JP2021161381A - Biaxially stretched film, multilayer film, packaging bag, and manufacturing method of biaxially stretched film - Google Patents

Biaxially stretched film, multilayer film, packaging bag, and manufacturing method of biaxially stretched film Download PDF

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JP2021161381A
JP2021161381A JP2021005784A JP2021005784A JP2021161381A JP 2021161381 A JP2021161381 A JP 2021161381A JP 2021005784 A JP2021005784 A JP 2021005784A JP 2021005784 A JP2021005784 A JP 2021005784A JP 2021161381 A JP2021161381 A JP 2021161381A
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stretched film
biaxially stretched
propylene
based polymer
mass
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直 井上
Tadashi Inoue
将 金坂
Susumu Kanesaka
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Sumitomo Chemical Co Ltd
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Abstract

To provide a biaxially stretched film of polypropylene system having small heat shrinkage and a manufacturing method of the biaxially stretched film capable of manufacturing the biaxially stretched film.SOLUTION: The biaxially stretched film of the present invention contains a propylene system polymer or a propylene system polymer composition satisfying requirements (1) and (2), and satisfies requirements (3) and (4). (1) MFR is 1 to 50 g/10 minutes. (2) CXS is 2.0 mass% or smaller. (3) A half value width of the maximum peak when the scattering intensities of 040 plane of an α type crystal of the biaxially stretched film cross-section orthogonal to the MD direction, measured by using a wide angle X-ray scattering method, are plotted against the azimuthal angle is 13.0° or smaller, (4) A formula 0.42×E×(1-X)≤600 (I) is satisfied. (In formula (I), E shows the complex elastic modulus (MPa) in the TD direction of the biaxially stretched film, and X is X=14.18-12.34/D (II) (in the formula (II), D shows density (g/cm3) of the biaxially stretched film)).SELECTED DRAWING: None

Description

本発明は、二軸延伸フィルムに関するものである。より詳しくは、プロピレン系重合体又はプロピレン系重合体組成物を含有する二軸延伸フィルムと該二軸延伸フィルムを備えた多層フィルム、包装体、および二軸延伸フィルムの製造方法に関するものである。 The present invention relates to a biaxially stretched film. More specifically, the present invention relates to a biaxially stretched film containing a propylene-based polymer or a propylene-based polymer composition, a multilayer film including the biaxially stretched film, a package, and a method for producing the biaxially stretched film.

従来、例えば各種包装材料として用いられるフィルムとしては、ポリエチレンテレフタレート(PET)系二軸延伸フィルムを基材フィルムとし、該基材フィルムに、ポリプロピレン(PP)系無延伸フィルムやポリエチレン(PE)系無延伸フィルムをシーラントフィルムとして積層した構成のものが知られている。かかる構成のフィルムは、基材フィルムが高剛性および高耐熱性を有し、シーラントフィルムが低温でのヒートシール性を有していることで、各種包装袋として優れた機能を発揮しうるものとなっている。 Conventionally, for example, as a film used as various packaging materials, a polyethylene terephthalate (PET) -based biaxially stretched film is used as a base film, and the base film is a polypropylene (PP) -based non-stretched film or a polyethylene (PE) -based non-stretched film. A structure in which a stretched film is laminated as a sealant film is known. The film having such a structure can exhibit excellent functions as various packaging bags because the base film has high rigidity and high heat resistance and the sealant film has heat sealing property at low temperature. It has become.

近年、この種のフィルムに対してもリサイクルの要望が高まっており、モノマテリアル化が求められている。具体的には、ポリプロピレンやポリエチレンといったオレフィン系樹脂で構成されるシーラントフィルムと同種のオレフィン系樹脂であるポリプロピレン系二軸延伸フィルムを基材フィルムとして採用することが好適とされる。 In recent years, there has been an increasing demand for recycling of this type of film, and there is a demand for monomaterialization. Specifically, it is preferable to use a polypropylene-based biaxially stretched film, which is an olefin-based resin of the same type as a sealant film composed of an olefin-based resin such as polypropylene or polyethylene, as a base film.

しかしながら、ポリプロピレン系二軸延伸フィルムはポリエチレンテレフタレート系二軸延伸フィルム等と比較して加熱収縮率が大きく、ポリプロピレン系二軸延伸フィルムを基材フィルムとして用いたフィルムは、その用途が制限されるという問題があった。 However, the polypropylene-based biaxially stretched film has a larger heat shrinkage rate than the polyethylene terephthalate-based biaxially stretched film and the like, and the use of the film using the polypropylene-based biaxially stretched film as the base film is limited. There was a problem.

耐熱性を改善したポリプロピレン系二軸延伸フィルムとしては、従来、下記特許文献1記載のフィルムが知られている。具体的には、該特許文献1には、高立体規則性のポリプロピレンを、所定の範囲の結晶配向を有する延伸ポリプロピレンフィルムとすることで、熱収縮性および剛性を改善する方法が開示されている。 As a polypropylene-based biaxially stretched film having improved heat resistance, the film described in Patent Document 1 below is conventionally known. Specifically, Patent Document 1 discloses a method of improving heat shrinkage and rigidity by using polypropylene having high stereoregularity as a stretched polypropylene film having a crystal orientation in a predetermined range. ..

しかし、特許文献1記載のフィルムでは、高温での収縮率は十分なものとはいえず、さらなる加熱収縮率の改良にはオフラインでのアニール処理を必要とするなど、二軸延伸フィルムの製造についての制約が多いものであった。 However, the film described in Patent Document 1 does not have a sufficient shrinkage rate at high temperatures, and an offline annealing treatment is required to further improve the heat shrinkage rate. There were many restrictions.

国際公開第2015/012324号International Publication No. 2015/012324

本発明は、二軸延伸フィルムの製造について上記のような制約を受けることなく、加熱収縮率の小さいポリプロピレン系の二軸延伸フィルムを提供すること、および該二軸延伸フィルムを備えた多層フィルム、包装体、並びに該二軸延伸フィルムを製造しうる二軸延伸フィルムの製造方法、を提供することを課題とする。 The present invention provides a polypropylene-based biaxially stretched film having a small heat shrinkage rate without being restricted by the above-mentioned restrictions on the production of the biaxially stretched film, and a multilayer film provided with the biaxially stretched film. An object of the present invention is to provide a package and a method for producing a biaxially stretched film capable of producing the biaxially stretched film.

本発明の二軸延伸フィルムは、下記要件(1)および下記要件(2)を満たすプロピレン系重合体またはプロピレン系重合体組成物を含有し、
下記要件(3)および下記要件(4)を満たすものである。
(1)温度230℃、荷重21.18Nで測定されるメルトフローレートが1g/10分〜50g/10分である。
(2)冷キシレン可溶部量が2.0質量%以下である。
(3)広角X線散乱法を用いて、二軸延伸フィルムのMD方向と直交する二軸延伸フィルムの断面にX線を入射して測定されるプロピレン系重合体のα型結晶の040面の散乱強度を、方位角に対してプロットした時の最大ピークの半値幅が13.0°以下である。
(4)下記式(I)を満たす。
0.42×E×(1−X)≦600 (I)
(式中、
Eは、温度70℃で測定される二軸延伸フィルムのTD方向の複素弾性率(MPa)を示す。
Xは、下記式(II)で算出される値を示す。)
X=14.18−12.34/D (II)
(式中、Dは、二軸延伸フィルムの密度(g/cm)を示す。)
The biaxially stretched film of the present invention contains a propylene-based polymer or a propylene-based polymer composition that satisfies the following requirements (1) and the following requirements (2).
It meets the following requirements (3) and the following requirements (4).
(1) The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 1 g / 10 minutes to 50 g / 10 minutes.
(2) The amount of the soluble part of cold xylene is 2.0% by mass or less.
(3) Using the wide-angle X-ray scattering method, the 040 plane of the α-type crystal of the propylene-based polymer measured by injecting X-rays into the cross section of the biaxially stretched film orthogonal to the MD direction of the biaxially stretched film. The half-value width of the maximum peak when the scattering intensity is plotted against the azimuth angle is 13.0 ° or less.
(4) The following formula (I) is satisfied.
0.42 x E x (1-X) ≤ 600 (I)
(During the ceremony,
E indicates the complex elastic modulus (MPa) in the TD direction of the biaxially stretched film measured at a temperature of 70 ° C.
X represents a value calculated by the following formula (II). )
X = 14.18-12.34 / D (II)
(In the formula, D indicates the density (g / cm 3 ) of the biaxially stretched film.)

また、本発明の二軸延伸フィルムの製造方法は、下記要件(1)および下記要件(2)を満たすプロピレン系重合体またはプロピレン系重合体組成物を、押出機を用いて加熱溶融し、冷却ロール上に押し出すことにより未延伸シートを得る工程と、
得られた未延伸シートを、MD方向に3倍〜12倍に延伸し且つTD方向に4倍〜20倍に延伸した後、該TD方向に16%〜30%緩和することにより二軸延伸フィルムを得る工程と、を含むものである。
(1)温度230℃、荷重21.18Nで測定されるメルトフローレートが1g/10分〜50g/10分である。
(2)冷キシレン可溶部量が2.0質量%以下である。
Further, in the method for producing a biaxially stretched film of the present invention, a propylene-based polymer or a propylene-based polymer composition satisfying the following requirements (1) and the following requirements (2) is heated and melted using an extruder and cooled. The process of obtaining an unstretched sheet by extruding onto a roll,
The obtained unstretched sheet is stretched 3 to 12 times in the MD direction and 4 to 20 times in the TD direction, and then relaxed by 16% to 30% in the TD direction to form a biaxially stretched film. The process of obtaining the above is included.
(1) The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 1 g / 10 minutes to 50 g / 10 minutes.
(2) The amount of the soluble part of cold xylene is 2.0% by mass or less.

本発明によれば、加熱収縮率の小さいポリプロピレン系の二軸延伸フィルムを提供することができる。また、本発明によれば、該二軸延伸フィルムを製造しうる二軸延伸フィルムの製造方法、を提供することができる。 According to the present invention, it is possible to provide a polypropylene-based biaxially stretched film having a small heat shrinkage rate. Further, according to the present invention, it is possible to provide a method for producing a biaxially stretched film capable of producing the biaxially stretched film.

本発明で用いられるプロピレン系重合体は、プロピレン単独重合体またはプロピレン系ランダム共重合体である。得られる二軸延伸フィルムの加熱収縮率および剛性の観点から、好ましくはプロピレン単独重合体である。本発明で用いられるプロピレン系重合体がプロピレン系ランダム共重合体の場合、プロピレンと、エチレンおよび炭素原子数4〜20のα−オレフィンから選択された少なくとも1種のコモノマーと、を共重合して得られるプロピレン系ランダム共重合体が挙げられる。 The propylene-based polymer used in the present invention is a propylene homopolymer or a propylene-based random copolymer. From the viewpoint of heat shrinkage and rigidity of the obtained biaxially stretched film, a propylene homopolymer is preferable. When the propylene-based polymer used in the present invention is a propylene-based random copolymer, propylene is copolymerized with ethylene and at least one comonomer selected from α-olefin having 4 to 20 carbon atoms. Examples thereof include the obtained propylene-based random copolymer.

炭素原子数4〜20のα−オレフィンとしては、例えば、1−ブテン、2−メチル−1−プロペン、1−ペンテン、2−メチル−1−ブテン、3−メチル−1−ブテン、1−ヘキセン、2−エチル−1−ブテン、2,3−ジメチル−1−ブテン、2−メチル−1−ペンテン、3−メチル−1−ペンテン、4−メチル−1−ペンテン、3,3−ジメチル−1−ブテン、1−ヘプテン、メチル−1−ヘキセン、ジメチル−1−ペンテン、エチル−1−ペンテン、トリメチル−1−ブテン、メチルエチル−1−ブテン、1−オクテン、メチル−1−ペンテン、エチル−1−ヘキセン、ジメチル−1−ヘキセン、プロピル−1−ヘプテン、メチルエチル−1−ヘプテン、トリメチル−1−ペンテン、プロピル−1−ペンテン、ジエチル−1−ブテン、1−ノネン、1−デセン、1−ウンデセン、1−ドデセン等が挙げられる。前記α−オレフィンは、好ましくは、1−ブテン、1−ペンテン、1−ヘキセン、または1−オクテンであり、より好ましくは1−ブテンである。 Examples of α-olefins having 4 to 20 carbon atoms include 1-butene, 2-methyl-1-propene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, and 1-hexene. , 2-Ethyl-1-butene, 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl-1 -Butene, 1-hexene, methyl-1-hexene, dimethyl-1-pentene, ethyl-1-pentene, trimethyl-1-butene, methylethyl-1-butene, 1-octene, methyl-1-pentene, ethyl- 1-Hexene, dimethyl-1-hexene, propyl-1-heptene, methylethyl-1-heptene, trimethyl-1-pentene, propyl-1-pentene, diethyl-1-butene, 1-nonene, 1-decene, 1 -Undesen, 1-dodecen, etc. can be mentioned. The α-olefin is preferably 1-butene, 1-pentene, 1-hexene, or 1-octene, and more preferably 1-butene.

本発明でプロピレン系重合体として用いられるプロピレン系ランダム共重合体としては、例えば、プロピレン−エチレンランダム共重合体、プロピレン−α−オレフィンランダム共重合体等が挙げられる。プロピレン−α−オレフィンランダム共重合体としては、例えば、プロピレン−1−ブテンランダム共重合体、プロピレン−1−ヘキセンランダム共重合体、プロピレン−1−オクテンランダム共重合体、プロピレン−エチレン−1−ブテンランダム共重合体、プロピレン−エチレン−1−ヘキセンランダム共重合体、プロピレン−エチレン−1−オクテンランダム共重合体等が挙げられ、好ましくはプロピレン−エチレンランダム共重合体、プロピレン−1−ブテンランダム共重合体、プロピレン−エチレン−1−ブテンランダム共重合体である。 Examples of the propylene-based random copolymer used as the propylene-based polymer in the present invention include a propylene-ethylene random copolymer and a propylene-α-olefin random copolymer. Examples of the propylene-α-olefin random copolymer include a propylene-1-butene random copolymer, a propylene-1-hexene random copolymer, a propylene-1-octene random copolymer, and a propylene-ethylene-1-. Examples thereof include a butene random copolymer, a propylene-ethylene-1-hexene random copolymer, a propylene-ethylene-1-octene random copolymer, and the like, preferably a propylene-ethylene random copolymer and a propylene-1-butene random. Copolymer, propylene-ethylene-1-butene random copolymer.

本発明でプロピレン系重合体として用いられるプロピレン系ランダム共重合体がプロピレン−エチレンランダム共重合体である場合、エチレン含有量は、得られる二軸延伸フィルムの加熱収縮率および剛性の観点から、好ましくは2.0質量%以下であり、より好ましくは1.0質量%以下であり、さらに好ましくは0.4質量%以下である。 When the propylene-based random copolymer used as the propylene-based polymer in the present invention is a propylene-ethylene random copolymer, the ethylene content is preferably from the viewpoint of the heat shrinkage rate and rigidity of the obtained biaxially stretched film. Is 2.0% by mass or less, more preferably 1.0% by mass or less, still more preferably 0.4% by mass or less.

本発明でプロピレン系重合体として用いられるプロピレン系ランダム共重合体がプロピレン−α−オレフィンランダム共重合体である場合、α−オレフィン含有量は、得られるポリプロピレン系延伸フィルムの加熱収縮率および剛性の観点から、好ましくは8.0質量%以下であり、より好ましくは3.0質量%以下であり、さらに好ましくは1.0質量%以下である。 When the propylene-based random copolymer used as the propylene-based polymer in the present invention is a propylene-α-olefin random copolymer, the α-olefin content is the heat shrinkage and rigidity of the obtained polypropylene-based stretched film. From the viewpoint, it is preferably 8.0% by mass or less, more preferably 3.0% by mass or less, and further preferably 1.0% by mass or less.

本発明でプロピレン系重合体として用いられるプロピレン系ランダム共重合体がプロピレン−エチレン−α−オレフィンランダム共重合体である場合、エチレンとα−オレフィンの含有量の合計は、得られる二軸延伸フィルムの加熱収縮率および剛性の観点から、好ましくは8.0質量%以下であり、より好ましくは3.0質量%以下であり、さらに好ましくは1.0質量%以下である。 When the propylene-based random copolymer used as the propylene-based polymer in the present invention is a propylene-ethylene-α-olefin random copolymer, the total content of ethylene and α-olefin is the obtained biaxially stretched film. From the viewpoint of the heat shrinkage rate and rigidity of the above, it is preferably 8.0% by mass or less, more preferably 3.0% by mass or less, and further preferably 1.0% by mass or less.

本発明で用いられるプロピレン系重合体の冷キシレン可溶部量(以下、CXSと略す。)は2.0質量%以下であり、好ましくは0.1質量%〜1.0質量%であり、より好ましくは0.3質量%〜1.0質量%である。CXSを上記範囲とすることにより、良好な延伸加工性を呈するとともに、得られる二軸延伸フィルムにおいて、高い剛性および高温下での優れた収縮率を発現させうるという効果がある。 The cold xylene-soluble portion (hereinafter, abbreviated as CXS) of the propylene-based polymer used in the present invention is 2.0% by mass or less, preferably 0.1% by mass to 1.0% by mass. More preferably, it is 0.3% by mass to 1.0% by mass. By setting CXS in the above range, it is possible to exhibit good stretchability and to exhibit high rigidity and excellent shrinkage rate at high temperature in the obtained biaxially stretched film.

本発明で用いられるプロピレン系重合体のメルトフローレート(以下、MFRと略す。)は1〜50(g/10分)であり、好ましくは1〜20(g/10分)であり、より好ましくは4〜20(g/10分)である。MFRが上記範囲にあるプロピレン系重合体を用いることにより、溶融状態のポリプロピレンが適度な粘度を有し、良好な延伸加工性を呈するとともに、得られる二軸延伸フィルムにおいて、高い剛性および高温下での優れた収縮率を発現させうるという効果がある。
尚、本発明においてMFRとは、JIS K7210−1:2014に規定されたA法に従って、温度230℃、荷重21.18Nで測定されるものである。
The melt flow rate (hereinafter abbreviated as MFR) of the propylene-based polymer used in the present invention is 1 to 50 (g / 10 minutes), preferably 1 to 20 (g / 10 minutes), more preferably. Is 4 to 20 (g / 10 minutes). By using a propylene-based polymer having an MFR in the above range, the molten polypropylene has an appropriate viscosity and exhibits good stretchability, and the obtained biaxially stretched film has high rigidity and high temperature. It has the effect of being able to develop an excellent shrinkage rate.
In the present invention, the MFR is measured at a temperature of 230 ° C. and a load of 21.18 N according to the method A specified in JIS K7210-1: 2014.

本発明で用いられるプロピレン系重合体組成物は、MFRの異なる複数種類のプロピレン系重合体を含むものを採用することができる。好ましい例として、該プロピレン系重合体組成物は、MFRが0.1g/10分〜15g/10分であるプロピレン系重合体(a)と、MFRが20g/10分〜500g/10分であるプロピレン系重合体(b)とを含むものとすることができる。 As the propylene-based polymer composition used in the present invention, one containing a plurality of types of propylene-based polymers having different MFRs can be adopted. As a preferred example, the propylene-based polymer composition has an MFR of 0.1 g / 10 min to 15 g / 10 min and a propylene-based polymer (a) having an MFR of 20 g / 10 min to 500 g / 10 min. It can contain the propylene-based polymer (b).

前記プロピレン系重合体組成物における前記プロピレン系重合体(a)およびプロピレン系重合体(b)の含有量は、前記プロピレン系重合体(a)および前記プロピレン系重合体(b)の合計含有量に対して、プロピレン系重合体(a)が50質量%〜90質量%、プロピレン系重合体(b)が10質量%〜50質量%であることが好ましく、プロピレン系重合体(a)が50質量%〜85質量%、プロピレン系重合体(b)が15質量%〜50質量%であることがより好ましい。
メルトフローレートの異なる複数種類のプロピレン系重合体を含むプロピレン系重合体組成物を用いることにより、延伸加工時の厚みムラが低減され、良好な延伸加工性を呈するとともに、得られる二軸延伸フィルムにおいて、高い剛性および高温下での優れた収縮率を発現させうるという効果がある。
The content of the propylene-based polymer (a) and the propylene-based polymer (b) in the propylene-based polymer composition is the total content of the propylene-based polymer (a) and the propylene-based polymer (b). On the other hand, the propylene-based polymer (a) is preferably 50% by mass to 90% by mass, the propylene-based polymer (b) is preferably 10% by mass to 50% by mass, and the propylene-based polymer (a) is 50% by mass. It is more preferable that the mass% to 85% by mass and the propylene-based polymer (b) are 15% by mass to 50% by mass.
By using a propylene-based polymer composition containing a plurality of types of propylene-based polymers having different melt flow rates, thickness unevenness during stretching is reduced, good stretching processability is exhibited, and the obtained biaxially stretched film is obtained. In, there is an effect that high rigidity and an excellent shrinkage rate under high temperature can be exhibited.

本発明で用いられるプロピレン系重合体組成物の冷キシレン可溶部量(CXS)は、2.0質量%以下であり、好ましくは0.1質量%〜1.0質量%であり、より好ましくは0.3質量%〜1.0質量%である。CXSを上記範囲とすることにより、良好な延伸加工性を呈するとともに、得られる二軸延伸フィルムにおいて、高い剛性および高温下での優れた収縮率を発現させうるという効果がある。 The cold xylene-soluble portion (CXS) of the propylene-based polymer composition used in the present invention is 2.0% by mass or less, preferably 0.1% by mass to 1.0% by mass, more preferably. Is 0.3% by mass to 1.0% by mass. By setting CXS in the above range, it is possible to exhibit good stretchability and to exhibit high rigidity and excellent shrinkage rate at high temperature in the obtained biaxially stretched film.

プロピレン系重合体組成物を製造する方法としては、プロピレン系重合体(a)とプロピレン系重合体(b)とをそれぞれ個別に製造し、それぞれ個別に製造されたプロピレン系重合体(a)とプロピレン系重合体(b)とを混合してプロピレン系重合体組成物とする方法が挙げられる。プロピレン系重合体(a)とプロピレン系重合体(b)をそれぞれ個別に製造する方法としては、公知の重合方法が挙げられる。例えば、不活性溶媒の存在下で行われる溶媒重合法、液状のモノマーの存在下で行われる塊状重合法、実質上液状の媒体の不存在下で行われる気相重合法等が挙げられる。好ましくは気相重合法である。また、上記の重合方法を2種類以上組み合わせる重合方法、2段以上の多段重合の方法等も挙げられる。 As a method for producing the propylene-based polymer composition, the propylene-based polymer (a) and the propylene-based polymer (b) are individually produced, and each of the individually produced propylene-based polymer (a) and the propylene-based polymer (a) are produced. Examples thereof include a method of mixing the propylene-based polymer (b) with the propylene-based polymer (b) to obtain a propylene-based polymer composition. Examples of the method for individually producing the propylene-based polymer (a) and the propylene-based polymer (b) include known polymerization methods. For example, a solvent polymerization method performed in the presence of an inert solvent, a massive polymerization method performed in the presence of a liquid monomer, a gas phase polymerization method performed in the absence of a substantially liquid medium, and the like can be mentioned. A gas phase polymerization method is preferable. Further, a polymerization method in which two or more kinds of the above polymerization methods are combined, a method of multi-stage polymerization of two or more stages, and the like can be mentioned.

個別に製造されたプロピレン系重合体(a)とプロピレン系重合体(b)を混合する方法としては、これら重合体(a)と重合体(b)が均一に分散する方法であればよい。例えば、重合体(a)と重合体(b)をリボンブレンダー、ヘンシェルミキサー、タンブラーミキサー等で混合し、その混合物を押出し機等で溶融混練する方法、重合体(a)と重合体(b)をそれぞれ個別に溶融混練しペレット化し、ペレット化された重合体(a)と重合体(b)を上記と同様の方法で混合し、さらに溶融混練する方法、重合体(a)と重合体(b)をそれぞれ個別に溶融混練しペレット化し、ペレット化された重合体(a)と重合体(b)をドライブレンド等でブレンドした後、直接フィルム加工機で混合する方法、重合体(a)と重合体(b)をそれぞれ個別に溶融混練しペレット化し、ペレット化された重合体(a)と重合体(b)を個別にフィルム加工機の押出機にフィードして混合する方法等が挙げられる。また、プロピレン系重合体(a)100重量部に対して、プロピレン系重合体(b)を1〜99重量部含むマスターバッチをあらかじめ作製し、所定の濃度となるように適宜混合する方法等も挙げられる。 The method of mixing the individually produced propylene-based polymer (a) and the propylene-based polymer (b) may be any method in which the polymer (a) and the polymer (b) are uniformly dispersed. For example, a method of mixing the polymer (a) and the polymer (b) with a ribbon blender, a Henschel mixer, a tumbler mixer or the like, and melt-kneading the mixture with an extruder or the like, the polymer (a) and the polymer (b) Are individually melt-kneaded and pelletized, and the pelletized polymer (a) and polymer (b) are mixed in the same manner as described above, and further melt-kneaded, the polymer (a) and the polymer ( A method in which b) is individually melt-kneaded and pelletized, the pelletized polymer (a) and the polymer (b) are blended by a dry blend or the like, and then directly mixed by a film processing machine, the polymer (a). And the polymer (b) are individually melt-kneaded and pelletized, and the pelletized polymer (a) and the polymer (b) are individually fed to the extruder of the film processing machine and mixed. Be done. Further, there is also a method in which a master batch containing 1 to 99 parts by weight of the propylene-based polymer (b) is prepared in advance with respect to 100 parts by weight of the propylene-based polymer (a) and appropriately mixed so as to have a predetermined concentration. Can be mentioned.

また、個別に製造されたプロピレン系重合体(a)とプロピレン系重合体(b)を混合する際に、必要に応じて、安定剤、滑剤、帯電防止剤、および抗ブロッキング剤、無機または有機の各種フィラー等を添加してもよい。 In addition, when mixing the individually produced propylene-based polymer (a) and the propylene-based polymer (b), if necessary, a stabilizer, a lubricant, an antistatic agent, and an anti-blocking agent, inorganic or organic. Various fillers and the like may be added.

本発明で用いられるプロピレン系重合体(a)とプロピレン系重合体(b)の重合に用いられる触媒としては、これらを個別に重合する場合においても多段重合法を用いる場合においても、プロピレンの立体規則性重合用触媒が用いられる。 The catalyst used for the polymerization of the propylene-based polymer (a) and the propylene-based polymer (b) used in the present invention is a three-dimensional propylene regardless of whether they are individually polymerized or the multi-stage polymerization method is used. A catalyst for regular polymerization is used.

プロピレンの立体規則性重合用触媒としては、例えば、三塩化チタン触媒、チタン、マグネシウム、ハロゲン、および電子供与体を必須成分とするTi−Mg系触媒等の固体触媒成分に、有機アルミニウム化合物や必要に応じて電子供与性化合物等の第3成分を組み合わせた触媒系、メタロセン系触媒等が挙げられる。 Examples of the catalyst for stereoregular polymerization of propylene include an organic aluminum compound and necessary as a solid catalyst component such as a titanium trichloride catalyst, a Ti-Mg-based catalyst containing titanium, magnesium, halogen, and an electron donor as essential components. Examples thereof include a catalyst system in which a third component such as an electron donating compound is combined, a metallocene catalyst, and the like.

好ましくは、マグネシウム、チタン、ハロゲンおよび電子供与体を必須成分とする固体触媒成分、有機アルミニウム化合物および電子供与性化合物を組み合わせた触媒系であり、その具体例としては、特開昭61−218606号公報、特開昭61−287904号公報、特開平7−216017号公報、特開2004−182876等に記載された触媒系が挙げられる。 Preferably, it is a catalyst system in which a solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, an organoaluminum compound and an electron donor compound are combined, and specific examples thereof include JP-A-61-218606. Examples thereof include catalyst systems described in JP-A-61-287904, JP-A-7-216017, JP-A-2004-182876 and the like.

本発明の二軸延伸フィルムは、MFRが1g/10分〜50g/10分であり、且つCXSが2.0質量%以下であるプロピレン系重合体またはプロピレン系重合体組成物を用いて二軸延伸することによって得られるものである。二軸延伸の具体的な方法については、後述する。 The biaxially stretched film of the present invention uses a propylene-based polymer or a propylene-based polymer composition having an MFR of 1 g / 10 minutes to 50 g / 10 minutes and a CXS of 2.0% by mass or less. It is obtained by stretching. The specific method of biaxial stretching will be described later.

本発明の二軸延伸フィルムは、広角X線散乱法を用いて、該二軸延伸フィルムのMD方向と直交する二軸延伸フィルムの断面にX線を入射して測定されるプロピレン系重合体のα型結晶の040面の散乱強度を、方位角に対してプロットした時の最大ピークの半値幅が13.0°以下であり、好ましくは6.0°〜12.0°以下、より好ましくは6.0°〜9.0°である。
前記半値幅が上記の範囲内であれば、TD方向における結晶配向度が高く、剛性と高温下での熱収縮率のバランスに優れるという効果がある。
なお、本明細書において、二軸延伸フィルムのMD方向とは、二軸延伸フィルムを製造する際の流れ方向を意味し、TD方向とはMD方向に直交する方向(二軸延伸フィルムの幅方向ともいう)を意味する。
The biaxially stretched film of the present invention is a propylene-based polymer measured by injecting X-rays into a cross section of the biaxially stretched film orthogonal to the MD direction of the biaxially stretched film using a wide-angle X-ray scattering method. The half-value width of the maximum peak when the scattering intensity of the 040 plane of the α-type crystal is plotted against the azimuth angle is 13.0 ° or less, preferably 6.0 ° to 12.0 ° or less, more preferably. It is 6.0 ° to 9.0 °.
When the half width is within the above range, the degree of crystal orientation in the TD direction is high, and there is an effect that the balance between rigidity and heat shrinkage at high temperature is excellent.
In the present specification, the MD direction of the biaxially stretched film means the flow direction when the biaxially stretched film is manufactured, and the TD direction is a direction orthogonal to the MD direction (width direction of the biaxially stretched film). Also called).

本発明の二軸延伸フィルムは、下記式(I)を満たすものである。
0.42×E×(1−X)≦600 (I)
(式中、Eは、温度70℃で測定される二軸延伸フィルムのTD方向の複素弾性率(MPa)を示し、Xは、下記式(II)で算出される値を示す。)
X=14.18−12.34/D (II)
(式中、Dは、二軸延伸フィルムの密度(g/cm)を示す。)
The biaxially stretched film of the present invention satisfies the following formula (I).
0.42 x E x (1-X) ≤ 600 (I)
(In the formula, E represents the complex elastic modulus (MPa) in the TD direction of the biaxially stretched film measured at a temperature of 70 ° C., and X represents the value calculated by the following formula (II).)
X = 14.18-12.34 / D (II)
(In the formula, D indicates the density (g / cm 3 ) of the biaxially stretched film.)

前記式(II)におけるXは、プロピレン系重合体又はプロピレン系重合体組成物を二軸延伸して得られた二軸延伸フィルムの結晶化度を表し、該二軸延伸フィルムの密度D(g/cm)に基づき前記式(II)の右辺によって算出される値である。
前記式(I)は、この結晶化度Xと二軸延伸フィルムのTD方向(横方向)の複素弾性率Eが所定の関係を満たすことを意味しており、具体的には、結晶化度Xと二軸延伸フィルムのTD方向の複素弾性率Eとの関数である前記式(I)の左辺の値が、600以下であることを規定する。
X in the formula (II) represents the crystallinity of the biaxially stretched film obtained by biaxially stretching the propylene-based polymer or the propylene-based polymer composition, and the density D (g) of the biaxially stretched film. It is a value calculated by the right side of the above formula (II) based on / cm 3).
The formula (I) means that the crystallinity X and the complex elastic modulus E in the TD direction (lateral direction) of the biaxially stretched film satisfy a predetermined relationship, and specifically, the crystallinity. It is specified that the value on the left side of the above formula (I), which is a function of X and the complex elastic modulus E in the TD direction of the biaxially stretched film, is 600 or less.

プロピレン系重合体又はプロピレン系重合体組成物を二軸延伸して得られた二軸延伸フィルムは、延伸によって整列したプロピレン系重合体の結晶部分と、該結晶部分同士を繋ぐ非晶質部分(タイ分子)とを有していると考えられる。延伸により非晶質部分(タイ分子)がTD方向に高配向した二軸延伸フィルムでは、高温下では非晶質部分(タイ分子)が収縮するため、二軸延伸フィルムの加熱収縮率が大きくなると考えられる。また、非晶質部分(タイ分子)がTD方向に高配向すると、結晶化度Xが小さいにも関わらず複素弾性率Eが大きくなりうる。すなわち、前記式(1)の左辺の値が大きいほど、非晶質部分(タイ分子)がTD方向に高配向していると考えられ、加熱収縮率が大きい二軸延伸フィルムとなる。 The biaxially stretched film obtained by biaxially stretching the propylene-based polymer or the propylene-based polymer composition has a crystal portion of the propylene-based polymer aligned by stretching and an amorphous portion (an amorphous portion connecting the crystal portions). It is considered to have a Thai molecule). In a biaxially stretched film in which the amorphous portion (tie molecule) is highly oriented in the TD direction due to stretching, the amorphous portion (tie molecule) shrinks at a high temperature, so that the heat shrinkage rate of the biaxially stretched film increases. Conceivable. Further, when the amorphous portion (tie molecule) is highly oriented in the TD direction, the complex elastic modulus E can be increased even though the crystallinity X is small. That is, it is considered that the larger the value on the left side of the above formula (1) is, the more the amorphous portion (tie molecule) is oriented in the TD direction, and the biaxially stretched film has a large heat shrinkage rate.

本発明の二軸延伸フィルムは、前記式(1)の左辺の値を600以下とし、好ましくは、前記式(1)の左辺の値が300以上500以下、即ち、下記式(I’)を満たすものとする。
300≦0.42×E×(1−X)≦500 (I’)
In the biaxially stretched film of the present invention, the value on the left side of the formula (1) is 600 or less, and preferably the value on the left side of the formula (1) is 300 or more and 500 or less, that is, the following formula (I'). Satisfy.
300 ≤ 0.42 x E x (1-X) ≤ 500 (I')

また、本発明の二軸延伸フィルムは、前記式(1)又は前記式(I’)における複素弾性率Eが2000MPa〜6000MPaであることが好ましい。また、本発明の二軸延伸フィルムは、前記式(II)における密度Dが0.900g/cm〜0.925g/cmであることが好ましい。 Further, the biaxially stretched film of the present invention preferably has a complex elastic modulus E in the formula (1) or the formula (I') of 2000 MPa to 6000 MPa. The biaxially oriented film of the present invention is preferably the density D in the formula (II) is 0.900g / cm 3 ~0.925g / cm 3 .

また、本発明の二軸延伸フィルムは、厚みが10μm〜70μmであることが好ましい。 Further, the biaxially stretched film of the present invention preferably has a thickness of 10 μm to 70 μm.

本発明の多層フィルムは、少なくとも一層の前記二軸延伸フィルムを含み、該二軸延伸フィルムに任意の層を積層させたものである。具体的には、シーラント層、ガスバリア層、接着層、印刷層等の任意の層を前記二軸延伸フィルムと積層して多層フィルムを構成することができる。
中でも、オレフィン系のフィルムを用いたシーラント層と前記二軸延伸フィルムとを積層することが好ましく、得られた多層フィルムがリサイクルしやすいという効果がある。
任意の層を前記二軸延伸フィルムと積層した多層フィルムを作製する方法としては、通常用いられる押出ラミネート法、熱ラミネート法、ドライラミネート法等が挙げられる。
The multilayer film of the present invention contains at least one layer of the biaxially stretched film, and an arbitrary layer is laminated on the biaxially stretched film. Specifically, an arbitrary layer such as a sealant layer, a gas barrier layer, an adhesive layer, and a printing layer can be laminated with the biaxially stretched film to form a multilayer film.
Above all, it is preferable to laminate the sealant layer using the olefin-based film and the biaxially stretched film, and there is an effect that the obtained multilayer film is easy to recycle.
Examples of a method for producing a multilayer film in which an arbitrary layer is laminated with the biaxially stretched film include an extrusion laminating method, a thermal laminating method, and a dry laminating method, which are usually used.

本発明の包装袋は、前記二軸延伸フィルムを含んで構成されたものである。該包装袋は、食品、衣料品、雑貨等の任意の包装対象物を包装する用途として使用し得る。 The packaging bag of the present invention is configured to include the biaxially stretched film. The packaging bag can be used for packaging any packaging object such as food, clothing, and miscellaneous goods.

本発明の二軸延伸フィルムの製造方法としては、逐次二軸延伸方式や同時二軸延伸方式による二軸延伸フィルムの製造方法を挙げることができる。 Examples of the method for producing a biaxially stretched film of the present invention include a method for producing a biaxially stretched film by a sequential biaxial stretching method and a simultaneous biaxial stretching method.

逐次二軸延伸方式においては、MFRが1g/10分〜50g/10分であり、且つCXSが2.0質量%以下であるプロピレン系重合体またはプロピレン系重合体組成物を、押出機を用いて加熱溶融し、Tダイより押出し、冷却ロール上に押し出すことによってシート状に冷却固定し、未延伸シートを得る工程と、得られた未延伸シートを、一連の延伸ロールを用いてMD方向に3倍〜12倍に延伸することにより、一軸延伸フィルムを得る工程と、得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、予熱部、延伸部、熱処理部を備えた加熱炉内にて、一軸延伸フィルムをTD方向に4倍〜20倍に延伸した後、該2列のチャックの間隔を狭めることにより該TD方向に16%〜30%緩和(リラックス)させることにより二軸延伸フィルムを得る工程と、を含むことができる。また、必要に応じてコロナ処理等を行う工程を含む。 In the sequential biaxial stretching method, a propylene-based polymer or a propylene-based polymer composition having an MFR of 1 g / 10 minutes to 50 g / 10 minutes and a CXS of 2.0% by mass or less is produced by using an extruder. Heat-melted, extruded from a T-die, cooled and fixed in a sheet shape by extruding onto a cooling roll to obtain an unstretched sheet, and the obtained unstretched sheet was subjected to a series of stretching rolls in the MD direction. A step of obtaining a uniaxially stretched film by stretching 3 to 12 times, and grasping both ends of the obtained uniaxially stretched film with two rows of chucks arranged along the MD direction, a preheating part, a stretched part, and a heat treatment. After stretching the uniaxially stretched film 4 to 20 times in the TD direction in a heating furnace equipped with a portion, the distance between the two rows of chucks is narrowed to relax 16% to 30% in the TD direction (relaxation). ) To obtain a biaxially stretched film, and the like. In addition, a step of performing corona treatment or the like as necessary is included.

逐次二軸延伸方式において、プロピレン系重合体又はプロピレン系重合体組成物を押出機で加熱溶融する際の溶融温度は230〜290℃が好ましい。Tダイより押出されたプロピレン系重合体又はプロピレン系重合体組成物をシート状に冷却固定する際の冷却ロールの温度は10℃〜60℃が好ましい。未延伸シートをMD方向に延伸する際の延伸ロールの温度は110〜165℃が好ましい。一軸延伸フィルムをTD方向に延伸する際の加熱温度は150〜200℃が好ましく、TD方向に緩和する際の加熱温度は150〜200℃が好ましい。 In the sequential biaxial stretching method, the melting temperature when the propylene-based polymer or the propylene-based polymer composition is heated and melted by an extruder is preferably 230 to 290 ° C. The temperature of the cooling roll when the propylene-based polymer or the propylene-based polymer composition extruded from the T-die is cooled and fixed in the form of a sheet is preferably 10 ° C. to 60 ° C. The temperature of the stretching roll when the unstretched sheet is stretched in the MD direction is preferably 110 to 165 ° C. The heating temperature when the uniaxially stretched film is stretched in the TD direction is preferably 150 to 200 ° C., and the heating temperature when relaxing in the TD direction is preferably 150 to 200 ° C.

一方、同時二軸延伸方式においては、MFRが1g/10分〜50g/10分であり、且つCXSが2.0質量%以下であるプロピレン系重合体またはプロピレン系重合体組成物を、押出機を用いて加熱溶融し、Tダイより押出し、冷却ロール上に押し出すことによってシート状に冷却固定し、未延伸シートを得る工程と、得られたシートの両端を流れ方向に沿って並んだ2列のチャックでそれぞれ掴み、予熱部、延伸部、および熱処理部からなる加熱炉にて、上記2列のチャックのTD方向の間隔と各列内の個々のチャックのMD方向の間隔を広げることにより、MD方向とTD方向へ同時に延伸し、その後TD方向に16%〜30%緩和させることにより二軸延伸フィルムを得る工程とを含み、必要に応じてコロナ処理等を行う工程を含む。
なお、同時二軸延伸方式における冷却ロールの温度、縦方向および横方向への延伸倍率と延伸時の加熱温度、並びに緩和の際の緩和率および加熱温度については、前記逐次二軸延伸方式における各条件と同じである。
On the other hand, in the simultaneous biaxial stretching method, a propylene-based polymer or a propylene-based polymer composition having an MFR of 1 g / 10 minutes to 50 g / 10 minutes and a CXS of 2.0% by mass or less is extruded. A process of obtaining an unstretched sheet by heating and melting using In a heating furnace consisting of a preheating part, a stretching part, and a heat treatment part, the distance between the two rows of chucks in the TD direction and the distance between the individual chucks in each row in the MD direction are widened. It includes a step of simultaneously stretching in the MD direction and the TD direction and then relaxing by 16% to 30% in the TD direction to obtain a biaxially stretched film, and includes a step of performing corona treatment or the like as necessary.
The temperature of the cooling roll in the simultaneous biaxial stretching method, the stretching ratio in the vertical and horizontal directions, the heating temperature at the time of stretching, and the relaxation rate and the heating temperature at the time of relaxation are described in each of the sequential biaxial stretching methods. Same as the condition.

逐次二軸延伸方式および同時二軸延伸方式において、フィルムを緩和させる際の緩和率は下限値が16%であり、好ましくは下限値が18%である。該下限値未満の緩和率では、加熱時の収縮率が高くなり、耐熱性に優れた二軸延伸フィルムが得られない。また、緩和率の上限値は30%であり、好ましくは上限値は25%である。該上限値を超える緩和率では、フィルムの厚みムラが大きくなりやすい。 In the sequential biaxial stretching method and the simultaneous biaxial stretching method, the lower limit value of the relaxation rate when relaxing the film is 16%, preferably the lower limit value is 18%. If the relaxation rate is less than the lower limit, the shrinkage rate during heating becomes high, and a biaxially stretched film having excellent heat resistance cannot be obtained. The upper limit of the relaxation rate is 30%, preferably the upper limit is 25%. If the relaxation rate exceeds the upper limit value, the thickness unevenness of the film tends to increase.

なお、本発明において緩和率Rは、下記式(III)により求められるものである。
R=(L−L)/L×100 (III)
(式中、Lはフィルムを緩和する前のTD方向におけるチャック間の距離、Lはフィルムを緩和した後のTD方向におけるチャック間の距離を示す)
In the present invention, the relaxation rate R is determined by the following formula (III).
R = (L 1- L 2 ) / L 1 x 100 (III)
(In the equation, L 1 indicates the distance between the chucks in the TD direction before the film is relaxed, and L 2 indicates the distance between the chucks in the TD direction after the film is relaxed.)

実施例および比較例における各項目の測定値は、下記の方法で測定した。 The measured values of each item in Examples and Comparative Examples were measured by the following methods.

(1)メルトフローレート(MFR、単位:g/10分)
プロピレン系重合体およびプロピレン系重合体組成物のMFRは、JIS K7210−1:2014に規定されたA法に従って、温度230℃、荷重21.18Nで測定した。
(1) Melt flow rate (MFR, unit: g / 10 minutes)
The MFR of the propylene-based polymer and the propylene-based polymer composition was measured at a temperature of 230 ° C. and a load of 21.18 N according to the method A specified in JIS K7210-1: 2014.

(2)冷キシレン可溶部量(CXS、単位:質量%)
プロピレン系重合体1gまたはプロピレン系重合体組成物1gを、沸騰キシレン100mlに完全に溶解させた後、20℃に降温し、4時間放置した。得られた混合物を析出物と溶液とに濾別した。得られた濾液を乾固した後、減圧下70℃で乾燥し、残存物を得た。得られた残存物の重量を測定して、冷キシレン可溶部量(CXS)を求めた。
(2) Amount of cold xylene-soluble part (CXS, unit: mass%)
After completely dissolving 1 g of the propylene-based polymer or 1 g of the propylene-based polymer composition in 100 ml of boiling xylene, the temperature was lowered to 20 ° C., and the mixture was allowed to stand for 4 hours. The resulting mixture was filtered off into a precipitate and a solution. The obtained filtrate was dried to dryness and then dried under reduced pressure at 70 ° C. to obtain a residue. The weight of the obtained residue was measured to determine the amount of cold xylene soluble part (CXS).

(3)広角X線散乱
緩和された二軸延伸フィルムについて、以下の条件で広角X線散乱測定を行った。
・機種:株式会社リガク製 Nano Viewer
・管球:Cu―Kα
・電圧:40kV
・電流:20mA
・ビーム径:0.25mmφ
・検出器:PILATUS 100k
(3) Wide-angle X-ray scattering Wide-angle X-ray scattering measurement was performed on the relaxed biaxially stretched film under the following conditions.
・ Model: Nano Viewer manufactured by Rigaku Co., Ltd.
・ Tube: Cu-Kα
・ Voltage: 40kV
・ Current: 20mA
・ Beam diameter: 0.25 mmφ
・ Detector: PILATUS 100k

二軸延伸フィルムのTD方向と平行にフィルムを切断し、MD方向の幅が1mmの試験片を作製した。MD方向と直交する試験片の断面に、MD方向と平行となるようにX線を入射し、プロピレン系重合体の広角X線散乱を測定した。回折角2θが15°〜17°に観測されるポリプロピレン系重合体のα型結晶の040面の散乱強度を、方位角に対してプロットした時の最大となるピークの半値幅を測定した。 The film was cut in parallel with the TD direction of the biaxially stretched film to prepare a test piece having a width of 1 mm in the MD direction. X-rays were incident on the cross section of the test piece orthogonal to the MD direction so as to be parallel to the MD direction, and the wide-angle X-ray scattering of the propylene-based polymer was measured. The half width of the maximum peak when the scattering intensity of the 040 plane of the α-type crystal of the polypropylene polymer observed at a diffraction angle 2θ of 15 ° to 17 ° was plotted against the azimuth angle was measured.

(4−1)複素弾性率(E、単位:MPa)
複素弾性率は、自動動的粘弾性測定機(RSA−G2、TAインスツルメント製)を用いて測定した。二軸延伸フィルムから、TD方向に50mm、MD方向に5mmの試験片を採取した。得られた試験片を、チャック間距離が20mmとなるようチャックに固定し、−50℃まで冷却した。その後、TD方向に10gの引張荷重を印加した状態で、ひずみ量0.05%、振動数5Hzの振動を与え、−50℃〜180℃まで3℃/分で昇温しながら、複素弾性率の温度依存性を測定した。得られた複素弾性率の温度依存性カーブから、70℃における複素弾性率を得た。
(4-1) Complex elastic modulus (E, unit: MPa)
The complex elastic modulus was measured using an automatic dynamic viscoelasticity measuring machine (RSA-G2, manufactured by TA Instruments). A test piece of 50 mm in the TD direction and 5 mm in the MD direction was collected from the biaxially stretched film. The obtained test piece was fixed to the chuck so that the distance between the chucks was 20 mm, and cooled to −50 ° C. After that, with a tensile load of 10 g applied in the TD direction, vibration with a strain amount of 0.05% and a frequency of 5 Hz was applied, and the complex elastic modulus was raised from -50 ° C to 180 ° C at 3 ° C / min. The temperature dependence of was measured. From the temperature-dependent curve of the obtained complex elastic modulus, the complex elastic modulus at 70 ° C. was obtained.

(4−2)密度(D、単位:g/cm
二軸延伸フィルムの密度は、JIS K7112−1999に記載のD法(水/エタノール)に従って、密度勾配管法により測定した。
(4-2) Density (D, unit: g / cm 3 )
The density of the biaxially stretched film was measured by the density gradient tube method according to the D method (water / ethanol) described in JIS K7112-1999.

(5)フィルム厚み(単位:μm)
二軸延伸フィルムの厚みは、JIS K7130−1999に記載のA法に従って、接触式のフィルム厚み計で測定した。
(5) Film thickness (unit: μm)
The thickness of the biaxially stretched film was measured with a contact-type film thickness gauge according to the method A described in JIS K7130-199.

(6)加熱収縮率(単位:%)
二軸延伸フィルムの長軸がMD方向と平行になるように、A4サイズ(縦297mm×横210mm)のフィルムを採取し、MD方向およびTD方向にそれぞれ200mmの標線を引き、150℃のオーブン中に吊るして30分間保持した。その後、フィルムを取り出し、室温にて30分間冷却した後に、各標線長さを測定した。各方向に対する加熱収縮率を、次の計算式から算出した。

加熱収縮率(%)={(200−加熱後の標線長さ(mm))/200}×100

加熱収縮率が小さいことは、高温下での寸法安定性に優れることを示す。
(6) Heat shrinkage rate (unit:%)
A4 size (length 297 mm x width 210 mm) film is sampled so that the long axis of the biaxially stretched film is parallel to the MD direction, and 200 mm marking lines are drawn in the MD and TD directions, respectively, and an oven at 150 ° C. It was hung inside and held for 30 minutes. Then, the film was taken out, cooled at room temperature for 30 minutes, and then the length of each marked line was measured. The heat shrinkage rate in each direction was calculated from the following formula.

Heat shrinkage rate (%) = {(200-marked line length after heating (mm)) / 200} x 100

A small heat shrinkage indicates excellent dimensional stability at high temperatures.

実施例および比較例で用いた各成分は、以下のとおりである。 The components used in the examples and comparative examples are as follows.

<プロピレン系重合体1>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度0.14mol%の環境下で、プロピレンを重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、ステアリン酸カルシウム(堺化学工業株式会社製)0.10質量%、IRGANOX1010(BASFジャパン株式会社製)0.15質量%、IRGAFOS168(BASFジャパン株式会社製)0.15質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体1を得た。得られたプロピレン系重合体1のMFRは2.3g/10分、CXSは0.4質量%であった。
<Propene polymer 1>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene is polymerized in an environment with a hydrogen concentration of 0.14 mol% by a vapor phase polymerization method to obtain a propylene-based polymer. Got Calcium stearate (manufactured by Sakai Chemical Industry Co., Ltd.) 0.10% by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.15% by mass, IRGAFOS168 (manufactured by BASF Japan Ltd.) with respect to 100 parts by mass of the obtained propylene polymer. (Manufactured) After blending 0.15% by mass, melt extrusion was carried out to obtain a pellet-shaped propylene-based polymer 1. The MFR of the obtained propylene-based polymer 1 was 2.3 g / 10 minutes, and the CXS was 0.4% by mass.

<プロピレン系重合体2>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度10.0mol%の環境下でプロピレンを重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、DHT−4C(協和化学工業株式会社製)0.01質量%、IRGANOX1010(BASFジャパン株式会社製)0.13質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体2を得た。得られたプロピレン系重合体2のMFRは100g/10分、CXSは0.4質量%であった。
<Propene polymer 2>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene is polymerized in an environment with a hydrogen concentration of 10.0 mol% by a vapor phase polymerization method to obtain a propylene-based polymer. Obtained. DHT-4C (manufactured by Kyowa Chemical Industry Co., Ltd.) 0.01% by mass and IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.13% by mass were added to 100 parts by mass of the obtained propylene polymer, and then melted. Extrusion was carried out to obtain a pellet-shaped propylene-based polymer 2. The MFR of the obtained propylene-based polymer 2 was 100 g / 10 minutes, and the CXS was 0.4% by mass.

<プロピレン系重合体3>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度0.95mol%の環境下でプロピレンを重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、カルテックLT(鈴木工業株式会社製)0.002質量%、IRGANOX1010(BASFジャパン株式会社製)0.15質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体3を得た。得られたプロピレン系重合体3のMFRは9.5g/10分、CXSは0.4質量%であった。
<Propene polymer 3>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene is polymerized in an environment with a hydrogen concentration of 0.95 mol% by a vapor phase polymerization method to obtain a propylene-based polymer. Obtained. After blending 0.002% by mass of Caltec LT (manufactured by Suzuki Industries, Ltd.) and 0.15% by mass of IRGANOX1010 (manufactured by BASF Japan Co., Ltd.) with 100 parts by mass of the obtained propylene-based polymer, melt extrusion is performed. This was carried out to obtain a pellet-shaped propylene-based polymer 3. The MFR of the obtained propylene-based polymer 3 was 9.5 g / 10 minutes, and the CXS was 0.4% by mass.

<プロピレン系重合体4>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度2.25mol%の環境下でプロピレンを重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、ステアリン酸カルシウム(堺化学工業株式会社製)0.05質量%、IRGANOX1010(BASFジャパン株式会社製)0.05質量%、IRGAFOS168(BASFジャパン株式会社製)0.05質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体4を得た。得られたプロピレン系重合体4のMFRは19.5g/10分、CXSは0.7質量%であった。
<Propene polymer 4>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene is polymerized in an environment with a hydrogen concentration of 2.25 mol% by a vapor phase polymerization method to obtain a propylene-based polymer. Obtained. Calcium stearate (manufactured by Sakai Chemical Industry Co., Ltd.) 0.05% by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.05% by mass, IRGAFOS168 (manufactured by BASF Japan Ltd.) with respect to 100 parts by mass of the obtained propylene polymer. (Manufactured) After blending 0.05% by mass, melt extrusion was carried out to obtain a pellet-shaped propylene-based polymer 4. The MFR of the obtained propylene-based polymer 4 was 19.5 g / 10 minutes, and the CXS was 0.7% by mass.

<プロピレン系重合体5>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてn−プロピルメチルジメトキシシランとシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度0.06mol%の環境下でプロピレンを重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、ステアリン酸カルシウム(堺化学工業株式会社製)0.05質量%、DHT−4C(協和化学工業株式会社製)0.005質量%、IRGANOX1010(BASFジャパン株式会社製)0.15質量%、IRGAFOS168(BASFジャパン株式会社製)0.10質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体5を得た。プロピレン系重合体5のMFRは2.2g/10分、CXSは2.9質量%であった。
<Propene polymer 5>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and n-propylmethyldimethoxysilane and cyclohexylethyldimethoxysilane as external donors, propylene is polymerized in an environment with a hydrogen concentration of 0.06 mol% by a vapor phase polymerization method. Then, a propylene-based polymer was obtained. Calcium stearate (manufactured by Sakai Chemical Industry Co., Ltd.) 0.05% by mass, DHT-4C (manufactured by Kyowa Chemical Industry Co., Ltd.) 0.005% by mass, IRGANOX1010 (BASF) with respect to 100 parts by mass of the obtained propylene-based polymer. After blending 0.15% by mass (manufactured by Japan Co., Ltd.) and 0.10% by mass of IRGAFOS168 (manufactured by BASF Japan Co., Ltd.), melt extrusion was performed to obtain a pellet-shaped propylene-based polymer 5. The MFR of the propylene-based polymer 5 was 2.2 g / 10 minutes, and the CXS was 2.9% by mass.

<プロピレン系重合体6>
チーグラー・ナッタ型触媒と、助触媒としてトリエチルアルミニウム、外部ドナーとしてシクロヘキシルエチルジメトキシシランを用いて、気相重合法により、水素濃度0.04mol%、エチレン0.1mol%の環境下でプロピレンとエチレンを共重合し、プロピレン系重合体を得た。得られたプロピレン系重合体100質量部に対して、DHT−4C(協和化学工業株式会社製)0.01質量%、IRGANOX1010(BASFジャパン株式会社製)0.18質量%、IRGAFOS168(BASFジャパン株式会社製)0.22質量%を配合した後、溶融押出を行って、ペレット状のプロピレン系重合体6を得た。プロピレン系重合体6のMFRは0.5g/10分、CXSは0.5質量%であった。
<Propene polymer 6>
Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene and ethylene were produced in an environment with a hydrogen concentration of 0.04 mol% and ethylene of 0.1 mol% by a vapor phase polymerization method. Copolymerization was carried out to obtain a propylene-based polymer. DHT-4C (manufactured by Kyowa Chemical Industry Co., Ltd.) 0.01% by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.18% by mass, IRGAFOS168 (BASF Japan Ltd.) with respect to 100 parts by mass of the obtained propylene-based polymer. After blending 0.22% by mass (manufactured by the company), melt extrusion was carried out to obtain a pellet-shaped propylene-based polymer 6. The MFR of the propylene-based polymer 6 was 0.5 g / 10 minutes, and the CXS was 0.5% by mass.

<プロピレン系重合体組成物1>
上記のプロピレン系重合体1(70質量%)と上記のプロピレン系重合体2(30質量%)とをヘンシェルミキサーを用いて混合した後、溶融押出を行って、ペレット状のプロピレン系重合体組成物1を得た。得られたプロピレン系重合体組成物1のMFRは7.4g/10分、CXSは0.7質量%であった。
<Propylene-based polymer composition 1>
The above-mentioned propylene-based polymer 1 (70% by mass) and the above-mentioned propylene-based polymer 2 (30% by mass) are mixed using a Henshell mixer and then melt-extruded to form a pellet-like propylene-based polymer composition. I got the thing 1. The MFR of the obtained propylene-based polymer composition 1 was 7.4 g / 10 minutes, and the CXS was 0.7% by mass.

<プロピレン系重合体組成物2>
上記のプロピレン系重合体1(50質量%)と上記のプロピレン系重合体2(50質量%)とをヘンシェルミキサーを用いて混合した後、溶融押出を行って、ペレット状のプロピレン系重合体組成物2を得た。得られたプロピレン系重合体組成物2のMFRは13.8g/10分、CXSは0.8質量%であった。
<Propene-based polymer composition 2>
The above-mentioned propylene-based polymer 1 (50% by mass) and the above-mentioned propylene-based polymer 2 (50% by mass) are mixed using a Henshell mixer and then melt-extruded to form a pellet-shaped propylene-based polymer composition. I got the thing 2. The MFR of the obtained propylene-based polymer composition 2 was 13.8 g / 10 minutes, and the CXS was 0.8% by mass.

<実施例1>
プロピレン系重合体1を、スクリュー径65mmφの押出機を備えたTダイ製膜機を用いて、樹脂温度280℃で加熱溶融し、30℃の冷却ロール上に押し出すことにより、未延伸シートを得た。得られた未延伸シートを、152℃に加熱した延伸ロールを用いて、MD方向に5倍に延伸することにより、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に8倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、MD方向に沿って並んだ2列のチャックで掴み、165℃に加熱した加熱炉内にて、上記2列のチャック間隔を狭めて、該TD方向に19.5%緩和することにより、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Example 1>
An unstretched sheet is obtained by heating and melting the propylene-based polymer 1 at a resin temperature of 280 ° C. using a T-die film forming machine equipped with an extruder having a screw diameter of 65 mmφ and extruding it onto a cooling roll at 30 ° C. rice field. The obtained unstretched sheet was stretched 5 times in the MD direction using a stretching roll heated to 152 ° C. to obtain a uniaxially stretched film. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 8 times in the direction was obtained. The obtained biaxially stretched film was grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 165 ° C., the distance between the two rows of chucks was narrowed, and 19. A biaxially stretched film was obtained by relaxing by 5%. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<実施例2>
プロピレン系重合体1をプロピレン系重合体組成物1に変更した以外は、実施例1と同様にして、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Example 2>
A biaxially stretched film was obtained in the same manner as in Example 1 except that the propylene-based polymer 1 was changed to the propylene-based polymer composition 1. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<実施例3>
プロピレン系重合体1をプロピレン系重合体組成物2に変更した以外は、実施例1と同様にして、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Example 3>
A biaxially stretched film was obtained in the same manner as in Example 1 except that the propylene-based polymer 1 was changed to the propylene-based polymer composition 2. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<実施例4>
プロピレン系重合体3を、スクリュー径65mmφの押出機を備えたTダイ製膜機を用いて、樹脂温度250℃で加熱溶融し、30℃の冷却ロール上に押し出すことにより、未延伸シートを得た。得られた未延伸シートを、152℃に加熱した延伸ロールを用いて、MD方向に5倍に延伸することにより、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に8倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、MD方向に沿って並んだ2列のチャックで掴み、165℃に加熱した加熱炉内にて、上記2列のチャック間隔を狭めて、該TD方向に19.5%緩和することにより、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Example 4>
An unstretched sheet is obtained by heating and melting the propylene-based polymer 3 at a resin temperature of 250 ° C. using a T-die film forming machine equipped with an extruder having a screw diameter of 65 mmφ and extruding it onto a cooling roll at 30 ° C. rice field. The obtained unstretched sheet was stretched 5 times in the MD direction using a stretching roll heated to 152 ° C. to obtain a uniaxially stretched film. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 8 times in the direction was obtained. The obtained biaxially stretched film was grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 165 ° C., the distance between the two rows of chucks was narrowed, and 19. A biaxially stretched film was obtained by relaxing by 5%. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<実施例5>
プロピレン系重合体3をプロピレン系重合体4に変更した以外は、実施例4と同様にして、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Example 5>
A biaxially stretched film was obtained in the same manner as in Example 4 except that the propylene-based polymer 3 was changed to the propylene-based polymer 4. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<比較例1>
実施例1と同様にして、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に8倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、MD方向に沿って並んだ2列のチャックで掴み、165℃に加熱した加熱炉内にて、上記2列のチャック間隔を狭めて、該TD方向に6.5%緩和することにより、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Comparative example 1>
A uniaxially stretched film was obtained in the same manner as in Example 1. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 8 times in the direction was obtained. The obtained biaxially stretched film was grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 165 ° C., the distance between the two rows of chucks was narrowed, and the distance between the two rows of chucks was narrowed in the TD direction. A biaxially stretched film was obtained by relaxing by 5%. Tables 1 and 2 show the production conditions and measured values of the physical properties of the obtained biaxially stretched film.

<比較例2>
実施例1と同様にして、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に5倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、上記2列のチャック間隔を固定したままで、165℃に加熱した加熱炉内を通過させ、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Comparative example 2>
A uniaxially stretched film was obtained in the same manner as in Example 1. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 5 times in the direction was obtained. The obtained biaxially stretched film was passed through a heating furnace heated to 165 ° C. with the chuck spacing of the two rows fixed, to obtain a biaxially stretched film. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<比較例3>
プロピレン系重合体3をプロピレン系重合体5に変更した以外は、実施例1と同様にして、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に8倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、MD方向に沿って並んだ2列のチャックで掴み、165℃に加熱した加熱炉内にて、上記2列のチャック間隔を狭めて、該TD方向に13.0%緩和することにより、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Comparative example 3>
A uniaxially stretched film was obtained in the same manner as in Example 1 except that the propylene-based polymer 3 was changed to the propylene-based polymer 5. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 8 times in the direction was obtained. The obtained biaxially stretched film was grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 165 ° C., the distance between the two rows of chucks was narrowed, and 13. A biaxially stretched film was obtained by relaxing by 0%. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

<比較例4>
プロピレン系重合体6を、スクリュー径65mmφの押出機を備えたTダイ製膜機を用いて、樹脂温度260℃で加熱溶融し、30℃の冷却ロール上に押し出すことにより、未延伸シートを得た。得られた未延伸シートを、152℃に加熱した延伸ロールを用いて、MD方向に5倍に延伸することにより、一軸延伸フィルムを得た。得られた一軸延伸フィルムの両端を、MD方向に沿って並んだ2列のチャックで掴み、170℃に加熱した加熱炉内にて、上記2列のチャック間隔をTD方向に広げることにより、TD方向に8倍に延伸された二軸延伸フィルムを得た。得られた二軸延伸フィルムを、MD方向に沿って並んだ2列のチャックで掴み、165℃に加熱した加熱炉内にて、上記2列のチャック間隔を狭めて、該TD方向に19.5%緩和することにより、二軸延伸フィルムを得た。得られた二軸延伸フィルムの製造条件および物性の測定値を表1および表2に示す。
<Comparative example 4>
An unstretched sheet is obtained by heating and melting the propylene-based polymer 6 at a resin temperature of 260 ° C. using a T-die film forming machine equipped with an extruder having a screw diameter of 65 mmφ and extruding it onto a cooling roll at 30 ° C. rice field. The obtained unstretched sheet was stretched 5 times in the MD direction using a stretching roll heated to 152 ° C. to obtain a uniaxially stretched film. Both ends of the obtained uniaxially stretched film are grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 170 ° C., the distance between the two rows of chucks is widened in the TD direction to TD. A biaxially stretched film stretched 8 times in the direction was obtained. The obtained biaxially stretched film was grasped by two rows of chucks arranged along the MD direction, and in a heating furnace heated to 165 ° C., the distance between the two rows of chucks was narrowed, and 19. A biaxially stretched film was obtained by relaxing by 5%. Tables 1 and 2 show the production conditions and the measured values of the physical properties of the obtained biaxially stretched film.

表2から、実施例の二軸延伸フィルムは、比較例の二軸延伸フィルムに対して、加熱収縮率が小さく、高温下での寸法安定性に優れることがわかる。 From Table 2, it can be seen that the biaxially stretched film of the example has a smaller heat shrinkage rate and is excellent in dimensional stability at high temperatures as compared with the biaxially stretched film of the comparative example.

Figure 2021161381
Figure 2021161381

Figure 2021161381
Figure 2021161381

Claims (14)

下記要件(1)および下記要件(2)を満たすプロピレン系重合体またはプロピレン系重合体組成物を含有し、
下記要件(3)および下記要件(4)を満たす二軸延伸フィルム。
(1)温度230℃、荷重21.18Nで測定されるメルトフローレートが1g/10分〜50g/10分である。
(2)冷キシレン可溶部量が2.0質量%以下である。
(3)広角X線散乱法を用いて、二軸延伸フィルムのMD方向と直交する二軸延伸フィルムの断面にX線を入射して測定されるプロピレン系重合体のα型結晶の040面の散乱強度を、方位角に対してプロットした時の最大ピークの半値幅が13.0°以下である。
(4)下記式(I)を満たす。
0.42×E×(1−X)≦600 (I)
(式中、
Eは、温度70℃で測定される二軸延伸フィルムのTD方向の複素弾性率(MPa)を示す。
Xは、下記式(II)で算出される値を示す。)
X=14.18−12.34/D (II)
(式中、Dは、二軸延伸フィルムの密度(g/cm)を示す。)
Containing a propylene-based polymer or a propylene-based polymer composition that satisfies the following requirements (1) and the following requirements (2),
A biaxially stretched film that meets the following requirements (3) and the following requirements (4).
(1) The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 1 g / 10 minutes to 50 g / 10 minutes.
(2) The amount of the soluble part of cold xylene is 2.0% by mass or less.
(3) Using the wide-angle X-ray scattering method, the 040 plane of the α-type crystal of the propylene-based polymer measured by injecting X-rays into the cross section of the biaxially stretched film orthogonal to the MD direction of the biaxially stretched film. The half-value width of the maximum peak when the scattering intensity is plotted against the azimuth angle is 13.0 ° or less.
(4) The following formula (I) is satisfied.
0.42 x E x (1-X) ≤ 600 (I)
(During the ceremony,
E indicates the complex elastic modulus (MPa) in the TD direction of the biaxially stretched film measured at a temperature of 70 ° C.
X represents a value calculated by the following formula (II). )
X = 14.18-12.34 / D (II)
(In the formula, D indicates the density (g / cm 3 ) of the biaxially stretched film.)
前記要件(1)のメルトフローレートが1g/10分〜20g/10分である、請求項1に記載の二軸延伸フィルム。 The biaxially stretched film according to claim 1, wherein the melt flow rate of the requirement (1) is 1 g / 10 minutes to 20 g / 10 minutes. 前記要件(2)の冷キシレン可溶部量が0.1質量%〜1.0質量%である、請求項1または2に記載の二軸延伸フィルム。 The biaxially stretched film according to claim 1 or 2, wherein the amount of the cold xylene-soluble portion of the requirement (2) is 0.1% by mass to 1.0% by mass. 前記要件(3)の半値幅が6.0°〜12.0°である、請求項1〜3のいずれか一項に記載の二軸延伸フィルム。 The biaxially stretched film according to any one of claims 1 to 3, wherein the half width of the requirement (3) is 6.0 ° to 12.0 °. 前記要件(4)における前記式(I)に代えて下記式(I’)を満たす、請求項1〜4のいずれか一項に記載の二軸延伸フィルム。
300≦0.42×E×(1−X)≦500 (I’)
(式中、EおよびXは前記式(I)と同じ意味を示す。)
The biaxially stretched film according to any one of claims 1 to 4, which satisfies the following formula (I') instead of the formula (I) in the requirement (4).
300 ≤ 0.42 x E x (1-X) ≤ 500 (I')
(In the formula, E and X have the same meaning as the formula (I).)
前記要件(4)において、Eが2000MPa〜6000MPaであり、Dが0.900g/cm〜0.925g/cmである、請求項1〜5のいずれか一項に記載の二軸延伸フィルム。 In the requirement (4), E is 2000MPa~6000MPa, D is 0.900g / cm 3 ~0.925g / cm 3 , biaxially oriented film according to any one of claims 1 to 5 .. 下記プロピレン系重合体(a)と下記プロピレン系重合体(b)とを含む前記プロピレン系重合体組成物を含有する、請求項1〜6のいずれか一項に記載の二軸延伸フィルム。
プロピレン系重合体(a):温度230℃、荷重21.18Nで測定されるメルトフローレートが0.1g/10分〜15g/10分である。
プロピレン系重合体(b):温度230℃、荷重21.18Nで測定されるメルトフローレートが20g/10分〜500g/10分である。
The biaxially stretched film according to any one of claims 1 to 6, which contains the propylene-based polymer composition containing the following propylene-based polymer (a) and the following propylene-based polymer (b).
Propylene-based polymer (a): The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 0.1 g / 10 minutes to 15 g / 10 minutes.
Propylene-based polymer (b): The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 20 g / 10 minutes to 500 g / 10 minutes.
前記プロピレン系重合体(a)および前記プロピレン系重合体(b)の合計含有量に対して、
前記プロピレン系重合体(a)の含有量が50質量%〜90質量%であり、
前記プロピレン系重合体(b)の含有量が10質量%〜50質量%である、請求項7に記載の二軸延伸フィルム。
With respect to the total content of the propylene-based polymer (a) and the propylene-based polymer (b).
The content of the propylene-based polymer (a) is 50% by mass to 90% by mass.
The biaxially stretched film according to claim 7, wherein the content of the propylene-based polymer (b) is 10% by mass to 50% by mass.
厚みが10μm〜70μmである、請求項1〜8のいずれか一項に記載の二軸延伸フィルム。 The biaxially stretched film according to any one of claims 1 to 8, which has a thickness of 10 μm to 70 μm. 請求項1〜9のいずれか一項に記載の二軸延伸フィルムを含む多層フィルム。 A multilayer film containing the biaxially stretched film according to any one of claims 1 to 9. 請求項1〜9のいずれか一項に記載の二軸延伸フィルムを含む包装袋。 A packaging bag containing the biaxially stretched film according to any one of claims 1 to 9. 下記要件(1)および下記要件(2)を満たすプロピレン系重合体またはプロピレン系重合体組成物を加熱溶融して冷却ロール上に押し出すことにより未延伸シートを得る工程と、
得られた未延伸シートを、MD方向に3倍〜12倍に延伸し且つTD方向に4倍〜20倍に延伸した後、該TD方向に16%〜30%緩和することにより二軸延伸フィルムを得る工程と、
を含む、二軸延伸フィルムの製造方法。
(1)温度230℃、荷重21.18Nで測定されるメルトフローレートが1g/10分〜50g/10分である。
(2)冷キシレン可溶部量が2.0質量%以下である。
A step of obtaining an unstretched sheet by heating and melting a propylene-based polymer or a propylene-based polymer composition that satisfies the following requirements (1) and (2) and extruding it onto a cooling roll.
The obtained unstretched sheet is stretched 3 to 12 times in the MD direction and 4 to 20 times in the TD direction, and then relaxed by 16% to 30% in the TD direction to form a biaxially stretched film. And the process of getting
A method for producing a biaxially stretched film, including.
(1) The melt flow rate measured at a temperature of 230 ° C. and a load of 21.18 N is 1 g / 10 minutes to 50 g / 10 minutes.
(2) The amount of the soluble part of cold xylene is 2.0% by mass or less.
前記二軸延伸フィルムを得る工程において、
前記MD方向に3倍〜12倍に延伸することにより一軸延伸フィルムを得る工程と、
得られた一軸延伸フィルムを前記TD方向に4倍〜20倍に延伸した後、該TD方向に16%〜30%緩和することにより二軸延伸フィルムを得る工程と、
を含む、請求項12に記載の二軸延伸フィルムの製造方法。
In the step of obtaining the biaxially stretched film,
A step of obtaining a uniaxially stretched film by stretching 3 to 12 times in the MD direction, and
A step of obtaining a biaxially stretched film by stretching the obtained uniaxially stretched film 4 to 20 times in the TD direction and then relaxing 16% to 30% in the TD direction.
12. The method for producing a biaxially stretched film according to claim 12.
前記未延伸シートを得る工程で用いる冷却ロールの温度が10℃〜60℃であり、
前記一軸延伸フィルムを得る工程で用いる延伸ロールの温度が110℃〜165℃であり、
前記二軸延伸フィルムを得る工程において延伸および緩和する際の加熱温度が150℃〜200℃である、
請求項13に記載の二軸延伸フィルムの製造方法。
The temperature of the cooling roll used in the step of obtaining the unstretched sheet is 10 ° C. to 60 ° C.
The temperature of the stretching roll used in the step of obtaining the uniaxially stretched film is 110 ° C. to 165 ° C.
The heating temperature for stretching and relaxing in the step of obtaining the biaxially stretched film is 150 ° C. to 200 ° C.
The method for producing a biaxially stretched film according to claim 13.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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