Transparent dual transmission resistant high barrier film and packaging laminate using the same

Abstract

The present invention relates to a transparent dual-protection high barrier film having excellence in blocking moisture and oxygen, and a packaging material laminate using the same. The transparent dual-protection high barrier film according to the present invention comprises a first synthetic resin layer made of ethylene as a main raw material and blocking oxygen and moisture, an oxygen barrier layer formed on one side of the first synthetic resin layer, a second synthetic resin layer formed facing the first synthetic resin layer with the oxygen barrier layer in the center, and an tie layer formed between the first synthetic resin layer and the oxygen barrier layer and between the second synthetic resin layer and the oxygen barrier layer, respectively, to bond the layers.

Description

[0001] Transparent Dual Transmission Resistant High Barrier Film and Packaging Laminate Using the Same

[0002] Technical Field

[0003] This invention relates to a barrier film used as a packaging material for food or daily necessities, and more particularly to a transparent dual-protection high barrier film having excellent moisture and oxygen barrier properties, and to a packaging material laminate using the same.

[0004] Background Art

[0005] A laminate is made of several thin films glued together, sometimes called a laminated film.

[0006] In general, food is broken down into small molecules by the action of microorganisms, light, oxygen, chemicals, etc. and loses its original quality such as taste, smell, color, and appearance. This phenomenon is called spoilage or deterioration, and in order to control the deterioration of quality, it is important to minimize microbial and chemical contamination through hygienic manufacturing processes and minimize the contact of the contents with deterioration factors (light, moisture, oxygen, etc. ) that affect the food contents during distribution.

[0007] In particular, the moisture content of the foods and the oxygen concentration inside the packaging directly affect the growth of microorganisms and the spoilage of the food, so the use of packaging materials with barrier properties against moisture and oxygen is required for stable storage and distribution of food contents. Currently, barrier films for packaging, which are commonly used in the food packaging industry, are manufactured by coating a thin layer of solvent-based coatings such as polyvinyl alcohol (PVA) on a base film made of polyethylene ( PE) or polypropylene (PP) •

[0008] In this case, the barrier layer formed by solvent-based coatings is usually a film using polyvinyl alcohol ( PVA) , but aluminum foil is used in applications requiring higher barrier properties .

[0009] FIG. 1 is a cross-sectional view of a conventional packaging laminate made of aluminum.

[0010] As illustrated in FIG. 1, a conventional packaging laminate 10 is manufactured in the form of a film with a multi-layer structure, including a PET (Polyester; 11) , a barrier layer 13, a PE layer (Polyethylene; 15) , and adhesive layers 12, 14 positioned between the layers for adhesion between the layers, to provide barrier properties in accordance with product characteristics.

[0011] In particular, barrier layer 13 is made of aluminum foil (AL) , metalized polyester (VM-PET) , AlOx PET, etc. to provide excellent oxygen and moisture barrier properties.

[0012] As such, the packaging laminate 10 made of aluminum foil has excellent barrier properties that prevent oxygen and water vapor from deteriorating the quality, and is applied not only in the food industry, but also in the medical industry (preservation of freshness, such as IV solution pouches) and the electronic device industry (moisture-proof) .

[0013] However, the conventional packaging laminate 10 made of aluminum foil has the disadvantage of being non-transparent due to the nature of the aluminum foil. Therefore, it is not possible to accurately identify the contents in the packaging.

[0014] In addition, the conventional packaging laminate 10 using aluminum foil has a problem of durability due to the characteristics of aluminum foil, which is easily torn and crumpled once pressure is applied ( impact , tearing, bending fatigue, abrasion) .

[0015] In addition, the conventional packaging laminate 10 using aluminum foil is about 1.5 to 2 times more expensive than the general packaging film, so it has a disadvantage that it is still mainly used for high-end food packaging.

[0016] In addition, the conventional packaging laminate 10 using aluminum foil is not an environmentally friendly material and causes continuous problems with environmental pollution when incinerated .

[0017] In addition, the conventional packaging laminate 10 using aluminum foil uses a solvent (VOC) as an adhesive to bond the PET 11 and the barrier layer 13, and the barrier layer 13 and the PE layer 15, and the solvent between the PET 11 and the barrier layer 13 is blocked by the barrier layer 13, but the solvent between the barrier layer 13 and the PE layer 15 migrates to the food inside, which is a major problem in terms of food safety.

[0018] Disclosure of the Invention

[0019] Technical Problems

[0020] The present invention aims to solve the above-mentioned problems and provides an environmental-friendly, transparent, dual-protection high barrier film that has excellent oxygen and moisture barrier properties, as well as a transparent packaging that enables identification of packaging contents.

[0021] Furthermore, it is an object of the present invention to provide a packaging laminate that can be manufactured by a simple process utilizing the above-mentioned transparent dualprotection high barrier film.

[0022] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be apparent to those who are having packaging knowledge in the technical field to which this invention belongs from the following description.

[0023] Technical Solutions

[0024] To accomplish the above-mentioned objects, a transparent dual-protection high barrier film according to an embodiment of the present invention comprises, as a barrier film, a first synthetic resin layer made of ethylene as a main raw material to block oxygen and moisture, an oxygen barrier layer formed on one side of the first synthetic resin layer, a second synthetic resin layer formed facing the first synthetic resin layer with the oxygen barrier layer in the center, and an tie layer formed between the first synthetic resin layer and the oxygen barrier layer and between the second synthetic resin layer and the oxygen barrier layer, respectively, to bond the layers.

[0025] The oxygen barrier layer may comprise a transparent ethylene vinyl alcohol (EVOH) , which is a copolymer of polyethylene and vinyl acetate .

[0026] Furthermore, the oxygen barrier layer may have a content of ethylene of from 29 mol% to 44 mol%, considering its oxygen barrier properties and thermal stability.

[0027] Furthermore, the first synthetic resin layer and the second synthetic resin layer may comprise at least one of a transparent linear low-density polyethylene (LLDPE or LDPE) layer having oxygen barrier properties, a translucent high-density polyethylene (HDPE) layer having moisture barrier properties.

[0028] In this case, the high-density polyethylene layer and the low-density polyethylene layer of the first synthetic resin layer, and the high-density polyethylene layer and the low- density polyethylene of the second synthetic resin layer may be formed symmetrically with respect to each other with the oxygen barrier layer in center.

[0029] Furthermore, when the first synthetic resin layer and the second synthetic resin layer may comprise two or more multilayer structures including both the linear low-density polyethylene layer and the high-density polyethylene layer, they have alternately positioned each other to improve transparency, such as a linear low-density polyethylene layer ( transparent ) - a high-density polyethylene layer (opaque) - a linear low-density polyethylene layer (transparent ) .

[0030] A packaging laminate utilizing a transparent dualprotection high barrier film according to another embodiment of the present invention, comprising: a base film; a transparent dual-protection high barrier film according to claim 1; an adhesive layer forming a volatile organic compound (VOC) on the base film to bond the base film to the transparent dualprotection high barrier film.

[0031] In this case, the base film may comprise one or more of a polyester ( PET ) film, a polypropylene ( PP ) film, a nylon film, and a polyethylene ( PE) film.

[0032] The polypropylene ( PP) film may comprise a biaxially oriented polypropylene (BOPP) film, the nylon film may comprise a biaxially oriented polyamide (BOPA) film, and the polyethylene film may comprise a biaxially oriented polyethylene (BOPE) film and a mono-axially oriented polyethylene (MOPE) film. Furthermore, the transparent dual-protection high barrier film may prevent components of the adhesive organic solvent from entering the foods inside of the package.

[0033] Advantageous Effects of the Invention

[0034] According to the examples of the present invention, it is proven to block oxygen migration into the packaging laminate while preventing moisture loss of the product (contents) in the packaging laminate, thereby maintaining the freshness of the color, texture, and taste of the food for a longer period.

[0035] Furthermore, according to the examples of the present invention, the transparency of the high barrier film allows the contents to be viewed, thereby enhancing the effectiveness of product display, and stimulating consumer desire to purchase. This effect makes it possible to replace the existing nontransparent aluminum foil.

[0036] In addition, according to the examples of the present invention, the multi-layer barrier structure of the high barrier film enhances durability and solves the problem of low crack resistance of barrier films using conventional aluminum foil.

[0037] Furthermore, according to the examples of the present invention, the adhesive solvent used for bonding between the base film of the packaging laminate and the high barrier film is blocked by the multi-layer barrier structure of the high barrier film, thereby preventing harmful substances from entering the contents inside of the package, thereby ensuring the food safety Brief Description of Drawings

[0038] FIG. 1 is a cross-sectional view of a conventional packaging laminate made of aluminum.

[0039] FIG. 2 is a diagram illustrating a packaging laminate using a transparent dual-protection high barrier film according to the examples of the present invention.

[0040] FIG. 3 is a drawing to illustrate the functionality of a packaging laminate utilizing a transparent dual-protection high barrier film according to the examples of the present invention.

[0041] FIG. 4 is a detailed cross-sectional view of a transparent dual-protection high barrier film according to the examples of the present invention.

[0042] FIG. 5 is a conceptual diagram illustrating process steps describing a method of manufacturing a transparent dualprotection high barrier film according to the examples of the present invention.

[0043] Best Mode for Invention

[0044] The present invention will be described in more detail below with reference to the drawings .

[0045] The high barrier film referred to in the embodiment of the present invention refers to a film having the ability to block water vapor transmission rate of 1.5 g / m2 or less per day. In recent years, as the market for meals, which are prepared at home by purchasing side dishes or bento boxes at supermarkets or convenience stores, has expanded due to the increase in dualincome and single-person households, high barrier films have been attracting attention in the food packaging film market as packaging films with excellent freshness preservation effects.

[0046] Specifically, embodiments of the present invention disclose a high barrier film with excellent barrier properties to oxygen and moisture.

[0047] FIG. 2 is a drawing illustrating a packaging laminate utilizing a transparent dual-protection high barrier film according to an embodiment of the present invention, and FIG. 3 is a drawing to illustrate the functionality of a packaging laminate (composite) utilizing a transparent dual-protection high barrier film according to the examples of the present invention .

[0048] FIG. 2 illustrates an example of the application of a packaging laminate 100 according to an embodiment of the present invention as food packaging.

[0049] As shown, the packaging laminate 100 according to an embodiment of this invention is a transparent film that allows for easy identification of the food product (contents) in the package. The basic packaging sheet 100 is characterized by being a transparent film, although it may be made of a translucent film including a printed paper (115 in FIG. 3) with the food name, handling instructions, date of manufacture, etc. as needed The packaging laminate 100 includes a base film 110, an adhesive layer 120, and a clear dual-protection high barrier film 130.

[0050] The base film 110 can be a PET film made of polyester (PET) as the main raw material. PET film is thinner, has better strength and heat resistance, and is more resistant to external scratches than conventional base films. Therefore, base film 110 is advantageous as the outer surface of the packaging when the packaging laminate 100 is manufactured as a food packaging.

[0051] The base film 110 is preferably, but not exclusively, a PET film having excellent transparency, heat resistance, high tensile strength, excellent dimensional stability, impermeability, moisture resistance, water resistance, and chemical resistance suitable for packaging and metallizing, and any film that is transparent and resistant to external scratches (tearing) will be suitable. For example, in addition to polyester (PET) films, one or more of polypropylene films, such as biaxially oriented polypropylene (BOPP) films, or nylon films, such as biaxially oriented polyamide (BOPA) films, and polyethylene (PE) films, such as biaxially oriented polyethylene (BOPE) films and mono-axially oriented polyethylene (MOPE) films can be used.

[0052] The adhesive layer 120 forms a volatile organic compound (VOC) on the base film 110 that serves to bond the base film 110 and the transparent dual-protection high barrier film 130.

[0053] The transparent dual-protection high barrier film 130 is a transparent film and has a barrier function to protect the contents from things such as moisture (H2O) penetration or oxygen (02) penetration, as shown in FIG. 3.

[0054] In addition, the transparent dual-protection high barrier film 130 prevents volatile organic compounds (VOCs) from the adhesive layer 120 from migrating into the contents.

[0055] When the packaging laminate 100 is manufactured as a food packaging, the base film 110 is positioned on the outer side of the package and the transparent dual-protection high barrier film 130 is positioned on the inner side that contacts the food, where the transparent dual-protection high barrier film 130 prevents the ingress of volatile organic compounds, which can improve food safety.

[0056] Thus, the packaging laminate 100 according to an embodiment of this invention is a functional film that can secure the freshness and safety of food by blocking moisture and oxygen permeation, as well as the influx of volatile organic compounds harmful to food.

[0057] Furthermore, the packaging laminate 100 according to an embodiment of this invention is an environmentally friendly material and is functional with excellent moisture and oxygen barrier properties and is therefore sufficient as an alternative to conventional packaging laminates using aluminum foil.

[0058] Furthermore, the packaging laminate 100 according to an embodiment of this invention can be manufactured by applying an organic solvent for adhesion to one side of the base film 110 and bonding a transparent dual-protection high barrier film 130 over the applied adhesive layer 120. Thus, the packaging laminate 100 according to an embodiment of this invention can shorten the manufacturing process compared to the manufacturing process of a packaging laminate using a conventional aluminum foil, thereby reducing processing costs.

[0059] The manufacturing process of a packaging laminate using a conventional aluminum foil requires two bonding processes to join the multi-layer structure, as shown in FIG. 1, while the packaging material laminate 100 according to an embodiment of this invention requires only one bonding process to join the PET film 110 and the transparent dual-protection high barrier film 130, thereby reducing the working time required for the manufacturing process.

[0060] FIG. 4 is a detailed cross-sectional view of a transparent dual-protection high barrier film according to an embodiment of the present invention.

[0061] The transparent dual-protection high barrier film 130 applied to a sheet of packaging material according to an embodiment of the present invention is a transparent barrier film having a multi-layer structure and providing a dualprotection to oxygen and moisture.

[0062] As shown, the transparent dual-protection high barrier film 130 includes first and second synthetic resin layers 133, 139, an oxygen barrier layer 135 positioned therebetween, and a tie layer 134, 136 for bonding the layers together.

[0063] The first synthetic resin layer 133 is made of ethylene as the main raw material and has a barrier property to block oxygen and moisture.

[0064] The second synthetic resin layer 139, like the first synthetic resin layer 133, is made of ethylene as the main raw material and has barrier properties to block oxygen and moisture In this case, the second synthetic resin layer 139 is formed to face the first synthetic resin layer 133 with the oxygen barrier layer 135 in the center.

[0065] The tie layers 134, 136 are formed between the first synthetic resin layer 133 and the oxygen barrier layer 135, and between the second synthetic resin layer 139 and the oxygen barrier layer 135, respectively, and serve to bond the layers.

[0066] The oxygen barrier layer 135 formed on one side of the first synthetic resin layer 133 may be ethylene vinyl alcohol (EVOH) , which has excellent oxygen barrier properties and is transparent.

[0067] Ethylene vinyl alcohol (EVOH) is a copolymer of polyethylene and vinyl acetate, which is formed by the hydrolysis of polyethylene vinyl acetate obtained by the gas phase copolymerization of ethylene and vinyl acetate, which are usually in solution. Ethylene Vinyl Alcohol (EVOH) is known to have the best gas barrier protection against gases such as oxygen, nitrogen, and carbon dioxide. In addition, EVOH is a transparent, glossy thermoplastic copolymer.

[0068] The oxygen barrier layer 135 according to an embodiment of the present invention may be ethylene vinyl alcohol (EVOH) having these properties, but with a content of ethylene from 29 mol% to 44 mol%, considering its oxygen barrier properties and thermal stability .

[0069] The oxygen barrier properties of ethylene vinyl alcohol (EVOH) are strongly influenced by the amount of water that is absorbed, and experiments calculating the singlemolecule absorption of water into ethylene vinyl alcohol have shown that the amount of water absorbed depends on the relative humidity .

[0070] At 0% relative humidity, the oxygen gas transmittance increases significantly with increasing ethylene content, but at 100% relative humidity, the oxygen gas transmittance is lowest at 44% ethylene content and increases significantly with decreasing ethylene content.

[0071] Therefore, the most efficient ethylene content of EVOH was found to be between 29 mol% and 44 mol%, considering both oxygen gas barrier properties and thermal stability (processing temperature in the molding machine) .

[0072] Here, 29 mol% has the highest alcohol content and therefore the best oxygen barrier properties, but it is difficult to produce films with higher content, so EVOH resins with 44 mol% can be used. EVOH resin with 29 mol% or less is very difficult to process with the current equipment in the EVOH manufacturing industry and is not economical, while 44 mol% or more is easy to process, but oxygen barrier properties may decrease rapidly.

[0073] The first synthetic resin layer 133 and the second synthetic resin layer 139 may include at least one of a transparent liner low density polyethylene (LLDPE) layer 131, 138, which has some moisture barrier properties, and a translucent high-density polyethylene (HDPE) layer 132, 137, which has much better moisture barrier properties.

[0074] When the first synthetic resin layer 133 and the second synthetic resin layer 139 equally comprise two or more layers, the laminated structure of the first and second synthetic resin layers 133, 139 is formed symmetrically with respect to the oxygen barrier layer 135. For example, if the first synthetic resin layer 133 is formed in the order of LLDPE layer-HDPE layer, the second synthetic resin layer 139 is arranged in the order of HDPE layer-LLDPE layer, and a multi-layer barrier structure can be formed in the order of LLDPE layer-HDPE layer-oxygen barrier layer-HDPE layer-LLDPE layer.

[0075] Furthermore, if the first synthetic resin layer 133 and the second synthetic resin layer 139 equally comprise two or more layers, it is preferable to stack them alternately with each other, such as LLDPE layer (transparent) - HDPE layer (opaque) - LLDPE layer (transparent) , to improve transparency based on light scattering theory.

[0076] The most preferred laminated structure, considering both the overall thickness and transparency of the transparent dualprotection high barrier film 130, is when the first synthetic resin layer 133 and the second synthetic resin layer 139 comprise one layer each of LLDPE layers 131, 138 and HDPE layers 132, 137, as shown. In this case, the HDPE layers 132, 137 are arranged to be bonded with the oxygen barrier layer 135 so that the LLDPE layer 131 and HDPE layer 132 of the first synthetic resin layer 133 and the HDPE layer 137 and LLDPE layer 138 of the second synthetic resin layer 139 are formed symmetrically with respect to the oxygen barrier layer 135.

[0077] Here, the LLDPE layers 131, 138 may be replaced with low density polyethylene (LDPE) .

[0078] Low-density polyethylene (LDPE) is also a moisture barrier and is a transparent solid at room temperature. LDPE has a density of 0.910 to 0.928 g / cm3, which makes it less dense than other materials. LDPE has a structure with many "branches," which is a molecular structure that resembles the branches of a tree. When the branching arrangement is stacked, there is more space between the molecules, resulting in an irregular arrangement of polyethylene molecules and a low degree of stacking between chains, resulting in low density. As such, low- density polyethylene (LDPE) is characterized by excellent water resistance, good heat retention, and transparency.

[0079] Liner Low Density Polyethylene (LLDPE) is a synthetic resin with similar properties to Low Density Polyethylene (LDPE) but is more flexible and tougher. LLDPE has significant advantages over low-density polyethylene (LDPE) in that it can achieve superior physical properties at lower thicknesses and has better transparency and heat resistance.

[0080] The HDPE layers 132, 137 are made of high-density polyethylene (HDPE) , which has the highest density of any ethylene-based synthetic resin. HDPE, like linear low-density polyethylene (LLDPE) , has a linear molecular structure and is polymerized from ethylene at a lower pressure using a catalyst to achieve a density of 0.94 to 0.97 g / cm3.

[0081] High-density polyethylene ( HDPE ) is a translucent, solid, synthetic resin with excellent strength, heat resistance, and moisture barrier properties. The higher the density of HDPE, the less transparent it becomes, but the better its moisture barrier properties. In other words, as HDPE becomes less transparent, it becomes more moisture barrier.

[0082] Therefore, an embodiment of this invention adopts high- density polyethylene (HDPE) , which has excellent moisture barrier properties even though it has low transparency but improves the transparency of translucent high-density polyethylene (HDPE) based on light scattering theory.

[0083] In other words, when the transparent LLDPE layer 131, 138 is bonded to both sides of the translucent HDPE layer 132, 137, light scattering occurs, and the light scattering makes it possible to see the back of the HDPE layer 132, 137, which appears to be opaque.

[0084] Light scattering control technology is a technique that allows you to see objects hidden by light scattering.

[0085] In an experiment called "The Rediscovery of Transparent Tape, " transparent tape was applied to an opaque glass window to make it clear. The transparent tape filled in the irregularities of the opaque glass, reducing light scattering.

[0086] The reason we can't see through the skin is not because light is absorbed by the skin, but because it is scattered. Since light scattering prevents us from seeing through the skin, the flip side is that controlling light scattering allows us to see through the skin.

[0087] This is the basic principle behind light scattering control technology: if you reflect light back as much as it scatters, you can solve the problem of not being able to see due to light scattering. One of the physics theories presented here is optical phase conjugation.

[0088] By utilizing phase conjugation and light scattering techniques, it is possible to clearly see objects on the other side of an obstacle, such as smoke or clouds, as well as objects hidden behind highly scattering objects such as human skin. However, this requires recording the information from the scattered light and accurately reflecting it back to the other side so that the light scattering from the obstacle in the middle of the object can be controlled.

[0089] In an embodiment of this invention, transparency is effectively improved by a three-layer structure, such as a transparent LLDPE layer - a translucent HDPE layer - a transparent LLDPE layer (or a transparent oxygen barrier layer) .

[0090] Similarly, in the field of solar panels for photovoltaic power generation, a transparent solar panel was recently developed by making a three-layer coextruded film of 10 pm of highly transparent Ionomer resin (DuPont Surlyn 1605) - 80 pm of opaque EBA resin - and 10 pm of highly transparent Ionomer resin (DuPont Surlyn 1605) . Solar panels that were previously formed as black panels have been developed as transparent and are being utilized as glass windows.

[0091] In accordance with this principle, the transparent dualprotection high barrier film 130 according to an embodiment of this invention is preferably laminated in the following order: LLDPE layer ( transparent ) - HDPE layer (translucent) - EVOH

[0092] (transparent) - HDPE layer (translucent ) - LLDPE layer ( transparent ) , If the first and second synthetic resin layers 133, 139 include two or more multilayer structures, it is preferable to improve the transparency by alternately laminating them with each other, such as LLDPE layer ( transparent ) - HDPE layer ( opaque ) - LLDPE layer (transparent) .

[0093] This principle (theory) is sometimes referred to as the "I Beam Effect" in North America and Europe, and the "H Beam Effect" in Asia.

[0094] FIG. 5 is a conceptual diagram illustrating process steps describing a method of manufacturing a transparent dualprotection high barrier film according to embodiments of the present invention. As shown, the transparent dual-protection high barrier film according to an embodiment of this invention may be manufactured by a coextruded blown type or a coextruded cast type to produce a film with a multilayer structure.

[0095] Co-extrusion is a processing method that uses two or more extruders to produce a film by simultaneously extruding each molten resin and laminating them in multiple layers in the molten state.

[0096] The purpose of coextrusion is to add multiple functions to a film produced in a single layer. In other words, one resin has one unique property, and to give it a new function, the existing resin and the resin with the new function coextruded to create a film with multiple functions.

[0097] In the coextruded blown type, each molten resin corresponding to the first synthetic resin layer (133 in FIG. 4) , the adhesive layer (134 in FIG.4) , the oxygen barrier layer (135 in FIG.4) , the tie layer (136 in FIG.4) , and the second synthetic resin layer (139 in FIG.4) is collected in a die and air is blown upward through an air ring. As the balloon-like bubble rises upward in the vertical direction, it is cooled by contact with the air, and the film cooled to room temperature is wound on the winding machine on the ground floor below to become a coextruded blown film.

[0098] This co-extrusion blowing method allows you to increase the productivity of products produced at high speeds by applying HFFS (Horizontal Form Fill Seal packaging machine) or VFFS (Vertical Form Fill Seal packaging machine) due to its strong heat resistance.

[0099] In the coextruded cast type, a large diameter casting roll (cooling roll) is located at the exit from which each resin is melted and exited, and the casting roll provides the effect of cooling each molten resin-laminated film. In other words, as each molten resin-laminated film moves on the casting roll, the resin in each layer is cooled to form a single layer of coextruded cast film.

[0100] This coextrusion casting method results in better transparency and gloss than coextruded blown films, with less thickness variation.

[0101] This invention includes coextruded films that can be manufactured by both the above methods.

[0102] The features, structures, effects, etc. described above are included in at least one embodiment of the present invention and are not necessarily limited to any one embodiment. Furthermore, the features, structures, effects, etc. exemplified in each embodiment may be combined or modified in other embodiments by those who are having ordinary knowledge in the field to which the embodiments belong. Accordingly, such combinations and modifications are to be construed as being within the scope of the present invention.

[0103] Furthermore, while the above description has been made with reference to embodiments, these are merely illustrative and do not limit the present invention, and those having ordinary skill in the field will recognize that many modifications and applications not illustrated are possible without departing from the essential features of the present invention. For example, each of the components specifically shown in the embodiments may be practiced with variations. And differences with respect to such variations and applications are to be construed as being within the scope of the invention as defined by the appended claims . Industrial Applicability

[0104] The present invention relates to a transparent dualprotection high barrier film composed of a transparent material having excellent oxygen and moisture barrier properties and enabling identification of the contents of the package, which can be used as a packaging for fresh food products by maintaining the freshness of the color, texture, and taste of the food for a long time.

[0105] In particular, the method of manufacturing the high barrier film using the co-extrusion technology of the present invention can improve the productivity of the product in accordance with the trend of high-speed and large-scale work, so it is highly applicable to packaging-related industries such as the food, medical (IV solution pouches, etc. ) , and electronic device (moisture-proof effect) . Furthermore, the high barrier film of the present invention is an eco-friendly material that can reduce the emission of chemicals that cause environmental pollution when incinerated, thus expanding its industrial applicability in line with the recent trend of carbon gas emission reduction and environmental protection.

Claims

Claims1. A transparent dual-protection high barrier film, comprising;As a barrier film,A first layer of synthetic resin, which is made of ethylene and repels oxygen and moisture;An oxygen barrier layer formed on one side of the first synthetic resin layer;A second synthetic resin layer formed facing the first synthetic resin layer with the oxygen barrier layer centered; andA tie layer formed between the first synthetic resin layer and the oxygen barrier layer and between the second synthetic resin layer and the oxygen barrier layer, respectively, to bond the layers .2 . The transparent dual-protection high barrier film of Claim 1, wherein the oxygen barrier layer comprises a transparent Ethylene Vinyl alcohol (EVOH) , which is a copolymer of polyethylene and vinyl acetate.

3. The transparent dual-protection high barrier film of Claim 2, wherein the oxygen barrier layer has a content of ethylene from 29 mol% to 44 mol%, considering oxygen barrier properties and thermal stability.4 . The transparent dual-protection high barrier film ofClaim 1, wherein the first synthetic resin layer and the second synthetic resin layer comprise at least one of a transparentlinear low-density polyethylene (LLDPE) layer having oxygen barrier properties, and a translucent high-density polyethylene (HDPE) layer having moisture barrier properties.

5. The transparent dual-protection high barrier film of Claim 4, wherein the high-density polyethylene layer and the low-density polyethylene layer of the first synthetic resin layer, and the high-density polyethylene layer and the low- density polyethylene layer of the second synthetic resin layer are formed symmetrically with respect to each other with respect to the oxygen barrier layer.

6. The transparent dual-protection high barrier film of Claim 4, Wherein the first synthetic resin layer and the second synthetic resin layer are are alternately stacked each other to improve transparency, such as a linear low-density polyethylene layer (transparent) - a high-density polyethylene layer (opaque) - a linear low-density polyethylene layer (transparent) , when it comprises two or more multilayer structures, including both the linear low-density polyethylene layer and the high-density polyethylene layer.

7. A packaging material laminate, comprising:Base film;A transparent dual-protection high barrier film according to Claim 1; andAn adhesive layer forming a volatile organic compound (VOC) on the base film to bond the base film to the transparent dualprotection high barrier film.8 . The packaging material laminate of Claim 7, wherein the base film is made of at least one of Polyester (PET) film, Polypropylene film, Nylon film, and Polyethylene (PE) film.

9. The packaging material laminate of Claim 8, wherein the polypropylene film comprises a biaxially oriented polypropylene (BOPP) film,Wherein the nylon film comprises a biaxially oriented polyamide (BOPA) film, andWherein the polyethylene film comprises a biaxially oriented polyethylene (BOPE) film and a mono-axially oriented polyethylene (MOPE) film.

10. The packaging material laminate of Claim 7, wherein the transparent dual-protection high barrier film prevents components of the volatile organic compound from entering the contents of the package.

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