KR20220094607A - Eco-friendly bio-degradable adhesive composition for food wrapping - Google Patents

Abstract

The present invention is an adhesive composition containing amino acids, dextrins, gums, and alkanediol, and a method for manufacturing the same, which has excellent adhesive strength and is capable of water separation and biodegradation, so that a substrate coated with the adhesive composition can be easily and completely removed from the adherend even in pure water that has not been treated with alkaline water, and thus when the adhesive composition of the present invention is applied to PP and PE packaging materials mainly used for food packaging materials, the adhesive composition is easily separated from the food packaging materials, and when released, it is safe for humans, animals, fish, and freshwater organisms, maintains a healthy natural ecosystem without toxicity and damage to soil, water quality, and green plants, and it is an environmentally friendly invention with no concerns of secondary environmental pollution.

Description

Eco-friendly bio-degradable adhesive composition for food wrapping

The present invention provides amino acids, It relates to an adhesive composition comprising dextrin, a gum and an alkanediol, and a method for preparing the same.

The food packaging sector accounts for more than 50% of the packaging market, and its growth is also steep. As the HMR market grows, the importance of advanced packaging technology is growing. As packaging expands to functional areas that can shorten cooking time or cook with microwaves, the demand for creative/innovative materials is also increasing. However, in the adhesive used for such packaging materials and containers, the components of the adhesive itself, components added during the manufacturing process, and hazardous components contaminated from the outside may exist in a mixture. In particular, most of these substances have a small molecular weight, so they can be transferred to food by reaction with food ingredients together with unreacted substances, monomers, oligomers, or reaction by-products during the manufacturing process. In case of excessive use, there is a risk that harmful substances of the adhesive may be excessively eluted. In addition, due to the increase in the use of microwave ovens or ovens due to changes in dietary habits that are becoming westernized, the transfer of harmful substances from adhesives to heated foods at high temperatures may be a problem.

Polyurethane is the main type of adhesive used in food packaging, and 60% of the adhesive is made up of polyurethane, and since fatty foods and heated foods require multi-layer packaging, the amount of polyurethane is inevitably increased. Polyurethane, a major component of food packaging adhesives, is a polymer of isocyanates and polyols, so primary aromatic amines can be induced from aromatic isocyanates, so isocyanates and amines are highly suspicious substances that can migrate to packaged foods. According to one study, isocyanates (2,6-toluene diisocyanate (2,6-TDI) and 2,4-toluene diisocyanate (2,4-TDI)) were 0.55-101.38 μg/mL in 10 of 26 packaging materials. was detected in a wide range of levels. The fact that a high concentration of toluene diisocyanate, a starting material for the synthesis of adhesives, was detected in large amounts compared to other packaging materials is that sufficient conditions for the polymerization of the adhesive components to react with water or alcohol components in the packaging material stacking process are not secured, so that the components remain. presumed to have been

These isocyanates and primary aromatic amines are well known as cancer-causing substances, so regulations are prepared in Europe. However, there is a limit to uniformly applying the proposed food regulations because the amount of toxic substances absorbed into food is different depending on the material, the type of packaged food, the heating temperature, etc. In addition, according to a study on potential harmful substances generated from packaging materials when cooking packaged food at about 100°C, such as in a microwave oven, when cooking convenience foods distributed in the market in a microwave, water boils. It has been reported that volatile organic compounds are generated at a certain temperature, and moisture generated during the cooking process becomes an important medium for heat transfer to the packaging film. When cooking with oily ingredients, a higher temperature may transfer to the film, and it is safe to wrap and refrigerate food with a low fat content, but when using in a microwave or using fatty foods, There are reports that there is a possibility that there will be more implementation.

In addition, petroleum-derived organic solvents are used during the manufacturing process in order to improve adhesion during the manufacturing of conventional adhesives, which impairs the health of workers and has environmental pollution problems in terms of environmental protection. In addition, most pressure-sensitive adhesives are difficult to decompose naturally because the monomer units are covalently bonded, and environmental pollution problems are also raised by polymers that have not been decomposed in this way. For this reason, various technologies for water-separable pressure-sensitive adhesives for effectively removing the pressure-sensitive adhesive from the adherend have been developed. In the conventional water-separable pressure-sensitive adhesive, high temperature and alkaline conditions are required to effectively remove the pressure-sensitive adhesive adhered to the adherend and the substrate, and additional energy resource consumption is required. In addition, when the pressure-sensitive adhesive material attached to the adherend or the substrate is removed by water separation, if the pressure-sensitive adhesive raw material molecules are discharged to the environment as they are, it may cause additional secondary environmental pollution problems. Therefore, a packaging material that has high adhesive strength, is harmless to the human body and does not cause environmental pollution is desired.

Patent Document 1: Patent Application No. 10-2016-0054206 Patent Document 2: Patent Application No. 10-2011-0029509

The present inventors are soluble in water, so there is no need to use harmful substances such as caustic soda when separated from the adherend. tried As a result, an adhesive composition in which an edible material such as dextrin is added to an amino acid that exists in the form of an aqueous salt solution and does not form a precipitate in the aqueous solution has been devised, and has excellent adhesion and water separation properties when applied to plastic labels mainly used for food packaging materials. The present invention was completed by increasing the water holding capacity of the soil and confirming the malodor adsorption effect.

Accordingly, an object of the present invention is an amino acid, An object of the present invention is to provide an eco-friendly adhesive composition comprising dextrin, gum and alkanediol as active ingredients and a method for preparing the same.

One aspect of the present invention for achieving the problem to be solved is an amino acid, Provided is an adhesive composition comprising dextrin, a gum, and an alkanediol.

In the present application, the term “adhesion” refers to a phenomenon in which two objects (except gas) are close to each other, and then a certain force (or work) is required to pull them off. In some cases, some materials having adhesion may be solidified after a certain period of time has elapsed after being applied to the substrate. In addition, the “adhesion” may include “viscoelasticity” that requires a certain amount of force for viscoelastic deformation when the adhesive material is separated from the substrate. The adhesive composition having viscoelastic properties is stored and distributed through a general processing form before being applied to a substrate, and its adhesion can be maintained even after a certain period of time has elapsed. The adhesive article obtained by applying and drying the adhesive composition on the substrate includes, for example, a label, an oriented polypropylene (OPP) tape, and the like. By using the adhesive properties, reversible attachment and detachment are possible, and when the adhesive composition is applied and dried on a substrate, an adhesive layer containing a viscoelastic material is formed on the substrate. All of the above substrates can be used as long as the adhesive composition can be applied to an adherend in the art. The substrate may be, for example, a polymer film. Polyolefin films such as polyethylene, polypropylene, tylene/propylene copolymer, polybutene-1, ethylene/vinyl acetate copolymer, polyethylene/styrene butadiene rubber mixture, polyvinyl chloride film, etc. may be used as the polymer film, for example. have. In addition, plastics such as polyethylene terephthalate, polycarbonate, and poly(methyl methacrylate), polyurethane, and thermoplastic elastomers such as polyamide-polyol copolymer, and mixtures thereof may be used.

The adhesive composition of the present invention has water-separability. Therefore, when the adhesive composition of the present invention is used as an adhesive, the adhesive is easily removed because it is dissociated by water when separated from or removed from the substrate or adherend to which the adhesive is applied. Specifically, the adhesive applied to the substrate or adherend may be dissociated within 1 hour, specifically within 30 minutes, and more specifically within 10 minutes using water at room temperature (25° C.) or higher. The adhesive composition of the present invention is environmentally friendly because it is easily dissociated with water and the dissociated component is also harmless to living things and the environment.

In one embodiment of the present invention, the adhesive composition is characterized in that the amino acid is present in the form of an aqueous salt solution and does not form a precipitate in the aqueous solution. When the adhesive composition maintains a liquid state without forming crystals or precipitation, it has excellent adhesion and is easy to apply uniformly to a substrate.

In one embodiment of the present invention, the amino acid is glycine, lysine or a mixture thereof. Specifically, it may be glycine.

In one embodiment of the present invention, the gum is selected from the group consisting of guar gum, locust bean gum, tara gum, konjac gum, konjac powder, fenugreek gum, mesquite gum, arabic gum, karaya gum, and xanthan gum any one or more Specifically, it may be xanthan gum.

In one embodiment of the present invention, the alkanediol is 1,2-hexanediol (1,2-hexanediol), 1,2-octanediol (1,2-octanediol), 1,2-decanediol (1,2 -decanediol), 1,6-hexanediol (1,6-hexanediol), any one selected from the group consisting of 1,8-octanediol (1,8-octanediol) and 1,3-butanediol (1,3-butanediol) more than one Specifically, it may be 1,2-hexanediol (1,2-hexanediol).

In one embodiment of the present invention, the adhesive composition comprises 0.1 to 50 parts by weight of amino acids, 0.01 to 10 parts by weight of gum, and 0.01 to 10 parts by weight of alkanediol based on 100 parts by weight of dextrin. Specifically, based on 100 parts by weight of dextrin, 10 to 30 parts by weight of amino acid, 0.1 to 5 parts by weight of gum, 0.1 to 7 parts by weight of alkanediol, and more specifically 20 parts by weight of amino acid, 1.5 parts by weight of gum, and 4.5 parts by weight of alkanediol includes wealth. In the above range, it has excellent viscosity stability with an average viscosity of about 50,000 CP, and has a high adhesive strength of about 222 gf/in or more on average. is appropriate as In addition, the food packaging material using the adhesive composition of the present invention is completely water-removed within a short time, and there is no biotoxicity, non-irritation, and excellent stability as a result of biotoxicity, soil contamination and skin irritation test results for the adhesive composition.

In one embodiment of the present invention, the pH of the adhesive composition is 2 to 11, specifically 2 to 9.5, more specifically 2 to 8.5. The adhesive composition having such a pH range has excellent storage stability and storage stability, and even if stored for a long time, there may be no change in formulation or quality. The adhesive composition has excellent adhesion and no precipitation even when used immediately after being prepared and used after long-term storage.

In one embodiment of the present invention, the curing speed may be increased by additionally including oil in the component. The oil may be coconut oil or palm oil, and the curing rate and adhesion of the adhesive may be improved by the addition of oil.

The adhesive composition or adhesive material of the present application may optionally include a reactive diluent, emulsifier, tackifier, plasticizer, filler, antioxidant, curing accelerator, flame retardant, coagulant, surfactant, thickener, sunscreen, elastomer, pigment, Dyes, fragrances, antistatic agents, antiblocking agents, slip agents, inorganic fillers, kneading agents, stabilizers, modified resins, coupling agents, leveling agents, optical brighteners, dispersants, heat stabilizers, light stabilizers, UV absorbers, waxes, wetting agents, oxidation agents and one or more additives selected from the group consisting of inhibitors, preservatives and lubricants. The total content of these additives is not particularly limited, and various additives may be included in various weight ranges depending on the intended use. The content of each of the additives listed above may be used at a level conventionally used in the art.

In one embodiment of the present invention, there is provided a food packaging material comprising the composition of the present invention.

According to another embodiment of the present invention,

S1) preparing an amino acid solution by stirring and mixing the amino acid in water;

S2) adding a gum to the prepared amino acid solution to increase the viscosity;

S3) adding an alkanediol to the mixed solution; and

S4) provides a method for preparing an adhesive composition comprising the step of adding dextrin to the solution.

In one embodiment of the present invention, the adhesive composition is characterized in that the amino acid is present in the form of an aqueous salt solution and does not form a precipitate in the aqueous solution.

In one embodiment of the present invention, the step S1) is characterized in that the solvent is first heated to 50 to 70 °C, and then amino acids are added and mixed with stirring until all are dissolved. When carried out outside the above temperature range, side reaction materials, impurities, etc. may be formed, and in some cases, it may be difficult to obtain an adhesive composition having a desired adhesive property.

In one embodiment of the present invention, the amino acid is glycine, lysine or a mixture thereof.

In one embodiment of the present invention, the gum is selected from the group consisting of guar gum, locust bean gum, tara gum, konjac gum, konjac powder, fenugreek gum, mesquite gum, arabic gum, karaya gum, and xanthan gum any one or more Specifically, xanthan gum.

In one embodiment of the present invention, the alkanediol is 1,2-hexanediol (1,2-hexanediol), 1,2-octanediol (1,2-octanediol), 1,2-decanediol (1,2 -decanediol), 1,6-hexanediol (1,6-hexanediol), any one selected from the group consisting of 1,8-octanediol (1,8-octanediol) and 1,3-butanediol (1,3-butanediol) more than one Specifically, it may be 1,2-hexanediol (1,2-hexanediol).

In one embodiment of the present invention, in the preparation method, based on 100 parts by weight of dextrin, 0.1 to 50 parts by weight of amino acid is mixed, 0.01 to 10 parts by weight of gum, and 0.01 to 10 parts by weight of alkanediol are mixed. Specifically, based on 100 parts by weight of dextrin, 10 to 30 parts by weight of amino acid, 0.1 to 5 parts by weight of gum, 0.1 to 7 parts by weight of alkanediol, and more specifically 20 parts by weight of amino acid, 1.5 parts by weight of gum, and 4.5 parts by weight of alkanediol includes wealth. In the case of the above range, it has excellent viscosity stability with an average viscosity of 50,000 CP, and has a high adhesive strength of about 200 gf/in or more on average, so it is suitable for adhesion to polyethylene (PE) and polypropylene (PP) packaging materials mainly used in food packaging materials. In addition, the food packaging material using the adhesive composition of the present invention is completely water-removed within a short time, and there is no biotoxicity, non-irritation, and excellent stability as a result of biotoxicity, soil contamination and skin irritation tests for the adhesive composition. Another aspect of the present invention comprises the steps of applying the adhesive composition to a first substrate to bond the adhesive composition to the first substrate; and contacting the first substrate to which the composition is bonded with the second substrate to attach the first substrate and the second substrate to each other; It provides a method of attaching a first substrate and a second substrate comprising a. In an embodiment of the present invention, the first substrate may be a PP, PE, PET, or PS substrate, and the second substrate may be PP, PE, PS, or PET.

In one embodiment of the present invention. The first substrate and the second substrate may be the same material. The adhesive composition or adhesive product according to an embodiment can be used as a water-removable adhesive for labels, adhesive tapes, spray-type adhesives, dust removers, etc., and can be easily removed using water without damaging the adherend, and is a packaging material can be easily recycled. And when this composition or product is applied to agricultural chemicals and seed fields, there is an advantage that it can be easily removed with water after using the adhesive-containing composition, so that the application range can be broadened.

The adhesive composition of the present invention described above uses an edible material as a raw material and is biodegradable when released and has high adhesive strength, and the substrate coated with the adhesive composition can be easily and completely removed from the adherend even in pure water that is not treated with alkaline water. When the adhesive composition of the present invention is applied to PP and PE packaging materials mainly used for food packaging materials, the recycling process is simplified as the separation of the adhesive composition from the food packaging material is easily achieved, and there is a concern of secondary environmental pollution when released It is an eco-friendly invention without

1 is a photograph of a sample used for biodegradation of the adhesive composition of the present invention;
2 is a photograph showing the skin administration range of the adhesive composition of the present invention used in the skin irritation experiment.
3 is a photograph of a skin irritation experiment of the present invention. 3a is a photograph of the skin 24 hours after application (initial test), 3b is a photograph of the skin 24 hours after application (confirmation test).
4 is a photograph of a skin irritation test of the present invention. 4a is a photograph of the skin 72 hours after application (initial test), 4b is a photograph of the skin 72 hours after application (confirmation test).

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. With reference to the accompanying drawings will be described in detail for the implementation of the present invention. Irrespective of the drawings, like reference numbers refer to like elements, and "and/or" includes each and every combination of one or more of the recited items.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

Hereinafter, an adhesive composition and a manufacturing method thereof according to embodiments of the present invention will be described.

[Preparation Example 1] Preparation of adhesive composition

A starch system was prepared using a wet blending method at the mixing ratio shown in Table 1 below. All of the glycine was dissolved while stirring in water heated from room temperature to 60° C. and used. When all of the glycine was dissolved into a transparent liquid, xanthan gum and 1,2-Hexanediol were added to prepare, and dextrin was added to prepare an adhesive composition. (Unit: parts by weight)

glycine dextrin xanthan gum 1,2-Hexanediol solvent (water) Example 15 100 2 4.5 80 Comparative Example 1 0.05 100 2 4.5 80 Comparative Example 2 15 100 2 0.005 80

[Experimental Example 1] Viscosity evaluation

The viscosity of the adhesive composition (Example) prepared by the above method was measured using a viscometer (manufacturer: TA instrument Std, trade name: DHR1) using a rotary rheometer at 25° C., 0.1 to 900 (1/s) shear rate conditions. did Table 2 shows the viscosity measured under the condition of 1 (1/s) shear rate.

Viscosity (cp) Example 50,000 CP

As a result, the Example of the present invention confirmed the viscosity of about 50,000CP, which was confirmed to be an appropriate level as an adhesive used for PP, PE, PET substrate.

[Experimental Example 2] Adhesion and light resistance evaluation

After the adhesive composition (Example) prepared by the above method was applied to a PP-PE specimen and adhered, the test was performed by repeating the frozen state and the room temperature state six times. After moving from freezing to room temperature, adhesion was checked after water condensation occurred on the outer surface of the PP-PE specimen, and it was confirmed that the adhesion was maintained regardless of temperature change. In the case of the food packaging material coated with Comparative Examples 1 and 2, it was confirmed that the packaging material was easily separated according to the temperature change, so that the adhesive force was not maintained.

In addition, a light resistance test (ASTM G 154) of the peel strength specimen was performed for quantitative evaluation of the adhesive force. Adhesion tests were performed on PE-PE, PE-PET, and PET-PET substrates. The substrate was manufactured to have a width of 2.5 x 10 cm and tested according to ASTM D 1876 at 60 ± 3 °C for 24 hours and 48 hours, respectively. The light resistance test device is Fluorescent UV/Condensation Weathering Instrument, UV Test Ⅱ W/Spray (ATLAS), the lamp is UV-A, 340nm, irradiance 0.89W/m ² *nm @ 340nm, and the total exposure time is 24 and 48h. to be.

The test was conducted under the conditions and methods above, and the results are shown in Table 3.

Adhesive name Adhesive type kgf/in gf/in Example PE-PE 0.222449 222.449 PE-PET 0.205102 205.102 PET-PET 0.222449 222.449 Comparative Example 1 PE-PE 0.114523 114.523 PE-PET 0.082345 82.345 PET-PET 0.146433 146.433 Comparative Example 2 PE-PE 0.093454 93.454 PE-PET 0.083453 83.453 PET-PET 0.095435 95.435

As a result, the adhesive composition (Example) was 220 gf / in at room temperature It showed the above adhesive strength, which is a high level of adhesive strength that can be peeled off only when a strong force is applied to the finger. Adhesion It was confirmed that the adhesive composition of Examples prepared by the present invention had higher adhesion than Comparative Examples 1 and 2.

[Experimental Example 3] Water separation test

Water separation properties of the adhesive composition (Example) and Comparative Example of the present invention were evaluated. The method for evaluating the water separation property is as follows: The adhesive composition of the present application was applied to a PP film and a PE film with a width of 50 to 60 μm and then attached to prepare a specimen.

After immersing the specimen in water, the time for the specimen to start separating and the time for complete separation were measured to evaluate the water separability. The evaluation results are shown in Table 4.

water separation start complete water separation Example Separation starts after 1 hour and 30 minutes Complete separation after 12 hours

In the same manner, a specimen was prepared, immersed in water, and shaken to measure the time for label separation and complete separation to measure water separation properties, and the evaluation results are shown in Table 5.

water separation start complete water separation Example 2 minutes 4 minutes

As a result, it was confirmed that the label separation was possible after 1 hour and 30 minutes in an environment without any external pressure after immersing the specimen (PP-PE) coated with the adhesive composition of the example in water. It was confirmed that water separation occurred.

[Experimental Example 4] Biodegradability

The biodegradability of the adhesive composition (Example) of the present invention was evaluated by requesting a FITI test researcher. The test method used is KS ISO 7827: 2018.

As a result of the experiment, it was confirmed that the biodegradability result of the present invention was 98.6% within 28 days.

[Experimental Example 5] Carp acute toxicity test

In order to evaluate the toxicity of the present invention, the test was conducted with reference to Chapter 3, Paragraph 3, 'Acute toxicity test for fish' in National Institute of Environmental Sciences Notice No. 2020-28 'Regulations on Test Methods for Chemicals'.

Specifically, 0.1 g of the adhesive composition (Example) of the present invention was put into a 1 L test container, and a set concentration of 100 mg/L test solution was prepared by filling the OECD algae medium up to the 1 L mark. Based on the preliminary test results, it was carried out for 96 hours in the control group and the experimental group (Example 100 mg/L). The total number of carp used in the test was 10 for each test group, and the total length of the carp was 3.4 ~ 4.0 cm, and the weight range was 0.41 ~ 0.71g. The water temperature was 24.0 to 24.1 °C, and the dissolved oxygen concentration was 81.9 to 97.2%. During the 96-hour exposure period, the pH of the control group and the experimental group (Example 100 mg/L) was 7.52 to 7.92. During the exposure period, toxicity symptoms were observed in the morning and afternoon at 24-hour intervals, and toxicity symptoms were checked for balance, swimming ability, breathing, and skin abnormalities. Meanwhile, during the test period, the control group maintained a transparent state until the end of the test, but in the experimental group, the color of the solution was transparent at first, but it was observed that the solution became cloudy from 24 hours. The test results are as follows.

division 0 hours 3 hours 5 hours 24 hours 48 hours 72 hours 96 hours number of lethal individuals control 0 0 0 0 0 0 0 experimental group 0 0 0 0 0 0 0 toxic reaction control normal normal normal normal normal normal normal experimental group normal normal normal normal normal normal normal

As a result of the test, no lethal subjects and no toxic symptoms were observed in the control group and the experimental group for 96 hours. The 48-hour and 96-hour hemi-lethal concentrations (LC ₅₀ ) of the present invention were both > 100 mg/L.

[Experimental Example 6] Daphnia acute toxicity test

In order to evaluate the toxicity of the present invention, the test was conducted with reference to Chapter 3, Paragraph 2 'Acute Toxicity Test for Water Fleas' in the National Institute of Environmental Sciences Notice No. 2020-28 'Regulations on Test Methods for Chemicals'.

Specifically, 0.1 g of the adhesive composition (Example) of the present invention was put into a 1 L test container and a set concentration of 100 mg/L test solution was prepared by filling the OECD algae medium up to the 1 L mark. Based on the preliminary test results, it was carried out for 48 hours in the control group and the experimental group (Example 100 mg/L). The experiment was repeated 4 times with 5 Daphnia magna in each test group. The water temperature was 20.0 ~ 20.1 °C, and the dissolved oxygen concentration was 5.75 ~ 8.57 mg/L. During the 96-hour exposure period, the pH of the control group and the experimental group (Example 100 mg/L) was 7.23 to 7.97. Swimming inhibition was observed at 24-hour intervals during the exposure period. Meanwhile, during the test period, the control group maintained a transparent state until the end of the test, but in the experimental group, the color of the solution was transparent at first, but it was observed that the solution became cloudy from 24 hours.

division 0 hours 24 hours 48 hours number of lethal individuals control 0 0 0 experimental group 0 0 0 toxic reaction control normal normal normal experimental group normal normal normal

As a result of the test, no lethal subjects and no toxic symptoms were observed in the control group and the experimental group for 96 hours. It was confirmed that the 48-hour half-water effect concentration (EC ₅₀ ) of the present invention was > 100 mg/L (Table 7).

[Experimental Example 7] Freshwater algae growth inhibition test

In order to evaluate the toxicity of the present invention, the test was conducted with reference to Chapter 3 Paragraph 1 'Freshwater Algae Growth Inhibition Test' in the National Institute of Environmental Sciences Notice No. 2020-28, 'Regulations on Test Methods for Chemicals'.

Specifically, 0.1 g of the adhesive composition (Example) of the present invention was put into a 1 L test container and a set concentration of 100 mg/L test solution was prepared by filling the OECD algae medium up to the 1 L mark. Freshwater algae (Pseudokirchneriella subcaoitata) for each test group was inoculated at an initial concentration of 5 × 10 ³ cell/ml, and based on the preliminary test results, the control group and the experimental group (Example 100 mg/L) were inoculated for 72 hours. The test was repeated 6 times. On the other hand, during the test period, both the control group and the experimental group maintained a transparent state at first, but from 48 hours on, as the algae grew, they took on a light green color. During the exposure period, the pH of the control group and the experimental group (Example 100 mg/L) was 7.23 to 8.15, and the range of change was -0.17 to -0.13, respectively. During the test period, the illuminance in the incubator was 5320 ~ 6640 Lux, and the temperature was kept constant at 22.5℃. The test results are as follows.

division Biomass (cell/ml) Exponential Growth Factor ¹⁾ yield ²⁾ Yield inhibition rate (%) ³⁾ Average specific rate of growth ⁴⁾ Specific growth rate inhibition rate (%) ⁵⁾ 0 hours 24 hours 48 hours 72 hours control Primary 5000 18800 98800 547500 109.5 542500 1.565 Secondary 5000 21300 100000 520000 104.0 515000 1.548 tertiary 5000 22500 101300 492500 98.5 487500 1.530 4th 5000 22500 101300 500000 100.0 495000 1.535 5th 5000 20000 98800 480000 96.0 475000 1.521 6th 5000 22500 100000 515000 103.0 510000 1.546 Average 5000 21267 10033 509167 101.8 504167 1.541 experimental group Primary 5000 22500 100000 488800 98.0 483800 -0.9 1.528 -0.2 Secondary 5000 16300 101300 508800 102.0 503800 1.541 tertiary 5000 23800 100000 528800 105.8 523800 1.554 4th 5000 18800 101300 548800 109.8 543800 1.566 5th 5000 22500 105000 470000 94.0 465000 1.514 6th 5000 21300 97500 537500 107.5 532500 1.559 Average 5000 20867 100850 513783 102.8 508783 1.544

1) exponential growth factor = 72 hour biomass / 0 hour biomass

2) Yield = 72 hour biomass - 0 hour biomass

3) Inhibition rate of yield = (control yield - experimental group yield)/control yield × 100

4) Average specific growth rate = In (72 hour biomass) - In (0 hour biomass) / 3 days

5) Inhibition rate of average specific growth rate = (Control group average specific growth rate - Experimental group average specific growth rate)/ Average specific growth rate × 100

As a result of the test, the average biological growth rate for 72 hours was 101.8 times in the control group and 102.8 times in the experimental group, the average specific growth rate inhibition rate of the experimental group was -0.2, and the yield inhibition rate was -0.9. Therefore, the 72-hour semi-water effect concentration (EC50) of the present invention was all > 100mg/L, confirming that there was no toxic effect on algae growth inhibition (Table 8).

[Experimental Example 8] Soil Pollution Degree

The degree of soil contamination of the adhesive composition (Example) of the present invention was evaluated by requesting the Korea Research Institute of Chemical Convergence. The experiment was conducted in accordance with the National Academy of Chemical Sciences Notice No. 2018-53: 2018 (Soil Pollution Process Test Standards). As a result of the experiment, it was confirmed that the present invention did not detect any of phenol, benzene, toluene, and mercury (Table 9).

The degree of soil contamination of the adhesive composition (Example) of the present invention was evaluated by requesting the Korea Research Institute of Chemical Convergence. The experiment was conducted in accordance with the National Academy of Chemical Sciences Notice No. 2018-53: 2018 (Soil Pollution Process Test Standards). As a result of the experiment, it was confirmed that the present invention did not detect any of phenol, benzene, toluene, and mercury (Table 9).

Test Items Results (mg/kg) phenol non-detection benzene non-detection toluene non-detection Mercury non-detection

[Experimental Example 9] Skin irritation test

In order to evaluate the acute skin irritation and corrosion of the adhesive composition (Example) of the present invention to Rabbit, the test substance was administered to the back for 4 hours and then mortality, general symptoms, weight change, and skin irritation and corrosion for 72 hours was evaluated. As test animals, Yac:NZW(KBL), Rabbit, SPF 3 month old males were used, of which 1 is for the initial test and 2 is for the confirmation test.

1) Test method

After hair removal [about (15 × 15) cm ² ] about 24 hours before administration of the test substance, one administration compartment with the width of [(2 × 3) cm ² ] was separated and marked immediately before administration (Fig. see 2). After attaching 0.5 mL of the test substance to the administration site, it was fixed using a non-irritating tape (Tegaderm, 3M) and an elastic bandage (Coban, 3M). The adjacent part other than the test substance administration site was used as a control site. After removing the patch of the test substance, the administration site was gently washed with a washing material (sterile distilled water).

First, as an initial test, three patches of test substance were sequentially administered to different sites for one experimental animal. The three test substance patches were applied for 3 minutes, 1 hour and 4 hours, respectively (skin irritation/corrosion test). Since no corrosiveness was observed until 4 hours of application during the initial test, a confirmation test was performed using two additional animals (skin irritation test). Each animal was exposed to one patch of test substance for 4 hours.

As for the skin reaction, in the case of the initial test, irritation and corrosion were observed after patch removal sequentially (3 minutes, 1 hour, 4 hours). Skin reactions were observed until 1, 24, 48 and 72 hours after patch removal for 4 hours. In the case of the confirmation test, skin reactions were observed up to 1, 24, 48 and 72 hours after patch removal for 4 hours.

The evaluation of the skin reaction was recorded by scoring the irritation according to the following table at 1, 24, 48 and 72 hours after the removal of the patch of the test substance, and the skin reaction mean score was calculated.

Erythema and crusting edema formation reaction Rating reaction Rating no erythema at all 0 no swelling at all 0 Very mild erythema (nearly discernible to the naked eye) One very mild swelling
(nearly discernible with the naked eye) One clear erythema 2 Mild edema (clear swelling to distinguish exposed areas) 2 Moderate to severe erythema 3 Moderate edema (in case of swelling of about 1 mm) 3 Severe erythema and erythema beyond evaluation 4 Severe swelling (swelling more than 1 mm and extending beyond the exposed area) 4

2) Experiment result

During the experimental period, no animal deaths or abnormal symptoms related to the administration of the test substance were observed.

As a result of body weight measurement, 72 hours after administration, the body weight was lower than the administration body weight. In addition, normal weight gain was observed in all animals.

As a result of observing the test substance administration site, irritation and corrosion were not observed in all animals (see FIGS. 3 to 4). Skin reaction mean score (Mean score) was calculated as "0.0" in all animals.

experimental object Erythema and crusting edema formation initial test 1101 0 0 confirmation test 1201 0 0 1202 0 0

From the above results, in the skin irritation and corrosion test for rabbits, the present invention did not cause skin irritation and corrosion, so it is not classified as a Hazard class in the classification according to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) confirmed to be

Claims (14)

amino acid, An adhesive composition comprising dextrin, a gum and an alkanediol. The adhesive composition according to claim 1, wherein the amino acid is present in the form of an aqueous salt solution and does not form a precipitate in the aqueous solution. The adhesive composition of claim 1, wherein the amino acid is glycine, lysine, or a mixture thereof. According to claim 1, wherein the gum is any one selected from the group consisting of guar gum, locust bean gum, tara gum, konjac gum, konjac powder, fenugreek gum, mesquite gum, arabic gum, karaya gum, and xanthan gum Adhesive composition of more than one. The method of claim 1, wherein the alkanediol is 1,2-hexanediol (1,2-hexanediol), 1,2-octanediol (1,2-octanediol), 1,2-decanediol (1,2-decanediol) ), 1,6-hexanediol (1,6-hexanediol), 1,8-octanediol (1,8-octanediol) and 1,3-butanediol (1,3-butanediol) at least one selected from the group consisting of adhesive composition. The adhesive composition of claim 1, wherein the adhesive composition comprises 0.1 to 50 parts by weight of amino acids, 0.01 to 10 parts by weight of gum, and 0.01 to 10 parts by weight of alkanediol based on 100 parts by weight of dextrin. A food packaging material comprising the adhesive composition according to any one of claims 1 to 6. S1) preparing an amino acid solution by stirring and mixing the amino acid in water;
S2) adding a gum to the prepared amino acid solution to increase the viscosity;
S3) adding an alkanediol to the mixed solution; and
S4) A method for preparing an adhesive composition comprising the step of adding dextrin to the solution. [Claim 9] The method of claim 8, wherein, in the adhesive composition, the amino acid is present in the form of an aqueous salt solution and does not form a precipitate in the aqueous solution. The method of claim 8, wherein in step S1), the solvent is first heated to 50 to 70° C., and then amino acids are added and mixed with stirring until all dissolved. The method of claim 8, wherein the amino acid is glycine, lysine, or a mixture thereof. The gum according to claim 8, wherein the gum is any one selected from the group consisting of guar gum, locust bean gum, tara gum, konjac gum, konjac powder, fenugreek gum, mesquite gum, arabic gum, karaya gum, and xanthan gum. Adhesive composition manufacturing method of the above. The method of claim 8, wherein the alkanediol is 1,2-hexanediol (1,2-hexanediol), 1,2-octanediol (1,2-octanediol), 1,2-decanediol (1,2-decanediol) ), 1,6-hexanediol (1,6-hexanediol), 1,8-octanediol (1,8-octanediol) and 1,3-butanediol (1,3-butanediol) at least one selected from the group consisting of A method for preparing an adhesive composition. The method according to claim 8, wherein, based on 100 parts by weight of dextrin, 0.1 to 50 parts by weight of an amino acid is mixed, 0.01 to 10 parts by weight of a gum, and 0.01 to 10 parts by weight of an alkanediol are mixed.

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