JP2003237002A - Laminate and container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyethylene resin laminate which has excellent transparency, blocking resistance, flexibility and the like, a high heat resistance capable of sterilizing at 121°C and in which an impact strength of a sealed part is remarkably improved as compared with that of a prior art and to provide a medical container made of the same or a food container or the like. <P>SOLUTION: The container comprises the laminate having an inner layer and an outer layer made of a resin material containing a high-density polyethylene, an intermediate layer using a resin material containing a polyethylene resin I as a main body having a density of less than 0.920 g/cm<SP>3</SP>, an amount X (mass%) of a soluble content of an o-dichlorobenzene at an MFR of 0.1 to 50 g/10 min, 25°C, a density d (g/cm<SP>3</SP>) and an MFR (g/10 min) of X<9.8×10<SP>3</SP>×(0.9300-d+0.008logMFR)<SP>2</SP>+2.0, and a parameter Cb of a composition distribution of 1.08 to 2.00, so that the inner layer of the laminate is a heat sealing layer. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a container for medical use or a container for retort food, which is excellent in blocking resistance, transparency and flexibility and has a high impact strength of a seal portion and which can be filled with blood, drug solution and the like. To a suitable laminate and container. As medical containers, blood bags, platelet storage bags, infusion (medicine) bags, medical multi-chamber containers (two or more types of medicinal liquids are stored in separate storage chambers separated by an adhesive, and the adhesive is used at the time of use) And a plurality of pharmaceutical liquids are mixed in a sealed state by peeling off), an artificial dialysis bag, and the like.

[0002]

2. Description of the Related Art As a medical container filled with blood, drug solution, etc., transparency for facilitating confirmation of presence / absence of foreign substances and change due to drug formulation, heat resistance to withstand sterilization treatment, etc. The flexibility and the like for facilitating the discharge of the internal solution is required.

Conventionally, in medical containers or food containers for retorts which satisfy such performances, in addition to soft vinyl chloride, high-pressure process low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate Polyethylene-based and polypropylene-based materials such as polymers have been used. However, the ethylene / vinyl acetate copolymer has poor heat resistance, and the vinyl chloride resin has a problem that the plasticizer is eluted into the chemical solution. Polypropylene has poor flexibility, and high-pressure low-density polyethylene has inferior strength. Further, linear low density polyethylene needs to have a low density in order to satisfy transparency and flexibility, but if the density is lowered, the heat resistance tends to be insufficient, and the low molecular weight components of the resin, etc. bleed out. There was a problem such as doing.

Recently, a linear polyethylene material produced by a single-site catalyst having excellent impact resistance and transparency has been developed, and there is a movement to apply it to a medical container or a retort food container. Also, by combining them, 2
A method of stacking layers, 3 layers, etc. has also been proposed (JP-A-8-309939, JP-A-7-125738).
JP-A-8-244791, etc.).

However, even in these proposed laminates, the transparency is still insufficient, and the impact strength of the heat seal part is not sufficient, and the heat seal part is damaged when the bag is dropped. Therefore, improvement was desired. Further, when formed by a water-cooled inflation method or a T-die method, the surface of the obtained film or sheet becomes particularly smooth, the films or sheets block each other, and when peeled off, whitening scratches or the like occur on the surface, and the appearance Was sometimes significantly reduced. Currently 121
Demand for containers that can be sterilized at ° C is also increasing, and heat resistance is required more than ever.

[0006]

DISCLOSURE OF THE INVENTION The present invention is excellent in transparency, blocking resistance, flexibility and the like, and is 121 ° C.
It is an object of the present invention to provide a polyethylene-based resin laminate having high heat resistance capable of being sterilized and having a significantly improved impact strength of a seal portion as compared with a conventional one, and a medical container, a food container or the like made of the same.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventor has found that the above problems can be solved by forming a laminate comprising an inner layer, an intermediate layer and an outer layer made of a specific resin material. Heading, completed the present invention.

That is, the present invention is a laminate having at least an inner layer, an intermediate layer, and an outer layer, wherein the inner layer is made of a resin material (A) containing high-density polyethylene, and the intermediate layer is ethylene and has 3 carbon atoms. To an ethylene-α-olefin copolymer obtained by copolymerizing 20 to α-olefin, and a resin material (B) mainly comprising a polyethylene resin I having the following physical properties (a) to (d): And a resin material (C) in which the outer layer contains high-density polyethylene,
The present invention provides a laminated body comprising: and a medical container comprising the laminated body. (A) Density is less than 0.920 g / cm ³ (b) MFR is 0.1 to 50 g / 10 minutes (c) Amount X of o-dichlorobenzene-soluble component at 25 ° C. (% by mass) ) And density d (g / cm ³ ) and MFR (g /
10 minutes) satisfies the following relation X <9.8 × 10 ³ × (0.9300-d + 0.008)
logMFR) ² +2.0 (d) The composition distribution parameter Cb is 1.08 to 2.0.
Must be 0

Further, in the preferable laminate of the present invention, the resin material (A) constituting the inner layer is made of only high density polyethylene.

In the preferred laminate of the present invention, the resin material (A) constituting the inner layer is ethylene obtained by copolymerizing high density polyethylene with ethylene and an α-olefin having 3 to 20 carbon atoms. An α-olefin copolymer, which is a resin composition obtained by blending a polyethylene resin II having the following physical properties (e) to (h). (E) Density of 0.920 g / cm ³ or more 0.960 g /
less than cm ³ (f) MFR of 0.1 to 50 g / 10 minutes (g) amount of o-dichlorobenzene-soluble component at 25 ° C. X (mass%) and density d (g / cm ³ ) And MFR (g /
10 minutes) satisfy the following relationship: a) d-0.008logMFR ≧ 0.93, X <2.0 b) d-0.008logMFR <0.93, X <9.8 × 10 ³ × (0.9300-d + 0.008
logMFR) ² +2.0 (h) The composition distribution parameter Cb is less than 2.00.

In the preferred laminate of the present invention, the resin material (A) constituting the inner layer is ethylene obtained by copolymerizing high-density polyethylene with ethylene and an α-olefin having 3 to 20 carbon atoms. In the case of α-olefin copolymer, α-olefin is propylene, butene-1,
4-methylpentene-1, hexene-1, octene-
1 or 2 or more kinds selected from the group consisting of 1, decene-1 and dodecene-1.

The preferred laminate of the present invention is an ethylene / α-olefin copolymer constituting the polyethylene resin II, wherein the content of the α-olefin in the copolymer is 30 mol% or less. Is characterized in that.

In a preferred laminate of the present invention, the resin material (A) constituting the inner layer is 40 to 99 mass% of the high density polyethylene and the polyethylene resin II6.
The resin composition is characterized by being mixed with 0 to 1% by mass.

A preferred laminate of the present invention is the above tree.
The high density polyethylene of the fat material (A) has an MFR of 0.1.
~ 20g / 10 minutes, density 0.940-0.970g /
cm ³Is to have.

A preferred laminate of the present invention is characterized in that the resin material (B) constituting the intermediate layer is composed of the polyethylene resin I only.

In the preferred laminate of the present invention, when the intermediate layer is an ethylene / α-olefin copolymer obtained by copolymerizing ethylene with an α-olefin having 3 to 20 carbon atoms, the α-olefin is But propylene, butene-
It is characterized by being one or more selected from the group consisting of 1,4-methylpentene-1, hexene-1, octene-1, decene-1, and dodecene-1.

In a preferred laminate of the present invention, the polyethylene resin I satisfies the above physical properties (a) to (d) and has the following physical properties (i) and (j). Characterize. (I) Mw / Mn is 1.5 to 3.5 (j) Multiple peaks of elution temperature-elution amount curve by continuous temperature rising elution fractionation method (TREF) are present.

A preferred laminate of the present invention is characterized in that the resin material (B) constituting the intermediate layer is a resin composition prepared by mixing the polyethylene resin I and the polyethylene resin II. And

Further, in the preferable laminated body of the present invention, the resin material (B) constituting the intermediate layer is 50 to 99% by mass of the polyethylene resin I and the polyethylene resin II5.
The resin composition is characterized by being mixed with 0 to 1% by mass.

In a preferred laminate of the present invention, the resin material (B) constituting the intermediate layer is the polyethylene resin I, high density polyethylene, medium density polyethylene,
A resin composition comprising at least one selected from the group consisting of high-pressure low-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene random copolymer, and ethylene-propylene block copolymer. It is characterized by

Further, in the preferred laminate of the present invention, the resin material (B) constituting the intermediate layer is a resin composition comprising the polyethylene resin I and a resin having a density of 0.935 g / cm ³ or more. Is characterized by.

Further, a preferable laminate of the present invention is characterized in that the resin material (C) constituting the outer layer is composed of only high density polyethylene.

A preferred laminate of the present invention is characterized in that the resin material (C) constituting the outer layer is a resin composition prepared by blending high density polyethylene and the polyethylene resin II. To do.

Further, in a preferable laminate of the present invention, the resin material (C) constituting the outer layer comprises 95 to 5 mass% of the high density polyethylene and the polyethylene resin II5 to
The resin composition is characterized by being mixed with 95% by mass.

Further, in the preferred laminate of the present invention, the outer layer is made of a resin material (D) composed of a heat resistant resin material having a melting point peak temperature of 130 ° C. or higher measured by a differential scanning calorimeter (DSC). It is characterized by

In the preferred laminate of the present invention, the heat-resistant resin material constituting the resin material (D) is medium density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-propylene block copolymer, Ethylene-vinyl alcohol copolymer (EVO
H), polyamide such as 6-nylon and 6,6-nylon, polyester such as polyethylene terephthalate and polybutylene terephthalate, and a resin composition comprising at least one compound selected from the group consisting of To do.

The preferred laminate of the present invention is characterized in that the total thickness is 0.01 to 1 mm.

In the preferred laminate of the present invention, the thickness ratio of each layer is as follows: inner layer / intermediate layer / outer layer = 30 to 1/40 to 98.
/ 30 to 1 (total total is 100).

The preferred laminate of the present invention is a water-cooled coextrusion multilayer inflation molding method or coextrusion multilayer T method.
It is characterized by being obtained by a die molding method.

Further, the container of the present invention comprises any one of the above laminated bodies. A preferred container of the present invention is characterized in that at least a part of the inner layer of the laminate is heat-sealed as a heat-sealing layer.

A preferred container of the present invention is characterized in that the inner layers of the laminate are heat-sealed on four sides and heat-sealed on four sides to form a bag.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The laminate of the present invention comprises the following inner layers,
It has at least an intermediate layer and an outer layer. I. Inner layer The inner layer in the laminate of the present invention is made of a resin material (A) containing high-density polyethylene. The resin material (A) may be made of only high-density polyethylene, or may be a resin composition obtained by mixing high-density polyethylene and a polyethylene resin II having predetermined physical properties.

(1) High Density Polyethylene The high density polyethylene used in the inner layer is an ethylene homopolymer produced by a conventionally known method such as a slurry method, a solution method or a gas phase method, or ethylene and a carbon number of 3. To 12 copolymers with α-olefins and mixtures thereof, and specific α-olefins include propylene, butene-1,4-methylpentene-1, hexene-1, octene-1, decene-1. , Dodecene-1 and the like.

The MFR of high density polyethylene is generally less than 0.
It is about 1 to 20 g / 10 minutes, preferably 0.1 to
It is 10 g / 10 minutes. When the MFR is within this range, the melt tension of the composition is in an appropriate range, and film formation is easy. Density is generally 0.940~0.970g / cm ³
The degree, preferably 0.945 to 0.970 g / c
m is ^3. If the density is within this range, there is an advantage that heat resistance can be maintained.

(2) Polyethylene resin II The polyethylene resin II used in the present invention has the following physical properties (e) to (h). (E) Density The density of the polyethylene resin II is 0.920 g / c.
m ³ or more and less than 0.960 g / cm ³ . If the density is less than this range, blocking is not preferable. on the other hand,
If the density exceeds this range, flexibility is reduced, which is not preferable. A more preferable density range is 0.920 to 0.95
0 g / cm ³ , particularly preferable density range is 0.920 to
It is 0.945 g / cm ³ .

(F) MFR The polyethylene resin II has an MFR of 0.1 to 50 g.
/ 10 minutes. When the MFR is less than this range, the moldability is lowered, which is not preferable. On the other hand, if the MFR exceeds this range, the strength decreases, which is not preferable. A more preferable MFR range is 0.1 to 20 g / 10 minutes.

(G) ο-Dichlorobenzene soluble content at 25 ° C The polyethylene resin II is
- dichlorobenzene (hereinafter abbreviated as "ODCB") soluble matter of the amount X (% by weight) and the density d (g / cm ³⁾ and MFR
(G / 10 minutes) satisfies the predetermined relationship.

The ODCB-soluble matter at 25 ° C. is measured by the following method. 20 mL of 0.5 g sample
The sample is completely dissolved by heating at 135 ° C. for 2 hours in ODCB, and then cooled to 25 ° C. After leaving this solution at 25 ° C. overnight, it is filtered through a Teflon (registered trademark) filter, and the filtrate is collected. Using an infrared spectrometer for this filtrate, the asymmetric stretching vibration of methylene was measured at a wave number of 2925 cm.
Calculate the absorption peak area near ^-1 and calculate the sample concentration from the calibration curve prepared in advance. From this value, the ODCB-soluble component at 25 ° C can be determined.

The amount X (mass%) of the ODCB soluble component of the polyethylene resin II at 25 ° C. and the density d (g / c)
The relationship between m ³ ) and MFR (g / 10 minutes) is as follows. A) In the case of d-0.008logMFR ≧ 0.93,
X is less than 2% by mass, preferably less than 1% by mass. B) When d-0.008logMFR <0.93,
X <9.8 × 10 ³ × (0.9300-d + 0.008
logMFR) ² +2.0, preferably X <7.4 × 1
0 ³ × (0.9300-d + 0.008logMFR) ²
+1.0, more preferably X <5.6 × 10 ³ ×
^{(0.9300-d + 0.008logMFR) 2} +
It is to satisfy the relationship of 0.5. Here, the densities d and MFR on the right side of the above inequality mean values excluding the units, respectively. Therefore, the amount X (mass%) of the ODCB-soluble component at 25 ° C. is smaller than the value obtained by substituting only the numerical values of the density d and MFR of the polyethylene resin II into the formula on the right side of the above inequality. It is necessary.

The ODCB-soluble component at 25 ° C. is mainly a high branching component and a low molecular weight component contained in the polyethylene resin. This content is desirable because it causes a problem of hygiene and causes blocking of the inner surface of the molded product. The amount of ODCB solubles is affected by comonomer content and molecular weight. Therefore, it is necessary that the density, MFR, and the amount of ODCB-soluble components, which are these indices, satisfy the above-mentioned relationship, because the copolymerization component (α
-Olefin) is less unevenly distributed. In the present invention, it is preferable that the polyethylene-based resin II satisfies the above relationship regarding the ODCB-soluble content, since heat resistance, hygiene and blocking resistance will be good.

(H) Cb The polyethylene resin II has a composition distribution parameter Cb of less than 2.00. The method for measuring the parameter Cb of the composition distribution is as follows. That is,
O-dichlorobenzene with added antioxidant (ODCB)
Then, the sample is heated and melted at 135 ° C. so that the sample concentration becomes 0.2 mass%. This solution was added to diatomaceous earth (Celite 54
5) is transferred to a column packed and cooled to 25 ° C. at a rate of 0.1 ° C./min to deposit the sample on the surface of Celite.
Next, while applying ODCB to this column at a constant flow rate,
The column temperature is raised step by step to 5 ° C up to 130 ° C, and the sample is eluted and fractionated. Methanol is mixed with the eluate, the sample is reprecipitated, filtered and dried to obtain a fraction sample at each elution temperature. The mass fraction of the eluted sample at each temperature and its branching degree (the number of branches per 1000 carbons) are measured by an isotope carbon nuclear magnetic resonance apparatus ( ¹³ C-NMR).

The following correction of the degree of branching is carried out for the fraction of 30 ° C to 90 ° C. That is, the measured branching degree is plotted against the elution temperature, and the correlation is approximated to a straight line by the method of least squares to create a calibration curve. The correlation coefficient of this approximation is sufficiently large. The value obtained from this calibration curve is the branching degree of each fraction. Since a linear relationship between the elution temperature and the degree of branching does not always hold for components with an elution temperature of 95 ° C. or higher, this correction is not performed and the measured value is used.

Next, the mass fraction w _i of each fraction is calculated by the change amount (b _i) of the branching degree b _i per elution temperature of 5 ° C.
-B _{i -1} ) to obtain the relative concentration C _i , plot the relative concentration against the branching degree, and obtain a composition distribution curve. This composition distribution curve is divided with a constant width, and the composition distribution parameter Cb is calculated from the following equation.

[0044]

[Equation 1]

Here, C _j and b _j are the relative density and branching degree of the j-th section, respectively. Composition distribution parameter Cb
Is 1.0 when the composition of the sample is uniform, and increases as the composition distribution spreads.

The composition distribution parameter Cb of the polyethylene resin II used in the present invention is less than 2.00, preferably in the range of 1.04 to 2.00. Cb
Of 2.00 or more results in poor blocking resistance and poor heat seal properties. In addition, bleed-out of low molecular weight components and the like to the resin surface is likely to occur, which causes a problem in hygiene.

Examples of the polyethylene resin II include
Examples thereof include ethylene / α-olefin copolymers. α-
The olefin has 3 to 20 carbon atoms, preferably 3 to 12 carbon atoms. Specific examples include propylene, butene-1,4-methylpentene-1, hexene-1, octene-1, decene-1, dodecene-1 and the like,
One or more of these can be used.
The content of these α-olefins in the copolymer is usually 30 mol% or less, preferably 20 mol% or less.

Method for producing polyethylene resin II The method for producing polyethylene resin II is not particularly limited,
Any method produced by any method can be used as long as it satisfies the above physical properties, but it is preferably a group IV group of the periodic table containing 0, 1, or 2 ligands having a cyclopentadienyl skeleton. The one obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms in the presence of a catalyst containing the above transition metal compound as an essential component is used. More preferably, the polyethylene resin II
Is produced by the catalyst shown below, but is not limited to the following. For example, a cyclopentadienyl derivative having a transition metal selected from Group IV of the periodic law is
A catalyst system comprising an organic transition catalyst containing one, two, or one and a compound that reacts with the organic transition catalyst to form an ionic complex and / or an organoaluminumoxy compound. If necessary, an organoaluminum compound may be used in the catalyst system. Further, the organic transition catalyst can be used by supporting it on an inorganic compound, fine particles or the like, if necessary.

For example, JP-A-11-293054 and JP-A-11-31
It can be produced using the catalysts disclosed in the publications such as 0607, JP-A-8-309939 and JP-A-10-77370.
However, it is not limited to these.

(3) Resin Material (A) The resin material (A) contains the above-mentioned high-density polyethylene, and may be composed of only the high-density polyethylene. It may be a resin composition with Resin II.

In the case of the resin composition, the high density polyethylene and the polyethylene resin II in the resin material (A) are used.
The blending ratio with is 40 to 99 mass% of high-density polyethylene, preferably 50 to 99 mass%, and more preferably 60.
˜99% by mass. If the blending ratio of the high-density polyethylene is less than the above range, the impact strength of the seal portion is lowered, which is not preferable. On the other hand, if the blending ratio exceeds the above range, the strength decreases, which is not preferable.

In particular, in the present invention, when the inner layer is made of a resin material containing 50 mass% or more of high-density polyethylene as a main component, the above-mentioned physical properties (e) to ( The heat resistance is improved and the heat sealing property, particularly, the impact strength of the seal portion is significantly improved, as compared with the case where the resin material is mainly composed of the ethylene / α-olefin copolymer having h).

In the resin material (A), known additives that are usually used, such as an antistatic agent, an antioxidant, a lubricant, and the like, are used as long as the effects of the present invention are not significantly impaired.
An anti-blocking agent, an anti-fogging agent, an organic or inorganic pigment, an ultraviolet absorber, a dispersant, etc. can be appropriately added as necessary.

II. Intermediate Layer The intermediate layer in the laminate of the invention has the following physical properties (a) to
It is composed of a resin material (B) mainly composed of a polyethylene resin I provided with (d).

(1) Polyethylene resin I (a) Density The density of the polyethylene resin I is 0.920 g / cm.
It is less than ³ . When the density exceeds this range, transparency and flexibility are deteriorated, which is not preferable. A more preferable density range is 0.880 to 0.920 g / cm ³ , and a particularly preferable density range is 0.890 to 0.918 g / cm ³ .

(B) MFR The polyethylene resin I has an MFR of 0.1 to 50 g /
10 minutes. When the MFR is less than this range, the moldability is lowered, which is not preferable. On the other hand, if the MFR exceeds this range, the strength decreases, which is not preferable. More preferable M
The range of FR is 0.1 to 10 g / 10 minutes.

(C) ODCB Soluble Content The polyethylene resin I has an OD at 25 ° C.
The amount X (mass%) of the CB soluble component, the density d and the MFR satisfy a predetermined relationship. Where O at 25 ° C
The DCB soluble content can be determined by the above-mentioned measurement method. O of the polyethylene resin I at 25 ° C.
DCB soluble content X (mass%) and density d (g / cm ³ )
And the relationship between MFR (g / 10 minutes) are as follows. X <9.8 × 10 ³ × (0.9300-d + 0.008
logMFR) ² +2.0, preferably X <7.4 × 1
0 ³ × (0.9300-d + 0.008logMFR) ²
+1.0, more preferably X <5.6 × 10 ³ ×
^{(0.9300-d + 0.008logMFR) 2} +
It is to satisfy the relationship of 0.5. Here, the densities d and MFR on the right side of the above inequality mean values excluding the units, respectively. Therefore, the amount X (mass%) of the ODCB soluble component at 25 ° C. is smaller than the value obtained by substituting only the numerical values of the density d and MFR of the polyethylene resin I into the formula on the right side of the above inequality. It is necessary.
In the present invention, the polyethylene resin I is ODCB.
Satisfying the above relationship regarding the soluble content is preferable because heat resistance, hygiene and blocking resistance are improved.

(D) Cb The polyethylene resin I has a composition distribution parameter Cb of less than 2.00, preferably 1.08 to
The range is 2.00. When Cb is within the above range, there is an advantage that the blocking resistance and the heat sealing property are excellent. On the other hand, when Cb is 2.00 or more, the blocking resistance is poor and the heat sealing property is also poor. In addition, bleed-out of low molecular weight components and the like to the resin surface is likely to occur, which causes a problem in hygiene. The method of measuring the parameter Cb of the composition distribution is as described above.

Examples of the polyethylene resin I include ethylene / α-olefin copolymers. The α-olefin has 3 to 20 carbon atoms, preferably 3 to 12 carbon atoms. Specific examples include propylene, butene-1,4-methylpentene-1, hexene-1, octene-1, decene-1, dodecene-1, and the like, and it is possible to use one or more of these. it can. The content of these α-olefins in the copolymer is usually 30 mol% or less, preferably 20 mol% or less.

(2) Preferred Polyethylene Resin I More preferably, the polyethylene resin I used in the present invention satisfies the above physical properties (a) to (d),
Further, those satisfying the following physical properties (i) and (j) can be mentioned.

(I) Mw / Mn The preferred polyethylene resin I of the present invention has a molecular weight distribution (Mw / Mn) of 1.5-3.5, preferably 2.0-.
It is 3.0. Here, the calculation method of Mw / Mn is to obtain the weight average molecular weight (Mw) and the number average molecular weight (Mn) by gel permeation chromatography (GPC), and obtain the ratio Mw / Mn. Mw / Mn
Is less than the above range, the moldability is poor, and if it exceeds the above range, the impact resistance is poor.

(J) Peak of elution temperature-elution amount curve by TREF The preferred polyethylene resin I of the present invention has a plurality of peaks of elution temperature-elution amount curve by the continuous temperature rising elution fractionation method (TREF). It is a thing. More preferably, at least one of the peaks is 85 to 100 ° C.
Is particularly preferably present between The presence of this peak improves the heat resistance of the molded body.

Here, the method of measuring TREF is as follows. The sample is heated and dissolved at 135 ° C. in ODCB containing an antioxidant so that the sample concentration becomes 0.05% by mass. 5 mL of this sample solution is injected into a column filled with glass beads and cooled to 25 ° C. at a cooling rate of 0.1 ° C./min to deposit the sample on the surface of the glass beads. Next, the column temperature is raised at a constant rate of 50 ° C./hr while flowing ODCB at a constant flow rate through this column, and the sample is sequentially eluted. At this time, as for the concentration of the sample eluted in the solvent, the absorption at a wave number of 2925 cm ⁻¹ of the asymmetric stretching vibration of methylene is continuously measured by an infrared spectrometer. From this value, the concentration of the ethylene / α-olefin copolymer in the solution is quantitatively analyzed to determine the relationship between the elution temperature and the elution rate. Since the TREF analysis can continuously analyze the change in the elution rate with respect to the temperature change with an extremely small amount of sample, it is possible to detect relatively fine peaks that cannot be detected by the fractionation method.

(3) Method for producing polyethylene resin I The method for producing the polyethylene resin I is not particularly limited, and any method can be used as long as it satisfies the above physical properties, but is preferably used. Ethylene and α-C 3-20 in the presence of a catalyst containing as an essential component a transition metal compound of Group IV of the periodic table containing 0, 1, or 2 ligands having a cyclopentadienyl skeleton. The thing obtained by copolymerizing with an olefin is used.

More preferably, the polyethylene resin I is produced by the catalyst shown below, but is not limited to the following. For example, a cyclopentaenyl derivative having a transition metal selected from Group IV of the periodic law is
A catalyst system comprising an organic transition catalyst containing one, two, or one and a compound that reacts with the organic transition catalyst to form an ionic complex and / or an organoaluminumoxy compound. If necessary, an organoaluminum compound may be used in the catalyst system. Further, the organic transition catalyst can be used by supporting it on an inorganic compound, fine particles or the like, if necessary. For example, it can be produced using the catalyst disclosed in the above publication. However, it is not limited to this.

As the polymerization method, a gas phase method, a slurry method,
Any method such as a solution method may be used, and a one-step polymerization method or a multi-step polymerization method may be used.

(4) Resin Material (B) The resin material (B) is mainly composed of the polyethylene resin I, and is preferably composed of the polyethylene resin I only, but does not impair the effects of the present invention. Resins other than the polyethylene resin I may be blended in the range. Examples of such other resins include polyethylene resin II, high-density polyethylene, medium-density polyethylene, high-pressure low-density polyethylene, linear low-density polyethylene,
Examples thereof include polypropylene, ethylene-propylene random copolymer, ethylene-propylene block copolymer and the like. If other resins are blended, polyethylene resin I
It is desirable that the ratio is 50 mass% or more, preferably 60 mass% or more. The ratio of polyethylene resin I is 5
If it is less than 0% by mass, the strength is lowered, which is not preferable. Among other resins, the density is 0.935 g / cm ³ or more,
A resin of 0.940 g / cm ³ or more is preferable because the heat resistance of the laminate is improved, and specific examples of such a resin are selected from polyethylene-based resin II, linear low-density polyethylene and high-density polyethylene. Density 0.
Examples of the resin include 935 g / cm ³ or more, and high density polyethylene is particularly preferable.

In the resin material (B), known additives usually used, such as an antistatic agent, an antioxidant, a lubricant, an antiblocking agent, an antifogging agent, are added to the extent that the effects of the present invention are not significantly impaired. Organic or inorganic pigments,
An ultraviolet absorber, a dispersant and the like can be appropriately added as needed.

III. Outer Layer The outer layer in the laminate of the present invention is made of a resin material (C) containing high-density polyethylene. The resin material (C) may be made of only high density polyethylene,
It may be a resin composition obtained by blending the high-density polyethylene with the above-mentioned polyethylene resin II and / or high-pressure low-density polyethylene. The high-density polyethylene and the polyethylene-based resin II can be selected from the resins that can be used as the high-density polyethylene and the polyethylene-based resin II that form the inner layer described above.

When a resin composition composed of the high density polyethylene and the polyethylene resin II is used as the outer layer, the mixing ratio thereof is polyethylene resin II5.
The content is 95% by mass, preferably 15 to 85% by mass, more preferably 30 to 70% by mass. Polyethylene resin II
If the blending ratio is less than the above range, the strength decreases, which is not preferable. On the other hand, if the blending ratio exceeds the above range, blocking occurs, which is not preferable. When a resin composition comprising the high-density polyethylene and the high-pressure low-density polyethylene is used as the outer layer, the compounding ratio thereof is 5-95 mass% of the high-pressure low-density polyethylene, preferably 15-8.
It is 5% by mass, more preferably 30 to 75% by mass. When the blending ratio of the high-pressure low-density polyethylene is within the above range, the moldability is improved, and defective appearance such as wrinkles is less likely to occur, and an excellent appearance can be obtained.

The outer layer is also a differential scanning calorimeter (DS).
It may be composed of a heat-resistant resin material (D) having a melting point peak temperature of 130 ° C. or higher measured in C). If there are multiple peaks, the highest temperature peak is 1
It shows 30 ° C. or higher. Examples of the resin material (D) include medium density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-propylene block copolymer, ethylene / vinyl alcohol copolymer (EVOH), 6-nylon and 6,6- Examples thereof include polyamides such as nylon, polyesters such as polyethylene terephthalate and polybutylene terephthalate.

To the resin materials (C) and (D) constituting the outer layer, known additives usually used, such as antistatic agents, antioxidants, lubricants, etc., are added, so long as the effects of the present invention are not significantly impaired. An anti-blocking agent, an anti-fogging agent, an organic or inorganic pigment, an ultraviolet absorber, a dispersant, etc. can be appropriately added as necessary.

IV. Laminate (1) Layer Structure The laminate of the present invention is not particularly limited as to the other layer structure as long as it has an inner layer, an intermediate layer, and an outer layer (the inner layer is a heat seal layer) in this order. For the number of layers,
The three layers consisting of the outer layer / intermediate layer / inner layer are most preferable, but not limited thereto. Outer layer / intermediate layer / outer layer in which an intermediate layer in the inner layer is further constituted / intermediate layer / most intermediate layer / intermediate layer / If necessary, another layer may be provided between the outer layer and the intermediate layer, or between the intermediate layer and the inner layer. Examples of such other layer include an adhesive layer, a gas barrier layer, and an ultraviolet absorbing layer. For example, 5 outer layer / gas barrier layer / intermediate layer / adhesive layer / inner layer
It can also have a layered structure. In addition, a layer can be newly provided outside the outer layer.

As the adhesive constituting the adhesive layer,
Examples of the adhesive resin include polyurethane adhesives, vinyl acetate adhesives, hot melt adhesives, maleic anhydride-modified polyolefins, and ionomer resins. When an adhesive layer is included in the layer structure, essential layers such as an inner layer and an intermediate layer can be laminated by coextrusion with these adhesives.

The most preferable layer structure of the present invention is inner layer / intermediate layer / outer layer = high density polyethylene / polyethylene resin I having the above physical properties (a) to (d) and (i) and (j). A resin composition / high density polyethylene obtained by blending a polyethylene resin II having the above physical properties (e) to (h) and a polyethylene resin II having the above physical properties (e) to (h) are blended. A resin composition comprising:

By taking such a layer structure, surprisingly, the heat resistance and the impact strength of the seal portion are remarkably improved. This is an effect particularly exhibited when this specific layer structure is taken, and when the polyethylene resin II having the above physical properties (e) to (h) is used alone as the resin material forming the inner layer. Can't be obtained. The reason why such effects are exhibited is not always clear, but the physical properties (strength) of not only the inner layer but also the intermediate layer and, in some cases, the outer layer.
However, it is thought that this affects the strength of the seal portion when the inner layers are heat-sealed. The advantages obtained by the combination of the layers made of such a specific resin material have not been described or suggested in the prior art.

(2) Thickness of Each Layer The total thickness of the laminate in the present invention is not particularly limited and can be appropriately determined as necessary, but is preferably 0.01 to 1 mm, more preferably 0.1 to 1. 0.5 mm
Is. When the total thickness is within the above range, there is an advantage that the transparency and flexibility are excellent.

The thickness ratio of each layer is not particularly limited, but it is preferable that the low density layer (intermediate layer) using a resin material having a density of 0.920 g / cm ³ or less be the main center layer in terms of thickness. preferable. More preferably, inner layer: middle layer: outer layer = 1 to 30:40 to 98: 1 to 30 (thickness ratio)
The degree is good (however, the total sum is 100).

(3) Method for producing laminated body The method for producing the laminated body of the present invention is not particularly limited, but a water-cooled or air-cooled coextrusion multilayer inflation method, a coextrusion multilayer T-die method, a dry lamination method, an extrusion lamination method. A method of forming a laminated film or sheet by the above method can be used. Among these, it is preferable to use the water-cooled coextrusion multilayer inflation molding method or the coextrusion multilayer T die molding method. In particular, when a water-cooled coextrusion multilayer inflation molding method is used, there are many advantages in terms of transparency and hygiene. Alternatively, a multi-layer hollow molding method may be used to form a multi-layer hollow molding product.

In the case of a laminated film or sheet, it can be further processed into a bag shape by heat sealing, and the one obtained by multilayer hollow molding can be used as it is or as a container with a plug or the like attached thereto. In particular, as the laminate of the present invention, a bag-like laminate in which at least a part of the film- or sheet-like laminate is heat-sealed with the inner layer being a heat-sealing layer is preferable.

V. Uses The laminate of the present invention has an impact strength of 700 kJ / m ² when the inner layer is heat-sealed as a heat-sealing layer and processed into a bag shape, for example, when the heat-sealing portion is sealed at a temperature of 155 ° C. Above, further 800 kJ / m ²
As described above, those having a high value such as 900 kJ / m ² or more can be obtained. Further, the laminated body of the present invention can maintain high impact strength of the seal portion even after heat treatment such as sterilization treatment necessary for medical containers, food containers and the like is performed. That is, for example, when sterilization treatment (121 ° C., 20 minutes) is performed, the impact strength of the seal portion after the sterilization treatment is, for example, 500 kJ / m ² or more, further 600 kJ / m ² or more, particularly 700 kJ / m ² or more. Those with very high values are obtained. The impact strength of the seal part here is
It is a value when heat sealing is performed under the conditions of a sealing temperature of 155 ° C., a sealing time of 5 seconds, and a sealing pressure of 0.4 MPa as heat sealing conditions.

As described above, the container made of the laminated body of the present invention can maintain a high strength of the seal portion even after the heat treatment such as the sterilization treatment. Therefore, it is suitable for a medical container, a food container such as a retort bag, which requires a high seal strength even after sterilization. In particular, medical containers such as medical infusion bags, such as blood bags, platelet storage bags, infusion (medicine) bags, medical multi-chamber containers (separate storage of two or more medicinal liquids separated by an adhesive part) It can be suitably used for artificial dialysis bags, etc. by storing it in a chamber and peeling off the adhesive portion at the time of use to mix the plurality of pharmaceutical liquids in a sealed state.

[0083]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. In addition, the physical-property evaluation method in the following Examples and Comparative Examples is as follows. (1) MFR; measured according to JIS-K6760. (2) Density; measured according to JIS-K6760.

(3) 0.5 g of ODCB soluble matter sample was heated in 20 mL of ODCB at 135 ° C. for 2 hours to completely dissolve the sample, and then cooled to 25 ° C. This solution was allowed to stand overnight at 25 ° C., filtered through a Teflon filter, and the filtrate was collected. For this filtrate, using an infrared spectrometer, the wave number 2 which is the asymmetric stretching vibration of methylene
The absorption peak area near 925 cm ⁻¹ was obtained, and the sample concentration was calculated from the calibration curve prepared in advance. From this value, the ODCB soluble content at 25 ° C was determined.

(4) Cb An antioxidant (2,6, -Di-t-Butyl-p-Cresol, 0.1%) was added to o-dichlorobenzene (ODCB) at a sample concentration of 0.2% by mass. The sample was heated and melted at 135 ° C. This solution was transferred to a column packed with diatomaceous earth (Celite 545) and cooled to 25 ° C at a rate of 0.1 ° C / minute to deposit a sample on the surface of Celite. Next, while flowing ODCB at 1 mL / min through this column, the column temperature was raised stepwise at 5 ° C. to 120 ° C., and the sample was eluted and fractionated. Methanol was mixed with the eluate, the sample was reprecipitated, filtered and dried to obtain fraction samples at each elution temperature. The weight fraction of the eluted sample at each temperature and its degree of branching (number of branches per 1000 carbons) were determined to be ¹³ C.
-Measured by NMR. Then, the weight fraction w _i of each fraction to obtain the relative concentration C _i divided by the amount of change in the degree of branching b _i per the elution temperature _{5 ℃ (b i -b i-} 1), with respect to the degree of branching Then, the relative concentration was plotted to obtain a composition distribution curve. This composition distribution curve was divided into a certain width, and the composition distribution parameter Cb was calculated from the above formula.

(5) Mw / Mn The weight average molecular weight (Mw) and number average molecular weight (Mn) were determined by gel permeation chromatography (GPC) (by a calibration curve method using PS standard sample), and the ratio M
The w / Mn was calculated. The detailed conditions are as follows. GPC; Waters, 150 type eluent; ODCB column temperature; 135 ° C column; Tosoh Corp. GMMHR-H (S)

(6) Number of TREF peaks ODCB containing an antioxidant (2,6, -Di-t-Butyl-p-Cresol, 0.1%) was added to a sample concentration of 0.05% by mass.
The sample was heated and melted at 5 ° C. 5 mL of this sample solution was injected into a column filled with glass beads and cooled to 25 ° C. at a cooling rate of 0.1 ° C./min to deposit the sample on the surface of the glass beads. Next, add 1 mL / ODCB to this column.
While flowing in minutes, the column temperature was raised at a constant rate of 50 ° C./hr to elute the samples sequentially. At this time, the concentration of the sample eluted in the solvent was continuously measured by an infrared spectrometer for absorption at a wave number of 2925 cm ⁻¹ of the asymmetric stretching vibration of methylene. A cross fractionation chromatograph (manufactured by Mitsubishi Chemical Corporation) was used as a measuring device. From this value, the concentration of the ethylene / α-olefin copolymer in the solution was quantitatively analyzed to determine the relationship between the elution temperature and the elution rate. Then, an elution temperature-elution amount curve was prepared and the number of peaks was counted.

(7) Impact strength of seal portion The inner layer is used as a heat seal layer, pressure is 0.4 MPa, and the seal is
Heat sealing was performed at a temperature of 155 ° C. and a seal time of 5 seconds.
The s-type test shape used in the tensile impact test method (ASTM-D1822) was punched so that the seal interface of the seal portion was at the center. Sterilization (121
After 20 minutes at ℃, open in a T-shape at the boundary of the seal, 23
It was measured with a tensile impact tester at ° C.

(8) Blocking resistance Two films each having a length of 5 cm cut into strips having a width of 20 mm were stacked, and a weight of 10 kg was placed on the film. The film was allowed to stand in an oven kept at 50 ° C. for 48 hours and then at 23 ° C. Adjust the condition with 2
The sheet of film was peeled off, and the peeled surface was visually observed. ○: The surface is not whitened ×: The surface is whitened

(9) Heat resistance A film having a length of 20 cm and a width of 20 cm was cut, sealed on three sides, water was poured into the inside, and the remaining one was sealed to form a four-side sealed water bag. And 121 ℃, 20
After the sterilization treatment for minutes, the appearance was visually evaluated. ⊚: No deformation or wrinkles ◯: No deformation, but some wrinkles ×: Deformed and many wrinkles

Examples 1 to 12 and Comparative Examples 1 to 3 Laminated films consisting of the inner layer, the intermediate layer and the outer layer made of the resins shown in Table 1 were produced by water-cooling type coextrusion multilayer inflation molding. The thickness of each layer was 10 μm / 225 μm / 15 μm from the inner layer side. Table 2 shows the measurement results of heat resistance, blocking resistance, and impact strength of the seal portion.

The resins used in the examples and comparative examples are described below. (1) s-LL1; ethylene-hexene-1 copolymer using a single-site catalyst (density: 0.898 g / c
m ³ , MFR: 1.0 g / 10 min, Mw / Mn: 2.7) (2) s-LL2; ethylene / hexene-1 copolymer using a single-site catalyst (density: 0.905 g / c
m ³ , MFR: 1.2 g / 10 minutes, Mw / Mn: 2.
8) (3) s-LL3; ethylene-hexene-1 copolymer using a single-site catalyst (density: 0.901 g / c
m ^3, MFR: 0.8g / 10 min, Mw / Mn; 2.
3) (4) s-LL4; ethylene-hexene-1 copolymer using a single-site catalyst (density: 0.924 g / c
m ³ , MFR: 2.1 g / 10 minutes, Mw / Mn: 2.
6) (5) s-LL5; ethylene-hexene-1 copolymer using a single-site catalyst (density: 0.942 g / c
m ³ , MFR: 1.2 g / 10 minutes, Mw / Mn: 2.
2) (6) HD1; high-density polyethylene (density: 0.945
g / cm ³ , MFR: 2.8 g / 10 minutes) (7) HD2; high density polyethylene (density: 0.952
g / cm ³ , MFR: 3.5 g / 10 min) (8) LD1; high pressure method low density polyethylene (density: 0.
927 g / cm ³ , MFR: 1.5 g / 10 minutes) (9) PP1; propylene / ethylene random copolymer (density: 0.900 g / cm ³ , MFR: 4.0 g / 1
0 minutes) (10) PP2; propylene / ethylene block copolymer (density: 0.900 g / cm ³ , MFR: 2.5 g /
10 minutes)

[0093]

[Table 1]

[0094]

[Table 2]

[0095]

As described above, the laminated body of the present invention can maintain a high seal strength even after heat treatment such as sterilization. Therefore, it is suitable for a medical container, a food container such as a retort bag, which requires a high seal strength even after sterilization. In particular, medical containers such as medical infusion bags, such as blood bags, platelet storage bags, infusion (medicine) bags, medical multi-chamber containers (separate storage of two or more medicinal liquids separated by an adhesive part) It is stored in a room, and the plurality of medicinal liquids are mixed in a sealed state by peeling off the adhesive portion at the time of use), and it can be preferably used for artificial dialysis bags and the like.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B65D 30/22 B65D 30/22 G 65/40 65/40 D 81/32 81/32 D // B29K 23:00 B29K 23:00 B29L 9:00 B29L 9:00 22:00 22:00 (72) Inventor Tomohiko Ezaki 3-2 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Akira Kawasaki Laboratory (72) Inventor Akihiko Sakata 3-2 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Sho Denko Plastic Products Co., Ltd. Kawasaki Laboratory (72) Isao Otake 3-2 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Sho Denko Plastic Products Co., Ltd. Kawasaki laboratory F-term (reference) 3E064 AA05 BA24 BA36 BA54 BB03 BC01 BC13 BC18 BC20 EA07 FA04 HN05 HT07 3E086 AA23 AB02 AC07 AC22 AD01 BA04 BA15 BB41 BB51 BB58 BB85 CA01 CA27 DA08 4F100 AK05A AK05C AK06B AK06C AK42C AK46C AK48C AK62A AK62B AK62C AK64A AK64B AK64C AK65A AK65B AK65C AK 68C AL02B AL02C AL05A AL05C BA10A BA10C DA01 EH20 GB16 GB23 GB66 JA04C JA06A JA06B JA07C JA13A JA13B JC00 JJ03C JK10 JK17 JL00 JN01 4F207 AA03E AA04C AA05 AG03 AG07 AR15 AR17 AR18

Claims (26)

[Claims] 1. A laminate having at least an inner layer, an intermediate layer, and an outer layer, wherein the inner layer is made of a resin material (A) containing high-density polyethylene, and the intermediate layer is ethylene and α- having 3 to 20 carbon atoms. An ethylene / α-olefin copolymer obtained by copolymerizing an olefin with the following physical properties (a)
To (d), which is made of a resin material (B) containing polyethylene resin I as a main component, and wherein the outer layer is made of a resin material (C) containing high-density polyethylene. (A) Density is less than 0.920 g / cm ³ (b) MFR is 0.1 to 50 g / 10 minutes (c) Amount X of o-dichlorobenzene-soluble component at 25 ° C. (% by mass) ) And density d (g / cm ³ ) and MFR (g /
10 minutes) satisfies the following relation X <9.8 × 10 ³ × (0.9300-d + 0.008)
logMFR) ² +2.0 (d) The composition distribution parameter Cb is 1.08 to 2.0.
Must be 0 2. The resin material (A) forming the inner layer is made of only high density polyethylene.
The laminated body according to. 3. The resin material (A) constituting the inner layer is high-density polyethylene, ethylene and α-containing 3 to 20 carbon atoms.
An ethylene / α-olefin copolymer obtained by copolymerizing with an olefin, which is a resin composition obtained by blending a polyethylene resin II having the following physical properties (e) to (h). The laminated body according to claim 1. (E) Density of 0.920 g / cm ³ or more 0.960 g /
less than cm ³ (f) MFR of 0.1 to 50 g / 10 minutes (g) amount of o-dichlorobenzene-soluble component at 25 ° C. X (mass%) and density d (g / cm ³ ) And MFR (g /
10 minutes) satisfy the following relationship: a) d-0.008logMFR ≧ 0.93, X <2.0 b) d-0.008logMFR <0.93, X <9.8 × 10 ³ × (0.9300-d + 0.008
logMFR) ² +2.0 (h) The composition distribution parameter Cb is less than 2.00. 4. The α-olefin of claim 3 is propylene, butene-1,4-methylpentene-1, hexene-.
The laminate according to claim 3, which is one or more selected from the group consisting of 1, octene-1, decene-1, and dodecene-1. 5. The ethylene / α-olefin copolymer constituting the polyethylene resin II, wherein the content of the α-olefin in the copolymer is 30 mol% or less. Item 3. A laminate according to item 3. 6. The resin material (A) constituting the inner layer is a resin composition obtained by mixing 40 to 99% by mass of the high density polyethylene and 60 to 1% by mass of the polyethylene resin II. The laminated body according to claim 3, which is characterized in that. 7. The high-density polyethylene of the resin material (A) constituting the inner layer has an MFR of 0.1 to 20 g / 10 minutes,
The laminate according to claim 1, having a density of 0.940 to 0.970 g / cm ³ . 8. The laminate according to claim 1, wherein the resin material (B) constituting the intermediate layer is composed of the polyethylene resin I only. 9. The α-olefin according to claim 1 is selected from the group consisting of propylene, butene-1,4-methylpentene-1, hexene-1, octene-1, decene-1, and dodecene-1. It is 1 type or 2 or more types, The laminated body in any one of Claims 1-7 characterized by the above-mentioned. 10. The polyethylene resin I according to claim 1.
Satisfies the physical properties (a) to (d) and has the following physical properties (i) and (j).
The laminated body according to any one of to 7. (I) Mw / Mn is 1.5 to 3.5 (j) Multiple peaks of elution temperature-elution amount curve by continuous temperature rising elution fractionation method (TREF) are present. 11. A resin material (B) constituting the intermediate layer comprises the polyethylene resin I and the polyethylene resin I.
It is a resin composition which mix | blends with I, The laminated body in any one of Claims 1-7 characterized by the above-mentioned. 12. A resin composition (B) constituting an intermediate layer is a resin composition comprising 50 to 99% by mass of the polyethylene resin I and 50 to 1% by mass of the polyethylene resin II. Claims 1-7 and 9- characterized
11. The laminated body according to any one of 11. 13. A resin material (B) constituting the intermediate layer
However, the polyethylene resin I, high density polyethylene, medium density polyethylene, high pressure method low density polyethylene,
A resin composition comprising at least one selected from the group consisting of linear low-density polyethylene, polypropylene, an ethylene-propylene random copolymer, and an ethylene-propylene block copolymer. Item 8. A laminate according to any one of items 1 to 7. 14. A resin material (B) constituting the intermediate layer
Of the polyethylene resin I and the density of 0.935 g /
It is a resin composition with a resin of ³ or more cm3, The laminated body in any one of Claims 1-7 and 11-13. 15. The laminate according to claim 1, wherein the resin material (C) forming the outer layer is made of only high density polyethylene. 16. A resin material (C) constituting the outer layer,
15. A laminate according to any one of claims 1 to 14, which is a resin composition obtained by mixing high-density polyethylene with the polyethylene-based resin II according to claim 3. 17. A resin material (C) constituting the outer layer,
A resin composition comprising a mixture of high-density polyethylene and high-pressure low-density polyethylene.
The laminated body according to any one of to 14. 18. A resin material (C) constituting the outer layer,
It is a resin composition which mix | blends the said high density polyethylene 95-5 mass% and the said polyethylene resin II 5-95 mass%, The laminated body in any one of Claims 1-14 characterized by the above-mentioned. 19. The outer layer is made of a resin material (D) composed of a heat-resistant resin material having a melting point peak temperature of 130 ° C. or higher measured by a differential scanning calorimeter (DSC). ~ 14 or the laminated body according to any one of claims 17 to 18. 20. The heat resistant resin material constituting the resin material (D) is a medium density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-propylene block copolymer, ethylene-vinyl alcohol copolymer ( EVOH), polyamide such as 6-nylon or 6,6-nylon, polyester such as polyethylene terephthalate and polybutylene terephthalate, and a resin composition containing at least one selected from the group consisting of The laminated body according to claim 19. 21. The laminate according to claim 1, wherein the total thickness is 0.01 to 1 mm. 22. The thickness ratio of each layer is such that inner layer / middle layer / outer layer =
30-1 / 40-98 / 30-1 (total of 100
And)), The laminated body according to any one of claims 1 to 21. 23. A water-cooled coextrusion multilayer inflation molding method or a coextrusion multilayer T die molding method.
A method for producing a laminated body, comprising obtaining the laminated body according to any one of 1. 24. A container comprising the laminate according to any one of claims 1 to 22. 25. The container according to claim 24, wherein at least a part of the inner layer of the laminate is heat-sealed as a heat-sealing layer. 26. The container according to claim 24, wherein the inner layers of the laminate are heat-sealed on four sides and heat-sealed on four sides to be processed into a bag shape.