Paper-containing structure and method for manufacturing paper-containing structure

Abstract

In this paper-containing structure, a paper-containing sheet (2) has a first surface (1a) and a second surface (1b), a first hydroxyl group high-concentration region (11) is formed on the first surface (1a), and a second hydroxyl group high-concentration region (14) is formed on the second surface (1b). A tensile stress is generated in each of the hydroxyl group high-concentration regions (11, 14), and the tensile stress is balanced with the deformation resistance of the paper-containing sheet (2) to form a first stable state and maintain the first shape. When the paper-containing structure (1) is in the second shape, the force is balanced to form a second stable state, and the second shape is maintained. The paper-containing structure (1) switches the first shape and the second shape in at least one direction by applying a trigger force.

Description

Technical Field

[0001] This invention relates to a paper-containing structure whose three-dimensional shape changes when a triggering force is applied, and a method for manufacturing the paper-containing structure.

[0002] This application claims priority based on Japanese Patent Application No. 2022-166403, filed in Japan on October 17, 2022, the contents of which are incorporated herein by reference. Background Technology

[0003] Origami has the advantage of being able to create various three-dimensional structures by folding a single sheet of paper. By studying folding patterns, its unfolding and folding functions can be repeatedly utilized, or it can form structures with high mechanical strength. Therefore, its applications are anticipated in various fields. For example, origami is envisioned for use in the manufacture of three-dimensional electronic devices, the production of lightweight and inexpensive impact-absorbing materials, and the space-saving benefits of sheet folding.

[0004] In this process, autonomous paper bending technology, which involves applying some external force to the paper to make it bend itself, has attracted much attention. This technology is sometimes referred to as "self-folding." With the development of such autonomous paper bending technology, significant progress is expected in utilizing the properties of origami.

[0005] As such bending technology, techniques have been reported to date that involve pre-configuring a material on paper that responds to external stimuli, and then using the response of this material when a stimulus is applied to cause the paper to bend autonomously. Examples of stimuli include electric current and heat.

[0006] However, this bending technology requires the supply of certain energy sources such as electricity and heat, which may limit its application environment. Furthermore, the paper also needs to be modified with special materials, resulting in high costs.

[0007] As a solution to this problem, a method is disclosed that uses an inkjet printer to spray an aqueous solution containing 2-propanol onto paper and then dries it (see Non-Patent Document 1). This method does not require supplying the paper with energy such as current or heat, and has the advantage of not requiring the use of special materials to modify the paper.

[0008] Existing technical documents

[0009] Non-patent literature

[0010] Non-patent literature 1: Hiroki Shigemune, Shingo Maeda, Yusuke Hara, and Shuji Hashimoto. "Design of paper mechatronics: Towards a fully printed robot" Proceedings of 2014 IEEE / RSJ International Conference on Intelligent Robots and Systems (IROS 2014) Summary of the Invention

[0011] (a) Technical problems to be solved

[0012] The method disclosed in Non-Patent Document 1 is useful in terms of solving the problems of other methods to date, but further improvements are expected for application in the manufacture of practical three-dimensional structures.

[0013] The objective of this invention is to provide a novel paper-containing structure with high practicality utilizing origami technology and a method for manufacturing the same.

[0014] (II) Technical Solution

[0015] The present invention provides the following methods.

[0016] [1] A paper-containing structure is formed from a paper-containing sheet in a dry state containing paper. The paper-containing sheet has a first surface and a second surface that are mutually opposite to each other. A first high-hydroxyl concentration region is formed on the first surface, where the density of hydroxyl groups is higher than that of other parts of the first surface. A second high-hydroxyl concentration region is formed on the second surface, where the density of hydroxyl groups is higher than that of other parts of the second surface. Tensile stress is generated in the first high-hydroxyl concentration region and the second high-hydroxyl concentration region, respectively. The tensile stress in the first high-hydroxyl concentration region of the first surface and the tensile stress in the second high-hydroxyl concentration region of the second surface are balanced with the deformation resistance of the paper-containing sheet when the paper-containing structure is in a first shape, forming a first stable state that can maintain the first shape. In addition, when the paper-containing structure is in a second shape, it is also balanced with the deformation resistance of the paper-containing sheet to form a second stable state that can maintain the second shape. The paper-containing structure can switch the first shape and the second shape in at least one direction by applying a triggering force to a portion thereof.

[0017] According to method [1], by applying a triggering force to a portion of a paper-containing structure having a first high-hydroxyl concentration region and a second high-hydroxyl concentration region, the antagonistic balance between tensile stress and deformation resistance within the paper-containing structure changes, switching between the first shape and the second shape in at least one direction. Through this switching action, various functions such as holding, storing, opening and closing, moving, and valve opening and closing of items can be realized.

[0018] [2] In the paper-containing structure of the first method 1, in the first high-hydroxyl concentration region and the second high-hydroxyl concentration region, by using a wavenumber of 3331 cm⁻¹ -1 In the infrared total internal reflection measurement method, where infrared light is reflected from the surface of the paper-containing structure to measure the infrared absorption spectrum of that surface, the infrared transmittance can be lower than that of other areas. At a wavenumber of 3331 cm⁻¹... -1 In this case, it most sensitively reflects changes in hydroxyl concentration. The infrared transmittance of the high hydroxyl concentration region is not limited, and can be more than 0.01%, more than 0.1%, more than 0.5%, more than 1%, more than 2%, more than 3%, more than 4%, more than 5%, or more than 10% lower than the other regions.

[0019] [3] In the paper-containing structure described in method 1 or 2, one or more notches may be formed on the paper-containing sheet, through which the first stable state and the second stable state can be formed. A triggering force may also be applied to the notch.

[0020] [4] In any of the paper-containing structures described in methods 1-3, the triggering force may be generated by water penetration into the paper-containing structure, changes in humidity of the environment in which the paper-containing structure is placed, local compression of the paper-containing structure, heating of the paper-containing structure, cooling of the paper-containing structure, cutting of a portion of the paper-containing structure, or applying an external force to the paper-containing structure. The triggering force is a stimulus to the paper-containing sheet, which may be a force applied to the paper-containing sheet or a force generated inside the paper-containing sheet. For example, it may also be a local temperature change of the paper-containing sheet caused by strong light irradiation, a bullet impact, a portion of the paper-containing sheet being burned off by a laser beam, vibration of the paper-containing sheet caused by sound waves, or pressure applied to the paper-containing sheet by air or wind.

[0021] [5] In any of the paper-containing structures in methods 1-4, the paper-containing structure may switch between the first shape and the second shape bidirectionally by applying the triggering force to a portion thereof. The method and type of application of the triggering force may also be different in the case of changing from the first shape to the second shape and in the case of changing from the second shape to the first shape. A third shape or a fourth shape may also be present.

[0022] [6] A gripping member having a paper-containing structure of any one of the methods 1-5, for gripping an article, wherein the first shape is an article release shape with an open end, and the second shape is an article gripping shape with the end narrowed, wherein the triggering force is generated by the gripping member colliding with the article or by the gripping member contacting a support surface supporting the article, thereby the paper-containing structure changes from the article release shape to the article gripping shape to grip the article. The end can be set to match the position of the article to be gripped, and can be the lower end, side end, or upper end of the paper-containing sheet.

[0023] [7] A gripper for a drone, comprising the gripper described in embodiment 6, wherein the gripper has a fixing portion at its central portion that is fixed to a support portion of the drone. In the case of a drone, the gripper is lightweight and does not have a separate opening and closing mechanism, which are significant advantages. It can also accommodate ultra-small drones. Furthermore, the gripper for a drone of the present invention can also change from a second shape to a first shape, gripping an item to a destination, and releasing or placing the item from the drone at the destination.

[0024] [8] A cushioning material comprising a paper-containing structure as described in any one of embodiments 1-5, for arranging one or more articles therein, wherein the paper-containing structure may have an origami structure, the first shape being a folded, reduced shape of the paper-containing structure without a bag, or the paper-containing structure being a flat, flat shape without a bag, and the second shape being an unfolded shape of the paper-containing structure forming one or more bags, the shape changing from the reduced shape or flat shape to the unfolded shape by applying a triggering force to a portion of the paper-containing structure. In this case, the paper-containing sheet may, for example, be folded into a Miura fold shape or an egg carton shape after printing the first and second high-hydroxyl concentration areas into a desired pattern, or have creases. The bag may have a honeycomb structure.

[0025] [9] A paper-folding device comprising: a paper-containing structure as described in any one of embodiments 1-5, and at least one of an electronic component and wiring disposed on at least one of the first and second surfaces of the paper-containing structure. The electronic component may be an active component or a component composed of active components (transistor, IC, diode, operational amplifier, etc.), or a passive component such as a resistor, coil, or capacitor, or a printed antenna, relay, switch, connector, printed circuit board, terminal, etc. The wiring may be, for example, wiring formed by thinly printing copper or aluminum onto a paper-containing sheet. The paper-containing sheet may also be deformed between a first shape and a second shape by applying a triggering force to the paper-containing sheet through a heating element or solenoid.

[0026]

[10] A cushioning material having a paper-containing structure described in any one of the methods 1-5 for arranging one or more articles therein may have a paper-containing structure having a folding structure, a first shape being a flat shape in which the paper-containing structure is unfolded without having a bag, and a second shape being an unfolded shape in which the paper-containing structure is folded to form one or more bags, and changing from the flat shape to the unfolded shape by applying a triggering force to a portion of the paper-containing structure.

[0027]

[11] A cushioning material comprising a paper-containing structure as described in any one of embodiments 1-5 may have one or more openings and a first high-hydroxyl concentration region and a second high-hydroxyl concentration region disposed around the openings. The first shape is a reduced shape of the paper-containing structure folded without a bag or a flat shape of the paper-containing structure unfolded. The second shape is a three-dimensional shape of the paper-containing structure having a cylindrical wall portion and a support portion, wherein the cylindrical wall portion stands upright at the periphery of the openings, and the support portion extends from the cylindrical wall portion, changing from the reduced shape or flat shape to the three-dimensional shape by applying a triggering force to a portion of the paper-containing structure. The cylindrical wall portion and the support portion may integrally have a honeycomb structure.

[0028]

[12] A method for manufacturing a paper-containing structure, wherein the paper-containing structure is manufactured in any one of the methods 1-5, comprises the following steps: applying a liquid containing water to the portions of the first and second surfaces of the paper-containing sheet where the first high-hydroxyl concentration region and the second high-hydroxyl concentration region are to be formed; and drying the liquid.

[0029]

[13] In any of the paper-containing structures described in methods 1-5, at least a portion of at least one of the first and second surfaces of the paper-containing sheet may be adhered with a flexible protective film. By covering at least a portion of the paper-containing sheet with the protective film in this way, especially forming a protective film at the part in contact with water, unwanted water will not penetrate into the paper-containing sheet, thus maintaining the deformation function of the paper-containing sheet caused by the first and second high-hydroxyl concentration regions. In addition, when holding items with high water content such as fruits by means of the paper-containing structure, by forming a protective film at the part in contact with the item, it is also possible to prevent the paper-containing structure from absorbing water from the item, thus maintaining the water content of the fruit, etc. Furthermore, in the part whose surface is covered by the protective film, the coefficient of friction of the surface in contact with the fruit, etc., increases, thus improving the positional stability of the item in the stored state.

[0030]

[14] In any of the paper-containing structures described in methods 1-5, a flexible protective film may be attached to the first and second surfaces of the paper-containing sheet, respectively. Thus, by sandwiching the paper-containing sheet with the protective film, even if the paper-containing structure 1 is placed in a humid or high-humidity environment, unwanted moisture will not penetrate the paper-containing sheet, maintaining the deformation function of the paper-containing sheet caused by the high concentration regions of the first and second hydroxyl groups. Furthermore, when holding items with high moisture content, such as fruits, with the paper-containing structure, it is also possible to prevent the paper-containing structure from absorbing moisture from the items. Therefore, the water content of fruits, etc., can be maintained. Furthermore, by covering the surface with the protective film, the coefficient of friction of the surface in contact with fruits, etc., increases, thereby improving the positional stability of the items in the storage state. Alternatively, the end face of the paper-containing sheet may be covered with the material of the protective film to form an end face protective film. In this case, moisture resistance can be further improved, and the protective film can be prevented from peeling off from the end face.

[0031] (III) Beneficial Effects

[0032] According to the present invention, by applying a triggering force to a portion of a paper-containing structure having a first high-hydroxyl concentration region and a second high-hydroxyl concentration region, the antagonistic balance between tensile stress and resistance to deformation within the paper-containing structure changes, switching between a first shape and a second shape in at least one direction. Various functions can be achieved through this switching action. Attached Figure Description

[0033] Figure 1A This is an enlarged cross-sectional view used to illustrate the principle of the paper-containing structure of the present invention.

[0034] Figure 1B This is an enlarged cross-sectional view used to illustrate the principle of the paper-containing structure of the present invention.

[0035] Figure 1C This is an enlarged cross-sectional view used to illustrate the principle of the paper-containing structure of the present invention.

[0036] Figure 2 This is an enlarged cross-sectional view used to illustrate the principle of the paper-containing structure of the present invention.

[0037] Figure 3 This is a cross-sectional enlarged view showing an example of a region with high hydroxyl concentration in this invention.

[0038] Figure 4A This is a magnified cross-sectional view illustrating the role of the high-hydroxyl concentration region in this invention.

[0039] Figure 4B This is a magnified cross-sectional view illustrating the role of the high-hydroxyl concentration region in this invention.

[0040] Figure 5 This is a cross-sectional view of a method for measuring the concentration of hydroxyl groups.

[0041] Figure 6 This is a graph used to illustrate the high concentration region of hydroxyl groups in this invention.

[0042] Figure 7 This is a graph used to illustrate the high concentration region of hydroxyl groups in this invention.

[0043] Figure 8 This is a graph used to illustrate the high concentration region of hydroxyl groups in this invention.

[0044] Figure 9 This is a graph used to illustrate the high concentration region of hydroxyl groups in this invention.

[0045] Figure 10 This is a perspective view showing one embodiment of the paper-containing structure of the present invention.

[0046] Figure 11 This is a top view showing one embodiment of the paper-containing structure of the present invention.

[0047] Figure 12 This is a perspective view showing one embodiment of the paper-containing structure of the present invention.

[0048] Figure 13 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0049] Figure 14 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0050] Figure 15 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0051] Figure 16This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0052] Figure 17A This is a cross-sectional view illustrating the operation of other embodiments of the present invention.

[0053] Figure 17B This is a cross-sectional view illustrating the operation of other embodiments of the present invention.

[0054] Figure 18 This is a top view of a test piece illustrating an embodiment of the present invention.

[0055] Figure 19 It means that it was used Figure 18 The curves showing the test results of the movement and load of the test piece.

[0056] Figure 20 It means that it was used Figure 18 The graph shows the changes in the thickness and angle of the paper in the test piece.

[0057] Figure 21 It means that it was used Figure 18 A graph showing the changes in the horizontal printing width and angle of the test piece.

[0058] Figure 22 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0059] Figure 23 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0060] Figure 24 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0061] Figure 25 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0062] Figure 26 This is a front view showing another embodiment of the paper-containing structure of the present invention.

[0063] Figure 27 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0064] Figure 28 This is a front view showing the article release state of a drone-mounted clamp, which is another embodiment of the paper-containing structure of the present invention.

[0065] Figure 29 This is a front view showing the article holding state of a drone-mounted clamp, which is another embodiment of the paper-containing structure of the present invention.

[0066] Figure 30 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0067] Figure 31 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0068] Figure 32 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0069] Figure 33 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0070] Figure 34 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0071] Figure 35 This is a front view showing another embodiment of the paper-containing structure of the present invention.

[0072] Figure 36 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0073] Figure 37 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0074] Figure 38 This is a top view showing another embodiment of the paper-containing structure of the present invention.

[0075] Figure 39 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0076] Figure 40 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0077] Figure 41 This is a perspective view showing another embodiment of the paper-containing structure of the present invention.

[0078] Figure 42 This is an enlarged cross-sectional view showing another embodiment of the paper-containing structure of the present invention.

[0079] Figure 43 This is an enlarged cross-sectional view showing another embodiment of the paper-containing structure of the present invention.

[0080] Figure 44 This is an enlarged cross-sectional view showing another embodiment of the paper-containing structure of the present invention.

[0081] Figure 45 This is an enlarged cross-sectional view showing another embodiment of the paper-containing structure of the present invention.

[0082] Figure 46 This is a top view showing a sensing pad as another embodiment of the paper-containing structure of the present invention.

[0083] Figure 47 This is a three-dimensional view showing the sensor pad fixed to the human head.

[0084] Figure 48 This is a top view showing a partial cross-section of the absorbent pad, which is another embodiment of the paper-containing structure of the present invention.

[0085] Figure 49 This is a cross-sectional view of the absorbent pad.

[0086] Figure 50 This is a top view showing a conical structure as another embodiment of the paper-containing structure of the present invention.

[0087] Figure 51 This is a frontal photograph showing the state before the triggering force is applied to the conical structure.

[0088] Figure 52 This is a frontal photograph showing the state of the conical structure after a triggering force has been applied.

[0089] Figure 53 This is a cross-sectional view showing a catalyst unit as another embodiment of the paper-containing structure of the present invention.

[0090] Figure 54 This is a photograph of the cushioning material without a protective film before deformation, which is another embodiment of the paper-containing structure of the present invention.

[0091] Figure 55 This is a photograph of the cushioning material after deformation without the protective film.

[0092] Figure 56 This is a photograph of a cushioning material with a protective film before deformation, which is another embodiment of the paper-containing structure of the present invention.

[0093] Figure 57 This is a photograph of the cushioning material with the protective film after deformation.

[0094] Figure 58 This is a photograph illustrating the use of the cushioning material with the protective film.

[0095] Figure 59 This is an explanatory diagram illustrating the moisture absorption test method that investigated the difference in moisture absorption between paper sheets without and with a protective film.

[0096] Figure 60 It is a graph representing the results of the moisture absorption experiment. Detailed Implementation

[0097] Hereinafter, embodiments of the paper-containing structure and the method for manufacturing the paper-containing structure of the present invention will be described with reference to the accompanying drawings.

[0098] Figures 1A to 1C This is an enlarged cross-sectional view used to illustrate the operating principle of the present invention. For example... Figures 1A to 1C As shown, the paper-containing structure of the present invention is formed from a paper-containing sheet 2 in a dry state containing paper. The paper-containing sheet 2 has a first surface 1a and a second surface 1b that are mutually opposite surfaces. On the first surface 1a, a first hydroxyl high concentration region 11 is formed by allowing a liquid 9 consisting of water or an aqueous solution to permeate a portion of the paper-containing sheet 2, thereby forming a first hydroxyl high concentration region 11 where the hydroxyl density is higher than that of other parts of the first surface 1a. A second hydroxyl high concentration region (not shown) is also formed on the second surface 1b where the hydroxyl density is higher than that of other parts of the second surface 1b.

[0099] Tensile stresses are generated in the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region, respectively, in directions parallel to the paper sheet 2. The tensile stresses in the first high-hydroxyl concentration region 11 of the first surface 1a, the tensile stresses in the second high-hydroxyl concentration region of the second surface 1b, and the deformation resistance of the paper sheet 2 itself antagonize each other to form a first stable state when the paper structure 1 is in the first shape, thus maintaining the first shape. Furthermore, they antagonize each other to form a second stable state when the paper structure 1 is in the second shape, thus maintaining the second shape. Moreover, the present invention is characterized in that the first shape and the second shape can be switched in at least one direction by applying a triggering force to a portion of the paper structure 1.

[0100] like Figure 1A As shown, water 9 adheres to the first surface 1a of the paper sheet 2 and permeates to form a first high-hydroxyl concentration region 11. Considering the thickness T1 of the paper sheet 2, an appropriate amount of water 9, which will not be excessive, adheres to the first surface 1a. Thus, as... Figure 1B and Figure 1C As shown, water 9 permeates from the first surface 1a into the paper sheet 2. Figure 1B The paper sheet 2 swells slightly due to the penetration of water 9, causing the first surface 1a to become convex, thus warping the paper sheet 2. Typically, after this state, when the water 9 evaporates, as... Figure 1C As shown, the warp is eliminated, and residual tensile stress remains in the first hydroxyl high concentration region 11.

[0101] like Figure 2As shown, water 9 can permeate from the first surface 1a to the second surface 1b. In this case, a first high-hydroxyl concentration region with a wide width or a high hydroxyl concentration is formed on the first surface 1a, and a second high-hydroxyl concentration region with a narrow width or a low hydroxyl concentration is formed on the second surface 1b.

[0102] like Figure 3 As shown, a first high-hydroxyl concentration region 12, where water 9 does not penetrate from the first surface 1a to the second surface 1b, and a first high-hydroxyl concentration region 13, where water 9 penetrates from the first surface 1a to the second surface 1b, can also be formed. In this case, a difference in tensile stress between the first surface 1a side and the second surface 1b side is also generated, which can achieve the effect of the present invention.

[0103] Paper sheet 2 is a sheet made of paper itself (i.e., a paper sheet) or a sheet with paper as its main component, containing cellulose as its main component. As a paper sheet, a relatively thick paper such as tracing paper is preferred, and paper in which the cellulose fibers are compressed into bundles during the manufacturing process is even more preferred.

[0104] Sheets with paper as the main component may contain paper and other components. These other components can be selected arbitrarily according to the purpose, without impairing the effects of the invention. Specifically, examples of these other components include cosmetics such as resins, silicone, calcium carbonate, and clay, gloss agents, starch, and adhesives such as PVA.

[0105] When applying water 9 to the paper sheet 2, not only pure water can be used, but also aqueous solutions containing various water-soluble compounds, or aqueous solutions containing small amounts of organic solvents such as alcohols, can be used. In this case, the solute in the aqueous solution can penetrate and remain on the paper sheet 2. Examples of solutes in the aqueous solution include organic solvents (2-propanol, ethylene glycol, etc.) used to adjust the viscosity and surface tension of inkjet inks, electrolytes such as various salts, and dyes. The aqueous solution can contain only one type of solute or two or more types. For example, by adding dye, it is possible to obtain the advantage that the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 are easily visually identifiable.

[0106] The lower the concentration of components other than water in the aqueous solution, the better. For example, it is preferred to be 5% or less by mass of the total liquid, more preferably 3% or less by mass, and even more preferably 1% or less by mass.

[0107] Non-Patent Document 1 discloses a technique for autonomously bending a paper sheet using an aqueous solution containing water and 2-propanol at a mass ratio of 90:10 (water:2-propanol = 90:10). However, while lower alcohols like 2-propanol are fully miscible with water, they do not have the ability to autonomously bend paper sheets, or if they do, it is significantly less effective than water. Therefore, when comparing the same amounts, the autonomous deformation of the paper sheet is slower and remains at a small bending angle when using an aqueous solution containing 2-propanol compared to using pure water, where the liquid component is mostly water.

[0108] In contrast, the paper-containing structure and its manufacturing method of the present invention, compared with the use of an aqueous solution containing a high concentration of 2-propanol, can achieve autonomous deformation of the paper-containing sheet at a faster speed and a larger bending angle, which has a significant effect. However, the liquid used in the manufacturing method of the paper-containing structure according to the embodiments of the present invention can be any liquid as long as it is at a low concentration. In the manufacturing method of the paper-containing structure according to the embodiments of the present invention, an aqueous solution containing 2-propanol can also be used as long as it is at the low concentration as described above.

[0109] In the aforementioned process, when water or an aqueous solution is applied to and permeates the paper sheet 2, two aqueous solutions with different concentrations of the additive may be applied to different areas of the paper sheet 2. The solute is not particularly limited as long as it is water-soluble and can be chosen arbitrarily. The aqueous solution is preferably neutral.

[0110] In the solute, the salt can be either an organic salt or an inorganic salt, preferably an inorganic salt. Examples of such inorganic salts include alkali metal chlorides such as lithium chloride (LiCl, hydration parameter: 7.1), sodium chloride (NaCl, hydration parameter: 3.5), potassium chloride (KCl, hydration parameter: 1.9), and rubidium chloride (RbCl, hydration parameter: 1.2); alkali metal bromides such as lithium bromide (LiBr, hydration parameter: 7.6), sodium bromide (NaBr, hydration parameter: 4.2), potassium bromide (KBr, hydration parameter: 2.1), and rubidium bromide (RbBr, hydration parameter: 0.9); alkali metal bromides such as lithium iodide (LiI, hydration parameter: 9.0), sodium iodide (NaI, hydration parameter: 5.5), potassium iodide (KI, hydration parameter: 2.5), and rubidium iodide (RbI, hydration parameter: 0.6); and magnesium chloride (MgCl2, hydration parameter: 13.7), calcium chloride (C... Chlorides of Group II metals such as aCl2 (hydration parameter: 12.0), strontium chloride (SrCl2, hydration parameter: 10.7); bromides of Group II metals such as magnesium bromide (MgBr2, hydration parameter: 17.0), calcium bromide (CaBr2, hydration parameter: 14.6), strontium bromide (SrBr2, hydration parameter: 12.7); iodides of Group II metals such as magnesium iodide (MgI2, hydration parameter: 19.0), calcium iodide (CaI2, hydration parameter: 17.0), strontium iodide (SrI2, hydration parameter: 15.5); chlorides of transition metals such as manganese chloride (MnCl2, hydration parameter: 11.0), ferrous chloride (FeCl2, hydration parameter: 12.0), cobalt chloride (CoCl2, hydration parameter: 13.0), and nickel chloride (NiCl2, hydration parameter: 13.0).

[0111] By adding the solute as described above to the paper sheet 2, the penetration and drying of water 9 in the aqueous solution can be suppressed. When the suppression effect is small, a solute with a hydration parameter of 0.5 to 9 can be selected; to increase the suppression effect, a solute with a hydration parameter of 15 to 20 can be selected, but this is not limited in this invention.

[0112] There is no limitation on the temperature at which water 9 adheres to and permeates the paper sheet 2; for example, it can be 10~35°C. Under such temperature conditions, water 9 can permeate the paper sheet 2 more effectively.

[0113] The relative humidity at which water 9 adheres to and permeates the paper sheet 2 is preferably 10-80%, for example, it can be any one of 20-65% and 20-40%. Under such relative humidity conditions, water 9 can permeate the paper sheet 2 more effectively.

[0114] After the infiltration process, the paper sheet 2, which has an internal water concentration gradient 9, is dried. When the paper sheet 2, which has a water concentration gradient, is dried, for example... Figure 4A As shown, in the portion 11 containing water 9, the cellulose in the paper sheet 2 shrinks, generating tensile stress. Consequently, the first surface 1a is bent into a concave shape. If drying is performed, the bending angle increases. Figure 4B As shown, a three-dimensional structure 10 is formed in the state after drying. If the paper sheet 2 is dried while suppressing this deformation, tensile stress can be generated in the high hydroxyl concentration region of the paper sheet 2.

[0115] In the paper-containing sheet 2, cellulose molecules are bonded to each other through hydrogen bonds. It is speculated that if water 9 permeates into the paper-containing sheet 2, the first surface 1a will expand, but in the paper-containing sheet 2, water molecules break the hydrogen bonds between cellulose molecules, becoming water molecules in a state between cellulose molecules, forming intermolecular bonds of cellulose molecule-water molecule-cellulose molecule.

[0116] Paper sheet 2 is manufactured by clamping pulp with pressure rollers to allow water to drip off, and then applying pressure and heating simultaneously. Due to this manufacturing method, paper sheet 2 is initially in a state of compressive strain due to external force. If such paper sheet 2 is permeated with water 9 and dried, as the water 9 in paper sheet 2 decreases due to drying, cellulose molecules in paper sheet 2 are re-bonded to each other through hydrogen bonds. At this point, compared to the initial state, the strain of paper sheet 2 is reduced or eliminated, becoming a stable state, and it is presumed that it has shrunk compared to before the permeation of water 9. It is presumed that the shrinkage force generated at this time, such as... Figure 4B As shown, the paper sheet 2 can bend autonomously in the region of high hydroxyl concentration.

[0117] The formation of the first and second water concentration gradients in the paper sheet 2 is not limited in this invention, but printing using an inkjet printer is preferred for coating complex shapes. When using an inkjet printer, a liquid consisting of water or an aqueous solution is ejected from the inkjet printer onto the paper sheet 2, allowing it to adhere to and penetrate the paper sheet.

[0118] [Method for measuring the density of hydroxyl groups]

[0119] Figure 5This describes the measurement principle of the total internal reflection (ATR) method used to measure the density of hydroxyl groups. A transparent crystal 15, serving as an optical waveguide, is placed on a paper sheet 2, which is used as the sample. Infrared light is incident through this crystal 15 while continuously changing the wavelength, irradiating a region of depth dp in the surface layer of the paper sheet 2 from the lower surface of the crystal 15. The reflected light that penetrates into the interior of the paper sheet 2 and is reflected back through the crystal 15 is then incident on a light-receiving sensor. The transmittance of the incident light for each wavenumber is determined by the light-receiving sensor. In the figure, θ is the angle of incidence, which is set to 45° in this specification. The penetration depth dp that produces the reflected light also varies depending on the sample, and is approximately in the range of 0.5 to 5 μm. The actual measurement device used is a Fourier transform infrared spectrophotometer manufactured by Shimadzu Corporation, trade name "IRAffinity-S", with the measurement conditions set to a resolution of 4 cm⁻¹. -1 Apodization function (the function used in Fourier transform): Happ-Genzel; Total number of iterations: 30.

[0120] Figure 6 and Figure 7 Indicates passage Figure 5 An example of data obtained using the ATR method. Figures 6-9 This represents the transmittance (%) spectra obtained by continuously changing the wavenumber of infrared radiation on the surface of the paper sheet 2 before water penetration, the surface of the paper sheet 2 after printing water drying, and the back side of the paper sheet 2. As shown in these graphs, at a wavenumber of 3331 (cm²), -1 Before and after ( ), a significant decrease in transmittance occurs due to the high density of hydroxyl groups, resulting in a downward peak. Therefore, it is proven that by measuring wavenumber 3331 (cm²), -1 By comparing the transmittance under different conditions, the density of hydroxyl groups in the surface layer of the paper sheet 2 can be compared.

[0121] then, Figure 8 and Figure 9This indicates the results of comparative experiments conducted to confirm whether the reduction in infrared transmittance of the paper sheet 2 was caused by other factors. In these comparative experiments, the infrared spectra of the surface and back sides of the paper sheets that underwent four different treatments were measured while the wavenumber of the infrared light was continuously varied. "Water surface" refers to the measurement result of the surface after water is printed on the surface of the paper sheet 2 and then dried; "Water back" refers to the measurement result of the back after water is printed on the surface of the paper sheet 2 and then dried; "Die back" refers to the measurement result of the back of the paper sheet 2 after being stamped with a load of 1 ton / (40mm×40mm); "Die surface" refers to the measurement result of the surface of the same paper sheet 2 after stamping; "Compression back" refers to the measurement result of the back of the paper sheet 2 after being stamped with a load of 3 ton / (40mm×40mm) through an aluminum block; "Compression surface" refers to the measurement result of the surface of the same paper sheet 2 after being stamped through an aluminum block; "Hand-folded back" refers to the measurement result of the surface when the crease is placed into the paper sheet 2 by hand; "Hand-woven surface" refers to the measurement result of the back when the crease is placed into the paper sheet 2 by hand. As shown in these graphs, at a wavenumber of 3331 (cm -1 Before and after (the curve shows the change in transmittance), the significant decrease in transmittance due to the high density of hydroxyl groups only occurred at the "water surface." Therefore, it is proven that the decrease in transmittance caused by the concentration of hydroxyl groups is a result of water permeation.

[0122] [First Implementation Method]

[0123] Figures 10-12 This describes a paper-containing structure 20, which is a specific first embodiment of the paper-containing structure of the present invention. In this paper-containing structure 20, a first high-hydroxyl concentration region 11 extending in the short-side direction is formed at the center of the width direction of the first surface 1a of the rectangular paper-containing sheet 2 by printing with water or an aqueous solution. Furthermore, on the second surface 1b of the paper-containing sheet 2, a second high-hydroxyl concentration region 14 is formed at a certain distance from both ends of the long side by printing with water or an aqueous solution. Moreover, the paper-containing sheet 2 is thoroughly dried. At the center of both ends of the first high-hydroxyl concentration region 11 in the length direction, as shown... Figure 11 As shown, the paper sheet 2 can also be cut intermittently in a dotted line shape, or a shallow weakening line 22 can be pre-formed into the paper sheet 2. The length of the weakening line 22 can be such that it reaches or does not reach the high concentration region 14 of the second hydroxyl group.

[0124] Furthermore, the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 also include cases where the hydroxyl concentration is not constant in the horizontal and / or thickness directions of the paper sheet 2 (i.e., a gradient exists). A concentration gradient can be formed in the thickness direction with diffusion; therefore, if coating is typically performed from one side only, a gradient can be formed. For ease of explanation, the long and short sides have been described above, but they can also be reversed. Additionally, the paper sheet 2 can be square, or it can be any shape such as circular, elliptical, triangular, pentagonal, or irregular. The shapes of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 can also be non-straight strips; they can be curves, discontinuous dashed lines, intersecting at acute or obtuse angles instead of being orthogonal, or their width varying along the length direction of the first and second high-hydroxyl concentration regions 11 and 14. Regarding other embodiments, unless specifically mentioned, the above points are common.

[0125] The paper sheet 2, after the drying process, is bent along the upper fold line 5 by tensile stress that reduces in the width direction generated inside the second high hydroxyl concentration region 14, with both ends concave along the second surface 1b. On the other hand, although tensile stress that reduces in the width direction of the first high hydroxyl concentration region 11 is also generated inside the first high hydroxyl concentration region 11, since the second high hydroxyl concentration region 14 bends first, the resistance to deformation of the paper sheet 2 is higher than the force that bends the paper sheet 2 along the long side direction, and almost no deformation occurs due to the tensile stress of the second high hydroxyl concentration region 14. Thus, in Figure 10 Under the first shape shown where the long sides are respectively bent, the tensile stress of the first high hydroxyl concentration region 11, the tensile stress of the second high hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 counteract each other to maintain a stable shape.

[0126] Next, regarding the Figure 10A force is applied to the center of the first surface 1a of the first shape-stable paper-containing structure 20, or cuts 21 are made at both ends of the first high-hydroxyl concentration region 11, or both, or it is cut open in the presence of a weakening line 22. As a result, the resistance to deformation of the paper-containing sheet 2 decreases because the cuts 21 are formed orthogonal to the second high-hydroxyl concentration region 14, or because the width of the second high-hydroxyl concentration region 14 is reduced by the cuts 21. Therefore, due to the tensile stress caused by the first high-hydroxyl concentration region 11, the paper-containing sheet 2 bends along the width direction of the first high-hydroxyl concentration region 11, deforming into a V-shaped cross-section concave towards the first surface 1a, and stops while maintaining this second shape. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the resistance to deformation of the paper-containing sheet 2 are balanced, and no further deformation occurs.

[0127] Therefore, according to the paper-containing structure 20, in Figure 10 In the first shape shown, a pressing force is applied to the central portion of the first surface 1a, or cuts 21 are made at both ends of the first hydroxyl high concentration region 11, or both, or it is cut open in the presence of a weakening line 22, thereby changing it into Figure 12 The second shape shown allows it to perform various functions during the process. For example, the paper-containing structure 20 is V-shaped in the second shape, which allows it to hold other items, perform certain switching operations at the moving end, or press other items by utilizing the increased overall thickness of the paper-containing structure 20.

[0128] In addition, the paper-containing structure 20 can be easily and cost-effectively formed by coating the paper-containing sheet 2 with water or an aqueous solution and then drying it. Its size can also be varied, and it is lightweight, so it can be used for a wide variety of applications.

[0129] Furthermore, while the above description uses a pressing force as the triggering force, in this invention, the triggering force can also be generated by water seeping into the paper-containing structure, changes in humidity of the environment in which the paper-containing structure is placed, local compression of the paper-containing structure, heating of the paper-containing structure, cooling of the paper-containing structure, cutting of a portion of the paper-containing structure, or applying an external force from other directions to the paper-containing structure. This is also the case in the following embodiments.

[0130] [Second Implementation]

[0131] Figures 13-15 This refers to a paper-containing structure 30, which is a second embodiment of the paper-containing structure of the present invention. In this paper-containing structure 30, a first high-hydroxyl concentration region 11 extending along the short side is formed at the center of the first surface 1a of the rectangular paper sheet 2 in the width direction by printing with water or an aqueous solution. Figure 14 As shown, on the second surface 1b of the paper sheet 2, from the two corners of one short side toward the center of the other short side, a second high-hydroxyl concentration region 14, which appears as a V-shape and is in the form of strips when viewed from above, is formed by printing with water or an aqueous solution. Furthermore, the paper sheet 2 is thoroughly dried.

[0132] In this paper-containing structure 30, an upper bend line 5 is pre-formed along the center of the width direction of the second high-hydroxyl concentration region 14. Additionally, a lower bend line 6 is formed along the center of the width direction of the first high-hydroxyl concentration region 11 and then extends flat. In this state, the lower bend line 6 is almost invisible.

[0133] The paper sheet 2, having undergone the drying process, is bent into a V-shape by the upper bending line 5, with both ends concave along the second hydroxyl high concentration region 14 and the second surface 1b side, due to the tensile stress generated inside the second hydroxyl high concentration region 14 that reduces its width. On the other hand, tensile stress that reduces its width is also generated inside the first hydroxyl high concentration region 11, but since the paper sheet 2 is first bent into a V-shape by the upper bending line 5, its resistance to deformation relative to the force that bends the paper sheet 2 along its long side is higher, and deformation caused by the tensile stress in the second hydroxyl high concentration region 14 is almost non-existent. Thus, as... Figure 13 As shown, the V-shaped upper bends 5, when viewed from above, are stabilized by a first shape with a V-shaped cross-section.

[0134] Next, through the analysis of... Figure 13 A force is applied to the center of the first surface 1a of the first shape-stable paper-containing structure 20, such as... Figure 15 As shown, the paper sheet 2 is bent along the hidden lower fold line 6, with the upper fold line 5 bending in the center. Consequently, the resistance to deformation caused by the upper fold line 5 weakens, while the tensile stress caused by the high hydroxyl concentration region 11 is greater, causing the paper sheet 2 to deform into a V-shaped cross-section concave towards the first surface 1a. Then, maintaining... Figure 15 It stops at the second shape shown. Figure 15 In the second shape shown, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation will occur.

[0135] Therefore, according to the paper-containing structure 30, in Figure 13 In the first shape shown, by applying a pressing force to the central portion of the first surface 1a, it can be easily transformed into... Figure 15The second shape shown can achieve various functions in this process. For example, by forming a V-shape with the paper-containing structure 30, it can clamp other items, perform opening and closing operations, or press other items by increasing the thickness of the paper-containing structure 30. The cross-sections of the upper bend line 5 and the lower bend line 6 do not have to be V-shaped as shown in the figure; they can be gently bent into a U-shape.

[0136] Furthermore, for ease of explanation, the long and short sides of the paper-containing sheet 2 are described as above in the paper-containing structure 30, but the long and short sides can be opposite, or they can be square. The paper-containing sheet 2 can be any shape, such as circular, elliptical, triangular, pentagonal, or irregular. The shapes of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 do not have to be straight strips; they can be curves, or shapes whose width varies along the length of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14.

[0137] [Third Implementation Method]

[0138] Figure 16 , Figure 17A as well as Figure 17B This describes a paper-containing structure 40, which is a third embodiment of the paper-containing structure of the present invention. In this paper-containing structure 40, a first high-hydroxyl concentration zone 11 extending in the short-side direction is formed on the first surface 1a of the rectangular paper-containing sheet 2 by printing with water or an aqueous solution. Furthermore, a second high-hydroxyl concentration zone 14 is formed on the second surface 1b of the paper-containing sheet 2 by printing with water or an aqueous solution. This second high-hydroxyl concentration zone 14 connects the two ends of each long side, forming a semi-circular or semi-elliptical shape passing through the center of the paper-containing sheet 2. Moreover, the paper-containing sheet 2 is thoroughly dried.

[0139] In this paper-containing structure 40, an upper fold line 5 with a small radius of curvature is formed in advance along the second high-hydroxyl concentration region 14 using a die-stamping process or the like. However, in this invention, this stamping process is not necessary and can be performed even when the coating is dry. Additionally, a lower fold line 6 is formed along the center of the width direction of the first high-hydroxyl concentration region 11 and extends flat. In this state, the lower fold line 6 is almost invisible. Furthermore, creases may occur depending on the type of printing press or the printing sequence, but due to the high resistance to deformation, bending is prevented, so a flat state can be formed even without re-flattening after printing. In this case, a flattening process is not required. Whether the state becomes flat or creases are formed after printing is influenced by the design (thickness, curvature, etc.) of the printing lines on the first surface 1a and the second surface 1b of the paper sheet 2, and should therefore be set individually. This is also true in the following embodiments.

[0140] The paper sheet 2, after the drying process, is subjected to tensile stress that reduces its width direction within the second high hydroxyl concentration region 14. This stress further reduces the radius of curvature by applying force to the upper bend line 5, and the paper sheet 2 bends with a smaller curvature, bounded by the upper bend line 5. On the other hand, although tensile stress that reduces its width direction is also generated within the first high hydroxyl concentration region 11, the paper sheet 2 bends first along the semi-circular or semi-arc-shaped upper bend line 5. Therefore, the resistance to deformation of the paper sheet 2 relative to the force bending the paper sheet 2 along its long side is higher, and deformation caused by the tensile stress in the second high hydroxyl concentration region 14 does not occur. Thus, as... Figure 17A As shown, Figure 13 The upper bending lines 5 shown protrude toward the first surface 1a, stabilizing the first dome-shaped first shape with the central part of the paper sheet 2 bulging.

[0141] Next, through the analysis of... Figure 16 A force is applied to the center of the first surface 1a of the first shape-stable paper-containing structure 40, such as... Figure 17A and Figure 17B As shown, the paper sheet 2 is bent with the hidden lower fold line 6 as the boundary, and the upper fold line 5 bends in the center. The deformation resistance caused by the upper fold line 5 is weakened, and the tensile stress caused by the first high hydroxyl concentration region 11 is greater. The paper sheet 2 is deformed by concave (warping upward) towards the first surface 1a. Then, it is held... Figure 17B The process stops at the second shape shown. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation occurs.

[0142] Therefore, according to the paper-containing structure 40, in Figure 16 In the first shape shown, by applying a pressing force to the central portion of the first surface 1a, it changes to... Figure 17B The second shape shown can achieve various functions in this process. For example, by having the paper-containing structure 40 form a V-shape in the second shape, it can hold other items, perform switching operations, or allow other items to descend due to the reduced height of the dome of the paper-containing structure 30.

[0143] Furthermore, for ease of explanation, the long and short sides of the paper-containing sheet 2 are described as above in the paper-containing structure 40, but the long and short sides can be opposite, or they can be square. The paper-containing sheet 2 can be any shape, such as circular, elliptical, triangular, pentagonal, or irregular. It can also be a shape in which the width changes along the length direction of the first high hydroxyl concentration region 11 and the second high hydroxyl concentration region 14.

[0144] Figure 18This is a test piece used to confirm the effects of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 in the third embodiment described above. A strip-shaped first high-hydroxyl concentration region 11 extending in the short side direction is formed on the first surface 1a of a rectangular paper sheet 2 by printing with water or an aqueous solution. A strip-shaped first high-hydroxyl concentration region 14 is formed on the second surface 1b of the paper sheet 2 by printing with water or an aqueous solution. This first high-hydroxyl concentration region 14 connects the two ends of each long side, forming a semi-circle or semi-ellipse shape passing near the center of the paper sheet 2. An upper fold line 5 with a small radius of curvature is formed beforehand along the center of the width direction of the second high-hydroxyl concentration region 14 using a die-stamping process. Furthermore, the paper sheet 2 is thoroughly dried. Additionally, a lower fold line 6 is formed once along the center of the width direction of the first high-hydroxyl concentration region 11 and extends flatly. In this state, the lower fold line 6 is almost invisible. In this embodiment, if the surface is flat after printing, re-stamping is not required.

[0145] The length r1 of the perpendicular line from the center of the second high-hydroxyl concentration region 14 to the long side of the paper sheet 2 is set to 24 mm, and the length r2, half the length of the long side of the paper sheet 2, is set to 15 mm. The paper sheet 2 is commercially available tracing paper with a thickness of 39.5 kg, 56.0 kg, and 88.0 kg per ream (1000 sheets). The width of the second high-hydroxyl concentration region 14 is set to 2 mm.

[0146] First, using commercially available tracing paper with a full-size ream (1000 sheets) weighing 56.0 kg, the narrowest width W of the two high-concentration second hydroxyl regions 14 was changed to 10 mm, 20 mm, 30 mm, and 40 mm, respectively, to manufacture paper-containing structures 50. These paper-containing structures 50 have a dome-shaped first shape. The pressure change was recorded while pressing down on the center P of these dome-shaped paper-containing sheets 2 with a measuring instrument. The results are as follows... Figure 19 The graph is shown below.

[0147] like Figure 19 As shown, when the distance between the curves is 30 mm, a larger peak occurs than in the cases of 10 mm, 20 mm, and 40 mm. A peak load is generated when the movement (pressing amount) is 12.5 mm. If the movement exceeds this peak, the load decreases abruptly, and the dome shape is flattened and displaced towards the second shape. In this way, by adjusting the geometry of the second hydroxyl high-concentration region 14, various adjustments can be made to the action point reaching the paper-containing structure 50 and the triggering force for shape change.

[0148] then, Figure 20 Is Figure 18In the test pieces, the thickness of the tracing paper used as the paper sheet 2 was changed to 39.5 kg, 56.0 kg, and 88.0 kg based on the weight of a full sheet (1000 sheets). The narrowest width W of the two second high-hydroxyl concentration regions 14 was set to 10 mm, the length r1 to 24 mm, and the length r2 to 15 mm. Then, while gradually applying the load, the cross-sectional angle of the clamped first high-hydroxyl concentration region 11 before and after the morphological change was measured.

[0149] like Figure 20 As shown, a large angle change is obtained when the ream weight is 39.5kg and 56.0kg, but when the ream weight is 88.0kg, the paper sheet 2 is too thick and a moderate angle change cannot be obtained.

[0150] then, Figure 21 Is Figure 18 In the test piece, the results were measured on the cross-sectional angle of the clamping section of the first high-hydroxyl concentration region 11 when the printing width of the first high-hydroxyl concentration region 11 was changed to 6 mm, 8 mm, and 10 mm. The narrowest width W of the two second high-hydroxyl concentration regions 14 was set to 10 mm, the length r1 to 24 mm, and the length r2 to 15 mm. Then, the cross-sectional angle of the clamping section of the first high-hydroxyl concentration region 11 was measured while gradually applying a load.

[0151] like Figure 21 As shown, as the printing width of the first high-hydroxyl concentration region 11 increases to 6mm, 8mm, and 10mm, the angle change becomes larger. This proves that the tensile stress generated by the first high-hydroxyl concentration region 11 increases with the increase of the width of the first high-hydroxyl concentration region 11.

[0152] [Fourth Implementation Method]

[0153] Figure 22 and Figure 23 This describes a paper-containing structure 60 as a fourth embodiment of the present invention. In this paper-containing structure 60, a circular opening 61 is formed in the center of a square paper-containing sheet 2. On the first surface 1a of the paper-containing sheet 2, a strip-shaped first high-hydroxyl concentration region 11 is formed radially from the opening 61 along the diagonal of the paper-containing sheet 2 by printing with water or an aqueous solution. Furthermore, on the second surface 1b of the paper-containing sheet 2, a strip-shaped second high-hydroxyl concentration region 14 is formed radially from the opening 61 by printing with water or an aqueous solution, reaching the center of each side of the paper-containing sheet 2. Moreover, the paper-containing sheet 2, as a whole, is bent into a spherical shape and thoroughly dried while being stamped or otherwise required. The widths of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 become thicker towards the outer edge. Furthermore, the opening 61 is formed to appropriately bend the fold lines at the points where the fold lines converge on the paper-containing sheet 2.

[0154] After the drying process, the paper sheet 2 generates tensile stress that needs to be reduced in the width direction within the second high hydroxyl concentration region 14. Additionally, tensile stress that needs to be reduced in the width direction of the first high hydroxyl concentration region 11 is also generated within it. However, since the paper sheet 2 is stamped by bending it as a whole, the resistance to deformation relative to the force applied to bending the paper sheet 2 along the first and second high hydroxyl concentration regions 11 and 14 is high, and almost no deformation occurs due to the tensile stress in the first and second high hydroxyl concentration regions 11 and 14. Therefore, as... Figure 23 As shown, the paper sheet 2 is stable in a first shape that is bent as a whole.

[0155] Next, through the analysis of... Figure 23 A first, shape-stable paper-containing structure 60 is subjected to a pressing force on the central portion of the first surface 1a. The curved shape of the paper-containing sheet 2 approaches flatness, the deformation resistance of the paper-containing sheet 2 weakens, and the tensile stress caused by the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is greater. The paper-containing sheet 2 deforms by concave towards the first surface 1a along the first high-hydroxyl concentration region 11 and concave towards the first surface 1a along the second high-hydroxyl concentration region 14. Thus, maintaining... Figure 22 The second shape, which appears as a cross when viewed from above and a triangle when viewed from the front, is shown and then stops. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation occurs.

[0156] Therefore, according to the paper-containing structure 60, in Figure 23 In the first shape shown, which is a convex curved surface, by applying a pressing force to the central portion of the first surface 1a, it changes to... Figure 22 The second shape shown can achieve various functions in this process. For example, by taking the second shape into a mountain shape with the paper-containing structure 60, it can hold other items, perform switch operations, or raise other items by increasing the height of the dome of the paper-containing structure 60.

[0157] Alternatively, instead of bending the paper sheet 2, an annular protrusion 62 can be formed coaxially with the opening 61 at the center of the paper sheet 2. The cross-section of the annular protrusion 62 is convexly curved. Using the annular protrusion 62, the resistance to deformation relative to the force applied when bending the paper sheet 2 along the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is improved, and deformation caused by tensile stress in the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is almost eliminated. Thus, as... Figure 23As shown, the paper sheet 2, as a whole, is stable in a flat first shape. On the other hand, by pressing down on the center of the paper sheet 2, the annular protrusion 62 becomes nearly flat, the deformation resistance of the paper sheet 2 weakens, and the tensile stress caused by the first high-hydroxyl concentration region 11 and the tensile stress caused by the second high-hydroxyl concentration region 14 are greater. The paper sheet 2 deforms by being recessed towards the first surface 1a along the first high-hydroxyl concentration region 11 and towards the first surface 1a along the second high-hydroxyl concentration region 14. Thus, it maintains... Figure 22 The second shape, which appears as a cross when viewed from above and a triangle when viewed from the front, is shown and then stops. In this case, in the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced without causing further deformation.

[0158] [Fifth Implementation Method]

[0159] Figures 24-29 This refers to a gripper (including a paper structure) 70 for drones, as a fifth embodiment of the present invention. Furthermore, the gripper of the present invention is not limited to drones; it can be applied to any object as long as it is installed on a moving object and used to grip it. For example, it can be installed on the front end of a robot, a robotic arm, a small autonomous vehicle, an insect or other living organism, or a human body. Additionally, the gripping direction can be set according to the position of the object to be gripped; it can be the lower end, side end, or upper end of the paper sheet.

[0160] like Figure 28 as well as Figure 29 As shown, the drone gripper 70 is mounted on the support 75 at the lower end of the flying drone 74 and covers the target item 77, thereby automatically closing the drone gripper 70 to grip and lift the item 77. Furthermore, the mounting method of the drone gripper 70 is not limited to the downward position shown in the figure. For example, it can be mounted sideways to the side of the drone 74 to grip items located to the side, or mounted upwards to the upper end of the drone 74 to grip items located above the drone 74. Additionally, the drone gripper of the present invention can also change from a second shape to a first shape, gripping the item until the destination point, and releasing or placing the item from the drone at the destination point.

[0161] like Figure 24 and Figure 25 As shown, the paper sheet 2 of the gripper 70 of the drone has rectangular roll-up portions 71 formed on both sides of the two long sides of the rectangular main body, forming an overall H-shape. Gaps 72 are formed between the roll-up portions 71.

[0162] like Figure 24As shown, on the first surface 1a of the paper sheet 2, four high-hydroxyl concentration regions 11 are formed radially from the opening 73 toward each roll deformation section 71. Additionally, as... Figure 25 As shown, on the second surface 1b of the paper sheet 2, multiple high-concentration areas 14 of the second hydroxyl group are formed at the illustrated position by printing with water or an aqueous solution. Specifically, these are: a strip-shaped high-concentration area 14 extending from the opening 73 to each gap 72; a strip-shaped high-concentration area 14 extending from the opening 73 along both sides of the upper bend line 5 formed in the center of the paper sheet 2; a high-concentration area 14 of the second hydroxyl group formed on the entire surface of the roll-formed section 71; and a high-concentration area 14 of the second hydroxyl group close to the roll-formed section 71. Furthermore, as... Figure 28 As shown, the paper sheet 2 is bent and fully dried with the first surface 1a recessed. The roll deformation section 71 is wound into a cylindrical shape in the initial state by the tensile stress of the second hydroxyl high concentration region 14. This roll deformation section 71 is formed to sufficiently increase the strength of the contact area with the article 77 when holding the article 77.

[0163] The drone gripper 70 is fixed to the support 75 of the drone 74 through the opening 73, thus suspending the drone 74. In this state, the opening 73 is curved upwards, opening the roll-up portion 71. This state is the first shape.

[0164] Next, the drone was lowered to 74 degrees. Figure 28 The first shape-stabilized drone gripper 70 comes into contact with the object 77. Upon collision with the object 77, the central portion of the drone gripper 70 is lifted and protrudes upwards, as... Figure 29 The drone flips over as shown. Thus, the drone covers the item 77 with the grip 70, and the roll-up part 71 abuts against the lower end of the item 77 for support. Therefore, by raising the drone 74, the item 77 can be lifted.

[0165] That is, by applying the force that lifts the second surface 1b to the paper sheet 2, the paper sheet 2 flips downward, weakening its resistance to deformation. The tensile stress caused by the first high-hydroxyl concentration region 11 and the tensile stress caused by the second high-hydroxyl concentration region 14 are greater. The paper sheet 2 deforms by concave towards the first surface 1a along the first high-hydroxyl concentration region 11 and towards the second surface 1b along the second high-hydroxyl concentration region 14. Thus, as Figure 26 and Figure 27As shown, the shape remains narrower at the bottom, i.e., the second shape, and stops. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced without further deformation. While supporting the article 77, the deformation resistance caused by the article 77 is also applied, thus... Figure 26 Until the state remains narrow, item 77 is clamped and becomes compressed.

[0166] Therefore, according to the gripper 70 of the drone, in Figure 28 In the first shape shown, which curves upwards, the shape changes by applying an upward pushing force to the center of the second surface 1b. Figure 29 The downward-narrowing second shape shown enables the device to hold the item 77 during this process. Thus, by simply raising and lowering the drone 74, the drone automatically closes with the gripping member 70 to grasp the item 77, thereby avoiding complicating the construction of the drone 74 and enabling a low-cost automatic gripping device. If the coiled deformation section 71 is lifted from the state of holding the item 77, it then... Figure 28 The item is in a raised state, making it easy to release. As item 77, it can be used for various purposes, such as producing fruits and other crops, medicine, mail, and food processing in food chemical industries.

[0167] [Sixth Implementation Method]

[0168] Figures 30-32 This refers to a honeycomb structure-based cushioning material 80, as a sixth embodiment of the present invention. The honeycomb structure possesses advantageous structural characteristics of high porosity and lightweight. The air layer within the hexagonal cells of the honeycomb structure prevents convection and also provides excellent thermal cushioning performance, i.e., thermal insulation. Furthermore, in the event of an impact, energy is dispersed across adjacent surfaces, resulting in excellent impact absorption characteristics. The cushioning material of the present invention can be widely used as the core material of a sandwich structure sandwiched between panels on both sides. Small holes can also be opened on a single-sided flat plate of the sandwich structure to allow sound to resonate within the honeycomb, thereby achieving a sound-absorbing effect. Therefore, the cushioning material of the present invention can be used in various applications as a cushioning material with advanced functions. Furthermore, in the present invention, instead of a honeycomb structure for the cylindrical wall portion, a triangular cylindrical shape, a quadrilateral cylindrical shape, a pentagonal cylindrical shape, etc., can also be achieved. The cushioning material of the present invention can also be used as a support for temporary landing of drones, a support for deploying sensors at heights, and a container or support for the recovery of items and debris at disaster or accident sites.

[0169] Regarding the cushioning material with a honeycomb structure, the cushioning material 80 is in a second shape as its mode of use, such as Figure 32As shown, it has a three-dimensional shape having one or more openings 81, a cylindrical wall portion 82 erected around the openings 81, and a support portion 83 extending from the cylindrical wall portion 82. In its non-use state, as... Figure 30 and Figure 31 As shown, a first shape in the form of a flat plate is adopted. In the first shape of the flat plate, there is an advantage that multiple cushioning materials 80 can be stacked and stored. If expanded, articles can be stored into the opening 81 of the cylindrical wall portion 82, and become cushioning materials 80 that protect articles from forces from the vertical and horizontal directions of the cylindrical wall portion 82 and the support portion 83.

[0170] like Figure 30 and Figure 31 As shown, the paper sheet 2 of the cushioning material 80 is elongated rectangular in shape, and rectangular openings 81 are formed at intervals in the center of the width direction.

[0171] like Figure 30 As shown, on the first surface 1a of the paper sheet 2, nine high-concentration regions 11 of the first hydroxyl group are formed by printing with water or an aqueous solution, extending from each opening 81. Additionally, as... Figure 31 As shown, on the second surface 1b of the paper sheet 2, multiple regions 14 with high concentrations of second hydroxyl groups are formed at the position shown by printing with water or aqueous solution.

[0172] Specifically, such as Figure 30 As shown, the first high hydroxyl concentration region 11 is formed by: a thin first high hydroxyl concentration region 11 extending from the foot of the perpendicular line along the trisection of the long side of the opening 81 toward the long side of the paper sheet 2; a relatively thick first high hydroxyl concentration region 11 connecting the short sides of the opening 81; and a relatively thick first high hydroxyl concentration region 11 extending from the short side of the opening 81 toward the center of the short side of the paper sheet 2.

[0173] In addition, such as Figure 31 As shown, the second high-hydroxyl concentration region 14 includes: a thin second high-hydroxyl concentration region 14 extending from both ends of the long side of the opening 81 along the foot of the perpendicular line toward the long side of the paper sheet 2; a semi-circular thin second high-hydroxyl concentration region 14 arranged to surround both ends of the long side of the opening 81; and a semi-circular thin second high-hydroxyl concentration region 14 arranged to surround the center of each short side of the paper sheet 2.

[0174] After the cushioning material 80 forms a first high-hydroxyl concentration region 11 and a second high-hydroxyl concentration region 14 through printing or the like, it is pressed into a flat shape by means of a paper sheet 2 as needed, and the cushioning material 80 is stacked and stored. If it can remain flat after printing and drying, pressing is not required. In this state, because the cushioning material 80 is stacked, the tensile stress of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 antagonizes the deformation resistance of the paper sheet 2, thus maintaining the first flat shape.

[0175] If the cushioning material 80 is removed and a mechanical stimulus (triggering force) is applied to it, the deformation resistance of the paper sheet 2 weakens, and the tensile stress caused by the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 becomes greater. The paper sheet 2 deforms by indenting along the first high-hydroxyl concentration region 11 towards the first surface 1a and along the second high-hydroxyl concentration region 14 towards the first surface 1a. Thus, the cushioning material 80... Figure 32 The change shown stops at the second shape. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation occurs.

[0176] According to this cushioning material 80, in its flat first shape, it has the advantage of being able to stack and accommodate multiple cushioning materials 80. If a triggering force is applied and it deforms, it can accommodate an item into the opening 81 of the cylindrical wall portion 82, becoming a cushioning material 80 that protects the item from forces from the vertical and horizontal directions by the cylindrical wall portion 82 and the support portion 83. Therefore, a low-cost cushioning material 80 with sufficient cushioning force can be obtained. Since no plastic is used, it is also environmentally friendly.

[0177] [Seventh Implementation Method]

[0178] Figures 33-36 This refers to the cushioning material 90 according to the seventh embodiment of the present invention. The cushioning material 90 has a structure that makes the cushioning material 80 of the sixth embodiment continuous in the width direction. In a second shape as a usage of the cushioning material 90, such as... Figure 36 As shown, it has a three-dimensional shape with four openings 91, cylindrical wall portions 92 standing around the openings 91, and support portions 93 extending from the cylindrical wall portions 92. The cylindrical wall portions 92 are interconnected by the support portions 93. In the state where the cushioning material 90 is not used, as... Figure 33 and Figure 34As shown, a first shape in the form of a flat plate is adopted. In the first shape of the flat plate, there is an advantage that multiple cushioning materials 90 can be stacked and stored. If expanded, articles can be stored into the opening 91 of the cylindrical wall portion 92, and become cushioning materials 90 that protect articles from forces from the vertical and horizontal directions of the cylindrical wall portion 92 and the support portion 93.

[0179] like Figure 33 and Figure 34 As shown, the paper sheet 2 of the cushioning material 90 is rectangular in shape, and rectangular openings 91 are formed in three rows that are spaced apart from each other.

[0180] like Figure 33 As shown, on the first surface 1a of the paper sheet 2, a first high-hydroxyl concentration region 11 is formed by printing with water or an aqueous solution, extending from each opening 91. Additionally, as... Figure 34 As shown, on the second surface 1b of the paper sheet 2, multiple regions 14 with high concentrations of second hydroxyl groups are formed at the position shown by printing with water or aqueous solution.

[0181] Specifically, such as Figure 33 As shown, the first high hydroxyl concentration region 11 includes: a thin first high hydroxyl concentration region 11 extending from the trisection of the long side of the opening 91; a relatively thick first high hydroxyl concentration region 11 connecting the short sides of the opening 91; a relatively thick first high hydroxyl concentration region 11 extending from the short side of the opening 91 toward the center of the short side of the paper sheet 2; and a semi-circular first high hydroxyl concentration region 11 arranged to surround the short side of the opening 91 in the center.

[0182] In addition, such as Figure 34 As shown, the second high-hydroxyl concentration region 14 includes: a thin second high-hydroxyl concentration region 14 extending from both ends of the long side of the opening 91 toward the foot of the vertical line of the long side of the paper sheet 2; a semi-circular thin second high-hydroxyl concentration region 14 arranged to surround both ends of the long side of the opening 91 on both sides; and a semi-circular thin second high-hydroxyl concentration region 14 having a center on each short side of the paper sheet 2.

[0183] After the cushioning material 90 forms the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 through printing or the like, the paper sheet 2 is formed into a flat plate shape by stamping or the like as needed, and the cushioning material 90 is stacked and stored. If it can remain flat after printing and drying, stamping is not required. In this state, because the cushioning material 90 is stacked, the tensile stress of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 antagonizes the deformation resistance of the paper sheet 2, thus maintaining the first flat shape.

[0184] If the cushioning material 90 is removed and a mechanical stimulus (triggering force) is applied to it, the deformation resistance of the paper sheet 2 weakens, and the tensile stress caused by the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 becomes greater. The paper sheet 2 deforms by indenting along the first high-hydroxyl concentration region 11 towards the first surface 1a and along the second high-hydroxyl concentration region 14 towards the first surface 1a. Thus, the cushioning material 90... Figure 35 and Figure 36 The change shown stops at the second shape. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation occurs.

[0185] According to this cushioning material 90, in its flat first shape, it has the advantage of being able to stack and accommodate multiple cushioning materials 90. If a triggering force is applied and it deforms, it can accommodate items into the openings 91 of multiple cylindrical wall portions 92, becoming a cushioning material 90 that protects the items from forces from the vertical and horizontal directions by the cylindrical wall portions 92 and the support portions 93. Therefore, a low-cost cushioning material 90 with sufficient cushioning force can be obtained. Since plastic is not used, it is also environmentally friendly.

[0186] [Eighth Implementation Method]

[0187] Figures 37-39 This represents the cushioning material 100 according to the eighth embodiment of the present invention. In a second shape representing a usage of the cushioning material 100, such as… Figure 39 As shown, it has a three-dimensional shape with interlaced square openings 101 and undulations 102 connecting the openings 101. The undulations 102 have alternating upper and lower bends. In the state without the cushioning material 100, as... Figure 38 and Figure 39 As shown, a first shape in the form of a flat plate is adopted. In the first shape of the flat plate, there is an advantage that multiple cushioning materials 100 can be stacked and stored. If expanded, items can be stored in the valley part of the undulating part 102, which becomes a cushioning material 100 that protects the items from forces from the vertical and horizontal directions.

[0188] like Figure 37 As shown, on the first surface 1a of the paper sheet 2, a first high-hydroxyl concentration region 11 is formed by printing with water or an aqueous solution, etc., extending from each opening 101. Additionally, as... Figure 38 As shown, on the second surface 1b of the paper sheet 2, multiple high-concentration regions 14 of the second hydroxyl group are formed at the illustrated position by printing with water or an aqueous solution. The high-concentration regions 11 of the first hydroxyl group and the high-concentration regions 14 of the second hydroxyl group form a so-called Miura folding pattern.

[0189] After the cushioning material 100 forms a first high-hydroxyl concentration region 11 and a second high-hydroxyl concentration region 14 through printing or the like, it is pressed into a flat sheet shape by stamping, and the cushioning material 100 is stacked to store the cushioning material 100. In this state, because the cushioning materials 100 are stacked, the tensile stress of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 antagonizes the deformation resistance of the paper sheet 2, thus maintaining the first flat shape.

[0190] If the cushioning material 100 is removed and a mechanical stimulus (triggering force) is applied to it, the deformation resistance of the paper sheet 2 weakens, and the tensile stress caused by the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is greater. The paper sheet 2 deforms by indenting along the first high-hydroxyl concentration region 11 towards the first surface 1a and along the second high-hydroxyl concentration region 14 towards the first surface 1a. Thus, as Figure 39 As shown, the cushioning material 100 changes to a second shape with a Miura folded structure and then stops. In the second shape, the tensile stress generated by the first high-hydroxyl concentration region 11, the tensile stress of the second high-hydroxyl concentration region 14, and the deformation resistance of the paper sheet 2 are balanced, and no further deformation occurs.

[0191] According to this cushioning material 100, in its flat first shape, it has the advantage of being able to stack and accommodate multiple cushioning materials 100. If a triggering force is applied and it deforms, it can accommodate items into the valleys between the undulating portions 102, becoming a cushioning material 100 that protects items from forces from the vertical and horizontal directions via the cylindrical wall portion 102 and the support portion 103. Therefore, a low-cost cushioning material 100 with sufficient cushioning force can be obtained. Since plastic is not used, it is also environmentally friendly.

[0192] Figure 40 This illustrates an implementation that further extends the Miura folding structure. Other patterns include... Figure 41 As shown, it can also be in the shape of an egg carton.

[0193] [Ninth Implementation Method]

[0194] Figure 42 This is an enlarged cross-sectional view showing a ninth embodiment of the paper-containing structure 1 of the present invention. In this ninth embodiment, a protective film 104 is fixed to the first surface 1a and the second surface 1b of the paper-containing sheet 2, which has a first high-hydroxyl concentration region 11 and a second high-hydroxyl concentration region 14 formed in various patterns, via an adhesive layer 103 covering the entire surface. The paper-containing sheet 2 can be any type of paper-containing sheet 2 described in this application specification.

[0195] By using the protective film 104 to sandwich the paper sheet 2, even if the paper structure 1 is placed in a humid or high-humidity location, unwanted moisture will not penetrate into the paper sheet 2, thus maintaining the deformability of the paper sheet 2 based on the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14. Furthermore, when holding items with high moisture content, such as fruits, by the paper structure 1, it is also possible to prevent the paper structure 1 from absorbing moisture from the items. Therefore, the water content of fruits, etc., can be maintained. Moreover, by covering the surface with the protective film 104, the coefficient of friction of the surface in contact with fruits, etc., increases, thereby improving the stability of the items in their contained state.

[0196] As the protective film 104, various plastics with excellent moisture resistance are preferred, and the material is not limited. Examples include linear short-chain branched polyethylene (LLDPE), low-density polyethylene (LDPE), and other polyethylenes; unstretched polypropylene (CPP) and other polyolefin resins; polyvinyl acetate resins; polyvinyl chloride resins; poly(meth)acrylic acid resins; polyurethane resins, and other resins. The thickness of the protective film 104 is not limited, but in order to maintain adequate moisture resistance and not hinder the deformation of the paper sheet 2, it is preferably 0.001 μm or more and 10,000 μm or less, and more preferably 0.01 μm or more and 100 μm or less. Furthermore, from the viewpoint that the protective film 104 should not hinder the deformation of the paper sheet 2 as much as possible, the thickness of the paper sheet 2 can be 0.01 μm or more and 10,000 μm or less, more preferably 1 μm or more and 1,000 μm or less, and the thickness of the protective film 104 can be 0.001% or more and 1,000% or less of the thickness of the paper sheet 2, more preferably about 1% or more and 100% or less.

[0197] As the adhesive layer 103, for example, single-component or two-component cured or non-cured vinyl adhesive layers, (meth)acrylic adhesive layers, polyamide adhesive layers, polyester adhesive layers, polyether adhesive layers, polyurethane adhesive layers, epoxy adhesive layers, rubber adhesive layers, other solvent-based adhesive layers, water-based adhesive layers, emulsion adhesive layers, and other adhesives can be used. In the case of dry lamination, the adhesive diluted with an organic solvent is applied to the protective film 104, and after drying, it is pressed and bonded to a pair of protective films 104 through a paper sheet 2 with a first high-hydroxyl concentration region 11 and a second high-hydroxyl concentration region 14 pre-formed using heated rollers.

[0198] Alternatively, in the paper-containing structure 1, it can also be as follows: Figure 42As shown, the ends of the protective films 104 on both sides extend onto the end faces of the paper sheet 2 to form end face protective films 105, and the end faces of the paper sheet 2 are airtightly sealed by the plastic constituting the protective films 104. For a paper-containing structure 1 with protective films 104 attached to both sides of the paper sheet 2 via adhesive layers 103, if it is cut by irradiating a laser beam using a laser cutter or the like, the protective films 104 (and adhesive layers 103) melt at high temperature and flow along the end faces of the paper sheet 2, forming an end face protective film 105 that airtightly covers the end faces of the paper sheet 2. Therefore, it is easy to form... Figure 42 The end face is sealed. However, the paper-containing structure 1 of the ninth embodiment may also have a structure without the end face protective film 105.

[0199] [Tenth Implementation Method]

[0200] In the ninth embodiment, protective films 104 are provided on both sides of the paper sheet 2, but it can also be as follows: Figure 43 As shown, a protective film 104 is provided only on one side of the paper sheet 2 via the adhesive layer 103. In applications such as applying water droplets only to one side of the paper sheet 2, there is no problem even if the second side 1b of the paper sheet 2 is exposed.

[0201] Furthermore, in the ninth and tenth embodiments, instead of providing the protective film 104 on the entire surface of the paper sheet 2, the protective film 104 may be formed only in necessary areas via the adhesive layer 103 in a specific pattern. Necessary areas refer to areas that come into contact with moisture or other liquids, or areas that come into contact with items with high moisture content, such as fruits.

[0202] Alternatively, if the material of the protective film 104 is suitable, the adhesive layer 103 may not be provided, and the protective film 104 may be directly heated and softened and then pasted onto the paper sheet 2 for heat sealing.

[0203] [Eleventh Implementation Method]

[0204] Figure 44 This is an enlarged cross-sectional view showing the eleventh embodiment of the present invention. In this eleventh embodiment, a protective film 104 is adhered to both sides of the paper sheet 2, on which a first high-hydroxyl concentration region 11 and a second high-hydroxyl concentration region 14 are pre-formed, via an adhesive layer 103. Then, a nonwoven fabric 107 is further adhered to the entire surface of the protective film 104 on one side via an adhesive layer 106. By using a pair of protective films 104 to protect the paper sheet 2 from moisture, maintaining the deformability of the paper sheet 2, and by using the nonwoven fabric 107 to make the contact surface with the article soft, it is possible to protect the article and absorb excess moisture from the article. The nonwoven fabric 107 can be formed with a certain pattern according to the purpose.

[0205] [Twelfth Implementation Method]

[0206] Figure 45 This is an enlarged cross-sectional view showing the twelfth embodiment of the present invention. In this twelfth embodiment, there is a structure in which a protective film 104 is attached to both sides of a paper sheet 2 having a first high hydroxyl concentration region 11 and a second high hydroxyl concentration region 14 pre-formed, and then a circuit layer 108 is provided on one side of the protective film 104, and a protective film 109 is used to cover it.

[0207] The circuit layer 108 can have a circuit made of a metal thin film with high conductivity such as copper or aluminum and arranged in a certain pattern, as well as sensors, resistors, capacitors, integrated circuits, coils, antennas, etc. set on the circuit, which, combined with the deformability of the paper sheet 2, can play the necessary functions of sensing, signal processing, communication, etc.

[0208] [Thirteenth Implementation Method]

[0209] Figure 46 This is a top view showing the sensing pad 110 according to the twelfth embodiment of the present invention. The sensing pad 110 has a three-dimensional shape suitable for a specific part of a living organism such as a human or animal and a plurality of sensors 111, which perform the following functions: detecting electrical signals, temperature, conductivity, concentration of specific substances, etc. of the living organism through the sensors 111, processing the signals, and transmitting them to the outside through the cable 112. A protective film 104 may be formed on both sides of the paper sheet 2 via an adhesive layer 103, or it may be a type without a protective film 104.

[0210] The shape of the sensing pad 110 is not limited; the illustrated example is cross-shaped. A first high-hydroxyl concentration region 11, which appears V-shaped when viewed from above, is formed towards the center of the front end of four extensions extending from the center. A second high-hydroxyl concentration region 14 is formed transversely across the first high-hydroxyl concentration region 11 at the root of the extensions. Through the action of these first high-hydroxyl concentration regions 11 and second high-hydroxyl concentration regions 14, the sensing pad 110 can deform into a gently concave surface on its back when subjected to a triggering force, for example, allowing it to be mounted approximately without gaps to the human head 113. Multiple sensors 111 are disposed on the back of the sensing pad 110 and connected to a central cable 112 via electronic circuitry (not shown). When the sensing pad 110 is placed along the curved surface of the head 113, all sensors 111 come into contact with the surface of the head 113, detect electrical signals, and transmit them through the cable 112. Thus, electrical signals at multiple points on the head 113 can be detected, for example, for brain diagnosis and analysis.

[0211] [Thirteenth Implementation Method]

[0212] Figure 48 and Figure 49These are partial cross-sectional views of a plan view and a cross-sectional view showing an absorbent pad 120 used as a sanitary napkin or the like, as described in the thirteenth embodiment of the present invention. Figure 48 As shown, the absorbent pad 120 is, for example, a rectangular shape with rounded corners, such as... Figure 49 As shown, the device has a support 122 containing a paper sheet 2 and an absorbent layer 121 covering both sides of the support 122. Their outer peripheries are pressed together to form a sealing portion 123. In the paper sheet 2, in areas other than the sealing portion 123, as shown... Figure 37 The grid-like pattern shown has a first high-hydroxyl concentration region 11, a second high-hydroxyl concentration region 14, and an opening 101, which are referred to as Figure 37 Explanation.

[0213] The absorbent pads 120 are stacked and housed within a housing (not shown). When removed from the housing, the release of compression becomes a triggering force, causing the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 to bend, as shown. Figure 49 As shown, the cross-sectional shape becomes serrated. As a result, the pair of absorbent layers 121 expand and swell, thereby not only increasing the absorbable capacity of menstrual blood and other liquids and preventing leakage, but also reducing discomfort such as the absorbent layers 121 being too close to the skin due to the unevenness of the support 122.

[0214] [Fourteenth Implementation]

[0215] Figure 50 This is a top view showing the conical structure 124 according to the fourteenth embodiment of the present invention. The conical structure 124 has a square-shaped paper sheet 2 with a circular central hole 125 formed in the center. First hydroxyl high-concentration regions 11 are formed radially from the central hole 125 at equal intervals at fixed angles on the upper surface of the paper sheet 2. Furthermore, a weakening line 126 extending radially from the outer periphery to the central hole 125 is formed on a portion of the paper sheet 2, allowing it to be easily torn by hand along the weakening line 126. In this fourteenth embodiment, a second hydroxyl high-concentration region 14 is not required.

[0216] According to the conical structure 124, if the weakening line 126 is cut, it becomes the triggering force. Through the stress generated by the first high hydroxyl concentration region 11, the conical structure 124 is deformed into a conical shape with the central hole 125 as the apex. Figure 51 and Figure 52 Indicates actual production Figure 50 The photograph of the conical structure 124 shown is shown. Figure 51 This indicates that before cutting the weakening line 126, Figure 52 This indicates the state where the weakening line 126 is cut and deformed into a cone shape. For example... Figure 42 or Figure 43 As shown, the paper sheet 2 preferably has a protective film 104 adhered to at least its upper surface via an adhesive layer 103. The conical structure 124 can also be used as tableware or a container, as long as the pointed end faces down and food, containers, etc. are placed in the recess. Alternatively, the pointed end can be used to cover an item as a protective cover.

[0217] In addition, Figure 51 and Figure 52 In the example shown, a square tracing paper with a thickness of 153 μm and a length and width of 200 mm is used as the paper sheet 2. A circular hole with a diameter of 10 mm is formed as the central hole 125. A pattern of a first high-hydroxyl concentration region 11 with a width of 0.95 mm and a length of 70 mm is formed radially around the central hole 125 at 6° angles using pure water. About 2 minutes after printing, an adhesive layer 103 made of polyethylene with a thickness of 10 μm, which is sprayed with "3M Spray 55" (3M's trade name), is adhered to both sides of the paper sheet 2 to form a conical structure 124. It can be confirmed that the conical structure 124 is indeed deformed into a conical shape.

[0218] [Fifteenth Implementation]

[0219] Figure 53 This is a top view showing the catalyst unit 127 according to the fifteenth embodiment of the present invention. The catalyst unit 127 has a cylindrical catalyst container 128, a paper-containing sheet 2 disposed within the catalyst container 128, and catalyst layers 131 fixed to both sides of the paper-containing sheet 2. The two ends of the catalyst container 128 taper to become an inlet portion 129 and an outlet portion 130 connected to the outside.

[0220] The paper sheet 2 is a relatively long rectangle, as shown in... Figure 37 The grid-like pattern shown has a first high-hydroxyl concentration region 11, a second high-hydroxyl concentration region 14, and an opening 101, which are referred to as Figure 37 The following describes the process: A long paper sheet 2, with catalyst layers 131 fixed on both sides, is rolled into a spiral to form a cylinder, which is then sealed inside a catalyst container 128. Gaps are formed between the layers of the paper sheet 2, and the cross-sectional shape of the paper sheet 2 is serrated. Therefore, the fluid flows in a tortuous manner within the gaps, which improves the contact efficiency with the catalyst layer 131.

[0221] [Sixteenth Implementation]

[0222] Figure 54 and Figure 55This is a photograph, taken as the sixteenth embodiment of the present invention, showing a cushioning material 100 for arranging small fruits or foods such as strawberries or cherries in a box before and after deformation. The paper sheet 2 of the cushioning material 100 does not have an adhesive layer 103 or a protective film 104 formed. A first high-hydroxyl concentration region 11 is formed on the surface of the paper sheet 2, and a [missing information - likely a specific texture or structure] is formed on the back side. Figure 37 The second high-hydroxyl concentration region 14 is shown in a grid pattern, with rectangular openings 101 formed at the intersections of the grid. The paper sheet 2 is 420 mm long × 297 mm wide and 123 μm thick, and is formed from tracing paper. The distance between the centers of the openings 101 of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is 51 mm. The width of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14 is 15 mm, and they are formed by printing pure water using an inkjet printer. Figure 54 This is a photo of the printed state. Figure 55 This is a photograph taken from the state where the cushioning material is compressed by 100 from all sides (a state where a triggering force has been applied).

[0223] [Seventeenth Implementation]

[0224] Figure 56 and Figure 57 This is a photograph of a cushioning material 133 with a protective film, which is formed as the seventeenth embodiment of the present invention. A protective film 104 is adhered to both sides of a paper sheet 2 formed in the same manner as in the sixteenth embodiment, and then an opening 101 is formed. The shape of the cushioning material 133 with the protective film, the printed patterns of the first high-hydroxyl concentration region 11 and the second high-hydroxyl concentration region 14, and the size and arrangement of the opening 101 are the same as those of the cushioning material 100, except that the adhesive layer 103 and the protective film 104 are formed on both sides of the paper sheet 2. Furthermore, no opening 101 is formed in the adhesive layer 103 or the protective film 104. It is manufactured as follows. After printing pure water onto the paper sheet 2 using an inkjet printer, approximately 10 minutes later, a protective film 104 of polyethylene with a thickness of about 10 μm is applied to both sides of the paper sheet 2 using an adhesive layer 103 formed by spraying a commercially available spray adhesive (3M product name: 3M Spray Adhesive 55). The blank portion is cut off using a laser cutter, and the end face of the protective film 104 is melted to form an end face protective film 105, sealing the cross-section of the paper sheet 2. Further heating at 90°C for 5 minutes with an electric heater causes the protective film 104 to deform based on thermoplasticity, mimicking the paper sheet 2. The film is then manually adjusted and bent to obtain a cushioning material 133 with a protective film.

[0225] Figure 56 This is a photo showing the state after applying the protective film (104). Figure 57This is a photograph taken from the perspective of the protective buffer material 133 being compressed (under a triggered force). Figure 55 and Figure 57 The comparison shows that in the buffer material 133 with a protective film, where the protective film 104 is fixed to both sides by the adhesive layer 103, the same deformation occurs as in the buffer material 100 without the protective film 104.

[0226] Figure 58 It is Figure 57 A photograph of strawberries being placed in a strawberry packaging box (117mm x 210mm x 50mm) is taken of the protective film cushioning material 133 compressed and placed in the central recess (bag). This protective film cushioning material 133, with its complex three-dimensional shape, can be easily manufactured using inkjet printing. Furthermore, a moisture-proof protective film 104 is formed on the cushioning material 133, thus allowing for long-term preservation of the strawberries' flavor.

[0227] [Moisture Absorption Experiment]

[0228] A portion of the cushioning material 100 of the sixteenth embodiment without a protective film 104 formed on the paper sheet 2 and a portion of the cushioning material 133 of the seventeenth embodiment with a protective film 104 formed on it were used as samples, and the difference in hygroscopicity of the samples was investigated. The surface area (one side) of the cut samples was a total of 150 cm². 2 The internal volume is 430 cm². 3 Two airtight containers were placed in an environment with constant temperature and humidity, with the lids open. The temperature was set to room temperature. The constant humidity environment was conditioned using a saturated salt method with high-humidity NaCl, achieving a relative humidity of approximately 75%. After the temperature and humidity stabilized, each sample and a humidity sensor were sealed together in the airtight container, and the humidity readings from the humidity sensor were measured over time. The results are shown below. Figure 60 .

[0229] like Figure 60 As shown, in the sample of the sixteenth embodiment without the protective film 104, the relative humidity decreased to about 60% after about 1000 seconds. In contrast, in the sample of the seventeenth embodiment with the protective film 104, the relative humidity was about 73% after about 1000 seconds, remaining approximately constant. It can be seen that the protective film 104 can prevent the paper sheet 2 from absorbing moisture.

[0230] The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. The structural elements of the above embodiments can be combined with each other, or other known structures can be combined.

[0231] For example, in addition to the embodiments described above, from the viewpoint of maintaining an appropriate distance from the object through deformation of the paper sheet 2, this invention can also be applied to skin care products (cosmetics), electrostatic adhesive pads, wristbands, tourniquets, etc. From the viewpoint of increasing surface area, it can be applied to filters, in addition to catalyst units. From the viewpoint of imparting a curved shape, it can be applied to filters, speakers, ultrasonic components, displays, hats, helmets, shoe insoles, etc. From the viewpoint of compactness through deformation, it can be applied to space shelters, furniture, tableware, parachutes, etc. From the viewpoint of changes in optical properties brought about by deformation, it can be applied to the construction of windows and walls that prevent peeping. From the viewpoint of cushioning function, it can be applied to helmets, protectors for drone equipment, propellers, etc. From the viewpoint of changes in heat insulation and heat resistance caused by deformation, it can be applied to beverage sleeves, etc. Based on the pop-out effect caused by deformation, it can be applied to picture books. From the viewpoint of folding, it can be applied to stickers, labels, office equipment, etc.

[0232] Industrial availability

[0233] According to the present invention, by applying a triggering force to a portion of a paper-containing structure having a first high-hydroxyl concentration region and a second high-hydroxyl concentration region, the antagonistic balance between tensile stress and resistance to deformation within the paper-containing structure changes, switching between a first shape and a second shape in at least one direction. This switching action enables various functions, thus facilitating industrial applications.

[0234] Explanation of reference numerals in the attached figures

[0235] 1. Paper-containing structure

[0236] 1a First page

[0237] 1b Second page

[0238] 2. Paper sheet

[0239] 5. Upward bend line

[0240] 6. Downward bend line

[0241] 9 Water

[0242] 11 High concentration region of the first hydroxyl group

[0243] 14. High concentration region of the second hydroxyl group

[0244] 20, 30, 40, 50, 60, 70, 80, 90, 100 (including paper structures)

[0245] 22 Weakening Line

[0246] 61 Opening

[0247] 62. Annular protrusion

[0248] 70 UAV gripper

[0249] Volume 71, Modified Section

[0250] 73 Opening

[0251] 74 drones

[0252] 75 Support components

[0253] 77 items

[0254] 80 Cushioning Material

[0255] 81 Opening

[0256] 82. Cylinder wall section

[0257] 83 Support section

[0258] 90 Cushioning material

[0259] 91 Opening

[0260] 92. Cylinder wall section

[0261] 93 Support section

[0262] 100 Cushioning Material

[0263] 101 Opening

[0264] 102. Undulating section

[0265] 103 Adhesive Layer

[0266] 104 Protective Film

[0267] 105 End Face Protective Film

[0268] 106 Adhesive Layer

[0269] 107 Nonwoven Fabric

[0270] 108 circuit layers

[0271] 109 Protective Film

[0272] 110 Sensing Pad

[0273] 111 Sensor

[0274] 112 cable

[0275] 113 Head

[0276] 120 Absorbent Pad

[0277] 121 Absorption Layer

[0278] 122 Support body

[0279] 123 Sealing section

[0280] 124 Conical structure

[0281] 125 center hole

[0282] 126 Weakening Line

[0283] 127 Catalyst Unit

[0284] 128 Catalyst Container

[0285] 129 Import Department

[0286] 130 Export Department

[0287] 131 Catalyst Layer

[0288] 132 access

[0289] 133 Cushioning material with protective film

Claims

1. A paper-containing structure, characterized in that, formed of a paper-containing sheet in a dry state including paper, the paper-containing sheet has a first face and a second face which mutually form surface back faces, a first hydroxyl high concentration region in which the density of hydroxyl groups is higher than other parts of the first face is formed on the first face, a second hydroxyl high concentration region in which the density of hydroxyl groups is higher than other parts of the second face is formed on the second face, tensile stress is respectively generated in the first hydroxyl high concentration region and the second hydroxyl high concentration region, the tensile stress of the first hydroxyl high concentration region of the first face and the tensile stress of the second hydroxyl high concentration region of the second face are balanced with the deformation resistance of the paper-containing sheet when the paper-containing structure is in a first shape to form a first stable state, and are able to maintain the first shape, and also are balanced with the deformation resistance of the paper-containing sheet when the paper-containing structure is in a second shape to form a second stable state, and are able to maintain the second shape, the first shape and the second shape are switched to at least one direction by applying a trigger force to a part of the paper-containing structure.

2. The paper-containing structure according to claim 1, wherein In the first and second high-hydroxyl concentration regions, the transmittance of infrared light is lower than in the other regions when the infrared absorption spectrum of the surface portion of the paper-containing structure is measured by total reflection measurement using infrared light of a wave number of 3331 cm -1 -1.

3. The paper-containing structure according to claim 1 or 2, wherein one or more notched portions through which the first stable state and the second stable state can be formed are formed on the paper-containing sheet.

4. The paper-containing structure according to claim 1 or 2, wherein the trigger force is generated by penetration of water into the paper-containing structure, change in humidity of an environment in which the paper-containing structure is placed, local compression of the paper-containing structure, heating of the paper-containing structure, cooling of the paper-containing structure, cutting of a part of the paper-containing structure, or application of an external force to the paper-containing structure.

5. The paper-containing structure according to claim 1 or 2, wherein the first shape and the second shape are bidirectionally switched by applying the trigger force to a part of the paper-containing structure.

6. A holding member characterized by comprising: a paper-containing structure according to claim 1 or 2 is used for holding an article, the first shape is an article release shape in which end portions are opened, the second shape is an article holding shape in which the end portions are narrowed, the trigger force is generated by collision of the holding member with an article or contact of the holding member with a support surface on which an article is supported, whereby the paper-containing structure changes from the article release shape to the article holding shape to hold the article.

7. A holding member for a drone, characterized by a holding member according to claim 6 has a fixing portion in a central portion of the holding member which is fixed to a support portion of a drone.

8. A cushioning material characterized by, a paper-containing structure according to claim 1 or 2 is used for arranging one or more articles therein, the paper-containing structure has a paper folding structure, the first shape is a reduced shape in which the paper-containing structure is folded without having a bag or a flat shape in which the paper-containing structure is unfolded, the second shape is an unfolded shape in which the paper-containing structure is unfolded to form one or more bags, the change from the reduced shape or the flat shape to the unfolded shape is made by applying a trigger force to a part of the paper-containing structure.

9. A paper folding device, characterized by a paper-containing structure according to claim 1 or 2 and at least one of an electronic element and a wiring provided to at least one of the first face and the second face of the paper-containing structure.

10. A cushioning material characterized by, The paper-containing structure according to claim 1 or 2, for arranging one or a plurality of articles therein, The paper-containing structure has a paper-folding structure, The first shape is a reduced shape in which the paper-containing structure is folded without having a bag, or a flat shape in which the paper-containing structure is unfolded, The second shape is an unfolded shape in which the paper-containing structure is unfolded to have one or a plurality of bags, The change from the reduced shape or the flat shape to the unfolded shape is made by applying a trigger force to a portion of the paper-containing structure.

11. A cushioning material characterized by, The paper-containing structure according to claim 1 or 2, The paper-containing structure has one or a plurality of opening portions and the first and second high-hydroxyl regions arranged around the opening portions, The first shape is a flat shape in which the paper-containing structure is unfolded, The second shape is a three-dimensional shape in which the paper-containing structure has a cylindrical wall portion that stands around a periphery of the opening portion and a support portion that extends from the cylindrical wall portion, The change from the flat shape to the three-dimensional shape is made by applying a trigger force to a portion of the paper-containing structure.

12. A method for manufacturing a paper-containing structure, which manufactures the paper-containing structure according to claim 1 or 2, characterized by, The process has the following steps: A liquid containing water is applied to portions of the first and second faces of the paper-containing sheet that are to form the first and second high-hydroxyl regions; and The liquid is dried.

13. The paper-containing structure according to claim 1 or 2, wherein A protective film having flexibility is attached to at least a portion of at least one of the first and second faces of the paper-containing sheet.

14. The paper-containing structure according to claim 1 or 2, wherein Protective films having flexibility are attached to the first and second faces of the paper-containing sheet, respectively.

Images