JPH01168424A - Manufacture of large capacity vessel with gas barrier properties - Google Patents

Abstract

PURPOSE:To obtain the large capacity vessel excellent in gas barrier properties by a method in which the kneaded molten material of a specified resin composition is once accumulated in the accumulating mechanism provided in a die, and the discharging pressure of the resin from a die slit is always kept in a certain range. CONSTITUTION:The composition A containing the copolymer of polyolefin and ethylene vinylalhohol or linear polyamide in the weight ratio of 99:1-75:25, or the composition B containing 0.5-20pts.wt. of carbonyl modified olefin resin per 100pts.wt. of the composition A is melted and kneaded. Then said kneaded melt is fed into the die provided with an accumulating mechanism, and the parison amount corresponding to a vessel weight is accumulated. The accumulated melt is discharged into the form of a parison through a die slit in the condition where said discharged amount becomes 2-3,000g/sec, and the discharged parison is formed into the hollow shape of the vessel. Thus, the kneaded melt of resin composition is once accumulated, and then the amount to be discharged in above-mentioned range, is discharged from a die slit, and is formed into the shape of the parison, whereby a lamellar distribution structure is formed and excellent high barrier properties may be provided.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention has excellent gas barrier properties and a capacity of 3.512
This relates to a plastic container with a large capacity.

(Prior art and its problems) Conventionally, resin compositions made of polyolefin and ethylene-vinyl alcohol copolymer or linear polyamide have excellent processability and gas barrier properties, and containers have been made using such resin compositions. It is known that molding
-7038, Special Publication No. 51-41657).

However, even if the high gas barrier properties of the resin composition as described above are effectively exhibited in the case of small-capacity containers such as general food containers, the capacity is 3.5 i! When used in large containers such as those mentioned above, there is a problem in that sufficient gas barrier properties cannot be obtained.

That is, the container to which the above-mentioned prior art is directed has a small capacity, and the thickness of the container is extremely thin, about 0.5 mm at most.

On the other hand, in the case of the above-mentioned large-capacity containers, the thickness of the container wall is usually in the range of 0.7 mm or more, which is significantly thicker than that of small-capacity containers. The manufacturing conditions for these containers are significantly different from those for small-capacity containers, and it is thought that these differences in manufacturing conditions are responsible for the deterioration of gas barrier properties in large-capacity containers.

(Means for Solving the Problems) The present inventors have conducted intensive studies on a method for manufacturing large capacity containers using a resin composition comprising a polyolefin and an ethylene/vinyl alcohol copolymer or a linear polyamide. After melting and kneading the composition, an amount of parison corresponding to the basis weight of the container is stored, and then the melt is discharged in the shape of a parison through a die slit at a discharge amount within a certain range, and then into the shape of a container. Hollow molding (blow molding)
It has been found that a large-capacity container with excellent gas barrier properties can be obtained when this is carried out.

That is, according to the present invention, f1) (A) a composition containing a polyolefin and an ethylene-vinyl alcohol copolymer or a linear polyamide in a weight ratio of 99:1 to 75:25, or FB+the above composition 100 0.5 per part by weight
After melt-kneading a composition containing 20 parts by weight of carbonyl-modified olefin resin, supplying the composition to a die equipped with a storage mechanism to store an amount of parison corresponding to the basis weight of the container,
A high gas barrier characterized by discharging the stored melt in the shape of a parison through a die slit at a discharge rate of 2 to 3000 g/sec, and blow-molding the discharged parison into the shape of a container. A method for manufacturing a large capacity container is provided.

(Function) In the present invention, by temporarily storing the mixed melt of the resin composition in a storage mechanism provided in a tie,
It becomes possible to always maintain the discharge pressure from the die slit within a certain range.

That is, when manufacturing a large capacity container, if the discharge is performed directly from the die slit without going through such a storage mechanism, the discharge pressure tends to fluctuate, and the tip of the discharged parison is cooled, resulting in the problem described below. For this reason, blowing failures often occur, and even if blow molding into the shape of a container can be achieved, it is recognized that high gas barrier properties cannot be obtained in the container.

Further, a large extruder is required to continuously discharge the resin, but if a storage mechanism is provided, there is no need to use a particularly large extruder.

Further, in the present invention, the discharge rate of the melt from the die slit is set at 2 to 3000 g/sec, particularly 5 to 27 g/sec.
It is also important to keep it in the range of 0.00 g/sec. That is, when a container is molded using a resin composition consisting of a polyolefin and an ethylene-vinyl alcohol copolymer (sometimes referred to as EVOH) or a linear polyamide, a layer in which the polyolefin is preferentially distributed and an EVOH or linear polyamide are formed. A layer in which polyamide is preferentially distributed is formed, and when such a layered distribution structure is formed, an excellent high gas barrier
It is known that sex is expressed (Special Publication No. 51-30
No. 104).

However, according to the present invention, for example, the kneaded bay melt of the resin composition supplied from an extruder is first stored and then discharged through a die slit at a discharge rate within the above range to be formed into a parison shape. , it is recognized that a layered distribution structure as described above is formed.

For example, if the molten mixture is discharged from a die slit without going through a storage mechanism, the discharge pressure will fluctuate, so the layered distribution structure as described above will not be formed.

When the discharge amount from the die slit is larger than the above range, the flow of the molten mixture becomes turbulent and homogeneous mixing of the polyolefin and EVOH or linear polyamide occurs, resulting in a layered distribution. No structure is formed. Furthermore, if the discharge amount is smaller than the above range, not only will the discharge time become longer and the molding cycle will take a longer time, but also problems such as blowing defects may occur during hollow molding of the parison. Become.

(Thus, according to the manufacturing method of the present invention, even in large-capacity containers, a layered distribution structure is formed on the container wall, and high gas barrier properties can be obtained.

(Preferred Embodiments of the Invention) As the polyolefin used in the present invention, any polyolefin that has conventionally been widely used for molding films, containers, etc. can be used.

As such a polyolefin, it is possible to use an olefin polymer or copolymer represented by the formula 0 % where R is a hydrogen atom or an alkyl group having 4 or less carbon atoms.

It is important that these olefin polymers or copolymers be crystalline in order to have sufficient mechanical strength when formed into a molded structure.

Examples of such polyolefins include low, medium or high density polyethylene, tactical polypropylene, crystalline ethylene-propylene copolymers, polybutene-1, polypentene-1.

Of course, the polyolefin used in the present invention is not limited to a homopolymer of olefins or a copolymer of two or more olefins, and may contain small amounts of other copolymers as long as the properties of the polyolefin are not essentially impaired. A copolymer containing other ethylenically unsaturated monomers, such as vinyl chloride, vinyl acetate, acrylic acid or its esters, meccrylic acid or its esters, in a polymerization component, for example, up to 5 mol%. Good too.

The molecular weight of the polyolefin used may generally be within a film-formable molecular weight range, for example, an average molecular weight of 5.
000 to 400000 [Melt Index (AS
TM-12381MI=0.05-5.0g/10mm
1 is generally preferably used.

Particularly suitable polyolefins for the present invention, in order of importance, are (1) high-density polyethylene with a density of 0.940 g/cc or more, (2) tactical polypropylene, and (3) with a density of 0.930 to 0.5 g/cc. 939g/cc medium density polyethylene, (4) density 0.917 to 0.9
Low-density polyethylene of 29 g/cc or less and blends thereof.

In the present invention, when the above-mentioned low-density polyethylene is used, it is possible to noticeably develop a layered structure with mutually different resin compositions, and it is also possible to improve properties such as transparency, flexibility, and impact resistance. However, when high-density polyethylene or high-density polypropylene is used, mechanical properties such as stiffness tensile strength and tear strength can be improved.

In the present invention, the above-mentioned polyolefin (a)
and EVOH or linear polyamide (bl) a:b
=99:1 to 75:25 In particular, a container is molded from a resin composition containing a weight ratio of 99.5 to 80:20.

By adopting such a blending ratio, the polymer composition differs in the thickness direction, but the polymer composition is substantially constant in the surface direction of the container wall, and the layers are continuous in the surface direction. A container with a layered structure is obtained.

The ethylene-vinyl alcohol copolymer used is usually obtained by saponifying an ethylene-vinyl acetate copolymer having an ethylene content of 25 to 50 mol % to a degree of saponification of 96% or more.

If the ethylene content in this saponified copolymer exceeds 50 mol%, the saponified copolymer will lose its gas permeability (gas barrier property) against gases such as oxygen.
This makes it difficult for the container wall to have a layered distribution structure in which the polymer composition differs in the thickness direction, which is not suitable for the purpose of the present invention.

On the other hand, if the ethylene content of the saponified copolymer is lower than 25 mol %, it is not suitable for the purpose of the present invention because its hydrophilicity increases, water vapor permeability increases, and its melt moldability decreases.

Furthermore, the degree of saponification of the ethylene-vinyl acetate copolymer is 9
A content of 6% or more is necessary to improve the gas permeability of the container.

EVOH particularly preferably used in the present invention has an ethylene content of 25 to 45% and a saponification degree of 99.
% or more.

The molecular weight of EVOH used in the present invention is not particularly limited as long as it is within a molecular weight range that generally allows film formation.

The viscosity of EVOH is generally 85% by weight of phenol and 1% by weight of water.
The intrinsic viscosity [η
] is preferably in the range of 0.07 to Q, t7 ff/g. [If η is lower than 0.0712/g, the mechanical strength of the container will be unsatisfactory, while if [η] is higher than 0.1742/g, the moldability of the resin composition will be poor. There is a tendency to decrease.

Polyamides that can be used in place of the ethylene-vinyl alcohol copolymer include polyamides consisting of repeating units represented by the following formula, where n is a number from 3 to 13 and m is a number from 4 to 11. An example is as follows.

Poly-ω-aminocaproic acid, poly-ω-aminoheptanoic acid, poly-ω-aminocaprylic acid, poly-ω-aminocaproic acid, poly-ω-aminodecanoic acid, poly-ω-aminoundecanoic acid, poly-ω-amino Dodecanoic acid, poly-ω-aminotridecanoic acid, polyhexamethylene adipamide, polyhexamethylene dodecamide, polyhexamethylene dodecamide, polyhexamethylene tridecamide, polydecamethylene adipamide, polydeca Methylene adipamide, polydecamethylene dodecamide, polydecamethylene tridecamide, polydodecamethylene adipamide, polydecamethylene adipamide, polydodecamethylene dodecamide,
Polydodecamethylene tridecamide, polytridecamethylene adipamide, polytridecamethylene adipamide, polytridecamethylene dodecamide, polytridecamethylene tridecamide, polydecamethylene adipamide, polydecamethylene azeramide Homopolyamide 1 such as , polydobyl methylene azeramide, polytridobyl methylene azeramide, etc.
36 Caprolactam/laurin lactam copolymer, caprolactam/hexamethylene diammonium adipate copolymer, laurin lactam/hexamethylene diammonium adipate copolymer, hexamethylene diammonium adipate/hexamethylene diammonium sebacate copolymer, ethylene diammonium adipate copolymer Copolyamides such as ammonium adipate/hexamethylene diammonium adipate copolymer and caprolactam/hexamethylene diammonium azivert/hexamethylene diammonium sebacate copolymer can be mentioned.

These homopolyamides and copolyamides can also be used in the form of so-called blends, such as blends of polycaprolactam and polyhexamethylene adipamide, blends of polycaprolactam and caprolactam/hexamethylene diammonium adipate copolymer, etc. However, any of them can be used for the purposes of the present invention.

These polyamides are substantially linear and have a melt forming temperature of the final resin composition, e.g.
It must melt at a temperature of °C.

In the present invention, those that are easily available and particularly desirable for the purpose of the present invention are poly-ω-aminocaproic acid, poly-
These are aliphatic polyamides such as ω-aminoundecanoic acid, poly-ω-aminododecanoic acid, polyhexamethylene adipamide, polyhexamethylene dodecamide, and caprolactam/hexamethylene diammonium adipate copolymer.

The molecular weight of these polyamides may be sufficient to form a film on -H. This molecular weight range is 9
at a concentration of lOg polyamide in 8% sulfuric acid lI2 and at 20°C.
The relative viscosity measured at the temperature of
, particularly preferably t, can be expressed as a range from a to 4.0.

In the present invention, the above-mentioned resin composition used for molding the container includes the composition in order to improve the smoothness, uniformity, etc. of the surface of the container, and to improve processability or workability during molding. It is desirable to blend 0.5 to 20 parts by weight of carbonyl-modified olefin resin per 100 parts by weight.

Such a modified olefin resin has a carboxylic acid, carboxylic anhydride, carboxylate, carboxylic acid amide or carboxylic ester group bonded to a polymer chain,
It can be obtained by copolymerizing ethylenically unsaturated monomers containing these groups with olefins, or by modifying polyolefins by means such as graft polymerization or block copolymerization.

Suitable examples of the carboxylic acid derivative group-containing ethylenically unsaturated monomers mentioned above are as follows.

■Carboxylic acid or carboxylic acid anhydride Niacrylic acid, methacrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic anhydride, crotonic acid, tetrahydrophthalic anhydride.

■Carboxylic acid amide: Acrylamide, methacrylamide, maleimide.

■Carboxylic acid ester; Vinyl esters such as vinyl acetate and vinyl propionate. and ethyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 3-hydroxypropyl (meth)acrylate, N-ethylaminoethyl (
(Meth)acrylates such as meth)acrylate.

Suitable examples of carbonyl-modified olefin copolymers are as follows.

Ethylene-vinyl acetate copolymer, for example, ethylene or propylene and acrylic acid or methacrylic acid, if necessary, copolymerize these ester monomers, and add sodium,
Copolymers formed by ionic crosslinking with alkali metal ions such as potassium, alkaline earth metal ions such as magnesium, zinc ions, organic cations, etc., such as ionomers (
Mitsui DuPont Polychemical Co., Ltd. Himilan).

Backbone polymers such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-buty-1 copolymer, ethylene-vinyl acetate copolymer, etc., maleic acid, maleic anhydride, acrylic acid, methacrylic acid, (meth)acrylate A copolymer obtained by grafting , (meth)acrylamide, etc.

These carbonyl-modified olefin resins have carbonyl groups (>C=O) based on carboxylic acids or derivatives thereof,
It is preferable that the concentration is 10 to 400 mmol per 100 g of the resin.

The modified olefin resin should have a molecular weight sufficient to form a film, and preferably has a melting point in the range of 50 to 200°C, particularly 70 to 160°C.

The resin composition used in the present invention may contain well-known compounding agents, such as ultraviolet absorbers, depending on the purpose of the container, etc.
Stabilizers, lubricants, antioxidants, pigments, dyes, antistatic agents, and the like can be blended according to known formulations.

In addition, other polymers such as olefin copolymers and diolefin polymers may be blended in an amount of up to 10 parts by weight within a range that does not substantially affect properties such as gas barrier properties and impact resistance. .

In the present invention, a large-capacity container is molded using the above-mentioned resin composition, and FIG. 1 shows the overall structure of an extrusion molding apparatus for suitably carrying out this molding.

In this device, a cylinder 2 and a ring piston 3 that slides up and down along the inner peripheral surface of the cylinder 2 are provided in the lower half of an accumulator head 1.

A core 4 is provided at the center of the accumulation rake head 1, passing through the ring piston 3 and fixed to the cylinder 2.

Further, inside the cylinder 2, a resin reservoir (resin reservoir) 5 is formed, which is partitioned by the ring piston 3 and surrounded by the cylinder 2 and the core 4. This resin storage chamber 5 contains a molten resin composition continuously extruded from an extruder 6.

It is supplied through an annular communication path 7 connected to an extruder 6.

Further, the cylinder 2 is provided with a temperature adjustment mechanism (not shown) consisting of a heater, etc., and the temperature of the resin composition stored in the resin storage chamber 5 is adjusted to be within a certain range.

An annular die 8 is fixed concentrically to the lower end of the cylinder 2, an annular core support 9 is fixed to the lower end of the core 4, and the center of the core support 9 A core 10 concentric with the die 8 is fitted so as to be slidable in the vertical direction.

The inner peripheral surface of the lower end of the die 8 and the outer peripheral surface of the lower end of the core 10 are as follows:
Each of them is formed into a conical shape, and an annular die slit 11 is formed between them. This die slit 1
1 communicates with the resin storage chamber 5 through an annular resin passage 12 formed between the core 4 and the core support 9 .

In addition, the core 10 is connected to a hydraulic cylinder (
(not shown), so that the width of the die slit 11 formed between the die 8 and the die 8, that is, the thickness in the radial direction, is adjusted.

The ring piston 3 is lowered by a single-acting hydraulic cylinder 15 via a rod 14, and the hydraulic cylinder 15 and the ring piston 3 move the resin composition in the resin storage chamber 5 into the resin passage 12 and die. An accumulator 16 is configured to force feed into the slit 11.

According to the method of the present invention, the resin composition described above is melt-extruded using an extruder 6.

In this case, the premixing of the polyolefin, ethylene-vinyl alcohol copolymer, linear polyamide, carbonyl-modified olefin resin, etc. can be carried out by any method known per se, and is not particularly limited. For example, these polymers are in powder or granular form, and prior to melt extrusion,
Simply triblending (room temperature mixing) using a mixer or the like at room temperature is sufficient, and there is no particular need for mixing these in a molten state. It is also possible to use materials that have been melted and mixed, such as powder produced during molding.

Further, as the extruder 6 used, any well-known melt extruder can be used, but care must be taken so that the molten resin flow becomes a laminar flow, that is, mixing of each resin flow does not substantially occur. For this reason, it is desirable to use an extruder equipped with a full-flight screw such as a metering screw.

The resin composition melt-extruded from the extruder 6 is supplied to the resin storage chamber 5 through an annular communication path 7. In this case, the rod 13 is raised by the operation of the hydraulic cylinder, and the die slit 11 is thereby closed.

Therefore, as the melt of the resin composition is supplied to the resin storage chamber 5, the ring piston 3 rises, and thus a parison amount of the melt corresponding to the basis weight of the container is stored in the resin storage chamber 5.

Next, the rod 13 is lowered by the action of the hydraulic cylinder, and the die 10 is also lowered accordingly, and the die slit 11 is lowered.
A predetermined gap is maintained between the two.

In this state, the accumulator 16 is activated and the ring piston 3 is lowered to open the resin passage 12 and the die slit 1.
A melt of the resin composition is discharged through 1.

In the present invention, the discharge rate of the melt from the die slit 11 is 2 to 3000 g/s as already detailed.
ee, especially adjusted to be in the range of 5 to 2700 g/sec.

Further, in order to maintain the discharge amount within the above range, the discharge pressure from the die slit 11 by the single-acting hydraulic cylinder 15 is generally 5 to 8000 kg/cm2, particularly 10 to 5000 kg/cm2, although it varies depending on the size of the cylinder.
kg/c+n” range.

When this discharge pressure is less than 5 kg/cm2,
There is almost no difference between the average flow velocity of the polyolefin resin flow and the average flow velocity of the EVOH or linear polyamide flow, making it difficult to provide the desired layered distribution structure on the container wall. Moreover, since the discharge speed of the parison from the die slit 11 becomes low, the parison becomes cold, which is undesirable.

Furthermore, if the discharge pressure exceeds 8000 kg/cm'', mixing of the resin melt flow occurs, which tends to make it difficult to provide the desired layered distribution structure.

Further, in the present invention, the discharge temperature of the melt, that is, the temperature of the melt stored in the storage chamber 5, is set to be 2 to 50°C, particularly, higher than the melting point of the ethylene-vinyl alcohol copolymer or cotton-like polyamide. It is desirable to adjust the temperature to a temperature 3 to 40°C higher. If this temperature is lower than the above range, the molding temperature approaches the melting point of EVOH or linear polyamide, so the layered structure of the container wall tends to become discontinuous in the plane direction, and if it is higher than the above range. In this case, EVO
There is a tendency for deterioration due to oxidation or thermal decomposition of H or linear polyamide, and in either case it becomes difficult to obtain a sufficiently high gas barrier property.

According to the invention, the melt is discharged through the die slit 11 in the form of a parison, which is shaped into a container by blow-forming, which is known per se.

(Effects of the Invention) According to the present invention, it is possible to maintain sufficiently high gas barrier properties even in large-capacity containers at temperatures of 3.5° C. or higher.

Particularly in the case of large-capacity containers, unlike small-capacity containers such as those for grain products, it is extremely difficult to construct the container with a multilayered laminate, so it is difficult to obtain the high gas barrier properties described above. It should be understood that the present invention is extremely useful.

The invention is illustrated by the following example.

(Example) Support spindle The following four types of resins were tri-blended in a 50 g capacity tumbler type dry blender according to the following blending ratio.

■High-density polyethylene 45% density by weight (A
STM D-1505) 0.945g7cm"Saponification degree 99% Melting point 148℃ ■Low density polyethylene 45% by weight Density (A
STM D-150510, 922g/cm3M I
(ASTM D-123810, 50g/lomin melting point 108℃ ■ Ethylene-vinyl alcohol copolymer
5% by weight Ethylene content 30mo1% Degree of saponification 99% Intrinsic viscosity 0.15β/g Melting point 182℃ ■Ionomer 5% by weight (ethylene-methyl methacrylate copolymer with ionic bonds with sodium ions) Ethylene content 96m
o1% Density (ASTM D-150510, 945g/cm'
M I (ASTM D-1238) 1. O
g/lomin melting point 106°C Furthermore, in the apparatus shown in Fig. 1, extrusion molding is performed using an extruder 6 equipped with a full-flight screw (diameter: 60 mm, ratio of effective length to diameter: 22). using the device.

The tri-blend product was fed into the extruder 6 and melt-extruded, and the blended melt having a container basis weight was stored in the storage chamber 5 of the molding device and discharged from the die slit 11 to mold a parison.

The molding conditions at this time were as follows.

Indicated temperature (extruder X'llJ knee supply section) 170℃
Indicated temperature (storage chamber) 180℃ indicated temperature
(Tie slit part) 200
″C resin temperature (parison temperature)
202℃ discharge pressure 450 Kg/c
m2 discharge rate: 162 g/sec Using this parison, a large-capacity container having an average thickness of 3.93 mm, a dripping capacity of 2362 mm, and a weight of 1.63 kg was manufactured by a blow molding method known per se.

The center portion of the body of this container was cut out to about 1.5 m square, and the cut surface of the cut test piece was thoroughly polished with sandpaper, and then dyed with a 1 wt % Congo red aqueous solution at 85°C.

When the cut surface and partially peeled surface of this dyed test piece were observed using a stereomicroscope, it was found that the red-stained portion, that is, the ethylene-vinyl alcohol copolymer layer, was continuously distributed in a layered manner in the axial direction of the bottle. It was recognized that there was.

In addition, when the oxygen permeability of this container was measured by gas chromatography method (see Japanese Patent Publication No. 57-48459), it was found to be 0.33cc/bottle-day・atm [37
The temperature was 1°C.

For comparison, the high-density polyethylene from 1) above was discharged and blow-molded under the same conditions as above, and a large-capacity container with the same wall thickness, dripping volume, and weight as above was manufactured. When the oxygen permeability was measured in the same manner as above, 2
．． 43cc/bottle-day-atm [37℃1
Met.

Comparison■ For comparison, +1) discharge amount 1-5g/sec and (2)
Discharge blow molding was performed in exactly the same manner as in Example 1 except that the discharge rate was 3200 g/sec.

Under condition (1), the discharged parison cooled and could not be formed into a container.

Further, under the condition (2), it was possible to mold the product into a container.

According to the dyeing test for this container, the red dyed portions were distributed almost evenly throughout the container, indicating that the ethylene-vinyl alcohol copolymer was mixed almost homogeneously.

The oxygen permeability of this container is 2.36cc/bottle
-day・ata+ [37°C].

A triblend product was prepared in the same manner as in Example 1 except that the following 6-nylon was used instead of the ethylene-vinyl alcohol copolymer.

6-Nylon Melting point: 220°C Relative viscosity: 2.20 Using this triblend, a parison was molded under the following molding conditions, and a container was manufactured in the same manner as in Example 1.

Indicated temperature (extruder screw supply section) 210"C Indicated temperature (storage chamber) 225"C Indicated temperature (die slit section) 223"C Resin temperature
(Parison temperature) 225℃ Discharge pressure 4300 Kg7cm2 Discharge amount
The container obtained 715 g/sec.

Average thickness: 17, Omm.

Contents: 1042 Weight 7.25Kg Met.

When this container was subjected to the same dyeing test as in Example 1, it was found that 6-nylon was continuously distributed in a layered manner.

Also, the oxygen permeability of this container is 0.41cc/bottl
e・dayatm [It was 37℃1.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the overall configuration of an extrusion molding apparatus for suitably carrying out the method of the present invention. 1...Accumulator head 2...Cylinder 3...Ring piston 5...Resin storage chamber 6...Extruder 8...Die 9...Core support lO...Core 11...・Die slit Figure 1 Procedural Amendment (Koji) March 4, 1986 Kunio Ogawa, Commissioner of the Patent Office 1, Indication of the case Manufacturing method for high gas barrier large capacity containers 3, Person making the amendment Related Patent applicant 4, agent 〒105 5, no date of amendment order 7, contents of amendment fil page 8 line 14-15 of the specification [[melt index (ASTM-1238) MI=0.05-5 ．．
0 g/lOn+m] J is replaced by "[Melt Index (ASTM-1238) MI=
0.05-5.0 g/10mln]
Correct it to Jl. (2) “Ethylene-buty-1 copolymer” on all pages 17, lines 5-6 is corrected to “ethylene-butene-1 copolymer J.” (3) All pages 21, “Ethylene-buty-1 copolymer” In line 4, "Flash derived during molding" is corrected to "Flash J generated during molding." (4) In line 11 of page 23, "ethylene-vinyl alcohol copolymer" is corrected. is corrected as "Ethylene-vinyl alcohol copolymer J." (5) On page 25, line 4, "degree of saponification 99%" is corrected as Ir MI 0.33 g/lomin J. do. (6) At the bottom of page 28, line 66, the phrase ``instead of copolymer'' is corrected to ``j in place of copolymer.''

Claims (2)

[Claims] (1) (A) Polyolefin and ethylene/vinyl alcohol copolymer or linear polyamide in a ratio of 99:1 to 75
:25 weight ratio, or (B) a composition containing 0.5 to 20 parts by weight of carbonyl-modified olefin resin per 100 parts by weight of the composition, after melt-kneading the composition,
The melt is supplied to a die equipped with a storage mechanism to store an amount of parison corresponding to the basis weight of the container, and the stored melt is discharged in the shape of a parison through the die slit under conditions such that the discharge rate is 2 to 3000 g/sec. A method for manufacturing a large-capacity container with high gas barrier properties, which is characterized by blow molding the discharged parison into the shape of a container. (2) The manufacturing method according to claim 1, wherein the melt is discharged at a temperature of 2°C to 50°C higher than the melting point of the ethylene-vinyl alcohol copolymer or linear polyamide.