WO2003006535A1

WO2003006535A1 - Molded polyglycolic acid

Info

Publication number: WO2003006535A1
Application number: PCT/JP2002/007006
Authority: WO
Inventors: Junji Nakajima; Kazuyuki Yamane
Original assignee: Kureha Chemical Industry Company, Limited
Priority date: 2001-07-10
Filing date: 2002-07-10
Publication date: 2003-01-23
Also published as: JP2003020344A

Abstract

A polyglycolic acid molding comprising polyglycolic acid as the main component, in which the polyglycolic acid has a melt viscosity of 20 to 500 Pa·s, excluding 500 Pa·s, as measured at a temperature higher by 20°C than the melting point and a shear rate of 100 /sec and which is a molding formed by compression molding, extrusion molding, blow molding, or solution casting molding. Also provided is a multilayered molding having a layer constitution comprising a polyglycolic acid layer and formed on at least one side thereof a thermoplastic resin layer, wherein the polyglycolic acid contained in the layer consisting mainly of the polyglycolic acid has a melt viscosity of 20 to 500 Pa·s, excluding 500 Pa·s, as measured at a temperature higher by 20°C than the melting point and a shear rate of 100 /sec.

Description

Polyglycolic acid moldings Technical field

TECHNICAL FIELD The present invention relates to various polyglycolic acid molded articles formed from a thermoplastic resin material containing polydalicholic acid as a main component, and more particularly, to an excellent fluidity in a molten state and capable of forming a uniform thin film. The present invention relates to a molded product of polyglycolic acid, which is formed using a thermoplastic resin material containing polydalicholate as a main component, which has remarkable biodegradability and can be rapidly composted. The present invention also relates to a multilayer molded article including a layer containing polyglycolic acid as a main component. The molded article and the multilayer molded article of the present invention can be suitably used in a wide range of fields as, for example, compression molded articles, extruded molded articles, oriented films, stretch blow containers, multilayer hollow containers, multilayer films, fibers, and the like. You. Background art

In recent years, the increase of plastic waste has become a major social problem. As one of the solutions to this problem, research and development of biodegradable polymer materials are under way. Among the biodegradable polymer materials, polyglycolic acid has biodegradability (soil breaking property) and gas barrier properties such as oxygen gas barrier property, carbon dioxide gas barrier property, and steam barrier property. Excellent in heat resistance and mechanical strength.

For this reason, various molded articles using polyglycolic acid have been proposed. Specific examples thereof include a polyglycolic acid oriented film (Japanese Patent Application Laid-Open No. H10-31616) and a polyglycolic acid stretched professional container (Japanese Patent Application Laid-Open No. H10-337772). No. Further, a multi-layer hollow container in which a layer formed of polydaricholic acid is disposed on a core layer or the like (Japanese Patent Application Laid-Open No. H10-138371) and a gas barrier uniform composite film (Japanese Patent Application Laid-Open No. H10-809) 90 publication). A molded article formed using these polyglycolic acids is excellent in gas barrier properties, heat resistance, mechanical strength, and the like, and can exhibit excellent properties such as soil breaking property. However, in these molded products, soil disintegration does not proceed sufficiently quickly, and composting requires a relatively long time. In addition, it was difficult to form polyglycolic acid into a uniform thin film, and there was a limit to weight reduction and cost reduction. For this reason, molded products formed using these polyglycolic acids are difficult to disintegrate in the soil in a short period of time to promote composting, and to develop applications in fields where uniform thinning is required. . Disclosure of the invention

An object of the present invention is to provide a thermoplastic resin material containing polydalicholic acid which has excellent fluidity in a molten state, can form a uniform thin film, has remarkable biodegradability, and can be rapidly composted. An object of the present invention is to provide a single-layer or multi-layer molded article formed by using such as, for example, various molded articles such as a compression molded article, an extruded molded article, an oriented film, a stretch blow container, a multilayer hollow container, and a multilayer film.

Conventionally, in order to obtain molded products with excellent physical properties such as mechanical strength by extrusion molding, blow molding, etc., it is necessary to use a temperature 20 ° C higher than the melting point (hereinafter, the temperature is abbreviated as “melting point + 20 ° C”). It was said that it was necessary to use high molecular weight polydaricholic acid having a melt viscosity of 500 Pa · s or more measured at a shear rate of 100 / sec (see the above-mentioned respective publications).

Contrary to the common knowledge of the art, the present inventors have formed various molded articles using polydalicholate having a relatively low melt viscosity, and have excellent fluidity in a molten state, thereby enabling uniform thinning. In addition, they found that the soil collapsed in a relatively short period of time and the composting was quickly performed.

In addition, the melt viscosity of polyglycolic acid is liable to fluctuate when subjected to melt molding, but by measuring the melt viscosity of polydalicholic acid in the molded product, a molded product excellent in the above-mentioned properties can be clearly identified. can do. The present invention is based on these findings. It was completed based on this.

Thus, according to the present invention, the following formula (1)

A molded article mainly composed of polyglycolic acid containing at least 60% by weight of a repeating unit represented by the formula:

(a) when the melt viscosity of polydalicholic acid in the molded product is measured at a temperature 20 ° C. higher than the melting point and at a shear rate of 100 Z seconds, it is not less than 20 Pas and less than 500 Pas; And,

(b) Molded by molding methods including compression molding, extrusion molding, blow molding, or solution casting.

Thus, there is provided a molded article of polydalicholic acid.

Further, according to the present invention, there is provided an oriented film mainly composed of polyglycolic acid containing 60% by weight or more of the repeating unit represented by the above formula (1), wherein the melt viscosity of polydalicholic acid in the oriented film is However, when measured under the conditions of a temperature 20 ° C. higher than the melting point and a shear rate of 100 Z seconds, an oriented film is provided which is not less than 20 Pa's and less than 500 Pa's.

Furthermore, according to the present invention, there is provided a stretch blow container mainly composed of polyglycolic acid containing a repeating unit represented by the above formula (1) in an amount of 60% by weight or more, wherein polydalicholate in the stretch blow container is contained. A stretch blow container having a melt viscosity of 20 Pa's or more and less than 500 Pa * s when the melt viscosity is measured at a temperature 20 ° C. higher than the melting point and a shear rate of 100 Z seconds is provided.

Furthermore, according to the present invention, a layer in which a thermoplastic resin layer is formed on at least one surface of a layer mainly containing polyglycolic acid containing 60% by weight or more of the repeating unit represented by the above formula (1) A multilayer molded article having a constitution, wherein the melt viscosity of polydalicholate in a layer containing the polydalicholate as a main component is higher than the melting point by 20C. A multi-layer molded article having a degree and shear rate of 100 Pa / s or more and less than 500 Pa-s when measured at a shear rate of 100 / sec is provided.

Further, according to the present invention, a layer structure in which a thermoplastic resin layer is formed on at least one surface of a layer mainly containing polyglycolic acid containing the repeating unit represented by the above formula (1) in an amount of 60% by weight or more is provided. When the melt viscosity of polydalicholate in the layer containing polyglycolic acid as a main component is measured at a temperature 20 ° C. higher than the melting point and at a shear rate of 100 Z seconds, the multilayer hollow container has a pressure of 20 Pa * s. Thus, a multilayer hollow container having a pressure of less than 500 Pa * s is provided.

Further, according to the present invention, a layer in which a thermoplastic resin layer is formed on at least one surface of a layer mainly containing polyglycolic acid containing 60% by weight or more of the repeating unit represented by the above formula (1) A multilayer film having a structure, wherein the melt viscosity of polydalicholate in the layer containing polyglycolic acid as a main component is 20 Pa when measured at a temperature 20 higher than the melting point and a shear rate of 100 ns. A multilayer film having a thickness of at least 500 s and less than 500 Pa · s is provided. BEST MODE FOR CARRYING OUT THE INVENTION

1. Polyglycolic acid

The polyglycolic acid of the present invention has the following formula (1)

Or a homopolymer or copolymer containing a repeating unit represented by

The content of the repeating unit represented by the formula (1) in the polyglycolic acid is 60% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more, and the upper limit is 100% by weight. is there. If the content of the repeating unit represented by the formula (1) is too small, the gas barrier properties and heat resistance are impaired.

Polydaricholic acid includes repeating units other than the repeating unit represented by the formula (1). As the position, for example, at least one repeating unit represented by the following formulas (2) to (6) can be contained.

-(2)

(Where, η = 1 ~: L 0, m = 0 ~ 10)

(Where j = 0)

(In the formula,! ^ And shaku are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. K = 2 to 10)

By introducing other repeating units represented by the formulas (2) to (6) in a proportion of 1% by weight or more, the melting point of the homopolymer of polydalicholic acid can be lowered. If the melting point of polydalicholate is lowered, the processing temperature can be lowered, and thermal decomposition during melt processing can be reduced.

In addition, the crystallization rate of polyglycolic acid can be controlled by copolymerization to improve extrusion processability and stretch processability. If the content of the other repeating units in the copolymer is too large, the crystallinity inherent in polyglycolic acid is impaired, It may have an adverse effect on gasparity and the like.

The physical properties such as the melt viscosity and melting point of polydalicholic acid in the present invention described below are measured as the physical properties of polydalicholic acid in the molded product after the melt molding process, unless otherwise specified.

The polyglycolic acid of the present invention is a relatively low molecular weight polymer. The melt viscosity of the polymer can be used as an index of the molecular weight. When the melting point of the polyglycolic acid of the present invention is represented by Tm, the temperature (Tm + 20 ° C.) (that is, a temperature 20 ° C. higher than the melting point and corresponding to a normal melt processing temperature) and shearing Melt viscosity measured at a speed of 100 / sec 7? * Is not less than 20 Pas and less than 500 Pas, preferably 30 to 400 Pa's, More preferably, it is 40 to 350 Pas. When the melt viscosity of the polyglycolic acid is less than 500 Pa · s, the fluidity in the molten state is excellent, a uniform thin film can be formed, and the disintegration in soil is remarkably promoted. When the melt viscosity of polyglycolic acid is less than 500 Pas, the melt processability at high temperatures tends to decrease compared to the case of polydalicholate having a high melt viscosity. By setting the molding temperature low, it is possible to carry out molding processes such as film-forming and stretch-blow molding. Further, when the melt viscosity of polyglycolic acid is low, the melt processing temperature can be lowered, so that thermal deterioration of polydalicholic acid can be prevented.

The melting point Tm of the polyglycolic acid of the present invention is preferably 15 O or more, more preferably 190 C or more, and particularly preferably 210 C or more. The melt enthalpy Δ Δπι of the polyglycolic acid of the present invention is preferably at least 20 JZg, more preferably at least 30 J / g, particularly preferably at least 40 J / g. It is presumed that the crystallinity of polydalicholic acid, whose melting point and melting enthalpy are too low, is lowered due to disorder of the chemical structure in the molecule. Therefore, molded products such as an oriented film and a stretch blow container formed of such polyglycolic acid tend to have low barrier properties and insufficient heat resistance.

The polyglycolic acid of the present invention preferably has a density of its non-oriented crystallized product of 1.5. H

0 g 2Zcm ³ or more, preferably 1. 52 g_ cm ³ or more, particularly preferably 1.5

C I

3 g / cm ³ or more. Polyglycolic acid, whose density is too low, has a chemical structure in the molecule.

C

/

It is presumed that the crystallinity has decreased due to irregularities in the structure. Therefore, molded products such as oriented films and stretch blow containers made of such low-density polydalicholic acid may have low crystallinity and insufficient gas barrier properties, heat resistance, and strength.

2. Method for producing polydalicholate

Polyglycolic acid has the following formula (I)

O

〇

Qu II

H ₂ C. CH. C-C--0 (I)

OH Reigo OH n

OH

Can be synthesized by the dehydration polycondensation of glycolic acid <Also, polyglycolic acid is represented by the following formula (II)

〇

H. C-1 C-1 0 [II]

OR dealcoholization n

OH

(In the formula, R represents an alkyl group. The alkyl group preferably has about 1 to 5 carbon atoms.)

As shown in the above, it can be synthesized by the dealcohol polycondensation of alkyl dalicolate.

Further, polyglycolic acid is represented by the following formula [I I I]

(III)

As shown in the above, it can be synthesized by ring-opening polymerization of glycolide (that is, intermolecular cyclic ester of glycolic acid). Polyglycolic acid converts glycolide (ie, 1,4-dioxane-1,2,5-dione) in the presence of a small amount of a catalyst (eg, a cationic catalyst such as organic tin carboxylate, tin halide, antimony halide, etc.). It is preferred to synthesize by a method of ring-opening polymerization by heating to a temperature of about 12O to about 250 ° C. The ring-opening polymerization is preferably performed by a bulk polymerization method or a solution polymerization method.

In addition, polyglycolic acid can be obtained by a polycondensation method in which glycolic acid or an alkyl glycolate is heated in the presence or absence of a catalyst to dehydrate or remove alcohol. A polycondensation method of desalting using a glycolic acid salt can also be employed. According to these polycondensation methods, polyglycolic acid having a relatively low melt viscosity can be easily obtained.

In order to synthesize a copolymer of polyglycolic acid, in each of the above synthesis methods, as a comonomer, for example, ethylene oxalate (that is, 1,4-dioxane-12,3-dione), lactide, lactone ( For example, jS-propiolactone, β-butyrolactone, pivalolactone, r-butyrolactone, δ-valerolactone,] 3-methyl-δ-valerolactone, ε-force prolactone, etc.), trimethylene force-one-ponate, and 1,3 —Cyclic monomers such as dioxane; hydroxycarboxylic acids such as lactic acid, 3-hydroxypropanoic acid, 3-hydroxybutanoic acid, 4-hydroxybutanoic acid, and 6-hydroxycaproic acid, or alkyl esters thereof; ethylene glycol, 1,4 Aliphatic diols such as monobutanediol and fats such as succinic acid and adipic acid A mixture of substantially equimolar with an aromatic dicarboxylic acid or an alkyl ester thereof; or two or more of these may be appropriately combined with glycolide, glycolic acid, or an alkyl ester of dalicholate to be copolymerized.

The polyglycolic acid copolymer can be synthesized by subjecting polydaricholic acid and another polymer having a repeating unit selected from the above formulas (2) to (5) to a transesterification reaction under heating.

In the ring-opening polymerization method, as the glycolide used as a monomer, a glycolide obtained by a conventional sublimation depolymerization method of oligoglycolic acid can be used. However, those obtained by the “solution phase depolymerization method” disclosed in Japanese Patent Application Laid-Open No. Hei 9-3228481 can be obtained in large quantities with high purity and high yield. This is preferred because

In the solution phase depolymerization method, (1) a mixture containing a glycolic acid oligomer and at least one high-boiling-point polar organic solvent having a boiling point in the range of 230 to 450 ° C is subjected to a normal pressure or a reduced pressure. (2) dissolving the oligomer in the solvent until the residual ratio (volume ratio) of the melt phase of the oligomer becomes 0.5 or less; ) Further heating is continued at the same temperature to depolymerize the oligomer, (4) dimer cyclic ester (ie, glycolide) formed is distilled off together with a high boiling point polar organic solvent, and (5) distillate The glycolide is recovered from

Examples of high boiling polar organic solvents include bis (alkoxyalkyl esters) such as di (2-methoxyethyl) phthalate, alkylene glycol dibenzoates such as diethylene glycol dibenzoate, and benzyl butyl dibutyl phthalate. Examples thereof include aromatic phosphoric acid esters such as aromatic carboxylic acid esters and tricresyl phosphate, etc. The oligomer is usually used in a ratio of 0.3 to 50 times (weight ratio) to the oligomer. If necessary, polypropylene glycol, polyethylene glycol, tetraethylene glycol, or the like can be used as a solubilizing agent for the oligomer together with the high boiling point polar organic solvent. The depolymerization temperature of the glycolic acid oligomer is usually 230 ° C. or higher, preferably 230 ° C. to 320 ° C. The depolymerization is carried out under normal pressure or reduced pressure, but it is preferable to carry out depolymerization by heating under reduced pressure of 0.1 to 9.0 kPa (1 to 900 mbar).

3. Thermoplastic resin material

In the present invention, various molded articles, for example, compression molded articles such as trays, extruded molded articles, oriented films, stretched bottles, multi-layer molded articles, are manufactured using thermoplastic resin materials containing polyglycolic acid as a main component. , Multi-layer hollow container, and multi-layer film Specifically, a thermoplastic resin material containing a specific polyglycolic acid is used as a raw material.

As the thermoplastic resin material, polydalicholate nitresin alone can be used. Further, as the thermoplastic resin material, a composition in which an inorganic filler, another thermoplastic resin, a plasticizer, and the like are blended with polydaricholic acid within a range not to impair the object of the present invention can be used. The amount of the inorganic filler, other thermoplastic resin, plasticizer, and the like is appropriately selected from the viewpoints of gas barrier properties, biodegradability, and uniform thin film formation. When other components are blended with polydalicholic acid, the proportion of polydalicholic acid in the thermoplastic resin material is usually at least 50% by weight, preferably at least 70% by weight, more preferably at least 90% by weight.

The amount of the inorganic filler is preferably 0 to 30 parts by weight, more preferably 0 to 10 parts by weight, and particularly preferably 0 to 5 parts by weight, based on 100 parts by weight of the polyglycolic acid. When the inorganic filler is blended, the lower limit is preferably 0.01 part by weight, more preferably 0.05 part by weight.

The amount of the other thermoplastic resin is preferably 0 to 50 parts by weight, more preferably 0 to 30 parts by weight, based on 100 parts by weight of the polyglycolic acid. When other thermoplastic resins are blended, the lower limit is preferably 0.05 parts by weight.

The blending amount of the plasticizer is preferably 0 to 50 parts by weight, more preferably 0 to 30 parts by weight, and particularly preferably 0 to 10 parts by weight with respect to 100 parts by weight of polyglycolic acid. . When a plasticizer is added, the lower limit is preferably 0.01 part by weight, more preferably 0.05 part by weight. However, when the polyglycolic acid used in the present invention has a sufficiently low melt viscosity, it is often unnecessary to add a plasticizer. Inorganic fillers include alumina, silica, silica-alumina, zirconia, titanium oxide, iron oxide, boron oxide, calcium carbonate, calcium silicate, phosphoric acid, calcium sulfate, magnesium carbonate, magnesium silicate, magnesium phosphate. , Magnesium sulfate, kaolin, talc, myriki, ferrite, carbon, silicon, gallium nitride, molybdenum disulfide, glass, inorganic substances such as potassium titanate 4. Molded object

Using the thermoplastic resin material containing polyglycolic acid of the present invention, trays of various shapes and deep drawn products can be formed by molding methods including compression molding (press molding), extrusion molding, blow molding, and solution casting. An arbitrary molded product such as a sheet, a film, a fiber (single layer or multilayer such as yarn and composite yarn), a hollow container and the like can be formed. For example, a container such as a tray can be formed by compression molding.

Extrusion includes stretch film molding, inflation molding, and T-die molding in addition to extrusion molding of sheets and unstretched films. Extrusion includes the case where an extruded product is subjected to secondary molding. For example, a sheet obtained by extrusion molding can be further subjected to secondary forming such as vacuum forming and pressure forming. Among these molded products, compression molded products, oriented films, and stretched professional containers are preferred.

Further, in the present invention, a multilayer molded article having a layer configuration in which a thermoplastic resin layer is formed on at least one surface of a layer formed of a thermoplastic resin material containing polyglycolic acid can be molded. Examples of such a multilayer molded product include a multilayer sheet, a multilayer hollow container, and a multilayer film.

Among the molded products, in the oriented film, the stretch blow container, the multilayer hollow container, and the multilayer film, the gas barrier property of polydalicholic acid can be sufficiently exhibited. In addition, the layer (the film, the body of the container, the core layer of the multilayer hollow container or the multilayer film, etc.) made of the thermoplastic resin material containing polyglycolic acid can be uniformly thinned.

In the soil disintegration test of the polyglycolic acid molded product of the present invention, the ratio of the weight (X) to the initial weight (y) after being buried in the soil for 6 months [(xZy) X10 0 () 3 exhibits excellent soil disintegration of preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

5. Oriented film 11 powder, whiskers, fibers and the like. These inorganic fillers can be used alone or in combination of two or more.

Other thermoplastic resins include, for example, homopolymers and copolymers of lactic acid, homopolymers and copolymers of ethylene oxalate, homopolymers and copolymers of ε-force prolactone, and polysuccinate esters , Polyhydroxybutanoic acid, hydroxybutanoic acid-hydroxyvaleric acid copolymer, cellulose acetate, polyvinyl alcohol, starch, polyglutamic acid ester, natural rubber, polyethylene, polypropylene, styrene butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, Examples include polyethylene methacrylate, polystyrene, styrene-butadiene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, ABS resin, MBS resin, and ethylene-vinyl alcohol copolymer.

Examples of the plasticizer include phthalic acid esters such as di (methoxyethyl) phthalate, dioctyl phthalate, getyl phthalate, and benzyl butyl phthalate; benzoic acids such as dimethyl glycol dibenzoate and ethylene glycol dibenzoate; Esters: aliphatic dibasic acid esters such as octyl adipate and octyl sebacate; aliphatic tribasic acid esters such as triptyl acetyl citrate; phosphate esters such as dioctyl phosphate and tricresyl phosphate; epoxidized soybean oil and the like Epoxy plasticizers; polyalkylene glycol esters such as polyethylene glycol sebacolate and polypropylene glycol laurate; and the like.

In the present invention, if necessary, various additives such as a heat stabilizer, a light stabilizer, a moisture proof agent, a waterproof agent, a water repellent agent, a lubricant, a release agent, a coupling agent, a pigment, and a dye may be added to the thermoplastic resin material. Can be included in the ingredients. These various additives are used in an effective amount according to the purpose of use. The thermoplastic resin material is supplied to a kneading extruder in the usual manner with polyglycolic acid alone or with at least one of other components such as polyglycolic acid, an inorganic filler, a thermoplastic resin, a plasticizer, and various additives. The cylinder temperature is Tm to 255 ° C (usually 150 to 255 ° C), melt-kneaded, extruded into strands, cooled and cut into pellets. The oriented film of the present invention can be produced by melt-extruding the above-mentioned polyglycolic acid netoresin or a composition containing the polyglycolic acid, stretching and orienting, and, if necessary, heat setting. As the melt film forming method, a method such as uniaxial stretching by a flat die method, sequential biaxial stretching, and simultaneous biaxial stretching, or inflation biaxial stretching by a circular die method can be employed. Preferred methods include the following methods.

(1) Roll method: A method of manufacturing a uniaxially oriented flat film by stretching a sheet melt-extruded using a T-die through a stretching roll in the machine direction (MD).

(2) Tenter method: The sheet extruded using a T-die is oriented in the machine direction (MD) by a drawing port, and then oriented in the transverse direction (TD) using a tenth unit. A method for producing an axially oriented flat film.

(3) Inflation method: melt extruded into a tube using a ring die for inflation, quenched to a temperature below the crystallization temperature ( _TCl ), pressurize gas into the tube, expand the tube. How to stretch. By stretching in the longitudinal direction between the nip rolls by this method, a biaxially stretched film can be obtained. As a method of cooling after melt extrusion into a tube, there are a method of airing and a method of immersion in cold water. Among these methods, a particularly preferred method for producing an oriented film is as follows.

In the roll method, a thermoplastic resin material is supplied to an extruder equipped with a T die, extruded into a sheet at a temperature in the range of Tm to 255 ° C (usually 150 to 255 ° C), and immediately cooled with a cooling drum or refrigerant. Quenching to a temperature below Tci, preferably below the glass transition temperature (Tg) using

Through the stretching port in the temperature range (normally 30 to 120 ° C), preferably Tg to (Tg + 10 ° C) (normally 30 to 48 ° C), and 1 times the MD. Stretch at a stretch ratio of 20 times or less (preferably 2 to 10 times). Orient, and if necessary, for 1 second in a temperature range of TC i ~ (at Tm + 10) (usually 70 to 240 ° C). Manufacturing a uniaxially oriented flat film by heat setting under fixed length or tension for 3 hours (preferably 3 seconds to 0.5 hour) Can be. If the sheet extrusion temperature from the T-die exceeds 255 ° C, the polymer will be decomposed, and the resulting sharp decrease in molecular weight and foaming will easily occur, and a sheet-like material suitable for the next stretching process will be obtained. It may disappear. When the stretching temperature exceeds T ci, the sheet material is almost crystallized, and there is a possibility that the stretching orientation can hardly be performed. The obtained uniaxially oriented film can be easily split into yarns by further opening in the width direction.

In the Tenyuichi method, a thermoplastic resin material is supplied to an extruder equipped with a T die, extruded into a sheet at a temperature of Tm to 255 (usually 150 to 255 ° C), and a cooling drum, refrigerant, etc. Quenched to Tc i or lower, preferably to Tg or lower, and then, similarly to the roll method, at a temperature of Tg to TC i (usually 30 to 120 ° C.), preferably T g to (Tg + 10 ° C.) In a temperature range of (normally 30 to 48 ° C), the film is stretched through a stretching roll into a MD at a stretching ratio of more than 1 to 10 times or less (preferably 2 to 8 times), and then Tg to Tc (normally 30 to 120 ° C). ° C), preferably in the temperature range of Tg ~ (Tg + 20 ° C) (usually 30-58 ° C), with a draw ratio of more than 1 time to TD and 10 times or less (preferably 2-8 times) stretched, at a constant length or under tension optionally under, T _{C l} a temperature of ~ (Tm + 10 ° C) 1 second to 3 hours (in the usual 70 to 240) (preferably 3 seconds to 30 minutes) By heat setting A biaxially oriented flat film can be manufactured.

In the inflation method, a thermoplastic resin material is fed to an extruder equipped with an inflation ring die and melt-extruded into a tube at a temperature of Tm to 255 ° C (usually 150 ° C to 255 ° C). immediately T _{C l} below, preferably rapidly cooled to below Tg, then, Tg~TC i (usually 30~: L 20 ° C), preferably Tg~ (T g + 10 ° C ) ( normal 30-48) In the above temperature range, blow rate is blown so that the blow ratio is more than 1 time and 10 times or less (preferably 2 to 8 times), and the take-off speed is 0.5 to 100 mZ min (preferably 1 to 50 mZ). Min) and take over the Ep-roll while controlling the MD magnification to be more than 1x and 10x or less (preferably 2-8x), and if necessary, the temperature of the temperature (Tm + 10) (Usually 70 ~ By heating and fixing at 240 ° C) for 1 second to 3 hours (preferably 3 seconds to 0.5 hour) at a fixed length or under tension, a tubular biaxially oriented film can be produced. .

The two surfaces of the oriented film of the present invention are combined, and using a sealer, at a temperature of (Tm−20 ° C.) to (Tm + 100 ° C.), preferably at a temperature of Tm to (Tm + 50 V), usually 0 The bag can be manufactured by heat or melt sealing for 0.1 to 100 seconds, preferably 0.1 to 20 seconds. As a sealer, a hot knife sealer, an impulse sealer, a high frequency sealer, an ultrasonic sealer, or the like can be used.

In each of the methods for producing an oriented film of the present invention, a film which has been subjected to stretching and orientation alone and has not been subjected to heat setting is a heat-shrinkable film having a high heat shrinkage.

The thickness of the oriented film of the present invention is usually 1 to 500/111, preferably 3 to 300 m, more preferably 5 to 200 zm. Even if the oriented film of the present invention is formed as a very thin film having a thickness of 40 m or less, the variation in thickness is small, and

! Shapes are possible.

Specifically, when the set thickness at the time of forming the oriented film is measured as 25 m, the variation (R%) from the set thickness is less than 30%. In addition, when the measured thickness of the oriented film at the time of molding is 15 m, the variation (R%) from the set thickness is 30% or more and less than 70%. When the thickness of the oriented film during molding was set to be 40 / m and measured, the variation (R%) from the set thickness was less than 10%.

The oriented film of the present invention is a soil-disintegrable film having a low environmental load. That is, when the oriented polyglycolic acid film of the present invention is buried in soil at a depth of 10 cm, it usually breaks down within six months and loses its original shape. For example, in the case of a conventional polylactic acid film, the glass transition temperature (Tg) is too high, so that there is a problem that composting is difficult under normal conditions. In contrast, the oriented film of the present invention is formed from polydalicholic acid having a not so high Tg. Therefore, composting under normal conditions is possible. In addition, the rate of disintegration in soil is significantly higher than that of a conventional oriented film obtained using polydalicholic acid having a high melt viscosity.

In the oriented film of the present invention, the one without an inorganic filler or the one with a small amount of the inorganic filler is almost colorless, has high transparency, and has an extremely low haze value. By using a thermoplastic resin material containing a specific polyglycolic acid, it is possible to obtain an oriented film having a very low oxygen permeability. More specifically, according to the present invention, the oxygen permeability (measured at a temperature of 23 ° C. and a relative humidity of 80%; converted to a thickness of 25 m; in accordance with JIS K-7126) is usually 50 cmVm ² · day. · It is possible to obtain an oriented film having a high barrier property of not more than a tm, preferably not more than 30 cmVm ² -day-atm, more preferably not more than 10 cmVm ² · day · atm.

The oriented film of the present invention is also excellent in carbon dioxide gas barrier properties, and has a carbon dioxide gas permeability (measured at a temperature of 23 ° C and a relative humidity of 80%; converted to a thickness of 25 ^ m; compliant with JIS K-7126). Usually, it is 300 cm ³ / m ² · day · atm or less, preferably 100 cmVm ² · day · atm or less, more preferably 30 cmVm ² · day · atm or less. The oriented film of the present invention has a good water vapor barrier property and a moisture permeability (measured at a temperature of 40 and a relative humidity of 90%; converted to a thickness of 25 xm; in accordance with JIS K-0280). m ² · day or less, preferably 50 g / m ² · day or less, more preferably 30 g / m ² · day or less. The oriented film of the present invention can be used for various purposes by itself or after being subjected to a moisture-proof coat or a moisture-proof laminate. This oriented film can be used after being formed into a bag-like molded body. The oriented film of the present invention has features such as high gas barrier properties, heat shrink resistance, and high transparency.

According to the present invention, an oriented film having a low heat shrinkage of usually 30% or less, preferably 20% or less, more preferably 10% or less is obtained. be able to. Such low heat shrinkage film is used for high temperature Suitable for applications such as wrap films used in microwave ovens, trays, containers for instant foods to be infused with hot water, retort food packaging materials requiring high-temperature sterilization, and medical device packaging materials. .

The oriented polyglycolic acid film of the present invention can be easily formed into a thin film. However, a thin oriented film can be used for winding and rewinding operations during film production and processing, or during use and rewinding operations when used for tapes. Alternatively, the magnitude of the friction between the metal surfaces of the film becomes a problem. If the friction is too high, the film may break or wrinkle during the winding and rewinding operations, making these operations difficult. To 100 parts by weight of the specific polyglycolic acid, 0.01 to 5 parts by weight, preferably 0.02 to 3 parts by weight, more preferably 0.03 to 2 parts by weight of the inorganic filler of the powdered strip is used. By using a thermoplastic resin material contained in a proportion of 0.3 parts by mass, the coefficient of dynamic friction between the film and the film / k (23) is 0.35 or less, preferably 0.33 or less, more preferably 0. It is possible to obtain a slippery film of 30 or less.

An unstretched film was prepared using a thermoplastic resin material containing 0.5 to 100 parts by weight of a powdery inorganic filler with respect to 100 parts by weight of polydalicholic acid. When the film is stretched in a uniaxial or biaxial direction so as to be 3 times or more, preferably 4 times or more, an oriented film excellent in printability and easily printing ink can be obtained.

Applications of the oriented film of the present invention include, for example, food packaging, medical equipment packaging, wrap film, western packaging, doll packaging, fresh packaging, vegetable packaging, egg pack, cushioning, multi-film, Carrier bags, garbage bags, sanitary wrapping materials, disposable diapers, adhesive tape, magnetic tape, floppy (R) disks, microwave wrap films, retort food wrapping materials, and instant food wrapping materials. The unheated oriented film can be used as a heat-shrinkable film. Split yarn can be used as a stringing material for loading and agricultural purposes. ,

18

6. Stretch blow container

The stretch blow container of the present invention is obtained by molding a thermoplastic resin material comprising a polydalicholate neat resin having a specific physical property or a composition containing the polydalicholate at a resin temperature of Tm to 255 ° C. A preform in a substantially amorphous state is prepared, and the preform is heated to a resin temperature of (glass transition temperature of polyglycolic acid Tg + 70 ° C) or lower, and exceeds 1 times in the longitudinal direction, and 10 times. At the same time or successively, air is blown into the container to blow-mold it into a hollow container having a blow ratio of 1.5 to 10 and, if necessary, furthermore, the crystallization temperature of polydaricholic acid Tc to (Tm + 1 (0 ° C.) for 1 second to 30 minutes.

The resin temperature during preform (parison) molding is in the range of melting point Tm to 255 ° C. The Tm of polydalicholate is about 220 ° C in the case of a homopolymer.However, by copolymerizing with a comonomer such as ethylene oxalate, lactide, lactones, trimethylene monoponate, and 1,3-dioxane, Generally lower. Therefore, the resin temperature at the time of preform molding is usually 150 to 255 ° C, preferably 190 to 25 ° C, and more preferably 200 to 24 ° C. If the resin temperature exceeds 255 ° C, polydalicholate becomes susceptible to thermal decomposition, making it impossible to obtain a satisfactory preform.

The preform is formed as a substantially amorphous preform. If the preform is in a crystalline state, in the next stretching step, the tension at the time of stretching increases, and stretching becomes difficult. A preform in a substantially amorphous state can be obtained by rapidly cooling the molten resin.

The temperature condition of the stretching pro-forming is (Tg + 70 :) or less. If the temperature of the resin at the time of stretching is higher than (Tg + 70 ° C), the mobility of the polymer molecular chains is too active, and even if stretch blowing is performed, the stretched orientation state is immediately relaxed and the orientation is reduced. It may disappear or be significantly reduced.

In the case of the cold parison method, after the parison obtained by injection molding or extrusion molding is once cooled and solidified, the resin temperature is Tg to (Tg + 7 Re-heat so as to be in the range of 0). In the case of the hot parison method, the parison obtained by injection molding or extrusion molding is cooled, but stretch blow-molded while the resin does not solidify. In other words, when the preform is a hot parison, the preform is melt-molded at a temperature of Tm to 255 ° C, then quenched to a temperature of (Tg-30 ° C) to (Tg + 70 ° C), Stretch-blow molding is performed while is not solidified. Even if the melt-formed preform is rapidly cooled and supercooled to a temperature lower than Tg, a stretch-blow container can be manufactured by immediately performing stretch-blow molding while the resin does not solidify.

The Tg of polyglycolic acid is about 38 ° C in the case of a homopolymer, but by copolymerizing with comonomers such as ethylene oxalate, lactide, lactones, trimethylene glycol and 1,3-dioxane, Its value fluctuates. Therefore, the resin temperature at the time of elongation forming is (Tg + 70 ° C) or less, preferably 30 to 100 ° C, and more preferably 35 to 90.

The preform is stretched more than 1 times and 10 times or less in the machine direction. In the case of a bottomed parison, it is usually stretched using a stretching rod. In the case of a hollow pipe-shaped parison, both ends are held in a holder and stretched in the longitudinal direction (longitudinal direction). The extension ratio in the longitudinal direction is preferably about 1.5 to 5 times. The blow ratio is usually 1.5 to 10, preferably 1.8 to 9, and more preferably 2.0 to 8. If the blow ratio is less than 1.5, the orientation of the molecular chains is insufficient, the crystallinity is insufficient, and harmful coarse spherulites are generated, and sufficient tensile strength cannot be exhibited. Properties, heat resistance, and transparency may also be insufficient. The blow ratio refers to the ratio of the diameter (maximum diameter) of the container to the diameter of the parison formed in the container in blow molding. The step of blowing by blowing air is performed simultaneously with or after the longitudinal stretching (sequentially).

In the final step of stretch blow molding, if necessary, at a temperature of TC i ~ (Tm + lO) (usually 70 to 240 ° C) for 1 second to 30 minutes (usually 2 seconds to 10 minutes) Heat Fix it. High burr whose body side wall is fully oriented by stretching Yield, high elasticity, high strength, heat resistant stretch blow container can be obtained. In contrast, in the conventional extrusion blow molding method that does not involve stretching orientation (for example, Japanese Patent Application Laid-Open No. Hei 6-2878785) or the injection blow molding method, the side wall of the body is not formed when the hollow container is molded. Since little or no stretching orientation occurs, the resulting hollow container has unsatisfactory barrier properties, mechanical properties, and heat resistance.

More specifically, the stretch blow molding method that can be employed in the present invention includes the following various methods.

(1) Injection / stretch blow two-stage method

The thermoplastic resin material containing polydalicholic acid is supplied to an injection molding machine, and is injection-molded in a mold at a resin temperature of Tm to 255 ° C to form a bottomed parison, and then cooled and solidified. A preform made of a cold parison having a resin temperature of less than Tg, and then the preform was reheated to a resin temperature of Tg ~ (Tg + 70 ° C) and then placed in a blow mold. It is moved and stretched by a stretching rod in the longitudinal direction by more than 1 times and 10 times or less, and simultaneously or sequentially blows air to blow-mold into a hollow container with a blow ratio of 1.5 to 10 and, if necessary And heat-fix.

(2) Injection / stretch blow 1-stage method

The thermoplastic resin material containing polyglycolic acid is supplied to an injection molding machine, injection molded in a mold at a resin temperature of Tm ~ 255 ° C to produce a bottomed parison, and then cooled. (T g + 70 ° C) A preform made of unsolidified hot parisone having a resin temperature of not more than (T g + 70 ° C), and then moving the preform into a blow-molding mold, and moving the preform in a longitudinal direction with a stretching rod. At the same time or successively, air is blown at the same time or sequentially, blow-molded into a hollow container with a ratio of 1.5 to 10 and heat-fixed if necessary. In this method, the preform moves to the professional molding process while maintaining the preheating of the injection molding. A hot parison temperature adjustment step may be added.

(3) Extrusion and stretch blow two-stage method (Part 1)

A thermoplastic resin material containing polydalicholic acid was fitted with a parison die. It is supplied to an extruder, extruded at a resin temperature of Tm to 255 ° C to produce a hollow pipe, cooled and solidified to a temperature below Tg, and cut into a fixed length to form a cold parison preform. Then, after reheating the preform to a resin temperature of Tg ~ (Tg + 70 ° C), both ends thereof are held in a holder and stretched in the length direction by more than 1 times and stretched to 10 times or less, Then, after pinching off one end to make it bottomed, it is moved into a blow molding die, blown with air, blow-molded into a hollow container with a blow ratio of 1.5 to 10, and heat-fixed if necessary. .

(4) Extrusion and stretching professional two-step method (Part 2)

A thermoplastic resin material containing polyglycolic acid is fed to an extruder equipped with a parison die, extruded at a resin temperature of Tm to 255 ° C to form a hollow pipe, and then cooled to a temperature below Tg. It is cooled and solidified, cut to a certain length to obtain a preform made of cold parison, and then the preform is reheated to a resin temperature of Tg to (Tg + 70 ° C), and one end of the preform is pinched off. It is moved to the bottom, then it is moved into the mold for professional molding, and it is stretched to more than 1 times and 10 times or less in the longitudinal direction by the stretching rod, and air is blown simultaneously or sequentially, and the blow ratio is 1.5 to 10 Blow molding into hollow containers and heat-fixing as necessary.

(5) Extrusion and stretch blow one-step method (Part 1)

A thermoplastic resin material containing polyglycolic acid is supplied to an extruder equipped with a parison die, and is extruded at a resin temperature of Tm to 255 ° C to produce a hollow pipe. (Tg + 70t) After cooling to the following resin temperature and cutting into a fixed length to form a preform made of hot parison, both ends are held in a holder and stretched in the length direction by more than 1 time and 10 times or less, and then After pinching off one end to make it bottomed, it is moved into a blow molding die, blown with air, blow-molded into a hollow container having a blow ratio of 1.5 to 10, and heat-fixed if necessary. A hot parison temperature adjustment step may be added.

(6) Extrusion and stretch blow one-stage method (Part 2)

A thermoplastic resin material containing polydalicholic acid was fitted with a parison die. Feed to the extruder, Τπ! After extruding at a resin temperature of ~ 255 ° C to produce a hollow pipe, it is cooled to a resin temperature of (Tg + 70 ° C) or less, cut to a certain length, and cut into a plastic parison. After reforming, one end is pinched off to make it bottomed, and then moved into the blow molding die and stretched by a stretching rod to more than 1 times and 10 times or less in the longitudinal direction, and simultaneously or simultaneously Air is blown in one by one to blow-mold into a hollow container having a blow ratio of 1.5 to 10 and heat-fix if necessary. A hot parison temperature adjustment step may be added.

According to the present invention, a stretch blow container having an internal volume of 25 ml or more can be obtained, but the internal volume can be appropriately determined according to the purpose of use. Usually, at the time of stretch blow molding, the stretch blow container for forming the mouth and the bottom preferably has a shape having a flat portion at the bottom so that it can stand upright independently. However, even those that do not have a flat part at the bottom, such as a round bottom, can be erected by providing an annular band (a kind of hook).

In the stretch blow container of the present invention, even when the thickness of the body is formed to be thin, variation in the thickness of the body can be suppressed to a small value. Specifically, a stretch blow container having a variation (R) from the set thickness of less than 30% can be obtained when the set body thickness at the time of molding the stretch blow container is measured as 100. In addition, when the set body thickness at the time of forming the stretch-blow-out container is measured at 50 zm, a stretch-blow container having a variation (R%) from the set thickness of 30% or more and less than 70% is used. Obtainable. When the thickness of the body portion set at the time of molding of the stretch blow container is increased to 200 m and measured, a stretch blow container having a variation (R%) from the set thickness of less than 10% can be obtained.

The stretch blow container of the present invention is a molded product having a low environmental load and disintegrating in soil. That is, when the stretch blow container made of polydalicholic acid of the present invention is buried in soil at a depth of 10 cm, it usually collapses within six months and loses its original shape. In the stretching container of the present invention, the one in which the inorganic filler is not added or the one in which the amount of the inorganic filler is small is almost colorless, has high transparency, and has an extremely low haze value. No.

The stretch blow container of the present invention can exhibit gas barrier properties, heat resistance, mechanical properties, and the like by sufficiently stretching and orienting the molecular chains of the polymer on the body side wall during stretch blow molding.

According to the present invention, it is possible to obtain a stretch blow container having high oxygen and carbon dioxide gas barrier properties. In the stretch blow container of the present invention, the oxygen permeability (the temperature

(Measured at 23 ° C and relative humidity of 80%, converted to a thickness of 50 m) is usually 150 cm ³ / m ² · day · atm or less, preferably 50 cmVm ² · day · atm or less, more preferably 20 cmVm ² ■ d ay · a tm or less. The stretchable mouthpiece of the present invention preferably has a carbon dioxide gas permeability of the body side wall (measured at a temperature of 23 ° C and a relative humidity of 80%, and converted to a thickness of 50 xm) of 300 cmVm ² · day · atm or less. Is at most 100 cmVm ² · day · atm, more preferably at most 30 cmVm ² · day · atm. Stretching Pro first container of the present invention, the moisture permeability of the barrel sidewall (temperature 40 ^D C, measured at a relative humidity of 90%, the thickness 50; terms of tim) is usually 100g / m ² · d ay less, preferably 50 g / m ² · day or less, more preferably 30 g Zm ² · day or less.

The stretched professional container of the present invention may be used as it is or after having been subjected to a moisture-proof coating, moisture-proof laminating, etc., for example, as a container for carbonated drinking water, soft drink, seasoning, edible oil, liquor, fruit juice, etc. It can be replaced with a general-purpose parier hollow container such as.

The stretch blow container of the present invention has high elasticity on the body side wall, so even if the wall thickness is reduced to about half that of the conventional hollow container, the stretch blow container has a strong stiffness and does not easily deform even when the contents are filled. . Therefore, the economic effect of reducing the wall thickness due to this high elasticity is extremely large.

According to the present invention, it is possible to obtain a stretch blow container having excellent heat resistance. The heat shrinkage (130 ° C, 10 minutes) of the body side wall of the stretch blow container of the present invention is usually

30% or less, preferably 20% or less, more preferably 10% or less You. Such a low heat shrinkage hollow container is suitable as a container for foods such as seasonings that require high-temperature sterilization. In addition, hollow containers with a heat shrinkage rate of more than 30% may be problematic when used at a high temperature of 130 ° C or higher because the deformation becomes too large.

The stretch blow container of the present invention can be used for various applications by utilizing its features such as high barrier properties, heat resistance, transparency, and mechanical strength. Specific examples include containers for carbonated drinking water, soft drinks, edible oils, fruit juices, liquors, etc .; containers for drinking water, detergents, cosmetics; containers for seasonings requiring high-temperature sterilization, and baby bottles. . 7. Multi-layer hollow container

The multilayer hollow container of the present invention comprises at least one thermoplastic resin layer (hereinafter sometimes referred to as a “base resin layer”), a polydalicholate nitrate resin having specific physical properties, or a composition containing the polydalicholate. It is a multi-layer hollow container having a layer (hereinafter sometimes simply referred to as “PGA layer”) formed of a thermoplastic resin material, and has gas barrier properties. If necessary, an adhesive layer can be interposed between the respective layers.

The thickness of the entire side wall of the multilayer hollow container of the present invention is usually 5 m to 5 mm, preferably 1001 to 3111111, and more preferably 20 m to 2 mm. If the thickness is too small, the mechanical strength is insufficient. If the thickness is too large, when used as a hollow container, the quality is excessive, the cost is high, and it is not preferable from the viewpoint of productivity and economy.

The basic layer configuration of the multilayer hollow container of the present invention is as follows. However, the adhesive layer is omitted. Further, a thermoplastic resin material containing polyglycolic acid is abbreviated as PGA.

(1) Thermoplastic resin / PG A

(2) Thermoplastic resin 1 ZPGAZ thermoplastic resin 1

(3) Thermoplastic resin 1 ZPGA / thermoplastic resin 2

The multilayer hollow container of the present invention has various requirements as long as it has the basic layer configuration described above. Depending on the characteristics, the same or different resin layer may be additionally laminated (for example, thermoplastic resin / PGA / PGA). The method for forming a multilayer of the thermoplastic resin layer and the polyglycolic acid layer is not particularly limited. For example, various processing methods such as a method of laminating by a co-extrusion method or a co-injection method can be adopted.

In the multilayer hollow container of the present invention, the thermoplastic resin other than PGA used for the thermoplastic resin layer includes, for example, very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), low density polyethylene ( LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), polypropylene (PP), ethylene 'propylene rubber (EPM), ethylene' vinyl acetate copolymer (EVA), ethylene acrylate copolymer ( Polyolefins such as EEA) and Ionoma I (I〇); Polyesters such as polyethylene terephthalate (PET) and polyethylene naphtholate (PEN); Polystyrene (PS), high impact polystyrene (HI PS), styrene butadiene · Polystyrene resins such as styrene block copolymer (SBS) and hydrogenated SBS (ie SEBS); rigid Polyvinyl chloride (PVC) based resins such as polyvinyl chloride and soft polyvinyl chloride, polycarbonate (PC), polyamide (PA), polyurethane (PU), ethylene vinyl alcohol copolymer (EVOH), polyvinylidene chloride Resin (PVDC). As other thermoplastic resins having a small environmental load, for example, polylactic acid, polysuccinate, polyprolactone and the like are preferable.

In the multilayer hollow container of the present invention, these thermoplastic resin layers are used as a single layer or a multilayer. It is desirable in terms of processability, economical efficiency, and the like, that the thermoplastic resin layer has a range of usually 4 to 5 mm, preferably 10 / im to 3 mm, and more preferably 20 to 2 mm.

In the present invention, an adhesive layer can be interposed between the thermoplastic resin layer (base resin layer) and the polyglycolic acid layer in order to enhance the adhesiveness between the layers. Examples of the adhesive used for the adhesive layer include carboxylated polyolefin and epoxidized polyolefin. Examples include polymers such as olefin, ethylene-pinyl acetate copolymer, ionomer, polyurethane, epoxy resin, SBS, SEBS, polychloroprene, styrene / butadiene copolymer rubber (SBR), and natural rubber (NR). Carboxylated polyolefin is a polyolefin obtained by modifying a polyolefin with an unsaturated acid monomer such as acrylic acid, methacrylic acid, or maleic anhydride to introduce a carboxyl group. The introduction of the hydroxyl group may be carried out by either a copolymerization method or a grafting method. Further, an unsaturated acid monomer may be used in combination with a vinyl monomer such as methyl acrylate, acrylate or vinyl acetate.

The epoxidized polyolefin is a polyolefin obtained by modifying a polyolefin with an epoxy group-containing monomer such as glycidyl methacrylate to introduce an epoxy group. The epoxy group may be introduced by a copolymerization method or a grafting method. Further, the above-mentioned epoxy group-containing monomer may be used in combination with a vinyl-based monomer such as methyl acrylate, acrylate or vinyl acetate. Of these, olepoxylated polyolefin and ethylene / vinyl acetate copolymer are particularly preferred from the viewpoint of adhesiveness and processability. The thickness of the adhesive layer is usually 5 m to 2 mm, preferably 2 m to 1 mm, more preferably 3π! It is in the range of 0.5 mm. If the thickness is less than 0.5 tm, the adhesiveness may be insufficient. If the thickness exceeds 2 mm, it is costly and disadvantageous from an economical point of view.

In the multilayer hollow container of the present invention, a layer (PGA layer) made of a thermoplastic resin material containing polydalicholic acid is disposed to provide a multilayer hollow container having excellent gas barrier properties such as oxygen gas barrier property and carbon dioxide gas barrier property. Can be obtained. The thickness of the PGA layer is usually 1 to 30 mm, preferably 3 to 20 m. In the multilayer hollow container of the present invention, it is preferable that the PGA layer is disposed on the core layer. In this case, the PGA layer has a uniform thickness of 10 zm or less, and even a thin thickness of about 3 to 5 m. Thick layers can be formed.

Specifically, when the set thickness of the layer containing polydalicholate as a main component at the time of molding a multilayer hollow container was measured at 5 m, the variation (R%) from the set thickness was 20%. It can be less than 0%. The same applies when the set thickness is 3 m. By making the melt viscosity of the polyglycolic acid sufficiently small (for example, less than or equal to lOPOP's), the variation (R%) from the set thickness can be made less than 100%. If the melt viscosity of polydalicholate is sufficiently low and the thickness of the layer mainly composed of polydalicholate during molding is 10 im, the variation (R) from the set thickness is 50%. It can also be less than.

The trunk side wall of the layered hollow container of the present invention has an oxygen gas permeability and a gas permeability of carbon dioxide or gaseous, which are usually 1 Z 2 or less, preferably 1 Z 5 or less, as compared with those values of the thermoplastic resin layer. It is more preferably reduced to 1/10 or less. That is, the gas barrier uniform multilayer hollow container of the present invention includes, for example, polyolefin, polyester, polystyrene, polyvinyl chloride, polycarbonate, polylactic acid, polysuccinic ester, polyprolactone, polyamide, EVOH, polyurethane, P By combining a thermoplastic resin layer made of a resin selected from VDC etc. with a PGA layer as a gas barrier uniformity improving material, at least one of oxygen gas barrier property and carbon dioxide gas barrier property is compared with the thermoplastic resin layer As a result, a surprisingly improved hollow container can be obtained. Moreover, the multilayer hollow container of the present invention has a very small decrease in gas barrier properties even when subjected to a treatment under high temperature and high humidity.

The purpose of multi-layer hollow containers is to obtain the required properties that cannot be obtained with a single material by multi-layering. Specifically, it is necessary to provide gas barrier uniformity to oxygen, carbon dioxide, etc., to provide heat sealability, to improve moisture resistance, to improve mechanical strength, and to significantly reduce costs.

The method for producing the multilayer hollow container of the present invention can be broadly classified into a multilayer extrusion blow molding method and a multilayer injection blow molding method. These blow molding methods include a stretch blow molding method in which the film is stretched uniaxially or biaxially during professional molding, and a non-stretch blow molding method in which the film is not stretched. According to the stretch blow molding method, a multilayer stretch blow container can be obtained.

In multi-layer extrusion blow molding, first, a thermoplastic resin material containing polydalicholic acid The multi-layer parison is formed from a material, at least one thermoplastic resin, and optionally an adhesive. For this purpose, each resin material heated and melted by each extruder is allowed to flow into a multi-layer parison molding die (usually a circular die), where they are simultaneously or sequentially merged, and a tubular parison is pressed from the die. put out. Before the melt-extruded parison is solidified, it is sandwiched between split molds, one end of the parison is pinched, air is blown into the parison and blown to the mold wall, and cooled. After cooling, open the mold and remove the molded product. When the parison is stretched uniaxially or biaxially in the supercooled state or at a temperature lower than the crystallization temperature (T _C1 ) and slightly higher than the glass transition temperature T g during blowing, A molded product oriented in a uniaxial or biaxial direction can be obtained.

In injection pro-molding, a test tubular bottomed parison (preform) is injection-molded by injection molding, and the parison is blow-molded in a supercooled state or at a glass transition point Tg or more. After parison injection molding, the hot parison method is a method of controlling the temperature at a temperature below the melting point Tm without solidifying and then performing blow molding. On the other hand, after parison injection molding, the parison is once cooled and solidified, then reheated to a temperature of Tg or more, the temperature is adjusted, and the cold parison method is used.

The hot parison method includes stretch blow molding and unstretched pro-molding, whereas the cold parison method usually involves only stretch blow molding. In injection blow molding, a preform is formed by co-injection (coin injection) of a thermoplastic resin material containing polyglycolic acid, at least one thermoplastic resin and, if necessary, an adhesive. Blow molding by hot parison method or cold parison method. At this time, stretch blow molding or non-stretch blow molding is performed. The injection temperature is preferably in the range of the melting point Tm of polyglycolic acid to 255 ° C. If the injection temperature is too high, polydaricholic acid will be easily decomposed.

The multilayer hollow container of the present invention is used for, for example, a hollow container for beverages and foods, a container for toiletries, and a container for gasoline by utilizing its excellent oxygen gas barrier properties and / or carbon dioxide gas barrier properties. Especially in high temperature and high humidity such as retort sterilization It is preferably used for packaging containers such as articles requiring treatment, articles requiring special long-term storage, articles requiring carbon dioxide gas barrier properties, and articles requiring a reduction in environmental load. 8. Multilayer film

The multilayer film of the present invention comprises at least one thermoplastic resin film (hereinafter, sometimes referred to as “base film”) layer and a film layer made of a thermoplastic resin material containing polyglycolic acid (hereinafter, referred to as “ PGA layer). With the PGA layer, a multilayer film having excellent gas barrier properties can be obtained. If necessary, an adhesive layer can be interposed between the layers. The total thickness of the multilayer film is usually 2 ^ m to 3 mm, preferably 5 zm to 2 mm, more preferably 10 m to 1 mm. If the thickness is too small, it is difficult to manufacture and the cost is high, which is not preferable from the viewpoint of productivity and economy. If the thickness is too large, it is difficult to perform secondary processing for use as a packaging material, and the cost is high, which is not preferable from the viewpoint of productivity and economy.

The basic layer constitution of the multilayer film of the present invention is as follows. However, the adhesive layer is omitted. Further, a thermoplastic resin material containing polyglycolic acid is abbreviated as PGA.

(1) Thermoplastic resin ZPGA

(2) Thermoplastic resin 1 ZPGAZ thermoplastic resin 1

(3) Thermoplastic resin 1 ZPGA / thermoplastic resin 2

As long as the multilayer film of the present invention has the above-described basic layer configuration, it may be a laminate in which various kinds of thermoplastic resin films of the same type or different types are additionally laminated according to various required characteristics. . The method of compounding the thermoplastic resin film and the PGA layer is not particularly limited. For example, (1) a method in which each film is separately manufactured and then bonded, (2) another resin is extruded on one of the films. Various laminating methods such as coating method and ③ lamination method by co-extrusion method can be adopted. The thermoplastic resin film used in the present invention includes, for example, very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene. Polyolefins such as (HDPE), polypropylene (PP), ethylene propylene rubber (EPM), ethylene vinyl acetate copolymer (EVA), ethylene acrylate copolymer (EEA), and ionomer (1〇); polyethylene Polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polystyrene (PS), impact-resistant polystyrene (HI PS), styrene'butadiene-styrene-block copolymer (SBS), hydrogenated SB Polystyrene resins such as S (that is, SEBS); rigid polychlorinated vinyl, soft polychlorinated vinyl Polyvinyl chloride (PVC) resins such as Polyvinyl chloride (PC), Polyamide (PA), Polyurethane (PU), Ethylene vinyl alcohol copolymer (EVOH), Polyvinylidene chloride resin (PVDC) ) Is preferred.

As a thermoplastic resin film having a small environmental load, for example, a film formed from a biodegradable polymer such as polylactic acid, polysuccinate, and polyprolactone is preferable. These thermoplastic resins may be modified resins. Specifically, for example, LLDPE graft-modified with an acid such as acrylic acid can be mentioned.

In the multilayer film of the present invention, the thermoplastic resin film is used in a single layer or a multilayer. The thickness of the thermoplastic resin film is usually in the range of lzm to 2.5 mm, preferably 5 m to 2 mm, and more preferably 10 m to 1 mm. desirable.

In the present invention, an adhesive layer can be interposed between the thermoplastic resin film layer and the PGA layer in order to enhance the interlayer adhesion. The adhesive used for the adhesive layer includes, for example, polyoxylated polyolefin, epoxidized polyolefin, ethylene vinyl acetate copolymer, ionomer, polyurethane, epoxy resin, Examples include polymers such as SBS, SEBS, polychloroprene, styrene'butadiene copolymer rubber (SBR), and natural rubber (NR). The lipoxylated polyolefin is a polyolefin obtained by modifying a polyolefin with an unsaturated acid monomer such as acrylic acid, methacrylic acid or maleic anhydride to introduce a lipoxyl group. The introduction of the hydroxyl group may be carried out by either a copolymerization method or a grafting method. Further, the above unsaturated acid monomer may be used in combination with a vinyl monomer such as methacrylic acid ester, acrylic acid ester, and Bier acetate.

Epoxidized polyolefin is a polyolefin obtained by modifying a polyolefin with an epoxy group-containing monomer such as daricidyl mesylate and introducing an epoxy group. The epoxy group may be introduced by a copolymerization method or a grafting method. Further, the above-mentioned epoxy group-containing monomer may be used in combination with a vinyl-based monomer such as methacrylate, acrylate or vinyl acetate. Of these, olepoxylated polyolefin and ethylene / vinyl acetate copolymer are particularly preferred from the viewpoints of adhesion and workability. The thickness of the adhesive layer is usually in the range of 0.5 m to 2 mm, preferably 2 m to 1 mm, more preferably 3 ^ m to 0.5 mm. If the thickness is less than 0.5 zm, the adhesiveness may be insufficient, and application is difficult. If the thickness exceeds 2 mm, it is costly and disadvantageous from an economical point of view.

In the multilayer film of the present invention, in order to improve the oxygen gas barrier property and the Z or carbon dioxide gas barrier property of the thermoplastic resin film, a PGA layer is disposed as a gas barrier layer-I green resin layer. When a general thermoplastic resin film is used, both the oxygen gas barrier property and the carbon dioxide gas barrier property are improved.

When the multilayer film of the present invention is produced by a lamination method or an extrusion coating method, an oriented film of PGA can be used. The oriented film of PGA can be manufactured by melt-extruding the above-mentioned polydalicholate neat resin or a thermoplastic resin material containing the polyglycolic acid, stretching and orienting, and heat-fixing as necessary. . The melt film forming method includes uniaxial stretching by a flat die method, sequential biaxial stretching, and simultaneous biaxial stretching, or circuit For example, a method such as inflation biaxial stretching by the ィ method can be adopted.

By stretching in a multilayered state, a multilayer stretched film can be obtained. In addition, when multilayering is performed by coextrusion, a coextrusion multilayer stretched film can be obtained. The orientation state of the multilayer stretched film can be fixed by heat setting.

In the method for producing a multilayer film of the present invention, a multilayer film having a high heat shrinkage can be obtained by performing only stretching and omitting heat setting or adjusting the heat setting conditions. For example, a heat-shrinkable film having a heat-shrinkage ratio of more than 10% at 90 ° C can be obtained.

The thickness of the PGA layer, which is a barrier property improving material of the multilayer film of the present invention, is usually 0.5111 to 2111111, preferably 1 m to 1.5 mm. If the thickness is too small, the effect of improving the barrier uniformity may be insufficient. If the thickness is too large, the quality may be too high, which is economically disadvantageous. If necessary, a uniform thickness layer can be formed even if the PGA layer thickness is 5 βm or less, or even an extremely thin film thickness of about 1 to 3.

Specifically, when a set thickness of a layer mainly composed of polyglycolic acid at the time of forming a multilayer film is measured at 3 m, a variation (R%) from the set thickness is less than 200%. Can be obtained. The same applies when the set thickness is 1 im. The dispersion (R%) from the set thickness can be made less than 100% by making the melt viscosity of polydalicholic acid sufficiently small (for example, less than lOOPa-s). If the melt viscosity of polydalicholate is sufficiently low and the thickness of the layer mainly composed of polydalicholate at the time of molding is 5 m, the variation (R%) from the set thickness is 50%. It can also be less than.

The multilayer film of the present invention has an oxygen gas transmission rate and / or a carbon dioxide gas transmission rate of 1 to 2 or less, preferably 1Z5 or less, compared with those of a thermoplastic resin film (base film). More preferably, it can be improved to 110 or less. For example, polyolefin, polyester, polystyrene, polychlorinated vinyl, polycarbonate, polylactic acid, polysuccinate, polyprolactone, polyolefin By combining a film made of a thermoplastic resin such as lamide, EVOH, or PVDC with a PGA layer as a barrier property improving material, at least one of the oxygen gas transmission rate and the carbon dioxide gas transmission rate can be controlled by the thermoplastic resin. As a result, it is possible to obtain a multilayer film which is surprisingly improved as compared with a resin film. In addition, the multilayer film of the present invention has a very small decrease in gas barrier properties even when subjected to a treatment under high temperature and high humidity.

The method for producing the gas-barrier composite film of the present invention is roughly classified into the following methods.

① fusion method,

② Lamination method (dry lamination, hot melt lamination, ゥ et lamination, non-solvent lamination etc.) ',.

③ Extrusion coating method,

④Co-extrusion method (inflation method, T-die method, etc.).

In the fusing method, the surfaces of the thermoplastic resin film and the PGA film are aligned with each other, and using a hot roll, hot press, etc., the thermoplastic resin film in contact with the PGA film (for a multilayer film, The contact surface layer) can be composited by crimping at a temperature substantially above its melting point (Tm). At this time, it is desirable that the surface of the PGA film be mechanically roughened, activated by a corona treatment, activated by a chemical, or the like. In this fusion method, the bonding strength of the PGA film to a thermoplastic resin film having a small polarity such as a polyolefin film may be insufficient.

In the lamination method, the following method can be adopted.

(1) Dry lamination method:

Apply a solution-type, latex-type, or dispersion-type adhesive to the surface of the thermoplastic resin film or the surface of the PGA film, remove the solvent by volatilization, and dry it. A multilayer film is formed by press bonding while heating by a hot press or the like. (2) Hot melt lamination method:

Apply a hot-melt type adhesive (for example, EVA adhesive) to the surface of thermoplastic resin film or PGA film in the form of powder or film, and heat and press it together with the mating film surface to attach. Match. Hot-melt adhesive is heated and melted and applied to the surface of one of the films, then combined with the mating film and then bonded by pressing, or an adhesive film between the thermoplastic resin film and the PGA film Then, a multi-layer film can be obtained by a method of bonding by heating and pressing under pressure.

In the extrusion coating method, the resin constituting the thermoplastic resin film is supplied to an extruder equipped with a T-die, and is extruded from the T-die, while extruding the PGA film surface or the multilayer film surface including the PGA film layer. Then, a multilayer film can be obtained by uniformly applying in a molten film state. In this case, it is possible to apply an adhesive layer to the surface of the PGA film.

In the co-extrusion method, a resin to be a thermoplastic resin film such as polyolefin, polyester, polystyrene, polyvinyl chloride, etc .; a thermoplastic resin material containing a barrier property improving agent, polydaric acid; and, if necessary, both. The resin to be used as the adhesive is supplied from each extruder to one die, extruded simultaneously, and bonded in a molten state to produce a multilayer film in one step. The coextrusion method can be generally classified into a T-die method and an inflation method.

Typical examples of the T-die method include a laminar one-flow method using a single-manifold die, an in-die lamination method using a multi-manifold die, and an out-die lamination method using a dual slot die. The resin to be a thermoplastic resin film, the thermoplastic resin material containing polydalicholic acid, and the resin to be an adhesive, if necessary, are supplied from each extruder to one die, co-extruded, and cast. It is taken up in a roll, stretched to MD by a stretching roll, etc., stretched to TD by a tenter if necessary, and formed into a film, and heat-fixed as necessary to produce a multilayer film. In general, the T-die method is preferred for thin multilayer films with a thickness of 3 O ^ m or less. Good. ·

Representative examples of the inflation method include the in-die lamination method (such as the Roberto-Colombo method) and the out-die lamination method. Each extruder feeds a thermoplastic resin film, a thermoplastic resin material containing polyglycolic acid, and a resin to be an adhesive, if necessary, to one die, co-extrudes and inflates to form a tube. The film is formed into a film, and if necessary, pressed and pressed to form a flat film, and if necessary, heat-fixed to form a multilayer film.

The multilayer film of the present invention utilizes the excellent oxygen gas barrier properties and / or carbon dioxide gas barrier properties to form, for example, food packaging materials (meat, seafood, dairy products, pickles, miso, confectionery, tea). · Used for packaging materials such as coffee, men, rice, etc., toiletry packaging, and chemical packaging. In particular, it is preferably used as a packaging material for articles requiring treatment under high temperature and high humidity such as retort sterilization, articles requiring special long-term storage, and articles requiring a reduction in environmental load. Example

Hereinafter, the present invention will be described more specifically with reference to Synthesis Examples, Examples, and Comparative Examples. The methods for measuring physical properties are as follows.

(1) Melt viscosity 7 *:

As a sample, an amorphous sheet with a thickness of about 0.2 mm was prepared from polydalicholic acid in the molded product, and heated at about 150 ° C for 5 minutes to crystallize.D = 0.5 mm, L = The melt viscosity was measured using a 5 mm nozzle equipped capillary graph [manufactured by Toyo Seiki Co., Ltd.] at a polymer melting point Tm + 20 ° C and a shear rate of 100 / sec.

(2) Thermal properties of polymer:

As a sample, an amorphous sheet with a thickness of about 0.2 mm was prepared from polydalicholic acid in the molded product, and nitrogen gas was measured using a differential scanning calorimeter (DSC; TC-110A manufactured by Met's 1 er Co.). under a stream of air, at 10 / min heating at a Atsushi Nobori rate, crystallization temperature (T _{C l),} melting point (Tm), and to measure the melt Entarupi one (ΔΗπι). Glass-transition temperature (Tg) was measured at a heating rate of 5 ° CZ.

(3) Density of non-oriented crystallized product:

As a sample, an amorphous sheet with a thickness of about 0.2 mm was prepared from polydalicholic acid in the molded product, and heat-set at 150 ° C for 5 minutes, using JIS R-7222 (using n-butanol). Pycnometer method).

(4) Thickness:

For the thickness of the polyglycolic acid layer, etc., the average value was obtained by measuring the thickness of the sample at 10 locations using a micrometer (Mate, manufactured by SONY).

(5) Thickness variation (R%)

The thickness variation (R%) of the polyglycol J1 / acid layer was calculated as the variation from the set thickness, and evaluated according to the following criteria according to the type of each molded product.

① Oriented film

◎: R% is less than 10%,

〇: R% is 10% or more, less than 30%,

△: R% is 30% or more, less than 70%,

X: R% is 70% or more and / or PGA film breaks.

② Stretch blow container

◎: R% is less than 10%,

〇: R% is 10% or more, less than 30%,

A: R% is 30% or more, less than 70%,

X: R% is 70% or more.

③Multilayer hollow container

◎: R% is less than 50%,.

〇: R% is 50% or more, less than 100%,

△: R% is 100% or more, less than 200%,

X: R% is 200% or more, and Z or molding is impossible.

④Multilayer film ◎: 1% less than 50%,

〇: R% is 50% or more, less than 100%,

△: R% is 100% or more, less than 200%,

X: R% is 200% or more.

(6) Soil disintegration

The test piece is buried in the soil of the field at a depth of about 10 cm, excavated after 6 months, washed, dried and weighed, and the weight ratio (% by weight) to the initial weight of the test piece is determined. Calculated.

[Synthesis Example 1] Synthesis of glycolide

5 kg of glycolic acid (manufactured by Wako Pure Chemical Industries, Ltd.) is charged into a 10-liter autoclave, and the temperature is raised from 110 ° C to 200 ° C for about 2 hours while stirring, and the generated water is distilled. While condensing. Then, the pressure was reduced to 20 kPa (20 Ombar), and the mixture was kept for 2 hours to distill off the low boiling components, thereby preparing a glycolic acid oligomer. The melting point Tm of the glycolic acid oligomer was 205.

Glycolic acid oligomer 1.2 kg is charged into a 10-liter flask, and benzyl butyl phosphate 5 kg (produced by Junsei Chemical Co., Ltd.) as a solvent and polypropylene glycol (produced by Junsei Chemical Co., Ltd., # 400 150 g, and heated to about 270 ° C under a reduced pressure of 5 kPa (5 Ombar) in a nitrogen gas atmosphere to perform `` solution phase depolymerization '' of the glycolic acid oligomer, and convert the formed glycolide to benzyl butyl phthalate. Co-distilled. Approximately twice the volume of cyclohexane was added to the obtained co-distillate to precipitate dalicollide from benzyl butyl phthalate, which was separated by filtration. This was recrystallized using ethyl acetate and dried under reduced pressure to obtain purified glycolide.

[Synthesis Example 2] Synthesis of polyglycolic acid (PGA-a)

100 g of glycolide, 6 mg of tin octoate, and 5 Omg of lauryl alcohol were charged into a glass test tube, and polymerized at 220 T for 3 hours. After the polymerization, the resulting polymer was taken out after cooling, pulverized, and washed with acetone. Thereafter, the polymer was vacuum-dried at 30 ° C. to recover the polymer. Repeat the same operation until the required amount of polyg Licholic acid was synthesized.

[Synthesis example · 3] Synthesis of polyglycolic acid (PGA-b)

Glycolide with 300 ppm of tetrachloride at a rotational speed of 15 rpm and a temperature setting of 200-240 ° C (with a resin temperature of 240) using a LT-20 made by Toyo Seiki Co., Ltd. with a 5 mm hole die. Tin pentahydrate was added and charged from a hopper to carry out polymerization.

[Synthesis Example 4] Synthesis of polyglycolic acid (PGA-c)

100 g of glycolide and 4 mg of tin dichloride dihydrate were polymerized in a glass test tube at 180 for 2 hours. At the end of the reaction, the polymer had solidified. After cooling, the polymer was taken out, pulverized, washed with acetone, and vacuum-dried at 30 ° C to obtain a polymer. The same operation was repeated to synthesize the required amount of polyglycolic acid.

[Example 1] Compression molded product

The polyglycolic acid (PGA-a) obtained in Synthesis Example 2 was supplied under a nitrogen gas flow to a small twin-screw kneader equipped with a 3 mm φ nozzle, and was in a strand state at a melting temperature of about 230 to 240 ° C. And air-cooled and cut to obtain pellets. The pellets were supplied to a molding machine to form a sheet at a resin temperature of about 235 ° C. The sheet was compression-molded at a pressure of 40 kgf / cm ² and a temperature of Ι ΟΤ ΟΤλ for 5 seconds to obtain a tray (depth 30 mm, bottom 100 mm × 200 mm, thickness 500 Atm).

Properties of Poridarikoru acid of the molded product in the melt viscosity of 5 OP a · s, the crystallization temperature (T _{C l)} is 84 ° (:, melting point (Tm) is 222 ° C, melt Entarupi (.DELTA..eta m) is 74 JZg, glass transition temperature (Tg) was 38, and the density of the non-oriented crystallized product was 1.58 g / cm ^3. 'Using this molded product as a test piece, a soil breaking test was performed. The results are shown in Table 1.

[Example 2] Compression molded product

A tray was prepared in the same manner as in Example 1 except that the polyglycolic acid (PGA-b) obtained in Synthesis Example 3 was used instead of the polyglycolic acid (PGA-a).

The physical properties of polydalicholic acid in this molded product were as follows: melt viscosity 300 Pa · s, crystallization temperature (Tc) 85 ° C, melting point (Tm) 222 ° C, melt enthalpy (ΔΗ m) was 75 J / g, the glass transition temperature (Tg) was 38 ° C, and the density of the non-oriented crystallized product was 1.58 gZcm ³ . Using this molded product as a test piece, a soil collapse test was performed. Table 1 shows the results.

[Comparative Example 1] Compression molded product

A tray was produced in the same manner as in Example 1 except that the polyglycolic acid (PGA-c) obtained in Synthesis Example 4 was used instead of the polyglycolic acid (PGA-a). '' The physical properties of polydalicholate in this molded product are as follows: melt viscosity is 800 Pa · s, crystallization temperature (Tc ^) is 86 ° C, melting point (Tm) is 222 ° C, and melt enthalpy (ΔΗm) is The glass transition temperature (Tg) was 38 JZg, and the density of the non-oriented crystallized product was 1.58 gZ cm ³ . Using this molded product as a test piece, a soil collapse test was performed. Table 1 shows the results.

[Comparative Example 2] Compression molded product

A tray was prepared in the same manner as in Example 1, except that polyethylene glycol terephthalate (PET; manufactured by Mitsui Pet Co., Ltd., J135) was used instead of polyglycolic acid (PGA-a). A medium disintegration test was performed. Table 1 shows the results.

table 1

As is clear from the results in Table 1, when the melt viscosity of polyglycolic acid is as low as less than 500 Pa · s (Examples 1 and 2), collapse in soil proceeds very quickly, and composting occurs in a short period of time. It can be seen that conversion is possible.

[Example 3] Orientation: To 100 parts by weight of the polyglycolic acid (PGA-a) obtained in Synthesis Example 2, 0.1 part by weight of alumina powder was added and supplied to a small twin-screw extruder equipped with a 3ππηφ nozzle under nitrogen gas flow Then, it was extruded into a strand at a melting temperature of about 230 to about 235, quenched, and cut to form a pellet.

This pellet was supplied to a small twin-screw extruder equipped with a ring die for inflation under a nitrogen gas stream, and extruded from the ring die into a tube at a resin temperature of about 230 ° C. Next, the tube was quenched by a cooling bath to a temperature of Tg or less, and blown at 40 to 45 ° C with a blow ratio of about 3 times. The take-up speed was controlled so that the stretching ratio in the longitudinal direction of the tube was about three times, and the film was wound up through a nip roll to prepare a tube-like film. This film was heat-set at 150 ° C. for 1 minute to obtain a biaxially oriented film (drawing ratio: 3 × 3, thickness: 15 im). Furthermore, a biaxially oriented film having a thickness of 25 m and 40 im was produced by adjusting the blow ratio and the stretching ratio in the longitudinal direction.

The melt viscosity of polydalicholate in these biaxially oriented films was 55 Pa · s. The variation R% from the set thickness of each biaxially oriented film was measured. Table 2 shows the measurement results.

[Example 4] Orientation:

In the same manner as in Example 3 except that the polyglycolic acid (PGA-b) obtained in Synthesis Example 3 was used instead of the polyglycolic acid (PGA-a), the thickness was 15 m, 25 m and A biaxially oriented film of 40 im was produced. The melt viscosity of polyglycolic acid in these biaxially oriented films was 31 OPa · s. The variation R% from the set thickness of each biaxially oriented film was measured. Table 2 shows the measurement results.

[Comparative Example 3] Orientation:

In the same manner as in Example 3 except that the polyglycolic acid (PGA-c) obtained in Synthesis Example 4 was used instead of the polyglycolic acid (PGA-a), the thickness was 15 ^ 111, 2 m And a 40 m biaxially oriented film was prepared. The melt viscosity of polydaricholic acid in these biaxially oriented films was 820 Pa · s. Each biaxially oriented film The variation R% from the set thickness was measured. Table 2 shows the measurement results.

Table 2

As is clear from the results in Table 2, when the melt viscosity of polydalicholic acid is as low as less than 50 OPa · s (Examples 3 and 4), the viscosity is as low as 40 m or less, and even as low as 15 to 25 im. However, it is possible to obtain an oriented film having small variation from the set thickness.

[Example 5] Stretch blow container

The polyglycolic acid (PGA-a) obtained in Synthesis Example 2 was supplied to a small twin-screw kneading extruder equipped with a 3 mm Φ nozzle under a nitrogen gas flow, and was made into strands at a melting temperature of about 230 to 240. It was melt-extruded, air-cooled and cut to obtain pellets. The pellets are supplied to an injection molding machine, injected (injected) into a bottomed parison mold (temperature of about 10 ° C) at a resin temperature of about 230 ° C, solidified, taken out, and formed into a cold parison preform. (Thickness: about 1.6 mm, outer diameter: about 1.6 cm, length: about 5 cm, spherical shape at bottom). The obtained cold preform is preheated to about 42 ° C to soften it, and a stretching rod is inserted to stretch it about 225 times in the machine direction, and at the same time, the body outer diameter is about 4.5 cm, the body is Approximately 9 cm in length, approximately 1.6 cm in neck outer diameter, approximately 1 cm in neck length, sandwiched by two halves of a flat-bottom central concave bottle, blown with high-pressure gas at a blow ratio of approximately 2.8, The bottle was stretched and oriented in the circumferential direction (horizontal direction) to form a bottle, and the bottle was heat-set at 150 ° C for 10 seconds by blowing high-pressure gas, then removed from the mold to form a stretch blow container. . The obtained stretch blow container was transparent. By adjusting the blow ratio and the stretching ratio in the machine direction, each stretch blow container having a body thickness of 50 τ, 100 m, and 200; m was prepared. The melt viscosity of polydalicholate in these stretch blow containers was 45 Pa · s. Further, the variation R% from the set thickness of the body of these stretch blow containers was measured. Table 3 shows the results.

[Example 6] Stretch blow container

In the same manner as in Example 5 except that the polyglycolic acid (PGA-b) obtained in Synthesis Example 3 was used instead of the polyglycolic acid (PGA-a), the body thickness was 50 m, and m, and a stretch blow container of 200 m were produced. The melt viscosity of polydalicholic acid in one of these stretching processors was 290 Pa's. In addition, the variation R% from the set thickness of the body portion of each of the stretching mouths was measured. Table 3 shows the results.

[Comparative Example 4] Stretch blow container

In the same manner as in Example 5 except that the polyglycolic acid (PGA-c) obtained in Synthesis Example 4 was used instead of the polyglycolic acid (PGA-a), the body thickness was 50 m, and rn, and 200 m of each stretch blow container were prepared. The melt viscosity of the polyglycolic acid in these stretch blow containers was 780 Pa * s. Further, the variation R% from the set thickness of the body of these stretch blow containers was measured. Table 3 shows the results.

Table 3

Polyglycolic acid stretch blow container (thickness variation)

Web thickness Thickness setting Thickness code Melt viscosity (Pa * s)

50 ITL lOO ^ m 200 m Example 5 PGA-a 45 ◎ ◎ ◎ Example 6 PGA-b 290 Δ 〇 ◎ Comparative Example 4 PGA- c 780 X △ 〇 As is evident from the results in Table 3, when the melt viscosity of polyglycolic acid was as low as less than 500 Pa · s (Examples 5 to 6), the thickness of the body was 200 or less, and more preferably 50 to 50%. : Even if it is as thin as L00; m, it is possible to obtain a stretch blow container having a small variation from the set thickness.

[Example 7] Multi-layer hollow container

The polyglycolic acid (0PGA-a) obtained in Synthesis Example 2 was supplied to a small twin-screw kneading extruder equipped with a 3 mm Φ nozzle under nitrogen gas flow, and was formed into a strand at a melting temperature of about 230 to 240 ° C. It was melt-extruded, air-cooled and cut to obtain pellets. The pellets, polyethylene terephthalate (PET; J 135, manufactured by Mitsui Pet Co., Ltd.), and lipoxylated polyolefin (registered trademark MOD IC E-300S) were supplied to a three-type, five-layer co-injection molding machine and injected. Then, it was poured into a preform mold to form a preform (outer diameter of about 2 cm, length of about 6 cm), and was cooled and solidified. Next, the preform is reheated, adjusted to a temperature of about 85 ° C., inserted into a mold, and a mouth is inserted into the preform. At the same time as the double stretching, it was blown at a blow ratio of about 3 and then cooled and solidified to produce a multilayer hollow container having a layer structure of PET / PGA / PET.

By adjusting the stretching ratio and the blow ratio, each multilayer hollow container having a core layer having a PGA layer thickness of 3 m, 5 μ, πι, and 10 jm was produced. The melt viscosity of the polyglycolic acid in the PGA layer of these multilayer containers was 50 Pa * s. The variation R% from the set thickness of the body core layer of these multilayer hollow containers was measured. Table 4 shows the results.

[Example 8] Multi-layer hollow container

In the same manner as in Example 7 except that the polyglycolic acid (PGA-b) obtained in Synthesis Example 3 was used instead of the polyglycolic acid (PGA-a), the thickness of the core layer PGA layer was changed. Multilayer hollow containers of 3 mm, 5 urn, and 10 im were prepared. The melt viscosity of the polyglycolic acid in the PGA layers of these multilayer containers was 300 Pa * s. The variation R% from the set thickness of the body core layer of these multilayer hollow containers was measured. Table 4 shows the results. [Comparative Example 5] Multi-layer hollow container

In the same manner as in Example 7, except that the polyglycolic acid (PGA-c) obtained in Synthesis Example 4 was used instead of the polyglycolic acid (PGA-a), the thickness of the core layer PGA layer was changed. Produced 3 m, 5 urn, and 10 ^ m multilayer hollow containers. The melt viscosity of polydalicholate in the PGA layer of these multilayer containers was 800 Pa's. The variation R% from the set thickness of the body core layer of these multilayer hollow containers was measured. Table 4 shows the results.

Table 4

As is clear from the results in Table 4, when the melt viscosity of the polyglycolic acid was as low as less than 500 Pa · s (Examples? To 8), the thickness of the body core layer was 10 m or less, and It is possible to obtain a multilayer hollow container with a small variation from the set thickness even when the thickness is extremely thin, such as 3 to 5 zm.

[Example 9] Multi-layer '

The polyglycolic acid (PGA-a) obtained in Synthesis Example 2 was supplied under a nitrogen gas flow to a small twin-screw kneading extruder equipped with a 3 mm φ nozzle, and was stranded at a melting temperature of 230 to 240 ° C Then, the mixture was melt-extruded, air-cooled and cut to obtain pellets.

These pellets and acid-modified LLDPE (Admer NF 550; Mitsui Chemicals, Inc., acid graph LLDPE) are extruded from each extruder at a resin temperature of about 230 ° C, and are formed into three layers by a feed block (acid-modified LLDPE). / PGA / acid-modified LLDP E) Yes. The die is 30 cm wide, and the acid modified LLDPE of the inner layer is 35mm <i) extruder, the acid modified LLDPE of the outer layer is 40πιπιφ extruder, and the PGA of the core layer is 25πιπιφ extruder And extruded to form a film.

By adjusting the extrusion amount of the core layer, multilayer films having a core layer thickness of 1 m, 3 3τι, and 5 m, respectively, were produced. The melt viscosity of the polyglycolic acid in the PGA layer of these multilayer films was 55 Pa's. The variation R% from the set thickness of the core layer of these multilayer films was measured. Table 5 shows the results.

[Example 10] Multilayer film

In the same manner as in Example 9 except that the polyglycolic acid (PGA-b) obtained in Synthesis Example 3 was used instead of the polyglycolic acid (PGA-a), the thickness of the core layer was 1 urn. , 3 urn, and 5 were prepared. The melt viscosity of polydalicholate in the PGA layer of these multilayer films was 31 OPas. The variation R% from the set thickness of the core layer of these multilayer films was measured. Table 5 shows the results. '' [Comparative Example 6] Multilayer film

In the same manner as in Example 9, except that the polyglycolic acid (PGA-c) obtained in Synthesis Example 4 was used instead of the polyglycolic acid (PGA-a), Multilayer films of 1 urn, 3 m, and 5 m were prepared. The melt viscosity of polydalicholate in the PGA layer of these multilayer films was 82 OPa's. The variation R% from the set thickness of the core layer of these multilayer films was measured. Table 5 shows the results. Table 5

As is evident from the results in Table 5, when the melt viscosity of polydaricholic acid is as low as less than 50 OPa · s (Examples 9 to 10), the thickness of the core layer is 5 m or less, and more preferably 1 to 10 Even when the thickness is as thin as 3 m, a multilayer film with a small variation from the set thickness can be obtained. Industrial applicability

ADVANTAGE OF THE INVENTION According to the present invention, a thermoplastic resin material containing polydaricholic acid that has excellent fluidity in a molten state, enables uniform film formation, has remarkable biodegradability, and enables rapid composting Various single-layer or multi-layer molded articles such as compression molded articles, extruded molded articles, oriented films, drawn professional containers, multilayer hollow containers, multilayer films, and fibers are provided.

Claims

The scope of the claims

1. The following equation (1)

A polyglycolic acid molded product containing as a main component a polyglycolic acid containing at least 60% by weight of a repeating unit represented by the formula:

(a) the melt viscosity of polydalicholic acid in the molded product is 20 Pa's or more and less than 500 Pa's when measured at a temperature 20 ° C. higher than the melting point and a shear rate of 100 / sec, and

(b) Molded by molding methods including compression molding, extrusion molding, blow molding, or solution casting

A molded article of polydalicholic acid, characterized in that:

2. In the soil decay test, the ratio of weight (X) to initial weight (y) after burying in soil for 6 months [(x / y) X 100 (%;)] is 50% or less. The molded article of polydalicholic acid according to claim 1, which exhibits disintegration property in soil.

3. The molded article of polyglycolic acid according to claim 1, wherein the molded article formed by compression molding is a tray.

4. The polyglycolic acid molded product according to claim 1, wherein the molded product formed by extrusion is a sheet, an unstretched film, a stretched film, a stretched oriented film, a fiber, or a secondary molded product thereof.

5. The following equation (1)

Is an oriented film mainly composed of polydaricholic acid containing 60% by weight or more of a repeating unit represented by the formula: wherein the melt viscosity of polydalicholic acid in the oriented film is 20 ° C. higher than the melting point and the shear rate is 100. Oriented film that is not less than 20 Pa · s and less than 500 Pa · s when measured under the condition of / sec.

6. The oriented film according to claim 5, wherein a variation (R%) from the set thickness is less than 30% when the set thickness at the time of molding is measured as 25 m.

7. The following formula (1)

0-CH.-C

2 II (1)

A stretch-blow container mainly composed of polyglycolic acid containing at least 60% by weight of a repeating unit represented by o, wherein the melt viscosity of polydalicholic acid in the stretch-blow container is 20 ° C higher than the melting point and a shearing temperature. A stretch blow container having a speed of 20 Pa · s or more and less than 500 Pa's when measured at a speed of 100 / sec.

8. The stretch blow container according to claim 7, wherein a variation (R%) from the set thickness is less than 30% when the set body thickness at the time of molding is measured as 100 zm.

9. The following formula (1)

0-CH ₂ -C

Polyglycolic acid containing 60% by weight or more of the repeating unit represented by (1) as the main component A multilayer molded article having a layer structure in which a thermoplastic resin layer is formed on at least one surface of a layer to be formed, wherein the melt viscosity of polydalicholate in the layer containing polydalicholate as a main component is higher than the melting point by 20. When measured under conditions of temperature and shear rate 100Z seconds,

Multi-layer molded product of 20 Pa · s or more and less than 500 Pa · s.

10. The multilayer molded article according to claim 9, which is a multilayer sheet. The following formula (1)

A multilayer hollow container having a layer structure in which a thermoplastic resin layer is formed on at least one surface of a layer containing polyglycolic acid as a main component containing a repeating unit represented by the formula: A multilayer hollow container having a melt viscosity of polydalicholate in a layer mainly composed of 20 Pa's or more and less than 500 Pa * s when measured at a temperature 20 ° C higher than the melting point and a shear rate of 100 Z seconds. 12. The multilayer hollow container according to claim 11, which is a multilayer stretch blow container.

13. The multilayer hollow container according to claim 11, wherein the multilayer hollow container has a layer configuration in which a thermoplastic resin layer is formed on both sides of a layer containing polydalicholate as a main component. 14. The multilayer hollow container according to claim 11, wherein a variation (R%) from the set thickness is less than 200% when the set thickness of the layer mainly containing polydalicholate during molding is measured as 5 m.

15. The following equation (1)

A multilayer film having a layer structure in which a thermoplastic resin layer is formed on at least one surface of a layer mainly composed of polydalicholic acid containing a repeating unit represented by the following formula in an amount of 60% by weight or more. A multilayer film having a melt viscosity of polydaricholic acid in a layer of not less than 20 Pa · s and less than 500 Pa · s when measured at a temperature 20 ° C. higher than the melting point and a shear rate of 100 / sec.

16. The multilayer film according to claim 15, wherein the multilayer film has a layer configuration in which a thermoplastic resin layer is formed on both surfaces of a layer containing polydalicholate as a main component. 17. The multilayer film according to claim 15, wherein a variation (R%) from the set thickness is less than 200% when the set thickness of the layer mainly containing polyglycolic acid at the time of molding is measured as 3.

8. The multilayer film according to claim 17, which is a multilayer stretched film.

9. The multilayer film according to claim 18, which is a multilayer stretched film obtained by co-extrusion.

20. The multilayer film according to claim 18, which is a heat-shrinkable film.