JP2003025425A - Biaxially stretched polypropylene film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biaxially stretched polypropylene film having high rigidity in its longitudinal direction using a widely used longitudinal-lateral sequential biaxial stretching method. SOLUTION: The biaxially stretched polypropylene film comprises polypropylene satisfying formula (1): log (MS)>-0.61 log (MFR)+0.82 or formula (2): log (MS)>-0.61 log (MFR)+0.52 in the relation between melt tension (MS) measured at 230 deg.C and a melt flow rate(MFR) and is mixed with at least one kind of an additive compatible with polypropylene and imparting plasticizing effect at the time of stretching.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a biaxially oriented polypropylene film suitable for a wide range of applications such as packaging and industrial applications.

[0002]

2. Description of the Related Art Due to social demands for reduction of wastes and resources, expectations for thin film materials are increasing, especially for packaging applications. At present, for example, for packaging, a 20 μm biaxially stretched polypropylene film or the like is used, and most of them are manufactured by a general-purpose longitudinal-transverse sequential biaxial stretching method. The general-purpose longitudinal-transverse sequential biaxial stretching method referred to here is an unstretched film obtained by melting a polymer with an extruder and passing through a filtration filter, extruding from a slit-shaped die and winding it around a metal drum and cooling and solidifying it into a sheet. Obtained, the unstretched film is stretched in the longitudinal direction between rolls provided with a peripheral speed difference, then guided to a tenter to be stretched in the width direction, heat-set, and a rolled stretched film is obtained after cooling. Sequential biaxial It is a typical method for producing a stretched polypropylene film.

If the same performance and processability can be obtained with a 15 μm biaxially oriented polypropylene film as the 20 μm biaxially oriented polypropylene film exemplified here, 25% reduction in dust and resources is achieved.

In order to satisfy such requirements, it is first necessary to strengthen the biaxially oriented polypropylene film to suppress the elongation with respect to the tension in the processing step. At this time, since the tension in the processing step is applied in the longitudinal direction of the film, it is necessary to strengthen the biaxially oriented polypropylene film mainly in the longitudinal direction.

Further, generally, by strengthening a polypropylene film, the heat shrinkage rate of the polypropylene film tends to increase. When the dimensional stability of the film at high temperature is deteriorated, the film may shrink during secondary processing such as printing, coating, laminating and the like, and the commercial value of the film may be extremely reduced. Therefore,
It is necessary to suppress the heat shrinkage ratio to be equal to or less than that of a general-purpose biaxially oriented polypropylene film.

Japanese Patent Publication No. 41-21790, Japanese Examined Patent Publication No. 4
According to JP-A 5-37879 and JP-B-49-18628, the biaxially stretched polypropylene film is stretched in the longitudinal direction and the width direction in order to strengthen it, and then re-stretched in the longitudinal direction to be strong in the longitudinal direction. Methods of making films are known. Further, in order to eliminate the weakness in the width direction of the film, which is strong in the longitudinal direction, JP-A-56-56
JP-A-51329 discloses a method in which a polypropylene sheet having a specific melt crystallization temperature is biaxially stretched and then re-stretched in the longitudinal direction.

[0007]

However, it has been difficult to obtain a film strengthened in the longitudinal direction by a general-purpose longitudinal-transverse sequential biaxial stretching method. That is, in the general-purpose longitudinal-transverse sequential biaxial stretching method, it is necessary to bring the temperature into a semi-molten state because the oriented crystal produced in the longitudinal stretching is stretched in the lateral stretching. Therefore, after transverse stretching, most of the crystals rearrange in the width direction,
The resulting biaxially stretched polypropylene film had a rigidity biased in the width direction.

The method of re-stretching in the longitudinal direction as described in Japanese Patent Publication No. 41-21790 and Japanese Patent Laid-Open No. 56-51329 is not only complicated in process and requires a large equipment cost, but also mainly. There is a problem that the heat shrinkage in the longitudinal direction is higher than that of a general-purpose biaxially oriented polypropylene film.

The object of the present invention is to solve the above-mentioned problems, and the general longitudinal-transverse sequential biaxial stretching method provides the film with high rigidity in the longitudinal direction, heat shrinkage ratio, moisture resistance and the like. It is to provide a biaxially oriented polypropylene film which is substantially equal to or less than the biaxially oriented polypropylene film of.

[0010]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above problems can be achieved by the following constitution.

That is, according to the present invention, the relationship between the melt tension (MS) and the melt flow rate (MFR) measured at 230 ° C. is expressed by the following formula (1) log (MS)> − 0.61 log (MFR) +0. 82 A biaxially stretched polypropylene film, which comprises polypropylene that satisfies (1) and is mixed with at least one additive that is compatible with polypropylene and has a plasticizing effect during stretching. In addition, as another configuration, 230
The relationship between the melt tension (MS) and the melt flow rate (MFR) measured at 0 ° C. is polypropylene that satisfies the following formula (2) log (MS)> − 0.61 log (MFR) +0.52 (2): A biaxially stretched polypropylene film comprising one or more additives that are compatible with polypropylene and have a plasticizing effect during stretching. Furthermore, in a preferred embodiment, the additive is a petroleum resin substantially free of polar groups and / or a terpene resin substantially free of polar groups, and the polypropylene has a mesopentad fraction (mmmm) of 90 to 99. 0.5%, and the Young's modulus in the longitudinal direction of the film at 25 ° C. is 2.5 GPa or more,
The m value m = Y (MD) / (Y (MD) + Y (TD)) represented by the Young's modulus (Y (MD)) in the longitudinal direction and the Young's modulus (Y (TD)) in the width direction is 25 ° C. In the range of 0.4 to 0.7,
Further, it is a film having a metal vapor deposition layer provided on at least one side, and has a thickness of 0.05 to 2 on at least one side.
μm polyester urethane resin coating layer,
A biaxially stretched polypropylene film, which is a film in which a metal vapor deposition layer is sequentially provided, and has an adhesive strength of 0.6 N / cm or more between a base layer and a coating layer. Is.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The biaxially oriented polypropylene film of the present invention has a melt tension (M
S) and melt flow rate (MFR) include high melt tension polypropylene satisfying the following formula (1) log (MS)>-0.61 log (MFR) +0.82 (1). Such polypropylene is usually, MS high high melt strength polypropylene (H igh M elt S trength- P
P; hereinafter referred to as HMS-PP).

Here, MS measured at 230 ° C. means that polypropylene is heated to 230 ° C. using a melt tension tester manufactured by Toyo Seiki, and the molten polypropylene is discharged at an extrusion speed of 15 mm / min to form a strand. The tension when the strand was taken out at a speed of 6.5 m / min was measured and designated as MS (unit: cN).

The MFR measured at 230 ° C. is measured under a load of 2.16 kg according to JIS K6758 (unit: g / 10 minutes).

Since the polypropylene resin used in the biaxially oriented polypropylene film of the present invention contains polypropylene satisfying the formula (1), it has been difficult to obtain the longitudinal direction in the general-purpose longitudinal-transverse sequential biaxial stretching method. A biaxially oriented polypropylene film having high rigidity can be produced. That is, the polypropylene satisfying the formula (1) suppresses rearrangement of the longitudinally oriented crystals in the width direction during transverse stretching.

As a method of obtaining polypropylene satisfying the formula (1), a method of blending polypropylene containing a large amount of high molecular weight components, a method of blending an oligomer or a polymer having a branched structure, and JP-A-62-121704 are described. As described above, a method of introducing a long-chain branched structure into a polypropylene molecule, or Japanese Patent No. 2869606.
As described in Japanese Unexamined Patent Publication (Kokai), melt tension and intrinsic viscosity, crystallization temperature and melting point satisfy specific relationships without introducing long chain branching, and the boiling xylene extraction residual ratio is within a specific range. A method of making chain crystalline polypropylene is preferably used.

For the biaxially oriented polypropylene film of the present invention, it is particularly preferable to use HMS-PP in which a long chain branch is introduced into the polypropylene molecule to increase the melt tension. HMS-PP with long chain branching introduced to increase melt tension
Specific examples of HMS-PP manufactured by Basell (type name: PF-814, etc.), H manufactured by Borealis
MS-PP (type name: WB130HMS etc.), Do
HMS-PP (type name: D201, etc.) manufactured by w company is mentioned.

As an index value showing the degree of long chain branching of polypropylene, there is a branching index g represented by the following formula.

G = [η]_LB/ [Η]_Lin Where [η]_LBOf polypropylene with long chain branch
Intrinsic viscosity, [η] _LinIs a polyp with long chain branching
Straight chain having substantially the same weight average molecular weight as ropylene
It is the intrinsic viscosity of crystalline polypropylene. Shown here
Intrinsic viscosity was measured by a known method using a sample dissolved in tetralin.
At 135 ° C. Further, the weight average molecular weight is M.
L. McConnell by American L
Laboratory, May, 63-75 (1978)
The method described in, ie low angle laser light scattering
It is measured by a photometric method.

The branching index g of the polypropylene satisfying the formula (1) contained in the biaxially oriented polypropylene film of the present invention is preferably 0.95 or less, more preferably 0.9 or less. If the branching index exceeds 0.95, the effect of adding polypropylene satisfying the formula (1) may decrease, and the Young's modulus in the longitudinal direction of the film may become insufficient.

The melt tension (MS) of polypropylene satisfying the formula (1) contained in the biaxially oriented polypropylene film of the present invention is preferably in the range of 3 to 100 cN. If the MS is less than 3 cN, the Young's modulus in the longitudinal direction of the film may be insufficient. The larger the MS, the higher the Young's modulus in the longitudinal direction, but if the MS exceeds 100 cN, the film formability may deteriorate. MS of polypropylene satisfying the formula (1) is more preferably 4 to 80 cN, further preferably 5 to 40.
cN, most preferably 5 to 20 cN.

The amount of polypropylene satisfying the formula (1) contained in the biaxially oriented polypropylene film of the present invention is not particularly limited, but is preferably 1 to 60% by weight, and addition of a small amount is effective. Is a feature. If the mixing amount is less than 1% by weight, the effect of improving the rigidity in the longitudinal direction may be reduced, and if it exceeds 60% by weight, the longitudinal stretchability may be deteriorated, and the impact resistance and haze of the film may be deteriorated. . The mixing amount of polypropylene satisfying the formula (1) is more preferably 2 to 50% by weight, further preferably 3 to 40% by weight.

Another constitution of the present invention is that the relationship between the melt tension (MS) and the melt flow rate (MFR) of the polypropylene used in the present invention satisfies the following expression (2). log (MS)>-0.61 log (MFR) +0.52 (2) The polypropylene used for the biaxially oriented polypropylene film of the present invention is made of polypropylene satisfying the formula (2), and thus has a general-purpose longitudinal-transverse sequential two In the axial stretching method,
It is possible to produce a biaxially oriented polypropylene film having high rigidity in the longitudinal direction, which has been difficult until now.

The polypropylene used in the present invention more preferably satisfies the formula (2 '), particularly preferably the formula (2''). These are, for example, HMS-PP.
Can be prepared by adjusting the addition amount of, and the rigidity in the longitudinal direction can be further improved.

Log (MS)> − 0.61 log (MFR) +0.56 (2 ′) log (MS)> − 0.61 log (MFR) +0.62 (2 ″) Polypropylene satisfying the above formula (2) Is a mixture of so-called high melt strength polypropylene (High Melt Strength-PP; hereinafter referred to as HMS-PP) and general-purpose polypropylene having a high melt tension (MS), or a long-chain branched component in the main chain skeleton of the general-purpose polypropylene. Is introduced by copolymerization, graft polymerization or the like to increase the melt tension of polypropylene. By mixing such HMS-PP, rearrangement of the longitudinally oriented crystals in the width direction during transverse stretching can be suppressed.

The melt flow rate (MFR) of polypropylene used for the biaxially oriented polypropylene film of the present invention is preferably in the range of 1 to 30 g / 10 minutes from the viewpoint of film forming property. If the MFR is less than 1 g / 10 minutes, problems such as an increase in filtration pressure during melt extrusion and a long time required to replace the extrusion raw material may occur. If the MFR exceeds 30 g / 10 minutes, problems such as large thickness unevenness of the formed film may occur. The MFR is more preferably 1 to 20 g / 10 minutes.

Mesopentad fraction of polypropylene used for the biaxially oriented polypropylene film of the present invention (mmm
m) is preferably 90 to 99.5%, and 94
More preferably, it is ˜99.5%. Where mm
mm is an index that directly reflects the isotactic three-dimensional structure of polypropylene. mmmm to 90
By setting it to 99.5%, it is possible to stably manufacture a film having excellent dimensional stability and significantly improved heat resistance, rigidity, moisture resistance, chemical resistance, etc., and thus printing, coating, vapor deposition, and bag making. It is possible to provide a film having high secondary processability in a film processing step such as laminating. When mmmm is less than 90%, the rigidity when formed into a film tends to decrease and the heat shrinkage tends to increase, so that the secondary processability such as printing, coating, vapor deposition, bag making and laminating process deteriorates. In some cases, the water vapor transmission rate may be high. mmmm is 9
If it exceeds 9.5%, the film-forming property may deteriorate. m
The mmm is more preferably 95 to 99%, most preferably 96 to 98.5%.

The isotactic index (II) of polypropylene used for the biaxially oriented polypropylene film of the present invention is preferably in the range of 92 to 99.8%. When II is less than 92%, problems such as a decrease in stiffness when formed into a film, an increase in heat shrinkage, and deterioration in moisture resistance may occur. Further, when II exceeds 99.8%, the film forming property may deteriorate.
II is more preferably 94 to 99.5%.

The polypropylene used for the biaxially stretched polypropylene film of the present invention is a waste film produced during the production of the biaxially stretched polypropylene film of the present invention, from the viewpoint of economy, etc., within a range not impairing the characteristics of the present invention. Or
A waste film produced during the production of other films and other resins may be blended and used.

The polypropylene used in the biaxially oriented polypropylene film of the present invention is mainly composed of a homopolymer of propylene, and is copolymerized with other unsaturated hydrocarbon monomer components within a range not impairing the object of the present invention. Other polymers may be used, or a polymer obtained by copolymerizing propylene and a monomer component other than propylene may be blended. Examples of such a copolymerization component or a monomer component constituting the blend include ethylene, propylene (in the case of a copolymerized blend), 1-butene, 1-pentene, 3-
Methylpentene-1,3-methylbutene-1,1-hexene, 4-methylpentene-1,5-ethylhexene-
1,1-octene, 1-decene, 1-dodecene, vinylcyclohexene, styrene, allylbenzene, cyclopentene, norbornene, 5-methyl-2-norbornene and the like can be mentioned.

Here, the above-mentioned melt tension (MS), melt flow rate (MFR), g value, mesopentad fraction (mmmm), isotactic index (II).
It is desirable to determine the characteristic values of polypropylene such as by using raw material chips before film formation, but after film formation, the film is extracted with n-heptane at a temperature of 60 ° C or less for about 2 hours to remove impurities and additives. It is also possible to measure by using a sample obtained by vacuum-drying at 130 ° C. for 2 hours or more after removing.

Next, the biaxially stretched polypropylene film of the present invention is mixed with at least one additive which is compatible with polypropylene and has a plasticizing effect during stretching from the viewpoint of strengthening and film-forming property. To be done. The additive capable of having the plasticizing effect here means a plasticizer which enables stable high-stretching. If such an additive is not mixed, the object of the present invention cannot be fully exerted and the film-forming property will be poor. As such an additive, at least one kind of a petroleum resin that does not substantially contain a polar group and / or a terpene resin that does not substantially contain a polar group is preferably used from the viewpoint of high-magnification stretching and improvement of barrier properties.

Here, the petroleum resin which does not substantially contain a polar group is a petroleum resin having no polar group consisting of a hydroxyl group, a carboxyl group, a halogen group, a sulfone group, or a modified product thereof. Is a resin whose main raw material is cyclopentadiene-based hydrocarbon derived from petroleum-based unsaturated hydrocarbon or higher olefin-based hydrocarbon.

Further, the glass transition temperature (hereinafter sometimes abbreviated as Tg) of the petroleum resin which does not substantially contain such a polar group is preferably 60 ° C. or higher. Tg is 60
If the temperature is lower than 0 ° C, the effect of improving the rigidity may be reduced.

Further, a hydrogenated (hereinafter sometimes abbreviated as hydrogenated) petroleum resin obtained by adding hydrogen to such a petroleum resin and having a hydrogenation rate of 90% or more, preferably 99% or more is particularly preferably used. To be Typical hydrogenated petroleum resins include, for example, alicyclic petroleum resins such as polydicyclopentadiene having a Tg of 70 ° C. or higher and a hydrogenation rate of 99% or higher.

The terpene resin which does not substantially contain a polar group is a terpene resin having no polar group consisting of a hydroxyl group, an aldehyde group, a ketone group, a carboxyl group, a halogen group, a sulfone group or a modified product thereof. , Ie (C
₅ H ₈ ) n hydrocarbons and modified compounds derived therefrom. Here, n is a natural number of 2 to 20.

The terpene resin is sometimes called a terpenoid, and typical compounds include pinene, dipentene, carene, myrcene, ocimene, limonene, terepinolene, terpinene, sabinene, tricyclene, bisabolen, zingiperene, santalen, camphorene, myren,
In the case of the biaxially oriented polypropylene film of the present invention, such as totalene, hydrogen is added and the hydrogenation rate is 90%.
It is preferable that the content is not less than the above, and particularly preferably 99% or more. Among them, hydrogenated β-pinene and hydrogenated β-dipentene are particularly preferably used.

The bromine number of the petroleum resin or terpene resin is preferably 10 or less, more preferably 5 or less, and particularly preferably 1 or less.

The additive may be added in such an amount that the plasticizing effect is exerted, but it is preferably 0.1 to 30% by weight in total including the petroleum resin and the terpene resin. When the amount of the resin mixed is less than 0.1% by weight, stretchability,
In some cases, the effect of improving the rigidity in the longitudinal direction may be reduced, or the transparency may be deteriorated. On the other hand, if it exceeds 30% by weight, the thermal dimensional stability may be deteriorated, or the additive may bleed out to the film surface layer to deteriorate the slipperiness. The amount of the additive mixed is more preferably 1 to 20% by weight, and further preferably 2 to 15% by weight, including the amounts of the petroleum resin and the terpene resin added.

When a petroleum resin containing a polar group and / or a terpene resin is used as an additive,
Since it has poor compatibility with polypropylene, voids are likely to be formed inside the film, the water vapor transmission rate becomes high, and the bleed-out of the antistatic agent and the lubricant may be deteriorated.

Specific examples of the additive that is compatible with polypropylene and has a plasticizing effect during stretching include, for example, "ESCOLETS" (type name: E manufactured by Tonex Co., Ltd.).
5300 series), Yasuhara Chemical Co., Ltd. "Clearon" (type name: P-125 etc.), Arakawa Chemical Industry Co., Ltd. "Arcon" (type name: P-125 etc.) and the like.

The biaxially oriented polypropylene film of the fifth aspect of the present invention can be made into a metal vapor deposition film having a high gas barrier property by providing a metal vapor deposition layer on at least one surface.

In addition, the biaxially stretched polypropylene film of the present invention is provided with a coating layer of a polyester urethane resin and a metal vapor deposition layer on at least one surface, so that the metal vapor deposition has a higher gas barrier property than the above metal vapor deposition film. It can be a film.

In order to obtain an excellent gas barrier property after metal deposition, the coating layer is coated with a mixed coating agent of a water-soluble and / or water-dispersible crosslinked polyester urethane resin and a water-soluble organic solvent. Preferably, it is formed by drying.

The polyester urethane resin used for the coating layer comprises a polyester polyol obtained by esterifying a dicarboxylic acid and a diol component, a polyisocyanate, and optionally a chain extender.

The dicarboxylic acid component of the polyester urethane resin used for the coating layer includes terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid,
Trimethyladipic acid, sebacic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, pimelic acid,
2,2-Dimethylglutaric acid, azelaic acid, fumaric acid, maleic acid, itaconic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4- Naphthalic acid, diphenic acid, 4,4'-oxybenzoic acid,
2,5-naphthalenedicarboxylic acid and the like can be used.

The diol component of the polyester urethane resin used for the coating layer is ethylene glycol, 1,4-
Examples thereof include aliphatic glycols such as butanediol, diethylene glycol and triethylene glycol, aromatic diols such as 1,4-cyclohexanedimethanol, and poly (oxyalkylene) glycols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol.

The polyester urethane resin used for the coating layer is a p-type resin in addition to the dicarboxylic acid component and the diol component.
An oxycarboxylic acid such as oxybenzoic acid may be copolymerized, and further, these have a linear structure,
A branched polyester can be prepared by using an ester-forming component having a valence of 3 or more.

Examples of the polyisocyanate include hexamethylene diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, isophorone diisocyanate, tetramethylene diisocyanate, xylylene diisocyanate, lysine diisocyanate, an addition product of tolylene diisocyanate and trimethylolpropane, hexamethylene diisocyanate and trimethylol. Examples thereof include ethane adducts.

As the chain extender, pendant carboxyl group-containing diols such as ethylene glycol, diethylene glycol, propylene glycol,
1,4-butanediol, hexamethylene glycol,
Glycols such as neopentyl glycol, or ethylenediamine, propylenediamine, hexamethylenediamine, phenylenediamine, tolylenediamine,
Examples thereof include diphenyls such as diphenyldiamine, diaminodiphenylmethane, diaminodiphenylmethane, and diaminocyclohexylmethane.

Specific examples of the polyester urethane type resin include "HYDRAN" (type name: AP-40F, etc.) manufactured by Dainippon Ink and Chemicals, Inc.

When the coating layer is formed, N-methylpyrrolidone, which is a water-soluble organic solvent for the coating agent, is used in order to improve the coating formability of the coating layer and the adhesiveness with the base layer.
It is preferable to add at least one kind of ethyl cellosolve acetate and dimethylformamide. Especially N
-Methylpyrrolidone is preferable because it has a large effect of improving the film formability and the adhesion to the substrate. The amount of addition is preferably 1 to 15 parts by weight with respect to 100 parts by weight of the polyester urethane resin from the viewpoint of preventing flammability and odor deterioration of the coating agent,
More preferably, it is 3 to 10 parts by weight.

Furthermore, it is preferable to introduce a cross-linking structure into the water-dispersible polyester urethane resin to enhance the adhesiveness between the coating layer and the base layer. As a method for obtaining such a coating liquid, JP-A-63-15816 and JP-A-63-25 are known.
The methods disclosed in Japanese Patent No. 6651 and Japanese Patent Application Laid-Open No. 5-152159 can be mentioned. As the crosslinkable component, it is possible to add at least one crosslinker selected from an isocyanate compound, an epoxy compound, and an amine compound.
These cross-linking agents cross-link with the above-mentioned polyester urethane resin to enhance the adhesiveness between the base layer and the metal vapor deposition film.

Examples of the isocyanate compound used as the crosslinking agent include, but are not limited to, the above-mentioned toluene diisocyanate, xylene diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

Examples of the epoxy compound used as the crosslinking agent include diglycidyl ether of bisphenol A and its oligomer, diglycidyl ether of hydrogenated bisphenol A and its oligomer, orthophthalic acid diglycidyl ether, and isophthalic acid diglycidyl ether. , Terephthalic acid diglycidyl ether,
Examples include adipic acid diglycidyl ether,
It is not limited to this.

Examples of the amine compound used as the cross-linking agent include amine compounds such as melamine, urea and benzoguanamine, and amino resins obtained by addition-condensing formaldehyde and an alcohol having 1 to 6 carbon atoms with the above amino compound, hexamethylene. Examples include, but are not limited to, diamine and triethanolamine.

From the viewpoints of food hygiene and adhesiveness to the substrate, it is preferable to add an amine compound to the coating layer. Specific examples of the amine compound used as the cross-linking agent include "Beckamine" manufactured by Dainippon Ink and Chemicals, Inc.
(Type name: APM, etc.) and the like.

The amount of the crosslinking agent selected from an isocyanate compound, an epoxy compound and an amine compound is
From the viewpoint of improving chemical resistance and preventing deterioration of water resistance, 1 to 15 parts by weight is preferable, and more preferably 3 to 10 parts by weight, based on 100 parts by weight of the mixed coating material of the water-soluble polyester urethane resin and the water-soluble organic solvent. is there. If the addition amount of the cross-linking agent is less than the above range, the effect of improving the adhesiveness may not be obtained, and if it exceeds 15 parts by weight, it is presumed to be due to the cross-linking agent remaining unreacted, There may be a decrease in the adhesiveness of the base layer.

In addition, a small amount of a crosslinking accelerator may be added to the coating layer so that the coating layer composition described above is completely crosslinked and cured within the time for forming the metal vapor deposition film.

As the crosslinking accelerator added to the coating layer, a water-soluble acidic compound is preferable because it has a large effect of promoting crosslinking. Examples of the crosslinking accelerator include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, adipic acid, trimethyladipic acid, sebacic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, sulfonic acid, pimelic acid. 2,2-dimethylglutaric acid, azelaic acid, fumaric acid, maleic acid, itaconic acid, 1,
3-Cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-naphthalic acid, diphenic acid, 4,4′-oxybenzoic acid, 2,5-naphthalenedicarboxylic acid, etc. Can be used.

Specific examples of these crosslinking accelerators include "Catalyst" (type name: PTS, etc.) manufactured by Dainippon Ink and Chemicals, Inc.

Further, inert particles may be added to the coating layer, and examples of the inert particles include inorganic fillers such as silica, alumina, calcium carbonate, barium sulfate, magnesium oxide, zinc oxide and titanium oxide. In addition, examples thereof include organic polymer particles such as crosslinked polystyrene particles, crosslinked acrylic particles, and crosslinked silicon particles. Also,
In addition to the inert particles, wax-based lubricants and mixtures thereof may be added.

The coating layer has a thickness of 0.
It is preferably provided with a thickness of 05 to 2 μm. If the coating layer is thinner than 0.05 μm, the adhesiveness to the base layer may be deteriorated to cause fine film omission, and the gas barrier performance after metal deposition may be deteriorated. When the coating layer is thicker than 2 μm, it takes a long time to cure the coating layer, the above-mentioned crosslinking reaction may be incomplete and the gas barrier performance may be deteriorated, and the coating layer may be formed on the base layer during the film forming process. When it is provided, the recoverability of the film scraps to the base layer may be deteriorated, and many internal voids having the coating layer resin as a core may be formed, resulting in deterioration of mechanical properties.

The adhesive strength between the coating layer and the base layer is 0.
It is preferably 6 N / cm or more. When the adhesive strength between the coating layer and the base layer is less than 0.6 N / cm, the coating layer is likely to be peeled off in the processing step, which may increase the limitation in use. The adhesive strength between the coating layer and the base layer is preferably 0.8 N / cm or more, more preferably 1.0 N / cm or more.

When a coating layer is provided on at least one side of the biaxially stretched polypropylene film of the present invention to be used as a metal vapor deposition film, the centerline average roughness (Ra) of the biaxially stretched polypropylene film of the present invention is easy to handle. From the viewpoint of slipperiness, blocking resistance, and 0.01 to 0.
5 μm is preferable, more preferably 0.02 to 0.2 μm
Is. When the center line average roughness (Ra) is less than 0.02 μm, the slipperiness of the film may be deteriorated and the handling property may be lowered, and the center line average roughness (Ra) is 0.2.
When the thickness exceeds μm, when the metal vapor deposition film is formed by sequentially forming the coating layer and the metal vapor deposition layer, pin holes or the like may occur in the aluminum film and the gas barrier property may be deteriorated.

When a coating layer is provided on at least one side of the biaxially oriented polypropylene film of the present invention and is used as a metal vapor deposition film, the surface gloss of the biaxially oriented polypropylene film of the present invention is that of the metallic luster after vapor deposition. For beauty, 135% or more is preferable, and 1 is more preferable.
It is 38% or more.

Further, in the present invention, the method of applying the coating liquid is a method of applying the coating liquid outside the polypropylene film manufacturing process using a reverse roll coater, a gravure coater, a rod coater, an air doctor coater or a coating device other than these. Is preferred. More preferably, as a method of applying in the film manufacturing process, a coating solution is applied to a polypropylene unstretched film,
There are a method of sequentially biaxially stretching, a method of coating on a uniaxially stretched polypropylene film, and a method of further stretching in a direction perpendicular to the uniaxially stretching direction. Of these methods, the method of applying to a uniaxially stretched polypropylene film and further stretching in a direction perpendicular to the uniaxially stretched direction is most preferable because the coating layer has a uniform thickness and the productivity is improved.

When the biaxially oriented polypropylene film of the present invention is used as a metal vapor deposition film, it is better not to add an organic lubricant such as fatty acid amide to the polypropylene of the base layer because of the adhesiveness of the coating layer and the metal vapor deposition layer. Suitable for However, it is acceptable to add a small amount of organic crosslinkable particles or inorganic particles in order to impart slipperiness and improve workability and winding property. Examples of the organic crosslinkable particles added to the base layer polypropylene in a small amount include crosslinked silicone particles, crosslinked polymethylmethacrylate particles, and crosslinked polystyrene particles. Examples of the inorganic particles include zeolite, calcium carbonate, silicon oxide, and aluminum silicate. can do. The average particle size of these particles is preferably 0.5 to 5 μm, because slipperiness can be imparted without significantly deteriorating the transparency of the film of the present invention.

An antistatic agent is preferably added to the biaxially stretched polypropylene film of the present invention except for the case where it is used as a metal vapor deposition film having the above-mentioned constitution, in order to prevent electrostatic damage due to film charging. The antistatic agent contained in the biaxially stretched polypropylene film of the present invention is not particularly limited, but for example, ethylene oxide adduct of betaine derivative, quaternary amine compound, alkyldiethanolamine fatty acid ester, glycerin fatty acid ester,
Mention may be made of stearic acid glycerides and the like, or mixtures thereof.

Further, a lubricant is preferably added to the biaxially oriented polypropylene film of the present invention, and it is more preferably used in combination with the antistatic agent, except when it is used as a metal vapor deposition film having the above-mentioned constitution. This is JIS
Flowability of thermoplastic resin expressed in terms during heat molding,
It is added to improve the releasability, and is added to adjust the frictional force between the processing machine and the film surface or between the films.

The lubricant added to the biaxially oriented polypropylene film of the present invention is not particularly limited, and examples thereof include stearic acid amide, erucic acid amide, erucic acid amide,
Examples thereof include amide compounds such as oleic acid amide, and the like, or a mixture thereof.

The amount of the antistatic agent added to the biaxially oriented polypropylene film of the present invention is preferably 0.3 parts by weight or more, more preferably 100 parts by weight of the polypropylene resin used. 0.4 ~
It is in the range of 1.5 parts by weight. Further, the total addition amount of the antistatic agent and the lubricant is preferably 0.5 to 2.0 parts by weight in terms of antistatic property and slipperiness.

Further, inorganic particles and / or crosslinked organic particles are preferably added and mixed to the biaxially stretched polypropylene film of the present invention in order to impart slipperiness.

In the present invention, the term “inorganic particles” refers to inorganic particles of a metal compound and is not particularly limited, and examples thereof include zeolite, calcium carbonate, magnesium carbonate, alumina, silica, aluminum silicate, kaolin, kaolinite, talc, clay, Examples thereof include particles of diatomaceous earth, montmorillonite, titanium oxide, and the like, or a mixture thereof.

In the present invention, the crosslinked organic particles are particles obtained by crosslinking a polymer compound with a crosslinking agent. The crosslinked organic particles added to the biaxially stretched polypropylene film of the present invention are not particularly limited, for example, crosslinked particles of polymethoxysilane compound, crosslinked particles of polystyrene compound, crosslinked particles of acrylic compound, polyurethane compound. Examples thereof include crosslinked particles of, polyester-based compound crosslinked particles, fluorine-based compound crosslinked particles, or a mixture thereof.

The average particle size of the inorganic particles and the crosslinked organic particles is preferably in the range of 0.5 to 6 μm. The average particle size is 0.
If it is less than 5 μm, the slipperiness may be deteriorated, and if it exceeds 6 μm, particles may come off or the film surface may be easily scratched when the films are rubbed with each other.

The addition amount of the inorganic particles and / or the crosslinked organic particles is preferably in the range of 0.02% by weight to 0.5% by weight, more preferably 0.05% by weight to 0.2%.
It is preferably in the range of wt% in terms of antiblocking property, slipperiness and transparency.

If necessary, the biaxially oriented polypropylene film of the present invention may contain a nucleating agent, a heat stabilizer, an antioxidant and the like other than the above.

For example, as the nucleating agent, a sorbitol-based agent,
0.5% by weight or less of an organic phosphoric acid ester metal salt type, an organic carboxylic acid metal salt type, a rosin type nucleating agent and the like, and 2,6-di-tert-butyl-4-methylphenol as a heat stabilizer. 0.5% by weight or less of (BHT) and tetrakis- (methylene- (3,5-di-third-
Butyl-4-hydroxy-hydrocinname
G)) butane (Irganox 1010) and the like.
You may add in the range of 5 weight% or less.

Next, on at least one side of the biaxially stretched polypropylene film of the present invention, additives bleed-out / scattering suppression, vapor deposition film easy adhesion, easy printability, heat sealability imparting, and printing are also applied for purposes other than the above. Known polyolefin resins are preferably laminated according to various purposes such as imparting laminating property, imparting gloss, reducing haze (imparting transparency), imparting releasability and imparting slipperiness.

At this time, the laminated thickness is preferably 0.25 μm or more and 1/2 or less of the total thickness of the film. If the layer thickness is less than 0.25 μm, uniform layering becomes difficult due to film breakage, etc.
If it exceeds, the influence of the surface layer on the mechanical properties becomes large, the Young's modulus decreases, and the tensile strength of the film also decreases. Further, the surface layer resin to be laminated at this time does not necessarily have to satisfy the scope of the present invention, and the lamination method includes coextrusion, in-line / off-line extrusion lamination, in-line / off-line coating, etc. However, the best method may be selected at any time.

By subjecting at least one film surface of the biaxially stretched polypropylene film of the present invention to corona discharge treatment so that the wetting tension of the film surface is 35 mN / m or more, printability, adhesiveness, antistatic property and lubricant can be obtained. Can be preferably used in order to improve the bleed-out property. Atmosphere gas during corona discharge treatment is air,
Oxygen, nitrogen, carbon dioxide gas, or a mixed system of nitrogen / carbon dioxide gas is preferable, and from the viewpoint of economy, corona discharge treatment in air is particularly preferable.

The Young's modulus (Y (MD)) in the longitudinal direction at 25 ° C. of the biaxially oriented polypropylene film of the present invention is 2.
It is preferably at least 5 GPa. Y (M
When D) is less than 2.5 GPa, the rigidity in the width direction becomes higher than that in the longitudinal direction, and the rigidity becomes unbalanced. For this reason, the stiffness of the film may be insufficient, pitch deviation during printing, stretching of the film during lamination,
When a film coated or vapor-deposited is used, the film may be cracked and the tensile strength of the film may be insufficient. Y (MD) at 25 ° C. is the cooling drum temperature when cooling and solidifying from a molten state to obtain an unstretched sheet, the longitudinal stretching conditions (temperature, magnification, etc.), the crystallinity of the polypropylene used (mesopentad fraction (mmmm)). , The isotactic index (II), etc.), and the amount of additives that can have a plasticizing effect during stretching, and the like, and the optimum film forming conditions can be controlled as long as the characteristics of the present invention are not impaired.・ Select raw materials. Y at 25 ° C
(MD) is more preferably 2.7 GPa or more, further preferably 3.0 GPa or more, and most preferably 3.2 Gpa.
Pa or higher.

The Young's modulus (Y (MD)) in the longitudinal direction at 80 ° C. of the biaxially oriented polypropylene film of the present invention is
It is preferably 0.4 GPa or more. Y at 80 ° C
If the (MD) is less than 0.4 GPa, the tensile strength may be insufficient during film processing. Y at 80 ° C
(MD) is the temperature of the cooling drum when cooling and solidifying from the molten state to obtain an unstretched sheet, the longitudinal stretching conditions (temperature, magnification, etc.), the crystallinity of the polypropylene used (mesopentad fraction (mmmm), isotactic index). (I
I) and the like), and the amount of additives that can have a plasticizing effect at the time of stretching can be controlled, and the optimum film forming conditions and raw materials can be appropriately selected within a range that does not impair the characteristics of the present invention. Good. Y (MD) at 80 ° C. is more preferably 0.5 GPa or more, further preferably 0.6 GPa.
That is all.

The biaxially oriented polypropylene film of the present invention has an m value m = Y (MD) / (represented by Young's modulus (Y (MD)) in the longitudinal direction and Young's modulus (Y (TD)) in the width direction. It is preferable that Y (MD) + Y (TD)) is in the range of 0.4 to 0.7 at 25 ° C. Here, the m value is the ratio of the Young's modulus in the longitudinal direction to the sum of the Young's modulus in the longitudinal direction and the width direction. Therefore, a film having an m value of <0.5 has a higher rigidity in the width direction as compared with the longitudinal direction, and a film having an m value of 0.5 has a substantially balanced rigidity in the longitudinal direction and the width direction. Value> 0.
The film No. 5 has higher rigidity in the longitudinal direction than in the width direction. When the m value is 0.4 to 0.7, it is possible to obtain a very strong film having a balanced rigidity. If the m value at 25 ° C. is less than 0.4, the rigidity in the longitudinal direction is inferior to that in the width direction, and the rigidity becomes unbalanced, so that the tensile strength during film processing is insufficient, It is not preferable because the waist may become insufficient. When the m value exceeds 0.7, the rigidity in the width direction is significantly reduced as compared with the longitudinal direction, and the stiffness of the film may be insufficient, which is not preferable.

The m value at 25 ° C. is the film forming conditions (cooling drum temperature when cooling and solidifying from a molten state to obtain an unstretched sheet, longitudinal / transverse stretching temperature, magnification, relaxation of the film after longitudinal / transverse stretching, etc.). ), The crystallinity of the polypropylene used (corresponding to the mesopentad fraction (mmmm) and the isotactic index (II)), and the amount of additives that can have a plasticizing effect during stretching, and the like. The optimum film forming conditions and raw materials may be appropriately selected within a range that does not impair the characteristics of 1. The m value at 25 ° C. is more preferably 0.42 to 0.68, still more preferably 0.44.
˜0.65, most preferably 0.46 to 0.62. Further, it is preferable that the m value similarly satisfies 0.4 to 0.7 even at 80 ° C.

The biaxially stretched polypropylene film of the present invention preferably has an F2 value in the longitudinal direction at 25 ° C. of 40 MPa or more. Here, the F2 value in the longitudinal direction means a sample cut out in a size of 15 cm in the longitudinal direction and 1 cm in the width direction, with an original length of 50 mm and a pulling speed of 300 mm.
The stress applied to the sample at an elongation of 2% when stretched at 1 / min. If the F2 value in the longitudinal direction at 25 ° C is less than 40 MPa, the pitch will shift during printing, the film will stretch during lamination, and film cracking will occur if the film is coated or vapor-deposited. May run short. The F2 value in the longitudinal direction at 25 ° C is more preferably 45 MPa or more.

The biaxially oriented polypropylene film of the present invention preferably has an F5 value in the longitudinal direction at 25 ° C. of 50 MPa or more. Here, the F5 value in the longitudinal direction means a sample cut out in a size of 15 cm in the longitudinal direction and 1 cm in the width direction, when the original length is 50 mm and the elongation is 5% when stretched at a pulling speed of 300 mm / min. This is the stress.
If the F5 value in the longitudinal direction at 25 ° C is less than 50 MPa, the pitch will shift during printing, the film will stretch during lamination, and film cracking will occur when the film is coated or vapor-deposited. May run short. The F5 value in the longitudinal direction at 25 ° C is
It is more preferably 55 MPa or more.

The heat shrinkage ratio of the biaxially oriented polypropylene film of the present invention in the longitudinal direction at 120 ° C. is preferably 5% or less. Thermal shrinkage in the longitudinal direction at 120 ° C is 5
If it exceeds%, the shrinkage of the film becomes large when a temperature is applied during the processing such as printing, laminating, coating, vapor deposition, etc., which may induce process defects such as film omission, pitch shift, and wrinkles. The thermal shrinkage in the longitudinal direction at 120 ° C. is the cooling drum temperature when cooling and solidifying from the molten state to obtain an unstretched sheet, the longitudinal stretching conditions (stretching temperature, draw ratio, relaxation of the film after longitudinal stretching, etc.), polypropylene used (Corresponding to mmmm, II, etc.) and the mixing amount of additives capable of having a plasticizing effect at the time of stretching, and the like. The raw material should be selected. More preferably, the thermal shrinkage in the longitudinal direction at 120 ° C. is 4% or less.

The sum of the heat shrinkage rates in the longitudinal direction and the width direction at 120 ° C. of the biaxially oriented polypropylene film of the present invention is
It is preferably 8% or less, and more preferably 6% or less. The sum of the heat shrinkage ratios in the longitudinal and width directions at 120 ° C is 8
When it exceeds%, the shrinkage of the film becomes large when a temperature is applied during processing such as printing, laminating, coating and vapor deposition, which may induce process defects such as film omission, pitch shift and wrinkle. The sum of the heat shrinkage ratios in the longitudinal direction and the width direction at 120 ° C is the film forming conditions (cooling drum temperature when cooling and solidifying from a molten state to obtain an unstretched sheet, longitudinal / transverse stretching temperature, magnification, longitudinal / transverse stretching). It can be controlled by, for example, the relaxation of the film afterwards), the crystallinity of the polypropylene used (corresponding to mmmm, II, etc.), the mixing amount of additives that can have a plasticizing effect during stretching, and the characteristics of the present invention are impaired. The optimum film forming conditions and raw materials may be appropriately selected within the range that does not exist. More preferably, the sum of the heat shrinkage rates in the longitudinal direction and the width direction at 120 ° C. is 6% or less.

The water vapor transmission rate of the biaxially oriented polypropylene film of the present invention is preferably 1.5 g / m ² /d/0.1 mm or less. Water vapor transmission rate is 1.5g / m
If it exceeds ^{2 /} d / 0.1 mm, the biaxially stretched polypropylene film of the present invention may be inferior in moisture resistance when used as a package for shielding the contents from the outside air. The water vapor transmission rate depends on film forming conditions (cooling drum temperature when cooling and solidifying from a molten state to obtain an unstretched sheet, longitudinal and transverse stretching temperatures, magnification, etc.), crystallinity of polypropylene used (mmmm,
(Corresponding to II, etc.), it can be controlled by the mixing amount of additives that can have a plasticizing effect during stretching, and the optimum film forming conditions and raw materials can be appropriately selected within a range that does not impair the characteristics of the present invention. . More preferably 1.2 g / m ² / d
/0.1 mm or less.

Known methods can be used for producing the biaxially oriented polypropylene film of the present invention. For example, polypropylene containing polypropylene satisfying the above formula (1) log (MS)> − 0.61 log (MFR) +0.82 (1) or the above formula (2) log (MS)> − 0.61 log (MFR) +0. 0.52 (2) polypropylene mixed with at least one of a petroleum resin substantially free of polar groups and / or a terpene resin substantially free of polar groups is supplied to an extruder to obtain 200- It is melted at a temperature of 290 ° C., passed through a filtration filter, extruded from a slit-shaped die, wound around a cooling drum, and cooled and solidified into a sheet to obtain an unstretched film. The temperature of the cooling drum is set to 20 to 100 ° C., and it is preferable to appropriately crystallize the film from the viewpoint of improving rigidity in the longitudinal direction.

Then, the obtained unstretched film is biaxially stretched by a known longitudinal-transverse sequential biaxial stretching method. An important point for producing a biaxially stretched polypropylene film that is highly strengthened in the longitudinal direction is the stretching ratio in the longitudinal direction (= longitudinal direction). The effective stretching ratio in the longitudinal direction when forming a normal longitudinal-transverse biaxially oriented polypropylene film is in the range of 4.5 to 5.5 times, and if it exceeds 6 times, stable film formation becomes difficult. In contrast, the film is torn by transverse stretching, whereas in the biaxially stretched polypropylene film of the present invention, the effective stretching ratio in the machine direction is preferably 6 times or more. If the effective stretching ratio in the machine direction is less than 6 times, the rigidity of the obtained film in the machine direction may be insufficient, and the rigidity of the film when it is made thin may be insufficient. The effective stretching ratio in the machine direction is more preferably 7 times or more, further preferably 8 times or more. At this time, it may be preferable to carry out the longitudinal stretching in at least two stages from the viewpoint of strengthening in the longitudinal direction. The longitudinal stretching temperature may be appropriately selected from the viewpoints of stable film-forming property and strengthening in the longitudinal direction.
It is preferably 0 to 150 ° C. In the cooling process after longitudinal stretching, it is preferable from the viewpoint of dimensional stability in the longitudinal direction to provide relaxation in the longitudinal direction to the extent that unevenness in film thickness is not deteriorated.

The effective stretching ratio in the width direction is preferably 10 times or less. If the effective stretching ratio in the width direction exceeds 10 times, the rigidity of the obtained film in the longitudinal direction may be insufficient or the film formation may become unstable. The transverse stretching temperature may be appropriately selected from the viewpoints of stable film formation, thickness unevenness, strengthening in the longitudinal direction, and the like.
Is preferred.

After stretching in the width direction, 1 is further applied in the width direction.
Heat setting at 150-180 ° C while giving relaxation of more than 50%,
The biaxially oriented polypropylene film of the present invention can be obtained by cooling and winding.

An example of the production method when the biaxially oriented polypropylene film of the present invention is used as a film for metal vapor deposition will be described, but the present invention is not limited to the production method described below.

For example, polypropylene containing polypropylene satisfying the above formula (1) log (MS)>-0.61 log (MFR) +0.82 (1), or the above formula (2) log (MS)>-0.61 log. A resin in which polypropylene satisfying (MFR) +0.52 (2) is mixed with at least one kind of petroleum resin substantially free of polar group and / or terpene resin substantially free of polar group, and / or a third
Layers of resin are prepared, these are supplied to separate extruders, melted at a temperature of 200 to 290 ° C., passed through a filtration filter, and then merged in a short tube or a die to obtain a desired laminated thickness. Is extruded from the slit-shaped die, wound around a cooling drum, and cooled and solidified into a sheet to obtain an unstretched laminated film. The temperature of the cooling drum is 20-9
It is preferable that the temperature is 0 ° C. and the film is appropriately crystallized from the viewpoint of improving rigidity in the longitudinal direction.

This unstretched laminated film is used in the range of 120-150.
After heating to a temperature of ℃, stretched 6 times or more in the longitudinal direction, then introduced into a tenter type stretching machine and stretched 10 times or less in the width direction at 150 to 180 ° C., followed by relaxation heat treatment at 150 to 180 ° C., Cooling. Further, if necessary, the surface of the base layer on which the metal vapor deposition layer is provided and / or the third surface on the opposite side is subjected to corona discharge treatment in air, nitrogen, or a mixed atmosphere of carbon dioxide and nitrogen. At this time, when a heat seal layer is laminated as the third layer, it is preferable not to perform corona discharge treatment in order to obtain high adhesive strength. Then
The film is wound into a biaxially oriented polypropylene film for metal vapor deposition.

When the film having a further improved gas barrier property is used, the unstretched laminated film may have a thickness of 120 to
After heating to a temperature of 150 ° C, stretching in the longitudinal direction 6 times or more, then cooling and coating the above coating layer coating agent on the uniaxially stretched film base layer (corona discharge treatment is applied to the base layer surface if necessary) And then introduced into a tenter type stretching machine 15
After stretching 10 times or less in the width direction at 0 to 180 ° C.,
Relaxation heat treatment is performed at 0 to 180 ° C. and cooling is performed. Further, if necessary, the surface provided with the coating layer of the base layer and / or the surface of the third layer on the opposite side is subjected to corona discharge treatment in air, nitrogen, or a mixed atmosphere of carbon dioxide and nitrogen. At this time, the third
When a heat-sealing layer is laminated as a layer, it is preferable not to perform corona discharge treatment in order to obtain high adhesive strength. Then, the film is wound into a biaxially oriented polypropylene film for metal vapor deposition.

Aging of the biaxially oriented polypropylene film for metal vapor deposition obtained in the present invention at 40 to 60 ° C. promotes the reaction of the coating layer, thereby improving the adhesive strength with the base layer, and It is preferable because the adhesive strength with the vapor deposition layer is also improved and the gas barrier performance is improved.
The aging time is preferably 12 hours or longer from the viewpoint of improving the chemical resistance, and more preferably 24 hours or longer.

Next, metal vapor deposition is carried out by vacuum vapor deposition of metal, and the metal is vapor deposited from an evaporation source to form a vapor deposition layer on the coating layer surface of the biaxially oriented polypropylene film for metal vapor deposition obtained in the present invention.

As the evaporation source, a resistance heating type boat, a crucible type using radiation or high frequency heating,
There is a method using electron beam heating, but the method is not particularly limited.

The metals used for this vapor deposition are Al and Z.
Metals such as n, Mg, Sn and Si are preferable, but Ti,
In, Cr, Ni, Cu, Pb, Fe, etc. can also be used. These metals are preferably processed into a granular, rod-shaped, tablet-shaped, wire-shaped or crucible-shaped material having a purity of 99% or more, preferably 99.5% or more.

Among the vapor-deposited metals, it is preferable to provide the vapor-deposited layer of aluminum on at least one side in terms of durability, productivity and cost of the metal vapor-deposited layer. At this time, other metal components such as nickel, copper, gold, silver, chromium, and zinc can be vapor-deposited simultaneously or sequentially with aluminum.

The thickness of the metal vapor deposition layer is preferably 10 nm or more in order to exhibit high gas barrier performance.
More preferably, it is 20 nm or more. The upper limit of the vapor deposition layer is not particularly set, but from the viewpoint of economy and productivity, it is more preferably less than 50 nm.

The glossiness of the metal vapor deposition layer is preferably 600% or more, more preferably 700% or more.

Further, a metal oxide vapor-deposited layer is additionally provided, which is suitably used as a transparent packaging film or the like as a transparent gas barrier film having an excellent gas barrier property. Here, the vapor deposition film of metal oxide is a film of metal oxide such as incomplete aluminum oxide or incomplete silicon oxide, and in particular, incomplete aluminum oxide is used in terms of durability, productivity, and cost of the vapor deposition layer. preferable. These vapor deposition methods can be performed by known methods. For example, in the case of an incomplete aluminum oxide film, the film is run in an advanced vacuum device with a vacuum degree of 10 −4 Torr or less to heat and melt the aluminum metal. Evaporate, supply a small amount of oxygen gas to the evaporation location, agglomerate and deposit on the film surface while oxidizing aluminum,
Attach a vapor deposition layer. The thickness of the deposited layer of metal oxide is 10 to
The range of 50 nm is preferable, and more preferably 10-3.
It is in the range of 0 nm. The degree of incompleteness of the vapor-deposited layer of metal oxide is such that the light transmittance of the metal oxide vapor-deposited film changes as the oxidation progresses after vapor deposition, and the light transmittance is preferably 70-9.
It is in the range of 0%. A light transmittance of less than 70% is not preferable because the contents are difficult to see through in a packaging bag. Further, when the light transmittance exceeds 90%, the gas barrier performance tends to be insufficient when used as a packaging bag, which is not preferable.

The adhesive strength between the coating layer of the metal vapor-deposited biaxially oriented polypropylene film obtained in the present invention and the metal vapor-deposited layer and the metal oxide vapor-deposited film is preferably 0.6 N / cm or more, and 0.8 N / cm or more. Is more preferable. If the adhesive strength is less than the above range, the vapor-deposited film may be stripped off when the vapor-deposited film is rolled up in a roll shape and unwound during secondary processing, and the gas barrier performance may deteriorate.

The gas barrier performance of the biaxially stretched polypropylene film of the present invention provided with a metal vapor deposition film and a metal oxide vapor deposition has a water vapor permeability of 4 g / m 2.
² / d or less, preferably 1 g / m ² / d or less, and oxygen permeability of 200 ml / m ² / d / MPa or less, preferably 100 ml / m ² / d / MPa for use as a food packaging bag It is preferable when there is.

The biaxially stretched polypropylene film of the present invention has increased rigidity in the longitudinal direction without deteriorating important characteristics such as dimensional stability and moisture resistance as compared with the conventional biaxially stretched polypropylene film, This not only makes the film easier to handle, but also exhibits excellent tensile strength against processing tension during film processing such as printing, laminating, coating, vapor deposition, and bag making. Trouble can be solved. Further, compared with the conventional polypropylene, the rigidity is high in the longitudinal direction even if the thickness is the same, and the tensile strength is excellent. Therefore, the processing characteristics can be maintained even when the film is thinner than the conventional biaxially oriented polypropylene film. From the above, the biaxially oriented polypropylene film of the present invention can be preferably used for packaging, industrial use and the like.

[Measurement Method of Characteristic Value] Terms and measurement methods used in the present invention will be collectively described below. (A) Melt tension (MS) Melt tension (MS) was measured according to JIS K7210. Using a melt tension tester manufactured by Toyo Seiki, polypropylene was heated to 230 ° C, molten polypropylene was discharged at an extrusion speed of 15 mm / min to form a strand, and the tension at the time of drawing this strand at a rate of 6.5 m / min was measured. Then, it is referred to as MS. (A) (MFR) Measured according to the polypropylene test method (230 ° C., 2.16 kgf) shown in JIS K6758. (C) Mesopentad Fraction (mmmm) Polypropylene was dissolved in o-dichlorobenzene-D6, and ¹³ C-NMR was measured at a resonance frequency of 67.93 MHz using a JEOL JNM-GX270 apparatus. For the attribution of the obtained spectra and the calculation of the mesopentad fraction, see T.W. Method performed by Hayashi et al. (P
Polymer, 29, 138-143 (1988)), for the spectrum derived from a methyl group, mmmm
Each peak was assigned with the peak at 21.855 ppm, the peak area was determined, and the ratio to the total peak area derived from the methyl group was displayed as a percentage. The detailed measurement conditions are as follows.

Measurement concentration: 15 to 20 wt% Measurement solvent: o-dichlorobenzene (90 wt%) / benzene-D6 (10 wt%) Measurement temperature: 120 to 130 ° C. Resonance frequency: 67.93 MHz Pulse width: 10 μsec (45 ° Pulse) Pulse repetition time: 7.091 seconds Data point: 32K Number of integrations: 8168 Measurement mode: Noise decoupling (d) Isotactic index (II) Polypropylene 2 with n-heptane at a temperature of 60 ° C or lower
Extract for a period of time to remove additives in polypropylene resin. Then, it is vacuum dried at 130 ° C. for 2 hours. A sample of weight W (mg) is taken from this, placed in a Soxhlet extractor and extracted with boiling n-heptane for 12 hours. Next, this sample was taken out and thoroughly washed with acetone, and then at 130 ° C. for 6 hours.
Vacuum drying for an hour, then cooling to room temperature, weight W '(m
g) was measured and determined by the following formula.

II = (W ′ / W) × 100 (%) (e) Intrinsic viscosity ([η]) For polypropylene dissolved in tetralin at 135 ° C., an Ostwald viscometer manufactured by Mitsui Toatsu Chemicals, Inc. was used. It was measured using. (F) Glass transition temperature (Tg) Thermal analyzer R manufactured by Seiko Instruments
A DC220 type was filled with a sample weight of 5 mg in an aluminum pan and loaded, and the temperature was raised at a rate of 20 ° C./min.
From the obtained calorimetric curve, the company's thermal analysis system SSC52
The glass transition temperature (Tg) was defined as the starting point of the glass transition using a built-in program of 00. (G) Bromine number Measured according to JIS K-2543-1979. It is represented by g of bromine added to unsaturated components in 100 g of the sample oil. (H) Young's modulus in the longitudinal direction, F2 value, F5 value Young's modulus at 25 ° C, F2 value, F5 value are film strength / elongation measuring device (AMF / RTA) manufactured by Orientec Co., Ltd.
-100) at 65% RH. Measuring direction of sample: 15 cm, direction perpendicular to measuring direction: 1c
Cut to m size, original length 50mm, pulling speed 30
Stretched at 0 mm / min, Young's modulus is JIS-Z1702
The measurement was carried out according to the method specified in 1. Also, F2 value, F5
The values were obtained by measuring the stress applied to the sample for elongation of 2% and 5%, respectively. Also, when performing measurements at high temperatures such as 80 ° C, equip a high and low temperature constant temperature bath manufactured by Gondo Scientific Co., Ltd.
The measurement was performed under the same conditions as above. (K) A sample having a trial length of 260 mm and a width of 10 mm is sampled from the film with the heat shrinkage measurement direction being the longitudinal direction and the width direction, and a mark is placed at a position of 200 mm as the original size (L ₀ ). A load of 3 g is applied to the lower end of this sample, the sample is heat-treated in a hot air circulation oven at 120 ° C. for 15 minutes and then taken out at room temperature, and the length (L ₁ ) marked on the sample is measured. At this time, the heat shrinkage rate is calculated by the following equation. The above operation was performed in each direction (the length direction and the width direction) to obtain the sum of the heat shrinkage rates in the length direction and the width direction.

Thermal shrinkage (%) = 100 × (L ₀ −L ₁ ) / L ₀ (CO) Center line average surface roughness (Ra) Measured using a stylus surface roughness meter according to JIS B0601. . In addition, using a high precision thin film step measuring device (model: ET-30HK) manufactured by Kosaka Laboratory Ltd., stylus diameter cone type 0.5 μmR, load 16 mg, cutoff 0.0.
It was 8 mm.

At this time, the center line average surface roughness (Ra) is
A portion having a measurement length L was extracted from the roughness curve in the direction of the center line, the center line of the extracted portion was taken as the X axis, and the vertical direction was taken as the Y axis, and the roughness curve was represented by y = f (x). At this time, the value obtained by the following formula is expressed in μm. (S) Thickness of coating layer, thickness of vapor-deposited metal layer and deposition layer of metal oxide Using a transmission electron microscope (TEM), the cross-sectional structure of the film was observed to measure the laminated thickness and the thickness structure. (S) Film surface glossiness Based on JIS Z8741 method, it was determined as a 60 ° specular glossiness by using a digital gonio gloss meter UGV-5D manufactured by Suga Test Instruments. (B) Surface gloss of metal vapor deposition film A metal vapor deposition biaxially oriented polypropylene film was loaded in a continuous vacuum vapor deposition apparatus, aluminum was evaporated from an electron beam heating evaporation source, and the film was continuously run while Macbeth Co. Aluminum was vapor-deposited in the range where the optical density (−log (light transmittance)) measured using an optical densitometer (TR927) was 1.9 to 2.1. The metal vapor deposition surface of this metal vapor deposition film was measured according to JIS Z8741 to determine the surface gloss. (C) Adhesive strength The adhesive strength between the surface layer and the coating layer of the metal-deposited biaxially oriented polypropylene film is measured by using a polyurethane adhesive as a 20 μm thick biaxially oriented polypropylene film (S645 manufactured by Toray) on the surface of the coating layer. Laminating and 48 at 40 ℃
After being left for a time, it was measured by 90 ° peeling with a peeling speed of 10 cm / min using a Tensilon manufactured by Toyo Baldwin with a width of 15 mm. The adhesive strength between the metal vapor deposition layer and the metal oxide vapor deposition layer and the polypropylene film for metal vapor deposition is the same as the above on the surface of the metal vapor deposition layer and the metal oxide vapor deposition layer.
Biaxially oriented polypropylene film of 0 μm thickness (Toray S
645) was attached using a polyurethane adhesive and measured in the same manner as above. (SO) Oxygen Permeability Metal Vapor Deposition A polypropylene adhesive film (3M, Scotchmark, 40 μm thick) is attached to the metal vapor-deposited surface of a biaxially stretched polypropylene film, and oxygen transmission by MOCON / Modern Controls is performed. Using the rate measuring device Oxtran2 / 20,
The measurement was performed under the conditions of a temperature of 23 ° C. and a humidity of 0% RH. (T) Water vapor transmission rate For biaxially stretched polypropylene film alone, MO
Using a water vapor transmission rate measurement device PERMATRAN-W3 / 30 manufactured by CON / Modern Controls, the measurement was performed under the conditions of a temperature of 40 ° C. and a humidity of 90% RH. Regarding the metal vapor-deposited biaxially oriented polypropylene film, a polypropylene adhesive film (3M, Scotchmark, 40 μm thickness) was attached to the metal vapor-deposited surface, and the measurement was performed under the above conditions. (H) Effective stretching ratio An unstretched film extruded from a slit-shaped die, wound around a metal drum, and cooled and solidified on a sheet has a length of 1
Each side of the square of the cm is the longitudinal direction of the film,
After marking so as to be parallel to the width direction, stretching and winding were performed, and the length (cm) of the squares of the obtained film was measured, and this was taken as the effective stretching ratio in the longitudinal and lateral directions. (T) Secondary processability A biaxially stretched polypropylene film of the present invention having a length of 1000 m and a thickness of 15 μm, or a metal vapor-deposited biaxially stretched polypropylene film, and an unstretched polypropylene film having a thickness of 20 μm (metal vapor-deposited biaxially stretched polypropylene film). In the case of a film, the film was laminated on the surface opposite to the surface on which metal vapor deposition was performed to form a food packaging film. With the unstretched polypropylene film layer facing the inside of the film,
Vertical pillow packaging machine made by Fujikikai Co., Ltd. (FUJIF
W-77) was used to insert the film into a tubular shape to make a bag.

At that time, the film having no wrinkle or elongation and having a good shape of the bag-making product was evaluated as ◯, the Young's modulus in the longitudinal direction of the film was low, or the film was stretched due to its low waist.
The case where the shape of the bag-made product was bad due to bad slippage or wrinkles due to a large heat shrinkage was evaluated as x.

[0117]

EXAMPLES The present invention will be described based on examples. In addition,
In order to obtain a film having a desired thickness, the rotation speed of the extruder and the peripheral speed of the cooling drum were adjusted to predetermined values unless otherwise specified.

Example 1 Melt tension (MS) was 1.5 cN, melt flow rate (MFR) was 2.3 g / 10 min, mesopentad fraction (mmmm) was 92%, and isotactic index (II) was 96%. To known polypropylene which is
Is 20 cN, MFR is 3 g / 10 minutes, mmmm is 97
%, II is 96.5%, and polypropylene obtained by adding and mixing a high melt tension polypropylene (HMS-PP) having a long chain branch satisfying the relationship between MS and MFR of the formula (1) at a ratio of 10% by weight. 90% by weight is a petroleum resin which is compatible with polypropylene and has a plasticizing effect at the time of stretching as a petroleum resin which does not substantially contain a polar group.
Resin 100 in which 10% by weight of polydicyclopentadiene having a bromine number of 3 cg / g and a hydrogenation rate of 99% is added and mixed.
To parts by weight, crosslinked particles of a polymethacrylic acid-based polymer (crosslinked PMMA) having an average particle diameter of 2 μm as crosslinked organic particles were added in an amount of 0.
Add 15 parts by weight, mix glycerin fatty acid ester and alkyldiethanolamine fatty acid ester as an antistatic agent in a ratio of 1: 1 and add 0.8 parts by weight, and feed to a twin-screw extruder to form a gut at 240 ° C. Extruded, cooled through a water bath at 20 ° C, cut into 3 mm lengths with a tip cutter, and then fed with chips dried at 100 ° C for 2 hours into a uniaxial extruder to melt at 260 ° C, and after passing through a filtration filter, slit. It was extruded from the die and wound on a metal drum at 25 ° C to form a sheet.

This sheet is preheated by passing through a roll kept at 135 ° C., passed between rolls kept at 140 ° C. and having a peripheral speed difference, stretched 8 times in the longitudinal direction and immediately cooled to room temperature. Continue to introduce this stretched film into the tenter and
Preheat at 65 ° C, stretch 7 times in the width direction at 160 ° C, then heat-fix at 160 ° C while giving 6% relaxation in the width direction, then cool and wind, biaxially 15 μm thick A stretched polypropylene film was obtained.

The raw material composition of the obtained film and the evaluation results of the film characteristics are summarized in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 2 A biaxially stretched polypropylene film having a thickness of 15 μm was produced under the same conditions as in Example 1 except that the stretching ratio was increased to 10 times.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 3 In Example 1, the mixing ratio of HMS-PP having a long chain branch was 5% by weight, and the amount of polydicyclopentadiene added was 3% by weight. The longitudinal direction was 8 times, and the width direction was 8 times. Example 3 was a biaxially stretched polypropylene film having a thickness of 15 μm, which was produced under the same conditions except that it was stretched.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 4 A biaxially stretched polypropylene film having a thickness of 15 μm produced under the same conditions as in Example 3 except that the mixing ratio of HMS-PP having long chain branches was 3% by weight. did.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 5 In Example 1, a terpene resin that does not substantially contain a polar group as an additive that is compatible with polypropylene and has a plasticizing effect during stretching, Tg 75 ° C., bromine number 4 cg. / G, 5% by weight of β-pinene having a hydrogenation rate of 99% was mixed and stretched 9 times in the longitudinal direction and 7 times in the width direction to prepare a biaxially stretched polypropylene film having a thickness of 15 μm produced under the same conditions. It was set as Example 5.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 6 Melt tension (MS) was 20 cN, melt flow rate (M
FR) is 3 g / 10 minutes, mesopentad fraction (mmm
m) 97%, isotactic index (II)
Is 96.5%, and the melt tension (M
S) and 85% by weight of HMS-PP having long chain branching satisfying the relationship of melt flow rate (MFR) are compatible with polypropylene and have a polar group as an additive which can have a plasticizing effect during stretching. Resin composition 1 containing 15% by weight of hydrogenated β-dipentene having a Tg of 75 ° C., a bromine number of 3 cg / g and a hydrogenation rate of 99%, which is a terpene resin not included in
0.10 parts by weight of polystyrene-based polymer cross-linked particles (cross-linked PS) having an average particle diameter of 1 μm as cross-linked organic particles were added to 00 parts by weight.
0.8 parts by weight of glycerin fatty acid ester and alkyldiethanolamine fatty acid ester as an antistatic agent are mixed at a ratio of 1: 1 and added to a twin-screw extruder and extruded into a gut shape at 240 ° C. After passing through a 20 ° C water bath to cool and cutting to a 3 mm length with a chip cutter, the chips dried at 100 ° C for 2 hours are fed to a uniaxial extruder to melt at 260 ° C, and after passing through a filtration filter, slit shape It was extruded from the die and wound on a metal drum at 30 ° C. to form a sheet.

The sheet was preheated through a roll kept at 133 ° C., passed between rolls kept at 138 ° C. and provided with a peripheral speed difference, stretched 8 times in the longitudinal direction and immediately cooled to room temperature. Continue to introduce this stretched film into the tenter and
Preheat at 63 ° C, stretch 8 times in the width direction at 160 ° C, then heat set at 160 ° C while giving a relaxation of 8% in the width direction, cool and wind to obtain a film with a thickness of 15 μm. An axially stretched polypropylene film was obtained.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 7 Melt tension (MS) was 1.5 cN, melt flow rate (MFR) was 2.3 g / 10 minutes, mesopentad fraction (mmmm) was 92%, and isotactic index (II) was 96%. The known polypropylene has a melt tension (MS) of 20 cN and a melt flow rate (MF).
R) is 3 g / 10 minutes, mesopentad fraction (mmmm)
97%, isotactic index (II) 9
HMS-PP having a long chain branching ratio of 6.5%, which satisfies the relational expression of melt tension (MS) and melt flow rate (MFR) of the above formula (1), was added and mixed at a ratio of 5% by weight. A terpene resin that is compatible with polypropylene in 80% by weight of polypropylene and has substantially no polar group as an additive capable of having a plasticizing effect during stretching.
g75 ° C, a bromine number of 4 cg / g, a hydrogenation rate of 99% β-pinene and Tg75 ° C, a mixture of a bromine number of 3 cg / g and a hydrogenation rate of 99%, hydrogenated β-dipentene resin was mixed by 20% by weight,
A 15 μm thick biaxially oriented polypropylene film was produced under the same conditions as in Example 6 except that the film was stretched 11 times in the longitudinal direction and 6 times in the width direction.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 8 In Example 3, as HMS-PP, melt tension (M
S) is 15 cN and melt flow rate (MFR) is 2.
0g / 10 minutes, mesopentad fraction (mmmm) is 9
6.5%, isotactic index (II) is 9
A thickness produced under the same conditions except that HMS-PP having a long chain branching of 7% and satisfying the relationship between the melt tension (MS) and the melt flow rate (MFR) of the formula (1) was used. A 15 μm biaxially oriented polypropylene film was used as Example 8.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, excellent tensile strength, dimensional stability, moisture resistance, and secondary processability.

Example 9 In Example 3, as HMS-PP, melt tension (M
S) is 30 cN and melt flow rate (MFR) is 2.
1g / 10 minutes, mesopentad fraction (mmmm) is 97
%, The isotactic index (II) was 97%, and HMS-PP having long chain branching was used, which satisfies the relationship between the melt tension (MS) and the melt flow rate (MFR) of the formula (1). Example 9 is a biaxially stretched polypropylene film having a thickness of 15 μm, which is manufactured under the same conditions except for Example 9.
And

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 10 In Example 5, the mixing ratio of HMS-PP having long-chain branch was set to 20% by weight, and the mixture was compatible with polypropylene.
The same except that polydicyclopentadiene having a Tg of 80 ° C., a bromine number of 3 cg / g, and a hydrogenation rate of 99%, which is a petroleum resin that does not substantially contain a polar group, is used as an additive capable of having a plasticizing effect during stretching. 15μm thickness produced under the conditions
The biaxially oriented polypropylene film of No. 10 was used as Example 10.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 11 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as in Example 10 except that the mixing ratio of HMS-PP was 30% by weight.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 12 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as in Example 10 except that the mixing ratio of HMS-PP was changed to 50% by weight.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 13 In Example 1, as HMS-PP, melt tension (M
S) is 1 cN, melt flow rate (MFR) is 10 g
/ 10 minutes, mesopentad fraction (mmmm) 98%,
Example 13 was a biaxially stretched polypropylene film having a thickness of 15 μm produced under the same conditions except that HMS-PP having a long chain branch having an isotactic index (II) of 98.5% was used.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 14 In Example 1, the melt tension (MS) was 1.1 cN, the melt flow rate (MFR) was 3 g / 10 min, the mesopentad fraction (mmmm) was 97.5%, and the isotactic index ( II) A polypropylene having a thickness of 15 μm produced under the same conditions except that a polypropylene obtained by adding 10% by weight of HMS-PP to a known polypropylene having 99% was stretched 9 times in the longitudinal direction and 9 times in the width direction. An axially stretched polypropylene film was used as Example 14.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 15 In Example 3, the melt tension (MS) was 1.2 cN, the melt flow rate (MFR) was 2.7 g / min, the mesopentad fraction (mmmm) was 96%, and the isotactic index (II). Example 15 was a biaxially stretched polypropylene film having a thickness of 15 μm formed under the same conditions except that polypropylene having 5% by weight of HMS-PP was added to a known polypropylene having 98%).

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 16 Thickness 1 prepared under the same conditions as in Example 3 except that the temperature of the cooling drum was raised to 80 ° C. to obtain an unstretched sheet.
Example 5 was a 5 μm biaxially oriented polypropylene film.
And

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Example 17 In Example 3, the stretching in the longitudinal direction was divided into two stages, and
After preheating at 35 ℃, 1.5 times at 137 ℃ in the first stage,
Comparative Example 17 was a biaxially stretched polypropylene film having a thickness of 15 μm, which was produced under the same conditions except that the film was stretched 5.3 times at 142 ° C. in the second stage.

The results are shown in Tables 1 and 2. The obtained film had a high Young's modulus in the longitudinal direction, was excellent in tensile strength, and was also excellent in dimensional stability, moisture resistance and secondary workability.

Comparative Example 1 Melt tension (MS) was 1.5 cN, melt flow rate (MFR) was 2.3 g / 10 minutes, mesopentad fraction (mmmm) was 92%, and isotactic index (II) was 96%. In addition, 100 parts by weight of a known polypropylene alone, which does not satisfy the relational expression of the melt tension (MS) and the melt flow rate (MFR) of the above formula (2),
0.15 parts by weight of crosslinked particles of polymethacrylic acid type polymer (crosslinked PMMA) having an average particle diameter of 2 μm was added as crosslinked organic particles, and glycerin fatty acid ester and alkyldiethanolamine fatty acid ester were added at a ratio of 1: 1 as an antistatic agent. The mixed and added 0.8 parts by weight was supplied to a uniaxial extruder, melted at 260 ° C., passed through a filtration filter, extruded from a slit-shaped die, and wound into a metal drum at 25 ° C. to form a sheet.

This sheet is preheated by passing it through a roll kept at 130 ° C., passed between rolls kept at 135 ° C. and having a peripheral speed difference, stretched 5 times in the longitudinal direction and immediately cooled to room temperature. Continue to introduce this stretched film into the tenter and
Preheat at 65 ℃, stretch 10 times in the width direction at 160 ℃,
Then, while allowing 7% relaxation in the width direction, heat setting was performed at 160 ° C., followed by cooling to obtain a biaxially stretched polypropylene film having a thickness of 15 μm.

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction, insufficient tensile strength, and was inferior in moisture resistance and secondary processability.

Comparative Example 2 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as in Comparative Example 1, except that the stretching ratio in the machine direction was increased to 7 times.

The results are shown in Tables 3 and 4. Satisfactory films could not be obtained due to frequent breakage during transverse stretching.

Comparative Example 3 In Comparative Example 1, the melt tension (MS) was 1.1 cN, the melt flow rate (MFR) was 3 g / 10 min, the mesopentad fraction (mmmm) was 97.5%, and the isotactic index ( II) Thickness 1 produced under the same conditions except that a known polypropylene simple substance having 99% is used.
A 5 μm biaxially oriented polypropylene film was used as Comparative Example 3.

The results are shown in Tables 3 and 4. Since the edges of the obtained film were curled up when wound on a cooling drum from the molten state, the sheet was often cut by longitudinal stretching.
Further, the film was not able to be industrially produced because the film was broken during the lateral stretching and scattered during the lateral drawing, resulting in poor film-forming properties as a whole.

Comparative Example 4 In Comparative Example 1, the melt tension (MS) was 0.6 cN, the melt flow rate (MFR) was 6 g / 10 min, the mesopentad fraction (mmmm) was 99.8%, and the isotactic index ( Comparative Example 4 was a biaxially stretched polypropylene film having a thickness of 15 μm produced under the same conditions except that a known polypropylene simple substance having II) of 99.5% was used.

The results are shown in Tables 3 and 4. Satisfactory films could not be obtained due to frequent breakage during transverse stretching.

Comparative Example 5 In Comparative Example 1, polypropylene alone was added to 97% by weight,
As an additive that is compatible with polypropylene and has a plasticizing effect during stretching, it is a petroleum resin that does not substantially contain a polar group, Tg 80 ° C., bromine number 3 cg / g, hydrogenation rate 9
Comparative Example 5 was a biaxially stretched polypropylene film having a thickness of 15 μm produced under the same conditions except that 9% of polydicyclopentadiene was mixed at 3% by weight and stretched 5 times in the longitudinal direction and 9 times in the width direction.

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction, insufficient tensile strength, and poor secondary processability.

Comparative Example 6 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as Comparative Example 5, except that the film was stretched 7 times in the longitudinal direction and 8 times in the width direction.

The results are shown in Tables 3 and 4. It was a film that could not be industrially produced because the film was not able to be collected into a film having a sufficient length because the film was broken during the transverse stretching.

Comparative Example 7 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as in Comparative Example 5, except that the stretching ratio in the longitudinal direction was further increased to 8 times.

The results are shown in Tables 3 and 4. Satisfactory films could not be obtained due to frequent breakage during transverse stretching.

Comparative Example 8 Thickness 1 prepared under the same conditions as in Comparative Example 5 except that the addition amount of polydicyclopentadiene was changed to 10% by weight.
A 5 μm biaxially oriented polypropylene film was used as Comparative Example 8.

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction at 80 ° C., had insufficient tensile strength, and was poor in dimensional stability and secondary workability.

Comparative Example 9 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as Comparative Example 8 except that the film was stretched 8 times in the longitudinal direction and 7 times in the width direction.

The results are shown in Tables 3 and 4. It was a film that could not be industrially produced because the film was not able to be collected into a film having a sufficient length because the film was broken during the transverse stretching.

Comparative Example 10 A biaxially stretched polypropylene film having a thickness of 15 μm was prepared under the same conditions as in Comparative Example 8 except that the stretching ratio in the longitudinal direction was further increased to 9 times.

The results are shown in Tables 3 and 4. Satisfactory films could not be obtained due to frequent breakage during transverse stretching.

Comparative Example 11 In Example 6, by using HMS-PP simple substance having long chain branching satisfying the relational expression of melt tension (MS) and melt flow rate (MFR) of the above formula (1), longitudinal direction was used. 5
Comparative Example 11 was a biaxially stretched polypropylene film having a thickness of 15 μm, which was produced under the same conditions except that it was stretched 12 times in the width direction and 12 times in the width direction.

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction, insufficient tensile strength, and was poor in secondary workability.

Comparative Example 12 In Example 5, a bromine number of 15 was obtained at Tg of 39 ° C., which contained a carboxyl group as a polar group having poor compatibility with polypropylene instead of the petroleum resin containing substantially no polar group.
Add unhydrogenated gum rosin at cg / g and add 5 in the longitudinal direction.
Comparative Example 12 was a biaxially stretched polypropylene film having a thickness of 15 μm, which was produced under the same conditions except that it was stretched 11 times in the width direction and 11 times in the width direction.

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction, insufficient tensile strength, and poor secondary processability.

Comparative Example 13 In Comparative Example 1, a longitudinally uniaxially stretched polypropylene film having a thickness of 15 μm, which was stretched 8 times in the longitudinal direction, cooled, and then wound, was used as Comparative Example 13.

The results are shown in Tables 3 and 4. The obtained film was easy to tear in the longitudinal direction and was extremely inferior in handling property of the film, and thus was inferior in secondary processability.

Comparative Example 14 Thickness 1 prepared under the same conditions as in Comparative Example 1 except that the temperature of the cooling drum was raised to 80 ° C. to obtain an unstretched sheet.
Comparative Example 14 using a 5 μm biaxially oriented polypropylene film
And

The results are shown in Tables 3 and 4. The obtained film had a low Young's modulus in the longitudinal direction, insufficient tensile strength, and was inferior in moisture resistance and secondary processability.

[0183]

[Table 1]

[0184]

[Table 2]

[0185]

[Table 3]

[0186]

[Table 4]

[0187]

INDUSTRIAL APPLICABILITY The biaxially stretched polypropylene film of the present invention has increased rigidity in the longitudinal direction without deteriorating important characteristics such as dimensional stability and moisture resistance as compared with the conventional biaxially stretched polypropylene film. In addition to excellent handling of the film, it exhibits excellent tensile strength against processing tension during film processing such as printing, laminating, coating, vapor deposition, and bag making. The trouble caused by it can be eliminated. Further, compared with the conventional polypropylene film, the rigidity is high in the longitudinal direction even if the thickness is the same, and the tensile strength is excellent. Therefore, the processing characteristics can be maintained even when the film is thinner than the conventional biaxially oriented polypropylene film.

The biaxially oriented polypropylene film of the present invention can be preferably used for packaging, industrial use and the like.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 45/00 C08L 45/00 57/02 57/02 // B29K 23:00 B29K 23:00 B29L 7:00 B29L 7 : 00 F-term (reference) 4F071 AA20 AA39 AA80 AA88 AE04 AF09 AF20Y AF61 AH04 BB08 BC01 4F100 AB01B AB01C AK02A AK07A AK51D AK51E BA02 BA03 BA04 BA05 BA06 BA07 BA10A BA10B BA10C CA04A EH66B EH66C EJ38A GB15 JA06A JA11A JK02A JK06 JK07A YY00A 4F210 AA11B AA49 AB07 QC05 QC06 QG01 QG18 4J002 BA012 BB121 BB141 BB151 BK002 CE002 FD022 FD060 FD070 FD170 FD200 GF00 GG02

Claims (9)

[Claims] 1. Melt tension (M) when measured at 230 ° C.
S) and the melt flow rate (MFR) include polypropylene that satisfies the following formula (1) log (MS)>-0.61 log (MFR) +0.82 (1) and is compatible with polypropylene. A biaxially stretched polypropylene film comprising one or more additives capable of having a plasticizing effect during stretching. 2. The biaxially oriented polypropylene film according to claim 1, wherein the additive is a petroleum resin substantially free of a polar group and / or a terpene resin substantially free of a polar group. 3. Melt tension (M) when measured at 230 ° C.
S) and melt flow rate (MFR) have the following formula (2): log (MS)>-0.61 log (MFR) +0.52 (2). A biaxially oriented polypropylene film, characterized in that one or more additives capable of having a plasticizing effect are mixed. 4. The biaxially oriented polypropylene film according to claim 3, wherein the additive is a petroleum resin substantially free of a polar group and / or a terpene resin substantially free of a polar group. 5. The polypropylene has a mesopentad fraction (mmmm) in the range of 90 to 99.5%.
The biaxially oriented polypropylene film according to any one of 1 to 4. 6. A Young's modulus (Y (M
The biaxially oriented polypropylene film according to any one of claims 1 to 5, wherein D)) is 2.5 GPa or more. 7. An m value represented by Young's modulus (Y (MD)) in the longitudinal direction and Young's modulus (Y (TD)) in the width direction, m = Y (MD) / (Y (MD) + Y (TD). ) Is in the range of 0.4 to 0.7 at 25 ° C., The biaxially oriented polypropylene film according to claim 1. 8. The biaxially stretched polypropylene film according to claim 1, which is a film having a metal vapor deposition layer provided on at least one surface thereof. 9. A thickness of 0.05 to 2 on at least one side.
μm polyester urethane resin coating agent,
A film in which a metal vapor deposition layer is sequentially provided, and the adhesive strength between the base layer and the coating layer is 0.6 N / cm or more.
The biaxially oriented polypropylene film according to any one of 7 above.