JP7758577B2 - Laminate and manufacturing method thereof - Google Patents

Description

The present invention relates to a laminate having a layer containing a 4-methyl-1-pentene polymer and a method for producing the same.

Compared to polyethylene and polypropylene, 4-methyl-1-pentene polymers have superior properties, including heat resistance, transparency, light weight, steam resistance, release properties, stain resistance, gas permeability, and electrical properties. Because these excellent properties can be imparted to other materials, laminates composed of layers of 4-methyl-1-pentene polymers and layers of other materials are expected to be used in a variety of fields, including food containers, secondary materials for electronic and information components, laboratory equipment, stationery, crosslinking process materials, release films, films for electronic and information components, food packaging, and synthetic paper.

A cast film method is known as a method for producing a laminated film using a 4-methyl-1-pentene polymer. However, the cast film method has problems such as only being able to produce a flat film or sheet, and the thickness of the edge portion of the film is likely to be uneven, and the uneven portion (edge portion) must be removed by trimming, resulting in a low yield.
Therefore, there has been a demand for a laminate having a layer containing a 4-methyl-1-pentene polymer and having a uniform thickness, and in particular for a laminate obtainable by inflation film molding.

Patent Document 1 describes the production of a multilayer inflation film, which is a laminate of a layer of a 4-methyl-1-pentene copolymer and a layer of a thermoplastic resin other than a 4-methyl-1-pentene copolymer, by setting the temperature during molding within a specific range and extruding the film in an upward direction.

Patent Document 2 proposes a technology for improving the stretchability of 4-methyl-1-pentene polymers by using a resin composition containing two types of 4-methyl-1-pentene polymers with different melt flow rates (MFR), and indicates that the resin composition can be used for blow molding using a mold.

Japanese Patent Application Laid-Open No. 2001-62893 Japanese Patent Application Laid-Open No. 2003-292704

However, since 4-methyl-1-pentene polymers generally have poor stretchability, it is difficult to produce a laminate having a layer containing a 4-methyl-1-pentene polymer by inflation film molding involving stretching, even if the production method described in Patent Document 1 is adopted.
Furthermore, the resin composition described in Patent Document 2 has a problem that, even if it can be blow-molded, it has insufficient bubble stability when subjected to inflation molding, making molding difficult. Therefore, further improvement is required in order to combine a resin composition containing a 4-methyl-1-pentene polymer with other materials and subject it to inflation film molding involving stretching to produce a laminate with a uniform thickness.

Furthermore, for example, when producing a laminate having a layer containing a 4-methyl-1-pentene polymer and a layer containing a polyolefin, the melting point of a typical 4-methyl-1-pentene polymer is approximately 220 to 250°C, while the melting points of polyolefins are around 120°C for polyethylene and around 150°C for polypropylene, resulting in a significant difference in melting points. If the molding temperature is set to match the resin with a high melting point in order to fully melt the resins of both layers, problems such as deterioration of the resin with a low melting point can occur. On the other hand, if the molding temperature is set to match the resin with a low melting point, the resin with a high melting point will not melt, resulting in problems such as molding being impossible. This makes it difficult to set the molding temperature, making it difficult to produce a laminate using laminate inflation molding, which simultaneously molds each layer.

An objective of the present invention is to provide a laminate that has a layer containing a 4-methyl-1-pentene polymer and a layer containing another thermoplastic resin, has little variation in film thickness, good film thickness precision (thickness/thinness precision), and is heat resistant. Another objective of the present invention is to provide a method for producing such a laminate by inflation molding of a 4-methyl-1-pentene polymer and another thermoplastic resin, which enables inflation molding of the laminate and involves stretching the film.

In view of the above circumstances, the present inventors have conducted extensive research and found that the above problems can be solved by using a specific 4-methyl-1-pentene polymer composition in a layer containing a 4-methyl-1-pentene polymer, thereby completing the present invention.
The present invention relates to, for example, the following items [1] to [8].

[1] an X layer containing a 4-methyl-1-pentene polymer composition (X) that satisfies the following requirements (X-1) to (X-4);
and a Y layer containing a thermoplastic resin (Y).
Requirement (X-1): The density measured in accordance with JIS K7112 (density gradient tube method) is 0.82 to 0.88 g/m ³ .
Requirement (X-2): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 190°C to 220°C.
Requirement (X-3): The enthalpy of fusion ΔH is less than 35 J/g.
Requirement (X-4): The crystallization half time at 215°C measured by DSC using the following measurement method is 220 seconds or more, or cannot be measured.
Method for measuring the crystallization half time: Using a DSC8500 manufactured by PerkinElmer Co., Ltd., the temperature is increased from 30°C to 280°C at a heating rate of 500°C/min, the temperature is maintained for 10 minutes, and then the temperature is decreased to 215°C at a cooling rate of 500°C/min, and the crystallization half time at 215°C is measured.

[2] The laminate according to [1], wherein the 4-methyl-1-pentene polymer composition (X) satisfies the following requirements (X-5) and (X-6):
Requirement (X-5): The content of structural units derived from 4-methyl-1-pentene is 90.0 mol% or more and less than 100 mol%, and the content of structural units derived from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is more than 0 mol% and 10.0 mol% or less.
Requirement (X-6): The intrinsic viscosity [η] measured in decalin at 135° C. is 0.5 to 8.0 dl/g.

[3] The laminate according to [1] or [2], wherein the 4-methyl-1-pentene polymer composition (X) satisfies the following requirement (X-7):
Requirement (X-7): The melt tension (MT) measured at 260°C is 25 mN or more.

[4] The laminate according to any one of [1] to [3], wherein the thermoplastic resin (Y) is polyethylene or polypropylene.
[5] The laminate according to any one of [1] to [4], having a thickness of 0.1 to 100 μm.
[6] The laminate according to any one of [1] to [5], which is an inflation film.
[7] The laminate according to any one of [1] to [6], which is for packaging.

[8] A method for producing a laminate, comprising a step of subjecting a 4-methyl-1-pentene polymer composition (X) satisfying the following requirements (X-1) to (X-4) and a thermoplastic resin (Y) to laminate inflation molding under conditions such that the expansion ratio (bubble ratio) exceeds 1.0 and the molding temperature is lower than 250°C:
Requirement (X-1): The density measured in accordance with JIS K7112 (density gradient tube method) is 0.82 to 0.88 g/m ³ .
Requirement (X-2): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 190°C to 220°C.
Requirement (X-3): The enthalpy of fusion ΔH is less than 35 J/g.
Requirement (X-4): The crystallization half time at 215°C measured by DSC using the following measurement method is 220 seconds or more, or cannot be measured.
Method for measuring the crystallization half time: Using a DSC8500 manufactured by PerkinElmer Co., Ltd., the temperature is increased from 30°C to 280°C at a heating rate of 500°C/min, the temperature is maintained for 10 minutes, and then the temperature is decreased to 215°C at a cooling rate of 500°C/min, and the crystallization half time at 215°C is measured.

The present invention provides a laminate that has a layer containing a 4-methyl-1-pentene polymer and a layer containing another thermoplastic resin, has little variation in film thickness, good film thickness precision (thickness/thinness precision), and is heat resistant. The present invention also enables inflation molding of a laminate of a 4-methyl-1-pentene polymer and another thermoplastic resin, and provides a method for producing the laminate by inflation film molding involving stretching.

The present invention will be described in further detail below.
Laminate
The laminate of the present invention includes an X layer containing a 4-methyl-1-pentene polymer composition (X) and a Y layer containing a thermoplastic resin (Y).

<4-Methyl-1-pentene Polymer Composition (X)>
The 4-methyl-1-pentene polymer composition (X) according to the present invention contains at least one 4-methyl-1-pentene polymer. In the present invention, the 4-methyl-1-pentene polymer is a polymer or copolymer having a structural unit derived from 4-methyl-1-pentene, and is a homopolymer of 4-methyl-1-pentene or a copolymer of 4-methyl-1-pentene with a monomer copolymerizable with 4-methyl-1-pentene. Preferred examples of the copolymer include copolymers of 4-methyl-1-pentene with one or more olefins selected from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene).

Examples of the α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-heptadecene, 1-octadecene, and 1-eicosene. Among ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene), α-olefins having 10 to 20 carbon atoms are preferred, and α-olefins having 10 to 18 carbon atoms are more preferred, from the viewpoint of obtaining polymer compositions with excellent moldability. Specifically, 1-decene, 1-tetradecene, 1-hexadecene, and 1-octadecene are preferred. Furthermore, for example, it is preferable to use 1-hexadecene and 1-octadecene in combination.

In the 4-methyl-1-pentene polymer, the content of the structural units derived from ethylene and an α-olefin having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) may be in any range as long as the amount of the structural units in the entire 4-methyl-1-pentene polymer contained in the entire 4-methyl-1-pentene polymer composition (X) falls within a desired range. When the 4-methyl-1-pentene polymer composition (X) contains a plurality of 4-methyl-1-pentene polymers, the content of each individual polymer is not necessarily limited. However, the content is usually 20 mol % or less, preferably 10 mol % or less, more preferably 0.1 to 10 mol %, and even more preferably 0.2 to 8 mol %, relative to 100 mol % of all structural units constituting the 4-methyl-1-pentene polymer.
In addition, the content of structural units derived from 4-methyl-1-pentene in 100 mol % of all structural units constituting the 4-methyl-1-pentene polymer is usually 80 mol % or more, preferably 90 mol % or more.

The 4-methyl-1-pentene polymer may further contain structural units derived from other polymerizable compounds other than 4-methyl-1-pentene, ethylene, and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene), provided that the objectives of the present invention are not impaired. Examples of other polymerizable compounds include vinyl compounds having a cyclic structure such as styrene, vinylcyclopentene, vinylcyclohexane, and vinylnorbornane; vinyl esters such as vinyl acetate; unsaturated organic acids or derivatives thereof such as maleic anhydride; conjugated dienes such as butadiene, isoprene, pentadiene, and 2,3-dimethylbutadiene; 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene. Examples of non-conjugated polyenes include dicyclopentadiene, cyclohexadiene, dicyclooctadiene, methylenenorbornene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, and 2-propenyl-2,2-norbornadiene.

In the 4-methyl-1-pentene polymer, the content of structural units derived from polymerizable compounds other than 4-methyl-1-pentene, ethylene, and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is usually 10 mol % or less, preferably 5 mol % or less, and more preferably 3 mol % or less, based on 100 mol % of all structural units constituting the copolymer.
The 4-methyl-1-pentene polymer can be produced, for example, by a method for producing a 4-methyl-1-pentene polymer described later. Alternatively, commercially available 4-methyl-1-pentene polymers can be used alone or in combination as long as the 4-methyl-1-pentene polymer composition (X) satisfies the properties described later.

The 4-methyl-1-pentene polymer composition (X) according to the present invention may contain one of the above-mentioned 4-methyl-1-pentene polymers alone, or may contain a combination of two or more of them.

[0044] The 4-methyl-1-pentene polymer constituting the 4-methyl-1-pentene polymer composition (X) can be obtained, for example, by polymerizing 4-methyl-1-pentene, and, if necessary, ethylene and an α-olefin having 3 to 20 carbon atoms, and, if necessary, further the other polymerizable monomers described above. The 4-methyl-1-pentene polymer constituting the 4-methyl-1-pentene polymer composition (X) of the present invention can be suitably produced by carrying out the polymerization in the presence of a metallocene catalyst.

Examples of metallocene catalysts include those described in WO 01/53369, WO 01/27124, JP 3-193796 A, JP 02-41303 A, WO 06/025540 A, and WO 2013/099876 A.

Examples of metallocene catalysts include:
a metallocene compound (a);
and a support (b).

<<Metallocene Compound (a)>>
The metallocene compound (a) is represented by, for example, general formula (1) or (2).

The meanings of the symbols in the general formula (1) or (2) are as follows:
R ¹ to R ¹⁴ are each independently a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group, or a silicon-containing group. Adjacent substituents R ¹ to R ⁴ may be bonded to each other to form a ring. Adjacent substituents R ⁵ to R ¹² may be bonded to each other to form a ring.

Y is a carbon atom or a silicon atom.
A is a divalent hydrocarbon group having 2 to 20 carbon atoms which may contain an unsaturated bond and/or an aromatic ring. A may contain two or more ring structures including the ring formed together with Y.

M is a metal (transition metal) selected from Group 4 of the periodic table, such as titanium, zirconium, and hafnium.
Q is a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an anionic ligand, or a neutral ligand capable of coordinating with a lone electron pair. When j is 2 or greater, each Q may be the same or different.
j is an integer of 1 to 4, preferably 2.

Examples of the hydrocarbon group for R ¹ to R ¹⁴ include hydrocarbon groups having 1 to 20 carbon atoms, and specific examples include alkyl groups having 1 to 20 carbon atoms, cycloalkyl groups having 3 to 20 carbon atoms, arylalkyl groups having 7 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, and alkylaryl groups having 7 to 20 carbon atoms.

The substituted hydrocarbon groups (excluding silicon-containing groups) in R ¹ to R ¹⁴ are groups in which some or all of the hydrogen atoms contained in the hydrocarbon group have been substituted with functional groups such as halogen atoms (fluorine, chlorine, bromine, iodine), hydroxyl groups, and amino groups.

Examples of the silicon-containing groups for R ¹ to R ¹⁴ include alkylsilyl groups or arylsilyl groups having 1 to 4 silicon atoms and 3 to 20 carbon atoms, and specific examples thereof include trimethylsilyl, tert-butyldimethylsilyl, and triphenylsilyl.

Adjacent substituents ^R5 to ^R12 on the fluorene ring may be bonded to each other to form a ring. Examples of such substituted fluorenyl groups include benzofluorenyl, dibenzofluorenyl, octahydrodibenzofluorenyl, and octamethyloctahydrodibenzofluorenyl.

For ease of synthesis, the substituents ^R5 to ^R12 on the fluorene ring are preferably symmetrical, i.e., ^R5 = ^R12 , ^R6 = ^R11 , ^R7 = ^R10 , and ^R8 = ^R9 . The fluorene ring moiety is preferably unsubstituted fluorene, 3,6-disubstituted fluorene, 2,7-disubstituted fluorene, or 2,3,6,7-tetrasubstituted fluorene. The 3-, 6-, 2-, and 7-positions on the fluorene ring correspond to ^R7 , ^R10 , ^R6 , and ^R11 , respectively.
It is preferred that R ¹³ and R ¹⁴ each independently represent a hydrogen atom, a hydrocarbon group or a substituted hydrocarbon group.

In the case of general formula (1), ^R13 and ^R14 are bonded to Y to form a substituted methylene group or a substituted silylene group as a bridging moiety. Specific examples of the substituted methylene group and the substituted silylene group include dialkylmethylene, dicycloalkylmethylene, alkylcycloalkylmethylene, alkylarylmethylene, diarylmethylene, dialkylsilylene, dicycloalkylsilylene, alkylcycloalkylsilylene, alkylarylsilylene, diarylsilylene, and halogenated groups thereof.

In the case of general formula (2), Y bonds to the divalent hydrocarbon group A to form a cycloalkylidene group, a cyclomethylenesilylene group, or the like. Specific examples of cycloalkylidene groups and cyclomethylenesilylene groups include cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, bicyclo[3.3.1]nonylidene, norbornylidene, adamantylidene, tetrahydronaphthylidene, dihydroindanylidene, cyclodimethylenesilylene, cyclotrimethylenesilylene, cyclotetramethylenesilylene, cyclopentamethylenesilylene, cyclohexamethylenesilylene, and cycloheptamethylenesilylene.

In Q, examples of halogen atoms include fluorine, chlorine, bromine, and iodine; examples of hydrocarbon groups having 1 to 20 carbon atoms include the same groups as the hydrocarbon groups of R ¹ to R ¹⁴ ; examples of anionic ligands include alkoxy groups, aryloxy groups, carboxylate groups, and sulfonate groups; and examples of neutral ligands capable of coordinating with lone electron pairs include organic phosphorus compounds such as trimethylphosphine, triethylphosphine, triphenylphosphine, and diphenylmethylphosphine, and ethers such as tetrahydrofuran, diethyl ether, dioxane, and 1,2-dimethoxyethane. It is preferable that at least one Q is a halogen atom or an alkyl group having 1 to 20 carbon atoms.

Specific examples of metallocene compound (a) include the compounds exemplified in WO 01/27124, WO 2006/025540, or WO 2007/308607.

The metallocene compound (a) is particularly preferably a compound represented by the following general formula (3), as described in WO 2014/050817, etc.

In general formula (3), R ^1b is a hydrocarbon group, a silicon-containing group, or a halogen-containing hydrocarbon group, R ^2b to R ^12b are selected from a hydrogen atom, a hydrocarbon group, a silicon-containing group, a halogen atom, and a halogen-containing hydrocarbon group, and may be the same or different, and the respective substituents may be bonded to each other to form a ring, M is a transition metal of Group 4 of the periodic table, n is an integer of 1 to 3, Q is the same as Q in general formula (1) or (2), and j is an integer of 1 to 4.

Examples of the hydrocarbon group represented by R ^1b to R ^12b include linear hydrocarbon groups such as linear alkyl groups and linear alkenyl groups; branched hydrocarbon groups such as branched alkyl groups; cyclic saturated hydrocarbon groups such as cycloalkyl groups, norbornyl groups and adamantyl groups; cyclic unsaturated hydrocarbon groups such as aryl groups and cycloalkenyl groups; and groups in which one or more hydrogen atoms of a saturated hydrocarbon group are substituted with a cyclic unsaturated hydrocarbon group, such as an aralkyl group. The hydrocarbon group has usually 1 to 20 carbon atoms, preferably 1 to 15 carbon atoms, and more preferably 1 to 10 carbon atoms.

Examples of the silicon-containing groups in R ^1b to R ^12b include groups represented by the formula --SiR ₃ (wherein the multiple Rs are each independently an alkyl group having 1 to 15 carbon atoms or a phenyl group).

Examples of the halogen-containing hydrocarbon group for R ^1b to R ^12b include groups in which one or more hydrogen atoms of the above hydrocarbon group have been substituted with halogen atoms, such as a trifluoromethyl group.
Examples of the halogen atom in R ^2b to R ^12b include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

In general formula (3), examples of the ring formed by bonding two substituents together (spiro ring, additional ring) include alicyclic rings and aromatic rings. Specific examples include a cyclohexane ring, a benzene ring, a hydrogenated benzene ring, and a cyclopentene ring, with cyclohexane ring, benzene ring, and hydrogenated benzene ring being preferred. Furthermore, such ring structures may further have a substituent such as an alkyl group on the ring.

It is particularly preferable that R ^{1b is a substituent in which the carbon having a free valence (the carbon bonded to the cyclopentadienyl ring) is a tertiary carbon. Specific examples of R 1b include} a tert-butyl group, a tert-pentyl group, a 1-methylcyclohexyl group, and a 1-adamantyl group.
The fluorene ring moiety is not particularly limited as long as it has a structure obtained from a known fluorene derivative, but R ^4b and R ^5b are preferably hydrogen atoms from the viewpoint of molecular weight.

R ^2b , R ^3b , R ^6b , and R ^7b are preferably hydrocarbon groups having 1 to 20 carbon atoms. R ^2b and R ^3b may be bonded to each other to form a ring, and R ^6b and R ^7b may be bonded to each other to form a ring. Examples of such substituted fluorenyl groups include a benzofluorenyl group, a dibenzofluorenyl group, an octahydrodibenzofluorenyl group, a 1,1,4,4,7,7,10,10-octamethyl-2,3,4,7,8,9,10,12-octahydro-1H-dibenzo[b,h]fluorenyl group, a 1,1,3,3,6,6,8,8-octamethyl-2,3,6,7,8,10-hexahydro-1H-dicyclopenta[b,h]fluorenyl group, and a 1',1',3',6',8',8'-hexamethyl-1'H,8'H-dicyclopenta[b,h]fluorenyl group.

R ^8b is preferably a hydrogen atom. R ^9b is preferably an alkyl group having 2 or more carbon atoms. From the viewpoint of synthesis, it is also preferable that R ^10b and R ^11b are hydrogen atoms.
Alternatively, when n=1, it is more preferable that R ^9b and R ^10b are bonded to each other to form a ring, and it is particularly preferable that the ring is a 6-membered ring such as a cyclohexane ring. In this case, it is preferable that R ^11b is a hydrogen atom.
R ^12b is preferably an alkyl group.

M is a transition metal of Group 4 of the periodic table, such as Ti, Zr, or Hf, preferably Zr or Hf, and particularly preferably Zr.

n is an integer of 1 to 3, preferably 1 or 2, and more preferably 1. When n is the above value, it is preferable from the viewpoint of efficiently obtaining the produced polymer.
j is an integer of 1 to 4, preferably 2.

The compound represented by general formula (3) is particularly preferably (8-octamethylfluoren-12'-yl-(2-(adamantan-1-yl)-8-methyl-3,3b,4,5,6,7,7a,8-octahydrocyclopenta[a]indene))zirconium dichloride or (8-(2,3,6,7-tetramethylfluoren)-12'-yl-(2-(adamantan-1-yl)-8-methyl-3,3b,4,5,6,7,7a,8-octahydrocyclopenta[a]indene))zirconium dichloride. Here, the octamethylfluorene refers to 1,1,4,4,7,7,10,10-octamethyl-2,3,4,7,8,9,10,12-octahydro-1H-dibenzo[b,h]fluorene.

<<Carrier (b)>>
The support (b) is preferably in the form of particles, and the metallocene compound (a) is immobilized on the surface and inside of the support (b) to form the metallocene catalyst. A catalyst in this form is generally called a supported metallocene catalyst.
The carrier (b) contains as a main component an organoaluminum compound (b-1), an organoboron compound (b-2), or an inorganic compound (b-3), or a composite of two or more selected from these.

Examples of the organoaluminum compound (b-1) include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, and tri-normal-octylaluminum; dialkylaluminum hydrides such as diisobutylaluminum hydride; tricycloalkylaluminums; and organoaluminum oxy compounds such as aluminoxanes. Other examples of the organoaluminum compound (b-1) include organoaluminum oxy compounds containing boron atoms, halogen-containing aluminoxanes such as those exemplified in WO 2005/066191 and WO 2007/131010, and ionic aluminoxanes such as those exemplified in WO 2003/082879.

Examples of the organic boron compound (b-2) include trialkylammonium tetraarylborate, trialkylammonium tetra(aryl halide)borate, dioctadecylmethylammonium tetraarylborate, dioctadecylmethylammonium tetra(aryl halide)borate, N,N-dialkylanilinium tetraarylborate, and N,N-dialkylanilinium tetra(aryl halide)borate.

Examples of inorganic compounds (b-3) include porous oxides, inorganic halides, clays, clay minerals, and ion-exchange layered compounds. Examples of porous oxides include oxides such as SiO ₂ , Al ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO, BaO, and ThO ₂ , as well as composites or mixtures containing these. Examples of suitable oxides include natural or synthetic zeolites, SiO ₂ -MgO, SiO ₂ -Al ₂ O ₃ , SiO ₂ -TiO ₂ , SiO ₂ -V ₂ O ₅ , SiO ₂ -Cr ₂ O ₃ , and SiO ₂ -TiO ₂ -MgO. Examples of inorganic halides include MgCl ₂ , MgBr ₂ , MnCl ₂ , and MnBr ₂ . The inorganic halides may be used as is, or may be pulverized using a ball mill or a vibration mill. Alternatively, an inorganic halide may be dissolved in a solvent such as alcohol, and then precipitated in the form of fine particles using a precipitating agent.

From the viewpoints of achieving high activity and further suppressing the amount of solvent-soluble matter, support (b) is preferably a support containing aluminum atoms. The content of aluminum atoms in support (b) is preferably 20% by mass or more, more preferably 20 to 60% by mass, even more preferably 30 to 50% by mass, and particularly preferably 35 to 47% by mass.

As such a carrier (b), a solid aluminoxane is preferably used, and the solid aluminoxanes disclosed in, for example, WO 2010/055652, WO 2013/146337, or WO 2014/123212 are particularly preferably used.

"Solid" means that the solid aluminoxane remains substantially solid in the reaction environment in which it is used. More specifically, this refers to the aluminoxane remaining in a solid state under specific temperature and pressure conditions in an inert hydrocarbon medium such as hexane or toluene used in the reaction, for example, when the components constituting the olefin polymerization catalyst are contacted to prepare a solid olefin polymerization catalyst component.

The solid aluminoxane preferably contains an aluminoxane having at least one structural unit selected from structural units represented by the following formula (4) and structural units represented by the following formula (5), more preferably contains an aluminoxane having structural units represented by the following formula (4), and even more preferably contains a polymethylaluminoxane consisting solely of structural units represented by the following formula (4).

In the general formula (4), Me is a methyl group.
In general formula (5), ^R1 is a hydrocarbon group having 2 to 20 carbon atoms, preferably a hydrocarbon group having 2 to 15 carbon atoms, and more preferably a hydrocarbon group having 2 to 10 carbon atoms. Examples of the hydrocarbon group include an alkyl group, a cycloalkyl group, and an aryl group.

The structure of solid aluminoxanes has not necessarily been clarified, but is generally assumed to have a structure in which the structural units represented by formula (4) and/or formula (5) are repeated approximately 2 to 50 times, but is not limited to this structure. The structural units may be bonded in various ways, such as linear, cyclic, or cluster-like, and aluminoxanes are generally assumed to consist of one of these types or a mixture of these. Furthermore, aluminoxanes may consist solely of structural units represented by formula (4) or formula (5).

As the solid aluminoxane, solid polymethylaluminoxane is preferred, and solid polymethylaluminoxane consisting only of the structural unit represented by formula (4) is more preferred.
The solid aluminoxane functions as a catalyst support, and therefore, it is not necessary to use, in addition to the solid aluminoxane, a solid inorganic support such as silica, alumina, silica-alumina, or magnesium chloride, or a solid organic support such as polystyrene beads, as a catalyst support.
Solid aluminoxanes can be prepared, for example, by the methods described in WO 2010/055652 and WO 2014/123212.

《Organic compound component (c)》
The metallocene catalyst may further contain an organic compound component (c) as needed. The organic compound component (c) is used as needed for the purpose of improving the polymerization performance and the physical properties of the resulting polymer. As the organic compound component (c), the above-mentioned organoaluminum compound (b-1) may be used. Other examples include alcohols, phenolic compounds, carboxylic acids, phosphorus compounds, amides, polyethers, and sulfonates.

<Polymerization Conditions>
The polymerization of 4-methyl-1-pentene and, if necessary, ethylene and an α-olefin having 3 to 20 carbon atoms to obtain the 4-methyl-1-pentene copolymer contained in the 4-methyl-1-pentene polymer composition (X) according to the present invention can be carried out by either a liquid phase polymerization method such as solution polymerization or suspension polymerization, or a gas phase polymerization method. In the liquid phase polymerization method, an inert hydrocarbon solvent can be used. Specific examples include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons such as cyclopentane, cyclohexane, methylcyclopentane, and methylcyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as ethylene chloride, chlorobenzene, dichloromethane, trichloromethane, and tetrachloromethane; and mixed solvents of two or more selected from these. Alternatively, the olefin containing 4-methyl-1-pentene itself can be used as the polymerization solvent.

In the above-mentioned polymerization, the method of use and the order of addition of each component can be selected arbitrarily, but the following method can be exemplified. Hereinafter, the metallocene compound (a), the carrier (b), and the organic compound component (c) will also be referred to as "components (a) to (c)," respectively. Furthermore, the organoaluminum compound (b-1), the organoboron compound (b-2), and the inorganic compound (b-3) will also be referred to as "components (b-1) to (b-c)," respectively.
Method (i): A method in which the components (a) and (b) are added to a polymerization reactor in any order.
Method (ii): A method in which a catalyst component in which component (a) is supported on component (b) is added to a polymerization vessel.

In each of the above methods (i) to (ii), component (c) may be further added at any stage, and at least two of the catalyst components may be contacted in advance.
In addition, in the solid catalyst component in which component (a) is supported on component (b), an olefin such as 4-methyl-1-pentene or 3-methyl-1-pentene may be prepolymerized, or a catalyst component may be further supported on the prepolymerized solid catalyst component.

When polymerizing a monomer such as 4-methyl-1-pentene using a metallocene catalyst, the amounts of each component that can make up the metallocene catalyst are as follows. Furthermore, the content of each component in the metallocene catalyst can be adjusted as follows:

Component (a) is used in an amount that is usually ^10-10 to ^10-2 mol, and preferably ^10-8 to ^10-3 mol, per liter of reaction volume. Component (b-1) can be used in an amount that will give a molar ratio of aluminum atoms in component (b-1) to all transition metal atoms (M) in component (a) [Al/M] of usually 10 to 10,000, preferably 30 to 2,000, and particularly preferably 150 to 500. Component (b-2) can be used in an amount that will give a molar ratio of component (b-2) to all transition metal atoms (M) in component (a) [(b-2)/M] of usually 10 to 10,000, preferably 30 to 2,000, and more preferably 150 to 500. Component (b-3) can be used in an amount such that the molar ratio of component (b-3) to the total transition metal atoms (M) in component (a) [(b-3)/M] is usually 10 to 10,000, preferably 30 to 2,000, and more preferably 150 to 500.

When component (c) is used, if component (b) is component (b-1), it can be used in an amount such that the molar ratio of aluminum atoms in component (b-1) to component (c) [Al/(c)] is typically 0.002 to 500, preferably 0.01 to 60; if component (b) is component (b-2), it can be used in an amount such that the molar ratio of component (b-2) to component (c) [(b-2)/(c)] is typically 0.002 to 500, preferably 0.01 to 60; and if component (b) is component (b-3), it can be used in an amount such that the molar ratio of component (b-3) to component (c) [(b-3)/(c)] is typically 0.002 to 500, preferably 0.01 to 60.

The polymerization temperature is usually -50 to 200°C, preferably 0 to 100°C, and more preferably 20 to 100°C. The polymerization pressure is usually between atmospheric pressure and 10 MPa gauge pressure, and preferably between atmospheric pressure and 5 MPa gauge pressure. The polymerization reaction can be carried out batchwise, semi-continuously, or continuously. Hydrogen can be added to the polymerization system to control the molecular weight or polymerization activity of the resulting polymer. The appropriate amount of hydrogen added is approximately 0.001 to 100 NL per kg of olefin.

Multistage polymerization, in which two or more polymerization stages with different reaction conditions are performed, can also be used. For example, by carrying out polymerization in stages under two different conditions, differing in the amount of hydrogen used or the ratio of 4-methyl-1-pentene to ethylene and an α-olefin having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene), it is possible to obtain a polymer with the desired molecular weight distribution or composition distribution.

The 4-methyl-1-pentene polymer according to the present invention can be produced by polymerizing or copolymerizing 4-methyl-1-pentene and, if necessary, a polymerizable monomer such as an α-olefin in the presence of a polymerization catalyst such as the above-mentioned metallocene catalyst.
When the 4-methyl-1-pentene polymer composition (X) according to the present invention is a mixed composition of two kinds of 4-methyl-1-pentene polymers, the first 4-methyl-1-pentene polymer and the second 4-methyl-1-pentene polymer may be produced separately and mixed in a desired blending ratio. Alternatively, the 4-methyl-1-pentene polymer composition (X) may be produced by a multistage polymerization method including, for example, a step (1) of producing a first 4-methyl-1-pentene polymer by slurry polymerization and a step (2) of producing a second 4-methyl-1-pentene polymer by slurry polymerization in the presence of the polymer obtained in the step (1) such that the amount of the second polymer is a desired % by mass when the total amount of the first and second polymers is 100% by mass.

The multi-stage polymerization method has steps (1) and (2) with different polymerization conditions, but it may be a two-stage polymerization consisting of steps (1) and (2), or a three-stage or higher polymerization that includes other steps in addition to steps (1) and (2).

《Process (1)》
In step (1), a first 4-methyl-1-pentene polymer is produced by slurry polymerization. In step (1), the ratio of 4-methyl-1-pentene to at least one monomer selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene), which is used as needed, is set so that the amounts of structural units derived from each monomer are in a desired ratio.

In step (1), a slurry containing a first 4-methyl-1-pentene polymer is obtained. The slurry concentration, i.e., the concentration of the first 4-methyl-1-pentene polymer particles, is typically 0.015 to 45% by mass, and preferably 0.03 to 35% by mass.

《Process (2)》
In step (2), a second 4-methyl-1-pentene copolymer is produced by slurry polymerization in the presence of the first 4-methyl-1-pentene polymer obtained in step (1). In step (2), the feed ratio of 4-methyl-1-pentene to at least one monomer selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene), which is used as needed, is set so that the amounts of structural units derived from each monomer are in a desired ratio.

In step (2), the second 4-methyl-1-pentene polymer is produced so that the amount of the second 4-methyl-1-pentene polymer is the desired mass %, assuming that the total amount of the first 4-methyl-1-pentene polymer obtained in step (1) and the second 4-methyl-1-pentene polymer obtained in step (2) is 100 mass %.

In one embodiment of step (2), 4-methyl-1-pentene and, if necessary, at least one monomer selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) are added to a slurry containing the first 4-methyl-1-pentene polymer, and slurry polymerization of these monomers is carried out.

In step (2), a slurry containing particles containing a first 4-methyl-1-pentene polymer and a second 4-methyl-1-pentene polymer is obtained. The slurry concentration, i.e., the particle concentration, is typically 3 to 50% by mass, and preferably 5 to 40% by mass.

The above multi-stage polymerization method can employ slurry polymerization. "Slurry polymerization" refers to polymerization characterized in that the polymer produced by polymerization is not substantially dissolved in the medium used during polymerization, but exists in the form of, for example, fine particles dispersed in the medium. The above multi-stage polymerization is not limited to slurry polymerization as long as it can produce the 4-methyl-1-pentene polymer composition (X) of the present invention; for example, solution polymerization or gas-phase polymerization can also be used.

《Solid-liquid separation process》
The slurry containing 4-methyl-1-pentene polymer particles containing the first 4-methyl-1-pentene polymer and the second 4-methyl-1-pentene polymer obtained in the step (2) is subjected to solid-liquid separation, for example, filtration, to separate and recover the particles.

Post-processing process
The 4-methyl-1-pentene polymer particles obtained by the multistage polymerization method, for example, the particles obtained by the solid-liquid separation step, may be subjected to known post-treatment steps such as a catalyst deactivation step, a catalyst residue removal step, and a drying step, as necessary, after being produced by the method.
In this manner, a mixture of the first 4-methyl-1-pentene polymer and the second 4-methyl-1-pentene polymer can be obtained.

Additives The polymer composition (X) of the present invention may contain conventionally known additives.
Examples of additives include secondary antioxidants, heat stabilizers, weather stabilizers, antistatic agents, slip agents, antiblocking agents, antifogging agents, lubricants, dyes, pigments, natural oils, synthetic oils, waxes, fillers, and hydrochloric acid absorbers. The content of the additives is not particularly limited, but is usually 0 to 50 parts by mass, and preferably 0 to 10 parts by mass, for each additive, relative to 100 parts by mass of the polymer component including copolymers (A) and (B) and the like.
The 4-methyl-1-pentene polymer composition (X) of the present invention may contain one or more additives.

Properties of 4-methyl-1-pentene polymer composition (X) The 4-methyl-1-pentene polymer composition (X) according to the present invention has the same physical properties as conventional 4-methyl-1-pentene polymers, such as excellent heat resistance, transparency, light weight, mold releasability, and stain resistance, and yet has a longer half-crystallization time and stretchability than conventional polymer compositions containing a 4-methyl-1-pentene polymer. Furthermore, the 4-methyl-1-pentene polymer composition (X) according to the present invention has a specific melting point and can be subjected to laminate inflation molding at a relatively low temperature.

The 4-methyl-1-pentene polymer composition (X) according to the present invention contains one or more 4-methyl-1-pentene polymers and satisfies the following requirements (X-1) to (X-4). It is also preferable that the 4-methyl-1-pentene polymer composition (X) further satisfies one or more of the following requirements (X-5) to (X-8).

Requirement (X-1): The density measured in accordance with JIS K7112 (density gradient tube method) is 0.82 to 0.88 g/m ³ .
The density is preferably 0.82 to 0.86 g/m ³ , and more preferably 0.82 to 0.84 g/m ³ .
When the density of the 4-methyl-1-pentene polymer composition (X) is within the above range, a lightweight film can be obtained.

Requirement (X-2): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 190°C to 220°C.
The melting point (Tm) is preferably 190°C to 215°C, more preferably 190°C to 210°C.
The melting point (Tm) of the 4-methyl-1-pentene polymer composition (X) according to the present invention is relatively low compared to the melting point (Tm) of a general 4-methyl-1-pentene polymer, which is about 220 to 250°C, and satisfies the above-mentioned range.
The 4-methyl-1-pentene polymer composition (X) having a melting point (Tm) that satisfies the above-mentioned relatively low specific range can be molded under the same conditions as those for the thermoplastic resin (Y) described below, and can be suitably subjected to laminate inflation molding with the thermoplastic resin (Y). It can also form a layer that has excellent adhesion to a layer containing the thermoplastic resin (Y).

Requirement (X-3): The enthalpy of fusion ΔH is less than 35 J/g.
The fusion enthalpy ΔH is a value measured in accordance with JIS K7122 using the 4-methyl-1-pentene polymer composition (X).
The fusion enthalpy ΔH is preferably 5 J/g or more and less than 35 J/g, and more preferably 8 to 32 J/g.
When the melting enthalpy ΔH of the 4-methyl-1-pentene polymer composition (X) is within the above range, moldability is improved, and laminate inflation molding with the thermoplastic resin (Y) described below can be suitably carried out.

Requirement (X-4): The crystallization half time (Tc1/2) at 215°C measured by DSC using the following measurement method is 220 seconds or more, or cannot be measured.
Method for measuring crystallization half time (Tc1/2): Using a DSC8500 manufactured by PerkinElmer Co., Ltd., the temperature is increased from 30°C to 280°C at a heating rate of 500°C/min, the temperature is maintained for 10 minutes, and then the temperature is decreased to 215°C at a cooling rate of 500°C/min, and the crystallization half time at 215°C is measured.
The crystallization half time is preferably 500 seconds or more or not measured, more preferably 800 seconds or more or not measured, even more preferably 1000 seconds or more or not measured, even more preferably 1500 seconds or more or not measured, and particularly preferably 2000 seconds or more or not measured.
When the crystallization half time of the 4-methyl-1-pentene polymer composition (X) satisfies the above condition, the crystallization rate during melt molding is slowed down, stretchability is improved, and laminate inflation molding involving stretching can be suitably performed.

Requirement (X-5): The content of structural units derived from 4-methyl-1-pentene is 90.0 mol% or more and less than 100 mol%, and the content of structural units derived from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is more than 0 mol% and 10.0 mol% or less.
The content of structural units derived from 4-methyl-1-pentene is preferably 91.0 to 99.5 mol %, more preferably 92.0 to 99.0 mol %. The content of structural units derived from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is preferably 0.5 to 9.0 mol %, more preferably 1.0 to 8.0 mol %.
When the content of the structural units of the 4-methyl-1-pentene polymer composition (X) satisfies the above conditions, the X layer of the laminate can have excellent heat resistance, transparency, and releasability.

Requirement (X-6): The intrinsic viscosity [η] measured in decalin at 135° C. is 0.5 to 8.0 dl/g. Specifically, this can be measured, for example, by the measurement method described in the Examples below.
The intrinsic viscosity [η] is preferably 0.8 to 7.0 dL/g, more preferably 0.9 to 6.0 dL/g, even more preferably 1.0 to 5.0 dL/g, still more preferably 1.1 to 4.0 dL/g, and particularly preferably 1.2 to 4.0 dL/g.
The 4-methyl-1-pentene polymer composition (X) has an intrinsic viscosity that satisfies the above range, and therefore has good moldability, and can be suitably subjected to laminate inflation molding accompanied by stretching.

Requirement (X-7): The melt tension (MT) measured at 260°C is 25 mN or more.
The melt tension is preferably 26 mN or more, more preferably 26 to 100 mN, and even more preferably 27 to 50 mN. The melt tension can be adjusted, for example, by controlling the molecular weight of the polymer.
When the 4-methyl-1-pentene polymer composition (X) has a relatively high melt tension that satisfies the above range, the stretchability is improved, and laminate inflation molding accompanied by stretching can be suitably carried out.

Requirements (X-8)
The endothermic end temperature (TmE) in the exothermic/endothermic curve (melting (endothermic) curve) measured with a differential scanning calorimeter (DSC) by the method described in the Examples below is preferably 230° C. or lower, more preferably 228° C. or lower, even more preferably 225° C. or lower, and even more preferably 220° C. or lower. Here, the endothermic end temperature means the temperature at which melting is completed, and is an index different from the onset and offset, which are generally the intersection points between the baseline and the tangent to the steady-state line.
The endothermic end temperature can be adjusted to a desired value by, for example, appropriately selecting an olefin polymerization catalyst when polymerizing the 4-methyl-1-pentene polymer, or by controlling the content ratio of the structural units.
The 4-methyl-1-pentene polymer composition (X) having an endothermic end temperature within the above range has excellent heat resistance. Therefore, the X layer containing the 4-methyl-1-pentene polymer composition (X) having an endothermic end temperature within the above range also tends to have excellent heat resistance.

The 4-methyl-1-pentene polymer composition (X) according to the present invention satisfies the above-mentioned requirements (X-1) to (X-4), and preferably further satisfies one or more of requirements (X-5) to (X-8). Preferred embodiments include those that satisfy requirements (X-1) to (X-6), those that satisfy requirements (X-1) to (X-4) and requirement (X-7), those that satisfy all of requirements (X-1) to (X-7), and those that satisfy all of requirements (X-1) to (X-8).

<Thermoplastic resin (Y)>
As the thermoplastic resin (Y), any known thermoplastic resin other than a 4-methyl-1-pentene polymer can be used without particular limitation, and examples thereof include olefin polymers, polyamides, polyesters, polyacetals, styrene resins, acrylic resins, polycarbonates, polyphenylene oxides, chlorine-based resins, vinyl acetate resins, ethylene-(meth)acrylic acid ester copolymers, ethylene-(meth)acrylic acid resins and ionomer resins thereof, vinyl alcohol resins, cellulose resins, thermoplastic elastomers, various copolymer rubbers, etc. In the present invention, the thermoplastic resin (Y) is preferably a resin that can be molded at a temperature of less than 250°C, and more preferably has a melting point (Tm) of 210°C or lower.

The thermoplastic resin (Y) is preferably a polyolefin polymer, and examples thereof include polyethylene, polypropylene, poly-1-butene, polymethylbutene, and ethylene-α-olefin-non-conjugated polyene copolymers.
In the present invention, among these, it is particularly preferable that the thermoplastic resin (Y) is polyethylene or polypropylene.

Polyethylene includes ethylene homopolymers and copolymers of monomers primarily composed of ethylene. As copolymers of monomers primarily composed of ethylene, copolymers of ethylene and α-olefins having 3 to 12 carbon atoms are preferred. Examples of α-olefins having 3 to 12 carbon atoms include linear or branched α-olefins such as propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, and 1-dodecene. Specific examples of polyethylene include ultra-high molecular weight polyethylene, high-density polyethylene, medium-density polyethylene, low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and the like.

Examples of polypropylene include propylene homopolymers and copolymers of monomers containing propylene as the main component. As a copolymer of a monomer containing propylene as the main component, a copolymer of propylene with ethylene and an α-olefin having 4 to 12 carbon atoms is preferred. Examples of α-olefins having 4 to 12 carbon atoms include linear or branched α-olefins such as 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, and 1-dodecene.

The monomer other than ethylene that constitutes polyethylene, or the monomer other than propylene that constitutes polypropylene, may be one type alone or two or more types, and may contain a copolymerizable monomer other than an α-olefin.

<Laminate>
The laminate of the present invention is a laminate including an X layer containing the 4-methyl-1-pentene polymer composition (X) and a Y layer containing the thermoplastic resin (Y). The laminate of the present invention is not particularly limited as long as it has one or more X layers and one or more Y layers, and examples of the layer configuration include X layer/Y layer, X layer/X layer/Y layer, X layer/Y layer/X layer, X layer/Y layer/Y layer, Y layer/X layer/Y layer, and X layer/Y layer/X layer/Y layer.

When the laminate includes two or more X layers, the X layers may contain the same 4-methyl-1-pentene polymer composition (X) or different 4-methyl-1-pentene polymer compositions (X). When the laminate includes two or more Y layers, the Y layers may contain the same thermoplastic resin (Y) or different thermoplastic resins (Y).

The laminate of the present invention is not limited to any particular shape, but is preferably a sheet- or film-like laminate. The thickness of the laminate is not particularly limited, but is preferably 0.1 to 100 μm, more preferably 1 to 50 μm. Laminates of this thickness are preferred because they can be suitably manufactured by laminate inflation molding, which involves stretching. The thicknesses of the layers constituting the laminate may be the same or different.

The laminate of the present invention can be made to have little variation in thickness and excellent thickness precision. Preferably, the laminate of the present invention has a thickness precision of 32 or less, more preferably 30 or less, even more preferably 25 or less, and particularly preferably 20 or less, calculated by taking the average thickness (a) obtained by measuring at sufficient measurement points and the standard deviation (σ) of the thickness variation, and calculating 2σ ÷ a × 100 (%). The average thickness (a) and standard deviation (σ) will vary depending on factors such as the size of the film, but can be determined, for example, from thickness measurements taken at 50 evenly spaced points, as shown in the examples described below.

The laminate of the present invention may be any laminate containing a layer of the 4-methyl-1-pentene polymer composition (X) and a layer of the thermoplastic resin (Y), and can be produced by a conventional laminate molding method. However, because the 4-methyl-1-pentene polymer composition (X) of the present invention has excellent stretchability and a relatively low melting point, it can be suitably produced by a laminate inflation molding method with the thermoplastic resin (Y), which provides excellent bubble stability during laminate inflation molding and allows for stable molding. When the laminate of the present invention is produced by an inflation molding method, it is preferred because it results in little variation in film thickness and excellent film thickness precision. Furthermore, the laminate inflation molding method is preferred because it is easy to obtain a film with a uniform film thickness throughout, does not require removal of uneven portions, and provides excellent production yields.

In addition, the laminate of the present invention contains the 4-methyl-1-pentene polymer composition (X), thereby exhibiting excellent heat resistance and other properties, and when an X layer is present on the surface, it also exhibits excellent releasability.

The laminate of the present invention can be suitably used as a material for, for example, packaging materials for daily necessities, food packaging materials, food containers, retort pouch containers, protective films, decorative films/sheets, shrink films, infusion bags, heat-sealing films, medical containers, and release films, and is particularly suitable for use in packaging.

Manufacturing Method of Laminate The laminate of the present invention may be obtained by any method, but is preferably obtained by the manufacturing method of the laminate of the present invention.
The method for producing a laminate of the present invention includes a step of subjecting the above-mentioned 4-methyl-1-pentene polymer composition (X) and the thermoplastic resin (Y) to laminate inflation molding.
The laminate inflation molding is preferably carried out by using an inflation molding apparatus capable of laminate (multi-layer) molding and co-extruding a plurality of resins constituting each layer from an inflation die.

The laminate inflation molding process is performed at a molding temperature of less than 250°C. Here, "molding temperature" refers to the temperature at the time of molding, typically the die temperature. The molding temperature in laminate inflation molding is preferably less than 250°C and equal to or higher than the melting points of the 4-methyl-1-pentene polymer composition (X) and the thermoplastic resin (Y). While this temperature varies depending on the 4-methyl-1-pentene polymer composition (X) and the thermoplastic resin (Y) used, it is preferably in the range of 180°C or higher but lower than 250°C, more preferably 190°C or higher but lower than 250°C, and even more preferably 200 to 245°C. In the present invention, the melting point (Tm) of the 4-methyl-1-pentene polymer composition (X) used is lower than that of typical 4-methyl-1-pentene polymers, and the semi-crystallization time is long. Furthermore, the composition preferably also has a high melt tension, which allows for good stretchability and enables laminate inflation molding with a thermoplastic resin (Y) that generally has a lower melting point than the 4-methyl-1-pentene polymer.

While there are no particular limitations on the co-extrusion method used in laminate inflation molding, it is preferable to perform co-extrusion in an upward direction opposite to the direction of gravity.

In the manufacturing method of the present invention, laminate inflation molding is performed under conditions where the expansion ratio (bubble ratio) exceeds 1.0. Here, the expansion ratio (bubble ratio) refers to the ratio of the maximum bubble diameter to the die diameter, and if it exceeds 1.0, the resins of each co-extruded layer will be stretched. It is desirable to perform laminate inflation molding under conditions where the expansion ratio (bubble ratio) is preferably 1.1 to 5.0, more preferably 1.2 to 4.5, even more preferably 1.5 to 4.0, and even more preferably 1.8 to 3.0. In the present invention, since the 4-methyl-1-pentene polymer composition (X) satisfies the above-mentioned requirements, a laminate with excellent stretchability and good thickness precision (thickness/thinness precision) can be obtained, even in laminate inflation molding involving stretching where the expansion ratio (bubble ratio) exceeds 1.0.

In the laminate inflation molding process, the take-up speed of the laminate inflation film, which is the laminate, is typically 2 to 40 m/min, and preferably 5 to 30 m/min. The thickness of the laminate obtained by the method of the present invention is not particularly limited, but is preferably 0.1 to 100 μm, and more preferably 1 to 50 μm. The thickness of each layer constituting the laminate may be the same or different.

The laminate of the present invention can be suitably used as a material for, for example, packaging materials for daily necessities, food packaging materials, food containers, retort pouch containers, protective films, decorative films/sheets, shrink films, infusion bags, heat-sealable films, medical containers, and release films.

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

In the following, the physical properties were measured or evaluated using the following methods.

<Content of structural units derived from ethylene or α-olefins (excluding 4-methyl-1-pentene)>
The content of structural units derived from 4-methyl-1-pentene and the content of ethylene or α-olefins (excluding 4-methyl-1-pentene) in the polymer composition (or each polymer) were calculated from the results of measurement by ¹³ C-NMR using the following apparatus and conditions.

Measurements were performed using a JEOL ECP500 nuclear magnetic resonance spectrometer using a mixed solvent of ortho-dichlorobenzene and heavy benzene (80/20% by volume), a sample concentration of 55 mg/0.6 mL, a measurement temperature of 120°C, an observation nucleus of C (125 MHz), a sequence of ^single pulse proton decoupling, a pulse width of 4.7 μsec (45° pulse), a repetition time of 5.5 seconds, an accumulation count of 10,000 or more, and a chemical shift reference value of ^27.50 ppm. From the obtained C-NMR spectrum, the content of structural units derived from 4-methyl-1-pentene and the content of structural units derived from ethylene or α-olefins (excluding 4-methyl-1-pentene) were quantified.

<Intrinsic viscosity [η]>
The intrinsic viscosity [η] of the polymer or polymer composition was measured at 135 ° C. using decalin solvent. That is, about 20 mg of polymer powder, pellets, or resin mass was dissolved in 15 mL of decalin, and the specific viscosity ηsp was measured in an oil bath at 135 ° C. After diluting this decalin solution with 5 mL of decalin solvent, the specific viscosity ηsp was measured in the same manner. This dilution procedure was repeated two more times, and the value of ηsp/C when the concentration (C) was extrapolated to 0 was determined as the intrinsic viscosity (see the formula below).
[η]=lim(ηsp/C) (C→0)

<Density>
The density was measured in accordance with JIS K7112 (density gradient tube method).

<Melting point (Tm) and enthalpy of fusion (ΔH)>
An exothermic/endothermic curve was obtained using a DSC measuring device (DSC220C) manufactured by Seiko Instruments Inc. The temperature at the melting peak position during temperature rise was taken as the melting point (Tm). The melting peak area at the melting peak was taken as the melting enthalpy (ΔH).
Calorimetry was performed as follows: Approximately 5 mg of sample was cut out from a 0.5 mm thick injection test piece, placed in an aluminum pan for measurement, heated from 20°C to 280°C at a heating rate of 10°C/min, held at 280°C for 5 minutes, cooled to 20°C at a cooling rate of 10°C/min, held at 20°C for 5 minutes, then heated again from 20°C to 280°C at a heating rate of 10°C/min, and cooled again to 50°C at a cooling rate of 50°C/min. The melting peak that appeared during the second heating was taken as the melting point (Tm).
When there were multiple melting peaks, the higher peak temperature was taken as the melting point (Tm), and the peak area at the higher melting point was taken as the melting enthalpy (ΔH).

<Crystallization half time (Tc1/2)>
The exothermic/endothermic curve was measured using a DSC measuring device (DSC8500) manufactured by PerkinElmer Co., Ltd., and the time required for the peak area at 215°C to reach half its original value was defined as the half-crystallization time (Tc1/2). The measurement was performed as follows: Approximately 5 mg of sample was cut out from a 0.5 mm thick injection test piece, placed in an aluminum pan for measurement, heated from 30°C to 280°C at a heating rate of 500°C/min, held at 280°C for 10 minutes, and then cooled to 215°C at a cooling rate of 500°C/min, and then measured.

<Endothermic end temperature (TmE)>
The temperature at which the endotherm of the exothermic/endothermic curve (melting (endothermic) curve) ends was defined as the endothermic temperature (TmE). The end point is the point at which it can be confirmed that the curve deviates from the baseline at which the calorific value becomes constant at the end of the endotherm, and that a difference in the calorific value begins to appear.

<Melt tension>
A Capillograph 1D device manufactured by Toyo Seiki Seisakusho, Ltd. was used. A sample was placed in a melting furnace (diameter 9.55 mm) set at 260°C and fully melted, and then passed through a capillary with an L/D of 8/2.095 mm and an inlet angle of 180° at an extrusion speed of 15 mm/min, and then passed through a pulley fixed at a position 58 cm from the bottom of the capillary. The stress applied to the pulley when the molten resin was wound up at a speed of 15 m/min was measured, and this stress was taken up as the melt tension.

<Bubble stability>
The bubble stability during inflation molding was evaluated according to the following criteria.
⊚: Bubbles were stable for a long time, and a good film was obtained.
◯: Slight movement occurred in the bubble, but stable molding was possible.
x: Bubbles fluctuated up and down, causing fluctuations in film width, or molding was not possible.

<Eye discharge evaluation>
When a black or brown resin deterioration deposit is observed near the extrusion die lip during continuous film production, it is called the eye discharge phenomenon. When this deposit is observed during 30 minutes of continuous film production, it is evaluated as ×, and when it is not observed, it is evaluated as ○.

<Laminate thickness and thickness accuracy>
The thickness was measured at 50 points at 1 cm intervals using a thickness measuring dial gauge, and the average value was calculated. The standard deviation (σ) of the measured thickness was doubled (2σ) by the average value, and the resulting value expressed as a percentage (×100) was used as the thickness accuracy.
The value was evaluated as follows: ◯ if it was less than 25, Δ if it was 25 or more but 32 or less, and x if it was more than 32.

<Fisheye evaluation>
In particular, when a crosslinked resin such as polyethylene is continuously formed into a film, if the molding temperature is too high, gel may be generated inside and outside the cylinder, and these may be observed as fish eyes in the film. When film was continuously formed for 30 minutes, if this was observed, it was evaluated as ×, and if not, it was evaluated as ○.

<Surface tension>
According to JIS K6768, several drops of the wetting reagent mixture were dropped onto the laminate, and the test mixture was immediately spread using a cotton swab. If the state of the central part of the liquid film after 2 seconds had passed was not broken and maintained its original state, it was judged as "wet," and if it was broken, it was judged as "not wet." The surface tension (mN/m) was recorded when the mixture composition was switched from a non-wetting mixture composition to a mixture composition judged to just wet the laminate.
The surface tension is an index of releasability.

[Production of Polymer Compositions X-1 to X-4]
A 4-methyl-1-pentene copolymer was obtained in accordance with the polymerization method described in Comparative Example 1 (paragraph [0158]) of WO 2017/150265, except that the α-olefin was changed to an α-olefin shown in Table 1, and the proportions of 4-methyl-1-pentene, the α-olefin, and hydrogen used were changed so that the physical properties of the resulting copolymer would be the values shown in Table 1.
To this copolymer, 0.5 parts by mass of n-octadecyl-3-(4'-hydroxy-3',5'-di-t-butylphenyl)propionate was blended as a heat stabilizer. The resulting mixture was then granulated using a twin-screw extruder BT-30 (screw diameter 30 mm, L/D = 46) manufactured by Plastics Technology Research Institute Co., Ltd., at a set temperature of 270°C, a resin extrusion rate of 60 g/min, and 200 rpm, to obtain pellets of polymer compositions X-1 to X-4, respectively. The physical properties are shown in Table 1.

[Production of Polymer Composition X-5]
Pellets of polymer composition X-5 were obtained in the same manner as in the production of polymer compositions X-1 to X-4, except that the proportions of 4-methyl-1-pentene, other α-olefins (a mass mixture of 1-hexadecene, 1-octadecene, etc.), and hydrogen were changed in accordance with the polymerization method described in Comparative Example 9 of WO 2006/054613. The physical properties are shown in Table 1.

[Example 1]
Two-kind, two-layer, top-blowing, air-cooled inflation molding was carried out using an inflation molding machine with a ring die diameter of 300 mmφ and a lip opening of 1.0 mmφ, using two 20 mmφ extruders.
Inside the ring die (inner layer during inflation molding), LLDPE (Evolue (registered trademark) SP3010 manufactured by Prime Polymer) was used as the polyethylene, and extrusion was performed at an extruder temperature of 200°C and a die temperature of 240°C.
The polymer composition X-1 obtained above was used on the outside of the ring die (outer layer of the molded article during inflation molding) and extruded at an extruder temperature of 245°C and a die temperature of 240°C.
The bubble diameter was adjusted to 600 mmφ relative to the ring die diameter, i.e., the expansion ratio (bubble ratio) was adjusted to 2.0, and the film thicknesses of the inner and outer layers were adjusted to 20 μm and 10 μm, respectively, to form a laminate. The evaluation results of the obtained laminate are shown in Table 2.

[Examples 2 to 4]
Except for changing the polymer compositions used to the polymer compositions X-2 to X-4 obtained above, laminate films were produced in the same manner as in Example 1. The evaluation results of the obtained laminates are shown in Table 2.

[Example 5]
Except for changing the polyethylene used to HDPE (Hi-Zex (registered trademark) 3300F manufactured by Prime Polymer), a laminate film was produced in the same manner as in Example 1. The evaluation results of the obtained laminate are shown in Table 2.

[Example 6]
A laminate film was produced in the same manner as in Example 1, except that the polyethylene used was changed to homopolypropylene (F113G manufactured by Prime Polymer) and the extruder temperature was changed to 230° C. The evaluation results of the obtained laminate are shown in Table 2.

In Examples 1 to 6, the bubbles remained stable for a long period of time, resulting in a good laminate. Furthermore, even after long periods of continuous molding, no eye discharge was observed near the die lip, and no fisheyes were observed in the laminate.

[Example 7]
Two-type, three-layer, top-blown, air-cooled inflation molding was performed.
Polymer composition X-1 was used for the inner and outer layers, and extruded using two extruders with a diameter of 20 mm at an extruder temperature of 245°C and a die temperature of 240°C.
The intermediate layer was made of polyethylene LLDPE (Evolue (registered trademark) SP3010 manufactured by Prime Polymer) and extruded using a 25 mmφ extruder at an extruder temperature of 200°C and a die temperature of 240°C.
The film thickness of the inner and outer layers was adjusted to 7.5 μm, and that of the intermediate layer was adjusted to 15 μm. Except for this, a laminate was produced in the same manner as in Example 1. The evaluation results of the obtained laminate are shown in Table 2.

In Example 7, slight movement of the bubble occurred, but stable molding was possible. However, when molding was continued for an extended period of time, black eye discharge, which appeared to be a deteriorated substance, appeared near the die lip, and the occurrence of fisheyes in the laminate was confirmed.

[Example 8]
A laminate film was produced in the same manner as in Example 1, except that the extruder temperature of the polymer composition used on the outside of the ring die (the outer layer of the molded product during inflation molding) and the die temperature were set to 260° C. The evaluation results of the obtained laminate are shown in Table 2.

[Comparative Example 1]
An attempt was made to form a laminate film in the same manner as in Example 1, except that the polymer composition used was changed to the polymer composition X-5 obtained above, but film formation was not possible.
In Comparative Example 1, the pressure inside the extruder rose abnormally, making molding impossible. This is presumably because the melting temperature was low, resulting in insufficient melting of polymer composition X-5.

[Comparative Example 2]
A laminate was produced in the same manner as in Example 1, except that the polymer composition used was changed to the polymer composition X-5 obtained above, and the extruder temperature and the die temperature were set to 260° C. The evaluation results of the obtained laminate are shown in Table 2.

In Comparative Example 2, slight movement occurred in the bubble, but stable molding was possible. Thickness precision was poor. Furthermore, after long periods of continuous molding, black eye discharge, which appeared to be a deteriorated substance, appeared near the die lip, and the occurrence of fisheyes in the laminate was confirmed.

Claims (8)

an X layer containing a 4-methyl-1-pentene polymer composition (X) that satisfies the following requirements (X-1) to (X-4);
and a Y layer containing a thermoplastic resin (Y).
Requirement (X-1): The density measured in accordance with JIS K7112 (density gradient tube method) is 0.82 to 0.88 g/m ³ .
Requirement (X-2): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 190°C to 220°C.
Requirement (X-3): The enthalpy of fusion ΔH is less than 35 J/g.
Requirement (X-4): The crystallization half time at 215°C measured by DSC using the following measurement method is 220 seconds or more, or cannot be measured.
Method for measuring the crystallization half time: Using a DSC8500 manufactured by PerkinElmer Co., Ltd., the temperature is increased from 30°C to 280°C at a heating rate of 500°C/min, the temperature is maintained for 10 minutes, and then the temperature is decreased to 215°C at a cooling rate of 500°C/min, and the crystallization half time at 215°C is measured. The laminate according to claim 1, wherein the 4-methyl-1-pentene polymer composition (X) satisfies the following requirements (X-5) and (X-6):
Requirement (X-5): The content of structural units derived from 4-methyl-1-pentene is 90.0 mol% or more and less than 100 mol%, and the content of structural units derived from ethylene and α-olefins having 3 to 20 carbon atoms (excluding 4-methyl-1-pentene) is more than 0 mol% and 10.0 mol% or less.
Requirement (X-6): The intrinsic viscosity [η] measured in decalin at 135° C. is 0.5 to 8.0 dl/g. The laminate according to claim 1 or 2, wherein the 4-methyl-1-pentene polymer composition (X) satisfies the following requirement (X-7):
Requirement (X-7): The melt tension (MT) measured at 260°C is 25 mN or more. The laminate according to any one of claims 1 to 3, wherein the thermoplastic resin (Y) is polyethylene or polypropylene. The laminate described in any one of claims 1 to 4 has a thickness of 0.1 to 100 μm. The laminate according to any one of claims 1 to 5, which is an inflation film. The laminate according to any one of claims 1 to 6, which is used for packaging. A method for producing a laminate, comprising a step of subjecting a 4-methyl-1-pentene polymer composition (X) that satisfies the following requirements (X-1) to (X-4) and a thermoplastic resin (Y) to laminate inflation molding under conditions such that the expansion ratio (bubble ratio) exceeds 1.0 and the molding temperature is lower than 250°C:
Requirement (X-1): The density measured in accordance with JIS K7112 (density gradient tube method) is 0.82 to 0.88 g/m ³ .
Requirement (X-2): The melting point (Tm) measured by differential scanning calorimetry (DSC) is 190°C to 220°C.
Requirement (X-3): The enthalpy of fusion ΔH is less than 35 J/g.
Requirement (X-4): The crystallization half time at 215°C measured by DSC using the following measurement method is 220 seconds or more, or cannot be measured.
Method for measuring the crystallization half time: Using a DSC8500 manufactured by PerkinElmer Co., Ltd., the temperature is increased from 30°C to 280°C at a heating rate of 500°C/min, the temperature is maintained for 10 minutes, and then the temperature is decreased to 215°C at a cooling rate of 500°C/min, and the crystallization half time at 215°C is measured.