Polypropylene resin composition for non-stretched film and film

Abstract

To provide a polypropylene resin composition which can reduce the used amount of resources through the thinning of a film, more specifically, has favorable properties in either or both rigidity and HAZE, even when thinned, and a non-stretched film composed of the polypropylene resin composition.SOLUTION: A polypropylene resin composition for a non-stretched film contains (1) 1 to 50 wt.% of a polypropylene resin (X) satisfying characteristics (X-1) to (X-4), (2) 99 to 50 wt.% of a polypropylene resin (Y) satisfying characteristic (Y-1), and (3) 0.01 to 1 wt.% of a crystal nucleating agent (A) (provided that total amount of polypropylene resin (X) and polypropylene resin (Y) is 100 wt.%).

Description

[Technical field]

[0001] The present invention relates to a non-oriented polypropylene film, and more particularly to a polypropylene resin composition for a non-oriented film which has higher rigidity, excellent optical properties such as transparency and gloss, and a well-balanced tear strength compared to conventional polypropylene films, and a non-oriented film made of the polypropylene resin composition. [Background technology]

[0002] Polypropylene is a typical general-purpose resin. Its films are widely used in the packaging industry due to their good balance of optical properties, mechanical properties, and packaging suitability, and are particularly used for food packaging. In recent years, there has been a demand for thinner films from the perspective of reducing raw material costs, improving productivity through high-speed film production, cost reduction through weight reduction, and environmental issues. However, excessive thinning leads to a decrease in the stiffness, or rigidity, of the film. As a result, not only does this adversely affect transportability and unwinding from a roll during film processing, but it also leads to a decrease in the inherent functions of the final package, such as protecting the contents and maintaining the shape.

[0003] To solve this problem, the film can be made more rigid. The main methods for increasing rigidity include adding a nucleating agent, which is a crystallization promoter, or adding resin-reinforcing fillers such as talc, carbon nanofiber, or cellulose nanofiber. However, when inorganic nucleating agents are added, they act as foreign matter and cause a defect in the appearance of the film known as fish eyes, while when organic network nucleating agents are added, there is a risk that the contents of the package will be contaminated by low molecular weight components derived from the nucleating agent. Furthermore, when resin-reinforcing fillers are added, not only do they significantly change the feel, texture, and optical properties, but they also increase the specific gravity, making them unsuitable for the purpose of reducing weight.

[0004] Although a method of adding an alicyclic hydrocarbon resin component such as a petroleum resin has been proposed, the alicyclic hydrocarbon resin component is expensive and is not suitable for the purpose of increasing rigidity for cost reduction, such as improving productivity or reducing weight.

[0005] It is also possible to increase rigidity by adjusting the film-forming conditions, such as by promoting oriented crystallization by lowering the extrusion temperature or promoting crystal growth by increasing the cooling and solidification temperature. However, this is not a preferred method because it results in a deterioration in the thickness accuracy of the obtained film and changes in the optical properties. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-3364 [Patent Document 2] Japanese Patent Application Publication No. 9-118776 [Patent Document 3] JP 2008-127487 A [Patent Document 4] JP 2011-236357 A [Patent Document 5] JP 2016-11380 A [Patent Document 6] Patent Publication No. 2021-4359 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention aims to provide a film that has high rigidity and transparency and few fisheyes, which could not be obtained by conventional techniques for adding a nucleating agent, and that can reduce the amount of resources used by increasing the rigidity of the film. More specifically, it is an object of the present invention to provide a polypropylene resin composition that can maintain high rigidity even when made thin, and a non-oriented film made of the polypropylene resin composition. [Means for solving the problem]

[0008] [1] (1) 1 to 50% by weight of polypropylene resin (X) satisfying the following properties (X-1) to (X-4), (2) 99 to 50% by weight of a polypropylene resin (Y) satisfying the following characteristic (Y-1), and (3) containing 0.01 to 1% by weight of a crystal nucleating agent (A); Polypropylene resin composition for non-oriented film (wherein the total amount of polypropylene resin (X) and polypropylene resin (Y) is 100% by weight). (X-1) MFR (230°C, load 2.16 kgf) is 0.1 to 30.0 g / 10 min. (X-2) The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) obtained by GPC is 3.0 to 10.0. (X-3) The melt tension (MT) (unit: g) measured at 230°C satisfies the relationship of the following (Equation 1) or (Equation 2). log(MT)≧-0.9×log(MFR)+0.7 (Formula 1) MT≧15 (Formula 2) (X-4) The branching index g' measured by GPC is 0.30 or more and less than 0.95. (Y-1) MFR (230°C, load 2.16 kgf) is 1 to 30 g / 10 min. [2] The polypropylene resin composition for use in a non-oriented film according to [1], wherein the polypropylene resin (Y) is a propylene homopolymer. [3] A non-stretched film comprising the polypropylene resin composition for non-stretched films according to [1] or [2]. [4] A multilayer film comprising a layer made of the non-oriented film according to [3]. [5] A food packaging film comprising the non-oriented film described in [3]. [6] A protective film comprising the non-oriented film according to [3]. [7] A synthetic paper comprising the non-oriented film according to [3]. Effect of the Invention

[0009] The present invention makes it possible to reduce the amount of resources used by reducing the thickness of the film, and more specifically, it is possible to provide a polypropylene resin composition that retains high rigidity even when made thin, and a non-oriented film made of the polypropylene resin composition. Furthermore, the present invention enables the production of thinner films, which in turn reduces the amount of resin used and the production costs of the films, which is also excellent from the standpoint of environmental issues. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following describes in detail the embodiments of the present invention, item by item. In this specification, the term "to" indicates a range of values, and includes the values ​​before and after the range as the lower and upper limits. The following description of the constituent elements is an example of the embodiment of the present invention, and the present invention is not limited to these contents in any way.

[0011] 1. Polypropylene resin composition for non-oriented films The polypropylene resin composition for non-oriented films of the present invention comprises: (1) 1 to 50% by weight of polypropylene resin (X) having the following properties (X-1) to (X-4), (2) 99 to 50% by weight of a polypropylene resin (Y) having the following characteristic (Y-1), and (3) containing 0.01 to 1% by weight of a crystal nucleating agent (A); (However, the total amount of polypropylene resin (X) and polypropylene resin (Y) is 100% by weight.) (X-1) MFR (230°C, load 2.16 kgf) is 0.1 to 30 g / 10 min. (X-2) The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) obtained by GPC is 3.0 to 10.0. (X-3) The melt tension (MT230°C) (unit: g) measured at 230°C satisfies the relationship of the following (Equation 1) or (Equation 2). log(MT)≧-0.9×log(MFR)+0.7 (Formula 1) MT≧15 (Formula 2) (X-4) The branching index g' measured by GPC is 0.30 or more and less than 0.95. (Y-1) MFR (230°C, load 2.16 kgf) is 1 to 30 g / 10 min.

[0012] 1-1. Polypropylene resin (X) The polypropylene resin (X) has the properties (X-1) to (X-4).

[0013] 1-1-1. Characteristics (X-1): MFR (230°C, load 2.16 kgf) is 0.1 to 30 g / 10 min. MFR is an index of melt fluidity, and the higher the molecular weight of a polymer, the smaller this value becomes. Conversely, the lower the molecular weight, the larger this value becomes. When the MFR is 0.1g / 10min or more, the melt flowability is good, and the load on the extruder is low, making it easy to mold. On the other hand, when the MFR is 30g / 10min or less, the melt tension is high, so necking and film rupture do not occur, making it easy to mold into a film. Therefore, the MFR is 0.1 to 30 g / 10 min, preferably 1 to 20 g / 10 min, more preferably 2 to 15 g / 10 min, and further preferably 7 to 10 g / 10 min. In the present invention, the melt flow rate (MFR) is a value measured in accordance with JIS K7210:2014 "Test method for melt mass flow rate (MFR) and melt volume flow rate (MVR) of plastics-thermoplastics" under test conditions of 230°C and a load of 2.16 kgf. The melt flow rate (MFR) can be easily adjusted by changing the polymerization temperature or pressure, or, as a general method, by adding a chain transfer agent such as hydrogen during polymerization.

[0014] 1-1-2. Property (X-2): The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) obtained by GPC is 3.0 to 10.0.

[0015] Mw / Mn is an index showing the spread of the molecular weight distribution, and the larger this value, the wider the molecular weight distribution. If Mw / Mn is too small, the amount of low molecular weight components decreases, resulting in poor melt fluidity. Therefore, if Mw / Mn is 3.0 or more, the amount of low molecular weight components increases, improving melt fluidity. Mw / Mn is preferably 3.1 or more, more preferably 3.2 or more. On the other hand, if Mw / Mn is 10.0 or less, the amount of high molecular weight components decreases relatively, improving melt fluidity. Mw / Mn is preferably 9.6 or less, more preferably 9.2 or less.

[0016] Similarly, Mz / Mw is an index showing the spread of the molecular weight distribution, and is an index showing the spread on the high molecular weight side compared to Mw / Mn. The larger these values ​​are, the broader the molecular weight distribution is toward the high molecular weight side. If Mz / Mw is 2 or more, the amount of high molecular weight components increases and the melt tension improves. Therefore, Mz / Mw is preferably 2.0 or more, more preferably 2.1 or more, and more preferably 2.2 or more. On the other hand, if Mz / Mw is 5.0 or less, the amount of high molecular weight components relatively decreases and the melt fluidity improves. Therefore, Mz / Mw is 5.0 or less, preferably 4.5 or less, and more preferably 4.0 or less.

[0017] 1-1-3. Property (X-3): The melt tension measured at 230°C (MT; can also be written as MT230°C) (unit: g) satisfies the requirement of the following (Formula 1) or (Formula 2). log(MT)≧-0.9×log(MFR)+0.7 (Formula 1) MT≧15 (Formula 2)

[0018] Here, MT230°C represents the melt tension measured using a Capillograph 1B manufactured by Toyo Seiki Seisakusho Co., Ltd. under the following conditions: capillary diameter: 2.0 mm, length: 40 mm, cylinder diameter: 9.55 mm, cylinder extrusion speed: 20 mm / min, take-up speed: 4.0 m / min, temperature: 230°C, and the unit is grams. However, if the MT of the sample is extremely high, the resin may break at a take-up speed of 4.0 m / min. In such a case, the take-up speed is reduced, and the tension at the highest possible take-up speed is taken as MT. The measurement conditions and units of MFR are as described above.

[0019] (Formula 1) is an index for polypropylene resin (X) to have sufficient melt tension, and since MT generally has a correlation with MFR, it is described by a relational expression with MFR. The relational expression between MT and MFR is expressed by (Formula 1): log(MT)≧-0.9×log(MFR)+0.7, preferably log(MT)≧-0.9×log(MFR)+1.0 (Formula 1a), and more preferably log(MT)≧-0.9×log(MFR)+1.5 (Formula 1b). If the polypropylene resin (X) satisfies the above formula (1), not only can the neck-in be reduced, but also stress is uniformly propagated in the molten film, thereby suppressing the phenomenon of uneven film thickness, known as the resonance phenomenon, and instability due to expansion and contraction of the edges.

[0020] The polypropylene resin (X) must satisfy the requirements of (formula 1) or (formula 2), and in that case, the stiffness of the film will be high.

[0021] Regarding the upper limit of MT, if MT is 40g or less, the resin has extensibility and the above measurement becomes easy. In addition, film breakage during molding does not occur. Therefore, MT is preferably 40g or less, more preferably 37g or less, and even more preferably 35g or less. In order to satisfy the requirement of the above formula (1), for example, the amount of long chain branches in the polypropylene resin (X) may be increased to increase the melt tension. For example, it is possible to introduce a large amount of long chain branches by controlling the types, combinations, amount ratios, prepolymerization conditions, etc. of the preferred metallocene catalysts described below.

[0022] 1-1-4. Characteristics (X-4): The branching index g' measured by GPC is 0.30 or more and less than 0.95.

[0023] The branching index g' can be used as a direct indicator of whether polypropylene resin (X) has branches. g' is given by the ratio of the intrinsic viscosity [η]br of a polymer having a long chain branching structure to the intrinsic viscosity [η]lin of a linear polymer having the same molecular weight, i.e., [η]br / [η]lin, and takes a value smaller than 1 when a long chain branching structure is present. In other words, polypropylene with g'<1 is a "long-chain branched polypropylene." The definitions are described, for example, in "Developments in Polymer Characterization-4" (JV Dawkins ed. Applied Science Publishers, 1983), and are known guidelines for those skilled in the art.

[0024] g' can be obtained as a function of the absolute molecular weight Mabs, for example, by using GPC equipped with a light scattering meter and a viscometer as detectors as described below. The polypropylene resin (X) used in the present invention preferably has a g' value of the component having an absolute molecular weight Mabs of 1 million as determined by light scattering of 0.40 or more and less than 0.93, more preferably 0.50 or more and less than 0.92, and even more preferably 0.60 or more and less than 0.91. If g' is 0.40 or more, highly cross-linked components are not formed, and gel formation is absent or very minimal. On the other hand, if g' is 0.93 or less, the performance of the resin that forms a long-chain branched structure is expressed, resulting in high rigidity.

[0025] In addition, a branched polymer having a comb structure is preferable because the degree of decrease in melt tension is small when kneaded at high temperatures of 290°C or higher or when kneading is repeated, and therefore the deterioration of film formability (increase in neck-in or occurrence of resonance phenomenon during slow take-up) is unlikely to occur. A specific method for calculating g' is as follows. The GPC apparatus used is Alliance GPCV2000 manufactured by Waters, equipped with a differential refractometer (RI) and a viscosity detector (Viscometer). The light scattering detector used is a multi-angle laser light scattering detector (MALLS) DAWN-E manufactured by Wyatt Technology. The detectors are connected in the order of MALLS, RI, and Viscometer. The mobile phase solvent is 1,2,4-trichlorobenzene (with the antioxidant Irganox1076 manufactured by BASF Japan added at a concentration of 0.5 mg / mL). The flow rate is 1 mL / min, and two Tosoh GMHHR-H(S) HT columns are connected together. The temperatures of the columns, sample injection section, and each detector are 140° C. The sample concentration is 1 mg / mL, and the injection volume (sample loop volume) is 0.2175 mL. To calculate the absolute molecular weight (Mabs), the root mean square radius of gyration (Rg) obtained from MALLS, and the intrinsic viscosity ([η]) obtained from Viscometer, the data processing software ASTRA (version 4.73.04) attached to MALLS is used, and calculations are performed with reference to the following literature. References: 1. “Developments in Polymer Characterization-4” (JV Dawkins ed. Applied Science Publishers, 1983.Chapter1.) 2.Polymer, 45, 6495-6505 (2004) 3.Macromolecules,33,2424-2436(2000) 4.Macromolecules,33,6945-6952(2000)

[0026] [Calculation of branching index (g')] The branching index (g') is calculated as the ratio ([η]br / [η]lin) of the intrinsic viscosity ([η]br) obtained by measuring a sample with the above-mentioned Viscometer to the intrinsic viscosity ([η]lin) obtained by separately measuring a linear polymer. When a long chain branch structure is introduced into a polymer molecule, the radius of gyration becomes smaller compared to a linear polymer molecule of the same molecular weight. Since a smaller radius of gyration results in a smaller intrinsic viscosity, the ratio ([η]br / [η]lin) of the intrinsic viscosity of the branched polymer to the intrinsic viscosity ([η]lin) of the linear polymer of the same molecular weight becomes smaller as the long chain branch structure is introduced. Therefore, when the branching index (g'=[η]br / [η]lin) is a value smaller than 1, it means that the polymer has a long chain branched structure. Here, a commercially available homopolypropylene (Novatec PP (registered trademark) grade name: FY6, manufactured by Japan Polypropylene Corporation) is used as the linear polymer for obtaining [η]lin. It is known that the logarithm of [η]lin of a linear polymer has a linear relationship with the logarithm of the molecular weight, as known as the Mark-Houwink-Sakurada equation, and therefore the value of [η]lin can be obtained by appropriately extrapolating to the low molecular weight side or the high molecular weight side.

[0027] The branching index g' can be adjusted to 0.30 or more and less than 0.95 by introducing a large amount of long chain branches, for example, by controlling the type of preferred metallocene catalyst, the combination ratio, prepolymerization conditions, etc.

[0028] 1-1-5. The polypropylene resin (X) of the present invention preferably satisfies the following property (X-5): Characteristics (X-5): 13 The mm fraction of propylene unit triads measured by C-NMR is 95% or more.

[0029] The polypropylene resin (X) of the present invention preferably has high stereoregularity. The degree of stereoregularity is as follows: 13 It can be evaluated by C-NMR. 13It is preferable that the mm fraction of propylene unit triads obtained by C-NMR has a stereoregularity of 95% or more. The mm fraction is the percentage of propylene unit triads in which the direction of the methyl branch in each propylene unit is the same among any propylene unit triads consisting of head-to-tail bonds in a polymer chain, and therefore the upper limit is 100%. This mm fraction is a value indicating that the three-dimensional structure of the methyl group in the polypropylene molecular chain is isotactically controlled, and the higher the mm fraction, the higher the degree of control. If the mm fraction is higher than a certain value, the elastic modulus of the product is improved and the rigidity of the film is increased. Therefore, the mm fraction is 95% or more, more preferably 96% or more, and even more preferably 97% or more.

[0030] In addition, 13 The details of the method for measuring the mm fraction of propylene unit triads by C-NMR are as follows. 375 mg of sample is completely dissolved in 2.5 ml of deuterated 1,1,2,2-tetrachloroethane in an NMR sample tube (10φ), and then measured at 125°C using the proton complete decoupling method. The chemical shift is set to 74.2 ppm for the central peak of the three peaks of deuterated 1,1,2,2-tetrachloroethane. The chemical shifts of the other carbon peaks are based on this. Flip angle: 90 degrees Pulse Interval: 10 seconds ·Resonance frequency: 100MHz or more -Number of times: 10,000 or more Observation range: -20ppm to 179ppm Number of data points: 32768

[0031] The mm fraction of propylene unit triads is 13 Measured by C-NMR 13 The integrated intensity of the C signal is calculated by substituting it into the following equation. mm(%)=Imm×100 / (Imm+3×Imrrm) Here, Imm=I 23.6~21.1 , Imrrm=I 19.8~19.7 This is the quantity indicated by: To calculate the mm fraction of propylene unit triads 13 The C-NMR measurement can be performed in the same manner as the above measurement. Spectral assignments can be made with reference to Polymer Jounral, vol. 16, p. 717 (1984), Asakura Publishing, Macromolecules, vol. 8, p. 687 (1975), and Polymer, vol. 30, p. 1350 (1989).

[0032] The mm fraction can be increased to 95% or more by using a polymerization catalyst that produces a highly crystalline polymer, and this can be achieved by polymerization using a preferred metallocene catalyst described below.

[0033] 1-1-6. Manufacturing method of polypropylene resin (X) The polypropylene resin (X) is not particularly limited in the production method as long as it satisfies the above-mentioned characteristics (X-1) to (X-2). However, as described above, a preferred production method for satisfying the conditions of high stereoregularity, a relatively wide molecular weight distribution, a range of branching index g', high melt tension, etc. is a method using a macromer copolymerization method using a combination of metallocene catalysts. An example of such a method is, for example, the method disclosed in JP-A-2009-57542. This method is a method for producing polypropylene having a long chain branching structure using a catalyst that combines a catalyst component having a specific structure capable of generating a macromer and a catalyst component having a specific structure capable of copolymerizing a macromer. According to this method, it is possible to produce a polypropylene resin having a long chain branching structure with the desired physical properties by an industrially effective method such as bulk polymerization or gas phase polymerization, particularly by single-stage polymerization under practical pressure and temperature conditions, and by using hydrogen as a molecular weight regulator. The macromer copolymerization method can obtain a polypropylene resin containing long chain branches without generating gel, and is suitable for the present invention. In addition, since the polypropylene resin produced by the macromer copolymerization method is not crosslinked, it has good recyclability.

[0034] The polypropylene resin (X) according to the present invention may be a propylene homopolymer obtained by homopolymerizing a propylene monomer, or a propylene-α-olefin copolymer obtained by copolymerizing a propylene monomer with an α-olefin comonomer having 2 to 20 carbon atoms other than propylene, such as ethylene and / or 1-butene. The shape of the polypropylene resin (X) is not particularly limited, and it may be in the form of a powder or a particulate product thereof.

[0035] The polypropylene resin (X) according to the present invention may be obtained by mixing other additional components described below as necessary using a Henschel mixer, V blender, ribbon blender, tumbler blender, or the like, and may be kneaded into granules using a kneading machine such as a single-screw extruder, multi-screw extruder, kneader, or Banbury mixer as necessary.

[0036] 1-2. Polypropylene resin (Y) The polypropylene resin (Y) has a property (Y-1).

[0037] 1-2-1. Characteristics (Y-1): MFR (230°C, load 2.16 kgf) is 1g / 10 minutes to 30g / 10 minutes. The MFR of the polypropylene resin (Y) is 1 to 30 g / 10 min, preferably 2 to 25 g / 10 min. When the MFR is 1 g / 10 min or more, the polypropylene resin composition has good fluidity and is less likely to undergo melt fracture during film molding. On the other hand, when the MFR is 30 g / 10 min or less, the polypropylene resin composition has good melt tension, which can reduce neck-in and improve the manufacturing efficiency of the product.

[0038] The MFR of the polypropylene resin (Y) can be easily adjusted by changing the temperature and pressure conditions of the propylene polymerization, or by adding a chain transfer agent such as hydrogen during the polymerization.

[0039] 1-2-2. Manufacturing method of polypropylene resin (Y) There is no limitation on the manufacturing method of polypropylene resin (Y), and it may be one manufactured using a Ziegler-Natta catalyst or a metallocene catalyst. Note that polypropylene resin (Y) does not include those that correspond to polypropylene resin (X). Ziegler-Natta catalysts are catalyst systems such as those outlined in Section 2.3.1 (pp. 20-57) of "Polypropylene Handbook," edited by Edward P. Moore Jr., translated and supervised by Yasuda Tetsuo and Sakuma Nobuo, published by the Industrial Research Institute (1998). Examples of such catalysts include titanium trichloride catalysts consisting of titanium trichloride and organoaluminum halide, magnesium-supported catalysts consisting of a solid catalyst component containing magnesium chloride, titanium halide, and an electron donor compound, an organoaluminum, and an organosilicon compound, and a catalyst in which an organosilicon-treated solid catalyst component formed by contacting a solid catalyst component with an organoaluminum and an organosilicon compound is combined with an organoaluminum compound component.

[0040] The metallocene catalyst is a catalyst consisting of (i) a transition metal compound of Group 4 of the periodic table containing a ligand having a cyclopentadienyl skeleton (a so-called metallocene compound), (ii) a cocatalyst capable of activating the metallocene compound to a stable ionic state by reacting with the metallocene compound, and, if necessary, (iii) an organoaluminum compound, and any known catalyst can be used. The metallocene compound is preferably a bridged metallocene compound capable of stereoregular polymerization of propylene, and more preferably a bridged metallocene compound capable of isoregular polymerization of propylene.

[0041] As the above (i) metallocene compound, for example, those disclosed in JP-A-60-35007, JP-A-61-130314, JP-A-63-295607, JP-A-1-275609, JP-A-2-41303, JP-A-2-131488, JP-A-2-76887, JP-A-3-163088, JP-A-4-300887, JP-A-4-211694, JP-A-5-43616, JP-A-5-209013, JP-A-6-239914, JP-T-H7-504934, and JP-A-8-85708 can be preferably used.

[0042] More specifically, Methylenebis(2-methylindenyl)zirconium dichloride, Ethylenebis(2-methylindenyl)zirconium dichloride, Ethylene 1,2-(4-phenylindenyl)(2-methyl-4-phenyl-4H-azulenyl)zirconium dichloride, Isopropylidene(cyclopentadienyl)(fluorenyl)zirconium dichloride, isopropylidene(4-methylcyclopentadienyl)(3-t-butylindenyl)zirconium dichloride, Dimethylsilylene(2-methyl-4-t-butyl-cyclopentadienyl)(3'-t-butyl-5'-methyl-cyclopentadienyl)zirconium dichloride, Dimethylsilylenebis(indenyl)zirconium dichloride, Dimethylsilylenebis(4,5,6,7-tetrahydroindenyl)zirconium dichloride, Dimethylsilylenebis[1-(2-methyl-4-phenylindenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-ethyl-4-phenylindenyl)]zirconium dichloride, Dimethylsilylenebis[4-(1-phenyl-3-methylindenyl)]zirconium dichloride, Dimethylsilylene(fluorenyl) t-butylamido zirconium dichloride, Methylphenylsilylenebis[1-(2-methyl-4-(1-naphthyl)-indenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-methyl-4,5-benzoindenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-methyl-4-phenyl-4H-azulenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-ethyl-4-(4-chlorophenyl)-4H-azulenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-ethyl-4-naphthyl-4H-azulenyl)]zirconium dichloride, Diphenylsilylenebis[1-(2-methyl-4-(4-chlorophenyl)-4H-azulenyl)]zirconium dichloride, Dimethylsilylenebis[1-(2-ethyl-4-(3-fluorobiphenylyl)-4H-azulenyl)]zirconium dichloride, Dimethylgermylenebis[1-(2-ethyl-4-(4-chlorophenyl)-4H-azulenyl)]zirconium dichloride, Dimethylgermylenebis[1-(2-ethyl-4-phenylindenyl)]zirconium dichloride Examples of zirconium compounds include those mentioned above.

[0043] In the above, compounds in which zirconium is replaced by titanium or hafnium can also be used in the same manner. It is also preferable to use a mixture of a zirconium compound and a hafnium compound. Chloride can also be replaced by other halogen compounds, hydrocarbon groups such as methyl, isobutyl, and benzyl, amide groups such as dimethylamide and diethylamide, alkoxide groups such as methoxy and phenoxy, and hydride groups. Among these, metallocene compounds in which an indenyl group or an azulenyl group is crosslinked with a silicon or germyl group are particularly preferred. The metallocene compound may be supported on an inorganic or organic carrier before use. The carrier is preferably an inorganic or organic porous compound, and specific examples thereof include inorganic compounds such as ion-exchangeable layered silicates, zeolites, SiO2, Al2O3, silica alumina, MgO, ZrO2, TiO2, B2O3, CaO, ZnO, BaO, ThO2, etc., organic compounds such as porous polyolefins, styrene-divinylbenzene copolymers, olefin-acrylic acid copolymers, etc., or mixtures of these.

[0044] Preferred examples of the co-catalyst (ii) capable of reacting with the metallocene compound to activate it to a stable ionic state include organoaluminum oxy-compounds (e.g., aluminoxane compounds), ion-exchangeable layered silicates, Lewis acids, boron-containing compounds, ionic compounds, and fluorine-containing organic compounds.

[0045] Furthermore, preferred examples of the organoaluminum compound (iii) include trialkylaluminums such as triethylaluminum, triisopropylaluminum and triisobutylaluminum, dialkylaluminum halides, alkylaluminum sesquihalides, alkylaluminum dihalides, alkylaluminum hydrides, organoaluminum alkoxides, and the like.

[0046] The method for producing the polypropylene resin (Y) is not particularly limited, and it can be produced by any of the conventionally known methods such as slurry polymerization, bulk polymerization, and gas phase polymerization. Furthermore, within the scope of the invention, it is also possible to produce polypropylene and propylene-based random copolymers by utilizing a multi-stage polymerization method.

[0047] The polypropylene resin (Y) according to the present invention can be obtained by mixing other additional components described below as necessary using a Henschel mixer, a V blender, a ribbon blender, a tumbler blender or the like, and, as necessary, by kneading using a kneader such as a single-screw extruder, a multi-screw extruder, a kneader or a Banbury mixer.

[0048] The polypropylene resin (Y) may be a propylene homopolymer obtained by homopolymerizing a propylene monomer, or a propylene-α-olefin copolymer obtained by copolymerizing a propylene monomer with an α-olefin comonomer having 2 to 20 carbon atoms other than propylene, such as ethylene and / or 1-butene. The polypropylene resin (Y) preferably contains 0 to 6.0 mass% of ethylene as a comonomer, more preferably 0 to 5.0 mass%, and further preferably 0 to 4.0 mass% of ethylene. When the ethylene content is 6.0 mass% or less, the crystallinity is high and the rigidity and heat resistance are high.

[0049] In a preferred embodiment of the polypropylene resin composition for a non-oriented film of the present invention, the polypropylene resin (Y) is a propylene homopolymer. When the polypropylene resin (Y) is a propylene homopolymer, the rigidity is increased. As described above, the polypropylene resin (Y) does not include any polypropylene resin that corresponds to the polypropylene resin (X). However, in a preferred embodiment of the polypropylene resin composition for a non-oriented film of the present invention, the branching index g' of the polypropylene resin (Y) is not in the range of 0.30 or more and less than 0.95.

[0050] The shape of the polypropylene resin (Y) is not particularly limited, and it may be in the form of a powder or a particulate product thereof.

[0051] 1-3. Polypropylene resin composition for non-oriented film 1-3-1. Ratio of polypropylene resin (X) and polypropylene resin (Y) The proportions of the polypropylene resin (X) and the polypropylene resin (Y) in the polypropylene resin composition for non-oriented film of the present invention, based on the total content of (X) and (Y) being 100% by weight, are 1 to 50% by weight for the polypropylene resin (X) and 50 to 99% by weight for the polypropylene resin (Y), preferably 5 to 40% by weight for the polypropylene resin (X) and 60 to 95% by weight for the polypropylene resin (Y), more preferably 8 to 35% by weight for the polypropylene resin (X) and 65 to 92% by weight for the polypropylene resin (Y). By adjusting the content within the above range, a polypropylene resin composition for a non-oriented film having high rigidity and an improved balance between transparency and tear resistance can be obtained.

[0052] The polypropylene resin composition for a non-oriented film of the present invention essentially contains a crystal nucleating agent (A). By containing a crystal nucleating agent, the polypropylene resin composition for a non-oriented film of the present invention has low haze even if it has high rigidity.

[0053] Nucleating agents are classified into organic and inorganic types, and the use of organic nucleating agents is preferred in the present invention, such as sorbitol-based nucleating agents, amide-based nucleating agents, and phosphate-based nucleating agents. The amide-based crystal nucleating agent is a crystal nucleating agent having an amide group. Examples of the amide-based crystal nucleating agent include 1,3,5-tris(2,2-dimethylpropanamido)benzene, N,N',N''-tris(2-methylcyclohexyl)propane-1,2,3-tricarboxamide, N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide, and N,N',N''-tricyclohexyl-trimesic acid amide. Sorbitol-based crystal nucleating agents are crystal nucleating agents that are sorbitol derivatives. Examples of sorbitol-based crystal nucleating agents include 1-[8-propyl-2,6-bis(4-propylphenyl)tetrahydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol, 1,3:2,4-bis-O-(3,4-dimethylbenzylidene)-D-sorbitol, 1-O,3-O:2-O,4-O-bis(4-methylbenzylidene)-D-glucitol and 1,3:2,4-O-bis(4-ethylbenzylidene)-sorbitol. The nucleating agent may be a mixture of a plurality of nucleating agents. The amide-based crystal nucleating agent is preferably used in an amount of 0.01 to 1% by weight, and more preferably 0.01 to 0.03% by weight, based on 100% by weight of (X)+(Y), in order to comply with official regulations and / or to increase rigidity. The sorbitol-based crystal nucleating agent is preferably contained in an amount of 0.01 to 1% by weight, and more preferably 0.1 to 0.6% by weight, based on 100% by weight of the resin composition, in order to comply with official regulations and / or to increase rigidity.

[0054] Examples of the crystal nucleating agent (A) contained in the polypropylene resin composition for non-oriented film of the present invention include sodium 2,4,8,10-tetra-tert-butyl-6-oxo-12H-dibenzo[d,g][1,3,2]dioxaphosphocin-6-olate, zinc stearate, bis(4-tert-butylbenzoato-κO)aluminum hydroxide, 1-[8-propyl-2,6-bis(4-propylphenyl)tetrahydrofuran]-2,4-dihydro-1,2,3,4-tetrahydrofuran, and the like. Examples include hydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol, aluminum bis(4,4',6,6'-tetra-tert-butyl-2,2'-methylenediphenyl phosphate) hydroxide, 1-O,3-O:2-O,4-O-bis(4-methylbenzylidene)-D-glucitol, and N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide.

[0055] The crystal nucleating agent (A) can also be mixed with the polypropylene resin (X) and the polypropylene resin (Y) to prepare a polypropylene resin composition for a non-oriented film. The crystal nucleating agent (A) can be incorporated into a resin and used as a master batch. For example, a master batch containing the crystal nucleating agent (A) can be prepared using one or more of polypropylene resin (X), polypropylene resin (Y), or a resin not corresponding to either polypropylene resin (X) or polypropylene resin (Y), and then mixed with polypropylene resin (X) and polypropylene resin (Y) to prepare a polypropylene resin composition for non-oriented film.

[0056] 1-3-3.Other ingredients The polypropylene resin composition for a non-oriented film of the present invention can be used by adding various components described below, other than the polypropylene resin (X), polypropylene resin (Y) and crystal nucleating agent (A), as necessary.

[0057] 1-3-3-1.Additives Additives such as antioxidants that can be added to propylene-based resins can be appropriately added to the polypropylene resin composition for use in a non-oriented film of the present invention, so long as they do not significantly impair the effects of the present invention. Specifically, phenol-based stabilizers such as 2,6-di-t-butyl-p-cresol (BHT), tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane (manufactured by BASF Japan Ltd., product name "IRGANOX 1010"), and n-octadecyl-3-(4'-hydroxy-3,5'-di-t-butylphenyl)propionate (manufactured by BASF Japan Ltd., product name "IRGANOX 1076"), phosphite-based stabilizers such as bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite and tris(2,4-di-t-butylphenyl)phosphite, lubricants such as higher fatty acid amides and higher fatty acid esters, antistatic agents such as glycerin esters, sorbitan acid esters, and polyethylene glycol esters of fatty acids having 8 to 22 carbon atoms, and antiblocking agents such as silica, calcium carbonate, and talc may be added.

[0058] Also, to impart weather resistance, ultraviolet absorbers and light stabilizers can be added. UV absorbers are compounds that have an absorption band in the UV region, and known types include triazoles, benzophenones, salicylates, cyanoacrylates, nickel chelates, and inorganic fine particles. Of these, the most widely used are triazoles. Hindered amine compounds are commonly used as light stabilizers, and are known as HALS.

[0059] 1-3-3-2.Other polymers To the polypropylene resin composition for a non-oriented film of the present invention, modifiers such as elastomers that can be added to propylene-based resins and polyethylene-based resins can be appropriately added, as long as the effects of the present invention are not impaired. Among the above, examples of the elastomer include ethylene-α-olefin copolymers, binary random copolymer resins of propylene and an α-olefin having 4 to 12 carbon atoms, and ternary random copolymer resins of propylene, ethylene, and an α-olefin having 4 to 12 carbon atoms.

[0060] Furthermore, a styrene-based elastomer can also be added. The styrene-based elastomer can be appropriately selected from commercially available products and used. For example, hydrogenated styrene-butadiene block copolymers are sold under the product name "Kraton G" by Kraton Polymer Japan Co., Ltd. and under the product name "Tuftec" by Asahi Chemicals Co., Ltd., hydrogenated styrene-isoprene block copolymers are sold under the product name "Septon" by Kuraray Co., Ltd., hydrogenated styrene-vinylated polyisoprene block copolymers are sold under the product name "Hybler" by Kuraray Co., Ltd., and hydrogenated styrene-butadiene random copolymers are sold under the product name "Dynaron" by ENEOS Materials Co., Ltd., and an appropriate product may be selected from these product groups and used.

[0061] Examples of polyethylene resins include ethylene / α-olefin copolymers such as high-density polyethylene, low-density polyethylene, and linear low-density polyethylene, and their densities range from 0.860 to 0.964 g / cm. 3 The range of 0.870 to 0.960 g / cm is preferable. 3 More preferably, the density is 0.875 to 0.950 g / cm 3 It is even more preferable that: Within the above range, a film with high transparency can be obtained. The density is a value measured at 23° C. in accordance with JIS K7112. The α-olefin used in the ethylene / α-olefin copolymer is preferably an α-olefin having 3 to 18 carbon atoms. Specific examples include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methyl-pentene-1, 4-methyl-hexene-1, 4,4-dimethylpentene-1, etc. The α-olefin may be one type or a combination of two or more types. Examples of such ethylene / α-olefin copolymers include ethylene-based elastomers, ethylene-propylene-based rubbers, etc. In particular, ethylene / α-olefin copolymers called metallocene-based polyethylenes, which are produced using metallocene-based catalysts with little loss of transparency, are preferred.

[0062] The amount of other polymers such as polyethylene resins when blended is preferably 2 to 30% by weight, more preferably 3 to 25% by weight, and even more preferably 5 to 20% by weight, relative to 100% by weight of the combined total of (X) and (Y).

[0063] The polypropylene resin composition for non-oriented film of the present invention may contain other components as necessary that do not impair the effects of the present invention. Examples of methods for mixing these components include mixing with a Henschel mixer, V blender, ribbon blender, tumbler blender, etc., and melt-kneading with a kneader such as a single-screw extruder, multi-screw extruder, kneader, Banbury mixer, etc., as necessary. There are no particular limitations on the mixing method as long as the effects of the present invention are not impaired in any case.

[0064] 1-4. Film manufacturing The film forming machine used for producing the film is a machine that forms a film by melt extrusion through a T-die, and examples thereof include known T-die film processing devices and known T-die extrusion lamination processing devices, and the like, and the T-die film processing device is preferred. Preferable film forming conditions for the production of the T-die film processing device include a resin temperature of 160 to 260°C and a cooling roll temperature of 20 to 80°C. The obtained T-die film may be a single layer film, or a multilayer film containing at least one layer made of the polypropylene resin composition for non-oriented films. The applications of the film are not particularly limited, and the film can be used, for example, as a film for packaging food such as bread and vegetables, as a film for packaging clothing such as shirts, as a film for packaging industrial parts, as a protective film, synthetic paper, etc. The film can also be used as a substrate for a film laminated to a film such as cellophane, paper, fabric, paperboard, aluminum foil, polyamide resins such as nylon 6 and nylon 66, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, or oriented polypropylene by known techniques such as a dry lamination method or a sand lamination method.

[0065] The method for obtaining the polypropylene resin (X) is not particularly limited, and the polypropylene resin (X) can be produced by the method described above in "1-1-6. Production method of polypropylene resin (X)". The method for obtaining polypropylene resin (Y) is not particularly limited, and it can be produced by the method described above in "1-2-2. Production method of polypropylene resin (Y)". The method for mixing the polypropylene resin (X) and the polypropylene resin (Y) is not particularly limited, and examples of the method include mixing using a Henschel mixer, a V blender, a ribbon blender, a tumbler blender, or the like. The method for melt-kneading the polypropylene resin (X) and the polypropylene resin (Y) is not particularly limited, and examples of the method include a method for melt-kneading using a kneader such as a single-screw extruder, a multi-screw extruder, a kneader, or a Banbury mixer. The ratio of polypropylene resin (X) to polypropylene resin (Y) may be, for example, the ratio described above in "1-3-1. Ratio of polypropylene resin (X) to polypropylene resin (Y)".

[0066] 2. Film The film of the present invention is a non-stretched film comprising at least one layer made of the polypropylene resin composition for a non-stretched film of the present invention, wherein the polypropylene resin composition layer comprises 1 to 50% by weight of polypropylene resin (X) having the above-mentioned properties (X-1) to (X-4), 99 to 50% by weight of polypropylene resin (Y) having the above-mentioned properties, and 0.01 to 1% by weight of a crystal nucleating agent (A) (wherein the total amount of polypropylene resin (X) and polypropylene resin (Y) is 100% by weight).

[0067] The ratio of polypropylene resin (X) to polypropylene resin (Y) may be, for example, the ratio described above in "1-3-1. Ratio of polypropylene resin (X) to polypropylene resin (Y)".

[0068] One aspect of the present invention is a non-stretched film made from the polypropylene resin composition for a non-stretched film of the present invention (hereinafter also referred to as "the non-stretched film of the present invention"). Another embodiment of the present invention is a multilayer film including a layer made of the non-oriented film of the present invention.

[0069] Another embodiment of the present invention is a food packaging film comprising the non-stretched film of the present invention.

[0070] Another embodiment of the present invention is a protective film comprising the unstretched film of the present invention. Another aspect of the present invention is a synthetic paper comprising the unstretched film of the present invention.

[0071] The method for producing the non-stretched film of the present invention is not particularly limited, and the film can be produced by the method described above in "1-4. Production of film." EXAMPLES

[0072] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. The evaluation methods and resins used in the examples and comparative examples are as follows.

[0073] 1. Evaluation method Evaluations were carried out at 20 to 25°C unless otherwise specified. (1)MFR The MFR was measured in accordance with JIS K7210:2014, and the unit of MFR is g / 10 min. (2) Mw / Mn and Mz / Mn Mw / Mn and Mz / Mn were determined by GPC measurement according to the method described above. (3)MT MT was measured using a Capillograph 1B manufactured by Toyo Seiki Seisakusho, according to the method described above. (4) g' g' was determined by GPC equipped with a differential refractometer (RI), a viscosity detector (Viscometer), and a light scattering detector (MALLS) as detectors. (5) mm fraction The mm fraction is calculated according to the method described above. 13 The carbon-carbon valence was determined by C-NMR. A more specific method for determining the mm fraction is described in detail in paragraphs

[0053] to

[0065] of JP 2009-275207 A, and this method was also followed in the present invention. The unit of the mm fraction is %. (6) Melting point The melting point was measured by a differential scanning calorimeter (DSC) by first raising the temperature to 200°C, leaving it for 5 minutes, lowering the temperature to 40°C at a rate of 10°C / min, and then raising the temperature again at a rate of 10°C / min. The melting point was determined as the temperature at the top of the endothermic peak. The unit of the melting point is °C.

[0074] (7) HAZE Haze was measured in accordance with JIS K7136:2000. The smaller the haze value, the better the transparency. Haze is measured in %.

[0075] (8)Young’s modulus The Young's modulus was measured in accordance with JIS K7127-1989 by measuring the tensile modulus (Young's modulus) in the machine direction (MD) of the film under the following conditions. The unit of Young's modulus is MPa. Sample shape: Strip Sample length: 150mm Sample width: 15mm Chuck distance: 100mm Crosshead speed: 1mm / min (9) Flexural modulus The flexural modulus was determined in accordance with JIS K7171:2022 (ISO178). The unit of the flexural modulus is MPa. Sample shape: Strip Sample length: 80mm Sample width: 25mm Bending speed: 2mm / min

[0076] 4.Materials used (1) Polypropylene resin (X) As the polypropylene resin (X1), a propylene homopolymer having a long chain branched structure produced by a macromer copolymerization method, a product name "WAYMAX (registered trademark) MFX3" manufactured by Japan Polypropylene Corporation, was used. 13 The C-NMR and melting point were evaluated. The evaluation results are shown in Table 1. Polypropylene resin (X1) satisfies the requirement (X-3) of log(MT) ≧ -0.9 × log(MFR) + 0.7 (Formula 1). As the polypropylene resin (X2), a propylene homopolymer having a long chain branched structure produced by a macromer copolymerization method, trade name "WAYMAX (registered trademark) MFX6" manufactured by Japan Polypropylene Corporation, was used. 13 The C-NMR and melting point were evaluated. The evaluation results are shown in Table 1. Polypropylene resin (X2) satisfies the requirement (X-3) of log(MT) ≧ -0.9 × log(MFR) + 0.7 (Formula 1).

[0077] [Table 1]

[0078] (2) Polypropylene resin (Y) As the polypropylene resin (Y1), a propylene homopolymer manufactured by Japan Polypropylene Corporation, trade name Novatec PP FB3HBT (melting peak temperature Tm: 164°C, MFR: 10g / 10min, MT: 0.5g) was used. As the polypropylene resin (Y2), a propylene homopolymer manufactured by Japan Polypropylene Corporation, trade name Novatec PP SA03 (melting peak temperature Tm: 164°C, MFR: 30g / 10 min, branching index g' measured by GPC is 0.30 or more and not less than 0.95) As the polypropylene resin (Y3), a propylene homopolymer manufactured by Japan Polypropylene Corporation, trade name Novatec PP FY6H (melting peak temperature Tm: 164°C, MFR: 1.9g / 10 min, branching index g' measured by GPC is 0.30 or more but not less than 0.95) As the polypropylene resin (Y4), a propylene homopolymer manufactured by Japan Polypropylene Corporation, trade name Novatec PP EA6A (melting peak temperature Tm: 167°C, MFR: 1.9g / 10min, MT: 2.7g) was used. As the polypropylene resin (Y5), a propylene homopolymer manufactured by Japan Polypropylene Corporation, trade name Novatec PP FL4 (melting peak temperature Tm: 164°C, MFR: 4g / 10 min, MT: 1.0g)

[0079] (3) Nucleating agent (A) The nucleating agent (A1) was 1-[8-propyl-2,6-bis(4-propylphenyl)tetrahydro[1,3]dioxino[5,4-d][1,3]dioxin-4-yl]ethane-1,2-diol (trade name: Millad NX8000J) manufactured by Milliken Japan LLC. The nucleating agent (A2) was 1,3,5-tris(2,2-dimethylpropanamido)benzene (product name: Irgaclear XT 386) manufactured by BASF Japan Ltd. The nucleating agent (A3) is sodium 2,4,8,10-tetra-tert-butyl-6-oxo-12H-dibenzo[d,g][1,3,2]dioxaphosphocin-6-olate (trade name: Adeka STAB NA-11) manufactured by ADEKA Corporation.

[0080] [Examples 1 to 3] [Comparative Examples 1 to 4] Polypropylene resin (X1) and polypropylene resin (Y) were mixed in the ratio shown in Table 2 using a Henschel mixer, and then melt-extruded at a temperature of 220° C. using an extruder with a screw diameter of 50 mmΦ to form pellets. The obtained pellets were introduced into a single-layer T-die (die width 330 mm, die lip opening 0.8 mm) using a 35 mm diameter extruder set to a resin temperature of 220°C, and melt extruded.The pellets were then cooled and solidified using a #200 matte surface-treated cooling roll adjusted to 30°C and rotating at 20 m / min, to obtain a single-layer unstretched film with a thickness of 30 μm. The physical properties of the resulting pellets and film were measured according to the above-mentioned measuring methods. The evaluation results are shown in Table 2.

[0081] [Table 2]

[0082] The films of Examples 1 to 9 had an excellent balance between rigidity and haze because the polypropylene resin (X) and the polypropylene resin (Y) contained in the polypropylene resin composition satisfied all of the specific physical properties of the present invention. In Comparative Example 1, since the polypropylene resin (X) and the crystal nucleating agent (A1) or (A2) were not contained, the rigidity was insufficient and the haze was also poor. In Comparative Examples 2 and 3, since the crystal nucleating agent (A) was not contained, the haze was also poor. Since the polypropylene resin (X) was not contained in Comparative Example 4, the rigidity was lower than those of Examples 1-3.

[0083] [Examples 10 to 13], [Comparative Examples 5 and 6] Polypropylene resin (X2), polypropylene resin (Y4) and polypropylene resin (Y5) were mixed in the ratios shown in Table 3 using a Henschel mixer, and then the mixture was melt-extruded at a temperature of 220° C. using an extruder having a screw diameter of 50 mmΦ to form pellets. The obtained pellets were introduced into a die (die width 400 mm, die lip opening 0.8 mm) using an extruder with a 40 mm diameter and set to a resin temperature of 250°C, and melt extruded.The pellets were then cooled and solidified using a mirror-finished cooling roll that was adjusted to 40°C and rotated at 3 m / min, obtaining unstretched films with thicknesses of 400 μm and 300 μm. The physical properties of the obtained film were measured according to the above-mentioned measuring methods. The evaluation results are shown in Table 3.

[0084] [Table 3]

[0085] The films of Examples 10 to 13 had an excellent balance between rigidity and haze because the polypropylene resin (X) and the polypropylene resin (Y) contained in the polypropylene resin composition satisfied all of the specific physical properties of the present invention. In Comparative Example 5, since the polypropylene resin (X) and the crystal nucleating agent (A) were not contained, the rigidity was insufficient and the haze was also poor. Comparative Example 6 did not contain the crystal nucleating agent (A), and therefore had poor haze results.

Claims

1. (1) 1 to 50% by weight of a polypropylene resin (X) satisfying the following properties (X-1) to (X-4), (2) 99 to 50% by weight of a polypropylene resin (Y) satisfying the following characteristic (Y-1), and (3) Contains 0.01 to 1% by weight of a crystal nucleating agent (A); Polypropylene resin composition for non-oriented film (wherein the total amount of polypropylene resin (X) and polypropylene resin (Y) is 100% by weight). (X-1) MFR (230° C., load 2.16 kgf) is 0.1 to 30 g / 10 min. (X-2) The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) obtained by GPC is 3.0 to 10.

0. (X-3) The melt tension (MT) (unit: g) measured at 230° C. satisfies the relationship of the following (Equation 1) or (Equation 2). log(MT)+≧-0.9×log(MFR)+0.7 (Formula 1) MT≧15 (Formula 2) (X-4) The branching index g' as measured by GPC is 0.30 or more and less than 0.

95. (Y-1) MFR (230° C., load 2.16 kgf) is 1 to 30 g / 10 min.

2. 2. The polypropylene resin composition for a non-oriented film according to claim 1, wherein the polypropylene resin (Y) is a propylene homopolymer.

3. A non-stretched film comprising the polypropylene resin composition for non-stretched films according to claim 1 or 2.

4. A multilayer film comprising a layer made of the non-oriented film according to claim 3.

5. A food packaging film comprising the non-oriented film according to claim 3.

6. A protective film comprising the unstretched film according to claim 3.

7. A synthetic paper comprising the unstretched film of claim 3.

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