KR101970002B1 - Film for food packaging and method for manufacturing same - Google Patents

Abstract

The present invention relates to a film for a food packaging material, which effectively prevents the decomposition of food, and a manufacturing method thereof. The film for a food packaging material comprises: a first substrate; a second substrate; and a blocking layer disposed between the first and second substrates, and including a natural substance.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a film for food packaging materials,

The present invention relates to a film for food packaging materials and a method for producing the same.

The present invention relates to the development of environmentally friendly coatings based on natural materials and development of multi-layer barrier films for foods using this technology in the research project on high-value-added food technology in the National R & D Project, Ministry of Agriculture, Forestry and Fisheries, 315070-3, 2015.10.12. ~ 2018.10.11.). In addition, the present invention is a research project of "Adhesive for environmentally friendly high-grade food packaging material applying nano-clay and development of packaging film using the nano-clay" of the technical support department of the National Food Cluster Support Center (Research Period 2017.10.27 ~ October 26, 2018).

A variety of food packaging materials have been used extensively in retort food, lunch boxes, ramen noodles, instant rice, etc. in modern life. It is important that these food packaging materials, especially those with moisture and air tightness, maintain the food's lead for a long time.

Conventionally used food packaging materials include metal, glass, paper, and plastic. Among them, metal foil such as aluminum foil, processed paper, and various plastic film products are used in the form of film.

Metal packaging materials have high mechanical strength and high barrier properties against external environments such as moisture, oxygen, and ultraviolet rays. However, it is heavy compared to plastic, and when it comes into contact with acidic food, it may be rusty and it may be difficult to store for long time. Paper packaging materials are relatively easy to process, are rich in raw materials, are cheap, and can be recycled. However, paper packaging is excellent in environmental friendliness, but it is limited in the kind of food that can be wrapped in moisture.

Plastic packaging materials are generally lightweight, excellent in transparency, and high in physical strength, thus enabling various applications. However, the advantages of plastics that do not cause much corrosion or oxidation are adversely affecting the environment and preventing the food from maintaining proper guidance.

Recently, research on food packaging materials using natural materials as eco-friendly materials has been carried out as interest in environment and health has increased, but it is difficult to achieve high level of barrier properties such as metal and plastic materials There is a problem.

The present invention provides a film for a food packaging material comprising a barrier layer containing a natural substance for overcoming the disadvantages of the conventional food packaging material as described above.

The film for a food packaging material of the present invention can effectively block oxygen and moisture, including a barrier layer containing a natural product.

In addition, the film for food packaging materials of the present invention has excellent oxygen permeability, water permeability and interlaminar strength similar to or similar to films using existing oil-based adhesives by using an aqueous adhesive, excellent light transmittance and haze characteristics, A film for food packaging material is provided. The film for food packaging materials of the present invention is eco-friendly because it can replace an existing oily adhesive by using an aqueous adhesive.

According to one aspect,

A first substrate;

A second substrate; And

And a barrier layer including a natural material disposed between the first substrate and the second substrate,

Between the first substrate and the blocking layer; And between the second substrate and the barrier layer; A first water-based adhesive layer is provided on at least one of the first adhesive layer and the second adhesive layer.

According to another embodiment, there is provided a method of forming a barrier layer comprising: forming a barrier layer comprising a natural material on a first substrate; And

And bonding the second substrate or the third substrate with the first aqueous adhesive on the barrier layer to form a first aqueous adhesive layer.

The film for a food packaging material according to an embodiment of the present invention effectively prevents corruption of food, has sufficient transparency while having low oxygen permeability and water permeability, does not use a conventional oil-based adhesive, Friendly.

Hereinafter, specific details and possible implementations of the present invention will be described. However, for configurations not specifically described below, contents known to those skilled in the art can be applied to the object of the present invention.

In this specification, when a layer or member is referred to as being " on " another layer or member, it is not necessarily the case that a layer or member is in contact with another layer or member, And the case where another member exists.

Furthermore, when a component is referred to as " comprising " in this specification, it is to be understood that the component may include other components as well, without departing from the specification unless specifically stated otherwise.

[Food Packaging Film]

The film for a food packaging material according to an embodiment of the present invention includes:

A first substrate;

A second substrate; And

And a barrier layer including a natural material disposed between the first substrate and the second substrate,

Between the first substrate and the blocking layer; And between the second substrate and the barrier layer; And a second water-based adhesive layer.

The film for food packaging materials is environmentally friendly because it effectively prevents corruption of food, has sufficient transparency while having low oxygen permeability and water permeability, and does not use existing oil-based adhesives and therefore has little environmental impact.

According to one embodiment, the natural product does not contain carbohydrates. For example, the natural product does not include monosaccharides, disaccharides or polysaccharides.

According to one embodiment, the barrier layer may be coated on the first substrate. For example, the barrier layer may be, but is not limited to, directly contacting the first substrate.

According to one embodiment, the natural product comprises a protein.

According to one embodiment, the protein may be a protein derived from a natural source.

For example, the protein may be a whey protein, a whey protein, a soy protein isolate (SPI), a rice protein isolate (RPI), an oat protein isolate (OPI), a pea protein isolate , PPI), casein, sodium caseinate, corn zein, gelatin, Gluten, or any combination thereof.

When the natural product contains a protein, the protein forms a three-dimensional network structure in the blocking layer, thereby providing a blocking layer having a high level of oxygen barrier property, moisture barrier property, and transparency .

According to another embodiment, the natural product comprises a protein and, in addition to the protein, may further comprise a carbohydrate.

The carbohydrate includes at least one compound selected from monosaccharides, disaccharides and polysaccharides. According to one embodiment, the carbohydrate can comprise polysaccharides and can be, for example, Pullulan, Carrageenan, Chitosan, Starch, Agar, Pectin, And may further include any combination of these.

When the natural product further includes a carbohydrate in addition to the protein, the carbohydrate structurally supports the three-dimensional network structure of the protein formed in the blocking layer to improve the oxygen barrier property, water barrier property and transparency of the blocking layer have.

According to one embodiment, the content of the natural material may be 5 parts by weight to 99 parts by weight per 100 parts by weight of the barrier layer. For example, the content of the natural product may be at least 10 parts by weight, or at least 25 parts by weight, or at least 30 parts by weight per 100 parts by weight of the barrier layer. For example, the content of the natural material may be 85 parts by weight or less, 80 parts by weight or 75 parts by weight or less per 100 parts by weight of the barrier layer. When the content of the natural material satisfies the above range, There is an advantageous effect in terms of implementation of blocking performance and productivity. If the content of the natural product is less than 5 parts by weight, it is not enough to achieve oxygen and moisture barrier performance, and if it exceeds 99 parts by weight, the production efficiency becomes low.

According to one embodiment, the film for food packaging material comprises a first aqueous adhesive layer between the second substrate and the barrier layer.

The first aqueous adhesive layer may be formed using an aqueous adhesive known in the art.

According to one embodiment, the first water-based adhesive layer is formed of an aqueous polyurethane resin, a polyvinyl pyrrolidone resin, a polyvinyl alcohol resin, an aqueous acrylic resin, an epoxy resin, a phenol resin, a starch, . ≪ / RTI >

According to one embodiment, the thickness of the first aqueous adhesive layer may be between 1 μm and 5 μm. For example, the thickness of the first aqueous adhesive layer may be 3 탆 to 4 탆, but is not limited thereto. It is possible to maintain the flexibility of the film for the food packaging material when the thickness of the first water-based adhesive layer satisfies the above-mentioned range, and to prevent the film for food packaging material from being folded or creased The laminated structure can be maintained without being damaged.

According to one embodiment, the first substrate and the second substrate are each independently,

(PET), low density polyethylene (LDPE), polypropylene (PP), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethyleneterephthalate Polyimide (PI), oriented polypropylene (OPP), casting polypropylene (CPP), biaxially oriented polypropylene (BOPP), polyethylene 2,6-dicarboxylic naphthalate (PEN), polyether sulfone (PES), polyester (PE), polystyrene (PS), nylon (Ny) and paper.

According to another embodiment, at least one of the first substrate and the second substrate may be biodegradable.

According to one embodiment, the thicknesses of the first substrate and the second substrate may each independently be between 5 탆 and 100 탆. For example, the thickness of the first substrate and the second substrate may be between 7 탆 and 85 탆, or between 10 탆 and 70 탆. The flexibility of the film for the food packaging material can be maintained when the thickness of the first base material and the second base material satisfy the above-mentioned range, and the film for food packaging material is folded or wrinkled So that it is easy to make a desired shape.

According to one embodiment, the film for food packaging material further comprises a third substrate disposed between the barrier layer and the second substrate, and a second aqueous adhesive layer between the second substrate and the third substrate can do.

According to one embodiment, the film for food packaging material comprises: a first substrate; A barrier layer disposed on the first substrate; A first aqueous adhesive layer disposed on the barrier layer; A third base material disposed on the first water-base adhesive layer; A second aqueous adhesive layer disposed on the third substrate; And a second substrate disposed on the second water-based adhesive layer. However, the laminated structure of the film for food packaging material is not limited thereto.

The description related to the third base can refer to the description of the first base and the second base.

The description of the second aqueous adhesive layer can be referred to the description of the first aqueous adhesive layer.

According to one embodiment, the film for food packaging material may have an oxygen permeability of less than 3 cc / (m ² day), for example less than 1 cc / (m ² day).

Also, according to one embodiment, the moisture permeability of the film for food packaging material may be less than or equal to 5 g / (m ² day), for example less than or equal to 3 g / (m ² day).

According to one embodiment, the light transmittance of the film for the food packaging material may be 80% or more, for example 85% to 95%.

Also, according to one embodiment, the haze of the film for the food packaging material may be 5%.

[Production method of film for food packaging material]

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming a barrier layer including a natural material on a first substrate; And

And bonding the second substrate or the third substrate with the first aqueous adhesive on the barrier layer to form a first aqueous adhesive layer.

The above-mentioned contents can be referred to for the description of the film for food packaging material manufactured by the method for manufacturing film for food packaging material.

According to one embodiment, the step of forming the barrier layer may use a natural material coating agent for forming the barrier layer.

For example, the natural material coating agent for forming the barrier layer may include the natural material, and may further include a filler and a solvent.

The description on the natural product can be referred to the above. For example, the natural product may not contain carbohydrates. In another example, the natural product may comprise a protein.

According to one embodiment, the filler is selected from the group consisting of sorbitol, fructose, sucrose, mannitol, propylene glycol, glycerol, polyethylene glycol, Or any combination thereof.

The filler is disposed in a hole between three-dimensional network structures formed by the natural product to fill the gap, thereby increasing the oxygen barrier property and moisture barrier property of the barrier layer, and smoothing the surface can do.

The content of the filler may be 5 parts by weight to 25 parts by weight, for example, 7 parts by weight to 15 parts by weight, per 100 parts by weight of the coating composition for forming a barrier layer. When the content of the filler satisfies the above range, there is an advantageous effect in terms of appearance and mechanical properties of the film, oxygen barrier property and moisture barrier property. If the content of the filler is less than 5 parts by weight, the coating film may crack and may peel off from the base film. If the content of the filler exceeds 25 parts by weight, the filler may migrate when the dry film is stored for a long period of time, There is a problem that the oxygen barrier property or the moisture barrier property is lowered.

According to one embodiment, the solvent may be water, but is not limited thereto. For example, distilled water or purified water may be used as the solvent.

The content of the solvent may be 50 parts by weight to 99 parts by weight, for example, 70 parts by weight to 95 parts by weight, per 100 parts by weight of the natural material coating agent for forming a barrier layer

The natural material coating agent for forming the barrier layer may be provided in a thickness of 0.1 탆 to 70 탆. The thicker the thickness of the natural material coating material for barrier layer formation is, the higher the oxygen barrier property becomes, and the thinner the thickness, the more economical in the manufacturing process.

According to one embodiment, the step of removing at least a portion of the solvent in the coating composition to form the barrier layer may be performed by a method of hot air drying.

For example, the step of removing at least a portion of the solvent in the coating composition to form the barrier layer may be performed at a temperature of 60 ° C to 150 ° C for 1 minute to 5 minutes using a hot air drier.

According to one embodiment, the step of forming the first water-based adhesive layer may further include the step of applying the first water-based adhesive on the barrier layer to a thickness of 3 m to 10 m. For example, the first aqueous adhesive may be applied in a thickness of 5 占 퐉 to 10 占 퐉, or 7 占 퐉 to 8 占 퐉. Thus, when the first aqueous adhesive is applied in a thickness of 3 탆 to 10 탆, the thickness of the first aqueous adhesive layer after drying can be formed to 1 탆 to 5 탆.

The first aqueous adhesive may include an aqueous polyurethane resin, a polyvinyl pyrrolidone resin, a polyvinyl alcohol resin, an aqueous acrylic resin, an epoxy resin, a phenolic resin, a starch, or any combination thereof.

According to one embodiment, the step of forming the first water-based adhesive layer may be performed by a dry lamination method, but not limited thereto, and various methods known in the art can be used.

The step of forming the first water-base adhesive layer may be a step of bonding the third base material to the barrier layer using a first water-based adhesive.

For example, in the method for producing a film for a food packaging material,

The step of forming the first water-base adhesive layer is a step of bonding the third base material to the barrier layer using a first water-based adhesive,

The method for producing a film for food packaging material

And bonding the second base material to the third base material using a second aqueous adhesive and forming a second aqueous adhesive layer on the third base material.

The description of the second aqueous adhesive can be referred to the description of the first aqueous adhesive.

Further, the description of the first base material, the second base material, the third base material, the first aqueous adhesive agent, and the second aqueous adhesive agent can be referred to the above description.

The following examples illustrate the invention without limiting the scope of the invention.

[Example]

Example  1: Film for food packaging Manufacturing example

(1) Preparation of aqueous adhesive

A four-necked flask equipped with a reflux condenser is placed on the heating mantle, and 11 g of sodium dodecyl sulfate (emulsifier) is added to 200 g of distilled water with stirring to disperse the emulsifier preferentially. After dispersing for 30 minutes, 48 g of monomer acrylic acid (functional monomer) and 244 g of butyl acrylate (main monomer) were slowly injected for 1 hour while stirring to prepare an initial emulsion. 0.92 g of ammonium persulfate aqueous dispersion was added as an initiator, and the reaction was continued at 80 ° C for 6 to 7 hours at a constant rate of 100 rpm to remove unreacted monomers to obtain an aqueous adhesive.

(2) Barrier layer  Of natural product coating agent for forming

8 g of protein was slowly added to 92 g of distilled water with stirring, and then 8 g of sorbitol was added to the protein aqueous solution. After the pH of the reaction mixture was adjusted to 9 using 1N NaOH, the reaction mixture was stirred at 300 rpm using a mechanical stirrer, heated to 90 캜, heated for 30 minutes, and then cooled.

(3) Barrier layer  coating

About 1 g to 2.5 g of the natural material coating agent for forming a barrier layer was dropped onto the base film, and the thickness of the PET film was adjusted to about 50 탆 using an applicator (YBA-5) Respectively. Next, the coated film was dried using a hot-air drier at about 120 ° C for 3 minutes to 5 minutes to prepare a coating film.

(4) Production of films for food packaging

The water-based adhesive was applied to the top of the coating film to a thickness of 7 탆 to 8 탆, and the Ny substrate was laminated using a dry lamination method. The aqueous adhesive was applied on the Ny substrate to a thickness of 7 탆 to 8 탆, and the LDPE substrate was laminated using a dry lamination method.

Comparative Example  One

A film for food packaging material was prepared in the same manner as in Example 1, except that a urethane resin mixed with ethyl acetate as an oily adhesive was used instead of the water-based adhesive without forming a barrier layer.

Comparative Example  2

A film for food packaging material was prepared in the same manner as in Example 1 except that no barrier layer was formed.

Comparative Example 3

A film for food packaging material was prepared in the same manner as in Example 1 except that a urethane resin mixed with ethyl acetate as an oily adhesive was used in place of the aqueous adhesive.

[Evaluation example]

Evaluation example  1: Evaluation of physical properties of film for food packaging materials

The oxygen transmission rate (OTR), water vapor transmittance rate (WVTR), interlaminar strength, light transmittance and haze of the film for food packaging material of Example 1 and Comparative Examples 1 to 3 were measured , And the results are shown in Table 1 below.

Oxygen permeability is expressed by the amount of oxygen permeating the coating film for 24 hours under conditions of a temperature of 23 ± 1 ° C. and an O ₂ concentration of 100%, and was measured using an OXTRAN 2/21 Oxygen Permeability Tester of MOCON Corporation.

The water permeability is expressed as the amount of water vapor permeating the coating film for 24 hours under the conditions of 37 ± 1 ° C. and 100% of humidity, and was measured using a PERMATRAN-W 3/33 water vapor permeability tester of MOCON Corporation.

Light transmittance and haze were measured using a NIPPON DENSHOKU, NDH 7000 haze meter.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 ^{OTR (cc / m 2 · day} ) 0.13 90.58 90.55 0.15 WVTR (g / m ² · day) 1.40 1.42 1.40 1.44 Interlayer strength (gf / 15 mm) 545.7 532.8 533.1 540.3 Light transmittance (%) 89.48 89.32 89.42 89.45 Haze (%) 4.59 5.18 4.67 5.09

Referring to Table 1, the film for a food packaging material according to an embodiment of the present invention comprises:

By using a barrier layer containing natural materials and an aqueous adhesive, it is environmentally friendly, unlike the case of using an oil-based adhesive, has excellent oxygen permeability and water permeability similar to or similar to films using a conventional oil-based adhesive, And excellent haze characteristics.

Claims (14)

A first substrate;
A second substrate; And
And a barrier layer including a natural material disposed between the first substrate and the second substrate,
Between the first substrate and the blocking layer; And between the second substrate and the barrier layer; A first water-based adhesive layer on at least one of the first and second water-
Wherein the barrier layer is in direct contact with the first aqueous adhesive layer,
Wherein the natural product comprises a protein,
The protein may be selected from the group consisting of whey protein, whey protein, soy protein isolate (SPI), rice protein isolate (RPI), pea protein isolate (PPI), sodium caseinate, gelatin ), Or any combination thereof,
Wherein the first aqueous adhesive layer is formed from a food packaging material, which comprises an aqueous polyurethane resin, a polyvinyl pyrrolidone resin, a polyvinyl alcohol resin, an aqueous acrylic resin, an epoxy resin, a phenolic resin, a starch, Film for reuse. The method according to claim 1,
Wherein the natural product does not contain carbohydrates. delete The method according to claim 1,
Wherein the natural product further comprises a carbohydrate,
Wherein the carbohydrate comprises Pullulan, Carrageenan, Chitosan, Starch, Agar, Pectin or any combination thereof. delete The method according to claim 1,
Wherein the first water-base adhesive layer has a thickness of 1 탆 to 5 탆. The method according to claim 1,
Wherein the first substrate and the second substrate are each independently,
(PET), low density polyethylene (LDPE), polypropylene (PP), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethyleneterephthalate Polyimide (PI), oriented polypropylene (OPP), casting polypropylene (CPP), biaxially oriented polypropylene (BOPP), polyethylene 2,6-dicarboxylic naphthalate for food packaging material selected from polyethylene 2,6-dicarboxyl naphthalate (PEN), polyethersulfone (PES), polyester (PE), polystyrene (PS), nylon (Ny) film. The method according to claim 1,
Wherein the thickness of the first substrate and the thickness of the second substrate are independently from 5 mu m to 100 mu m. The method according to claim 1,
Further comprising a third substrate disposed between the barrier layer and the second substrate,
And a second aqueous adhesive layer between the second substrate and the third substrate. The method according to claim 1,
Wherein the film for food packaging material has an oxygen permeability of 3 cc / (m ² day) or less and a water permeability of 5 g / (m ² day) or less. The method according to claim 1,
Wherein the film for food packaging material has a light transmittance of 80% or more and a haze of the film for food packaging material is 5% or less. Forming a barrier layer comprising a natural material on the first substrate; And
The third base material is adhered onto the barrier layer using a first water-based adhesive And forming a first aqueous adhesive layer,
Wherein the barrier layer is in direct contact with the first aqueous adhesive layer,
Wherein the natural product comprises a protein,
The protein may be selected from the group consisting of whey protein, whey protein, soy protein isolate (SPI), rice protein isolate (RPI), pea protein isolate (PPI), sodium caseinate, gelatin ), Or any combination thereof,
Wherein the first aqueous adhesive layer is formed from a food packaging material, which comprises an aqueous polyurethane resin, a polyvinyl pyrrolidone resin, a polyvinyl alcohol resin, an aqueous acrylic resin, an epoxy resin, a phenolic resin, a starch, A method for producing a refill film. 13. The method of claim 12,
The step of forming the barrier layer may include using a natural material coating agent for forming a barrier layer,
Wherein the natural material coating material for forming a barrier layer comprises the natural material, further comprising a filler and a solvent. 13. The method of claim 12,
Wherein the step of forming the first aqueous adhesive layer uses a dry lamination method.