KR102247843B1 - Method of eco-friendly food flexible packaging coating materials containing biodegradable catalyst - Google Patents

Abstract

The present invention relates to a method for manufacturing a flexible packaging material for eco-friendly food substitute for plastic containing a biodegradable catalyst. More specifically, the method comprises the steps of: preparing an inner layer composition and an outer layer composition; and co-extruding the prepared inner layer composition and outer layer composition. The step of preparing the inner layer composition comprises the steps of: preparing a prepolymer by mixing a polyol, a dimethylol propionic acid (DMPA), an N-methylpinolidone (NMP) solution, and isocyanate; neutralizing the prepolymer with a neutralizing agent diluted in the NMP solution, adding distilled water to the neutralized prepolymer for water dispersion, and adding a chain extender to prepare water-dispersed polyurethane; preparing a water-soluble acrylic polyurethane by adding an acrylic monomer, a biodegradable catalyst, and an initiator to the water-dispersed polyurethane and stirring the same; and adding a calcium-based compound, sodium perborate, and an acetic acid to the water-soluble acrylic polyurethane. The step of preparing the outer layer composition comprises a step of mixing polyolefin, an ethylenediaminetetraacetic acid (EDTA), calcium lactate, a metal stearic acid, and drometrizole.

Description

A method of manufacturing flexible packaging materials for eco-friendly foods for replacing plastics containing biodegradable catalysts {METHOD OF ECO-FRIENDLY FOOD FLEXIBLE PACKAGING COATING MATERIALS CONTAINING BIODEGRADABLE CATALYST}

The present invention relates to a method for manufacturing a flexible packaging material for eco-friendly foods for replacing plastics comprising a biodegradation catalyst, and in more detail, the steps of preparing an inner layer composition and an outer layer composition; Coextrusion of the prepared inner layer composition and outer layer composition, and the step of preparing the inner layer composition includes polyol, dimethylol propionic acid (DMPA), N-methylpinolidone (NMP) solution, and Mixing isocyanate to prepare a prepolymer; Neutralizing the prepolymer with a neutralizing agent diluted in N-methylpinolidone (NMP) solution, adding distilled water to the neutralized prepolymer to disperse it, and then adding a chain extender to prepare a water-dispersible polyurethane; Adding an acrylic monomer, a biodegradation catalyst, and an initiator to the water-dispersible polyurethane, followed by stirring to prepare a water-soluble acrylic polyurethane; And adding a calcium-based compound, sodium perborate, and acetic acid to the water-soluble acrylic polyurethane, and preparing the outer layer composition includes polyolefin, ethylenediaminetetraacetic acid (EDTA), calcium lactate, metal stearic acid, and It relates to a method for manufacturing a flexible packaging material for eco-friendly food, characterized in that it comprises the step of mixing drometrisol.

Flexible packaging is a packaging material made in the form of a bag or film according to the characteristics of the contents by making flexible materials such as plastic film, paper, aluminum foil and fiber in the form of a single layer or a multi-layered layer, and a packaging method using the same. it means.

Flexible packaging is the most economical means of packaging for storing and distributing food, alcohol, pharmaceuticals, general consumables and other products that require extended shelf life. It can be designed with barriers made to fit the product being packaged for the type of final consumption. On the other hand, other barrier packaging formats are generally provided to fit all sizes. Current flexible packaging can be manufactured in a wide variety of innovative shapes, sizes and shapes, and can include features such as open and close zippers and spouts.

Flexible packaging consumes less resources and energy than other types of packaging. Not only does it have the advantage of standardized solid packaging, but it also provides great savings in terms of packaging cost, material usage, and transportation cost. Using flexible packaging can minimize package transport costs from package processors to content suppliers, retailers and end consumers. In particular, when the contents are not filled, the space can be minimized compared to solid packaging, as well as partial work can be performed through the roll material at the contents filling place. For this reason, transportation costs for pre-production packaging without contents are minimized.

The most important point in flexible packaging is to select and use the most suitable packaging material for the characteristics of the contents and the method of operation for the preservation of the contents. Materials that can be deteriorated by moisture, products that need to be dried, products that need to be kept in a vacuum to prevent spoilage, foods that require a lot of hygiene, foods to be processed using a microwave oven, and packaging according to various contents And physical, chemical, and functional properties are appropriately selected and used. As a single material, there are very few materials that satisfy the protection, quality maintenance and operation method of the contents, and all matters according to the manufacturing process, but in the case of flexible packaging, various materials are used in combination to satisfy the needs as much as possible.

Among the flexible packaging materials, the demand for eco-friendly (biodegradable) films, PVA (polyvinyl alcohol) films, biaxially oriented polypropylene (BOPP) films, and materials using aluminum foil and paper flexible packaging continues to expand. The demand for LDPE (low density polyethylene) has already reached its saturation point as the market has matured.

Korean Patent Registration No. 10-1997524

It is harmless to the human body by complementing the shortcomings of existing paper packaging materials (including multi-layered laminated packaging materials) and containers (including plastic products), saving resources (reduction, reusability, recyclability, recyclability, ease of disposal) and eco-friendly incineration Its purpose is to provide an eco-friendly and renewable food flexible packaging material manufacturing method that has excellent ease of decomposition during embedding and gives alkali dissociation properties that can protect the environment.

The present invention has been devised to solve the above problems, the steps of preparing an inner layer composition and an outer layer composition; Coextrusion of the prepared inner layer composition and outer layer composition, and the step of preparing the inner layer composition includes polyol, dimethylol propionic acid (DMPA), N-methylpinolidone (NMP) solution, and Mixing isocyanate to prepare a prepolymer; Neutralizing the prepolymer with a neutralizing agent diluted in N-methylpinolidone (NMP) solution, adding distilled water to the neutralized prepolymer to disperse it, and then adding a chain extender to prepare a water-dispersible polyurethane; Adding an acrylic monomer, a biodegradation catalyst, and an initiator to the water-dispersible polyurethane, followed by stirring to prepare a water-soluble acrylic polyurethane; Including the step of adding a calcium-based compound, sodium perborate and acetic acid to the water-soluble acrylic polyurethane, the step of preparing the outer layer composition is polyolefin, ethylenediaminetetraacetic acid (EDTA), calcium lactate, metal stearic acid and draw It provides a method for manufacturing a flexible packaging material for eco-friendly food for plastic replacement, characterized in that it comprises the step of mixing mettrisol.

According to the present invention, it has excellent oil resistance, water resistance, and thermal bonding strength, biodegrades in nature when discarded after use, and is easy to regenerate (recycle) with alkali dissociation properties, prevents bacterial growth and suppresses gas generation for long-term storage of food. It is possible to manufacture a food flexible packaging material that facilitates.

Hereinafter, the present invention will be described in more detail.

The food flexible packaging material manufactured by the manufacturing method of the present invention is composed of an inner layer and an outer layer, and the inner layer functions as a base film for packaging food or food materials, and has excellent barrier properties of moisture or gas, and the outer layer is It is laminated on one surface of the inner layer and has an ultraviolet ray blocking effect.

A method for manufacturing a flexible packaging material for eco-friendly food for plastic replacement according to an embodiment of the present invention,

Preparing an inner layer composition and an outer layer composition; And coextruding the prepared inner layer composition and outer layer composition,

The step of preparing the inner layer composition may include preparing a prepolymer by mixing polyol, dimethylol propionic acid (DMPA), N-methylpinolidone (NMP) solution, and isocyanate; Neutralizing the prepolymer with a neutralizing agent diluted in N-methylpinolidone (NMP) solution, adding distilled water to the neutralized prepolymer to disperse it, and then adding a chain extender to prepare a water-dispersible polyurethane; Adding an acrylic monomer, a biodegradation catalyst, and an initiator to the water-dispersible polyurethane, followed by stirring to prepare a water-soluble acrylic polyurethane; And adding a calcium-based compound, sodium perborate and acetic acid to the water-soluble acrylic polyurethane,

The step of preparing the outer layer composition includes mixing polyolefin, ethylenediaminetetraacetic acid (EDTA), calcium lactate, metal stearic acid, and drometrisol.

In the step of preparing the prepolymer, the polyol is a polyether polyol, preferably polytetramehtyleneglycol (PTMG), and 15 to 25 parts by weight may be used based on 100 parts by weight of the prepolymer, and the amount used is 15 parts by weight. If it is less than parts, there is a concern that the cohesive strength may decrease, and if it exceeds 25 parts by weight, there is a concern that the hydrolysis resistance is lowered.

The dimethylol propionic acid (DMPA) may be used in 15 to 25 parts by weight based on 100 parts by weight of the prepolymer, and if the amount is less than 15 parts by weight, water dispersion stability may be deteriorated, and if it exceeds 25 parts by weight There is a fear that the hydrolysis resistance may decrease.

Isocyanate is an aliphatic diisocyanate, 4,4-dicyclohexanemethane diisocyanate (4,4'-dicyclohexylmethane diisocyanate, H12MDI), isophorone diisocyanate (IPDI), 1,4-cyclohexanediisocyanate (1, 4-cyclohexylmethane diisocyanate, CHDI) or 4,4'-diphenylmethane diisocyanate (MDI) as an aromatic diisocyanate, 2,4- or 2,6-toluene diisocyanate (2,4 -or 2,6-toluene diisocyanate, TDI) can be selected and used, preferably isophorone diisocyanate (IPDI). IPDI may be used in an amount of 50 to 65 parts by weight based on 100 parts by weight of the prepolymer, and if it is out of the above range, polyurethane may not be sufficiently synthesized or water dispersion stability may be deteriorated.

The step of preparing the water-dispersible polyurethane includes 25 to 45 parts by weight of the prepared prepolymer and 1 to 3 parts by weight of the N-methylpinolidone (NMP) solution based on 100 parts by weight of the water-dispersion polyurethane. Neutralizing the prepared prepolymer by mixing parts; A step of stirring while dropping 40 to 60 parts by weight of distilled water based on 100 parts by weight of the water-dispersible polyurethane; And adding 5 to 15 parts by weight of a chain extender based on 100 parts by weight of the water-dispersed polyurethane and stirring. do.

The neutralizing agent may be used by selecting from triethylamine (TEA), trimethylamine (TMA) or sodium hydroxide (NaOH), preferably triethylamine (TEA), If the amount is less than 2 parts by weight, the water dispersion stability may be deteriorated, and if it exceeds 6 parts by weight, the storage stability may be deteriorated, and there is a fear that physical properties may deteriorate due to an addition reaction.

Ethylene diamine (EDA) is used as the chain extender, and if the amount is less than 5 parts by weight, the chain extension effect may be insufficient, and if it exceeds 15 parts by weight, storage stability may be deteriorated.

The step of preparing the water-soluble acrylic polyurethane includes 70 to 85 parts by weight of the water-dispersible polyurethane, 10 to 25 parts by weight of an acrylic monomer, 1 to 3 parts by weight of a biodegradation catalyst, and 1 to 3 parts by weight of an initiator based on 100 parts by weight of the water-soluble acrylic polyurethane. It is characterized by stirring by adding parts by weight.

The acrylic monomer may be used by selecting from methyl methacrylate, methacrylate, acrylonitrile, ethyl acrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, methacrylonitrile, and vinyl acetate. , Preferably, methyl methacrylate (MMA) is used, and if the amount is less than 10 parts by weight, the durability and water resistance improvement effect may be insufficient, and if it exceeds 25 parts by weight, storage stability may be deteriorated. .

The biodegradation catalyst performs a function of reducing the molecular weight and biodegradation of acrylic polyurethane through photooxidation reaction, and ferric acetyl carbamate, aluminum acetyl carbamate, manganese acetyl carbamate, or a mixture thereof may be used as the acetyl carbamate metal salt. It is preferable to use 1 to 3 parts by weight or more. When used in less than 1 part by weight, there is a disadvantage that the final biodegradation period is prolonged. In addition, if it exceeds 3 parts by weight, the effect is excellent, but there is a disadvantage of increasing the price.

1 to 3 parts by weight of an initiator for polymerization is used, and the initiator is AIBN (2,2'-azo-bis (isobutyronitrile)) or ABN (2,2'-azo-bis (2-methylbutyronitrile)). Used, preferably AIBM. On the other hand, when the content of the initiator is less than 1 part by weight, the efficiency of the initiator decreases and the reaction does not proceed easily, and when the amount of the initiator exceeds 3 parts by weight, there is a problem in that a gel is generated due to an instantaneous exothermic reaction.

In the step of adding a calcium-based compound, sodium perborate, and acetic acid to the water-soluble acrylic polyurethane, the calcium-based compound includes calcium ferrocyanide, calcium sorbate and calcium casein, and the step includes 92 to 96 weight of the water-soluble acrylic polyurethane It is characterized in that 2 to 6 parts by weight of the calcium-based mixed compound, 1 to 2 parts by weight of sodium perborate, and 1 to 2 parts by weight of acetic acid are added to the part.

In general, in the packaging material manufacturing method, inorganic pigments are widely used not only to reduce the cost of formulation, but also to further improve certain properties of the coating formulation during manufacture or storage of the packaging material, or during or after application of the coating agent to the packaging material. Clay and calcium carbonate are the most commonly used inorganic pigments. Clay has the advantage of obtaining high white paper gloss and printing gloss as a plate-mounted structure, but has the disadvantage of low fluidity and increased binder demand.In the case of calcium carbonate, fluidity, adhesion, ink repair, paper brightness, and opacity On the other hand, there is a problem in that the chemical stability of the packaging material composition against calcium cations is further required.

Therefore, the present inventors have tried to find a calcium compound that is safe among various calcium compounds and can improve the physical and chemical properties of the flexible packaging material, and through a comparative experiment, calcium ferrocyanide, calcium sorbate, and calcium casein are contained in the soft packaging material compared to calcium carbonate. It was found that induction, water resistance, air permeability, moisture permeability, and heat-sealing properties were improved, and in the case of the flexible packaging material added by mixing calcium ferrocyanide, calcium sorbate and calcium casein at the same ratio, each calcium-based compound was added. It was confirmed that it has superior physical properties compared to the flexible packaging material.

The calcium compound is preferably contained in 2 to 6 parts by weight, and when used in an amount of less than 2 parts by weight, the addition effect is weak, and when it exceeds 6 parts by weight, the physical properties of the flexible packaging material are deteriorated.

The sodium perborate (Sodium perborate, NaBO ₃ ) is preferably contained in 1 to 2 parts by weight. If the content of sodium perborate is less than 1 part by weight, the oil resistance and waterproofing properties of the final flexible packaging material may not be increased, and the viscosity synergistic effect may not reach the desired level.If it exceeds 2 parts by weight, disadvantages may occur due to the decrease in the relative content of other ingredients. In addition, the viscosity of the inner layer composition of the flexible packaging material may be excessively increased, and thus workability may decrease.

In addition, the present inventors may further add acetic acid together with the calcium-based mixed compound and sodium perborate in order to prevent the physical properties of the flexible packaging material from deteriorating by the calcium cation, and adding 1 to 2 parts by weight of the acetic acid. It is characterized.

The added acetic acid can form calcium acetate through ionic bonding with the dissociated calcium cations, and the present inventors have confirmed that the water resistance, oil resistance, and heat sealing properties of the flexible packaging material are slightly improved when acetic acid is added.

The outer layer composition may be prepared by mixing polyolefin, ethylenediaminetetraacetic acid (EDTA), calcium lactate, metal stearic acid, and drometrisol.

The composition for preparing the outer layer is 75 to 95 parts by weight of polyolefin resin, 1 to 10 parts by weight of ethylenediaminetetraacetic acid (EDTA), 1 to 10 parts by weight of calcium lactate, 1 to 10 parts by weight of metal stearic acid, and drometrisol 0.1 to 1 parts by weight, preferably 93 parts by weight of polyolefin resin, 2 parts by weight of ethylenediaminetetraacetic acid (EDTA), 2 parts by weight of calcium lactate, 2 parts by weight of metal stearic acid, 1 part by weight of drometrisol Can include.

The ethylenediaminetetraacetic acid (EDTA) is used as a discoloration inhibitor, and prevents the binding of metal ions, thereby preventing acid damage, deterioration, and discoloration, and preventing the formation of precipitates, and the ethylenediaminetetraacetic acid is 1 It may contain ~ 10 parts by weight.

The calcium lactate is called calcium lactate, and functions to facilitate long-term storage of food by preventing bacterial growth and suppressing gas generation, and to control the acidity of packaging products, and the calcium lactate is 1 to 10 parts by weight may be included.

The metal stearic acid may include at least one of iron (III) stearate, ferric hydroxystearate, or copper stearate (copper (II) stearate), preferably iron (III) stearate. ) stearate), and the metal stearic acid may be included in 1 to 10 parts by weight.

The metal stearic acid exhibits excellent deodorizing effect against odors such as hydrogen sulfate and mercaptan, as well as ammonia and amines. Stearic acid is excellent in thermal stability and has the advantage of being able to continuously maintain the deodorizing effect even in the manufacturing process of plastic, urethane, rubber, etc., which is accompanied by a high-temperature heat treatment process.

Metal ions contained in metal stearic acid may be any one that forms complex ions by ionic bonding with a substance that is a source of odor, but in the present invention, Fe ²⁺ or Cu ²⁺ is preferable among metal ions having a large ionization tendency, and the metal ions Silver plays a role of removing odors from the air by forming complex ions such as trimethylamine (TMA), NH ₃ , H _{2 S, and methyl mercaptan, which are representative sources of odor.}

Drometrisol is represented by the following [Chemical Formula 1] as 2-(benzotriazol-2-yl)-4-methylphenol, and the dromethrizol has an effect of blocking ultraviolet rays and is preferably 0.1 to 1 weight Additional may be included.

[Formula 1]

Hereinafter, the present invention will be described in more detail through examples and experimental examples. However, these examples are only for helping the understanding of the present invention, and the scope of the present invention is not limited to these examples in any sense.

<Preparation of reagents>

The polyol used in the preparation of the water-soluble polyurethane aqueous dispersion is 1mmHg with polytetramehtyleneglycol (PTMG) (Mw=1,800 g/mole) of ether type and vacuum drying at 60℃ for about 10 hours or more to remove moisture. Was used. In order to introduce a hydrophilic functional group in the urethane, dimethylol propionic acid (DMPA) was used as it was without further stasis. Triethylamine (TEA) was used as the neutralizing agent, and ethylenediamine (EDA) was used as the chain extender.

The acrylic monomer used in the manufacture of the acrylic-polyurethane hybrid was methyl methacrylate (MMA), ferric acetyl carbamate was used as the biodegradation catalyst, and azobisisobutyronitrile (2, 2'-azobis isobutyronitrile, AIBN) was used. As other solvent, n-methyl-2-pyrrolidinone (NMP) was used.

<Example 1>

(1) Preparation of inner layer composition

First, Waterborne Polyurethane Dispersions (WPUDs) were synthesized. This is produced by a'two shot process' method of reacting prepolymer with PTMG and DMPA first in the mixing process and then adding isocyanate. The two inlets of the stirrer are purged with nitrogen, and the other inlet is blocked and distilled water is added dropwise while proceeding.

1) Preparation of NCO-prepolymer having an isocyanate group (NCO)

First, put PTMG in a stirrer, melt it in a vacuum oven (100°C), and install it in an oil bath. The impeller speed of the stirrer is fixed at 100 rpm and the air inside the stirrer is replaced with nitrogen for 30 minutes to start the reaction. Then, DMPA dried in a vacuum in advance is put into a stirrer without changing the reaction conditions and dissolved in PTMG.

After stirring for about 1 hour, NMP and IPDI are added. After stirring for an additional hour as it is, the temperature is lowered to 50° C., and then stirred for an additional hour to obtain a NCO-prepolymer having an isocyanate group (NCO).

PTMG DMPA NMP IPDI Total (wt%) 18 22 3 57 100

2) Preparation of water-dispersible polyurethane dispersion

A neutralizing agent TEA diluted with an NMP solution is added to the prepared NCO-prepolymer and neutralized. Then, a certain amount of distilled water is added dropwise at a constant speed, and the stirring speed is increased to 300 rpm. Thereafter, EDA is put in a stirrer and stirring is performed for a total of 3 hours in that state to obtain a water-dispersible polyurethane dispersion.

NCO-prepolymer NMP TEA Distilled water EDA Total (wt%) 34 2 4 50 10 100

3) Preparation of acrylic-urethane hybrid dispersion

A water-soluble polyurethane dispersion prepared in the above manner is prepared. After stabilizing the MMA and the water-soluble polyurethane dispersion at a high speed of 1500 rpm for about 30 minutes, the impeller speed of the stirrer was installed in an oil bath and replaced with nitrogen for 30 minutes. When the inside of the stirrer is under nitrogen, a solution in which AIBN and ferric acetyl carbamate are dissolved in MMA is added and stirred at 300 rpm for about 1 hour to form a liquid water-soluble acrylic-urethane hybrid dispersion (WAUDs). To manufacture.

Water-soluble polyurethane dispersion MMA Ferric acetyl carbamate IPDI Total (wt%) 76 20 2 2 100

4) Addition of calcium compound, sodium perborate and acetic acid

An inner layer composition was prepared by mixing 1 wt% of calcium ferrocyanide, calcium sorbate, and calcium casein, respectively, 1.5 wt% of sodium perborate, and 1.5 wt% of acetic acid to 94 wt% of the prepared liquid aqueous acrylic-urethane hybrid dispersion solution. I did.

(2) Preparation of outer layer composition and manufacture of flexible packaging material

93 wt% of polyolefin resin, 2 wt% of ethylenediaminetetraacetic acid (EDTA), 2 wt% of calcium lactate, 2 wt% of iron (III) stearate, and 1 wt% of drometrisol were mixed to prepare an outer layer composition. Was prepared.

Thereafter, the inner layer and outer layer compositions are coextruded in the form of a two-layered coextrusion multilayer film through one coextrusion die, and then the coextruded multilayer film is cooled with water and then compressed with a pressing roller to form a food flexible packaging material. Was prepared.

<Comparative Example 1>

In Example 1, in place of the calcium ferrocyanide, calcium sorbate, and calcium casein, 3 wt% of the prepared liquid water-soluble acrylic-urethane hybrid dispersion solution was added to prepare a food flexible packaging material in the same manner as in Example 1.

<Comparative Example 2>

In Example 1, 3 wt% of calcium carbonate was added instead of calcium ferrocyanide, calcium sorbate, and calcium casein to prepare a food flexible packaging material in the same manner as in Example 1.

<Comparative Example 3>

In Example 1, 3 wt% of a liquid water-soluble acrylic-urethane hybrid dispersion solution was added instead of sodium perborate and acetic acid to prepare a food flexible packaging material in the same manner as in Example 1.

<Comparative Example 4>

In Example 1, instead of 1 wt% drometrisol, 1 wt% of polyolefin was added to prepare a food flexible packaging material in the same manner as in Example 1.

<Comparative Example 5>

In Example 1, 1 wt% of homosalate was added instead of 1 wt% of drometrisol to prepare a food flexible packaging material in the same manner as in Example 1. The homosalate is a material known as an ultraviolet absorber.

<Experimental Example 1>

The prepared food flexible packaging material was tested for physical properties under the same conditions, and the results are summarized in Table 4.

Test Items Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Food packaging safety fitness fitness fitness fitness fitness fitness Alkaline dissociation and dispersibility has exist has exist has exist has exist has exist has exist Induction resistance ◎ ○ △ ◎ ◎ ◎ Domestic water ◎ × △ ○ ◎ ◎ Speculation ◎ △ ○ ◎ ◎ ◎ Moisture permeability ◎ × △ ○ ◎ ◎ Thermal bonding strength ◎ ◎ ○ ○ ◎ △ Legend) ◎Excellent, ○Excellent, △Medium, ×Insufficient
Water vapor transmission rate: ◎< 30mg/m ² , ○30~50 mg/m ² , △50~200mg/m ² , ×> 200mg/m ²
Air permeability: ◎< 5cc/m ² , ○5~30cc/m ² , △30~60cc/m ² , ×> 60cc/m ²
Thermal bonding strength: ◎> 1,200 g/37mm, ○900~1,200 g/37mm, △800~900 g/37mm, ×< 800 g/37mm

<Test method>

Induction resistance: KS M 7124:2008

Domestic water supply: KS M 7025: 2012:12

Speculative prayer: KS M 7020: 2006:11

Water vapor transmission rate (gravity method): KS M ISO 2528

Thermal adhesion strength: self test

The oil resistance of the food flexible packaging material produced by the present invention was tested by the method of KS M 7124:2008, the water resistance was tested by the method of KS M 7025:2012:12, and the air permeability was tested by the method of KS M 7020:2006:11. It was tested, and the moisture permeability was tested by the method of KS M ISO 2528, and the thermal bonding (heat sealing) strength was tested through a self-test.

Referring to Table 4, in the case of Comparative Example 1 in which calcium ferrocyanide, calcium sorbate, and calcium casein were not added, it was confirmed that the physical properties of the flexible packaging material were deteriorated, except for the thermal adhesive strength, compared to Example 1, and in particular, water resistance It was confirmed that the degree and moisture permeability were significantly lowered compared to Example 1.

In the case of Comparative Example 2 in which calcium carbonate was added instead of calcium ferrocyanide, calcium sorbate, and calcium caseinate, it was confirmed that the water resistance and moisture permeability were slightly improved compared to that of Comparative Example 1, but when compared to Example 1, the water resistance and moisture permeability were decreased. Indicated.

In the case of Comparative Example 3, in which a food flexible packaging material was prepared by excluding sodium perborate and acetic acid, it was confirmed that the water resistance and moisture permeability were slightly lowered compared to Example 1, and the thermal adhesive strength was also lowered.

In the case of Comparative Example 5 in which homosalate known as an ultraviolet absorber was added excluding drometrisol in Example 1, the oil resistance, water resistance, air permeability and moisture permeability were similar to those of Example 1, but the thermal adhesive strength was It was confirmed that the remarkably decreased.

In addition, the eco-friendliness of the food flexible packaging material manufactured according to the present invention did not contain impurities and did not show adhesiveness in the alkali dissociation and dispersibility test of the product subject to environmental labeling and certification standards (EL 103:2007) of the Ministry of Environment of Korea. . Therefore, a level of reusability has been achieved.

In addition, the food flexible packaging material manufactured according to the present invention can be safely used as a food packaging paper in accordance with the test standards of the processing materials of the standards and standards for the food code mechanism and container packaging of the Ministry of Food Safety and Security.

<Experimental Example 2>

The ultraviolet transmittance of the food flexible packaging materials prepared in Example 1 and Comparative Examples 1 to 5 was measured by the following method, and the results are shown in Table 5 below.

* Ultraviolet transmittance: According to Gretagmacbeth's Coloreye 7000A, the transmittance of ultraviolet rays having a wavelength of 360 nm is divided by the transmittance of visible rays having a wavelength of 700 nm.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 ultraviolet ray
Transmittance 0.4 0.5 0.5 0.45 0.9 0.6

Referring to Table 5, in the case of Comparative Example 4 in which drometrisol was not added, it was confirmed that the UV transmittance was the lowest, and in Comparative Example 1 in which calcium ferrocyanide, calcium sorbate, and calcium casein were not added, instead of a calcium compound. In Comparative Example 2 to which calcium carbonate was added and Comparative Example 3 to which sodium perborate and acetic acid were not added, it was confirmed that the UV transmittance was lower than that of Example 1.

Compared to Comparative Example 1 and Comparative Example 2, the UV transmittance of Comparative Example 3 was improved, which is thought to show a slight UV blocking effect of calcium ferrocyanide, calcium sorbate and calcium caseinate.

In addition, in the case of Comparative Example 5, in which homosalate was added instead of dromethrizol, it was confirmed that the ultraviolet rosewood effect was inferior compared to Example 1.

As described above, what has been described in the present invention is merely an example for a method for manufacturing a food flexible packaging material having excellent oil resistance, water resistance, moisture resistance and thermal bonding strength, and the present invention is not limited to the above embodiment, but may be implemented in a variety of different forms. The present embodiment is provided only to complete the disclosure of the present invention, and to fully inform the scope of the invention to those of ordinary skill in the art to which the present invention belongs, and the present invention is the scope of the claims. Is just defined by

Claims (8)

Preparing an inner layer composition and an outer layer composition;
Including the step of coextruding the prepared inner layer composition and outer layer composition,
The step of preparing the inner layer composition may include preparing a prepolymer by mixing polyol, dimethylol propionic acid (DMPA), N-methylpinolidone (NMP) solution, and isocyanate;
Neutralizing the prepolymer with a neutralizing agent diluted in an N-methylpinolidone (NMP) solution, adding distilled water to the neutralized prepolymer to disperse it, and then adding a chain extender to prepare a water-dispersible polyurethane;
Adding an acrylic monomer, a biodegradation catalyst, and an initiator to the water-dispersible polyurethane, followed by stirring to prepare a water-soluble acrylic polyurethane;
Including the step of adding a calcium-based compound, sodium perborate and acetic acid to the water-soluble acrylic polyurethane,
The step of preparing the outer layer composition is characterized in that it comprises the step of mixing polyolefin, ethylenediaminetetraacetic acid (EDTA), calcium lactate, metal stearic acid, and drometrisol,
The step of adding a calcium-based compound, sodium perborate and acetic acid to the water-soluble acrylic polyurethane
It characterized in that to add 2 to 6 parts by weight of a calcium-based compound, 1 to 2 parts by weight of sodium perborate, and 1 to 2 parts by weight of acetic acid, based on 92 to 96 parts by weight of the water-soluble acrylic polyurethane,
The acetic acid is an eco-friendly food flexible packaging material manufacturing method for plastic replacement, characterized in that by ionic bonding with the calcium cation dissociated from the calcium-based compound to form calcium acetate.
The method of claim 1,
The calcium-based compound is an eco-friendly food flexible packaging method for plastic replacement, characterized in that the mixture of calcium ferrocyanide, calcium sorbate and calcium casein.
The method of claim 1,
The metal stearic acid is an eco-friendly food lead for plastic replacement, characterized in that it contains at least one of iron (III) stearate, ferric hydroxystearate, or copper stearate (copper(II) stearate). Packaging material manufacturing method.
The method of claim 1,
The step of preparing the prepolymer is
Dissolving 15 to 25 parts by weight of polyol in a vacuum oven at 60 to 80° C. based on 100 parts by weight of the prepolymer, then replacing the internal air with nitrogen and stirring;
Stirring by adding 15 to 25 parts by weight of dimethylolpropionic acid based on 100 parts by weight of the prepolymer; And
Replacing a plastic comprising: adding 1 to 5 parts by weight of an N-methylpinolidone (NMP) solution and 50 to 65 parts by weight of an isocyanate and reducing the temperature to 50° C. based on 100 parts by weight of the prepolymer. Manufacturing method of flexible packaging material for eco-friendly food.
The method of claim 1,
In the preparing of the water-dispersible polyurethane, 2 to 6 parts by weight of a neutralizing agent are mixed with 25 to 45 parts by weight of the prepolymer and 1 to 3 parts by weight of the N-methylpinolidone (NMP) solution based on 100 parts by weight of the water-dispersible polyurethane. To neutralize the prepolymer;
Stirring while adding 40 to 60 parts by weight of distilled water dropwise; And
5 to 15 parts by weight of a chain extender and a method of manufacturing a flexible packaging material for eco-friendly food for plastic replacement, comprising the step of stirring.
The method of claim 1,
The step of preparing the water-soluble acrylic polyurethane
The water-dispersible polyurethane based on 100 parts by weight of water-soluble acrylic polyurethane
70 to 85 parts by weight, 10 to 25 parts by weight of acrylic monomer, 1 to 3 parts by weight of biodegradation catalyst, and 1 to 3 parts by weight of initiator are added and stirred.
The method of claim 1,
The polyol is polytetramehtyleneglycol (PTMG), the isocyanate is isophorone diisocyanate (IPDI), the neutralizing agent is triethylamine (TEA), and the chain extender is ethylenediamine ( ethylene diamine, EDA), the acrylic monomer is methyl methacrylate (MMA), the biodegradation catalyst is ferric acetyl carbamate, the initiator is azobisisobutyronitrile (2,2'-azobis isobutyronitrile, AIBN), and the metal stearic acid is iron (III) stearate.
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