KR102458538B1 - Composition for producing food container having enhanced freshness maintenance property and preparing method of food container using the composition - Google Patents

Abstract

The present invention relates to a composition for manufacturing a food container excellent in freshness retention, including charcoal and volcanic stone, and a method for manufacturing a food container using the same. Specifically, the composition includes a master batch in which charcoal and volcanic stone are kneaded with a base resin, a polyolefin-based resin, a hollow filler, and a compatibilizer.

Description

Composition for manufacturing a food container with excellent freshness retention and a method for manufacturing a food container using the same

The present invention relates to a composition for manufacturing a food container excellent in freshness retention, including charcoal and volcanic stone, and a method for manufacturing a food container using the same.

Polyethylene, polypropylene, and polyethylene terephthalate, which are currently widely used thermoplastic resins, are inexpensive and have good processability, so they are widely used in household goods, packaging, and agricultural products.

In particular, the airtight container for storing food, such as vegetables, fruits, and food, which is used in conventional households, is mainly made of polypropylene. A food container made of such a material maintains the freshness of the food by preventing the escape of moisture from the inside. However, there is a problem in that it is not suitable for maintaining freshness for a long time because it blocks the inflow of air from the outside.

To overcome this, food containers are manufactured by mixing synthetic resins with known useful substances such as loess, elvan, jade, charcoal, etc., which are non-toxic, have high far-infrared emissivity and excellent deodorization and antibacterial activity, in an appropriate ratio to maintain the freshness of food. In addition, a technology for long-term preservation of food with antibacterial power has been developed.

However, in the above-mentioned mixed molded products, if more than an appropriate amount of inorganic materials such as loess, elvan, jade, and charcoal is mixed with respect to the synthetic resin, the moldability is poor and marketability is deteriorated. .

Accordingly, many prior application inventions and patented inventions limit the numerical value for the mixing ratio of synthetic resin and inorganic material, but in the process of implementation, the defect rate of the molded product is high, so it is inevitably limited to the minimum amount.

Korean Patent Registration No. 10-1001998

An object of the present invention is to provide a composition capable of manufacturing a food container with improved antibacterial and deodorizing ability, and a method for manufacturing a food container using the same.

An object of the present invention is to provide a composition capable of manufacturing a food container having excellent freshness retention and a method for manufacturing a food container using the same.

The object of the present invention is not limited to the object mentioned above. The objects of the present invention will become more apparent from the following description, and will be realized by means and combinations thereof described in the claims.

The composition for manufacturing a food container according to an embodiment of the present invention includes a master batch in which charcoal and volcanic stone are kneaded in a base resin, a polyolefin-based resin, a hollow filler, and a compatibilizer.

The base resin and the polyolefin-based resin include at least one selected from the group consisting of polypropylene (PP), low density polyethylene (LDPE), high density polyethylene (HDPE), and combinations thereof, respectively. can do.

The base resin and the polyolefin-based resin may each have a melt flow index of 10 g/10 min to 40 g/10 min (230° C., 2.16 kg).

The charcoal may be powdered to an average diameter of 13㎛ to 140㎛ and a particle uniformity of 70% or more.

The volcanic stone may be powdered to an average diameter of 13㎛ to 140㎛ and a particle uniformity of 70% or more.

The hollow filler has an average diameter of 5 μm to 70 μm, and may include spherical glass bubbles.

The compatibilizer may include a polypropylene grafted with maleic anhydride.

The composition comprises 40% to 55% by weight of the base resin, 40% to 55% by weight of the master batch, 1% to 5% by weight of the hollow filler, and 1% to 3% by weight of the compatibilizer, The master batch may include 0.1 wt% to 10 wt% of charcoal, 0.1 wt% to 10 wt% of volcanic stone, and the remainder of the polyolefin-based resin based on the total weight thereof.

The method of manufacturing a food container according to an embodiment of the present invention comprises the steps of pulverizing charcoal and volcanic stone, kneading and extruding the powdered charcoal and volcanic stone with a polyolefin-based resin to prepare a master batch, a base resin, a master batch, It includes the steps of processing the composition including the hollow filler and the compatibilizer into the extruder, and molding the processed resultant into the shape of a product.

The manufacturing method may be to irradiate and disperse powdered charcoal and volcanic stone with ultrasonic waves having a frequency of 200 kHz to 500 kHz for 30 minutes to 3 hours, followed by kneading and extrusion with a polyolefin-based resin.

The manufacturing method may be processing by further adding at least one additive selected from the group consisting of antioxidants, dispersants, pigments, and combinations thereof together with the composition to the extruder.

According to the present invention, it is possible to obtain a food container having excellent antibacterial properties by emitting negative ions and far-infrared rays.

According to the present invention, it is possible to obtain a food container having an excellent adsorption capacity with a porous structure and thus an excellent deodorizing effect.

According to the present invention, it is possible to obtain a food container capable of maintaining the freshness of the food therein compared to the conventional food container containing charcoal.

According to the present invention, it is possible to obtain a food container with a reduced defect rate by improving the weld line and the flow mark compared to the conventional food container containing charcoal.

The effects of the present invention are not limited to the above-mentioned effects. It should be understood that the effects of the present invention include all effects that can be inferred from the following description.

1 is a result of performing a freshness retention test using a food container according to Comparative Example 1.
2 is a result of performing a freshness retention test using a food container according to Comparative Example 2.
3 is a result of performing a freshness retention test using a food container according to Comparative Example 3.
4 is a result of performing a freshness retention test using the food container according to the embodiment.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed subject matter may be thorough and complete, and that the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In describing each figure, like reference numerals have been used for like elements. In the accompanying drawings, the dimensions of the structures are enlarged than the actual size for clarity of the present invention. Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. Also, when a part of a layer, film, region, plate, etc. is said to be “on” another part, this includes not only cases where it is “directly on” another part, but also cases where another part is in between. Conversely, when a part, such as a layer, film, region, plate, etc., is "under" another part, this includes not only cases where it is "directly under" another part, but also cases where there is another part in between.

Unless otherwise specified, all numbers, values, and/or expressions expressing quantities of ingredients, reaction conditions, polymer compositions and formulations used herein include, among other things, the numbers, values and/or expressions such that these numbers essentially occur in obtaining such values, among others. Since they are approximations reflecting various uncertainties in the measurement, it should be understood as being modified by the term "about" in all cases. Also, where numerical ranges are disclosed in the present description, such ranges are continuous and inclusive of all values from the minimum to the maximum inclusive of the range, unless otherwise indicated. Furthermore, when such ranges refer to integers, all integers inclusive from the minimum to the maximum inclusive are included, unless otherwise indicated.

The present invention relates to a composition for manufacturing a food container, wherein the composition includes a base resin, a master batch including charcoal and volcanic stone, a hollow filler, and a compatibilizer.

The base resin may include at least one selected from the group consisting of polypropylene (PP), low density polyethylene (LDPE), high density polyethylene (HDPE), and combinations thereof.

The base resin may have a melt flow index of 10 g/10 min to 40 g/10 min (230° C., 2.16 kg). If the melt index of the base resin is less than 10 g/10 min, moldability may deteriorate due to reduced flowability, and if it exceeds 40 g/10 min, impact strength may be reduced.

One feature of the present invention is to improve the antibacterial properties, deodorization effect, and freshness retention of food containers by adding charcoal and volcanic stone, and to make the charcoal and volcanic stone into a master batch so that they can be evenly dispersed in the food container. do it with

The master batch may be a polyolefin-based resin kneaded with charcoal and volcanic stone.

The polyolefin-based resin may be the same as or different from the base resin, and it may be preferable to use the same type in consideration of the miscibility of both resin components. The polyolefin-based resin may include at least one selected from the group consisting of polypropylene (PP), low density polyethylene (LDPE), high density polyethylene (HDPE), and combinations thereof.

The polyolefin-based resin may have a melt index of 10 g/10 min to 40 g/10 min (230° C., 2.16 kg). If the melt index of the polyolefin-based resin is less than 10 g/10 min, moldability may deteriorate due to reduced flowability, and if it exceeds 40 g/10 min, impact strength may be reduced.

The charcoal is a functional material such as inhibiting the generation of putrefactive bacteria, adsorbing polluting particles and odors, far-infrared and anion radiation, and preventing static electricity, and is used to impart the above functions and effects to food containers.

The charcoal may be powdered. Charcoal is a porous material, so as the temperature rises during molding (injection, extrusion, vacuum molding, pressurization, coating, etc.), the air in the pores expands and releases, and pinholes may occur. In order to prevent this, the present invention uses a powdered charcoal with an average diameter of 13 μm to 140 μm. When the average diameter of the charcoal exceeds 140 μm, the amount of air in the pores increases to generate pinholes, and accordingly, the quality of the food container may be deteriorated.

In addition, the char may have a particle uniformity of 70% or more, or 80% or more, or 90% or more. The particle uniformity is a measure of how even the average diameter of the charcoal particles is. The higher the particle uniformity, the more uniform the average diameter of the particles. When the average diameter of the charcoal is too different from each other, agglomeration of particles may occur, and thus mass productivity may be reduced. Therefore, the present invention uses the charcoal powder so that the particle uniformity is 70% or more.

Since the food container according to the present invention is thicker than the packaging material, it is difficult to exhibit antibacterial ability with a small amount of charcoal. However, if the content of charcoal is increased, a phenomenon of aggregation of activated carbon particles occurs, which leads to a decrease in antibacterial and deodorizing efficiency. In addition, if an excessive amount of charcoal is mixed with the polymer resin, weld lines and flow marks may occur on the molded product, resulting in deterioration of quality. Accordingly, the present invention is characterized in that by using charcoal and volcanic stone in combination, the content of charcoal is reduced and antibacterial properties and deodorizing effects are improved.

The volcanic stone is a natural mineral that emits negative ions and far-infrared rays, and has an excellent deodorizing effect with a porous structure.

The volcanic stone is not limited thereto, but may be, for example, Scoria. The scoria is a weakly alkaline porous material with a pH of about 9 to 10, and is a natural mineral material with a far-infrared emissivity of 90% or more, a deodorization rate of 95% or more, and an antibacterial performance of 99.9%.

The volcanic stone may be powdered. Since the volcanic stone is also a porous material, it may cause pinholes like the charcoal. Accordingly, the present invention uses a powdered volcanic stone having an average diameter of 13 μm to 140 μm. When the average diameter of the volcanic stone exceeds 140 μm, the amount of air in the pores increases to generate pinholes, and accordingly, the quality of the food container may be deteriorated.

In addition, the volcanic stone may have a particle uniformity of 70% or more, or 80% or more, or 90% or more. If the particle uniformity of the volcanic stone is less than 70%, agglomeration of the particles may occur, thereby reducing mass productivity.

The composition according to the invention is characterized in that it comprises a hollow filler. Charcoal is oriented in a specific direction when flowing with the polymer resin because of its irregular aspect ratio. This can cause quality problems such as weld lines on the appearance of injection molded parts. When a weld line is formed on a molded product, bacteria can propagate through the fine grooves and the contents can be easily damaged. Since the hollow filler is a round-shaped isotropic material, it may be positioned between a resin component such as a base resin and a polyethylene-based resin and the char to dilute the orientation of the char. In addition, the hollow filler may cause a ball-bearing effect to minimize the increase in viscosity of the composition according to its addition, and may help to reduce the weight of the food container.

In order to implement the above functions and effects, the present invention is characterized in that glass bubbles having an average diameter of 5 μm to 70 μm and spherical particles are used as the hollow filler.

The compatibilizer is intended to increase the miscibility of the above components, and is not limited thereto, but may include, for example, a polypropylene grafted with maleic anhydride.

The composition may include 40 wt% to 55 wt% of the base resin, 40 wt% to 55 wt% of the master batch, 1 wt% to 5 wt% of the hollow filler, and 1 wt% to 3 wt% of the compatibilizer have. In addition, the master batch may include 0.1 wt% to 10 wt% of charcoal, 0.1 wt% to 10 wt% of volcanic stone, and the remainder of the polyolefin-based resin based on the total weight thereof.

The composition may further include additives commonly used in the technical field to which the present invention pertains. For example, the additive may include at least one selected from the group consisting of antioxidants, dispersants, pigments, and combinations thereof.

The antioxidant may include at least one selected from the group consisting of phenolic antioxidants, phosphorus antioxidants, and combinations thereof.

The dispersing agent is intended to increase dispersibility during kneading of hydrophilic and lipophilic heterogeneous materials, and may include a processing aid having a functional group having an amphoteric structure, a melting point of 85°C to 120°C, and a decomposition temperature of 300°C or higher. For example, the dispersant may include calcium stearate, ethylene bis stearamide (EBS), plastaid-T from Fine Organics, and the like.

The input amount of the additive is not particularly limited, and an appropriate amount capable of exhibiting its function may be added.

The method for manufacturing a food container according to the present invention includes the steps of pulverizing charcoal and volcanic stone, kneading and extruding the powdered charcoal and volcanic stone with a polyolefin-based resin to prepare a master batch, base resin, master batch, hollow filler and commercialization It may include the step of processing the composition containing the agent into an extruder and molding the processed resultant into the shape of a product.

The description of each component has been described above, so it will be omitted below.

The powdering of the charcoal and volcanic stone may be performed by a method commonly used in the technical field to which the present invention pertains, and may be performed, for example, by a milling method.

In order to minimize the agglomeration of the powdered charcoal and volcanic stone, the powdered charcoal and volcanic stone are irradiated with ultrasonic waves and dispersed therein, and then kneaded and extruded with the polyolefin-based resin to prepare a master batch. Ultrasonic irradiation conditions are not particularly limited, but, for example, may be dispersed by irradiating ultrasonic waves having a frequency of 200 kHz to 500 kHz for 30 minutes to 3 hours.

The master batch may be prepared using a kneader or an extruder, and a compatibilizer, a dispersant, etc. may be added together to increase the dispersibility and surface adhesion of charcoal and volcanic stone in the polyolefin-based resin. .

Thereafter, the composition including the base resin, the master batch, the hollow filler and the compatibilizer may be added to the extruder and processed. At this time, in order to minimize deterioration of physical properties due to re-extrusion of the master batch, the master batch may be fed into the extruder through a side feeder. In addition, the composition may be processed by adding at least one additive selected from the group consisting of antioxidants, dispersants, pigments, and combinations thereof.

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. However, the present invention is not limited to Examples and Comparative Examples.

<Examples and Comparative Examples 1 to 3>

The components shown in Table 1 were put into the extruder at the indicated content and processed, and the processed product was molded into the shape of a food container.

ingredient Comparative Example 1 Comparative Example 2 Comparative Example 3 Example Base resin [wt%] 92 92 47 42 Charcoal [wt%] 5.0 - - - Volcanic stone [wt%] - 5.0 - - Masterbatch Containing Charcoal and Volcanic Stone [wt%] - - 50 50 Hollow filler [wt%] - - - 5 Compatibilizer [wt%] 3 3 3 3 Primary antioxidant [parts by weight] 0.2 0.2 0.2 0.2 Secondary antioxidant [parts by weight] 0.2 0.2 0.2 0.2 Pigment [parts by weight] 0.5 0.5 0.5 0.5 dispersant
[parts by weight] external lubricant 0.5 0.5 0.5 0.5 internal lubricant 0.5 0.5 0.5 0.5 Mah-g-dispersant One One One One

In Table 1, the base resin is polypropylene having a melt index of 28 g/10 min (230° C., 2.16 kg).

The charcoal is a charcoal powder having an average diameter of about 25 μm and a particle uniformity of 70% or more.

The volcanic stone is a volcanic stone powder having an average diameter of about 25 μm and a particle uniformity of 70% or more.

The master batch containing the charcoal and volcanic stone is that charcoal and volcanic stone are kneaded into a polypropylene resin, and the charcoal and volcanic stone are included in 10% by weight based on the total weight of the master batch, and the mixing ratio of the charcoal and volcanic stone is 1: 1 is Here, the charcoal has an average diameter of about 25 μm, a charcoal powder having a particle uniformity of 70% or more and an average diameter of about 25 μm, the volcanic stone is a volcanic stone powder having a particle uniformity of 70% or more, and the polypropylene resin has a melt index is 28 g/10 min (230° C., 2.16 kg) of polypropylene.

The hollow filler is a glass bubble, which is a hollow spherical particle having an average diameter of 30 μm to 39 μm.

The compatibilizer is a polypropylene resin grafted with maleic anhydride.

The primary antioxidant is a phenolic antioxidant, and Irganox 1010 manufactured by BASF was used.

The secondary antioxidant is a phosphorus antioxidant, and BASF's Irgafos 168 was used.

As the pigment, an inorganic pigment was used.

Calcium stearate S of FACI was used as the external lubricant. The internal lubricant was EBS (ethylene bis stearamide) and HI-LUBE of Shinwon Chemical was used. As the Mah-g-dispersant, Plastaid-T from Fine Organics was used.

The content of the primary antioxidant, secondary antioxidant, pigment and dispersant is based on 100 parts by weight of the base resin, charcoal and volcanic stone (comparative example), master batch (example), hollow filler, and compatibilizer ( parts by weight).

<Experimental example - freshness retention evaluation>

After putting lettuce into the food containers of Examples and Comparative Examples 1 to 3 and sealing it, the change in the freshness of the lettuce with the passage of time was visually observed.

1 is a result of Comparative Example 1, FIG. 2 is a result of Comparative Example 2, FIG. 3 is a result of Comparative Example 3, and FIG. 4 is a result of Example.

In the food container prepared by directly adding charcoal to the base resin without masterbatching through FIG. 1, lettuce went bad at the time of 2 days, and volcanic stone was added directly to the base resin without masterbatching through FIG. It can be seen that the lettuce went bad at the time of the lapse of 6 days in the food container manufactured by

Referring to FIG. 3 , although charcoal and volcanic stone were masterbatched, the food container prepared without adding glass bubbles maintained freshness longer than in the food containers of FIGS. 1 and 2 , but lettuce at the time of 8 days elapsed was offended

On the other hand, in the food container in which charcoal and volcanic stone were masterbatched and glass bubbles were added as in the present invention, lettuce did not go bad even after 8 days. As a result, it was confirmed that, according to the present invention, a food container having excellent freshness retention power can be obtained.

The scope of the present invention is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

Claims (11)

base resin;
a master batch in which charcoal and volcanic stone are kneaded into a polyolefin-based resin;
hollow filler; and
Compatibilizer; Including,
The composition comprises 40% to 55% by weight of the base resin, 40% to 55% by weight of the master batch, 1% to 5% by weight of the hollow filler, and 1% to 3% by weight of the compatibilizer,
The master batch is a composition for manufacturing a food container comprising 0.1% to 10% by weight of charcoal, 0.1% to 10% by weight of volcanic stone, and the remaining amount of polyolefin-based resin, based on the total weight. According to claim 1,
The base resin and the polyolefin-based resin include at least one selected from the group consisting of polypropylene (PP), low density polyethylene (LDPE), high density polyethylene (HDPE), and combinations thereof, respectively. A composition for manufacturing a food container. According to claim 1,
The base resin and the polyolefin-based resin each have a melt flow index of 10 g/10 min to 40 g/10 min (230° C., 2.16 kg) of a composition for manufacturing a food container. According to claim 1,
The charcoal is a composition for manufacturing a food container that is powdered to an average diameter of 13 μm to 140 μm and a particle uniformity of 70% or more. According to claim 1,
The volcanic stone is a composition for manufacturing a food container that is powdered to an average diameter of 13 μm to 140 μm and a particle uniformity of 70% or more. According to claim 1,
The hollow filler has an average diameter of 5 μm to 70 μm, and a composition for manufacturing a food container comprising glass bubbles having spherical particles. According to claim 1,
The compatibilizer is a composition for manufacturing a food container in which maleic anhydride is grafted to polypropylene. delete As a method for manufacturing a food container using the composition of any one of claims 1 to 7,
pulverizing charcoal and volcanic stone;
preparing a master batch by kneading and extruding powdered charcoal and volcanic stone with a polyolefin-based resin;
Processing a composition comprising a base resin, a master batch, a hollow filler and a compatibilizer into an extruder; and
A method of manufacturing a food container comprising; molding the processed result into the shape of a product. 10. The method of claim 9,
A method of manufacturing a food container in which powdered charcoal and volcanic stone are irradiated with ultrasonic waves having a frequency of 200 kHz to 500 kHz for 30 minutes to 3 hours and dispersed, and then kneaded and extruded with a polyolefin resin. 10. The method of claim 9,
A method of manufacturing a food container by further adding at least one additive selected from the group consisting of antioxidants, dispersants, pigments, and combinations thereof together with the composition to the extruder.

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