KR102667896B1 - Article for food container and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a molded body for a food container containing porous ceramic powder and synthetic resin and a plurality of micro-sized pores, and a method for manufacturing the same.

Description

Molded body for food container and method for manufacturing same {ARTICLE FOR FOOD CONTAINER AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a molded body for a food container and a method of manufacturing the same. The present invention relates to a molded body for a food container and a method of manufacturing the same that do not emit food odor even when food is stored for a long time or the food is repeatedly preserved and washed. .

For temporary or long-term storage of food, use food containers to block contact with external air.

A food container may have a concave bowl in which food is stored and a lid that can be opened and closed thereon. Such food containers allow food to be divided into a certain amount and stored, and food can be moved and stored without flowing or leaking.

When food is stored in a container, the food can spoil due to the introduction of external bacteria, foreign substances can easily enter, and rancidity can occur due to contact with oxygen, so it is manufactured as a sealable container.

On the other hand, since food has a unique odor due to water, oil, spices, and various ingredients, there may be a problem of the odor permeating into the container itself when in contact with the container, which reduces repeated usability or causes the user to Problems that may cause discomfort may arise.

Republic of Korea Patent Publication No. 2020-0130010 discloses a deodorizing composition containing a porous mineral impregnated with an odor-decomposing catalyst and a food storage container containing the same, comprising: metallic stearic acid; sodium-based compounds; and a deodorizing composition comprising a porous mineral impregnated with an odor-decomposing catalyst catalyst containing a metal oxide, and a food storage container manufactured using the same.

In addition, there is a problem in that fruits ripen more quickly due to ethylene gas generated as the fruits ripen, which further accelerates this process and causes rotting of the fruits. To solve this problem, removal agents that adsorb and remove ethylene gas are being developed, and containers that have the effect of adsorbing ethylene gas, such as disposable fruit packaging materials, are being developed.

Republic of Korea Patent No. 0490665 relates to a method of manufacturing an oxidation catalyst for ethylene gas removal. Oxidation for ethylene gas removal can effectively remove ethylene gas generated during storage of fruits and vegetables such as vegetables and fruits, thereby prolonging the freshness of fruits and vegetables. This relates to a method of manufacturing catalyst materials. Transition metals are used to effectively remove ethylene gas and odorous gases that are generated during the ripening process of vegetables or fruits while they are stored, which accelerates self-aging and induces early deterioration, thereby reducing product value. A method for producing a non-toxic inorganic oxidation catalyst containing oxides, noble metal components, and antibacterial components is disclosed.

To solve this problem, food containers made of various materials such as glass and ceramic have been released, but compared to existing plastic containers, they are heavier, more fragile, and can be damaged by rapid changes in temperature. There is a problem, and research to solve it is continuing.

Republic of Korea Patent Publication No. 2020-0130010 (2020.11.18) Republic of Korea Patent No. 0490665 (2005.05.11)

The purpose of the present invention is to provide a food container that has excellent airtightness and does not retain unnecessary odors, allowing for repeated use over a long period of time.

The purpose of the present invention is to provide a food container that is suitable for use in a microwave oven and is harmless to the human body even when containing hot food.

The purpose of the present invention is to provide a food container that has the effect of adsorbing ethylene gas inside, allowing the fruit to be stored in a fresh state for a long period of time.

The molded body for a food container according to the present invention to solve the above problems is composed of 10 to 25% by weight of porous ceramic powder with a size of 100 to 200 mesh and a porosity of 30 to 45%, polyethylene, and polypropylene ( It contains 75 to 90% by weight of at least one synthetic resin selected from the group consisting of polypropylene) and polyethylene terephthalate (PET, polyethylene telephthalate) and pores with a size of 5 to 10 μm (micrometer).

In the present invention, the porous ceramic powder may include metal on the inner surface of the pores.

More specifically, the metal may be included in an amount of 3 to 5% by weight based on the total weight of the porous ceramic powder.

The present invention also provides a method for manufacturing molded articles for food containers,

a) placing porous ceramic powder with a size of 100 to 200 mesh and a porosity of 30 to 45% in 95% ethanol and maintaining it for 30 to 1 hour, then taking it out and drying it;

b) storing the porous ceramic powder that has undergone step a) in a dryer maintained at a temperature of 40 to 50°C;

c) preparing a mixed dispersion by adding the porous powder that has gone through step b) into an aqueous metal ion solution and mixing it for 30 to 60 minutes at a speed of 10 to 20 rpm;

d) adding a metal ion reducing agent to the mixed dispersion obtained in step c), mixing and reacting at a speed of 10 to 20 rpm for 10 to 20 minutes, and then filtering the porous ceramic powder to obtain a filter;

e) preparing a melt by mixing the porous ceramic powder of step d) into a synthetic resin; and

f) manufacturing a molded body from the melt prepared in step e);

It provides a method of manufacturing a molded body for a food container comprising a.

In the production method according to the present invention, the metal ion aqueous solution in step c) has a metal ion concentration of 0.5 to 10% by weight, and in step d), the concentration of metal ions is 5 to 10 ㎛ (micro) during the reaction of the metal ion reducing agent in the mixed dispersion. meter) may be injected.

The food container according to the present invention has excellent airtightness and does not retain unnecessary odors, allowing repeated use for a long period of time.

The food container according to the present invention is suitable for use in a microwave oven and is harmless to the human body even if it contains hot food.

The food container according to the present invention has the effect of adsorbing ethylene gas inside, and has the effect of keeping the fruit fresh for a long period of time when storing it.

1 is a photograph of a food container according to an embodiment of the present invention.

Hereinafter, each configuration of the present invention will be described in more detail so that those skilled in the art can easily implement it. However, this is only an example, and the scope of rights of the present invention is determined by the following contents. Not limited.

As used herein, “preferred” or “preferably” refers to an embodiment of the invention that has certain advantages under certain conditions. However, other embodiments may also be preferred under the same or different conditions. Additionally, the identification of one or more preferred embodiments does not mean that other embodiments are not useful, nor does it exclude other embodiments that are within the scope of the invention.

As used herein, the term “comprising” is used to list materials, compositions, devices, and methods useful in the present invention and is not limited to the listed examples.

In particular, in the present invention, the term "comprising" refers to various states, such as a state in which the component is included as is, a state in which the component is processed as a precursor, a state in which the component is satisfied after processing, etc. It is not limited to the examples listed.

The molded body for a food container according to the present invention to solve the above problems is composed of 10 to 25% by weight of porous ceramic powder with a size of 100 to 200 mesh and a porosity of 30 to 45%, polyethylene, and polypropylene ( It contains 75 to 90% by weight of at least one synthetic resin selected from the group consisting of polypropylene) and polyethylene terephthalate (PET, polyethylene telephthalate) and pores with a size of 5 to 10 μm (micrometer).

The porous ceramic powder forms pores inside the molded body, and has a deodorizing and ethylene adsorption effect through the pores formed in the molded body itself.

Specifically, it is a porous ceramic particle having a porosity of 30 to 45%, and any ceramic particle having porosity can be used as long as it is harmless even when used in food containers.

Preferably, silica, zeolite, etc. can be used, and most preferably, zeolite can be used.

It is suitable that the size of the porous ceramic particles is 100 to 200 mesh, which is to ensure that the molten resin has fluidity for manufacturing into a molded body and to not increase the viscosity of the melt too much when mixed with the resin. .

If the viscosity of the melt increases, unnecessary defects may occur during extrusion molding, the rigidity of the container itself may decrease, and extrusion molding itself may become difficult and productivity may decrease.

The porous ceramic powder is preferably contained in an amount of 10 to 25% by weight. Even if it is contained in excess of the above amount, there is a problem that the viscosity of the melt increases when mixed with the molten resin, so it is added within the above range. desirable.

If it is added in a smaller amount than the above amount, there may be a problem of insignificant ethylene gas adsorption or deodorization effect.

The synthetic resin constituting the molded body of the present invention may include 75 to 90% by weight of at least one selected from the group consisting of polyethylene, polypropylene, and polyethylene telephthalate (PET).

It is a material that can be used in food containers for microwave ovens, etc., and may be composed of any one of the above materials or a mixture containing one or more of the above materials.

In the present invention, other additives other than the porous ceramic particles and synthetic resin are not specifically limited, but if necessary, other additives necessary for molding the container may be further included.

For example, pigments used to create color can be added in an amount of 5% by weight or less as long as they do not impair the function of the food container itself.

In the present invention, the porous ceramic powder may include metal on the inner surface of the pores.

The metal may be included as a discontinuous or continuous coating on the pores and external surfaces of the porous ceramic particles, and is discontinuously and thinly coated by microbubbles during manufacturing.

The metal may be included in an amount of 3 to 5% by weight based on the total weight of the porous ceramic powder. If it is added in excess of the above content, it may be unsuitable for use in a microwave oven, so it is preferable to use it within the above content range.

The metal is used to provide antibacterial functionality to the container, but when added in a smaller amount than the above amount, the antibacterial effect is minimal.

The metal may be any metal that has antibacterial properties, such as copper or silver, and most preferably contains copper and silver at a weight ratio of 7:1.

In addition, the molded body for a food container according to the present invention includes a plurality of pores with a size of 5 to 10 ㎛ (micrometers), which means that the porous ceramic particles contained in the molded body and the metal coating contained in the particles exhibit an antibacterial function. It is to do so.

In the manufacturing method to be described later, before extrusion molding the container, microbubbles with a size of 5 to 10 ㎛ (micrometer) are injected, the melt is mixed, and then extrusion molded, so that fine pores can be formed in the molded body.

The present invention also provides a method for manufacturing a molded body for a food container, which includes: a) placing porous ceramic powder with a size of 100 to 200 mesh and a porosity of 30 to 45% in 95% ethanol, maintaining it for 30 to 1 hour, then taking it out and drying it; b) storing the porous ceramic powder that has gone through step a) in a dryer maintained at a temperature of 40 to 50° C., c) putting the porous powder that has gone through step b) into an aqueous metal ion solution and heating it for 10 to 20 minutes. Preparing a mixed dispersion by mixing for 30 to 60 minutes at a speed of rpm, d) adding a metal ion reducing agent to the mixed dispersion obtained in step c) above, mixing at a speed of 10 to 20 rpm for 10 to 20 minutes to react, and then forming a porous mixture. Obtaining ceramic powder by filtering it; e) preparing a melt by mixing the porous ceramic powder of step d) with a synthetic resin; and f) manufacturing a molded body using the melt prepared in step e). It provides a method of manufacturing a molded body for a food container comprising:

Below, each step is described in more detail.

In step a), the porous ceramic powder is placed in 95% ethanol, maintained for 30 to 1 hour, then taken out and dried.

This is a step of degreasing the surface of the porous ceramic powder and the inside of the pores. Through this step, contact with the aqueous metal ion solution that proceeds later is facilitated, and as a result, a metal coating layer can be easily formed.

Next, step b) is a step of storing the porous ceramic powder that has gone through step a) in a dryer maintained at a temperature of 40 to 50°C, and is a process of drying the porous ceramic powder with minimal external contact. If the process is performed at a temperature higher than the above temperature, there is a problem in that the porous ceramic powder may become too dry and fine cracks may be formed.

Step c) is a step of preparing a mixed dispersion by placing the porous ceramic powder that has undergone step b) into an aqueous metal ion solution and mixing it for 30 to 60 minutes at a speed of 10 to 20 rpm, wherein the aqueous metal ion solution and the porous ceramic powder are sufficiently contacted. and mix sufficiently so that the metal ions diffuse into the internal pores of the porous ceramic powder.

At this time, the concentration of the metal ion aqueous solution may be 0.5 to 10%, preferably 3 to 8%.

Porous ceramic powder and aqueous metal ion solution can be reacted at a weight ratio of 1:1.

Step d) is a step of adding a metal ion reducing agent to the mixed dispersion obtained in step c), mixing and reacting at a speed of 10 to 20 rpm for 10 to 20 minutes, and then filtering the porous ceramic powder through a filter to obtain the reducing agent. The metal ions are reduced to form a discontinuous or continuous metal coating on the porous ceramic powder.

In step d), microbubbles of 5 to 10 μm (micrometer) are injected into the mixed dispersion during the reaction of the metal ion reducing agent.

The metal ion reducing agent may be added in an equivalent amount or more so that all metal ions can react.

Step e) is a step of preparing a melt by mixing the porous ceramic powder of step d) with a synthetic resin. Preferably, microbubbles of 5 to 10 ㎛ (micrometers) are slowly injected into the prepared melt. Afterwards, a mixing process can be additionally performed.

Step f) is a step of manufacturing a molded body from the melt prepared in step e), and can be manufactured by molding both the concave receiving part and the lid of the container with the melt.

Accordingly, the molded body can be manufactured as a receiving portion of a food container and/or a lid of a food container.

Hereinafter, the present invention will be described in more detail based on examples, but this is only an exemplary description for understanding the present invention, and the scope of the present invention is not limited or restricted to the following examples.

<Example 1>

15 parts by weight of zeolite (200 mesh, porosity 35%) was placed in 95% ethanol and left for 1 hour. Then, only the powder was separated and dried with wind at 25 to 30°C. This was maintained for 10 minutes in a dryer maintained at a temperature of 40 to 50°C.

Take it out, prepare an ionic aqueous solution (metal ion concentration 8%) containing copper ions and silver ions at a weight ratio of 7:1, add the previously prepared powder and mix for 40 minutes at a speed of 20 rpm to prepare a mixed dispersion. did. Here, ascorbic acid was added in an equivalent amount, microbubbles of 5 to 10 ㎛ (micrometer) were injected into the reaction solution, and the mixture was mixed at a speed of 20 rpm for 20 minutes to react. Only the solids were filtered out using a pressure reduction filter, and washed five times with purified water.

After melting the polypropylene resin, the prepared powder was added and thoroughly mixed, and then 5 to 10 ㎛ (micrometer) microbubbles were slowly injected and the melt was further mixed. Using this, extrusion molding was performed into the shape of a food container and lid (capacity 300 ml size).

<Comparative Example 1>

In Example 1, in the same manner as Example 1, except that microbubbles of 1 to 3 μm (micrometer) were injected into the reaction solution containing the mixed dispersion of the aqueous ionic solution and the zeolite and the addition of ascorbic acid. Manufactured.

<Comparative Example 2>

In Example 1, in the same manner as Example 1, except that microbubbles of 20 to 25 μm (micrometer) were injected into the reaction solution containing the mixed dispersion of the aqueous ionic solution and the zeolite and the addition of ascorbic acid. Manufactured.

<Comparative Example 3>

It was prepared in the same manner as Example 1, except that ultrasonic waves were applied to the reaction solution containing the mixed dispersion of the aqueous ionic solution and the zeolite and the addition of ascorbic acid.

<Reference example>

A commercially available microwave container made of PE of the same size was prepared.

[Experimental method]

1. Measurement of ethylene gas adsorption amount

- Test method: After placing each test sample in a sealed chamber, add 50 cc of ethylene gas (purity 95%) to a 1L container, keep it for 14 days, measure the remaining amount of ethylene gas, and measure the reduction rate (adsorption) before and after measurement. amount) is shown in the table below.

- Reduction rate (%)= [{(ethylene gas amount after experiment)-(ethylene gas amount before experiment)}/{ethylene gas amount before experiment}]* 100

Ethylene gas reduction rate (%) Example 1 79 Comparative Example 1 7 Comparative Example 2 12 Comparative Example 3 5 Reference example 4

2. Deodorizing effect test

- Test method: Prepare a container and lid for each test sample, and fill them with 10 cc of ammonia gas. After keeping it in the filled state for 14 days, all ammonia gas was removed, and then it was checked whether there was any odor remaining in the container.

Five testers were selected to perform the test, and after confirming whether they had a normal sense of smell, they were provided with the containers in which the experiment was completed and checked to see if there was any residual odor in each sample container. The test results are calculated based on when 4 or more people give the same evaluation, and if the same result is confirmed by less than 4 people, the same experiment is conducted again until 4 or more people show the same result. did.

- Evaluation method: No smell is felt (X), Ambiguous whether no smell is felt (△), Smell is felt (O)

Deodorizing effect test Example 1 X Comparative Example 1 △ Comparative Example 2 △ Comparative Example 3 O Reference example O

3. Antibacterial effect test

Each container was washed with detergent before the test, then wiped with alcohol to remove bacteria, and then the inside of the container was sterilized with an ultraviolet sterilizer, and then taken out of the sterilizer just before the test to conduct the experiment.

Thinly sliced apples (3cm*3cm*0.5cm) were placed in the prepared sample container, exposed to air without the lid, and kept for 18 hours. Afterwards, the apples inside the container were removed, the area where the bottom of the container meets the side wall was rubbed with a cotton swab 20 times, and the number of bacteria was measured to confirm the antibacterial effect.

The experiment was conducted using Staphylococcus aureus and Klebsiella pneumonia as strains, and the number of bacteria was measured and expressed as concentration after 18 hours.

Concentration after 18 hours (CFU/ml) control group Staphylococcus aureus 2.2 x 10 ⁴ pneumoniae 1.5 x 10 ⁶ Example 1 Staphylococcus aureus 5.1 x 10 ² pneumoniae 4.7 x 10 ² Comparative Example 1 Staphylococcus aureus 4.5 x 10 ⁴ pneumoniae 4.4 x 10 ⁴ Comparative Example 2 Staphylococcus aureus 3.7 x 10 ⁴ pneumoniae 3.2 x 10 ⁵ Comparative Example 3 Staphylococcus aureus 3.8 x 10 ⁴ pneumoniae 3.6 x 10 ⁵ Reference example Staphylococcus aureus 2.2 x 10 ⁴ pneumoniae 1.5 x 10 ⁶

4. Evaluation of suitability for use in microwave containers

A professional testing agency was asked to determine whether the container manufactured according to the example was suitable for use in a microwave oven, and the results are shown in the table below.

Material Type: Polypropylene Test, inspection items unit Test and inspection standards Test, inspection results Item judgment leaching lead mg/L 1 or less Not detected fitness Elution potassium permanganate consumption mg/L below 10 2 fitness Total elution amount: 4% acetic acid mg/L 30 or less One fitness Total amount of water eluted mg/L 30 or less 2 fitness Total elution amount n-heptane mg/L 150 or less 7 fitness Total judgment fitness Test, inspection method Food utensils and containers and packaging standards

Referring to Tables 1 to 4, it can be seen that the food container of the example has an ethylene gas adsorption effect, has the effect of keeping vegetables and fruits fresh, and can be kept fresh for a long period of time.

In addition, it can be confirmed that the container of the example has an excellent deodorizing effect compared to the comparative example or reference example. The container of the example can be used even after it has been used for a long period of time and multiple times to contain food, which has the effect of extending its useful life.

It can be confirmed that the container of the example not only has an antibacterial effect, but is also suitable for use in a microwave oven.

Therefore, the food container according to the present invention can keep fruits, etc. fresh for a long period of time, and has excellent antibacterial and deodorizing effects even when used for storing food, so it has an advantageous effect for long-term use, and can also be used for microwave ovens. This has possible effects.

Claims (5)

A method of manufacturing a molded body for a food container, comprising:
a) placing porous ceramic powder with a size of 100 to 200 mesh and a porosity of 30 to 45% in 95% ethanol and maintaining it for 30 to 1 hour, then taking it out and drying it;
b) storing the porous ceramic powder that has undergone step a) in a dryer maintained at a temperature of 40 to 50°C;
c) preparing a mixed dispersion by adding the porous powder that has gone through step b) into an aqueous metal ion solution and mixing it for 30 to 60 minutes at a speed of 10 to 20 rpm;
d) adding a metal ion reducing agent to the mixed dispersion obtained in step c), mixing and reacting at a speed of 10 to 20 rpm for 10 to 20 minutes, and then filtering the porous ceramic powder to obtain a filter;
e) preparing a melt by mixing the porous ceramic powder of step d) into a synthetic resin; and
f) manufacturing a molded body from the melt prepared in step e);
Including,
The synthetic resin is one or more selected from the group consisting of polyethylene, polypropylene, and polyethylene telephthalate (PET),
The molded body includes pores with a size of 5 to 10 μm (micrometer),
The metal ion aqueous solution in step c) is an aqueous solution containing copper ions and silver ions in a weight ratio of 7:1 and having a metal ion concentration of 3 to 8% by weight.
delete delete delete According to paragraph 1,
Step d) is a method of manufacturing a molded body for a food container, wherein microbubbles of 5 to 10 ㎛ (micrometer) are injected into the mixed dispersion during the reaction of the metal ion reducing agent.