JP2972399B2 - Metallized polyolefin film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal-deposited polyolefin film, and more particularly, to the adhesive strength of a deposited film,
The present invention relates to a metal-deposited polyolefin film having a high brightness and glossiness on a metal-deposited surface.

[0002]

BACKGROUND OF THE INVENTION In recent years, the excellent processability and material properties of polypropylene and the excellent decorative properties and light-blocking properties of a vapor-deposited film have been utilized in recent years. The use of metal-deposited films on which is vapor-deposited is mainly used for packaging.

However, polypropylene films or propylene-based ethylene or other α-
Films made of copolymers with olefins are non-polar and have poor adhesion to other substances, so that the adhesion of metal-deposited films on these films is extremely low. Therefore, these metal vapor-deposited films are liable to peel off during a post-processing step or during use, causing a problem, and have a drawback that the range of application is greatly limited.

Various proposals have been made in the past to improve such disadvantages. For example, there is a method of imparting a polar group by treating the film surface with corona discharge, flame treatment, or the like, but this method alone is insufficient in the interlayer adhesion between the metal and the film. Also, there is a method of depositing metal after anchor coating an adhesive on this treated surface,
This method has problems that the process is complicated and the cost is high.

Also, JP-A-63-291929, JP-A-3-7-29
No. 5140 discloses that polypropylene has a specific ethylene
-It has been shown that metal deposition is performed on a film obtained by blending an olefin copolymer. However, there is a drawback that merely blending ethylene / α-olefin with polypropylene can produce only a metal-deposited film with low gloss.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems associated with the prior art as described above.
It is an object of the present invention to provide a metal-deposited polyolefin film having sufficiently high deposition strength of a deposited film and high luminance and glossiness on a metal-deposited surface.

[0007]

SUMMARY OF THE INVENTION The metal-deposited polyolefin film according to the present invention comprises (A) 60 to 99% by weight of a polypropylene resin and (B) a polyolefin random copolymer 1 to
40% by weight [Total amount of components (A) and (B) is 100
A metal-deposited polyolefin film in which a metal is deposited on the polyolefin film, wherein the polyolefin random copolymer (B) has (I) an ethylene content of 60 to 95 mol%. Wherein MFR ₂₃₀ ^° _C. is 0.1 to 50 g / 10 min.
20 to 95 parts by weight of an ethylene random copolymer comprising ethylene and an α-olefin having 3 to 20 carbon atoms,
(II) a propylene content of 60 to 95 mol%,
5-80 parts by weight of a propylene-based random copolymer consisting of propylene having an MFR of ₂₃₀ ^° _C. of 0.1 to 50 g / 10 min and ethylene or an α-olefin having 4 to 20 carbon atoms [component (I) and ( The total amount of II) is 100 parts by weight].

[0008]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the metal-deposited polyolefin film according to the present invention will be specifically described.

Polypropylene resin (A) The polypropylene resin (A) used in the present invention is a propylene homopolymer or a copolymer of propylene with ethylene and / or another α-olefin, for example, propylene and ethylene, -2 or 3 with butene etc.
A random copolymer or a block copolymer or a mixture thereof (generally, a propylene unit content is at least 90 mol%), and a boiling n-heptane insoluble content is at least 90%, preferably at least 93%. .

[0010] Such a polypropylene resin (A)
Typically, it can be produced using a catalyst formed from a solid titanium catalyst component and an organometallic compound catalyst component, or a catalyst formed from both components and an electron donor.

As the solid titanium catalyst component, titanium trichloride or a titanium trichloride composition produced by various methods,
Alternatively, a titanium catalyst component with a carrier having a specific surface area of preferably 100 m ² / g or more containing magnesium, a halogen, an electron donor, preferably an aromatic carboxylic acid ester or an alkyl group-containing ether, and titanium as essential components is exemplified. In particular, a polypropylene resin produced using the latter catalyst component with a carrier is preferred.

As the organometallic compound catalyst component, an organoaluminum compound is preferable, and specifically, trialkylaluminum, dialkylaluminum halide,
Examples thereof include alkyl aluminum sesquihalide and alkyl aluminum dihalide. Among these compounds, suitable organometallic compound catalyst components differ depending on the type of the titanium catalyst component used.

The electron donor is an organic compound containing nitrogen, phosphorus, sulfur, oxygen, silicon, boron and the like, and preferable specific examples include organic esters and organic ethers having these elements. .

A method for producing a polypropylene resin using a catalyst component with a carrier is described in, for example, Japanese Patent Application Laid-Open No. 50-108385.
No., JP-A-50-126590, JP-A-51-20297, JP-A-51
-28189 and JP-A-52-151691.

Polyolefin random copolymer (B) The polyolefin random copolymer (B) used in the present invention comprises a specific ethylene random copolymer (I) and a specific propylene random copolymer (II). Is a random copolymer composition containing at a specific ratio.

The above-mentioned ethylene random copolymer (I)
Is an elastic copolymer having a repeating unit derived from ethylene as a main repeating unit, and specifically is a random copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.

The content of the repeating unit derived from ethylene constituting the ethylene random copolymer (I) is in the range of 60 to 95 mol%, preferably in the range of 70 to 90 mol%. Is within. By setting the content of the repeating unit derived from ethylene in the ethylene-based random copolymer (I) to 60 mol% or more, blocking and the like hardly occur, and the handling property of the resin is improved. When the content of the repeating unit is 95 mol% or less, the adhesive strength of the metal-deposited film can be improved, and the impact resistance of the metal-deposited polyolefin film can be improved.

The repeating unit derived from the α-olefin constituting the ethylene-based random copolymer (I) has an α-olefin having 3 to 20, preferably 3 to 10, and more preferably 3 to 5 carbon atoms. Derived from olefins.
When the number of carbon atoms in the α-olefin exceeds 20, the effect of improving the adhesive strength of the metal-deposited film is insufficient.

Specific examples of the α-olefin include propylene, butene-1, pentene-1, 4-methylpentene-1, 3-methylpentene-1, heptene-1, and octene-1.
And decene-1 and the like. Such α-olefins may be used alone or in combination.

The content of the repeating unit derived from the α-olefin in the ethylene random copolymer (I) is inevitable when the copolymer (I) is a two-component system. , 5 to 40 mol%, preferably 10 to 30 mol%.

Such an ethylene random copolymer (I) is a soft copolymer having rubber elasticity. Therefore, the crystallinity of the copolymer (I) is usually 40 or less.
%, Preferably 20% or less.

The ethylene-based random copolymer (I) has a melt index (MFR ₂₃₀ ^° _C. ) of 0.1 to 50 measured at 230 ° C. based on ASTM-D-1238.
g / 10 minutes. In the present invention, an ethylene random copolymer having an MFR of ₂₃₀ ^° _{C. in} the range of 0.1 to 20 g / 10 minutes is preferred. MF
When an ethylene random copolymer having a R ₂₃₀ ^° _C. outside the above range is used, it is extremely difficult to disperse the polyolefin random copolymer (B) used in the present invention in polypropylene. In addition, the effect of improving the adhesive strength of the metal deposition film is not seen.

In the present invention, the value of MFR ₂₃₀ ^° _{C. is} a value measured as described above unless otherwise specified. The ethylene-based random copolymer (I) can be used alone or in combination.

The above-mentioned ethylene random copolymer (I)
Is, for example, ethylene and α in the presence of a vanadium-based catalyst.
-It can be produced by copolymerizing with an olefin.

Specific examples of the vanadium catalyst used in this method include vanadium compounds such as vanadyl trichloride, monoethoxy vanadyl dichloride, triethoxy vanadyl, vanadium oxydiacetylacetonate, and vanadium triacetylacetonate. And an organic aluminum compound.

A specific example of a method for producing an ethylene-based random copolymer using such a catalyst is specifically described below. For example, vanadium oxytrichloride and ethylene aluminum sesquichloride are used as catalysts, and hydrogen in a hexane solvent is used. In the presence of the above, continuous polymerization is carried out while continuously supplying a mixed gas of ethylene and an α-olefin having 2 to 20 carbon atoms to the reaction vessel. The ethylene-based random copolymer (I) can be obtained by continuously extracting the reaction solution containing the copolymer thus produced from the reaction vessel and separating the solvent from the reaction solution containing the copolymer. .

For example, for the ethylene random copolymer (I) produced as described above, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are determined using GPC.
Is measured and the ratio (Mw / Mn) of the two is taken, this value is usually 7 or less, preferably 3 or less.

In the present invention, the ethylene random copolymer (I) is used in an amount of from 20 to 100 parts by weight based on the total amount of the ethylene random copolymer (I) and the propylene random copolymer (II). 95 parts by weight, preferably 30 to 95 parts by weight, more preferably 40 to 90 parts by weight.

The propylene random copolymer (I)
I) is an elastic copolymer having a repeating unit derived from propylene as a main repeating unit, and is a random copolymer of propylene and ethylene or an α-olefin having 4 to 20 carbon atoms.

The propylene random copolymer (I)
The content of the repeating unit derived from propylene in I) is in the range of 60 to 95 mol%, preferably 7 to 95 mol%.
It is in the range of 0-90 mol%. By setting the content of the repeating unit derived from propylene in the propylene-based random copolymer (II) to 60 mol% or more, blocking and the like hardly occur, and the handling property of the resin is improved. By setting the content of the repeating unit to 95 mol% or less, the adhesive strength of the metal deposition film can be effectively improved.

This propylene random copolymer (I)
The repeating unit derived from the α-olefin constituting I) is ethylene or an α-olefin having 4 to 20 carbon atoms, preferably ethylene, having 4 to 10 carbon atoms.
Α-olefins, more preferably ethylene, derived from α-olefins having 4 to 5 carbon atoms. If the α-olefin has more than 20 carbon atoms, the rubbery properties of the propylene random copolymer (II) are reduced, and the effect of improving the impact resistance of the random copolymer composition cannot be expected.

Specific examples of the α-olefin include ethylene, butene-1, pentene-1, 4-methylpentene-1, 3-methylpentene-1, heptene-1, octene-1 and decene-1. And the like. Such α-olefins may be used alone or in combination.

This propylene random copolymer (I)
When the propylene-based random copolymer (II) is a two-component system, the content of the repeating unit derived from the α-olefin in I) is necessarily 5 to 5.
It is in the range of 40 mol%, preferably in the range of 10 to 30 mol%.

Propylene random copolymer (II)
Plays a role of a compatibilizer between the ethylene copolymer (I) and the polypropylene resin (A) in the polypropylene resin (A). The crystallinity of the propylene random copolymer (II) is not particularly limited, but is preferably 40% or less.

This propylene random copolymer (I)
The melt index (MFR ₂₃₀ ^° _C. ) measured at 230 ° C. according to ASTM-D-1238 of I) is 0.1 to 0.1.
It must be within the range of 50 g / 10 minutes. In the present invention, it is preferable to use a propylene random copolymer having an MFR of ₂₃₀ ^° _{C. in} the range of 1 to 20 g / 10 minutes. When a propylene-based random copolymer having an MFR of ₂₃₀ ^° _C. outside the above range is used, the dispersion of the random copolymer composition of the present invention in a polypropylene resin becomes extremely difficult. No improvement effect of the adhesive strength is seen.

Such a polypropylene random copolymer (II) is, for example, a catalyst formed from a solid titanium catalyst component and an organometallic compound catalyst component, or a catalyst formed from both of these components and an electron donor. Can be manufactured.

The solid titanium catalyst component, organometallic compound catalyst component and electron donor used in the method for producing the polypropylene random copolymer (II) are the same as those described in the method for producing the polypropylene resin (A). The same applies to the titanium catalyst component, the organometallic compound catalyst component, and the electron donor.

The propylene random copolymer (II) constituting the random copolymer composition of the present invention can be obtained, for example, by mixing a titanium catalyst with a carrier, triisobutylaluminum and diphenylmethoxysilane obtained by a conventionally known method. It is manufactured by continuous polymerization in a hexane solvent in the presence of hydrogen while continuously supplying a mixed gas of propylene and the α-olefin having 2 to 20 carbon atoms (excluding propylene). be able to. And
The reaction solution obtained by continuously performing the polymerization in this manner is continuously withdrawn from the reactor, and the solvent is separated from the reaction solution to obtain the propylene-based random copolymer (II). .

For example, for the propylene random copolymer (II) produced as described above, GPC
Is used to measure the weight average molecular weight (Mw) and the number average molecular weight (Mn), and the ratio between them (Mw / Mn) is obtained.
This value is usually 10 or less, preferably 6 or less.

In the present invention, the above-mentioned propylene random copolymer (II) comprises the above-mentioned ethylene random copolymer (I) and propylene random copolymer (I).
I) It is used in a proportion of 5 to 80 parts by weight, preferably 5 to 70 parts by weight, more preferably 10 to 60 parts by weight based on 100 parts by weight in total.

The metal-deposited polyolefin film according to the present invention is based on a polyolefin film comprising the above polypropylene resin (A) and a polyolefin random copolymer (B). The polypropylene-based resin (A) constituting the above-mentioned polyolefin film is 60 to 60% by weight based on the total amount of 100% by weight of the polypropylene-based resin (A) and the polyolefin random copolymer (B).
It is used in a proportion of 99% by weight, preferably 70 to 95% by weight. The polyolefin random copolymer (B) constituting the polyolefin film is 1 to 40% by weight, preferably 1 to 40% by weight, based on 100% by weight of the total amount of the polypropylene resin (A) and the polyolefin random copolymer (B). It is used in a ratio of 5 to 30% by weight.

If the amount of the polyolefin random copolymer (B) constituting the above-mentioned polyolefin film is less than 1% by weight, the effect of improving the adhesive strength of the metal vapor-deposited film is not preferable. On the other hand, when the amount of the polyolefin random copolymer (B) exceeds 40% by weight, the film formability is extremely reduced, the thickness unevenness and surface unevenness are remarkable, the winding appearance is inferior, and a uniform metal deposited film is obtained. It is not preferable because it is difficult to obtain.

In the composition comprising the polypropylene resin (A) and the polyolefin random copolymer (B) used in the present invention, if necessary, additives such as an antioxidant, a lubricant and an antiblocking agent may be added. It can be added in a range that does not impair the object of the invention. However, in the present invention, in order not to lower the adhesiveness of the metal-deposited film, the suitability for printing and laminating the metal-deposited surface, etc., such as to easily migrate to the surface and reduce the wettability of the polyolefin film or the metal-deposited surface. Desirably no substances are added.

In the present invention, in order to prepare a polypropylene resin composition comprising a polypropylene resin (A) and a polyolefin random copolymer (B), any conventionally known method can be employed. A method of mixing with a mixer such as a blender, a ribbon blender, a Henschel mixer, and / or a method of kneading with a kneading machine such as an extruder, a mixing roll, a Banbury mixer, a kneader, or a combination thereof, or each component is used alone. Should be mixed.

From the viewpoint of the effect of improving the adhesive strength of the metal-deposited film and the economic efficiency, the pellet-shaped or granular ethylene random copolymer (I) and the pellet-shaped or granular propylene random copolymer (II) are used. Is mixed with a mixer such as a tumbler, a ribbon blender, a Henschel mixer, and the like to form a pellet-shaped composition using an extruder, and then mixed with a polypropylene resin (A) using a tumbler or the like, and then directly formed into a film. . Needless to say, a method in which the polyolefin random copolymer (B) melt-kneaded into pellets and the polypropylene resin (A) are mixed and then melt-kneaded to form a pellet-shaped composition using an extruder or the like, and then a film is formed. Useful.

The polyolefin film used in the present invention is not only an unstretched film obtained by the usual T-die method or inflation method using the above-mentioned polypropylene resin composition as a raw material, but also the unstretched film having one or both surface layers. And a laminated film of two or more layers. In the latter case, the surface of the film obtained from the polypropylene-based resin composition is to be subjected to metal deposition. In the present invention, among these polyolefin films, after the above-mentioned polypropylene-based resin composition is melt-extruded by a T-die method, it is rapidly cooled by a cooling roll to form a film, and then at least one of the obtained films. A monolayer polyolefin film obtained by subjecting the surface to surface treatment using a conventionally known method such as corona discharge treatment, plasma treatment or an application method such as treatment in an inert gas such as nitrogen, and a single-layer polyolefin film. A stretched polyolefin film obtained by uniaxially or biaxially stretching a laminated film having a polyolefin film as one or both surface layers is excellent in various properties,
Particularly preferred.

As a method for vapor-depositing a metal on a polyolefin film surface, a raw film (an undeposited film) is usually used.
Vacuum evaporation method in which a material such as aluminum is heated and evaporated in a high vacuum device of 10 ^-3 to 10 ^-5 mmHg, and metal vapor scattered radially adheres to the surface of the surface-treated film. Is generally used, but it is also possible by conventionally known sputtering deposition or ion plating.

Alternatively, a thin film of an epoxy or urethane-based anchor coating agent may be applied to the surface-treated surface of the film, and then vapor-deposited by these methods. Specific examples of the metal deposited on the polyolefin film include aluminum, gold, silver, copper, nickel, chromium, germanium, selenium, titanium, tin, and zinc. Aluminum is preferred from the viewpoint of properties and the like.

The thickness of the metal deposition layer is usually 50 to 8
The thickness is about 00 angstroms, and double-sided, single-sided or partial vapor deposition is also possible. Further, the vapor-deposited surface can be top-coated for coloring or protection.

[0050]

According to the metal-deposited polyolefin film of the present invention, the polyolefin random copolymer (B) is dispersed in the polypropylene resin (A), so that the metal-deposited film has excellent adhesive strength. This has the effect that the low-temperature impact strength of the film is also significantly improved.

The metal-deposited polyolefin film according to the present invention has high luminance and glossiness on the metal-deposited surface.
Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

The methods for measuring physical properties and the criteria for evaluation in the examples and comparative examples are as follows. (1) Adhesive strength of metal-deposited film: After metal (aluminum) is vapor-deposited on the film, the obtained metal-deposited film is allowed to stand at 95% humidity and a temperature of 40 ° C. for 24 hours. Tape (23mm width x 65mm
Length), and when the adhesive tape was peeled off by hand, the vapor deposition power was ranked according to the area of aluminum remaining on the film surface without being peeled off by the adhesive tape, as shown in Table 1 below. Then, the adhesive strength of the metal deposition film was evaluated with this ranking.

[0053]

[Table 1] (2) Haze: The haze of an undeposited film was measured by ASTM-D-1003. The smaller the value, the better the transparency. (3) Metallic gloss: It is represented by a gloss measured at a sensitivity of 1/10 according to the specular gloss method of ASTM-D-523. The indication angle is measured at 20 degrees, and 70 or more is regarded as good.

[0054]

Example 1 Ethylene content 81 mol%, MFR₂₃₀ ^o _C 
Ethylene / propylene random weight of 5.4g / 10min
5 parts by weight of coalescing, 78 mol% of propylene content, MFR
₂₃₀ ^o _C 6.0 g / 10 min, Tm110 ° C propylene
10 parts by weight of butene-1 random copolymer
The mixture is mixed with a mixer, and the mixture is extruded into a 65 mm caliber extruder.
After melt-kneading, the mixture is extruded into strands and
The composition was obtained by cutting with a cutter.

Then, 15 parts by weight of this composition, 2.3 mol% of ethylene content, MFR ₂₃₀ ^° _C. 6.5 g / 10 min,
85 parts by weight of a polypropylene resin having a melting point (Tm) of 141 ° C. were mixed with a Henschel mixer, and the obtained composition was
It was melt-extruded at 220 ° C. using an extruder having a diameter of 65 mm and a T-die, rapidly cooled with an air knife and a cooling roll having a surface temperature of 30 ° C. to form a film. Corona discharge treatment on one side
The treatment is performed while adjusting the treatment degree to be constant, and the wetting index of the treated surface is 42 dyn / cm, the thickness is 30 μm, and the width is 5
A 0 cm roll film was obtained. The film was rewound using a slitter, cut into a width of 40 cm, and then set as a raw film in a continuous winding type vapor deposition apparatus. While continuously feeding the film, 10 ^-4 To
Aluminum was vapor-deposited on the treated surface of the film under a vacuum of rr and wound up to obtain a single-sided aluminum vapor-deposited film having a thickness of about 400 angstroms.

Table 2 shows the properties of the obtained metallized film.

[0057]

Examples 2 to 12 and Comparative Examples 1 to 5 Polyolefin films were formed in the same manner as in Example 1 in accordance with the compositions shown in Table 2, and aluminum was vapor-deposited on one side of the film in the same manner as in Example 1. I got

Table 2 shows the properties of the obtained metal-deposited film.

[0059]

[Table 2]

Claims (1)

(57) [Claims] 1. A (A) polypropylene resin of 60 to 99% by weight, and (B) a polyolefin random copolymer 1 to 1.
40% by weight [Total amount of components (A) and (B) is 100
A metal-deposited polyolefin film having a metal deposited thereon, wherein the polyolefin random copolymer (B) comprises: (I) an ethylene content of 60 to 95 mol%. And MF
20 to 95 parts by weight of an ethylene random copolymer composed of ethylene and an α-olefin having 3 to 20 carbon atoms, wherein R ₂₃₀ ^° _C. is 0.1 to 50 g / 10 min, and (II) propylene content. Is 60 to 95 mol%,
5-80 parts by weight of a propylene-based random copolymer consisting of propylene having an MFR of ₂₃₀ ^° _C. of 0.1 to 50 g / 10 min and ethylene or an α-olefin having 4 to 20 carbon atoms [component (I) and ( The total amount of II) is 100 parts by weight].