KR20240076752A - Packing material based on single material and manufacturing method thereof - Google Patents

Abstract

This specification relates to a single material-based packaging material and a method of manufacturing the same. A packaging material based on a single material according to an embodiment of the present invention has excellent oxygen and moisture barrier properties, so product preservation is excellent, and it can be recycled as a recycled raw material based on a single material.

Description

Single material based packaging material and manufacturing method thereof {PACKING MATERIAL BASED ON SINGLE MATERIAL AND MANUFACTURING METHOD THEREOF}

Disclosed herein are single material-based packaging materials and methods for manufacturing the same.

Global plastic production has increased 200 times from the 1950s to 2020, of which waste plastic for packaging materials accounts for the largest proportion at 45%. According to the 'Global Plastic Outlook (2022)', the Organization for Economic Co-operation and Development (OECD) predicts that 35,000 Eiffel Towers can be made from plastic waste produced around the world in 2019, and that three times more plastic waste will accumulate in 2060 than now. There was also a warning that it could happen. The current socioeconomic system, which is dominated by “mass production-mass consumption-mass disposal,” has limitations in overcoming the environmental crisis we face. Accordingly, there is an urgent need to transition to a “resource circulation society” that minimizes the use of natural resources and energy by suppressing waste generation throughout the entire process, including production and distribution, and returning recyclable resources from generated waste to the cycle of economic activities. From the above perspective, technology to reduce and recycle packaging waste is absolutely necessary, and for this to happen, materials and manufacturing technologies that replace barrier films in packaging materials must be developed first.

In general, flexible packaging materials use aluminum foil and aluminum-deposited PET film depending on the material composition to provide barrier properties. Although these films have excellent barrier properties, they are difficult to recycle because they are made of composite materials, and most of them are recovered as solid fuel for heat recovery, thereby emitting a large amount of environmental pollutants. In this way, when packaging materials using metal-based films are replaced with plastic films with barrier properties and single packaging materials grafted thereon, there are greenhouse gas reduction effects and recycling advantages, which can create a new growth engine as a new material for eco-friendly food packaging materials. . Therefore, the most important technologies in the development of single-material packaging materials that replace aluminum foil and aluminum-deposited PET film are key materials such as coating and deposition that provide the barrier properties necessary to secure the shelf life of the contents, and barrier film implementation technology. Domestic technology in Korea is very minimal. Accordingly, Korean Patent Publication No. 10-2073120 provides a multilayer film to solve the problem of impossible recycling due to aluminum foil, but recycling is still difficult because it still contains a metal deposition film.

Korean Patent Publication No. 10-2073120

The purpose of one aspect of the present invention is to provide a single material-based packaging material and a manufacturing method thereof that have excellent oxygen and moisture barrier properties and thus have excellent product preservation properties, and can be recycled as recycled raw materials based on a single material.

In one aspect of the present invention, a base layer containing a polyolefin resin; A barrier layer formed on the base layer; a first film layer formed on the barrier layer and containing polyolefin resin; and a heat-resistant layer formed on the first film layer and including a polyester resin binder, wherein the base layer includes an elastomer.

In another aspect, the present invention includes printing a heat-resistant layer containing a polyester resin binder on one side of a first film layer containing a polyolefin resin; and applying a barrier layer to the other side of the first film layer, applying a base layer containing a polyolefin resin to the other side of the barrier layer, and laminating them.

A packaging material based on a single material according to an embodiment of the present invention has excellent oxygen and moisture barrier properties, so product preservation is excellent, and it can be recycled as a recycled raw material based on a single material.

1 to 5 are structural diagrams of packaging materials according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

The embodiments of the present invention disclosed in the text are illustrative only for illustrative purposes, and the embodiments of the present invention may be implemented in various forms and should not be construed as limited to the embodiments described in the text. . The present invention can make various changes and take various forms, and the embodiments are not intended to limit the present invention to the specific disclosed form, but all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. It should be understood as including.

In this specification, when a part “includes” a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

Throughout the specification, similar parts are given the same reference numerals. Throughout the specification, when a part such as a layer, membrane, region, plate, etc. is said to be “on” or “on” another part, this includes not only the case where it is directly on top of the other part, but also the case where there is another part in between. . Throughout the specification, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. Terms are used only to distinguish one component from another.

packaging material

1 is a structural diagram of a packaging material according to an embodiment of the present invention.

In exemplary embodiments of the present invention, a base layer 10 containing a polyolefin resin; A barrier layer 20 formed on the base layer 10; A first film layer 30 formed on the barrier layer 20 and containing polyolefin resin; and a heat-resistant layer 40 formed on the first film layer 30 and including a polyester resin binder, wherein the base layer 10 includes an elastomer.

Figure 2 is a structural diagram of a packaging material according to an embodiment of the present invention.

In one embodiment, a second film layer 50 containing polyolefin resin is further formed between the barrier layer 20 and the first film layer 30.

“Packing” refers to materials used in packaging food and beverages, agricultural, fishery and livestock products, detergents and cosmetics. In one embodiment, the packaging material may be a flexible packaging material. The above “flexible packaging” refers to a packaging material constructed in the form of a composite multi-layer using flexible films such as paper, plastic, aluminum, and fiber.

Packaging materials according to the prior art generally included aluminum films or were composed of different materials. In the case of packaging materials based on these heterogeneous materials, recycling of the material is difficult due to equipment load during extrusion under high temperature and high pressure conditions, and there is a problem that the physical properties of the manufactured recycled product may be insufficient or the recycling yield may be reduced.

Accordingly, the present inventors completed the present invention by discovering that packaging materials based on a single material are easy to manufacture recycled resin and have the advantage of securing improved yield.

base layer

In one embodiment, the base layer, also called a sealant layer, is a layer that is sealed (heat-sealed) by heat after packaging the product to be packaged (cosmetics, food, etc.) to provide sealing properties. The base layer melts easily at low temperatures and processing is improved, allowing easy sealing after packaging the product to be packaged.

In one embodiment, the polyolefin resin included in the base layer is one selected from the group consisting of polypropylene, low-density polyethylene, linear low-density polyethylene, very low-density polyethylene, medium-density polyethylene, high-density polyethylene, polybutene, and ethylene/propylene copolymer. .

The base layer has a triple structure of a lower layer, a middle layer, and an upper layer. The top layer is formed between the middle layer and the barrier layer. The upper layer is mainly made of polyolefin homopolymer. The upper layer can be formed by mixing a random copolymer with the main raw material. The same raw material may be used for the middle layer and upper layer. The lower layer, which is in contact with the product to be packaged, includes random polyolefin. The random polyolefin means that impact strength and flexibility are enhanced compared to a homopolymer by adding a small amount (2 to 9%) of ethylene during polyolefin polymerization. The melting point (Tm) of the random polyolefin of the lower layer may be 125°C to 140°C. In the base layer, the thickness ratio of the lower layer, middle layer, and upper layer may be 15% to 30%: 40% to 70%: 15% to 30%.

In one embodiment, the elastomer is included in the lower layer of the base layer. The elastomer is at least one selected from the group consisting of polystyrene-based elastomer, polyolefin-based elastomer, polyvinyl chloride-based elastomer, polyurethane-based elastomer, polyester-based elastomer, and polyamide-based elastomer.

The elastomer component improves low-temperature sealing properties, low-temperature impact resistance, and physical properties of the base layer. If the content of the elastomer is excessive, low-temperature sealing properties are improved, but slip properties are reduced, and blocking may occur after fabric lamination and aging. Therefore, it must be contained in an appropriate amount or supplemented with additives. Examples of the additives include slip agents, anti-blocking agents, antioxidants, and silicone oil. Based on the total weight of the lower layer, the slip agent may be included in a small amount of about 200 PPM to 400 PPM, and in addition to the polyolefin resin raw material, the elastomer may be added in an amount of 20% to 50% by weight, and total additives may be added in an amount of 1% to 10% by weight. You can.

The elastomer may be a propylene-based resin randomly containing about 10% ethylene. In this case, the density of the elastomer is 0.87 g/cm ³ to 0.90 g/cm ³ . The melt index (MI) is maintained at approximately 3.5 g/10 min to 4 g/10 min (190° C./2.16 kg). The Vicat softening point is about 70°C, which makes low-temperature sealing possible, considering that the softening point of general polypropylene is 140°C to 170°C.

barrier layer

In one embodiment, the barrier layer is formed to provide gas barrier properties (particularly, oxygen barrier properties) to the packaging material to protect the product being packaged from oxidation by oxygen. In addition, the barrier layer has high gas barrier properties, transparency, improved water resistance and solvent resistance, and can have an even surface and constant thickness. In terms of oxygen barrier properties, it exhibits excellent properties below 0.5 cc, and in the case of moisture barrier properties, it is possible to provide barrier properties at the level of 2g to 4g. By applying a liquid as a barrier layer, it is possible to achieve an oxygen and moisture blocking effect, and since the packaging material can maintain transparency, it can be applied as a packaging material that requires confirmation of contents.

Examples of components included in the barrier layer include polyvinyl alcohols such as fully saponified polyvinyl alcohol, partially saponified polyvinyl alcohol, and ethylene copolymerized polyvinyl alcohol, proteins such as casein, soy protein, and synthetic proteins, oxidized starch, and cations. Starches such as converted starch, urea phosphate esterified starch, and hydroxyethyl etherified starch, cellulose derivatives such as carboxymethyl cellulose, hydroxymethyl cellulose, and hydroxyethyl cellulose, polyvinylpyrrolidone, and sodium alginate. You can.

In one embodiment, a cross-linking agent may be further included in the barrier layer. Since the cross-linking agent causes a cross-linking reaction with the water-based resin contained in the barrier layer, the number of bonds (cross-linking points) in the barrier layer increases. That is, the barrier layer has a more dense structure and can exhibit good gas barrier properties. Examples of the cross-linking agent include polyvalent metal salts (copper, zinc, silver, iron, potassium, sodium, zirconium, aluminum, calcium, barium, magnesium, titanium, etc.; carbonate ions, sulfate ions, nitrate ions, phosphate ions, silicic acid, etc. Examples include compounds combining ionic substances such as ions, nitrogen oxides, and boron oxides), amine compounds, amide compounds, aldehyde compounds, and hydroxy acids.

heat resistant layer

In one embodiment, the heat-resistant layer refers to a layer that disperses the transferred heat by applying a heat-resistant coating to the outer surface of the packaging material, which directly receives heat when processing the packaging material. By including the heat-resistant layer, wrinkles that occur in packaging materials due to high heat can be improved. The heat-resistant layer has excellent heat resistance and dimensional stability and can prevent shrinkage and deformation of the packaging material under high heat and high pressure conditions. In this way, by applying a heat-resistant coating agent containing a heat-resistant resin, dimensional instability caused by shrinkage due to heat during packaging material manufacturing can be improved. By including a heat-resistant layer, external cracks or wrinkles that may occur on the exterior due to heat and pressure applied from the outside during packaging material manufacturing can be improved and workability can be improved.

Included in the heat-resistant layer The heat-resistant coating agent serves to buffer high heat applied directly to the film from the outside, and the resin must not melt or be damaged at that temperature. Since it should not interfere with the printing design, it is transparent as it does not contain dyes or pigments, and to realize physical properties at a temperature of 200℃ or higher (1 second), an ester-based resin with a relatively high melting temperature, such as a polyester binder resin, is used. do. In general, coatings exposed to the outside require physical properties such as excellent adhesion to the substrate and wear resistance, and by supplementing the heat resistance properties, problems such as tearing or contamination of the coating surface do not occur even when the coated surface is exposed to the outside. The heat-resistant coating agent includes 40% to 50% by weight of methyl ethyl ketone (CAS 78-93-3), 1 to 5% by weight of isopropyl alcohol (CAS 67-63-0), and ethyl acetate (CAS 141) as main solvents. -78-6) Contains 13% by weight to 23% by weight.

The heat-resistant coating agent includes toluene, methyl isobutyl ketone, acrylic polyol resin, Trimethylolpropane Tricrylate, n-Butyl acetate, 2-ethoxyethyl acetate, benzophenone, butyl methacrylate, methyl methacrylate, hydroxyethyl methacrylate polymer (2-Propenoic acid, 2-methyl-, butyl ester, polymer with 2-hydroxyethyl 2-methyl-2-propenoate and methyl 2-methyl-2-propenoate, CAS 31942-54-8) and 2-ethylhexyl acrylate, butyl methacrylate, hydroxyethyl methacrylate, methacrylic acid, methyl methacrylate polymer (2-Propenoic acid, 2-methyl-, polymer with butyl 2 -methyl-2-propenoate, 2-ethylhexyl 2-propenoate, 2-hydroxyethyl 2-methyl-2-propenoate and methyl 2-methyl-2-propenoate, CAS 64771-95-5) at least one selected from the group consisting of Includes. The polymer resin includes 5% to 12% by weight of ester polymer and methyl methacrylate resin each independently.

The polymer resin is a thermosetting resin that functions as a binder and has high heat resistance, allowing the coating surface to be maintained uniformly even at temperatures above 250°C. To prevent blocking, 1% to 5% by weight of silicon oxide (CAS 7631-86-9) may be included, and additional additives include a defoaming agent (1% to 2% by weight) and a slip agent, and a cellulose resin ( 1% by weight to 5% by weight).

Figure 3 is a structural diagram of a packaging material according to an embodiment of the present invention.

In one embodiment, an adhesive layer 60 is further formed between the base layer 10 and the barrier layer 20, and an ink layer 70 is formed on the adhesive layer 60.

Figure 4 is a structural diagram of a packaging material according to an embodiment of the present invention.

In one embodiment, an adhesive layer 60 is further formed between the first film layer 30 and the second film layer 50, and an ink layer 700 is formed on the adhesive layer 60.

adhesive layer

The adhesive layer is included to maintain adhesion between film layers during the distribution period. A two-component adhesive may be used as the adhesive layer. In general, when using a solvent-type adhesive, thorough management of the solvent remaining after aging is required. However, for food use, both solvent-type and non-solvent type adhesives are suitable as long as they maintain interlayer adhesion between films. . The adhesive can be cured with a curing agent. An isocyanate curing agent is mixed with a polyurethane polymer having a hydroxyl group at a certain ratio of 10:1, and the film is bonded through the reaction between each functional group. At this time, if the ratio of curing agent is low, curing may not occur properly, which may lead to a decrease in physical properties due to residual uncured reactants. The thickness of the adhesive layer is 2 μm to 4 μm. The adhesion strength between film layers is suitable if it is 250 g/15mm or more. The adhesive layer is included in less than 5% by weight of the total weight in order to meet the requirements of single-material packaging materials and obtain optimal quality for recycling.

ink layer

The ink layer is also called a printing layer, and is formed using an ink composition containing pigments and dyes. The thickness of the ink layer is 0.01 μm to 30 μm. Under the above conditions, appearance and visibility are excellent, and defects can be prevented when processing packaging materials. The ink layer may be formed on one or more of the upper and lower surfaces of the barrier layer and the heat-resistant layer using a roto gravure or flexo printing method, but is not limited thereto. The ink layer is included in less than 5% by weight of the total weight in order to meet the requirements of single-material packaging materials and obtain optimal quality for recycling.

film layer

The first film layer is formed below the heat-resistant layer and serves as a substrate on which the heat-resistant layer is coated. Additionally, the first film layer has excellent adhesion to the ink layer and printability.

The second film layer is formed on the barrier layer and serves as a substrate on which the barrier layer is coated.

In one embodiment, the polyolefin resin included in the first film layer and the second film layer is polypropylene, low-density polyethylene, linear low-density polyethylene, very low-density polyethylene, medium-density polyethylene, high-density polyethylene, polybutene, and ethylene/propylene copolymer. It is one selected from the group consisting of polymers.

In one embodiment, the first film layer is a biaxially oriented polyolefin film, and the base layer is a non-oriented polyolefin film.

In one embodiment, the first film layer and the second film layer are biaxially oriented polyolefin films, and the base layer is a non-oriented polyolefin film.

In one embodiment, the first film layer is a biaxially stretched polypropylene film having a melting point (Tm) of 160°C to 180°C and a glass transition temperature (Tg) of 105°C to 120°C, and the base layer has a melting point ( Tm) is 160°C to 180°C and the glass transition temperature (Tg) is 100°C to 115°C, and the glass transition temperature (Tg) of the biaxially oriented polypropylene film is that of the non-oriented polypropylene film. It is higher than the glass transition temperature (Tg).

In one embodiment, the first film layer and the second film layer are biaxially stretched polypropylene films having a melting point (Tm) of 160°C to 180°C and a glass transition temperature (Tg) of 105°C to 120°C, The base layer is an unstretched polypropylene film with a melting point (Tm) of 160°C to 180°C and a glass transition temperature (Tg) of 100°C to 115°C, and the glass transition temperature (Tg) of the biaxially oriented polypropylene film is as follows. It is higher than the glass transition temperature (Tg) of unstretched polypropylene film.

Polypropylene film is divided into unstretched film and stretched film depending on whether it is stretched. Non-stretched films include cast films and inflation films. They have excellent transparency and surface gloss, heat bonding strength, and dimensional stability, and are used as snack packaging and sealing films for retort food packaging. . Oriented film refers to a film stretched in the longitudinal direction and/or width direction during the extrusion and cooling process, and is divided into uniaxially oriented film and biaxially oriented film depending on stretching. The biaxially oriented film is further divided into BOPP film (Bi-Axially Oriented PP Film) and IOPP film (Inflated oriented PP film).

Compared to non-stretched films, these stretched films have mechanical strengths such as tensile strength, tensile modulus, impact strength, tensile rupture strength, and flexural life, as well as properties such as heat resistance, cold resistance, transparency, and gas barrier properties. In addition, this stretched film is located on the upper layer of the packaging material, so it can suppress appearance wrinkles caused by high heat, and maintains strength so that tearing occurs more smoothly when the bag is opened.

In particular, BOPP film is well-received for its mechanical strength, gloss and transparency, excellent chemical resistance, heat resistance, water resistance, and durability. It is a film that is growing rapidly in the packaging industry as demand increases around the world. The BOPP film is largely divided into general use and deposition use, and general use is produced by subdividing it into purposes such as printing, lamination, white pearl, mat, textile packaging, and cigarette packaging, and for deposition use, aluminum vacuum deposition is generally used. Therefore, it is used in fields that require gas barrier properties and water vapor barrier properties. BOPP film is made by extrusion casting PP powder through a T-die to produce a primary unstretched sheet, and then stretching this sheet in the machine direction (MD) and transverse direction (TD) to produce a biaxially stretched PP film. BOPP film can be mixed with various resins or additives to secure various properties depending on the application.

By using BOPP film in particular as a film layer, it is possible to replace aluminum foil, aluminum evaporated PET film, aluminum oxide transparent evaporated PET, and PVDC coated film that are used in general food packaging materials. In general, aluminum foil shows high barrier properties as a metal, but pinholes due to wrinkles can occur, which can cause a decrease in barrier properties. In the case of aluminum oxide deposition, it has excellent barrier properties as well, but is expensive and can be used in microwave oven products, etc. Application is limited. In the case of PVDC coating film, it can only be applied to limited food packaging materials due to the use of chlorine materials that are harmful to the human body, and in the case of deposited CPP, it is difficult to expand its application due to the poor oxygen barrier properties inherent to CPP film.

In the case of biaxially stretched polypropylene film, which exerts a sealing effect inside packaging materials, a film capable of sealing at relatively low temperatures compared to general unstretched PP film was developed and applied. As materials based on a single material are used, packaging materials with a similar melting temperature structure react sensitively to high external heat during bag processing, causing the film base of the outer layer to melt under sealing conditions and heat-sealing the film to the seal bar. Sticking may result in reduced workability and damage. Accordingly, a non-stretched propylene film that can be heat-sealed under significantly lower conditions than general-purpose CPP is applied.

In one embodiment, the packaging material according to the present invention can be accessed in various ways as packaging material for cosmetics (mask packs) and food products. It can be applied to snacks, ramen, seasoned seaweed, coffee pouches, etc., and can also be applied to external packaging materials for bakeries and dairy products as a replacement for transparent deposition and PVDC.

In one embodiment, the thickness of the base layer and the thickness of the first film layer are each independently 20 μm to 50 μm.

In one embodiment, the thickness of the base layer and the first film layer are each independently 20 μm to 50 μm, and the thickness of the second film layer is 15 μm to 30 μm.

When used as a cosmetic packaging material, the thickness of the base layer and the thickness of the first film layer are each independently 30 μm to 50 μm. If the thickness of the base layer exceeds the upper limit, there is a risk that tearing may become difficult due to the occurrence of burrs (a burr phenomenon in which the fabric is processed uncleanly) during tearing. As the thickness of the first film layer increases, the occurrence of wrinkles due to heat applied from the outside during envelope manufacturing can be reduced, and the higher rigidity makes tearing easier. On the other hand, when printing, the printability may be insufficient due to a decrease in ink transferability due to the high film thickness, so the corresponding thickness level is appropriate. When used as a cosmetic packaging material, the thickness of the second film layer is 15 μm to 30 μm. The second film layer does not need to be of high thickness so a corresponding thickness level is suitable.

When used as a food packaging material, the thickness of the base layer and the thickness of the first film layer are each independently 20 μm to 30 μm. As the thickness of the first film layer increases, the packaging material may be severely bent and wrinkled due to the vertical structure of the customer production line when the contents are injected, so the corresponding thickness level is appropriate as there is a greater risk of pinholes. When used as a food packaging material, the thickness of the second film layer is 15 μm to 20 μm. The second film layer does not need to be of high thickness so a corresponding thickness level is suitable.

How to make packaging materials

1 is a structural diagram of a packaging material according to an embodiment of the present invention.

In other exemplary embodiments of the present invention, printing a heat-resistant layer 40 including a polyester resin binder on one side of the first film layer 30 including a polyolefin resin; and applying a barrier layer 20 to the other side of the first film layer 30 and applying a base layer 10 containing a polyolefin resin to the other side of the barrier layer 20, and laminating them; It provides a method of manufacturing the packaging material, including.

Figure 2 is a structural diagram of a packaging material according to an embodiment of the present invention.

In other exemplary embodiments of the present invention, printing a heat-resistant layer 40 including a polyester resin binder on one side of the first film layer 30 including a polyolefin resin; And applying a second film layer 50 containing a polyolefin resin to the other side of the first film layer 30, and applying a barrier layer 20 to the other side of the second film layer 50, It provides a method of manufacturing the packaging material, including the step of applying a base layer 10 containing a polyolefin resin to the other side of the barrier layer 20 and laminating it.

The base layer is also called a sealant layer, and is a layer that is sealed (heat-sealed) by heat after packaging the product to be packaged (cosmetics, food, etc.) to provide sealing properties. The base layer melts easily at low temperatures and processing is improved, allowing easy sealing after packaging the product to be packaged.

In one embodiment, the base layer is an unstretched polyolefin film. Non-stretched polyolefin film can be heat-sealed starting at 120°C, and considering the state of the packaging material, bags can be normally manufactured at 160°C to 170°C and 100 cuts/min in the final pouch manufacturing process. This means that bags can be manufactured at a very low temperature compared to the fusing at around 190°C to 200°C when manufacturing bags with a single material fabric laminated with general non-stretched film using general pouch processing equipment (Totani, Japan). Unlike the standard where working temperature conditions were very narrow due to sensitivity to temperature, it is possible to implement a relatively range of adhesive processing conditions, and by lowering the working temperature, it shows excellent characteristics in terms of wrinkles and other pitch stability.

In addition, in the base layer, elastomer is added to enable low-temperature sealing to the heat-sealable non-stretched propylene film to widen the adhesion range, thereby alleviating potentially sensitive post-processing conditions. Accordingly, the processing performance of packaging materials can be improved by easing relatively sensitive processing conditions.

In the barrier layer, specifically, the barrier layer can be formed by applying a blended compound liquid containing polyolefin polymers to a certain thickness on a polypropylene film substrate using a wet coating method. It is possible to manufacture a barrier coating film using the gravure coating method, and an appropriate coating amount of 1 μm after drying is sufficient. The solvent is based on water and ethanol and is manufactured by maintaining the chamber temperature around 100°C, which is when blocking occurs and water and alcohol can volatilize if drying is not sufficient.

In the heat-resistant layer, the heat-resistant coating agent included in the heat-resistant layer can be printed in the reverse method during gravure printing, so no separate process is added, and the application amount after coating is 170 to 200 lines like a general printing copper plate. It is at the μm level. When the heat-resistant coating agent is used, heat directly transmitted to the film substrate is dispersed in the coating layer, thereby improving fabric shrinkage and wrinkles caused by high heat. Even in a seal bar compression test under a temperature condition of 250℃ for 1 second or more, no tearing of the external ink or substrate, or fabric shrinkage, etc. occurred, and therefore, it remains sturdy even under the conditions of envelope processing under temperature conditions of 190℃ or higher. maintain.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments so that those skilled in the art can easily practice it. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

{Example}

<Manufacture Example 1> Manufacture of packaging material for cosmetics according to Example 1

Reverse printing was performed on the first film layer of the BOPP film to form a heat-resistant layer. An ink layer was applied to the other side of the first film layer, and an adhesive layer was applied by mixing an isocyanate curing agent in a base composition of polyurethane polymer with a hydroxyl group at a certain ratio of 10:1. A coating agent containing raw materials was applied to the other side of the adhesive layer using a wet coating method to form a second film layer of the BOPP film. A barrier layer is applied to the other side of the second film layer by applying a coating agent containing raw materials using a wet coating method, an adhesive layer is applied to the other side of the barrier layer, and a base layer of the non-stretched cast PP (CPP) film is applied. was applied. The multilayer film was laminated to finally prepare a cosmetic packaging material (110 mm × 160 mm) according to Example 1 as shown in Figure 5 (base layer thickness: 50 μm, second film layer thickness: 20 μm, first film layer thickness: 50 μm) ). Figure 5 is a structural diagram of a packaging material according to an embodiment of the present invention.

<Manufacture Example 2> Manufacture of food packaging material according to Example 2

Reverse printing was performed on the first film layer of the BOPP film to form a heat-resistant layer. An ink layer was applied to the other side of the first film layer, and an adhesive layer was applied by mixing an isocyanate curing agent in a base composition of polyurethane polymer with a hydroxyl group at a certain ratio of 10:1. A coating agent containing raw materials was applied to the other side of the adhesive layer using a wet coating method to form a second film layer of the BOPP film. A barrier layer is applied to the other side of the second film layer by applying a coating agent containing raw materials using a wet coating method, an adhesive layer is applied to the other side of the barrier layer, and a base layer of the non-stretched cast PP (CPP) film is applied. was applied. The multilayer film was laminated to finally prepare a food packaging material (230 mm ). Figure 5 is a structural diagram of a packaging material according to an embodiment of the present invention.

<Experimental Example 1> Evaluation of physical properties of cosmetic packaging materials according to Example 1

The physical properties of the cosmetic packaging material according to Example 1 and the food packaging material according to Example 2 were evaluated. Gas barrier rating (OTR) was measured based on ASTM D 3985 standard, and water barrier rating (WVTR) was measured based on ASTM F 1249 standard. The results are shown in Table 1 below.

division Example 1 Example 2 Gas barrier degree (cc/[m ² -day]) 0.5 or less 0.5 or less Moisture barrier (g/[m ² -day]) 1.5~2.2 1.7~2.3

From Table 1, in the case of the cosmetic packaging material according to Example 1 and the food packaging material according to Example 2, the gas barrier degree is 0.5 cc or less, which is the lower limit of measurement, and the moisture barrier degree is at the level of 1 g, and gas barrier properties and moisture It can be seen that the barrier properties are all excellent.

<Experimental Example 2> Evaluation of practicality of cosmetic packaging material according to Example 1

1. Evaluation method

The practicality of the cosmetic packaging material according to Example 1 was evaluated. More specifically, under 45°C oven storage conditions, the weight loss % of the mask pack contents was evaluated for each parking period. After filling the pouch with the contents of the hand mask and storing it, the amount of reduction was evaluated by measuring the amount of reduction in the total weight. For comparison, a commercially available lifting mask packaging material (PET 12 μm/adhesive layer/aluminum 6-7 μm/adhesive layer 2-4 μm/polyethylene 50-80 μm; Company A) was prepared as Comparative Example 1 (approximately 27 g filled). The results are shown in Table 2 below.

division Example 1 Comparative Example 1 4th week reduction rate (wt%) -0.9 -One 12th week reduction rate (wt%) -1.4 -3

From Table 2, it can be seen that the cosmetic packaging material according to Example 1 meets the quality standards for cosmetic packaging materials. Meanwhile, in the case of Comparative Example 1, it can be expected that the quality will deteriorate as the amount of content decreases and the internal viscosity of the pouch increases.

<Experimental Example 3> Evaluation of practicality of food packaging materials according to Example 2 1

1. Evaluation method

The practicality of the food packaging material according to Example 2 was evaluated. More specifically, under storage conditions of 40°C and 90RH, the amount of moisture increase in food contents by parking was evaluated. After filling the pouch with the contents of the fried snack and storing it, the amount of decrease was evaluated by measuring the increase in total weight. For comparison, commercially available fried snack packaging materials (stretched polypropylene 20 μm/polyethylene 10-20 μm/aluminum-deposited PET 12 μm/polyethylene 10-20 μm/non-stretched polypropylene 20-30 μm; Nongshim) were prepared as Comparative Example 2 (about 96 g) charge). The results are shown in Table 3 below.

division Example 2 Comparative Example 2 8th week increase rate (wt%) +2.76 +3

From Table 3, it can be seen that the edible packaging material according to Example 2 meets the quality standards for food packaging materials. Meanwhile, in the case of Comparative Example 2, it can be expected that moisture will infiltrate and cause texture deterioration in the food.

<Experimental Example 4> Evaluation of practicality of food packaging materials according to Example 2 2

1. Evaluation method

The food packaging material according to Example 2 was evaluated for practicality in the same manner as in Experimental Example 3. For comparison, the packaging material of Comparative Example 2 was prepared. The results are shown in Table 4 below.

division Example 2 Comparative Example 2 1st week weight (g) 96.21 96.21 2nd week weight (g) 96.75 96.44 3rd week weight (g) 96.8 97.85 Week 4 Weight (g) 97.1 97.93 Week 5 Weight (g) 97.29 98.31 Week 6 Weight (g) 97.38 99.01 7th week weight (g) 97.38 99.13 8th week weight (g) 97.55 99.20

From Table 4, it can be seen that the edible packaging material according to Example 2 had excellent moisture barrier properties and excellent product preservation properties. In addition, in the case of the edible packaging material according to Example 2, compared to the packaging material of the current specification made of composite materials, it can be recycled as a recycled raw material based on a single material. In the above, exemplary embodiments of the present invention are the above-mentioned preferred embodiments. Although it has been described in relation to examples, various modifications and variations can be made without departing from the gist and scope of the invention. Accordingly, the appended claims will include such modifications and variations as long as they fall within the spirit of the present invention.

10: base layer 20: barrier layer
30: first film layer 40: heat-resistant layer
50: second film layer 60: adhesive layer
70: ink layer

Claims (5)

A base layer containing polyolefin resin;
A barrier layer formed on the base layer and containing a polyolefin-based polymer;
a second film layer formed on the barrier layer and containing polyolefin resin, but not containing metal or metal oxide;
a first film layer formed on the second film layer and containing polyolefin resin, but not containing metal or metal oxide; and
It includes a heat-resistant layer formed on the first film layer and including a polyester resin binder,
The base layer includes an elastomer,
An adhesive layer is further formed between the first film layer and the second film layer,
An ink layer is formed on the adhesive layer,
The first film layer and the second film layer are biaxially stretched polyolefin films,
A packaging material wherein the base layer is an unstretched polyolefin film. According to paragraph 1,
An adhesive layer is further formed between the base layer and the barrier layer,
A packaging material in which an ink layer is formed on the adhesive layer. According to paragraph 1,
The first film layer and the second film layer are biaxially stretched polypropylene films having a melting point (Tm) of 160°C to 180°C and a glass transition temperature (Tg) of 105°C to 120°C,
The base layer is an unstretched polypropylene film with a melting point (Tm) of 160°C to 180°C and a glass transition temperature (Tg) of 100°C to 115°C,
A packaging material wherein the glass transition temperature (Tg) of the biaxially stretched polypropylene film is higher than the glass transition temperature (Tg) of the non-stretched polypropylene film. According to paragraph 1,
The thickness of the base layer and the thickness of the first film layer are each independently 20 μm to 50 μm,
A packaging material wherein the second film layer has a thickness of 15 μm to 30 μm. Printing a heat-resistant layer containing a polyester resin binder on one side of a first film layer containing a polyolefin resin; and
A second film layer containing a polyolefin resin is applied to the other side of the first film layer, a barrier layer is applied to the other side of the second film layer, and a substrate containing a polyolefin resin is applied to the other side of the barrier layer. The method of manufacturing a packaging material according to any one of claims 1 to 4, comprising the step of applying a layer and laminating it.