Packaging material formed of single material, having excellent easy-cut properties and barrier properties, and method for manufacturing same

Abstract

The present invention relates to a packaging material and a method for manufacturing same, the packaging material being laminated with an outer layer, an adhesive layer, a middle layer, and an inner layer, wherein the outer layer is formed by laminating, at an angle of 0° to 30°, a plurality of film layers obtained by cutting, at an angle of 0° to 30° to form a spiral shape, a film formed by blown extrusion using a high-density polyethylene (HDPE) resin, the adhesive layer is formed between the laminated film layers, the middle layer is formed on the outer layer and includes an ethylene vinyl alcohol (EVOH) resin, and the inner layer is formed on the middle layer and includes a linear low-density polyethylene (LLDPE) resin.

Description

Packaging material with excellent single-material easy-cut properties and barrier properties and its manufacturing method

[0001] The present invention relates to a packaging material having excellent easy-cut characteristics and barrier characteristics made of a single material and a method for manufacturing the same, and more specifically, to a packaging material for packaging heavy-weight pet food having excellent easy-cut characteristics and barrier characteristics made of a single material and a method for manufacturing the same.

[0002] With the recent revision of the Resource Recycling Act, demand for recyclable packaging materials has been rapidly increasing. To be considered recyclable, packaging materials must receive an "Excellent" recyclability rating. To achieve this, single-material packaging materials are being developed.

[0003] To address this issue, cross-laminated films with superior properties were developed, complementing the properties of polyethylene (PE). However, these cross-laminated films, with their superior properties in both the machine direction (MD) and transverse direction (TD), presented challenges with easy-cutting. Recently, various packaging materials have been implementing unidirectional easy-cutting capabilities for consumer convenience.

[0004] To solve this problem, the present invention aims to provide a packaging material and a manufacturing method thereof having excellent physical properties in the TD direction and excellent easy cut characteristics in the MD direction by controlling the lamination angle and blown stretching ratio of a cross-lamination film.

[0005] The present invention aims to provide a packaging material that is recyclable using a single material, has excellent physical properties, and has excellent easy-cut characteristics, and a method for manufacturing the same, in order to solve the above-mentioned shortcomings of the prior art.

[0006] The present invention comprises an outer layer in which a plurality of film layers, each of which is cut at an angle of 0° to 30° to form a spiral shape using a blown extruded film made of high-density polyethylene (HDPE) resin, are laminated at an angle of 0° to 30°;

[0007] An adhesive layer formed between the above laminated film layers;

[0008] A middle layer formed on the outer layer and containing ethylene vinyl alcohol (EVOH) resin; and

[0009] A packaging material is provided in which an inner layer including a linear low-density polyethylene (LLDPE) resin is laminated on the above-mentioned middle layer.

[0010]

[0011] In addition, the present invention provides a method for manufacturing a packaging material, including the steps of: manufacturing a cut film by cutting a blown extruded film using a high-density polyethylene (HDPE) resin into a spiral shape at an angle of 0° to 30°; extrusion-coating an adhesive resin on the cut film, and then laminating and bonding another piece of the cut film so that the directional grains of the films intersect at an angle of 0° to 30° to form an outer layer; sequentially laminating an adhesive LDPE layer, a tie resin layer, an ethylene vinyl alcohol (EVOH) resin layer, a tie resin layer, and an adhesive LDPE layer on the outer layer to form a middle layer; and forming an inner layer including a linear low-density polyethylene (LLDPE) resin on the middle layer.

[0012] According to the present invention, a film cut obliquely and having excellent properties in the TD direction and excellent easy-cut characteristics in the MD direction and a polyethylene single-material film can be applied to a composite barrier film manufacturing facility to provide a packaging material used for packaging heavy feed or food with excellent mechanical properties such as tensile strength and tear strength and gas barrier properties.

[0013] The packaging material provided in the present invention is made of a single polyethylene material and is recyclable.

[0014] The present invention can provide a method for manufacturing a packaging material composed of a single polyethylene material with secured productivity through in-line production and having excellent easy-cut characteristics and barrier characteristics.

[0015] Figure 1 is a schematic diagram of a packaging material according to one embodiment of the present invention.

[0016] Figure 2 is a schematic diagram of a packaging material manufacturing device according to one embodiment of the present invention.

[0017] Figure 3 is a MD direction cut photograph and a TD direction cut photograph of a packaging material according to Example 2 of the present invention, in which a cut is made cleanly and easily in the MD direction, and the film is stretched and torn in the TD direction.

[0018] Hereinafter, the present invention will be described in detail.

[0019] A packaging material according to one embodiment of the present invention comprises an outer layer formed by cutting a plurality of film layers, each of which is a blown extruded film using a high-density polyethylene (HDPE) resin, at an angle of 0° to 30° to form a spiral shape, and laminated at an angle of 0° to 30°; an adhesive layer formed between the laminated film layers; a middle layer formed on the outer layer and containing ethylene vinyl alcohol (EVOH) resin; and an inner layer formed on the middle layer and containing linear low-density polyethylene (LLDPE) resin.

[0020] Figure 1 illustrates a packaging material (10) according to one embodiment of the present invention.

[0021] The present invention provides a packaging material comprising an outer layer (20) formed by forming an adhesive layer (23) between a plurality of films (21, 22) cut at an angle of 0° to 30° and laminating them; a middle layer (30) formed on the outer layer and containing ethylene vinyl alcohol (EVOH) resin; and an inner layer (40) formed on the middle layer and containing linear low-density polyethylene (LLDPE) resin.

[0022] The plurality of films (21, 22) cut at an angle of 0° to 30° may be films cut at an angle of 0° to 30° to form a spiral shape using a blown extrusion method using high-density polyethylene (HDPE) resin. Preferably, the films may be cut at an angle of 1° to 30°.

[0023] The above outer layer (20) may be formed by laminating a plurality of films (21, 22) cut at an angle of 0° to 30°, not orthogonally, but at an angle of 0° to 30°. By laminating a plurality of films (21, 22) cut at an angle of 0° to 30°, not orthogonally, but at an angle of 0° to 30°, the physical properties in the TD direction can be strengthened and the easy-cut characteristics (tear characteristics) in the MD direction can be strengthened. If the lamination angle exceeds the above range, the tear strength (tear strength) in the MD direction may be high, making easy-cutting difficult. Preferably, the lamination angle may be 1° to 30°.

[0024] The film manufactured by the above blown extrusion method may have a draw ratio (MD draw ratio / TD draw ratio) within the range of 5:5 to 8:6. When the draw ratio (MD draw ratio / TD draw ratio) is within the range of 5:5 to 8:6, the film may exhibit easy-cut characteristics in the MD direction and enhanced properties in the TD direction. When the draw ratio exceeds the above range, the film may exhibit easy-cut characteristics in both directions and low impact strength.

[0025] The above blown extruded film may have a thickness of 20 to 80 μm.

[0026] In one embodiment of the present invention, the high-density polyethylene (HDPE) resin may have a density of 0.950 to 0.960 g / cm3 and an MFR (190°C, 2.16 kgf) of 0.01 to 0.5 g / 10 min.

[0027] If the density of the above high-density polyethylene (HDPE) resin is less than 0.950 g / cm3, the mechanical properties of the blown film deteriorate, and if it exceeds 0.960 g / cm3, the elasticity, flexibility, extensibility, and impact resistance deteriorate.

[0028] If the MFR (190°C, 2.16 kgf) of the above high-density polyethylene (HDPE) resin is less than 0.01 g / 10 min, the formability of the blown film deteriorates, and if the MFR (190°C, 2.16 kgf) exceeds 0.5 g / 10 min, the mechanical properties of the blown film deteriorate.

[0029] In one embodiment of the present invention, the thickness of the outer layer may be 40 to 160 μm.

[0030] In one embodiment of the present invention, the adhesive layer may include a low-density polyethylene (LDPE) resin, an acrylate, or a polyurethane.

[0031] In one embodiment of the present invention, the low-density polyethylene (LDPE) resin may have a density of 0.915 to 0.930 g / cm3 and an MFR (190°C, 2.16 kgf) of 1 to 8 g / 10 min.

[0032] If the density of the above low-density polyethylene (LDPE) resin is less than 0.915 g / cm3, the mechanical properties of the blown film deteriorate, and if it exceeds 0.930 g / cm3, the elasticity, flexibility, extensibility, and impact resistance deteriorate. Preferably, the density may be 0.918 g / cm3.

[0033] If the MFR (190°C, 2.16 kgf) of the above low-density polyethylene (LDPE) resin is less than 1 g / 10 min, the formability of the blown film deteriorates, and if the MI exceeds 8 g / 10 min, the mechanical properties of the blown film deteriorate. Preferably, the MFR (190°C, 2.16 kgf) may be 7.2 g / 10 min.

[0034] In one embodiment of the present invention, the adhesive layer may be T-die extrusion coated to a thickness of 5 to 15 μm.

[0035] In one embodiment of the present invention, ozone treatment may be performed before formation of the adhesive layer to improve interlayer adhesion between the HDPE outer layer and the LDPE adhesive layer, which have no interlayer adhesion.

[0036] In one embodiment of the present invention, the ozone treatment may be performed at a flow rate of 100 to 200 ml / min. Preferably, high adhesion can be achieved by performing ozone treatment at a flow rate of 120 to 150 ml / min.

[0037] In one embodiment of the present invention, corona treatment may be performed before formation of the adhesive layer to improve interlayer adhesion between the HDPE outer layer and the LDPE adhesive layer.

[0038] The packaging material of the present invention includes a middle layer comprising ethylene vinyl alcohol (EVOH) resin on the outer layer to impart barrier properties and oxygen and water vapor barrier properties.

[0039] In one embodiment of the present invention, the multilayer may have a structure in which an adhesive LDPE layer, a tie resin layer, an ethylene vinyl alcohol (EVOH) resin layer, a tie resin layer, and an adhesive LDPE layer are sequentially laminated.

[0040] The thickness of the above adhesive LDPE layer may be 10 to 20 μm, the thickness of the Tie Resin layer may be 3 to 5 μm, and the thickness of the ethylene vinyl alcohol (EVOH) resin layer may be 6 to 8 μm.

[0041] Preferably, the above-mentioned layer can be T-die extrusion coated with a thickness of 32 to 52 μm.

[0042] In one embodiment of the present invention, the thickness deviation of the T-die extrusion coated layer can have good smoothness at the level of 1 to 2%.

[0043] In one embodiment of the present invention, the content of ethylene vinyl alcohol (EVOH) resin in the multilayer may be 5% or less of the total layer. Therefore, the packaging material of the present invention may be recognized as a single material.

[0044] In one embodiment of the present invention, the ethylene vinyl alcohol (EVOH) resin in the middle layer may be 27 to 44 mol%, have a density of 1.12 to 1.21 g / cm3, and have an MFR (190°C, 2.16 kgf) of 1 to 8 g / 10 min. mol% refers to the ethylene content.

[0045] The present invention uses an ethylene vinyl alcohol (EVOH) resin having an ethylene content of 27 to 44 mol% in the middle layer, thereby increasing the oxygen barrier property of the middle layer to 0.1 to 1.0 cc / m. 2 / 24hr, and the vapor barrier property is 1.0~5.0g / m 2 / 24hr can be implemented. Preferably, 27 mol% ethylene vinyl alcohol (EVOH) resin is used.

[0046] Preferably, the ethylene vinyl alcohol (EVOH) resin may have a density of 1.12 to 1.19 g / cm3 and an MFR (190°C, 2.16 kgf) of 3 to 5 g / 10 min.

[0047] In one embodiment of the present invention, the multilayer has an OTR barrier performance of 0.1 to 0.5 cc / m 2 ·Can have a day value.

[0048] In one embodiment of the present invention, ozone treatment may be performed prior to formation of the adhesive layer to improve interlayer adhesion between the HDPE outer layer and the middle layer, which have no interlayer adhesion.

[0049] In one embodiment of the present invention, the ozone treatment may be performed at a flow rate of 100 to 200 ml / min. Preferably, high adhesion can be achieved by performing ozone treatment at a flow rate of 120 to 150 ml / min.

[0050] In one embodiment of the present invention, corona treatment may be performed before formation of the adhesive layer to improve interlayer adhesion between the HDPE outer layer and the middle layer.

[0051] The packaging material of the present invention includes an inner layer formed on the middle layer as an ultra-low temperature sealing layer and containing linear low density polyethylene (LLDPE) resin.

[0052] In one embodiment of the present invention, the linear low-density polyethylene (LLDPE) resin has a density of 0.870 to 0.940 g / cm 3 And, MFR (190℃, 2.16kgf) may be 1~5g / 10min.

[0053] Preferably, the linear low-density polyethylene (LLDPE) resin has a density of 0.900 to 0.920 g / cm 3 And, MFR (190℃, 2.16kgf) may be 1~2g / 10min.

[0054] In one embodiment of the present invention, the thickness of the inner layer may be 30 to 80 μm.

[0055] The above packaging material can be used for feed packaging or food packaging.

[0056] The above packaging material is made of a single material and can be recycled.

[0057] The above packaging material can be used for packaging with a relatively high load of contents of 3 kg or more.

[0058] In addition, the present invention provides a method for manufacturing a packaging material, including the steps of: cutting a blown extruded film using a high-density polyethylene (HDPE) resin into a spiral shape at an angle of 1° to 30° to manufacture a slant-cut film; extrusion-coating an adhesive resin on the slant-cut film, and then laminating and bonding another sheet of the slant-cut film so that the directional grains of the films intersect at an angle of 1° to 30° to form an outer layer; sequentially laminating an adhesive LDPE layer, a tie resin layer, an ethylene vinyl alcohol (EVOH) resin layer, a tie resin layer, and an adhesive LDPE layer on the outer layer to form a middle layer; and forming an inner layer including a linear low-density polyethylene (LLDPE) resin on the middle layer.

[0059] A composite barrier film manufacturing device can be used in the method for manufacturing the packaging material of the present invention. As an example, the composite barrier film manufacturing device illustrated in Fig. 2 can be used.

[0060] According to the present invention, a packaging material in the form of a composite barrier film can be manufactured at high speed. Conventionally, composite barrier films were manufactured at a speed of 50 to 150 m / min using a dry laminating machine. However, according to the present invention, composite barrier films can be manufactured at a speed of 100 to 250 m / min.

[0061] Furthermore, the present invention enables the production of multi-layer packaging films in a single, in-line process, eliminating the need for a curing step, thereby reducing the total manufacturing time. Using a dry laminating machine, at least three passes were required, followed by a curing step (40-60°C, 3 days) after laminating.

[0062] In addition, according to the present invention, a composite barrier film having a good thickness deviation (within 1 to 2 μm) can be manufactured by applying an automated thickness measurement and control device.

[0063] Hereinafter, the present invention will be described in more detail through specific examples and comparative examples.

[0064]

[0065] [ingredient]

[0066] As a high-density polyethylene (HDPE) product, MFR (190℃, 2.16kgf) 0.05g / 10min, density 0.956g / cm 3 SK products were used.

[0067] Low-density polyethylene (LDPE) products have an MFR (190℃, 2.16kgf) of 7.2g / 10min and a density of 0.918g / cm 3 LG Chemical products were used.

[0068] Linear low-density polyethylene (LLDPE) products have an MFR (190℃, 2.16kgf) of 1.0g / 10min and a density of 0.918g / cm 2 LG Chemical products were used.

[0069] As an adhesive resin product, MFR (190℃, 2.16kgf) 9.0g / 10min, density 0.92g / cm 3 Mitsui Chemicals products were used.

[0070] Ethylene vinyl alcohol (EVOH) products have an MFR (190℃, 2.16kgf) of 8.0g / 10min and a density of 1.21g / cm 3 Kuraray products were used.

[0071]

[0072] <Manufacturing Example 1> Manufacturing of HDPE film

[0073] High-density polyethylene (HDPE) (MFR (190℃, 2.16kgf): 0.05g / 10min, density 0.956g / cm 3 ) 300 kg was fed into the extruder of a blown film forming machine, and a blown film with a thickness of 20 ㎛ was manufactured under the following conditions.

[0074] <Film forming conditions>

[0075] Extrusion cylinder temperature: 170~190℃, die temperature: 170~190℃

[0076] Extrusion capacity: 100 kg / hour,

[0077] Circular die: 200mm, die gap width: 0.7mm,

[0078] Blow-up ratio: 5~8, take-up speed: 30~40m / min.

[0079] Stretch ratio (MD stretch ratio / TD stretch ratio): 6:4

[0080]

[0081] In cooling the tube bubble, the neck of the bubble was gradually cooled to 80°C by blowing air from the first blower, the expanded portion of the bubble was gradually cooled to 60°C by blowing air from the second blower, the frost line region was gradually cooled to 40°C by blowing air from the third blower, and the bubble region was maintained at 40°C to manufacture a cylindrical plastic film.

[0082] Next, an HDPE film cut at an angle of 0° was manufactured.

[0083] <Manufacturing Example 2> Manufacturing of HDPE film

[0084] An HDPE film was manufactured using the same method as Manufacturing Example 1, except that it was cut at an angle of 30° and then slanted.

[0085] <Manufacturing Example 3> Manufacturing of biaxially oriented polyethylene (BOPE) film

[0086] High-density polyethylene (HDPE) (MFR (190℃, 2.16kgf): 1.0g / 10min, density 0.947g / cm 3 ) 300 kg was fed into the extruder of a T-die film forming machine, and a biaxially oriented polyethylene (BOPE) film with a thickness of 30 ㎛ was manufactured under the following conditions.

[0087] <Film forming conditions>

[0088] Extrusion cylinder temperature: 170~200℃, die temperature: 170~200℃

[0089] Extrusion capacity: 100 kg / hour,

[0090] T-die: 300mm, die gap width: 1.0mm,

[0091] Pick-up speed: 30~40m / min.

[0092] Stretch ratio (MD stretch ratio / TD stretch ratio): 8:6

[0093]

[0094] <Example 1> Manufacturing of packaging material

[0095] After ozone treatment at a flow rate of 100 to 200 ml / min on the HDPE film manufactured in Manufacturing Example 1, LDPE resin was extrusion-coated, and the HDPE film manufactured in Manufacturing Example 1 was laminated at an angle of 0° and then laminated (40 μm). Thereafter, an adhesive LDPE layer (10 μm), a tie resin layer (3 μm), an ethylene vinyl alcohol (EVOH) resin layer (6 μm), a tie resin layer (3 μm), and an adhesive LDPE layer (10 μm) were sequentially coextruded and laminated. Then, a linear low-density polyethylene (LLDPE) resin film (30 μm) was laminated to manufacture a multilayer packaging material.

[0096] <Example 2> Manufacturing of packaging material

[0097] After ozone treatment at a flow rate of 100 to 200 ml / min on the HDPE film manufactured in Manufacturing Example 2, LDPE resin was extrusion-coated, and the HDPE film manufactured in Manufacturing Example 2 was laminated at an angle of 30° and then laminated (40 μm). Thereafter, an adhesive LDPE layer (10 μm), a tie resin layer (3 μm), an ethylene vinyl alcohol (EVOH) resin layer (6 μm), a tie resin layer (3 μm), and an adhesive LDPE layer (10 μm) were sequentially coextruded and laminated. Next, a linear low-density polyethylene (LLDPE) resin film (30 μm) was laminated to manufacture a multilayer packaging material.

[0098]

[0099] <Comparative Example 1>

[0100] An adhesive LDPE layer (10 μm), a tie resin layer (3 μm), an ethylene vinyl alcohol (EVOH) resin layer (6 μm), a tie resin layer (3 μm), and an adhesive LDPE layer (10 μm) were sequentially coextruded and laminated onto the HDPE film (20 μm) manufactured in Manufacturing Example 1. Then, a linear low-density polyethylene (LLDPE) resin film (30 μm) was laminated to manufacture a multilayer packaging material.

[0101] <Comparative Example 2>

[0102] An adhesive LDPE layer (10 μm), a tie resin layer (3 μm), an ethylene vinyl alcohol (EVOH) resin layer (6 μm), a tie resin layer (3 μm), and an adhesive LDPE layer (10 μm) were sequentially coextruded and laminated onto the biaxially oriented polyethylene (BOPE) film (30 μm) manufactured in Manufacturing Example 3. Then, a linear low-density polyethylene (LLDPE) resin film (30 μm) was laminated to manufacture a multilayer packaging material.

[0103] <Comparative Example 3>

[0104] High-density polyethylene (HDPE) (MFR (190℃, 2.16kgf): 0.05g / 110min, density 0.956g / cm 3 ) 300 kg was fed into the extruder of a blown film forming machine, and a blown film with a thickness of 20 ㎛ was manufactured under the following conditions.

[0105] <Film forming conditions>

[0106] Extrusion cylinder temperature: 170~190℃, die temperature: 170~190℃

[0107] Extrusion capacity: 100 kg / hour,

[0108] Circular die: 200mm, die gap width: 0.7mm,

[0109] Blow-up ratio: 5~8, take-up speed: 30~40m / min.

[0110] Stretch ratio (MD stretch ratio / TD stretch ratio): 6:4

[0111]

[0112] In cooling the tube bubble, the neck of the bubble was gradually cooled to 80°C by blowing air from the first blower, the expanded portion of the bubble was gradually cooled to 60°C by blowing air from the second blower, the frost line region was gradually cooled to 40°C by blowing air from the third blower, and the bubble region was maintained at 40°C to manufacture a cylindrical plastic film.

[0113] Next, a slant-cut HDPE film was manufactured by cutting at a 90° angle.

[0114] Next, after ozone treatment at a flow rate of 100 to 200 ml / min, LDPE resin was extrusion-coated and another HDPE film manufactured was laminated at a 90° angle and then laminated (40 μm). After that, an adhesive LDPE layer (10 μm), a tie resin layer (3 μm), an ethylene vinyl alcohol (EVOH) resin layer (6 μm), a tie resin layer (3 μm), and an adhesive LDPE layer (10 μm) were sequentially coextruded and laminated. Then, a linear low-density polyethylene (LLDPE) resin film (32 μm) was laminated to manufacture a multilayer packaging material.

[0115]

[0116] Experimental Example 1

[0117] The tear strength of the specimens manufactured in the examples and comparative examples was measured using the ASTM D624 method, and the results are shown in Table 1 below.

[0118]

[0119]

[0120] As shown in Table 1 above, it was confirmed that the specimens of Examples 1 to 2 and Example 3 had low tensile strength only in the MD direction and high tensile strength in the TD direction.

[0121] As shown in Fig. 3, in the MD direction cut photo and the TD direction cut photo of the packaging material according to Example 2 of the present invention, an easy cut occurred in the MD direction, and the film was torn as it stretched in the TD direction.

[0122] On the other hand, the specimens of Comparative Example 1, which is a non-laminated HDPE film, and Comparative Example 2, which is a non-laminated BOPE film, have low tear strengths in both the MD and TD directions, making them difficult to use as packaging materials.

[0123] In addition, the specimen of Comparative Example 3 with a bonding angle of 90° had high tensile strength in both the MD and TD directions, making easy cut impossible in both the MD and TD directions.

[0124] Therefore, it was confirmed that the packaging material of the present invention has excellent easy-cut characteristics and barrier characteristics and is a packaging material made of a single material.

[0125] [Explanation of symbols]

[0126] 10: Packaging material, 21, 22: Slant-cut film, 23: Adhesive layer, 20: Outer layer, 30: Middle layer, 40: Inner layer

Claims

1. An outer layer in which a plurality of film layers, each of which is cut at an angle of 0° to 30° to form a spiral shape using a blown extruded film made of high-density polyethylene (HDPE) resin, are laminated at an angle of 0° to 30°; An adhesive layer formed between the above laminated film layers; A middle layer formed on the outer layer and containing ethylene vinyl alcohol (EVOH) resin; and A packaging material formed on the above-mentioned multilayer and having an inner layer comprising linear low-density polyethylene (LLDPE) resin.

2. In paragraph 1, The above blown extruded film is a packaging material having a stretching ratio (MD stretching ratio / TD stretching ratio) within a range of 5:5 to 8:

6.

3. In paragraph 1, The above blown extruded film is a packaging material having a thickness of 20 to 80 μm.

4. In paragraph 1, The above high-density polyethylene (HDPE) resin is a packaging material having a density of 0.950 to 0.960 g / cm3 and an MFR (190°C, 2.16 kgf) of 0.01 to 0.5 g / 10 min.

5. In paragraph 1, A packaging material having a thickness of the outer layer of 40 to 160㎛.

6. In paragraph 1, A packaging material wherein the adhesive layer comprises low-density polyethylene (LDPE) resin, acrylate or polyurethane.

7. In paragraph 6, The above low-density polyethylene (LDPE) resin is a packaging material having a density of 0.915 to 0.930 g / cm3 and an MFR (190°C, 2.16 kgf) of 1 to 8 g / 10 min.

8. In paragraph 1, A packaging material in which the above adhesive layer is T-die extrusion coated to a thickness of 5 to 15 μm.

9. In paragraph 1, Packaging material in which ozone treatment has been performed before formation of the above adhesive layer.

10. In paragraph 1, A packaging material having a structure in which the above-mentioned multilayer is sequentially laminated with an adhesive LDPE layer, a tie resin layer, an ethylene vinyl alcohol (EVOH) resin layer, a tie resin layer, and an adhesive LDPE layer.

11. In paragraph 10, A packaging material wherein the total thickness of the above-mentioned multilayer is 32 to 52 ㎛, the thickness of the adhesive LDPE layer is 10 to 20 ㎛, the thickness of the tie resin layer is 3 to 5 ㎛, and the thickness of the ethylene vinyl alcohol (EVOH) resin layer is 6 to 8 ㎛.

12. In paragraph 1, A packaging material having an ethylene vinyl alcohol (EVOH) resin content of 5% or less in the above-mentioned multilayer.

13. In paragraph 1, In the above-mentioned multilayer, ethylene vinyl alcohol (EVOH) resin is 27 to 44 mol% and has a density of 1.12 to 1.21 g / cm 3 And, packaging material having MFR (190℃, 2.16kgf) of 1 to 8g / 10min.

14. In paragraph 1, A packaging material in which the above linear low-density polyethylene (LLDPE) resin has a density of 0.870 to 0.940 g / cm3 and an MFR (190°C, 2.16 kgf) of 1 to 5 g / 10 min.

15. In paragraph 1, A packaging material having an inner layer thickness of 30 to 80 μm and used as an ultra-low temperature sealing layer.

16. In paragraph 1, Packaging material used for packaging feed or food.

17. In paragraph 1, Packaging materials that can be recycled.

18. A step of manufacturing a cut film by cutting a blown extruded film using a high-density polyethylene (HDPE) resin at an angle of 0° to 30° to form a spiral shape; A step of forming an outer layer by extruding and coating an adhesive resin on the cut film and then laminating and bonding another sheet of the cut film so that the directional grains of the films intersect at an angle of 0° to 30°; A step of forming a middle layer by sequentially laminating an adhesive LDPE layer, a tie resin layer, an ethylene vinyl alcohol (EVOH) resin layer, a tie resin layer, and an adhesive LDPE layer on the outer layer; and A method for manufacturing a packaging material, comprising the step of forming an inner layer comprising a linear low-density polyethylene (LLDPE) resin on the above-mentioned middle layer.

Images