Radio wave shielding body and adhesive composition

Abstract

The present invention provides a radio wave shielding body which contains a cationic group-containing polymer that has a cationic group in the polymer chain. The present invention also provides an adhesive composition which contains water and a cationic group-containing polymer that has a cationic group in the polymer chain, wherein the content ratio of the cationic group-containing polymer in the adhesive composition is 55% by weight to 95% by weight (inclusive), and the content ratio of the water in the adhesive composition is 5% by weight to 45% by weight (inclusive).

Description

Radio wave shield and adhesive composition

[0001] The present invention relates to a radio wave shielding material containing a cationic group-containing polymer having cationic groups in the polymer chain, and also to an adhesive composition containing a cationic group-containing polymer having cationic groups in the polymer chain.

[0002] BACKGROUND ART Composite materials, which are made by blending an insulating material such as a resin with a conductive material, are known to be used as electromagnetic wave absorbing materials in the fields of electricity and communications.

[0003] For example, Patent Document 1 proposes an electromagnetic wave absorbing material that comprises a fibrous carbon nanostructure and an insulating material, and in which the content C of the fibrous carbon nanostructure is 5 parts by mass or more and 15 parts by mass or less when the content of the insulating material is 100 parts by mass, or in which the content C is 0.3 parts by mass or more and 0.8 parts by mass or less when the fibrous carbon nanostructure is a fibrous carbon nanostructure that exhibits an upwardly convex t-plot obtained from an adsorption isotherm, and that absorbs electromagnetic waves in a frequency range above 20 GHz.

[0004] The technology disclosed in Patent Document 1 is a technology in which fibrous carbon nanostructures are contained in an insulating polymer as an insulating material, and radio waves or electromagnetic waves are absorbed by the action of the fibrous carbon nanostructures, and the insulating polymer as an insulating material is used to hold the fibrous carbon nanostructures and form them into a predetermined shape. In other words, the technology disclosed in Patent Document 1 is not a technology in which radio waves or electromagnetic waves are absorbed by an insulating polymer as an insulating material.

[0005] International Publication No. 2017 / 110096

[0006] An object of the present invention is to provide a radio wave shielding material having excellent radio wave shielding properties. Another object of the present invention is to provide a pressure-sensitive adhesive composition that can achieve excellent adhesiveness and strength and that can be easily peeled off after use.

[0007] The present inventors have conducted studies to achieve the above object and have found that a cationic group-containing polymer having cationic groups in the polymer chain has excellent radio wave shielding properties, which led to the completion of the present invention. The present inventors have also found that a composition containing a cationic group-containing polymer having cationic groups in the polymer chain and water in a specific ratio can achieve excellent adhesive properties and strength and can be easily peeled off after use, which led to the completion of the present invention.

[0008] That is, the present invention relates to the following: [1] A radio wave shield comprising a cationic group-containing polymer having cationic groups in the polymer chain. [2] The radio wave shield according to [1], comprising 1 to 100% by weight of the cationic group-containing polymer. [3] The radio wave shield according to [1] or [2], which shields radio waves having a frequency of 1 GHz or more and 300 THz or less. [4] The radio wave shield according to any of [1] to [3], further comprising an exterior. [5] A sheet comprising the radio wave shield according to any of [1] to [4]. [6] A partition member comprising the radio wave shield according to any of [1] to [4]. [7] The partition member according to [6], which is a screen, humidity conditioner, heat shield, curtain, window, wall material, eyeglasses, housing for an electric circuit product, or a member used inside an electric circuit product. [8] A sealing material comprising the radio wave shield according to any of [1] to [4]. [9] An adhesive composition containing a cationic group-containing polymer having a cationic group in the polymer chain and water, wherein the content of the cationic group-containing polymer in the adhesive composition is 55% by weight or more and 95% by weight or less, and the content of the water in the adhesive composition is 5% by weight or more and 45% by weight or less.

[10] The adhesive composition according to [9], which is capable of absorbing water in an amount five times or more by weight relative to the weight of the cationic group-containing polymer, thereby making the cationic group-containing polymer swellable in water or soluble in water.

[11] The adhesive composition according to [9] or

[10] , which is curable by polymerization and / or crosslinking.

[12] A molded article obtained by gelling the adhesive composition according to any one of [9] to

[11] .

[13] The molded article according to

[12] , which is capable of absorbing water in an amount five times or more by weight relative to the weight of the cationic group-containing polymer, thereby making the cationic group-containing polymer swellable in water or soluble in water.

[14] A pressure-sensitive adhesive comprising the pressure-sensitive adhesive composition according to any one of [9] to

[11] or the molded article according to

[12] or

[13] .

[15] A composite material obtained by laminating materials via the pressure-sensitive adhesive according to

[14] .

[16] A method for compounding a first material and a second material by polymerizing and / or crosslinking the adhesive composition described in

[11] in contact with the first material and the second material.

[0009] According to the present invention, it is possible to provide a radio wave shielding body having excellent radio wave shielding performance, and a sheet, a partition member, and a sealing material using such a radio wave shielding body. Also, according to the present invention, it is possible to provide a pressure-sensitive adhesive composition that can achieve excellent adhesiveness and strength and is easily peelable after use, and a molded article, a pressure-sensitive adhesive, a composite material, and a composite method using such a pressure-sensitive adhesive composition.

[0010] Fig. 1 is a graph of the return loss and transmission loss in the gigahertz band for Example 3. Fig. 2 is a graph of the absorptance in the gigahertz band for Example 3. Fig. 3 is a graph of the visible light transmittance for Example 4 and Comparative Example 1.

[0011] The radio wave shield of the present invention comprises a cationic group-containing polymer having cationic groups in the polymer chain. The radio wave shield of the present invention has excellent radio wave shielding properties, more specifically, excellent radio wave absorbing or blocking properties. In particular, the present inventors have conducted extensive research to achieve excellent radio wave shielding properties and have found that a cationic group-containing polymer having cationic groups in the polymer chain provides excellent radio wave shielding properties, more specifically, excellent radio wave absorbing properties and / or radio wave blocking properties. Based on this finding, the present invention has been completed.

[0012] Here, conductive carbon materials and magnetic ceramic materials are known as materials that absorb radio waves. Metals are also known as materials that block radio waves. On the other hand, carbon materials, ceramic materials, and metal materials are all opaque, hard, and heavy with a high specific gravity. Therefore, to achieve radio wave absorption or blocking properties using carbon materials, ceramic materials, and metal materials, it is possible to improve the properties by making the radio wave shield an extremely thin layer, fibrous, or fine particles such as powder. However, there are limitations to the degree of improvement and the shape that can be realized. Therefore, flexible, transparent, or lightweight materials are required as radio wave shields.

[0013] Furthermore, in order to improve radio wave shielding performance, a structure called a λ / 4 type may be used. In a λ / 4 type structure, radio wave shielding performance is achieved by the phase difference between incident radio waves and reflected radio waves. For example, JP 2022-165989 A is an example of a polymer material having radio wave shielding properties that utilizes a λ / 4 type structure. According to the technology of JP 2022-165989 A, since it is a technology that utilizes a polymer material, it is thought that it can be lightweight and achieve excellent flexibility. However, when a λ / 4 type structure such as the technology of JP 2022-165989 A is adopted, in order to achieve high radio wave shielding performance, it is necessary to make it into a sheet shape, and there are restrictions on its shape. Furthermore, when a λ / 4 structure is used, absorption is achieved by shifting the phase of the reflected wave by half a wavelength relative to the incident wave, thereby canceling out the reflected wave. This exhibits frequency specificity, resulting in high absorption performance for the target frequency but inability to absorb other frequencies. Furthermore, the structure is basically designed for radio waves incident from a vertical direction, resulting in reduced absorption performance for radio waves incident from oblique directions. In other words, radio wave shields using a λ / 4 structure are unable to achieve radio wave shielding over a wide frequency range or shielding against radio waves from a wide angle. Furthermore, since the wavelengths that can be absorbed by radio wave shields using a λ / 4 structure vary depending on the thickness, variations in thickness during manufacturing can cause variations in absorption performance, making it difficult to obtain radio wave shields that exhibit good shielding performance for desired wavelengths. In particular, when using a λ / 4 structure to achieve absorption characteristics for frequency bands above gigahertz, the radio wave shield must be made several hundred micrometers thick, which exacerbates this problem. Furthermore, scratches or dust contamination during use can cause changes in thickness, resulting in reduced absorption performance. In addition, to achieve a λ / 4 structure, a conductive layer is required, and since a metal foil or the like is used to form the conductive layer, transparency cannot be guaranteed in most cases.

[0014] In response to this, the present inventors have conducted extensive research and have found that a cationic group-containing polymer having cationic groups in the polymer chain allows the polymer itself to exhibit excellent radio wave shielding properties (excellent radio wave absorption properties and / or radio wave blocking properties), that the radio wave shielding performance extends up to the infrared light frequency band corresponding to heat rays, and that the polymer has excellent transmittance in the visible light frequency band. As a result, the polymer has excellent stretchability, flexibility, transparency, and is a lightweight material, and moreover, does not utilize a λ / 4 type structure, so that reduction in radio wave shielding performance due to thickness variation is suppressed. Based on these findings, the present inventors have completed the present invention.

[0015] The radio wave shield of the present invention can control radio waves by absorbing or reflecting them. For example, it can be used to reflect and change the direction of radio waves, block unwanted radio waves, and suppress electromagnetic noise. Specifically, the radio wave shield of the present invention does not utilize radio wave interference, but rather the material itself absorbs radio waves, so that even when radio waves are incident at an oblique angle, the amount of attenuation does not decrease, but rather increases. In addition, the radio wave shield of the present invention contains a cationic group-containing polymer having cationic groups in the polymer chain. Since cationic group-containing polymers have low flammability, even when heat is generated by absorbing radio waves, fires due to heat generation can be suppressed, thereby achieving excellent safety. Furthermore, since the radio wave shield of the present invention contains a cationic group-containing polymer having cationic groups in the polymer chain, it also has excellent light resistance.

[0016] In the present invention, radio waves are a concept that includes electromagnetic waves. ３ Hz to 10 １６ This includes radio waves or electromagnetic waves in the frequency band of 100 Hz. In the present invention, the radio wave shielding body shields or blocks radio waves or electromagnetic waves, and shields or blocks radio waves or electromagnetic waves by reflecting or absorbing radio waves or electromagnetic waves (by attenuating transmission through absorption), or by a combination of these modes.

[0017] The radio wave shield of the present invention can suitably shield radio waves with frequencies of 1 GHz or more and 300 THz or less, more suitably shield radio waves with frequencies of 5.6 GHz or more and 250 THz or less, and even more suitably shield radio waves with frequencies of 10 GHz or more and 200 THz or less.

[0018] The cationic group-containing polymer having a cationic group in the polymer chain used in the present invention (hereinafter referred to as "cationic group-containing polymer" as appropriate) is not particularly limited as long as it is a polymer having a cationic group in the polymer chain, and may be a polymer having a cationic group in the main chain of the polymer, or a polymer having a cationic group in the side chain of the polymer, or further may be a polymer having a cationic group in the main chain and the side chain of the polymer.

[0019] The cationic group contained in the cationic group-containing polymer used in the present invention is not particularly limited, but examples include cationic groups containing a nitrogen atom, a phosphorus atom, a sulfur atom, or an oxygen atom as the central atom. Among these, from the viewpoint of radio wave shielding performance, cationic groups containing a nitrogen atom as the central atom are preferred. Preferred cationic structures are structures (I) or (II) below, and specific examples include ammonium, iminium, imidazolium, and pyridinium. Furthermore, it is preferred that the substituent of the cationic group has two or more groups bonded thereto. Furthermore, the cationic group-containing polymer used in the present invention may have an anionic group in addition to the cationic group in the polymer chain, and may have, for example, a betaine structure.

[0020] The cationic group-containing polymer used in the present invention preferably contains polar atoms other than the cationic groups in addition to the cationic groups. The presence of such polar atoms can neutralize the positive charge of the cations and improve the dissociation of the anions, thereby further improving radio wave shielding performance and also improving transparency and flexibility. Examples of such polar atoms include oxygen atoms and nitrogen atoms. Examples of groups containing such polar atoms include, but are not limited to, ether bonds, ketone groups, carboxyl groups, hydroxyl groups, amine groups, amide bonds, urethane bonds, and urea bonds. Note that the imidazolium structure contains another nitrogen atom in addition to the cationic nitrogen atom in the imidazolium ring, and such another nitrogen atom can also be considered a polar atom other than the cationic group.

[0021] Examples of cationic group-containing polymers include addition polymers of vinyl compounds, polyethers, polyethyleneimines, and polyoxazolines, as cationic group-containing polymers having cationic groups in their side chains. Examples of cationic group-containing polymers having cationic groups in their main chains include ionenes, epichlorohydrin-amine condensates, and polyamidepolyamine epichlorohydrin. These may have any other substituents, or may have some hydrogen atoms substituted with halogen atoms such as fluorine. Furthermore, the cationic group-containing polymer may be a polymer in which, in addition to a structural unit having a cationic group, a structural unit derived from a monomer not having a cationic group is copolymerized, and the pH may be adjusted by introducing a structural unit derived from an acidic monomer or a structural unit derived from a basic monomer.

[0022] The cationic group-containing polymer used in the present invention has a cationic group in the polymer chain. The counter anion for such a cationic group is not particularly limited, and examples thereof include imides such as fluorosulfonylimide, bistrifluoromethylsulfonylimide, and bispentafluoroethylsulfonylimide; halogens such as chlorides and bromides; tetrafluoroboric acid, hexafluorophosphate, dicyanoamide, tetracyanoborate, carbonate, alkylcarbonate, triflate, perchloric acid, nitric acid, sulfuric acid, alkylsulfuric acid, sulfonic acid, phosphoric acid, and alkylphosphate; and the like, but are not particularly limited thereto.

[0023] The cationic group-containing polymer used in the present invention is not particularly limited, but examples of polymers having cationic groups on their side chains include cationic group-containing polyethers (A) containing a repeating unit represented by the following general formula (1):

[0024] (In the above general formula (1), A ＋ represents a nitrogen-containing cationic group. － represents an anion.)

[0025] A ＋ Examples of the nitrogen-containing cationic group represented by the formula (I) include an amino group, a nitrogen-containing cationic aromatic group, and a nitrogen-containing cationic aliphatic group.

[0026] A ＋As the nitrogen-containing cationic aromatic group as the nitrogen-containing cationic aromatic group, a group containing a cationic nitrogen-containing aromatic heterocycle is preferred. The nitrogen-containing aromatic heterocycle in the cationic nitrogen-containing aromatic heterocycle in the group containing a cationic nitrogen-containing aromatic heterocycle may have a nitrogen atom in the ring and have aromaticity, and may have heteroatoms other than nitrogen atoms such as oxygen atoms and sulfur atoms, and some of the atoms constituting the heterocycle may be substituted with substituents. In addition, it may have a polycyclic structure in which two or more rings are condensed. Examples of such nitrogen-containing aromatic heterocyclic structures include five-membered heterocyclic rings such as an imidazole ring, a pyrrole ring, a thiazole ring, an oxazole ring, a pyrazole ring, and an isoxazole ring; six-membered heterocyclic rings such as a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, and a triazine ring; and fused heterocyclic rings such as a quinoline ring, an isoquinoline ring, a quinoxaline ring, a quinazoline ring, a cinnoline ring, a purine ring, an indole ring, an isoindole ring, a benzimidazole ring, a benzoxazole ring, and a benzisoxazole ring. Among these, five-membered and six-membered heterocyclic rings are preferred, and an imidazole ring is more preferred.

[0027] The substituent of the nitrogen-containing aromatic heterocycle is not particularly limited, and examples thereof include alkyl groups, cycloalkyl groups, alkenyl groups such as vinyl groups, aryl groups such as phenyl groups, arylalkyl groups, alkylaryl groups, alkoxyl groups, alkoxyalkyl groups, aryloxy groups, alkanol groups, hydroxyl groups, carbonyl groups, alkoxycarbonyl groups, amino groups, imino groups, nitrile groups, alkylsilyl groups, halogen atoms, etc. The number of carbon atoms in these substituents is preferably 0 to 12, more preferably 1 to 8, and even more preferably 1 to 6.

[0028] A ＋ The nitrogen-containing cationic aliphatic group as may be linear or branched, and may have a non-aromatic ring structure.

[0029] A ＋Specific examples of the nitrogen-containing cationic group represented by the formula (I) include an ammonium group; mono-substituted ammonium groups containing a cationic nitrogen atom, such as a methylammonium group, a butylammonium group, a cyclohexylammonium group, an anilinium group, a benzylammonium group, or an ethanolammonium group; di-substituted ammonium groups containing a cationic nitrogen atom, such as a dimethylammonium group, a diethylammonium group, a dibutylammonium group, or a nonylphenylammonium group; trimethylammonium group, triethylammonium group, n-butyldimethylammonium group, stearyldimethylammonium group, tributylammonium group, trivinylammonium group, triethanolammonium group, N,N-dimethylethanolammonium group, tri(2-ethoxyethyl)ammonium group, and heterocyclic groups containing a cationic nitrogen atom, such as a piperidinium group, a 1-methylpyrrolidinium group, a 1-butylpyrrolidinium group, an imidazolium group, a 1-methylimidazolium group, a 1-ethylimidazolium group, a 1-butyl-imidazolium group, a benzimidazolium group, a pyrrolium group, a 1-methylpyrrolium group, an oxazolium group, a benzoxazolium group, a pyrazolium group, an isoxazolium group, a pyridinium group, a 2,6-dimethylpyridinium group, a pyrazinium group, a pyrimidinium group, a pyridazinium group, a triazinium group, an N,N-dimethylanilinium group, a quinolinium group, an isoquinolinium group, an indolinium group, a quinoxalium group, and an isoquinoxalium group. Among these, a trisubstituted ammonium group containing a cationic nitrogen atom and a heterocyclic group containing a cationic nitrogen atom are preferred.

[0030] In the above general formula (1), X － The anion represented by A ＋ X is a counter anion of a nitrogen-containing cationic group represented by the formula: － For example, the monovalent anion is F － , Cl － ,Br － , I － Halide ions such as (FSO ２ ) ２ N－ , (CF ３ SO ２ ) ２ N － , (CF ３ CF ２ SO ２ ) ２ N － sulfonylimide ions such as CH ３ COO － , C3H7COO － , C.F. ３ COO － , PhCOO － (Ph represents a phenyl group), and other carboxylate ions; CH ３ SO ３ － , C.F. ３ SO ３ － sulfonate ions such as OH － , B.F. ４ － , P.F. ６ － , ClO ４ － , B(CN) ４ － , SCN － , (NC) ２ N － X － The anion may be a polyvalent anion, or may be a polyanion having two or more monovalent anionic groups in the molecule. For example, the polyvalent anion may be a sulfate ion (SO ４ ２－ ) and carbonate ions (CO ３ ２－ For example, examples of polyanions having two or more monovalent anionic groups in the molecule include: － O ３ SCF2CF2CF2SO ３ － , － O ３ SCF2CF2SO ３ － , C.F. ３ SO ２ N － SO ２ CF2CF2OCF2CF2OCF2CF2SO２ N － SO ２ CF ３ Among them, sulfonylimide ions, carboxylate ions, BF ４ － is preferred, and sulfonylimide ion, CH ３ COO － , B.F. ４ － is more preferred.

[0031] In the cationic group-containing polyether (A) used in the present invention, the units represented by the general formula (1) are each independent, and two or more types of units represented by the general formula (1) may be present in the cationic group-containing polyether (A). For example, in the entire repeating units represented by the general formula (1) in the cationic group-containing polyether (A), ＋ All of the nitrogen-containing cationic groups represented by the general formula (1) may be the same kind of nitrogen-containing cationic group, or different kinds of nitrogen-containing cationic groups may be mixed. － All of the anions represented by the formula (I) may be the same kind of anion, or different kinds of anions may be mixed.

[0032] Examples of the repeating unit represented by the above general formula (1) include a repeating unit represented by the following general formula (2): The repeating unit represented by the following general formula (2) is an oxirane unit containing an imidazolium structure. (In the above general formula (2), R １ ~R ４ each independently represents a hydrogen atom or a substituent, R ２ and R ３ may be bonded to each other. － represents an anion.)

[0033] In the above general formula (2), R １ ~R ４R each independently represents a hydrogen atom or a substituent. Examples of the substituent include the same as those described above as the substituent of the nitrogen-containing aromatic heterocycle. １ ~R ４ The substituent as R may be linear or branched, and may have a ring structure. １ ~R ４ The substituent as is preferably linear.

[0034] In the above general formula (2), R １ is not particularly limited as long as it is a hydrogen atom or a substituent, but is preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrocarbon group, even more preferably an alkyl group or an alkenyl group, particularly preferably an alkyl group or a vinyl group, and most preferably an alkyl group. １ The number of carbon atoms in the alkyl group is preferably 0 to 12, more preferably 0 to 8, even more preferably 1 to 6, still more preferably 1 to 4, particularly preferably 1 to 3, and most preferably 1 or 2.

[0035] In the above general formula (2), R ２ ~R ４ are each independently a hydrogen atom or a substituent and are not particularly limited, but are each independently preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom, an alkyl group or a vinyl group, even more preferably a hydrogen atom or an alkyl group, and particularly preferably a hydrogen atom. ２ ~R ４ The number of carbon atoms in each of the groups is preferably 0 to 8, more preferably 0 to 6, even more preferably 0 to 4, still more preferably 0 to 3, particularly preferably 0 to 2, and most preferably 0 to 1.

[0036] In the above general formula (2), R ２ ~R ４ Among R, it is preferable that 1 to 3 represent a hydrogen atom, and more preferable that 2 to 3 represent a hydrogen atom. ２ ~R ４Preferably, 0 to 2 of these represent a substituent such as a hydrocarbon group, and more preferably, 0 to 1 of these represent a substituent such as a hydrocarbon group.

[0037] X in the above general formula (2) － The anion represented by the formula (1) is X － The preferred embodiments are also the same as those of the anion represented by the formula:

[0038] The repeating unit represented by the general formula (2) above preferably contains an imidazolium group, a 1-methylimidazolium group, a 1-butylimidazolium group, a 1-hexylimidazolium group, or a 1-vinylimidazolium group, and more preferably contains a 1-methylimidazolium group.

[0039] The cationic group-containing polyether (A) used in the present invention may contain a repeating unit other than the repeating unit represented by the general formula (1). The repeating unit other than the repeating unit represented by the general formula (1) is not particularly limited as long as it is derived from a monomer copolymerizable with the monomer that gives the repeating unit represented by the general formula (1), and examples thereof include alkylene oxide monomer units such as ethylene oxide units, propylene oxide units, 1,2-butylene oxide units, and 1,2-octylene oxide units; aromatic oxirane monomer units such as styrene oxide units; epihalohydrin monomer units such as epichlorohydrin units, epibromohydrin units, and epiiodohydrin units; alkenyl group-containing oxirane monomer units such as allyl glycidyl ether units; aromatic ether group-containing oxirane monomer units such as phenyl glycidyl ether units; and (meth)acryloyl group-containing oxirane monomer units such as glycidyl acrylate units and glycidyl methacrylate units. Among these, alkylene oxide monomer units, epihalohydrin monomer units, and (meth)acryloyl group-containing oxirane monomer units are preferred, and ethylene oxide units, propylene oxide units, epichlorohydrin units, and glycidyl methacrylate units are more preferred. The cationic group-containing polyether (A) used in the present invention may contain one type of repeating unit other than the repeating unit represented by the general formula (1) alone, or may contain two or more types.

[0040] The cationic group-containing polyether (A) used in the present invention may contain two or more types of repeating units. In this case, the distribution pattern of the multiple repeating units is not particularly limited, but it is preferable that the repeating units have a random distribution.

[0041] The chain structure of the cationic group-containing polyether (A) used in the present invention is not particularly limited, and may be a linear chain structure or a chain structure having branches such as grafts or radial branches.

[0042] The terminal group of the cationic group-containing polyether (A) used in the present invention is not particularly limited and may be any monovalent group. Specific examples of the terminal group include a hydrogen atom, a halogen group, an alkyl group, a haloalkyl group, a hydroxyl group, and an azide group. The terminal group may be a nitrogen-containing cationic group (A) possessed by the repeating unit represented by general formula (1). ＋ ) and anion (X － ) may be a group consisting of

[0043] The content of the repeating units represented by the general formula (1) in the cationic group-containing polyether (A) used in the present invention is not particularly limited, but the average number per molecule is preferably 1 to 100,000, more preferably 3 to 50,000, even more preferably 10 to 30,000, and particularly preferably 30 to 10,000.

[0044] The weight average molecular weight (Mw) of the cationic group-containing polyether (A) used in the present invention is not particularly limited, but is preferably 750 to 2,000,000, more preferably 2,000 to 1,500,000, even more preferably 4,000 to 1,000,000, and particularly preferably 10,000 to 500,000.

[0045] The molecular weight distribution (Mw / Mn) of the cationic group-containing polyether (A) used in the present invention is not particularly limited, but is preferably 1.0 to 4.0, more preferably 1.0 to 2.0, and even more preferably 1.0 to 1.5.

[0046] The weight average molecular weight and molecular weight distribution of the cationic group-containing polyether (A) can be determined by the method described in the Examples below. The molecular weight distribution of the cationic group-containing polyether (A) can be treated as being unchanged from the molecular weight distribution of the base polymer (polyether having no cationic groups) before the introduction of cationic groups.

[0047] The proportion of the repeating units represented by the general formula (1) in the cationic group-containing polyether (A) used in the present invention is not particularly limited, but is preferably 5 to 100 mol %, more preferably 10 to 100 mol %, based on the total repeating units of the cationic group-containing polyether (A).

[0048] The method for synthesizing the cationic group-containing polyether (A) used in the present invention is not particularly limited, and any synthesis method can be used as long as it can produce the target polyether compound. As an example of the synthesis method, first, a base polymer (a polyether having no cationic groups) is obtained by the following method (α) or (β).

[0049] (α) A method for obtaining a base polymer by ring-opening polymerization of a monomer containing an oxirane monomer, which includes at least an epihalohydrin such as epichlorohydrin, epibromohydrin, or epiiodohydrin, in the presence of a catalyst disclosed in JP 2010-53217 A, which catalyst comprises an onium salt of a compound containing an atom of Group 15 or 16 of the periodic table and a trialkylaluminum in which all of the alkyl groups contained are linear alkyl groups.

[0050] (β) A method of obtaining a base polymer by ring-opening polymerization of a monomer containing an oxirane monomer, which includes at least an epihalohydrin such as epichlorohydrin, epibromohydrin, or epiiodohydrin, in the presence of a catalyst prepared by reacting triisobutylaluminum with phosphoric acid and triethylamine, as disclosed in JP-B-46-27534.

[0051] Then, by reacting the halogen groups constituting the epihalohydrin monomer units of the base polymer obtained by the above method (α) or (β) with an onium-converting agent containing a nitrogen-containing cationic group (onium-converting reaction), at least a part of the halogen groups constituting the epihalohydrin monomer units of the base polymer is converted into onium halide groups containing a nitrogen-containing cationic group, thereby forming an anion (X －) is a halide ion. If necessary, the obtained polyether compound containing onium halide structural units can be mixed with an anion (X ) other than a halide ion. － ) with a salt of a metal cation to carry out an anion exchange reaction, thereby converting the halide ion constituting the onium halide group containing the nitrogen-containing cationic group into an anion other than the halide ion (X － ) can be converted to

[0052] The onium-containing agent containing a nitrogen-containing cationic group used in the reaction of the base polymer with the onium-containing agent containing a nitrogen-containing cationic group is a compound represented by the general formula (1) ＋ For example, by using an imidazole compound corresponding to the imidazolium structure in general formula (2) as the onium forming agent, it is possible to form the repeating unit represented by general formula (2).

[0053] The method for reacting the base polymer with the onium-forming agent is not particularly limited, but a method of mixing the base polymer with the onium-forming agent is preferred. The method for mixing the base polymer with the onium-forming agent is also not particularly limited, but examples include a method of adding the onium-forming agent to a solution containing the base polymer and mixing them, a method of adding the base polymer to a solution containing the onium-forming agent and mixing them, and a method of preparing the onium-forming agent and the base polymer as separate solutions and mixing the two solutions.

[0054] In the reaction between the base polymer and the onium-forming agent, an inert solvent is preferably used, and may be either nonpolar or polar. Examples of nonpolar solvents include aromatic hydrocarbons such as benzene and toluene; linear saturated hydrocarbons such as n-pentane and n-hexane; and alicyclic saturated hydrocarbons such as cyclopentane and cyclohexane. Examples of polar solvents include ethers such as tetrahydrofuran, anisole, and diethyl ether; esters such as ethyl acetate and ethyl benzoate; ketones such as acetone, 2-butanone, and acetophenone; aprotic polar solvents such as acetonitrile, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide; and protic polar solvents such as ethanol, methanol, and water. Mixtures of these solvents are also preferably used. The amount of solvent used is not particularly limited, but is preferably used so that the base polymer concentration is 1 to 50% by mass, and more preferably 3 to 40% by mass.

[0055] The amount of onium-forming agent used when reacting the base polymer with the onium-forming agent is not particularly limited and may be determined depending on the content of the repeating unit represented by general formula (1) in the target polyether compound, etc. Specifically, the amount of onium-forming agent used is usually in the range of 0.01 to 100 mol, preferably 0.02 to 50 mol, more preferably 0.03 to 10 mol, and even more preferably 0.05 to 2 mol, per mol of epichlorohydrin units in the base polymer used.

[0056] The pressure when reacting the base polymer with the onium-containing agent is not particularly limited, but is usually 1 to 500 atm, preferably 1 to 100 atm, and particularly preferably 1 to 50 atm. The temperature during the reaction is also not particularly limited, but is usually 0 to 200°C, preferably 20 to 170°C, and more preferably 40 to 150°C. The reaction time is usually 1 minute to 1,000 hours, preferably 3 minutes to 800 hours, more preferably 5 minutes to 500 hours, and even more preferably 30 minutes to 200 hours.

[0057] A polyether compound containing an onium halide structural unit and an anion other than a halide ion (X － The method for carrying out the anion exchange reaction by reacting a salt of a metal cation with a polyether compound containing an onium halide structural unit and an anion other than a halide ion (X － ) and a salt of a metal cation are mixed and reacted.

[0058] The conditions for carrying out the anion exchange reaction are not particularly limited, and include the steps of: reacting a polyether compound containing an onium halide structural unit with an anion other than a halide ion (X － Alternatively, the reaction may be carried out in the presence of other compounds such as an organic solvent. The amount of the salt used is not particularly limited, but is usually 0.01 to 100 mol, preferably 0.02 to 50 mol, and more preferably 0.03 to 10 mol, per mol of onium halide structural units of the onium halide structural unit-containing polyether compound used.

[0059] An anion other than a halide ion (X － The salt of lithium fluoride (Li(FSO2)2N) with a metal cation is not particularly limited, and examples thereof include lithium (bisfluorosulfonyl)imide (Li(FSO2)2N), lithium bis(trifluoromethylsulfonyl)imide (Li(CF3SO2)2N), lithium (bispentafluoroethylsulfonyl)imide (Li(CF3CF2SO2)2N), sodium acetate (CH3COONa), silver acetate (CH3COOAg), lithium butyrate (C3H7COOLi), lithium trifluoroacetate (CF3COOLi), lithium benzoate (PhCOOLi), potassium tetracyanoborate (KB(CN) ４ ), lithium thiocyanate (LiSCN), lithium (biscyano)imide (Li(NC) ２N), lithium methylsulfonate (LiCH3SO3), lithium trifluoromethylsulfonate (LiCF3SO3), potassium hydroxide (KOH), lithium perchlorate (LiClO4), etc. In the case of salts of polyvalent anions and metal cations, silver sulfate (Ag ２ SO ４ ２－ ), sodium carbonate (Na ２ CO ３ ２－ For example, examples of salts of polyanions having two or more monovalent anionic groups in the molecule and metal cations include LiO ３ SCF2CF2CF2SO ３ Li, LiO ３ SCF2CF2SO ３ Li, Li ２ (CF ３ SO ２ NSO ２ CF2CF2OCF2CF2OCF2CF2SO ２ NSO ２ CF ３ ), among others.

[0060] The pressure during the anion exchange reaction is usually 1 to 500 atm, preferably 1 to 100 atm, and particularly preferably 1 to 50 atm. The reaction temperature is usually −30 to 200° C., preferably −15 to 180° C., and more preferably 0 to 150° C. The reaction time is usually 1 minute to 1,000 hours, preferably 3 minutes to 100 hours, more preferably 5 minutes to 10 hours, and even more preferably 5 minutes to 3 hours.

[0061] After the anion exchange reaction is completed, metal cations, halide ions, and salts thereof can be removed by washing with water or membrane separation using a semipermeable membrane, and the mixture containing the cationic group-containing polyether (A) can be recovered. Alternatively, the mixture containing the cationic group-containing polyether (A) can be recovered by extracting the cationic group-containing polyether (A) using a solvent such as methanol. Furthermore, the desired cationic group-containing polyether (A) can be recovered by a conventional method, such as drying under reduced pressure.

[0062] Further, the cationic group-containing polymer used in the present invention also includes a side-chain ammonium group-containing polymer (B) containing a repeating unit represented by the following general formula (3), which is a polymer having a cationic group on the side chain of the polymer. (In the above general formula (3), Z is a divalent linking group, and R ５ ~R ７ each independently represents a hydrogen atom or a substituent, R ５ ~R ７ may be bonded to each other. － represents an anion.)

[0063] Z is a divalent linking group, and is preferably an alkylene group which may contain a heteroatom. Examples of heteroatoms include an oxygen atom, a nitrogen atom, and a sulfur atom. Examples of groups containing a heteroatom include an amide group (-CO-NH-), an ester group (-COO-), an ether group (-O-), and a thioether group (-S-). Among these, Z is preferably an alkylene group containing an amide group, such as -CO-NH-(CH ２ ) ｐ A group represented by - (where p is an integer of 1 to 5, and preferably n=3) is more preferred.

[0064] R ５ ~R ７ are each independently a hydrogen atom or a substituent and are not particularly limited, but are each independently preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom, an alkyl group or a vinyl group, even more preferably a hydrogen atom or an alkyl group, and particularly preferably an alkyl group. ５ ~R ７ The number of carbon atoms in each of the groups is preferably 1 to 8, more preferably 1 to 3, even more preferably 1 to 4, and particularly preferably 1. In other words, it is preferably a methyl group.

[0065] In the above general formula (3), X － The anion represented by the formula (1) is not particularly limited, but examples thereof include the same anions as those represented by the formula (1) above.

[0066] The side-chain ammonium group-containing polymer (B) may also contain a repeating unit other than the repeating unit represented by general formula (3). The repeating unit other than the repeating unit represented by general formula (3) is not particularly limited as long as it is derived from a monomer copolymerizable with the monomer that gives the repeating unit represented by general formula (3), and examples thereof include units derived from unsaturated carboxylic acids and salts thereof such as acrylic acid and methacrylic acid, unsaturated carboxylic acid esters such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, and methoxyethoxyethoxyethyl acrylate, acrylamide, substituted acrylamide, styrene, vinylpyridine, and vinylpyrrolidone.

[0067] In the side-chain ammonium group-containing polymer (B) used in the present invention, the units represented by the above general formula (3) are each independent, and two or more types of units represented by the general formula (3) may be present in the side-chain ammonium group-containing polymer (B). When the side-chain ammonium group-containing polymer (B) used in the present invention contains two or more types of repeating units, the distribution pattern of the multiple repeating units is not particularly limited, but it is preferable that they have a random distribution.

[0068] Specific examples of the side chain ammonium group-containing polymer (B) used in the present invention include poly{[3-(methacryloylamino)propyl]trimethylammonium chloride}, poly[(3-acrylamidopropyl)trimethylammonium chloride], poly{[2-(methacryloyloxy)ethyl]trimethylammonium chloride}, poly{[2-(acryloyloxy)ethyl]trimethylammonium chloride}, poly[2-dimethylaminoethyl methacrylate ethyl sulfate], poly[vinylbenzyltrimethylammonium chloride], poly[N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride], poly[2-methacryloyloxyethyl phosphorylcholine], poly[2-(N-3-sulfopropyl-N,N-dimethylammonium)ethyl methacrylate], and the like. Among these, poly[(3-acrylamidopropyl)trimethylammonium chloride] is preferred.

[0069] The weight average molecular weight (Mw) of the side chain ammonium group-containing polymer (B) used in the present invention is not particularly limited, but is preferably 750 to 2,000,000, more preferably 1,000 to 1,500,000, even more preferably 2,000 to 1,000,000, and particularly preferably 4,000 to 500,000. The weight average molecular weight of the side chain ammonium group-containing polymer (B) can be determined using GPC in terms of standard polystyrene.

[0070] Further, the cationic group-containing polymer used in the present invention also includes a polymer (C) having a side chain cyclic ammonium group, which is a polymer having a cationic group on its side chain and which contains a repeating unit represented by the following general formula (4-1) or the following general formula (4-2): (In the above general formula (4-1) and general formula (4-2), R ８ , R ９ each independently represents a hydrogen atom or a substituent, R ８ , R ９ In addition, in the general formula (4-1) and the general formula (4-2), X － represents an anion.)

[0071] R ８ , R ９ are each independently a hydrogen atom or a substituent and are not particularly limited, but are each independently preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom, an alkyl group or a vinyl group, even more preferably a hydrogen atom or an alkyl group, and particularly preferably an alkyl group. ８ , R ９ The number of carbon atoms in each of the groups is preferably 1 to 8, more preferably 1 to 3, even more preferably 1 to 4, and particularly preferably 1. In other words, it is preferably a methyl group.

[0072] In the above general formula (4-1) and general formula (4-2), X － The anion represented by the formula (1) is not particularly limited, but examples thereof include the same anions as those represented by the formula (1) above.

[0073] The side chain cyclic ammonium group-containing polymer (C) may also contain a repeating unit other than the repeating units represented by general formula (4-1) or (4-2). The repeating unit other than the repeating unit represented by general formula (4) may be a unit derived from a monomer copolymerizable with the monomer that gives the repeating unit represented by general formula (4-1) or (4-2), and is not particularly limited. Examples of such a monomer include N-vinylpyrrolidone, acrylamide, (meth)acrylic acid, (meth)acrylate salts, and (meth)acrylates having an ethylene oxide unit.

[0074] In the side chain cyclic ammonium group-containing polymer (C) used in the present invention, the units represented by the above general formula (4) are each independent, and two or more types of units represented by the general formula (4) may be present in the side chain cyclic ammonium group-containing polymer (C). When the side chain cyclic ammonium group-containing polymer (C) used in the present invention contains two or more types of repeating units, the distribution pattern of the multiple repeating units is not particularly limited, but it is preferable that they have a random distribution.

[0075] A specific example of the polymer (C) containing a cyclic ammonium group in a side chain used in the present invention is preferably poly(diallyldimethylammonium chloride).

[0076] The weight average molecular weight (Mw) of the side chain cyclic ammonium group-containing polymer (C) used in the present invention is not particularly limited, but is preferably 750 to 2,000,000, more preferably 2,000 to 1,500,000, even more preferably 4,000 to 1,000,000, and particularly preferably 10,000 to 500,000. The weight average molecular weight of the side chain cyclic ammonium group-containing polymer (C) can be determined using GPC in terms of standard polystyrene.

[0077] Further, the cationic group-containing polymer used in the present invention includes a main chain ammonium group-containing polymer (D) containing a repeating unit represented by the following general formula (5), which is a polymer having a cationic group in the main chain of the polymer. (In the above general formula (5), R １０ , R １１ each independently represents a hydrogen atom or a substituent, R １０ , R １１ may be bonded to each other. － represents an anion.)

[0078] R １０ , R １１ are each independently a hydrogen atom or a substituent and are not particularly limited, but are each independently preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom, an alkyl group or a vinyl group, even more preferably a hydrogen atom or an alkyl group, and particularly preferably an alkyl group. １０ , R １１ The number of carbon atoms in each of the groups is preferably 1 to 8, more preferably 1 to 3, even more preferably 1 to 4, and particularly preferably 1. In other words, it is preferably a methyl group.

[0079] In the above general formula (5), X －The anion represented by the formula (1) is not particularly limited, but examples thereof include the same anions as those represented by the formula (1) above.

[0080] The main chain ammonium group-containing polymer (D) can be obtained by reacting a secondary amine with epihalohydrin to form the repeating unit represented by general formula (5).

[0081] Secondary amines are compounds in which two hydrocarbon groups and one hydrogen atom are bonded to one nitrogen atom, and compounds in which a nitrogen atom is bonded to one hydrogen atom in a heterocycle. Examples of such secondary amines include aliphatic secondary amines, aromatic secondary amines, alicyclic secondary amines, and heterocyclic secondary amines, and two or more of these may be used in combination.

[0082] Examples of the aliphatic secondary amine include dimethylamine, diethylamine, diisopropylamine, dibutylamine, methylethylamine, methylpropylamine, methylbutylamine, methyloctylamine, methyllaurylamine, and dibenzylamine.

[0083] Examples of aromatic secondary amines include N-alkylanilines such as N-methylaniline, N-ethylaniline, N-propylaniline, N-butylaniline, N-pentylaniline, N-hexylaniline, N-octylaniline, N-decylaniline, N-laurylaniline, and N-benzylaniline; N-methyltoluidine, N-ethyltoluidine, N-propyltoluidine, N-butyltoluidine, N-pentyltoluidine, N-hexyltoluidine, and N-octyltoluidine; toluidine, N-decyl toluidine, N-lauryl toluidine, N-benzyl toluidine, and other N-alkyl toluidines; N-methyl naphthylamine, N-ethyl naphthylamine, N-propyl naphthylamine, N-butyl naphthylamine, N-pentyl naphthylamine, N-hexyl naphthylamine, N-octyl naphthylamine, N-decyl naphthylamine, N-lauryl naphthylamine, N-benzyl naphthylamine, and other N-alkyl naphthylamines; and the like.

[0084] Examples of alicyclic secondary amines include N-alkylcyclohexylamines such as N-methylcyclohexylamine, N-ethylcyclohexylamine, N-propylcyclohexylamine, N-butylcyclohexylamine, N-hexylcyclohexylamine, N-octylcyclohexylamine, N-decylcyclohexylamine, and N-laurylcyclohexylamine; N-alkylcyclooctylamines such as N-methylcyclooctylamine, N-ethylcyclooctylamine, N-propylcyclooctylamine, N-butylcyclooctylamine, N-hexylcyclooctylamine, N-octylcyclooctylamine, N-decylcyclooctylamine, and N-laurylcyclooctylamine; and dicycloalkylamines such as dicyclohexylamine and dicyclooctylamine.

[0085] Examples of the heterocyclic secondary amine include piperidine, pyrrolidine, 2-methylpiperidine, and 4-methylpiperidine.

[0086] As the secondary amine, an aliphatic secondary amine is preferred, and dimethylamine and diethylamine are preferred, with dimethylamine being particularly preferred.

[0087] Examples of epihalohydrins include epichlorohydrin, epibromohydrin, methylepichlorohydrin, methylepibromohydrin, etc. Among these, epichlorohydrin is particularly preferred.

[0088] The main chain ammonium group-containing polymer (D) may also be one obtained by reacting an amine other than a secondary amine with a secondary amine and an epihalohydrin. Examples of the amine other than a secondary amine include compounds having two or more amino groups, such as ethylenediamine, propylenediamine, diethylenetriamine, hexylenediamine, triethylenetetramine, tetraethylenepentamine, isophoronediamine, piperazine, diphenylmethanediamine, hydrazine, and hydrazides such as adipic acid dihydrazide. Among these, ethylenediamine is preferably used.

[0089] The main chain ammonium group-containing polymer (D) can be produced, for example, by mixing and stirring a secondary amine, an epihalohydrin, and, if necessary, an amine other than the secondary amine, under heating conditions, and then subjecting the mixture to addition polymerization by a known, commonly used method.

[0090] The weight average molecular weight (Mw) of the main chain ammonium group-containing polymer (D) used in the present invention is not particularly limited, but is preferably 750 to 2,000,000, more preferably 2,000 to 1,500,000, even more preferably 4,000 to 1,000,000, and particularly preferably 10,000 to 500,000. The weight average molecular weight of the main chain ammonium group-containing polymer (D) can be determined using GPC in terms of standard polystyrene.

[0091] The radio wave shield of the present invention contains a cationic group-containing polymer such as the above-mentioned cationic group-containing polyether (A), side-chain ammonium group-containing polymer (B), side-chain cyclic ammonium group-containing polymer (C), and main-chain ammonium group-containing polymer (D). As mentioned above, the cationic group-containing polymer is not limited to these polymers, and is not particularly limited as long as it has a cationic group in the polymer chain.

[0092] The radio wave shield of the present invention may be a crosslinked body (three-dimensionally crosslinked body) obtained by crosslinking (three-dimensionally crosslinking) a cationic group-containing polymer, or may be a crosslinked body (three-dimensionally crosslinked body) obtained by allowing a crosslinkable polymer capable of forming a crosslinked structure to coexist with the cationic group-containing polymer and crosslinking (three-dimensionally crosslinking) such a crosslinkable polymer. Examples of crosslinking methods include ultraviolet irradiation, visible light irradiation, heating, electron beam irradiation, and radiation irradiation. Urethane reaction, epoxy reaction, oxazoline group reaction, dimerization reaction of cinnamic acid, etc., and azetidinium ring reaction can also be used.

[0093] In the radio wave shield of the present invention, the cationic group-containing polymer itself exhibits radio wave shielding properties. The content of the cationic group-containing polymer in the radio wave shield of the present invention is not particularly limited and may be appropriately selected depending on the application and purpose. However, the radio wave shield of the present invention preferably contains the cationic group-containing polymer in a proportion of 1 to 100% by weight, preferably 3 to 100% by weight, more preferably 5 to 100% by weight, even more preferably 10 to 100% by weight, even more preferably 30 to 100% by weight, and particularly preferably 50 to 100% by weight. If the content of the cationic group-containing polymer is too low, sufficient radio wave shielding properties may not be obtained. For example, cationic group-containing polymers are sometimes used as wet strength agents in sludge sedimentation treatment and the papermaking industry. However, the content of cationic group-containing polymer in sludge is approximately less than 1%, and the content of cationic group-containing polymer in paper is approximately 0.1%, both of which are very low. In such cases, the radio wave shielding properties may not be sufficient.

[0094] The radio wave shield of the present invention may be a composition containing a cationic group-containing polymer and water, and such a configuration can provide excellent adhesive properties. In this case, the content of the cationic group-containing polymer is preferably 55% by weight or more, more preferably 60% by weight or more, and even more preferably 65% ​​by weight or more, from the viewpoint of self-standing strength, and is preferably less than 100% by weight, more preferably 95% by weight or less, and even more preferably 90% by weight or less, from the viewpoint of adhesive properties. The content of water is preferably more than 1% by weight, more preferably 5% by weight or more, even more preferably 10% by weight or more, and preferably 45% by weight or less, more preferably 40% by weight or less, and even more preferably 35% by weight or less.

[0095] In the radio wave shield of the present invention, the cationic group-containing polymer preferably has dissociated ions, and the dissociated ions provide high flexibility, which makes it easy to process and less susceptible to breakage. The dissociation of ions can be determined by ionic conductivity using an AC impedance method. －１０ ~10 －９ If ionic conductivity is observed on the order of about S / cm, it can be determined that ions are dissociated. If ionic dissociation is insufficient, a solvent may be added to promote ionic dissociation. Examples of the solvent include water, organic solvents, oils, and ionic liquids. As the organic solvent, alcohols, particularly polyhydric alcohols, and as the oil, modified silicone oils, particularly silicone oils modified with ethylene oxide chains, are preferred from the viewpoint of compatibility.

[0096] The shape of the radio wave shield of the present invention is not particularly limited, but is preferably, for example, sheet-like or plate-like. In this case, the radio wave shield formed into a sheet or plate-like shape may be used as a single layer, or multiple layers may be stacked. Using multiple layers can increase the number of reflections, thereby adjusting the radio wave shielding performance. When multiple layers are stacked, the radio wave shields of the present invention may be stacked on top of each other, or two or more radio wave shields of the present invention may be sandwiched between sheets or plates different from the radio wave shields of the present invention. The radio wave shielding material may be a graded material whose composition changes stepwise. The radio wave shield of the present invention can also be used as a bulk body (= mass), and may be shaped as desired like clay or used to fill gaps like putty. Furthermore, the radio wave shield of the present invention may be a foam.

[0097] For example, when the radio wave shield of the present invention is formed into a sheet or plate shape, the forming method is not particularly limited, but when the cationic group-containing polymer constituting the radio wave shield of the present invention is in a liquid state at room temperature, it may be held by a sheet-like or plate-like support to form a sheet or plate, for example, by sandwiching it between a pair of supports.

[0098] Alternatively, when the radio wave shielding material of the present invention is to be made into a sheet, plate, or bulk body, it may be injected into the desired location in the form of a fluid monomer and polymerized in situ to form a sheet, plate, or bulk body. When the radio wave shielding material of the present invention is to be made into a crosslinked body formed by crosslinking a cationic group-containing polymer, or when it is to be made into a crosslinked body formed by coexisting a crosslinkable polymer capable of forming a crosslinked structure and crosslinking this, it may be injected into the desired location in the form of a fluid monomer or polymer and polymerized in situ to form a sheet, plate, or bulk body.

[0099] Furthermore, when the radio wave shield of the present invention is in the form of a sheet or plate, the surface of the sheet or plate radio wave shield may be roughened or grooves may be cut into the surface for the purpose of scattering radio waves on the sheet or plate surface. In this case, since visible light also tends to be scattered, from the perspective of ensuring visibility, a surface material (for example, a surface material made from methyl methacrylate) may be provided that conforms to the roughened or grooved surface, so that the surface material covers the irregularities of the roughened or grooved surface of the radio wave shield of the present invention, while the surface of the surface material makes the physical surface smooth.

[0100] Furthermore, the radio wave shield of the present invention preferably has an exterior. For example, when the radio wave shield of the present invention is in the form of a sheet or plate, it is preferable to use a pair of sheet- or plate-shaped exteriors as the exterior, and to sandwich the radio wave shield between the pair of exteriors. By having an exterior, it is possible to increase the return loss and reduce reflected radio waves.

[0101] The exterior is preferably made of an organic material such as plastic or rubber, or an inorganic material such as glass or ceramic. The outermost layer of the exterior is preferably water-repellent. Water repellency can be determined by dripping water onto the surface of the exterior and observing whether or not the water penetrates into the interior. Alternatively, if the method of dripping water is unable to determine whether or not the water penetrates, the exterior can be immersed in water and the weight increase determined by whether or not the rate of weight increase is 1% by weight or less.

[0102] From the viewpoints of dimensional stability and low flammability, it is preferable to use inorganic materials such as glass and ceramics for the exterior. Furthermore, from the viewpoint of the resistance of the radio wave shield to breakage, it is preferable to use organic materials. In particular, from the viewpoint of the degree of freedom in shape, it is preferable to use resin materials. From the viewpoint of the degree of freedom in shape and the degree of freedom in deformation of the radio wave shield, it is preferable to use rubber materials. Among resin materials, from the viewpoint of low flammability, chlorinated resins such as vinyl chloride resin and chlorinated polyvinyl chloride, polyimide resins, fluororesins, and polycarbonate resins are preferable. Among rubber materials, from the viewpoint of low flammability, silicone rubbers, fluororubbers, and urethane rubbers are preferable.

[0103] Furthermore, since scratches on the surface of the radio wave shielding body can affect the radio wave absorption performance, it is preferable that the pencil hardness of the outermost layer of the exterior be H or higher, which makes it easier to maintain the radio wave absorption performance over a long period of time. The pencil hardness of the outermost layer of the exterior is more preferably 2H or higher, even more preferably 3H or higher, and even more preferably 4H or higher. Furthermore, the coverage of the exterior is preferably 30% or higher, more preferably 40% or higher, and even more preferably 50% or higher of the entire radio wave shielding body, with the upper limit being preferably 100% or lower, more preferably 95% or lower, and even more preferably 90% or lower.

[0104] Furthermore, since the radio wave shield of the present invention contains a cationic group-containing polymer and is flexible, this flexibility can be utilized to apply it to a variety of uses, and it may also be reinforced by various methods when in use.

[0105] Examples of a reinforcing method include integrating the shield with a surface material such as a plastic plate, plastic film, hard coat, rubber plate, rubber film, glass plate, glass film, or metal foil. The surface material preferably has a pencil hardness of B or higher. The shield may also be reinforced by placing a frame around the radio wave shield of the present invention, and examples of the frame material include metal, wood, plastic, and glass.

[0106] Examples of reinforcing methods include integrating a sheet-shaped, plate-shaped, or bulk-shaped radio wave shield with a fiber material, and mixing a fiber material with a cationic group-containing polymer to form a radio wave shield. Examples of fiber materials include glass fiber, natural fiber, synthetic fiber, carbon fiber, carbon nanotube, ceramic fiber, and PTFE, and millifiber, microfiber, and nanofiber can be used without limitation. The fiber material may be a single fiber, a twisted yarn, or a coil, and may be a woven fabric or a nonwoven fabric.

[0107] Further, as a reinforcing method, a method of mixing a filler with a cationic group-containing polymer to produce a radio wave shielding body can be mentioned. Examples of fillers include particulate fillers, whiskers, fibrous substances, conductive substances, magnetic substances, metals, carbon materials, ceramics, nanofibers, microfibers, dyes, pigments, foaming agents, hollow particles, etc., and the particle size of these is not particularly limited. In particular, when the radio wave shielding body is to maintain transparency, it is preferable to use a transparent filler, and it is desirable to match the refractive index of the cationic group-containing polymer with that of the filler. Examples of transparent fillers include resin powder and glass powder.

[0108] Another reinforcing method is to mix another polymer with the cationic group-containing polymer to form a radio wave shield. Examples of the other polymer include various neutral polymers and various anionic polymers. As described above, a crosslinkable polymer capable of forming a crosslinked structure may also be used.

[0109] When the radio wave shield of the present invention is in the form of a sheet or plate, the thickness is preferably 10 μm to 3 cm, more preferably 50 μm to 2 cm, and even more preferably 100 μm to 1.5 cm. Furthermore, when the radio wave shield of the present invention is in the form of a sheet or plate, the basis weight of the cationic group-containing polymer in the thickest part is preferably 100 μg / cm from the viewpoint of sufficiently enhancing the radio wave shielding performance. ２ It is preferable that the concentration is 500 μg / cm or more. ２ More preferably, it is 1000 μg / cm or more. ２ It is more preferable that the density is 5 g / cm or more, and although the conditions are not particularly limited, it is preferably 5 g / cm ２ The following is the result.

[0110] From the viewpoint of flexibility, the radio wave shield of the present invention preferably has a Duro-A hardness of HDA 60 or less, more preferably HDA 55 or less, even more preferably HDA 50 or less, and even more preferably HDA 45 or less. By having a Duro-A hardness within the above range, when the radio wave shield is joined to another member, any air bubbles that may have entered the joining interface are more likely to disappear.

[0111] The radio wave shielding material of the present invention contains a cationic group-containing polymer, which itself has excellent radio wave shielding performance, but may also contain other radio wave absorbing materials for the purpose of further improving or adjusting the radio wave shielding performance. Examples of other radio wave absorbing materials include carbon materials such as graphite, metals, conductive polymers, conductive ceramics, and magnetic materials.

[0112] Furthermore, the radio wave shield of the present invention may be provided with a conductive layer. The conductive layer may be formed, for example, from ITO, PEDOT, copper, silver, or gold. The conductive layer may be solid or intermittent, and examples thereof include striped, mesh, and repeating patterns. A λ / 4 structure may be realized by utilizing the conductive layer. By appropriately patterning the conductive layer, the amount and angle of reflection and refraction of electromagnetic waves can also be controlled.

[0113] The radio wave shield of the present invention can be made into a sheet or plate shape and used in the form of, for example, a partition, a screen, a wall material (wall, wallpaper), a humidity control material, a moisture collector, a moisture release material, a heat shield, a curtain, a window, an apron, a hat, glasses, clothing, a coat, etc.

[0114] When the radio wave shield of the present invention is used as a humidity conditioner, it is preferable to use a breathable exterior material, and nonwoven fabrics, porous membranes, etc. are preferred. Examples of materials include plastics, paper, metals, and ceramics. From the viewpoint of allowing water vapor to pass through while preventing water penetration, it is preferable that the pore size of the nonwoven fabric or porous membrane be small, and the pore size is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 10 μm or less. Furthermore, from the viewpoint of water repellency, fluorine-based polymers and hydrocarbon-based polymers are suitable.

[0115] Furthermore, when the radio wave shield of the present invention is used as a curtain, it is preferable to use a material with high flexibility and low flammability as the exterior, and specific examples include vinyl chloride resin, vinylidene chloride resin, chlorinated polyvinyl chloride, silicone rubber, urethane, polycarbonate, etc.

[0116] Alternatively, the radio wave shield of the present invention can be made into a bulk body (=mass) and placed indoors as a decorative item to absorb radio waves, or it can be placed near an electric circuit, as a housing for an electric circuit product, or in a predetermined space inside the case of an electronic device to absorb unnecessary radio waves.The radio wave shield of the present invention can also be used as a sealing material for various electric and electronic parts.

[0117] Furthermore, the radio wave shield of the present invention may be used with another radio wave reflector disposed on the outside, thereby increasing the design freedom for reflection and absorption. Specific examples of the other radio wave reflector include a metal plate, a carbon-containing plate, a metal mesh, and glass or plastic with a conductive layer. In this case, the angle of the radio wave shield of the present invention and the other radio wave reflector can be made variable manually or automatically, thereby further increasing the design freedom for reflection and absorption. Furthermore, since the radio wave shield of the present invention has excellent stretchability and flexibility, it can be manually or automatically bent to a desired curvature when used.

[0118] The adhesive composition of the present invention is an adhesive composition containing a cationic group-containing polymer having a cationic group in the polymer chain and water, wherein the content of the cationic group-containing polymer in the adhesive composition is 55% by weight or more and 95% by weight or less, and the content of the water in the adhesive composition is 5% by weight or more and 45% by weight or less.

[0119] The pressure-sensitive adhesive composition of the present invention contains a cationic group-containing polymer having a cationic group in the polymer chain and water in the above-mentioned specific ranges, thereby achieving excellent adhesive properties and strength and enabling easy peeling after use.

[0120] Here, acrylic adhesives, SIS adhesives, polyvinyl butyral, etc. are well known as pressure-sensitive adhesives and adhesives. However, although these provide good adhesion and function well during use, they are difficult to disassemble after use or require many steps for disassembly. Therefore, there has been a demand for a pressure-sensitive adhesive that can be easily separated after use while achieving sufficient bonding strength. In contrast, the pressure-sensitive adhesive composition of the present invention can achieve excellent pressure-sensitive adhesiveness and strength, and can also be easily peeled after use, more specifically, can be easily peeled using water.

[0121] In particular, composite materials such as laminated glass are difficult to disassemble into their original components, making them difficult to recycle. In contrast, when adhesives and pressure-sensitive adhesives such as the acrylic pressure-sensitive adhesives, SIS pressure-sensitive adhesives, and polyvinyl butyral are physically removed, the substrate is destroyed or the adhesive remains, making clean removal difficult. While the use of organic solvents is conceivable for removing acrylic pressure-sensitive adhesives, these methods are undesirable in terms of the working environment due to their flammability and adverse effects on the human body. Furthermore, organic solvents and hydrofluoric acid are used to remove polyvinyl butyral used in laminated glass for automobiles, which are also undesirable. In particular, when the substrate to be combined is an organic material such as plastic, the removal procedure using organic solvents may damage the substrate. In contrast, the pressure-sensitive adhesive composition of the present invention can achieve excellent adhesiveness and strength, and can be easily removed after use, effectively solving these problems and making it suitable for such applications. It is also preferred to use the composition in combination with a polyvinyl butyral layer.

[0122] In addition, although the above-mentioned pressure-sensitive adhesives and adhesives such as polyvinyl butyral can strengthen the bond between the substrate materials, they have the problem that once peeling occurs for some reason, they do not re-adhere. In contrast, the pressure-sensitive adhesive composition of the present invention has sufficient bonding strength when used, and even if unintentional peeling occurs, it will re-adhere upon re-contact, so it has the advantage that the bond is not easily lost in applications where repeated deformation or vibration occurs.

[0123] Since the adhesive composition of the present invention contains a cationic group-containing polymer having cationic groups in the polymer chain, it also has excellent radio wave absorption properties. Therefore, in addition to the method using water, it can also be easily peeled in a short time by, for example, irradiating microwaves (2.45 GHz) from a microwave oven or the like to generate high-temperature steam and spread the interface. The adhesive composition of the present invention can also be suitably used as a sticker to be attached to items that are easily damaged by peeling force, such as clothing and furniture. It can be peeled off without damaging the clothing or furniture by wetting it with water, rather than by mechanical peeling. In this case, it is also preferable to provide a waterproof layer on the edge when using it before peeling.

[0124] Examples of adhesives that can be peeled off with water include classic glues made from natural water-soluble polymers. However, glues made from such natural water-soluble polymers achieve their adhesive properties by hardening during adhesion, and because they lack elasticity and flexibility, they have the problem of peeling off when subjected to mechanical strain. Furthermore, although a peeled glue can be reapplied by wetting it with water, it is difficult to achieve a clean finish. Furthermore, while it is possible to keep natural water-soluble polymers wet for long periods of time, because they are naturally derived, there are problems with mold and bacteria growing, which can lead to poor appearance, and there is also the problem of the water-soluble polymer itself decomposing.

[0125] The cationic group-containing polymer having a cationic group in the polymer chain to be contained in the pressure-sensitive adhesive composition of the present invention is not particularly limited as long as it is a polymer having a cationic group in the polymer chain, and may be a polymer having a cationic group in the main chain of the polymer, or a polymer having a cationic group in the side chain of the polymer, or even a polymer having a cationic group in the main chain and the side chain of the polymer. According to the present invention, the cationic group of the cationic group-containing polymer can achieve excellent adhesiveness. As such a cationic group-containing polymer, the same one as the radio wave shield described above can be used in the same manner.

[0126] Furthermore, from the viewpoint of shape retention during adhesive bonding, it is preferable to make the adhesive composition of the present invention curable by polymerizing and / or crosslinking the cationic group-containing polymer. Examples of polymerization and / or crosslinking methods include ultraviolet irradiation, visible light irradiation, heating, electron beam irradiation, and radiation irradiation. Urethane reaction, epoxy reaction, reaction of oxazoline groups, dimerization reaction of cinnamic acid, and reaction of azetidinium rings can also be used. Polymerization and / or crosslinking can gel the adhesive composition of the present invention, thereby forming a gelled molded article. The shape of the molded article is not particularly limited, and can be any shape suitable for adhesive bonding. For example, a sheet-like molded article or a layer-like molded article can be used. Alternatively, when a polymerizable composition is used that can be cured by polymerization and / or crosslinking to form a gel, a method of polymerizing and / or crosslinking the cationic group-containing polymer itself or a method of polymerizing and / or crosslinking by adding another polymer or a polyfunctional monomer may be used.

[0127] From the viewpoints of flexibility and adhesiveness, a molded article obtained using the pressure-sensitive adhesive composition of the present invention preferably has a Duro-A hardness of HDA 50 or less, more preferably HDA 45 or less, even more preferably HDA 40 or less, and even more preferably HDA 35 or less. When the Duro-A hardness is within the above range, any air bubbles that enter the bonding interface when bonding adherends are more likely to disappear.

[0128] Alternatively, when the pressure-sensitive adhesive composition of the present invention is not polymerized or crosslinked, from the viewpoint of ensuring sufficient shape retention, it is preferable to use a cationic group-containing polymer having a weight-average molecular weight of 100,000 or more, more preferably 200,000 or more, and even more preferably 300,000 or more.

[0129] The content of the cationic group-containing polymer in the pressure-sensitive adhesive composition of the present invention is 55% by weight or more and 95% by weight or less, preferably 60% by weight or more and 90% by weight or less, more preferably 65% ​​by weight or more and 85% by weight or less. The content of water in the pressure-sensitive adhesive composition of the present invention is 5% by weight or more and 45% by weight or less, preferably 10% by weight or more and 40% by weight or less, more preferably 15% by weight or more and 35% by weight or less. If the content of the cationic group-containing polymer is too low, the strength will be insufficient, and if the content of water is too low, the adhesive properties will be insufficient. The content ratios of the cationic group-containing polymer and water may be within the above ranges in the usage environment, but are preferably within the above ranges at least in an environment of 25°C and 50% RH. Taking their hygroscopic properties into account, it is desirable to measure the content of the cationic group-containing polymer and water after leaving them for a long period of time (e.g., about one week) until the condition stabilizes.

[0130] The adhesive composition of the present invention may contain components other than the cationic group-containing polymer and water, and may contain salts such as sodium chloride and potassium chloride. The inclusion of salts can improve ionic conductivity and corrosion resistance. Furthermore, the adhesive composition of the present invention may contain a surfactant, an anionic polymer, an amphoteric polymer, etc., and may have its pH adjusted by adjusting the type of monomer used or by using a buffer.

[0131] Furthermore, the pressure-sensitive adhesive composition of the present invention may be reinforced with a fiber material. Examples of the fiber material include glass fiber, natural fiber, synthetic fiber, carbon fiber, carbon nanotube, ceramic fiber, PTFE, etc., and millifiber, microfiber, nanofiber, etc. can be used without limitation. Furthermore, the fiber material may be a single fiber, a twisted yarn, a coiled shape, a woven fabric, or a nonwoven fabric.

[0132] The pressure-sensitive adhesive composition of the present invention can be suitably used as a pressure-sensitive adhesive. In this case, the pressure-sensitive adhesive composition of the present invention may be gelled and formed into a molded article for use as a pressure-sensitive adhesive. Such pressure-sensitive adhesives using the pressure-sensitive adhesive composition of the present invention can be suitably used as pressure-sensitive adhesives for composite materials formed by bonding various materials together. For example, the pressure-sensitive adhesive composition of the present invention may be polymerized and / or crosslinked in contact with a first material and a second material, thereby bonding the first material and the second material together to form a composite, thereby obtaining a composite material. Alternatively, the pressure-sensitive adhesive composition of the present invention may be gelled in advance to form a sheet-like or layer-like molded article, which may then be interposed between the first material and the second material to form a composite, thereby obtaining a composite material. When obtaining a composite material, a continuous 0.2 cm ２ The surfaces of the above areas may be bonded together. When bonding together to form a composite, it may be applied in a solid manner or in a dotted pattern.

[0133] Furthermore, the pressure-sensitive adhesive composition and molded article of the present invention can be easily peeled off after use, for example, by adding water to the composite material after use. From the viewpoint of facilitating such peeling and further improving the peeling speed, the pressure-sensitive adhesive composition and molded article of the present invention are capable of absorbing water in an amount by weight 5 times or more relative to the weight of the cationic group-containing polymer, so that the cationic group-containing polymer is preferably swellable in water or soluble in water. In the pressure-sensitive adhesive composition and molded article of the present invention, the amount of water absorbed relative to the weight of the cationic group-containing polymer is more preferably 10 times or more, even more preferably 15 times or more, and even more preferably 20 times or more. The upper limit is not particularly limited, but is typically 200 times or less.

[0134] In a preferred embodiment, when the materials constituting the composite material are separated by dissolving or swelling the composite material and dismantled in this manner, an anionic substance (e.g., fatty acid soap) is applied to the composite material after dismantling to precipitate or dehydrate the cationic group-containing polymer, thereby further reducing the load on wastewater treatment and incineration.

[0135] Taking advantage of their properties, the pressure-sensitive adhesive composition and molded article of the present invention can be suitably used as an adhesive for, for example, radio wave shields, curtains, humidity conditioners, moisture collectors, moisture release materials, heat shields, stickers, badges, cushioning materials, vibration-proofing materials, fire-resistant and flame-retardant materials, etc.

[0136] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The terms "parts" are based on mass unless otherwise specified. The test methods used in these examples and comparative examples are as follows.

[0137] <Weight-Average Molecular Weight (Mw) and Molecular Weight Distribution (Mw / Mn)> (1) Weight-Average Molecular Weight (Mw) and Molecular Weight Distribution (Mw / Mn) of Base Polymer The weight-average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the base polymer obtained in Example 1 were measured in polystyrene equivalent values ​​by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent. The measuring instrument used was an HLC-8320 (manufactured by Tosoh Corporation), and four TSKgel SuperMultipore HZH (manufactured by Tosoh Corporation) columns connected in series, and the detector was a differential refractometer RI-8320 (manufactured by Tosoh Corporation).

[0138] (2) Weight-Average Molecular Weight (Mw) of Imidazolium Structure-Containing Polyether Compound The weight-average molecular weight (Mw) of the imidazolium structure-containing polyether compounds obtained in Examples 1 and 2 was determined as follows. That is, first, the average molecular weight of all repeating units constituting the imidazolium structure-containing polyether compound was determined from the average molecular weight of the repeating units of the base polymer, the average molecular weights of the various monomer units constituting the polyether compound, and the contents of the various monomer units determined by the following (3). The value obtained by multiplying the number of repeating units of the base polymer by the average molecular weight of all repeating units constituting the imidazolium structure-containing polyether compound was then used as the number-average molecular weight (Mw) of the polyether compound.

[0139] (3) Structures of the base polymer and the imidazolium structure-containing polyether compound, and the content of the monomer units in the base polymer and the imidazolium structure-containing polyether compound The structures of the base polymer and the imidazolium structure-containing polyether compound, and the content of the monomer units in the base polymer and the imidazolium structure-containing polyether compound were measured using a nuclear magnetic resonance (NMR) spectrometer as follows. That is, first, 30 mg of a sample of the base polymer or the imidazolium structure-containing polyether compound was added to 1.0 mL of deuterated chloroform or deuterated dimethyl sulfoxide, and the mixture was shaken for 1 hour to dissolve it uniformly. Then, the obtained solution was subjected to NMR measurement, １H-NMR spectra were obtained, and the structure of the sample was assigned according to standard methods. The content of the repeating unit represented by general formula (2) in the imidazolium structure-containing polyether compound containing the repeating unit represented by general formula (2) was calculated by the following method. First, the number of moles of all oxirane monomer units, B1, was calculated from the integral of the protons derived from the oxirane monomer units in the main chain. Next, the number of moles of the repeating unit represented by general formula (2), B2, was calculated from the integral of the protons derived from the imidazolium structure in the repeating unit represented by general formula (2). The ratio (percentage) of B2 to B1 was then calculated as the content of the repeating unit represented by general formula (2) in the imidazolium structure-containing polyether compound.

[0140] <Radio wave shielding performance against radio waves in the gigahertz band> A test specimen was prepared by sandwiching the radio wave shield (radio wave absorbing material layer) obtained in each example and comparative example to a thickness of 3 mm between two acrylic plates measuring 17 cm in length, 17 cm in width, and 2 mm in thickness. If the radio wave shield was a liquid or solution, an additional acrylic plate with a thickness of 7 mm was attached to the outer periphery of the two acrylic plates to ensure that the liquid was retained.

[0141] Then, using the test specimen prepared above, the return loss (dB) and transmission loss (dB) of radio waves in the gigahertz band were measured in an environment of 23°C and 36% RH. Specifically, for the test specimen prepared above, radio waves were irradiated perpendicularly to the test specimen using the free space method, and the S (Scattering) parameters (S11) and (S21) of the reflected wave and transmitted wave were measured. The measurement frequency was in the range of 5.6 to 110 GHz. The larger the return loss and transmission loss, the better the absorption performance and shielding performance. The return loss can be calculated using the following formula. Furthermore, the return loss was converted to reflectance. Return loss (dB) = 20 log |S11|

[0142] The measurement conditions were as follows: (Apparatus configuration) Free Space Microwave Measurement System (HVSFS, MAC Systems Corporation) Network analyzer: Keysight Technologies (Agilent Technologies), N5227N 10 MHz to 67 GHz Wave Guide T / R Module: Keysight Technologies (Agilent Technologies), N5260-60004 67 GHz to 110 GHz Millimeter-wave controller: Keysight Technologies (Agilent Technologies), 8510XF Transmitting and receiving antenna (C band): HVS Technology FSS-01 with dielectric lens Transmitting and receiving antenna (X band): HVS Technology FSS-04 with dielectric lens Transmitting and receiving antenna (Ku-W band): HVS Technology FSS-07 with dielectric lens Coaxial cable: Keysight Technologies (Agilent Technologies), 11500-60002 1 mm Test Cable (measurement conditions) Focal length: 30.5 cm based on the antenna-sample distance Polarization plane: Linear polarization (Horizontal / Vertical) Measurement frequency: 5.6 to 110 GHz

[0143] <Radio wave shielding performance against radio waves in the terahertz band> An acrylic optical measurement cell was used instead of the acrylic plate in the same manner as above, and the transmittance of radio waves in the terahertz band (infrared region) was evaluated using an ultraviolet-visible-near-infrared spectrophotometer (V-670 manufactured by JASCO Corporation). The measurement range was 100 to 300 THz, and the measurement was performed with an optical path length of 10 mm.

[0144] <Visible Light Transmittance> All test specimens prepared in the test for radio wave shielding performance against radio waves in the gigahertz band were visually inspected to determine whether objects on the other side of the sample were visible. Furthermore, the test specimens of Example 4 and Comparative Example 1 were also subjected to measurement of light transmittance in the visible light region. Specifically, for Example 4, the above test specimen from which the acrylic layer (acrylic plate) had been peeled was used, and for Comparative Example 1, a test specimen with a thickness of 3 mm was used. The transmittance of light in the visible light region was evaluated using an ultraviolet-visible-near-infrared spectrophotometer (V-670 manufactured by JASCO Corporation). The measurement range was 400 to 800 nm.

[0145] <Ionic Conductivity> The ionic conductivity of the radio wave shielding bodies obtained in each of the Examples and Comparative Examples was measured by an AC impedance method using an impedance analyzer (product name "Impedance Analyzer", manufactured by Solartron Corporation), and evaluated according to the following criteria: A: Ionic conductivity was 1.0 × 10 －７ S / cm or more B: Ion conductivity is 1.0 x 10 －７ Less than S / cm

[0146] Example 1 (Living Anionic Polymerization of Epichlorohydrin) 3.22 g of tetra-n-butylammonium bromide and 30 ml of toluene were added to an argon-purged glass reactor equipped with a stirrer and cooled to 0°C. Next, a solution of 1.37 g of triethylaluminum in 10 ml of n-hexane was added, and the reaction was allowed to proceed for 15 minutes to obtain a catalyst composition. 10.0 g of epichlorohydrin was added to the obtained catalyst composition, and a polymerization reaction was carried out at 0°C. After the start of the polymerization reaction, the viscosity of the solution gradually increased. After the reaction time of 12 hours, a small amount of water was added to the polymerization reaction solution to terminate the reaction. The obtained polymerization reaction solution was washed with a 0.1 N aqueous hydrochloric acid solution to deash the catalyst residue, and then further washed with ion-exchanged water. The organic phase was then dried under reduced pressure at 50°C for 12 hours. The yield of the resulting colorless, transparent oily substance was 9.9 g. The weight average molecular weight (Mn) of the obtained substance measured by GPC was 11,300, and the molecular weight distribution (Mw / Mn) was 1.13.

[0147] (Quaternization of epichlorohydrin oligomer with 1-methylimidazole) 5.0 g of the epichlorohydrin oligomer obtained above, 12.1 g of 1-methylimidazole, and 10.0 g of acetonitrile were added to a glass reactor equipped with a stirrer and purged with argon, and heated to 80°C. After reacting at 80°C for 48 hours, the reaction was stopped by cooling to room temperature. The resulting reaction product was washed with an equal weight mixed solution of toluene / methanol / water, and the organic phase containing 1-methylimidazole and toluene was removed. The aqueous phase was dried under reduced pressure at 50°C for 12 hours, yielding 9.4 g of a pale red solid. Regarding this solid, １ H-NMR measurement and elemental analysis identified the compound as an imidazolium structure-containing polyether compound having a halide ion as a counter anion (a cation group-containing polyether composed of repeating units represented by formula (6) below), in which all of the chloro groups in the repeating units of the starting epichlorohydrin oligomer had been substituted with 1-methylimidazolium groups having a chloride ion as a counter anion, and the bromo group of the bromomethyl group at the polymerization initiation terminal had been substituted with a 1-methylimidazolium group having a bromide ion as a counter anion. The resulting imidazolium structure-containing polyether compound having a halide ion as a counter anion had a weight-average molecular weight (Mw) of 18,500 and a molecular weight distribution (Mw / Mn) of 1.13, as determined by GPC.

[0148] Water was added to the obtained imidazolium structure-containing polyether compound having a halide ion as a counter anion to adjust the solid content to 56% by weight, and a viscous liquid radio wave shielding material was obtained. The radio wave shielding performance against radio waves in the gigahertz band, radio wave shielding performance against radio waves in the terahertz band, visible light transmittance, and electrical conductivity were measured according to the above-mentioned methods. The results are shown in Tables 1 and 2.

[0149] Example 2 (Anion exchange of imidazolium structure-containing polyether compound having halide ions as counter anions with lithium bis(trifluoromethylsulfonyl)imide) 2.5 g of the imidazolium structure-containing polyether compound having halide ions as counter anions obtained in Example 1, 4.1 g of lithium bis(trifluoromethylsulfonyl)imide, and 20 mL of ion-exchanged water were added to a glass reactor equipped with a stirrer. After reacting for 30 minutes at room temperature, the mixture was dried under reduced pressure at 50°C for 12 hours. The resulting solid-liquid mixture was washed with water to remove inorganic salts, and the liquid phase was extracted with toluene. The resulting toluene solution was dried under reduced pressure at 50°C for 12 hours, yielding 5.7 g of a nearly colorless, transparent viscous liquid substance. Regarding the resulting viscous liquid substance: １ H-NMR spectroscopy and elemental analysis identified the resulting compound as a polyether compound having bis(trifluoromethylsulfonyl)imide anions as counter anions (a cationic group-containing polyether composed of repeating units represented by formula (7) below), in which all of the chloride and bromide ions in the starting polyether compound having imidazolium structures and halide ions as counter anions had been exchanged with bis(trifluoromethylsulfonyl)imide anions. The resulting polyether compound having bis(trifluoromethylsulfonyl)imide anions as counter anions had a weight-average molecular weight (Mw) of 45,000 and a molecular weight distribution (Mw / Mn) of 1.13, as determined by GPC.

[0150] The obtained imidazolium structure-containing polyether compound having bis(trifluoromethylsulfonyl)imide anion as a counter anion was used as it was to prepare a viscous liquid radio wave shielding material, and the radio wave shielding performance against radio waves in the gigahertz band, the radio wave shielding performance against radio waves in the terahertz band, the visible light transmittance, and the electrical conductivity were measured according to the above-mentioned methods. The results are shown in Tables 1 and 2.

[0151] Example 3 An aqueous solution of a dimethylamine-epichlorohydrin-ethylenediamine condensate (manufactured by Sigma-Aldrich Corporation, weight-average molecular weight (Mw) = 250,000) consisting of a repeating unit represented by the following formula (8) was prepared, and the solids concentration was adjusted to 80 wt % to obtain a viscous liquid radio wave shielding material. This was used to measure radio wave shielding performance against radio waves in the gigahertz band, radio wave shielding performance against radio waves in the terahertz band, visible light transmittance, and electrical conductivity according to the methods described above. The results are shown in Tables 1 and 2. FIG. 1 shows graphs of the return loss and transmission attenuation in the gigahertz band for Example 3, and FIG. 2 shows a graph of the absorptance in the gigahertz band. The absorptance graph in FIG. 2 shows a graph of the absorptance as a radio wave shielding material, taking into account the return loss and transmission attenuation.

[0152] Example 4 One part of methylenebismethacrylamide (Sigma-Aldrich) as a crosslinking agent and one part of 2-hydroxy-4'-(-2-hydroxyethoxy)-2-methylpropiophenone (Tokyo Chemical Industry Co., Ltd.) as a photopolymerization initiator were dissolved in 100 parts of a diallyldimethylammonium chloride solution (Sigma-Aldrich, 60 wt % aqueous solution). The solution was then irradiated with 365 nm UV light to cause polymerization and crosslinking, yielding a sheet-like radio wave shielding material (containing 40 wt % water) made of a crosslinked poly(diallyldimethylammonium chloride) consisting of repeating units represented by the following formula (9). The sheet was flexible and repeatedly stretchable. Using this sheet, radio wave shielding performance against gigahertz radio waves, radio wave shielding performance against terahertz radio waves, visible light transmittance, visible light transmittance, and electrical conductivity were measured according to the methods described above. The results are shown in Tables 1 and 2. FIG. 3 shows a graph of visible light transmittance (the results of Example 4 are shown by the solid line).

[0153] Example 5: 100 parts of a (3-acrylamidopropyl)trimethylammonium chloride solution (Sigma-Aldrich, 75 wt % aqueous solution) were dissolved with 1 part of methylenebisacrylamide (Sigma-Aldrich) as a crosslinking agent and 1 part of 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxymethylpropanone (Tokyo Chemical Industry Co., Ltd.) as a photopolymerization initiator. This solution was then irradiated with 365 nm UV light to cause polymerization and crosslinking, yielding a sheet-like radio wave shielding material (containing 25 wt % water) made of a crosslinked polymer (B) containing side chain ammonium groups and consisting of repeating units represented by the following formula (10). The sheet was flexible and repeatedly stretchable. The obtained sheet-like radio wave shielding material was then used to measure radio wave shielding performance against gigahertz and terahertz radio waves, visible light transmittance, and electrical conductivity according to the methods described above. The results are shown in Tables 1 and 2.

[0154] Comparative Example 1 Using a 10 mm sheet of polymethyl methacrylate (manufactured by Mitsubishi Chemical Corporation), radio wave shielding performance against radio waves in the gigahertz band, radio wave shielding performance against radio waves in the terahertz band, visible light transmittance, visible light transmittance, and electrical conductivity were measured according to the above-mentioned methods. The results are shown in Tables 1 and 2. A graph of visible light transmittance is also shown in Figure 3 (the results of Comparative Example 1 are shown by the dashed line). A 3 mm thick sheet was used to measure visible light transmittance.

[0155]

[0156]

[0157] As shown in Tables 1 and 2, it can be confirmed that radio wave shielding bodies containing cationic group-containing polymers having cationic groups in the polymer chains have high reflection attenuation or reflectance, transmission attenuation, or absorption rate for radio waves in the gigahertz band, low transmittance in the terahertz band, excellent radio wave shielding performance, and further high transmittance for visible light and excellent transparency (Examples 1 to 5). Furthermore, the radio wave shielding bodies according to Examples 1 to 5 have an ionic conductivity of 1.0 × 10 －７The ionic dissociation was sufficient, and the elasticity and flexibility were high, which made the film easy to process and less susceptible to breakage. Fig. 1 shows a graph of the return loss and transmission attenuation in the gigahertz band for Example 3, Fig. 2 shows a graph of the absorptance that combines the effects of return loss and transmission attenuation, and Fig. 3 shows a graph of the visible light transmittance for Example 4 and Comparative Example 1.

[0158] Example 6 One part of hexamethylene diisocyanate was mixed with 10 parts of an aqueous solution of a dimethylamine-epichlorohydrin-ethylenediamine condensate (manufactured by Sigma-Aldrich, weight average molecular weight (Mw) = 250,000) consisting of the repeating unit represented by formula (8) above, and the mixture was allowed to stand for 24 hours to allow the crosslinking reaction to proceed. As a result of the reaction, the mixture lost its fluidity, and a flexible crosslinked body that was capable of repeated stretching was obtained. The resulting crosslinked body was transparent and, like Example 3, functioned as a radio wave shielding body and also functioned as an ion conductor.

[0159] Example 7 One part of ethylene glycol diglycidyl ether was mixed with 10 parts of an aqueous solution of a dimethylamine-epichlorohydrin-ethylenediamine condensate (manufactured by Sigma-Aldrich Corporation, weight average molecular weight (Mw) = 250,000) consisting of the repeating unit represented by formula (8) above, and the mixture was allowed to stand for 24 hours to allow the crosslinking reaction to proceed. As a result of the reaction, the mixture lost its fluidity, and a flexible crosslinked body capable of repeated stretching was obtained. The resulting crosslinked body was transparent and, like Example 3, functioned as a radio wave shielding body and also functioned as an ion conductor.

[0160] Example 8 The radio wave shielding performance against radio waves in the gigahertz band was measured in the same manner as described above, except that the radio wave shielding bodies obtained in Examples 4 and 5 were not sandwiched between acrylic plates as exterior materials. The results are shown in Table 3.

[0161]

[0162] The results in Table 3 confirm that the use of an exterior material reduces reflected radio waves. Table 3 also shows the results when an acrylic plate was used as the exterior material.

[0163] Example 9 The radio wave shielding performance (return loss) against gigahertz-band radio waves was measured for the radio wave shielding body obtained in Example 5 in the same manner as described above, except that the angle of the incident radio waves was changed (tilted by 30° and 60° from a position directly facing the direction of the radio waves). The measurements were performed at 30 GHz and 90 GHz. The results are shown in Table 4.

[0164]

[0165] From the results in Table 4, it can be seen that the greater the angle of the incident radio wave, the greater the amount of transmission attenuation and the less the transmitted radio wave.

[0166] Example 10 A graphite-containing radio wave shielding material was produced by adding graphite to the same composition as in Example 5. Here, graphite is a material that exhibits radio wave absorption properties through a mechanism different from that of the cationic group-containing polymer used in the present invention. Specifically, it was produced by the following method. 5 parts of a (3-acrylamidopropyl)trimethylammonium chloride solution (Sigma-Aldrich, 75 wt % aqueous solution), 0.01 parts of tetramethylethylenediamine, and 0.050 parts of a 10 wt % aqueous ammonium persulfate solution were weighed and mixed thoroughly, and then 0.05 parts of graphite was added and mixed to achieve a good dispersion. This mixed solution was allowed to stand for 24 hours to allow thermal polymerization to proceed at room temperature, resulting in a black, sheet-like graphite-containing radio wave shielding material. The radio wave shielding performance (return loss) of the obtained graphite-containing radio wave shielding material against radio waves in the gigahertz band was measured using the same method as described above. The measurements were performed at 30 GHz and 90 GHz. The results are shown in Table 5 together with the measurement results for the radio wave shield of Example 5.

[0167]

[0168] The results in Table 5 confirm that the radio wave shielding properties can be further improved by using graphite in combination, which is a material that exhibits radio wave absorbing properties through a mechanism different from that of the cationic group-containing polymer.

[0169] Example 11 A combustion test was conducted on the radio wave shields obtained in Examples 1 to 5 and Comparative Example 1. For comparison, a combustion test was also conducted on an acrylic transparent double-sided adhesive sheet (manufactured by Daiso Co., Ltd.) and a polyurethane transparent double-sided adhesive sheet (manufactured by Daiso Co., Ltd.). The combustion test was conducted by measuring out 100 mg of the liquid sample and cutting out a 100 mg piece of the sheet sample, placing each on a stainless steel plate, and applying a lighter flame for 5 seconds to check the combustion behavior. The results are shown in Table 6.

[0170]

[0171] The results in Table 6 confirm that the radio wave shielding material containing the cationic group-containing polymer also has excellent flame resistance.

[0172] Example 12 In the same manner as in Example 5, a sheet-like radio wave shielding material (containing 25% by weight of water) was obtained, which was made of a crosslinked product of the side-chain ammonium group-containing polymer (B) consisting of the repeating unit represented by the above formula (10). The thickness of the sheet-like radio wave shielding material was 6 mm. The specific gravity of the obtained sheet-like radio wave shielding material was measured, and it was found to be 1.2 g / cm. ３ and conductive carbon (approximately 1.8 g / cm) known as a radio wave absorbing material. ３ ) and magnetic materials (approximately 4 g / cm ３ It was confirmed that the sheet-like radio wave shielding material obtained was lighter than conventional materials (see above). Furthermore, when the Duro-A hardness measurement was carried out in accordance with JIS K 7215-1986 using the obtained sheet-like radio wave shielding material, the result was HDA 6, indicating that the material was very flexible. Note that conductive carbon and magnetic materials known as radio wave absorbing materials are very hard materials and have poor flexibility.

[0173] Example 13 (Adhesive Sheet) A pressure-sensitive adhesive sheet comprising a crosslinked product of the side-chain ammonium group-containing polymer (B) comprising a repeating unit represented by the above formula (10) was obtained in the same manner as in Example 5, except that water was added to the solution obtained in the same manner as in Example 5. In this example, the polymer weight content was adjusted to 60 wt %, the water content was adjusted to 40 wt %, and the sheet thickness was set to 6 mm. When the Duro-A hardness of the obtained pressure-sensitive adhesive sheet was measured in accordance with JIS K 7215-1986, the result was HDA 0, indicating that the sheet was very flexible.

[0174] Example 14 (Adhesive Sheet) In the same manner as in Example 5, an adhesive sheet was obtained comprising a crosslinked product of a side-chain ammonium group-containing polymer (B) comprising a repeating unit represented by the above formula (10). In this example, the polymer weight content was adjusted to 75 wt %, the water content was adjusted to 25 wt %, and the thickness was adjusted to 1 mm. The obtained adhesive sheet was placed on a glass plate, and the blade of a cutter knife was pressed firmly against it from above and held for 5 seconds. As a result, although marks were left on the surface due to the cutter hitting the sheet, no cutting occurred and the sheet had sufficient strength. Separately, by performing the same procedure except for adding water, an adhesive sheet comprising a crosslinked product of a side-chain ammonium group-containing polymer (B) having a polymer weight content of 50 wt %, a water content of 50 wt %, and a thickness of 1 mm was obtained. Similarly, this adhesive sheet was placed on a glass plate, and the blade of a cutter knife was pressed firmly against it from above and held for 5 seconds. The sheet was cut into two pieces at the area where the cutter pressed, indicating insufficient strength.

[0175] Example 15 (Adhesive Sheet) A 1 mm-thick adhesive sheet was obtained from a crosslinked polymer (B) containing a side-chain ammonium group and a repeating unit represented by the formula (10) in the same manner as in Example 5. In this example, two glass plates measuring 10 cm × 10 cm × 1 mm were used as exterior materials, and the 1 mm-thick adhesive sheet prepared above was sandwiched between the glass plates to form a crosslinking reaction. Two such test specimens were prepared, with the ends of the test specimens left open and no special sealing was performed. When one of the test specimens was used to evaluate adhesive strength, the two glass plates were well bonded, and even when force was applied to separate the two glass plates, they did not separate. When greater force was applied, the glass plate broke. The other test specimen was submerged in a water tank for 24 hours; the adhesive sheet absorbed water and swelled, causing the two glass plates to naturally separate. From these results, it can be said that the composite material as an adherend can be easily dismantled without applying any special force, and the pressure-sensitive adhesive of the present invention can provide a composite material with excellent recyclability. The swollen pressure-sensitive adhesive sheet had a thickness three times or more of its original thickness.

[0176] Example 16 (Adhesive Sheet) In the same manner as in Example 4, a 1 mm thick adhesive sheet was obtained, which consisted of a crosslinked product of poly(diallyldimethylammonium chloride) comprising the repeating unit represented by the above formula (9). In this example, as in Example 16, two glass plates measuring 10 cm x 10 cm x 1 mm were used as exterior materials, and the 1 mm thick adhesive sheet obtained above was sandwiched between these glass plates, thereby carrying out a crosslinking reaction to form the sheet. In this example, two such test specimens were also prepared and evaluated in the same manner as in Example 15. The evaluation results for adhesive strength and the results when submerged in a water tank were similar to those of Example 15.

[0177] Comparative Example 2: Two test specimens were prepared by sandwiching a 10 cm x 10 cm x 1 mm acrylic adhesive sheet between two glass plates in the same manner as in Example 15. The adhesive strength was evaluated in the same manner as in Example 15. The two glass plates were well bonded, and even when force was applied to try to separate them, they did not come off. When a stronger force was applied, the glass plates broke. On the other hand, when the test specimens were submerged in a water tank and left for 24 hours in the same manner as in Example 15, no particular change was observed, and the glass plates could not be peeled off.

[0178] Comparative Example 3: Starch glue was used as the water-soluble adhesive, and a test specimen sandwiched between two glass plates was prepared in the same manner as in Example 15. However, even after 24 hours, the starch glue was barely dry, and it was not possible to bond the two glass plates. Therefore, a thin layer of starch glue was spread on one glass plate and dried in that state to form a starch glue layer 1 mm thick. Another glass plate was then placed on top of the glass plate in an attempt to bond them, but the dried starch glue had neither tackiness nor adhesiveness, and it was not possible to prepare a composite material.

[0179] Example 17 (Adhesive Layer) Cellophane paper was prepared as a substrate, and the solution prepared in Example 15 was applied thereto to form a 50 μm-thick adhesive layer. This was then cut into a 2 cm x 4 cm piece to produce cellophane tape. The resulting cellophane tape was used to attach A4-sized copy paper to a wall. The tape did not peel off even after one year, maintaining good adhesive strength. The moisture content of the tape after one year was 15% or more. The cellophane paper with the adhesive layer formed thereon was cut into a 2 cm x 15 cm piece and used as tape to secure gauze to a person's arm. The tape adhered well to both the gauze and the human body, functioning well as a tape. Furthermore, when the tape was removed, it naturally peeled off when water was applied, causing no pain to the skin. On the other hand, when a commercially available tape was used in the same manner, the tape pulled the skin and hair during removal, resulting in pain.

[0180] Example 18 (Adhesive Layer) Two glass slides (7.5 cm × 2.5 cm × 110 μm) were prepared. A few drops of the solution prepared in Example 5 were dropped onto one of the glass slides at a position 1.5 cm from the edge. Then, a polyethylene film (4 cm square, 25 μm thick) was placed on top of the glass slide. A few drops of the solution prepared in Example 5 were dropped onto the other glass slide. Finally, another glass slide was placed on top of the other glass slide, shifted in the length direction, and pressed firmly to prevent the solution from leaking out from the edge. In this example, the two glass slides and the polyethylene film were overlapped so that the overlapping length was 3 cm (overlapping area: 3 cm × 2.5 cm). Next, the dropped solution was irradiated with 365 nm UV light to polymerize and crosslink between the layers, thereby forming an adhesive layer (containing 25 wt % water) made of a crosslinked product of the side-chain ammonium group-containing polymer (B) consisting of the repeating unit represented by the above formula (10). In this example, three such test specimens were prepared. One test specimen was used to evaluate adhesive strength. It was found to be well bonded, and attempts to separate the two glass slides with force failed; however, the glass slide broke when strong force was applied. Another test specimen was placed in a household microwave oven (600 W, 2.45 GHz) and heated for 15 seconds. The test specimen separated from the polyethylene. This is believed to be due to the adhesive layer absorbing microwaves, generating heat, which generated high-temperature steam, pushing the interface apart and causing separation. This test specimen showed almost no temperature increase outside the bonded area, and could be held with bare hands. Furthermore, the adhesive cured material remaining on the glass slide still adhered well, but when water was applied, it quickly swelled and could be wiped off with gentle force, demonstrating excellent dismantling properties. Another test specimen was heated at the bonded area with a household hair dryer (1200 W). No change was observed after 15 seconds, but after 45 seconds of heating, the glass slide could be peeled off without breaking when force was applied. When heated with this dryer, areas other than the joint also became hot.

[0181] Example 19 (Adhesive Layer) Three test specimens were obtained in the same manner as in Example 18, except that the solution prepared in Example 4 was used, and evaluation was performed in the same manner. As a result, the same results as in Example 18 were obtained.

Claims

1. A radio wave shielding material containing a cation group-containing polymer having a cation group in the polymer chain.

2. The radio wave shielding body according to claim 1, comprising the aforementioned cationic group-containing polymer in a proportion of 1 to 100% by weight.

3. A radio wave shielding body according to claim 1 or 2, which shields radio waves with a frequency of 1 GHz or more and 300 THz or less.

4. The radio wave shielding body according to claim 1 or 2, further comprising an outer casing.

5. A sheet comprising the radio wave shielding body according to claim 1 or 2.

6. A partition member including the radio wave shielding body according to claim 1 or 2.

7. The partition member according to claim 6, which is a component used in screens, humidity control materials, heat shielding materials, curtains, windows, wall materials, eyeglasses, housings for electrical circuit products, or inside electrical circuit products.

8. A sealing material comprising the radio wave shielding body according to claim 1 or 2.

9. A sticky composition containing a cation group-containing polymer having a cation group in its polymer chain, and water, An adhesive composition wherein the content of the cationic group-containing polymer in the adhesive composition is 55% by weight or more and 95% by weight or less, and the content of water is 5% by weight or more and 45% by weight or less.

10. The adhesive composition according to claim 9, which is capable of absorbing water at a weight of five times or more relative to the weight of the cation group-containing polymer, thereby enabling the cation group-containing polymer to swell in water or to be soluble in water.

11. The adhesive composition according to claim 9 or 10, which is curable by polymerization and / or crosslinking.

12. A molded article obtained by gelling the adhesive composition according to claim 9 or 10.

13. The molded article according to claim 12, which is capable of absorbing water at a weight of five times or more relative to the weight of the cationic group-containing polymer, thereby enabling the cationic group-containing polymer to swell in water or to be soluble in water.

14. An adhesive comprising the adhesive composition according to claim 9 or 10.

15. A composite material bonded together via an adhesive as described in claim 14.

16. A method for compounding a first material and a second material by polymerizing and / or crosslinking the adhesive composition described in claim 11 while it is in contact with the first material and the second material.