Packaging material and method for producing packaging material

Abstract

The main purpose is to provide a technique capable of manipulating the occurrence of "migration" from a foam material to an object in contact therewith. The present technology provides a paper foam material comprising a fibrous material comprising waste paper and / or pulp, a binder, sodium bicarbonate, a surfactant, a water-soluble softener, and a carboxylic acid anhydride having a saturated and / or unsaturated hydrocarbon group. The paper foam material according to the present technology can be used for one or more uses selected from the group consisting of cushioning material uses, packaging material uses, sound absorbing material uses, thermal insulation material uses and refractory material uses.

Description

Technical Field

[0001] The present technology relates to a packaging material and a method for manufacturing the packaging material. Background Art

[0002] Conventionally, many cushioning materials used for transporting office automation (OA) equipment, home appliances, etc. include synthetic resin materials. Examples thereof include synthetic resin products such as styrene foam, high-foam polyethylene sheet, polyethylene foam, and bubble wrap.

[0003] On the other hand, there is a global demand for cushioning materials made from environmentally friendly, recyclable materials. Examples of recyclable cushioning materials include those made from paper. However, cushioning materials made from paper have a problem in that their physical properties, such as durability, elasticity, and resilience, are inferior to those made from synthetic resins.

[0004] In recent years, technologies have been developed to improve the physical properties of cushioning materials using recyclable paper as a raw material. For example, Patent Document 1 discloses a lightweight and elastic cushioning material comprising a molded foam obtained by mixing a paper component with a binder containing 50% by weight or more of gelatin or alginic acid.

[0005] In addition, Patent Document 2 discloses a molded foam in which the generation of crater-like dents is reduced and elastic properties are excellent, the molded foam being obtained by kneading a fiber material with an aqueous solution in which a binder is dissolved and foaming and molding the mixture, wherein the binder is mainly composed of gelatin and / or animal glue having a gel strength of 130 Bloom or more.

[0006] Citation List

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. H10-152173

[0009] Patent Document 2: Japanese Patent Application Laid-Open No. 2002-293980 Summary of the Invention

[0010] Problems to be solved by the present invention

[0011] As described above, as a technology for improving the physical properties of cushioning materials made from recyclable paper and the like, foam materials with excellent elasticity have been developed. However, there is a real need for further improvement. For example, when conventional foam materials made from paper are stored in contact with, for example, resin, metal, or the like, there is a problem of so-called "migration," in which chemicals seep from the foam and discolor the contacting object (such as the resin, metal, etc.) due to the chemical seepage. When foam materials that cause migration are used as cushioning materials for packaging products, traces of the cushioning material remain in the areas where the product and the cushioning material are in close contact, resulting in defective products with foreign matter attached.

[0012] Furthermore, in the case of forming a packaging material having a hybrid configuration by combining a foam material causing migration with another cushioning material, there is a problem in that the cushioning characteristics of the cushioning material are deteriorated due to the migration of components of the foam material to the other cushioning material.

[0013] Accordingly, a primary object of the present technology is to provide a technique that can manipulate the "migration" that occurs from a foam material to an object in contact therewith.

[0014] Solution to the problem

[0015] That is, first, the present technology provides a paper foam material comprising a fiber material including waste paper and / or pulp,

[0016] Binder,

[0017] Sodium bicarbonate,

[0018] surfactants,

[0019] Water-soluble softeners, and

[0020] Carboxylic acid anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group.

[0021] In the paper foam material according to the present technology, the molar ratio of the carboxylic anhydride to the softener may be 0.01 to 2.

[0022] In the paper foam material according to the present technology, the saturated hydrocarbon group and / or the unsaturated hydrocarbon group may have a carbon atom number of 12 to 24.

[0023] In the paper foam material according to the present technology, the carboxylic anhydride may include an alkenyl carboxylic anhydride. In this case, as the alkenyl carboxylic anhydride, octadecenyl carboxylic anhydride may be used. Also, in this case, as the octadecenyl carboxylic anhydride, octadecenyl succinic anhydride may be used.

[0024] In paper foam materials according to the present technology, polyols may be used as softeners.

[0025] The paper foam material according to the present technology can include an anti-staining agent. In this case, the anti-staining agent can include alum.

[0026] The paper foam material according to the present technology can include an antimicrobial agent. In this case, the antimicrobial agent can include potassium sorbate.

[0027] In the paper foam material according to the present technology, the binder may include polyvinyl alcohol.

[0028] In the paper foam material according to the present technology, the surfactant may include a polyoxyethylene alkyl ether.

[0029] The paper foam material according to the present technology may have a sheet shape subjected to one or more processes selected from embossing, dimple processing, protrusion processing, and hollow processing.

[0030] Paper foam materials according to the present technology may be bonded to a substrate using an adhesive layer interposed between the paper foam material and the substrate.

[0031] The paper foam material according to the present technology can be used for one or more applications selected from the group consisting of cushioning material applications, packaging material applications, sound absorbing material applications, heat insulating material applications, and fire-resistant material applications.

[0032] Next, the present technology provides a method for manufacturing a paper foam material, the method comprising: a mixing step of mixing a composition, the composition comprising:

[0033] Fibrous material comprising waste paper and / or pulp,

[0034] Binder,

[0035] Sodium bicarbonate, and

[0036] surfactants, and contains

[0037] Water-soluble softeners, and

[0038] Carboxylic anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group; and

[0039] A foaming step of foaming the composition.

[0040] The manufacturing method according to the present technology may further perform a molding step of molding the composition by using a mold and / or an embossed sheet.

[0041] The production method according to the present technology may further include performing a drying step of drying the foamed composition.

[0042] The manufacturing method according to the present technology may further include a lamination step of laminating the dried composition on the foamed composition. In this case, the manufacturing method may further include a wetting step of wetting the dried composition with a liquid before the lamination step. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a drawing replacing a photograph showing an example of the sound absorbing material 100 or the heat insulating material 200 according to the present technology.

[0044] Figure 2 is shown with Figure 1 Drawings of different examples of sound absorbing materials 100 or heat insulating materials 200 according to the present technology are provided instead of photographs.

[0045] Figure 3 FIG. 1 is a flow chart of a first embodiment of a method for manufacturing a paper foam material 1 used in the present technology.

[0046] Figure 4 1 is a flow chart of a second embodiment of a method for manufacturing the paper foam material 1 used in the present technology.

[0047] Figure 5 It is a drawing instead of a photograph showing an example of the form of the foam material 1 used in the present technology.

[0048] Figure 6 yes Figure 5 A cross-sectional view of the foam material 1 is shown in FIG.

[0049] Figure 7 is a schematic diagram illustrating an example of the form of the foam material 1 used in the present technology.

[0050] Figure 8 It is a diagram with Figure 7 Schematic diagram of examples of different forms of foam materials 1 used in the present technology.

[0051] Figure 9 is shown with Figure 7 and Figure 8 Instead of photographs, drawings show examples of different forms of foam materials 1 used in the present technology.

[0052] Figure 10 is shown with Figures 7 to 9 Instead of photographs, drawings show examples of different forms of foam material 1 used in the present technology.

[0053] Figure 11 is shown with Figures 7 to 10 Instead of photographs, drawings show examples of different forms of foam material 1 used in the present technology.

[0054] Figure 121 is a schematic diagram illustrating an example of the first embodiment or the second embodiment of the method for producing the foam material 1 used in the present technology.

[0055] Figure 13 It is an icon Figure 12 Schematic diagram of examples of different methods for producing foam materials 1 used in the present technology.

[0056] Figure 14 It is a diagram with Figure 12 and Figure 13 Schematic diagram of examples of different methods for producing foam materials 1 used in the present technology.

[0057] Figure 15 It is a diagram with Figure 12 、 Figure 13 and Figure 14 Schematic diagram of examples of different methods for producing foam materials 1 used in the present technology.

[0058] Figure 16 1 is a flow chart of a third embodiment of a method for manufacturing the paper foam material 1 used in the present technology.

[0059] Figure 17 : is a schematic diagram illustrating an example of a third embodiment of the method for producing the foam material 1 used in the present technology.

[0060] Figure 18 It is a diagram with Figure 17 Schematic diagram of examples of different methods for producing foam materials 1 used in the present technology.

[0061] Figure 19 1 is a flow chart of a fourth embodiment of a method for producing the foam material 1 used in the present technology.

[0062] Figure 20 is a drawing in lieu of a photograph illustrating an example of a composite material 2 used in the present technology.

[0063] Figure 21 is shown with Figure 20 Instead of photographs, drawings show examples of different composite materials 2 used in the present technology.

[0064] Figure 22 1 is a flow chart of a first embodiment of a method for manufacturing a composite material 2 used in the present technology.

[0065] Figure 23 is a schematic diagram illustrating an example of a method for manufacturing the composite material 2 according to the present technology.

[0066] Figure 24 It is a diagram with Figure 23 Schematic diagrams of examples of different methods for manufacturing composite materials 2 according to the present technology.

[0067] Figure 25 It is a diagram with Figure 23 and Figure 24 Schematic diagrams of examples of different methods for manufacturing composite materials 2 according to the present technology.

[0068] Figure 26 is a schematic diagram illustrating a first embodiment of a multilayer structure 3 used in the present technology.

[0069] Figure 27 is a schematic diagram illustrating a second embodiment of the multilayer structure 3 used in the present technology.

[0070] Figure 28 is a schematic diagram illustrating a third embodiment of the multilayer structure 3 used in the present technology.

[0071] Figure 29 is a schematic diagram illustrating a fourth embodiment of the multilayer structure 3 used in the present technology.

[0072] Figure 30 is a schematic diagram illustrating a fifth embodiment of the multilayer structure 3 used in the present technology.

[0073] Figure 31 is a schematic diagram illustrating a sixth embodiment of the multilayer structure 3 used in the present technology.

[0074] Figure 32 is a flow chart of a first embodiment of a method for manufacturing a multilayer structure 3 used in the present technology.

[0075] Figure 33 is a graph showing the results of the sound absorption test of Experimental Example 4.

[0076] Figure 34 This is a photograph substituted for the accompanying drawing of the fragrance material / deodorant material manufactured in Experimental Example 7.

[0077] Figure 35 is a drawing-substitute photograph showing the results of coloring treatment performed on the paper foam material according to the present technology in Experimental Example 8.

[0078] Figure 36 is a photographic substitute for the accompanying drawing of the composite material produced in Experimental Example 9.

[0079] Figure 37 It is a drawing-substitute photograph showing the steps of recycling the paper foam material according to the present technology in Experimental Example 10.

[0080] Figure 38 It is a drawing-substitute photograph showing the result of performing soil reduction on the paper foam material according to the present technology in Experimental Example 11.

[0081] Figure 39 It is a drawing showing the results of growing plants in Experimental Example 11 in place of photographs.

[0082] Figure 40 It is a drawing-substitute photograph showing the results of growing plants by hydroponic cultivation in Experimental Example 11.

[0083] Figure 41 It is a drawing-substitute photograph showing the results of growing plants by mushroom bed cultivation in Experimental Example 11. DETAILED DESCRIPTION

[0084] Hereinafter, preferred embodiments for carrying out the present technology will be described with reference to the accompanying drawings.

[0085] The embodiments to be described below are intended to illustrate representative embodiments of the present technology. Therefore, the scope of the present technology should not be understood to be narrower due to these embodiments. Note that the description will be given in the following order.

[0086] 1.Paper foam material 1

[0087] (1) Fiber materials

[0088] (2) Adhesive

[0089] (3) Foaming accelerator

[0090] (4) Surfactants

[0091] (5) Water-soluble softener

[0092] (6) Carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group (7) Anti-discoloration agent

[0093] (8) Antimicrobial agents

[0094] (9) Other ingredients

[0095] (10) Specific gravity

[0096] (11) Application of paper foam material 1

[0097] 2. Method for manufacturing paper foam material 1

[0098] [First embodiment, second embodiment]

[0099] (1) Fiber separation step S1

[0100] (2) Binder mixing step S2

[0101] (3) Mixing step S3

[0102] (4) Foaming step S4

[0103] (5) Molding step S5

[0104] (6) Drying step S6

[0105] [Third embodiment]

[0106] (7) Humidification step S7

[0107] (8) Lamination Step S8 (First Lamination Step)

[0108] [Fourth embodiment]

[0109] (9) Coating step S9

[0110] (10) Lamination Step S10 (Second Lamination Step)

[0111] (11) Drying step S113. Composite material 2

[0112] (1) Base material 21

[0113] (2) Application of composite material 2

[0114] 4. Manufacturing method of composite material 2

[0115] (1) Attachment step S12

[0116] (2) Drying step S135. Multilayer structure 3

[0117] (1) Adhesive layer 32

[0118] (2) Form of multilayer structure 3

[0119] (3) Application of multilayer structure 3

[0120] 6. Method for manufacturing laminated structure 3

[0121] (1) Adhesive coating step S14

[0122] (2) Lamination Step S15 (Third Lamination Step)

[0123] (3) Drying step S16

[0124] (4) Molding step S171. Paper foam material 1

[0125] The paper foam material 1 used in this technology contains a fiber material, a binder, a foaming promoter, a surfactant, a water-soluble softener, and a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group. Furthermore, if necessary, the paper foam material 1 may contain other ingredients such as a discoloration preventer and an antibacterial agent. Each ingredient is described in detail below.

[0126] (1) Fiber materials

[0127] As the fiber material for the paper foam material 1 used in this technology, one, two, or more types of fiber materials that can be used for paper foam materials can be freely selected and used, as long as the effects of this technology are not impaired. Examples of fiber materials include waste paper (such as newspapers, magazines, books, and corrugated cardboard), paper pulp (such as bamboo, bagasse, and straw), etc. Among these materials, waste paper (such as newspapers, magazines, books, and corrugated cardboard) is preferably used in this technology from the perspective of recyclability. In addition, this material can also be used in combination with other fiber materials (for example, cotton fabric, wool fabric, glass fiber, chemical fiber, etc.).

[0128] More specifically, fibrous materials containing waste paper and / or pulp are preferably used for the paper foam material 1 used in the present technology. By using fibrous materials containing waste paper and / or pulp, recyclability can be improved. Waste paper can include, for example, newspapers, magazines, books, corrugated cardboard, etc. as described above. Pulp can include wood, non-wood, etc. Examples of non-wood include bamboo, bagasse, straw, etc.

[0129] The length of the fiber material used in the present technology can be freely set as long as the effect of the present technology is not impaired, but for example, a fiber material with fibers separated to a length of 0.3 to 1.2 mm, preferably 0.3 to 1.0 mm, more preferably 0.5 to 1.0 mm can be used.

[0130] (2) Adhesive

[0131] As a binder for the paper foam material 1 used in the present technology, one or two or more types of binders that can be used for paper foam materials can be freely selected and used as long as the effect of the present technology is not impaired. Examples of binders include polyvinyl alcohol, polyethylene glycol, polyethylene succinate, polybutylene succinate, dimerized adipate, polycaprolactone, polylactic acid, gum arabic, polysaccharides (e.g., carboxymethyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose, methyl cellulose, cellulose acetate, starch, carrageenan, xanthan gum, agar, guar gum, tara gum, locust bean gum, glucomannan, gum arabic, gellan gum, alginic acid, pectin, etc.), proteins (e.g., casein, gelatin, animal glue, egg white, etc.), etc. Among these binders, from the perspective of high environmental contribution, it is preferable to select one or two or more types of binders from polysaccharides and proteins.

[0132] The viscosity of the binder aqueous solution used for the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present technology are not impaired. However, for example, it is preferable to use a binder aqueous solution having a static viscosity of 50 mPa / s or greater at room temperature (25°C), and it is more preferable to use a binder aqueous solution having a static viscosity of 220 mPa / s or greater at room temperature. By using a binder aqueous solution having a static viscosity within the lower limit of the above range, the foaming properties of the material in the mixing step S3 in the method for producing the paper foam material 1 described later can be improved.

[0133] Furthermore, for example, it is preferable to use an aqueous binder solution having a static viscosity of 450 mPa / s or less at room temperature, and it is more preferable to use an aqueous binder solution having a static viscosity of 240 mPa / s or less at room temperature. By using an aqueous binder solution having a static viscosity at the upper limit of the above range, the processability of the material in the foaming step S4 in the method for producing the paper foam material 1 described later can be improved.

[0134] Note that, in the present technology, the static viscosity is a value measured by using a vibration viscometer VM-100A (manufactured by SEKONIC CORPORATION).

[0135] The structure of the binder used in the paper foam material 1 of the present technology is not particularly limited, as long as it does not impair the effectiveness of the present technology. However, it is preferred that the ratio of low-polarity functional groups relative to the total number of functional groups be small. By using a binder with a low ratio of low-polarity functional groups, the foaming properties of the material in the foaming step S4 of the method for producing the paper foam material 1, described later, can be improved. Specifically, a binder with a ratio of high-polarity functional groups of 6.7% to 23.3% is preferably used.

[0136] More specifically, for example, when polysaccharide carboxymethyl cellulose is used as a binder, the carboxymethyl cellulose has a hydroxyl group (-OH) and a carboxymethyl group (-CH2COO-), and the relationship between the polarities of these functional groups is hydroxyl group (-OH) < carboxymethyl group (-CH2COO-). Therefore, in the present technology, when carboxymethyl cellulose is used as a binder, it is preferred to use a carboxymethyl cellulose having a small ratio of carboxymethyl groups (-CH2COO-) (i.e., a low degree of etherification (degree of substitution (DS) value)). As a specific value, in the present technology, when carboxymethyl cellulose is used as a binder, it is preferred to use a carboxymethyl cellulose having a degree of etherification (DS value) between 0.2 and 0.7.

[0137] Furthermore, for example, in the case of using hydroxypropyl cellulose or hydroxyethyl cellulose, which are polysaccharides, as a binder, hydroxyl group (-OH), hydroxypropyl group (-CH2C(OH)HCH3) and hydroxyethyl group (-CH2CH2OH) are present in hydroxypropyl cellulose or hydroxyethyl cellulose, and the relationship between the polarities of these functional groups is hydroxyl group (-OH)>hydroxypropyl group (-CH2C(OH)HCH3), and hydroxyl group (-OH)>hydroxyethyl group (-CH2CH2OH). Therefore, in the present technology, in the case of using hydroxypropyl cellulose or hydroxyethyl cellulose as a binder, it is preferred to use hydroxypropyl cellulose or hydroxyethyl cellulose having a small ratio of hydroxyl group (-OH). As a specific value, in the present technology, in the case of using hydroxypropyl cellulose or hydroxyethyl cellulose as a binder, it is preferred to use hydroxypropyl cellulose or hydroxyethyl cellulose having a ratio of hydroxyl group (-OH) of 6.7 to 23.3%.

[0138] The content of the binder in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present invention are not impaired, but it is preferably 3 to 100 parts by mass, and more preferably 7 to 70 parts by mass, relative to 100 parts by mass of the fiber material.

[0139] The concentration of the binder aqueous solution used in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present technology are not impaired. However, for example, it is preferable to use a binder aqueous solution of 1% by mass or greater, and more preferably 2% by mass or greater. By using a binder aqueous solution having a lower limit value within this range, the strength of the paper foam material 1 to be produced can be improved.

[0140] Furthermore, for example, it is preferable to use an aqueous binder solution having a concentration of 11% by mass or less, more preferably 7% by mass or less, and still more preferably 5% by mass or less. By using an aqueous binder solution having an upper limit value within the above-mentioned concentration range, the foaming property of the material in the foaming step S4 in the method for producing the paper foam material 1 described later can be improved, and furthermore, the specific gravity of the paper foam material 1 to be produced can be reduced.

[0141] (3) Foaming accelerator

[0142] As the foaming agent for the paper foam material 1 used in the present technology, one or two or more types of foaming agents that can be used for paper foam materials can be freely selected and used as long as the effects of the present technology are not impaired. Examples of the foaming agent include azo compounds (such as azodicarbonamide (ADCA)), nitroso compounds (such as N,N'-dinitrosopentamethylenetetramine (DPT)), hydrazine derivatives (such as 4,4-oxybis(benzenesulfonylhydrazide) (OBSH) and hydrazinedicarbonamide (HDCA)), azo compounds (such as barium azodicarboxylate (Ba / AC)), bicarbonates (such as sodium bicarbonate), and the like. Among these substances, sodium bicarbonate is preferably used from the perspective of availability and economic efficiency.

[0143] In the present technology, by using sodium bicarbonate as a foaming accelerator, the specific gravity of a paper foam material using a fiber material containing waste paper and / or pulp can be reduced, and thus, cushioning characteristics and the like can be improved.

[0144] The content of the foaming promoter in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present invention are not impaired, but it is preferable to contain 0.5 to 15 parts by mass of the foaming promoter relative to 100 parts by mass of the fiber material, and more preferably 1 to 10 parts by mass of the foaming promoter.

[0145] (4) Surfactants

[0146] As a surfactant for the paper foam material 1 used in the present technology, one or two or more types of surfactants that can be used for paper foam materials can be freely selected and used as long as the effects of the present technology are not impaired. Examples of surfactants include polyoxyethylene alkyl ethers, sodium alkyl sulfates, alkyltrimethylammonium chlorides, alkyldiaminoethylglycine chlorides, and the like. Among these, polyoxyethylene alkyl ethers are preferably used from the perspective of accelerating foaming.

[0147] The content of the surfactant in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present invention are not impaired, but it is preferable that 0.1 to 50 parts by mass of the surfactant is contained, and more preferably 10 to 30 parts by mass of the surfactant is contained, relative to 100 parts by mass of the fiber material.

[0148] The concentration of the surfactant aqueous solution used in the paper foam material 1 used in the present invention is not particularly limited as long as the effects of the present invention are not impaired. However, for example, in the binder mixing step in the method for producing the paper foam material 1 described later, the surfactant aqueous solution is prepared so that the concentration of the surfactant in the mixture of the binder and the surfactant aqueous solution is preferably 1% by mass or greater, more preferably 3% by mass or greater, and even more preferably 4% by mass or greater. By preparing the surfactant so that the lower limit value of the concentration falls within the above range, the foaming properties of the material in the foaming step S4 in the method for producing the paper foam material 1 described later can be improved, and furthermore, the specific gravity of the paper foam material 1 to be produced can be reduced.

[0149] Furthermore, for example, in the binder mixing step in the method for producing the paper foam material 1 described later, the surfactant aqueous solution is prepared so that the concentration of the surfactant in the mixture of the binder and the surfactant aqueous solution is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. By preparing the surfactant so that the upper limit of the concentration falls within the above range, the foamability of the material in the mixing step S3 in the method for producing the paper foam material 1 described later can be improved.

[0150] (5) Water-soluble softener

[0151] A water-soluble softener is used in the paper foam material 1 used in the present technology. As the water-soluble softener used in the paper foam material 1 according to the present technology, one or two or more types of water-soluble softeners that can be used for paper foam materials can be freely selected and used, as long as the effects of the present invention are not impaired. Examples of water-soluble softeners include: urea and urea derivatives; polyols such as glycerin, ethylene glycol, diethylene glycol, polyethylene glycol, polyvinyl alcohol, propylene glycol, and butylene glycol; sugars such as sucrose and trehalose; sugar alcohols such as sorbitol; amines such as triethanolamine; and the like.

[0152] Incidentally, a softening agent that imparts elasticity is essential for paper foam materials made from fibrous materials containing waste paper and / or pulp, and glycerin has been commonly used as such a softening agent. However, when paper foam materials using glycerin are used for long periods of time as cushioning materials containing components such as resins and metals, a phenomenon called "migration" (discoloration of the components) may occur. While technologies have been developed to mitigate this "migration" phenomenon from paper foam materials, the softening agent significantly affects the cushioning capacity of the paper foam material, making it difficult to apply these conventional technologies to paper foam materials made from fibrous materials containing waste paper and / or pulp. Against this backdrop, the inventors of the present application have successfully reduced the occurrence of "migration" from the paper foam material 1 to the object it contacts, even when using any softening agent, by using a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, as described later.

[0153] Furthermore, the present technology has discovered that the occurrence of "migration" from the manufactured paper foam material 1 to the object it contacts can be controlled depending on the type of water-soluble softener. Specifically, by using a specific softener, even in a paper foam material using a fiber material containing waste paper and / or pulp, the "migration" phenomenon can be successfully suppressed while maintaining good cushioning properties.

[0154] When the goal is to reduce "migration," it is preferable to use a softening agent with a structure that has weak hydrogen bonding strength. Using a softening agent with a structure that has weak hydrogen bonding strength can prevent "migration" caused by hydrogen bonding. For example, because the relationship between hydrogen bonding strengths is OH > NH, using a softening agent with an imino group (NH group) can reduce the occurrence of "migration" from the manufactured paper foam material 1 to the object it contacts, compared to a softening agent with a hydroxyl group (OH group).

[0155] Furthermore, in the case of chemical substances having hydroxyl (OH) functional groups, the lower the ratio of the number of hydroxyl (OH) functional groups to the number of carbon atoms, the lower the hydrogen bonding strength, and the occurrence of "migration" from the manufactured paper foam material 1 to the object it contacts can be further reduced. Therefore, when using a polyol, it is preferable to use a polyol in which the relationship between the number of carbon atoms in the molecular structure and the number of hydroxyl (OH) functional groups is the number of hydroxyl functional groups < the number of carbon atoms.

[0156] In view of the above, in order to reduce the occurrence of "migration" from the paper foam material 1 to the object it contacts, among the above-mentioned softening agents, it is preferred to use: urea and urea derivatives; among the polyols having 3 to 15 carbon atoms, propylene glycol and 1,3-butylene glycol; and sucrose and trehalose.

[0157] In the case of using urea or urea derivatives, it is more preferred to use the chemical formula R 1 、R 2 -N-CO-NR 3 、R 4 (R 1 to R 4 :H or a saturated and / or unsaturated hydrocarbon group having 1 to 4 carbon atoms). This is because urea derivatives having 4 or less carbon atoms in the saturated and / or unsaturated hydrocarbon group are reliably water-soluble.

[0158] The content of the water-soluble softening agent in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present invention are not impaired, but it is preferable that 0.03 to 150 parts by mass of the water-soluble softening agent is contained relative to 100 parts by mass of the fiber material, and more preferably 0.05 to 100 parts by mass of the water-soluble softening agent is contained.

[0159] (6) Carboxylic anhydrides having saturated hydrocarbon groups and / or unsaturated hydrocarbon groups

[0160] The paper foam material 1 according to the present technology uses a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group. By using a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, the occurrence of "migration" from the paper foam material 1 to the object it contacts can be reduced even when using any softening agent.

[0161] For example, even in the case of using a polyol, in which "migration" is relatively likely to occur among the above-mentioned water-soluble softening agents, by using a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, the occurrence of "migration" from the paper foam material 1 to the object in contact can be reduced as shown in the examples described later. As a mechanism, it can be inferred that the oxygen derived from the carbonyl group of the carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group reacts with the hydroxyl group present in the water-soluble softening agent such as the polyol to suppress the "migration".

[0162] Examples of the saturated hydrocarbon group and / or unsaturated hydrocarbon group of the carboxylic anhydride used in the present technology include an alkyl group, an alkenyl group, and an alkynyl group, and it is preferred to use an alkenyl group.

[0163] The number of carbon atoms of the saturated hydrocarbon group and / or unsaturated hydrocarbon group of the carboxylic anhydride used in the present technology is not particularly limited, as long as the function and effect of the present technology are not damaged. From the perspective of enhancing stability, the number of carbon atoms is preferably 12 to 24. Specifically, the example of the saturated hydrocarbon group and / or unsaturated hydrocarbon group includes dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, eicosenyl, hexadecenyl, docosenyl, tricosenyl and tetracosenyl, and it is preferred to use octadecenyl.

[0164] The carboxylic anhydride used in the present technology is not particularly limited as long as the functions and effects of the present technology are not impaired. Examples of the carboxylic anhydride include acetic anhydride, propionic anhydride, oxalic anhydride, succinic anhydride, maleic anhydride, phthalic anhydride, and benzoic anhydride, and succinic anhydride is preferably used.

[0165] The content of the carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group in the paper foam material 1 according to the present technology is not particularly limited as long as the functional effects of the present technology are not impaired, but it is preferred to use the carboxylic anhydride in a molar ratio range of 0.01 to 2, more preferably in a molar ratio range of 0.06 to 1, and even more preferably in a molar ratio range of 0.2 to 0.7 relative to the softener.

[0166] (7) Anti-discoloration agent

[0167] The paper foam material 1 used in this technology may contain a discoloration preventive. As the discoloration preventive for the paper foam material 1 used in this technology, one, two, or more types of discoloration preventives commonly used in paper foam materials may be freely selected and used, as long as the effectiveness of this technology is not impaired. Examples of discoloration preventives include alum, magnesium, iron, copper, and the like. Among these, alum is preferably used from the perspectives of availability, disposal, and economic efficiency.

[0168] The content of the anti-discoloration agent in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present technology are not impaired, but it is preferable to contain 0.5 to 5 parts by mass of the anti-discoloration agent and more preferably 1 to 3 parts by mass of the anti-discoloration agent relative to 100 parts by mass of the fiber material.

[0169] (8) Antimicrobial agents

[0170] An antimicrobial agent may be used in the paper foam material 1 used in this technology. As the antimicrobial agent used in the paper foam material 1 used in this technology, one or two or more antimicrobial agents that are commonly used in paper foam materials may be freely selected and used, as long as the effectiveness of this technology is not impaired. Examples of antimicrobial agents include potassium sorbate, isopropylmethylphenol, salicylic acid, and the like. Among these, potassium sorbate is preferably used from the perspective of handling, such as water solubility.

[0171] The content of the antibacterial agent in the paper foam material 1 used in the present technology is not particularly limited as long as the effects of the present technology are not impaired, but it is preferable that 0.1 to 1.5 parts by mass of the antibacterial agent is contained and more preferably 0.15 to 1 part by mass of the antibacterial agent is contained relative to 100 parts by mass of the fiber material.

[0172] (9) Other ingredients

[0173] As the paper foam material 1 used in the present technology, one or more types of other additives that can be used for paper foam materials can be freely selected and used as needed. Examples of additives include cross-linking accelerators, mold release agents, pH adjusters, pH buffers, antifungal agents, colorants, bleaching agents, antioxidants, weathering (light resistance) agents, flame retardants, fillers, etc.

[0174] (10) Specific gravity

[0175] The specific gravity of the paper foam material 1 used in this technology can be freely adjusted depending on the application and purpose. The specific gravity of the paper foam material 1 used in this technology is, for example, 0.3 to 0.5, preferably 0.3 to 0.4. Furthermore, in the method for manufacturing the paper foam material 1 described later, the specific gravity of the foam mixture after the material mixing step S3 is, for example, 0.3 to 0.5, preferably 0.3 to 0.4. Furthermore, in the method for manufacturing the paper foam material 1 described later, the specific gravity of the mixture of the binder and the aqueous surfactant solution after the binder mixing step S2 is, for example, 0.2 to 0.7, preferably 0.2 to 0.35. By setting the specific gravity of the paper foam material 1, the foam mixture in the manufacturing step, and the mixture of the binder and the aqueous surfactant solution within the above-mentioned ranges, impact resistance, recovery after impact, and the like can be further improved.

[0176] Note that, in the present technology, the specific gravity is a value measured in accordance with JIS Z8804.

[0177] (11) Application of paper foam material 1

[0178] The use of the paper foam material 1 used in the present technology described above is not particularly limited, and the paper foam material 1 can be appropriately used for, for example, cushioning materials, packaging materials, sound absorbing materials, sound insulating materials, soundproofing materials, shockproofing materials, heat insulating materials, fire-resistant materials, wallpapers, aromatic materials, deodorizing materials, seat pads for automobiles, etc., maintenance materials, agricultural materials, etc.

[0179] Furthermore, if a recyclable material is used as the above-mentioned fiber material, its use as a recycled material can also be expected. Hereinafter, specific examples will be described.

[0180] [Sound-absorbing material 100]

[0181] As existing sound-absorbing materials, petroleum-derived foaming materials, glass wool, etc. are mainly used, but by using the paper foam material 1 according to the present technology as the sound-absorbing material 100, the deplasticization rate can be improved in various scenes requiring sound absorption such as wall interiors, accessories, walls, ceilings and various products.

[0182] Specifically, the present technology provides a sound absorbing material 100 comprising

[0183] Fibrous material comprising waste paper and / or pulp,

[0184] Binder,

[0185] Sodium bicarbonate, and

[0186] surfactants, and contains

[0187] Water-soluble softeners, and

[0188] Carboxylic acid anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group.

[0189] The sound absorbing material 100 according to the present technology may include a porous material. Examples of porous materials include carbonized materials such as activated carbon, microporous materials such as zeolite, mesoporous materials such as mesoporous silica (MCM, FSM, etc.), and macroporous materials such as pumice and coffee grounds.

[0190] In addition, if Figure 1 As shown in , the sound absorbing material 100 according to the present technology may have a structure in which a paper honeycomb structure is sealed in a paper foam material 1. In addition, as Figure 2 As shown in , the sound absorbing material 100 according to the present technology may have a structure in which a paper foam material 1 and a plate-like corrugated cardboard 102 are laminated.

[0191] Note that details of the fiber material, binder, foaming promoter, surfactant, water-soluble softener, carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, anti-discoloration agent, antibacterial agent, and other components that can be used in the sound absorbing material 100 according to the present technology are the same as those of the above-mentioned paper foam material 1, and therefore description thereof is omitted herein.

[0192] [Thermal insulation material 200]

[0193] As existing thermal insulation materials, petroleum-derived foaming materials, glass wool, etc. are mainly used, but by using the paper foam material 1 according to the present technology as the thermal insulation material 200, the deplasticization rate can be improved in various occasions requiring thermal insulation such as the interior of walls, accessories, walls, ceilings and various types of products.

[0194] Specifically, the present technology provides a thermal insulation material 200 comprising the following items:

[0195] Fibrous material comprising waste paper and / or pulp,

[0196] Binder,

[0197] Sodium bicarbonate, and

[0198] surfactants, and contains

[0199] Water-soluble softeners, and

[0200] Carboxylic acid anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group.

[0201] The heat insulating material 200 according to the present technology can adjust the heat insulating effect by changing the density of the paper foam material 1 by adjusting the foaming rate of the paper foam material 1 to be used, without increasing its thickness.

[0202] In addition, if Figure 1 As shown in , the heat insulating material 200 according to the present technology may have a structure in which a paper honeycomb structure is sealed in a paper foam material 1. In addition, as Figure 2 As shown in , the sound absorbing material 100 according to the present technology may have a structure in which a paper foam material 1 and a plate-like corrugated cardboard 102 are laminated.

[0203] It is noted that the details of the fiber material, binder, foaming promoter, surfactant, water-soluble softener, carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, anti-discoloration agent, antibacterial agent and other components that can be used in the thermal insulation material 200 according to the present technology are the same as those of the above-mentioned paper foam material 1, so their description is omitted herein.

[0204] [Refractory 300]

[0205] The paper foam material 1 according to the present invention can be used as a fire-resistant material 300 in cases where various regulations require it to have a flame retardant effect in various occasions (such as indoors). When using the paper foam material 1 according to the present invention as the fire-resistant material 300, a fire-resistant agent having a fire-resistant effect is preferably used for the paper foam material 1 of the present invention.

[0206] Specifically, the present technology provides a refractory material 300 comprising the following:

[0207] Fibrous material comprising waste paper and / or pulp,

[0208] Binder,

[0209] Sodium bicarbonate, and

[0210] surfactants, and

[0211] Water-soluble softener,

[0212] a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and

[0213] Fire retardant.

[0214] Examples of the refractory agent that can be used for the refractory material 300 according to the present technology include aluminum hydroxide, magnesium silicate, aluminum oxide, ceramics, silicon dioxide, boron, boric acid, and the like, and it is preferable to use aluminum hydroxide.

[0215] The content of the refractory agent in the refractory material 300 according to the present technology is not particularly limited as long as the effects of the present invention are not impaired, but depending on the type of the refractory agent and the refractory effect, the content of the refractory agent is preferably, for example, 2 to 500 parts by mass, more preferably 50 to 300 parts by mass, and even more preferably 80 to 250 parts by mass relative to 100 parts by mass of the fiber material.

[0216] Note that the details of the fiber material, binder, foaming promoter, surfactant, water-soluble softener, carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, anti-discoloration agent, antibacterial agent and other components that can be used in the refractory material 300 according to the present technology are the same as those of the above-mentioned paper foam material 1, and therefore their description is omitted herein.

[0217] [Fragrance material / deodorant material 400]

[0218] The paper foam material 1 according to the present invention can be used as a fragrance / deodorizing material 400. After being subjected to fragrance / deodorizing treatment, it can provide various aroma-based functions such as coloring, blending, and signature. When using the paper foam material 1 according to the present invention as a fragrance / deodorizing material 400, a fragrance and / or deodorizing agent having a fragrance / deodorizing effect is preferably used for the paper foam material 1 according to the present invention.

[0219] Specifically, the present technology provides a fragrance material and / or deodorizing material 400 comprising the following:

[0220] Fibrous material comprising waste paper and / or pulp,

[0221] Binder,

[0222] Sodium bicarbonate, and

[0223] surfactants, and contains

[0224] Water-soluble softener,

[0225] a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and

[0226] Fragrance and / or deodorant.

[0227] Examples of fragrances and / or deodorants that can be used for the fragrance / deodorizing material 400 according to the present technology include compost materials, carbonized materials (such as tri-carbon or activated carbon), coffee grounds, tea grounds, dried flowers, etc.

[0228] It is noted that the details of the fiber material, binder, foaming promoter, surfactant, water-soluble softener, carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, anti-discoloration agent, antibacterial agent and other components that can be used in the fragrance material / deodorizing material 400 according to the present technology are the same as those of the above-mentioned paper foam material 1, and therefore their description is omitted herein.

[0229] 2. Method for manufacturing paper foam material 1

[0230] Because the paper foam material 1 according to the present technology has a novel composition, its production method is not particularly limited. However, as a suitable method, the paper foam material 1 can be produced using the production method according to the present technology described below. The production method of the paper foam material 1 used in the present technology can include at least a mixing step S3 and a foaming step S4. Furthermore, if necessary, a fiber separation step S1, a binder mixing step S2, a molding step S5, a drying step S6, a coating step S9, a humidification step S8, a lamination step S10, and a drying step S11 can also be performed. Each step will be described in detail below in chronological order.

[0231] [First embodiment, second embodiment]

[0232] Figure 3 FIG. 1 is a flow chart of a first embodiment of a method for manufacturing a paper foam material 1 used in the present technology. Figure 4 1 is a flow chart of a second embodiment of a method for manufacturing the paper foam material 1 used in the present technology.

[0233] (1) Fiber separation step S1

[0234] The fiber separation treatment step S1 is a step of fiber separation of the fiber material to be the raw material of the paper foam material 1 used in the present technology. Note that, in the case of using an already fiber-separated fiber material, the fiber separation treatment step S1 is not necessarily required.

[0235] In the present technology, as a fiber separation treatment method, one or a combination of two or more general fiber separation treatment methods may be used, as long as the effectiveness of the present technology is not impaired. For example, either a wet fiber separation method or a dry fiber separation method may be used. Specific fiber separation methods such as cutting, pounding, crushing, impact crushing, and ultrasonic crushing can be freely combined and used depending on the type of raw material.

[0236] (2) Binder mixing step S2

[0237] The binder mixing step S2 is a step of mixing the binder with an aqueous solution containing a surfactant (see Figure 4 (The second embodiment shown in FIG. 2 ) Even if all materials are mixed in the mixing step S3 described later, without performing the binder mixing step S2, the paper foam material 1 used in the present technology can be produced. However, when a binder containing one or more selected from polysaccharides and proteins is used as the binder, it is preferable to perform the binder mixing step S2. By performing the binder mixing step S2, the binder and surfactant in the aqueous solution can be efficiently and fully mixed.

[0238] (3) Mixing step S3

[0239] The mixing step S3 is a step of mixing various types of components used for the paper foam material 1 according to the present technology. Specifically, the mixing step is a step of mixing a fiber material, a binder, a foaming promoter, a surfactant, a water-soluble softener, and a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and other components such as a discoloration preventing agent and an antibacterial agent as needed.

[0240] Note that the mixing step S3 can be performed simultaneously with the foaming step S4 described later. That is, foaming can be performed simultaneously with the mixing of various types of components.

[0241] (4) Foaming step S4

[0242] The foaming step S4 is a step of foaming a mixture of various components used in the paper foam material 1 according to the present technology. Specifically, the foaming step is a step of foaming a mixture containing a fiber material, a binder, a foaming promoter, a surfactant, a water-soluble softener, and a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and other components such as an anti-discoloration agent and an antibacterial agent as needed.

[0243] The foaming method in the foaming step S4 may be performed by one or a combination of two or more general foaming methods, as long as the effect of the present technology is not impaired. Examples of the foaming method include a method of foaming the mixture while stirring and mixing the mixture, a method of foaming the mixture by forcibly passing a gas into the mixture, a method of foaming the mixture by adding a foaming agent to the mixture, and the like.

[0244] Specifically, for example, in the mixing step S3, a composition containing various types of components for the paper foam material 1 used in the present technology may be mixed at a first rotation speed. Specifically, in the mixing step S3, a composition containing a fiber material, a binder, sodium bicarbonate, a surfactant, a water-soluble softener, and a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and other components such as an anti-discoloration agent and an antibacterial agent as needed may be mixed at a first rotation speed.

[0245] Note that the mixing step S3 also includes a case where foaming occurs simultaneously with mixing of the composition containing various types of ingredients. That is, in the mixing step S3, foaming may be started while the composition is being mixed at a first rotational speed, and in the foaming step S4, foaming may be further performed while the composition is being mixed at a second rotational speed.

[0246] In the foaming step S4, a composition containing various components used in the present technology may be foamed at a second rotation speed higher than the first rotation speed. More specifically, the foaming step S4 is a step of foaming the composition containing a fiber material, a binder, sodium bicarbonate, a surfactant, a water-soluble softener, and a carboxylic anhydride having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group, and other components such as a discoloration preventing agent and an antimicrobial agent as needed, at a second rotation speed higher than the first rotation speed.

[0247] In order to reduce the specific gravity of paper foam materials using fibrous materials containing waste paper and / or pulp to improve their cushioning properties, etc., when mixing the materials to be used for the paper foam materials, various materials have been added separately, and designs have been devised to change the rotation speed for mixing and gradually mix the materials, etc., which has complicated the manufacturing process. On the other hand, the inventors of the present application have successfully produced a paper foam material with excellent cushioning properties and a low specific gravity by using sodium bicarbonate as a foaming promoter and mixing each material at once without changing the rotation speed.

[0248] (5) Molding step S5

[0249] The molding step S5 is a step of molding the composition into a desired shape. The molding method in the molding step S5 can be performed by one or a combination of two or more general molding methods, as long as the effect of the present technology is not impaired. Examples of molding methods include injection molding, extrusion molding, compression molding, blow molding, calendaring molding, cast molding, etc.

[0250] The specific shape to be formed in the forming step S5 is not particularly limited and can be freely designed according to the purpose of the paper foam material 1 to be manufactured, etc. Figure 5 As shown in , paper foam material can be formed into sheets and embossed. For example, Figure 6 As shown in FIG, by performing embossing, even if the indentations are locally generated (see Figure 6 B), the dent will also be restored by the restoring force (see Figure 6 C), so the paper foam material can be suitably used as a cushioning material or a packaging material.

[0251] Furthermore, for example, paper foam materials can be formed as Figure 7 Alternative forms of bubble cushioning materials such as those shown in Figure 8 The simple flakes shown in Figure 9 The forms shown in A to C have wavy protrusions on one or both surfaces.

[0252] The paper foam material 1 for the packaging material according to the present technology may include a sheet-like base layer 11 having a first surface 111 and a second surface 112. The thickness L1 of the base layer 11 (see Figure 7 ) can be freely designed according to the use and purpose of the paper foam material 1. The thickness L1 of the base layer 11 (see Figure 7 ) may be, for example, 1 mm or more, preferably 2 mm or more, and may be 3 mm in consideration of cushioning properties and formability. By increasing the thickness L1 of the base layer 11 (see Figure 7 ) is set within this range, the strength of the paper foam material 1 can be further improved.

[0253] A plurality of structures 12 may be formed on the first surface 111 and / or the second surface 112 of the base layer 11. The shape of the structures 12 is not particularly limited and may be formed as Figure 7 and Figure 9 The shape shown in the figure and the shape described below Figure 10 and Figure 11 Although not shown in the figure, a shape can be formed by combining structures 12 of different shapes, or a plurality of structures 12 of different shapes can be formed separately. Moreover, a plurality of structures 12 can be formed at intervals.

[0254] The thickness of the structure 12 can be freely designed according to the use and purpose of the paper foam material 1. The thickness L2 of the structure 12 (see Figure 7 ) can be set to 2 to 10 mm, for example; for example, in the following Figure 10 In the case of the shape in the figure, the thickness L2 may preferably be set to 8 to 10 mm; and for example, in the following Figure 11 In the case of the shape in FIG, the thickness L2 can be preferably set to 2 to 6 mm. Figure 7 ) is set within this range, the strength of the paper foam material 1 can be further improved.

[0255] In the paper foam material 1 for packaging materials according to the present technology, the thickness L2 of the structure 12 (see Figure 7 ) is preferably formed thicker than the thickness L1 of the base layer 11 (see Figure 7 ) thick. By setting the thickness L2 of the structure (see Figure 7 ) is formed to be thicker than the thickness L1 of the base layer 11 (see Figure 7 ) is thick, which can further improve the impact resistance, recovery after impact, etc.

[0256] By adjusting the thickness L1 of the base layer 11 (see Figure 7 ) and the thickness L2 of the structure 12 (see Figure 7 ) and the thickness L3 of the paper foam material 1 obtained by adding Figure 9 B) can be Figure 9 The constant thickness is shown in B, or it can be Figure 9 A and C show a structure having a thick portion L31 and a thin portion L32.

[0257] In the paper foam material 1 used for the packaging material according to the present technology, the surface roughness of one or more surfaces selected from the first surface 111 and the second surface 112 of the base layer 11 and the surface of the structure 12 can also be freely designed according to the use and purpose of the paper foam material 1.

[0258] In forming step S5, mould and / or embossing sheet can be used.As the material of the mould and / or embossing sheet used in the present technology, mould and / or embossing sheet of various materials can be used, as long as the effect of the present technology is not damaged.As the material of the mould and / or embossing sheet that can be used in the present technology, organic material or inorganic material can be used, and the example of material comprises silicone resin, acrylic resin, metal, glass material, ceramic material etc.In the present technology, from the perspective of carrying out drying step under the state that composition is poured in the mould and / or on the embossing sheet, it is preferred to use mould and / or embossing sheet that comprise silicon (such as silicone resin).By using mould and / or embossing sheet that comprise silicon, demoulding property and transferability are improved, and can improve the surface quality of each surface of paper foam material 1 after the moulding.

[0259] (6) Drying step S6

[0260] Drying step S6 is a step of drying as needed after the composition 10 after foaming step S4 is formed in forming step S5. The drying method in drying step S6 can be performed by a combination of one or two or more general drying methods, as long as the effect of the present technology is not damaged. The example of drying method includes natural drying, heating drying, hot air drying, reduced pressure drying, freeze drying, dehumidification drying, microwave drying, light drying (infrared carbon lamp heater drying, infrared ceramic heater drying, etc.) etc.

[0261] An example of a paper foam material 1 manufactured by performing the above steps is Figure 5 、 Figure 10 and Figure 11 The accompanying drawings are shown in place of photographs. Figure 5 The example shown in FIG. 5 is an example in which a silicon-containing embossed sheet is formed and manufactured in the forming step S5 . Figure 10 and Figure 11 The example shown in FIG. 5 is an example in which a mold containing silicon is molded and manufactured in the molding step S5 .

[0262] Figure 12 is a schematic diagram illustrating a method for manufacturing the paper foam material 1 used in the present technology. Figure 12 The manufacturing method shown in is an example of molding using a belt conveyor and an embossed sheet. By using an extruder T (such as a T-die) to allow the composition 10 that has undergone the mixing step S3 and the foaming step S4 to flow onto the embossed sheet E, and in this state, by using a dryer H (such as a heater) to dry the composition, the embossed sheet E is then peeled off from the paper foam material 1, thereby manufacturing the paper foam material 1 used for the packaging material according to the present technology.

[0263] Note that, in Figure 12In the example shown in FIG, the composition 10 on the embossed sheet E is dried using a dryer H so that its shape follows the shape of the embossed sheet E, and the manufactured paper foam material 1 is also formed into a sheet shape after the embossing process. However, it is also possible to form a sheet having the shape of the embossed sheet E by increasing the thickness of the composition 10 poured onto the embossed sheet E. Figure 9 More specifically, by increasing the thickness of the composition 10 poured onto the embossed sheet E, Figure 12 The surface not in contact with the embossed sheet E becomes flat and forms Figure 9 The second surface 112 shown in A, and Figure 12 The surface in contact with the embossed sheet E forms Figure 9 The first surface 111 is shown in A.

[0264] The specific thickness varies depending on the fluidity state of the composition 10, etc. For example, by setting the thickness of the composition 10 poured onto the embossed sheet E to about 2 to 3 mm, it can be formed. Figure 5 The embossed sheet-like paper foam material 1 shown in FIG. 1 can be formed by setting the thickness of the composition 10 poured onto the embossed sheet E to 5 mm or more. Figure 9 A paper foam material of the form shown in FIG1.

[0265] Figure 13 It is a diagram with Figure 12 Schematic diagram of examples of different methods for producing paper foam materials 1 used in the present technology. Figure 13 The manufacturing method shown in is an example of molding a paper foam material by using a belt conveyor and a mold M. The composition 10 that has undergone the mixing step S3 and the foaming step S4 is poured into the mold M using an extruder T (such as a T-die), and in this state, the composition is dried by using a dryer H (such as a heater), and then the paper foam material 1 is peeled off from the mold M, thereby manufacturing the paper foam material 1 for packaging materials according to the present technology.

[0266] At this time, from the perspective of improving moldability and improving the design properties and surface roughness of the paper foam material 1 after it is manufactured, the mold M is preferably provided with holes for releasing air, and a porous sheet P such as a mesh sheet is laid under the mold M. An example of the porous sheet P is a sheet made of a material such as polyvinyl chloride (PVC). By laying the porous sheet P made of polyvinyl chloride (PVC) or the like, the permeability of the composition 10 into the mold M is improved, and molding accuracy can be improved.

[0267] Note that, in Figure 13In the example, the drying step S6 is performed in a state where the composition 10 is poured into the mold M, but the present invention is not limited thereto, and it is also possible to perform rough drying to the extent that the mold M can be removed in a state where the composition 10 is poured into the mold M, and to perform main drying in a state where the composition 10 is removed from the mold M.

[0268] In addition, Figure 13 In the example of , the manufactured paper foam body 1 is peeled off from the mold M, but the present invention is not limited thereto, and the manufactured paper foam body may be separated from the mold M by peeling off the mold M after peeling off the porous sheet P.

[0269] Figure 14 It is a diagram with Figure 12 and Figure 13 Schematic diagram of an example of a method for manufacturing a paper foam material 1 used in the present technology. Figure 14 The manufacturing method shown in FIG is an example of forming a paper foam material using a belt conveyor and a mold M. The composition 10 that has undergone the mixing step S3 and the foaming step S4 is conveyed onto the belt conveyor using an extruder T (such as a T-die), and the mold M is squeezed from above to a desired depth. In this state, the composition is dried using a dryer H (such as a heater), and then the paper foam material 1 is peeled off from the mold M, thereby manufacturing the paper foam material 1 for packaging materials according to the present technology.

[0270] exist Figure 14 In the manufacturing method shown in , by pressing the mold M, the composition 10 located at the hole portion is pushed out and expanded, and the top portion to be a part of the structure 12 can be formed into a round shape. With this arrangement, the shape stability of the manufactured paper foam material 1 can be improved.

[0271] Figure 15 It is a diagram with Figure 12 、 Figure 13 and Figure 14 Schematic diagram of an example of a method for manufacturing a paper foam material 1 used in the present technology. Figure 15 The manufacturing method shown in FIG is an example of forming a paper foam material using a roller R. A portion of a first roller R1 having indentations and protrusions on its surface is immersed in a tank containing a composition 10 that has undergone mixing step S3 and foaming step S4, and the composition 10 is deposited on the surface of the first roller R1. At this time, the indentations and protrusions on the surface of the roller R1 have pores of a sufficiently small size that the composition 10 cannot flow out. By performing suction from the inside of the roller R1, the composition 10 can be deposited on the surface of the first roller R1.

[0272] The composition 10 deposited on the surface of the first roller R1 is subjected to surface conditioning by using the second roller R2 or a band saw (not shown), etc., is roughly dried by using the first dryer H1 (such as a heater), and then removed by using, for example, the third roller R3, etc., and finally dried by using the second dryer H2 (such as a heater), thereby making it possible to manufacture the paper foam material 1 for the packaging material according to the present technology.

[0273] Note that, in Figure 15 In the example shown in FIG. 1 , after rough drying is performed on first roller R1 using first dryer H1, paper foam material 1 is removed from first roller R1 and then subjected to main drying using second dryer H2. However, the present invention is not limited thereto, and paper foam material 1 may be removed from first roller R1 after drying on first roller R1 is completed using first dryer H1. Furthermore, by providing first roller R1 with a heating mechanism, drying can be performed solely using the heat of first roller R1, without using dryer H1.

[0274] [Third embodiment]

[0275] Figure 16 1 is a flow chart of a third embodiment of a method for manufacturing the paper foam material 1 used in the present technology. Figure 17 and Figure 18 1 is a schematic diagram illustrating a third embodiment of the method for producing the paper foam material 1 used in the present technology. The method for producing the paper foam material 1 according to the third embodiment is a method that further performs a humidification step S7 and a lamination step S8 in addition to each step performed by the production method according to the first or second embodiment.

[0276] (7) Humidification step S7

[0277] The wetting step S7 is a step of wetting the dried composition with a liquid before the lamination step S8 described later. By performing the wetting step S7, the adhesion between the dried composition and the foamed composition in the lamination step S8 described later can be improved, and the moldability can also be improved.

[0278] Note that in the manufacturing method according to the present technology, the humidification step S7 is not a necessary step, and the humidification step S7 can be omitted by, for example, applying an adhesive on the stacking surface of the composition after drying and / or the composition after foaming in the stacking step S8, or roughly drying the composition to be stacked and then stacking the incompletely dried composition on the composition after foaming.

[0279] Examples of the liquid used in the humidifying step S7 include water, solutions containing various types of chemicals such as adhesives, and the like, and among these liquids, water is preferably used from the viewpoints of cost and work efficiency.

[0280] As a specific method in the humidification step S7, any method can be used as long as the function and effect of the present technology are not impaired. Examples of the method include a method of spraying a liquid on the laminated surface of the dried composition, a method of immersing the laminated surface of the dried composition in a liquid, and the like.

[0281] (8) Lamination Step S8 (First Lamination Step)

[0282] The lamination step S8 (also referred to as the "first lamination step") is a step of laminating the dried composition on the foamed composition. Figure 16 As shown in the flowchart of FIG. 1 , the first laminating step is a step of laminating the paper foam 1 (composition after drying) manufactured by the manufacturing method according to the first embodiment on the composition after the foaming step on another production line.

[0283] By performing the laminating step S8 , properties such as impact resistance, sound absorption properties, sound insulation properties, shockproof properties, heat insulation properties, and fire resistance properties of the manufactured paper foam body 1 can be improved.

[0284] As the thickness of the composition 10 becomes thicker, the drying time in the drying step S6 becomes longer. Therefore, as in the manufacturing method according to the third embodiment, a paper foam material 1 having a large thickness can be efficiently manufactured by laminating the already manufactured paper foam material 1 (the composition after drying) on ​​the composition after the foaming step on another production line.

[0285] [Fourth embodiment]

[0286] Figure 19 This is a flowchart of a fourth embodiment of the method for producing the paper foam material 1 used in the present technology. The method for producing the paper foam material 1 according to the fourth embodiment is a method in which a coating step S9, a laminating step S10, and a drying step S11 are performed in addition to each step performed by the production method according to the first embodiment or the second embodiment. Note that in Figure 19 In the flowchart of FIG. 1 , a method of further performing the coating step S9 , the lamination step S10 , and the drying step S11 in the manufacturing method according to the second embodiment is exemplified.

[0287] (9) Coating step S9

[0288] The coating step S9 is to apply the composition 10 after the foaming step S4 to the surface of the paper foam material 1 manufactured by the manufacturing method according to the first embodiment. The coating method in the coating step S9 can be performed by one or a combination of two or more general coating methods as long as the effects of the present technology are not impaired. Examples of coating methods include roller coating, kiss coating, spray coating, brush coating, transfer using a die, etc.

[0289] (10) Lamination Step S10 (Second Lamination Step)

[0290] The lamination step S10 (also referred to as the "second lamination step") is to laminate the paper foam material 1 manufactured by the manufacturing method according to the first embodiment onto the surface coated with the composition 10 in the coating step S9. Specifically, in the second lamination step S10, the paper foam material 1, the pre-drying composition 10, and the paper foam material 1 are laminated in this order. At this time, the pre-drying composition 10 sandwiched between the paper foam materials 1 acts as an adhesive, bonding the paper foam materials 1 to each other.

[0291] (11) Drying step S11

[0292] Drying step S11 is a step for drying the laminated sheet after the second lamination step S10. In drying step S11, since the paper foam materials 1 are already dried, the composition 10 sandwiched between the paper foam materials 1 is actually dried. Because the drying method in drying step S11 is similar to the drying method in drying step S6 described above, its description is omitted here.

[0293] As the thickness of the composition 10 becomes thicker, the drying time in the above-mentioned drying step S6 becomes longer. Therefore, as in the manufacturing method according to the second embodiment, the paper foam material 1 having a large thickness can be efficiently manufactured by performing the drying step S11 in a state where the manufactured paper foam materials 1 are bonded together by using the composition 10 before drying.

[0294] 3. Composite materials 2

[0295] Figure 20 and Figure 21 1 is a drawing-substitute photograph illustrating an example of a composite material 2 that can be used as a packaging material according to the present technology. The composite material 2 according to the present technology includes the paper foam material 1 used in the present technology described above and a base material 21.

[0296] (1) Base material 21

[0297] The substrate 21 of the composite material 2 according to the present technology is not particularly limited as long as the effect of the present technology is not impaired, and a substrate 21 using any material can be used. As materials for the substrate 21 that can be used in the present technology, waste paper (such as newspapers, magazines, books, and corrugated cardboard), pulp (such as bamboo, bagasse, and straw), woven fabrics (such as cotton fabrics, wool fabrics, and chemical fiber fabrics), resins, etc. can be used. In the present technology, it is preferred to use a substrate 21 containing waste paper and / or pulp. By using a fiber material containing waste paper and / or pulp, recyclability can be improved. Waste paper may include, for example, newspapers, magazines, books, corrugated cardboard, etc. as described above. Pulp may include wood, non-wood, etc. Examples of non-wood may include bamboo, bagasse, straw, etc.

[0298] exist Figure 20 and Figure 21 In the example of , a pulp mold is used as the base material 21. Pulp molds are recyclable base materials 21, including waste paper such as corrugated cardboard, but they suffer from a lack of recoverability and low cushioning properties. However, by combining a pulp mold with the paper foam material 1 used in this technology, a composite material 2 imparted with recoverability can be obtained, and cushioning properties can also be improved.

[0299] The method for bonding the paper foam material 1 to the substrate 21 is not particularly limited, as long as the effects of the present technology are not impaired. For example, bonding can be performed with an adhesive layer interposed therebetween, or bonding can be performed by bonding the composition 10 to the substrate 21 before drying and then drying the composition. Note that since the adhesive layer is the same as the adhesive layer 32 of the multilayer structure 3 described later, its description is omitted here.

[0300] (2) Application of composite material 2

[0301] The use of the above-mentioned composite material 2 used in the present technology is not particularly limited, and the composite material 2 can be appropriately used for, for example, cushioning materials, packaging materials, sound-absorbing materials, sound-insulating materials, soundproof materials, shock-proof materials, heat-insulating materials, fire-resistant materials, wallpaper, aromatic materials, deodorizing materials, seat pads for automobiles, etc., maintenance materials, agricultural materials, etc.

[0302] Furthermore, if a recyclable material is used as the base material 21, its use as a recycled material can also be expected. Note that specific examples of the composite material 2 according to the present technology are the same as the specific use examples of the paper foam material 1 described above, so their description is omitted here.

[0303] 4. Manufacturing method of composite material 2

[0304] Figure 22Flowchart of a first embodiment of a method for manufacturing a composite material 2 used in the present technology. The method for manufacturing a composite material 2 according to the present technology is a method that performs at least a foaming step S4, an attaching step S12, and a drying step S13. In addition, as needed, a fiber separation treatment step S1, a binder mixing step S2, a mixing step S3, etc. may also be performed. The details of each step will be described below. Note that because the fiber separation treatment step S1, the binder mixing step S2, the mixing step S3, and the foaming step S4 are the same as those in the above-mentioned method for manufacturing the paper foam material 1 used in the present technology, their description is omitted here.

[0305] (1) Attachment step S12

[0306] The attaching step S12 is a step of attaching the composition 10 after the foaming step S4 to the substrate 21 before the drying step S13 described later. In the attaching step S12, the specific method is not particularly limited as long as the composition 10 before drying can be in contact with another substrate 21. Examples of the method include a method of attaching by laminating the composition 10 before drying on the substrate 21, a method of attaching by applying the composition 10 before drying to the substrate 21, a method of attaching by filling a predetermined portion of the substrate 21 with the composition 10 before drying, and the like.

[0307] (2) Drying step S13

[0308] Drying step S13 is a step for drying the composition 10 after attaching step S12. By drying the composition 10 before drying while attached to another substrate 21, the paper foam material 1 is formed while being adhered to the substrate 21. That is, a composite material 2 including the paper foam material 1 and the substrate 21 can be produced. Because the drying method in drying step S13 is similar to the drying method in drying step S6 described above, its description is omitted here.

[0309] Figure 23 is a schematic diagram illustrating an example of a method for manufacturing the composite material 2 according to the present technology. Figure 23 The manufacturing method shown in the figure is an example of forming a composite material using a belt conveyor. The composite material 2 according to the present technology can be manufactured by pouring the composition 10 that has undergone the mixing step S3 and the foaming step S4 into the substrate 21 using an extruder T (such as a T-die) and drying the composition in this state using a dryer H (such as a heater).

[0310] At this time, for example, if a substrate 21 including a material having air permeability such as a pulp mold is used as the substrate 21, air can be released from the substrate 21 when the composition 10 is poured into the substrate 21, whereby moldability can be improved and the design and surface roughness of the produced paper foam material 1 can be improved.

[0311] Figure 24 It is a diagram with Figure 23 Schematic diagram of examples of different methods for manufacturing composite materials 2 according to the present technology. Figure 24 The manufacturing method shown in the figure is an example of performing injection molding using a mold. For example, in a state where the base material 21 is set in the mold D1 on the fixed side using the mold on the movable side, the composite material 2 according to the present technology can be manufactured by injecting and drying the composition 10 that has undergone the mixing step S3 and the foaming step S4.

[0312] Figure 25 It is a diagram with Figure 23 and Figure 24 Schematic diagram of an example of a method for manufacturing a composite material 2 according to the present technology. Figure 25 The manufacturing method shown in is a method of manufacturing the composite material 2 according to the present technology by injecting the composition 10 that has undergone the mixing step S3 and the foaming step S4 onto the substrate 21 in a desired form and drying the composition.

[0313] exist Figure 25 In the example shown in , the composition 10 is injected onto the substrate 21 in a rod shape, but the present invention is not limited to this form, and the composition can be designed in a free form based on the purpose, the function required for the composite material 2, etc., and designability can be imparted.

[0314] 5. Multilayer structure 3

[0315] Figure 26 1 is a schematic diagram illustrating a first embodiment of a multilayer structure 3 that can be used for packaging materials according to the present technology. The multilayer structure 3 according to the present technology includes a paper foam material layer 31 including the paper foam material 1 used in the present technology described above; and an adhesive layer 32.

[0316] (1) Adhesive layer 32

[0317] The material forming the adhesive layer 32 is not particularly limited, as long as it can adhere the paper foam materials 1 to each other or to another substrate 21. Various materials having adhesive properties can be used. For example, an adhesive comprising a resin can be used. Examples of resins forming the adhesive include polyurethane resins, polyolefin resins, acrylic resins, epoxy resins, and the like. These resins can be used alone or in combinations of two or more. Furthermore, as in the method for manufacturing the paper foam material 1 according to the second embodiment described above, a foam mixture before drying can be used as the adhesive layer.

[0318] (2) Form of multilayer structure 3

[0319] The multilayer structure 3 used in the present technology only needs to include at least one or more paper foam material layers 31 and one or more adhesive layers 32, and the number of each layer is not particularly limited. Figure 26 As in the multilayer structure 3 according to the first embodiment shown in , the multilayer structure can have a structure including a paper foam material layer 31 and an adhesive layer 32, and for example, the paper foam material layer 31 and another substrate 21 not shown can be bonded together with the adhesive layer 32 located therebetween.

[0320] In addition, for example, as in Figure 27 As in the multilayer structure 3 according to the second embodiment shown in FIG, a structure may be adopted in which paper foam material layers 31 are bonded to each other with an adhesive layer 32 interposed therebetween.

[0321] Furthermore, the paper foam material layer 31 and the adhesive layer 32 may have two or more layers, and for example, as in Figure 28 As in the multilayer structure 3 according to the third embodiment shown in FIG, a structure in which different numbers of layers are freely combined according to the purpose of the multilayer structure 3 or the like can be adopted.

[0322] Furthermore, for example, Figure 28 The multilayer structure 3 according to the third embodiment shown in FIG. Figure 28 The line AA in is bent to have a Figure 29 The form of the multilayer structure 3 according to the fourth embodiment is shown in FIG.

[0323] In addition, as in Figure 30 As in the multilayer structure 3 according to the fifth embodiment shown in FIG, for example, in the case where the multilayer structure 3 is used as a packaging material, a stacked structure (indicated by broken lines in the figure) can be formed according to the shape of a product to be packaged.

[0324] (3) Application of multilayer structure 3

[0325] The use of the multilayer structure 3 used in the present technology is not particularly limited, and the multilayer structure 3 can be appropriately used for, for example, cushioning materials, packaging materials, sound-absorbing materials, sound-insulating materials, sound-proof materials, shock-proof materials, heat-insulating materials, fire-resistant materials, wallpapers, aromatic materials, deodorizing materials, car seat pads, maintenance materials, agricultural materials, etc.

[0326] Furthermore, if a recyclable material is used as the above-mentioned adhesive layer 32, use as a recycled material can also be expected.

[0327] The multilayer structure 3 used in the present technology can be used for various types of applications in a state of being combined with a plurality of multilayer structures. Figure 31 As in the multilayer structure 3 according to the sixth embodiment shown in FIG, in the case where the multilayer structure 3 is used as a packaging material, a plurality of multilayer structures 3 can be used to package a product to be packaged (indicated by broken lines in the figure).

[0328] 6. Method for manufacturing multilayer structure 3

[0329] Figure 32 This is a flow chart of a first embodiment of a method for manufacturing a multilayer structure 3 used in the present technology. The method for manufacturing a multilayer structure 3 according to the present technology is a method that performs at least a foaming step S4, a drying step S6, and a lamination step S15. In addition, as needed, a fiber separation treatment step S1, a binder mixing step S2, a mixing step S3, a molding step S5, an adhesive coating step S14, a drying step S16, a molding step S17, etc. may also be performed. The details of each step will be described below. Note that because the fiber separation treatment step S1, the binder mixing step S2, the mixing step S3, the foaming step S4, and the molding step S5 are the same as the fiber separation treatment step S1, the binder mixing step S2, the mixing step S3, the foaming step S4, and the molding step S5 of the aforementioned method for manufacturing the paper foam material 1 used in the present technology, their description is omitted here.

[0330] (1) Adhesive coating step S14

[0331] The adhesive coating step S14 is a step of coating an adhesive on the surface of the paper foam material 1 produced by the drying step S6. Since the coating method in the adhesive coating step S12 is similar to the coating method in the above-mentioned coating step S9, its description is omitted here.

[0332] (2) Lamination Step S15 (Third Lamination Step)

[0333] The lamination step S15 (hereinafter also referred to as the "third lamination step") is a step of laminating the paper foam materials 1 after the drying step with the adhesive layer interposed therebetween. That is, in the third lamination step S15, the paper foam materials 1, the adhesive, and the paper foam materials 1 are laminated in this order.

[0334] (3) Drying step S16

[0335] The drying step S16 is a step of drying the adhesive after the third lamination step S15 to form the adhesive layer 32. Since the drying method in the drying step S16 is similar to the drying method in the above-described drying step S6, description thereof is omitted here.

[0336] (4) Molding step S17

[0337] The forming step S17 is a step of forming the manufactured multilayer structure 3 into a desired shape. For example, as described above, Figure 28 The multilayer structure 3 according to the third embodiment shown in FIG. Figure 28 The line AA in is bent to have a Figure 29 The form of the multilayer structure 3 according to the fourth embodiment is shown in . The molding method performed in the molding step S17 is not limited to the method of performing molding by bending, and may also include molding by cutting, molding by bonding, molding by lamination, molding by a combination of the above methods, etc.

[0338] Note that the present technology can also have the following configurations. (1)

[0340] A paper foam material comprising:

[0341] fibrous materials including waste paper and / or pulp;

[0342] Adhesive;

[0343] Sodium bicarbonate; and

[0344] Surfactants, and include:

[0345] Water-soluble softeners; and

[0346] Carboxylic acid anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group. (2)

[0348] The paper foam material according to (1), wherein the molar ratio of the carboxylic anhydride to the softening agent is 0.01 to 2. (3)

[0350] The paper foam material according to (1) or (2), wherein the saturated hydrocarbon group and / or the unsaturated hydrocarbon group has 12 to 24 carbon atoms. (4)

[0352] The paper foam material according to any one of (1) to (3), wherein the carboxylic acid anhydride is an alkenyl carboxylic acid anhydride. (5)

[0354] The paper foam material according to (4), wherein the alkenyl carboxylic acid anhydride is octadecenyl carboxylic acid anhydride. (6)

[0356] The paper foam material according to (5), wherein the octadecenylcarboxylic anhydride is octadecenylsuccinic anhydride. (7)

[0358] The paper foam material according to any one of (1) to (6), wherein the softener is a polyol. (8)

[0360] The paper foam material according to any one of (1) to (7), further comprising an anti-discoloration agent. (9)

[0362] The paper foam material according to (8), wherein the anti-discoloration agent comprises alum. (10)

[0364] The paper foam material according to any one of (1) to (9), further comprising an antimicrobial agent. (11)

[0366] The paper foam material according to (10), wherein the antimicrobial agent comprises potassium sorbate. (12)

[0368] The paper foam material according to any one of (1) to (11), wherein the binder comprises polyvinyl alcohol. (13)

[0370] The paper foam material according to any one of (1) to (12), wherein the surfactant comprises a polyoxyethylene alkyl ether. (14)

[0372] The paper foam material according to any one of (1) to (13), wherein the paper foam material has a sheet shape subjected to one or more processes selected from embossing, dimple processing, protrusion processing, and hollow processing. (15)

[0374] The paper foam material according to any one of (1) to (14), wherein the paper foam material is bonded to the substrate with an adhesive layer interposed between the paper foam material and the substrate. (16)

[0376] The paper foam material according to any one of (1) to (15), wherein the paper foam material is used for one or more applications selected from the group consisting of a cushioning material application, a packaging material application, a sound absorbing material application, a heat insulating material application, and a fire-resistant material application. (17)

[0378] A method for manufacturing a paper foam material, the method comprising:

[0379] A mixing step of mixing a composition comprising:

[0380] Fibrous material comprising waste paper and / or pulp,

[0381] Binder,

[0382] Sodium bicarbonate, and

[0383] surfactants, and including

[0384] Water-soluble softeners, and

[0385] Carboxylic anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group; and

[0386] A foaming step of foaming the composition. (18)

[0388] The method for producing a paper foam material according to (17), further comprising a molding step of molding the composition by using a mold and / or an embossed sheet. (19)

[0390] The method for producing a paper foam material according to (17) or (18) further comprises a drying step of drying the foamed composition. (20)

[0392] The method for producing a paper foam material according to (18) further comprises a laminating step of laminating the dried composition on the foamed composition. (twenty one)

[0394] The method for producing a paper foam material according to (20) further comprises a wetting step of wetting the dried composition with a liquid before the lamination step.

[0395] Example

[0396] Hereinafter, the present technology will be described in more detail based on examples. Note that the examples to be described below merely describe representative embodiments of the present invention, and the scope of the present technology will not be narrowed by the examples.

[0397] <Experimental Example 1>

[0398] In Experimental Example 1, the influence of the different materials used for the paper foam material on the physical properties of various types was investigated. Note that in this experimental example, octadecenylcarboxylic anhydride was used as an example of the alkenylcarboxylic anhydride.

[0399] (1) Manufacturing of paper foam materials

[0400] The materials shown in Tables 1 and 2 below were weighed and mixed, and then a composition 10 was prepared by stirring and mixing using a foaming machine. The composition 10 was stretched into a sheet and naturally dried for 20 hours under the conditions of a temperature of 23° C. and a humidity of 50% to produce paper foam materials of a control and samples 1 to 8.

[0401] [Table 1]

[0402]

[0403]

[0404] (2) Evaluation

[0405] Each foam material was evaluated for impact resistance, recovery after impact, flexibility (moisture retention properties), and migration properties according to the following evaluation criteria.

[0406] [Impact resistance]

[0407] For each foam material produced based on JIS standard Z0235, a test piece with a length of 150±5mm, a width of 150±5mm, and a thickness of 50±5mm was prepared. After being placed at a temperature of 23±2°C and a humidity of 50±5% for more than 16 hours, the state of the foam material when a weight was freely dropped from a height of 60cm was observed.

[0408] ○: The foam material is not broken

[0409] ×: Foam material ruptured

[0410] [Resilience after impact]

[0411] After the impact test, the state of the foam material was observed after the iron ball was removed.

[0412] ○: The foam material immediately returns to its original shape

[0413] ×: The foam material has not returned to its original shape after a period of time

[0414] [Flexibility (moisturizing properties)]

[0415] The cushioning properties of the manufactured foam materials were evaluated according to the following criteria.

[0416] ○: Maintains cushioning properties

[0417] ×: Loss of cushioning properties

[0418] [Migration characteristics]

[0419] The manufactured foam material was stored in contact with a stainless steel plate at a high temperature of 90 to 95% and a high humidity of 65±2° C. for 24 hours, and then the occurrence of “migration of the foam material” to the plate was observed.

[0420] 1: A full migration occurs

[0421] 2: Migration occurs

[0422] 3: Migration occurred, but can be cleared

[0423] 4: Minor migration occurs

[0424] 5: No migration observed

[0425] (3) Results

[0426] The results are shown in Table 2.

[0427] [Table 2]

[0428]

[0429] As shown in Table 2, in the control product to which no softener was added, the evaluation of migration characteristics was good, but the evaluation of moisturizing characteristics was poor, and the foaming property was poor. On the other hand, as shown in Samples 1 to 8, by adding a softener, good foaming and drying conditions were achieved, and the moisturizing characteristics were improved, and the elastic effect and cushioning characteristics of the foam material were improved.

[0430] Furthermore, as shown in Samples 1 to 7, it was found that the degree of "migration" from the foam material to the object in contact varied depending on the type of softener. Specifically, Samples 3 to 6 had a higher transferability evaluation than Samples 1 and 2 using glycerin or ethylene glycol, that is, it was shown that the occurrence of "migration" could be further suppressed. 1 、R 2 -N-CO-NR 3 、R 4 (R 1 to R 4 : H or a saturated and / or unsaturated hydrocarbon group having 1 to 4 carbon atoms), or propylene glycol or butylene glycol as a polyol having 3 to 15 water-soluble carbon atoms and wherein the relationship between the number of carbon atoms and the number of hydroxyl groups (OH) in the molecular structure of the polyol is such that the number of hydroxyl groups is less than the number of carbon atoms.

[0431] Furthermore, as shown in the results of Samples 1 and 8, it has been revealed that even in the case of using glycerin having a high incidence of “migration”, the occurrence of “migration” can be suppressed by using a carboxylic anhydride in combination.

[0432] <Experimental Example 2>

[0433] In Experimental Example 2, the influence of the difference in fiber materials on the physical properties of various types was investigated.

[0434] (1) Manufacturing of paper foam materials

[0435] By using the materials shown in Table 3 and Table 4 below, a paper foam material was manufactured in a similar manner to that in Experimental Example 1.

[0436] [Table 3]

[0437]

[0438]

[0439] (2) Evaluation

[0440] [tensile strength]

[0441] The tensile strength of each manufactured paper foam material was measured in accordance with JIS Z1702.

[0442] [Manufacturability]

[0443] For each paper foam material manufactured, the manufacturability of each paper foam material was evaluated according to the following evaluation criteria.

[0444] ⊙: Very good (Stable foaming and discharge were observed from the beginning to the end of slurry discharge. The turbine mixing head rotated continuously without any problems.)

[0445] ○: Good (At the start of slurry discharge, stable foaming and discharge were observed, but due to specific gravity, as the remaining amount in the hopper decreased, feeding problems occurred. This problem was solved by adding a heavy object and hot water. The turbine mixing head continued to rotate without any problems.)

[0446] ×: Poor (Stable foaming and discharge were observed at the beginning of slurry discharge, but the discharge amount gradually decreased and eventually caused clogging of the turbine mixing head.)

[0447] [Processability]

[0448] For each of the manufactured paper foam materials, the processability of each paper foam material was evaluated according to the following evaluation criteria.

[0449] ⊙: Very good (The slurry applied from the T-die to the mold plate can be foamed uniformly and stably formed. Regardless of the size of the crushed mesh, the solidification settlement after drying is within about half of the applied amount, and the cushioning properties are maintained.)

[0450] ○: Good (The slurry applied from the T-die to the die plate can be uniformly foamed and stably molded, but the amount of solidification and sedimentation varies depending on the pulverization mesh diameter. Therefore, there are differences in thickness and cushioning properties.)

[0451] ×: Poor (The slurry could not be discharged and the turbine mixing head was clogged, so molding could not be performed.)

[0452] (3) Results

[0453] The results are shown in Table 4.

[0454] [Table 4]

[0455]

[0456]

[0457] (4) Discussion

[0458] From the results shown in Table 4, although there were some differences in physical properties depending on the type of fiber material, the evaluations of all examples were within an acceptable range.

[0459] <Experimental Example 3>

[0460] In Experimental Example 3, the influence of differences in the shape and the like of the foam material 1 according to the present technology on the impact characteristics was investigated.

[0461] (1) Manufacturing of paper foam materials

[0462] Paper foam materials were produced in a similar manner to Experimental Example 1 using the materials shown in Table 5 below, and processed into the shapes shown in Table 6 below (Samples 9 to 12). As controls, examples using corrugated cardboard used as existing packaging materials (Controls 2 to 4) and an example using expanded polystyrene (Control 5) were prepared.

[0463] [Table 5]

[0464]

[0465]

[0466] (2) Evaluation

[0467] [Cushioning characteristics]

[0468] Regarding the cushioning properties of the manufactured paper foam material, the cushioning properties were measured in accordance with JIS Z0235.

[0469] [Overall confirmation]

[0470] ⊙: Very good as a cushioning material for heavy objects

[0471] ○: Good as a cushioning material for heavy objects

[0472] Δ: Generally used as a cushioning material for light objects

[0473] (3) Results

[0474] The results are shown in Table 6.

[0475] [Table 6]

[0476]

[0477]

[0478] *1 Pulp mold with a rounded bottom surface

[0479] *2 Pulp mold with a square bottom surface

[0480] (4) Discussion

[0481] As shown in Table 6, it is shown that the paper foam material according to the present technology has cushioning properties comparable to those of the examples using corrugated cardboard as the existing packaging material (Controls 2 to 4) and the example using expanded polystyrene (Control 5).

[0482] <Experimental Example 4>

[0483] The sound absorbing effect in the case where the paper foam material according to the present technology is used as the sound absorbing material is investigated.

[0484] (1) Manufacturing of sound-absorbing materials

[0485] By using the following Table 7 and Figure 33 The materials shown in the example are used to make paper foam materials in a similar manner to that of Experimental Example 1, and are processed into Figure 33 to create a sound absorbing material.

[0486] [Table 7]

[0487]

[0488]

[0489] (2) Evaluation

[0490] The sound transmission loss of the manufactured sound absorbing material was measured.

[0491] (3) Results and Discussion

[0492] The results are Figure 33 As shown in Figure 33 As shown in the results, the paper foam material according to the present invention has sound absorption performance comparable to that of glass wool. Furthermore, when a mixed material of bamboo, bagasse, and publicly collected waste paper is used as the fiber material, or when bagasse is used as the fiber material, the sound absorption performance is slightly higher than that of glass wool, and by using it as a composite material, the sound absorption performance can be improved to that comparable to that of styrene foam.

[0493] <Experimental Example 5>

[0494] In Experimental Example 5, the heat insulating effect in the case where the paper foam material according to the present technology was used as the heat insulating material was investigated.

[0495] (1) Manufacturing of thermal insulation materials

[0496] By using the materials shown in the following Table 8 and Table 9, a paper foam material was manufactured in a manner similar to Experimental Example 1. As controls, styrene foam, glass wool, and cellulose fiber were prepared.

[0497] [Table 8]

[0498]

[0499]

[0500] (2) Evaluation

[0501] The thermal resistance and thermal conductivity of the manufactured thermal insulation materials were measured.

[0502] (3) Results

[0503] The results are shown in Table 9.

[0504] [Table 9]

[0505]

[0506]

[0507] (4) Discussion

[0508] It was found that the thermal insulation effect of bamboo sample 14 and bagasse sample 15 was comparable to or higher than that of cellulose nanofiber. In addition, it was found that the thermal insulation effect of corrugated cardboard sample 13 and virgin mixed material (OBM) sample 16 was slightly lower than that of cellulose nanofiber, but comparable to that of cellulose nanofiber.

[0509] <Experimental Example 6>

[0510] In Experimental Example 6, the fire-resistant / flame-retardant effect when the paper foam material according to the present technology is used as a fire-resistant / flame-retardant material was investigated.

[0511] (1) Manufacture of refractory / flame retardant materials

[0512] By using the materials shown in Table 10 below, a fire-resistant material / flame-retardant material was manufactured by adding a predetermined amount of a fire-resistant agent when manufacturing a paper foam material in a similar manner to Experimental Example 1.

[0513] [Table 10]

[0514]

[0515]

[0516] (2) Evaluation

[0517] [Flame retardant properties]

[0518] The flame retardant test of the manufactured refractory / flame retardant materials was carried out according to JIS L1091 A-2.

[0519] (3) Results

[0520] The results are shown in Table 11.

[0521] [Table 11]

[0522]

[0523] (4) Discussion

[0524] As shown in Table 11, it was found that the fire resistant / flame retardant effect was exhibited by including the fire resistant agent in the paper foam material according to the present technology.

[0525] <Experimental Example 7>

[0526] In Experimental Example 7, a fragrance material / deodorizing material was manufactured by using the paper foam material according to the present technology.

[0527] (1) Manufacture of fragrance / deodorizing materials

[0528] By using the materials shown in Table 12 below, when manufacturing a paper foam material in a manner similar to Experimental Example 1, an aroma material / deodorizing material was manufactured by adding a prescribed amount of coffee grounds.

[0529] [Table 12]

[0530]

[0531] The fragrance material / deodorant material manufactured Figure 34 As shown in Figure 34 As shown in , a fragrance material / deodorizing material can be manufactured by using the foam material according to the present technology.

[0532] <Experimental Example 8>

[0533] In Experimental Example 8, the paper foam material according to the present technology was subjected to a coloring treatment.

[0534] (1) Manufacturing of paper foam materials

[0535] A paper foam material was manufactured in a similar manner to Experimental Example 1 using the materials shown in Table 13 below.

[0536] [Table 13]

[0537]

[0538] The paper foam material produced is Figure 35 As shown in Figure 35 As shown in , the paper foam material according to the present technology can be colored.

[0539] <Experimental Example 9>

[0540] In Experimental Example 9, in order to improve the durability of the surface of the paper foam material according to the present technology, a composite material in which natural fibers were laminated on the surface was manufactured.

[0541] (1) Manufacturing of composite materials

[0542] By using the materials shown in the above Table 5, a paper foam material was manufactured in a similar manner to Experimental Example 1. In the foaming step of the paper foam material, by laminating and integrally attaching with natural fibers, a composite material was manufactured.

[0543] The composite materials produced Figure 36 As shown in Figure 36 As shown in [ 1 ], a paper foam material (composite material) with improved surface durability can be produced. It is believed that through textile processes such as fiber, knitting, and weaving, the paper foam material according to the present technology can be given durability, three-dimensional responsiveness using a single material, decorative properties, and the like. In addition, by using a textile made of the same material as the paper foam, recycling can be facilitated.

[0544] <Experimental Example 10>

[0545] In Experimental Example 10, the manufactured paper foam material was recycled and the paper foam material was manufactured again.

[0546] (1) Recovery method

[0547] Measure the weight of the used paper foam material and determine the total amount of fiber material according to the recipe. Grind the used paper foam material to a certain degree (see Figure 37 A to C), then washed with water to a fibrous material state and dehydrated (see Figure 37 D). At this time, if disinfection or sterilization is desired, boiling or high-temperature heating (microwave heating, etc.) may also be performed. The weight and moisture content of the dehydrated fiber material are determined, and the fiber material is mixed with other ingredients in a content obtained by subtracting the moisture content from the paper foam material formula, and a mixed composition is prepared again (see Figure 37 E), and the paper foam material was recovered in a similar manner to Experimental Example 1.

[0548] <Experimental Example 11>

[0549] In Experimental Example 11, soil reduction was performed on the paper foam material according to the present technology.

[0550] (1) Soil reduction and plant growth

[0551] [Soil restoration]

[0552] The used paper foam material according to the present technology was mixed with humus, and rehydration and temperature control were appropriately performed, and it was confirmed that it was restored to soil after about two months. Figure 38 Shown in. Figure 38 A shows an example using plain paper, and Figure 38 B shows an example of using a paper foam material according to the present technology. Figure 38 As shown in , in an example using a paper foam material according to the present technology, the growth of plants became possible after approximately two months.

[0553] [Growing plants from seeds and seedlings]

[0554] The paper foam material is washed with water to a state close to that of the fiber material, and the growth is performed according to the cultivation method of each plant, taking into account moisture, photosynthesis, temperature and nutrient components. Figure 39 As shown in Figure 39 As shown in , it is shown that plants can be grown by using paper foam materials according to the present technology.

[0555] [Hydroponic cultivation]

[0556] When using dry paper foam material, moisten the material used as the floor with water and sow seeds in it, rehydrate the seeds in a warm and dark place for several days, and cultivate the seeds under clean conditions, and perform photosynthesis as they grow, and the seeds turn green and grow. Figure 40 As shown in Figure 40As shown in , it is shown that plants can be grown through hydroponic cultivation by using the paper foam material according to the present technology.

[0557] [Mushroom bed cultivation]

[0558] The paper foam material is washed with water and dehydrated to form a fibrous material containing a certain amount of moisture, and then sterilized by using heat, alcohol, etc. While taking care to prevent the incorporation of various unwanted bacteria, the mycelium is mixed with nutrients (rice bran, wheat bran, tea dregs, food compost, etc.) in a mixing amount suitable for the bacteria, and the mixture is placed in a sealed container (bottle, bag, box, etc.) provided with a vent to prevent the entry of unwanted bacteria, and the bacteria are grown in a dark place at a constant temperature for a period of time. After the mycelium covers the entire interior of the container, the container is moved to a bright place and the mycelium is subjected to environmental stimulation, such as by taking it out of the container and rinsing it with cold water or lowering the outside temperature. As a result, the fruiting body can be grown within two to three weeks. The results are in Figure 41 As shown in Figure 41 As shown in , it is shown that by using the paper foam material according to the present technology, plants can be grown through mushroom bed cultivation.

[0559] Reference Signs List

[0560] Paper foam material: 1

[0561] Base: 11

[0562] First surface of base layer 11:111

[0563] Second surface of base layer 11:112

[0564] Structure: 12

[0565] Composition: 10

[0566] Fiber separation process step: S1

[0567] Binder mixing step: S2

[0568] Mixing step: S3

[0569] Foaming step: S4

[0570] Molding step: S5

[0571] Drying steps: S6, S11, S13

[0572] Humidification step: S7

[0573] Lamination step: S8 (first lamination step)

[0574] Embossed board: E

[0575] Mold: M

[0576] Porous sheet: P

[0577] Extruder: T

[0578] Dryer: H

[0579] Coating step: S9

[0580] Lamination step: S10 (second lamination step)

[0581] Composite materials (packaging materials): 2

[0582] Base material: 21

[0583] Attachment step: S12

[0584] Adhesive coating step: S14

[0585] Lamination step: S15 (third lamination step)

[0586] Multilayer structure (packaging material): 3

[0587] Foam material layers: 31

[0588] Adhesive layers: 32

Claims

1. A paper foam material comprising: fibrous materials including waste paper and / or pulp; Adhesive; Sodium bicarbonate; as well as Surfactants, and include: Water-soluble softeners; as well as Carboxylic acid anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group.

2. The paper foam material according to claim 1, wherein the molar ratio of the carboxylic anhydride to the softener is 0.01 to 2. 3 . The paper foam material according to claim 1 , wherein the saturated hydrocarbon group and / or the unsaturated hydrocarbon group has a carbon atom number of 12 to 24.

4. The paper foam material of claim 1, wherein the carboxylic acid anhydride is an alkenyl carboxylic acid anhydride.

5. The paper foam material according to claim 4, wherein the alkenyl carboxylic acid anhydride is octadecenyl carboxylic acid anhydride.

6. The paper foam material according to claim 5, wherein the octadecenyl carboxylic anhydride is octadecenyl succinic anhydride.

7. The paper foam material of claim 1, wherein the softener is a polyol.

8. The paper foam material of claim 1 further comprising an anti-stainsant.

9. The paper foam material of claim 8, wherein the anti-stains agent comprises alum.

10. The paper foam material of claim 1 further comprising an antimicrobial agent.

11. The paper foam material of claim 10, wherein the antimicrobial agent comprises potassium sorbate.

12. The paper foam material of claim 1, wherein the binder comprises polyvinyl alcohol.

13. The paper foam material of claim 1, wherein the surfactant comprises a polyoxyethylene alkyl ether.

14. The paper foam material according to claim 1, wherein the paper foam material has a sheet shape processed by one or more processes selected from the group consisting of embossing, dimple processing, protrusion processing, and hollow processing.

15. The paper foam material of claim 1, wherein the paper foam material is bonded to the substrate with an adhesive layer interposed between the paper foam material and the substrate.

16. The paper foam material according to claim 1, wherein the paper foam material is used for one or more applications selected from the group consisting of a cushioning material application, a packaging material application, a sound absorbing material application, a heat insulating material application, and a fire resistant material application.

17. A method for manufacturing a paper foam material, the method comprising: A mixing step of mixing a composition comprising: Fibrous material comprising waste paper and / or pulp, Binder, Sodium bicarbonate, and surfactants, and including Water-soluble softeners, and Carboxylic anhydrides having a saturated hydrocarbon group and / or an unsaturated hydrocarbon group; and A foaming step of foaming the composition.

18. The method for manufacturing a paper foam material according to claim 17, further comprising a molding step of molding the composition by using a mold and / or an embossed sheet.

19. The method for producing a paper foam material according to claim 17, further comprising a drying step of drying the foamed composition.

20. The method for producing a paper foam material according to claim 19, further comprising a laminating step of laminating the dried composition on the foamed composition.

21. The method for producing a paper foam material according to claim 20, further comprising a wetting step of wetting the dried composition with a liquid before the laminating step.

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