JP2005053131A - Laminate and medical bag using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical bag having high sanitation properties, excellent in flexibility, transparency, glossiness and interlaminar strength after sterilization treatment at 121°C, excellent in heat resistance and falling bag strength at the times of transport and handling, having good pinhole resistance and housing a liquid medicine, blood or the like. <P>SOLUTION: This laminate is obtained by laminating a propylene resin layer, which is based on a component (A) being a propylene/α-olefin random copolymer having specific physical properties polymerized using a metallocene catalyst, on one side or both sides of an ethylenic resin layer comprising 60-97 wt.% of a component (B) which is an ethylene/3-12Cα-olefin copolymer having specific physical properties and 3-40 wt.% of a component (C) being high density polyethylene having specific physical properties. The medical bag can be preferably used as a soft container in particular in a medical field such as an infusion bag or the like or a food packaging bag for a retort requiring heat resistance of 121°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a medical bag for storing a medical solution, blood and the like, which is excellent in hygiene, flexibility, transparency, heat resistance, pinhole resistance, glossiness, delamination strength, and the like.

  Currently, a soft bag made of polyvinyl chloride containing a plasticizer is known as a medical container. Soft bags do not require the introduction of air as in the case of glass or other hard containers, and have advantages such as the safety of the bag itself being squeezed by the atmospheric pressure when the contents are dropped, and the convenience of transportation is high. . However, since the plasticizer and residual monomer contained in the polyvinyl chloride are precipitated as fine particles in the content liquid, there is a problem. Therefore, an alternative material is desired.

  On the other hand, a medical bag using a polymer such as an ethylene-vinyl acetate copolymer and an elastomer as an intermediate layer has been proposed in terms of flexibility, transparency, hygiene, and the like (see Patent Document 1). However, these polymers used for the intermediate layer have a defect that the appearance is inferior, for example, wrinkles are generated during sterilization due to poor heat resistance, or transparency after sterilization is reduced. In addition, pinholes may occur during transportation.

  Also known is a laminate in which the outer layer is a polypropylene resin and the intermediate layer is a conventional linear ethylene / α-olefin copolymer (see Patent Document 2). In addition, a laminate has been proposed in which an outer layer is made of a polypropylene resin and an intermediate layer is made of a metallocene catalyst, and an ethylene / α-olefin copolymer having a single melting point (see Patent Document 3). However, medical bags made of these laminates do not have a high level of transparency, strength, flexibility and heat resistance.

  Furthermore, there has been proposed a medical container (see Patent Document 4) that is formed of a sheet that is produced with a metallocene-based catalyst and that includes polypropylene having a melting point of 140 ° C. or less as a forming layer (see Patent Document 4). There was a problem that the falling bag strength was not sufficient. A laminate sheet in which another polymer layer is combined with the polypropylene-forming layer is also described, but it has not yet solved the problem of insufficient bag drop strength.

  Further, in the laminate including at least the outer layer, the intermediate layer, and the inner layer in this order, the outer layer is made of a polypropylene resin, and the intermediate layer includes ethylene containing a low crystalline component and a high crystalline component, and α having 3 to 18 carbon atoms. -The laminated body which consists of a copolymer with an olefin is proposed (refer patent document 5). However, after high-pressure steam sterilization treatment, there was a problem that transparency, bag drop strength, glossiness and delamination strength were not yet sufficient.

Therefore, there is no problem as described above, that is, not only good hygiene, but also excellent flexibility and transparency, high heat resistance, glossiness and delamination strength, and further in a low temperature atmosphere Also, a medical bag having a good bag breaking strength at the time of dropping has not been achieved by a conventional multilayer medical bag.
JP 58-165866 A JP-A-6-171039 JP-A-9-141793 JP-A-9-99036 JP 2000-343660 A

  It is an object of the present invention to provide a medical bag containing medical fluid, blood, etc. that has high hygiene, excellent flexibility, transparency, glossiness and delamination strength, and good pinhole resistance. To do.

  As a result of intensive studies to solve the above problems, the present inventors have laminated the specific propylene / α-olefin random copolymer and the specific ethylene / α-olefin copolymer, thereby obtaining the above-mentioned invention. Obtaining knowledge that the object can be achieved, the present invention has been completed.

That is, in the first invention of the present invention, the following component (A) is added to one or both sides of an ethylene resin layer comprising 60 to 97% by weight of the following component (B) and 3 to 40% by weight of the following component (C). It exists in the laminated body characterized by laminating | stacking the propylene-type resin layer which is a main component.
Component (A): Propylene / α-olefin random copolymer (A1) melt flow rate (MFR: 230 ° C., 21.18 N) polymerized using a metallocene catalyst and having the following properties (A1) to (A3) Load) is 1 to 20 g / 10 minutes.
(A2) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 1.5 to 3.5.
(A3) Melting peak temperature (Tm) by 121-150 degreeC by a differential thermal scanning calorimeter (DSC).
Component (B): Copolymer of ethylene and α-olefin having 3 to 12 carbon atoms having the following characteristics (B1) to (B2) (B1) Melt flow rate (MFR: 190 ° C., 21.18 N load) Is 0.1 to 20 g / 10 min.
(B2) The density is 0.880 to 0.930 g / cm ³ .
Component (C): High density polyethylene (C1) melt flow rate (MFR: 190 ° C., 21.18 N load) having the following characteristics (C1) to (C2) is 0.1 to 50 g / 10 min.
(C2) Density is 0.940-0.980 g / cm ³ .

Further, according to a second aspect of the present invention, the component (B) is produced using a metallocene catalyst and has the following characteristics (B3) to (B4): Exists in the body.
(B3) The content of α-olefin is 5 to 40% by weight.
(B4) The ratio (Mz / Mn) of the Z average molecular weight (Mz) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 8.0 or less.

The third aspect of the present invention resides in the laminate according to claim 1 or 2, wherein the component (A) has the following property (A4).
(A4) The relationship between the melting peak temperature (Tm) and the comonomer content (Ec) satisfies the following formula (1).

Tm ≧ −6.7049 × Ec + 140 (1)
The fourth aspect of the present invention resides in the laminate according to any one of claims 1 to 3, wherein the component (A) is a propylene / ethylene random copolymer.

  Moreover, 5th invention of this invention exists in the laminated body of any one of Claims 1-4 by which a propylene-type resin layer is laminated | stacked on both sides of an ethylene-type resin layer.

  Moreover, 6th invention of this invention is a composition in which a propylene-type resin layer contains 0.01-5 weight part of nucleating agents with respect to 100 weight part of propylene * alpha-olefin random copolymers. It exists in the laminated body of any one of Claims 1-5 characterized by these.

The seventh invention of the present invention resides in the laminate according to claim 6, wherein the nucleating agent is a high-density polyethylene component (D) having the following properties (D1) to (D2). .
(D1) Melt flow rate (MFR: 190 ° C., 21.18 N load) is 0.1 to 50 g / 10 min.
(D2) Density is 0.940-0.980 g / cm ³ .

  Moreover, the 8th invention of this invention exists in the laminated body of any one of Claims 1-7 characterized by the total thickness of a laminated body being 100-700 micrometers.

  Moreover, 9th invention of this invention is a ratio of the propylene-type resin layer with respect to the whole thickness of a laminated body being 15 to 60%, The lamination | stacking of any one of Claims 1-8 characterized by the above-mentioned. Exists in the body.

  According to a tenth aspect of the present invention, there is provided a medical bag comprising the laminate according to any one of the first to ninth aspects.

  The laminate of the present invention has not only good hygiene, but also remarkably excellent flexibility, transparency, glossiness and delamination strength after sterilization at 121 ° C., and heat resistance, problems during transportation and handling. Excellent bag drop strength. Therefore, it can be suitably used as a soft container in the medical field such as a medical bag, particularly an infusion bag. Moreover, since the laminated body of this invention is excellent in transparency, a softness | flexibility, heat resistance, and bag drop strength, it can be used suitably also as a food packaging bag for retorts which needs 121 degreeC heat resistance.

  The laminate of the present invention is an ethylene resin obtained by blending 3 to 40% by weight of component (C) with respect to 60 to 97% by weight of component (B) and propylene resin layer containing component (A) as a main component. It is a multilayer laminate composed of at least two layers. Below, the component of the composition which comprises each layer, the shaping | molding method of a laminated body, etc. are demonstrated in detail.

1. Propylene-based resin layer The composition constituting the propylene-based resin layer of the laminate of the present invention contains the following component (A) as a main component and, if necessary, a nucleating agent. As a nucleating agent, it can select and use from a well-known material, for example, a high density polyethylene, ie, a component (D), can be used.

(1) Component (A)
The component (A) used in the laminate of the present invention is a propylene / α-olefin random copolymer polymerized using a metallocene catalyst and having the following properties (A1) to (A3). Preferably, it further has the characteristic of (A4). More preferably, it further has the characteristic (A5).

(I) Monomer constitution The propylene / α-olefin random copolymer used in the present invention is a random copolymer of propylene and an α-olefin mainly composed of a constitutional unit derived from propylene.

The α-olefin used as a comonomer is preferably ethylene or an α-olefin having 4 to 18 carbon atoms. Specifically, ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methyl-pentene-1, 4-methyl-hexene-1, 4,4-dimethylpentene-1 Etc. Moreover, as an alpha olefin, 1 type or the combination of 2 or more types may be sufficient.
Specific examples of the propylene / α-olefin random copolymer include propylene / ethylene random copolymer, propylene / 1-butene random copolymer, propylene / 1-hexene random copolymer, propylene / ethylene / 1- Examples include octene random copolymers and propylene / ethylene / 1-butene random copolymers.

The amount of propylene units in the propylene / α-olefin random copolymer is 85 to 99.5% by weight, preferably 87 to 99.5% by weight, more preferably 88 to 99.5% by weight, and still more preferably 92 to 90%. The amount of α-olefin units (Ec) is 0.5 to 15% by weight, preferably 0.5 to 13% by weight, more preferably 0.5 to 12% by weight, and still more preferably 99.5% by weight. Is 0.5 to 8% by weight. When the amount of the propylene unit is small, the heat resistance of the laminate is lowered, and when too large, the flexibility of the laminate is impaired. Here, the propylene unit and the α-olefin unit are values measured by ¹³ C-NMR under the following conditions.

Apparatus: JEOL-GSX270 manufactured by JEOL Ltd.
Concentration: 300 mg / 2 mL
Solvent: orthodichlorobenzene.

(Ii) Polymerization catalyst and polymerization method The propylene / α-olefin random copolymer used in the present invention can be easily produced by polymerization using a metallocene catalyst. What is a metallocene catalyst?
A. A transition metal compound of Group 4 of the periodic table (so-called metallocene compound) containing a ligand having a cyclopentadienyl skeleton,
B. A cocatalyst capable of reacting with the metallocene compound and activating to a stable ionic state, and if necessary,
C. A catalyst comprising an organoaluminum compound,
Any known catalyst can be used. The metallocene compound is preferably a bridged metallocene compound capable of stereoregular polymerization of propylene, and more preferably a bridged metallocene compound capable of isoregular polymerization of propylene.

  A. Examples of the metallocene compound include JP-A-60-35007, JP-A-61-130314, JP-A-63-295607, JP-A-1-275609, JP-A-2-41303, and JP-A-2-131488. JP-A-2-76887, JP-A-3-163888, JP-A-4-300787, JP-A-4-21694, JP-A-5-43616, JP-A-5-209913, JP-A-6-239914. JP-A-7-504934 and JP-A-8-85708.

  More specifically, methylene bis (2-methylindenyl) zirconium dichloride, ethylenebis (2-methylindenyl) zirconium dichloride, ethylene 1,2- (4-phenylindenyl) (2-methyl-4-phenyl) -4H azulenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, isopropylidene (4-methylcyclopentadienyl) (3-t-butylindenyl) zirconium dichloride, dimethylsilylene (2-methyl) -4-t-butyl-cyclopentadienyl) (3′-t-butyl-5′-methyl-cyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (4,5 6,7-tetrahydroindenyl) zirconium dichloride, dimethylsilylenebis [1- (2-methyl-4-phenylindenyl)] dicuronium dichloride, dimethylsilylenebis [1- (2-ethyl-4-phenylindenyl)] Zirconium dichloride, dimethylsilenebis [4- (1-phenyl-3-methylindenyl)] zirconium dichloride, dimethylsilylene (fluorenyl) t-butylamidozirconium dichloride, methylphenylsilylenebis [1- (2-methyl-4, (1-naphthyl) -indenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-methyl-4,5-benzoindenyl)] disconium dichloride, dimethylsilylene bis [1- (2-methyl-phenyl-4H) -Azulenyl)] Luconium dichloride, dimethylsilylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-ethyl-4-naphthel-4H-azurenyl) Zirconium dichloride, diphenylsilylene bis [1- (2-methyl-4- (4-chlorophenyl) -4H-azulenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-ethyl-4- (3-fluorobiphenylyl) ) -4H-azulenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl- 4-phenolindenyl)] zirconium dichlorine Zirconium compounds such as copper can be exemplified. In the above, compounds in which zirconium is replaced with titanium or hafnium can be used in the same manner. In some cases, a mixture of a zirconium compound and a hafnium compound can be used. Further, the chloride can be replaced with other halogen compounds, hydrocarbon groups such as methyl, isobutyl and benzyl, amide groups such as dimethylamide, alkoxide groups such as methoxy group and phenoxy group, hydride groups and the like. Among these, a metallocene compound in which an indenyl group or an azulenyl group is crosslinked with silicon or a germyl group is preferable.

The metallocene compound may be used by being supported on an inorganic or organic compound carrier. The carrier, porous inorganic compounds or organic compounds are preferred, specifically, ion-exchange layered silicate, _{zeolites, SiO 2, Al 2 O 3} , _{silica-alumina, MgO, ZrO 2, TiO 2} , B Inorganic compounds such as ₂ O ₃ , CaO, ZnO, BaO, ThO ₂ , organic compounds composed of porous polyolefins, styrene / divinylbenzene copolymers, olefin / acrylic acid copolymers, etc., or mixtures thereof .

  B. Co-catalysts that can react with metallocene compounds to be activated to a stable ionic state include organoaluminum oxy compounds (eg, aluminoxane compounds), ion-exchange layered silicates, Lewis acids, boron-containing compounds, ionic compounds, fluorine-containing An organic compound etc. are mentioned.

  C. Examples of the organoaluminum compound include trialkylaluminum such as triethylaluminum, triisopropylaluminum, and triisobutylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, alkylaluminum dihalide, alkylaluminum hydride, and organoaluminum alkoxide.

  Examples of the polymerization method include a slurry method using an inert solvent in the presence of the catalyst, a solution method, a gas phase method substantially using no solvent, or a bulk polymerization method using a polymerization monomer as a solvent. . As a method for obtaining the propylene / α-olefin copolymer specified by the present invention, for example, by adjusting the polymerization temperature and the comonomer amount and appropriately controlling the molecular weight and crystallinity distribution, a desired polymer can be obtained. Can do. Further, the propylene / α-olefin random copolymer may be appropriately selected from those commercially available as metallocene polypropylene. Examples of commercially available products include “Wintech” manufactured by Nippon Polychem.

(Iii) Characteristics (A1) Melt flow rate (MFR: 230 ° C., 21.18 N load)
The MFR of the propylene / α-olefin random copolymer used in the present invention is 0.1 to 50 g / 10 minutes, preferably 1 to 30 g / 10 minutes, more preferably 2 to 20 g / 10 minutes, and still more preferably 4 to 15 g / 10 min. When the MFR is less than the above range, the extrudability is lowered, a suitable productivity cannot be obtained, and further transparency cannot be obtained. When the above range is exceeded, the strength of the laminate is lowered, which is not preferable. In order to adjust the MFR of the polymer, for example, a method of appropriately adjusting the polymerization temperature, the amount of catalyst, the supply amount of hydrogen as a molecular weight regulator and the like is employed.

  In addition, the measurement of MFR is performed based on JIS-K6921-2: 1997 appendix (230 degreeC, 21.18N load).

(A2) Weight average molecular weight (Mw) / Number average molecular weight (Mn)
The ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the propylene / α-olefin random copolymer used in the present invention is 1.5 to 3.5, preferably 1.8. To 3.3, more preferably 2.0 to 3.0. When Mw / Mn exceeds the above range, the transparency is lowered, which is not preferable. When it is less than the above range, processability is deteriorated such that the extrusion load increases and shark skin is easily generated.

  Examples of a method for setting Mw / Mn within a predetermined range include a method for selecting an appropriate metallocene catalyst.

  In addition, the measurement of Mw / Mn is performed by gel permeation chromatography (GPC), and the measurement conditions are as follows.

Apparatus: GPC 150C type manufactured by Waters Inc. Detector: 1A infrared spectrophotometer manufactured by MIRAN (measurement wavelength: 3.42 μm)
Column: AD806M / S, manufactured by Showa Denko Co., Ltd. (Calibration of the column is a monodisperse polystyrene manufactured by Tosoh Corporation (0.5 mg / ml solution of each of A500, A2500, F1, F2, F4, F10, F20, F40, and F288) The measurement was performed and the logarithmic value of the elution volume and molecular weight was approximated by a quadratic equation, and the molecular weight of the sample was converted to polypropylene using the viscosity equation of polystyrene and polypropylene, where the coefficient of the viscosity equation of polystyrene is α = 0.723, log K = −3.767, and polypropylene has α = 0.707, log K = −3.616.)
Measurement temperature: 140 ° C
Concentration: 20 mg / 10 mL
Injection volume: 0.2ml
Solvent: orthodichlorobenzene Flow rate: 1.0 ml / min.

(A3) Melting peak temperature (Tm)
The propylene / α-olefin random copolymer used in the present invention has a melting peak temperature (Tm) measured by a differential scanning calorimeter (DSC) of 121 to 150 ° C., preferably 125 to 150 ° C., more preferably 128 to 145 ° C., More preferably, it is 130-145 degreeC. When Tm is less than the above range, heat resistance and transparency during sterilization at 121 ° C. cannot be obtained, and when it exceeds the above range, flexibility is lacking, which is not preferable.

  Tm can be affected by the α-olefin content, the type thereof, the regioregularity of the propylene structural unit, and the like. When the α-olefin is ethylene, the content is about 0.5 to 6% by weight, and when the α-olefin is 1-butene, the content is about 0.5 to 15% by weight. is there.

  The adjustment of Tm can be appropriately adjusted by controlling the type and amount of α-olefin to be copolymerized.

  The Tm measurement was performed using a Seiko DSC, and the sample amount was 5.0 mg, held at 200 ° C. for 5 minutes, and then crystallized to 40 ° C. at a cooling rate of 10 ° C./minute for 1 minute. The peak temperature when the sample is held and further melted at a heating rate of 10 ° C./min is evaluated. Further, the melting peak temperature (Tm) is sometimes synonymous with the melting point.

(A4) Relationship between melting peak temperature (Tm) and comonomer content (Ec) The propylene / α-olefin random copolymer used in the present invention preferably has the relationship of the following formula (1). More preferably, it has the relationship of the following formula (2), and more preferably has the relationship of the formula (3). The comonomer here is an α-olefin other than propylene copolymerized with propylene, and the amount (Ec) of the comonomer based on the total olefin is 0.5 to 15% by weight, preferably 0.5 to 13% by weight. %, More preferably 0.5 to 12% by weight, still more preferably 0.5 to 8% by weight.

Tm ≧ −6.7049 × Ec + 140 (1)
Tm ≧ −6.7049 × Ec + 145 (2)
Tm ≧ −6.7049 × Ec + 147 (3)
If Tm and Ec do not satisfy the above relational expression, flexibility or heat resistance is deteriorated. Tm can be increased as the isotacticity of the propylene / α-olefin random copolymer is higher when Ec is the same. It can also be increased by using a nucleating agent.

(A5) Isotacticity The propylene / α-olefin random copolymer used in the present invention preferably has a high isotacticity (stereoregularity). The isotacticity is 97% or more, preferably 98% or more, as an isotactic triad fraction ([mm] fraction).

  The [mm] fraction is the ratio of three propylene unit chains in which the direction of methyl branching in each propylene unit is the same among arbitrary three propylene unit chains composed of head-to-tail bonds in the polymer chain. This [mm] fraction is a value indicating that the three-dimensional structure of the methyl group in the polypropylene molecular chain is controlled isotactically.

Here, the [mm] fraction is a value measured according to the following ¹³ C-NMR spectrum measurement method. ^{The 13} C-NMR spectrum was obtained by completely dissolving 350 to 500 mg of a sample in a 10 mmφ NMR sample tube in a solvent obtained by adding 0.5 ml of deuterated benzene as a lock solvent to 2 ml of o-dichlorobenzene. , Measured at 130 ° C. by the proton complete decoupling method. As the measurement conditions, a flip angle of 90 ° and a pulse interval of 5T1 or more (T1 is the longest value among the spin lattice relaxation times of the methyl group) are selected. In the propylene-based polymer, T1 of the methylene group and methine group is shorter than that of the methyl group, so that the recovery of the magnetization of all the carbons is 99% or more under these measurement conditions. Further, for the determination of trace components, integration is performed for 20 hours or more using an NMR apparatus having a resonance frequency of carbon nuclei of 100 MHz or more. The chemical shift is a head-to-tail bond, and the methyl group of the third unit of the 5-unit propylene unit having the same methyl branching direction is set to 21.8 ppm, and the chemical shifts of other carbon peaks are based on this. . In this standard, the peak based on the methyl group of the second unit in the three propylene unit chains represented by [mm] is in the range of 21.2 to 22.5 ppm, and the peak in the three propylene unit chains represented by [mr] The peak based on the methyl group of the second unit is in the range of 20.5 to less than 21.2 ppm, and the peak based on the methyl group of the second unit in the three propylene unit chains represented by [rr] is 19.5. Appears in the range of ~ 20.5 ppm.

  The [mm] fraction is calculated from the ratio of each structure [mm], [mr], [rr] by the following formula.

ただしＰＰＰ［ｍｍ］、ＰＰＰ［ｍｒ］及びＰＰＰ［ｒｒ］はそれぞれ頭−尾結合したプロピレン単位３連鎖における［ｍｍ］、［ｍｒ］、［ｒｒ］各構造の割合を表し、各ピークに帰属される領域の面積から評価される。

However, PPP [mm], PPP [mr], and PPP [rr] represent the ratio of [mm], [mr], and [rr] structures in propylene units linked by head-to-tail, respectively, and are assigned to each peak. It is evaluated from the area of the area.

(2) Nucleating agent The component constituting the propylene-based resin layer of the laminate of the present invention may contain a nucleating agent in the component (A). From the viewpoint of

  As a nucleating agent mix | blended with a component (A), what is necessary is just to improve the progress rate of the crystal nucleus production | generation process of a propylene and an alpha olefin random copolymer. Generally, crystallization of polypropylene consists of two processes: a crystal nucleation process and a crystal growth process. In the crystal nucleation process, the temperature difference from the crystallization temperature and the orientation behavior of molecular chains The rate of non-uniform crystal nucleation is significantly increased due to the presence of a substance that affects the speed, particularly through the adsorption of molecular chains and the like, and promotes molecular chain orientation.

Specific examples of the nucleating agent include crystalline polymer compounds such as high density polyethylene. Particularly preferred is a high-density polyethylene having the following properties (D1) and (D2), that is, component (D).
(D1) Melt flow rate (MFR: 190 ° C., 21.18 N load)
The MFR of component (D) is 0.1 to 3000 g / 10 minutes, preferably 10 to 100 g / 10 minutes, and more preferably 10 to 20 g / 10 minutes. When the MFR of component (D) is less than 0.1 g / 10 minutes, the dispersion diameter of polyethylene is not sufficiently reduced, and the dispersed particles are reflected as irregularities on the film surface, leading to deterioration of transparency. In order to finely disperse polyethylene, the MFR of component (D) is preferably larger than the MFR of the propylene / α-olefin copolymer.

  In addition, MFR of a component (D) is measured based on JIS-K6922-2: 1997 appendix (190 degreeC, 21.18N load).

(D2) Density The density of the component (D) is 0.940 to 0.980 g / cm ³ , preferably 0.950 to 0.980 g / cm ³ , more preferably 0.960 to 0.980 g / cm ³ . is there. When the density of the component (D) is less than 0.940 g / cm ³ , the effect of improving transparency is not sufficient, and it is difficult to produce polyethylene exceeding 0.980 g / cm ³ .

  In addition, the density of a component (D) is measured based on JIS-K6922-2: 1997 appendix (23 degreeC).

  Production of high density polyethylene used as a nucleating agent in the present invention is not particularly limited with respect to the polymerization method and catalyst as long as a polymer having the desired physical properties can be produced, but polyethylene obtained by an intermediate pressure process is preferred.

  For catalysts, Ziegler type catalysts (ie, based on a combination of supported or unsupported halogen-containing titanium compounds and organoaluminum compounds), Kaminsky type catalysts (ie, supported or unsupported metallocene compounds and organoaluminum compounds, especially alumoxanes). Based on the combination).

  The Ziegler-type catalyst can be obtained by a usual polymerization method using, for example, a combination catalyst of a solid catalyst component and an organoaluminum compound containing magnesium halide, titanium halide, and an electron donor compound as components. The shape of polyethylene is not limited, and may be any of pellets, powders, and waxes.

  Examples of the nucleating agent other than the crystalline polymer compound include dibenzylidene sorbitol or a derivative thereof, an organic phosphate compound or a metal salt thereof, an aromatic sulfonate or a metal salt thereof, an organic carboxylic acid or a metal salt thereof, and a rosin acid partial metal. Examples thereof include inorganic fine particles such as salts and talc, imides, amides, quinacridonequinones, and mixtures thereof. Among them, a dibenzylidene sorbitol derivative, an organic phosphate metal salt, an organic carboxylic acid metal salt, and the like are preferable because of excellent transparency.

  Specific examples of the dibenzylidene sorbitol derivative include 1,3: 2,4-bis (o-3,4-dimethylbenzylidene) sorbitol and 1,3: 2,4-bis (o-2,4-dimethylbenzylidene). Sorbitol, 1,3: 2,4-bis (o-4-ethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-chlorobenzylidene) sorbitol, 1,3: 2,4-dibenzylidene Sorbitol is mentioned.

  Specific examples of the organic phosphate metal salt include compounds represented by the following general formula (I).

（式中、Ｒ¹は水素原子または炭素数１〜４のアルキル基を示し、Ｒ²およびＲ³はそれぞれ水素原子、炭素数１〜１２のアルキル基、シクロアルキル基、アリール基またはアラルキル基を示す。Ｍはアルカリ金属、アルカリ土類金属、アルミニウム、亜鉛のいずれかを示し、Ｍがアルカリ金属のときｍは０を、ｎは１を示し、Ｍが二価金属のときｎは１または２を示し、ｎが１のときｍは１を、ｎが２のときｍは０を示し、Ｍがアルミニウムのときｍは１を、ｎは２を示す。）
安息香酸金属塩の具体例としては、ヒドロキシ−ジ（ｔ−ブチル安息香酸）アルミニウム等が挙げられる。

(In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² and R ³ represent a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an aryl group, or an aralkyl group, respectively. M represents any one of alkali metal, alkaline earth metal, aluminum and zinc, m represents 0 when M is an alkali metal, n represents 1, and n represents 1 or 2 when M is a divalent metal. When n is 1, m is 1, when n is 2, m is 0, when M is aluminum, m is 1, and n is 2.)
Specific examples of the metal benzoate include hydroxy-di (t-butylbenzoate) aluminum.

  When mix | blending a nucleating agent with the propylene-type resin layer used by this invention, the compounding quantity of a nucleating agent is 0.01-5 weight part of nucleating agents with respect to 100 weight part of components (A). The preferred range varies depending on the nucleating agent used, and in the case of a sorbitol derivative, phosphate compound, or benzoate compound, preferably 0.01 to 3 parts by weight of the nucleating agent with respect to 100 parts by weight of the component (A), More preferably 0.01 to 1 part by weight of the nucleating agent with respect to 100 parts by weight of the component (A), and particularly preferably 0.01 to 0.5 part by weight of the nucleating agent with respect to 100 parts by weight of the component (A). is there.

  In the case of high-density polyethylene, preferably 0.05 to 5 parts by weight of nucleating agent with respect to 100 parts by weight of component (A), more preferably 0.1 to 0.1 parts of nucleating agent with respect to 100 parts by weight of component (A). 5 parts by weight, particularly preferably 0.3 to 2 parts by weight of the nucleating agent with respect to 100 parts by weight of the component (A).

  If the nucleating agent is less than 0.01 parts by weight, the effect of improving the transparency is not sufficient. On the other hand, if the nucleating agent exceeds 5 parts by weight, the nucleating agent is aggregated to form a solid. There arises a problem that it is formed and the transparency is impaired.

(3) Other compounding components In the component of the propylene-based resin layer of the present invention, other additional optional components can be blended within a range that does not significantly impair the effects of the present invention. Examples of such optional components include antioxidants, clarifying agents, lubricants, antiblocking agents, antistatic agents, antifogging agents, neutralizing agents, metal deactivators, and colorants used in ordinary polyolefin resin materials. , Dispersants, peroxides, fillers, fluorescent brighteners, and the like.

  In addition, the high pressure radical polymerization method low density polyethylene, linear low density polyethylene, ethylene / α-olefin copolymer, isotactic polypropylene, propylene / α-olefin block copolymer, olefin, as long as the effects of the invention are not impaired. A series elastomer, a styrene elastomer or the like can also be mixed.

(4) Adjustment of resin material The material composed mainly of component (A) used for the propylene-based resin layer is a mixture of the above essential component (A) and a nucleating agent, additional components, etc., which are blended as necessary. And obtained by melt kneading.

  For melt kneading, for example, each component in the form of powder, pellets, etc. is a uniaxial or biaxial extruder, Banbury mixer, kneader blender, Brabender plastograph, small batch mixer, continuous mixer, mixing roll, etc. To do. The kneading temperature is generally 180 to 270 ° C. In addition, the kneader can be a combination of two or more of those described above.

2. Ethylene resin layer The composition which comprises the ethylene resin layer of the laminated body of this invention consists of a composition of 60 to 97 weight% of a component (B), and 3 to 40 weight% of a component (C). Component (B) is an ethylene / α-olefin copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms, and component (C) is high-density polyethylene.

(1) Component (B)
Component (B) used in the laminate of the present invention has the following properties (B1) to (B2), preferably polymerized with a metallocene catalyst, and further has the properties (B3) to (B4). -Olefin copolymer.

(I) Monomer configuration The ethylene / α-olefin copolymer used in the present invention is a random copolymer of ethylene and an α-olefin mainly composed of a structural unit derived from ethylene.

  The α-olefin used as a comonomer is preferably an α-olefin having 3 to 12 carbon atoms. Specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methyl-pentene-1, 4-methyl-hexene-1, 4,4-dimethylpentene- 1 etc. can be mentioned. Specific examples of such ethylene / α-olefin copolymers include ethylene / propylene copolymers, ethylene / 1-butene copolymers, ethylene / 1-hexene copolymers, ethylene / 1-octene copolymers, ethylene -4-methyl-pentene-1 copolymer is mentioned. Moreover, 1 type, or 2 or more types of combination may be sufficient as an alpha olefin. When two types of α-olefins are combined to form a terpolymer, ethylene / propylene / hexcenter polymer, ethylene / butene / hexcenter polymer, ethylene / propylene / octene terpolymer, and ethylene / butene / octene terpolymer may be mentioned. .

  The amount of ethylene units in the ethylene / α-olefin copolymer will be described later as the characteristic (B3).

(Ii) Polymerization Catalyst and Polymerization Method The ethylene / α-olefin copolymer used in the present invention can be produced using a Ziegler catalyst, preferably a metallocene catalyst. Examples of the production method include a high-pressure ion polymerization method, a gas phase method, a solution method, and a slurry method.

(Iii) Characteristics (B1) Melt flow rate (MFR: 190 ° C., 21.18 N load)
The MFR of the ethylene / α-olefin copolymer used in the present invention is 0.1 to 20 g / 10 min, preferably 0.5 to 10 g / 10 min, and more preferably 10 to 5 g / 10. Minutes. When the MFR of the ethylene / α-olefin copolymer is less than 0.1 g / 10 min, the resin pressure is high and the moldability is poor, and when it exceeds 20 g / 10 min, the bubbles become unstable during inflation molding and the moldability is poor. become.

  The MFR of the ethylene / α-olefin copolymer is measured in accordance with JIS-K6922-2: 1997 appendix (190 ° C., 21.18 N load).

(B2) Density Density of the ethylene · alpha-olefin copolymer used in the present invention, 0.880~0.930g / cm ^3, preferably 0.890~0.925g / cm ^3, more preferably 0.900 ˜0.923 g / cm ³ . When the density of the ethylene / α-olefin copolymer is less than 0.880 g / cm ³ , poor transparency occurs after the treatment at 121 ° C., and when it exceeds 0.930 g / cm ³ , it is preferable because of poor transparency and reduced flexibility. Absent.

  The density of the ethylene / α-olefin copolymer is measured in accordance with JIS-K6922-2: 1997 appendix (in the case of low density polyethylene) (23 ° C.).

(B3) Content of α-olefin The content of α-olefin in the ethylene / α-olefin copolymer used in the present invention is preferably 5 to 40% by weight, more preferably 7 to 35% by weight, still more preferably. Is 9-30% by weight. When the α-olefin content is low, the impact strength and flexibility of the film cannot be obtained, and when it is too high, the heat resistance is impaired. Here, the content of α-olefin is a value measured by ¹³ C-NMR method under the following conditions.

Device: JEOL-GSX270 manufactured by JEOL
Concentration: 300 mg / 2 mL
Solvent: orthodichlorobenzene.

(B4) Ratio of Z average molecular weight (Mz) to number average molecular weight (Mn) (Mz / Mn)
The ratio (Mz / Mn) of the Z average molecular weight (Mz) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) of the ethylene / α-olefin copolymer used in the present invention is 8.0. The following is preferable, and more preferably 5.0 or less. When (Mz / Mn) exceeds 8, transparency deteriorates. Examples of a method for adjusting (Mz / Mn) to a predetermined range include a method for selecting an appropriate metallocene catalyst.

  In addition, the measurement of (Mz / Mn) is performed by gel permeation chromatography (GPC), and the measurement conditions are as follows.

Apparatus: GPC 150C type manufactured by Waters Inc. Detector: 1A infrared spectrophotometer manufactured by MIRAN (measurement wavelength: 3.42 μm)
Column: Showa Denko 3 AD806M / S (column calibration is Tosoh monodisperse polystyrene (0.5 mg / ml solution each of A500, A2500, F1, F2, F4, F10, F20, F40, F288) The logarithm of the elution volume and molecular weight was approximated by a quadratic equation, and the molecular weight of the sample was converted to polyethylene using the viscosity equation of polystyrene and polyethylene, where the coefficient of the viscosity equation of polystyrene was α = 0. 723, log K = −3.967, and polyethylene has α = 0.733 and log K = −3.407.)
Measurement temperature: 140 ° C
Concentration: 20 mg / 10 mL
Injection volume: 0.2ml
Solvent: orthodichlorobenzene Flow rate: 1.0 ml / min.

  Since Mz contributes greatly to the average molecular weight of the high molecular weight component, (Mz / Mn) is easier to confirm the presence of the high molecular weight component than (Mw / Mn). The high molecular weight component is a factor that affects the transparency, and when the high molecular weight component is large, the transparency is deteriorated. Therefore, a smaller Mz / Mn is preferable.

(2) Component (C)
The component (C) used in the laminate of the present invention is a high density polyethylene having the following properties (C1) to (C2).
(I) Characteristics (C1) Melt flow rate (MFR: 190 ° C., 21.18 N load)
The MFR of the component (C) used in the present invention is 0.1 to 50 g / 10 minutes, preferably 1 to 30 g / 10 minutes, more preferably 2 to 9 g / 10 minutes. When the MFR of the component (C) is less than 0.1 g / 10 minutes, the dispersibility in the component (B) is lacking, so the heat resistance during the 121 ° C. treatment is not improved, which is not preferable. On the other hand, if the MFR exceeds 50 g / 10 min, the film formation stability is not preferred. In addition, MFR of high density polyethylene is measured based on JIS-K6922-2: 1997 appendix (190 degreeC, 21.18N load).

(C2) Density The density of the component (C) used in the present invention is 0.940 to 0.980 g / cm ³ , preferably 0.950 to 0.980 g / cm ³ , more preferably 0.960 to 0.980 g. / Cm ³ . When the density of the component (C) is less than 0.940 g / cm ³ , the effect of improving heat resistance is not sufficient, and it is difficult to produce polyethylene exceeding 0.980 g / cm ³ . In addition, the density of a component (C) is measured based on JIS-K6922-2: 1997 appendix (23 degreeC).

(Ii) Polymerization Method and Polymerization Catalyst The production of component (C) of the present invention is not particularly limited with respect to the polymerization method and catalyst as long as a polymer having the desired physical properties can be produced, but polyethylene obtained by an intermediate pressure process. Is preferred.

  For catalysts, Ziegler type catalysts (ie, based on a combination of supported or unsupported halogen-containing titanium compounds and organoaluminum compounds), Kaminsky type catalysts (ie, supported or unsupported metallocene compounds and organoaluminum compounds, especially alumoxanes). Based on the combination).

  The Ziegler-type catalyst can be obtained by an ordinary polymerization method using, for example, a combination catalyst of a solid catalyst component and an organoaluminum compound containing magnesium halide, titanium halide, and an electron donor compound as components.

  The shape of polyethylene is not limited, and may be any of pellets, powders, and waxes.

(3) Blending ratio of component (B) and component (C) The blending ratio of the ethylene-based resin layer is 60 to 97% by weight for component (B) and 3 to 40% by weight for component (C). Preferably, component (B) is 70 to 95% by weight, component (C) is 5 to 30% by weight, more preferably component (B) is 80 to 95% by weight, and component (C) is 5%. -20% by weight. When the proportion of the component (C) is less than 3% by weight, the effect of improving heat resistance is not seen. On the other hand, when the compounding ratio of the component (C) exceeds 40% by weight, the flexibility and transparency deteriorate, which is not preferable.

(4) Other additive components In the resin component which comprises the ethylene-type resin layer of this invention, another additional arbitrary component can be mix | blended in the range which does not impair the effect of this invention remarkably. Examples of such optional components include antioxidants, crystal nucleating agents, clearing agents, lubricants, colorants, dispersants, peroxides, fillers, fluorescent brighteners and the like used in ordinary polyolefin resin materials. Can be mentioned.

  In addition, the high pressure radical polymerization method low density polyethylene, linear low density polyethylene, ethylene / α-olefin copolymer, isotactic polypropylene, propylene / α-olefin block copolymer, olefin, as long as the effects of the invention are not impaired. A series elastomer, a styrene elastomer or the like can also be mixed.

3. Laminated body The laminated body of this invention should just be the said propylene-type resin layer laminated | stacked on the one side or both sides of the said ethylene-type resin layer. When laminating on both sides, the propylene-based resin layers may be the same or different. In addition to the propylene-based resin layer and the ethylene-based resin layer, various layers generally used in such a laminate can be additionally provided as necessary. Specifically, an adhesive layer or a gas barrier layer such as saponified ethylene / vinyl acetate copolymer (EVOH) or nylon can be provided between the various layers.

  The haze (HAZE) of the laminate of the present invention is preferably 32% or less, more preferably 25% or less after 121 ° C. treatment. If the haze exceeds 32%, the contents are not clearly visible, such as inferior commercial value. In addition, the haze of the film in this invention is measured based on JIS-K7136-2000.

  In the present invention, the thickness of the entire laminate is preferably 100 to 700 μm. If it is in the said range, since the film excellent in transparency can be shape | molded stably, it is preferable. Furthermore, the laminate obtained in the present invention can be subjected to a surface treatment such as a corona discharge treatment or a flame treatment by a method usually used industrially.

  Moreover, 15 to 60% is preferable and, as for the ratio of the polypropylene-type resin layer with respect to the whole thickness in the laminated body in this invention, More preferably, it is 15 to 50%. If the thickness of the propylene-based resin layer is less than 15%, heat resistance is insufficient, and if it exceeds 60%, flexibility is not preferable.

Further, when the propylene-based resin layer is laminated on both sides of the ethylene-based resin layer, 5 ethylene / α-olefin copolymers having a density of 0.88 to 0.930 g / cm ³ are added to one propylene-based resin layer. A method of blending ˜40% by weight is also used as a preferable means. By doing so, when making a bag, when sealing with a seal bar from a propylene-based resin layer not containing ethylene / α-olefin, the seal bar contact surface is not taken by the bar because it can be sealed at a lower temperature. It becomes possible to seal and work efficiency increases. A similar effect can be obtained by providing a difference in melting point between the propylene-based resin layers.

4). Use The laminated body obtained by this invention can be used for a medical bag, a food packaging bag, etc. In particular, it can be suitably used for 121 ° C. sterilization treatment requiring heat resistance. Specific applications of the medical bag include infusion bags, containers for injecting, discharging, and storing body fluids and drug solutions, peritoneal dialysis bags, artificial dialysis bags, and the like. Examples of food packaging bags include retort food bags.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The evaluation methods and resins used in the examples and comparative examples are as follows.

1. Evaluation Method of Resin Physical Properties (1) Melt Flow Rate (MFR): As described above, the MFR of the propylene / α-olefin random copolymer is JIS-K6921-2: 1997 appendix (230 ° C., 21.18 N load). The MFR of the ethylene / α-olefin copolymer and the high density polyethylene was measured in accordance with JIS-K6922-2: 1997 appendix (190 ° C., 21.18 N load).
(2) Tm: As described above, measured by DSC.
(3) Mw / Mn: Measured by GPC as described above.
(4) Mz / Mn: Measured by GPC as described above.
(5) Density: As described above, the density of the ethylene / α-olefin random copolymer is measured according to JIS-K6922-2: 1997 appendix (23 ° C., in the case of low density polyethylene). The density of polyethylene was measured according to JIS-K6922-2: 1997 appendix (23 ° C.).

2. Forming method of laminated body Three types of three-layer water-cooled inflation molding machine (die diameter: 100 mmφ, die lip: 3 mm, die temperature: 185 ° C.) manufactured by Plako Corporation, the thickness of the first layer and the third layer is 50 μm, A tubular laminate having a thickness of 150 μm and a folding diameter of 180 mm was formed. The first layer was laminated on one side of the second layer, and the third layer was laminated on the other side.

3. Laminate Evaluation Method (1) Heat Resistance A cylindrical laminate was cut into a size of 210 mm, and one of the cut out was heat-sealed into a bag shape. Next, 500 ml of pure water was filled therein, and the other side was heat-sealed and sealed. Sealing was performed such that the distance between the heat seal and the heat seal was 180 mm. The sample bag thus obtained is put into a high-temperature and high-pressure cooking sterilization tester (manufactured by Nisaka Seisakusho, RCS / 40RTGN type) and then pressurized, and the ambient temperature is increased to 121 ° C. Hold for 30 minutes. Then, it cooled to about 40 degreeC and took out this sample bag from the testing machine. Hereinafter, this sterilized “sample bag” will be referred to as a “layer after sterilization”.

Each heat seal was performed under the conditions of temperature: 200 ° C., pressure: 2 kg / cm ² , and time: 4 seconds.

The heat resistance of the sample bag was evaluated according to the following criteria.
X: There are many wrinkles. Or, transparency is lowered.
○: Almost no wrinkles. Or not at all.

(2) Haze
As described above, measurement was performed according to JIS-K7136-2000. The HAZE measurement was performed on the molded laminate and the sterilized laminate. When measuring the HAZE of the laminate after sterilization, the water filled in the laminate was taken out and 2 hours later.

(3) Tensile modulus (MD)
Based on ISO1184-1983, the tensile elastic modulus of the laminate in the MD direction (film or sheet take-up direction) was measured. It shows that it is excellent in the softness, so that this value is small. In addition, the tensile elasticity modulus was performed about what drained water from the laminated body after sterilization (use the laminated body 48 hours after draining water).

(4) Bag drop strength After the sterilization treatment, the laminates (2 pieces) were stored at 10 ° C. for 24 hours, and then dropped at a temperature from a height of 2 m onto the iron plate in parallel for evaluation. Evaluation was made according to the following criteria.
X: One or two laminates were broken after sterilization.
○: The state did not change from before the drop test, and there was no problem with both.

(5) Glossiness Based on JISK7105-1981, the 60 degree specular glossiness of the laminate was measured after sterilization. The glossiness was measured from the first layer side. It shows that it is excellent in gloss, so that this value is large. The glossiness was measured for the sterilized laminate from which water was drained (use the laminate after 48 hours after draining water).

(6) Interlaminar peel strength Using a gelbo flex tester with the following specifications manufactured by Ritsumei Keiki Co., Ltd., the laminate was bent after sterilization. As the test piece, the one obtained by draining water from the laminate after sterilization (use the laminate after draining water for 48 hours) was used. In order to ensure the size, one of the folds of the tubular sample was cut open and used as a test piece.

Specifications of Gervoflex tester ・ Fixed head: Diameter 88.9 mm, thickness 12.7 mm disc ・ Give 400 ° twist during 82.55 mm stroke ・ Bending speed: 100 strokes / min ・ Specimen size: 21 cm × 29cm
The number of bends was set to 5000 times, and then evaluated according to the following criteria.
X: Delamination was observed in the laminate after sterilization. When the peeling margin was peeled off by hand, the interlayer was easily peeled off.
○: No delamination was observed in the laminate after sterilization.

4). Resin (1) Component (A): Propylene / α-olefin random copolymer (PP-1) to (PP-3) obtained in the following Production Examples 1 to 3 were used. The physical properties are shown in Table 1.

<Production Example 1>
(I) Metallocene compound According to the method described in Example 12 of JP-A-10-226712, a racemic dimethylsilylenebis (2-methyl-4- (4-chlorophenyl) -4H-azurenyl) zirconium dichloride was synthesized. did.
(Ii) Chemical treatment of ion-exchange layered silicate It was produced according to the method described in Example 1 of JP-A-11-80229. Further, 200 g of this chemically treated montmorillonite was introduced into a glass reactor equipped with a stirring blade having an internal volume of 3 L, 750 ml of normal heptane, and a heptane solution (500 mmol) of trinormal octyl aluminum were added and stirred at room temperature. After 1 hour, the slurry was washed with normal heptane (residual liquid ratio less than 1%), and the slurry was adjusted to 2000 mL.
(Iii) Preparation of catalyst / preliminary polymerization Next, 870 mL of toluene slurry of 3 mmol of (r) -dimethylsilylenebis [2-methyl-4- (4-chlorophenyl) -4H-azurenyl] zirconium dichloride and triisobutylaluminum (15 mmol) A mixture obtained by reacting 42.6 mL of the heptane solution in advance at room temperature for 1 hour was added to the chemically treated montmorillonite slurry and stirred for 1 hour.

  Subsequently, 2.1 L of normal heptane was introduced into a stirring autoclave having an internal volume of 10 L which had been sufficiently substituted with nitrogen, and maintained at 40 ° C. The previously prepared montmorillonite / complex slurry was introduced there. When the temperature was stabilized at 40 ° C., propylene was supplied at a rate of 100 g / hour, and the temperature was maintained. After 4 hours, the propylene feed was stopped and maintained for another 2 hours. About 3 L of the supernatant was removed from the recovered prepolymerized catalyst slurry, 170 ml of a heptane solution of triisobutylaluminum (30 mmol) was added, and the mixture was stirred for 10 minutes and then heat-treated at 40 ° C. under reduced pressure. By this operation, a prepolymerized catalyst containing 2.08 g of polypropylene per 1 g of catalyst was obtained.

(Iv) Manufacture of propylene / ethylene random copolymer Internal phase 270L liquid phase polymerization tank with stirrer, internal volume 400L deactivation tank, slurry circulation pump, deactivation system consisting of circulation line, double pipe heat exchange A propylene / ethylene copolymer was continuously produced by a process incorporating a high-pressure degassing system comprising a vessel and a fluidized flash tank, and a post-treatment system including a low-pressure degassing tank and a dryer.

  The prepolymerized catalyst produced above was dispersed in liquid paraffin (manufactured by Tonen Inc .: White Rex 335) at a concentration of 15% by weight and introduced into the liquid phase polymerization tank at 0.52 g / hr as a catalyst component. Furthermore, liquid propylene was continuously supplied to this polymerization tank at 38 kg / hr, ethylene at 0.77 kg / hr, hydrogen at 0.10 g / hr, and triisobutylaluminum at 9.0 g / hr, and the internal temperature was raised to 70 ° C. Hold and polymerize.

From the liquid tank polymerization tank, a mixed slurry of polymer and liquid propylene was extracted as a polymer into an inactivation tank so as to be 11 kg / hr. At this time, the average residence time of the catalyst in the polymerization tank was 1.3 hours. Ethanol was supplied to the deactivation layer at 10.5 g / hr as a deactivation agent. Further, the polymer was extracted from the circulation line to a high-pressure degassing tank, and further dried through a low-pressure degassing tank and a dryer. The internal temperature of the dryer was adjusted to 80 ° C. and the residence time was 1 hour, and a dryer at room temperature was flowed at a flow rate of 12 m ³ / hr in the countercurrent direction of the powder flow. The polymer (PP-1) after drying was taken out from the hopper.

  The obtained polymer (PP-1) had an ethylene content of 2.0% by weight, MFR = 7 g / 10 minutes, Tm = 135 ° C., and Mw / Mn = 2.8.

<Production Example 2>
In Production Example 1 (iv), propylene / ethylene copolymerization was carried out in the same manner as in Production Example 1 except that ethylene was 1.50 kg / hr, hydrogen was 0.20 g / hr, and the internal temperature was 60 ° C. . As a result, a polymer (PP-2) having an ethylene content of 4.4% by weight, MFR = 6 g / 10 minutes, Tm = 120 ° C., and Mw / Mn = 2.8 was obtained.

<Production Example 3>
(1) introducing n- heptane 200mL of dehydrated and deoxygenated prepared sufficiently replaced with nitrogen flask solid catalyst, then MgCl ₂ 0.4 mol, Ti a _{(O-n-C 4 H} 9) 4 0. 8 mol was introduced and reacted for 2 hours while maintaining at 95 ° C. After completion of the reaction, the temperature was lowered to 40 ° C., and then 48 mL of methyl hydrogen polysiloxane (20 centistokes) was introduced and reacted for 3 hours. The resulting solid component was washed with n-heptane.

Next, 50 mL of the produced n-heptane was introduced into a flask sufficiently purged with nitrogen, and 0.24 mol of the solid component synthesized above was introduced in terms of Mg atoms. Furthermore, 0.4 mol of 25 mL SiCl ₄ of n-heptane was mixed and introduced into the flask over 60 minutes while maintaining the temperature at 30 ° C., and reacted at 90 ° C. for 3 hours. Further, 0.016 mol of phthalic acid chloride was mixed with 25 mL of n-heptane, introduced into the flask over 30 minutes while maintaining at 90 ° C., and reacted at 90 ° C. for 1 hour.

After completion of the reaction, washing with n-heptane was performed. Then introducing 0.24mmol the SiCl ₄ thereto, and reacted for 3 hours at 100 ° C.. After completion of the reaction, it was thoroughly washed with n-heptane. 50 mL of sufficiently purified n-heptane was introduced into a flask thoroughly purged with nitrogen, then 5 grams of the solid component obtained above was introduced, and (CH ₃ ) ₃ CSi (CH ₃ ) (OCH ₃ ) ₂ was added to a concentration of 0. It was contacted at 81 mL and 30 ° C. for 2 hours. After completion of the contact, it was washed with n-heptane. Furthermore, prepolymerization was carried out by flowing propylene to obtain a solid catalyst.

(2) Polymerization After the inside of a stirring autoclave having an internal volume of 200 liters was sufficiently substituted with propylene, 60 liters of purified n-heptane was introduced into this, 15 g of triethylaluminum and 2.0 g of the above-mentioned solid catalyst (prepolymerized polymer) Was introduced at 55 ° C. in a propylene atmosphere. Thereafter, the temperature was raised to 60 ° C., and propylene was introduced at a feed rate of 5.8 kg / hr while maintaining the gas phase hydrogen concentration at 5.8% by volume. After another 10 minutes, ethylene was introduced at a rate of 240 g / h, and polymerization was carried out for 6 hours. Thereafter, the supply of all monomers was stopped and polymerization was carried out for 1 hour. Here, the reaction was stopped with butanol. Thereafter, the residual gas was purged, and the product was filtered and dried. As a result, a polymer (PP-3) produced with a Ziegler catalyst and having MFR = 7 g / 10 min, Tm = 138 ° C., and Mw / Mn = 3.9 was obtained.

（２）成分（Ｂ）： エチレン・α−オレフィン共重合体
下記の製造例４〜６で得た（ＰＥ−１）〜（ＰＥ−３）を用いた。物性を表２に示す。

(2) Component (B): Ethylene / α-olefin copolymer (PE-1) to (PE-3) obtained in the following Production Examples 4 to 6 were used. The physical properties are shown in Table 2.

<Production Example 4>
(4-1) A copolymer of ethylene and hexene-1 was produced. The catalyst was prepared by the method described in JP-T-7-508545. That is, to the complex dimethylsilylene bis (4,5,6,7-tetrahydroindenyl) hafnium dimethyl 2.0 mmol, tripentafluorophenyl boron is added in an equimolar amount to the complex, and diluted to 10 liters with toluene. A catalyst solution was prepared.
(4-2) Polymerization A stirred autoclave type continuous reactor having an internal volume of 1.5 liters was maintained at a pressure of 130 MPa, and a mixture of ethylene and 1-hexene had a composition of 1-hexene of 50% by weight. The raw material gas was continuously supplied at a rate of 40 kg / hour. The catalyst solution was continuously supplied, and the supply amount was adjusted so that the polymerization temperature was maintained at 156 ° C. The polymer production per hour was about 2.6 kg. After completion of the reaction, an ethylene / 1-hexene copolymer (1-hexene content = 11 wt%, MFR = 2.2 g / 10 min, density = 0.910 g / cm ³ , Mz / Mn = 3.5) PE-1) was obtained.

<Production Example 5>
Catalyst preparation and polymerization were carried out in the same manner as in Production Example 4 except that the composition of 1-hexene during polymerization was 44% by weight and the polymerization temperature was changed to 160 ° C. The polymer production per hour was about 2.6 kg. After completion of the reaction, 1-hexene content = 9.0 wt%, MFR = 2.2 g / 10 min, density ^{= 0.914g / cm 3, Mz /} Mn = from 3.5 ethylene-1-hexene copolymerization A coalescence (PE-2) was obtained.

<Production Example 6>
Catalyst preparation and polymerization were carried out in the same manner as in Production Example 4 except that the composition of 1-hexene at the time of polymerization was 77% by weight and the polymerization temperature was changed to 105 ° C. The polymer production per hour was about 1.8 kg. After completion of the reaction, an ethylene / 1-hexene copolymer (content of 1-hexene = 32% by weight, MFR = 1.0 g / 10 min, density = 0.865 g / cm ³ , Mz / Mn = 3.5) PE-3) was obtained.

（３）成分（Ｃ）： 高密度ポリエチレン
日本ポリケム社製ノバテックＨＪ５６２（ＭＦＲ：７ｇ／１０分、密度：０．９６２ｇ／ｃｍ³）を用いた。表３中、ＨＤ−Ｃと表示した。

(3) Component (C): High-density polyethylene Novatec HJ562 (MFR: 7 g / 10 min, density: 0.962 g / cm ³ ) manufactured by Nippon Polychem was used. In Table 3, indicated as HD-C.

(4) Component (D): High-density polyethylene Novatec HJ580 (MFR: 12 g / 10 min, density: 0.960 g / cm ³ ) manufactured by Nippon Polychem was used. In Table 3, it was displayed as HD-D.

[Example 1]
For the first layer and the third layer, propylene-based resin 1 in which 0.5 parts by weight of the high-density polyethylene of component (D) is blended with 100 parts by weight of (PP-1) is used. PE-1) Ethylene resin 1 containing 10% by weight of component (C) with respect to 90% by weight was used. The resin material of each layer was set in the above-mentioned Plako 3 type three-layer water-cooled inflation molding machine, and water-cooled inflation molding was performed under the above conditions to obtain a laminate having a thickness of 250 μm and evaluated. The results are shown in Table 3.

[Example 2]
A laminate was obtained in the same manner as in Example 1 except that the second layer was composed of 90% by weight of (PE-2) and 10% by weight of the high-density polyethylene of component (C). It was. The evaluation results are shown in Table 3.

[Example 3]
A laminate was obtained in the same manner as in Example 1 except that ethylene resin 1 was used for the third layer. The evaluation results are shown in Table 3.

[Comparative Example 1]
A laminate was obtained using propylene-based resin 1 for all of the first to third layers. The evaluation results are shown in Table 4. This product has good heat resistance, transparency (after sterilization treatment), gloss (after sterilization treatment) and delamination strength (after sterilization treatment), but is inferior in flexibility and bag drop strength.

[Comparative Example 2]
A laminate was obtained in the same manner as in Example 1 except that 100% by weight of (PE-1) was used for the second layer. The evaluation results are shown in Table 4. This product has good flexibility, drop bag strength and delamination strength (after sterilization treatment), but is inferior in heat resistance, transparency (after sterilization treatment), and gloss (after sterilization treatment).

[Comparative Example 3]
A laminate was obtained in the same manner as in Example 1 except that 100% by weight of (PE-3) was used for the second layer. The evaluation results are shown in Table 4. This product has good flexibility, drop bag strength and delamination strength (after sterilization treatment), but is inferior in heat resistance, transparency (after sterilization treatment), and gloss (after sterilization treatment).

[Comparative Example 4]
A laminate was obtained in the same manner as in Example 1 except that the second layer used was an ethylene resin 3 in which 90% by weight of (PE-3) was blended with 10% by weight of the high-density polyethylene of component (C). It was. The evaluation results are shown in Table 4. This product has good flexibility, drop bag strength, gloss (after sterilization treatment) and delamination strength (after sterilization treatment), but is inferior in heat resistance and transparency (after sterilization treatment).

[Comparative Example 5]
Example 1 except that propylene-based resin 2 in which 0.5 parts by weight of high-density polyethylene of component (D) was blended with 100 parts by weight of (PP-2) in the first layer and the third layer was used. In the same manner, a laminate was obtained. The evaluation results are shown in Table 4. This product has good flexibility, drop bag strength and delamination strength (after sterilization treatment), but is inferior in heat resistance, transparency (after sterilization treatment) and gloss (after sterilization treatment).

[Comparative Example 6]
A laminate was obtained in the same manner as in Example 1 except that 100 wt% of (PP-3) was used for the first layer and the third layer. The evaluation results are shown in Table 4. This product has good flexibility and drop bag strength, but is inferior in heat resistance, transparency (after sterilization treatment), gloss (after sterilization treatment) and delamination strength (after sterilization treatment).

The laminate of the present invention can be used in the field of soft containers and food packaging in the medical field.

Claims (10)

A propylene-based resin layer mainly composed of the following component (A) is laminated on one side or both sides of an ethylene-based resin layer composed of 60 to 97% by weight of the following component (B) and 3 to 40% by weight of the following component (C). A laminate characterized by the above.
Component (A): Propylene / α-olefin random copolymer (A1) melt flow rate (MFR: 230 ° C., 21.18 N) polymerized using a metallocene catalyst and having the following characteristics (A1) to (A3) Load) is 0.1 to 50 g / 10 min.
(A2) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 1.5 to 3.5.
(A3) Melting peak temperature (Tm) measured by a differential thermal scanning calorimeter (DSC) is 121 to 150 ° C.
Component (B): Copolymer of ethylene and α-olefin having 3 to 12 carbon atoms having the following characteristics (B1) to (B2) (B1) Melt flow rate (MFR: 190 ° C., 21.18 N load) Is 0.1 to 20 g / 10 min.
(B2) The density is 0.880 to 0.930 g / cm ³ .
Component (C): High density polyethylene (C1) melt flow rate (MFR: 190 ° C., 21.18 N load) having the following characteristics (C1) to (C2): 0.1 to 50 g / 10 min.
(C2) density 0.940~0.980g / cm ^3. The layered product according to claim 1, wherein component (B) is a copolymer produced using a metallocene catalyst and having the following properties (B3) to (B4).
(B3) The content of α-olefin is 5 to 40% by weight.
(B4) The ratio (Mz / Mn) of the Z average molecular weight (Mz) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 8.0 or less. The laminate according to claim 1 or 2, wherein the component (A) is a copolymer having the following property (A4).
(A4) The relationship between the melting peak temperature (Tm) and the comonomer content (Ec) satisfies the following formula (1).
Tm ≧ −6.7049 × Ec + 140 (1)   The layered product according to any one of claims 1 to 3, wherein the component (A) is a propylene / ethylene random copolymer.   The laminate according to any one of claims 1 to 4, wherein the propylene-based resin layer is laminated on both sides of the ethylene-based resin layer.   The propylene-based resin layer is a composition containing 0.01 to 5 parts by weight of a nucleating agent with respect to 100 parts by weight of a propylene / α-olefin random copolymer. The laminate according to claim 1. The laminate according to claim 6, wherein the nucleating agent is a high-density polyethylene component (D) having the following properties (D1) to (D2).
(D1) Melt flow rate (MFR: 190 ° C., 21.18 N load) is 0.1 to 3000 g / 10 minutes.
(D2) Density is 0.940-0.980 g / cm ³ .   The thickness of the whole laminated body is 100-700 micrometers, The laminated body of any one of Claims 1-7 characterized by the above-mentioned.   The ratio of the propylene-type resin layer with respect to the whole thickness of a laminated body is 15 to 60%, The laminated body of any one of Claims 1-8 characterized by the above-mentioned. A medical bag comprising the laminate according to any one of claims 1 to 9.