KR102220488B1 - eco friendly vessel for packing food - Google Patents

Abstract

The present invention relates to an eco-friendly disposable container for packing food and, more specifically, to an eco-friendly disposable container for packing food, which is for food packing and is made of pulp and a biodegradable coating material. The eco-friendly disposable container for packing food comprises: a container body having an accommodation space for accommodating food, and made of a biodegradable natural material; and a coating layer formed by applying a coating agent to the inner or outer surface of the container body. The coating agent is synthesized by mixing polyol, dimethylol propionic acid, isophorone diisocyanate, triethylamine, ethylene diamine, and water.

Description

Eco friendly vessel for packing food}

The present invention relates to an eco-friendly disposable container for food packaging, and more particularly, to an eco-friendly disposable container for food packaging made of a coating material capable of biodegradation with pulp while being suitable for food packaging.

The use of disposable containers for packaging various foods such as ramen, pizza, hamburgers, etc. is rapidly increasing due to the convenience of life.

These containers are thrown away in the natural world after use and do not decompose and contaminate the environment, which is a big social problem, and a countermeasure is urgently requested.

Disposable containers made of synthetic resin-based biodegradable materials such as starch, modified starch, natural polymer-based biodegradable materials such as starch and modified starch containing cellulose-based vegetable fibers, polylactic acid, aliphatic polyester, biodegradable polyurethane Has been studied.

In particular, natural polymer-based biodegradable materials centered on starch, etc., have been developed more widely because they are considered suitable for disposable products due to their great advantage of being very cheap compared to synthetic resin-based biodegradable materials.

However, the disposable container made of such a natural polymer biodegradable material is very vulnerable to moisture and gas barrier properties compared to conventional plastics, so there is a problem in preservation such as food leakage to the outside.

In order to solve this problem, Korean Patent Registration No. 10-0548949 discloses a method of attaching a film made of a synthetic resin-based biodegradable material to the inner surface of a container made of a natural polymer-based biodegradable material such as pulp fiber powder and starch.

However, there is a problem in that the film attaching process is difficult when the shape of the container is complicated because the above container has to be attached with a film inside.

In Korean Patent Registration No. 10-0574547, cellulose fibers and molten pulp fibers are pulverized and then mixed and molded with fiber powder treated with an acrylate copolymer, so that natural polymers are dispersed in the matrix of fiber powder coated with acrylate copolymer. A method of obtaining a biodegradable molded article having been disclosed is disclosed.

The biodegradable molded article has excellent biodegradability, but has a high manufacturing cost and low moisture barrier properties.

1. Korean Patent Registration No. 10-0548949: Biodegradable starch container and its manufacturing method 2. Korean Patent Registration No. 10-0574547: Biodegradable composition with improved water resistance and its manufacturing method

The present invention was created to improve the above problems, and it is an object of the present invention to provide an eco-friendly disposable container for food packaging that is made of a coating material that is biodegradable with pulp while being suitable for packaging various soups because food does not ooze out. .

An eco-friendly disposable container for packaging food of the present invention for achieving the above object includes: a container body formed of a biodegradable natural material having a storage space capable of accommodating food; And a coating layer formed by coating a coating agent on the inner or outer surface of the container body, and the coating agent is polyol, dimethylol propionic acid, isophorone diisocyanate, triethylamine ), ethylene diamine, and water are mixed.

As the polyol, polycaprolactonediol (PCL) and polyether polyol are used together in a weight ratio of 1: 0.5 to 2.

In order to improve the barrier property of the coating layer, cellulose nanofibers and starfish powder are added to the coating agent.

delete

As described above, the present invention has excellent barrier properties for moisture, oil, and various seasonings, so that food does not ooze out, so that it is suitable for packaging various soups and foods, but is made of a coating material that can be biodegradable with pulp. Can provide.

The disposable container of the present invention can be usefully used for various purposes such as delivery, storage, storage of food.

1 is a cross-sectional view of an eco-friendly disposable container according to an example of the present invention,
2 is a cross-sectional view showing a main part of an eco-friendly disposable container according to another example of the present invention,
3 is a cross-sectional view showing a main part of an eco-friendly disposable container according to another example of the present invention,
4 is a cross-sectional view showing a part of the photocatalytic ball applied to FIG. 3.

Hereinafter, an eco-friendly disposable container for food packaging according to a preferred embodiment of the present invention will be described in detail.

Referring to Figure 1, the eco-friendly disposable container 10 of the present invention is made of a container body 11, and a coating layer 13 formed on the inner or outer surface of the container body (11).

The container body 11 is formed of a container structure with an open upper portion and a space for accommodating food. It goes without saying that the size and shape of the container body 11 can be formed in various ways.

A packaging film 5 is attached to the open upper part of the container body 11. The packaging film 5 may be heat-sealed and attached to the upper edge of the container body 11. As the packaging film 5, a film made of a conventional synthetic resin material is used.

The container body 11 may be formed of a variety of materials, but is preferably formed of a natural material capable of biodegradation. For example, it is possible to mold the container body 11 using starch or pulp. The container body 11 made of this material can be naturally decomposed in the soil.

The container body 11 formed of natural materials such as starch or pulp has poor barrier properties. Accordingly, the present invention can prevent moisture, oil, and various seasonings from oozing out by forming a coating layer 13 on the inner or outer surface of the container body 11 to strengthen the barrier properties of the container body 11. have.

The coating layer 13 may be formed on the inner side or the outer side of the container body 13. In the illustrated example, the coating layer 13 is formed on the inner surface of the container body 11.

A water-dispersible polyurethane may be used as a coating agent for forming the coating layer 13. Such coating agents include polyol, dimethylol propionic acid (DMPA), isophorone diisocyanate (IPDI), triethylamine (TEA), ethylene diamine (EDA), and water. Can be synthesized.

For example, the coating agent is polyol 10 to 20% by weight, dimethylol propionic acid 2 to 4% by weight, isophorone diisocyanate 4 to 10% by weight, triethylamine 1 to 3% by weight, ethylene diamine 0.5 to 2% by weight, water 60 to It can be synthesized by mixing 80% by weight.

Polyol reacts with isocyanate to produce polyurethane.

Typical water-dispersible polyurethanes are polyols, among which polytetramethylene glycol (PTMG) or polycarbonate diol (PCD), polypropylene glycol (PPG), or polycaprolactonediol (PCL). Use either.

On the other hand, in the present invention, polycaprolactonediol (PCL) and polyether polyol are used together in a weight ratio of 1: 0.5-2 as a polyol. Polyether polyol improves the biodegradability of the coating layer.

Dimethylol propionic acid (DMPA) is an ionizing agent, and it introduces a hydrophilic group to improve hydrolysis resistance when synthesizing a coating agent.

Isophorone diisocyanate (IPDI) reacts with polyols to produce polyurethane. In addition, as the isocyanate, any one of diphenyl methanediisocyanate, hexamethylene diisocyanate, and dicyclohexylmethane diisocyanate may be used.

Triethylamine (TEA) is used as a neutralizing agent and acts to neutralize the prepolymer. In addition, trimethylamine (TMA) may be used as a neutralizing agent.

Ethylene diamine (EDA) is used as a chain extender. In addition, as a chain extender, any one of 1,4-butanediol, 1,6-hexane diol, ethylene glycol, and diethylene glycol You can use

Water acts to emulsify the prepolymer, and the amount of water is preferably 60 to 80% by weight, but may be appropriately adjusted as necessary.

It goes without saying that conventional additives such as emulsifiers, thickeners, and catalysts may be additionally used on the above materials.

In order to synthesize the coating agent, first, dimethylol propionic acid, an ionizing agent, is added to a polyol in which polycaprolactonediol and polyether polyol are mixed in a weight ratio of 1: 0.5 to 2, and the temperature is raised to 70 to 90°C while stirring.

Next, isophorone diisocyanate is added and reacted at 90° C. for 3 to 5 hours to cool the resulting prepolymer to room temperature.

Next, triethylamine, a neutralizing agent, was added to the prepolymer cooled to room temperature, followed by stirring for 20 to 40 minutes.

Next, after adding ethylene diamine and water as a chain extender, the mixture is stirred for 40 to 60 minutes to obtain a water-dispersible polyurethane coating. If necessary, the water-dispersible polyurethane may be distilled under reduced pressure at a pressure of 20 to 150 mmHg to remove the organic solvent.

The coating agent can form a coating layer by various coating methods. In addition to coating coating with a brush, various methods such as spray coating, spin coating, and immersion coating can be applied.

Meanwhile, in order to improve the barrier property of the coating layer, cellulose nanofibers and starfish powder may be further added to the coating agent. For example, 6 to 10 parts by weight of cellulose nanofibers and 1 to 5 parts by weight of starfish powder may be added to 100 parts by weight of water-dispersible polyurethane to obtain a coating agent.

Cellulose nanofibers refer to nano- or micrometer-sized rod-shaped particles or fibers in which cellulose chains are bundled together in a bundle. Cellulose nanofibers may have a diameter of 5 to 100 nm and a length of 10 to 100 μm. Cellulose nanofibers improve the strength, adhesion, and barrier properties of the coating layer.

Starfish powder means pulverized starfish into fine particles fired at high temperature (700~900℃). Starfish powder has a porous structure in which countless pores are formed on the surface and inside. Starfish powder having such a porous structure greatly improves the barrier property.

The above-described present invention has excellent barrier properties and does not ooze out of food, so it is suitable for packaging various soups and foods, and is made of a coating agent capable of biodegradation with pulp, thereby providing an eco-friendly disposable container for food packaging. These disposable containers can be usefully used for various purposes such as delivery, storage, storage of food.

On the other hand, in the present invention, as shown in FIG. 2, coating layers 13 and 15 may be formed on the inner and outer surfaces of the container body 11, respectively. In addition, although not shown, of course, the coating layer may be formed only on the outer surface of the container body.

delete

delete

delete

delete

delete

delete

delete

delete

delete

delete

delete

delete

delete

Hereinafter, the present invention will be described through the following examples. However, the following examples are intended to specifically illustrate the present invention, and are not intended to limit the scope of the present invention to the following examples.

(Example 1)

Polycaprolactonediol (Mw=2000) and polyether polyol (Mw=2000) were added to 15% by weight of polyol mixed at a weight ratio of 1:1, and 3% by weight of dimethylol propionic acid was added to the flask, and the temperature was stirred at 90°C. Put up. Then, 7 wt% of isophorone diisocyanate was added and reacted at 90° C. for 4 hours to produce a prepolymer, and then cooled to room temperature. And after adding 2% by weight of triethylamine to the resulting prepolymer, the mixture was stirred for 30 minutes. Then, 1% by weight of ethylene diamine and 72% by weight of distilled water were added, stirred for 50 minutes, and then aged for 30 minutes to synthesize a water-dispersible polyurethane coating.

A coating layer was formed by applying a coating agent to the inner side of the pulp container. The container in which the coating layer was formed was used as Sample 1.

(Example 2)

To 100 parts by weight of the water-dispersible polyurethane obtained in Example 1, 8 parts by weight of cellulose nanofibers and 4 parts by weight of starfish powder calcined and pulverized at 900° C. were added to apply a coating agent to the inner surface of the pulp material container to form a coating layer. Formed. The container in which the coating layer was formed was used as Sample 2.

(Comparative example)

A pulp container without coating was used as Sample 3.

<Food storage experiment>

Samples 1-3 were tested to see if food oozes out of the container. After containing 60 g of cooked seasoned pork belly in the container of each sample, the outer surface of the container was observed after 10 hours.

The experimental results are shown in FIGS. 5 to 7 respectively. 5 is a result of Sample 1, FIG. 6 is a result of Sample 2, and FIG. 7 is a result of Sample 3.

Referring to the experimental results, it was confirmed that in the case of the uncoated Sample 3, the red seasoning spread out widely and oozing out of the container and turning the container red. Pulp-based containers have the advantage of being biodegradable, but uncoated pulp-based containers are not suitable for packaging food.

In the case of Sample 1, the appearance of the container stained slightly red in several places was found, but compared to Sample 3, the amount of oozing out of the container was significantly reduced. Considering that the storage time of food is 10 hours in the experiment, Sample 1 will be suitable as a disposable container for food packaging when food is consumed in a shorter time than that.

In the case of Sample 2, the appearance of red oozing out of the container was hardly observed. Therefore, it was confirmed that the barrier property of Sample 2 was the best.

Through the above-described experimental results, the present invention is shown to have an effect of blocking moisture, oil, etc. contained in food, thereby providing an eco-friendly disposable container for food packaging.

In the above, the present invention has been described with reference to an exemplary embodiment, but this is merely exemplary, and those of ordinary skill in the art will appreciate that various modifications and equivalent embodiments are possible therefrom. Therefore, the true scope of protection of the present invention should be determined only by the appended claims.

5: packaging film 10: disposable container
11: container body 13: coating layer
16: antibacterial layer

Claims (4)

A container body formed of a natural material capable of being biodegradable and having a space for receiving food;
A coating layer formed by coating a coating agent on the inner or outer surface of the container body; and,
The coating agent is synthesized by mixing polyol, dimethylol propionic acid, isophorone diisocyanate, triethylamine, ethylene diamine, and water,
Eco-friendly disposable container for food packaging, characterized in that cellulose nanofibers and starfish powder are added to the coating agent in order to improve the barrier property of the coating layer. The eco-friendly disposable container for food packaging according to claim 1, wherein polycaprolactonediol (PCL) and polyether polyol are used together in a weight ratio of 1: 0.5-2 as the polyol. delete delete

Images