KR102030318B1 - Manufacturing method of pulp molded article and the pulp molded article by the same - Google Patents

Abstract

The present invention relates to a method for manufacturing a molded pulp having excellent strength, antimicrobial activity and gas adsorption capacity, and a molded pulp manufactured thereby, wherein the method comprises the steps of: pulverizing natural minerals; manufacturing a suspension of calcium carbonate and natural minerals having excellent dispersibility; manufacturing a pulp suspension in which calcium carbonate is evenly attached to the pulp surface; and manufacturing a molded pulp by molding and using the mixture of the suspension of natural minerals and calcium carbonate and the pulp suspension.

Description

Manufacturing method of pulp molded article having excellent antimicrobial performance and pulp molded article produced by the same {Manufacturing method of pulp molded article and the pulp molded article by the same}

The present invention relates to a method for producing a pulp molded article having excellent antibacterial performance and gas adsorption capacity and excellent strength, and a pulp molded product produced thereby.

Recently, due to the increasing interest in the food environment, consumers have been very interested in the safety and rationality of packaging for storage and distribution in the purchase of food or agricultural products. Therefore, many developments and growths have been made in related packaging technology and packaging materials.

In particular, packaging technology and packaging materials maintain the freshness of foods (which may be referred to as "food"), such as meat, fish, vegetables, fruits, processed foods, and prevent contamination from various harmful external environments for a certain period of time. It has been developed in the direction to do so. When food is stored, the freshness of the food decreases with time, and the corruption of the food cannot be avoided due to the growth of mold and bacteria. In particular, due to the increase of one-person households and the development of eating out culture, there is an increasing need to store foods for a long time, which causes a large amount of foods to be disposed of due to corruption.

On the other hand, during long-term storage and transportation of fruit and vegetables, they adsorb and remove ethylene gas and carbonic acid gas generated by respiration of fruit and vegetables, and maintain freshness of fruits and vegetables by preventing decay by microorganisms or by deodorization by delay and adsorption of ammonia. Along with the effect of extending the distribution and storage period, the purchase value of fruit and vegetable products is increased and only the fragrance remains, so that it is possible to stimulate the consumer's desire to purchase and improve the merchandise.

However, polymer resins such as polyethylene (PE), polypropylene (PP), and polyester (PET) used as raw materials are not only harmful to the environment but also harmful to the environment due to the addition of various chemical substances to satisfy physical properties. Elution may adversely affect the human body and environmental hormones are released during disposal. In addition, since it prevents moisture escape and external air inflow of food stored inside, it is possible to prevent freshness and decay in the short term, but it does not manage the decay and deterioration of food in the long term. There is a problem that remains and is delivered to the consumer.

On the other hand, agricultural products such as fresh foods, fruits and flowers are mainly packaged in cardboard boxes and distributed. Corrugated cardboard box protects the appearance of the product, but there is no function to maintain the freshness in the long-term distribution process, so fresh foods such as fruits and vegetables are reduced in freshness and shortened the distribution period. Most fruits and vegetables ripen over time. At this time, ethylene gas, a plant's aging hormone, is generated, which accelerates ripening and causes rancidity.

In order to solve this problem, Korean Patent Nos. 0788874 and 115857 have applied a coating agent containing zeolite and bentonite having hygroscopic and adsorptive properties to at least one side of a base paper (nonwoven fabric or paper) to improve the freshness of food. By providing a sustainable packaging material, it was intended to prevent the vegetables or fruits from wilting or deteriorating. However, the coating agent has low fluidity, very poor dispersibility, and problems such as clogging of the nozzle continuously occur during the manufacturing process.

In addition, the applicant of the present invention to prepare a coating liquid by mixing zeolite powder, diatomaceous earth powder, calcium carbonate powder, water and polylactic acid through Korea Patent Publication No. 1787910 and the coating liquid is a base paper (paper, fabric Or a non-woven fabric) has been proposed a method of manufacturing a food packaging material to be dried. However, the polylactic acid included in the food packaging material has a high heat shrinkage rate and low heat resistance, so that the packaging material may be deformed in the summer, and the impact resistance is low, and thus, it is easily broken by external force.

In addition, the use of recycled fibers in the production of pulp molded article is a drop in the physical properties of the pulp molded article, so that the thick paper to maintain a certain level of physical properties. As a result, as the weight of the packaging paper becomes heavier, the logistics cost is increased. Therefore, there is an urgent need for functional, pulp molded products that are light, strong, and more environmentally friendly.

In addition, even in precision instruments such as watches and cameras, damage to the product may be caused by a very small amount of harmful gases such as carbonic acid or ammonia generated from the inside of the packaging box. Therefore, it is necessary to develop a wrapping paper that can protect the precision machinery from the outside while adsorbing harmful gases to the precision machinery.

The present invention has been made to solve the above problems, preventing the growth of mold and bacteria in the distribution and sale of food, and the problem that the freshness is rapidly reduced by the ethylene gas generated in the process of food respiration of food. In order to solve the problem, not only can the adsorption and removal of biological over-causing substances such as ethylene gas, amine, ammonia, acetic acid, etc., but also the environmentally friendly pulp molding method of producing less pulp molding and less damage, and the pulp produced thereby It is to provide a molded body.

One embodiment of the present invention comprises the steps of grinding the particle size to 200 to 500 mesh for one or more natural minerals selected from the group consisting of zeolite, diatomaceous earth, elite, pozzolane and mixtures thereof; 10 to 30 parts by weight of calcium carbonate, 5 to 15 parts by weight of acrylate copolymer, 1 to 5 parts by weight of surfactant, and 500 to 1000 parts by weight of water are mixed with respect to 100 parts by weight of the natural minerals pulverized, thereby providing excellent dispersibility. Preparing a suspension of natural mineral and calcium carbonate; 1000 to 2000 parts by weight of water, 5 to 25 parts by weight of calcium carbonate, and 1 to 5% by weight with respect to 100 parts by weight of one or more pulp selected from the group consisting of coniferous pulp, hardwood pulp, highland pulp and mixtures thereof. 50 to 70 parts by weight of an aqueous calcium hydroxide solution and 0.1 to 2 parts by weight of citric acid are mixed and stirred, followed by carbonization by injecting CO ₂ gas, and further adding 5 to 15 parts by weight of a water-soluble polymer in the course of the carbonation. Preparing a pulp suspension evenly attached to the pulp surface; And molding a pulp molded body by molding the suspension using the suspension of the natural mineral and calcium carbonate and the pulp suspension in a ratio of 1: 5 to 10 by weight. to provide.

Preparing a suspension of the natural mineral and calcium carbonate; The calcium carbonate has an average particle diameter of 100 to 700 nm, the acrylate copolymer is an acrylate / acrylamide copolymer, acrylate / aceto acetoxy ethyl meth- acrylate copolymer and acrylate / C10-C30 alkyl It is one or more acrylate-based copolymers selected from the group consisting of acrylate crosslinking polymer, the surfactant may be a compound represented by the following formula (1).

[Formula 1]

In Formula 1, R ₁ is an alkyl group having 5 to 20 carbon atoms, R ₂ is an alkyl group having 1 to 10 carbon atoms, and X is 1 to 40.

Preparing the pulp suspension; The calcium carbonate has an average particle diameter of 1 to 100 nm, the water-soluble polymer may be a mixture of polymethacrylic acid (PMAA) and water-soluble cellulose in a 2: 1 weight ratio.

Another embodiment of the present invention provides a pulp molded body prepared by the method for producing a pulp molded body according to the embodiment of the present invention.

Method for producing a pulp molded article according to an embodiment of the present invention is excellent in antibacterial performance and gas adsorption capacity, there is an effect that can provide a pulp molded article excellent in strength.

More specifically, the pulp molded body according to one embodiment of the present invention exhibits strong antibacterial activity against microorganisms such as bacteria, molds and yeasts that cause decay and decay of contents, such as fruit and vegetables, to maintain freshness of contents such as fruits and vegetables for a long time. It has the effect of increasing the value of the product.

In addition, it has excellent gas adsorption ability to adsorb and remove fruit-causing substances such as ethylene gas, amine, ammonia, acetic acid, etc., and solves the problem that freshness is rapidly deteriorated by ethylene gas generated during the cellular respiration process of fresh food. It is very suitable as a packaging material for fresh food and / or precision appliances.

Furthermore, by solving the problem that the damage of the product can be caused by the harmful gas such as carbon dioxide or ammonia generated from the inside of the packaging box, there is a very suitable effect as a packaging material for precision machinery such as watches and cameras.

In addition, the pulp molded body according to one embodiment of the present invention has an excellent tensile strength.

1 shows a schematic image of a molding tank for producing pulp molded body according to an embodiment of the present invention.
2 and 3 is an image showing a comparison between the control piece and the pulp molded body prepared according to an embodiment of the present invention by inoculating bacteria, Figure 2 is pneumococcal, Figure 3 Salmonella inoculated 18 hours It is multiplying.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, by which the present invention is not limited and the present invention is defined only by the scope of the claims to be described later.

One embodiment of the present invention comprises the steps of grinding the particle size to 200 to 500 mesh for one or more natural minerals selected from the group consisting of zeolite, diatomaceous earth, elite, pozzolane and mixtures thereof; 10 to 30 parts by weight of calcium carbonate, 5 to 15 parts by weight of acrylate copolymer, 1 to 5 parts by weight of surfactant, and 500 to 1000 parts by weight of water are mixed with respect to 100 parts by weight of the pulverized natural mineral. Preparing a suspension of good natural mineral and calcium carbonate; 1000 to 2000 parts by weight of water, 5 to 25 parts by weight of calcium carbonate, and 1 to 5% by weight with respect to 100 parts by weight of one or more pulp selected from the group consisting of coniferous pulp, hardwood pulp, highland pulp and mixtures thereof. 50 to 70 parts by weight of an aqueous calcium hydroxide solution and 0.1 to 2 parts by weight of citric acid are mixed and stirred, followed by carbonization by injecting CO ₂ gas, and further adding 5 to 15 parts by weight of a water-soluble polymer in the course of the carbonation. Preparing a pulp suspension evenly attached to the pulp surface; And molding a pulp molded body by molding the suspension using the suspension of the natural mineral and calcium carbonate and the pulp suspension in a ratio of 1: 5 to 10 by weight. to provide.

As a result, by mold molding the natural mineral and calcium carbonate having excellent antimicrobial performance and gas adsorption ability and evenly suspended on the pulp, the antimicrobial performance and the gas adsorption performance of the finally produced pulp molded body are remarkably improved. Strength can also be greatly improved.

Natural minerals according to the present invention have excellent water absorption and adsorption of heavy metals such as ethylene gas, amine, ammonia, acetic acid and the like due to the numerous features of the pores of the open cells and the structural features of the large surface area of the inner space. It works. Such natural minerals may be used together with those generally used in the art.

The natural minerals are described in more detail as follows.

The zeolite is an aluminum silicate mineral of porous crystals containing mainly alkali metals or alkaline earth metals. The tetrahedron of (Si, Al) O ₄ forms a three-dimensional stereoscopic skeleton structure by apical oxygen, Large pores are formed in the water and contain water molecules and exchangeable cations. Water molecules are easily removed by relatively low temperature heating, but since the skeleton of zeolite structure does not change, zeolite after heating can absorb moisture in the air, and the chemical composition is W _y (Si, Al) (O ₂ × nH ₂ O) W is mainly composed of sodium (Na) and calcium (Ca) and contains potassium (K), magnesium (Mg), barium (Ba), lithium (Li), and the like. In addition, the zeolite has a pore size of a certain size, selectively adsorbs through molecules smaller than this, and selectively adsorbs unsaturated hydrocarbons or polar substances strongly by the action of cations in the crystal structure. In addition, the cation can be easily exchanged with other cations to remove harmful substances, to concentrate and recover useful components and to replace some of the cations with anions to have an antimicrobial effect to maintain the quality and freshness of food do.

The diatomaceous earth is a rock or sediment formed by the accumulation of diatoms, which are single-celled organisms, mainly composed of silicon dioxide (SiO 2), most of which is amorphous silica, and some crystalline silica is present therein. Due to the complex structure and the primary and secondary pores of the shell, the density is very low and there are a myriad of gaps in the cells of the diatom, which can filter out the impurity particles and have excellent thermal insulation, fire resistance, chemical resistance and absorbency.

Since the illite is a representative clay mineral, it has a large surface area and is rich in reactivity, and has a layered structure, so that pores are formed between the layers, have plasticity in the state of containing water, and have a property of sintering upon heating. Have

The pozzolanic is a porous material, and there are natural pozzolanics such as cement mixtures, soluble clay, silicate clay, parous rock, and artificial pozzolanics such as fly-ash, which contains a lot of soluble silicic acid and is hydrophobic. Although it is hard to combine with lime and harden in the presence of water, it absorbs and adsorbs volatile organic compounds harmful to human body such as formaldehyde, generates far infrared rays and anions, removes odor, removes mold, removes odor, sterilizes, and supplies oxygen. To have the effect of.

More specifically, by using a mixture of zeolite, diatomaceous earth, elite and pozzolane in a weight ratio of 1: 1: 2: 2 as the natural mineral, the above effects can be further improved. In addition, the natural mineral is crushed to a particle size of 200 to 500 mesh, thereby further improving the above effects, and further improve the miscibility and dispersibility with other components to improve the strength.

Subsequently, with respect to 100 parts by weight of the pulverized natural mineral, 10 to 30 parts by weight of calcium carbonate, 5 to 15 parts by weight of acrylate copolymer, 1 to 5 parts by weight of surfactant and 500 to 1000 parts by weight of water are mixed, A suspension of natural minerals and calcium carbonate having excellent acidity is prepared.

The calcium carbonate has no toxicity to the human body and has antibacterial and bactericidal power against various harmful bacteria and microorganisms, and has high hydrophilicity and low oil absorption as well as functions as an extender and a reinforcing agent having excellent hardness, heat insulation, moisture absorption, and hiding ability. It is excellent in homogeneity and serves to control the flowability of the ceramic particles while being dispersed in water to form a suspension. In addition, by mixing and molding with the natural mineral and pulp to smooth the surface of the pulp molded body, it is possible to prevent the strength of the pulp molded body is lowered by the moisture of the package object.

The calcium carbonate preferably has a small particle size. The smaller the particle size is, the more the fibers are inserted between the fibers of the pulp so that the fibers do not spread between the fibers, so that the fibers can be formed in close contact with each other. As a result, the strength of the pulp molded body can be improved and cracking can be suppressed.

More specifically, the calcium carbonate present in the suspension of natural minerals and calcium carbonate having excellent dispersibility may further improve the above effects by using an average particle diameter of 100 to 700 nm.

The acrylate copolymer is present in the suspension of natural minerals and calcium carbonate because of the three-dimensional cross-linked structure has a network-type bonding structure, significantly improving the dispersibility and sustainability of the natural mineral and calcium carbonate It can be effective. As a result, the natural mineral and calcium carbonate are very evenly distributed, so that the effects of antimicrobial activity and gas adsorption capacity are remarkably improved. Such acrylate-based copolymers are generally used in the art and are not particularly limited in kind. For example, acrylate / acrylamide copolymer, acrylate / acetoacetoxyethyl methacrylate-acrylate copolymer and acryl. It is preferable to use at least one selected from the group consisting of a rate / C 10 -C 30 alkylacrylate crosspolymer.

The surfactant allows the natural mineral and calcium carbonate to be easily distributed in the three-dimensional crosslinked structure of the acrylate copolymer, thereby further improving dispersibility and sustainability of the dispersion. As a result, the natural mineral and calcium carbonate are very evenly distributed, so that the effects of antimicrobial activity and gas adsorption capacity are remarkably improved.

Such a surfactant can further improve the above effects by using a compound represented by the following formula (1).

[Formula 1]

In Formula 1, R ₁ is an alkyl group having 5 to 20 carbon atoms, R ₂ is an alkyl group having 1 to 10 carbon atoms, and X is 1 to 40.

In addition, the surfactant represented by the formula (1) is polyoxyethylene glycol ether, polyoxyethylene polyoxypropylene glycol ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl ether, naphthyl polyoxyethylene ether, polyoxyethylene lanolin By using in combination with one or more selected from the group consisting of alcohol ethers and mixtures thereof, the above effects can be further improved. In particular, by using the surfactant and polyoxyethylene polyoxypropylene glycol ether represented by the formula (1) in a weight ratio of 4: 1, the above effects can be further improved.

Then, with respect to 100 parts by weight of one or more pulp selected from the group consisting of coniferous pulp, hardwood pulp, highland pulp and mixtures thereof, 1000 to 2000 parts by weight of water, 5 to 25 parts by weight of calcium carbonate, 1 to 5% by weight 50 to 70 parts by weight of aqueous calcium hydroxide solution and 0.1 to 2 parts by weight of citric acid are mixed and stirred, followed by carbonization by injecting CO ₂ gas, and further adding 5 to 15 parts by weight of a water-soluble polymer while the carbonation is in progress. A pulp suspension is prepared in which calcium is evenly attached to the pulp surface.

Since the pulp contains a large amount of lignin components, it is possible to increase the binding force of the pulp molded body and to use the wood shreds after a simple treatment process, thereby reducing the manufacturing cost, and the chemical treatment is omitted, thereby causing environmental pollution. Since the absorption is fast and uniform and excellent in water adsorption and gas binding power, there is an effect of maintaining freshness and preservation when the packaging object is food.

In particular, by using coniferous pulp, hardwood pulp, and paper pulp, long and short types of fibers are mixed to form pulp moldings, resulting in high density of pulp moldings, and dispersing and dispersing the natural minerals and calcium carbonates among these fibers. Insertion and fixation increase the strength of the pulp moldings, and natural minerals and calcium carbonate are sandwiched between densely packed fibers, thus preventing the powders from being separated and being incorporated into packages such as foods during the use of pulp moldings. It is effective.

The calcium carbonate has an effect of inducing the growth of calcium carbonate produced by carbonation evenly between pulp by using an average particle diameter of 1 to 100 nm. Thereby, there is an effect that the strength of the pulp molded body is significantly improved.

The citric acid develops and further micronizes the pores of the calcium carbonate produced by carbonation, and has an effect of making the specific surface area large and excellent in reactivity.

The carbonation may be performed by stirring while maintaining a stirring speed of 1000rpm, CO ₂ gas flow rate at 0.7L / min.

The water-soluble polymer plays a role of evenly attaching calcium carbonate to the pulp surface, and the water-soluble polymer is a water-soluble polymer generally known in the art, and the type thereof is not particularly limited. For example, the above effects can be further improved by using a mixture of polymethacrylic acid (PMAA) and water-soluble cellulose in a 2: 1 weight ratio. At this time, the water-soluble cellulose may be preferably used at least one selected from the group consisting of hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC), carboxymethyl cellulose (CMC) and mixtures thereof. .

This makes it possible to prepare a pulp suspension in which calcium carbonate having excellent particle shape and dispersion stability is evenly attached to the pulp surface while removing contaminants that may be present in the pulp. As a result, not only the strength of the pulp molded body is remarkably improved, but as a result, the antibacterial performance and the gas adsorption performance are excellent.

Subsequently, by molding the suspension using the suspension of the natural mineral and calcium carbonate and the pulp suspension in a ratio of 1: 5 to 10 by weight, a pulp molded article having excellent antibacterial performance and gas adsorption performance and excellent strength was formed. To manufacture.

The mold molding is performed by injecting a suspension of the natural minerals and calcium carbonate and a mixed solution of the pulp suspension in a ratio of 1: 5 to 10 by weight to a lower mold heated to 100 to 400 ° C., and then placing the 100 on the lower mold. It can be carried out by molding the upper mold heated to to 400 ℃ by compression and molding. More preferably, in consideration of the uniform distribution of the components in the mixed solution and thus the strength of the final pulp molded body, the lower mold and the upper mold are preferably heated to 280 to 380 ° C, respectively.

At this time, between the lower mold and the upper mold heated to 100 to 400 ℃, respectively, the mixed solution is continuously heated, and the compression / decompression and vacuum / vacuum release is repeated repeatedly. As a result, the pulp molded body can be produced by easily and quickly removing water.

A schematic image of a molding tank for manufacturing pulp molded body according to one embodiment of the present invention is shown in FIG. 1.

More specifically, when the mixed solution is injected into the molding molding tank and filled, the lower mold heated to 100 to 400 ° C. adsorbs the mixed solution to the lower mold surface by vacuum adsorption, and the water in the mixed solution is transferred to the lower mold. It is first removed from the surface of. In this state, the upper mold heated to 100 to 400 DEG C is lowered to form a lower mold, compressed and molded into a product shape, thereby producing a primary molded body containing a small amount of water.

Subsequently, when the vacuum of the lower mold is released and the upper mold is vacuumed, the upper mold vacuum-adsorbs the primary molded body to attach to the surface of the upper mold and then raises the upper mold. In this process, a small amount of water contained in the primary molded body is secondarily removed from the upper mold surface by vacuum adsorption. Subsequently, the upper mold is lowered again to form a lower mold, compressed and molded into a product shape, whereby a secondary molded body containing a trace amount of water is produced.

On the contrary, when the vacuum of the upper mold is released and the vacuum is applied to the lower mold, the lower mold raises the upper mold after vacuum adsorbing the secondary molded body to the surface of the lower mold. In this process, the trace amount of water contained in the secondary molded body is thirdly removed from the lower mold surface by vacuum adsorption. Subsequently, the upper die is lowered again to be joined with the lower die, compressed and molded into a product shape, whereby a tertiary molded body containing a very small amount of water is produced.

In the above, the lower mold is fixed and the upper mold is lowered and raised, but the upper mold is fixed and the lower mold is raised and lowered as necessary, or the lower mold and the upper mold is configured to be raised and lowered alternately You may.

In addition, after the production of the primary to the third molded article, they can be directly dried by heating in a drying apparatus. More specifically, after manufacturing the first to third molded articles, each is transferred by a conveyor belt while using a heat drying apparatus of various methods such as a heater, an infrared lamp, hot air, etc. It may be dried for 3 to 10 minutes at a temperature of from 200 ℃. As a result, the manufacturing time can be shortened, and the processes can be performed in a continuous process.

Thus, the pulp molded body according to one embodiment of the present invention can be produced.

That is, since the lower mold and the upper mold are alternately vacuum-adsorbed, the water contained in the pulp molded body is alternately removed in the downward and upward directions, so that the components constituting the pulp molded body can be uniformly distributed without being biased up and down by vacuum adsorption. It has an effect.

In addition, the heating of the pulp molded body is also alternately up and down according to the vacuum adsorption of the lower mold and the upper mold, so that heat is uniformly provided up and down, so that drying is uniform, thereby improving the strength and impact resistance of the pulp molded body. It is. In addition, the phenomenon that the pulp molded body is discolored by high temperature heating can be prevented.

In addition, since either side of the lower mold and the upper mold is spaced apart by the vacuum suction of water, water can be smoothly removed from the pulp molded body, and since the lower mold and the upper mold are not vacuum suction at the same time by vacuum adsorption The fall of the strength of a molded object is prevented.

In other words, the water is discharged alternately to the upper and lower parts of the molded body, and the upper and lower parts of the molded body are alternately heated to dry uniformly. The occurrence is reduced.

Thus, the method for producing a pulp molded body according to the embodiment of the present invention has an effect of providing a pulp molded body having excellent antibacterial performance and gas adsorption capacity and excellent strength.

In addition, another embodiment of the present invention provides a pulp molded body produced by the method for producing a pulp molded body according to the embodiment of the present invention.

The pulp molded body according to one embodiment of the present invention exhibits strong antibacterial activity against microorganisms such as bacteria, molds and yeasts that cause decay and decay of contents, such as fruit and vegetables, to maintain the freshness of contents such as fruits and vegetables for a long time. It is effective to increase.

In addition, it has excellent gas adsorption ability to adsorb and remove fruit-causing substances such as ethylene gas, amine, ammonia, acetic acid, etc., and solves the problem that freshness is rapidly deteriorated by ethylene gas generated during the cellular respiration process of fresh food. It is very suitable as a packaging material for fresh food and / or precision appliances.

Furthermore, by solving the problem that the damage of the product can be caused by the harmful gas such as carbon dioxide or ammonia generated from the inside of the packaging box, there is a very suitable effect as a packaging material for precision machinery such as watches and cameras.

In addition, the pulp molded body according to one embodiment of the present invention has an excellent tensile strength.

Hereinafter, the configuration and operation effects of the present invention through the examples will be described in more detail. However, it is apparent to those skilled in the art that the present invention is not limited only to these examples.

Example 1

For natural minerals of 13 g of zeolite, 34 g of diatomaceous earth, 22 g of illite, and 31 g of pozzolane, it was ground to a particle size of 250 mesh.

) 2g 및 물 700g을 혼합하여, 분산성이 우수한 천연광물 및 탄산칼슘의 현탁액을 제조하였다.100 g of the ground natural mineral, 25 g of calcium carbonate having an average particle diameter of about 578 nm, 7 g of an acrylate copolymer (acrylate / acetoacetoxyethyl meth-acrylate copolymer), a surfactant (

2g) and 700g of water were mixed to prepare a suspension of natural mineral and calcium carbonate having excellent dispersibility.

To a pulp of 37 g of coniferous pulp, 37 g of hardwood pulp, and 26 g of highland pulp, 1800 g of water, 5 g of calcium carbonate having an average particle diameter of about 74 nm, 60 g of calcium hydroxide aqueous solution, and 0.5 g of citric acid were mixed at a stirring speed of 1000 rpm. While stirring, the gas flow rate was maintained at 0.7 L / min and carbonized by injecting CO ₂ gas, and 6 g of polymethacrylic acid (PMAA) and 3 g of hydroxypropylmethylcellulose (HPMC) were further added during the carbonation. A pulp suspension in which calcium carbonate was evenly attached to the pulp surface was prepared.

300 g of the prepared suspension of natural minerals and calcium carbonate and 1800 g of the pulp suspension were mixed into a molding tank as shown in FIG.

The molding tank is provided with a lower mold and an upper mold, which are inscribed to form a box-shaped molded body in combination with each other, and are equipped to move up and down and apply a vacuum to an object placed on the mold surface. After heating the lower mold and the upper mold to 350 ℃ and moving the lower mold below the water surface of the mixed solution filled in the molding tank and raised above the water surface so that the pulp composition is contained in the lower mold mold surface, and stop and apply vacuum Water was first removed.

Subsequently, the upper mold was lowered to be molded and compressed with the lower mold, and the first mold was manufactured by dehydration and primary drying while molding into a box shape.

Subsequently, the vacuum of the lower mold was released, the vacuum was applied to the upper mold, and the upper mold was raised so that the water in the primary molded body was secondarily removed while the primary molded body was raised in a vacuum adsorbed state on the mold surface of the upper mold.

The upper mold is lowered again to form and compact with the lower mold to prepare a secondary dried secondary molded article.Then, the vacuum of the upper mold is released, the vacuum is applied to the lower mold, and the upper mold is raised to raise the secondary molded article. Vacuum adsorption was carried out on the mold surface of the mold to cause the water in the secondary molded body to be removed third.

Subsequently, the upper mold was lowered again to be combined with the lower mold and compressed to prepare a tertiary dried tertiary molded body. After the upper mold was raised, the pulp molded body was removed by releasing the vacuum of the lower mold and taking out the tertiary molded body. Prepared.

Test Example 1: Antimicrobial Performance Test

The pulp molded body manufactured in the above example was commissioned by the Korea Institute of Construction and Environmental Testing and Research to test the antimicrobial performance and the results are shown in Table 1, FIG. 2 and FIG. 3. Test strains were Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 6538), Klebsiella pneumoniae (ATCC 4352), Salmonella Enterica (KCTC 1925), and KS K 0693: 2006 test methods. Tested according to.

Test Items Test result at (37.0 ± 0.2) ℃ Initial bacterial count
(CFU / mL) After 18 hours
(CFU / mL) Bacterial reduction rate
(%) Escherichia coli Example 3.1 × 10 ⁵ <50 99.9 Control 8.0 × 10 ⁷ - Staphylococcus aureus Example 2.3 × 10 ⁵ <50 99.9 Control 2.9 × 10 ⁸ - Pneumococcal Example 3.6 × 10 ⁵ <50 99.9 Control 1.7 × 10 ⁸ - Salmonella Example 2.4 × 10 ⁵ <50 99.9 Control 1.1 × 10 ⁸ -

As can be seen in Table 1, after 18 hours, bacteria were grown in the control piece (stomacher film), but in the pulp molded body according to the embodiment, the bacteria were killed and the bacterial reduction rate was confirmed to be 99.9%. In addition, this could be confirmed through visual observation results of FIGS. 2 (pneumonia) and 3 (salmonella).

Thereby, it was confirmed that the pulp molded body of the example was very excellent in antibacterial activity.

Test Example 2: Analysis of Ethylene Content Change in Fruit Storage

The pulp molded product (box) prepared in the above example was sealed with apples and stored for 14 days, and then changed to ethylene content at 1 and 14 days after storage. At this time, the ethylene content analysis was carried out using a gas syringe (GC-14B, Shimadzu, Japan) equipped with a thermal conductivity detector (TCD) after collecting the air in the box with a syringe syringe, helium (helium) as a carrier gas , 20 cc / min) and Porapak Q (80-100 mesh, 3 mmΦ × 2 m, stainless steel tube) were used for the packing. As a control, apples were stored in a normal cardboard box and stored for 14 days, and then compared with the above examples.

Mg / l 1 day 14 days Example 3.52 ± 0.37 6.12 ± 1.41 Control 2.15 ± 0.56 9.85 ± 0.89

As can be seen in Table 2, the pulp molded body (box) according to an embodiment of the present invention is adsorbed ethylene gas generated in the apple after 14 days of storage and it can be seen that the ethylene gas content in the box is lower than that of a normal cardboard box there was. As a result, the freshness of apples can be suppressed during storage to maintain freshness for a long time and extend the shelf life.

Test Example 3 Experiment of Adsorption of Hazardous Gases

The gas adsorption characteristics of the pulp molded bodies prepared in the above examples were evaluated. Gas adsorption characteristics were cut into 5 cm x 5 cm x 0.37 mm (width x length x thickness) of the pulp molded body, and then placed in a desiccator and exposed to ammonia gas for 7 days. Since the ammonia adsorption amount was measured by the following method and described in Table 3. At this time, the ammonia adsorption amount (µl / kg) was performed according to KS M 1998-4. As a control, gas adsorption characteristics were compared using a normal cardboard box.

Μl / kg Ammonia adsorption amount Example 852 Control 49

As can be seen in Table 3, the pulp molded body according to the embodiment of the present invention was confirmed that the adsorption effect of harmful gases such as ammonia is very excellent. As a result, it is considered to be very suitable as a wrapping paper for fresh food and / or precision home appliances.

Test Example 4: Measurement of Tensile Strength

The tensile strength of the pulp molded bodies prepared in the above examples was evaluated. The tensile strength evaluation was performed according to KS M 7014. The measured tensile strengths are shown in Table 4 below. In addition, as a control, the tensile strength was compared using a normal cardboard box.

(kN / m) The tensile strength Example 54 Control 21

As can be seen in Table 4, the pulp molded body according to an embodiment of the present invention can provide a pulp molded body having a very improved strength and less damage.

As described above, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, it should be understood that the embodiments described above are all illustrative and not restrictive. The scope of the present invention should be construed as being included in the scope of the present invention all changes or modifications derived from the meaning and scope of the appended claims rather than the detailed description and equivalent concepts thereof.

Claims (4)

Pulverizing the particle size to 200 to 500 mesh for at least one natural mineral selected from the group consisting of zeolite, diatomaceous earth, elite, pozolan and mixtures thereof;
10 to 30 parts by weight of calcium carbonate, 5 to 15 parts by weight of acrylate copolymer, 1 to 5 parts by weight of surfactant, and 500 to 1000 parts by weight of water are mixed with respect to 100 parts by weight of the natural minerals pulverized, thereby providing excellent dispersibility. Preparing a suspension of natural mineral and calcium carbonate;
1000 to 2000 parts by weight of water, 5 to 25 parts by weight of calcium carbonate, and 1 to 5% by weight with respect to 100 parts by weight of one or more pulp selected from the group consisting of coniferous pulp, hardwood pulp, highland pulp and mixtures thereof. 50 to 70 parts by weight of an aqueous calcium hydroxide solution and 0.1 to 2 parts by weight of citric acid are mixed and stirred, followed by carbonization by injecting CO ₂ gas, and further adding 5 to 15 parts by weight of a water-soluble polymer in the course of the carbonation. Preparing a pulp suspension evenly attached to the pulp surface; And
Pulp molded body comprising the step of forming a pulp molded body by molding, using a suspension of the natural minerals and calcium carbonate, and a mixed solution of the pulp suspension in a ratio of 1: 5 to 10 by weight Manufacturing method.
The method of claim 1,
In the step of preparing a suspension of the natural mineral and calcium carbonate,
The calcium carbonate has an average particle diameter of 100 to 700 nm,
The acrylate copolymer is at least one acrylate selected from the group consisting of an acrylate / acrylamide copolymer, an acrylate / acetoacetoxyethyl methacrylate-acrylate copolymer and an acrylate / C10-C30 alkylacrylate crosslinked polymer. It is a system copolymer,
The surfactant is a method for producing a pulp molding, characterized in that the compound represented by the following formula (1).
[Formula 1]

In Formula 1, R ₁ is an alkyl group having 5 to 20 carbon atoms, R ₂ is an alkyl group having 1 to 10 carbon atoms, and X is 1 to 40.
The method of claim 1,
In the step of preparing the pulp suspension,
The calcium carbonate has an average particle diameter of 1 to 100 nm,
The water-soluble polymer is a method of producing a pulp molded body, characterized in that the polymethacrylic acid (PMAA) and water-soluble cellulose mixed in a 2: 1 weight ratio.
A pulp molded article produced by the method for producing a pulp molded article according to any one of claims 1 to 3.

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