JP2003054591A - Squeezing multi-layered container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-layered container showing excellence in appearance, adhesion between layers, a squeezing property and a regrind property. SOLUTION: A squeezing multi-layered container comprises an intermediate layer of a resin composition (A) containing a saponified compound (A1) of an ethylene-vinylacetate copolymer and an olefin-vinylcarboxylate copolymer and/or its saponified compound (A2) and layers of a polyolefin-based resin (B) arranged on both sides of the intermediate layer wherein the whole layer of the resin composition (A) is located at a position distant by 55 to 98% of the thickness of the multi-layered container in the thickness direction from the inner side to the outside.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a squeezed multi-layer container using a resin composition of an ethylene-vinyl acetate copolymer saponified product (hereinafter abbreviated as EVOH), and more particularly to appearance properties, gas barrier properties, and interlayer properties. The present invention relates to a squeezed multilayer container excellent in adhesiveness, squeeze property and regrind property.

[0002]

EVOH is excellent in transparency, gas barrier property, aroma retaining property, solvent resistance, oil resistance and the like, and by utilizing such characteristics, food packaging materials, pharmaceutical packaging materials, industrial chemical packaging materials, pesticides, etc. It is used for various packaging materials such as packaging materials.

A typical example is a squeeze multi-layer container containing a viscous viscous food such as mayonnaise or ketchup, which is typically EVOH.
As a middle layer, and a polyolefin resin such as polyethylene is laminated on both outer layers. As a specific example, JP-A-60-125667 discloses low-density polyethylene as inner and outer layers and a middle layer. Is EVOH, and an adhesive resin layer containing acid-modified linear low-density polyethylene is arranged between the layers, and there is a disclosure of a multilayer plastic container.

However, in the construction of such a container, in addition to the two polyolefin resin layers inside and outside and the intermediate EVOH layer, two more adhesive resin layers are required, so that capital investment such as an extruder and a multilayer die is required. Is expensive, and the adhesive resin as a raw material is also expensive, which is economically disadvantageous in production. It goes without saying that it would be economically advantageous if the container can be constituted only by the polyolefin resin layer and the EVOH layer without the adhesive resin layer. However, since the polyolefin resin and EVOH have a poor chemical affinity, the interlayer adhesiveness between the two becomes insufficient unless an adhesive resin layer is provided, and delamination occurs during shipping and use of the container, resulting in commercial value. However, there is a problem that

As a countermeasure, it is considered that EVOH is blended with another resin to improve the interlayer adhesion, and conventionally, various blended products have been studied. For example, a method using a composition obtained by blending EVOH with an ionomer or an ethylene-vinyl acetate copolymer (JP-A-49-35482), a composition obtained by blending EVOH with nylon and a polyethylene copolymer containing a metal ion are used. Method used (Japanese Patent Laid-Open No. 49-10735)
No. 1), and a method using a composition obtained by blending EVOH with a polyolefin and a carbonyl group-containing thermoplastic polymer (JP-A-52-116387 and JP-A-54-4).
9285, JP-A-55-156579),
A method of using a composition in which an ethylene-α-olefin copolymer, a graft modified polymer, and a saponified ethylene-vinyl acetate copolymer having a high ethylene content are blended with EVOH (JP-A-54-53089), EVOH A method of using a composition obtained by blending a saponified product of an ethylene-vinyl acetate copolymer having a high ethylene content with polyvinyl alcohol (JP-A-54-156082), a composition obtained by blending two kinds of polyvinyl alcohol with EVOH. Has been proposed (JP-A-56-75856).

[0006]

However, when the present inventor examined the blended products described in each of the above publications in detail, JP-A-55-156579, JP-A-52-116387, In the blends disclosed in JP-A-54-49285 and JP-A-54-53089, the transparency and appearance of the squeezed multilayer container obtained may decrease depending on the thickness ratio of each layer.
Even the blend disclosed in JP-A-49-107351 is inferior in long-run melt moldability, and further the interlayer adhesion and squeeze property of the obtained squeezed multilayer container cannot be said to be sufficient. Even with the blends disclosed in Japanese Patent No. 156082 and Japanese Patent Laid-Open No. 56-75856, it may be difficult to obtain a squeezed multilayer container having good appearance because of its poor long-run melt moldability and regrindability. In JP-A-49-35482, when a blend of EVOH and an ethylene-vinyl acetate copolymer is used, the gas barrier property, the delamination strength, and the squeeze property are excellent although the appearance and the regrind property are excellent. It was found that the above are not always satisfactory, and the appearance, gas barrier property, interlayer adhesion, squeeze property, regrind property, etc. Excellent squeeze multilayer container in hand is the place to be desired.

[0007]

In view of such circumstances, the present inventor has studied in detail the EVOH blend used in a squeezed multilayer container and the position where the blend layer is placed. As a result, EVOH (A1 ) And an olefin-carboxylic acid vinyl ester copolymer and / or a saponified product (A2) thereof as a resin composition (A) layer as an intermediate layer, and a polyolefin resin (B) layer is arranged on both sides thereof. In the multi-layered container, all the resin composition (A) layers are 55 from the inner side to the outer side in the thickness direction of the multi-layered container.
It has been found that the squeezed multi-layer container arranged at the position of ˜98% meets the above-mentioned object and has completed the present invention.

That is, even if the EVOH blend as described in JP-A-49-35482 is used, all the blend layers are 55 to 98% from the inner side to the outer side in the thickness direction of the multilayer container. It is necessary to be arranged, and when even a part of the layer is out of this range, it becomes difficult to achieve the object of the present invention.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.

The EVOH (A1) used in the present invention is not particularly limited, but has an ethylene content of 10 to 70.
Mol% (further 20-60 mol%, especially 25-50
Mol%), a saponification degree of 90 mol% or more (further 95 mol% or more, particularly 99 mol% or more) is used.
When the ethylene content is less than 10 mol%, the gas barrier property and appearance of the squeezed-out multilayer container at high humidity are deteriorated.
When it exceeds mol%, sufficient gas barrier properties of the squeezed-out multi-layer container cannot be obtained, and when the saponification degree is less than 90 mol%, the gas barrier properties and moisture resistance of the squeezed-out multi-layered container are deteriorated, which is not preferable.

Further, the intrinsic viscosity of the EVOH (A1) (30% in a mixed solvent of 85% by weight of phenol and 15% by weight of water,
Measured at 0.6 ° C.) is 0.6 to 1.5 dl / g (further more than 0.
7-1.3 dl / g, especially 0.8-1.2 dl / g)
Is preferable, and the viscosity is less than 0.6 dl / g or 1.5.
Exceeding dl / g is not preferable because the extrusion moldability may become unstable.

Further, the melt flow rate (MFR) of the EVOH (A1) (measured at 210 ° C. and a load of 2160 g)
Is 0.5 to 100 g / 10 minutes (further 1 to 50 g /
10 minutes, particularly 3 to 35 g / 10 minutes) is preferable, and when the melt flow rate is smaller than the above range, the inside of the extruder is in a high torque state during molding, which makes extrusion process difficult, and more than the above range. If it is too large, the accuracy of the thickness of the resin composition (A) layer of the obtained squeezed multilayer container is reduced, which is not preferable.

The EVOH (A1) is obtained by saponification of an ethylene-vinyl acetate copolymer, and the ethylene-vinyl acetate copolymer is obtained by any known polymerization method such as solution polymerization, suspension polymerization, It may be produced by emulsion polymerization or the like, and saponification of an ethylene-vinyl acetate copolymer may be carried out by a known method.

Further, in the present invention, a copolymerizable monomer may be copolymerized within a range that does not impair the effects of the present invention. Examples of such a monomer include propylene, 1-butene,
Olefins such as isobutene, acrylic acid, methacrylic acid, crotonic acid, (anhydrous) phthalic acid, (anhydrous) maleic acid, (anhydrous) itaconic acid, and other unsaturated acids or salts thereof, or mono- or dialkyl having 1 to 18 carbon atoms Ester, acrylamide, C1-C18 N-alkyl acrylamide, N, N-dimethyl acrylamide, 2
-Acrylamidopropanesulfonic acid or salts thereof,
Acrylamide such as acrylamide propyl dimethyl amine or its acid salt or its quaternary salt, methacrylamide, N-alkyl methacrylamide having 1 to 18 carbon atoms, N, N-dimethyl methacrylamide, 2-methacrylamide propane sulfonic acid or the like Methacrylamides such as salts, methacrylamidopropyldimethylamine or its acid salts or quaternary salts thereof, N-vinylamides such as N-vinylpyrrolidone, N-vinylformamide and N-vinylacetamide, acrylonitrile,
Vinyl cyanides such as methacrylonitrile, carbon number 1 to
18 vinyl ethers such as alkyl vinyl ether, hydroxyalkyl vinyl ether, and alkoxy alkyl vinyl ether, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, vinyl halides such as vinyl bromide, vinylsilanes such as trimethoxyvinylsilane, acetic acid Allyl, allyl chloride, allyl alcohol, dimethylallyl alcohol, trimethyl- (3-acrylamido-3-dimethylpropyl) -ammonium chloride, acrylamido-2-methylpropanesulfonic acid and the like can be mentioned. Further, within the range that does not impair the gist of the present invention,
It may be post-modified such as urethanated, acetalized, cyanoethylated, etc.

It is also possible to use two or more different EVOHs as the EVOH (A1), in which case the ethylene content is 5 mol% or more (further 5 to 25 mol%, especially 8 to 20 mol%). Mol%) and / or the saponification degree is 1 mol% or more (further 1 to 15 mol%, especially 2).
EVOH which is different and / or has a MFR ratio of 2 or more (more preferably 3 to 20, especially 4 to 15).
The use of the blended product is useful because the flexibility, interlayer adhesion, squeezeability, blow moldability and the like are further improved while maintaining the gas barrier property. The method for producing two or more different EVOHs (blends) is not particularly limited. For example, a method of mixing each paste of EVA before saponification and then saponification, a mixture of alcohols of each EVOH after saponification or water and alcohol. Method of mixing solutions, each EVOH
And a method of melt-kneading after mixing.

Further, the olefin-carboxylic acid vinyl ester copolymer used in the resin composition (A) together with the EVOH (A1) and the saponified product (A2) thereof are carboxylic acid vinyl ester (containing olefin as a main component). General formula C
H ₂ ═CH—OCOR, where R is a linear or branched alkyl group having 0 to 20 carbon atoms) or a copolymerized carboxylic acid vinyl ester component (partially ) It is a saponified product that is saponified to form a hydroxyl group.

Examples of the olefin in the copolymer include ethylene, propylene, butylene, styrene and the like, among which ethylene is most preferably used. As the carboxylic acid vinyl ester in the copolymer, R in the above general formula is a linear or branched alkyl group having 0 to 20 carbon atoms, and examples thereof include vinyl formate, vinyl acetate and propionic acid. Examples thereof include vinyl, vinyl butyrate, vinyl octanoate, vinyl dodecanoate, vinyl stearate, and of these, vinyl acetate is most preferably used.

The carboxylic acid vinyl ester content of (A2) in the olefin-carboxylic acid vinyl ester copolymer is 1 to 60 mol% (more preferably 2 to 50 mol%, particularly 3 to 30 mol%). Is preferably used, and when the content of the carboxylic acid vinyl ester is less than 1 mol%, the interlayer adhesion, squeeze property and regrinding property of the obtained squeezed multilayer container may be insufficient. When it exceeds the above range, the thermal stability of the composition (A) tends to decrease, which is not preferable.

Melt flow rate (MF) of the copolymer
R) (measured at 190 ° C. and a load of 2160 g) is 0.1 to
100 g / 10 minutes (further 0.5 to 50 g / 10 minutes,
Particularly, 1 to 30 g / 10 min) is preferable because it has excellent compatibility with EVOH (A1) and the effects of the present invention can be more remarkably exhibited.

In the case of the saponified product (A2) of the olefin-carboxylic acid vinyl ester copolymer, the content of olefin in the saponified product (A2) is 40 to 99 mol%.
(Further, 50 to 98 mol%, particularly 70 to 97 mol%) is preferably used, and when the olefin content is less than 40 mol%, the thermal stability of the resin composition (A) tends to decrease. On the contrary, if it exceeds 99 mol%, the interlayer adhesion, squeeze property and regrind property of the obtained squeezed multilayer container may be insufficient, which is not preferable.

The saponification degree of the carboxylic acid vinyl ester component of the saponified product (A2) is not more than 99.9 mol% (more preferably 20 to 99.9 mol%, especially 40 to 99.9 mol%,
Particularly, 96-99.9 mol%) is preferably used, and when the saponification degree exceeds 99.9 mol%, the interlayer adhesion and squeeze property of the obtained squeezed multilayer container become insufficient. Is not preferred. Melt flow rate (MFR) of the saponified product (A2) (190 ° C, load 2160)
measured in g) is 0.5 to 100 g / 10 min (further 1
-50 g / 10 min, especially 2-30 g / 10 min)
It is preferable because it has excellent compatibility with VOH (A1) and the effects of the present invention can be more remarkably exhibited.

The olefin-carboxylic acid vinyl ester copolymer and the saponified product (A2) thereof may further include E
In order to improve the compatibility with VOH (A1), it may be a modified product containing a carboxyl group obtained by chemically bonding an unsaturated carboxylic acid or its anhydride by an addition reaction or a graft reaction. As the unsaturated carboxylic acid or its anhydride, for example, ethylenic unsaturated monocarboxylic acid such as acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, fumaric acid, itaconic acid, citraconic acid, maleic acid, maleic acid. Examples thereof include ethylenically unsaturated dicarboxylic acids such as monomethyl, monoethyl maleate and maleic anhydride, and anhydrides and half esters thereof. Among them, maleic anhydride is preferably used because of its excellent effect.

In the present invention, an olefin-carboxylic acid vinyl ester copolymer and its saponified product (A2) are further used.
In order to improve the compatibility between OH and EVOH (A1), a carboxyl obtained by chemically bonding an unsaturated carboxylic acid or its anhydride as a third component to an olefin polymer by an addition reaction or a graft reaction. It is also possible to blend a modified olefin polymer containing a group with EVOH (A1)
In the olefin-carboxylic acid vinyl ester copolymer and its saponified product (A2) in a good dispersed state, it is preferable in that the effects of the present invention can be more significantly exhibited. As such an unsaturated carboxylic acid or its anhydride Is maleic acid,
Examples thereof include maleic anhydride, fumaric acid, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, citraconic acid and hexahydrophthalic anhydride. Among them, maleic anhydride is preferably used because of its excellent effect. Specifically, maleic anhydride modified polyethylene, maleic anhydride modified polypropylene, maleic anhydride modified ethylene-propylene copolymer, maleic anhydride modified ethylene-methyl acrylate copolymer, maleic anhydride modified ethylene-
1 selected from ethyl acrylate copolymer, maleic anhydride modified ethylene-methyl methacrylate copolymer, maleic anhydride modified ethylene-ethyl methacrylate copolymer, maleic anhydride modified ethylene-vinyl acetate copolymer, etc.
One kind or a mixture of two or more kinds is preferable, and the amount of unsaturated carboxylic acid or its anhydride contained in the modified olefin polymer at this time is 0.001 to
3% by weight (further 0.01-1% by weight, especially 0.0
3 to 0.5% by weight) is preferable, and if the amount of modification in the modified product is small, the effect of improving the compatibility is poor, and conversely, if it is large, the thermal stability of the resin composition (A) may deteriorate, which is preferable. Absent.

In adding such a modified olefin polymer, EVOH (A1) and the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2) may be added at the same time during mixing such as melt kneading, or in advance. E
VOH (A1) or an olefin-carboxylic acid vinyl ester copolymer and / or a saponified product (A2) thereof may be mixed in advance by melt-kneading or the like. The content of the modified olefin polymer is not particularly limited, but is 1 to 100 parts by weight (more preferably 5 parts by weight with respect to 100 parts by weight of the olefin-carboxylic acid vinyl ester copolymer and / or the saponified product (A2) thereof. ˜80 parts by weight, particularly 20 to 50 parts by weight), and when the content is less than 1 part by weight, the effect of improving the compatibility is poor, and conversely 10
When the amount is more than 0 parts by weight, the thermal stability of the resin composition (A) may be deteriorated, which is not preferable.

In the present invention, as the olefin-carboxylic acid vinyl ester copolymer and / or the saponified product (A2), two or more kinds of olefin-carboxylic acid vinyl ester having different kinds, structures, compositions, molecular weights (MFR) and the like are used. A copolymer and / or a saponified product (A2) thereof may be blended and used.

The content ratio of (A1) and (A2) in the above resin composition (A) is not particularly limited, but the content weight ratio (A1 / A2) is 50/50 to 99/1 (further, 6).
0/40 to 97/3, especially 70/30 to 95/5) is preferable, and when the weight ratio is smaller than 50/50, the gas barrier property of the squeezed-out multilayer container may be insufficient. When it is larger than 99/1, the appearance, interlayer adhesion, squeeze property and regrind property of the squeezed-out multilayer container may be insufficient, which is not preferable.

In blending the above (A1) and (A2), there is no particular limitation, and known methods such as a method of melt-kneading the both and a method of mixing in a solution state can be adopted, For this, a method of melt kneading is advantageous.

The melt kneading is not particularly limited as long as (A1) and (A2) are sufficiently melt kneaded.
A known method can be adopted. For example, a known kneading device such as a kneader ruder, an extruder, a mixing roll, a Banbury mixer, a plastomill can be used, and usually 100 to 300 ° C (further 150 to 28).
It is preferable to perform melt-kneading at 0 ° C.) for about 1 minute to 1 hour, and it is industrially advantageous to use an extruder such as a single-screw extruder or a twin-screw extruder. It is also preferable to provide a suction device, a gear pump device, a screen device and the like. In particular, in order to remove water and by-products (pyrolysis low molecular weight substances, etc.), one or more vent holes are provided in the extruder to suck under reduced pressure, and to prevent oxygen from mixing into the extruder. By continuously supplying an inert gas such as nitrogen into the hopper, it is possible to obtain a resin composition (A) with excellent quality in which thermal coloring and thermal deterioration are reduced. In the melt-kneading, 1) solid (A1) and (A2)
A method of collectively mixing and melt-kneading, 2) a method of adding solid (A2) to a molten state (A1) and melt-kneading,
3) A method in which solid (A1) is added to melted (A2) and melt-kneaded, 4) A method in which melted (A1) and (A2) are mixed and melt-kneaded .

In the present invention, the water content is 1 to 60% by weight.
When EVOH (A1) is melt-kneaded with the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2), it is excellent in the mixing property of (A1) and (A2), and the heat coloring and heat It is particularly preferable because it is possible to obtain a resin composition (A) of excellent quality with reduced deterioration, and it is easy to handle that the EVOH (A1) pelletized water-containing material having excellent water absorption is used. Particularly preferred, the method will be described below, but the method is not limited thereto.

No particular limitation is imposed on obtaining EVOH (A1) pellets having a water content of 1 to 60% by weight.
During the step of producing VOH (A1), that is, in the step of extruding a solution of EVOH (A1) into a coagulating solution in a strand form to coagulate it, and then cutting it into pellets and then washing with water, EVOH ( A1) The water content of the pellet is 1 to
60% by weight (further 1 to 45% by weight, especially 1 to 30%
% By weight). If the water content is less than 1% by weight, the effects of the blending method (mixing property, suppression of heat deterioration and coloration, production efficiency, etc.) cannot be sufficiently exhibited, and if it exceeds 60% by weight, melting occurs. During the kneading, the resin and water are partially separated from each other, which makes the melt kneading unstable, which is not preferable.

The EVOH before melt-kneading referred to here
The water content of (A1) is measured and calculated by the following method.

[Measurement Method of Water Content] EVOH (A1) was weighed by an electronic balance (W1: unit g), put in a hot air oven type drier maintained at 150 ° C., and dried for 5 hours, and then further. The weight after allowing to cool in a desiccator for 30 minutes is similarly weighed (W2: unit g) and calculated from the following equation (1). Moisture content (%) = {(W1-W2) / W1} × 100 (1)

The method for obtaining such water-containing EVOH (A1) (pellets) will be described in detail below. EVOH (A1) used in the present invention is obtained by saponifying an ethylene-vinyl acetate copolymer as described above, and the saponification reaction is carried out in the presence of an alkali catalyst. As the catalyst, a conventionally known catalyst used for the saponification reaction of polyvinyl acetate and ethylene-vinyl acetate copolymer with an alkali catalyst can be used as it is. Specifically, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide and lithium hydroxide, sodium methylate, alkali metal alcoholates such as potassium t-butoxide, 1,8-diazabicyclo [5,4,10]. A cobasic amine represented by undecene-7 (DBU), an alkali metal carbonate, an alkali metal hydrogencarbonate and the like can be mentioned, but sodium hydroxide is preferably used from the viewpoint of easy handling, catalyst cost and the like.

The amount of the catalyst used varies depending on the required degree of saponification, reaction temperature and the like, but is used in an amount of 0.05 equivalents or less, preferably 0.03 equivalents, relative to the residual acetic acid groups in the ethylene-vinyl acetate copolymer. It is the following. It is also possible to use an acid catalyst such as hydrochloric acid or sulfuric acid instead of the alkali catalyst.

In the saponification, the above ethylene-vinyl acetate copolymer is dissolved in alcohol or an alcohol-containing medium to a concentration of about 20 to 60% by weight, and an alkali catalyst or an acid catalyst is added. 40-1
The reaction is carried out at a temperature of 40 ° C. If the EVOH (A1) after the reaction is not deposited at the solution temperature, the E
The concentration of VOH (A1) is not particularly limited, but it is usually 10 to 55% by weight, preferably 15 to 50% by weight.

Next, the alcohol solution of EVOH (A1) obtained above may be used as it is, but preferably, water is added directly, or the EVOH (A1) solution is appropriately concentrated or diluted and then water is added. To prepare a solution for strand production. In the case of the aqueous solution, the mixing weight ratio of water / alcohol is in the range of 80/20 to 5/95, and the content A (% by weight) of alcohol is 2.55E-40.75 ≦ A.
≤2.55E-15.75 (where E is EV
It is preferable that the ethylene content (mol%) of OH (A1) is satisfied from the viewpoint of the stability of the solution, and the amount of EVOH (A1) contained in the solution is 20 to 55% by weight ( Further, 25 to 50% by weight) is preferable from the viewpoint of stability of the subsequent coagulation work.

Next, the EVOH (A1) solution obtained above is extruded in a strand form and pelletized. At this point, saturated aliphatic amide (eg stearic acid amide), unsaturated fatty acid amide (eg Oleic acid amide, etc.), bis fatty acid amide (eg, ethylene bisstearic acid amide, etc.), higher fatty acid metal salt (eg, calcium stearate, etc.), low molecular weight polyolefin (eg, low molecular weight polyethylene having a molecular weight of about 500 to 10,000, or low molecular weight). Lubricant such as polypropylene)
Inorganic acids (eg phosphoric acid, boric acid etc.), organic acids (eg acetic acid, stearic acid etc.), inorganic salts (eg phosphoric acid alkali metal / alkaline earth metal salts, hydrotalcite etc.), organic acid salts (eg Alkali metal and alkaline earth metal salts of acetic acid), plasticizers (eg ethylene glycol,
Aliphatic polyhydric alcohols such as glycerin and hexanediol), antioxidants (eg IRGANOX 1098 manufactured by Ciba Specialty Chemicals), UV absorbers, colorants, antibacterial agents, antiblocking agents (eg talc particles), slip agents (For example, amorphous silica fine particles and the like), inorganic filler (for example, silicon oxide, titanium dioxide, clay, talc, bentonite, water-swelling phyllosilicate, etc.) may be blended.

As the coagulating liquid to be precipitated, water or a water / alcohol mixed solvent, aromatic hydrocarbons such as benzene, ketones such as acetone and methyl ethyl ketone, ethers such as dipropyl ether, methyl acetate, ethyl acetate and propionic acid. Organic acid esters such as methyl are used,
Water or a water / alcohol mixed solvent is preferable from the viewpoint of easy handling. As the alcohol, alcohols such as methanol, ethanol and propanol are used, but methanol is preferably used industrially.

The weight ratio of the coagulating liquid in the coagulating liquid and the strand of EVOH (A1) (coagulating liquid / strand of EVOH (A1)) is preferably 50 to 10,000, more preferably 100 to 1,000. . By setting the weight ratio within this range, it becomes possible to obtain EVOH (A1) pellets having a uniform size distribution.

Further, 1 to 1 of carboxylic acid is added to the coagulating liquid.
1 to 0000 ppm and / or carboxylic acid metal salt
It is also preferable to contain 15000 ppm and / or 1 to 50000 ppm of carboxylic acid ester, and further it is preferable to contain 50 to 5000 ppm of carboxylic acid and / or 10 to 5000 ppm of metal salt of carboxylic acid and / or 10 to 10,000 ppm of carboxylic acid ester. preferable. By containing carboxylic acids in the above range in the coagulation bath, EVOH (A
1) It becomes possible to obtain pellets more suitably.

The carboxylic acid is not particularly limited, but includes formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, crotonic acid,
Maleic acid, itaconic acid and the like can be mentioned, but acetic acid is preferably used. The metal salt of carboxylic acid is not particularly limited, and sodium formate, potassium formate, magnesium formate, calcium formate, sodium acetate, potassium acetate, magnesium acetate and the like are used, but sodium acetate is preferably used. The carboxylic acid ester is not particularly limited, but methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, methyl acetoacetate, ethyl acetoacetate and the like can be used. Preferably methyl acetate is used.

The temperature at which the EVOH (A1) solution is brought into contact with the coagulating liquid is preferably -10 to 40 ° C, more preferably 0 to 20.
C., in particular 0-10.degree. The EVOH (A1) solution is extruded in a strand shape into the coagulating liquid as described above by a nozzle having an arbitrary shape. The shape of such a nozzle is not particularly limited, but a cylindrical shape is preferable and The length is preferably 1 to 100 cm, more preferably 3 to 30 cm, and the inner diameter is preferably 0.1 to 10 cm,
Furthermore, it is 0.2 to 5.0 cm.

Thus, the EVOH (A1) (solution) is extruded from the nozzle in the form of a strand, but the number of strands is not necessarily one and can be extruded in any number between several and several hundreds. is there.

Finally EVO extruded in a strand shape
H (A1) is cut after it has sufficiently solidified, pelletized, and then washed with water. As for the shape of such pellets, those having a cylindrical shape having a diameter of 1 to 10 mm and a length of 1 to 10 mm (further, each having a diameter of 2 to 6 mm), and those having a spherical shape having a diameter of 1 to 10 mm (further Is preferably 2 to 6 mm).

As the washing conditions, the pellets are washed in a water bath at a temperature of 10 to 40 ° C (further 20 to 40 ° C). By such a water washing treatment, oligomers and impurities in EVOH (A1) are removed. Further, after the water washing treatment, or instead of the water washing treatment, the EVOH (A1) may be treated with an aqueous solution containing various acids or metal salts so that the EVOH (A1) contains the acid or metal salt. The EVOH (A1) and the composition (A) after blending are improved in color tone, thermal stability, long-run moldability, appearance of the resulting squeezed multilayer container, interlayer adhesion, heat stretch moldability, regrindability, etc. Preferred in terms of the acid component, such acid components include acetic acid, propionic acid, butyric acid, lauric acid, stearic acid, oleic acid, organic acids such as behenic acid and sulfuric acid, sulfurous acid, carbonic acid, boric acid, inorganic acids such as phosphoric acid. The metal salts include metal salts of the above-mentioned acids such as alkali metals, alkaline earth metals and transition metals, and acetic acid, phosphoric acid, boric acid and alkali metal salts thereof, and alkaline earth metal salts are particularly effective. Favored in terms Used well.

By the above method, EVOH (A
1) Pellets are obtained, but EV before melt-kneading
When adjusting the water content of the OH (A1) pellets, known drying treatment (hot air drying, dielectric heating drying, microwave irradiation drying, etc.) or removal of water adhering to the surface of the water-containing pellets may be performed in advance if necessary. In terms of stability of melt-kneading, it is preferable.

Subsequently, the EVOH (A1) having a water content of 1 to 60% by weight obtained above and the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2) are melt-kneaded to obtain a resin composition. A method for obtaining the product (A) will be specifically described.

EVOH (A1) having a water content of 1 to 60% by weight and an olefin-carboxylic acid vinyl ester copolymer and /
Or, in melting and kneading the saponified product (A2),
For example, a melt extruder, a kneader ruder, a mixing roll, a Banbury mixer, can be carried out using a known melt-kneading device such as a plastomill, usually it is industrially preferable to use a single-screw or twin-screw extruder, In particular, a twin-screw extruder is preferably used in view of stability of melt-kneading and homogeneity of blend, and a method using such a twin-screw extruder will be described in more detail.

The twin-screw extruder to be used is not particularly limited, but the inner diameter is 20 mm or more (further, 30 to 150 m).
m) is preferable, and if the inner diameter is less than 20 mm, productivity is poor, and L / D is 20.
-80 (further, 30-60) is preferable, and such L /
If the D diameter is less than 20, the ability to remove water may be insufficient, whereas if it exceeds 80, the residence time of the resin in the extruder becomes longer than necessary, which is unfavorable because of its thermal deterioration. Also, it is sufficient if there is at least one vent, especially 2
It is preferable that there are more than one place, and it is preferable that at least one of them is sucked under reduced pressure from the viewpoint of drying efficiency and quality of the obtained resin. For the shape of the die hole,
Although not limited, the diameter is 1 to 7 mm (further 2 to 5 mm) in consideration of obtaining a pellet having an appropriate shape and size.
(mm) circular shape is preferable, and the number of the holes is preferably about 3 to 100 (more preferably 10 to 50) in terms of production. Furthermore, it is also preferable to provide one or more mesh screens (especially two or more) between the extruder and the entrance of the die for removing foreign matters and stabilizing the resin pressure (stabilization of extrusion). In consideration of the above, it is also preferable to provide a gear pump, a heat exchanger, or the like.

The cylinder temperature of such an extruder is usually
It is preferable to select from the range of room temperature to 300 ° C (further, 50 to 280 ° C). Further, by the above temperature setting, the molten resin composition (A) is supplied to a die and extruded, but the temperature of the resin composition (A) in the die (resin temperature) is 150 to 300 ° C. It is also preferable to adjust the extrusion conditions (set temperature, screw shape, screw rotation speed, etc.) so as to be (more preferably 180 to 280 ° C.), and if the temperature is less than 150 ° C., extrusion may become unstable. Conversely, if the temperature exceeds 300 ° C., the quality of the composition (A) may deteriorate (heat deterioration), which is not preferable.

The rotation speed of the screw is 50 to 300 r.
If it is selected from the range of pm (further 80 to 200 rpm) and the number of rotations is less than 50 rpm, the ability to remove water may be insufficient, and conversely, if it exceeds 300 rpm, the quality of the resin composition (A) may be reduced. May decrease (heat deterioration), which is not preferable, and the discharge rate of the resin composition (A) is 10 to 400 kg / hr (further 20 to 3 kg).
00 kg / hr), and when the discharge rate is less than 10 kg / hr, it is unproductive and conversely 400 kg / hr.
If it exceeds kg / hr, sufficient water removal may not be possible, which is not preferable, and the residence time of the resin composition (A) in the extruder is selected from the range of 10 to 600 seconds (further 10 to 180 seconds). , If the residence time is less than 10 seconds,
In some cases, sufficient water removal may not be possible, and conversely, if it exceeds 600 seconds, the quality of the resin composition (A) may deteriorate (heat deterioration), which is not preferable, and the pressure applied to the resin composition (A) (resin Pressure) is selected from the range of 5 to 300 kg / cm ² (further 10 to 200 kg / cm ² ), and the applied pressure is less than 5 kg / cm ² and 300 kg / cm ^2.
Exceeding cm ² is not preferable because the extrusion may become unstable. It is also preferable to seal the inside of the hopper and around the vent hole with nitrogen in order to prevent thermal deterioration of the resin composition (A).

Thus, the resin composition (A) is obtained, and the water content of the finally obtained resin composition (A) is 1% by weight or less (further 0.001 to 0.5% by weight, In particular, 0.01 to 0.35% by weight) is preferable in that troubles such as foaming at the time of melt molding (extrusion blow molding etc.) of the squeezed multilayer container after melt kneading can be reduced.

In order to make the resin composition (A) have such a water content, for example, in the method using the above-mentioned twin-screw extruder, the resin temperature (extruder set temperature) is adjusted by adjusting various conditions. It is possible by adjusting the discharge amount (screw rotation speed and resin charging amount) and the like. The water content of the resin composition (A) after melt-kneading is measured and calculated by the following method.

[Measurement Method of Water Content] The resin composition (A) was weighed (W1 g) by an electronic balance, placed in a hot air oven type dryer maintained at 150 ° C., and dried for 5 hours.
Further, the weight after allowing to cool in a desiccator for 30 minutes is similarly weighed (W2g) and calculated from the following equation (2). Moisture content (%) = {(W1−W2) / W1} × 100 (2)

Further, after carrying out the melt-kneading described above, a known drying treatment (hot air drying, dielectric heating drying, microwave irradiation drying, etc.) is carried out as necessary, such as adjusting the water content of the resin composition (A). It is also possible to carry out together.

In the present invention, as described above, it is also possible to add an acid component or a metal salt thereof to the resin composition (A) so that the color tone, heat stability and long-run moldability of the resin composition (A) can be improved. The appearance of the obtained squeezed multilayer container, interlayer adhesion, heat stretch moldability, regrindability and the like are preferable, and such acid components include acetic acid, propionic acid, butyric acid, lauric acid, stearic acid, and oleic acid. ,
Organic acids such as behenic acid, sulfuric acid, sulfurous acid, carbonic acid, boric acid,
Examples of the inorganic acid such as phosphoric acid include metal salts such as alkali metal such as sodium salt, potassium salt, calcium salt, magnesium salt and zinc salt of the above acid, alkaline earth metal, transition metal and the like. In particular, acetic acid, phosphoric acid, boric acid, alkali metal salts thereof and alkaline earth metal salts thereof are preferably used because of their excellent effects.

The content of such acetic acid is 5 to 1000 ppm (more preferably 10 to 5) based on the resin composition (A).
00 ppm, particularly 20 to 300 ppm) is preferable, and if the content is less than 5 ppm, the content effect may not be sufficiently obtained, and conversely, if it exceeds 1000 ppm, the appearance of the squeezed multilayer container obtained is deteriorated. Or odor may be observed, which is not preferable.

The content of such phosphoric acid is 5 to 1000 ppm in terms of phosphoric acid radical based on the resin composition (A).
(Further 10-500ppm, especially 20-300p
pm), and the content is 5 ppm
If it is less than 100 ppm, the effect of the content may not be sufficiently obtained. On the contrary, if it exceeds 1000 ppm, the appearance of the squeezed multilayer container obtained may be deteriorated, which is not preferable.

The content of such boric acid is 10 to 10,000 ppm in terms of boron based on the resin composition (A).
(Further 20-5000 ppm, especially 50-200
0 ppm) is preferable, and the content is 10
If it is less than ppm, the effect of the content may not be sufficiently obtained, and conversely, if it exceeds 10,000 ppm, the appearance of the squeezed multilayer container may deteriorate, which is not preferable.

The content of the metal salt is 5 to 1000 ppm (further 10 to 500 ppm, especially 20 to 300 pp) in terms of metal based on the resin composition (A).
m) is preferable, and if the content is less than 5 ppm, the content effect may not be sufficiently obtained, and conversely, if it exceeds 1000 ppm, the appearance of the squeezed multilayer container obtained may be unfavorable. When the resin composition (A) contains two or more kinds of alkali metal and / or alkaline earth metal salts, the total amount thereof is preferably within the above range.

The method of incorporating the acid component and its metal salt in the resin composition (A) is not particularly limited, and it may be prepared in advance by E
VOH (A1) may be contained in the
It is contained in the carboxylic acid vinyl ester copolymer and / or its saponified product (A2), or at the same time when EVOH (A1) and the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2) are blended. It is possible to incorporate them, to incorporate them into the resin composition after blending the EVOH (A1) and the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2), or to combine these methods. In order to obtain the effect more markedly, it is preferable to preliminarily add EVOH (A1) to EVOH (A1) in terms of excellent dispersibility of the acid component and the metal salt thereof.

As a method of preliminarily containing it in EVOH (A1), the above-mentioned a) EVO having a water content of 20 to 80% by weight is used.
In addition to the method in which the porous precipitate of H (A1) is brought into contact with an aqueous solution of an acid component or its metal salt to contain the acid component or its metal salt and then dried, a) a uniform solution of EVOH (A1) (Method of adding acid component or its metal salt to (water / alcohol solution, etc.), extruding it into a coagulating liquid in a strand form, and then cutting the obtained strand to form pellets, and further drying treatment) A method in which EVOH (A1) and an acid component or its metal salt are mixed together and then melt-kneaded in an extruder, etc. d) The alkali (sodium hydroxide) used in the saponification step during the production of EVOH (A1) , Potassium hydroxide, etc.) with an acid component such as acetic acid, and the amount of residual acid components such as acetic acid and by-produced alkali metal salts such as sodium acetate and potassium acetate are adjusted by washing with water. And so on Kill. In order to obtain the effect more remarkably, a) which has excellent dispersibility of the acid component and its metal salt,
The method a) or d) is preferable, and the method a) or d) described above is particularly preferable in view of the industrial viewpoint.

Further, in the present invention, such a resin composition (A) may be used within the range not impairing the object of the present invention.
Saturated aliphatic amide (eg stearic acid amide etc.), unsaturated fatty acid amide (eg oleic acid amide etc.), bis fatty acid amide (eg ethylene bisstearic acid amide etc.), higher fatty acid metal salt (eg calcium stearate, magnesium stearate, Zinc stearate, etc., low molecular weight polyolefin (for example, molecular weight 500-
Lubricants such as low molecular weight polyethylene of about 10,000 or low molecular weight polypropylene, etc., inorganic salts (eg hydrotalcite etc.), plasticizers (eg aliphatic polyhydric alcohols such as ethylene glycol, glycerin, hexanediol etc.), Oxygen absorber [For example, as an inorganic oxygen absorber, reduced iron powder, further water-absorbing substances and electrolytes, aluminum powder, potassium sulfite, titanium oxide photocatalyst, etc. , Ascorbic acid, its fatty acid esters and metal salts,
Hydroquinone, gallic acid, polyhydric phenols such as hydroxyl group-containing phenol aldehyde resin, bis-salicylaldehyde-imine cobalt, tetraethylene pentamine cobalt, cobalt-Schiff base complex, porphyrins,
Macrocyclic polyamine complexes, coordination complexes of nitrogen-containing compounds such as polyethyleneimine-cobalt complexes with transition metals, terpene compounds, reactants of amino acids and hydroxyl group-containing reducing substances, triphenylmethyl compounds, etc. As a system oxygen absorber, a coordination bond between a nitrogen-containing resin and a transition metal (eg, a combination of MXD nylon and cobalt), a blend of a tertiary hydrogen-containing resin and a transition metal (eg, a combination of polypropylene and cobalt) , A blend of a carbon-carbon unsaturated bond-containing resin and a transition metal (eg, a combination of polybutadiene and cobalt), a photooxidatively degradable resin (eg: polyketone), an anthraquinone polymer (eg: polyvinyl anthraquinone), and the like, Photoinitiators (such as benzophenone), peroxide scavengers (such as commercially available antioxidants) and deodorants (active agents) Such as those obtained by adding coal or the like), heat stabilizers, light stabilizers, such as antioxidants (e.g., Ciba Specialty Chemicals "IRGANOX1098"),
UV absorbers, colorants, adhesives, antistatic agents, surfactants, antibacterial agents, antiblocking agents (such as talc particles), slip agents (such as amorphous silica), inorganic fillers (such as silicon oxide, dioxide) Titanium, clay, talc, bentonite, water-swelling phyllosilicate, etc.), other resin (for example, polyolefin resin, polyamide resin, polyester resin, etc.) may be blended.

The polyolefin resin (B) laminated with the above resin composition (A) includes linear low density polyethylene (LLDPE) and low density polyethylene (LDP).
E), ultra low density polyethylene (VLDPE), medium density polyethylene (MDPE), high density polyethylene (HDP)
E), ethylene-vinyl acetate copolymer (EVA), ionomer, ethylene-propylene (block or random) copolymer, ethylene-acrylic acid copolymer (EA)
A), ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer (EMAA), ethylene-methacrylic acid ester copolymer, polypropylene (P
P), propylene-α-olefin (α-olefin having 4 to 20 carbon atoms) copolymer, olefin homopolymer or copolymer such as polybutene, polypentene, polymethylpentene, or homopolymer or copolymer of these olefins. Examples include polyolefin resins in a broad sense such as those obtained by graft-modifying with an unsaturated carboxylic acid or its ester. In the appearance properties (transparency, surface gloss, etc.), interlayer adhesion, and squeezeability of the obtained squeezed multilayer container. In terms of excellentness, linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), ethylene-propylene (block or random) copolymer, polypropylene (PP), propylene-α-olefin (having 4 to 20 carbon atoms). (alpha-olefin) copolymer is preferable, especially melt flow rate (MFR) (190 degreeC, Measured in heavy 2160g) is 0.
1-2 g / 10 min (further 0.2-1.5 g / 10
Min, especially 0.3-1 g / 10 min) with a density of 0.92
0 to 0.930 g / cm ³ (further 0.920 to 0.
925 g / cm ³ ) low density polyethylene (LDPE)
Is most preferably used.

Further, in the present invention, it is also possible to use a blend of two or more kinds of polyolefin resins (B) having different kinds of resins and physical properties (density, MFR, molecular weight distribution, etc.). Further, the above-mentioned various additives, fillers, modifiers, other resins and the like may be added to the polyolefin resin (B) within a range that does not impair the object of the present invention.

The squeezed multilayer container of the present invention comprises the above resin composition (A) layer as an intermediate layer and the polyolefin resin (B) layer on both sides thereof. Will be described.

In producing the squeezed multilayer container of the present invention, the resin composition (A) is used as an intermediate layer, and the polyolefin resin (B) is laminated on both sides of the resin composition (A) to form a multilayer parison (preliminary hollow tubular pre-blown container). After making a molded product), place the parison in the mold and blow it into the mold by blowing fluid pressure such as air and water, and mold it into a hollow container such as a bottle or tube (blow molding). ).

The blow molding method is also not particularly limited, and the extrusion direct blow molding method (double head type, mold moving type, parison shift type, rotary type, accumulator type, horizontal parison type, etc.), cold parison type blow is used. Molding method, injection blow molding method, biaxial stretch blow molding method (extrusion cold parison biaxial stretch blow molding, injection cold parison biaxial stretch blow molding, injection molding in-line biaxial stretch blow molding, etc.) and the like, The extrusion direct blow molding method is most preferable from the viewpoint that the effects of the present invention can be exhibited most. Further, it is also preferable to further heat-treat the hollow container obtained by blow molding, because improvement in delamination resistance and gas barrier property can be recognized. Heat treatment temperature is 10
The heat treatment time is 0 to 240 ° C. and is 1 second or more.

Further, for the tubular squeezed multilayer container, a laminated sheet having the above-mentioned constitution is produced by coextrusion molding or the like, and the laminated sheets are superposed and joined to form a tubular shape, and one end of the tubular body portion is formed. By attaching a screw-shaped extrusion port formed by injection molding of a thermoplastic resin and a conical shoulder continuous with this to the part, and by closing the other end of the tubular body by fusion or the like. It is also possible to produce.

Thus, a squeezed multilayer container can be obtained. In the present invention, however, in the thickness direction of the multilayer container, all the resin composition (A) layers are 55 to 98% (more preferably 60%) from the inside to the outside. ~ 95%, especially 6
0 to 90%) is important, and when the resin composition (A) layer is outside this range or when the layer is partially outside this range, the squeezed multilayer obtained is The interlayer adhesion and squeeze property of the container are insufficient, and the object of the present invention cannot be achieved. When the resin composition (A) layer is composed of two or more layers, it is necessary that all the resin composition (A) layers are within the above range.

The layer structure of such a squeezed multilayer container is b / a / b, where a is a layer made of the resin composition (A) and b is a layer made of a polyolefin resin (B).
Not only the layer structure of b / a / b / a, b / a / b / a
/ B, b / a / b / a / b / a, b / a / b / a / b /
Any combination such as a / b is possible, and further,
When R is a regrind layer composed of a mixture of at least the resin composition (A) and the polyolefin resin (B), b / R / a / b, R / b / a / b, b / R / a / R
/ B, b / a / R / a / b, b / R / a / R / a / R /
b, b / R / a / b / a / R / b, etc. are also possible.

Particularly in blow molding, when producing such a multi-layer container, a large amount of scraps, unnecessary portions at the ends, and even defective products are usually produced, which is industrially involved. In terms of economy, it is necessary to recycle the composition (scrap composition) consisting of scraps generated at the time of molding, and it is preferable to use again as one of one or more layers of the multilayer container by melt molding as a regrind layer. The most preferable layer structure of the squeezed-out multilayer container is b / R / a / b, b / R / a / R / b, b
/ A / R / a / b and the like.

Generally, polyolefin resin (B) and E
When VOH and recycle are used as the regrind layer, the phase separation foreign matter (eye resin), which is considered to be due to the difference in melt viscosity between them and the incompatibility, is mixed into the regrind layer,
Although there may be some inconveniences such as delamination between the regrind layer and the adjacent layer and deterioration of mechanical properties such as impact resistance of the regrind layer, the resin composition (A) of the present invention may be used. When used, the problems of the regrind layer are reduced, and a squeezed multilayer container with good quality can be obtained, which is preferable.

In the squeezed-out multi-layer container of the present invention, an adhesive resin is not necessary between the layers, probably because the resin composition (A) has excellent affinity and adhesiveness with the polyolefin resin (B). To the extent that the object of the invention is not impaired,
It is also possible to provide an adhesive resin layer composed of a modified olefin-based polymer containing a carboxyl group chemically bonded to an unsaturated carboxylic acid or an anhydride thereof by an addition reaction or a graft reaction, and further, if necessary. Accordingly, a resin layer other than the resin composition (A) and the polyolefin resin (B) can be provided.

The thickness of each layer of the squeezed-out multilayer container of the present invention thus obtained cannot be generally determined depending on the layer structure, container form, container application, required physical properties, etc.
The layer is selected from the range of 1 to 200 μm (further 3 to 50 μm) and the layer b is selected from the range of 10 to 1000 μm (further 30 to 500 μm). If the layer a is less than 1 μm, the gas barrier property is insufficient, and its thickness control becomes unstable. On the contrary, if it exceeds 200 μm, the squeeze property is poor and it is not economically preferable, and if the layer b is less than 10 μm, the rigidity is insufficient. On the contrary, if it exceeds 1000 μm, the weight becomes large, the squeeze property is deteriorated, and it is not economical and not preferable.

Further, the thickness of all the layers of the squeezed-out multilayer container of the present invention cannot be unequivocally determined depending on the layer constitution, the container form, the use of the container, the required physical properties, etc., but it is usually 50 to 2000.
It is selected from the range of about μm (further, 150 to 600 μm). If the total layer thickness is less than 50 μm, the rigidity is insufficient,
On the other hand, if it exceeds 2000 μm, the weight becomes large, the squeeze property is deteriorated, and it is not economical and not preferable.

The ratio of the thickness of the resin composition (A) layer to the thickness of all layers of the squeezed multilayer container of the present invention is not particularly limited, but the thickness of the resin composition (A) layer is 1 to 20 of the total layer thickness. % (Further 1.5 to 15%, especially 2-1)
0%) is preferable, and if the thickness ratio is less than 1%, the gas barrier property of the squeezed-out multilayer container obtained may be poor, and conversely, if it exceeds 20%, the interlayer adhesion and squeeze property of the squeezed-out multilayer container obtained. However, the regrindability may be insufficient, which is not preferable.

The squeezed multilayer container composed of the bottles, tubes and the like obtained as described above is used in addition to general foods, seasonings,
Fermented foods, oil and fat foods, beverages, cosmetics, pharmaceuticals, detergents, cosmetics, industrial chemicals, pesticides, fuels, and various containers are useful. Specifically, mayonnaise, ketchup, sauce,
Viscous liquid or pasty foods such as miso, lard, jam, chocolate, butter, margarine, jelly, yogurt, wasabi, mustard, ginger, garlic, toothpaste, shampoo, rinse, conditioner, hair dye, and seasoning It is useful for foods, spices, beverages, cosmetics, pharmaceuticals, etc., and is particularly useful as a squeezed multilayer container (squeeze bottle) whose content is at least one selected from mayonnaise, ketchup and sauce.

[0079]

EXAMPLES The present invention will be specifically described below with reference to examples.

In the examples, "parts" and "%" are based on weight unless otherwise specified. For the measurement of the acetic acid content in EVOH (A1) and resin composition (A), see EV
OH (A1) and the resin composition (A) were extracted with hot water at 95 ° C. for 3 hours, and the acetic acid in the extract was neutralized and titrated with an aqueous sodium hydroxide solution. Further, regarding the measurement of the boric acid content in the EVOH (A1) and the resin composition (A), the EVOH (A1) and the resin composition (A) are alkali-melted and the boron is quantified by the ICP emission spectrometry. I went by.

Further, regarding the measurement of the alkali (earth) metal content, EVOH (A1) and the resin composition (A) were ashed, dissolved in hydrochloric acid aqueous solution, and then alkali (earth) was analyzed by atomic absorption spectrometry. This was done by quantifying the metal. The saponification degree of the carboxylic acid vinyl ester component of the saponified product (A2) of the olefin-carboxylic acid vinyl ester copolymer was determined by measuring the content of the carboxylic acid vinyl ester component according to JIS-K7192. .

Example 1 [Preparation of resin composition (A)] Ethylene content 32 mol%
To 1000 parts of a methanol solution containing 40% of the ethylene-vinyl acetate copolymer, 40 parts of a methanol solution containing 6% of sodium hydroxide and 2500 parts of methanol are continuously supplied, and methyl acetate and extra methanol by-produced. While distilling from the system, the saponification reaction is carried out at 110 ° C. for 2.5 hours, and the saponification degree of the vinyl acetate component is 99.5.
Obtained mol% EVOH. Next, in the saponification reaction completion liquid,
Excess methanol was distilled off while supplying 450 parts of 50% water-containing methanol at an azeotropic point to obtain a water / methanol mixed solution of EVOH [water / methanol = 50/50 (weight ratio), resin concentration 40%]. .

Subsequently, the EVOH solution (solution temperature 50 ° C.) was maintained at 5 ° C. with a coagulating liquid (water 9
5%, methanol 5%) is extruded into a strand into a tank to solidify EVOH into a strand, and then the strand EVOH is led to a take-up roller attached to the end of the water tank and cut with a cutter. , Diameter 4 mm,
White porous pellets with a length of 4 mm were obtained.

Further, the obtained white porous pellet was washed with a 0.5% acetic acid aqueous solution, and then washed with 0.1% acetic acid.
Pour into an aqueous solution containing 0.03% magnesium acetate and 0.02% calcium acetate and stir at 30 ° C. for 5 hours to prepare water-containing EVOH (A1) pellets [after drying EVOH
(A1) in acetic acid 100ppm, magnesium acetate 35p
pm (calculated as magnesium), calcium acetate 20ppm
(Containing calcium)] was obtained. Such hydrous EVO
The H (A1) pellets (water content 60%) were brought into contact with nitrogen gas in an atmosphere of 80 ° C. for 40 minutes by a tower fluidized bed dryer to obtain a water content of 25% and MFR 3.5 g / 10 minutes ( EVOH (A1) of 210 ℃, measured at a load of 2160g)
Pellets were obtained.

Then, 80 parts of the obtained hydrous EVOH (A1) pellets and a saponified product of ethylene-vinyl acetate copolymer [ethylene content 89 mol%, saponification degree of vinyl acetate component 95.5 mol%, MFR 4. 5g / 10 minutes (190
℃, measured at a load of 2160g), sodium acetate 150p
pm (sodium equivalent)] (A2) 20 parts after dry blending, it is supplied to a twin-screw extruder equipped with a strand die, melt-kneaded under the following conditions, and the strand is passed through a water tank. After cooling, cut with a pelletizer to obtain water content of 0.15%, acetic acid content of 80 ppm, sodium acetate content of 30 ppm (sodium conversion), magnesium acetate content of 28 ppm (magnesium conversion), calcium acetate content of 16 ppm. (Calcium equivalent) resin composition (A) pellets were obtained.

The resin composition (A) pellets thus obtained were visually observed and were colorless and no yellowing was observed at all. Further, such a composition could be efficiently obtained at a rate of 50 kg / hr. Further, the pelletizing is continuously performed for 10 times.
After a long period of time, strand breakage, foreign matter, eye blemishes, etc. were not observed at all, and pellets were obtained stably.

[Conditions for Melt Pelletization by Twin-screw Extruder] Screw outer diameter 30 mmΦ L / D 42 Strand die shape 2-hole screen mesh with diameter 3.5 mmΦ 90/90 mesh vent C4 is opened, C6 is nitrogen seal in a vacuum suction hopper The screw rotation speed is 120 rpm

The resin composition (A) obtained above and low-density polyethylene [Novatech LD manufactured by Nippon Polychem Co., Ltd.
ZE41 ", MFR 0.5 g / 10 min (measured at 190 ° C., load 2160 g), density 0.922 g / cm ³ ].
Using (B), these are supplied to a co-extrusion multilayer direct blow molding machine (manufactured by Placo Co.) to form a low density polyethylene (B) layer / resin composition (A) layer / low density polyethylene (B) layer constitution. After pushing out the multi-layer parison of No. 3, sandwich it with a mold and blow air to inflate it and make it adhere to the mold,
A squeezed multilayer container (capacity 500 cc, height 200 mm, barrel) having a structure of outer low-density polyethylene (B) layer (50 μm) / resin composition (A) layer (20 μm) / inner low-density polyethylene (B) layer (200 μm) Outside diameter 80m
A gourd-shaped multi-layer hollow bottle (m-50 mm) was obtained. Burrs and scraps generated at the time of molding such a squeezed multilayer container are crushed and subjected to an extruder for a regrind layer to similarly form an outer low-density polyethylene (B) layer (50 μm) / resin composition (A) layer ( 20 μm) / regrind layer (150
μm) / Inner low-density polyethylene (B) layer (50 μm)
Squeezed multi-layer container having the structure of (the shape is the same as above)
Got The resin composition (A) layer was at a position of about 74 to 81% from the inner side to the outer side in the thickness direction, and the thickness of the resin composition (A) layer was 7.4% of the total layer thickness.

The conditions from the parison molding to the blow molding were as follows. [Conditions of Single-Screw Extruder of Resin Composition (A)] Screw Inner Diameter 32 mm L / D 28 Extrusion Temperature C1: 180 ° C. H: 220 ° C. C: 200 ° C. N: 220 ° C. C: 220 ° C. D: 200 ° C. C4: 220 ° C

[0090] [Conditions of low density polyethylene (B) single screw extruder]     Screw inner diameter 40 mm     L / D 28     Extrusion temperature C1: 180 ° C H: 200 ° C                         C2: 200 ° C N: 200 ° C                         C3: 200 ° C D: 200 ° C                         C4: 200 ° C

[0091] [Conditions for regrind single screw extruder]     Screw inner diameter 40 mm     L / D 28     Extrusion temperature C1: 180 ° C H: 200 ° C                         C2: 200 ° C N: 200 ° C                         C3: 200 ° C D: 200 ° C                         C4: 200 ° C

The squeezed multilayer container (bottle) thus obtained was evaluated for appearance, gas barrier property, interlayer adhesion, squeeze property and regrind property as follows.

(Appearance) The body of the bottle obtained above was visually observed and evaluated according to the following criteria. ○: Vertical streaks and fish eyes are hardly observed, and transparency is good. △: Vertical streaks and fish eyes are slightly recognized, and transparency is slightly poor. Many are recognized and the transparency is poor.

(Gas Barrier Property) Oxygen permeability was measured by sealing the mouth surface of the bottle obtained above with an aluminum metal plate (temperature 23 ° C., outside 50% RH using “OXTRAN10 / 50” manufactured by Modern Control Co., Ltd.). , Inside 100% RH).

(Interlayer adhesion) A strip shape (width 15 mm, length 1 from the body of the bottle obtained above in the machine direction (MD))
(50 mm) test piece is cut out, the layer interface between the low-density polyethylene (B) layer and the resin composition (A) layer is peeled off, and both ends are grasped with a chuck of Autograph (manufactured by Shimadzu Corporation) and peeled by 180 °. (T peel) test was performed to measure the interlaminar peel strength (g / 15 mm). Peeling speed is 300
The measurement was performed in an atmosphere of mm / min, a temperature of 23 ° C., and a relative humidity of 50% RH.

(Squeeze property) The bottle obtained above was filled with 500 g of mayonnaise on the market, and 20 panelists were allowed to use the mayonnaise under the circumstance of actually using it. Easiness of deformation and appropriate restorability) were evaluated and evaluated according to the following criteria. ◎ ・ ・ ・ The number of people who answered that it was easy to extrude was 18 or more ○ ・ ・ ・ The number of people who answered that it was easy to extrude was 15 to 17 △ ・ ・ ・ The number of people who answered that it was easy to extrude was 10 to 14 × ・ ・ ・ Easy to extrude 9 people or less

(Regrinding property) In the bottle obtained above, the presence or absence of contamination of light yellow eye tars (phase-separated foreign matter) in the regrinding layer / adjacent layer and in the regrinding layer was visually observed. The following criteria were evaluated. ○: No eye blemishes were found. △: Eye blemishes were found slightly. X: Eye blemishes were found to some extent.

Example 2 In Example 1, the layer constitution of the bottle was as follows: outer low density polyethylene (B) layer (100 μm) / resin composition (A) layer (15 μm) / regrind layer (100 μm) / inner low density A multilayer container (bottle) was similarly squeezed out except that the polyethylene (B) layer (80 μm) was used, and the same evaluation was performed. The resin composition (A) layer was at a position of about 61 to 66% from the inner side to the outer side in the thickness direction, and the thickness of the resin composition (A) layer was 5.1% of the total layer thickness.

Example 3 The layer structure of the bottle in Example 1 was as follows: outer low density polyethylene (B) layer (40 μm) / resin composition (A) layer (8 μm) / regrind layer (60 μm) / resin composition A multilayer container (bottle) was squeezed out in the same manner except that the layer (A) (8 μm) / inner low-density polyethylene (B) layer (175 μm) was prepared and evaluated in the same manner. The resin composition (A) layer is about 60 to 63% (inner layer) and about 84 to 86% from the inner side to the outer side in the thickness direction.
The total thickness of the resin composition (A) layer was 5.5% of the total layer thickness at the (outer layer) position.

Example 4 In Example 1, as the component (A2), a saponified product of ethylene-vinyl acetate copolymer [ethylene content 89 mol%, saponification degree of vinyl acetate component 99.1 mol%, MFR
6.8 g / 10 minutes (measured at 190 ° C. and a load of 2160 g), sodium acetate 600 ppm (converted to sodium)
In the same manner as above except that the acetic acid content in the resin composition (A) [resin composition (A) is 80 ppm, sodium acetate content is 120 ppm (as sodium conversion), and magnesium acetate content is 28 ppm (magnesium). Conversion),
A calcium acetate content of 16 ppm (calculated as calcium) was obtained, and a multilayer container (bottle) was similarly squeezed out and evaluated in the same manner.

Example 5 In Example 4, the water content was 15% and the ethylene content was 29%.
Mol%, saponification degree 99.6 mol%, MFR after drying 4g
/ 10 minutes (210 ℃, load 2160g) EVOH (A
1) [Boric acid 150ppm in EVOH (A1) after drying
(Boron conversion), sodium acetate 100 ppm (conversion as sodium) was used in the same manner except that the resin composition (A) [the boric acid content in the resin composition (A) was 120 p.
pm (boron equivalent), sodium acetate content is 200p
pm (in terms of sodium)], a multilayer container (bottle) was similarly squeezed out and evaluated in the same manner. However, with respect to boric acid and sodium acetate in EVOH (A1), as in Example 1, the water / methanol solution of EVOH after the saponification step during EVOH production was extruded into a water tank in a strand shape to coagulate it and then with a cutter. After washing the pellet-shaped porous precipitate obtained by cutting with an aqueous acetic acid solution,
It was contained by adding it to an aqueous solution containing boric acid and sodium acetate and stirring.

Example 6 In Example 4, the layer constitution of the bottle was as follows: outer low density polyethylene (B) layer (80 μm) / resin composition (A) layer (15 μm) / regrind layer (100 μm) / inner low density A multilayer container (bottle) was similarly squeezed out except that the polyethylene (B) layer (100 μm) was used, and the same evaluation was performed. The resin composition (A) layer is at a position of about 68 to 73% from the inside to the outside in the thickness direction,
The thickness of the resin composition (A) layer was 5.1% of the total layer thickness.

Example 7 In Example 4, the outer layer of the low-density polyethylene (B) layer (30 μm) / resin composition (A) layer (8 μm) / regrind layer (50 μm) / resin composition was used as the layer structure of the bottle. A squeezed multilayer container (bottle) was prepared in the same manner except that the layer (A) (8 μm) / inner low-density polyethylene (B) layer (150 μm) was used, and the same evaluation was performed. The resin composition (A) layer is about 61 to 64% (inner layer) and about 85 to 88% from the inner side to the outer side in the thickness direction.
The total thickness of the resin composition (A) layer was 6.5% of the total layer thickness at the (outer layer) position.

Example 8 In Example 6, as the component (A2), a saponified product of a maleic anhydride-modified ethylene-vinyl acetate copolymer [ethylene content 86 mol%, saponification degree of vinyl acetate component 97 mol%, MFR 20g / 10min (190 ℃, load 2160
except that the resin composition (A) was obtained in the same manner and a multilayer container (bottle) was squeezed out in the same manner.
It evaluated similarly.

Example 9 In Example 7, as the component (A2), an ethylene-vinyl acetate copolymer [ethylene content 88 mol%, MFR2
g / 10 minutes (190 ° C, load 2160g)] (A2
-1) and a maleic anhydride modified ethylene-vinyl acetate copolymer [ethylene content 96 mol%, MFR 4 g / 10 min (measured at 190 ° C, load 2160 g), maleic anhydride modified amount 0.4%] (A2 -2) mixture [mixing ratio (A2-1) /
(A2-2) = 75 parts / 25 parts], except that the resin composition (A) was obtained in the same manner and a multilayer container (bottle) was similarly squeezed out and evaluated in the same manner.

Example 10 In Example 4, the blending ratio of EVOH (A1) and saponified ethylene-vinyl acetate copolymer (A2) was adjusted to EVOH (A1).
(A1) 90 parts and ethylene-vinyl acetate copolymer saponified product (A2) 10 parts in the same manner except that the resin composition (A) [acetic acid content in the resin composition (A) is 90 pp
m, sodium acetate content was 60 ppm (sodium conversion), magnesium acetate content was 31 ppm (magnesium conversion), calcium acetate content was 18 ppm (calcium conversion)], and a squeezed multilayer container (bottle) was similarly prepared. And evaluated in the same manner.

Example 11 In Example 5, the blending ratio of EVOH (A1) and saponified ethylene-vinyl acetate copolymer (A2) was changed to EVOH.
(A1) 70 parts and the saponified product of ethylene-vinyl acetate copolymer (A2) 30 parts in the same manner except that the resin composition (A) [the boric acid content in the resin composition (A) is 105 p
pm (boron equivalent), sodium acetate content is 250p
pm (in terms of sodium)], a multilayer container (bottle) was similarly squeezed out and evaluated in the same manner.

Example 12 In Example 6, the blending ratio of EVOH (A1) and saponified ethylene-vinyl acetate copolymer (A2) was changed to EVOH (A1).
(A1) 85 parts and saponified ethylene-vinyl acetate copolymer (A2) 15 parts in the same manner except that the resin composition (A) [acetic acid content in the resin composition (A) is 85 pp
m, sodium acetate content is 90 ppm (sodium conversion), magnesium acetate content is 30 ppm (magnesium conversion), calcium acetate content is 17 ppm (calcium conversion)], and a squeezed multilayer container (bottle) is similarly prepared. And evaluated in the same manner.

Comparative Example 1 A squeezed multilayer container (bottle) was prepared in the same manner as in Example 1 except that the resin composition (A) did not contain the saponified product of the ethylene-vinyl acetate copolymer (A2). , And similarly evaluated.

Comparative Example 2 In Example 1, the squeezed multilayer container was constructed such that the outer low-density polyethylene (B) layer (50 μm) / regrind layer (150 μm) / resin composition (A) layer (20 μm) /
A multilayer container (bottle) was squeezed out in the same manner except that the inner low-density polyethylene (B) layer (50 μm) was used, and the resin composition (A) layer contained about 18 to 26% of the inner to outer side in the thickness direction. The evaluation was performed in the same manner so that the position was reached. The thickness of the resin composition (A) layer was 7.4% of the total layer thickness.

Comparative Example 3 In Example 1, the squeezed multilayer container was constructed such that the outer low-density polyethylene (B) layer (30 μm) / regrind layer (100 μm) / resin composition (A) layer (60 μm) /
A squeezed multilayer container (bottle) was prepared in the same manner except that the inner low-density polyethylene (B) layer (120 μm) was used.
The resin composition (A) layer was evaluated in the same manner so that the position was about 39 to 58% from the inner side to the outer side in the thickness direction. The thickness of the resin composition (A) layer was 19.4% of the total layer thickness.

Comparative Example 4 The composition of the squeezed-out multilayer container in Example 1 was the same as that of the outer low-density polyethylene (B) layer (5 μm) / resin composition (A) layer (10 μm) / regrind layer (150 μm).
/ A multilayer container (bottle) was squeezed out in the same manner except that the inner low-density polyethylene (B) layer (130 μm) was used, and the resin composition (A) layer had a thickness of 94.9 to 98 from the inner side to the outer side. The same evaluation was performed so that the position was 0.3%. The thickness of the resin composition (A) layer was 3.4% of the total layer thickness.

Table 1 shows the evaluation results of the examples and the comparative examples.

[Table 1] Appearance Gas barrier property Delamination strength Squeeze property Reclined property (g / 15 mm) Example 1 ○ 0.005 58 ○ ○ 〃 2 ○ 0.007 54 ○ ○ 〃 3 ○ 0.006 60 ○ ○ 〃 4 ○ 0.005 65 ◎ ○ 〃 5 ○ 0.004 64 ◎ ○ 〃 6 ○ 0.007 61 ◎ ○ 〃 7 ○ 0.006 68 ◎ ○ 〃 8 ○ 0.009 61 ◎ ○ 〃 9 ○ 0.008 47 ◎ ○ 〃 10 ○ 0.004 60 ◎ ○ 〃 11 ○ 0.005 74 ◎ ○ 〃 12 ○ 0.006 57 ◎ ○ Comparative Example 1 △ 0.004 8 × × 〃 2 ○ 0.015 39 × ○ 〃 3 △ 0.003 43 × × 〃 4 〇 0.010 41 × 〇 Note) The unit of gas barrier property is cc / bottle ・ day ・ air

[0115]

The squeezed multilayer container of the present invention has a specific resin composition layer as an intermediate layer and polyolefin resin layers on both sides thereof, and the resin composition layer has a specific position in the thickness direction of the multilayer container. Therefore, it has excellent appearance, gas barrier property, interlayer adhesion, squeeze property, and regrind property, and is used for various packaging applications (in addition to foods, seasonings, fermented foods, oil and fat foods, beverages, cosmetics, pharmaceuticals, detergents, cosmetics). , Industrial chemicals, pesticides, fuels, etc.), specifically, mayonnaise, ketchup, miso, lard, jam, chocolate, butter, margarine, jelly, yogurt, wasabi, mustard, ginger, garlic. Viscous liquid or paste foods such as toothpaste, shampoo, rinse, conditioner, hair dye, seasonings, spices, beverages, makeup Are useful in applications such as pharmaceuticals, it is particularly useful as the contents mayonnaise, ketchup, squeeze multilayered container is at least one selected from the source (squeeze bottle).

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 29/04 C08L 29/04 SF term (reference) 3E065 AA02 BA16 BA17 BA18 BB03 CA09 DA04 DB05 FA03 FA06 FA11 GA01 GA02 GA10 HA01 HA02 HA03 4F100 AK01D AK03A AK03B AK03C AK03J AK06B AK06C AK21A AK21J AK62B AK62C AK66B AK66C AK69A AL01A AL05A BA03 BA04 BA06 BA07 BA10B BA10C BA15 DA01 EH20 GB15 GB16 GB23 JA15B JA15C JA20A JB05A JB06B JB06C JD02 JL11 JL16 JL16D YY00A YY00B YY00C 4J002 BB22X BE03W FD010 FD020 FD070 FD170 FD200 GG01

Claims (9)

[Claims] 1. A resin composition (A) layer containing an ethylene-vinyl acetate copolymer saponified product (A1) and an olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2) as an intermediate layer. In a multi-layered container in which a polyolefin resin (B) layer is arranged on both sides of the layer, all of the resin composition (A) layer is located at 55 to 98% of the inner side to the outer side in the thickness direction of the multi-layered container. A squeezed multi-layer container characterized in that it is arranged in. 2. A content weight ratio (A1 / A) of the saponified ethylene-vinyl acetate copolymer (A1) and the olefin-carboxylic acid vinyl ester copolymer and / or its saponified product (A2).
The squeezed multilayer container according to claim 1, wherein 2) is 50/50 to 99/1. 3. The olefin-carboxylic acid vinyl ester copolymer (A2) is an ethylene-vinyl acetate copolymer having a vinyl acetate content of 3 to 30 mol%. Squeezed multilayer container. 4. The saponified product (A2) of an olefin-carboxylic acid vinyl ester copolymer has an ethylene content of 70-9.
The squeezed multilayer container according to claim 1 or 2, which is a partially saponified ethylene-vinyl acetate copolymer having a vinyl acetate component content of 7 mol% and a saponification degree of 20 to 99.9 mol%. 5. The resin composition (A) is a saponified product of an ethylene-vinyl acetate copolymer (A1) having a water content of 1 to 60% by weight, an olefin-carboxylic acid vinyl ester copolymer and / or a saponified product thereof (A2). 5. A squeezed multilayer container according to claim 1, which is a resin composition obtained by melt-kneading 6. The polyolefin resin (B) has a melt flow rate (MFR) (measured at 190 ° C. and a load of 2160 g) of 0.1 to 2 g / 10 minutes and a density of 0.920 to.
0.930 g / cm ³ low density polyethylene (LDP
E) is a squeezed-out multilayer container according to any one of claims 1 to 5. 7. At least a polyolefin resin (B)
7. The squeezed-out multilayer container according to claim 1, having a laminated structure of layer / resin composition (A) layer / regrind (C) layer / polyolefin resin (B) layer. 8. The squeezed multilayer container according to claim 1, wherein the thickness of the resin composition (A) layer is 1 to 20% of the total layer thickness. 9. The squeezed multilayer container according to claim 1, wherein the content is at least one selected from mayonnaise, ketchup and sauce.