JPH0655698A - Composite film and manufacture thereof - Google Patents

Abstract

PURPOSE:To pack an article at high speed by an automatic packaging machine for overlapping by using a composite film having excellent sliding properties, releasability and transparency. CONSTITUTION:A polymer layer including a thermal adhesive olefin polymer, dimethyl polysiloxane, and carboxyl modified silicone and/or polyether modified silicone is laminated on at least one surface of the base-material film layer of polypropylene, etc., and oriented, thus acquiring a composite film. A propylene copolymer such as an ethylene-propylene copolymer, an ethylene-propylene- butene-copolymer, etc., is contained in the thermal adhesive olefin polymer. 0.3-2 pts.wt. dimethyl polysiloxane is comprised to the 100 pts.wt. thermal adhesive olefin polymer while carboxyl modified or polyether modified silicone B is contained to dimethyl polysiloxane A at the ratio of A/B=100/20-100 (a weight ratio) in a coating layer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composite film suitable for overlapping packaging and a method for producing the same.

[0002]

2. Description of the Related Art As a packaging material, various films, particularly polypropylene film and polyethylene terephthalate film, which are excellent in properties such as transparency and rigidity, are used. Furthermore, in addition to gas barrier properties against oxygen gas and water vapor, a film coated with a vinylidene chloride copolymer that has heat sealability is used as a film for overlapping packaging of various products such as foods, cigarettes and cassette tapes. Has been done.

On the other hand, a stretched film such as a biaxially stretched polypropylene film has poor heat sealability. Therefore, in the base film layer such as polypropylene film,
A laminated film obtained by laminating and stretching an olefin polymer layer having a heat-sealing property is also under study. But,
The laminated film in which the olefin polymer layer is laminated has inferior mechanical properties to an automatic wrapping machine for overlapping in a high-speed packaging application, for example, at a high speed of 250 pieces / minute or more. That is, when the laminated film is used in the automatic wrapping machine for overlapping, heat and pressure simultaneously act, so that the slipperiness with respect to the metal guide plate and the releasability are significantly reduced. Therefore, the overwrapping cannot be performed at high speed, and the packaging workability is deteriorated.

In order to improve the slipperiness of the film, an anti-blocking agent consisting of inorganic fine powder such as silica, alumina, synthetic zeolite or organic fine powder such as polyethylene; adding mineral or petroleum wax to the olefin polymer. (For example, Japanese Patent Laid-Open No.
No. 71830, etc.).

However, even if such an additive is added,
In the bonding step by thermocompression in which heat and pressure act simultaneously, the releasability from the metal guide plate is poor. for that reason,
Cannot be packaged at a speed of 250 pieces / minute or more.

Therefore, in order to improve the releasability of the film, a method is known in which a releasing agent such as silicone oil or polydimethylsiloxane gum is added (JP-A-59-1).
No. 33050). However, these release agents have poor compatibility with polyolefins, and thus reduce the transparency of the film. Therefore, when used for overlapping packaging, the contents cannot be visually recognized clearly, and the contents look cloudy, which lowers the commercial value.

[0007]

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a composite film having excellent transparency and capable of packaging articles at high speed.

Another object of the present invention is to provide a composite film which is excellent in slipperiness, releasability and transparency and which is capable of packaging articles at high speed by an automatic wrapping machine for overlapping.

Still another object of the present invention is to provide a method for producing a composite film having the above-mentioned excellent properties.

[0010]

The present inventor, as a result of extensive studies to achieve the above object, formed a heat-adhesive olefin polymer layer containing dimethylpolysiloxane and a specific modified silicone in a specific ratio on the surface of a base film. Then, surprisingly, it was found that the advantages of dimethylpolysiloxane and modified silicone are effectively exhibited, and that a composite film having excellent slipperiness, releasability and transparency, and high speed packaging suitability is obtained, and the present invention is completed. did.

That is, the present invention provides (1) a coating layer containing (2) a heat-adhesive olefin-based polymer, dimethylpolysiloxane, and carboxyl-modified or polyether-modified silicone on at least one surface of the substrate film layer. A laminated film, in which dimethylpolysiloxane 0.
Dimethylpolysiloxane A containing 3 to 2 parts by weight
And carboxyl-modified or polyether-modified silicone B
A composite film having a ratio of A / B = 100/20 to 100 (weight ratio) is provided.

Further, according to the present invention, (1) at least one surface of the base film layer contains (2) 0.3 to 2 parts by weight of dimethylpolysiloxane based on 100 parts by weight of the heat-adhesive olefin polymer. In addition, A / B = 100/20 to 100 (weight ratio) of carboxyl-modified or polyether-modified silicone B with respect to dimethylpolysiloxane A
Also provided is a method for producing a composite film, which comprises laminating polymer layers containing the same in the following proportions.

Examples of the polymer constituting the base film layer include olefins such as polyethylene, ethylene-ethyl acrylate copolymer, ionomer, polypropylene, ethylene-propylene copolymer and poly-4-methylpentene-1. -Based polymers; vinyl alcohol-based polymers such as polyvinyl alcohol and ethylene-vinyl alcohol copolymers; polyvinyl chloride; vinylidene chloride-vinyl chloride copolymers, vinylidene chloride-based polymers such as vinylidene chloride-acrylonitrile copolymers; polystyrene, styrene -Styrene polymers such as acrylonitrile copolymer and styrene-acrylonitrile-butadiene copolymer; polyesters such as polyethylene terephthalate and polybutylene terephthalate; nylon 6, nylon 11 Nylon or nylon such as nylon 12, nylon 66, nylon 610, nylon 612, nylon 6/66, nylon 66/610, nylon 6/11; polyacrylonitrile; polycarbonate; polyimide; polyphenylene oxide; polysulfone; polyparaxylene; polyamideimide Polyester imide and the like.

The base film layer is preferably composed of an olefin polymer (especially polypropylene polymer) and a polyester (especially polyethylene terephthalate). A preferable substrate film layer is composed of a polypropylene-based polymer which is excellent in transparency, rigidity and packaging suitability.

The polypropylene-based polymer is preferably a crystalline polypropylene-based polymer. The propylene-based polymer may be a copolymer having propylene as a constituent component, for example, a copolymer with ethylene, butene, an α-olefin such as 1,3-methylpentene, but a propylene homopolymer is preferable. .

The propylene-based polymer has an isotactic index (II) of 90% or more, preferably 9
It is preferably 5% or more, and more preferably 96% polypropylene. A polypropylene-based polymer film having such an isotactic index (II) is suitable for automatic packaging because it runs straight without curling when the film runs.

The intrinsic viscosity [η] of the propylene-based polymer is usually 0.5 to 7 dl / g, preferably 1 to
It is about 5 dl / g.

The base film layer may be a single layer film or a laminated film in which two or more kinds of polymer layers are laminated. The thickness of the base film layer is not particularly limited, and for example, the thickness is 1 to 250 μm, preferably 5 to 10
It is about 0 μm.

Further, the base film layer contains various additives such as an antioxidant, as long as the high speed wrapping property is not impaired.
Stabilizers such as UV absorbers and heat stabilizers; polyoxyethylene alkyl amines, quaternary ammonium salts, cations such as hydantoin derivatives, sulfuric acid derivatives, alkyl sulfonates, anions such as phosphoric acid derivatives, polyhydric alcohols , An ester of a polyhydric alcohol such as glycerin and a fatty acid, an adduct of a fatty acid ester and an alkylene oxide such as ethylene oxide, a nonionic agent such as polyoxyethylene alkylphenol, and an antistatic agent such as an amphoteric antistatic agent such as alkylbetaine; Crystal nucleus growing agent; styrenic resin, terpene resin, petroleum resin, dicyclopentadiene resin, coumarone resin such as coumarone indene resin, phenolic resin, hydrocarbon polymer such as rosin and its derivatives and hydrogenated resins thereof Plasticizer; filler; stearic acid Acid amides such as amides, oleic acid amides, erucic acid amides, and alkylenebisstearic acid amides, higher fatty acids and their salts, higher fatty acid esters, natural waxes such as minerals and plants, and synthetic waxes such as polyethylene; Fine powder such as powdered silica; dyes and pigments may be included.

In particular, the base film layer preferably contains the above-mentioned hydrocarbon polymer such as hydrogenated terpene resin, hydrogenated petroleum resin and dicyclopentadiene resin in order to strengthen the rigidity of the film. The content of the hydrocarbon polymer is, for example, 1 to 30% by weight, preferably about 5 to 15% by weight.

The film containing an antistatic agent together with the above-mentioned hydrocarbon polymer is useful for preventing electrostatic adhesion of the film to the packaging machine during the packaging operation, and further has high speed packaging suitability. improves. The content of the antistatic agent is
For example, 0.01 to 5% by weight, preferably 0.1 to 2.
It is about 5% by weight. Further, the base film layer contains wax, for example, 0.01 to 5% by weight, and preferably 0.1.
The content may be about 2.5 wt%.

A coating layer containing a heat-adhesive olefin polymer, dimethylpolysiloxane, and modified silicone is laminated on one or both sides of the base film layer.

The heat-adhesive olefin-based polymer contains, for example, homopolymers of olefins such as ethylene, propylene, butene-1,3-methylpentene-1,4-methylpentene, and these olefins as constitutional units. Copolymers and the like are included.

The preferred olefin-based polymer is a polymer having heat-sealing property, for example, ethylene-propylene copolymer, ethylene-butene-1 copolymer, ethylene-propylene-butene-1 copolymer, ethylene-3-.
Methylpentene-1 copolymer, ethylene-propylene-
3-methylpentene-1 copolymer, ethylene-4-methylpentene-1 copolymer, ethylene-propylene-4-
Methylpentene-1 copolymer, ethylene-butene-1-
Examples thereof include olefin-based copolymers such as 3-methylpentene-1 copolymer. The olefin-based copolymer may be a random copolymer, a block copolymer or the like, and a random copolymer is usually used. Particularly preferred olefin-based polymers include propylene-based copolymers containing propylene as a constituent, such as ethylene-propylene copolymers and ethylene-propylene-butene-1 copolymers. Among them, ethylene-propylene-
Butene-1 copolymer is preferred.

In the ethylene-propylene-butene-1 copolymer, the ethylene content is, for example, 0.3 to 10% by weight, preferably 0.5 to 5.0% by weight, and the butene-1 content is 1 to 50% by weight. %, Preferably about 3 to 25% by weight.

The olefin-based polymer has a heat-sealing property in the hot-pressing bonding process required for high-speed overlapping packaging, particularly a low-temperature heat-sealing property. However, as described above, when the coating layer is composed of the olefin polymer alone, the sliding property with respect to the metal guide plate and the like is not good in the high-speed overlapping packaging machine in which heat and pressure act.

On the other hand, when a coating layer is formed by adding dimethylpolysiloxane and carboxyl-modified silicone and / or polyether-modified silicone to the above-mentioned olefin-based polymer, in the heat-pressure bonding step of the high-speed overlapping packaging machine. A composite film having high transparency as well as slipperiness and releasability with respect to a metal guide plate and the like can be obtained. Such a composite film can smoothly carry out the overwrap packaging of articles at a high speed of 250 pieces / minute or more.

More specifically, as described above, the dimethylpolysiloxane contained in the coating layer reduces the transparency of the film. On the other hand, when the modified silicone is added,
Although the decrease in transparency is small, the releasability from the heater bar is poor in the process of bonding by thermocompression and packaging. Therefore, it is difficult to perform the overlapping packaging at a high speed. However, when a specific amount of dimethylpolysiloxane is added to the heat-adhesive olefin-based polymer, and when dimethylpolysiloxane and the modified silicone are used in a specific ratio, surprisingly, the advantages of both are effectively exhibited and the transparency is improved. It is possible to obtain a film having high properties, slipperiness and releasability.

The type of dimethylpolysiloxane is not particularly limited, and for example, the viscosity at 25 ° C. is 100 to 5 × 10 ^6.
Centistokes, preferably 1 × 10 ⁴ to 2 × 10 ⁶
Centistokes, more preferably 8 × 10 ⁴ to 2 ×
Polydimethylsiloxane of about 10 ⁶ centistokes can be used. The dimethylpolysiloxane may be gum-like. The average molecular weight of the gum-like dimethylpolysiloxane is usually 230,000 or more.

In the dimethylpolysiloxane, a part of the methyl group may be substituted with a phenyl group, etc. within a range not impairing the slip property and the releasing property.

As the modified silicone, a carboxyl-modified silicone and / or a polyether-modified silicone that compatibilizes the dimethylpolysiloxane with a heat-adhesive olefin polymer to improve transparency is used.
The substitution position of the organic group in the modified silicone may be a side chain, both ends, or one end, and may be block-polymerized with the silicone unit of the main chain. A particularly preferred modified silicone for improving transparency is a side chain modified silicone having an organic group in a side chain.

The viscosity and the degree of polymerization of the modified silicone can be selected in a wide range similarly to the above-mentioned dimethylpolysiloxane. The viscosity of the modified silicone is not particularly limited, but is, for example, about 100 to 10,000 centistokes, preferably about 500 to 5,000 centistokes.

In the present invention, the ratio of dimethylpolysiloxane to the heat-adhesive olefin polymer has a great influence on the properties of the composite film. The ratio is 0.3 to 2 parts by weight of dimethylpolysiloxane, preferably 0.1 to 100 parts by weight of the heat-adhesive olefin polymer.
4 to 1.5 parts by weight, more preferably 0.4 to 1 part by weight. When the content of dimethylpolysiloxane is less than 0.3 parts by weight, the slipperiness and releasability of the film are deteriorated, and when it exceeds 5 parts by weight, poor sealing tends to occur.

The proportion of dimethylpolysiloxane A and carboxyl-modified or polyether-modified silicone B also affects the properties of the composite film. A / B = 100/2
0-100 (weight ratio), preferably 100 / 25-60
(Weight ratio). When the modified silicone is added in such a ratio, high slip property due to dimethylpolysiloxane during high-speed overlapping packaging by thermocompression bonding,
The transparency can be improved while maintaining the releasability.

The coating layer is made of another organopolysiloxane, for example, polyaryl siloxane such as polydiphenyl siloxane, polyalkylaryl siloxane such as methylphenyl polysiloxane, alcohol-modified silicone, alkyl-modified silicone, higher fatty acid ester-modified silicone. , Higher alkoxy-modified silicone, hydrophilic group-modified silicone, epoxy-modified silicone, amino-modified silicone and the like.

The coating layer may contain various additives which can be added to the base film layer. Especially 100 ℃
It is useful to add an antiblocking agent, wax, etc. in order to improve the slipperiness under the following low temperature and low load. As the anti-blocking agent, fine powder such as fine powder silica, particularly inorganic fine powder having an average particle size of about 1 to 5 μm, organic fine powder such as acrylic resin, silicone resin, and fluorine resin can be used. As the acid amide, an acid amide such as stearic acid amide or erucic acid amide, a fatty acid ester, or a natural or synthetic wax such as carnauba wax can be used. The use of the anti-blocking agent and / or the wax, in combination with the action of the dimethylpolysiloxane and the like, allows the smooth overlapping packaging to be performed at a higher speed. The antiblocking agent and the amount of wax added are, for example,
0.05 to 1% by weight, preferably 0.1 to 0.7% by weight
It is a degree.

The thickness of the coating layer can be selected within a range that does not impair the properties of the film, and is, for example, 0.1 to 5 μm, preferably 0.5 to 2.5 μm, and more preferably 0.8 to.
It is about 1.5 μm.

The composite film composed of the base film layer and the coating layer may be unstretched, but is preferably stretched. The stretched film may be a uniaxially stretched film, but is preferably a biaxially stretched film, particularly a film containing a biaxially stretched polypropylene film layer. Moreover, the stretched film may be heat-treated, if necessary.

The surface of the composite film may be subjected to a conventional surface treatment such as corona discharge treatment, flame treatment and plasma treatment, if necessary.

In the composite film of the present invention, (1) a base film layer, and (2) a polymer layer containing (2) a heat-adhesive olefin-based polymer, dimethylpolysiloxane and modified silicone in the above proportions is laminated. Can be obtained by More specifically, the composite film can be obtained by a dry lamination method or a coextrusion molding method.
The preferred method is the coextrusion method.

In the dry laminating method, the surface of at least one of (1) a base film layer and (2) a polymer layer containing a heat-adhesive olefin polymer, dimethylpolysiloxane and modified silicone is coated with, for example, titanium. It can be carried out by treating with an anchor coating agent such as a system-based anchor coating agent, a polyethyleneimine-based anchor coating agent, or a urethane-based anchor coating agent, and laminating. In the dry laminating method, stretched films can be used as the (1) base film layer and the (2) polymer layer.

In the coextrusion molding method, (1)
It can be obtained by co-extruding the polymer composition forming the base film layer and (2) the polymer composition containing the heat-adhesive olefin polymer, dimethylpolysiloxane and modified silicone. The extruded composite film is preferably subjected to a stretching step.

The coextrusion molding can be carried out according to a conventional method. For example, in an extruder equipped with a T die, a ring die, etc., (1) a polymer composition constituting the base film layer, and (2) a polymer containing a heat-adhesive olefin polymer, dimethylpolysiloxane and modified silicone. The composition and the composition are separately charged and melt-extruded into a die by an extruder. In the flow path in the die, the layers of the polymer compositions (1) and (2) are merged and laminated, and the composite film is obtained by melt extrusion from the die and cooling.

Stretching of the composite film can be carried out in the T-die method after cooling the composite film extruded from the die, and in the inflation method, it can be carried out together with melt extrusion from the die.

The stretching method may be a conventional stretching method, for example,
Examples include roll stretching, tenter stretching, tube stretching, and a stretching method combining these. The draw ratio can be appropriately set according to the desired characteristics of the film, and at least one draw ratio is, for example, 4 to 10 times, preferably 6 to
It is about 10 times.

Various coating layers and laminate layers may be formed on the composite film of the present invention depending on the type of base film layer and the intended use. For example, when enhancing the oxygen gas barrier property, the composite film may be coated or laminated with a vinyl alcohol-based polymer, and in order to enhance the barrier property against carbon dioxide gas and water vapor including oxygen gas, a vinylidene chloride polymer is coated. Alternatively, they may be laminated. Further, a slipping layer or the like may be formed on the composite film.

Preferred embodiments of the present invention are as follows.

(A) On at least one surface of the polypropylene film layer, a propylene-based copolymer having heat sealability (for example, at least one of an ethylene-propylene copolymer and an ethylene-propylene-butene-1 copolymer). A composite film in which a coating layer containing a propylene-based copolymer), dimethylpolysiloxane, and carboxyl-modified or polyether-modified silicone is laminated and biaxially stretched.

(B) A composite film in which the polypropylene film layer contains a hydrocarbon polymer and / or an antistatic agent.

(C) The propylene-based copolymer has an ethylene content of 0.5 to 5% by weight and a butene-1 content of 3 to 25% by weight.
A composite film of the ethylene-propylene-butene-1 copolymer of.

(D) A composite film in which the coating layer contains an antiblocking agent, preferably a fine powdery antiblocking agent.

The present specification also discloses an overlapping method in which the composite film is used to package articles at a rate of 250 pieces / minute or more.

[0053]

INDUSTRIAL APPLICABILITY The composite film of the present invention is excellent in transparency because the coating layer contains the heat-adhesive olefin-based polymer, dimethylpolysiloxane, and the specific modified silicone in a specific ratio, and thus the composite film can form an article. Can be packaged at high speed.

Further, the composite film has high slipperiness, releasability and antistatic property. Therefore, articles can be packaged at high speed by the automatic packaging machine for overlapping.

According to the manufacturing method of the present invention, a composite film having the above-mentioned excellent properties can be obtained.

[0056]

EXAMPLES The present invention will be described in more detail based on the following examples.

Example 1 Raw material (A) for base polymer layer and raw material (B) for coating layer
As (C), a mixture having the following composition was used.

Raw material (A) for the base polymer layer: Isotactic polypropylene (manufactured by Sumitomo Chemical Co., Ltd., trade name FS2011D, melt index: 2.0 g / 10)
90 parts by weight (230 ° C., melting point 165 ° C.), 10 parts by weight of petroleum resin, 1.0 part by weight of a mixture of acylamine / ethylene oxide adduct and monoglyceride stearate, and 0.1 part by weight of stearic acid amide. .

Raw material (B) for the coating layer: ethylene-propylene-butene-1 random copolymer (Sumitomo Chemical Co., Ltd.)
Made, brand name WF715N) 100 parts by weight, average particle size 3μ
m fine powder silica 0.4 part by weight, dimethylpolysiloxane (viscosity 800,000 centistokes) 0.5 part by weight and polyether modified silicone (Toshiba Silicone Co., Ltd.)
Manufactured by TSF4445, viscosity 800 centistokes) 0.2 part by weight of a mixture.

Raw material (C) for the coating layer: ethylene-propylene-butene-1 random copolymer (Sumitomo Chemical Co., Ltd.)
Manufactured by WF715N, 100 parts by weight and 0.3 parts by weight of finely divided silica having an average particle size of 3 μm.

The raw materials (A), (B), and (C) are supplied to an extrusion molding machine equipped with a T die, and 220 to 230 are supplied.
Coextrusion molding was carried out at a temperature of ° C to prepare a sheet of 3 types and 3 layers having a layer structure of B / A / C. The obtained sheet is
Stretched 6 times in the longitudinal direction with a roll at 125 ° C, then 16
After stretching 10 times in the width direction at a temperature of 0 ° C.
Heat treatment was performed for 0 seconds, and the surface of the layer C was subjected to corona discharge treatment to prepare a composite film of 3 layers of 3 types. The thickness of the obtained composite film was 23 μm (A layer has a thickness of 20 μm, and B and C layers have a thickness of 1.5 μm).

Example 2 Instead of the raw material (B) for the coating layer of Example 1, ethylene-
Propylene copolymer (Sumitomo Chemical Co., Ltd., trade name F
L6711N) 100 parts by weight, 0.3 parts by weight of finely divided silica having an average particle size of 3 μm, 0.5 parts by weight of polydimethylsiloxane gum having a degree of polymerization of 4500, and carboxyl-modified silicone oil (Toshiba Silicone Co., Ltd., trade name TSF).
4771, viscosity 1500 centistokes) 3 as in Example 1 except using 0.15 parts by weight of the mixture.
A seed 3 layer composite film was prepared.

Example 3 The same procedure as in Example 1 was repeated except that the amount of dimethylpolysiloxane as the raw material (B) for the coating layer in Example 1 was 1.5 parts by weight and the amount of the polyether-modified silicone oil was 0.6 parts by weight. hand,
A composite film of three types and three layers was produced.

Examples 4 and 5 The amount of the carboxyl-modified silicone oil as the raw material (B) for the coating layer of Example 2 was 0.3 parts by weight (Example 4) and 0.45 parts by weight (Example 5). ), A composite film of 3 layers of 3 types was prepared in the same manner as in Example 2.

Comparative Example 1 Instead of the raw material (B) for the coating layer of Example 1, 100 parts by weight of the ethylene-propylene-butene-1 random copolymer used in Example 1 and a fine powder having an average particle size of 3 μm. Silica 0.
3 parts by weight, and dimethylpolysiloxane (viscosity 100
Ten thousand centistokes) A three-kind three-layer composite film was prepared in the same manner as in Example 1 except that 0.5 part by weight of the mixture was used.

Comparative Example 2 Instead of the raw material (B) for the coating layer of Example 1, 100 parts by weight of the ethylene-propylene-butene-1 random copolymer used in Example 1 and a fine powder having an average particle size of 3 μm. Silica 0.
Example 1 except that a mixture of 3 parts by weight and 0.5 parts by weight of polydimethylsiloxane gum having a degree of polymerization of 4500 was used.
A three-kind three-layer composite film was prepared in the same manner as in.

Comparative Example 3 Instead of the raw material (B) for the coating layer of Example 1, 100 parts by weight of the ethylene-propylene-butene-1 random copolymer used in Example 1, fine powder having an average particle size of 3 μm. Silica 0.
3 parts by weight, and the polyether-modified silicone used in Example 1 (manufactured by Toshiba Silicone Co., Ltd., trade name TSF44)
45, viscosity 800 centistokes) A composite film of 3 types and 3 layers was prepared in the same manner as in Example 1 except that 0.5 part by weight of the mixture was used.

Comparative Examples 4 to 6 The addition amount of the carboxyl-modified silicone of the raw material (B) of Example 2 was 0.05 parts by weight (Comparative Example 4), 1.0 parts by weight (Comparative Example 5), and 3.0. A three-kind, three-layer composite film was produced in the same manner as in Example 2 except that the weight part (Comparative Example 6) was used.

Comparative Examples 7 to 9 The amount of dimethylpolysiloxane as the raw material (B) of Example 1 was 0.2 parts by weight (Comparative Example 7), 3.0 parts by weight (Comparative Example 8), and 5.0 parts by weight. A 3-type, 3-layer composite film was produced in the same manner as in Example 1 except that the weight part (Comparative Example 9) was used.

Comparative Example 10 An isotactic polypropylene biaxially stretched film (thickness 20 μm) was coated on one side with an anchor coating agent containing chlorinated polypropylene, and then as a lubricant with respect to 100 parts by weight of vinylidene chloride copolymer. A coating agent containing 0.3 parts by weight of finely powdered silica and 0.3 parts by weight of an antistatic agent was applied on the anchor coat layer at a solid content of 1.5 g / m ² to prepare a coating film.

Then, the high-speed overlapping packaging suitability and transparency of the composite films obtained in Examples and Comparative Examples were evaluated as follows.

High-speed overlapping packaging suitability: A carton containing 20 cigarettes is automatically wrapped by an automatic wrapping machine (manufactured by Tokyo Automatic Machinery Co., Ltd., W323 type).
Was used to automatically package each film. The packaging is 20
At a packaging speed of 250 pieces / min under conditions of ℃ and 55% RH,
It was packaged for 2 minutes and the packaging suitability was evaluated according to the following criteria.

(1) The number of packages that can be packaged before the machine is stopped because the film is clogged in the packaging machine (2) Adhesiveness of the seal portion of the packaging body after completion of packaging Excellent: Sealing Impossible: Sealing Not done Transparency: According to JIS K-6714, four films were stacked and a haze value was measured using a haze meter (manufactured by Toyo Seiki Seisakusho). Regarding the transparency of the film, in the case of overlapping packaging, if the haze value is 10 or less, the content looks clear, and if the haze value is 14 or more, the content looks cloudy and the commercial value is lowered.

The results are shown in the table.

[0075]

[Table 1] As is clear from the table, the composite films obtained in Examples 1 to 5 are excellent in packaging suitability, and even if they are packaged at a high speed of 250 pieces / minute, no trouble occurs and they are smoothly packaged by heat sealing. did it.

On the other hand, the films obtained in Comparative Example 1, Comparative Example 2, Comparative Example 4 and Comparative Examples 8 to 10 had poor transparency and the contents looked cloudy. The composite film obtained in Comparative Example 3 had poor slipperiness with respect to the heater bar, was immediately clogged in the automatic packaging machine, and could not be continuously and automatically packaged. Further, the composite film of Comparative Example 5 was inferior in high-speed wrapping suitability, the machine stopped due to rotation of 30 wrappings, and the composite film of Comparative Example 6 could not be automatically wrapped.

Furthermore, the composite film of Comparative Example 7 was inferior in high speed wrapping suitability, and the machine stopped after rotating 20 pieces of the film. Further, the composite film of Comparative Example 8 had a weak sealing strength after packaging and was inferior in sealing property, and the composite film of Comparative Example 9 could not seal the seal portion.

Claims (4)

[Claims] 1. A film in which a coating layer containing (2) a heat-adhesive olefin-based polymer, dimethylpolysiloxane, and carboxyl-modified or polyether-modified silicone is laminated on at least one surface of a base film layer. In addition, 0.3 to 2 parts by weight of dimethylpolysiloxane is included with respect to 100 parts by weight of the heat-adhesive olefin-based polymer, and the ratio of dimethylpolysiloxane A and carboxyl-modified or polyether-modified silicone B is A / B. =
The composite film which is 100 / 20-100 (weight ratio). 2. The composite film according to claim 1, wherein the base film layer is made of polypropylene, and the film is stretched. 3. The composite film according to claim 1, wherein the heat-adhesive olefin-based polymer is at least one propylene-based copolymer of ethylene-propylene copolymer and ethylene-propylene-butene-1 copolymer. 4. A dimethylpolysiloxane containing (1) 0.3-2 parts by weight of dimethylpolysiloxane with respect to 100 parts by weight of a heat-adhesive olefin-based polymer on at least one surface of a base film layer. Carboxyl-modified or polyether-modified silicone B A /
The manufacturing method of the composite film which laminates the polymer layer which contains B = 100 / 20-100 (weight ratio).