Method for manufacturing paper-making filler using mixed solution of organic fiber and inorganic compound and use thereof

Abstract

The present invention relates to a method for manufacturing a paper-making filler using a mixed solution of an organic fiber and an inorganic compound, and a use thereof. The paper including the paper-making filler manufactured by the manufacturing method according to the present invention has greatly improved bulk compared to paper using an existing ground calcium carbonate filler, thus exhibiting excellent breaking length and superior smoothness. With such characteristics, high-quality paper can be produced even when using a larger amount of filler than ground calcium carbonate, thereby enhancing economic efficiency, reducing the amount of organic fiber used, and achieving energy savings in drying.

Description

Method for producing a paper-making filler using a mixed solution of organic fibers and inorganic compounds and its use

[0001] The present invention relates to a method for producing a paper-making filler using a mixed solution of organic fibers and inorganic compounds and to a use thereof.

[0002] Raw materials used in the manufacture of printing paper include wood pulp, fillers, and other additives. Wood pulp is the primary raw material, with the highest content of fillers. Fillers are used to improve paper quality, including opacity, brightness, and printability. However, because fillers are cheaper than wood pulp, replacing them with pulp can also lead to cost savings.

[0003] The paper industry has recently been facing rising prices not only for pulp raw materials but also for oil. Therefore, the development of efficient utilization technologies for fillers, which are not only cheaper than pulp but also offer advantages in terms of drying load, is a critical task. However, these fillers have limitations due to their ability to inhibit hydrogen bonding between fibers and reduce the tensile strength and stiffness of paper. To overcome these issues, various solutions have been explored. To increase filler content while preventing paper strength loss, numerous technologies have been developed and implemented, including fiber-filler composites, preflocculation, lumen loading, and hybrid calcium carbonate.

[0004] For example, prefloc technology involves mixing calcium carbonate and an ionic polymer to form clumps of calcium carbonate particles, which are then subjected to a strong vortex to form a stable prefloc of a consistent size. These preflocs are used as raw materials for papermaking. Adding preflocs to papermaking materials yields paper with higher tensile strength than paper made with conventional calcium carbonate. However, their use is limited because they do not increase bulk.

[0005] As a conventional technology for manufacturing paper fillers, Korean Patent Publication No. 2009-0040682 discloses a method for manufacturing paper using amphoteric polyacrylamide for pre-agglomeration of filler, Korean Patent Publication No. 2005-0023824 discloses a method for manufacturing paper using cationic starch, and Korean Patent Publication No. 2015-1510313 discloses a method for manufacturing hybrid calcium carbonate by pre-agglomerating calcium carbonate and a calcium compound with an ionic polymer and then blowing carbon dioxide to cause the calcium carbonate and the newly formed calcium carbonate to coagulate. However, a method for manufacturing a paper filler using the mixed solution of organic fiber and inorganic compound of the present invention and its use have not yet been disclosed.

[0006] The present invention was derived from the above-mentioned needs, and the present invention provides a method for producing a paper-making filler using a mixed solution of organic fibers and inorganic compounds and a use thereof, and completed the present invention by confirming that paper produced using a filler produced by the filler production method of the present invention has superior bulk and heat-breakability compared to paper produced by a conventional production method.

[0007] In order to achieve the above object, the present invention provides a method for producing a paper-making filler, comprising the steps of (1) preparing a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 μm and a fiber fibril having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100 and a solid content of 1 to 60 wt%, (2) adding an ionic polymer to the mixed aqueous solution and stirring to form a pre-agglomerate, and (3) adding 10 to 1000 parts by weight of a calcium compound to 100 parts by weight of the inorganic compound contained in the mixed aqueous solution in which the pre-agglomerate is formed, and then injecting carbon dioxide at 10 to 80 degrees Celsius until the pH is maintained at 7.0±1.0, thereby producing a paper-making filler.

[0008] According to an embodiment of the present invention, the step (1) may include: (1-1) a step of mixing organic fibers and inorganic compounds in a weight ratio of 1:5 to 100, and then adding water to prepare a mixed solution having a solid content of 1 to 60 wt%, and (1-2) a step of grinding the mixed solution to prepare a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 μm and fiber fibrils having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100, and having a solid content of 1 to 60 wt%.

[0009] In addition, the inorganic compound may be at least one selected from calcium carbonate (CaCO3), calcium oxide (CaO), calcium hydroxide (Ca(OH)2), magnesium carbonate (MgCO3), gypsum, kaolin, calcined clay, talc, perlite, diatomaceous earth, zinc carbonate, lithium carbonate, magnesium hydroxide, and aluminum trihydrate.

[0010] Additionally, the calcium carbonate may be at least one selected from ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC).

[0011] Additionally, the fiber fibrils may include at least one selected from cellulose and chitin.

[0012] Additionally, the ionic polymer may be at least one selected from an anionic polymer and a cationic polymer.

[0013] In addition, the anionic polymer may be at least one selected from polysaccharides, proteins, polyvinyl alcohol, polyvinyl acetate, cellulose derivatives, epoxy acrylates, polyesters, polyurethanes, polyester acrylates, polyether acrylates, polyolefin dispersions, polyamides, vinyl copolymers, and polyacrylates.

[0014] Additionally, the cationic polymer may be at least one selected from polyamidoamine-epihalohydrin polymer, polyalkyldiallylamine-epihalohydrin polymer, polyethyleneimine, polyacrylamide, polyamine, polyvinylamine, and cationic starch.

[0015] In addition, in the above step (2), the amount of ionic polymer added may be 0.01 to 10 parts by weight of one or more ionic polymers per 100 parts by weight of the mixed aqueous solution.

[0016] Additionally, in the above step (3), the calcium compound may be at least one selected from calcium oxide, calcium hydroxide, calcium sulfate, and calcium phosphate.

[0017]

[0018] In addition, the present invention provides a papermaking filler having a shape in which a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a metal carbonate is arranged on the fiber fibrils, and comprising 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate (this filler is hereinafter referred to as HFCC (hybrid flexible calcium carbonate)).

[0019]

[0020] In addition, the present invention provides a method for manufacturing paper, comprising the steps of (1) mixing 1 to 60 wt% of the above-described papermaking filler (HFCC) and 40 to 99 wt% of refined natural pulp or recycled pulp, and (2) introducing the mixture of step (1) into a paper machine to manufacture paper.

[0021]

[0022] In addition, the present invention provides a method for producing ultra-high-filled paper in which inorganic matter accounts for 50 wt% or more of the total weight, the method comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler (HFCC) and 1 to 40 wt% of refined natural pulp or recycled pulp; and adding 1 to 30% of an ionic polymer for strength enhancement, and (2) feeding the mixture of step (1) into a paper machine to produce paper.

[0023]

[0024] In addition, the present invention provides a method for producing a composite, comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler (HFCC) and 1 to 50 wt% of refined natural pulp or recycled pulp; (2) feeding the mixture of step (1) into a paper machine to produce a sheet in the form of paper; and (3) after step (2), impregnating, spraying, or curtain coating 50 to 5,000 wt% of a synthetic polymer or biodegradable polymer with respect to 100 wt% of the produced sheet to produce a composite.

[0025]

[0026] In addition, the present invention provides a method for manufacturing stone paper, comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler and 1 to 50 wt% of refined natural pulp or recycled pulp; (2) feeding the mixture of step (1) into a paper machine to manufacture a sheet in the form of paper; and (3) after step (2), coating or impregnating 1 to 50 wt% of a synthetic polymer or biodegradable polymer with respect to 100 wt% of the manufactured sheet to manufacture stone paper.

[0027]

[0028] In addition, the present invention provides paper characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0029] At this time, the paper may contain 1 to 60 wt% of the filler (HFCC).

[0030]

[0031] In addition, the present invention provides an ultra-high-filled paper characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0032] At this time, the ultra-high-filled paper may contain the filler (HFCC) in an amount of 50 wt% or more of the total ultra-high-filled paper weight.

[0033]

[0034] In addition, the present invention provides a composite characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0035]

[0036] In addition, the present invention provides a stone paper characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0037] The present invention relates to a method for producing a papermaking filler using a mixed solution of organic fibers and inorganic compounds, and to a use thereof. Paper containing a papermaking filler produced by the method according to the present invention has a significantly improved paper bulk compared to paper using conventional heavy calcium carbonate fillers, has the effect of excellent heat breaking strength, and has excellent smoothness characteristics. By utilizing these characteristics, it is possible to produce high-quality paper using a larger amount of filler than heavy calcium carbonate, thereby achieving excellent economic efficiency, reducing the amount of organic fiber used, and reducing drying energy.

[0038] Figure 1 is a process flow chart briefly showing the process of manufacturing paper using a papermaking filler manufactured according to the present invention.

[0039] Figure 2 compares the bulk (A), heat breakage (B), and internal bonding strength (C) of paper manufactured in Examples 4 to 9 and Comparative Examples 1 to 4 of the present invention.

[0040] FIG. 3 is an electron microscope photograph of the carbon dioxide reaction time in step 3 of Example 1 of the present invention, where FIG. 3a is an electron microscope photograph of the initial state of the carbon dioxide reaction, FIG. 3b is an electron microscope photograph of the intermediate state of the carbon dioxide reaction, and FIG. 3c is an electron microscope photograph of the final form of the carbon dioxide reaction in FIG. 3a.

[0041] The present invention relates to a method for producing a paper-making filler (HFCC), comprising the steps of: (1) preparing a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 μm and fiber fibrils having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100 and a solid content of 1 to 60 wt%; (2) adding an ionic polymer to the mixed aqueous solution and stirring to form a pre-agglomerate; and (3) preparing a paper-making filler by adding 10 to 1000 parts by weight of a calcium compound to 100 parts by weight of the inorganic compound contained in the mixed aqueous solution in which the pre-agglomerate is formed, and then injecting carbon dioxide at 10 to 80 degrees Celsius until the pH is maintained at 7.0±1.0.

[0042] At this time, the step (1) may be performed by 1) preparing a separate mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 μm and a fiber fibril having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100, 2) preparing by mixing an inorganic compound having an average size of 0.1 to 10 μm and a fiber fibril having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100, or 3) mixing and grinding an organic fiber and an inorganic compound to prepare a mixed aqueous solution having the same size and weight ratio.

[0043] According to an embodiment of the present invention, the step (1) may include: (1-1) a step of mixing organic fibers and inorganic compounds, and then adding water to prepare a mixed solution; and (1-2) a step of grinding the mixed solution to prepare a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 μm and fiber fibrils having an average width of 5 nm to 10 μm in a weight ratio of 1:5 to 100 and having a solid content of 1 to 60 wt%.

[0044] At this time, in the step (1-1), the organic fiber and the inorganic compound can be mixed in a weight ratio of 1:5 to 100, and the mixed solution can have a solid content of 1 to 60 wt%.

[0045] In the above step (1-2), the step of grinding the mixed solution of organic fibers and inorganic compounds not only reduces the size of the inorganic compounds to an appropriate level, but also allows the organic fibers to be fibrillated with less energy by friction with the inorganic compound in a strong alkaline state resulting from hydration of the inorganic compounds, thereby significantly reducing energy consumption in the production of organic fiber fibrils compared to a method of separately producing and using microfibrils or nanofibrils. The grinding is preferably performed using a grinder or a ball mill, but is not limited thereto.

[0046] In the above steps (2) and (3), a pre-aggregate is manufactured using a mixed inorganic compound and organic fiber fibrils, and calcium oxide is added thereto and carbon dioxide is blown therein, thereby reacting in water, thereby attaching a metal carbonate to the surface of the pre-aggregate, so that a solid and elongated metal carbonate can be manufactured.

[0047] Preflocculation in the present invention means changing inorganic compound particles and organic fiber fibrils into aggregates by treating them with coagulants and flocculants.

[0048] It is preferable that the stirring in the above step (2) be performed at 500 to 5,000 rpm. If stirring is performed at less than 500 rpm, the size of the formed aggregate particles is very large, so if this is used to manufacture paper, the problem of poor paper properties occurs. If stirring is performed at more than 5,000 rpm, the size of the particles becomes too small, so the problem of ineffectiveness occurs.

[0049] The particle size of the pre-agglomerate formed in the above step (2) may be 1 to 100 μm.

[0050] If the particle size of the pre-agglomerate formed in the above step (2) is less than 1㎛, there is a problem that the size of the pre-agglomerate is very small and there is no effect of improving the properties of the paper manufactured using it, and if it exceeds 100㎛, there is a problem that it is difficult to uniformly distribute the filler when manufacturing paper using it.

[0051] The above inorganic compound may include at least one selected from calcium carbonate (CaCO3), calcium oxide (CaO), calcium hydroxide (Ca(OH)2), magnesium carbonate (MgCO3), gypsum, kaolin, calcined clay, talc, perlite, diatomaceous earth, zinc carbonate, lithium carbonate, magnesium hydroxide, and aluminum trihydrate, and preferably may include a metal carbonate including at least one selected from calcium carbonate, magnesium carbonate, aluminum carbonate, lithium carbonate, and zinc carbonate, and more preferably may be calcium carbonate, but is not limited thereto.

[0052] The above calcium carbonate is preferably, but not limited to, at least one selected from ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC), and the above fiber fibrils are preferably, but not limited to, one selected from cellulose and chitin.

[0053] The above ionic polymer is preferably at least one ionic polymer selected from among anionic polymers and cationic polymers, but is not limited thereto.

[0054] The anionic polymer is preferably at least one selected from among polysaccharides, proteins, polyvinyl alcohol, polyvinyl acetate, cellulose derivatives, epoxy acrylates, polyesters, polyurethanes, polyester acrylates, polyether acrylates, polyolefin dispersions, polyamides, vinyl copolymers, and polyacrylates, but is not limited thereto. The cationic polymer is preferably at least one selected from among polyamidoamine-epihalohydrin polymers, polyalkyldiallylamine-epihalohydrin polymers, polyethyleneimines, polyacrylamide, polyamines, polyvinylamine, and cationic starches, but is not limited thereto.

[0055] In the above step (2), the amount of ionic polymer added is preferably 0.01 to 10 parts by weight of ionic polymer per 100 parts by weight of the mixed aqueous solution, more preferably 0.1 to 0.3 parts by weight of ionic polymer, but is not limited thereto.

[0056] In the above step (3), the calcium compound is preferably one or more calcium compounds selected from calcium oxide, calcium hydroxide, calcium sulfate and calcium phosphate, more preferably calcium oxide or calcium hydroxide, but is not limited thereto.

[0057] When calcium hydroxide is used as the above calcium compound, calcium hydroxide may be calcium hydroxide produced by reacting sodium hydroxide and calcium chloride. That is, since calcium hydroxide can be formed by reacting sodium hydroxide and calcium chloride, calcium carbonate can be formed by reacting with carbon dioxide even without directly adding calcium hydroxide.

[0058] In the above step (3), calcium contained in the calcium compound component in the diluted solution in which the pre-agglomerate is formed is dissolved in the form of a salt such as calcium hydroxide, and calcium carbonate can be synthesized through a carbonation reaction by blowing carbon dioxide into it. At this time, it is preferable to react the carbon dioxide until the pH of the diluted solution generally reaches 7.0, and it is necessary to carry out the reaction until no more injected carbon dioxide reacts. In addition, in the above step (3), the temperature at which the diluted solution is reacted by injecting carbon dioxide is preferably 10 to 80°C.

[0059]

[0060] In addition, the present invention provides a paper-making filler having a shape in which a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a metal carbonate is arranged on the fiber fibrils, and comprising 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0061] Since the filler has a shape in which the metal carbonate is arranged on the fiber fibrils, the bulk of the paper is greatly improved when the paper is formed by including the filler, thereby providing excellent heat breaking strength and superior smoothness, which is further advantageous. In addition, since the filler satisfies the content ranges of the fiber fibrils and the metal carbonate, the bulk of the paper is greatly improved when the paper is formed by including the filler, thereby providing excellent heat breaking strength and superior smoothness, which is further advantageous.

[0062]

[0063] In addition, the present invention provides a method for manufacturing paper, comprising the steps of (1) mixing 1 to 60 wt% of the above-described papermaking filler (HFCC) and 40 to 99 wt% of refined natural pulp or recycled pulp, and (2) introducing the mixture of step (1) into a paper machine to manufacture paper.

[0064]

[0065] In addition, the present invention provides a method for manufacturing ultra-high-filled paper, comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler; and 1 to 50 wt% of refined natural pulp or recycled pulp; and adding 1 to 30% of an ionic polymer for strength enhancement, and (2) feeding the mixture of step (1) into a paper machine to manufacture ultra-high-filled paper in which inorganic matter accounts for 50 wt% or more of the total weight.

[0066]

[0067] In addition, the present invention provides a method for producing a composite, comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler and 1 to 50 wt% of refined natural pulp or recycled pulp; (2) feeding the mixture of step (1) into a paper machine to produce a sheet in the form of paper; and (3) after step (2), impregnating, spraying, and / or curtain coating 50 to 5,000 wt% of a synthetic polymer or biodegradable polymer with respect to 100 wt% of the produced sheet to produce a composite.

[0068] The composite is a material that exhibits new properties different from those of the previous material by combining two or more materials with different properties. However, the composition remains separate and unchanged, which is the difference from synthetic materials. The composite can replace metal equipment or metal sheets in airplanes or automobiles, and its applications are endless, such as cell phone cases, tennis rackets, golf clubs, industrial pipes, or tanks, and its applications are continuously being developed. In the present invention, by adding a synthetic polymer or biodegradable polymer to the metal carbonate, it has the characteristic of enhancing high strength and dimensional stability, making it suitable for various applications.

[0069]

[0070] In addition, the present invention provides a method for manufacturing stone paper, comprising the steps of (1) mixing 50 to 99 wt% of the above-described papermaking filler and 1 to 50 wt% of refined natural pulp or recycled pulp; (2) feeding the mixture of step (1) into a paper machine to manufacture a sheet in the form of paper; and (3) after step (2), coating or impregnating 1 to 50 wt% of a synthetic polymer or biodegradable polymer with respect to 100 wt% of the manufactured sheet to manufacture stone paper.

[0071] Although the above stone paper is called "paper," it can actually replace paper or plastic. It is sturdy and waterproof, yet, like biodegradable plastic, decomposes quickly after use. It can be processed into various shapes, is foldable, and offers superior printability compared to regular paper.

[0072] The stone papers currently manufactured have a density of 1.0 or higher, which is a disadvantage in that they are heavy when used to make books or printed materials. However, the stone paper manufactured using metal carbonate in the present invention has a density of 1.0 or lower, which is comparable to that of general paper, and has high hydrophobicity, advanced printability, and biodegradability, so it is an inexpensive material that can replace paper made of non-biodegradable plastic or wood.

[0073]

[0074] In addition, the present invention provides paper formed by including a filler having a shape in which a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region and a metal carbonate is arranged on the fiber fibrils, wherein the filler includes 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0075] At this time, the paper may contain 1 to 60 wt% of the filler (HFCC).

[0076] In addition, the present invention provides an ultra-high-filled paper formed by including a filler having a shape in which a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region and a metal carbonate is arranged on the fiber fibrils, and the filler includes 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0077] At this time, the ultra-high-charged paper contains the filler (HFCC) in an amount of 50 wt% or more of the total weight of the ultra-high-charged paper.

[0078] In addition, the present invention provides a composite characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0079] In addition, the present invention provides a stone paper characterized in that a plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in a central region, and a filler having a shape in which a metal carbonate is arranged on the fiber fibrils is formed, and the filler contains 1 to 20% by volume of the fiber fibrils and 80 to 99% by volume of the metal carbonate.

[0080] The above paper and super-filled paper can be further advantageous in terms of having excellent heat resistance and smoothness by using the above filler (HFCC), which greatly improves bulk.

[0081] In addition, the filler may be more advantageous in terms of manufacturing biocomposites and stone paper as it satisfies the weight range of the fiber fibrils and metal carbonate.

[0082] Hereinafter, the present invention will be described in more detail using examples. These examples are intended solely to illustrate the present invention more specifically, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.

[0083]

[0084] Example 1. Preparation of paper filler 1

[0085] Step 1-1: A mixed solution was prepared by adding 2 g of organic fiber and 40 g of calcium oxide (CaO. Taekyung Industry. Diameter: approximately 10 μm) to 200 ml of water.

[0086] The above organic fiber was used after beating hardwood bleached chemical pulp with a standard water content of 200 ml CSF. The average width of the pulp was confirmed to be approximately 15.5 μm.

[0087] Step 1-2: The mixed solution prepared in Step 1-1 was placed in a ball mill and processed for 1 hour. After the ball milling process, the sizes of calcium oxide and organic fiber fibrils were measured using an electron microscope. As a result, the average diameter of calcium oxide was 3.1 μm, and the average width of the organic fibers was confirmed to be approximately 678 nm.

[0088] Step 2: To 100 parts by weight of the total solid content of the mixed aqueous solution of ball-milled calcium oxide and organic fiber fibrils, 0.1 parts by weight of a cationic polymer, polyacrylamide (PAM, Ciba Chemical, Korea), was added to impart weak cationicity. Then, while forming a vortex, 0.1 parts by weight of an anionic polymer, micropolymer (Eka Chemical, Korea), was added to 100 parts by weight of the total solid content to maintain the overall zeta potential, i.e., neutrality of charge. Here, the exact amount of the ionic polymer to be added was based on the zeta potential. Thereafter, the diluted solution was stirred at a rotation speed of 2,000 rpm for 10 minutes to form a preaggregate.

[0089] Step 3: After Step 2, 5 g of calcium oxide was additionally added to the mixed aqueous solution, and carbon dioxide was continuously injected into the diluted solution while stirring at 2000 rpm at 30 degrees Celsius to allow the reaction to proceed until the pH reached 7.0, thereby producing a paper-making filler. Here, the reaction endpoint was set as the point where the carbon dioxide injection rate and the discharge rate became equal.

[0090] At this time, a total of 45 g of calcium oxide reacted to form 80 g of precipitated calcium carbonate, forming a filler attached to 2 g of cellulose fibrils (cellulose fibrils: precipitated calcium carbonate = 1:40).

[0091]

[0092] Example 2. Preparation of paper filler 2

[0093] Step 1-1: A mixed solution was prepared by adding 2 g of organic fiber and 40 g of heavy calcium carbonate (GCC, Omia Korea, diameter 5 μm or more) to 200 ml of water.

[0094] The above organic fiber was used after beating hardwood bleached chemical pulp with a standard water content of 200 ml CSF. The average width of the pulp was confirmed to be approximately 15.5 μm.

[0095] Step 1-2: The mixed solution prepared in Step 1-1 was placed in a ball mill and processed for 1 hour. After the ball milling process, the size of the heavy calcium carbonate and the width of the organic fiber fibrils were measured using an electron microscope. As a result, the average diameter of the calcium carbonate was 3.2 μm, and the average width of the organic fibers was confirmed to be approximately 825 nm.

[0096] Step 2: For 100 parts by weight of the total solids in the mixed aqueous solution of ball-milled calcium carbonate and organic fiber fibrils, 0.1 parts by weight of a cationic polymer, polyacrylamide (PAM, Ciba Chemical, Korea), was added to impart weak cationicity, and then, while forming a vortex, 0.1 parts by weight of an anionic polymer, micropolymer (Eka Chemical, Korea), was added to 100 parts by weight of the total solids to maintain the overall zeta potential, i.e., neutrality of charge. Here, the exact amount of the ionic polymer added was based on the zeta potential.

[0097] Afterwards, the diluted solution was stirred at a rotation speed of 2,000 rpm for 10 minutes to form a pre-agglomerated calcium carbonate-cellulose fibril.

[0098] Step 3: After adding 22.5 g of calcium oxide to the pre-agglomerates formed in Step 2 under a vortex of 2,000 rpm at 30 degrees Celsius, carbon dioxide was continuously injected into the diluted solution to allow the reaction to proceed until the pH reached 7.0, thereby producing a papermaking filler. Here, the end point of the reaction can be determined as the point where the carbon dioxide injection and discharge rates become equal. At this time, 40 g of heavy calcium carbonate and 40 g of newly formed light calcium carbonate formed a filler (HFCC) attached to the surface of cellulose fibrils.

[0099]

[0100] Example 3. Preparation of paper filler 3

[0101] Step 1-1: To 200 ml of water, 5.6 g of calcium oxide used in Step 1-1 of Example 1, 30 g of heavy calcium carbonate used in Step 1-1 of Example 2, and 2 g of organic fiber were added to prepare a diluted mixture.

[0102] Step 1-2: Grinding was performed using a ball mill as in Step 1-2 of Example 2 above. After grinding, the average width of the cellulose fibrils was confirmed to be 782 nm.

[0103] Step 2: A pre-agglomerate was formed in the same manner as in Step 2 of Example 2 above.

[0104] Step 3: In order to make the total amount of calcium oxide 22.5g in the same manner as Step 3 of the above Example 2, 16.9g of calcium oxide, excluding the 5.6g of calcium oxide added in Step 1-1, was additionally added so that the total amount of calcium oxide became 22.5g, and heavy calcium carbonate was attached to cellulose fibrils together with newly produced light calcium carbonate by blowing carbon dioxide at 30 degrees Celsius to prepare a filler. The purpose of adding calcium oxide in this manner is to maintain an alkaline state during ball milling to help fibrillation of organic fibers.

[0105]

[0106] Example 4. Preparation of paper containing papermaking filler 1

[0107] Step 1: As pulp for making paper, bleached softwood pulp and bleached hardwood pulp were mixed in a ratio of 2:8, and refining was performed to obtain a freeness of 500 ml CSF (Canadian Standard Freeness), and then the papermaking filler and pulp manufactured in Example 1 were mixed in a weight ratio of 25:75.

[0108] Step 2: Using the paper filler and pulp mixed in Step 1, a basis weight of 60 g / m is prepared according to the paper test method (ISO 5269 / 1). 2 The paper was manufactured (Fig. 1).

[0109]

[0110] Example 5. Production of paper containing papermaking filler 2

[0111] In step 1 of the above Example 4, paper was manufactured under the same conditions as in the above Example 4, except that the papermaking filler and pulp manufactured in the above Example 1 were mixed in a weight ratio of 35:65.

[0112]

[0113] Example 6. Production of paper containing papermaking filler 3

[0114] In step 1 of the above Example 4, paper was manufactured under the same conditions as in the above Example 4, except that the papermaking filler manufactured in the above Example 2 was used.

[0115]

[0116] Example 7. Production of paper containing papermaking filler 4

[0117] Paper was manufactured in the same manner as in Example 4, except that in Step 1 of Example 4, the papermaking filler was mixed with the papermaking filler manufactured in Example 2 in a weight ratio of 35:65.

[0118]

[0119] Example 8. Preparation of paper containing papermaking filler 5

[0120] Paper was manufactured in the same manner as in Example 4, except that the papermaking filler used in step 1 of Example 4 was the papermaking filler manufactured in Example 3.

[0121]

[0122] Example 9. Preparation of paper containing papermaking filler 6

[0123] Paper was manufactured in the same manner as in Example 4, except that in Step 1 of Example 4, the papermaking filler was mixed with the papermaking filler manufactured in Example 3 in a weight ratio of 35:65.

[0124]

[0125] Comparative Example 1.

[0126] Step 1: As pulp for manufacturing paper, bleached softwood pulp and bleached hardwood pulp were mixed in a ratio of 2:8 and refined to a freeness of 500 ml CSF (Canadian Standard Freeness).

[0127] Step 2: Mix the filler, heavy calcium carbonate (GCC, Omia Korea, 2-3 μm) and the pulp refined in Step 1 in a weight ratio of 25:75 to obtain a basis weight of 60 g / m according to the paper test method (ISO 5269 / 1). 2 The paper was manufactured.

[0128]

[0129] Comparative Example 2.

[0130] Paper was manufactured under the same conditions as in Comparative Example 1 except that the weight ratio of the filler and pulp was mixed at 35:65 in Step 2 of Comparative Example 1.

[0131]

[0132] Comparative Example 3.

[0133] Paper was manufactured under the same conditions as in Comparative Example 1 except that in Step 2 of Comparative Example 1, light calcium carbonate (PCC, manufactured by Art One Paper, approximately 1.5 μm) was used instead of heavy calcium carbonate.

[0134]

[0135] Comparative Example 4.

[0136] In step 2 of the above Comparative Example 1, instead of using heavy calcium carbonate, light calcium carbonate (PCC, manufactured by Art One Paper, approximately 1.5 μm) was used, and paper was manufactured under the same conditions as in the above Comparative Example 1 except that the weight ratio of filler and pulp was mixed at 35:65 in step 2 of the above Comparative Example 1.

[0137]

[0138] The GCC filler used in the above comparative examples 1 and 2 is a filler mainly used in general white paper factories, and the PCC filler used in comparative examples 3 and 4 is a high-grade filler used to increase bulk and whiteness more than GCC.

[0139]

[0140] Experimental Example 1. Analysis of Paper Characteristics

[0141] In order to analyze the characteristics of paper manufactured including a papermaking filler according to the present invention, the following experiments were conducted.

[0142] (1) Analysis of bulk and heat capacity of paper

[0143] In order to evaluate the effectiveness of the paper manufactured in the examples and comparative examples according to the present invention, the bulk and heat-cutting strength of the manufactured papers were analyzed. The basis weight of the paper manufactured in the examples 4-9 and comparative examples 1 to 4 was 60 g / m. 2 In addition, the bulk and thermal insulation were analyzed. The bulk was the density of the paper (unit: g / cm 3 ) was measured and then the reciprocal was taken (bulk unit cm 3 / g). Tensile strength (unit: km) is the value obtained by dividing the tensile strength (unit: kN / m) by the basis weight of the paper. It is a value that eliminates the influence of basis weight deviation in comparing tensile strengths, so it can be said to be a more reliable value in comparing strengths.

[0144] As a result, as shown in Table 1 below, the bulk of the paper manufactured with GCC (heavy calcium carbonate) in Comparative Examples 1 and 2 was 1.71 and 1.68, respectively, which was much lower than the bulk of 1.86 to 1.92 of the paper manufactured in Examples 4 to 9, which resulted in a very large difference in thickness and flexural rigidity, which are important physical properties of actual paper. In particular, since flexural rigidity is proportional to the cube of the paper thickness, a very large difference occurs in flexural rigidity (Table 1).

[0145] Since the flexural rigidity decreases when the content of the filler is increased, this is an important reason why the content of the filler cannot be increased. However, it was confirmed that the filler according to the present invention exhibits very high flexural rigidity (flexural rigidity of 550 to 680 in Examples 4 to 9; flexural rigidity of 150 to 250 in Comparative Examples 1 and 2).

[0146] In Comparative Examples 3 and 4, the bulk of the paper manufactured using PCC (precipitated calcium carbonate) was 1.84 and 1.83, respectively, which can show a higher bulk than that of heavy calcium carbonate, and it can be seen that the bulk has a similar value to that of Examples 4 to 9.

[0147] However, it can be confirmed that the tensile strength of precipitated calcium carbonate (PCC) is very low compared to Examples 4 to 9 (Table 1 and Fig. 2).

[0148] In addition, as shown in Table 1 below, the heat breaking strength of the paper manufactured using heavy calcium carbonate (GCC) in Comparative Examples 1 and 2 was 2.18 when 25% of the filler was added, and 1.84 when 35% was added. The heat breaking strength of the paper manufactured in Examples 4 to 9 was 3.13 to 3.53 when 25% of the filler was added, and 3.07 to 3.14 when 35% of the filler was added, confirming that the heat breaking strength of Examples 4 to 9 of the present invention was significantly higher under the same filler content compared to Comparative Examples 1 to 2.

[0149] In the case of the heat resistance of paper manufactured using precipitated calcium carbonate (PCC), it was 1.88 when 25% of filler was added, and 1.65 when 35% was added, which was lower than the cases of Examples 4 to 9 or Comparative Examples 1 and 2 using heavy calcium carbonate (GCC) under the same filler content.

[0150] Accordingly, it was confirmed that paper manufactured using the papermaking filler according to the present invention had high bulk and heat-breaking strength. Figure 2 compares the bulk, heat-breaking strength, and internal bonding strength when 25% and 35% of filler were added. It was confirmed that the bulk, heat-breaking strength, and internal bonding strength of Examples 4 to 9 were all higher than when heavy calcium carbonate or light calcium carbonate was used as the filler.

[0151]

[0152] (2) Analysis of whiteness and smoothness of paper

[0153] To evaluate the effectiveness of the paper manufactured in the examples and comparative examples according to the present invention, the whiteness and smoothness of the manufactured papers were analyzed. Specifically, whiteness was measured using the ISO 2470 method, a paper whiteness measurement method, and smoothness was measured using the Beck smoothness method TAPPI T479 cm-99.

[0154] As a result, as disclosed in Table 1 below, Comparative Examples 1 and 2 used heavy calcium carbonate and showed an average whiteness of 86.3%. Comparative Examples 3 and 4 used precipitated calcium carbonate and showed an average whiteness of 88.8%. That is, precipitated calcium carbonate showed a significantly higher whiteness than heavy calcium carbonate. The average whiteness of Examples 4 and 5 was 88.5%, which was higher than that of heavy calcium carbonate and similar to that of precipitated calcium carbonate. However, the average whiteness of Examples 6 and 7 was 87.3%, which was lower than that of the case where only precipitated calcium carbonate was used. The average whiteness of Examples 8 and 9 was 88.8%, which was similar to the whiteness of precipitated calcium carbonate. This result was judged to be due to the effect of precipitated calcium carbonate being mainly synthesized and attached to the surface of the fillers of Examples 8 and 9. In the case of Examples 6 and 7, it was judged to be due to the inclusion of a significant amount of heavy calcium carbonate.

[0155]

[0156] It was found that paper containing HFCC, a papermaking filler according to the present invention, has superior bulk, heat-breaking strength and flexural rigidity than heavy calcium carbonate or light calcium carbonate, and has maintained whiteness and smoothness.

[0157]

[0158] Paper Characteristics Analysis ResultsType of PaperType of FillerFiller:PulpBlendSpecific Whiteness (%)Bulk (cc / g)Heat Breaking Elongation (km)Tensile Strength (kN / m)Smoothness * (sec) Internal bond strength (Ibfft / in2 *1000) Bending stiffness (Gurley unit) Example 4 Example 125: 7588.81.893.452.0312.375.8652.4 Example 5 Example 135: 6588.11.913.131.8413.871.5565.3 Example 6 Example 225: 7587.41.863.131.8515.777.2621.5 Example 7 Example 235: 6587.21.863.071.8115.574.3548.6 Example 8 Example 325: 7588.81.883.532.0814.874.3635.8 Example 9 Example 335:6588.91.893.141.8513.272.1568.2Comparative Example 1 GCC25:7586.21.712.181.2813.468.5245.6Comparative Example 2 GCC35:6586.31.681.841.0812.765.2168.2Comparative Example 3 PCC25:7588.61.841.881.1114.566.3235.6Comparative Example 4 PCC35:6589.11.831.650.9515.862.5142.8

[0159]

[0160] (3) Evaluation of shape and composition of filler

[0161] By observing the intermediate process of forming the fillers for papermaking manufactured in Examples 1 to 3 through an electron microscope, it was possible to confirm the process of forming calcium carbonate by attaching to the central region of multiple fiber fibrils, which is shown in Fig. 3. As shown in Fig. 3, when calcium carbonate is formed in the fiber fibrils, it can be seen that multiple fiber fibrils are involved, and when the calcium carbonate is sufficiently attached, the shape of the fiber fibrils is no longer visible. As a result, it was confirmed that the papermaking fillers manufactured in Examples 1 to 3 had multiple fiber fibrils present in the central region, and that the calcium carbonate was attached to the fiber fibrils.

[0162] In addition, fiber fibril and metal carbonate content were determined by the standard method TAPPI T211 om-02 (Ash in wood, pulp and paperboard: combustion at 525o C) was used to measure the moisture content of the filler sample using the manufactured calcium carbonate metal salt. o Remove from C, measure the total weight (A) and then weigh again 525 o After 1 hour of treatment at C, the mixture was cooled and its weight (B) was measured. At this time, calcium carbonate remains, but all fiber fibrils are removed as water and carbon dioxide. The (AB) value is the weight of fiber fibrils, and B is the weight of calcium carbonate.

[0163] In addition, the fiber fibrils and metal carbonate contents in the fillers manufactured in Examples 1 to 3 were measured, and the results are shown in Table 2 below. The specific gravity of calcium carbonate in the form of calcite is known to be 2.7, and the specific gravity of cellulose is known to be 1.5. Therefore, if the weight of calcium carbonate and fiber fibrils is known, the volume can be calculated.

[0164]

[0165] Fiber fibrils (wt%)Calcium carbonate (wt%)Fiber fibrils (vol%)Calcium carbonate (vol%)Example 13.296.85.694.4Example 24.295.87.392.7Example 33.896.26.693.4

[0166] As can be seen in Table 2 above, it can be seen that Examples 1 to 3 according to the present invention satisfy the content range of fiber fibrils and metal carbonate according to the present invention, and accordingly, it can be seen that the effects of improved bulk, excellent heat resistance, and excellent smoothness can all be simultaneously expressed as shown in Table 1 above.

[0167]

[0168] <Manufacturing Example 1: Manufacturing of ultra-high-filled paper>

[0169] Step 1: As pulp for making ultra-high-filled paper, bleached softwood pulp and bleached hardwood pulp were mixed in a ratio of 5:5, and refining was performed to obtain a freeness of 300 ml CSF (Canadian Standard Freeness), and then the papermaking filler and pulp manufactured in Example 1 were mixed in a weight ratio of 60:40, and this was referred to as 'ultra-high-filled paper 1' stock. In addition, the papermaking filler and pulp were mixed in a weight ratio of 70:30, and this was referred to as 'ultra-high-filled paper 2' stock.

[0170] Step 2: Add 5 wt% of epoxy resin to the solid content of each of the ultra-high-charged battery 1 and ultra-high-charged battery 2 materials mixed in the above step 1, and obtain a basis weight of 60 g / m according to the paper test method (ISO 5269 / 1). 2 Paper was manufactured. The properties of the ultra-high-charged battery manufactured are shown in Table 3 in comparison with the properties of Comparative Example 2. The content of filler included in the paper was calculated by comparing the remaining solid content after reacting the paper at 525 degrees Celsius for 1 hour with the initial paper weight, and is shown as ash in Table 3. The bulk, heat-strength, and smoothness of the ultra-high-charged battery with more than 50% filler added were significantly superior to those of Comparative Example 2. Therefore, it was confirmed that the filler manufactured in Example 1 can be manufactured and used in ultra-high-charged batteries.

[0171]

[0172] - Comparison of properties of ultra-high-capacity batteriesType of paperType of fillerFiller: PulpMixture of ash (wt%)Whiteness (%)Bulk (cc / g)Heat breaking length (km)Tensile strength (kN / m)Smoothness * (sec) Ultra-high-charge battery 1 Example 160: 40 57.58 8.8 1.98 2.45 1.43 42.3 Ultra-high-charge battery 2 Example 170: 30 66.78 9.12 10 2.13 1.25 44.8 Comparative example 2 GCC 35: 65 33.28 6.3 1.68 1.84 1.08 12.7

[0173]

[0174] <Manufacturing Example 2: Composite Manufacturing>

[0175] Step 1: To manufacture a sheet for making a biocomposite, bleached softwood pulp was refined to a CSF (Canadian Standard Freeness) of 300 ml, and then mixed with the papermaking filler manufactured in Example 1 at a weight ratio of 10:90 (refined bleached softwood pulp:filler of Example 1). 8 wt% of epoxy resin was added to the paper stock to obtain a basis weight of 80 g / m2 according to the paper test method (ISO 5269 / 1). 2 A paper sample was manufactured.

[0176] Step 2: After melting the PLA at 220-240 degrees Celsius, apply curtain coating at 350g / m2 on the paper manufactured in Step 1. 2 A 'biocomposite' was manufactured using PLA alone. For comparison, 430 g / m 2 A sheet was manufactured using only PLA without a paper specimen, and was called 'biocomposite PLA'. The nozzle temperature was maintained at 240 degrees Celsius. In the case of the paper specimen, the coating was performed with the temperature increased to 100 degrees Celsius, and a vacuum plate was applied on the opposite side of the coating, and a vacuum of 0.6 atm was maintained to ensure effective internal penetration of the PLA.

[0177] Step 3: The biocomposite was completed after the paper specimen, in which PLA had sufficiently penetrated, was smoothed on the surface using a roller.

[0178] The manufactured biocomposite was weighed and densified at room temperature, and the PLA content was calculated. The weight was measured after 3 hours of treatment at 525°C, and the calcium carbonate content was determined. The tensile strength was also measured, and is shown in Table 4.

[0179] - Physical properties of biocompositesType of paperType of fillerAsh (wt%)Basis weight (g / m) 2 )Tensile strength (MPa)Elongation (%)PLA content (Wt%) Biocomposite Example 117.2433.334.72.381.5 Biocomposite PLA00.1430.00.00.0100.0

[0180] In Table 4, the biocomposite PLA was so brittle that it was impossible to measure its tensile strength. On the other hand, the biocomposite recorded an elongation of 2.3%, which is the strain at which it breaks under tensile force. The biocomposite PLA recorded an elongation of 0.0, indicating that it did not exert any tensile stress. The tensile strength of the biocomposite recorded 34.7 MPa, which was not significantly different from that of a typical PLA composite.

[0181]

[0182] <Manufacturing Example 3: Manufacturing Stone Paper>

[0183] Step 1: To manufacture sheets for making stone paper, bleached softwood pulp was refined to a CSF (Canadian Standard Freeness) of 300 ml, and then mixed with the papermaking filler manufactured in Example 1 at a weight ratio of 10:90 (refined bleached softwood pulp:filler of Example 1). 8 wt% of epoxy resin was added to the paper stock to obtain a basis weight of 80 g / m2 according to the paper test method (ISO 5269 / 1). 2 A paper sample was manufactured.

[0184] Step 2: Density 0.935g / cm 3 After melting the HDPE at 200-220 degrees Celsius, curtain coating was applied at 20g / m on the paper manufactured in step 1. 2 It was carried out in sheep. At this time, the temperature of the paper specimen was raised to 100 degrees Celsius, and a vacuum plate of 0.6 atm was applied to the opposite side of the surface where the coating was applied to ensure effective internal penetration of HDPE.

[0185] Step 3: After the paper specimen with HDPE sufficiently penetrated inside was smoothed on the surface using a roller, the ‘stone paper’ was completed.

[0186]

[0187] The manufactured stone paper was measured for weight and density at room temperature, and the HDPE content was calculated. After treatment at 525°C for 1 hour, the weight was measured to determine the calcium carbonate content. In addition, the tensile strength was measured and is shown in Table 5.

[0188]

[0189] - Comparison of physical properties of stone paper Type of paper Type of filler Ash content (weight%) Basis weight (g / m) 2 )Density (cc / g)Tensile strength (kN / m)HDPE content (Wt%) Stone paper Example 173.2101.30.8852.4618.5 Comparative example 2GCC33.260.20.5951.080.0

[0190]

[0191] Although the embodiments of the present invention have been described above, the spirit of the present invention is not limited to the embodiments presented in this specification, and those skilled in the art who understand the spirit of the present invention will be able to easily propose other embodiments by adding, changing, deleting, or adding components within the scope of the same spirit, but this will also be considered to fall within the spirit of the present invention.

Claims

1. (1) A step of preparing a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10㎛ and fiber fibrils having an average width of 5㎚ to 10㎛ in a weight ratio of 1:5 to 100 and having a solid content of 1 to 60 wt%; (2) a step of adding an ionic polymer to the above mixed aqueous solution and stirring to form a pre-agglomerate; and (3) A method for producing a paper-making filler, comprising the steps of adding 10 to 1000 parts by weight of a calcium compound to 100 parts by weight of an inorganic compound contained in a mixed aqueous solution that forms the above-mentioned pre-agglomerate, and then injecting carbon dioxide until the pH is maintained at 7.0±1.0 at 10 to 80 degrees Celsius to produce a paper-making filler.

2. In paragraph 1, Step (1) above, (1-1) A step of mixing organic fibers and inorganic compounds in a weight ratio of 1:5 to 100, and then adding water to prepare a mixed solution having a solid content of 1 to 60 wt%; and (1-2) A method for producing a paper-making filler, comprising the step of grinding the above-mentioned mixed solution to produce a mixed aqueous solution containing an inorganic compound having an average size of 0.1 to 10 ㎛ and fiber fibrils having an average width of 5 nm to 10 ㎛ in a weight ratio of 1:5 to 100 and having a solid content of 1 to 60 wt%.

3. A method for producing a paper-making filler according to claim 1, wherein the inorganic compound is at least one selected from calcium carbonate (CaCO3), calcium oxide (CaO), calcium hydroxide (Ca(OH)2), magnesium carbonate (MgCO3), gypsum, kaolin, calcined clay, talc, perlite, diatomaceous earth, zinc carbonate, lithium carbonate, magnesium hydroxide, and aluminum trihydrate.

4. A method for producing a paper-making filler, characterized in that in the third paragraph, the calcium carbonate is at least one selected from ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC).

5. A method for producing a paper-making filler, characterized in that in the first paragraph, the fiber fibrils include at least one selected from cellulose and chitin.

6. A method for producing a paper-making filler, characterized in that in paragraph 1, the ionic polymer is at least one selected from an anionic polymer and a cationic polymer.

7. A method for producing a paper-making filler according to claim 6, wherein the anionic polymer is at least one selected from among polysaccharides, proteins, polyvinyl alcohol, polyvinyl acetate, cellulose derivatives, epoxy acrylates, polyesters, polyurethanes, polyester acrylates, polyether acrylates, polyolefin dispersions, polyamides, vinyl copolymers, and polyacrylates.

8. A method for producing a paper-making filler, characterized in that in paragraph 6, the cationic polymer is at least one selected from polyamidoamine-epihalohydrin polymer, polyalkyldiallylamine-epihalohydrin polymer, polyethyleneimine, polyacrylamide, polyamine, polyvinylamine, and cationic starch.

9. A method for producing a paper-making filler, characterized in that in the first paragraph, in the step (2), at least one ionic polymer is added in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the mixed aqueous solution.

10. A method for producing a paper-making filler, characterized in that in the first paragraph, the calcium compound in the step (3) is at least one selected from calcium oxide, calcium hydroxide, calcium sulfate, and calcium phosphate.

11. A plurality of fiber fibrils having an average width of 5 nm to 10 μm are present in the central region, and the metal carbonate has a shape in which the fiber fibrils are arranged on the fiber fibrils. A paper-making filler comprising 1 to 20 volume% of the above fiber fibrils and 80 to 99 volume% of the above metal carbonate. 12.(1) A step of mixing 1 to 60 wt% of the papermaking filler according to Article 11; and 40 to 99 wt% of the refined natural pulp or recycled pulp; and (2) A method for manufacturing paper, comprising: a step of manufacturing paper by putting the mixture of step (1) into a paper machine. 13.(1) A step of mixing 50 to 99 wt% of the papermaking filler according to Article 11; and 1 to 50 wt% of refined natural pulp or recycled pulp; and a step of adding 1 to 30% of an ionic polymer for strength enhancement; and (2) A method for manufacturing ultra-high-filling paper, comprising: a step of introducing the mixture of step (1) into a paper machine to manufacture ultra-high-filling paper having an inorganic material content of 50 wt% or more of the total weight; 14.(1) A step of mixing 50 to 99 wt% of the papermaking filler according to Article 11; and 1 to 40 wt% of the refined natural pulp or recycled pulp; and (2) a step of putting the mixture of step (1) into a paper machine to produce a sheet in the form of paper; and (3) A method for manufacturing a composite, comprising: a step of manufacturing a composite by coating or impregnating 50 to 5,000 parts by weight of a synthetic polymer or biodegradable polymer with respect to 100 parts by weight of the manufactured sheet after the above step (2); 15.(1) A step of mixing 50 to 99 wt% of the papermaking filler according to Article 11 and 1 to 50 wt% of the refined natural pulp or recycled pulp; (2) a step of putting the mixture of step (1) into a paper machine to produce a sheet in the form of paper; and (3) A method for manufacturing stone paper, comprising: after the above step (2), a step of manufacturing stone paper by coating or impregnating 1 to 50 parts by weight of a synthetic polymer or biodegradable polymer with respect to 100 parts by weight of the manufactured sheet; 16. Multiple fiber fibrils with an average width of 5 nm to 10 μm are present in the central region, Metal carbonate is formed by including a filler in the shape arranged on the fiber fibrils, A paper comprising the above filler comprising 1 to 20 volume% of the above fiber fibrils and 80 to 99 volume% of the above metal carbonate.

17. Multiple fiber fibrils with an average width of 5 nm to 10 μm are present in the central region, Metal carbonate is formed by including a filler in the shape arranged on the fiber fibrils, The above filler contains 1 to 20 volume% of the above fiber fibrils and 80 to 99 volume% of the above metal carbonate, Ultra-high-filled paper with inorganic matter accounting for more than 50% of the total weight.

18. Multiple fiber fibrils with an average width of 5 nm to 10 μm are present in the central region, Metal carbonate is formed by including a filler in the shape arranged on the fiber fibrils, A composite comprising the above filler comprising 1 to 20 volume% of the above fiber fibrils and 80 to 99 volume% of the above metal carbonate.

19. Multiple fiber fibrils with an average width of 5 nm to 10 μm are present in the central region, Metal carbonate is formed by including a filler in the shape arranged on the fiber fibrils, The above filler is a stone paper containing 1 to 20 volume% of the above fiber fibrils and 80 to 99 volume% of the above metal carbonate.

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