JPH0331344A - Propylene resin composition for metal deposition film - Google Patents

Abstract

PURPOSE:To obtain the title composition which can be used in packaging and ornamentation, because of extremely reduced fish eyes, excellent uniformity and good winding form by using a crystalline propylene-alpha-olefin copolymer containing a microfine powder of amorphous silica having specific average particle size and specific surface area. CONSTITUTION:(A) A crystalline propylene-alpha-olefin copolymer having more than 80wt.% propylene content, a melting point of lower than 150 deg.C, preferably 115 to 150 deg.C, is combined with (B) 0.01 to 0.5wt.%, based on the total composition, of a microfine powder of amorphous silica having 5 to 6mum average particle size, more than 500m<2>/g specific surface area according to the BET method, and less than 150ml/100g oil absorption to give the subject composition which resists creasing and scratching to increase productivity in printing, laminating, packaging or pouch making processes.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polypropylene resin composition for metallized films, and more specifically, the film obtained from it has almost no fish eyes. This invention relates to a polypropylene-based resin composition for a metal-deposited film, which provides a uniform metal-deposited film with no irregularities and excellent metallic luster when gold dust is deposited on the base.

[Conventional technology]

In recent years, metal-deposited films, which are made from plastic films and metals such as aluminum are deposited under vacuum, have been utilized for their excellent decorative properties, gas barrier properties, light blocking properties, etc., and have been used for decorative purposes such as gold and silver thread. Applications have been expanded to areas of mass consumption such as construction, food packaging, etc., and they are now widely used. Polypropylene films are the main type of plastic film, and metallized polypropylene films based on polypropylene films have also been used for the above-mentioned purposes.

However, when metal is deposited on a film obtained from ordinary polypropylene resin, additives such as neutralizing agents, dispersants, slip agents, and antioxidants added to the polypropylene resin migrate to the surface. The wettability of the vapor-deposited surface (metallic surface) becomes poor due to printing and transfer, resulting in decreased adhesion with printing and other films (hereinafter sometimes referred to as printing/laminating properties). This tendency is strong in the case of aluminum, which is a major obstacle in developing new applications.

If we try to eliminate these drawbacks by simply not adding the above additives, since these are already commonly used as essential additives, there are many problems that arise in the production of raw films, such as the following: Occurs in stages. For example, if a dispersant (higher fatty acid salts such as calcium stearate are often used) is not added, fish eyes frequently occur in the film due to poor dispersion of the separately added antiblocking agent. Also, if no slip agent is added,
The slipperiness and anti-blocking properties of the film are extremely reduced.
Wrinkles may appear in the rolled film, or so-called curling bumps may occur where the film roll becomes locally enlarged.
It becomes very difficult to wind the roll into a good shape. These phenomena are caused by propylene-α-, which has low rigidity and high stickiness.
This is particularly noticeable in the case of olefin copolymers, and the more the melting point is lowered to improve low-temperature heat-sealing ability, or the wider and thinner the film is made to improve the efficiency of batch metal vapor deposition, the more noticeable it is. However, even if such a raw film is used, it is not possible to obtain a high-quality metallized polypropylene film, so a dispersant is used to improve printing and laminating properties.

The problem was how to prevent frequent occurrence of fish eyes and poor winding appearance caused by not adding a slip agent or the like.

In the past, several proposals have been made to solve these problems. For example, a metallized polypropylene film based on a film obtained from a composition in which zeolite powder is added to a polypropylene resin has been proposed. (Refer to Special Publication No. 16617/1986). In addition, the present inventors have previously developed a polyolefin resin composition for metal-deposited films in which a specific metal-substituted zeolite is contained in a blend of a specific propylene-α-olefin copolymer and a specific polyethylene. (Unexamined Japanese Patent Publication No. 59-258)
(Refer to No. 29), these were useful for improving the blocking resistance of metal vapor deposition (metal vapor deposition refers to properties such as vapor deposition processability and adhesion of vapor deposited films) films, but the present invention According to their subsequent examination.

There were some defects in the surface condition of the film. The reason for this is that zeolite-based inorganic fillers tend to aggregate, and if a dispersant such as a higher fatty acid salt with excellent dispersion effect is not used, poor dispersion will cause speckled protrusions centered around the filler. This is the occurrence of fish eyes. This fish eye.

Even when metal is deposited on the film, the fish-eye portion remains undeposited, causing uneven deposition.Furthermore, the unevenness of the surface due to the fish-eye results in poor gloss on the deposited surface, and the appearance of the roll is often uneven. This was causing the problem to occur.

In order to eliminate the occurrence of fish eyes, a so-called screen filter is installed at the tip of the extruder.
When the mesh of the pack was made finer, it became more clogged, making driving difficult.

Furthermore, polypropylene powder obtained by using a highly active catalyst, which has become common in the production of polypropylene in recent years, has an average particle size of 50I1 m or more.

Large particles or granules with a particle size of 100 to 500 are also known, but the larger the particle size of polypropylene powder, the worse the dispersion of the inorganic filler. It has become increasingly difficult to provide a polypropylene resin composition for metal-deposited films that does not cause fish eyes on the film and has excellent printing and laminating properties using resin powder.

[Problem to be solved by the invention]

The present invention overcomes the drawbacks of the prior art described above, even in the absence of additives such as higher fatty acid salts.

Furthermore, even when a powder with a large particle size of 50 or more is used as a polypropylene resin, the film obtained from it has fewer fish eyes and has an excellent surface smoothness, so that the deposited film can be uniform. The object is to obtain a metal-deposited polypropylene resin film.

[Means to solve the problem]

As a result of various studies, the present inventors have found that the above problem can be solved by a composition containing a specific crystalline propylene-α-olefin copolymer as a main ingredient and a specific amorphous silica fine powder. invention has been achieved.

The present invention will be explained in detail below.

The present invention provides crystalline propylene-α- having a copolymerization ratio of propylene components of 80% by weight or more and a crystal melting point of 150°C or less.
Mainly composed of olefin copolymer and has an average particle size of 0.5
Amorphous silica fine powder with a specific surface area of 500 I/g or more and an oil absorption of 150 ffiI/100 g or less by the BET method at ~6 t1 m is 0.01 m based on the total amount with the crystalline propylene-α-olefin copolymer. This is a polypropylene-based resin composition for a metal-deposited film, characterized in that the content is 0.5% by weight.

In the crystalline propylene-α-olefin copolymer used in the present invention, the α-olefin component is an α-olefin having 4 or more carbon atoms such as ethylene or butene-1, hexene, and one or more of these and propylene. If the crystalline melting point (hereinafter sometimes referred to as Tm) of the crystalline propylene-α-olefin copolymer exceeds 150°C, the adhesion to the deposited film may decrease when formed into a film, or the non-deposited surface may When used as a sealing surface, heat sealability is poor, which is not preferable.

Here, the crystal melting point (Tag) is the endothermic curve associated with the melting of the crystal obtained by heating 10 μm of a sample at a rate of 10°C/min in a nitrogen atmosphere using a scanning differential calorimeter. This Tm, which refers to the peak temperature, is the peak temperature of crystalline propylene-α-
In the case of olefin copolymers, it decreases as the content of comonomer components increases. Particularly in the case of ethylene-propylene random copolymer, it varies slightly depending on the randomness of the copolymer.

When the ethylene component of the copolymer exceeds approximately 2.5% by weight, the Tm becomes 150°C or less.

Preferred examples of the crystalline propylene-α-olefin copolymer include a crystalline ethylene-propylene random copolymer having an ethylene copolymerization ratio of 2.5 to 10% by weight;
Propylene-butene-1 copolymer with a butene-1 copolymerization ratio of 5 to 20% by weight, an ethylene copolymerization ratio of 0.1
Ethylene-propylene-butene-7% by weight and a copolymerization ratio of butene-1 of 0.3 to 15% by weight (however, the total copolymerization ratio of ethylene and butene-1 is 20% by weight or less)
1 ternary copolymers, among which Tm is 115 to
Particularly preferred is one at 150°C.

Such a copolymer is produced by combining the main component propylene with the comonomer ethylene or α-olefin having 4 or more carbon atoms using a highly active catalyst such as a Ziegler-Natsuta catalyst or a known reduced or supported type catalyst. It can be obtained by random copolymerization using various known methods. In recent years, as mentioned above, large particles or granules have been obtained by using highly active catalysts, and these have become the mainstream.

In addition, as known from Japanese Patent Publication No. 39-1836, etc., propylene is polymerized in the first stage and propylene-ethylene is copolymerized in the second stage, or it is manufactured by multistage polymerization in which these steps are repeated. The Ta
Generally, the main peak exceeds 150°C, but the first peak mentioned above
By copolymerizing in stages, the main peak can be lowered to 150° C. or lower, making it possible to obtain a copolymer suitable for the present invention.

The amorphous silica fine powder used in the present invention has an average particle size of 0.
It has a specific surface area of 5 to 6 μm, a specific surface area of 500 i/g or more by the BET method, and an oil absorption of 150 aQ/100 g or less.

If the average particle size is less than 0.5, it tends to agglomerate and fish eyes occur frequently, and if it exceeds 6, the film surface becomes extremely uneven and the gloss is significantly reduced. Also, BE
If the specific surface area measured by the T method is less than 500 rm2/g, the dispersibility in the copolymer will be poor and fish eyes will occur frequently. Furthermore, if the oil absorption exceeds 150 d 2 /100 g, the dispersibility decreases and fish eyes occur frequently or the screen back becomes clogged, making it difficult to obtain a good deposition film.

Generally commercially available silica fine powder is “Aerosil 2
00'' (manufactured by Nippon Aerosil ■), which has an average particle size of 0.1p or less, manufactured by a dry method, and white carbon silica gel, which is manufactured by a wet method. Although the average particle size, specific surface area, oil absorption amount, etc. range over a very wide range, in the present invention, only the amorphous silica fine powder having the above characteristics shows extremely excellent dispersibility. As a matter of fact, there are very few fish eyes, the deposited film is uniform, and a beautiful deposited film with a metallic luster can be obtained.

The content of the amorphous silica fine powder in the composition is 0.01 to 0.5% by weight, based on the total amount of the crystalline propylene-α-olefin copolymer and the amorphous silica fine powder.

If it is less than 0.01% by weight, the blocking prevention effect will be insufficient, and if it exceeds 0.5% by weight, fish eyes and clogging problems will easily occur, which is undesirable. The range is particularly preferred.

Note that the average particle size of the amorphous silica fine powder in the present invention,
Specific surface area and oil absorption are measured by the following methods.

Average particle size: Based on the Coulter counter method.

Specific surface area: Based on the BET method using N2 adsorption at liquid nitrogen temperature.

Oil absorption: According to JIS K-510119.

The composition according to the present invention may optionally contain an antioxidant,
Additives such as lubricants, anti-blocking agents, inorganic fillers, etc. can be included as appropriate within a range that does not impair the purpose of the present invention. In order to prevent deterioration, fatty acids such as stearic acid and oleic acid, metal salts of fatty acids such as calcium stearate and magnesium stearate, fatty acid amides such as oleic acid amide, erucic acid amide, and stearic acid amide, and other fatty acid forming groups are recommended. It is desirable not to contain derivatives containing such fatty acids.An advantage of the present invention is that these fatty acid derivatives are not required.

Preferred antioxidants are those having a molecular weight of 500 or more, such as tetrakis-[methylene-5-(3',5'-di-monobutyl-4'-hydroxybuenyl)propionate].
etc. (see Japanese Patent Application Laid-Open No. 59-25829), Part 1
Alternatively, two or more of them may be used in combination in an amount of 0.01 to 0.3 parts by weight per 100 parts by weight of the crystalline propylene-α-olefin copolymer.

A preferred inorganic filler is a hydrotalcite fine powder having an average particle size of 3 or less, which has excellent dispersibility and has the effect of neutralizing acidic components contained in the raw polymer. The hydrotalcites mentioned here are
The content of hydrotalcite, which is a hydrous basic carbonate of magnesium and aluminum and may be either a natural product or a synthetic product, is 0.00 parts by weight per 100 parts by weight of the crystalline propylene-α-olefin copolymer. 01 to 0.2 parts by weight, preferably 0.03 to 0.15 parts by weight.

If the following other types of polymers are used in the composition of the present invention within a range that does not impede the purpose of the present invention,
A deposited film with each effect added can be obtained. In other words, when carboxylic acid grafted polypropylene is blended, the adhesion of the deposited film improves, and the amorphous ethylene-α-
When an olefin copolymer, low density polyethylene, etc. are blended, impact resistance is improved. In particular, when 1 to 10 parts by weight, preferably 1 to 4 parts by weight of high-density polyethylene having a density of 0.94 or more is blended into 100 parts by weight of the composition of the present invention,
In this case, the melt flow rate (MI) of high-density polyethylene is particularly preferred because it improves blocking resistance, slip property, etc., and also improves the rigidity of the deposited film.
and the melt flow rate (MFR) of the crystalline propylene-α-olefin copolymer (MI/MFR) was set to 0.
It is preferable to set it to 7 or more (see JP-A No. 59-25829).

What is the method of mixing to obtain the composition according to the invention?

Usually known Henschel mixer, Banbury mixer 2
Any of various kneaders 9 extruders etc. can be used. especially,
Amorphous silica fine powder and other necessary additives are blended with crystalline propylene-α-olefin copolymer powder, mixed in powder form with a mixer, etc., and then further melt-mixed using an extruder etc., Preferably, the composition is in the form of a pellet. In addition, when the other types of polymers mentioned above are blended, they may be blended and mixed at the step of pelletizing one composition, and then pelletized. The pellets of the composition and pellets of other types of polymers may be mixed in pellet form and used.

The method for forming a film using the composition according to the present invention may be either the normal T-die method or the tubular method. It is preferable to form the film under conditions such as rapid cooling below ℃, and the thickness of the obtained film is 1.
Usually it is 1001a or less.

The film thus obtained was subjected to corona discharge treatment and flame treatment on the surface to be deposited according to conventional methods.

A surface treatment such as plasma treatment is performed to activate the surface, and a metal is vacuum-deposited on the activated treated surface to obtain the desired metal-deposited film.

This surface treatment may be performed at an appropriate time for the metal vapor deposited layer, but it is convenient and effective to perform it during film production between film formation and winding. If the film is not subjected to such surface treatment, the adhesion of the deposited film tends to be weak, so it is desirable to treat the film so that the wetting index (measurement method is described later) is 37 dyn/am or more. Vapor deposition may be performed after applying an anchor coating agent such as polyester, polyurethane, or epoxy resin to the surface.

The metal can be vapor-deposited onto the film made of the composition of the present invention using any known method. For example, a raw film roll with the above-mentioned surface treatment is set in a vacuum deposition apparatus equipped with a film feeding section, a vapor deposition section, and a winding section, and the atmospheric pressure inside the apparatus is set to 10-'To
The pressure is reduced to below rr, and a container containing a desired metal such as aluminum or a filament to which the desired metal is attached is heated to melt and evaporate the metal, and the evaporated molecules are continuously vaporized on the surface of the unrolled film. A common method is to wind it up. Recently, a method has been adopted in which the feeding section and the winding section are installed outside the device to enable continuous evaporation, but of course this method is also acceptable. This is also possible by sputtering deposition or ion blating, which utilizes the phenomenon of scattering of the metals that make up the material.

The metals to be vapor-deposited are aluminum and gold.

Examples include silver, copper, nickel, chromium, germanium, selenium, titanium, tin, zinc, etc., but workability 2 reflectance,
Aluminum is preferable from the economical point of view, and the present invention is extremely useful from the viewpoint of preventing a decrease in the wettability index (surface tension) of the aluminum surface. The thickness of the metallized layer typically ranges from tens to hundreds of angstroms.

The most effective method of utilizing the present invention is to obtain an unstretched film from the composition of the present invention, vapor-deposit a metal such as aluminum on one side, and use the other side as a sealant layer. The metallized polypropylene film obtained in this way has almost no fish eyes.
It has a uniform and beautiful metallic luster.

〔Example〕

The present invention will be explained in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The measurement methods and evaluation criteria for the characteristics shown in Examples and Comparative Examples are as follows.

(1) Melt flow rate (MFR) of propylene-α-olefin copolymer: JIS K 6758 (test conditions = 230°C, 2.
(Unit: g/10 min) (2) Melt flow rate (MI) of polyethylene: J
IS K 6760 (Test conditions = 190℃, 2.1
(unit: g/10 minutes) (3) Haze: The film before vapor deposition was measured according to ASTM D 1003.

(4) F of the automatic defect inspection system manufactured by Fish Eye Knife Electric Manufacturing Co., Ltd.
0.0 in the film using an ishEya counter. Fish eyes with nuclei larger than ln*φ were measured. (Unit: 2 pieces/1.000aJ) The more fish eyes there are, the worse the appearance and smoothness of the film.

(5) Wetting index: Measured by the method of JIS K 6758. (Unit: d
yn/1) (6) Printing/laminating property of vapor-deposited surface: The vapor-deposited surface (metal surface) of a film with metal (aluminum) vapor-deposited on one side and the non-vapor-deposited surface (base film surface) are overlapped, and 4.2 kg/ Temperature 4 with a load of 100 cj
After being left in an atmosphere of 0° C. and 95% relative humidity for 72 hours, the wettability index of the vapor-deposited surface is measured. In order to be evaluated as having good printing/laminating properties, the wettability index needs to be 35 or more, preferably 37 or more, and the printing/laminating properties of the vapor-deposited surface were ranked as follows based on this wettability index.

(7) Uniformity of deposited film: The deposited film was visually observed and determined as follows.

O: A smooth and uniformly glossy film is formed. ×: There are fine irregularities on the deposition surface, or spots where no deposited film is present or unevenness is observed.

Those rated as X have many practical problems.

Comparative Example 1 Crystal melting point is 145°C, MFR is 7.0. Average particle size is 12
011m, a crystalline ethylene-propylene random copolymer with an ethylene copolymerization ratio of 4.1% by weight, and an average particle size of 3.3I! 0.15% by weight of amorphous silica fine powder having a specific surface area of 300 rrr/g and an oil absorption of 310 m/100 g based on the total amount with the above copolymer, and further 100 parts by weight of the above copolymer. 0.1 of antioxidant (Iranox 1010 manufactured by Ciba Geigy)
5 parts by weight, 0.1 part of neutralizing agent (calcium stearate)
parts by weight and 0.1 parts by weight of a slip agent (erucic acid amide) were mixed in a Henschel mixer for 2 minutes, and then granulated at 220°C using an extruder with a diameter of 40φ to form pellets. The composition was This pellet has a diameter of 6
23 mm using a 5 φ extruder and a 600 m wide T-die.
Melt extrusion at 0°C, quench with an air knife and cooling roll at 30°C to form a film, immediately apply corona discharge treatment to one side of the film, and roll up to a thickness of 25/jl.
An original film having a wettability index of 41 dyn/as on the treated surface was obtained. Next, this raw film was subjected to aluminum vapor deposition under a vacuum of 10-' Torr using a winding type vacuum evaporation apparatus, and then rolled up to obtain a single-sided vapor-deposited film with a thickness of about 400. . The properties of each film are shown in Table 1.

The obtained original film had a haze of 1.8% and 5 fish eyes/1,000aJ, and therefore had a good winding appearance, but the vapor-deposited film had a speckled appearance. It was non-uniform, and its printing and laminating properties were extremely poor (wetting index was 32 dyn/e11), and it was difficult to put it into practical use as a vapor-deposited film. Note that the adhesion of the deposited film was so weak that it could be easily peeled off with cellophane tape.

Comparative Example 2 A pellet-shaped composition was obtained in the same manner as in Comparative Example 1, except that the neutralizing agent and slip agent were not added. A raw film and a single-sided vapor deposited film were obtained using this composition. The properties of each film are shown in Table 1.

The obtained raw film had an extremely high haze of 2.5% and 120 fish eyes, and the vapor-deposited film had 0 printing/laminating properties on the vapor-deposited surface (wetting index was 38 dyn).
/tx), but the vapor-deposited film had speckled transparent parts around the fish-eye portions that were not vapor-deposited, and the unevenness of vapor-deposition was very noticeable6.
Adhesion of the deposited film was good.

Examples 1-3. Comparative Examples 3 to 9 Except that in Comparative Example 2, amorphous silica fine powder having the characteristics shown in Table 1 was blended in the amount shown in Table 1.
A pellet-like composition was obtained in the same manner as in Comparative Example 2, and using this, a single-sided corona-treated raw film with a thickness of 2511a and a deposited film with a thickness of 350 to 400 mm were prepared in the same manner as in Comparative Example 2.
An aluminum-deposited film was obtained. Table 1 shows the properties of the obtained raw film and vapor deposited film.

As shown in Table 1, the average particle size of the amorphous silica fine powder is 6.
- (Comparative Example 5), when the average particle size is less than 0.5Im (C Comparative Example 6), when the specific surface area is less than 500rd/g (Comparative Example 3.4), the oil absorption is 150+aQ/10
When it exceeds 0 g (Comparative Examples 2 and 7), fish eyes in the film increase, the uniformity of the deposited film is poor, and a good deposited film cannot be obtained.

In addition, even if the amorphous silica fine powder satisfies the characteristic conditions, if the blending amount (content) is outside the range specified by the present invention (Comparative Example 8
, 9) have not yielded good results.

On the other hand, in Examples 1 to 3, there were very few fish eyes in the original film, and therefore the deposited film had excellent uniformity and a very beautiful metallic luster.

From the comparison of Comparative Examples 2 to 9 and Examples 1 to 3, it can be seen that the effects of the present invention are obtained only when the amorphous silica fine powder specified in the present invention is used in a specific amount.

Example 4 Crystal melting point is 137°C, MFR is 6.5. Average particle size is 15
04, a crystalline ethylene-propylene-butene-1 ternary copolymer with an ethylene copolymerization ratio of 2.5% by weight and a butene-1 copolymerization ratio of 5.0% by weight, and an average particle size of 2.0%.
Specific surface area is 70Onf/g at 5μm, oil absorption is 10M/g.
100g of amorphous silica fine powder was blended at 0.2% by weight based on the total amount with the above copolymer, and 10% of the above copolymer was added.
Antioxidant (Irg manufactured by Ciba Geigy) per 0 parts by weight
0.1 part by weight of anox1076) and an average particle size of 1
．． 2. Hydrotalcite powder having a specific surface area of 1 g/rrr in ca was added at each ratio of 0.05 parts by weight.

A pellet-like composition was prepared in the same manner as in Comparative Example 1. This was then formed into a film, and one side was treated with corona discharge to give a thickness of ZSIa and a wettability index of 41d on the treated surface.
An original film of yn/cs+ was obtained. This raw film has a haze of 2.5% and 3 fish eyes/1.0
The roll appearance was good with OOcd.

This raw film was subjected to vacuum deposition in the same manner as in Comparative Example 1,
A single-sided aluminum vapor-deposited film having a thickness of about 400 was obtained. The uniformity of the deposited film of this deposited film was O, and its printing and laminating properties were also ranked 0 (wetting index: 39 dyn/aI), indicating that the deposited film had extremely excellent properties. Note that the deposited film was not peeled off by cellophane tape.

Separately, 100 parts by weight of the above pellets has a density of 0.9
3.60 and MI 10 high density polyethylene pellets.
In this case MI/MFR=1.54)
After mixing in a tumbler μm for 15 minutes, a raw film was formed in the same manner as above, and aluminum was deposited on this to obtain a single-sided deposited film with a thickness of 25p and a deposited film thickness of 400mm. This vapor deposited film.

The uniformity and printing/laminating properties of the deposited film were maintained at the same level as the above-mentioned deposited film (not containing high-density polyethylene), and the slip property of the film surface (measured using the method of ASTM 01894-63) was maintained. The kinetic wear coefficient) was 0.85 for the vapor-deposited film, while it was 0.85 for the vapor-deposited film.
．． 55, which was extremely good. The degree of this slip property is determined by the amount of high-density polyethylene added in the normal case (without the amorphous silica fine powder used in the present invention).
This is a level corresponding to the slip property when the amount is 8 parts by weight, and the effect of adding high-density polyethylene to the composition according to the present invention is large.

The following margin [Effects of the invention] The composition according to the present invention has a characteristic crystalline propylene-α-
By containing a specific amorphous silica fine powder mainly composed of an olefin copolymer, the metallized film obtained using the film as a base has extremely few fish eyes and excellent uniformity, making it easy to roll. As a result, it is possible to obtain a vapor-deposited film with excellent productivity that can be rolled in a wide and long length, which is unprecedented in the past.
In other words, wrinkles and scratches are less likely to occur during printing, laminating, packaging, and bag-making processes, improving productivity.Moreover, the deposition surface is uniform, resulting in a beautiful metallic luster, and is easy to print and laminate. Since it has good properties, it can be used for a wide range of purposes such as packaging and decoration.

Claims (1)

[Scope of Claims] 1. Mainly composed of a crystalline propylene-α-olefin copolymer with a propylene component copolymerization ratio of 80% by weight or more and a crystal melting point of 150°C or less, and an average particle size of 0.5 to 6 μm.
m, the amorphous silica fine powder with a specific surface area of 500 m^2/g or more and an oil absorption of 150 ml/100 g or less by the BET method is 0.01 to 0.01 m based on the total amount with the crystalline propylene-α-olefin copolymer. A polypropylene resin composition for a metallized film, characterized in that it contains 0.5% by weight. 2. The polypropylene resin composition for metal deposition according to claim 1, wherein a crystalline ethylene-propylene copolymer having a crystalline melting point of 115 to 150°C is used as the crystalline propylene-α-olefin copolymer. 3. The polypropylene resin composition for metal deposition according to claim 1, wherein a crystalline propylene-butene-1 copolymer having a crystalline melting point of 115 to 150°C is used as the crystalline propylene-α-olefin copolymer. 4. The polypropylene system for metal deposition according to claim 1, wherein a crystalline ethylene-propylene-butene-1 terpolymer having a crystalline melting point of 115 to 150°C is used as the crystalline propylene-α-olefin copolymer. Resin composition. 5. The polypropylene resin composition for metal deposition according to any one of claims 1 to 4, wherein the crystalline propylene-α-olefin copolymer has an average particle size of 50 to 1000 μm.