KR102101321B1 - Eco-friendly coffee packaging multilayer film with excellent oxygen barrier and composting - Google Patents

Abstract

The present invention relates to an eco-friendly coffee packaging multilayer film having excellent oxygen barrier properties and composting, and more specifically, polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate , Polyhydroxybutyrate (PHB), poly-3-hydroxyvalerate (PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate- Poly-3- (3-hydroxybutyrate-co-3-hydroxyvalerate), poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (poly- (3-hydroxybutyrate-co- 3-hydroxyhexanoate) selected from the group consisting of one or more biodegradable resins and polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) 50 to 70% by weight: 50 to 30% by weight By weight ratio of It is composed of a base film layer formed of an organic-inorganic hybrid resin in which nano montmorillonite is dispersed in a mixed resin composition, and an oxygen barrier coating layer coated on an upper surface of the base film layer; and excellent oxygen barrier properties. It is related to a multi-layered film for eco-friendly coffee packaging with compostability and excellent mechanical strength while being biodegradable.

Description

Eco-friendly coffee packaging multilayer film with excellent oxygen barrier and composting}

The present invention relates to an eco-friendly coffee packaging multilayer film having excellent oxygen barrier properties and composting, and more specifically, polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate , Polyhydroxybutyrate (PHB), poly-3-hydroxyvalerate (PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate- Poly-3- (3-hydroxybutyrate-co-3-hydroxyvalerate), poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (poly- (3-hydroxybutyrate-co- 3-hydroxyhexanoate) selected from the group consisting of at least one biodegradable resin and polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) 50 to 70% by weight: 50 to 30% by weight By weight ratio of It is composed of a base film layer formed of an organic-inorganic hybrid resin in which nano montmorillonite is dispersed in a mixed resin composition, and an oxygen barrier coating layer coated on an upper surface of the base film layer; and excellent oxygen barrier properties. It relates to a multi-layered film for eco-friendly coffee packaging with compostability and excellent mechanical strength, while being biodegradable.

In general, coffee is widely distributed in two types: raw beans that have not undergone a roasting process and raw beans that have undergone a roasting process. In the case of raw coffee, the shelf life is usually about two years, but the disadvantage is that it must be consumed after grinding through a direct roasting process. On the other hand, when roasting, the flavor is blown away quickly, so the expiration date is greatly reduced depending on the packaging method, decreasing from 1 month to 5 months.

In addition, since coffee has a fixed production location and is delivered worldwide, when the distribution process of roasting coffee is long, the original aroma decreases, so in recent years how to roast raw coffee or roast it at home to feel the fresh aroma of coffee. As this demand is gradually generalized and the demand for high-quality coffee increases, a packaging method is required to maintain its aroma and taste to the maximum. In the case of green beans, it is necessary to maintain about 12% moisture to maintain the highest quality. Do.

Accordingly, the packaging method according to the shape of the coffee also changes. Coffee in the form of green beans is packaged and distributed in the form of jute sack, grain pro bag, and pouch, and products in the form of beans and ground are distributed in the form of pouch, can, and roasting Depending on the presence or absence of the process, the packaging type changes greatly. When the roasting process, the gas such as CO2 may be released from the coffee and burst into the packaging. Since there is no gas generation in the storage state, a packaging material without a gas control device is used.

On the other hand, the quality of green beans shows the most ideal condition when the moisture is kept at about 12%, and the jute sack, grain bag, and pouch, which are packaging forms of green beans, have different environmental factors to manage in the distribution process. In the case of the jute sack, the focus is on breathability, and the grain bag is used universally for the convenience of distribution. In the case of the pouch, it is a packaging that focuses on blocking and sales.

In particular, jute sacks and grain probags are mainly used for the wholesale and export of large quantities of coffee beans, but the packaging for sale to the consumer has poor marketability, and the most frequently encountered packaging, the pouch-type packaging, is sold to consumers. It has excellent moisture and oxygen barrier properties by using aluminum bonding on the inside of the packaging (paper) in the form of packaging with an emphasis on. However, because it is difficult to recycle through aluminum bonding, it adversely affects the environment during disposal and disposal.

Therefore, after using consumables packaging such as coffee, most of the packaged wastes are classified as household wastes, and some of these wastes have a harmful effect on the environment.The regulations on hazardous wastes in the related regulations list the hazardous properties in Annex 3 of the Basel Convention It can be found in the list. Among them, in addition to reactivity, combustibility, corrosiveness, and toxicity, infectivity is included, and domestic laws and regulations include 599 general pollutants and 294 species across 8 laws including the Water Quality Conservation Act, the Air Quality Conservation Act, and the Soil Environment Conservation Act. Certain hazardous substances are listed. In developed countries such as Europe, heavy metals contained in packaging materials are being set and operated for the protection and recyclability of their products, but there is no such regulation in Korea, so environmental pollution caused by packaging waste is serious.

As described above, an eco-friendly biodegradable high barrier packaging material that can replace the existing aluminum bonding packaging has been recently developed to reduce the impact of coffee packaging on the environment. Looking at the conventional eco-friendly biodegradable high barrier packaging material, Korean Patent Registration No. 10-1045869 (2011) On June 27), a substrate layer containing a crystalline polylactic acid polymer, a first resin layer formed on one surface of the substrate layer and containing a polylactic acid polymer having a D-lactic acid content of 4% by weight or more, and the substrate It has a configuration comprising a second resin layer formed on the other side of the layer and containing a homopolymer or copolymer of an aliphatic or aromatic polyester, the content of the polylactic acid-based polymer to the entire film is 50 to 99% by weight, A multi-layered biodegradable polyester film having a thermal adhesive strength of at least 500 gf / inch of at least one of the first resin layer and the second resin layer is provided. It is.

However, the multi-layered biodegradable polyester film uses biodegradable resins such as polylactic acid and polyglycolic acid, but the barrier properties of gas and moisture are insufficient, so that the second resin layer has aluminum oxide, silicon oxide, and alumina oxide. There was a problem that the back should be used in a deposited form.

In addition, a first resin layer made of polyvinyl alcohol (PVOH) having a melting temperature (Tm) of 170 to 220 ° C in Korean Patent Registration No. 10-1156600 (June 08, 2012); And a second resin layer located on both sides of the first resin layer and made of polylactic acid (PLA) or polyethylene terephthalate (PET) having a melting temperature of 205 ° C. or lower, a multilayer barrier film is known, but the patent is Since there is a second resin layer made of polyethylene terephthalate (PET), there is a problem that it is impossible to completely biodegrade.

In addition, in Korean Patent Registration No. 10-1775070 (August 30, 2017), a first resin layer containing an aliphatic polycarbonate resin and a second resin layer containing an aliphatic polyester resin are alternately stacked in three or more layers. In the biodegradable barrier film having a structure, the biodegradable barrier film has a layered structure of 43 to 145 layers, and the biodegradable barrier film has an oxygen permeability of 800 cc / m2 · day · atm or less at 0% relative humidity. A biodegradable barrier film is known, having a moisture permeability of 400 g / m2 · day · atm or less at 38 ° C. and 100% relative humidity.

In addition, in the Korean Patent Publication No. 10-2015-0082355 (July 15, 2015) (i) the innermost layer of the mixture containing 20 to 95% by weight of the first polylactide and 5 to 80% by weight of another biodegradable polymer , (ii) an intermediate layer containing a second polylactide, and (iii) an outermost layer of a mixture comprising 20 to 95% by weight of the third polylactide and 5 to 80% by weight of another biodegradable polymer. A method for producing a biodegradable packaging material comprising coextruding a coating on a fiber substrate, wherein the second polylactide has a lower melt index than the first and third polylactide melt indexes. Methods of manufacturing packaging materials are known.

However, the Korean Patent Registration No. 10-1775070 and Korean Patent Publication No. 10-2015-0082355 show a satisfactory gas barrier property when the biodegradable polymer layer is stacked in three or more layers, and thus are difficult to manufacture and have a thickness as they are stacked in three or more layers. There was a thickening problem.

Korean Registered Patent 10-1045869 (June 27, 2011) Korean Registered Patent 10-1156600 (June 8, 2012) Korean Registered Patent 10-1775070 (August 30, 2017) Korean Patent Publication No. 10-2015-0082355 (July 15, 2015)

The present invention to solve the above problems, polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate (PHB), poly-3- Hydroxy valerate (poly-3-hydroxyvalerate, PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxy valerate (poly- (3-hydroxybutyrate) -Co-3-hydroxyvalerate), at least one biodegradable selected from the group consisting of poly- (3-hydroxybutyrate-co-3-hydroxyhexanoate) Resin and polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) are mixed with 50 to 70% by weight: 50 to 30% by weight. Organic / Inorganic Hybrid Consisting of a base film layer formed of a resin and an oxygen barrier coating layer coated on the upper surface of the base film layer, while having excellent oxygen barrier properties, it is biodegradable and compostable and has excellent mechanical strength. It is an object to solve the problem of providing a multi-layer film for eco-friendly coffee packaging.

The present invention is to solve the above problems, polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate (PHB), poly-3- Hydroxy valerate (poly-3-hydroxyvalerate, PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxy valerate (poly- (3-hydroxybutyrate) -Co-3-hydroxyvalerate), at least one biodegradable selected from the group consisting of poly- (3-hydroxybutyrate-co-3-hydroxyhexanoate) Resin and polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) are mixed with 50 to 70% by weight: 50 to 30% by weight. Organic / Inorganic Hybrid Consisting of a base film layer formed of a resin and an oxygen barrier coating layer coated on the upper surface of the base film layer, while having excellent oxygen barrier properties, it is biodegradable and compostable and has excellent mechanical strength. The environment-friendly multi-layer film for coffee packaging is used as a solution to the problem.

The oxygen barrier coating layer is colloidal silica; Distilled water; ethanol; PH adjusting agent selected from nitric acid or ammonia water; Vinyl trichlorosilane, vinyl tri (2-methoxyethoxy) silane, vinyl triethoxysilane, vinyl trimethoxysilane, vinyl silane, 3-methacryloxypropyl trimethoxysilane, 2- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3 -Aminopropyl methyl dimethoxysilane, 3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3-chloropropyl trimethoxysilane One or more silane coupling agents; Wetting agents; Leveling agent; to be formed by coating, cured with a coating solution that is formulated to form a solution to the problem.

The eco-friendly coffee packaging multi-layer film is an oxygen permeability of 2cc / ㎡, day, atm (100um film) or less according to ASTM D 3985 as a solution to the problem.

The eco-friendly coffee packaging multi-layer film has a tensile strength of 25Mpa or more and an elongation of 50% or more according to ASTM D 638 as a solution to the problem.

Eco-friendly coffee packaging multilayer film excellent in oxygen barrier properties and compostable according to the present invention is polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate ( polyhydroxybutyrate (PHB), poly-3-hydroxyvalerate (PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxy Consisting of poly- (3-hydroxybutyrate-co-3-hydroxyvalerate), poly-3-hydroxybutyrate-co-3-hydroxyhexanoate Mixing composition of at least one biodegradable resin selected from the group and polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) in a weight ratio of 50 to 70% by weight: 50 to 30% by weight In mixed resin Consists of a base film layer formed of an organic-inorganic hybrid resin in which no montmorillonite is dispersed; and an oxygen barrier coating layer coated on the upper surface of the base film layer. It is biodegradable while having excellent oxygen barrier properties. Composting is possible and the mechanical strength is excellent.

The present invention, polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate (polyhydroxybutyrate, PHB), poly-3-hydroxy valerate (poly -3-hydroxyvalerate (PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxyvalerate (poly- (3-hydroxybutyrate-co-3-hydroxyvalerate) ), Poly-3-hydroxybutyrate-co-3-hydroxyhexanoate and at least one biodegradable resin selected from the group consisting of poly- (3-hydroxybutyrate-co-3-hydroxyhexanoate) and polybutylene ad Fate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) is formed of an organic / inorganic hybrid resin in which nano montmorillonite is dispersed in a mixed resin composed of 50 to 70% by weight: 50 to 30% by weight Base film And; an oxygen barrier coating layer coated on the upper surface of the base film layer; including an excellent oxygen barrier property while being biodegradable to enable composting and excellent eco-friendly coffee packaging multilayer film with excellent mechanical strength It is characterized by configuration.

The oxygen barrier coating layer is colloidal silica; Distilled water; ethanol; PH adjusting agent selected from nitric acid or ammonia water; Vinyl trichlorosilane, vinyl tri (2-methoxyethoxy) silane, vinyl triethoxysilane, vinyl trimethoxysilane, vinyl silane, 3-methacryloxypropyl trimethoxysilane, 2- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3 -Aminopropyl methyl dimethoxysilane, 3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3-chloropropyl trimethoxysilane One or more silane coupling agents; Wetting agents; Leveling agent; characterized by the technical composition that is formed by coating and curing with a coating solution that is composed.

The eco-friendly coffee packaging multi-layer film is characterized by the technical composition that the oxygen permeability according to ASTM D 3985 is 2 cc / m 2, day, atm (100 um film) or less.

The eco-friendly coffee packaging multi-layer film is characterized by the technical composition that the tensile strength according to ASTM D 638 is 25 Mpa or more and the elongation is 50% or more.

Hereinafter will be described in detail through embodiments and drawings of the present invention so that those skilled in the art to which the present invention pertains can easily practice. However, the present invention may be implemented in various different forms, and is not limited to the embodiments and drawings described herein.

First, the environment-friendly coffee packaging multilayer film having excellent oxygen barrier properties and composting of the present invention is polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate (polyhydroxybutyrate, PHB), poly-3-hydroxyvalerate (PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxy With poly- (3-hydroxybutyrate-co-3-hydroxyvalerate), poly-3-hydroxybutyrate-co-3-hydroxyhexanoate At least one biodegradable resin selected from the group consisting of polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC) is mixed in a weight ratio of 50 to 70% by weight: 50 to 30% by weight To the mixed resin No montmorillonite which is formed of the organic-inorganic hybrid resin dispersion base film layer; consists including; oxygen barrier (barrier) coating layer coated on the upper surface of the base film layer.

Here, the biodegradable resin means a resin that can be decomposed in a natural aerobic (composting) and anaerobic (embedded) environment, and the biodegradation of the resin is a compound that can assimilate the resin or a material that is less harmful to the environment, such as humus. It happens when you metabolize. In particular, the biodegradable resins can be biodegradable because of ester bonds that can be hydrolyzed as aliphatic polyesters.

Polylactic acid (PLA) is typically used among the biodegradable resins, but the polylactic acid-based film is environmentally friendly, but is susceptible to moisture or moisture and has high oxygen permeability, so that it is separately treated (for example, when used for packaging). Metal deposition, lamination with other films, etc.) is required.

Accordingly, polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate (PEC), which is resistant to moisture and moisture and has excellent oxygen barrier properties, is 50 to 70% by weight with the biodegradable resin: 50 to 30% by weight. Mixing at a weight ratio of%, and dispersing nano montmorillonite to form an organic-inorganic hybrid resin formed by a sol-gel process as a base film layer is a core configuration of the present invention.

At this time, if it exceeds the weight ratio range, there is a disadvantage that does not exhibit satisfactory physical properties in oxygen barrier properties and biodegradability (composting), in particular, the polybutylene adipate-co-butylene terephthalate (PBAT) or polyethylene carbonate ( When the content of PEC) exceeds 50% by weight, biodegradability decreases, and when it is less than 30% by weight, oxygen barrier property decreases, and preferably, the polybutylene adipate-co-butylene terephthalate (PBAT) ) Or when the content of polyethylene carbonate (PEC) is 40 to 50% by weight, it has excellent oxygen permeability and degradability.

On the other hand, the organic-inorganic hybrid resin means to disperse inorganic nanoparticles, etc. in a polymer, thereby producing a structurally uniform composite material, and these composite materials maintain the flexibility and excellent processability of the organic polymer, and are excellent in inorganic nanomaterials. It is in the spotlight as an excellent material by adding mechanical strength and thermal stability. In particular, in the present invention, oxygen barrier property is not lowered, and high heat resistance and mechanical strength are exhibited.

Inorganic nanoparticles used in the organic-inorganic hybrid resin are nano montmorillonite.

The montmorillonite (Montmorillonite) (hereinafter, MMT) is As a clay, it is abundant in nature and is a very useful material from an economic point of view, and has been applied to various uses because it imparts excellent mechanical and chemical resistance.

Particularly, green clay (Smectite Clay) is most commonly used to make nanoparticles suitable for nanocomposite manufacturing because it can improve the physical properties by adding a small amount compared to the conventional composite material having a dispersed phase size of ㎜ or ㎚. Is used.

Among the materials used in polymers, nanocomposite materials that have been studied recently are generally used as nano-sized inorganic particles as reinforcing materials to show superior mechanical properties and chemical resistance in a smaller amount than conventional reinforcing agents by increasing the bonding surface area. Among them, research on polymer nanocomposites using MMT is currently being extended to the overall polymer area from the method of inserting low molecular weight monomers between layers.

In the early stages of the research on polymer composite materials using MMT, in-situ polymerization was the main research field, but recently, the research area has expanded to thermoset polymers, thermoplastic polymers and rubbers, and the production of polymer / MMT composite materials There are many ways to do this, but the melting and blending method has been attracting much attention in recent years for economic reasons.

In addition, the MMT refers to a very soft foliar silicate mineral formed when an aqueous solution having fine crystals known as clay precipitates, and MMT is a layered inorganic material obtained naturally or purified or artificially synthesized. , Platelets with a thickness of 1 ~ 3nm form a layered structure with ion bonding force or van der Walls attraction. The dispersion of MMT with layered structure depends on the affinity between the polymer and the clay, the manufacturing method, and the degree of organication of the clay. Accordingly, it can be divided into two types: an insertable nanocomposite and a peelable nanocomposite.

The inserted nanocomposite is formed when the MMT layers are separated by a fixed amount, and each layer serves as a reinforcement material for the polymer, and the exfoliated nanocomposite is that each layer of the MMT is randomly separated or oriented and dispersed within the polymer. It is formed when there is, and each layer of MMT is sufficiently separated and irregularly aligned to achieve complete interfacial adhesion, and as a result, it provides strength sufficient to improve various properties of the nanocomposite.

In particular, the dispersion of the MMT layer increases the motion and melt viscosity of the polymer chain, and increases the gas and moisture barrier properties of the polymer by lengthening the path of the material through which the MMT individual layer moves, in addition to the polymer / MMT nanocomposite It has the characteristics of improving mechanical strength, flame retardancy, abrasion resistance, and heat resistance.

On the other hand, the oxygen barrier (barrier) coating layer of the present invention is a colloidal silica; Distilled water; ethanol; PH adjusting agent selected from nitric acid or ammonia water; Vinyl trichlorosilane, vinyl tri (2-methoxyethoxy) silane, vinyl triethoxysilane, vinyl trimethoxysilane, vinyl silane, 3-methacryloxypropyl trimethoxysilane, 2- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3 -Aminopropyl methyl dimethoxysilane, 3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3-chloropropyl trimethoxysilane One or more silane coupling agents; Wetting agents; Leveling agent; It is formed by coating and curing with a coating solution composed of.

Looking at the manufacturing process of the coating solution for forming the oxygen barrier (barrier) coating layer, colloidal silica as a silica precursor as a hydrolysis solvent, distilled water and ethanol and vinyl trichlorosilane, vinyl tri (2-methoxyethoxy) silane, Vinyl triethoxysilane, vinyl trimethoxysilane, vinylsilane, 3-methacryloxypropyl trimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl trimethoxysilane, 3-glycidyloxypropyl Methyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, A silane mixture is formed by adding one or more silane coupling agents selected from N-phenyl-3-aminopropyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, and 3-chloropropyl trimethoxysilane, wherein From nitric acid or ammonia water Adding a pH adjusting agent and a hydrolytic catalyst to be and, by adding a wetting agent and a leveling agent is prepared and stirred homogeneously.

Colloidal silica (CS) of nanoparticles stably dispersed in distilled water and ethanol is capable of synthesizing an organic-inorganic hybrid composite material close to glass by sol-gel reaction with the trivalent or tetravalent alkoxy silanes listed above. Do. These composite materials are excellent in the hardness, weather resistance, thick film coating properties, heat resistance, etc. of the coating film and can be used as a coating agent or binder material for surface modification and protection.

In particular, the coating solution for forming the oxygen barrier coating layer improves gas barrier properties by densifying the non-degradable portion of the biodegradable resin of the base film layer and the pores on the resin surface.

In addition, the eco-friendly coffee packaging multilayer film of the present invention has an oxygen permeability of 2 cc / m 2, day, atm (100 μm film) or less according to ASTM D 3985, a tensile strength of 25 Mpa or more, and an elongation of 50% or more according to ASTM D 638. Shows.

[Production of eco-friendly coffee packaging multilayer film of the present invention]

After drying the polylactic acid resin (Nature Works LLC, 4032D) and polyethylene carbonate (PEC) with a hot air dryer at 110 ° C for 3 hours to remove moisture, homogenize by mixing at a weight ratio of 60% by weight: 40% by weight, and nano montmorillonite And homogeneously dispersed and mixed to prepare an organic-inorganic hybrid resin, and then melt-extruded with an extruder having a temperature of 220 ° C. to form a base film layer.

Colloidal silica (SS-Sol 30E, S-CHEMTECH Co.) and distilled water and ethanol (EtOH, 99.5%, Samchun Chemical) were mixed in a weight ratio of 1: 1: 1 (30 g: 30 g: 30 g), and 3- After adding methacryloxypropyl trimethoxysilane, the mixed solution was stirred for 1 hr. Then, ammonia water (28%, Samchun Chemical) was added to adjust the pH of the solution, followed by addition of a hydrolysis catalyst, followed by homogeneous stirring by adding a wetting agent and a leveling agent to prepare a coating solution, and then the first base film. The layer was coated and cured to form an oxygen barrier coating layer.

[Comparative Example 1]

In [Example 1], the same as [Example 1], except that the base film layer is formed of PLA alone instead of the organic-non-hybrid resin, and the oxygen barrier coating layer is formed of an ethylene vinyl alcohol (EVOH) resin coating solution. Multilayer film was prepared.

After performing physical properties measurement and performance evaluation for the multilayer film prepared according to the above [Example 1] and [Comparative Example 1] in the following manner, the results are shown in [Table 1].

(1) Oxygen permeability

Oxygen permeability (cc / m2 · day · atm) at 0% relative humidity was measured using an air permeability meter (OX-TRAM 2/21, MOCON, USA) according to the standard measurement method of ASTM D3985.

(2) Tensile strength and elongation

Tensile properties were recorded at a yield point (Y) by measuring tensile properties on a 32 mm Type I bar at a crosshead speed of 5 mm / min at 23 ° C., according to the standard measurement method of ASTM D638. Percent elongation (tensile elongation) was recorded at break point (B).

(3) Biodegradation rate

The ratio of the biodegradability value measured by KS M3100-1 (2003) for 180 days to a standard substance was calculated according to Equation 1 below.

[Equation 1]

Biodegradation rate (%) = (Biodegradability of sample) / (Biodegradability of standard substance) × 100

Oxygen permeability
(cc / m2 · day · atm) The tensile strength
(MPa) Elongation
(%) Biodegradation rate
(%) Example 1 1.8 30 64 60 Comparative Example 1 210 25 72 80

As shown in [Table 1], it can be seen that the multi-layered eco-friendly coffee packaging multilayer film having excellent oxygen barrier properties and compostability of the present invention has excellent oxygen permeability and tensile strength.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and variations without departing from the essential characteristics of the present invention. Therefore, the embodiments and drawings disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain them, and the scope of the technical spirit of the present invention is not limited by the embodiments and the drawings. The scope of protection of the present invention should be interpreted by the claims below, and all technical spirits within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims (4)

Polylactic acid (PLA), polycaprolactone, polyglycolic acid, polybutylene succinate, polybutylene adipate, polyhydroxybutyrate (PHB), poly-3-hydroxyvalerate , PBV), polyhydroxybutyrate valerate (PHBV), poly-3-hydroxybutyrate-co-3-hydroxyvalerate, poly- At least one biodegradable resin selected from the group consisting of 3-hydroxybutyrate-co-3-hydroxyhexanoate and polybutylene adipate-co- Base film layer formed of organic / inorganic hybrid resin in which nano montmorillonite is dispersed in a mixed resin composed of 50 to 70% by weight of 50 to 30% by weight of butylene terephthalate (PBAT) or polyethylene carbonate (PEC) And; Comprising: a; oxygen barrier (barrier) coating layer coated on the upper surface film device layer
The oxygen barrier coating layer is colloidal silica; Distilled water; ethanol; PH adjusting agent selected from nitric acid or ammonia water; Vinyl trichlorosilane, vinyl tri (2-methoxyethoxy) silane, vinyl triethoxysilane, vinyl trimethoxysilane, vinyl silane, 3-methacryloxypropyl trimethoxysilane, 2- (3,4- Epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3 -Aminopropyl methyl dimethoxysilane, 3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3-chloropropyl trimethoxysilane One or more silane coupling agents; Wetting agents; Leveling agent; Eco-friendly multi-layer packaging film for coffee, characterized in that it can be composted by being biodegradable while being coated and cured with a coating solution that is formulated to have excellent oxygen barrier properties.
delete According to claim 1,
The eco-friendly coffee packaging multi-layer film is an eco-friendly coffee packaging multi-layer film, characterized in that the oxygen permeability according to ASTM D 3985 is less than 2cc / ㎡, day, atm (100um film).
According to claim 1,
The eco-friendly coffee packaging multilayer film is an eco-friendly coffee packaging multilayer film characterized in that the tensile strength according to ASTM D 638 is more than 25Mpa and the elongation is more than 50%.