymer of the present invention, such as metals, porcelain, glass, paper, polyethylene, polypropylene, polybutene, and other polyolefin resins, polymethacrylate resins, polycarbonate It can be suitably used as a heat-shrinkable label material for containers using at least one selected from polyester resins such as polyethylene resins, polyethylene terephthalate, polybutylene terephthalate, and polyamide resins as constituent materials.

  The material constituting the plastic container in which the heat-shrinkable film of the present invention can be used is polystyrene, rubber-modified impact-resistant polystyrene (HIPS), styrene-butyl acrylate copolymer, styrene-acrylonitrile in addition to the above resins. Copolymer, styrene-maleic anhydride copolymer, acrylonitrile-butadiene-styrene copolymer (ABS), methacrylate-butadiene-styrene copolymer (MBS), polyvinyl chloride resin, polyvinyl chloride resin , Phenol resin, urea resin, melamine resin, epoxy resin, unsaturated polyester resin, silicone resin and the like. These plastic containers may be a mixture of two or more resins or a laminate.

  When the heat-shrinkable film of the present invention is used as a heat-shrinkable label material, the heat shrinkage rate at 80 ° C. in the direction orthogonal to the stretching direction is less than 20%, preferably 10% or less. Therefore, uniaxial stretching as a heat-shrinkable label in the present invention means that the heat shrinkage rate at 80 ° C. in the drawing direction is 5 to 60% and the heat shrinkage rate in the direction orthogonal to the drawing direction is less than 20%. This refers to performing a stretching process.

  Examples of the present invention will be described below, but these do not limit the scope of the present invention. Table 1 shows hydrogenated block copolymers, and Table 2 shows styrene-n-butyl acrylate copolymers and general-purpose polystyrene (GPPS) as vinyl aromatic hydrocarbon polymers.

(Preparation of block copolymer hydrogenated products A-1 to A-6)
The block copolymer before hydrogenation uses n-butyllithium in a cyclohexane solvent as a catalyst, tetramethylethylenediamine as a randomizing agent, styrene content (% by weight), block rate (% by weight) shown in Tables 1 and 2. ) And a block copolymer having a molecular weight of block styrene. Styrene content is the addition amount of styrene and butadiene (including isoprene if isoprene is included), the block ratio is the styrene content of segment A and segment B, and the molecular weight of block styrene is the styrene content of segment A and segment B The amount ratio was adjusted. In preparing the block copolymer, a monomer diluted with cyclohexane to a concentration of 20% by weight was used.
The hydrogenation catalyst was charged with 1 liter of dried and purified cyclohexane in a nitrogen-substituted reaction vessel, 100 mmol of bis (η5-cyclopentadienyl) titanium dichloride was added, and 200 mmol of trimethylaluminum was added while stirring sufficiently. The hydrogenation catalyst which added the n-hexane solution containing and made it react at room temperature for about 3 days was used.

1) Block copolymer hydrogenated product A-1
Using an autoclave with a stirrer, 0.055 parts by weight of n-butyllithium and 0.05 parts by weight of tetramethylethylenediamine were added to a cyclohexane solution containing 10 parts by weight of 1,3-butadiene under a nitrogen gas atmosphere, and at 70 ° C. Polymerized for 20 minutes. Next, a cyclohexane solution containing 10 parts by weight of styrene and 2 parts by weight of 1,3-butadiene was continuously added for 15 minutes to polymerize at 70 ° C., and then the process of holding for 5 minutes was repeated 5 times.
Next, a cyclohexane solution containing 30 parts by weight of styrene was added and polymerized at 70 ° C. for 35 minutes. Next, 100 ppm of titanium as a titanium per 100 parts by weight of the block copolymer was added to the solution of the block copolymer obtained above, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C. . Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the block copolymer. Thereafter, the solvent was removed to obtain a hydrogenated block copolymer. The hydrogenation rate of the block copolymer hydrogenated product A-1 was adjusted by the amount of hydrogen so that the hydrogenation rate was 96%.

2) Block copolymer hydrogenated product A-2 to A-5
Block copolymer hydrogenated products A-2 to A-5 were prepared in the same manner as A-1.
3) Block copolymer hydrogenated product A-6
Using an autoclave equipped with a stirrer, 0.065 parts by weight of a cyclohexane solution containing 15 parts by weight of styrene and n-butyllithium was added to 100 parts by weight of all monomers used in a nitrogen gas atmosphere, and polymerized at 75 ° C. for 30 minutes. Next, a cyclohexane solution containing 17 parts by weight of 1,3-butadiene was added and polymerized at 75 ° C. for 30 minutes. Next, a cyclohexane solution containing 0.3 moles of tetramethylethylenediamine is added to n-butyllithium added previously, and then a cyclohexane solution containing 40 parts by weight of styrene and 13 parts by weight of 1,3-butadiene is added. The polymer was continuously added for 5 minutes and polymerized at 70 ° C., and held for 10 minutes. Next, a cyclohexane solution containing 15 parts by weight of styrene was added and polymerized at 70 ° C. for 30 minutes.

Next, 100 ppm of titanium as a titanium per 100 parts by weight of the block copolymer was added to the solution of the block copolymer obtained above, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C. . Methanol is then added, and then octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer is 0.3 parts by weight with respect to 100 parts by weight of the block copolymer hydrogenated product. Part was added.
The hydrogenation rate of the obtained block copolymer hydrogenated product A-7 was 98%, the crystallization peak temperature was 62 ° C., and the crystallization peak heat amount was 17.5 J / g.

(Preparation of aliphatic unsaturated carboxylic acid ester-styrene copolymer)
Styrene-n-butyl acrylate copolymers B-1 and B-2 were prepared by adding 5 kg of styrene and n-butyl acrylate or methyl methacrylate to a 10 L autoclave with a stirrer at the ratio shown in Table 2, and simultaneously adding 0 .3 kg and a predetermined amount of 1,1 bis (t-butylperoxy) cyclohexane to adjust MFR, and after polymerization at 110 to 150 ° C. for 2 to 10 hours, unreacted styrene and acrylic acid n- Butyl and ethylbenzene were recovered and produced. The MFR of B-1 obtained was 3.0 g / 10 min, and the MFR of B-2 was 2.6 g / 10 min.

(Measurement and evaluation method)
The measurement and evaluation described in Examples and Comparative Examples were performed by the following methods.
1) Styrene content The styrene content of the block copolymer hydrogenated product was measured using an ultraviolet spectrophotometer (device name: UV-2450; manufactured by Shimadzu Corporation).

2) Block ratio A method of oxidatively decomposing a block copolymer before hydrogenation with tertiary butyl hydroperoxide using osmium tetroxide as a catalyst (IM KOLTHOFF, et al., J. Polym. Sci. 1, 429) (Method described in (1946)), and the block styrene content was measured. Further, the block ratio is calculated by the following formula using the vinyl aromatic hydrocarbon polymer block component obtained by the same method (however, the vinyl aromatic hydrocarbon polymer component having an average degree of polymerization of about 30 or less is excluded). I asked for it.
Block ratio (% by weight) = (weight of vinyl aromatic hydrocarbon polymer block in block copolymer / weight of total vinyl aromatic hydrocarbon in block copolymer) × 100

3) Block Styrene Peak Molecular Weight The vinyl aromatic hydrocarbon polymer block component obtained in 2) above was dissolved in a tetrahydrofuran solvent and obtained by a conventional method using gel permeation chromatography (GPC). The peak molecular weight was measured by GPC measurement of monodisperse polystyrene for GPC, and the peak molecular weight was read from the measured chromatograph based on a calibration curve between the peak count number and the number average molecular weight of the monodisperse polystyrene.

4) Amount of 35,000 or less of block styrene The total area of the molecular weight distribution curve was determined from the chromatograph obtained in 3) above, and the value obtained by dividing the area of the molecular weight of 35000 or less by the total area of the molecular weight distribution curve was expressed as a percentage.
5) Number average molecular weight The molecular weight of the hydrogenated block copolymer was measured using a GPC apparatus (manufactured by Waters, USA). Tetrahydrofuran was used as the solvent, and the measurement was performed at 35 ° C. The number average molecular weight was calculated | required using the analytical curve created using the commercially available standard polystyrene whose weight average molecular weight and number average molecular weight are known.

6) Vinyl bond content and hydrogenation rate Using a block copolymer hydrogenated product, the amount was measured with a nuclear magnetic resonance apparatus (device name: DPX-400; manufactured by BRUKER, Germany).
7) Crystallization peak and crystallization peak calorie The crystallization peak and crystallization peak calorie of the hydrogenated block copolymer were measured by DSC (device name: DSC3200S; manufactured by Mac Science). The temperature was increased from room temperature to 150 ° C. at a rate of temperature increase of 30 ° C./min, and then the temperature was decreased to −100 ° C. at a rate of temperature decrease of 10 ° C./min to determine the presence or absence of a crystallization peak. . Further, when there was a crystallization peak, the temperature at which the peak appeared was defined as the crystallization peak temperature, and the crystallization peak calorie was measured.

8) Shrinkage The 80 ° C. shrinkage was calculated by the following equation by immersing the stretched film in 80 ° C. silicone oil for 5 minutes.
Thermal contraction rate (%) = (L−L1) / L × 100,
L: Length before contraction, L1: Length after contraction.
9) Natural shrinkage rate This is a value calculated by the following formula after leaving a stretched film having a shrinkage rate of 40% measured at 80 ° C for 5 days at 35 ° C.
Natural shrinkage (%) = (L2−L3) / L2 × 100,
L2: length before being left, L3: length after being left.
The smaller the natural shrinkage rate, the better the natural shrinkage.
Further, the natural shrinkage ratio of the heat-shrinkable multilayer film was calculated by the following formula after leaving the heat-shrinkable multilayer film having an 80 ° C. shrinkage of 30% at 35 ° C. for 5 days.

10) Tensile modulus and elongation at break Based on JIS K-6732, the film was measured in the stretching direction at a tensile speed of 5 mm / min. The test piece had a width of 12.7 mm and a gap between marked lines of 50 mm. The measurement temperature was 23 ° C. The unit is Kg / cm ² .
11) Puncture impact strength Measured according to JIS P-8134. The unit is Kg · cm.
12) Haze
Liquid paraffin was applied to the surface of the sheet before stretching and measured according to ASTM D1003.

13) Blocking property Two heat-shrinkable multilayer films measuring 5 cm in length and 5 cm in width were overlapped, applied with a weight of 100 g / cm ² G, and allowed to stand at 40 ° C. for 7 days, and the blocking state of the film was visually determined.
<Criteria>
○: Blocking is not recognized.
X: Blocking is recognized.
14) Warm water fusing property The stretched film was wound around a glass bottle having a diameter of about 8 cm, left in 70 ° C. warm water for 5 minutes, and the fused state of the film was visually determined. Judgment criteria are that ◎ is not fused at all, ◯ is slightly fused but leaves immediately, and × is fused and does not leave immediately.

15) Solvent resistance 1 mL of a solvent having a 50/50 ratio of ethyl acetate to isopropyl alcohol was dropped between the second and third sheets of 5 cm × 5 cm (vertical × horizontal) stretched films, and 30 The state of fusion between the films was visually determined in the state of being superposed at 24 ° C. for 24 hours. As for the judgment criteria, ◯ is not fused at all, and X is fused and not separated.
16) FE
The block copolymer hydrogenated material was continuously formed into a 0.3 mm thick sheet for 6 hours using a 40 mm sheet extruder at an extrusion temperature of 240 ° C., and the sheet area was 300 cm after 5 minutes and 6 hours from the start of operation. ^The number of FEs of 0.5 mm or more per ² was counted and evaluated by the difference in the number of FEs.

[Examples 1 to 6 and Comparative Examples 1 and 2]
The heat shrinkable film performance was measured using the block copolymers A-1 to A-6 shown in Table 1 and other block copolymers B-4 (styrene-butadiene block copolymer tufprene manufactured by Asahi Kasei Corporation). 126) and B-5 (styrene-butadiene hydrogenated block copolymer Tuftec 1041 manufactured by Asahi Kasei Co., Ltd.) and styrene-n-butyl acrylate copolymers shown in Table 2: B-1, B-2, general purpose A composition of polystyrene: B-3 (A & M polystyrene 685, manufactured by A & M Styrene Co., Ltd.) was molded into a sheet having a thickness of 0.25 mm at 200 ° C. using a 40 mm extruder by the formulation shown in Table 3, and then Stretching temperature is 100 ° C. (Comparative Example 5 is stretched at 110 ° C. because it cannot be stretched at 100 ° C.) Using a tenter, the horizontal axis is stretched uniaxially at a stretch ratio of 5 times to obtain a thickness. To obtain a heat-shrinkable film of 60 [mu] m. Table 3 shows the film performance of the heat-shrinkable film. The performance of the heat-shrinkable film of the present invention is as follows: rigidity represented by tensile modulus, low-temperature shrinkage represented by 80 ° C. shrinkage, natural shrinkage, impact resistance represented by puncture impact strength, hot water fusion It can be seen that the composition is excellent in transparency and transparency represented by Haze. In addition, the sheet | seat and film performance shown in Table 3 were performed by said method.

[Example 7]
A three-layer sheet having the composition shown in Table 4 as an inner layer and front and back layers was extruded from a T die, stretched 1.2 times in the longitudinal direction, and formed into a sheet having a thickness of 0.25 mm. Subsequently, the film was stretched 5 times in the transverse direction by a tenter to obtain a heat-shrinkable film having a thickness of about 50 μm. The thickness ratio (%) between the inner layer and the surface layer / back layer was 15 (surface layer) / 70 (inner layer) / 15 (back layer). The performance of the obtained three-layer heat-shrinkable film is shown in Table 4. In addition, 0.2 parts by weight of Adeka Stub LA-32 (manufactured by Asahi Denka Kogyo Co., Ltd.) as an ultraviolet absorber and 0.2 parts by weight of stearoamide as a lubricant for 100 parts by weight of the composition of the front and back layers, respectively. Added in increments.

  The heat-shrinkable film using the hydrogenated block copolymer of the present invention is transparent, and is excellent in solvent resistance, rigidity, natural shrinkage, low-temperature shrinkage, hot-water fusion, and impact resistance. Can be achieved at the same time, and can be suitably used for beverage container packaging, cap seals, various labels, and the like.

Claims (15)

A hydrogenated block copolymer having a weight ratio of vinyl aromatic hydrocarbon to conjugated diene of 60/40 to 95/5 and a number average molecular weight of 3 to 500,000 as measured by gel permeation chromatography (GPC). The vinyl aromatic hydrocarbon block ratio of the vinyl aromatic hydrocarbon incorporated in the hydrogenated product is 25 to 90 % by weight, and the vinyl aromatic hydrocarbon polymer block in the hydrogenated product has a molecular weight of 35,000 or less. Hydrogenated block copolymer for heat-shrinkable film , wherein the proportion of the aromatic hydrocarbon polymer block is less than 40% by weight of the total vinyl aromatic hydrocarbon polymer block . The block for heat-shrinkable film according to claim 1, wherein at least one vinyl aromatic hydrocarbon polymer block having a peak molecular weight in the range of molecular weight 35,000 to 150,000 is incorporated in the hydrogenated block copolymer. Copolymer hydrogenated product. The content of the short-chain vinyl aromatic hydrocarbon polymerized moiety in which the number of vinyl aromatic hydrocarbon units is in the range of 1 to 3 with respect to the total amount of vinyl aromatic hydrocarbon constituting the hydrogenated block copolymer is 1 to 25 The hydrogenated block copolymer for heat-shrinkable film according to claim 1 or 2, wherein the hydrogenated block copolymer has a weight% . In the block copolymer hydrogenated product, (i) a copolymer block composed of isoprene and 1,3-butadiene, (ii) a copolymer block composed of isoprene and vinyl aromatic hydrocarbon, and (iii) isoprene, 1, At least one polymer block selected from the group (i) to (iii) of a copolymer block consisting of 3-butadiene and vinyl aromatic hydrocarbon is incorporated, and in the block copolymer hydrogenated product The block copolymer hydrogenated product for heat-shrinkable film according to any one of claims 1 to 3, wherein the weight ratio of butadiene to isoprene is 3/97 to 90/10 . Heat-shrinkable film comprising a heat-shrinkable film for a block copolymer hydrogenated product according to claim 1. The heat-shrinkable block copolymer hydrogenated product according to any one of claims 1 to 4 is stretched, and the heat shrinkage rate at 80 ° C in the stretching direction is 5 to 60%, and the tensile modulus in the stretching direction is 5%. A heat-shrinkable film having a molecular weight of 7000 to 30,000 Kg / cm2. A component (A) which is a hydrogenated block copolymer for heat shrinkage according to any one of claims 1 to 4 and a component (B) which is a vinyl aromatic hydrocarbon polymer, ) And component (B) in a weight ratio of 99.9 / 0.1 to 20/80. A heat-shrinkable film comprising the composition of claim 7 . A heat-shrinkable film obtained by stretching the composition according to claim 7 and having a heat shrinkage rate of 5 to 60% at 80 ° C in the stretching direction and a tensile elastic modulus in the stretching direction of 7000 to 30000 Kg / cm ² . The heat-shrinkable film according to claim 8 or 9, wherein the vinyl aromatic hydrocarbon polymer of component (B) is at least one selected from the following a) to c) .
a) Styrenic polymer b) At least one aliphatic unsaturated carboxylic acid selected from vinyl aromatic hydrocarbons and aliphatic unsaturated carboxylic acids, aliphatic unsaturated carboxylic acid anhydrides and aliphatic unsaturated carboxylic acid esters Copolymer with acid or derivative thereof c) Rubber-modified styrenic polymer 5. At least one lubricant selected from fatty acid amide, paraffin, hydrocarbon-based resin, and fatty acid is added to 100 parts by weight of the hydrogenated block copolymer for heat shrinkage according to any one of claims 1 to 4. The heat-shrinkable film according to any one of claims 5, 6, 9 and 10, wherein 0.01 to 5 parts by weight are added . 2- [1- (2-hydroxy-3,5-di-t-pentylphenyl) based on 100 parts by weight of the heat-shrinkable block copolymer hydrogenated product according to any one of claims 1 to 4. Ethyl] -4,6-di-t-pentylphenyl acrylate, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4- 12. At least one stabilizer selected from bis [(octylthio) methyl] -o-cresol is added in an amount of 0.05 to 3 parts by weight , according to any one of claims 5, 6, 9, 10 and 11. The heat-shrinkable film described. From 100 parts by weight of the heat-shrinkable block copolymer hydrogenated product according to any one of claims 1 to 4 , from a benzophenone ultraviolet absorber, a benzotriazole ultraviolet absorber, and a hindered amine light stabilizer. The heat-shrinkable film according to claim 5 , wherein 0.05 to 3 parts by weight of at least one selected ultraviolet absorber or light stabilizer is added . The heat-shrinkable block copolymer hydrogenated product according to any one of claims 1 to 4 or the layer made of the composition according to claim 10 is used as at least one layer of a multilayer film, and 80 ° C in the stretching direction. The heat-shrinkable multilayer film is characterized by having a heat shrinkage ratio of 5 to 60%. The heat-shrinkable multilayer film according to claim 14 , which has a tensile elastic modulus in the stretching direction of 7000 to 30,000 Kg / cm2.