KR101664584B1 - Manufacturing method of polypropylene resin composition for higher shrinkage film - Google Patents

Abstract

In a polypropylene resin composition for a shrinkable film containing a propylene-ethylene-1-butene random copolymer, in order to improve the workability of the prior art, the problem of dispersion during the mixing of an elastomer is solved and a shrinkable film A method for producing a polypropylene resin composition is disclosed. The present invention relates to (a) 70 to 89% by weight of a crystalline propylene-ethylene-1-butene random copolymer prepared from propylene, ethylene and 1-butene as raw materials and introduced into a mixer in a polymerization reactor; (b) 10 to 25% by weight of an elastomer prepared in the same polymerization reactor as the raw material (a) and introduced into the mixer; (c) 1 to 5% by weight of a mixed resin of low density polyethylene and linear low density polyethylene; (d) 0.01 to 0.5 parts by weight of a slip agent based on 100 parts by weight of the total of the components (a) to (c); And (e) 0.01 to 0.5 parts by weight of an anti-blocking agent per 100 parts by weight of the total of the components (a) to (c) in a mixer and extruding the mixture with an extruder to produce a polypropylene resin composition.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for producing a polypropylene resin composition,

The present invention relates to a method for producing a polypropylene resin composition, and more particularly to a polypropylene resin composition excellent in low temperature heat sealing property.

Currently, the shrink film is widely used for shrink packaging such as yogurt, cup noodles, and stationary products. Such a shrink film can be obtained by molding by double bubble type inflation method simultaneous biaxial stretching in the longitudinal direction and the transverse direction.

Such a resin for a shrink film has conventionally used a propylene-ethylene-1-butene random copolymer resin, and the raw material is excellent in biaxial stretchability such as bubble stability, bubble burst, film thickness deviation, and transparency. However, when the propylene-ethylene-1-butene random copolymer resin is used alone, it is poor in softness. Therefore, when shrink-wrapping is used, it is limitedly used for packaging small articles such as yogurt, stationary, There is a disadvantage that there is a limit to high-speed packaging because the heat-sealing composition is lowered.

In order to solve this problem, a method of adding an elastomeric product to an extruder in the production process has been proposed, but a problem of poor product uniformity due to a problem of dispersion failure has been raised.

Korean Patent Registration No. 0783554 discloses a polypropylene resin for a biaxially stretched shrink film prepared by adding an amorphous propylene-1-butene copolymer to a polypropylene random copolymer using a propylene-ethylene-1-butene terpolymer There is a problem such as non-uniformity in shrinkage due to dispersion failure of the elastomer product added to the extruder and unevenness of transparency of the surface.

Korean Patent Publication No. 0745323 discloses a polypropylene resin composition for a shrink film having improved shrinkability and transparency by including a propylene-1-butene copolymer in a crystalline ethylene-propylene-1-butene terpolymer, There is a limitation in the shrink packaging of the large-sized product due to the low quality, and there is a limit to the high-speed packaging due to the low-temperature heat sealing composition.

U.S. Patent No. 5,888,640 discloses a polypropylene resin using a propylene-ethylene copolymer or a propylene-ethylene-1-butene terpolymer in which a syndiotactic polypropylene resin using metallocene is used to improve shrinkage properties Although the polypropylene resin composition has a somewhat low shrinkage rate, the syndiotactic polypropylene resin has a high melting temperature and thus has a limitation in improving the shrinkage ratio.

Disclosure of the Invention The present invention has been conceived to solve the above problems, and it is an object of the present invention to solve the problem of dispersibility in the mixing of an elastomer in order to improve the workability in a polypropylene resin composition for a shrinkable film containing a propylene- And to provide a method for producing a polypropylene resin composition for a shrinkable film suitable for large-sized shrinkable packaging and high-speed packaging.

In order to solve the above problems, the present invention provides a method for producing a polypropylene resin composition by extruding the following components in a mixer and an extruder.

(a) 70 to 89% by weight of a crystalline propylene-ethylene-1-butene random copolymer prepared from propylene, ethylene and 1-butene as raw materials and introduced into a mixer in a polymerization reactor;

(b) 10 to 25% by weight of an elastomer prepared in the same polymerization reactor as the raw material (a) and introduced into the mixer;

(c) 1 to 5% by weight of a mixed resin of low density polyethylene and linear low density polyethylene;

(d) 0.01 to 0.5 parts by weight of a slip agent based on 100 parts by weight of the total of the components (a) to (c); And

(e) 0.01 to 0.5 parts by weight of an anti-blocking agent per 100 parts by weight of the components (a) to (c).

The crystalline propylene-ethylene-1-butene random copolymer contains 1 to 10 mol% of ethylene and 1 to 10 mol% of 1-butene in the propylene component, and has a melt index (230 DEG C, 2.16 kg load) / 10 min, and the melting temperature is 135 DEG C or lower.

The elastomer is a non-crystalline amorphous polypropylene resin containing 5 to 30 mol% of ethylene and 5 to 30 mol% of 1-butene in a propylene component and having a melt index (230 DEG C, 2.16 kg load) of 1 to 10 g / Wherein the composition is a composition.

The mixed resin (c) contains 20 to 30% by weight of the low-density polyethylene and 70 to 80% by weight of the linear low-density polyethylene and has a melt index (190 DEG C, 2.16 kg load) of 10 to 15 g / 0.920 to 0.925 g / cm < 3 >.

The slip agent may also be selected from the group consisting of erucamide, oleamide, behenamide stearamide, stearyl stearamidel, stearyl erucamide, And at least one amide-based slipping agent selected from the group consisting of oleyl palmitate amide.

And the anti-blocking agent is silica or zeolite.

According to the method for producing a polypropylene resin composition of the present invention, the elastomer component to be mixed and extruded into the propylene-ethylene-1-butene random copolymer is used as the same component as the propylene-ethylene-1-butene random copolymer, , It is highly compatible with the two resins to give a high shrinkage ratio, transparency and low temperature heat sealing composition, so that it can be used as a shrink film for large-sized packaging and high-speed packaging which are difficult to apply to existing products It is possible to provide a usable polypropylene resin composition production method.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately The present invention should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention. Accordingly, it is to be understood that the constituent features of the embodiments described herein are merely the most preferred embodiments of the present invention, and are not intended to represent all of the inventive concepts of the present invention, so that various equivalents, And the like.

The present invention relates to (a) 70 to 89% by weight of a crystalline propylene-ethylene-1-butene random copolymer prepared from propylene, ethylene and 1-butene as raw materials and introduced into a mixer in a polymerization reactor; (b) 10 to 25% by weight of an elastomer prepared in the same polymerization reactor as the raw material (a) and introduced into the mixer; (c) 1 to 5% by weight of a mixed resin of low density polyethylene and linear low density polyethylene; (d) 0.01 to 0.5 parts by weight of a slip agent based on 100 parts by weight of the total of the components (a) to (c); And (e) 0.01 to 0.5 parts by weight of an anti-blocking agent per 100 parts by weight of the total of the components (a) to (c) are mixed and extruded in a mixer to produce a polypropylene resin composition. Hereinafter, each component constituting the present invention will be described in detail.

(a) a crystalline propylene-ethylene-1-butene random copolymer

In the present invention, the crystalline propylene-ethylene-1-butene random copolymer is prepared in a polymerization reactor using propylene, ethylene and 1-butene as raw materials, and is introduced into a mixer and mixed with other components to be described later and supplied to the extruder.

The crystalline propylene-ethylene-1-butene random copolymer may contain 1 to 10 mol% of ethylene and 1-butene, respectively, and the remaining 80 to 98 mol% of propylene. The melting temperature by DSC is preferably 135 占 폚 or lower, and the melt index is preferably 3 to 10 g / 10 min (230 占 폚, 2.16 kg).

This propylene-ethylene-1-butene random copolymer can maintain bubble stability, bubble burst, film thickness variation, and the like during biaxial stretching due to inflation while maintaining the transparency of the polypropylene resin composition of the present invention, ≪ / RTI > component with good optical and thermodynamic compatibility.

When the content of ethylene and 1-butene constituting the propylene-ethylene-1-butene random copolymer is less than 1 mol%, the degree of crystallization of the copolymer becomes higher than necessary, thereby increasing the heat sealing temperature of the resultant composition and increasing the softness If it is more than 10 mol%, the crystallinity is rapidly lowered and the adhesion due to low molecular weight is increased, which may cause blocking of the film.

If the melt index of the propylene-ethylene-1-butene random copolymer is less than 3 g / 10 min, the extrusion amount may be lowered, and if it exceeds 10 g / 10 min, the bubble may be shaken. If the melting temperature is higher than 135 ° C, the degree of crystallization of the copolymer becomes higher than necessary, thereby increasing the heat sealing temperature of the resulting composition and improving the softness.

(b) Propylene-ethylene-1-butene elastomer

In the present invention, the elastomer is a propylene-ethylene-1-butene elastomer having the same composition as the crystalline propylene-ethylene-1-butene random copolymer (a) Is prepared in the same polymerization reactor using the same raw materials as the propylene, ethylene and 1-butene used in the preparation of the coalescent, and is introduced into the mixer and mixed with the other components and supplied to the extruder.

That is, in the conventional extrusion process using a crystalline propylene-ethylene-1-butene random copolymer, an elastomer product which is separately prepared with a composition different from that of the crystalline propylene-ethylene-1-butene random copolymer component is mixed with the extruder However, in the present invention, an elastomer is prepared and mixed with the propylene, ethylene, and 1-butene raw materials fed in the same line by using the same reactor and by adjusting the content thereof, reaction conditions, -Butene random copolymer, it is possible to give a high shrinkage ratio, transparency and low-temperature heat sealing composition.

The propylene-ethylene-1-butene elastomer is an amorphous polypropylene resin composition having no crystallinity. The amorphous polypropylene resin composition has a melting temperature of 100 占 폚 or less and a softening point temperature of 80 占 폚 or less. The propylene component has 5 to 30% 30 mol%, and the melt index (230 DEG C, 2.16 kg load) is preferably 1 to 10 g / 10 min.

When the content of ethylene or 1-butene is less than 5 mol%, the softness of the elastomer is deteriorated and the melting temperature is increased. As a result, And can cause sticky blocking due to low molecular weight. If the melt index is less than 1 g / 10 min, the extrusion amount may be lowered. If the melt index exceeds 10 g / 10 min, the bubble may be shaken. If the melting temperature is higher than 100 ° C, the degree of crystallization of the copolymer becomes higher than necessary, thereby increasing the heat sealing temperature of the resulting composition and increasing the softness. Further, even when the softening point temperature exceeds 80 ° C, a problem of increasing the heat sealing temperature and softness may occur.

On the other hand, the propylene-ethylene-1-butene elastomer is preferably produced using a metallocene catalyst, and has a molecular weight distribution narrower than that copolymerized with a Ziegler-Natta catalyst, so that blocking due to adhesion of a low molecular weight polymer is small , Has a low melting temperature, is excellent in the synthesis of a low temperature heat seal, and can have softness with a low surface hardness.

In the present invention, the propylene-ethylene-1-butene elastomer is contained in an amount of 10 to 25% by weight of the resin component of the final composition. When the content of propylene-ethylene-1-butene elastomer is less than 10% by weight, transparency is good, but softness and low-temperature heat-sealability can be deteriorated. When the content is more than 25% by weight, softness is more than necessary and bubble stability, , Biaxial stretching processability such as film thickness variation may be deteriorated.

(c) Mixed resin of low density polyethylene and linear low density polyethylene

In the present invention, the mixed propylene-ethylene-1-butene random copolymer and the propylene-ethylene-1-butene elastomer as the resin component together with the crystalline propylene-ethylene-1-butene random copolymer and the low-density polyethylene and the linear low density polyethylene are used to further improve the bubble stability.

In order to improve the bubble stability, the mixed resin includes 20 to 30% by weight of the low-density polyethylene and 70 to 80% by weight of the linear low-density polyethylene and has a melt index (190 ° C, 2.16 kg load) of 10 to 15 g / It is preferable to use one having a density of 0.920 to 0.925 g / cm3.

(d) Slip agent

In the present invention, the slip agent is added to the film surface to reduce the sticky phenomenon and improve the slip of the surface, and it is preferable to use an amidic slip agent. That is, the amide slip agent can be preferably used as a compound having a high melting point of amide series synthesized from a fatty acid and having a hydroxyl group substituted with an amino structure to have a neutral structure.

Examples of the amide-based slipping agent include, but are not limited to, erucamide, oleamide, behenamide stearamide, stearyl stearamidel,

Stearyl erucamide, oleyl palmityl amide, and the like.

The slip agent preferably has an average particle diameter of 1 to 2 mm, preferably 1.1 to 1.5 mm, and an average particle diameter of 0.1 to 0.9 mm, preferably 0.2 to 0.6 mm.

Such a slip agent is a resin composition comprising 100 parts by weight of a mixed resin of a crystalline propylene-ethylene-1-butene random copolymer, propylene-ethylene-1-butene elastomer, low density polyethylene and linear low density polyethylene By weight based on the total weight of the composition. If the content of the slip agent is less than 0.01 parts by weight, the film may be deteriorated. If the amount of the slip agent is more than 0.5 parts by weight, the slip property may be excessively increased.

(e) Anti-blocking agent

In the present invention, the anti-blocking agent is added to minimize the migration of the soluble fraction because the anti-blocking agent serves to trap the low molecular weight material on the surface of the film, so that silica or zeolite can be used.

Wherein the silica is a conventional silica of the silica, but may be used, porous white amorphous known in the art and is not particularly limited, a particle size of 2 ~ 5.3㎛, the volume of the pores is 0.4 ~ 0.8㎖ / g, SiO ₂ Is preferably 99 mol% or more. It is also preferable to use particles having a water content of less than 2% by weight when dried at 160 캜.

The zeolite is not particularly limited, and conventional zeolites known in the art can be used. For example, monoclinic zeolite can be used. The size of the zeolite particles should be within a range that does not lower the degree of fogging of the film, so that the size of zeolite particles synthesized using sodalite is preferably 2 to 5 μm. Also, the bulk density of the particles is 0.3 to 0.5 g / ml, the average pore interconnected channel is 5 to 15 angstroms, preferably 7 to 12 angstroms, and the specific surface area is 80 to 200 mils / g, a pH of 8 to 9, and a whiteness of 95 or more.

Such an anti-blocking agent is a resin composition comprising 100 parts by weight of a mixed resin of a crystalline propylene-ethylene-1-butene random copolymer, propylene-ethylene-1-butene elastomer, low density polyethylene and linear low density polyethylene 0.01 to 0.5 parts by weight based on 100 parts by weight of the composition. When the content of the anti-blocking agent is less than 0.01 part by weight, the printing property and blocking property of the product using the polypropylene resin composition may be deteriorated. If the content is more than 0.5 part by weight, the transparency of the product may be deteriorated.

In preparing the polypropylene resin composition of the present invention, one or more conventional additives known in the art may be further added as other additives in addition to the above components, for example, an antioxidant, a neutralizing agent, an ultraviolet stabilizer, and an antistatic agent. In this case, each of the additives may be included in the range of 0.01 to 1 part by weight based on 100 parts by weight of the resin composition of the present invention.

The antioxidant is used for preventing the resin molecules from being broken by heat, oxygen, or the like when the film is produced by using the polypropylene resin composition. The neutralizing agent is generated by the residue (metal component) of the catalyst used in the polymerization To neutralize the acid (e.g., HCl) that may be present. Further, the ultraviolet stabilizer is for preventing the molecular chains of the resin from being broken by ultraviolet rays, and the antistatic agent is for reducing the generation of static electricity in a film produced by using the polypropylene resin composition.

In the present invention, the mixing and extrusion of the components may be performed according to a conventional method known in the art. For example, the crystalline propylene-ethylene-1-butene random copolymer and propylene-ethylene-1-butene elastomer prepared in the same polymerization reactor and other components are added to the Henschel mixer in the required amount, and the Henschel mixer is heated at 300 to 700 rpm The mixture was mixed for 0.1 to 2 minutes under the condition of 0.5 to 3 minutes and 1,200 to 1,800 rpm under the condition of 300 to 700 rpm for a total of 2 to 8 minutes. To 230 deg. C, preferably 180 deg. 220 deg. C, and a L / D of 25 or greater, a multi-screw extruder, a kneader or a Benbury mixer. Preferably, the polypropylene resin composition can be prepared using a 40 mm co-axial direction twin-screw extruder having an L / D ratio of 40 and a side feeder under the processing conditions of an extruder having a forming temperature of 160 to 220 ° C and an extruder having a forming speed of 300 to 500 rpm have.

The polypropylene resin composition of the present invention can be molded into a molded article using a known molding method, and can be preferably formed into a film, more preferably a film for low temperature thermal bonding. For example, a film can be prepared from a polypropylene resin composition through a process of stretching a film that has been cooled with water through a circular die at a high temperature of 100 to 150 ° C by using an extruder having a molding temperature of 150 to 220 ° C.

Hereinafter, the present invention will be described in detail with reference to examples.

Example  One

(a) A crystalline propylene-ethylene-1-butene random copolymer (ethylene content: 5 mol%, 1-butene content: 3.5 mol%, melt index Propylene-ethylene-1-butene elastomer (ethylene content: 10 mol%, 1-butene content: 10 mol%, produced by using the polymerization reactor and the same raw materials) 25% by weight of low density polyethylene and 75% by weight of linear low density polyethylene) having a melt index (190 DEG C, 2.16 kg load (weight) (D) 0.5 parts by weight of an amide-based slipping agent in an amount of 100 parts by weight based on 100 parts by weight of the components (a) to (c) 0.5 parts by weight of a porous silica blocking agent was added to a Henschel mixer in an amount of 100 parts by weight based on 100 parts by weight of the total of components c) For 0.5 minutes and then mixed again at 500 rpm to discharge the sample out. The mixture was thoroughly mixed for 3 to 5 minutes, and then the working temperature was adjusted to 180 to 220 ° C using a 40 mm single screw extruder having an L / D of 35 Thereby preparing a polypropylene resin composition. Thereafter, a film was prepared from the polypropylene resin composition through a process of stretching a resin-water-cooled film through a circular die at a high temperature of 100 to 150 ° C by using an extruder having a molding temperature of 150 to 220 ° C.

Example  2

(A) 80% by weight of a crystalline propylene-ethylene-1-butene random copolymer having an ethylene content of 5 mol%, a 1-butene content of 10 mol%, a melt index of 5.5 g / 10 min, Except that 15% by weight of ethylene-1-butene elastomer (melt index: 10 g / 10 min) and 15% by weight of a mixed resin (melt index: 15 g / 10 min) .

Example  3

89% by weight of crystalline propylene-ethylene-1-butene random copolymer (ethylene content 10 mol%, 1-butene content 7.5 mol%, melt index 5.5 g / 10 min), (b) propylene- The same procedure as in Example 1 was carried out except that the component properties and the content were adjusted to 10 wt% of ethylene-1-butene elastomer (melt index 1 g / 10 min) and 1 wt% of a mixed resin (melt index 10 g / 10 min) .

Comparative Example  One

89% by weight of crystalline propylene-ethylene-1-butene random copolymer (ethylene content 10 mol%, 1-butene content 7.5 mol%, melt index 12 g / 10 min), (b) propylene- -1-butene elastomer, and (c) 1% by weight of a mixed resin. The film was prepared in the same manner as in Example 1, except that the component properties and the content were controlled.

Comparative Example  2

(A) 90 wt% of a crystalline propylene-ethylene-1-butene random copolymer (ethylene content 12 mol%, 1-butene content 7.5 mol%, melt index 5 g / 10 min), (b) propylene- -1-butene elastomer, and (c) 5 wt% of a mixed resin were prepared in the same manner as in Example 1, except that the physical properties and the content of the components were controlled.

Comparative Example  3

(A) 85 wt% of crystalline propylene-ethylene-1-butene random copolymer (ethylene content 3 mol%, 1-butene content 7.5 mol%, melt index 1 g / 10 min) and (b) propylene- -1-butene elastomer was prepared in the same manner as in Example 1, except that the component properties and the content were adjusted to 10 wt%.

Comparative Example  4

(A) a crystalline propylene-ethylene-1-butene random copolymer (ethylene content: 3 mol%, 1-butene content: 7.5 mol%, melt index: 5.5 g / 10 min (D) 15 parts by weight of a propylene-ethylene-1-butene elastomer (b), 0.5 part by weight of a slip agent and 0.5 part by weight of an anti-blocking agent. A film was prepared in the same manner as in Example 1.

Comparative Example  5

(A) a crystalline propylene-ethylene-1-butene random copolymer (having an ethylene content of 3 mol% and a 1-butene content of 7.5 mol%), Of the propylene-ethylene-1-butene elastomer, (b) 85% by weight of the propylene-ethylene-1-butene elastomer And the film was prepared in the same manner as in (1).

Comparative Example  6

(A) 68 wt% of crystalline propylene-ethylene-1-butene random copolymer (ethylene content 3 mol%, 1-butene content 7.5 mol%, melt index 5.5 g / 10 min), (b) propylene- A film was prepared in the same manner as in Example 1 except that 27% by weight of ethylene-1-butene elastomer, 0.5% by weight of a slip agent (d) and 0.5% by weight of an antiflocculating agent (e) .

Comparative Example  7

(Propylene content: 70 mol%, melt index (230 DEG C, 2.16 kg): 7 g / 10 min) instead of the propylene-ethylene-1-butene elastomer (b) ) Was put into a mixer, the film was produced in the same manner as in Example 1.

Test Example

The properties of the films prepared according to Examples and Comparative Examples were evaluated according to the following methods, and the results are shown in Table 1 below.

[Assessment Methods]

1) Shrinkage: A film having a size of 10 cm x 10 cm was immersed in oil at 120 DEG C for 10 seconds, and the shrinkage ratio was measured.

2) Haze: An indicator of the transparency of the film was measured by a flow chart of a 20 탆 stretched film based on ASTM D-1003 method.

3) Bubble stability: The number of times the bubble was shaken or ruptured for 3 minutes was measured, and it was measured as "⊚" (very good) in case of 0, "◯" (good) in case of 1 time, "△" And "X" (defective) when it was more than 4 times.

4) Composition: inflation The property required for the film to measure how easy it is to open the closed film part. It is measured as the number of times it is opened when a certain force is applied. If it is "1" (Good) for 2 to 3 times, "△" (normal) for 4 to 5 times, and "X" (poor) for 6 or more times.

5) Slip property: The coefficient of friction (COF) between the films was measured according to the ASTM D1894 method. When the film thickness was less than 0.15, the film was evaluated as "good" (Normal) in the case of less than 0.50 and "X" (poor) in the case of more than 0.50.

6) Thermal Adhesion: When the thermal bonding temperature (TEST condition: 2 kg / 1 second) between the films was measured, "⊚" (very good) (Normal) in the case of less than 125, and "X" (inferior) in the case of 125 or more.

Referring to Table 1, a crystalline propylene-ethylene-1-butene random copolymer and a propylene-ethylene-1-butene random copolymer prepared using the same polymerization reactor and the same propylene, ethylene and 1-butene feedstock in accordance with the present invention It is confirmed that the film prepared by including the optimum content of each component having specific physical properties including excellent transparency, processability and thermal adhesiveness, and significantly improved shrinkage ratio.

On the other hand, when the specific properties and the content of the resin composition according to the present invention exceeded the specific properties and contents (Comparative Examples 1 to 6), one or more of the shrinkage, transparency, workability and heat- -1-butene random copolymer was added separately (Comparative Example 7), the workability was somewhat lowered and shrinkage and transparency were remarkably lowered compared with the Examples.

While the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, Such modifications and changes are to be considered as falling within the scope of the following claims.

Claims (6)

A method for producing a polypropylene resin composition for use as a shrink film by mixing and extruding the following components in a mixer and an extruder, wherein a shrinkage according to the following measuring method of a film made of the polypropylene resin composition is 70% (Haze) of 1.7% or less and a thermal bonding temperature of less than 120 占 폚.
(a) a crystalline propylene-ethylene-1-butene random copolymer prepared from propylene, ethylene and 1-butene as raw materials in a polymerization reactor and fed into a mixer, wherein the propylene component comprises 1 to 10 mol% 70 to 89% by weight of a crystalline propylene-ethylene-1-butene random copolymer containing 1 to 10 mol%, a melt index (230 DEG C, 2.16 kg load) of 3 to 10 g / 10 min and a melting temperature of 135 DEG C or less;
(b) an elastomer produced by the same polymerization reactor as the raw material (a) and charged to the mixer, wherein the propylene component contains 5 to 30 mol% of ethylene and 5 to 30 mol% of 1-butene, 10 to 25 g / 10 min, a melting temperature of 100 占 폚 or less, and a softening point temperature of 80 占 폚 or less); and 10 to 25% by weight of a crystalline amorphous polypropylene resin composition;
(c) 1 to 5% by weight of a mixed resin of low density polyethylene and linear low density polyethylene;
(d) 0.01 to 0.5 parts by weight of a slip agent based on 100 parts by weight of the total of the components (a) to (c); And
(e) 0.01 to 0.5 parts by weight of an anti-blocking agent per 100 parts by weight of the components (a) to (c).
[How to measure]
The shrinkage was measured by immersing a film having a size of 10 cm x 10 cm in oil at 120 deg. C for 10 seconds and measuring Haze according to ASTM D-1003 method using a flow chart of a 20 mu m stretched film. / 1 second Measures the thermal bonding temperature. delete delete The method according to claim 1,
The mixed resin (c) contains 20 to 30% by weight of the low density polyethylene and 70 to 80% by weight of the linear low density polyethylene, and has a melt index (190 캜, 2.16 kg load) of 10 to 15 g / 10 min and a density of 0.920 To 0.925 g / cm < 3 >. The method according to claim 1,
The slip agent may be selected from the group consisting of erucamide, oleamide, behenamide stearamide, stearyl stearamidel, stearyl erucamide, And at least one amide-based slipping agent selected from the group consisting of oleyl palmitate amide. The method according to claim 1,
Wherein the anti-blocking agent is silica or zeolite.