JPWO2019189486A1 - Propylene resin composition, film using it and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a propylene-based film which is highly excellent in impact resistance at low temperature and heat seal strength after retort, is also excellent in rigidity and transparency, and can be suitably used as a high retort CPP. An object of the present invention is to provide a resin composition, a film and a laminate using the resin composition, and a retort pouch. SOLUTION: The propylene resin composition of the present invention contains 75 to 95% by mass of a propylene / ethylene block copolymer (A) satisfying the following requirements (a-1) to (a-4), and a specific ethylene. It contains 5 to 25% by mass of the α-olefin copolymer (B). (A-1) The MFR is 2.0 to 8.0 g / 10 minutes. (A-2) The amount of the paraxylene-soluble component is 15% by mass or more, and the amount of the para-xylene-soluble component (mass%) and the amount of the n-decane-soluble component (% by mass) have a specific relational expression (mass%). 1) is satisfied. (A-3) The content of the structural unit derived from ethylene in the paraxylene-soluble component is 20 to 30% by mass. (A-4) The pentad isotactic fraction in the paraxylene insoluble component is 94 mol% or more.

Description

The present invention relates to a propylene-based resin composition suitable for CPP use, a film and a laminate composed of the resin composition, and the use thereof. Specifically, the present invention provides a propylene-based resin composition, a film and a laminated film using the same, and a retort pouch, which have excellent impact resistance at low temperatures and are suitable for forming a CPP layer for high retort pouches that are sterilized at high temperatures. Regarding.

The retort packaging material is used for the purpose of long-term storage of the contents by filling the packaging material with the contents, sealing the contents, and then sterilizing by heating at a temperature exceeding 100 ° C. The heat sterilization treatment of the retort packaging material is roughly classified into semi-retort (treatment temperature ≤ 120 ° C.) and high retort (treatment temperature> 120 ° C.) according to the temperature.

The retort packaging material is usually composed of a surface protection / printing layer (polyethylene terephthalate (PET) film, etc.), a barrier layer (aluminum foil, etc.), and a heat seal layer (polyethylene film, etc.) bonded together via an adhesive. Since the heat seal layer is inside the bag, it is in contact with the contents.

Conventionally, a polyolefin film having excellent heat-sealing properties has been used for the heat-sealing layer of the retort packaging material. As a packaging material compatible with semi-retort, polyethylene-based resins such as LLDPE and HDPE, which have a relatively high density, and polypropylene-based resins having improved impact resistance by blending an elastomer component or the like with random PP are used.

On the other hand, high retort-compatible packaging materials lack heat resistance with the above materials, so a composition in which a propylene-ethylene copolymer (so-called block PP) is further mixed with an elastomer component is used, and a CPP film is used. (Polypropylene-based non-stretched film) has been preferably used.

Recently, in order to support microwave oven heating, a transparent type retort pouch using a barrier base material such as inorganic vapor-deposited PET has come to be used instead of using an aluminum foil for the barrier layer.

For this reason, the heat seal layer can withstand the heat seal strength required to protect the contents during heat sterilization and storage, sufficient impact resistance to withstand the dropping of the bag filled with the contents, and heat sterilization treatment. Heat resistance and low odor that does not impair the flavor of the contents are required. Further, in the transparent type retopouch, the CPP film to be the sealant layer is also required to have excellent transparency.

Various resin compositions used as materials for CPP films have been proposed so far. For example, Patent Documents 1 to 9 include specific propylene / ethylene copolymers and ethylene / α-olefin copolymers. A resin composition containing the above, or a resin composition containing a hydrogenated styrene-based thermoplastic elastomer, polyethylene, or the like has been proposed. As a result, CPP films having heat-sealing properties, suppression of citron skin phenomenon, and low-temperature impact resistance are taught.

High retort CPP using block PP has excellent heat resistance and relatively excellent impact resistance, but has a matrix / domain structure of polypropylene homopolymer part and ethylene / propylene rubber / polyethylene part. Therefore, transparency may be insufficient. Further, the impact resistance is not always satisfactory with a large pouch having a large content, and an elastomer component (low density ethylene / α-olefin copolymer or the like) is added.

Further, since the addition of the elastomer component may cause problems such as a decrease in heat seal strength, a decrease in rigidity, and a decrease in blocking resistance after retort sterilization, a CPP film for high retort having excellent these characteristics is desired.

That is, it has been desired to develop a CPP film that is more excellent in impact resistance at low temperature and heat seal strength after retort sterilization, and also has excellent rigidity and transparency, and is suitable for high retort use.

The present inventor has added a specific amount of an ethylene / α-olefin copolymer having a specific composition to a propylene / ethylene block copolymer having a specific composition to provide impact resistance at a low temperature and heat after retorting. The present invention has been completed by finding that a high-ethylene CPP film having excellent sealing strength, rigidity, and transparency can be obtained.

JP 2015-168766 WO2017 / 38349 Pamphlet Japanese Unexamined Patent Publication No. 2012-172124 Japanese Unexamined Patent Publication No. 2006-104279 JP-A-2010-150318 Japanese Unexamined Patent Publication No. 2000-256532 Japanese Unexamined Patent Publication No. 2003-183462 Japanese Unexamined Patent Publication No. 2003-96251 Japanese Unexamined Patent Publication No. 2001-288330

The present invention is a propylene-based resin composition capable of producing a film that is highly excellent in impact resistance at low temperature and heat seal strength after retort, is also excellent in rigidity and transparency, and can be suitably used as a high retort CPP. , A film and a laminate using the same, and a retort pouch.

As a result of diligent studies to achieve the above problems, the present inventor has found that a resin composition containing a propylene / ethylene block copolymer exhibiting specific properties and an ethylene / α-olefin copolymer is a high retort CPP. We have found that it is particularly excellent as a film raw material for a film, and have completed the present invention.

That is, the gist of the present invention relates to the following items [1] to [7].
[1] 75 to 95% by mass of the propylene / ethylene block copolymer (A) satisfying the following requirements (a-1) to (a-4).
A propylene resin composition containing 5 to 25% by mass of an ethylene / α-olefin copolymer (B) satisfying the following requirements (b-1) and (b-2).
(A-1) The melt flow rate (230 ° C., 2.16 kg load) is 2.0 to 8.0 g / 10 minutes.
(A-2) The amount of the paraxylene-soluble component is 15% by mass or more, and the amount of the para-xylene-soluble component (mass%) and the amount of the n-decane-soluble component (% by mass) are the following relational expressions. Satisfy (1).

Amount of n-decane soluble component ≤ Paraxylene soluble component amount × 0.95… (1)
(A-3) The content of the structural unit derived from ethylene in the paraxylene-soluble component is 20 to 30% by mass.
(A-4) The pentad isotactic fraction (mmmm fraction) in the paraxylene insoluble component is 94 mol% or more.
(B-1) The melt flow rate (190 ° C., 2.16 kg load) is 0.5 to 5.0 g / 10 minutes.
(B-2) a density of ^{890kg / m 3 ~910kg / m 3} .
[2] The propylene-based resin composition according to the above [1], wherein the ethylene / α-olefin copolymer (B) further satisfies the requirement (b-3).
(B-3) The density X (kg / m ³ ) and the amount of n-decane-soluble component Y (mass%) satisfy the following relational expression (2).

^{Y ≦ 0.0046X 2 -8.578X + 4000 ...} (2)
[3] A film comprising the propylene-based resin composition according to the above [1] or [2].
[4] The film according to the above [3], which is a non-stretched film.
[5] A laminated film having a layer made of the propylene-based resin composition according to the above [1] or [2].
[6] The laminated film according to the above [5], wherein the layer made of the propylene resin composition according to the above [1] or [2] is provided as a surface layer on one surface.
[7] A retort pouch made of the laminated film according to the above [6].

The propylene-based resin composition of the present invention is suitable for producing films such as high-retort CPP films, and is also excellent in blocking resistance. The film obtained from the propylene-based resin composition of the present invention has excellent heat-sealing properties, high heat-sealing strength, is suitable as an inner layer surface of a retort pouch, has excellent impact resistance at low temperatures, and is a high-retort CPP film. It is also excellent in transparency and rigidity as well as excellent quality. Since the laminate of the present invention and the retort pouch made of the laminate are excellent in blocking resistance, they are excellent in handleability at the time of filling the contents, high heat seal strength, and excellent heat seal strength after retort sterilization treatment.

Hereinafter, the present invention will be specifically described.
<Propene resin composition>
The propylene-based resin composition of the present invention contains a specific propylene / ethylene block copolymer (A) and an ethylene / α-olefin copolymer (B) as essential components.
Propylene / ethylene block copolymer (A)
The propylene / ethylene block copolymer (A) used in the present invention satisfies the following requirements (a-1) to (a-4). The polymerization catalyst and polymerization conditions used in the production of the propylene / ethylene block copolymer (A) according to the present invention are not particularly limited as long as the following requirements (a-1) to (a-4) are satisfied. Further, the propylene / ethylene block copolymer (A) according to the present invention may be used alone or in combination of two or more. When two or more types are used in combination, the combined propylene / ethylene block copolymer as a whole satisfies the following requirements (a-1) to (a-4).
(A-1) The melt flow rate (MFR) is 2.0 to 8.0 g / 10 minutes. This MFR is a value measured at 230 ° C. under a load of 2.16 kg according to ASTM D-1238, preferably 2.5 to 6.0 g / 10 minutes, and more preferably 3.0 to 5.0 g. / 10 minutes.
(A-2) The amount of the paraxylene-soluble component is 15% by mass or more, and the amount of the para-xylene-soluble component (mass%) and the amount of the n-decane-soluble component (% by mass) are the following relational expressions. Satisfy (1).

Amount of n-decane soluble component ≤ Paraxylene soluble component amount × 0.95… (1)
The amount of the paraxylene-soluble component of the propylene / ethylene block copolymer (A) is preferably 15 to 30% by mass, more preferably 20 to 30% by mass. Further, the following relational expression (1') is preferably satisfied, and more preferably the following relational expression (1 ″) is satisfied.

Amount of n-decane soluble component ≤ Paraxylene soluble component amount x 0.90 ... (1')
0.80 ≤ n-decane-soluble component amount ≤ para-xylene-soluble component amount x 0.90 ... (1'')
(A-3) The content of the structural unit derived from ethylene in the paraxylene-soluble component is 20 to 30% by mass. The content of the structural unit derived from ethylene in the paraxylene-soluble component is preferably 20 to 28% by mass, and more preferably 22 to 28% by mass.
(A-4) The pentad isotactic fraction (mmmm fraction) in the paraxylene insoluble component is 94 mol% or more. The pentad isotactic fraction in the paraxylene insoluble component is preferably 94.5 mol% or more, more preferably 95.0 mol% or more.

In the present invention, the amount of the paraxylene-soluble component, the amount of the para-xylene-insoluble component, and the amount of the n-decane-soluble component are ratios (mass%) determined by the test method described later.

The propylene / ethylene block copolymer (A) used in the present invention is usually a block copolymer having a propylene homopolymer part and a propylene / ethylene random copolymer part or an ethylene polymer part. In the propylene / ethylene block copolymer (A) having a propylene homopolymer part and a propylene / ethylene random copolymer part, the propylene / ethylene random copolymer part is mainly a paraxylene-soluble component and an n-decane. It becomes a soluble component, and the propylene copolymer part mainly becomes a paraxylene insoluble component and an n-decane insoluble component. Here, since n-decane is a poorer solvent for para-xylene and n-decane, the portion of the copolymer having some crystallinity is dissolved in para-xylene and n-decane. It is considered that there is a difference that it becomes insoluble in.

In the present invention, the proportion of the propylene / ethylene random copolymer portion is relatively high, and the ethylene content of the propylene / ethylene random copolymer portion is relatively low as compared with the conventional general-purpose propylene / ethylene block copolymer. A propylene-ethylene block copolymer (A) in which the homopolymer portion exhibits high stereoregularity and the amount of the paraxylene-soluble component and the amount of the n-decane-soluble component are different from each other is used as a propylene resin composition. By using the main component, the film obtained from the resin composition exhibits properties particularly suitable for applications of high-retort CPP films.

That is, the propylene / ethylene block copolymer (A) according to the present invention satisfies the above requirements (a-1) to (a-4), whereby the copolymer (A) and the ethylene obtained later will be obtained. -A resin composition containing α-olefin copolymer (B) in a specific amount ratio is suitable for forming a film such as a high retort CPP film, and the obtained film has heat-sealing characteristics and resistance to low temperatures. Properties such as impact resistance, heat seal strength after retort, rigidity, and transparency can be achieved.
-Method for producing the propylene / ethylene block copolymer (A) The propylene / ethylene block copolymer (A) according to the present invention is not limited in its production method as described above, and may be a polymerization catalyst used at the time of production. The polymerization conditions are not particularly limited, but in the presence of an olefin stereoregular catalyst such as a Cheegler-Natta catalyst or a metallocene catalyst, the copolymer part of propylene or a small amount of propylene and a small amount of ethylene can be used in the first polymerization step. After producing the propylene / ethylene random copolymer portion, the propylene / ethylene copolymer elastomer portion is obtained by copolymerizing propylene and a larger amount of ethylene than in the first step in the second polymerization step.

In the production of the propylene / ethylene block copolymer (A) according to the present invention, for example, the solid titanium catalyst component (I) and the organic metal compound catalyst component (II) described below are required as the polymerization catalyst. Propylene is further polymerized using an olefin polymerization catalyst containing an electron donor according to the above conditions, and propylene and ethylene are further copolymerized to satisfy the above requirements (a-1) to (a-4). The propylene / ethylene block copolymer (A) to be satisfied can be preferably produced.

[Solid titanium catalyst component (I)]
The solid titanium catalyst component (I) constituting the catalyst for olefin polymerization contains, for example, titanium, magnesium, halogen and, if necessary, an electron donor. A known component can be used without limitation for the solid titanium catalyst component (I).

A magnesium compound and a titanium compound are usually used for the preparation of the solid titanium catalyst component (I).

Specific examples of magnesium compounds include magnesium halides such as magnesium chloride and magnesium bromide; alkoxymagnesium halides such as methoxymagnesium chloride, ethoxymagnesium ethoxychloride and magnesium phenoxychloride; ethoxymagnesium, isopropoxymagnesium, butoxymagnesium and 2-ethyl. Examples thereof include alkoxymagnesium such as hexoxymagnesium; allyloxymagnesium such as phenoxymagnesium; and carboxylate of magnesium such as magnesium stearate; One type of magnesium compound may be used alone, or two or more types may be used in combination. Further, the magnesium compound may be a complex compound with another metal, a compound compound or a mixture with another metal compound.

Among them, a magnesium compound containing a halogen is preferable, and magnesium halide, particularly magnesium chloride, is more preferable. In addition, alkoxymagnesium such as ethoxymagnesium is also preferable. Further, the magnesium compound may be a compound derived from another substance, for example, a compound obtained by contacting an organic magnesium compound such as a Grignard reagent with titanium halide, silicon halide, alcohol halide or the like.

Examples of the titanium compound include a tetravalent titanium compound represented by the following formula.

Ti (OR) _g X _4-g
(In the formula, R is a hydrocarbon group, X is a halogen atom, and g is 0 ≦ g ≦ 4.)
Specific examples of the titanium compounds, TiCl _4, titanium tetrahalides of TiBr _{4 such; Ti (OCH 3) Cl 3} , Ti (OC 2 H 5) Cl 3, Ti (O-n-C 4 H 9) Cl ₃ , Ti (OC ₂ H ₅ ) Br ₃ , Ti (O-i-C ₄ H ₉ ) Br _{3 and} other trihalogenated alkoxytitanium; Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Dihalogenated alkoxytitanium such as Cl ₂ ; Monohalogenated alkoxytitanium such as Ti (OCH ₃ ) ₃ Cl, Ti (On-C ₄ H ₉ ) ₃ Cl, Ti (OC ₂ H ₅ ) ₃ Br; Ti ( Tetraalkoxytitanium such as OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (O-2-ethylhexyl) _{4 and the} like. One type of titanium compound may be used alone, or two or more types may be used in combination. Of these, titanium tetrahalogenate is preferable, and titanium tetrachloride is more preferable.

As the magnesium compound and the titanium compound, for example, compounds described in detail in JP-A-57-63310 and JP-A-5-170843 can also be used.

Specific examples of a preferable method for preparing the solid titanium catalyst component (I) used in producing the propylene / ethylene block copolymer (A) according to the present invention include the following (P-1) to (P-). The method of 4) can be mentioned.
(P-1) A solid adduct composed of an electron donor component (1) such as a magnesium compound and an alcohol, an electron donor component (2) described later, and a titanium compound in a liquid state are used as an inert hydrocarbon solvent. A method of contacting in a suspended state in coexistence.
(P-2) A method in which a solid adduct composed of a magnesium compound and an electron donor component (1), an electron donor component (2), and a titanium compound in a liquid state are brought into contact with each other in a plurality of times.
(P-3) A solid adduct composed of a magnesium compound and an electron donor component (1), an electron donor component (2), and a liquid titanium compound are suspended in the presence of an inert hydrocarbon solvent. A method of contacting in a state and contacting in multiple times.
(P-4) A method in which a liquid magnesium compound composed of a magnesium compound and an electron donor component (1), a liquid titanium compound, and an electron donor component (2) are brought into contact with each other.

The reaction temperature at the time of preparing the solid titanium catalyst component (I) is preferably in the range of -30 to 150 ° C. Specifically, for example, the magnesium compound and the titanium compound are brought into contact with each other at a temperature of 120 to 150 ° C. in the presence of an electron donating compound and, if necessary, a silicon compound, and then at a temperature of 100 to 150 ° C. It can be prepared by washing with an inert solvent.

The solid titanium catalyst component (I) can also be prepared, if necessary, in the presence of a known medium. Specific examples of the medium include aromatic hydrocarbons such as toluene having a slight polarity, known aliphatic hydrocarbons such as heptane, octane, decane, and cyclohexane, or alicyclic hydrocarbon compounds. Of these, aliphatic hydrocarbons are preferable.

As the electron donor component (1) used for forming a solid adduct or a liquid magnesium compound, a known compound capable of solubilizing the magnesium compound in a temperature range of about room temperature to 300 ° C. is preferable, and for example, alcohol or aldehyde. , Amines, carboxylic acids and mixtures thereof and the like are preferred. Examples of these compounds include the compounds described in JP-A-57-63310 and JP-A-5-170843.

Specific examples of alcohols capable of solubilizing magnesium compounds include methanol, ethanol, propanol, butanol, isobutanol, ethylene glycol, 2-methylpentanol, 2-ethylbutanol, n-heptanol, n-octanol, and 2-ethylhexanol. , Decanol, dodecanol and other aliphatic alcohols; cyclohexanol, methylcyclohexanol and other alicyclic alcohols; benzyl alcohol, methylbenzyl alcohol and other aromatic alcohols; n-butylcellsolve and other aliphatic alcohols having an alkoxy group; And so on.

Specific examples of the carboxylic acid include organic carboxylic acids having 7 or more carbon atoms such as caprylic acid and 2-ethylhexanoic acid. Specific examples of aldehydes include aldehydes having 7 or more carbon atoms such as capric aldehyde and 2-ethylhexyl aldehyde. Specific examples of amines include amines having 6 or more carbon atoms such as heptyl amine, octyl amine, nonyl amine, lauryl amine, and 2-ethylhexyl amine.

As the electron donor component (1), the above alcohols are preferable, and ethanol, propanol, butanol, isobutanol, hexanol, 2-ethylhexanol, and decanol are particularly preferable.

The composition ratio of the magnesium of the obtained solid adduct or the magnesium compound in the liquid state and the electron donor component (1) varies depending on the type of the compound used, and therefore cannot be unconditionally specified, but can be defined as 1 mol of magnesium in the magnesium compound. On the other hand, the electron donor component (1) is preferably 2 mol or more, more preferably 2.3 mol or more, and particularly preferably 2.7 mol or more and 5 mol or less.

A particularly preferred example of the electron donor used as required for the solid titanium catalyst component (I) is an aromatic carboxylic acid ester and / or a compound having two or more ether bonds via a plurality of carbon atoms ( Hereinafter, “electron donor component (2)”) may be mentioned.

As the electron donor component (2), known aromatic carboxylic acid esters and polyether compounds that are conventionally preferably used as catalysts for olefin polymerization, for example, JP-A-5-170843 and JP-A-2001-354714. The compounds described in the above can be used without limitation.

Specific examples of the aromatic carboxylic acid ester include aromatic carboxylic acid monoesters such as benzoic acid ester and toluic acid ester, and aromatic polyvalent carboxylic acid ester such as phthalates. Among them, aromatic polyvalent carboxylic acid esters are preferable, and phthalates are more preferable. As the phthalates, alkyl phthalates such as ethyl phthalate, n-butyl phthalate, isobutyl phthalate, hexyl phthalate, and heptyl phthalate are preferable, and diisobutyl phthalate is particularly preferable.

Specific examples of the polyether compound include compounds represented by the following structural formulas.

上記式中、ｍは１≦ｍ≦１０の整数、より好ましくは３≦ｍ≦１０の整数であり、Ｒ¹¹〜Ｒ³⁶は、それぞれ独立に、水素原子、あるいは炭素、水素、酸素、フッ素、塩素、臭素、ヨウ素、窒素、硫黄、リン、ホウ素及びケイ素から選択される少なくとも１種の元素を有する置換基である。ｍが２以上である場合、複数個存在するＲ¹¹及びＲ¹²は、それぞれ同じであっても異なっていてもよい。任意のＲ¹¹〜Ｒ³⁶、好ましくはＲ¹¹及びＲ¹²は共同してベンゼン環以外の環を形成していてもよい。

In the above formula, m is an integer of 1 ≦ m ≦ 10, more preferably an integer of 3 ≦ m ≦ 10, and R ^{11 to} R ³⁶ are independently hydrogen atoms or carbon, hydrogen, oxygen, fluorine, and so on. It is a substituent having at least one element selected from chlorine, bromine, iodine, nitrogen, sulfur, phosphorus, boron and silicon. When m is 2 or more, a plurality of R ¹¹ and R ¹² may be the same or different. Any R ^{11 to} R ³⁶ , preferably R ¹¹ and R ^12, may jointly form a ring other than the benzene ring.

Specific examples of such compounds include mono-substituted dialkoxys such as 2-isopropyl-1,3-dimethoxypropane, 2-s-butyl-1,3-dimethoxypropane, and 2-cumyl-1,3-dimethoxypropane. Propanes; 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2-methyl-2-isopropyl-1,3-dimethoxypropane, 2-methyl- 2-Cyclohexyl-1,3-dimethoxypropane, 2-methyl-2-isobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-bis (cyclohexylmethyl) -1 , 3-Dimethoxypropane, 2,2-diisobutyl-1,3-diethoxypropane, 2,2-diisobutyl-1,3-dibutoxypropane, 2,2-di-s-butyl-1,3-dimethoxypropane Di-substituted dialkoxys such as 2,2-dineopentyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 2-cyclohexyl-2-cyclohexylmethyl-1,3-dimethoxypropane Propanes; 2,3-dicyclohexyl-1,4-diethoxybutane, 2,3-dicyclohexyl-1,4-diethoxybutane, 2,3-diisopropyl-1,4-diethoxybutane, 2,4-diphenyl -1,5-dimethoxypentane, 2,5-diphenyl-1,5-dimethoxyhexane, 2,4-diisopropyl-1,5-dimethoxypentane, 2,4-diisobutyl-1,5-dimethoxypentane, 2,4 -Dialkoxyalkanes such as diisoamyl-1,5-dimethoxypentane; 2-methyl-2-methoxymethyl-1,3-dimethoxypropane, 2-cyclohexyl-2-ethoxymethyl-1,3-diethoxypropane, 2 -Trialkoxyalkanes such as cyclohexyl-2-methoxymethyl-1,3-dimethoxypropane; and the like. One type of polyether compound may be used alone, or two or more types may be used in combination. Of these, 1,3-diethers are preferable, and in particular, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane and 2-isopropyl-2-isopentyl-1 are preferable. , 3-Dimethoxypropane, 2,2-dicyclohexyl-1,3-dimethoxypropane, 2,2-bis (cyclohexylmethyl) 1,3-dimethoxypropane are preferred.

In the solid titanium catalyst component (I), the halogen / titanium (atomic ratio) (that is, the number of moles of halogen atoms / the number of moles of titanium atoms) is 2 to 100, preferably 4 to 90, and is an electron donor component. The (1) / titanium atom (molar ratio) is 0 to 100, preferably 0 to 10, and the electron donor component (2) / titanium atom (molar ratio) is 0 to 100, preferably 0 to 10. The magnesium / titanium (atomic ratio) (ie, the number of moles of magnesium atoms / the number of moles of titanium atoms) is 2 to 100, preferably 4 to 50.

The solid titanium catalyst component (I) may be supported on an organic carrier or an inorganic carrier, and as the carrier, an inorganic porous powder such as silica is preferably used.

As a more detailed preparation condition for the solid titanium catalyst component (I), for example, the conditions described in EP585869A1 and JP-A-5-170843 are preferably used except that the electron donor component (2) is used. Can be done.

[Organometallic compound catalyst component (II)]
The organometallic compound catalyst component (II) is a component containing a metal element selected from Group 1, Group 2, and Group 13 of the periodic table. For example, a compound containing a Group 13 metal (organometallic compound or the like), a complex alkylated product of a Group 1 metal and aluminum, an organometallic compound of a Group 2 metal, or the like can be used. Of these, organoaluminum compounds are preferable.

Specifically, as the organometallic compound catalyst component (II), the organometallic compound catalyst component described in a known document such as EP585869A1 can be preferably used.

In the production of the propylene / ethylene block copolymer (A) according to the present invention, together with the above-mentioned solid titanium catalyst component (I) and the organometallic compound catalyst component (II), the above-mentioned electrons are not impaired. In addition to the donor component (1) and the electron donor component (2), a known electron donor component (3) can be combined and used for prepolymerization and / or main polymerization.

As the electron donor component (3), an organosilicon compound is preferable. This organosilicon compound is, for example, a compound represented by the following formula.

R _n Si (OR') _4-n
(In the formula, R and R'are hydrocarbon groups, and n is an integer of 0 <n <4.)
Specific examples of the organosilicon compound represented by the above formula include diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, dicyclohexyldimethoxysilane, and cyclohexylmethyldimethoxysilane. , Cyclohexylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, cyclohexyltrimethoxysilane, cyclopentyltrimethoxysilane, 2-methylcyclopentyltrimethoxysilane , Cyclopentyltriethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, tricyclopentylmethoxysilane, dicyclopentylmethylmethoxysilane, dicyclopentylethylmethoxysilane, cyclopentyldimethylethoxysilane and the like are used. Of these, vinyltriethoxysilane, diphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, and dicyclopentyldimethoxysilane are preferable.

Further, the silane compound represented by the following formula described in International Publication No. 2004/016662 pamphlet is also a preferable example of the organosilicon compound.

Si (OR ^a ) ₃ (NR ^b R ^c )
In the above formula, ^Ra is a hydrocarbon group having 1 to 6 carbon atoms. For example, it is an unsaturated or saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms, and a hydrocarbon group having 2 to 6 carbon atoms is particularly preferable. Specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, n-pentyl group, iso-pentyl group, cyclopentyl group, n. -Hexyl group, cyclohexyl group and the like can be mentioned. Of these, the ethyl group is particularly preferable.

R ^b is a hydrocarbon group having 1 to 12 carbon atoms or hydrogen. For example, an unsaturated or saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms or hydrogen. Specific examples include hydrogen atom, methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, n-pentyl group, iso-pentyl group and cyclopentyl. Examples include a group, an n-hexyl group, a cyclohexyl group, an octyl group and the like. Of these, the ethyl group is particularly preferable.

R ^c is a hydrocarbon group having 1 to 12 carbon atoms. For example, it is an unsaturated or saturated aliphatic hydrocarbon group having 1 to 12 carbon atoms. Specific examples include methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl group, n-pentyl group, iso-pentyl group, cyclopentyl group, n. -Hexyl group, cyclohexyl group, octyl group and the like can be mentioned. Of these, the ethyl group is particularly preferable.

Specific examples of the organosilicon compound represented by the above formula include dimethylaminotriethoxysilane, diethylaminotriethoxysilane, diethylaminotrimethoxysilane, diethylaminotri n-propoxysilane, din-propylaminotriethoxysilane, and methyl n-. Examples thereof include propylaminotriethoxysilane, t-butylaminotriethoxysilane, ethyl n-propylaminotriethoxysilane, ethyliso-propylaminotriethoxysilane, and methylethylaminotriethoxysilane.

Further, as another example of the organosilicon compound, a compound represented by the following formula can be mentioned.

RNSi (OR ^a ) ₃
In the above formula, RN is a cyclic amino group. Specific examples include a perhydroquinolino group, a perhydroisoquinolino group, a 1,2,3,4-tetrahydroquinolino group, a 1,2,3,4-tetrahydroisoquinolino group, an octamethyleneimino group, and the like. Can be mentioned. ^Ra is the same as above.

Specific examples of the organosilicon compound represented by the above formula include (perhydroquinolino) triethoxysilane, (perhydroisoquinolino) triethoxysilane, and (1,2,3,4-tetrahydroquinolino) triethoxy. Examples thereof include silane, (1,2,3,4-tetrahydroisoquinolino) triethoxysilane, octamethyleneiminotriethoxysilane and the like.

Each of the organosilicon compounds described above may be used in combination of two or more.

Specifically, as the mode of the catalyst used in the production of the propylene / ethylene block copolymer (A) according to the present invention, in addition to the modes described in the above-mentioned documents, for example, JP-A-2000-219787, Examples thereof include aspects described in JP-A-2-84404 and JP-A-2002-30128.

[polymerization]
The propylene / ethylene block copolymer (A) according to the present invention is prepolymerized obtained by polymerizing propylene in the presence of the above-mentioned olefin polymerization catalyst, and then copolymerizing or prepolymerizing propylene and ethylene. It can be produced by a method such as polymerizing propylene in the presence of a catalyst and then copolymerizing propylene and ethylene.

The propylene / ethylene block copolymer (A) according to the present invention is more preferably produced in the presence of a prepolymerization catalyst.

The prepolymerization is carried out by prepolymerizing the olefin in an amount of usually 0.1 to 1000 g, preferably 0.3 to 500 g, particularly preferably 1 to 200 g per 1 g of the olefin polymerization catalyst. In the prepolymerization, a catalyst having a concentration higher than the catalyst concentration in the system in the main polymerization can be used.

The concentration of the solid titanium catalyst component (I) in the prepolymerization is usually 0.001 to 200 mmol, preferably 0.01 to 50 mmol, more preferably 0.1 to 1 in terms of titanium atoms per liter of the liquid medium. It is 20 mmol.

The amount of the organic metal compound catalyst component (II) in the prepolymerization is such that an amount of usually 0.1 to 1000 g, preferably 0.3 to 500 g of a polymer is produced per 1 g of the solid titanium catalyst component (I). It may be sufficient, and is usually 0.1 to 300 mol, preferably 0.5 to 100 mol, and more preferably 1 to 50 mol, per 1 mol of titanium atoms in the solid titanium catalyst component (I).

In the prepolymerization, the electron donor components can be used if necessary, and these components are usually 0.1 to 50 mol per 1 mol of titanium atoms in the solid titanium catalyst component (I). It is preferably 0.5 to 30 mol, more preferably 1 to 10 mol.

Prepolymerization can be carried out under mild conditions by adding an olefin and the above-mentioned catalyst component to an inert hydrocarbon medium. When an inert hydrocarbon medium is used, the prepolymerization is preferably carried out in batch.

Specific examples of the inert hydrocarbon medium include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane and kerosene; cyclopentane, methylcyclopentane, cyclohexane, cycloheptane and methylcycloheptane. , Aliphatic hydrocarbons such as cyclooctane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; or mixtures thereof. Of these, aliphatic hydrocarbons are preferable.

Prepolymerization can also be carried out using the olefin itself as a solvent. It can also be prepolymerized in a substantially solvent-free state. In this case, it is preferable to carry out the prepolymerization continuously.

The olefin used in the prepolymerization may be the same as or different from the olefin used in the main polymerization described later. As the olefin, propylene is particularly preferable.

The temperature at the time of prepolymerization is usually -20 to 100 ° C, preferably -20 to 80 ° C, and more preferably 0 to 40 ° C.

Next, the main polymerization carried out after or without passing through the prepolymerization will be described.

This polymerization is divided into a step of producing a propylene homopolymer component and a step of producing a propylene-ethylene copolymer component.

The main polymerization (and prepolymerization) can be carried out by any of a liquid phase polymerization method such as bulk polymerization method, dissolution polymerization and suspension polymerization, or a vapor phase polymerization method. As a step for producing the propylene homopolymer component, a liquid phase polymerization method such as bulk polymerization or suspension polymerization or a gas phase polymerization method is preferable. As a step for producing the propylene-ethylene copolymer component, a liquid phase polymerization method such as bulk polymerization or suspension polymerization or a gas phase polymerization method is preferable, and a gas phase polymerization method is more preferable.

When the main polymerization takes the reaction form of slurry polymerization, the above-mentioned inert hydrocarbon used in the prepolymerization can be used as the reaction solvent, or an olefin that is liquid at the reaction temperature and pressure can be used.

In the present polymerization, the solid titanium catalyst component (I) is usually in an amount of 0.0001 to 0.5 mmol, preferably 0.005 to 0.1 mmol in terms of titanium atoms per liter of polymerization volume. Used. The organometallic compound catalyst component (II) is usually used in an amount of 1 to 2000 mol, preferably 5 to 500 mol, based on 1 mol of titanium atoms in the prepolymerization catalyst component in the polymerization system. When the electron donor component is used, it is usually 0.001 to 50 mol, preferably 0.01 to 30 mol, more preferably 0.05 to 20 mol, relative to 1 mol of the organometallic compound catalyst component (II). Used in molar amounts.

When this polymerization is carried out in the presence of hydrogen, the molecular weight of the obtained polymer can be adjusted (lowered), and a polymer having a large melt flow rate (MFR) can be obtained. The amount of hydrogen required to adjust the molecular weight varies depending on the type of manufacturing process used, the polymerization temperature, and the pressure, and may be appropriately adjusted.

In the step of producing the propylene homopolymer component, the polymerization temperature and the amount of hydrogen can be adjusted to adjust the MFR. Further, also in the step of producing the propylene-ethylene copolymer component, the ultimate viscosity can be adjusted by adjusting the polymerization temperature, pressure, and amount of hydrogen.

In the main polymerization, the polymerization temperature of the olefin is usually 0 to 200 ° C., preferably 30 to 100 ° C., and more preferably 50 to 90 ° C. The pressure (gauge pressure) is usually normal pressure to 100 kgf / cm ² (9.8 MPa), preferably ^{2 to} 50 kgf / cm 2 (0.20 to 4.9 MPa).

In the production of the propylene / ethylene block copolymer (A), the polymerization can be carried out by any of a batch type, a semi-continuous type and a continuous type. Further, the shape of the reactor can be either a tubular type or a tank type. Further, the polymerization can be carried out in two or more stages by changing the reaction conditions. In this case, a tubular type and a tank type can be combined.

In order to obtain the propylene / ethylene copolymer portion (A) in the propylene / ethylene block copolymer, the ethylene / (ethylene + propylene) gas ratio is controlled in the polymerization step 2 described later. The ethylene / (ethylene + propylene) gas ratio is usually 5 to 80 mol%, preferably 10 to 70 mol%, more preferably 15 to 60 mol%.

The n-decane insoluble component and the paraxylene insoluble component of the propylene / ethylene block copolymer (A) are mainly composed of a propylene homopolymer component. On the other hand, the n-decane-soluble component and the para-xylene-soluble component are mainly composed of an ethylene / propylene copolymer component which is a rubber-like component. For example, the propylene / ethylene block copolymer (A) can be obtained by continuously carrying out the following two polymerization steps 1 and 2.

(Polymerization step 1)
A step of polymerizing propylene in the presence of a solid titanium catalyst component to produce a propylene homopolymer component (propylene homopolymer production step).

(Polymerization step 2)
A step of copolymerizing propylene and ethylene in the presence of a solid titanium catalyst component to produce an ethylene / propylene copolymer component (copolymer rubber manufacturing process).

In particular, it is more preferable that the polymerization step 1 is performed in the first stage and the polymerization step 2 is performed in the second stage. Each polymerization step 1 and 2 can also be carried out using two or more polymerization tanks. The contents of the n-decane-soluble component and the para-xylene-soluble component of the propylene / ethylene block copolymer (A) can be adjusted by the polymerization time (residence time) of the polymerization step 1 and the polymerization step 2. Further, the polymerization step 1 in the previous stage may be performed by a polymerizer having two or more stages in series. In that case, the ratio of propylene to hydrogen in each stage may be different for each polymerizer.
Ethylene / α-olefin copolymer (B)
The ethylene / α-olefin copolymer (B) used in the present invention satisfies the following requirements (b-1) and (b-2). As long as the ethylene / α-olefin copolymer (B) according to the present invention satisfies the following requirements (b-1) and (b-2), the polymerization catalyst and polymerization conditions used in the production thereof are not particularly limited. Further, the ethylene / α-olefin copolymer (B) according to the present invention may be used alone or in combination of two or more. When two or more kinds are used in combination, the combined ethylene / α-olefin copolymer as a whole satisfies the following requirements (b-1) and (b-2).
(B-1) The melt flow rate (MFR) is 0.5 to 5.0 g / 10 minutes. This melt flow rate is a value measured at 190 ° C. under a load of 2.16 kg according to ASTM D-1238, preferably 0.5 to 4.0 g / 10 minutes, and more preferably 1.0 to 3. It is 0.0 g / 10 minutes.
(B-2) a density of ^{890kg / m 3 ~910kg / m 3} . This density is preferably in the range of ^{890 to 905 kg / m 3} , more preferably 895 to 905 kg / m ^3.

The ethylene / α-olefin copolymer (B) according to the present invention can be obtained together with the above-mentioned propylene / ethylene block copolymer (A) by satisfying the above requirements (b-1) and (b-2). A film made of a resin composition has excellent heat resistance and transparency, and exhibits properties particularly suitable for applications of high-retort CPP films.

The ethylene / α-olefin copolymer (B) according to the present invention preferably further satisfies the following requirement (b-3) in addition to the above requirements (b-1) and (b-2).
(B-3) The density X (kg / m ³ ) and the amount of n-decane-soluble component Y (mass%) satisfy the following relational expression (2).

^{Y ≦ 0.0046X 2 -8.578X + 4000 ...} (2)
More preferably, the density X (kg / m ³ ) and the amount of n-decane-soluble component Y (mass%) satisfy the following relational expression (2').

^{Y ≦ 0.00465X 2 -8.625X + 4000 ...} (2 ')
^{When the density (kg / m 3} ) and the amount of n-decane-soluble component Y (mass%) of the ethylene / α-olefin copolymer (B) satisfy the above relationship, it is preferable because the blocking resistance is excellent. ..

The ethylene / α-olefin copolymer (B) according to the present invention is obtained by copolymerizing ethylene and an α-olefin in the presence of a copolymerization catalyst. As the α-olefin, α-olefin having 3 to 20 carbon atoms, preferably propylene, 1-butene, 2-methyl-1-propene, 2-methyl-1-butene, 3-methyl-1-butene, 1 -Hexen, 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-heptene, 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-Undecene, 1-Dodecene and the like. As the α-olefin, propylene, 1-butene, 1-pentene, 1-hexene and 1-octene are preferable. Further, the α-olefin is preferably an α-olefin having 4 to 20 carbon atoms, and among them, 1-butene, 1-pentene, 1-hexene and 1-octene are preferable. The α-olefin copolymerized with ethylene may be used alone or in combination of two or more.

The ethylene / α-olefin copolymer (B) according to the present invention is not particularly limited, but the content of the structural unit derived from ethylene is preferably 90 mol% or more in the total structural unit. Is desirable.
-Method for producing ethylene / α-olefin copolymer (B) The ethylene / α-olefin copolymer (B) according to the present invention is not limited in its production supplement method as described above, and is used at the time of production. The polymerization catalyst and the polymerization conditions are not particularly limited, but for example, it can be obtained by copolymerizing ethylene and the above-mentioned α-olefin in the presence of a known catalyst for olefin polymerization, and a metallocene-based catalyst is preferable. It can be obtained by copolymerizing in the presence of.
Propylene Resin Composition The propylene resin composition of the present invention contains 75 to 95% by mass of the above-mentioned propylene / ethylene block copolymer (A) and 5 to 5 to the above-mentioned ethylene / α-olefin copolymer (B). It is a resin composition containing 25% by mass. The propylene-based resin composition of the present invention preferably contains 75 to 90% by mass of the propylene / ethylene block copolymer (A) and 10 to 25% by mass of the ethylene / α-olefin copolymer (B).

Further, the propylene-based resin composition of the present invention contains components other than the propylene / ethylene block copolymer (A) and the ethylene / α-olefin copolymer (B) as long as the object of the present invention is not impaired. Although it may be preferable, the total of the propylene / ethylene block copolymer (A) and the ethylene / α-olefin copolymer (B) is 90% by mass or more, more preferably 93 of the total propylene resin composition. It is by mass% or more, more preferably 95% by mass or more. Examples of the components other than (A) and (B) include resin components other than (A) and (B), known additives, etc., but when used for retort packaging film applications, they are suitable for food packaging. It is desirable that the ingredients and contents are the same. As the additive, those known as additives to the olefin polymer can be used as long as the object of the present invention is not impaired. For example, an antioxidant, a nucleating agent, a lubricant, a flame retardant, and an antiblocking agent can be used. Agents, colorants, inorganic or organic fillers and the like can be mentioned.

The propylene-based resin composition of the present invention is not particularly limited, but a melt flow rate (MFR) measured at 230 ° C. under a load of 2.16 kg in accordance with ASTM D-1238 is preferably 2 to 8 g. / 10 minutes, more preferably 2-6 g / 10 minutes. A propylene-based resin composition having such a melt flow rate is preferable because it has good film moldability and can produce a film having excellent low-temperature impact resistance.

The propylene-based resin composition of the present invention is high by containing a propylene / ethylene block copolymer (A) and an ethylene / α-olefin copolymer (B) satisfying the above requirements in a specific amount ratio. It is suitable for producing films such as retort CPP films, and has excellent transparency and blocking resistance. Further, when a film, a laminated film, and a retort pouch made of the resin composition are manufactured, they have excellent heat-sealing properties, high heat-sealing strength, and maintain high heat-sealing strength even after high-temperature treatment such as retort sterilization treatment. In addition, it is excellent in transparency, rigidity, impact resistance at low temperature, and excellent quality as a high retort CPP film.
-Method for Producing Propylene Resin Composition The propylene resin composition of the present invention can be produced by various known methods. For example, a propylene / ethylene block copolymer (A), an ethylene / α-olefin copolymer (B) obtained in advance, and an additive or the like, if necessary, are blended to form a Henschel mixer, a ribbon blender, or a Banbury. Mixing using various known devices such as a mixer, or after mixing, using various known kneaders such as a single-screw extruder or a twin-screw extruder, a brabender or a roll, at 170 to 300 ° C. A method of melt-kneading at 190 to 250 ° C. is preferable.
<Film>
The film of the present invention is obtained from the above-mentioned propylene-based resin composition of the present invention, and includes a sheet-like material. The film of the present invention can be produced by a known method for molding an olefin polymer into a film. Such a film is excellent not only in heat sealability but also in shock absorption.

The film of the present invention can be produced, for example, by a film molding machine provided with a T-die or a circular die at the tip of the extruder.

The thickness of the film of the present invention can be variously determined depending on the application, but is usually in the range of 10 μm to 250 μm, preferably 15 μm to 200 μm. The film of the present invention is excellent in impact resistance at low temperatures even as a relatively thin film.

The film of the present invention may be a non-stretched (unstretched) film or a stretched film, but when used as a retort film, for example, a non-stretched film (CPP film) is preferable.

The film of the present invention can be used for various purposes as a single-layer film or a laminated film laminated with another layer. Preferred applications include, for example, food packaging materials, optical sheet and metal surface protection materials, medical packaging materials or freshness-preserving packaging materials, heat-sealing layers (sealing layers) of multi-layer retort packaging films described later, and the like. It is particularly suitable as a high retort CPP film.
<Laminated film>
The laminated film of the present invention has a layer made of the propylene-based resin composition of the present invention described above. The laminated film of the present invention is a film formed by laminating a layer made of the propylene-based resin composition of the present invention and one or more other layers, and is formed by pressure bonding, adhesion of each layer by an adhesive or the like, or a certain layer. It may be formed by any method such as integration by forming another layer on the layer or a combination thereof.

The laminated film of the present invention may have two or more layers, such as having layers made of a propylene-based resin composition on both sides, or may have an inner layer, and the composition is not limited. Preferably, a layer made of a propylene-based resin composition is provided as a surface layer on one surface. In such a laminated film, the layer made of the propylene-based resin composition acts as a heat-sealing layer and also has shock absorption, and is suitable as a film for retort packaging or the like.

When the laminated film of the present invention is a film for retort packaging, it preferably has a base material layer and a barrier layer in addition to the layer made of the propylene-based resin composition of the present invention, and further, a shock absorbing layer. Etc. may be possessed.

Examples of the base material layer include polyester resin films such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate films, polyamide films such as nylon 6 and nylon 66, ethylene / vinyl alcohol copolymer films, polyvinyl alcohol films, and polyvinyl chlorides. Examples thereof include films, polyvinylidene chloride films, polyolefin films such as polypropylene, paper, non-woven fabrics, and cloths. When the base material layer is a resin film, the film may be a non-stretched film or a film stretched in a uniaxial or biaxial direction. It is also preferable that such a base material layer has printability, heat resistance at the time of heat sealing, a protective function of the barrier layer, and the like.

As the barrier layer, a layer having a light-shielding property, a barrier property of oxygen or water vapor, or the like is preferable. For example, a metal such as aluminum or zinc, an oxide or an inorganic substance such as silica or aluminum oxide is vapor-deposited on a resin film such as PET. Examples thereof include an inorganic vapor-deposited film and an aluminum foil. Examples of the shock absorbing layer include a film such as polyester (nylon).

When the laminated film of the present invention is a high-retort packaging film, for example, it comprises a layer structure of a layer / barrier layer / base material layer made of the propylene-based resin composition of the present invention, and the propylene-based resin composition of the present invention. A suitable layer structure includes a layer / barrier layer / shock absorbing layer / base material layer. Further, an adhesive layer made of a known adhesive may be provided between each of these layers.

When such a laminated film is used as a high-retort packaging film, the layer made of the propylene-based resin composition of the present invention is usually on the food contact side and acts as a heat-sealed sealant layer.

The method for producing the laminated film of the present invention is not particularly limited as described above, and a known method can be adopted. For example, as a manufacturing method in the case of laminating a film made of the propylene-based resin composition of the present invention with another film or a laminated film, for example, a urethane-based or isocyanate-based anchor coating agent is applied on one surface. The propylene resin composition of the present invention is directly extruded and laminated on a film or a laminated film for laminating a layer made of the propylene resin composition of the present invention, or a method of laminating the other on the same. Or extrusion coating method and the like. Further, when the layer for laminating the layers made of the propylene-based resin composition of the present invention is formed from a thermoplastic resin, both resins can be directly molded into a laminated film by a coextrusion method.

When the laminated film of the present invention thus obtained is used as a packaging material, the heat-sealing strength (peeling strength of the heat-sealing portion) of the layer made of the propylene-based resin composition of the present invention is high, and the temperature is high. It retains high heat seal strength even after heat treatment such as high retort sterilization treatment performed under high pressure.

In the laminated film of the present invention, a heat seal layer having characteristics such as heat resistance, impact resistance at low temperature, high heat seal strength, and rigidity is formed on the surface, and high gas barrier property depending on the type of base material layer. It can be used in a wide range of applications including retort food packaging because it is further imparted with mechanical strength and the like. Further, this laminated film may be used as it is in the film shape, or may be used as a packaging material after being changed to the shape of a tray or a container.
<Retort pouch>
The retort pouch of the present invention comprises the above-mentioned laminated film having a layer made of the propylene-based resin composition according to the present invention as a surface layer on one surface. The retort pouch of the present invention is a package intended to be filled with contents such as food, retort sterilized at a high temperature, and stored for a long period of time, and among the laminated films forming the package in the form of a bag or the like. The layer made of the propylene-based resin composition according to the present invention serves as a heat-sealing layer (sealant layer) and also serves as a surface in contact with contents such as food. The laminated film constituting such a retort pouch preferably has a barrier layer and a base material layer in addition to the layer made of the propylene-based resin composition, and further has a shock absorbing layer and the like. Is also preferable. Such a retort pouch of the present invention has heat resistance, impact resistance at low temperature, heat seal strength, rigidity, gas barrier property, etc., is suitable for high retort sterilization at high temperature, and has advanced heat seal even after high temperature sterilization. It has strength and is excellent in long-term storage.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.

In Examples and Comparative Examples, various physical properties were measured or evaluated by the following methods.

(1) Melt flow rate (MFR)
According to ASTM D-1238, the propylene polymer (propylene / ethylene block copolymer) is at 230 ° C. under a load of 2.16 kg, and the ethylene polymer (ethylene / α-olefin copolymer) is at 190 ° C. , 2.16 kg load.

(2) Pentad isotactic fraction (mmmm fraction)
The pentad isotactic fraction (mmmm fraction) of the sample (propylene homopolymer) was determined by A.I. Based on the attribution shown in Macromolecules, 8,687 (1975) by zambelli et al., ^{Measured using 13} C-NMR under the following conditions, pentad isotactic fraction = (peak area at 21.7 ppm) / (Peak area at 19 to 23 ppm).
(3) Paraxylene-soluble component, insoluble component The ratio of the paraxylene-insoluble component is 5 g of the sample and 1 g of 2,6-di-tert-butyl-4-methylphenol (BHT) as an antioxidant in 700 ml of para-xylene. Is added, stirred while heating to raise the temperature to the boiling temperature, completely dissolved, then allowed to cool for 8 hours or more until the temperature reaches 25 ° C. while stirring, and the precipitated components are collected by filtration with a filter paper. Is a value obtained as an insoluble component. The ratio of the paraxylene-soluble component was set to a value obtained by subtracting the value of the insoluble component from the total amount of the sample.
(4) n-decane soluble component 200 ml of n-decane was added to 5 g of a sample and dissolved by heating at 145 ° C. for 30 minutes. It was cooled to 20 ° C. over about 3 hours and left for 30 minutes. Then, the precipitate (hereinafter, n-decane insoluble component) was filtered off. The filtrate was placed in about 3 times the amount of acetone to precipitate the components dissolved in n-decane (precipitate (A)). The precipitate (A) and acetone were separated by filtration, and the precipitate was dried. No residue was observed even when the filtrate side was concentrated to dryness.

The amount of n-decane-soluble component was calculated by the following formula.

n-Decan soluble part amount (mass%) = [precipitate (A) mass / sample mass] × 100
(5) Content of structural units derived from ethylene The content of structural units derived from ethylene in the paraxylene-soluble component of the propylene / ethylene block copolymer (A) is 1,2, for samples 20 to 30 mg. After dissolving in 0.6 ml of 4-trichlorobenzene / heavy benzene (2: 1) solution, carbon-nuclear magnetic resonance analysis ( ¹³ C-NMR) is performed, and propylene, ethylene, and α-olefin are quantified by the diad chain distribution. I asked.

For example, in the case of a propylene-ethylene copolymer
PP = Sαα, EP = Sαγ + Sαβ, EE = 1/2 (Sβδ + Sδδ) + 1/4 Sγδ
Was calculated by the following formulas (Eq-1) and (Eq-2).

Propene (mol%) = (PP + 1/2 EP) x 100 / [(PP + 1/2 EP) + (1/2 EP + EE)]… (Eq−1)
Ethylene (mol%) = (1/2 EP + EE) x 100 / [(PP + 1/2 EP) + (1/2 EP + EE)] ... (Eq-2)
(6) Extreme viscosity [η]
It was measured at 135 ° C. using a decalin solvent. About 20 mg of the sample was dissolved in 15 ml of decalin, and the specific viscosity ηsp was measured in an oil bath at 135 ° C. After diluting with 5 ml of a decalin solvent added to this decalin solution, the specific viscosity ηsp was measured in the same manner. This dilution operation was repeated twice more, and the value of ηsp / C when the concentration (C) was extrapolated to 0 was determined as the ultimate viscosity.

[Η] = lim (ηsp / C) (C → 0)
(7) Film transparency (haze value)
Measured according to JIS K 7105.
(8) Film blocking strength The chill roll surfaces of the film 10 cm in the MD direction × 10 cm in the TD direction are overlapped with each other, and held in a constant temperature bath at 80 ° C. under a load of ^{200 g / cm 2 for 3 days.}

Then, after adjusting the state in a room at 23 ° C. and 50% humidity for 24 hours or more, the peel strength when peeled at a tensile speed of 200 mm / min was measured, and the peel strength was divided by the width of the test piece (mN /). cm) was used as the blocking coefficient, and the blocking resistance was evaluated. Here, the smaller the blocking coefficient, the better the blocking resistance.
(9) Tensile modulus of film (MD)
According to JIS K7127, the measurement was carried out by a tensile tester under the conditions of cross head speed: 500 mm / min, measurement direction: machine direction (MD direction), and load cell: 10 kg.
(10) Impact resistance (film impact)
After adjusting the state of the sample at a predetermined temperature (-20 ° C) of ± 2 ° C and humidity of 50 ± 10% for 16 hours or more, 1 / in a film impact tester manufactured by Toyo Seiki Seisakusho under the same temperature and humidity conditions. It was evaluated by the impact fracture strength using a 2-inch impact head.
(11) Heat Seal Strength of Laminated Film Using a heat seal tester manufactured by Toyo Seiki, cut out a test piece with a width of 100 mm and a length of 150 mm from the laminated film, fold it in half, and set the specified heater temperature (200 ° C or 220 ° C). After heat-sealing under the conditions of pressure 0.2 MPa and sealing time 1 second, the sealed test piece was cut into a test piece with a width of 15 mm, and using Orientec Tencilon RT1225 type, peeling strength (N / 15 mm). ) Was measured and used as the heat seal strength before retort sterilization.

Further, the test piece prepared by the above method was placed in a hot water shower type high-pressure high-temperature sterilization device, treated at 121 ° C. for 30 minutes, and then cooled, and the peel strength (N / 15 mm) was increased by the same method as described above. ) Was measured and used as the heat seal strength after retort sterilization.
(12) Bag drop test Using a laminated film, a three-way seal bag having a length of 175 mm and a width of 125 mm was prepared using a bag making machine. The seal width is 10 mm. The prepared three-way seal bag was filled with 200 ml of water, air was bleeded, and the mouth was sealed.

Twenty such bags are prepared and allowed to stand for 24 hours in an atmosphere of 5 ° C. Then, one bag is dropped from a height of 10 cm so that the lateral direction is the falling direction, which is the same as the bag size. One set was a drop from the surface with a weight of 1300 g, and the number of drops was repeated up to 20 sets, and the number of times until the bag was broken was counted. The number of times until the 20 bags were prepared was averaged, and the average value was taken as the average number of bag breaks.

[Manufacturing Example 1]
(Production of Propylene / Ethylene Block Copolymer (A-1))
(1) Preparation of solid titanium catalyst component 95.2 g of anhydrous magnesium chloride, 442 ml of decan and 390.6 g of 2-ethylhexyl alcohol were heated at 130 ° C. for 2 hours to prepare a uniform solution, and then phthalic anhydride was added to this solution. 21.3 g of acid was added, and the mixture was further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride.

After cooling the uniform solution thus obtained to room temperature, 75 ml of this uniform solution was added dropwise over 200 ml of titanium tetrachloride kept at −20 ° C. for 1 hour. After charging, the temperature of this mixed solution was raised to 110 ° C. over 4 hours, 5.22 g of diisobutyl phthalate (DIBP) was added when the temperature reached 110 ° C., and the mixture was stirred at the same temperature for 2 hours. Retained.

After completion of the reaction for 2 hours, the solid part was collected by hot filtration, the solid part was resuspended in 275 ml of titanium tetrachloride, and then heated again at 110 ° C. for 2 hours. After completion of the reaction, the solid part was collected again by hot filtration and washed thoroughly with decane and hexane at 110 ° C. until no free titanium compound was detected in the solution.

The solid titanium catalyst component prepared as described above is stored as a hexane slurry, and a part of it was dried to examine the catalyst composition. The solid titanium catalyst component contained 2.3% by mass of titanium, 61% by mass of chlorine, 19% by mass of magnesium, and 12.5% by mass of DIBP.
(2) Production of Prepolymerization Catalyst 87.5 g of the solid titanium catalyst component prepared in (1), 19.5 mL of triethylaluminum, and 10 L of heptane are charged into an autoclave with an internal volume of 20 L and an internal temperature of 15 to 20 ° C. The mixture was charged with 263 g of propylene and reacted with stirring for 100 minutes. After completion of the polymerization, the solid component was precipitated, the supernatant was removed, and washing with heptane was performed twice. The obtained prepolymerization catalyst was resuspended in purified heptane and adjusted with heptane so that the solid catalyst component concentration was 0.7 g / L to obtain a catalyst slurry.
(3) Main polymerization In a vessel polymerizer with a stirrer having a content of 58 L, propylene was 30 kg / hour, hydrogen was 40 NL / hour, and the catalyst slurry produced in (2) above was used as a transition metal catalyst component at 0.44 g / hour, triethyl. Aluminum was continuously supplied at 4.9 mL / hour and dicyclopentyldimethoxysilane at 1.6 mL / hour, and polymerization was carried out in a fully liquid state in which no gas phase was present. The temperature of the tubular polymerizer was 70 ° C., and the pressure was 3.3 MPa / G (G = gauge pressure).

The obtained slurry was sent to a Vessel polymerizer with a stirrer having an internal volume of 70 L for further polymerization. Propylene was supplied to the polymerizer at 15 kg / hour, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 1.5 mol%. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 3.0 MPa / G.

The obtained slurry is transferred to a liquid transfer tube having an internal volume of 2.4 L, the slurry is gasified, and after air-solid separation, polypropylene homopolymer powder is sent to a gas phase polymerizer having an internal volume of 480 L to carry ethylene. / Propylene block copolymerization was performed. Propylene, ethylene, and hydrogen are continuously added so that the gas composition in the gas phase polymerizer is ethylene / (ethylene + propylene) = 0.20 (molar ratio) and hydrogen / ethylene = 0.078 (molar ratio). Supplied. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 1.0 MPa / G.

The obtained slurry was deactivated, vaporized, air-solidified, and vacuum dried at 80 ° C. As a result, a propylene / ethylene block copolymer (A-1) having a polypropylene part and an ethylene / propylene copolymer part was obtained.

Table 1 shows the physical characteristics of the obtained propylene / ethylene block copolymer (A-1).
(Manufacturing and evaluation of single-layer film)
Using the obtained propylene / ethylene block copolymer (A-1) and using a single-layer CPP tester (manufactured by Mitsubishi Heavy Industries, φ75 mm) as a film-forming machine, resin temperature setting: 250 ° C., chill roll temperature setting: 40 ° C. A film having a film thickness of 70 μm was extruded under the conditions of an air gap length of about 80 mm and a film forming speed of 40 m / min, and allowed to stand at 40 ° C. for 24 hours for aging to obtain a single-layer film. The transparency (haze value), blocking strength and tensile modulus of the obtained single-layer film were measured by the above-mentioned methods. The results are also shown in Table 1.
(Manufacturing and evaluation of laminated film)
A polyethylene terephthalate film (12 μm) / aluminum foil (7 μm) / single layer film (70 μm) obtained above is formed from the outer surface, and a dry lami adhesive for high retort CPP (polyester polyol type, solid content 35%) is layered between layers. The film was dry-laminated at a line speed of 80 m / min and aged at 40 ° C. for 5 days due to the effect of the adhesive to obtain a laminated film.

Using the obtained laminated film, the heat seal strength was evaluated and the body drop test was performed by the above-mentioned method. The results are also shown in Table 1.

[Manufacturing Example 2]
(Production of Propylene / Ethylene Block Copolymer (A-2))
(1) Preparation of solid titanium catalyst component 95.2 g of anhydrous magnesium chloride, 442 ml of decan and 390.6 g of 2-ethylhexyl alcohol were heated at 130 ° C. for 2 hours to prepare a uniform solution, and then phthalic anhydride was added to this solution. 21.3 g of acid was added, and the mixture was further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride.

After cooling the uniform solution thus obtained to room temperature, 75 ml of this uniform solution was added dropwise over 200 ml of titanium tetrachloride kept at −20 ° C. for 1 hour. After charging, the temperature of this mixed solution was raised to 110 ° C. over 4 hours, 5.22 g of diisobutyl phthalate (DIBP) was added when the temperature reached 110 ° C., and the mixture was stirred at the same temperature for 2 hours. Retained.

After completion of the reaction for 2 hours, the solid part was collected by hot filtration, the solid part was resuspended in 275 ml of titanium tetrachloride, and then heated again at 110 ° C. for 2 hours. After completion of the reaction, the solid part was collected again by hot filtration and washed thoroughly with decane and hexane at 110 ° C. until no free titanium compound was detected in the solution.

The solid titanium catalyst component prepared as described above is stored as a hexane slurry, and a part of it was dried to examine the catalyst composition. The solid titanium catalyst component contained 2.3% by weight of titanium, 61% by weight of chlorine, 19% by weight of magnesium, and 12.5% by weight of DIBP.
(2) Production of prepolymerization catalyst 100 g of solid catalyst component, 91.2 mL of triethylaluminum, 2-isobutyl, 2-isopropyl, 1,3 dimethoxypropane, 30.8 ml, and 10 L of heptane were inserted into an autoclave with a stirrer having an content of 20 L. The internal temperature was maintained at 15 to 20 ° C., 1000 g of propylene was inserted, and the reaction was carried out with stirring for 100 minutes. After completion of the polymerization, the solid component was precipitated, the supernatant was removed, and washing with heptane was performed twice. The obtained prepolymerization catalyst was resuspended in purified heptane and adjusted with heptane so that the solid catalyst component concentration was 0.75 g / L.
(3) Main polymerization In a vessel polymerizer with a stirrer having a content of 58 L, propylene was 30 kg / hour, hydrogen was 27 NL / hour, and the catalyst slurry produced in (2) above was used as a transition metal catalyst component at 0.33 g / hour, triethyl. 2.9 mL / hour of aluminum and 0.76 mL / hour of dicyclopentyldimethoxysilane were continuously supplied, and polymerization was carried out in a full liquid state in which no gas phase was present. The temperature of the tubular polymerizer was 70 ° C. and the pressure was 3.3 MPa / G.

The obtained slurry was sent to a Vessel polymerizer with a stirrer having an internal volume of 70 L for further polymerization. Propylene was supplied to the polymerizer at 15 kg / hour, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 2.2 mol%. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 3.0 MPa / G.

The obtained slurry is transferred to a liquid transfer tube having an internal volume of 2.4 L, the slurry is gasified, and after air-solid separation, polypropylene homopolymer powder is sent to a gas phase polymerizer having an internal volume of 480 L to carry ethylene. / Propylene block copolymerization was performed. Propylene, ethylene, and hydrogen are continuously added so that the gas composition in the gas phase polymerizer is ethylene / (ethylene + propylene) = 0.1965 (molar ratio) and hydrogen / ethylene = 0.1296 (molar ratio). Supplied. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 1.1 MPa / G.

The obtained slurry was deactivated, vaporized, air-solidified, and vacuum dried at 80 ° C. As a result, a propylene / ethylene block copolymer (A-2) having a polypropylene part and an ethylene / propylene copolymer part was obtained.

Table 1 shows the physical properties of the obtained propylene / ethylene block copolymer (A-2) and the physical property evaluation results of the single-layer film and the laminated film prepared using the same as in Production Example 1.

[Manufacturing Example 3]
(Production of Propylene / Ethylene Block Copolymer (A'-3))
(1) Preparation of the solid titanium catalyst component and (2) production of the prepolymerization catalyst were carried out in the same manner as in Production Example 2.
(3) Main polymerization In a vessel polymerizer with a stirrer having a content of 58 L, propylene was 30 kg / hour, hydrogen was 27 NL / hour, and the catalyst slurry produced in (2) above was used as a transition metal catalyst component at 0.33 g / hour, triethyl. 2.9 mL / hour of aluminum and 0.76 mL / hour of dicyclopentyldimethoxysilane were continuously supplied, and polymerization was carried out in a full liquid state in which no gas phase was present. The temperature of the tubular polymerizer was 70 ° C. and the pressure was 3.3 MPa / G.

The obtained slurry was sent to a Vessel polymerizer with a stirrer having an internal volume of 70 L for further polymerization. Propylene was supplied to the polymerizer at 15 kg / hour, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 2.2 mol%. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 3.0 MPa / G.

The obtained slurry is transferred to a liquid transfer tube having an internal volume of 2.4 L, the slurry is gasified, and after air-solid separation, polypropylene homopolymer powder is sent to a gas phase polymerizer having an internal volume of 480 L to carry ethylene. / Propylene block copolymerization was performed. Propylene, ethylene, and hydrogen are continuously added so that the gas composition in the gas phase polymerizer is ethylene / (ethylene + propylene) = 0.3175 (molar ratio) and hydrogen / ethylene = 0.1283 (molar ratio). Supplied. Polymerization was carried out at a polymerization temperature of 70 ° C. and a pressure of 1.1 MPa / G.

The obtained slurry was deactivated, vaporized, air-solidified, and vacuum dried at 80 ° C. As a result, a propylene / ethylene block copolymer (A'-3) having a polypropylene part and an ethylene / propylene copolymer part was obtained.

Table 1 shows the physical characteristics of the obtained propylene / ethylene block copolymer (A'-3) and the physical characteristics evaluation results of the single-layer film and the laminated film prepared using the same as in Production Example 1.

[Manufacturing Example 4]
(Production of Propylene / Ethylene Block Copolymer (A'-4))
(1) Preparation of Magnesium Compound A reaction tank with a stirrer having an internal volume of 500 liters is sufficiently replaced with nitrogen gas, 97.2 kg of ethanol, 640 g of iodine and 6.4 kg of metallic magnesium are added, and then the reflux condition is performed while stirring. The reaction was carried out in the system until no hydrogen gas was generated, and a physical reaction product was obtained. The reaction solution containing this solid reaction product was dried under reduced pressure to obtain the desired magnesium compound (solid product).
(2) Preparation of solid catalyst components In a reaction vessel with a stirrer having an internal volume of 500 liters sufficiently replaced with nitrogen gas, 30 kg of the magnesium compound (uncrushed) obtained in (1) above, 150 liters of purified heptane, 4.5 liters of silicon tetrachloride and 4.3 liters of diethyl phthalate were charged. The inside of the system was kept at 90 ° C., 144 liters of titanium tetrachloride was added with stirring, and the mixture was reacted at 110 ° C. for 2 hours, and then the solid components were separated and washed with purified heptane at 80 ° C. Further, 228 liters of titanium tetrachloride was added and reacted at 110 ° C. for 2 hours, and then thoroughly washed with purified heptane to obtain a solid catalyst component.
(3) Prepolymerization 230 liters of purified heptane was put into a reaction vessel with a stirrer having an internal volume of 500 liters, 25 kg of the solid catalyst component obtained in (2) above was added, and then Ti atoms in the solid catalyst component were added. After adding 0.6 mol of triethylaluminum and 0.4 mol of cyclohexylmethyldimethoxysilane to 1 mol, propylene ^{was introduced at a partial pressure of propylene until it reached 0.3 kg / cm 2} G, and the temperature was 25 ° C. Was reacted for 4 hours. After completion of the reaction, the solid catalyst component was washed with purified heptane several times, carbon dioxide was supplied, and the mixture was stirred for 24 hours.
(4) Main Polymerization As the first stage of polymerization, triethylaluminum was added to a polymerization apparatus (R-1) with a stirrer having an internal volume of 200 liters by adding the treated solid catalyst component of (3) above to 3 mmol / hr in terms of Ti atoms. Propylene gas containing 0.07 mol% of hydrogen, supplied with cyclohexylmethyldimethoxysilane at 105 mmol / hr (1.9 mmol / kg-PP) at 413 mmol / hr (7.5 mmol / kg-PP), respectively. Was supplied, and propylene was polymerized at a polymerization temperature of 75 ° C. and a total pressure of 30 kg / cm ^{2 G.}

Next, the powder was continuously extracted from R-1 and transferred to a polymerization apparatus (R-2) with a stirrer having an internal volume of 200 liters. In (R-2), propylene, ethylene and hydrogen are supplied in a gas composition having a ratio of propylene: 81.4 mol%, ethylene: 14.5 mol% and hydrogen: 4.1 mol%, and the polymerization temperature is 50 ° C. Propylene and ethylene were copolymerized at a total pressure of 11 kg / cm ^{2 G.}

A propylene / ethylene block copolymer (A'-4) was obtained by such a polymerization method.

Table 1 shows the physical characteristics of the obtained propylene / ethylene block copolymer (A'-4) and the physical property evaluation results of the single-layer film and the laminated film prepared using the same as in Production Example 1.

［実施例１］
（プロピレン系樹脂組成物（１）の製造）
製造例１で得たプロピレン・エチレンブロック共重合体（Ａ−１）８０質量部と、エチレン・ヘキセン−１共重合体であるエチレン・α−オレフィン共重合体（Ｂ−１）（（株）プライムポリマー製、商品名：エボリュー（登録商標）ＳＰ０５１０、ＭＦＲ：１．２ｇ／１０分、密度９０４ｋｇ／ｍ³、ｎ−デカン可溶成分２．３質量％）２０重量部とを配合し、二軸混練機で混練・造粒して、プロピレン系樹脂組成物（１）を得た。

[Example 1]
(Manufacturing of Propylene Resin Composition (1))
80 parts by mass of the propylene / ethylene block copolymer (A-1) obtained in Production Example 1 and an ethylene / α-olefin copolymer (B-1) (Co., Ltd.) which is an ethylene / hexene-1 copolymer. Made of prime polymer, trade name: Evolu (registered trademark) SP0510, MFR: 1.2 g / 10 minutes, density 904 kg / m ³ , n-decane-soluble component 2.3% by mass) 20 parts by weight. A propylene-based resin composition (1) was obtained by kneading and granulating with a shaft kneader.

Using the obtained propylene-based resin composition (1), a single-layer CPP tester (manufactured by Mitsubishi Heavy Industries, φ75 mm) was used as a film-forming machine, and a resin temperature setting: 250 ° C., a chill roll temperature setting: 40 ° C., an air gap. A film having a thickness of 70 μm was extruded under the conditions of a length of about 80 mm and a film forming speed of 40 m / min, and allowed to stand at 40 ° C. for 24 hours for aging to obtain a single-layer film. The transparency (haze value), blocking strength and tensile modulus of the obtained single-layer film were measured by the above-mentioned methods. The results are shown in Table 2.
(Manufacturing and evaluation of laminated film)
A polyethylene terephthalate film (12 μm) / aluminum foil (7 μm) / single layer film (70 μm) obtained above is formed from the outer surface, and a dry lami adhesive for high retort CPP (polyester polyol type, solid content 35%) is layered between layers. The film was dry-laminated at a line speed of 80 m / min and aged at 40 ° C. for 5 days due to the effect of the adhesive to obtain a laminated film.

Using the obtained laminated film, the heat seal strength was evaluated at heat seal temperatures of 200 ° C. and 220 ° C., and a body drop test was performed by the above method. The results are also shown in Table 2.

[Example 2]
Example 1 except that the propylene / ethylene block copolymer (A-2) obtained in Production Example 2 was used instead of the propylene / ethylene block copolymer (A-1) in Example 1. A propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in the above, and each property was evaluated. The results are shown in Table 2.

[Example 3]
In Example 2, the blending amount of the propylene / ethylene block copolymer (A-2) and the ethylene / α-olefin copolymer (B-1) is adjusted to the propylene / ethylene block copolymer (A-2) 90. A propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in Example 2, except that the parts were changed to 10 parts by mass of the ethylene / α-olefin copolymer (B-1). Each property was evaluated. The results are shown in Table 2.

[Comparative Example 1]
In Example 1, the propylene / ethylene block copolymer (A'-3) obtained in Production Example 3 was used instead of the propylene / ethylene block copolymer (A-1). A propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in 1, and each property was evaluated. The results are shown in Table 2.

[Comparative Example 2]
In Comparative Example 1, the blending amount of the propylene / ethylene block copolymer (A'-3) and the ethylene / α-olefin copolymer (B-1) was adjusted to the propylene / ethylene block copolymer (A'-3). ) 90 parts by mass and 10 parts by mass of the ethylene / α-olefin copolymer (B-1) were used to produce a propylene resin composition, a single-layer film and a laminated film in the same manner as in Comparative Example 1. Then, each property was evaluated. The results are shown in Table 2.

[Comparative Example 3]
In Comparative Example 1, instead of the ethylene / α-olefin copolymer (B-1), the MFR was 4 g / 10 minutes, the density was 918 kg / m ³ , and the amount of the n-decane-soluble component was 0.5% by mass. Comparison except that ethylene / α-olefin copolymer (B-2) (manufactured by Prime Polymer Co., Ltd., trade name: Evolu (registered trademark) SP2040), which is an ethylene / hexene-1 copolymer, was used. A propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in Example 1, and their properties were evaluated. The results are shown in Table 2.

[Comparative Example 4]
In Example 3, in place of the ethylene · alpha-olefin copolymer (B-1), MFR is 0.5 g / 10 min, a density of 885kg / m ³ of ethylene · alpha-olefin copolymer (B-3 ) (Mitsui Chemicals Co., Ltd., trade name: Toughmer (registered trademark) A0585), a propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in Example 3. , Each property was evaluated. The results are shown in Table 2.

[Comparative Example 5]
In Comparative Example 1, instead of the ethylene / α-olefin copolymer (B-1), ethylene having an MFR of 4.0, a density of 911 kg / m ³ , and an n-decane-soluble component amount of 3.3% by mass. A propylene-based resin composition, a single-layer film, and a laminated film were produced in the same manner as in Comparative Example 1 except that the α-olefin copolymer (B-4) (Ultzex 1540L made of prime polymer) was used. , Each property was evaluated. The results are shown in Table 2.

Possibility of industrial use

The propylene-based resin composition of the present invention is suitable for producing a film or a laminated film having a high degree of heat-sealing property, heat resistance, and impact resistance at a low temperature, and the film is a packaging body accompanied by high retort high-temperature sterilization. It is suitable for applications, and can be suitably used for applications such as packaging films, retort pouches, and retort containers.

Claims (7)

75 to 95% by mass of propylene / ethylene block copolymer (A) satisfying the following requirements (a-1) to (a-4).
A propylene resin composition containing 5 to 25% by mass of an ethylene / α-olefin copolymer (B) satisfying the following requirements (b-1) and (b-2).
(A-1) The melt flow rate (230 ° C., 2.16 kg load) is 2.0 to 8.0 g / 10 minutes.
(A-2) The amount of the paraxylene-soluble component is 15% by mass or more, and the amount of the para-xylene-soluble component (mass%) and the amount of the n-decane-soluble component (% by mass) are the following relational expressions. Satisfy (1).
Amount of n-decane-soluble component ≤ Amount of para-xylene-soluble component x 0.95 ... (1)
(A-3) The content of the structural unit derived from ethylene in the paraxylene-soluble component is 20 to 30% by mass.
(A-4) The pentad isotactic fraction in the paraxylene insoluble component is 94 mol% or more.
(B-1) The melt flow rate (190 ° C., 2.16 kg load) is 0.5 to 5.0 g / 10 minutes.
(B-2) a density of ^{890kg / m 3 ~910kg / m 3} . The propylene-based resin composition according to claim 1, wherein the ethylene / α-olefin copolymer (B) further satisfies the requirement (b-3).
(B-3) The density X (kg / m ³ ) and the amount of n-decane-soluble component Y (mass%) satisfy the following relational expression (2).
^{Y ≦ 0.0046X 2 -8.578X + 4000 ...} (2) A film comprising the propylene-based resin composition according to claim 1 or 2. The film according to claim 3, which is a non-stretched film. A laminated film having a layer made of the propylene-based resin composition according to claim 1 or 2. The laminated film according to claim 5, wherein the layer made of the propylene-based resin composition according to claim 1 or 2 is provided as a surface layer on one surface. A retort pouch made of the laminated film according to claim 6.