KR101933907B1 - Cpp film and package comprising cpp film - Google Patents

Abstract

The present invention relates to a cast polypropylene (CPP) film and, more specifically, to a resin composition for forming a CPP film which exhibits excellent sealing properties at a relatively low temperature when a food packaging material is thermally bonded and can be sealed and packed at high speed, to the CPP film produced from the resin composition, particularly, the CPP film which has excellent thermal adhesion at a low temperature and barrier properties, and to a food packaging material including the same. According to the present invention, the CPP film can exhibit excellent thermal adhesion implemented at high speed even at a very low temperature as compared with a conventional CPP film, thereby reducing production costs, since a deviation of the thermal adhesion strength is low, it is possible to set a temperature of thermal adhesion of a packaging line over a wide range, thereby ensuring convenience of operation, and thus, it is possible to reduce the defective rate of packaging even when temperature deviation occurs. In addition, a packaging material which is produced from the CPP film shows excellent flexibility, thereby improving quality of packaging, and exhibits excellent heat adhesion at a folded portion at the center or an edge when being thermally bonded, and thus, it is possible to prevent not only foreign matters, microorganism, and insects but also air from entering. Moreover, it is possible to further prevent oxygen and moisture from penetrating into the packaging material, and thus, it is possible to store food contained in the packaging material for a relatively long period, and the film is thermally bonded at a low temperature, and thus, it is possible to prevent shrinkage of the packaging material that occurs when heat is applied to a surface of the packaging material as compared to a conventional case, thereby being capable of performing excellent quality of packaging. Therefore, it is possible to perform packaging of relatively uniform quality, thereby reducing time and costs consumed for a thermal adhesion process, and thus, it is possible to enhance the quality of packaging and productivity while reducing production costs.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an unleaded polypropylene film and a food packaging material containing the same.

The present invention relates to an unleaded polypropylene film and a food packaging material containing the same. More particularly, the present invention relates to an unleaded polypropylene film which is excellent in sealing property at a low temperature when a food packaging material is thermally adhered, A resin composition for forming a cast polypropylene film (CPP film), a CPP film formed from the resin composition, particularly a CPP film excellent in low temperature thermal adhesion and barrier properties, and a packaging material comprising the film.

Conventionally, the food packaging material has been made of a CPP film composed of a skin layer, a core layer and a sealing layer, or a PET or OPP (oriented polypropylene) film laminated on the CPP film. Such a conventional unleaded polypropylene film has lower gloss and transparency than an oriented polypropylene (OPP) film, but is inexpensive and is widely used in packaging materials requiring low temperature impact strength and heat adhesion.

At this time, the sealing layer is located on the innermost surface of the packaging material, storing the contents, facing the sealing layers facing each other, and sealing the packaging material by applying heat and pressure to the portions. When the sealing layer is pressed by a seal bar heated to a predetermined temperature after facing the other sealing layers, the resin of the sealing layers facing each other melts and is fused and sealed.

Since the thermal bonding process of the sealing layer is a major factor involved in productivity, it is necessary to reduce the time required for thermal bonding by increasing the packing speed. Therefore, it may be considered to bond at a high temperature to reduce the heat bonding time, or to lower the heat bonding temperature of the resin used for the sealing layer. However, since sealing between the sealing layers at a high temperature can seal the entire film by heat, it is more preferable to use a resin having a low thermal bonding temperature for the sealing layer.

As a conventional sealing layer, a resin composition containing a terpolymer of propylene-butene-ethylene and an anti-blocking agent (ABA) has been mainly used. However, such a composition has a Vicat softening point 115 占 폚, and it is necessary to set a heat bonding temperature of about 140 to 145 占 폚 in a sealing operation. However, there is a problem that the quality of the packaging material does not reach a satisfactory level due to a high heat bonding temperature, the productivity can not be increased, and the cost for raising the temperature to a high heat bonding temperature is large.

Korean Patent No. 10-1375917 (Apr. 13, 2014)

The inventors of the present invention have conducted intensive studies to overcome the problems of the prior art accompanied with the packaging film and to provide a packaging film having good sealability at a low temperature and excellent heat bonding strength. As a result, it has been found that a CPP packaging film The present invention has been accomplished based on the discovery that it is possible to satisfy such requirements and to provide high productivity such as high-speed packaging due to excellent oxygen and moisture barrier properties.

Accordingly, an object of the present invention is to provide a resin composition for forming a lead-free polypropylene film which is excellent in sealing property at a low temperature, excellent in thermal bonding strength, excellent in oxygen and moisture barrier properties and can be sealed at high speed, CPP film, and a packaging material comprising the film.

SUMMARY OF THE INVENTION The object of the present invention is, in one aspect,

An outer layer (10) comprising 5 to 30% by weight of an antiblocking agent and 70 to 95% by weight of a cycloolefin copolymer copolymerized with ethylene and norbornene;

An intermediate layer 20 made of homopolypropylene;

A resin composition comprising 3 to 10 wt% of an antiblocking agent, 3 to 10 wt% of a polyolefin elastomer, 75 to 90 wt% of an elastomer of a propylene-ethylene copolymer, and 3 to 10 wt% of an elastomer of a propylene-butene- An inner layer 30,

And a heat bonding temperature of 100 to 110 ° C.

In another aspect, the object of the present invention is to provide an unleaded polypropylene film; And an outermost layer 40 made of an aluminum (Al) vapor deposition layer.

An object of the present invention is, in still another further aspect, the above-mentioned unleaded polypropylene film; And a packaging material for food packaging characterized in that a PET (polyethylene terephthalate) film or an oriented polypropylene (OPP) film is laminated on the outermost layer of the non-oriented polypropylene film.

The CPP film according to the present invention can provide excellent thermal adhesiveness at a high speed even at a significantly low temperature as compared with the conventional CPP film and can reduce the production cost, It is easy to set the thermal bonding temperature, thereby ensuring the convenience of the operation, thereby reducing the defective packaging rate even if a temperature deviation occurs. In addition, the packaging material made of the CPP film has excellent flexibility and can improve the packaging quality, and can be thermally adhered at the center folding portion or the edge portion at the time of high-speed thermal bonding, Can be prevented. Further, the permeation of oxygen and moisture into the packaging material can be further suppressed, the storage of the food in the packaging material can be made longer, and the thermal bonding is performed at a low temperature. As a result, contraction of the packaging material due to heat It is possible to realize an excellent packaging quality. Therefore, packaging with comparatively uniform quality can be realized, and cost and time required for the thermal bonding process can be reduced, thereby improving packaging quality, improving productivity, and reducing production costs.

1 is a cross-sectional view showing the layer structure of a CPP film according to the present invention.
FIG. 2 is a view schematically showing the outside of a packaging material when the contents are packaged using the packaging material containing the CPP film of the present invention, and shows the center folded portion or the edge portion.
Fig. 3 is a process explanatory view showing a manufacturing process of the CPP film of the present invention.
Fig. 4 is a graph comparing weight increase amounts due to moisture penetration. Fig.

The present invention, in one aspect,

An outer layer (10) comprising 5 to 30% by weight of an antiblocking agent and 70 to 95% by weight of a cycloolefin copolymer copolymerized with ethylene and norbornene;

An intermediate layer 20 made of homopolypropylene;

A resin composition comprising 3 to 10 wt% of an antiblocking agent, 3 to 10 wt% of a polyolefin elastomer, 75 to 90 wt% of an elastomer of a propylene-ethylene copolymer, and 3 to 10 wt% of an elastomer of a propylene-butene- An inner layer 30,

And a heat bonding temperature of 100 to 110 占 폚.

In another aspect of the present invention, the cycloolefin copolymer has a norbornene content of 20-95 wt%.

In another embodiment of the present invention, the non-oriented polypropylene film has a thickness of 15 to 50 μm, and the thickness of the outer layer, the intermediate layer and the inner layer is 10-30: 30-80: 10-40 The present invention provides a polypropylene film which is free of lead.

In a further another aspect of the present invention, the non-oriented polypropylene film; And an outermost layer 40 made of an Al vapor deposition layer.

In a further another aspect of the present invention, the non-oriented polypropylene film; And a PET film or an oriented polypropylene (OPP) film laminated on the outermost layer of the non-extensible polypropylene film processed with AL deposition.

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Hereinafter, the non-oriented polypropylene film and the packaging material containing the same according to the present invention will be described in more detail with reference to the accompanying drawings.

It is to be understood that the words or words used in the present specification and claims are not to be construed in a conventional or dictionary sense and that the inventor can properly define the concept of a term in order to describe its invention in the best possible way And should be construed in light of the meanings and concepts consistent with the technical idea of the present invention. Therefore, it should be understood that the embodiments described herein and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and that various equivalents and modifications may be substituted for them at the time of the present application shall.

The present invention has a technical feature to provide an effect of enhancing the productivity of a unit packaged product by providing a wrapping paper excellent in thermal adhesiveness even at a temperature of 110 DEG C or less while maintaining excellent moisture and oxygen barrier properties. The conventional packaging film is subjected to a sealing process at a relatively high temperature of 140 to 145 ° C and the packaging productivity after storage of the contents due to such a high thermal bonding temperature is lowered. And can provide various advantages.

FIG. 1 is a cross-sectional view illustrating a layer structure of a CPP film according to the present invention. FIG. 2 is a view schematically showing the exterior of a packaging material when the contents are packed using the CPP film of the present invention. Fig. 3 is a process explanatory view showing a manufacturing process of the CPP film of the present invention. Fig.

The CPP film according to the present invention mainly comprises an outer layer 10, an intermediate layer 20 and an inner layer 30.

The outer layer 10 is required to have excellent anti-blocking properties corresponding to the outer surface of the CPP film according to the present invention and to maintain a constant rigidity. Further, it is more preferable that the outer layer 10 has an excellent bonding strength with aluminum which is vacuum-deposited if necessary.

Preferably, the outer layer 10 comprises 5 to 30% by weight of an anti-blocking agent and 70 to 95% by weight of a cycloolefin copolymer in which ethylene and norbornene are copolymerized.

The anti-blocking agent may be added to prevent deterioration in workability due to blocking between the thermally adhesive films, and it is preferably added in an amount of 30 wt% or less. When such an antiblocking agent is used in an amount exceeding 30% by weight, the haze value is increased to lower transparency, which is not preferable.

The antiblocking agent can be suitably applied to the present invention as long as it is conventionally used. For example, though not limited to these, there may be mentioned a plastic comb Jong Il's AB1305PM3, calcium carbonate CaCO _3), talc (Talc), silica (SiO _2), aluminum silicate, and silicone bead, etc. These antiblocking agents may be used singly or in combination of two or more.

The cycloolefin copolymer in which ethylene and norbornene are copolymerized is added in order to prevent gas and water vapor from flowing into the packaging material for long-term preservation of the food. The cycloolefin copolymer is a cycloolefin copolymer represented by the following formula (1) Olefin-Copolymer (COC) resin can be preferably used.

The cycloolefin copolymer represented by the above formula (1) is an ethylene-norbornene copolymer in which ethylene and norbornene are copolymerized, and is an amorphous thermoplastic resin.

It is more preferable that the content of the norbornene contained in the copolymer is in the range of 20 to 95% by weight. When the content of the norbornene is 20 wt% or less, it is not preferable because it does not greatly affect the oxygen and water permeation barrier properties.

The intermediate layer 20 serves as a base material of the film, and has a tensile and elongation ratio, affects the stiffness of the film, has a large amount of addition in the layer ratio of the film so as to improve gas barrier properties, Is particularly preferable.

When the inner layer 30 is pressed by a seal bar, the resin is melted by heat to cause fusion between the resins, and therefore, the inner layer 30 should be particularly excellent in low temperature thermal adhesiveness.

The components satisfying these requirements include 3 to 10 wt% of an antiblocking agent, 3 to 10 wt% of a polyolefin elastomer, 75 to 90 wt% of an elastomer of a propylene-ethylene copolymer and 3 to 10 wt% of an elastomer of a propylene-butene- May be preferably used.

The anti-blocking agent is added to prevent blocking and provide slippery property. It prevents blocking of the inner layer and outer layer when the packaging material is rolled up during storage and transportation during winding and use, and furthermore, Facing the opening in order to seal the contents in the package after sealing in a confronting state.

If the content of the antiblocking agent is less than 3% by weight, the antiblocking property and the slipping property are insufficient, and the opening of the packaging material for sealing the food into the packaging material is not easy, which may reduce the workability. On the other hand, when the content of the antiblocking agent is more than 10% by weight, the thermal bonding temperature on the inner layer of the film becomes high, which may interfere with the low-temperature thermal bonding and lower the transparency of the film and the glossiness after deposition

The constituent components of the inner layer 30 may include a polyolefin elastomer and a propylene-ethylene copolymer together with propylene-butene-ethylene terpolymer resin in an appropriate ratio to lower the Vicat softening point at the time of sealing. Therefore, the sealing rate can be increased by using the composition of the inner layer, and the productivity of the packaging can be remarkably improved.

The olefin block copolymer (GARDE name: INFUSE 9507, MI 5.0, density 0.866 g / cm 3) may be used as the olefin block copolymer to increase the adhesion performance during the sealing process.

The elastomer of the propylene-ethylene copolymer is a resin having a Vicat softening point of 60 DEG C, and has a Vicat softening point lower by about 55 DEG C than a propylene-butene-ethylene terpolymer.

The polyolefin elastomer is preferably contained in an amount of 3 to 10% by weight based on the total amount of the composition of the inner layer, and if it is 10% by weight or more, the hardness becomes strong, which may deteriorate the packaging characteristics.

The content of the elastomer of the propylene-ethylene copolymer is preferably 75 to 90% by weight, and it is difficult to lower the Vicat softening point at 75% by weight or less, and there is a problem of blocking at 90% by weight or more.

It is preferable that the propylene-butene-ethylene terpolymer is contained in an amount of 10 wt% or less. If the propylene-butene-ethylene terpolymer content is more than 10 wt%, the elastomer content of the propylene- As a result, the effect of improving the productivity by heat bonding can not be sufficiently obtained by lowering the heat bonding temperature.

The thickness of the non-oriented polypropylene film is preferably 15 to 50 μm, and the thickness of the outer layer, the intermediate layer and the inner layer is preferably 10-30: 30-80: 10-40.

On the other hand, the thickness of the CPP film for packaging material obtained in the present invention is not limited to this, but it is preferable that the thickness is 15 탆 or more. Films having a thickness of less than 15 占 퐉 cause cost increase in the production thereof and are not economically easy to produce. On the other hand, the upper limit of the thickness of the CPP film is not particularly limited, and there is no particular limitation to the application of the inner layer of the present invention. However, when the thickness of the film has a thickness exceeding 50 탆, it may not be suitable for high-speed packaging in sealing by using it. The CPP film having a thickness of 20 to 30 占 퐉 may be more preferable from the viewpoints of ease of manufacture and high-speed packaging.

At this time, the thickness of each of the outer layer 10, the intermediate layer 20, and the inner layer 30 is preferably 10 to 30, 30 to 80, and 10 to 40 in the entire thickness of the film.

In the case of the outer layer 10, if it is too thin, there arises a problem of AL deposition bonding strength or poor heat resistance. In addition, when the thickness exceeds the set range, there is a disadvantage in that the film is too thick and the film has poor stiffness and processability.

When the thickness of the intermediate layer 20 is less than 30, the final packaging paper can not be easily waterproofed and the packaging paper may have a low value. If the thickness ratio exceeds 80, There is a disadvantage that adhesion with other layers is not easy. When the inner layer 30 is 10 or less, the adhesion is low and the adhesion is not easy.

Meanwhile, the CPP film of the present invention may further include an aluminum deposition layer on the surface of the outer layer to provide a food packaging material.

When a certain metal is heated to a melting point or higher in a high vacuum state, the metal is vaporized and dispersed straight for several tens of centimeters without colliding with oxygen and nitrogen molecules, and then condensed in a molecular state to form a thin metal film .

Such a food packaging material is the unleaded polypropylene film; And an outermost layer 40 made of an Al deposition layer; And the like.

The Al deposition layer is excellent in oxygen and water vapor barrier properties and thus provides a function as a barrier layer. The deposition layer may generally be deposited to a thickness of about 380 ANGSTROM. At this time, the optical density (0D) preferably has a value of 2.2 to 2.3.

The A1 deposition layer 40 has a higher bonding force with the A1 deposition layer due to the molecular structure of the cycloolefin copolymer of the outer layer 10. [ Due to the structure of the cycloolefin copolymer, the norbornene branches of the cycloolefin copolymer are more likely to form a deposition layer due to the generation of a polar group, so that the binding force with the A1 deposition layer can be further improved.

The A1 deposition layer is deposited after the corona treatment is performed on the CPP film. At this time, the A1 deposition layer can be more easily formed by introducing the polar group by the surface oxidation by the corona treatment.

On the other hand, the packaging packaging material according to a further embodiment of the present invention comprises the above-mentioned unleaded polypropylene film; And a PET film or an oriented polypropylene (OPP) film laminated on the outermost layer of the non-oriented polypropylene film.

It will be apparent to those skilled in the art to which the present invention pertains that it may have a different layer structure to give additional functionality required depending on the contents to be packaged.

The CPP film according to the present invention can be obtained by laminating a primary product such as a PET film, an OPP film or a BOPP film on the outer layer 10. At this time, the primary product on the outer layer may be laminated with an adhesive.

The above-mentioned packaging film may be subjected to corona treatment if necessary before the step of laminating the CPP film or the deposition of the A1 deposition layer by the adhesive on the outer layer. The corona treatment provides a function of physically modifying the surface of the packaging film of the present invention made of non-polar polypropylene or polyethylene and imparting polarity to improve the adhesive force. As a result, when the packaging film of the present invention is subjected to post-processing, it is possible to obtain an effect of improving the adhesive force of the adhesive, improving the ink adhesion, and improving the adhesive strength when aluminum is deposited.

Hereinafter, a method for producing the CPP film according to the present invention will be described in detail.

The CPP film according to the present invention may be preferably manufactured by an extrusion lamination (= T-die) method.

3, the raw material composition as described above is put into each silo 1 and extruded by the extruder 2. At this time, the unfused resin does not pass through the filter, Extruded through the extruder 2 with the T-die 4 to form a CPP film having a three-layer structure of an outer layer / an intermediate layer / an inner layer.

Subsequently, the molten resin extruded by the T-die is rapidly cooled to 35 DEG C to form crystals and then cast (5) into a film.

After the thickness of the film formed to the target thickness is measured and uniformly adjusted through the B-ray 6, the surface of the obtained film is treated with the corona processor 7, and the foreign substance present on the film surface is detected by the detector 8 ), And the obtained film is wound up with a winder 9 to produce a film.

As described above, the CPP film of the present invention is excellent in productivity because the heat bonding temperature can be remarkably lowered while maintaining excellent moisture and oxygen barrier properties obtained in conventional packaging materials.

Example

Hereinafter, the present invention will be described in more detail with reference to examples. However, these embodiments are intended to illustrate the present invention by way of specific examples, and are not intended to limit the present invention.

Examples 1 to 5: Preparation of CPP film

The following composition and content of raw materials were prepared to prepare a CPP film.

Outer layer: 95% by weight of COC (TOPAS product of Polyplastics Co.) and 5% by weight of AB (AB1305PM3 of Chungil Prakom).

Intermediate layer: 100% by weight of homopolypropylene (HF429 of Hanwha Total).

Inner layer: 83 wt% of an elastomer of a propylene-ethylene copolymer (Vistamaxx 3020FL from Exxon Mobil), 5 wt% of a polyolefin elastomer (Infuse DOW Chemicals), 9 wt% of a propylene-butene-ethylene terpolymer (TF400 of Hanwha TOTAL) 3% by weight of antiblocking agent (AB1305PM3 from Chungil Pracom).

The raw material composition as described above was placed in each silo (1) and extruded into an extruder (2) as shown in the production process of the CPP film shown in Fig. At this time, the CPP film having the three-layer structure of outer layer / intermediate layer / inner layer was formed by co-extruding through the extruder 2 with the T-die 4 while filtering the melted resin without passing through the filter. At this time, the thickness of each layer was adjusted in a ratio as shown in Table 1.

The melted resin extruded by the T-die was rapidly cooled to 35 占 폚 to form crystals and then cast (5) into a film.

The thickness of the film formed through the B-ray 6 was measured and uniformly adjusted to 20 탆.

After the surface of the obtained film was treated with a corona processor 7, the foreign substances present on the surface of the film were detected and removed through a detector 8, and the obtained film was wound with a winder 9.

Oxygen transmission rate (OTR), water permeation rate (WTR or WVTR: water vapor transmission rate), heat bonding temperature and heat bonding strength were measured on the thus obtained film, and the results are shown in Table 1. Each physical property measurement was carried out in the following manner.

-O.D (optical density): Measured by light transmission method with an X-rite O.D measuring instrument.

-OTR and WVTR: Mocon's OX-TRAN model 2/21 and PERMATRAN-W model 3/33 were used. A 50 cm 2 area of the film was placed on the cell and oxygen (23 ° C), moisture C, 100% RH). At this time, nitrogen was used as a carrier gas.

Comparative Example 1

As the outer layer composition, a film was formed in the same manner as in Example 1, except that instead of COC, an outer layer was formed using a composition consisting of 87% by weight of random polypropylene, 10% by weight of EMMA and 3% by weight of an antiblocking agent.

As can be seen from the above test results, the film of the present invention was superior in overall oxygen permeability (OTR) and water permeability as compared with the comparative example, and had a low heat bonding temperature and excellent heat bonding strength.

Examples 6 to 11: Preparation of CPP film

A CPP film was prepared in the same manner as in Example 1, except that the inner layer was prepared in the composition shown in Table 2 below. At this time, the thickness ratio of the outer layer, the middle layer, and the inner layer was 15:65:20. On the other hand, the polyolefin elastomer used for constituting the inner layer was INFUSE 9507, the propylene-ethylene copolymer was Vistamax 3020 from Exxon Mobil, the propylene-butene-ethylene terpolymer was SFC 751M from Lotte Chemical Co., AB1305PM3 was used.

The heat bonding temperature and the heat bonding strength of the CPP film thus obtained were measured, and the results are shown in Table 2 below. The CPP film obtained by the above Comparative Example 1 is also shown in Table 2 for comparison.

Example 6 7 8 9 10 11 Comparative Example 2 Inner layer Infuse9507 10 8 7 5 4 3 - Vistamax3020 75 80 82 85 87 90 95 SFC751M 10 7 6 5 4 3 - AB1305PM3 5 5 5 5 5 4 5 Heat bonding temperature (캜) 103 106 108 110 115 120 141 Thermal Adhesion Strength (g / 15mm) 625 630 630 635 640 660 620

As can be seen from the test results, the film of the present invention had a lower heat bonding temperature and a higher heat bonding strength than that of the comparative example.

Examples 12 to 16 and Comparative Example: Manufacture of a packaging material containing an Al vapor deposition layer

Aluminum was vapor-deposited on the outer layers of each of the films obtained in Examples 1 to 5 and Comparative Example 1 in the form of a vacuum in a Boat type to form an Al deposition layer having a thickness of 380 ANGSTROM.

The optical density, the oxygen permeability and the moisture permeability were measured for each of the films formed with the A1 deposition layer, and the results are shown in Table 3 below.

Example Comparative Example 3 12 13 14 15 16 O.D. 2.2 2.2 2.2 2.2 2.2 2.2 OTR (cc / m < 2 > day) 25 20 12 10 7 60 WVTR (g / m2day) 0.80 0.75 0.63 0.50 0.45 1.2

As can be seen from the results of Table 3 above, the indicator paper of the present invention exhibits superior physical properties in terms of oxygen permeability and moisture permeability as compared with the comparative example.

Examples 17 to 21 and Comparative Example: Production of Food Packaging Materials

The deposited films of Examples 12 to 16 were laminated with a BOPP 20 탆 film to measure OTR and water permeability, and the results are shown in Table 4 below.

At this time, the packaging material formed a food packaging material such as custard nest. The film used for constructing the packaging material was a BOPP 20 μm as a printing fabric, and the above-mentioned inventive film deposited with aluminum was bonded and used with an adhesive. [Condition: BOPP 20 μm + printing + adhesive + aluminum deposition CPP 20 μm, OPTICAL DENSITY: 2.2 (380 A)].

Example Comparative Example 4 17 18 19 20 21 Outer layer (%) 15 20 25 30 35 15 OTR (cc / m < 2 > day) 8.52 7.05 5.30 5.12 3.57 30.90 WVTR (g / m2day) 0.17 0.15 0.12 0.10 0.07 0.55

As can be seen from the results of Table 4, it can be seen that the packaging material of the present invention exhibits excellent barrier properties such that the oxygen permeability (OTR) and water permeability (WVRT) are lower than those of the comparative example.

Test Example 1: Water content change test

The moisture content change of the finished article to which the packaging material product of Example 17 was applied was tested in comparison with the product of Comparative Example 4. [ The packaging material containing the contents was placed in a thermo-hygrostat set at high temperature and high humidity using a thermo-hygrostat (Hanyang Science Grade: TH500). The test conditions were a temperature (50 ° C), a relative humidity (90%), an elapsed time (120 hr) and a quantity of packaging material (12EA each). Fig. 4 is a graph comparing weight increase amounts due to moisture penetration. Fig. As a result, the water increase rate was 0.3979% and the water increase rate was 0.0170%.

As described above, it was confirmed that the water content penetrated into the packaging material of the product of the present invention (Example 17) was remarkably decreased, and the shelf life of the food was longer than that of the conventional (Comparative Example 4).

It can be confirmed that the non-oriented CPP film of the present invention can remarkably lower the heat bonding temperature of the wrapping paper and has excellent physical properties. Particularly, it is possible to perform thermal bonding at a temperature of 110 ° C or lower, thereby lowering the temperature of the seal bar during packaging, thereby reducing the cost and time required for the heat bonding process. In addition, since heat bonding can be performed at a low temperature, shrinkage of the packaging material due to heat applied to the packaging surface can be prevented as compared with the conventional products, thereby achieving excellent packaging quality.

Further, in the case of performing heat bonding at the same temperature as in the prior art, in order to obtain the same heat bonding strength, it is possible to press the package for a shorter time than the conventional one, and the packaging productivity can be improved. Furthermore, the adhesive strength is constant over a wide range of thermal bonding temperatures, so that there is no need to strictly control the thermal bonding temperature in order to achieve the required adhesive strength, and packaging with comparatively uniform quality can be realized even with temperature changes .

In addition, the CPP film according to the present invention is excellent in flexibility and low-temperature thermal adhesiveness, and can be thermally adhered to the center folded portion or the edge portion as shown in FIG. 2, thereby preventing air inflow.

As described above, the packaging material containing the CPP of the present invention can achieve significantly better sealing properties at low temperature than conventional ones, and can obtain excellent effects of improving packaging quality, improving productivity, and reducing production cost.

Furthermore, the packaging material containing the CPP of the present invention can remarkably lower the moisture permeability and the oxygen permeability as compared with the conventional packaging material, and can exert an excellent effect for maintaining the intrinsic quality of the food content during the shelf life. Thus, the present invention is an innovative film of advanced technology that can be used in place of expensive film such as PVDC coating film, EVOH co-extruded film and Alumina transparent deposition film.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation.

10: outer layer
20: middle layer
30: inner layer
40:

Claims (5)

An outer layer (10) comprising 5 to 30% by weight of an antiblocking agent and 70 to 95% by weight of a cycloolefin copolymer copolymerized with ethylene and norbornene;
An intermediate layer 20 made of homopolypropylene;
A resin composition comprising 3 to 10 wt% of an antiblocking agent, 3 to 10 wt% of a polyolefin elastomer, 75 to 90 wt% of an elastomer of a propylene-ethylene copolymer, and 3 to 10 wt% of an elastomer of a propylene-butene- An inner layer 30,
The cycloolefin copolymer has a norbornene content of 20-95 wt%, a thickness of 15-50 μm, a thickness of 10-30: 30-80: 10-40 , A non-oriented polypropylene film having a heat bonding temperature of 100 to 110 캜; And
An Al (aluminum) deposition layer; PET (polyethylene terephthalate) film; Or a stretched polypropylene film laminated on the outermost layer,
The Al deposition layer is deposited to a thickness of 380 ANGSTROM, the optical density (OD) is 2.2 to 2.3,
Wherein the Al deposition layer is deposited after the corona treatment is performed on the non-oriented polypropylene film. delete delete delete delete

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