Method for manufacturing oil absorbent

Abstract

To provide an oil absorbent that can be manufactured in a short time and inexpensively, and a method for manufacturing an oil absorbent.SOLUTION: An oil absorbent includes at least pulverized defective corrugated cardboard, or used corrugated cardboard, or disposal corrugated cardboard, where the corrugated cardboard is one having inner and outer two liners impregnated with wax and a core impregnated with wax sandwiched between both liners, or one impregnated with wax over the approximately entire corrugated cardboard.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an oil adsorbent and a method for manufacturing an oil adsorbent, and in particular to an oil adsorbent that can be manufactured in a short time and at low cost, and a method for manufacturing an oil adsorbent. [Background technology]

[0002] The present applicant previously disclosed an oil adsorbent (see Patent Document 1). This oil adsorbent is produced by immersing waste cardboard in molten wax in a tank, then removing the waste cardboard from the tank and cooling it to coat the entire outer surface of the waste cardboard with wax, and then pulverizing the coated waste cardboard into fibers to produce the oil adsorbent. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 3-44623 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the oil adsorbent, the waste cardboard must be immersed in the molten wax in a tank, and then the waste cardboard must be removed from the tank and cooled to coat the entire outer surface of the waste cardboard with wax, which is a time-consuming and labor-intensive process.

[0005] An object of the present invention is to provide an oil adsorbent and a method for manufacturing an oil adsorbent that have been made in consideration of the above problems. [Means for solving the problem]

[0006] The oil adsorbent described in claim 1 is an oil adsorbent made by crushing at least defective cardboard, used cardboard, or discarded cardboard, wherein the cardboard has two liners, inner and outer, impregnated with wax and a core sandwiched between the liners, also impregnated with wax, or the cardboard is impregnated with wax over substantially the entirety of the cardboard.

[0007] The oil adsorbent according to claim 2 is obtained by pulverizing at least defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper.

[0008] The oil adsorbent according to claim 3 is obtained by pulverizing at least defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added.

[0009] The oil adsorbent according to claim 4 is obtained by pulverizing at least defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength agent and a sizing agent have been added.

[0010] The oil adsorbent according to claim 5 is obtained by crushing at least one of a defective hemp material, a used hemp material, and a discarded hemp material.

[0011] Furthermore, the method for manufacturing an oil adsorbent according to claim 6 is a method for manufacturing an oil adsorbent by crushing at least defective cardboard, used cardboard, or discarded cardboard, wherein the cardboard has two inner and outer liners impregnated with wax and a wax-impregnated core sandwiched between the two liners, or the cardboard is impregnated with wax over substantially the entirety of the cardboard.

[0012] Furthermore, the method for producing an oil adsorbent according to claim 7 is obtained by pulverizing at least defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper.

[0013] Furthermore, the method for producing an oil adsorbent according to claim 8 is obtained by pulverizing at least defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added.

[0014] Furthermore, the method for producing an oil adsorbent according to claim 9 is obtained by pulverizing at least defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength agent and a sizing agent have been added.

[0015] In addition, the method for manufacturing an oil adsorbent according to claim 10 includes at least one that contains defective hemp material, or one that contains used hemp material, or one that contains crushed hemp material for disposal. [Effects of the Invention]

[0016] According to the oil adsorbent of claim 1, the oil adsorbent is made by crushing at least defective cardboard, used cardboard, or cardboard for disposal, wherein the cardboard has two liners (inner and outer) impregnated with wax and a core sandwiched between the liners (wax-impregnated), or the cardboard is impregnated with wax throughout almost the entirety of the cardboard. Therefore, defective cardboard, used cardboard, or cardboard for disposal contains wax, and it is difficult to recycle it as a papermaking raw material; this makes effective use of "cardboard having two liners (inner and outer) impregnated with wax and a core sandwiched between the liners (wax-impregnated)" or "cardboard impregnated with wax throughout almost the entirety of the cardboard." Since there is no need to add new wax during the manufacturing process, the oil adsorbent can be manufactured in a short time and at low cost. When the oil adsorbent is introduced into a mixture of water and oil, it absorbs very little water, and the oil is preferentially adsorbed into the fibers formed by crushing the cardboard and the gaps formed by the fibers.

[0017] Furthermore, according to the oil adsorbent described in claim 2, the adsorbent is made by pulverizing at least wax-impregnated defective paper, wax-impregnated used paper, or wax-impregnated discarded paper. Therefore, wax-impregnated defective paper, wax-impregnated used paper, or wax-impregnated discarded paper contains wax, and this enables effective utilization of "wax-impregnated paper," which is difficult to recycle as a papermaking raw material. Since there is no need to add new wax during the manufacturing process, the adsorbent can be manufactured in a short time and at low cost. When the oil adsorbent is introduced into a mixture of water and oil, it absorbs almost no water, and the oil is preferentially adsorbed into the fibers formed by pulverizing the "wax-impregnated paper" and the gaps between the fibers.

[0018] Furthermore, the oil adsorbent of claim 3 is made by crushing at least defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added. In other words, the added wet strength agent keeps the crushed fibers strong even after the paper is crushed, and the added sizing agent keeps the crushed fibers water-repellent even after the paper is crushed. Therefore, there is no need to add new wax or the like during the manufacturing process, and the oil adsorbent can be manufactured in a short time with reduced costs and resources. When the oil adsorbent is placed into a mixture of water and oil, it absorbs very little water, and oil can be preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by crushing "paper to which a wet strength agent and a sizing agent have been added." Furthermore, the oil adsorbent of the present invention has stronger fibers and wider gaps between the fibers than the fibers of the cardboard that constitutes conventional oil adsorbents, and therefore has improved oil adsorption capacity.

[0019] Furthermore, the oil adsorbent of claim 4 is produced by pulverizing at least defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength agent and a sizing agent have been added. In other words, the added strength agent keeps the pulverized fibers of the unbleached kraft paper strong even after it has been pulverized, and the added sizing agent keeps the pulverized fibers water-repellent even after it has been pulverized. This eliminates the need to add new wax or the like during the manufacturing process, allowing the oil adsorbent to be manufactured in a short time with reduced costs and resources. When the oil adsorbent is introduced into a mixture of water and oil, it absorbs very little water, and oil can be preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by pulverizing "unbleached kraft paper to which a paper strength agent and a sizing agent have been added." Furthermore, the oil adsorbent of the present invention has stronger fibers and wider gaps between the fibers than the fibers of the cardboard that constitutes conventional oil adsorbents, and therefore has improved oil adsorption capacity.

[0020] Furthermore, the oil adsorbent described in claim 5 includes at least materials containing defective hemp materials, materials containing used hemp materials, or crushed materials containing hemp materials for disposal, and therefore aims to make effective use of "materials containing defective hemp materials, materials containing used hemp materials, or materials containing hemp materials for disposal," which are rarely reused; the oil contained in hemp exhibits hydrophobic properties similar to those of wax, so there is no need to add new wax during the manufacturing process, and therefore it can be manufactured in a short time and at low cost; when the oil adsorbent is placed into a mixture of water and oil, it does not absorb much water, and the oil can be preferentially adsorbed into the fibers formed by crushing the "materials containing hemp materials" and the gaps formed by the fibers; and because the oil adsorbent of the present invention uses hemp, which has inherently strong fibers, the fibers are stronger and the gaps between the fibers are wider than the fibers used in the cardboard that makes up conventional oil adsorbents, thereby improving oil adsorption capacity.

[0021] Furthermore, according to the method for producing an oil sorbent as set forth in claim 6, there is provided a method for producing an oil sorbent by crushing at least defective cardboard, used cardboard, or discarded cardboard, wherein the cardboard has two liners, an inner and an outer, that are impregnated with wax, and a wax-impregnated core sandwiched between the two liners, or the cardboard is impregnated with wax throughout almost the entirety of the cardboard. Therefore, defective cardboard, used cardboard, or discarded cardboard contains wax, and it is difficult to recycle it as a papermaking raw material; this method makes effective use of "cardboard having two liners, an inner and an outer, that are impregnated with wax, and a wax-impregnated core sandwiched between the two liners" or "cardboard that is impregnated with wax throughout almost the entirety of the cardboard." Since there is no need to add new wax during the production process, the oil sorbent can be produced in a short time and at low cost; and when the oil sorbent is introduced into a mixture of water and oil, it absorbs very little water, and the oil is preferentially adsorbed into the fibers formed by crushing the cardboard and the gaps formed by the fibers.

[0022] Furthermore, according to the method for producing an oil adsorbent as set forth in claim 7, the adsorbent is produced by pulverizing at least defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper. Therefore, the defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper contains wax, and this enables effective utilization of "wax-impregnated paper," which is difficult to recycle as a papermaking raw material. Since there is no need to add new wax during the production process, the adsorbent can be produced in a short time and at low cost. When the oil adsorbent is introduced into a mixture of water and oil, it absorbs very little water, and the oil is preferentially adsorbed into the fibers formed by pulverizing the "wax-impregnated paper" and the gaps between the fibers.

[0023] Furthermore, according to the method for producing an oil adsorbent as set forth in claim 8, the oil adsorbent is produced by pulverizing at least defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added. In other words, the added wet strength agent keeps the pulverized fibers strong even after the paper is pulverized, and the added sizing agent keeps the pulverized fibers water-repellent even after the paper is pulverized. Therefore, there is no need to add new wax or the like during the production process, and the oil adsorbent can be produced in a short time with reduced costs and resources. When the oil adsorbent is placed into a mixture of water and oil, it absorbs very little water, and oil can be preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by pulverizing "paper to which a wet strength agent and a sizing agent have been added." Furthermore, the oil adsorbent of the present invention has stronger fibers and wider gaps between the fibers than the fibers of the cardboard that constitutes conventional oil adsorbents, and therefore has improved oil adsorption capacity.

[0024] Furthermore, according to the manufacturing method of the oil adsorbent of claim 9, the adsorbent is made by pulverizing at least defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength agent and a sizing agent have been added. In other words, the added paper strength agent keeps the strength of the pulverized fibers even after the unbleached kraft paper is pulverized, and the added sizing agent keeps the water-repellent ability of the pulverized fibers even after the unbleached kraft paper is pulverized. Because there is no need to add new waxes or the like, oil adsorbents can be produced in a short time with reduced costs and resources. When the oil adsorbent is added to a mixture of water and oil, it absorbs almost no water, and the oil is preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by crushing ``unbleached kraft paper with added paper strength agents and sizing agents.'' Furthermore, because the oil adsorbent of the present invention uses unbleached kraft paper, which has inherently strong fibers, the fibers are stronger than the fibers of the cardboard that makes up conventional oil adsorbents, and the gaps between the fibers are wider, thereby improving oil adsorption capacity.

[0025] Furthermore, according to the method for producing an oil adsorbent as set forth in claim 10, the adsorbent is made by crushing at least materials containing defective hemp material, or materials containing used hemp material, or materials containing hemp material to be discarded, and therefore it is possible to make effective use of "materials containing defective hemp material, or materials containing used hemp material, or materials containing hemp material to be discarded," which are rarely reused. In other words, because the oil contained in hemp exhibits water-repellent properties similar to wax, there is no need to add new wax during the manufacturing process, and therefore production can be done in a short time and at low cost. When the oil adsorbent is placed into a mixture of water and oil, it does not absorb much water, and the oil is preferentially adsorbed into the fibers formed by crushing the "material containing hemp material" and the gaps formed by the fibers. Furthermore, since the oil adsorbent of the present invention uses hemp, which has inherently strong fibers, the fibers are stronger and the gaps between the fibers are wider than the fibers of the cardboard that makes up conventional oil adsorbents, and therefore the oil adsorption capacity is improved. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 is a photograph of an oil adsorbent according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] An oil adsorbent and a method for manufacturing an oil adsorbent according to one embodiment of the present invention will now be described.

[0028] (Example 1) When defective cardboard, used cardboard, or cardboard for disposal was crushed The oil adsorbent (the manufacturing method of the oil adsorbent) is at least made by crushing (e.g., crushing into fibers) defective cardboard (e.g., cardboard that cannot be sold due to printing errors, cardboard that is too dirty to be sold, etc.), and the crushing is done, for example, by opening the fibers into fibers with a length of about 0.03 cm to 5 cm using a fiber opener (not shown). The raw material for the oil adsorbent shown in FIG. 1 is not limited to defective cardboard, but may be, for example, used cardboard or cardboard to be discarded (for example, unnecessary cardboard, etc.). The cardboard has two liners, an inner and an outer, impregnated with wax and a core sandwiched between the liners, also impregnated with wax, or the cardboard is impregnated with wax throughout almost the entirety of the cardboard.

[0029] Therefore, according to the oil sorbent (manufacturing method for an oil sorbent) described above, an oil sorbent (manufacturing method for an oil sorbent) is produced by pulverizing at least defective cardboard, used cardboard, or discarded cardboard, and the cardboard has two inner and outer liners impregnated with wax and a wax-impregnated core sandwiched between the liners, or the cardboard is impregnated with wax over substantially the entirety of the cardboard. Therefore, the defective cardboard, used cardboard, or discarded cardboard contains wax, and the manufacturing By making effective use of "cardboard having two inner and outer liners impregnated with wax and a wax-impregnated core sandwiched between the two liners" and "cardboard impregnated with wax throughout," which are difficult to recycle as paper raw materials, and because there is no need to add new wax during the manufacturing process, oil adsorbents can be manufactured in a short time, reducing costs and resources.If the oil adsorbent is added to a mixture of water and oil, it will hardly absorb any water, and the oil will be preferentially adsorbed into the fibers formed by crushing the cardboard and the gaps formed by the fibers.

[0030] Example 2: Grinding of defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper The oil adsorbent (the method for manufacturing the oil adsorbent) is made by pulverizing (e.g., pulverizing into fibers) at least defective wax-impregnated paper (e.g., wax-impregnated paper that has been misprinted and cannot be marketed, or wax-impregnated paper that has been soiled and cannot be marketed), and the pulverization is carried out, for example, by opening the paper into fibers having a length of about 0.03 cm to 5 cm using a fiber opener (not shown). The raw material for the oil adsorbent is not limited to defective wax-impregnated paper (for example, wax-impregnated paper that has been misprinted and cannot be commercialized, or wax-impregnated paper that is soiled and cannot be commercialized), but can also be, for example, used wax-impregnated paper or waste wax-impregnated paper (for example, paper impregnated with unnecessary wax).

[0031] Therefore, according to the above-mentioned oil adsorbent (method for manufacturing an oil adsorbent), the oil adsorbent is made by pulverizing at least defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper. Therefore, the defective wax-impregnated paper, used wax-impregnated paper, or waste wax-impregnated paper contains wax, and since it is possible to make effective use of "wax-impregnated paper," which is difficult to recycle as a papermaking raw material, and there is no need to add new wax during the manufacturing process, it is possible to manufacture an oil adsorbent in a short time, reducing costs and resources. If the oil adsorbent is introduced into a mixture of water and oil, it will hardly absorb any water, and the oil will be preferentially adsorbed into the fibers formed by pulverizing the "wax-impregnated paper" and the gaps formed by the fibers.

[0032] (Example 3) When defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added, is crushed The oil adsorbent (the method for manufacturing the oil adsorbent) is made by pulverizing (e.g., pulverizing into fibers) defective paper to which at least a wet strength agent and a sizing agent have been added (e.g., paper to which a wet strength agent and a sizing agent have been added due to a printing error and which cannot be commercialized, or paper to which a wet strength agent and a sizing agent have been added due to soiling and which cannot be commercialized), and the pulverization is carried out, for example, by opening the paper in a fiber opening machine (not shown) to fiber lengths of, for example, about 0.03 cm to 5 cm. The raw materials for the oil adsorbent are not limited to defective paper to which wet strength agents and sizing agents have been added (for example, paper to which wet strength agents and sizing agents have been added due to printing errors and which cannot be commercialized, or paper to which wet strength agents and sizing agents have been added due to soiling and which cannot be commercialized), but also include, for example, used paper to which wet strength agents and sizing agents have been added, or waste paper to which wet strength agents and sizing agents have been added (for example, paper to which unnecessary wet strength agents and sizing agents have been added). Paper containing wet strength and sizing agents is Cluster-Pak® paper, a packaging material used in beer cartons (multipacks, Cluster-Pak®), which contains water-resistant and water-repellent materials.

[0033] Therefore, according to the oil adsorbent (the manufacturing method of the oil adsorbent), at least defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added are crushed. In other words, defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added, contain the wet strength agent and the sizing agent, and therefore the added wet strength agent remains in the crushed state even after the paper is crushed. The added sizing agent helps the crushed fibers maintain their strength, and the crushed fibers maintain their water-repellent properties even after the paper is crushed. This eliminates the need to add new wax or other additives during the manufacturing process, allowing the oil adsorbent to be manufactured in a short amount of time and at low cost and resource consumption. When the oil adsorbent is placed into a mixture of water and oil, it absorbs very little water, and the oil is preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by crushing the "paper to which a wet strength agent and a sizing agent have been added." Furthermore, the oil adsorbent of this embodiment has stronger fibers and wider gaps between the fibers than the fibers of the cardboard that make up conventional oil adsorbents. This improves the oil adsorption capacity.

[0034] Example 4: In the case of crushing defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper to be discarded to which a paper strength agent and a sizing agent have been added. The oil adsorbent (the method for manufacturing the oil adsorbent) is made by pulverizing (e.g., pulverizing into fibers) defective unbleached kraft paper to which at least a paper strength enhancer and a sizing agent have been added (e.g., unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added due to a printing error and which cannot be commercialized, or unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added due to contamination and which cannot be commercialized), and the pulverization is carried out, for example, by opening the paper in an opening machine (not shown) to fiber lengths of, for example, about 0.03 cm to 5 cm. The raw material for the oil adsorbent is not limited to defective unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added (for example, unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added due to a printing error and which cannot be commercialized, or unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added because it is soiled and cannot be commercialized), but also includes, for example, used unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added, or unbleached kraft paper to be discarded to which a paper strength enhancer and a sizing agent have been added (for example, unbleached kraft paper to which unnecessary paper strength enhancer and a sizing agent have been added). Unbleached kraft paper to which a paper strength agent and a sizing agent have been added is used, for example, for rice and wheat bags, cement bags, etc.

[0035] Therefore, according to the above-mentioned oil adsorbent (the manufacturing method of the oil adsorbent), at least defective unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or used unbleached kraft paper to which a paper strength agent and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength agent and a sizing agent have been added are crushed, so that the added paper strength agent keeps the crushed fibers of the unbleached kraft paper strong even after the unbleached kraft paper is crushed, and the added sizing agent gives the crushed fibers water repellency even after the unbleached kraft paper is crushed. In order to maintain its strength, there is no need to add new wax or the like during the manufacturing process, so the oil adsorbent can be manufactured in a short time with little cost or resource expenditure; if the oil adsorbent is placed into a mixture of water and oil, it will absorb almost no water, and the oil will be preferentially adsorbed in the gaps between the fibers of the oil adsorbent formed by crushing "unbleached kraft paper with added paper strength agents and sizing agents." Furthermore, the oil adsorbent of this embodiment has stronger fibers and wider gaps between the fibers than the fibers of the cardboard that makes up conventional oil adsorbents, thereby improving its oil adsorption capacity.

[0036] (Example 5) When crushing a product containing defective hemp material, a product containing used hemp material, or a product containing hemp material for disposal The oil adsorbent is made by crushing (e.g., crushing into fibers) material that contains at least defective hemp material [for example, material containing hemp material that cannot be commercialized (hemp bags), material containing damaged hemp material (hemp bags), etc.], and the crushing is done, for example, by opening the material into fibers with a fiber length of approximately 0.03 cm to 5 cm using a fiber opener (not shown). The raw materials for oil adsorbents are not limited to those containing defective hemp material (for example, those containing hemp material that cannot be commercialized (hemp bags), those containing damaged hemp material (hemp bags), etc.), but also include, for example, those containing used hemp material or those containing hemp material for disposal (for example, unnecessary hemp bags, etc.). In addition to hemp bags, other items that contain hemp material include hemp clothing and hemp bags.

[0037] Therefore, the oil adsorbent (manufacturing method for oil adsorbents) described above aims to make effective use of "items containing defective hemp material, or items containing used hemp material, or items containing hemp material for disposal," which are rarely reused because they contain at least those containing defective hemp material, or items containing used hemp material, or items containing hemp material for disposal, and in other words, because the oil contained in hemp exhibits water-repellent properties similar to wax, there is no need to add new wax during the manufacturing process, and therefore it can be manufactured in a short time and at low cost, and when the oil adsorbent is placed into a mixture of water and oil, it absorbs almost no water, and the oil is preferentially adsorbed into the fibers formed by crushing the "item containing hemp material" and the gaps formed by the fibers, and furthermore, because the oil adsorbent of this embodiment uses hemp, which has inherently strong fibers, the fibers are stronger and the gaps between the fibers are wider than the fibers of the cardboard that makes up conventional oil adsorbents, and therefore the oil adsorption capacity is improved.

[0038] Example 6 In the above-mentioned Examples 1, 2, 3, 4 and 5, only cardboard, only wax-impregnated paper, only paper to which a wet strength agent and sizing agent have been added, only unbleached kraft paper to which a strength agent and sizing agent have been added, or only materials containing hemp materials were used; however, the present invention is not limited to these and may also be an oil adsorbent comprising a combination of two or more of the following: cardboard crushed into fibers in Example 1; wax-impregnated paper crushed into fibers in Example 2; paper to which a strength agent and sizing agent have been added crushed into fibers in Example 3; unbleached kraft paper to which a strength agent and sizing agent have been added crushed into fibers in Example 4; and material containing hemp materials (for example, hemp bags) crushed into fibers in Example 5. For example, the oil adsorbent may be a combination of 50% by weight of the cardboard of Example 1 crushed into fibers and 50% by weight of a material containing hemp (for example, hemp bags) crushed into fibers. The oil adsorbent of this example also had the same oil adsorbing effect as Examples 1, 2, 3, 4 and 5.

Claims

1. An oil adsorbent made by crushing at least defective cardboard, used cardboard, or discarded cardboard, The corrugated board has two inner and outer liners impregnated with wax and a core sandwiched between the liners and impregnated with wax, or the corrugated board is impregnated with wax over substantially the entirety of the corrugated board. An oil adsorbent characterized by:

2. At least, the paper is made by crushing wax-impregnated defective paper, wax-impregnated used paper, or wax-impregnated waste paper. An oil adsorbent characterized by:

3. At least, the paper is made by crushing defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added. An oil adsorbent characterized by:

4. At least, the paper is made by crushing defective unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added, or used unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength enhancer and a sizing agent have been added. An oil adsorbent characterized by:

5. At least, it is made by crushing a material containing defective hemp material, a material containing used hemp material, or a material containing hemp material for disposal. An oil adsorbent characterized by:

6. A method for producing an oil adsorbent by pulverizing at least defective cardboard, used cardboard, or discarded cardboard, The corrugated board has two inner and outer liners impregnated with wax and a core sandwiched between the liners and impregnated with wax, or the corrugated board is impregnated with wax over substantially the entirety of the corrugated board. A method for producing an oil adsorbent, comprising:

7. At least, the paper is made by crushing wax-impregnated defective paper, wax-impregnated used paper, or wax-impregnated waste paper. A method for producing an oil adsorbent, comprising:

8. At least, the paper is made by crushing defective paper to which a wet strength agent and a sizing agent have been added, or used paper to which a wet strength agent and a sizing agent have been added, or waste paper to which a wet strength agent and a sizing agent have been added. A method for producing an oil adsorbent, comprising:

9. At least, the paper is made by crushing defective unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added, or used unbleached kraft paper to which a paper strength enhancer and a sizing agent have been added, or unbleached kraft paper for disposal to which a paper strength enhancer and a sizing agent have been added. A method for producing an oil adsorbent, comprising:

10. At least, it is made by crushing materials containing defective hemp materials, used hemp materials, or hemp materials for disposal. A method for producing an oil adsorbent, comprising:

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