Foamed paper for oil absorption comprising heat-responsive micro-foaming agent and manufacturing method therefor

Abstract

The present invention relates to a foamed paper for oil adsorption comprising a heat-responsive micro-foaming agent and a manufacturing method therefor and, more specifically, to a foamed paper for oil adsorption comprising a heat-sensitive micro-foaming agent and a manufacturing method thereof, wherein the heat-responsive micro-foaming agent exhibits excellent oil absorption performance and buoyancy performance at the same time by adding a micro-foaming agent and a retention enhancer to cellulose fibers containing lignin during a stock preparation stage of the manufacturing process and then, foaming the micro-foaming agent in a high-temperature drying process. In addition, the present invention relates to a foamed paper for oil adsorption and a manufacturing method thereof, wherein the foamed paper comprises a heat-responsive micro-foaming agent that can be used as a biodegradable adsorbent capable of efficiently absorbing oil in water and seawater in the event of an oil spill accident.

Description

Oil-absorbing foam paper containing a heat-sensitive microfoaming agent and a method for manufacturing the same

[0001] The present invention relates to an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent and a method for manufacturing the same. More specifically, the invention relates to an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent and a method for manufacturing the same, wherein a microfoaming agent and a retention enhancer are added to cellulose fibers containing lignin during the pulp composition stage of the manufacturing process, and the microfoaming agent is foamed during a high-temperature drying process to exhibit excellent oil absorption performance and simultaneous floating performance.

[0002]

[0003] Oil spills frequently occur during the operation of various machinery and equipment used in modern industry. Such oil spills can lead not only to workplace safety issues but also to environmental pollution, including that affecting aquatic ecosystems and coastal environments. To prevent these problems, industrial sites require oil absorbent materials capable of rapidly and efficiently adsorbing and removing spilled oil.

[0004] Conventional oil absorbents used in industrial settings are primarily manufactured based on synthetic fibers or chemical substances. While such absorbents exhibit a certain level of oil absorption performance, they have limitations in that they can have a negative impact on the environment upon disposal. In particular, oil absorbents made from synthetic materials lack biodegradability; consequently, disposal via incineration may lead to long-term adverse environmental effects due to the generation of harmful gases.

[0005] Due to the aforementioned limitations, there is a need to develop an eco-friendly oil absorbent that enables oil adsorption in water through excellent oil adsorption performance while simultaneously exhibiting biodegradability.

[0006]

[0007] To overcome the aforementioned limitations, the present invention aims to provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent that is highly biodegradable, environmentally friendly, and exhibits excellent oil absorption performance through strong lipophilicity and a large surface area, as well as a method for manufacturing the same.

[0008] In addition, the objective of the present invention is to provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent that exhibits high buoyancy due to a pore structure formed by an internal foaming agent and is usable in water, and a method for manufacturing the same.

[0009] In addition, the objective of the present invention is to provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent having excellent mechanical strength and durability, and a method for manufacturing the same.

[0010] The technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description of the present invention.

[0011]

[0012] To achieve the above objective, the present invention provides a foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, comprising: a cellulose fiber containing lignin; and an additive comprising a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent.

[0013] In the present invention, the oil-absorbing foamed paper has a basis weight of 100 to 400 g / m² 2 It is characterized by being.

[0014] In the present invention, the cellulose fiber is characterized by comprising 10 to 30 weight percent of lignin relative to 100 weight percent of the cellulose fiber.

[0015] In the present invention, the cellulose fiber is characterized as being one or more pulp fibers selected from the group consisting of bleached virgin pulp fibers, unbleached virgin pulp fibers, and regenerated pulp fibers.

[0016] In the present invention, the additive is characterized by adding 20 to 50 weight% of the microfoaming agent, 0.02 to 0.6 weight% of the retention enhancer, 0.2 to 0.25 weight% of the inorganic filler, and 0.2 to 1.0 weight% of the sizing agent based on 100 weight% of the dry weight of the cellulose fiber.

[0017] In the present invention, the microfoaming agent is characterized by being one or more selected from the group consisting of water-dispersible acrylic, meta-acrylic, and acrylonitrile-based microfoaming agents and mixtures thereof.

[0018] In the present invention, the microfoaming agent is characterized by being a spherical particle with a diameter of 5 to 20 μm.

[0019] In the present invention, the micro foaming agent is characterized by foaming at 80 to 160 ℃.

[0020] In the present invention, the retention enhancer is characterized by being one or more selected from the group consisting of cationic retention enhancers, anionic retention enhancers, and mixtures thereof.

[0021] In the present invention, the cationic retention enhancer is characterized by being one or more selected from the group consisting of cationic starch, cationic polyacrylamide, polyvinyl amine, and glyoxylated polyacrylamide.

[0022] In the present invention, the anionic retention enhancer is characterized by being one or more selected from the group consisting of anionic polyacryamide and bentonite.

[0023] In the present invention, the sizing agent is characterized by being one or more selected from the group consisting of neutral sizing agents and acidic sizing agents.

[0024] In the present invention, the inorganic filler is characterized as being calcium carbonate.

[0025] The present invention provides a method for manufacturing foamed paper for oil absorption containing a heat-sensitive microfoaming agent, comprising the steps of: dissociating and diluting cellulose fibers containing lignin; refining the diluted fiber suspension; adding and mixing additives including a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent to the refined fiber suspension to prepare a mixture; feeding the mixture to a paper machine to form a sheet and dehydrate it; pressing the sheet; and drying the pressed sheet to foam the microfoaming agent contained in the sheet.

[0026] In the present invention, the cellulose fiber is characterized by comprising 10 to 30 weight percent of lignin relative to 100 weight percent of the cellulose fiber.

[0027] In the present invention, the cellulose fiber is characterized as being one or more pulp fibers selected from the group consisting of bleached virgin pulp fibers, unbleached virgin pulp fibers, and regenerated pulp fibers.

[0028] In the present invention, the step of dissociating and diluting the cellulose fiber is characterized by diluting the cellulose fiber to 3 to 5 weight percent relative to 100 weight percent of the suspension.

[0029] In the present invention, the step of refining the diluted fiber suspension is characterized by refining it to a water content of 300 to 500 mL CSF.

[0030] In the present invention, the step of preparing a mixture by adding and mixing the additives is characterized by adding 20 to 50 weight% of the microfoaming agent, 0.02 to 0.6 weight% of the retention enhancer, 0.2 to 0.25 weight% of the inorganic filler, and 0.2 to 1.0 weight% of the sizing agent relative to 100 weight% of the dry weight of the cellulose fiber.

[0031] In the present invention, the microfoaming agent is characterized by being one or more selected from the group consisting of water-dispersible acrylic, meta-acrylic, and acrylonitrile-based microfoaming agents and mixtures thereof.

[0032] In the present invention, the microfoaming agent is characterized by being a spherical particle with a diameter of 5 to 20 μm.

[0033] In the present invention, the retention enhancer is characterized by being one or more selected from the group consisting of cationic retention enhancers, anionic retention enhancers, and mixtures thereof.

[0034] In the present invention, the cationic retention enhancer is characterized by being one or more selected from the group consisting of cationic starch, cationic polyacrylamide, polyvinyl amine, and glyoxylated polyacrylamide.

[0035] In the present invention, the anionic retention enhancer is characterized by being one or more selected from the group consisting of anionic polyacryamide and bentonite.

[0036] In the present invention, the sizing agent is characterized by being one or more selected from the group consisting of neutral sizing agents and acidic sizing agents.

[0037] In the present invention, the inorganic filler is characterized as being calcium carbonate.

[0038] In the present invention, the step of drying the compressed sheet to foam the microfoaming agent contained in the sheet is characterized by drying at 80 to 160 ℃.

[0039]

[0040] By means of the solution to the above problem, it is possible to provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent that is highly biodegradable, eco-friendly, and exhibits excellent oil absorption performance through strong lipophilicity and a large surface area, and a method for manufacturing the same.

[0041] In addition, the present invention can provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent that exhibits high buoyancy due to a porous structure formed by an internal foaming agent and is usable in water, and a method for manufacturing the same.

[0042] In addition, the present invention can provide an oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent having excellent mechanical strength and durability, and a method for manufacturing the same.

[0043] In addition, the present invention can provide an oil-absorbing foamed paper that can be used as an oil absorbent material capable of minimizing adverse effects on the environment after use, and a method for manufacturing the same.

[0044] In addition, the present invention can provide an oil-absorbing foam paper and a method for manufacturing the same, which exhibit excellent performance even at various temperature and flue levels occurring in marine environments and can be used in various industrial environments such as maritime transport, coastal oil drilling, and coastal facility operation.

[0045] In addition, the present invention can provide an oil-absorbing foam paper capable of providing shock absorption, cushioning performance, heat and sound blocking, and thermal insulation effects, and a method for manufacturing the same.

[0046] In addition, the present invention can provide an oil-absorbing foamed paper that exhibits excellent oil absorption and buoyancy without using a large amount of synthetic material or increasing volume, as in conventional oil absorbents, and a method for manufacturing the same.

[0047] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims.

[0048]

[0049] FIG. 1 is a drawing showing a method for manufacturing foamed paper for oil absorption containing a heat-sensitive microfoaming agent according to the present invention.

[0050] FIG. 2 is a drawing showing SEM images taken at 200x magnification of (a) the surface and (b) the cross-section of foam paper for oil absorption containing a heat-sensitive microfoaming agent according to the present invention.

[0051] FIG. 3 shows (a) absorbent paper, (b) basis weight 100 g / m² of an embodiment and a comparative example according to the present invention. 2 Foamed paper, (c) basis weight 200 g / m² 2 This is a drawing showing the floating test results of foam paper and (d) polypropylene oil-absorbing sheet.

[0052] FIG. 4 shows the absorbent paper of the embodiment and comparative example according to the present invention, basis weight 100 g / m² 2 Foamed paper, basis weight 200 g / m²2 Foamed paper, basis weight 300 g / m² 2 This is a drawing showing the results of measuring the oil absorption capacity of foam paper and polypropylene oil-absorbing sheets.

[0053]

[0054] The terms used in this specification have been selected based on currently widely used general terms whenever possible, taking into account their functions in the present invention; however, these terms may vary depending on the intent of those skilled in the art, case law, the emergence of new technologies, etc. Additionally, in specific cases, terms have been arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the corresponding description of the invention. Therefore, the terms used in this invention should be defined not merely by their names, but based on their meanings and the overall content of the invention.

[0055] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0056] Numerical ranges include the values ​​defined in the above ranges. All maximum numerical limits given throughout this specification include all lower numerical limits as clearly written. All minimum numerical limits given throughout this specification include all higher numerical limits as clearly written. All numerical limits given throughout this specification will include all better numerical ranges within a wider numerical range, as clearly written.

[0057]

[0058] Oil-absorbing foam paper containing a heat-sensitive microfoaming agent

[0059] The present invention relates to foamed paper for oil absorption comprising a heat-sensitive microfoaming agent.

[0060] The present invention relates to foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, comprising: cellulose fibers containing lignin; and additives comprising a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent.

[0061] The above-mentioned foamed paper for oil absorption may be based on fibers containing hydrophobic lignin in hydrophilic cellulose, thereby exhibiting excellent oil absorption, adsorption, and buoyancy simultaneously.

[0062] The above-mentioned foamed paper may exhibit porosity because, at temperatures above an appropriate level, hydrocarbons within the micro-foaming agent expand in volume by up to 40 to 80 times, leaving behind a cavity structure with a shell thickness of approximately 0.05 to 0.5 μm. It may be possible to adsorb and capture oil through the formed cavity structure. The above-mentioned foamed paper has the same basis weight (g / m²). 2 It may have a large bulk and excellent oil adsorption compared to ).

[0063] In addition, the micro foaming agent may foam during the drying process of the paper to form a pore structure within the foamed paper and increase the surface area capable of absorbing oil, thereby providing excellent oil adsorption performance and buoyancy.

[0064] In the present invention, the oil-absorbing foamed paper has a basis weight of 100 to 400 g / m² 2 It may be, preferably 100 to 200 g / m² 2 It may be that the basis weight of the above foamed paper is 100 g / m²2 If it is less than 400 g / m², problems such as reduced tensile strength and durability, and decreased oil adsorption performance may occur, and 400 g / m² 2 If it exceeds [amount], buoyancy is reduced, which may cause problems that make it difficult to use underwater.

[0065] In the present invention, the cellulose fiber may comprise 10 to 30 weight percent of lignin relative to 100 weight percent of the cellulose fiber. If the lignin is included in an amount less than 10 weight percent, a problem may arise in which the oil adsorption capacity of the foamed paper is reduced, and if the lignin is included in an amount exceeding 30 weight percent, a problem may arise in which physical properties including the adsorption structure of the cellulose fiber are damaged.

[0066] In the present invention, the cellulose fiber may be one or more pulp fibers selected from the group consisting of bleached virgin pulp fibers, unbleached virgin pulp fibers, and recycled pulp fibers. The recycled pulp fiber may include recycled paper resources such as newspapers, magazines, and corrugated cardboard, but is not limited thereto.

[0067] In the present invention, the additive may comprise 20 to 50 weight% of the microfoaming agent, 0.02 to 0.6 weight% of the retention enhancer, 0.2 to 0.25 weight% of the inorganic filler, and 0.2 to 1.0 weight% of the sizing agent, based on 100 weight% of the dry weight of the cellulose fiber.

[0068] If the above microfoaming agent is added in an amount of less than 20 weight%, the foaming effect may not be sufficiently exhibited, and if it is added in an amount exceeding 50 weight%, a problem may arise in which the durability of the manufactured foamed paper is reduced. If the above retention enhancer is added in an amount of less than 0.02 weight%, a problem may arise in which the chemical bonding between the cellulose fibers and the microfoaming agent is reduced, and if it is added in an amount exceeding 0.6 weight%, a problem may arise in which the cellulose fibers and the microfoaming agent are excessively aggregated, thereby inhibiting pore formation by the foaming agent. If the above sizing agent is added in an amount of less than 0.2 weight%, a problem may arise in which the durability of the foamed paper is reduced, and if it is added in an amount exceeding 1.0 weight%, a problem may arise in which the sizing effect is reduced due to the sizing agent failing to react with the cellulose fibers.

[0069] In the present invention, the microfoaming agent may be one or more selected from the group consisting of water-dispersible acrylic, methacrylic, and acrylonitrile-based microfoaming agents and mixtures thereof. The hydrophobic shell of the microfoaming agent may improve oil absorption and adsorption performance.

[0070] The above microblowing agent may preferably be an acrylonitrile-based microblowing agent. The acrylonitrile-based microblowing agent may comprise a hydrocarbon compound (blowing agent) that exhibits a foaming effect in a gaseous state, an acrylonitrile-based monomer that encases the hydrocarbon compound in a shell form, and a surfactant that disperses the monomer encaseing the hydrocarbon during emulsion polymerization.

[0071] In the present invention, the micro-foaming agent may be a spherical particle with a diameter of 5 to 20 μm. The micro-foaming agent may expand to 80 to 100 μm after foaming to form many cavities, thereby improving the lightweight performance of the foamed paper. If the diameter is less than 5 μm, a problem may arise in which the absorbency of the oil-absorbing foamed paper is reduced because sufficient pores are not formed, and if it exceeds 20 μm, a problem may arise in which the surface quality of the oil-absorbing foamed paper is degraded and uneven pores are formed within the foamed paper, resulting in a decrease in strength.

[0072] In the present invention, the micro foaming agent may foam at 80 to 160°C, but is not limited thereto. When the micro foaming agent is heated to 80 to 160°C, it may foam up to 4 to 6 times based on the diameter of the micro foaming agent and up to 40 to 60 times based on the volume.

[0073] In the present invention, the retention enhancer may be one or more selected from the group consisting of cationic retention enhancers, anionic retention enhancers, and mixtures thereof. The retention enhancer may enhance the chemical bonding between the cellulose fiber and the microfoaming agent. Using natural and synthetic polymeric retention enhancers widely used in the paper manufacturing process may not only allow the microfoaming agent to be fixed to cellulose fibers having a large number of hydroxyl groups (-OH), but also improve the drying strength of the paper.

[0074] In the present invention, the cationic retention enhancer may be one or more selected from the group consisting of cationic starch, cationic polyacrylamide, polyvinyl amine, and glyoxylated polyacrylamide.

[0075] In the present invention, the anionic retention enhancer may be one or more selected from the group consisting of anionic polyacryamide and bentonite.

[0076] In the present invention, the sizing agent may be one or more selected from the group consisting of neutral sizing agents and acidic sizing agents. The neutral sizing agent may be used when water resistance is required for the foamed paper. The neutral sizing agent may preferably be an alkyl ketene dimer, and the acidic sizing agent may preferably be rosin-alum. The alkyl ketene dimer may impart excellent water repellency, water resistance, and chemical resistance to the foamed paper.

[0077] In the present invention, the inorganic filler may be calcium carbonate, but is not limited thereto. The inorganic filler may impart excellent durability to the foamed paper.

[0078]

[0079] Method for manufacturing oil-absorbing foamed paper containing a heat-sensitive microfoaming agent

[0080] The present invention relates to a method for manufacturing foamed paper for oil absorption comprising a heat-sensitive microfoaming agent.

[0081] The present invention relates to a method for manufacturing foamed paper for oil absorption containing a heat-sensitive microfoaming agent, comprising the steps of: dissociating and diluting cellulose fibers containing lignin; refining the diluted fiber suspension; adding and mixing additives including a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent to the refined fiber suspension to prepare a mixture; feeding the mixture to a paper machine to form a sheet and dehydrate it; pressing the sheet; and drying the pressed sheet to foam the microfoaming agent contained in the sheet.

[0082] The above manufacturing method may be a method for producing oil-absorbing foamed paper that exhibits excellent oil adsorption performance and buoyancy by mixing a micro-foaming agent with a retention enhancer and cellulose fibers during the paper composition process, and then foaming during the paper drying stage to form a pore structure and a large specific surface area within the foamed paper.

[0083] In addition, the micro foaming agent may foam during the drying process of the paper to form a pore structure within the foamed paper and increase the surface area capable of absorbing oil, thereby providing excellent oil adsorption performance and buoyancy.

[0084] The above manufacturing method may be a method for manufacturing foamed paper for oil absorption that simultaneously exhibits excellent oil absorption, adsorption, and buoyancy, based on fibers containing hydrophobic lignin in hydrophilic cellulose.

[0085] The oil-absorbing foamed paper manufactured according to the above-described manufacturing method may be an oil-absorbing foamed paper comprising a thermally responsive microfoaming agent, comprising cellulose fibers containing lignin; and additives including a thermally responsive microfoaming agent, a retention enhancer, and a sizing agent. The foamed paper may exhibit porosity because, at a temperature above an appropriate level, the hydrocarbons inside the microfoaming agent expand in volume by 40 to 80 times and remain as a cavity structure having a shell thickness of approximately 0.05 to 0.5 μm. It may be possible to adsorb and capture oil through the formed cavity structure. The foamed paper has the same basis weight (g / m²). 2 It may have a large bulk and excellent oil adsorption compared to ).

[0086] In the present invention, the cellulose fiber may comprise 10 to 30 weight percent of lignin relative to 100 weight percent of the cellulose fiber. If the lignin is included in an amount less than 10 weight percent, a problem may arise in which the oil adsorption capacity of the foamed paper is reduced, and if the lignin is included in an amount exceeding 30 weight percent, a problem may arise in which physical properties including the adsorption structure of the cellulose fiber are damaged.

[0087] In the present invention, the cellulose fiber may be one or more pulp fibers selected from the group consisting of bleached virgin pulp fibers, unbleached virgin pulp fibers, and recycled pulp fibers. The recycled pulp fiber may include recycled paper resources such as newspapers, magazines, and corrugated cardboard, but is not limited thereto.

[0088] In the present invention, the step of dissociating and diluting the cellulose fiber may be to dilute the cellulose fiber to 3 to 5 weight percent relative to 100 weight percent of the suspension.

[0089] In the present invention, the step of refining the diluted fiber suspension may be to refining it to a CSF of 300 to 500 mL. Through the refining step, the bonding strength between the fibers of the cellulose fiber may be improved. In particular, when recycled pulp fibers are used as raw materials for the foamed paper, since recycling may lead to a decrease in paper strength, it may be necessary to compensate for the decrease in physical strength, such as the refining step or treatment with a dry paper strength enhancer.

[0090] If the above CSF is less than 300 mL, problems may arise such as reduced durability and reduced uniformity of the foamed paper produced by excessively grinding the cellulose fiber length, and if it exceeds 500 mL, problems may arise such as reduced mechanical strength of the foamed paper produced by weakening the bonding force between fibers.

[0091] In the present invention, the step of preparing a mixture by adding and mixing the additives may involve adding 20 to 50 weight% of the microfoaming agent, 0.02 to 0.6 weight% of the retention enhancer, 0.2 to 0.25 weight% of the inorganic filler, and 0.2 to 1.0 weight% of the sizing agent based on 100 weight% of the dry weight of the cellulose fiber.

[0092] If the above microfoaming agent is added in an amount of less than 20 weight%, the foaming effect may not be sufficiently exhibited, and if it is added in an amount exceeding 50 weight%, a problem may arise in which the durability of the manufactured foamed paper is reduced. If the above retention enhancer is added in an amount of less than 0.02 weight%, a problem may arise in which the chemical bonding between the cellulose fibers and the microfoaming agent is reduced, and if it is added in an amount exceeding 0.6 weight%, a problem may arise in which the cellulose fibers and the microfoaming agent are excessively aggregated, thereby inhibiting pore formation by the foaming agent. If the above sizing agent is added in an amount of less than 0.2 weight%, a problem may arise in which the durability of the foamed paper is reduced, and if it is added in an amount exceeding 1.0 weight%, a problem may arise in which the sizing effect is reduced due to the sizing agent failing to react with the cellulose fibers.

[0093] In the present invention, the microfoaming agent may be one or more selected from the group consisting of water-dispersible acrylic, methacrylic, and acrylonitrile-based microfoaming agents and mixtures thereof. The hydrophobic shell of the microfoaming agent may improve oil absorption and adsorption performance.

[0094] The above microblowing agent may preferably be an acrylonitrile-based microblowing agent. The acrylonitrile-based microblowing agent may comprise a hydrocarbon compound (blowing agent) that exhibits a foaming effect in a gaseous state, an acrylonitrile-based monomer that encases the hydrocarbon compound in a shell form, and a surfactant that disperses the monomer encaseing the hydrocarbon during emulsion polymerization.

[0095] In the present invention, the micro-foaming agent may be a spherical particle with a diameter of 5 to 20 μm. The micro-foaming agent may expand to 80 to 100 μm after foaming to form many cavities, thereby improving the lightweight performance of the foamed paper. If the diameter is less than 5 μm, a problem may arise in which the absorbency of the oil-absorbing foamed paper is reduced because sufficient pores are not formed, and if it exceeds 20 μm, a problem may arise in which the surface quality of the oil-absorbing foamed paper is degraded and uneven pores are formed within the foamed paper, resulting in a decrease in strength.

[0096] In the present invention, the retention enhancer may be one or more selected from the group consisting of cationic retention enhancers, anionic retention enhancers, and mixtures thereof. The retention enhancer may enhance the chemical bonding between the cellulose fiber and the microfoaming agent. Using natural and synthetic polymeric retention enhancers widely used in the paper manufacturing process may not only allow the microfoaming agent to be fixed to cellulose fibers having a large number of hydroxyl groups (-OH), but also improve the drying strength of the paper.

[0097] In the present invention, the cationic retention enhancer may be one or more selected from the group consisting of cationic starch, cationic polyacrylamide, polyvinyl amine, and glyoxylated polyacrylamide.

[0098] In the present invention, the anionic retention enhancer may be one or more selected from the group consisting of anionic polyacryamide and bentonite.

[0099] In the present invention, the sizing agent may be one or more selected from the group consisting of neutral sizing agents and acidic sizing agents. The neutral sizing agent may be used when water resistance is required for the foamed paper. The neutral sizing agent may preferably be an alkyl ketene dimer, and the acidic sizing agent may preferably be rosin-alum. The alkyl ketene dimer may impart excellent water repellency, water resistance, and chemical resistance to the foamed paper.

[0100] In the present invention, the sizing agent may be an alkyl ketene dimer. The alkyl ketene dimer may impart excellent water repellency, water resistance, and chemical resistance to the foamed paper.

[0101] In the present invention, the inorganic filler may be calcium carbonate, but is not limited thereto. The inorganic filler may impart excellent durability to the foamed paper.

[0102] In the present invention, the step of drying the compressed sheet to foam the micro-foaming agent contained in the sheet may be performed at 80 to 160°C. If the drying temperature is less than 80°C, a problem may occur in which the micro-foaming agent is not sufficiently foamed, and if it exceeds 160°C, a problem may occur in which the sheet is damaged. Through the drying step, the micro-foaming agent contained in the sheet may be foamed up to 4 to 6 times based on the diameter of the micro-foaming agent and up to 40 to 60 times based on the volume.

[0103]

[0104] Examples

[0105] The embodiments of the present invention are described in detail below, but it is obvious that the present invention is not limited by the following embodiments.

[0106] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described in detail below. However, the present invention is not limited to the embodiments disclosed below but can be implemented in various different forms. The embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0107]

[0108] <Example 1> Basis weight 100 g / m² 2 Oil-absorbing foamed paper containing a heat-sensitive microfoaming agent

[0109] Bleached hardwood kraft pulp containing lignin was fed into a pulper for pulp dissociation, and water was added to dissociate the pulp at a concentration of 3 to 5%. The dissociated pulp suspension was transferred to a disc refiner and refined to a water content of 300 mL, after which the suspension was transferred to a raw material blend chest. To the transferred suspension, additives were added and mixed, comprising 30 wt% of a micro-foaming agent, 0.1 wt% of a cationic retention enhancer, 0.2 wt% of an inorganic filler (calcium carbonate), and 0.4 wt% of an alkyl ketene dimer (AKD) sizing agent, based on 100 wt% of the dry weight of the pulp. The pulp suspension mixed with the additives underwent a sheet-making process, was pressed, transferred to a drying device at a temperature of 80 to 160 ℃, and dried to allow the micro-foaming agent to foam, resulting in a basis weight of 100 g / m². 2 Foamed paper containing a heat-sensitive microfoaming agent was manufactured.

[0110]

[0111] <Example 2> Basis weight 200 g / m² 2 Oil-absorbing foamed paper containing a heat-sensitive microfoaming agent

[0112] Basis weight 200 g / m² 2 Except for controlling it to this extent, the basis weight 200 g / m² was obtained in the same manner as in Example 1 above. 2 Foamed paper for oil absorption containing a thermally sensitive microfoaming agent was manufactured.

[0113]

[0114] <Example 3> Basis weight 300 g / m² 2 Oil-absorbing foamed paper containing a heat-sensitive microfoaming agent

[0115] Basis weight 300 g / m² 2 A basis weight of 300 g / m² was obtained in the same manner as in Example 1 above, except that it was controlled to be such. 2 Foamed paper for oil absorption containing a thermally sensitive microfoaming agent was manufactured.

[0116]

[0117] <Comparative Example 1> Cellulose pulp fiber absorbent paper

[0118] Composed solely of cellulose pulp fibers, basis weight 300 g / m² 2 Absorbent paper was manufactured.

[0119]

[0120] <Comparative Example 2> Polypropylene (PP) oil-absorbing sheet

[0121] Basis weight 78 g / m² 2 A polypropylene (PP) oil-absorbing sheet was prepared.

[0122]

[0123] <Experimental Example 1> SEM Analysis of Surface and Cross-section of Oil-Absorbing Foamed Paper

[0124] The surface and cross-section of the foamed paper prepared in Example 1 above were photographed and analyzed using a scanning electron microscope (SEM) at 200x magnification, and the results are shown in Figure 2.

[0125] As shown in Fig. 2 (a), the surface of the oil-absorbing foamed paper of Example 1 was found to have foamed micro-foaming agent particles contained between the cellulose fibers.

[0126] In addition, as shown in Fig. 2 (b), in the cross-section of the oil-absorbing foamed paper of Example 1, it was found that the honeycomb-shaped cavities formed by the foamed micro-foaming agents were regular.

[0127] Through the above results, it was confirmed that the oil-absorbing foamed paper containing a heat-sensitive microfoaming agent according to the present invention has microfoaming agents bonded between cellulose fibers, and that the microfoaming agent foams to form a large surface area and cavities.

[0128]

[0129] <Experimental Example 2> Analysis of Floating Characteristics of Oil-Absorbing Foamed Paper

[0130] The foamed paper prepared in Examples 1 and 2, the absorbent paper of Comparative Example 1, and the polypropylene (PP) oil-absorbing sheet of Comparative Example 2 were prepared as specimens of 5 × 5 cm size, and then each was placed in a beaker containing 125 mL each of gasoline and distilled water to analyze the floating characteristics, and the results are shown in Figure 3.

[0131] As shown in Fig. 3 (a), the absorbent paper made solely of cellulose pulp fibers of Comparative Example 1 sank immediately upon being placed in gasoline and distilled water and did not exhibit any floating properties.

[0132] In addition, as shown in Fig. 3 (d), the oil-absorbing sheet made of polypropylene of Comparative Example 2 floated in distilled water, but in gasoline, it rapidly absorbed gasoline and sank due to its own weight.

[0133] On the other hand, as shown in Figures 2 (b) and (c), the oil-absorbing foam paper of Examples 1 and 2 was found to float on the surface of both gasoline and distilled water.

[0134] Through the above results, it was confirmed that the oil-absorbing foamed paper containing a heat-sensitive microfoaming agent according to the present invention exhibits excellent buoyancy, thereby enabling its use in water, including seas, rivers, and oceans.

[0135]

[0136] <Experimental Example 3> Measurement of Oil Absorption Capacity of Oil-Absorbing Foamed Paper

[0137] The foamed paper prepared in Examples 1 to 3, the absorbent paper of Comparative Example 1, and the polypropylene (PP) oil-absorbing sheet of Comparative Example 2 were prepared as specimens of size 5 × 5 cm, placed in a beaker containing 125 mL of gasoline, and removed after 30 seconds. Subsequently, the difference in weight before and after oil absorption was measured to calculate the amount of oil absorbed per unit weight of pulp, and the results are shown in Figure 4.

[0138] As shown in Fig. 4, the absorbent paper of Comparative Example 1 showed a very low oil absorption of about 0.8 g / g, whereas the oil-absorbing foamed paper of Example 1 and the foamed paper of Example 2 showed very high oil absorption compared to Comparative Example 1, with oil absorption of 3.1 g / g and 4.0 g / g, respectively.

[0139] The polypropylene oil-absorbing sheet of Comparative Example 2 above exhibited a high oil absorption capacity of 4.4 g / g, whereas the basis weight of Example 3 above was 300 g / m² 2 It was confirmed that the oil-absorbing foamed paper exhibited an oil absorption capacity of 6.3 g / g and showed superior oil absorption characteristics compared to the polypropylene oil-absorbing sheet through its high basis weight.

[0140] Through the above results, it was confirmed that the oil-absorbing foamed paper containing the heat-sensitive microfoaming agent according to the present invention exhibits excellent oil absorption.

[0141]

[0142] The oil-absorbing foam paper according to the present invention exhibits excellent oil absorption and buoyancy, and can be utilized as an oil-absorbing material capable of rapidly responding to oil spill accidents that may occur in rivers and oceans. It can also be effectively used for preventing oil spills and for regular maintenance in chemical processes at refineries and other industrial facilities, and thus can be widely utilized in various industrial fields.

[0143] Furthermore, by incorporating cellulose fiber-based eco-friendly materials, the environmental impact upon disposal can be minimized, which is expected to contribute to the mitigation of environmental pollution issues and thus contribute to sustainable industrial operations.

Claims

1. Cellulose fibers containing lignin; and Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, an additive comprising a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent.

2. In Paragraph 1, The above oil-absorbing foam paper, Basis weight 100 to 400 g / m² 2 Foam paper for oil absorption containing a heat-sensitive microfoaming agent, characterized by being.

3. In Paragraph 1, The above cellulose fibers are, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, characterized by comprising 10 to 30 weight percent of the lignin relative to 100 weight percent of the cellulose fiber.

4. In Paragraph 1, The above cellulose fibers are, Oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent, characterized by being one or more pulp fibers selected from the group consisting of bleached virgin pulp fibers, unbleached virgin pulp fibers, and recycled pulp fibers.

5. In Paragraph 1, The above additive is, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, characterized by adding 20 to 50 weight% of the microfoaming agent, 0.02 to 0.6 weight% of the retention enhancer, 0.2 to 0.25 weight% of an inorganic filler, and 0.2 to 1.0 weight% of a sizing agent based on 100 weight% of the dry weight of the cellulose fiber.

6. In Paragraph 1, The above microfoaming agent is, Foam paper for oil absorption comprising a heat-sensitive microfoaming agent, characterized by being one or more selected from the group consisting of water-dispersible acrylic, meta-acrylic, and acrylonitrile-based microfoaming agents and mixtures thereof.

7. In Paragraph 1, The above microfoaming agent is, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent characterized by being spherical particles with a diameter of 5 to 20 μm.

8. In Paragraph 1, The above microfoaming agent is, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent, characterized by foaming at 80 to 160 ℃.

9. In Paragraph 1, The above retention enhancer is, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent characterized by being one or more selected from the group consisting of cationic retention enhancers, anionic retention enhancers, and mixtures thereof.

10. In Paragraph 9, The above-mentioned cationic retention enhancer is, Foamed paper for oil absorption comprising a heat-sensitive microfoaming agent characterized by being one or more selected from the group consisting of cationic starch, cationic polyacrylamide, polyvinylamine, and glyoxylated polyacrylamide.

11. In Paragraph 9, The above-mentioned anionic retention enhancer is, Oil-absorbing foamed paper comprising a heat-sensitive microfoaming agent, characterized by being one or more selected from the group consisting of anionic polyacryamide and bentonite.

12. In Paragraph 1, The above size system is, Foam paper for oil absorption comprising a heat-sensitive microfoaming agent characterized by one or more selected from the group consisting of neutral sizing agents and acid sizing agents.

13. In Paragraph 1, The above inorganic filler is, Foam paper for oil absorption containing a heat-sensitive microfoaming agent characterized by being calcium carbonate.

14. A step of dissociating and diluting cellulose fibers containing lignin; A step of refining the above diluted fiber suspension; A step of preparing a mixture by adding and mixing an additive comprising a heat-sensitive microfoaming agent, a retention enhancer, an inorganic filler, and a sizing agent to the above-mentioned refined fiber suspension; A step of feeding the above mixture to a paper machine to form it into a sheet and dehydrate it; Step of compressing the above sheet; and A method for manufacturing foamed paper for oil absorption containing a heat-sensitive microfoaming agent, comprising the step of drying the compressed sheet to foam the microfoaming agent contained in the sheet.

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