JP5998526B2 - Polypropylene resin composition and film thereof - Google Patents

Description

  The present invention is a polypropylene resin composition, a masterbatch, and a composition for a polypropylene film that can obtain a polypropylene film that is less likely to generate a scum during film formation, has less fish eyes, has good transparency, and is excellent in scratch resistance. And a polypropylene-based film obtained by molding the composition for film and the film composition.

  Polypropylene-based films have properties such as appearance, transparency, mechanical properties, and packaging suitability, so they are widely used in packaging applications such as food packaging and textile packaging. In order to prevent this, it is known that an inorganic fine powder represented by silicon dioxide or an organic fine powder such as a crosslinked polymer is blended in the film as an antiblocking agent.

  Polypropylene particles polymerized with a recently developed highly active polymerization catalyst and a polymerization catalyst whose particle properties have been improved due to loading, etc. have a relatively large average particle size, a small particle size distribution, and a dust explosion. There is an advantage that the risk is low and the handling is easy. As a film with improved blocking resistance using such polypropylene fine particles, for example, Patent Document 1 describes a polypropylene film containing spherical synthetic silica, and Patent Document 2 discloses monodisperse silica and Polypropylene films containing phosphites are described.

JP 2008-208210 A JP 2008-260848 A

However, in the films described in Patent Documents 1 and 2, there is a case where a smear may occur during film formation, and further improvement has been demanded.
An object of the present invention is to provide a polypropylene resin composition, a masterbatch, and a polypropylene system that are capable of obtaining a polypropylene film that does not easily generate scum at the time of film formation, has little fish eye, has good transparency, and has excellent scratch resistance. The object is to provide a film composition and a polypropylene film obtained by molding the film composition.

  As a result of intensive studies, the present inventor has found that the present invention can solve the above problems, and has completed the present invention.

That is, the first of the present invention is expressed by the following formula (1) with respect to polypropylene resin particles (component (A)) having an average particle diameter of 600 to 1500 μm and 100 parts by weight of the component (A). The sphericity is 1.0 to 1.5, the average particle size measured with a Coulter counter is 1.0 to 4.0 μm, the specific surface area is 260 to 1000 m ² / g, and the oil absorption is 100. And 400 ml / 100 g, and a polypropylene resin composition containing 1 to 10 parts by weight of spherical silica fine powder (component (D)) having a pore volume of 0.5 to 1.4 ml / g. .

Sphericality = π × (maximum length of fine powder / 2) ² / (cross-sectional area of fine powder) Formula (1)

  The second of the present invention relates to a master batch obtained by melt-kneading the above polypropylene resin composition.

  The third of the present invention is a polypropylene film composition comprising a polypropylene resin (component (F)) and 0.1 to 20 parts by weight of the masterbatch with respect to 100 parts by weight of the component (F). It is concerned.

The fourth aspect of the present invention relates to a polypropylene film obtained by molding the above polypropylene film composition.
The present invention will be described in detail below.

  According to the present invention, it is possible to obtain a polypropylene-based film that hardly generates scum during film formation, has little fish eye, has good transparency, and has excellent scratch resistance.

The polypropylene resin composition of the present invention has polypropylene resin particles having an average particle diameter of 600 to 1500 μm (hereinafter sometimes referred to as “component (A)”), and 100 parts by weight of the component (A). On the other hand, the sphericity represented by the following formula (1) is 1.0 to 1.5, the average particle size measured with a Coulter counter is 1.0 to 4.0 μm, and the specific surface area is 260. ~1000m a ² / g, oil absorption is 100~400ml / 100g, spherical silica fine powder pore volume is 0.5~1.4ml / g (hereinafter referred to as "component (D)" A polypropylene resin composition containing 1 to 10 parts by weight.

Sphericality = π × (maximum length of fine powder / 2) ² / (cross-sectional area of fine powder) Formula (1)

The polypropylene resin particles (component (A)) used in the present invention have an average particle size of 600 to 1500 μm.
In the polypropylene resin composition of the present invention, from the viewpoint of dispersing the spherical silica fine powder (component (D)), the average particle size is 100 to 600 μm, and the particles having a particle size of 200 μm or less are 20 to 100% by weight. Polypropylene resin particles (hereinafter sometimes referred to as “component (B)”), polypropylene resin particles (component (A)) 20-99 wt%, and polypropylene resin Particles (component (B)) are preferably 80 to 1% by weight (however, the total weight of component (A) and component (B) is 100% by weight), and polypropylene resin particles (component ( A)) 50 to 99% by weight and polypropylene resin particles (component (B)) 50 to 1% by weight (provided that the total weight of component (A) and component (B) is 100% by weight) And more preferable.
The average particle size of the component (A) and the component (B), and the ratio of particles having a particle size of 200 μm or less were determined by using a flow type laser diffraction particle size distribution measuring device (HELOS & GRADIS) manufactured by SYMPATEC, and an integral curve of the weight particle size distribution. It is calculated using.

  The polypropylene resin particles (component (A) and component (B)) used in the present invention are propylene homopolymer, propylene-ethylene random copolymer, propylene-ethylene-α-olefin ternary random copolymer, A polymer component obtained by polymerizing monomers mainly composed of propylene and a copolymer component obtained by polymerizing monomers composed of propylene and ethylene and / or α-olefin having 4 to 12 carbon atoms are at least two or more stages And polypropylene copolymers obtained by multistage production. A propylene homopolymer, a propylene-ethylene random copolymer, or a propylene-ethylene-α-olefin ternary random copolymer is preferable. These may be used alone or in combination of two or more.

Examples of the α-olefin include α-olefins having 4 to 12 carbon atoms, such as 1-butene, 2-methyl-1-propene, 1-pentene, 2-methyl-1-butene, and 3-methyl-1. -Butene, 1-hexene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3 , 3-dimethyl-1-butene, 1-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, di Examples thereof include ethyl-1-butene, 1-nonene, 1-decene, 1-undecene and 1-dodecene. Preferred is 1-butene, 1-pentene, 1-hexene or 1-octene, and more preferred is 1-butene or 1-hexene from the viewpoints of copolymerization properties, economy and the like.
The content of ethylene and / or α-olefin in the copolymer is usually 0.1 to 20% by weight, preferably 1 to 10% by weight.

  According to JIS K7210 of the polypropylene resin particles (component (A) and component (B)) used in the present invention, the melt flow rate (MFR) measured at a temperature of 230 ° C. and a load of 21.18 N is fluid or film-forming. From a viewpoint of manufacture, Preferably, it is 0.1-20 g / 10min, More preferably, it is 1-15g / 10min.

  The polypropylene resin particles (component (A)) used in the present invention can be produced by a conventionally known method. For example, a catalyst system containing Ti, Mg and halogen as essential components, A monomer such as propylene is polymerized by using a catalyst system including an aluminum compound and, if necessary, a third component such as an electron donating compound, a catalyst system containing a metallocene compound and an activation promoter as essential components, and the like. Can be manufactured. Examples of the catalyst system include catalyst systems described in JP-A-61-218606, JP-A-61-287904, JP-A-7-216017, and the like.

The polypropylene resin particles (component (B)) used in the present invention can be produced by, for example, melting and kneading propylene polymer particles (hereinafter, sometimes referred to as “component (E)”) in a polypropylene system. Polymer pellets or molded bodies can be obtained, and then the polypropylene polymer pellets or molded bodies can be pulverized for production. When pulverizing, for example, a spiral mill, a turbo mill, a pin mill, a hammer mill or the like is used. The pulverization is preferably freeze pulverization.
For freeze pulverization, usually, after propylene polymer particles are cooled below the embrittlement point in an atmosphere of liquid nitrogen (about -196 ° C), an impact pulverizer such as a turbo mill, a pin mill, a hammer mill, or a Linlex mill is used. Crush.
As the propylene polymer particles (component (E)), for example, propylene-based polymer particles obtained by the same method as the component (A) can be used.

The spherical silica fine powder (component (D)) used in the present invention has a sphericity represented by the following formula (1) of 1.0 to 1.5, preferably 1.0 to 1.3. is there. If the sphericity exceeds 1.5, it may cause the occurrence of scouring. In the present invention, the sphericity is an average value calculated for 50 or more randomly selected fine particles obtained by performing image processing on a scanning electron micrograph.

Sphericality = π × (maximum length of fine powder / 2) ² / (cross-sectional area of fine powder) Formula (1)

The spherical silica fine powder (component (D)) used in the present invention has an average particle size measured by a Coulter counter of 1.0 to 4.0 μm, preferably 2.0 to 4.0 μm, and more Preferably, it is 3.0-4.0 micrometers.
When the average particle size is less than 1.0 μm, the spherical silica fine powder has poor anti-blocking performance, when the average particle size exceeds 4.0 μm, the transparency of the film is deteriorated, or the films are rubbed with each other May be inferior in scratch resistance.

Spherical silica fine powder used in the present invention (component (D)) has a specific surface area of 260~1000m ² / g, preferably in the 300~1000m ² / g, more preferably, 550~900m ² / g.
When the specific surface area is less than 260 m ² / g, it may cause the generation of fish eyes and squirrels, and when the specific surface area exceeds 1000 m ² / g, it may be inferior in scratch resistance when the films are rubbed. . The specific surface area is determined by the BET method.

The spherical silica fine powder (component (D)) used in the present invention has an oil absorption of 100 to 400 ml / 100 g, preferably 100 to 250 ml / 100 g, more preferably 145 to 200 ml / 100 g. .
When the oil absorption amount is less than 100 ml / g, scratch resistance may be inferior, and when the oil absorption amount exceeds 400 ml / g, fish eyes may be generated. The oil absorption is measured according to JIS K5101.

The fine spherical silica powder (component (D)) used in the present invention has a pore volume of 0.5 to 1.4 ml / g, preferably 0.5 to 1.0 ml / g.
When the pore volume is less than 0.5 ml / g, scratch resistance may be inferior, and when the pore volume exceeds 1.4 ml / g, fish eyes may be generated. The pore volume is determined by the BJH method.

  The compounding amount of the spherical silica fine powder (component (D)) used in the present invention is 1 to 10 parts by weight with respect to 100 parts by weight of the total of component (A) or component (A) and component (B). Yes, when the amount exceeds 10 parts by weight, the fine spherical silica powder aggregates to become fish eyes, and sufficient anti-blocking performance cannot be obtained unless the amount is less than 1 part by weight. From the viewpoint of improving the dispersibility and anti-blocking performance of the spherical silica fine powder, the amount of the spherical silica fine powder (component (D)) is preferably 1 to 7 parts by weight.

  In the polypropylene resin composition of the present invention, a phenolic antioxidant, a phosphorus antioxidant, an acrylate antioxidant, and a neutralizing agent can be blended within a range that does not impair the object and effect of the present invention.

Phenol antioxidants include 2,6-di-t-butyl-4-methylphenol, tetrakis [methylene-3 (3 ′, 5′-di-t-butyl-4-hydroxyphenyl) propionate] methane, octadecyl -3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy } -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5 · 5] undecane, 1,3,5-tris2 [3 (3,5-di-t-butyl-4 -Hydroxyphenyl) poropionyloxy] ethyl isocyanate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 1 3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanate Nurate, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], triethylene glycol-N-bis-3- (3-tert-butyl-5-methyl- 4-hydroxyphenyl) propionate, 1,6-hexanediol bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thiobis-diethylenebis [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2′-methylene-bis- (4-methyl-6-tert-butylphenol), 2,2′-methylene-bis- (4-ethyl-6-tert-butylphenol), 2,2′-methylene-bis- (4-6-di-tert-butylphenol), 2,2′-ethylidene-bis- (4-6-di-t-butylphenol) (cheminox 1129), 2,2'-butylidene-bis- (4-methyl-6-t-butylphenol), 4,4'-butylidene-bis- (3-methyl -6-t-butylphenol), α-tocophenols represented by vitamin E, and the like.
Among the above phenolic antioxidants, tetrakis [methylene-3 (3 ′, 5′-di-t-butyl-4-hydroxyphenyl) propionate] methane, octadecyl-3- (3,5-di-) is preferable. t-butyl-4-hydroxyphenyl) propionate, 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl]- 2,4,8,10-tetraoxaspiro [5.5] undecane, 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, triethylene glycol-N- Bis-3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate, 1,6-hexanediol bis [3- (3,5-di-t-butyl) -4-hydroxyphenyl) propionate], 2,2-thiobis-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], α-tocophenols represented by vitamin E It consists of at least one kind selected from.

  Examples of phosphorus antioxidants include tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (2,4-di-t-). Butylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butyl-6-methylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite Bis (2,4-dicumylphenyl) pentaerythritol diphosphite, tetrakis (2,4-di-t-butylphenyl) -4,4′-diphenylenediphosnite, 2,2′-methylenebis (4,6 -Di-t-butylphenyl) 2-ethylhexyl phosphite, , 2′-ethylidenebis (4,6-di-t-butylphenyl) fluorophosphite, bis (2,4-di-t-butyl-6-methylphenyl) ethyl phosphite, 2- (2,4,4 6-tri-t-butylphenyl) -5-ethyl-5-butyl-1,3,2-oxaphosphorinane, 2,2 ′, 2 ″ -nitrilo [triethyl-tris (3,3 ′, 5, 5'-tetra-t-butyl-1,1'-biphenyl-2,2'-diyl) phosphite and the like.

  Examples of the neutralizing agent include calcium stearate, hydrotalcite, an alkaline earth metal oxide or hydroxide, and the like. These neutralizing agents may be used alone or in combination of at least two kinds.

Examples of the hydrotalcite include anion-exchangeable layered compounds represented by the following general formula (I).
[M ²⁺ 1-XM ³⁺ X (OH) ₂ ] ^{X +} [A ^r ₁₀ x / n · mH ₂ O] ^X- formula (I)
[M ²⁺ 1-XM ³⁺ X (OH) ₂ ] ^{X +} is a basic layer, and [A ^r ₁₀ x / n · mH ₂ O] ^X- is an intermediate layer. M ²⁺ is a cation of a divalent metal such as Mg ²⁺ , Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ²⁺ , Zn ²⁺ , and M ³⁺ is Al ³⁺ , Fe ³⁺ , Cr ³⁺ , Co ³⁺ , It is a cation of a trivalent metal such as In ³⁺ . An ⁻ is OH ⁻ , F ⁻ , Cl ⁻ , Br ⁻ , No ₃ ⁻ , Co ₃ ⁻ , So ₄ ⁻ , Fe (CN) ₆ ³⁻ , CH ₃ COO ⁻ , oxalate ion, salicinate ion, etc. n-valent anion, where n is a positive integer. X is 0 <X ≦ 0.33, and m is a positive integer. The hydrotalcite may be a natural mineral or a synthetic product, and can be used regardless of its crystal structure, crystal particle diameter, water content, surface treatment, and the like. The following hydrotalcite is preferable.
_{Mg 4.5 Al 2 (OH) 13} CO 3 · 3H 2 O
Mg _4.5 Al ₂ (OH) ₁₁ (CO ₃ ) _0.8 · O _{0.2
Mg 4 Al 2 (OH) 12} CO 3 · 3H 2 O
Mg ₅ Al ₂ (OH) ₁₄ CO ₃ .4H ₂ O
Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂ O (natural mineral)
Zn ₄ Al ₂ (OH) ₁₂ CO ₃ .mH ₂ O (m is 0 to 4)
Mg ₃ ZnAl ₂ (OH) ₁₂ CO ₃ · mH ₂ O (m is 0 to 4)

  The alkaline earth metal oxide or hydroxide is an oxide or hydroxide of a metal atom of Group II of the periodic table, and examples thereof include calcium oxide, magnesium oxide, calcium hydroxide, and magnesium hydroxide. It is done. Preferably, it is calcium hydroxide.

  Moreover, you may add another additive and other resin to the polypropylene resin composition of this invention as needed in the range which does not impair the objective and effect of this invention. Other additives include, for example, lubricants represented by 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. Examples thereof include a nucleating agent, an adhesive, an antifogging agent, and an ultraviolet absorber.

  Examples of the other resins include olefin resins and fluorine resins, and examples of the olefin resins include low density polyethylene, high density polyethylene, ethylene-α-olefin copolymer, and polybutene. Examples of the fluorine-based resin include vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene copolymer. These may be manufactured using a heterogeneous catalyst or may be manufactured using a homogeneous catalyst typified by a metallocene catalyst. Also included are styrene copolymer rubbers obtained by hydrogenating styrene-butadiene-styrene copolymers, styrene isoprene-styrene copolymers, and other elastomers.

  The master batch of the present invention is obtained by melt-kneading the above polypropylene resin composition, and comprises component (A) and component (D) or component (A), component (B) and component (D). After mixing, it can be manufactured by melt-kneading, and the mixing method of each component may be arbitrary. From the viewpoint of improving the dispersibility of the spherical silica fine powder, the mixing method is preferably a method in which the component (A) and the component (B) are mixed and then mixed with the component (D) and then melt-kneaded. More preferably, after mixing the component (A) and the component (B), mixing with the component (D) in a powder state, and then melt-kneading.

  The method of mixing in a powder state can be selected from known methods, and examples thereof include a method of mixing using a mixing apparatus such as a Henschel mixer, a super mixer, a tumbler mixer, a screw blender, or a ribbon blender. . From the viewpoint of improving dispersibility, the mixing temperature is preferably 70 to 130 ° C, and more preferably 80 to 120 ° C. Further, from the viewpoint of improving dispersibility, it is preferable to perform mixing by a method in which the peripheral speed of the rotor tip of the mixing apparatus is 5 m / sec or more.

  As a method of melt-kneading, a mixture of component (A) and component (D) or component (A), component (B) and component (D) is melt-kneaded and pelletized using a known granulator. Can do. The granulator used for melt kneading is preferably a high kneading extruder for the purpose of uniformly and finely dispersing the spherical silica fine powder. Examples of the high-kneading extruder include a same-direction rotating biaxial granulator and a different-direction rotating biaxial granulator. Examples of the same-direction rotating biaxial granulator include TEM (registered trademark) manufactured by Toshiba Machine Co., Ltd., TEX (registered trademark) manufactured by Nippon Steel Works, Ltd., and CMP (registered trademark). Examples of the rotating twin-screw granulator include, for example, TEX (registered trademark), CMP (registered trademark) manufactured by Nippon Steel Works, PCM (registered trademark) manufactured by Ikegai Co., Ltd., and LCM manufactured by Kobe Steel Co., Ltd. Registered trademark), FCM (registered trademark), NCM (registered trademark), and the like.

  The composition for polypropylene film of the present invention is 100 parts by weight of polypropylene resin (hereinafter sometimes referred to as “component (F)”) and 100 parts by weight of component (F). The master batch contains 0.1 to 20 parts by weight.

  Examples of the polypropylene resin (component (F)) include propylene homopolymers, propylene-ethylene random copolymers, propylene-ethylene-α-olefin terpolymers having 4 to 12 carbon atoms, propylene- An α-olefin random copolymer having 4 to 12 carbon atoms, a polymer component obtained by polymerizing a monomer mainly composed of propylene, and a monomer comprising propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms Examples thereof include polypropylene copolymers obtained by producing a copolymer component obtained by polymerization in at least two or more stages, preferably propylene homopolymer, propylene-ethylene random copolymer, propylene -Ethylene-C 4-12 α-olefin ternary random copolymer or propylene - a α- olefin random copolymer having 4 to 12 carbon atoms. These may be used alone or in combination of two or more.

  Examples of the α-olefin having 4 to 12 carbon atoms include 1-butene, 2-methyl-1-propene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl-1- Butene, 1-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- For example, 1-butene, 1-pentene, 1-hexene or 1-octene, more preferably copolymerization properties, economy, etc. From the viewpoint of 1-butene or 1-hexene.

  The content of ethylene and / or α-olefin having 4 to 12 carbon atoms in the polypropylene copolymer is usually 0.1 to 20% by weight, preferably 1 to 10% by weight.

  According to JIS K7210 of the polypropylene resin (component (F)) used in the present invention, the melt flow rate (MFR) measured at a temperature of 230 ° C. and a load of 21.18 N is preferable from the viewpoint of fluidity or film formation. Is 0.1 to 20 g / 10 min, more preferably 1 to 15 g / 10 min.

  The polypropylene resin (component (F)) can be produced, for example, by the same method as that for the polypropylene resin particles (component (A)).

  Moreover, you may mix | blend other resin with the composition for polypropylene-type films, and can mention the same thing as what was illustrated above as another resin, for example.

The polypropylene film of the present invention may be a single layer film composed of the composition for polypropylene film of the present invention, and is a laminated film including at least one layer composed of the composition for polypropylene film of the present invention. May be. In the case of a laminated film, the layer made of the polypropylene film composition is preferably formed on the outermost surface of the film.
The preferred thickness of the polypropylene film of the present invention is 10 to 250 μm, and more preferably 30 to 150 μm.

  Examples of the method for producing the polypropylene film of the present invention include a method for forming a film under known molding conditions using a known inflation film production apparatus, T-die film production apparatus, or the like. Among these, a production method using a T-die film production apparatus is preferable.

Examples of known processing conditions when using a T-die film manufacturing apparatus are as follows.
Temperature of molten resin extruded from die lip ... 180-300 ° C
Pruning speed of molten resin at die lip ... 10 to 1500 sec ^-1
Rotating speed of chill roll ... 10 to 500 m / min Temperature of chill roll ... 10 to 80 ° C
Examples of the production method when the polypropylene film of the present invention is a multilayer film include commonly used coextrusion methods, extrusion lamination methods, thermal lamination methods, and dry lamination methods.
The polypropylene film of the present invention can be produced by stretching a film or sheet obtained by molding in advance. Examples of the stretching method include a method of stretching uniaxially or biaxially by a roll stretching method, a tenter stretching method, a tubular stretching method, or the like.

The polypropylene film of the present invention can also be used as a metal-deposited polypropylene film obtained by depositing metal vapor on the film surface.
Examples of the method for producing a metal-deposited polypropylene film include a method in which the polypropylene-based film of the present invention is placed under a high vacuum, and vaporized metal vapor is introduced and deposited on the film surface. Examples of the metal to be deposited include aluminum, titanium, chromium, nickel, copper, germanium, tin, selenium, and the like, and preferably aluminum. The aluminum deposited film is usually 100 to 1000 angstroms, and preferably 300 to 700 angstroms.

Hereinafter, the present invention will be described with reference to examples and comparative examples.
The measured value of each item of an Example and a comparative example was measured with the following method.

(1) Melt flow rate (MFR, unit: g / 10 minutes)
According to JIS K7210, the measurement was performed at a temperature of 230 ° C. and a load of 21.18 N.
(2) Average particle diameter, ratio of particles having a particle diameter of 200 μm or less The average particle diameter of polypropylene resin particles and the ratio of particles having a particle diameter of 200 μm or less are measured by a flow-down laser diffraction particle size distribution analyzer (HELOS & GRADIS, manufactured by SYMPATEC). ) Using an integral curve of the weight particle size distribution.

(3) Fish Eye (FE) Evaluation After film formation using a T-die film forming machine, one film was cut out and the number of all fish eyes seen at 16 cm square (256 cm ² ) was visually measured.

(4) Haze (Unit:%)
It measured according to JIS K7105.

(5) Blocking resistance (unit: kg / 12 cm ² )
Using a 150 mm x 30 mm film (collected so that the film forming direction and the long side direction coincide with each other), the films were overlapped, and a load of 500 g was applied to a range of 40 mm x 30 mm, and the state was maintained at 80 ° C for 24 hours. Adjustments were made. Thereafter, the sample was left in an atmosphere of 23 ° C. and 50% humidity for 30 minutes or more, peeled off at a rate of 200 mm / min using a tensile tester manufactured by Toyo Seiki, and the strength required for peeling the sample was measured.

(6) Evaluation of Meani Using a 90 mmφ extruder and a T-die film processing machine equipped with two 65 mmφ extruders, film formation was carried out continuously for 3 hours, and the state of the adherence to the die lip portion was evaluated. The film forming conditions and the evaluation criteria are as follows.

Molding conditions Filter: Uses a sintered filter with a filtration accuracy of 60 μm.
Extruder set temperature: 260 ° C
Die set temperature: 260 ° C
Die lip gap 0.8mm
Total extrusion rate: 220 kg / hr
Film forming speed: 50 m / min Chill roll temperature: 40 ° C.
Film thickness: 70μm
Meani Evaluation Criteria: The length of the meani attached to the die was measured and evaluated along the film extrusion direction.
5 points ... The situation where there is no mains.
4 points: The average length of the length is less than 0.05 mm.
3 points: The average length of the length is 0.05 to 0.1 mm.
2 points: The average length of the length is 0.1 to 0.2 mm.
1 point: The average length of the length is 0.2 mm or more.

(7) Scratch resistance The films cut out to 5 cm × 5 cm were overlapped and rubbed with the thumb and index finger. The scratch resistance was evaluated by the following formula. The smaller the value, the better the scratch resistance.
ΔHaze (%) = Haze (%) of the film after the test−Haze (%) of the film before the test

  The polypropylene resins used in Examples and Comparative Examples were as follows.

Polypropylene resin (A-1)
Propylene and ethylene random copolymers were polymerized in the gas phase using a Ti-Mg catalyst based Ziegler-Natta catalyst. The obtained resin powder had an ethylene content of 4.0% by weight and an average particle size of 1000 μm.

Polypropylene resin (F-1)
A copolymer of propylene, ethylene and 1-butene was polymerized in a gas phase using a Ti-Mg catalyst based Ziegler-Natta type catalyst. The obtained resin powder had an ethylene content of 2.2% by weight and a butene-1 content of 4.5% by weight.
After 0.13% by weight of Irganox 1010 (manufactured by Ciba Specialty Chemicals Co., Ltd.) was mixed with the above copolymer with a Henschel mixer, it was pelletized by melt extrusion. The obtained pellet had a melt flow rate measured at 230 ° C. of 6.9 g / 10 min.

Polypropylene resin particles (B-1)
A polypropylene resin (F-1) pellet and liquid nitrogen 3.5 times the weight of the polypropylene resin (F-1) were supplied to a Linrex mill manufactured by Hosokawa Micron Co., Ltd. to obtain a frozen and pulverized powder of polypropylene. . The obtained resin powder had an average particle diameter of 350 μm, and particles having a particle size of 200 μm or less were 32% by weight.

The silica fine powder used in Examples and Comparative Examples is as follows.
(1) The shape was specified by observing the fine powder with a scanning electron microscope.
(2) The sphericity was calculated based on a photograph of fine powder taken with a scanning electron microscope.
(3) The average particle size was measured with a Coulter counter.
(4) The oil absorption was measured according to JIS K5101.
(5) The specific surface area was determined by the BET method.
(6) The pore volume was determined by the BJH method.

[Example 1]
Using a 30mmφ different direction biaxial granulator, under the conditions of cylinder set temperature 230 ° C, extrusion rate 20kg / hr, screw rotation speed 300rpm, 100 parts by weight of propylene-ethylene random copolymer particles (A-1) Master containing Fair H31 (manufactured by AGC S-Tech) 2.3% by weight, Irganox 1010 (manufactured by Ciba Specialty Chemicals) 0.15% by weight, Irgafos 168 (manufactured by Ciba Specialty Chemicals) 0.5% by weight Batch pellets were granulated.
Polypropylene resin (F-1) 91.5, the obtained master batch 7.0%, high density polyethylene G1900 (manufactured by Keiyo Polyethylene Co.) 1, 5% were pellet blended, and then 250 ° C. using a 50 mmφ extruder. The mixture was melt-kneaded, extruded from a coat hanger type T die having a discharge amount of 12 kg / hr and a width of 400 mm, and cooled by a chill roll temperature of 30 ° C., a line speed of 18 m / min, and an air chamber cooling method to form a film having a thickness of 30 μm. FE, haze, and blocking of the obtained film were measured.
After pellet blending 91.5% by weight of the polypropylene resin (F-1), 7.0% of the obtained master batch and 1,5% of high-density polyethylene G1900 (manufactured by Keiyo Polyethylene Co., Ltd.), evaluation was performed.

[Example 2]
Using a 30 mmφ different direction biaxial granulator, cylinder setting temperature 230 ° C., extrusion rate 20 kg / hr, screw rotation speed 300 rpm, propylene-ethylene random copolymer particles (A-1) 70% by weight, polypropylene series 100 parts by weight of a polypropylene resin particle composition composed of 30% by weight of resin particles (B-1), 2.3% by weight of Sunsphere L31 (manufactured by AGC S-Tech), Irganox 1010 (manufactured by Ciba Specialty Chemicals) Master batch pellets containing 0.15 wt% and Irgaphos 168 (Ciba Specialty Chemicals) 0.5 wt% were granulated.
The obtained master batch was evaluated in the same manner as in Example 1.

[Comparative Example 1]
In Example 2, the propylene-ethylene random copolymer particles (A-1) were changed to 40% by weight and the polypropylene resin particles (B-1) were changed to 60% by weight, and the Sunsphere L31 was changed to Sunsphere H32 (manufactured by AGC S-Tech Co., Ltd.). Evaluation was carried out in the same manner as in Example 2 except that the change was made to).

[Comparative Example 2]
Evaluation was carried out in the same manner as in Example 2 except that Sunsphere L31 used in Example 2 was changed to Cylisia 420 (manufactured by Fuji Silysia).

[Comparative Example 3]
Evaluation was carried out in the same manner as in Example 2 except that the Sunsphere L31 used in Example 2 was changed to Cyrossphere C-1504 (manufactured by Fuji Silysia).

[Comparative Example 4]
Evaluation was carried out in the same manner as in Example 2 except that Sunsphere L31 used in Example 2 was changed to Mizpearl K-300 (manufactured by Mizusawa Chemical Industry Co., Ltd.).

[Comparative Example 5]
Evaluation was carried out in the same manner as in Example 2 except that Sunsphere L31 used in Example 2 was changed to Shilton JC30 (manufactured by Mizusawa Chemical Industry Co., Ltd.).

Claims (4)

Polypropylene resin particles (component (A)) having an average particle size of 600 to 1500 μm determined using an integral curve of the weight particle size distribution measured with a laser diffraction particle size distribution analyzer, and 100 parts by weight of the component (A) On the other hand, the sphericity represented by the following formula (1) is 1.0 to 1.5, the average particle size measured with a Coulter counter is 1.0 to 4.0 μm, and the specific surface area is 260. ~1000m a ² / g, oil absorption is 100~400ml / 100g, spherical silica fine powder pore volume is 0.5~1.4ml / g (component (D)) and 1 to 10 parts by weight A method for producing a masterbatch for melt-kneading.

Sphericality = π × (maximum length of fine powder / 2) ² / (cross-sectional area of fine powder) Formula (1) Polypropylene resin particles (component (A)) having an average particle size of 600 to 1500 μm determined using an integral curve of the weight particle size distribution measured with a laser diffraction particle size distribution analyzer, and 100 parts by weight of the component (A) On the other hand, the sphericity represented by the following formula (1) is 1.0 to 1.5, the average particle size measured with a Coulter counter is 1.0 to 4.0 μm, and the specific surface area is 260. ~1000m a ² / g, oil absorption is 100~400ml / 100g, spherical silica fine powder pore volume is 0.5~1.4ml / g (component (D)) and 1 to 10 parts by weight Is mixed at 70 to 130 ° C. and then melt-kneaded using a twin screw extruder.

Sphericality = π × (maximum length of fine powder / 2) ² / (cross-sectional area of fine powder) Formula (1) Polypropylene which melt-kneads a polypropylene-based resin (component (F)) and 0.1 to 20 parts by weight of a masterbatch obtained by the method according to claim 1 or 2 with respect to 100 parts by weight of the component (F). For producing a composition for an organic film. A method for producing a polypropylene film, comprising melt-kneading the polypropylene film composition obtained by the method according to claim 3 .